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Sample records for accord lipid study

  1. The PCOS Patients differ in Lipid Profile According to their Phenotypes.

    Science.gov (United States)

    Spałkowska, Magdalena; Mrozińska, Sandra; Gałuszka-Bednarczyk, Anna; Gosztyła, Katarzyna; Przywara, Agnieszka; Guzik, Justyna; Janeczko, Marek; Milewicz, Tomasz; Wojas-Pelc, Anna

    2018-01-31

    Polycystic ovary syndrome (PCOS) affects 4-18% of women of reproductive age. The number of reports exploring the lipid profiles among PCOS patients and number of studied patients are limited. The aim of our study was to assess the lipid profile separately in lean and non-lean women with polycystic ovary syndrome divided according to hyperandrogenemia, defined as free androgen index (FAI)≥5. The second aim was to compare the lipid profiles among lean and non-lean PCOS patients with respect to hyperandrogenemia and regularity of menstruation cycles. We evaluated 232 patients from Department of Endocrinological Gynecology, Jagiellonian University Medical College in Krakow diagnosed with PCOS. The population consisted of 166 lean and 66 non-lean women. We observed higher levels of total cholesterol, high-density lipoprotein cholesterol (HDL-C) in lean patients with FAIlean patients with FAI≥5. There were no differences in lipid profile between non-lean patients with FAI≥5 and non-lean patients with FAIlean patients higher total cholesterol levels were observed in those with irregular menstruation cycles and FAIlean PCOS patients. The results of our study showed differences in lipid profile between lean PCOS patients according to their phenotype based on androgens' level. This effect was abandoned by fat tissue mass in non-lean ones. Further studies should be conducted to explore these associations. © Georg Thieme Verlag KG Stuttgart · New York.

  2. Dyslipidemias and Cardiovascular Prevention: Tailoring Treatment According to Lipid Phenotype.

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    Sanin, Veronika; Pfetsch, Vanessa; Koenig, Wolfgang

    2017-07-01

    This study aimed to present the current information on the genetic background of dyslipidemias and provide insights into the complex pathophysiological role of several plasma lipids/lipoproteins in the pathogenesis of atherosclerotic cardiovascular disease. Furthermore, we aim to summarize established therapies and describe the scientific rationale for the development of novel therapeutic strategies. Evidence from genetic studies suggests that besides lowering low-density lipoprotein cholesterol, pharmacological reduction of triglyceride-rich lipoproteins, or lipoprotein(a) will reduce risk for coronary heart disease. Dyslipidemia, in particular hypercholesterolemia, is a common clinical condition and represents an important determinant of atherosclerotic vascular disease. Treatment decisions are currently guided by the causative lipid phenotype and the presence of other risk factors suggesting a very high cardiovascular risk. Therefore, the identification of lipid disorders and the optimal combination of therapeutic strategies provide an outstanding opportunity for reducing the onset and burden of cardiovascular disease.

  3. Common and rare genetic markers of lipid variation in subjects with type 2 diabetes from the ACCORD clinical trial

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    Skylar W. Marvel

    2017-05-01

    Full Text Available Background Individuals with type 2 diabetes are at an increased risk of cardiovascular disease. Alterations in circulating lipid levels, total cholesterol (TC, low-density lipoprotein (LDL, high-density lipoprotein (HDL, and triglycerides (TG are heritable risk factors for cardiovascular disease. Here we conduct a genome-wide association study (GWAS of common and rare variants to investigate associations with baseline lipid levels in 7,844 individuals with type 2 diabetes from the ACCORD clinical trial. Methods DNA extracted from stored blood samples from ACCORD participants were genotyped using the Affymetrix Axiom Biobank 1 Genotyping Array. After quality control and genotype imputation, association of common genetic variants (CV, defined as minor allele frequency (MAF ≥ 3%, with baseline levels of TC, LDL, HDL, and TG was tested using a linear model. Rare variant (RV associations (MAF < 3% were conducted using a suite of methods that collapse multiple RV within individual genes. Results Many statistically significant CV (p < 1 × 10−8 replicate findings in large meta-analyses in non-diabetic subjects. RV analyses also confirmed findings in other studies, whereas significant RV associations with CNOT2, HPN-AS1, and SIRPD appear to be novel (q < 0.1. Discussion Here we present findings for the largest GWAS of lipid levels in people with type 2 diabetes to date. We identified 17 statistically significant (p < 1 × 10−8 associations of CV with lipid levels in 11 genes or chromosomal regions, all of which were previously identified in meta-analyses of mostly non-diabetic cohorts. We also identified 13 associations in 11 genes based on RV, several of which represent novel findings.

  4. Does feed restriction and re-alimentation differently affect lipid content and metabolism according to muscle type in pigs (Sus scrofa)?

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    Gondret, Florence; Lebret, Bénédicte

    2007-06-01

    This study aimed to investigate whether feed restriction and re-alimentation differently affect lipid content and activities of lipogenic or catabolic enzymes according to muscle types in pigs. At around 28 kg body mass (BW), sixty pigs (n=30 per group) were allocated to either ad libitum (AL) or restricted/re-feeding (RA) regimens. After feed restriction (80 kg BW), lipid content was reduced (P<0.01) in the oxidative rhomboideus (RH) as in the glycolytic biceps femoris (BF) muscles of RA pigs compared with AL pigs. Lower activities (P<0.05) of the lipogenic enzymes fatty acid synthase (FAS) and malic enzyme (ME) were observed in the RH but not in the BF of RA vs. AL pigs. After re-feeding (110 kg BW), lipid content was restored in the RH, but was still 12% lower (P<0.05) in the BF of RA compared with AL pigs. In the RH, the trend for an enhanced FAS activity and for a smaller weight-related decrease of ME activity in RA pigs than AL pigs during re-feeding, may have contributed to the muscle fat recovery observed in the RA pigs. In the BF, higher oxidative enzyme activities (P<0.10) in RA pigs compared to AL pigs might explain the incomplete lipid recovery observed after re-feeding in the former animals. In conclusion, metabolic activities in response to restriction and re-feeding differed according to muscle metabolic type.

  5. A novel method to produce solid lipid nanoparticles using n-butanol as an additional co-surfactant according to the o/w microemulsion quenching technique.

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    Mojahedian, Mohammad M; Daneshamouz, Saeid; Samani, Soliman Mohammadi; Zargaran, Arman

    2013-09-01

    Solid Lipid Nanoparticles (SLN) and Nanostructured Lipid Carriers (NLC) are novel medicinal carriers for controlled drug release and drug targeting in different roots of administration such as parenteral, oral, ophthalmic and topical. These carriers have some benefits such as increased drug stability, high drug payload, the incorporation of lipophilic and hydrophilic drugs, and no biotoxicity. Therefore, due to the cost-efficient, proportionally increasable, and reproducible preparation of SLN/NLC and the avoidance of organic solvents used, the warm microemulsion quenching method was selected from among several preparation methods for development in this research. To prepare the warm O/W microemulsion, lipids (distearin, stearic acid, beeswax, triolein alone or in combination with others) were melted at a temperature of 65°C. After that, different ratios of Tween60 (10-22.5%) and glyceryl monostearate (surfactant and co-surfactant) and water were added, and the combination was stirred. Then, 1-butanol (co-surfactant) was added dropwise until a clear microemulsion was formed and titration continued to achieve cloudiness (to obtain the microemulsion zone). The warm o/w microemulsions were added dropwise into 4°C water (1:5 volume ratio) while being stirred at 400 or 600 rpm. Lipid nanosuspensions were created upon the addition of the warm o/w microemulsion to the cold water. The SLN were obtained over a range of concentrations of co-surfactants and lipids and observed for microemulsion stability (clearness). For selected preparations, characterization involved also determination of mean particle size, polydispersity and shape. According to the aim of this study, the optimum formulations requiring the minimum amounts of 1-butanol (1.2%) and lower temperatures for creation were selected. Mono-disperse lipid nanoparticles were prepared in the size range 77 ± 1 nm to 124 ± 21 nm according to a laser diffraction particle size analyzer and transmission electron

  6. Classification of metabolic syndrome according to lipid alterations: analysis from the Mexican National Health and Nutrition Survey 2006.

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    Pedroza-Tobias, Andrea; Trejo-Valdivia, Belem; Sanchez-Romero, Luz M; Barquera, Simon

    2014-10-09

    There are 16 possible Metabolic Syndrome (MS) combinations out of 5 conditions (glucose intolerance, low levels of high-density lipoprotein Cholesterol (HDL-C), high triglycerides, high blood pressure and abdominal obesity), when selecting those with at least three. Studies suggest that some combinations have different cardiovascular risk. However evaluation of all 16 combinations is complex and difficult to interpret. The purpose of this study is to describe and explore a classification of MS groups according to their lipid alterations. This is a cross-sectional study with data from the Mexican National Health and Nutrition Survey 2006. Subjects (n = 5,306) were evaluated for the presence of MS; four mutually-exclusive MS groups were considered: mixed dyslipidemia (altered triglycerides and HDL-C), hypoalphalipoproteinemia: (normal triglycerides but low HDL-C), hypertriglyceridemia (elevated triglycerides and normal HDL-C) and without dyslipidemia (normal triglycerides and HDL-C). A multinomial logistic regression model was fitted in order to identify characteristics that were associated with the groups. The most frequent MS group was hypoalphalipoproteinemia in females (51.3%) and mixed dyslipidemia in males (43.5%). The most prevalent combination of MS for both genders was low HDL-C + hypertension + abdominal obesity (20.4% females, 19.4% males). The hypoalphalipoproteinemia group was characteristic of women and less developed areas of the country. The group without dyslipidemia was more frequent in the highest socioeconomic level and less prevalent in the south of the country. The mixed dyslipidemia group was characteristic of men, and the Mexico City region. A simple system to classify MS based on lipid alterations was useful to evaluate prevalences by diverse biologic and sociodemographic characteristics. This system may allow prevention and early detection strategies with emphasis on population-specific components and may serve as a guide for

  7. Rhodopsin-lipid interactions studied by NMR.

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    Soubias, Olivier; Gawrisch, Klaus

    2013-01-01

    The biophysical properties of the lipid matrix are known to influence function of integral membrane proteins. We report on a sample preparation method for reconstitution of membrane proteins which uses porous anodic aluminum oxide (AAO) filters with 200-nm-wide pores of high density. The substrate permits formation of tubular, single membranes that line the inner surface of pores. One square centimeter of filter with a thickness of 60μm yields on the order of 500cm(2) of solid-supported single bilayer surface, sufficient for NMR studies. The tubular bilayers are free of detergent, fully hydrated, and accessible for ligands from one side of the membrane. The use of AAO filters greatly improves reproducibility of the reconstitution process such that the influence of protein on lipid order parameters can be studied with high resolution. As an example, results for the G protein-coupled receptor of class A, bovine rhodopsin, are shown. By (2)H NMR order parameter measurements, it is detected that rhodopsin insertion elastically deforms membranes near the protein. Furthermore, by (1)H saturation-transfer NMR under conditions of magic angle spinning, we demonstrate detection of preferences in interactions of rhodopsin with particular lipid species. It is assumed that function of integral membrane proteins depends on both protein-induced elastic deformations of the lipid matrix and preferences for interaction of the protein with particular lipid species in the first layer of lipids surrounding the protein. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. A STUDY OF LIPID PROFILE IN PREDIABETES

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    Manoj

    2016-06-01

    Full Text Available BACKGROUND Lipid abnormalities are common in diabetes mellitus and play an important role in acceleration of atherosclerosis leading to increased cardiovascular diseases. Due to increasing burden of diabetes, it is becoming important to identify dyslipidaemia in high-risk state for diabetes especially prediabetes so that early intervention can reduce cardiovascular risk. AIM To study lipid profile in prediabetes individuals. METHODS This study was a cross-sectional case control study which included 107 prediabetes and 101 healthy controls. Lipid profile of prediabetes and controls were measured and statistically analysed. RESULT Total cholesterol, LDL, triglycerides, VLDL, TG/HDL ratio, and LDL/HDL ratio were significantly high whereas HDL was significantly low in prediabetes subjects as compared to controls. CONCLUSION This study showed significant lipid abnormalities in prediabetes subjects. Because of these they are at high risk of developing atherosclerotic cardiovascular diseases. Therefore, proper screening and appropriate therapy of these conditions becomes important.

  9. Study on the influence of lipid peak to the results of MR spectroscopy in the central gland of prostate

    International Nuclear Information System (INIS)

    Dong Yanjun; Wang Xiaoying; Li Feiyu; Jiang Xuexiang

    2007-01-01

    Objective: To study the influence of lipid peak to MRS in central gland of prostate gland. Methods: Seventeen patients performed transurethral resection of prostate (TURP) for benign prostate hyperplasia (BPH) were enrolled in this study. Three groups were divided according to the pathological findings: glandular-BPH (GBPH) (7 cases), stromal-BPH (SBPH) (6 cases), and incidentally detected prostate carcinoma (IDPC) (4 cases). The voxel with lipid peak in the field of volume was counted. Compared with pathology, the following studies were performed: (1) The location of the voxels that more frequently presented lipid peak in the central gland. (2) Whether the appearance of the lipid peak would obscure the identification of the peaks of the endogenous metabolites. Results: The ratio of voxels with lipid peak in central gland was about 22.8% (834/3567). There were 1477 (397 voxels with lipid peak), 1434(396 voxels with lipid peak), and 656(41 voxels with lipid peak) voxels in CBPH, SBPH, and IDPC groups, respectively. The percentage in GBPH, SBPH, and IDPC groups was 23.6%, 27.2%, and 6.4%, respectively. The percentage of voxels with lipid peak at the edge of the central gland (79.6%, 68.6% and 72.4%, respectively) was higher than that in other regions. The lipid peak in most of the voxels didn't influence the identification of the citrate and choline peak (82.8%, 98.0%, and 96.4%, respectively). Conclusion: The lipid peak in the central gland may result from the lipid tissues near the gland, and most lipid peak had no influence on the identification of endogenous metabolites. (authors)

  10. [The mass-spectrometry studies of the interaction of polyhexamethyleneguanidine with lipids].

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    Lysytsia, A V; Rebriiev, A V

    2014-01-01

    In this work the integral components of the cytoplasmic membrane, lecithin and cholesterol were used for mass spectrometry analysis carried out on polyhexamethyleneguanidine (PHMG) mixtures with lipids. The study was performed by mass-spectrometry methods of the MALDI-TOF MS. Our results showed that despite the common use of PHGM polymer derivatives as disinfectants the persistent intermolecular complexes of PHMG oligomers with lipids were not formed. The binding of polycation PHMG with the membrane has been explained by the model proposed. According to this model PHGM can adhere to negatively charged plasma membrane of bacterial cell due to electrostatic interaction and the formation of loop-like structures. Similar stereochemistry mechanism makes the adsorption of the investigated polycation to membrane robust. The mechanism described together with additional destructive factors provides a reasonable explanation for the PHMG induced damage of bacterial cell plasma membrane and the biocide action of disinfectants prepared on the basis of the PHMG salts.

  11. A comparative study of lipids in Sphagnum species

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Baas, M.; Pancost, R.D.; Geel, B. van

    2000-01-01

    The free lipid compositions of twelve species of Sphagnum were determined by capillary gas chromatography/mass spectrometry as part of a study to identify characteristic lipids for Sphagnum in peat bogs. Complex mixtures of lipids, comprised of C28 C29 sterols, C30 triterpenoids, C16 C30 fatty

  12. Production and characterization of nanostructured lipid carriers and solid lipid nanoparticles containing lycopene for food fortification.

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    Akhoond Zardini, Ali; Mohebbi, Mohebbat; Farhoosh, Reza; Bolurian, Shadi

    2018-01-01

    In this study, lycopene, was loaded on nanostructured lipid carrier and solid lipid nanoparticles using combination of high shear homogenization and ultrasonication method. Effect of applied lipids types, nanocarrier's type and lycopene loading on physicochemical properties of developed nanocarriers were studied. Particle sizes of developed nanocarriers were between 74.93 and 183.40 nm. Encapsulation efficiency of nanostructured lipid carrier was significantly higher than solid lipid nanoparticles. Morphological study of developed nanocarriers using scanning electron microscopy showed spherical nanoparticles with smooth surface. Lycopene was entrapped in nanocarriers without any chemical interaction with coating material according to Fourier transform infrared spectroscopy spectrum and differential scanning calorimetry thermogram. Glycerol monostearate containing nanoparticles showed phase separation after 30 days in 6 and 25 °C, whereas this event was not observed in nanosuspensions that produced by glycerol distearate. Lycopene release in gastrointestinal condition was studied by the dialysis bag method. To evaluate nanocarrier's potential for food fortification, developed lycopene-loaded nanocarriers were added to orange drink. Results of sensory analysis indicated that nanoencapsulation could obviate the poor solubility and tomato after taste of lycopene. Fortified sample with lycopene nanocarriers didn't show significant difference with blank orange drink sample except in orange odor.

  13. Zebrafish yolk lipid processing: a tractable tool for the study of vertebrate lipid transport and metabolism

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    Rosa L. Miyares

    2014-07-01

    Full Text Available Dyslipidemias are a major cause of morbidity and mortality in the world, particularly in developed nations. Investigating lipid and lipoprotein metabolism in experimentally tractable animal models is a crucial step towards understanding and treating human dyslipidemias. The zebrafish, a well-established embryological model, is emerging as a notable system for studies of lipid metabolism. Here, we describe the value of the lecithotrophic, or yolk-metabolizing, stages of the zebrafish as a model for studying lipid metabolism and lipoprotein transport. We demonstrate methods to assay yolk lipid metabolism in embryonic and larval zebrafish. Injection of labeled fatty acids into the zebrafish yolk promotes efficient uptake into the circulation and rapid metabolism. Using a genetic model for abetalipoproteinemia, we show that the uptake of labeled fatty acids into the circulation is dependent on lipoprotein production. Furthermore, we examine the metabolic fate of exogenously delivered fatty acids by assaying their incorporation into complex lipids. Moreover, we demonstrate that this technique is amenable to genetic and pharmacologic studies.

  14. Heterogeneous behavior of lipids according to HbA1c levels undermines the plausibility of metabolic syndrome in type 1 diabetes: data from a nationwide multicenter survey

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    Giuffrida Fernando MA

    2012-12-01

    Full Text Available Abstract Background Cardiovascular risk factors (CVRF may cluster in type 1 diabetes, analogously to the metabolic syndrome described in type 2 diabetes. The threshold of HbA1c above which lipid variables start changing behavior is unclear. This study aims to 1 assess the behavior of dyslipidemia according to HbA1c values; 2 detect a threshold of HbA1c beyond which lipids start to change and 3 compare the clustering of lipids and other non-lipid CVRF among strata of HbA1c individuals with type 1 diabetes. Methods Effects of HbA1c quintiles (1st: ≤7.4%; 2nd: 7.5-8.5%; 3rd: 8.6-9.6%; 4th: 9.7-11.3%; and 5th: >11.5% and covariates (gender, BMI, blood pressure, insulin daily dose, lipids, statin use, diabetes duration on dyslipidemia were studied in 1275 individuals from the Brazilian multi-centre type 1 diabetes study and 171 normal controls. Results Body size and blood pressure were not correlated to lipids and glycemic control. OR (99% CI for high-LDL were 2.07 (1.21-3.54 and 2.51 (1.46-4.31, in the 4th and 5th HbA1c quintiles, respectively. Hypertriglyceridemia increased in the 5th quintile of HbA1c, OR 2.76 (1.20-6.37. OR of low-HDL-cholesterol were 0.48 (0.24-0.98 and 0.41 (0.19-0.85 in the 3rd and 4th HbA1c quintiles, respectively. HDL-cholesterol correlated positively (0.437 with HbA1c in the 3rd quintile. HDL-cholesterol and insulin dose correlated inversely in all levels of glycemic control. Conclusions Correlation of serum lipids with HbA1c is heterogeneous across the spectrum of glycemic control in type 1 diabetes individuals. LDL-cholesterol and triglycerides worsened alongside HbA1c with distinct thresholds. Association of lower HDL-cholesterol with higher daily insulin dose is consistent and it points out to a role of exogenous hyperinsulinemia in the pathophysiology of the CVRF clustering. These data suggest diverse pathophysiological processes depending on HbA1c, refuting a unified explanation for cardiovascular risk in type 1

  15. Study of association between beverage consumption pattern and lipid profile in shift workers.

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    Mashhadi, Nafiseh Shokri; Saadat, Saeed; Afsharmanesh, Mohammad Reza; Shirali, Saeed

    The circadian system influences on health and metabolic function that can cause raising some risk factor of metabolic syndrome. Few studies have examined data that incorporate the full complexity of daily beverage intake pattern on lipid profiles. The purpose of this study was to investigate relation between daily water and beverage intake of adults working in day or shift work and lipid profile. Total beverages intake was estimated in shift and administrative staff of Ahvaz International Airport, Iran. Forty five male, aged 25-55 years, attending this institute were invited to participate in this study. They completed a three-day food records and all participants were measured plasma lipid profiles. Forty one of participants completed all aspects of the study. Two clusters were emerged, labeled descriptively as Conventional including "high Sugar-sweetened drinkers" and "low sugar drinkers". The highest intake of water was in cluster 1 (1170.9ml/day) even this amount is much less than the daily recommended amounts. There were significant differences in triglyceride levels among day and night shift workers. According to the results, there is inadequacy of water and high sugar beverage intake among the shift workers which it is a potential risk of some related chronic diseases such as metabolic syndrome with high triglyceride level in the future. Copyright © 2016 Diabetes India. Published by Elsevier Ltd. All rights reserved.

  16. Study of inhibition on lipid oxidation of irradiated pork

    International Nuclear Information System (INIS)

    Ha Yiming

    2006-03-01

    It was studied that the effect factors of irradiation dose, preservation temperature, oxygen content and antioxidant on lipid oxidation of irradiated pork. A mechanism was explained on lipid oxidation of irradiated pork. The results showed that irradiation might aggravate lipid oxidation of pork and that decreased preservation temperature and oxygen content of the packaging, added antioxidant also could effectively inhibit lipid oxidation of irradiated pork. (authors)

  17. Тhe mass-spectrometry studies of the interaction of polyhexamethyleneguanidine with lipids

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    A. V. Lysytsya

    2014-02-01

    Full Text Available In this work the integral components of the cytoplasmic membrane, lecithin and cholesterol were used for mass spectrometry analysis carried out on polyhexamethyleneguanidine (PHMG mixtures with lipids. The study was performed by mass-spectrometry methods of the MALDI-TOF MS. Our results showed that despite the common use of PHGM polymer derivatives as disinfectants the persistent intermolecular complexes of PHMG oligomers with lipids were not formed. The binding of polycation PHMG with the membrane has been explained by the model proposed. According to this model PHGM can adhere to negatively charged plasma membrane of bacterial cell due to electrostatic interaction and the formation of loop-like structures. Similar stereochemistry mechanism makes the adsorption of the investigated polycation to membrane robust. The mechanism described together with additional destructive factors provides a reasonable explanation for the PHMG induced damage of bacterial cell plasma membrane and the biocide action of disinfectants prepared on the basis of the PНMG salts.

  18. Effect of pistachio diet on lipid parameters, endothelial function, inflammation, and oxidative status: a prospective study.

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    Sari, Ibrahim; Baltaci, Yasemin; Bagci, Cahit; Davutoglu, Vedat; Erel, Ozcan; Celik, Hakim; Ozer, Orhan; Aksoy, Nur; Aksoy, Mehmet

    2010-04-01

    Recent studies have suggested that nuts have favorable effects beyond lipid lowering. We aimed to investigate effect of the Antep pistachio (Pistacia vera L.) on blood glucose, lipid parameters, endothelial function, inflammation, and oxidation in healthy young men living in a controlled environment. A Mediterranean diet was administered to normolipidemic 32 healthy young men (mean age 22 y, range 21-24) for 4 wk. After 4 wk, participants continued to receive the Mediterranean diet but pistachio was added for 4 wk by replacing the monounsaturated fat content constituting approximately 20% of daily caloric intake. Fasting blood samples and brachial endothelial function measurements were performed at baseline and after each diet. Compared with the Mediterranean diet, the pistachio diet decreased glucose (Ppistachio diet significantly improved endothelium-dependent vasodilation (P=0.002, 30% relative increase), decreased serum interleukin-6, total oxidant status, lipid hydroperoxide, and malondialdehyde and increased superoxide dismutase (Ppistachio diet improved blood glucose level, endothelial function, and some indices of inflammation and oxidative status in healthy young men. These findings are in accordance with the idea that nuts, in particular pistachio nuts, have favorable effects beyond lipid lowering that deserve to be evaluated with prospective follow-up studies. Copyright 2010. Published by Elsevier Inc.

  19. A comparative study: the impact of different lipid extraction methods on current microalgal lipid research

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    2014-01-01

    Microalgae cells have the potential to rapidly accumulate lipids, such as triacylglycerides that contain fatty acids important for high value fatty acids (e.g., EPA and DHA) and/or biodiesel production. However, lipid extraction methods for microalgae cells are not well established, and there is currently no standard extraction method for the determination of the fatty acid content of microalgae. This has caused a few problems in microlagal biofuel research due to the bias derived from different extraction methods. Therefore, this study used several extraction methods for fatty acid analysis on marine microalga Tetraselmis sp. M8, aiming to assess the potential impact of different extractions on current microalgal lipid research. These methods included classical Bligh & Dyer lipid extraction, two other chemical extractions using different solvents and sonication, direct saponification and supercritical CO2 extraction. Soxhlet-based extraction was used to weigh out the importance of solvent polarity in the algal oil extraction. Coupled with GC/MS, a Thermogravimetric Analyser was used to improve the quantification of microalgal lipid extractions. Among these extractions, significant differences were observed in both, extract yield and fatty acid composition. The supercritical extraction technique stood out most for effective extraction of microalgal lipids, especially for long chain unsaturated fatty acids. The results highlight the necessity for comparative analyses of microalgae fatty acids and careful choice and validation of analytical methodology in microalgal lipid research. PMID:24456581

  20. Introduction to fatty acids and lipids.

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    Burdge, Graham C; Calder, Philip C

    2015-01-01

    The purpose of this article is to describe the structure, function and metabolism of fatty acids and lipids that are of particular importance in the context of parenteral nutrition. Lipids are a heterogeneous group of molecules that share the common property of hydrophobicity. Lipids range in structure from simple short hydrocarbon chains to more complex molecules, including triacylglycerols, phospholipids and sterols and their esters. Lipids within each class may differ structurally. Fatty acids are common components of complex lipids, and these differ according to chain length and the presence, number and position of double bonds in the hydrocarbon chain. Structural variation among complex lipids and among fatty acids gives rise to functional differences that result in different impacts upon metabolism and upon cell and tissue responses. Fatty acids and complex lipids exhibit a variety of structural variations that influence their metabolism and their functional effects. © 2015 S. Karger AG, Basel.

  1. Spontaneous charged lipid transfer between lipid vesicles.

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    Richens, Joanna L; Tyler, Arwen I I; Barriga, Hanna M G; Bramble, Jonathan P; Law, Robert V; Brooks, Nicholas J; Seddon, John M; Ces, Oscar; O'Shea, Paul

    2017-10-03

    An assay to study the spontaneous charged lipid transfer between lipid vesicles is described. A donor/acceptor vesicle system is employed, where neutrally charged acceptor vesicles are fluorescently labelled with the electrostatic membrane probe Fluoresceinphosphatidylethanolamine (FPE). Upon addition of charged donor vesicles, transfer of negatively charged lipid occurs, resulting in a fluorescently detectable change in the membrane potential of the acceptor vesicles. Using this approach we have studied the transfer properties of a range of lipids, varying both the headgroup and the chain length. At the low vesicle concentrations chosen, the transfer follows a first-order process where lipid monomers are transferred presumably through the aqueous solution phase from donor to acceptor vesicle. The rate of transfer decreases with increasing chain length which is consistent with energy models previously reported for lipid monomer vesicle interactions. Our assay improves on existing methods allowing the study of a range of unmodified lipids, continuous monitoring of transfer and simplified experimental procedures.

  2. Lipid nanotechnologies for structural studies of membrane-associated proteins.

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    Stoilova-McPhie, Svetla; Grushin, Kirill; Dalm, Daniela; Miller, Jaimy

    2014-11-01

    We present a methodology of lipid nanotubes (LNT) and nanodisks technologies optimized in our laboratory for structural studies of membrane-associated proteins at close to physiological conditions. The application of these lipid nanotechnologies for structure determination by cryo-electron microscopy (cryo-EM) is fundamental for understanding and modulating their function. The LNTs in our studies are single bilayer galactosylceramide based nanotubes of ∼20 nm inner diameter and a few microns in length, that self-assemble in aqueous solutions. The lipid nanodisks (NDs) are self-assembled discoid lipid bilayers of ∼10 nm diameter, which are stabilized in aqueous solutions by a belt of amphipathic helical scaffold proteins. By combining LNT and ND technologies, we can examine structurally how the membrane curvature and lipid composition modulates the function of the membrane-associated proteins. As proof of principle, we have engineered these lipid nanotechnologies to mimic the activated platelet's phosphtaidylserine rich membrane and have successfully assembled functional membrane-bound coagulation factor VIII in vitro for structure determination by cryo-EM. The macromolecular organization of the proteins bound to ND and LNT are further defined by fitting the known atomic structures within the calculated three-dimensional maps. The combination of LNT and ND technologies offers a means to control the design and assembly of a wide range of functional membrane-associated proteins and complexes for structural studies by cryo-EM. The presented results confirm the suitability of the developed methodology for studying the functional structure of membrane-associated proteins, such as the coagulation factors, at a close to physiological environment. © 2014 Wiley Periodicals, Inc.

  3. Experimental study of Pinus densiflora Siebold et Zuccarini on Hyperlipidemia and lipid in Rats

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    Kim, Dae-Hyun

    2007-02-01

    Full Text Available In order to study the effects of Pinus densiflora on hyperlipidemia and lipid in rats, we divided the rats into groups(Normal group, Control group and Sample group and perfomed the experimental research. Hyperlipidemia and lipid in rats were induced by high fat diets for 8weeks. The sample group was administerd the extract of Pinus densiflora for 14 days and control group was administerd equal dose of oral. And then we measured the amount of serum triglyceride, Total cholesterol, LDL-cholesterol, HDL-cholesterol, Free Fatty Acid, phospholipid, Insuline, Laptin, Body weight, epididymis fat weight & rate, epididymis fat cell, Cardiac Risk Factor(CRF. The results were as followers : 1. Sample Group showed decreasing effects on Total cholesterol, Trigylceride, LDL-cholesterol, and Phospholipid levels in serum and CRF significantly. 2. Sample Group showed increasing effects on HDL-cholesterol level in serum significantly. 3. Sample Group showed decreasing effects on Insuline in serum significantly. 4. Sample Group showed increasing effects on Laptin in serum significantly. 5. Sample Group showed decreasing effects on Body weight, epididymis fat weight & rate, epididymis fat cell significantly. According to the above results, Pinus densiflora showed significant decreasing effects on hyperlipidemia and lipid in rats, it is considered that it is appropriate to apply for hyperlipidemia, obesity.

  4. Outcomes of combined cardiovascular risk factor management strategies in type 2 diabetes: the ACCORD randomized trial.

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    Margolis, Karen L; O'Connor, Patrick J; Morgan, Timothy M; Buse, John B; Cohen, Robert M; Cushman, William C; Cutler, Jeffrey A; Evans, Gregory W; Gerstein, Hertzel C; Grimm, Richard H; Lipkin, Edward W; Narayan, K M Venkat; Riddle, Matthew C; Sood, Ajay; Goff, David C

    2014-06-01

    To compare effects of combinations of standard and intensive treatment of glycemia and either blood pressure (BP) or lipids in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. ACCORD enrolled 10,251 type 2 diabetes patients aged 40-79 years at high risk for cardiovascular disease (CVD) events. Participants were randomly assigned to hemoglobin A1c goals of risk of the primary outcome was lower in the groups intensively treated for glycemia (hazard ratio [HR] 0.67; 95% CI 0.50-0.91), BP (HR 0.74; 95% CI 0.55-1.00), or both (HR 0.71; 95% CI 0.52-0.96) compared with combined standard BP and glycemia treatment. For secondary outcomes, MI was significantly reduced by intensive glycemia treatment and stroke by intensive BP treatment; most other HRs were neutral or favored intensive treatment groups. In the lipid trial, the general pattern of results showed no evidence of benefit of intensive regimens (whether single or combined) compared with combined standard lipid and glycemia treatment. The mortality HR was 1.33 (95% CI 1.02-1.74) in the standard lipid/intensive glycemia group compared with the standard lipid/standard glycemia group. In the ACCORD BP trial, compared with combined standard treatment, intensive BP or intensive glycemia treatment alone improved major CVD outcomes, without additional benefit from combining the two. In the ACCORD lipid trial, neither intensive lipid nor glycemia treatment produced an overall benefit, but intensive glycemia treatment increased mortality. © 2014 by the American Diabetes Association.

  5. Study on mechanism of decreased lipid peroxide by low dose radiation

    International Nuclear Information System (INIS)

    Yamaoka, Kiyonori; Okazoe, Yoko; Akimaru, Kunihiro; Sato, E.F.; Utsumi, Kozo.

    1991-01-01

    We examined the effect of SOD on lipid peroxidation in biomembrane from V.E-deficient rats, in order to study the mechanism of increased SOD activities and decreased lipid peroxide by low dose irradiation. The following results were obtained. i. Active oxygen (O 2 - ) strongly enhances lipid peroxidations in biomembrane with the Fe 3+ as catalyst. ii. SOD evidently inhibits lipid peroxidations under above conditions. iii. We suggested that the effect of SOD enhanced by low dose irradiation results in inhibition of lipid peroxidation. (author)

  6. Reasons of general practitioners for not prescribing lipid-lowering medication to patients with diabetes: a qualitative study

    Directory of Open Access Journals (Sweden)

    AB Elisabeth

    2009-04-01

    Full Text Available Abstract Background Lipid-lowering medication remains underused, even in high-risk populations. The objective of this study was to determine factors underlying general practitioners' decisions not to prescribe such drugs to patients with type 2 diabetes. Methods A qualitative study with semi-structured interviews using real cases was conducted to explore reasons for not prescribing lipid-lowering medication after a guideline was distributed that recommended the use of statins in most patients with type 2 diabetes. Seven interviews were conducted with general practitioners (GPs in The Netherlands, and analysed using an analytic inductive approach. Results Reasons for not-prescribing could be divided into patient and physician-attributed factors. According to the GPs, some patients do not follow-up on agreed medication and others object to taking lipid-lowering medication, partly for legitimate reasons such as expected or perceived side effects. Furthermore, the GPs themselves perceived reservations for prescribing lipid-lowering medication in patients with short life expectancy, expected compliance problems or near goal lipid levels. GPs sometimes postponed the start of treatment because of other priorities. Finally, barriers were seen in the GPs' practice organisation, and at the primary-secondary care interface. Conclusion Some of the barriers mentioned by GPs seem to be valid reasons, showing that guideline non-adherence can be quite rational. On the other hand, treatment quality could improve by addressing issues, such as lack of knowledge or motivation of both the patient and the GP. More structured management in general practice may also lead to better treatment.

  7. Lipids, lipid bilayers and vesicles as seen by neutrons

    International Nuclear Information System (INIS)

    Seto, Hideki

    2011-01-01

    Lipid molecules self-assemble into bilayers in water with their hydrocarbon chains facing inward due to their amphiphilic nature. The structural and dynamical properties of lipids and lipid bilayers have been studied by neutron scattering intensively. In this article, 3 topics are shown as typical examples. 1) a time-resolved small-angle neutron scattering on uni-lamellar vesicles composed of deuterated and protonated lipids to determine lipid kinetics, 2) small-angle neutron scattering to investigate spontaneous formation of nanopores on uni-lamellar vesicles, and 3) neutron spin echo study to determine bending modulus of lipid bilayers. (author)

  8. Reconstitution of a Kv channel into lipid membranes for structural and functional studies.

    Science.gov (United States)

    Lee, Sungsoo; Zheng, Hui; Shi, Liang; Jiang, Qiu-Xing

    2013-07-13

    To study the lipid-protein interaction in a reductionistic fashion, it is necessary to incorporate the membrane proteins into membranes of well-defined lipid composition. We are studying the lipid-dependent gating effects in a prototype voltage-gated potassium (Kv) channel, and have worked out detailed procedures to reconstitute the channels into different membrane systems. Our reconstitution procedures take consideration of both detergent-induced fusion of vesicles and the fusion of protein/detergent micelles with the lipid/detergent mixed micelles as well as the importance of reaching an equilibrium distribution of lipids among the protein/detergent/lipid and the detergent/lipid mixed micelles. Our data suggested that the insertion of the channels in the lipid vesicles is relatively random in orientations, and the reconstitution efficiency is so high that no detectable protein aggregates were seen in fractionation experiments. We have utilized the reconstituted channels to determine the conformational states of the channels in different lipids, record electrical activities of a small number of channels incorporated in planar lipid bilayers, screen for conformation-specific ligands from a phage-displayed peptide library, and support the growth of 2D crystals of the channels in membranes. The reconstitution procedures described here may be adapted for studying other membrane proteins in lipid bilayers, especially for the investigation of the lipid effects on the eukaryotic voltage-gated ion channels.

  9. Molecular Transport Studies Through Unsupported Lipid Membranes

    Science.gov (United States)

    Rock, William; Parekh, Sapun; Bonn, Mischa

    2014-03-01

    Dendrimers, spherical polymeric nanoparticles made from branched monomers around a central core, show great promise as drug delivery vehicles. Dendrimer size, core contents, and surface functionality can be synthetically tuned, providing unprecedented versatility. Polyamidoamine (PAMAM) dendrimers have been shown to enter cells; however, questions remain about their biophysical interactions with the cell membrane, specifically about the presence and size of transient pores. We monitor dendrimer-lipid bilayer interactions using unsupported black lipid membranes (BLMs) as model cell membranes. Custom bilayer slides contain two vertically stacked aqueous chambers separated by a 25 μm Teflon sheet with a 120 μm aperture where the bilayer is formed. We vary the composition of model membranes (cholesterol content and lipid phase) to create biomimetic systems and study the interaction of PAMAM G6 and G3 dendrimers with these bilayers. Dendrimers, dextran cargo, and bilayers are monitored and quantified using time-lapse fluorescence imaging. Electrical capacitance measurements are simultaneously recorded to determine if the membrane is porous, and the pore size is deduced by monitoring transport of fluorescent dextrans of increasing molecular weight. These experiments shed light on the importance of cholesterol content and lipid phase on the interaction of dendrimer nanoparticles with membranes.

  10. Spin trapping studies of essential oils in lipid systems

    Directory of Open Access Journals (Sweden)

    Makarova Katerina

    2015-07-01

    Full Text Available In the present work, we report the results of a spin trapping ESR study of four essential oils widely used for skin care products such as creams and bath salts. The studied essential oils are Rosmarini aetheroleum (rosemary, Menthae piperitae aetheroleum (mint, Lavandulae aetheroleum (lavender, and Thymi aetheroleum (thyme. Fenton reaction in the presence of ethanol was used to generate free radicals. The N-tert-butyl-α-phenylnitrone (PBN was used as a spin trap. In the Fenton reaction, the rosemary oil had the lowest effect on radical adduct formation as compared to the reference Fenton system. Since essential oils are known to be lipid soluble, we also conducted studies of essential oils in Fenton reaction in the presence of lipids. Two model lipids were used, namely 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC. The obtained results suggested that in the presence of DOPC lipids, the •OH and PBN/•CHCH3(OH radicals are formed in both phases, that is, water and lipids, and all the studied essential oils affected the Fenton reaction in a similar way. Whereas, in the DPPC system, the additional type of PBN/X (aN = 16.1 G, aH = 2.9 G radical adduct was generated. DFT calculations of hyperfine splittings were performed at B3LYP/6-311+G(d,p/EPR-II level of theory for the set of c-centered PBN adducts in order to identify PBN/X radical.

  11. The Making and Taking of Lipids: The Role of Bacterial Lipid Synthesis and the Harnessing of Host Lipids in Bacterial Pathogenesis.

    Science.gov (United States)

    Fozo, E M; Rucks, E A

    2016-01-01

    In order to survive environmental stressors, including those induced by growth in the human host, bacterial pathogens will adjust their membrane physiology accordingly. These physiological changes also include the use of host-derived lipids to alter their own membranes and feed central metabolic pathways. Within the host, the pathogen is exposed to many stressful stimuli. A resulting adaptation is for pathogens to scavenge the host environment for readily available lipid sources. The pathogen takes advantage of these host-derived lipids to increase or decrease the rigidity of their own membranes, to provide themselves with valuable precursors to feed central metabolic pathways, or to impact host signalling and processes. Within, we review the diverse mechanisms that both extracellular and intracellular pathogens employ to alter their own membranes as well as their use of host-derived lipids in membrane synthesis and modification, in order to increase survival and perpetuate disease within the human host. Furthermore, we discuss how pathogen employed mechanistic utilization of host-derived lipids allows for their persistence, survival and potentiation of disease. A more thorough understanding of all of these mechanisms will have direct consequences for the development of new therapeutics, and specifically, therapeutics that target pathogens, while preserving normal flora. © 2016 Elsevier Ltd All rights reserved.

  12. Effects of conjugated estrogens/bazedoxifene on lipid and coagulation variables

    DEFF Research Database (Denmark)

    Skouby, Sven O; Pan, Kaijie; Thompson, John R

    2015-01-01

    OBJECTIVE: This study aims to evaluate the effects of conjugated estrogens (CE)/bazedoxifene (BZA) on lipid and coagulation variables in a randomized, double-blind, placebo- and active-controlled phase 3 study of nonhysterectomized postmenopausal women. METHODS: The Selective estrogens, Menopause......, And Response to Therapy (SMART)-5 trial evaluated the efficacy and safety of CE/BZA in postmenopausal women (N = 1,843) with menopausal symptoms. Lipid (N = 1,843) and coagulation (N = 590) variables were assessed in women receiving daily CE 0.45 mg/BZA 20 mg, CE 0.625 mg/BZA 20 mg, BZA 20 mg, CE 0.45 mg...... reassurance that CE/BZA does not adversely affect lipid metabolism or hemostatic balance. In accordance, the incidences of venous thromboembolic events and cardiovascular events in postmenopausal women are similar to those observed with placebo....

  13. Avanti lipid tools: connecting lipids, technology, and cell biology.

    Science.gov (United States)

    Sims, Kacee H; Tytler, Ewan M; Tipton, John; Hill, Kasey L; Burgess, Stephen W; Shaw, Walter A

    2014-08-01

    Lipid research is challenging owing to the complexity and diversity of the lipidome. Here we review a set of experimental tools developed for the seasoned lipid researcher, as well as, those who are new to the field of lipid research. Novel tools for probing protein-lipid interactions, applications for lipid binding antibodies, enhanced systems for the cellular delivery of lipids, improved visualization of lipid membranes using gold-labeled lipids, and advances in mass spectrometric analysis techniques will be discussed. Because lipid mediators are known to participate in a host of signal transduction and trafficking pathways within the cell, a comprehensive lipid toolbox that aids the science of lipidomics research is essential to better understand the molecular mechanisms of interactions between cellular components. This article is part of a Special Issue entitled Tools to study lipid functions. Copyright © 2014. Published by Elsevier B.V.

  14. LDL-cholesterol goal attainment under persistent lipid-lowering therapy in northeast China: Subgroup analysis of the dyslipidemia international study of China (DYSIS-China).

    Science.gov (United States)

    Zheng, Wen; Zhang, Yu-Jiao; Bu, Xiang-Ting; Guo, Xin-Zhu; Hu, Da-Yi; Li, Zhan-Quan; Sun, Jian

    2017-11-01

    Lipid-lowering therapy with statins reduces the risk of cardiovascular events, but the efficacy of persistent treatment in a real-world setting may vary from regions. Routine lipid-lowering therapy in the region with a high prevalence of cardiovascular disease may lead to more failures of goal attainment. We therefore performed a study to observe different lipid-lowering strategies in northeast (NE) China with respect to low-density lipoprotein-cholesterol (LDL-C) reduction and goal attainments.A cross-sectional study (DYSIS-China) was conducted in 2012, involving 25,317 patients from 122 centers across China who were diagnosed with hyperlipidemia and treated with lipid-lowering therapy for at least 3 months. Of these patients, 4559 (18.0%) were assigned to the NE group according to their residential zones.Patients in the NE group tended to be younger, female, overweight, and had more comorbidities and higher blood lipid levels than those in the non-NE group (P 24 kg/m, drinking alcohol, smoking, and being residence in NE China as independent predictors of LDL-C attainment.Despite having received persistent lipid-lowering treatments, the current situation of dyslipidemia patients in NE China is unsatisfactory. The main treatment gap might be related to the choice of statin and effective combination therapy and the control of comorbidities and obesity, especially for high-risk patients.

  15. A Novel Lipid Extraction Method from Wet Microalga Picochlorum sp. at Room Temperature

    Directory of Open Access Journals (Sweden)

    Fangfang Yang

    2014-03-01

    Full Text Available A novel method using ethanol was proposed for extracting lipids from wet microalga Picochlorum sp. at room temperature and pressure. In this study, Central Composite design (CCD was applied to investigate the optimum conditions of lipid extraction. The results revealed that the solvent to biomass ratio had the largest effect on lipid extraction efficiency, followed by extraction time and temperature. A high lipid extraction yield (33.04% of the dry weight was obtained under the following extraction conditions: 5 mL solvents per gram of wet biomass for 37 min with gentle stirring at room temperature. The extraction yield was comparable to that obtained by the widely used Bligh-Dyer method. Furthermore, no significant differences in the distribution of lipid classes and fatty acid composition were observed according to different extraction methods. In conclusion, these results indicated that the proposed procedure using ethanol could extract lipids from wet biomass efficiently and had giant potential for lipid extraction at large scale.

  16. Quantitative studies of antimicrobial peptide-lipid membrane interactions

    DEFF Research Database (Denmark)

    Kristensen, Kasper

    antimicrobial peptides interact with phospholipid membranes. Motivated by that fact, the scope of this thesis is to study these antimicrobial peptide-lipid membrane interactions. In particular, we attempt to study these interactions with a quantitative approach. For that purpose, we consider the three...... a significant problem for quantitative studies of antimicrobial peptide-lipid membrane interactions; namely that antimicrobial peptides adsorb to surfaces of glass and plastic. Specifically, we demonstrate that under standard experimental conditions, this effect is significant for mastoparan X, melittin...... lead to inaccurate conclusions, or even completely wrong conclusions, when interpreting the FCS data. We show that, if all of the pitfalls are avoided, then FCS is a technique with a large potential for quantitative studies of antimicrobial peptide-induced leakage of fluorescent markers from large...

  17. Lipids in citrus sinensis seeds

    International Nuclear Information System (INIS)

    Hamid, S.; Liaquat, L.; Khalid, B.; Khan, J.I.

    2003-01-01

    The seed oil of citrus sinensis when subjected to different physicochemical tests showed moisture 13.2%, ash 7.5%, ester value 1.29%, free fatty acid 0.4%. iodine value 65.0% and protein value 6.0%. According to lipid analysis. the oil was classified into hydrocarbons. wax esters, sterol esters, triglycerides. free fatty acids, 1,3 and 1,2 diglycerides, alcohols, sterols, monoglycerides, phosphatidylethanolamines, phosphatidylcholines and lysophosphatidylethanolamines. The fatty acid (C/sub 12.0/ - C/sub 21.0/) composition of all lipid classes was determined with the help of thin layer and gas liquid chromatography. (author)

  18. Association of alcohol consumption with lipid profile in hypertensive men.

    Science.gov (United States)

    Park, Hyejin; Kim, Kisok

    2012-01-01

    Alcohol consumption is known to be closely related with alterations in blood lipid levels as well as in blood pressure. The objective of this study was to evaluate the association between alcohol consumption and blood lipid levels in hypertensive men. A cross-sectional study involving participants (n = 2014) aged 20-69 years from the Korea National Health and Nutrition Examination Survey, 1998-2009. Demographic characteristics, dietary intake and medical history were obtained from the participants by questionnaire, and lipid levels were determined by analysis of blood samples. After adjusting for demographic and dietary factors, alcohol consumption was negatively associated with risk of low high-density lipoprotein cholesterol [HDL-C; odds ratio (OR): 0.29, 95% confidence interval (CI): 0.22-0.40 in heavy (≥30 g/day) drinkers; P for trend consumption (OR: 2.04, 95% CI: 1.53-2.72 in heavy drinkers; P for trend consumption. These data suggest that alcohol consumption differentially affected lipid measures according to the amount of alcohol intake in hypertensive men.

  19. Drug loading to lipid-based cationic nanoparticles

    International Nuclear Information System (INIS)

    Cavalcanti, Leide P.; Konovalov, Oleg; Torriani, Iris L.; Haas, Heinrich

    2005-01-01

    Lipid-based cationic nanoparticles are a new promising option for tumor therapy, because they display enhanced binding and uptake at the neo-angiogenic endothelial cells, which a tumor needs for its nutrition and growth. By loading suitable cytotoxic compounds to the cationic carrier, the tumor endothelial and consequently also the tumor itself can be destroyed. For the development of such novel anti-tumor agents, the control of drug loading and drug release from the carrier matrix is essential. We have studied the incorporation of the hydrophobic anti-cancer agent Paclitaxel (PXL) into a variety of lipid matrices by X-Ray reflectivity measurements. Liposome suspensions from cationic and zwitterionic lipids, comprising different molar fractions of Paclitaxel, were deposited on planar glass substrates. After drying at controlled humidity, well ordered, oriented multilayer stacks were obtained, as proven by the presence of bilayer Bragg peaks to several orders in the reflectivity curves. The presence of the drug induced a decrease of the lipid bilayer spacing, and with an excess of drug, also Bragg peaks of drug crystals could be observed. From the results, insight into the solubility of Paclitaxel in the model membranes was obtained and a structural model of the organization of the drug in the membrane was derived. Results from subsequent pressure/area-isotherm and grazing incidence diffraction (GID) measurements performed with drug/lipid Langmuir monolayers were in accordance with these conjectures

  20. LipidPedia: a comprehensive lipid knowledgebase.

    Science.gov (United States)

    Kuo, Tien-Chueh; Tseng, Yufeng Jane

    2018-04-10

    Lipids are divided into fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, saccharolipids, sterols, prenol lipids and polyketides. Fatty acyls and glycerolipids are commonly used as energy storage, whereas glycerophospholipids, sphingolipids, sterols and saccharolipids are common used as components of cell membranes. Lipids in fatty acyls, glycerophospholipids, sphingolipids and sterols classes play important roles in signaling. Although more than 36 million lipids can be identified or computationally generated, no single lipid database provides comprehensive information on lipids. Furthermore, the complex systematic or common names of lipids make the discovery of related information challenging. Here, we present LipidPedia, a comprehensive lipid knowledgebase. The content of this database is derived from integrating annotation data with full-text mining of 3,923 lipids and more than 400,000 annotations of associated diseases, pathways, functions, and locations that are essential for interpreting lipid functions and mechanisms from over 1,400,000 scientific publications. Each lipid in LipidPedia also has its own entry containing a text summary curated from the most frequently cited diseases, pathways, genes, locations, functions, lipids and experimental models in the biomedical literature. LipidPedia aims to provide an overall synopsis of lipids to summarize lipid annotations and provide a detailed listing of references for understanding complex lipid functions and mechanisms. LipidPedia is available at http://lipidpedia.cmdm.tw. yjtseng@csie.ntu.edu.tw. Supplementary data are available at Bioinformatics online.

  1. Synthesis, activity, and structure--activity relationship studies of novel cationic lipids for DNA transfer.

    Science.gov (United States)

    Byk, G; Dubertret, C; Escriou, V; Frederic, M; Jaslin, G; Rangara, R; Pitard, B; Crouzet, J; Wils, P; Schwartz, B; Scherman, D

    1998-01-15

    We have designed and synthesized original cationic lipids for gene delivery. A synthetic method on solid support allowed easy access to unsymmetrically monofunctionalized polyamine building blocks of variable geometries. These polyamine building blocks were introduced into cationic lipids. To optimize the transfection efficiency in the novel series, we have carried out structure-activity relationship studies by introduction of variable-length lipids, of variable-length linkers between lipid and cationic moiety, and of substituted linkers. We introduce the concept of using the linkers within cationic lipids molecules as carriers of side groups harboring various functionalities (side chain entity), as assessed by the introduction of a library composed of cationic entities, additional lipid chains, targeting groups, and finally the molecular probes rhodamine and biotin for cellular traffic studies. The transfection activity of the products was assayed in vitro on Hela carcinoma, on NIH3T3, and on CV1 fibroblasts and in vivo on the Lewis Lung carcinoma model. Products from the series displayed high transfection activities. Results indicated that the introduction of a targeting side chain moiety into the cationic lipid is permitted. A primary physicochemical characterization of the DNA/lipid complexes was demonstrated with this leading compound. Selected products from the series are currently being developed for preclinical studies, and the labeled lipopolyamines can be used to study the intracellular traffic of DNA/cationic lipid complexes.

  2. Diclofenac salts, part 6: release from lipid microspheres.

    Science.gov (United States)

    Fini, Adamo; Cavallari, Cristina; Rabasco Alvarez, Antonio M; Rodriguez, Marisa Gonzalez

    2011-08-01

    The release of diclofenac (20%, w/w) was studied from lipidic solid dispersions using three different chemical forms (acid, sodium salt, and pyrrolidine ethanol salt) and two different lipid carriers (Compritol 888 ATO or Carnauba wax) either free or together with varying amounts (10%-30%, w/w) of stearic acid. Microspheres were prepared by ultrasound-assisted atomization of the molten dispersions and analyzed by scanning electron microscopy, differential scanning calorimetry, and hot stage microscopy. The effects of different formulations on the resulting drug release profiles as a function of pH were studied and the results were discussed. The formulation of the 18 systems and the chemical form of the drug were found to strongly affect the mode of the drug release. The solubility of the chemical forms in the lipid mixture is in the following order: pyrrolidine ethanol salt ≫ acid > sodium salt (according to the solubility parameters), and the nature of the systems thus obtained ranges from a matrix, for mutually soluble drug/carrier pairs, to a microcapsule, for pairs wherein mutual solubility is poor. Drug release from microspheres prepared by pure lipids was primarily controlled by diffusion, whereas the release from microspheres containing stearic acid was diffusion/erosion controlled at pH 7.4. Copyright © 2011 Wiley-Liss, Inc.

  3. MOLECULAR DYNAMICS STUDY OF CYTOCHROME C – LIPID COMPLEXES

    Directory of Open Access Journals (Sweden)

    V. Trusova

    2017-10-01

    Full Text Available The interactions between a mitochondrial hemoprotein cytochrome c (cyt c and the model lipid membranes composed of zwitterionic lipid phosphatidylcholine (PC and anionic lipids phosphatidylglycerol (PG, phosphatidylserine (PS or cardiolipin (CL were studied using the method of molecular dynamics. It was found that cyt c structure remains virtually unchanged in the protein complexes with PC/PG or PC/PS bilayers. In turn, protein binding to PC/CL bilayer is followed by the rise in cyt c radius of gyration and root-mean-square fluctuations. The magnitude of these changes was demonstrated to increase with the anionic lipid content. The revealed effect was interpreted in terms of the partial unfolding of polypeptide chain in the region Ala15-Leu32, widening of the heme crevice and enhancement of the conformational fluctuations in the region Pro76-Asp93 upon increasing the CL molar fraction from 5 to 25%. The results obtained seem to be of utmost importance in the context of amyloidogenic propensity of cyt c.

  4. Serum lipid profile in alcoholic cirrhosis: A study in a teaching ...

    African Journals Online (AJOL)

    However, there are only a few studies regarding lipid profile in alcoholic cirrhosis that have been undertaken in India. The aim of the study is to assess the degree of alteration of serum lipid profile in alcoholic cirrhotic patients and also to detect its relationship with the age of the patients and the alcohol consumption pattern.

  5. Atomistic study of lipid membranes containing chloroform: looking for a lipid-mediated mechanism of anesthesia.

    Directory of Open Access Journals (Sweden)

    Ramon Reigada

    Full Text Available The molecular mechanism of general anesthesia is still a controversial issue. Direct effect by linking of anesthetics to proteins and indirect action on the lipid membrane properties are the two hypotheses in conflict. Atomistic simulations of different lipid membranes subjected to the effect of small volatile organohalogen compounds are used to explore plausible lipid-mediated mechanisms. Simulations of homogeneous membranes reveal that electrostatic potential and lateral pressure transversal profiles are affected differently by chloroform (anesthetic and carbon tetrachloride (non-anesthetic. Simulations of structured membranes that combine ordered and disordered regions show that chloroform molecules accumulate preferentially in highly disordered lipid domains, suggesting that the combination of both lateral and transversal partitioning of chloroform in the cell membrane could be responsible of its anesthetic action.

  6. Proteins mediating intra- and intercellular transport of lipids and lipid-modified proteins

    NARCIS (Netherlands)

    Neumann, S.

    2008-01-01

    Proteins mediating intra- and intercellular transport of lipids and lipid-modified proteins In this thesis, I studied the intra- and intercellular transport of lipidic molecules, in particular glycosphingolipids and lipid-modified proteins. The first part focuses on the intracellular transport of

  7. Lipid Structure in Triolein Lipid Droplets

    DEFF Research Database (Denmark)

    Chaban, Vitaly V; Khandelia, Himanshu

    2014-01-01

    of a mass of hydrophobic lipid esters coved by phospholipid monolayer. The small size and unique architecture of LDs makes it complicated to study LD structure by modern experimental methods. We discuss coarse-grained molecular dynamics (MD) simulations of LD formation in systems containing 1-palmitoyl-2...... to coarse-grained simulations, the presence of PE lipids at the interface has a little impact on distribution of components and on the overall LD structure. (4) The thickness of the lipid monolayer at the surface of the droplet is similar to the thickness of one leaflet of a bilayer. Computer simulations......Lipid droplets (LDs) are primary repositories of esterified fatty acids and sterols in animal cells. These organelles originate on the lumenal or cytoplasmic side of endoplasmic reticulum (ER) membrane and are released to the cytosol. In contrast to other intracellular organelles, LDs are composed...

  8. Structural studies of the lipid membranes at the Siberia-2 synchrotron radiation source

    International Nuclear Information System (INIS)

    Kiselev, M. A.; Ermakova, E. V.; Ryabova, N. Yu.; Nayda, O. V.; Zabelin, A. V.; Pogorely, D. K.; Korneev, V. N.; Balagurov, A. M.

    2010-01-01

    Lipid membranes are a subject of contemporary interdisciplinary studies at the junction of biology, biophysics, pharmacology, and bionanotechnology. The results of the structural studies of several types of lipid membranes by the lamellar and lateral diffraction of X-ray synchrotron radiation are presented. The experiments were performed at the Mediana and DICSI stations of the Siberia-2 synchrotron radiation source at the Russian Research Center Kurchatov Institute. The data obtained are compared with the results of studying lipid membranes at the small-angle scattering beamlines D22 and D24 at LURE (France) and at the A2 beamline at DESY (Germany). The parameters of the DICSI station are shown to meet the basic requirements for the structural study of lipid systems, which are of fundamental and applied interest.

  9. Characterization of lipid rafts in human platelets using nuclear magnetic resonance: A pilot study

    Directory of Open Access Journals (Sweden)

    Joshua F. Ceñido

    2017-07-01

    Full Text Available Lipid microdomains (‘lipid rafts’ are plasma membrane subregions, enriched in cholesterol and glycosphingolipids, which participate dynamically in cell signaling and molecular trafficking operations. One strategy for the study of the physicochemical properties of lipid rafts in model membrane systems has been the use of nuclear magnetic resonance (NMR, but until now this spectroscopic method has not been considered a clinically relevant tool. We performed a proof-of-concept study to test the feasibility of using NMR to study lipid rafts in human tissues. Platelets were selected as a cost-effective and minimally invasive model system in which lipid rafts have previously been studied using other approaches. Platelets were isolated from plasma of medication-free adult research participants (n=13 and lysed with homogenization and sonication. Lipid-enriched fractions were obtained using a discontinuous sucrose gradient. Association of lipid fractions with GM1 ganglioside was tested using HRP-conjugated cholera toxin B subunit dot blot assays. 1H high resolution magic-angle spinning nuclear magnetic resonance (HRMAS NMR spectra obtained with single-pulse Bloch decay experiments yielded spectral linewidths and intensities as a function of temperature. Rates of lipid lateral diffusion that reported on raft size were measured with a two-dimensional stimulated echo longitudinal encode-decode NMR experiment. We found that lipid fractions at 10–35% sucrose density associated with GM1 ganglioside, a marker for lipid rafts. NMR spectra of the membrane phospholipids featured a prominent ‘centerband’ peak associated with the hydrocarbon chain methylene resonance at 1.3 ppm; the linewidth (full width at half-maximum intensity of this ‘centerband’ peak, together with the ratio of intensities between the centerband and ‘spinning sideband’ peaks, agreed well with values reported previously for lipid rafts in model membranes. Decreasing

  10. Supercritical fluid chromatography for lipid analysis in foodstuffs.

    Science.gov (United States)

    Donato, Paola; Inferrera, Veronica; Sciarrone, Danilo; Mondello, Luigi

    2017-01-01

    The task of lipid analysis has always challenged separation scientists, and new techniques in chromatography were often developed for the separation of lipids; however, no single technique or methodology is yet capable of affording a comprehensive screening of all lipid species and classes. This review acquaints the role of supercritical fluid chromatography within the field of lipid analysis, from the early developed capillary separations based on pure CO 2 , to the most recent techniques employing packed columns under subcritical conditions, including the niche multidimensional techniques using supercritical fluids in at least one of the separation dimensions. A short history of supercritical fluid chromatography will be introduced first, from its early popularity in the late 1980s, to the sudden fall and oblivion until the last decade, experiencing a regain of interest within the chromatographic community. Afterwards, the subject of lipid nomenclature and classification will be briefly dealt with, before discussing the main applications of supercritical fluid chromatography for food analysis, according to the specific class of lipids. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Simulation studies of protein-induced bilayer deformations, and lipid-induced protein tilting, on a mesoscopic model for lipid bilayers with embedded proteins

    DEFF Research Database (Denmark)

    Venturoli, M.; Smit, B.; Sperotto, Maria Maddalena

    2005-01-01

    membranes. Here we present a mesoscopic model for lipid bilayers with embedded proteins, which we have studied with the help of the dissipative particle dynamics simulation technique. Because hydrophobic matching is believed to be one of the main physical mechanisms regulating lipid-protein interactions......-induced protein tilt, with the hydrophobic mismatch ( positive and negative) between the protein hydrophobic length and the pure lipid bilayer hydrophobic thickness. The protein-induced bilayer perturbation was quantified in terms of a coherence length, xi(P), of the lipid bilayer hydrophobic thickness pro. le...... for positive values of mismatch; a dependence on the protein size appears as well. In the case of large model proteins experiencing extreme mismatch conditions, in the region next to the so-called lipid annulus, there appears an undershooting ( or overshooting) region where the bilayer hydrophobic thickness...

  12. Physical activity, sedentary behavior time and lipid levels in the Observation of Cardiovascular Risk Factors in Luxembourg study.

    Science.gov (United States)

    Crichton, Georgina E; Alkerwi, Ala'a

    2015-08-11

    Recently attention has been drawn to the health impacts of time spent engaging in sedentary behaviors. While many studies have investigated general physical activity (PA) in relation to blood lipid levels, the current study aimed to examine the intensity of activity, including sedentary behavior time, and time spent engaging in moderate and intense PA, with concentrations of HDL and LDL-cholesterol, total cholesterol, and triglycerides. Participants comprised 1331 individuals, aged 18 to 70 years, from the Observation of Cardiovascular Risk Factors in Luxembourg (ORISCAV-LUX) study, who underwent objective cardiovascular health assessments and completed the International Physical Activity Questionnaire (IPAQ). Time spent engaging in sedentary behaviors (screen time on a workday and a day off, and total sitting time on a work day), and moderate and intense PA, were related to levels of HDL and LDL-cholesterol, total cholesterol, and triglycerides. Analyses were conducted in the whole sample, and then with stratification according to BMI (normal weight versus overweight/obese). Both lower screen time during days off and higher intense PA time were significantly associated with higher HDL-cholesterol after full adjustment for socio-demographic factors, dietary factors and smoking (both p sedentary behavior time variables were observed (all p sedentary behavior time variable and lipid levels in those overweight or obese. Spending less time in sedentary behaviors, and engaging in medium levels of intense physical activity may be associated with a more favorable blood lipid profile, particularly with regard to levels of HDL and triglycerides.

  13. Betatrophin provides a new insight into diabetes treatment and lipid metabolism (Review).

    Science.gov (United States)

    Zhu, Jin-Zhou; Yu, Chao-Hui; Li, You-Ming

    2014-07-01

    Replenishing the insulin-producing β-cell mass is considered to be a potential cure for diabetes. A recent study identified a secreted protein, known as betatrophin, which potently induces pancreatic β-cell proliferation. Notably, a number of studies reportedly identified betatrophin, which is also known as lipasin, atypical angiopoietin-like 8 and refeeding-induced fat and liver protein, and considered to be a novel regulator in lipid metabolism according to the studies. The identification of betatrophin was considered to create novel opportunities for potential diabetes therapy. In the present study, the current knowledge of betatrophin is reviewed, with regards to its character and function in lipid homeostasis and pancreatic β-cell proliferation.

  14. Maternal Diabetes Leads to Unphysiological High Lipid Accumulation in Rabbit Preimplantation Embryos

    NARCIS (Netherlands)

    Schindler, Maria; Pendzialek, Mareike; Santos, Alexander Navarrete; Ploesch, Torsten; Seyring, Stefanie; Guerke, Jacqueline; Haucke, Elisa; Knelangen, Julia Miriam; Fischer, Bernd; Santos, Anne Navarrete

    According to the "developmental origin of health and disease" hypothesis, the metabolic set points of glucose and lipid metabolism are determined prenatally. In the case of a diabetic pregnancy, the embryo is exposed to higher glucose and lipid concentrations as early as during preimplantation

  15. SFG studies on interactions between antimicrobial peptides and supported lipid bilayers.

    Science.gov (United States)

    Chen, Xiaoyun; Chen, Zhan

    2006-09-01

    The mode of action of antimicrobial peptides (AMPs) in disrupting cell membrane bilayers is of fundamental importance in understanding the efficiency of different AMPs, which is crucial to design antibiotics with improved properties. Recent developments in the field of sum frequency generation (SFG) vibrational spectroscopy have made it a powerful and unique biophysical technique in investigating the interactions between AMPs and a single substrate supported planar lipid bilayer. We will review some of the recent progress in applying SFG to study membrane lipid bilayers and discuss how SFG can provide novel information such as real-time bilayer structure change and AMP orientation during AMP-lipid bilayer interactions in a very biologically relevant manner. Several examples of applying SFG to monitor such interactions between AMPs and a dipalmitoyl phosphatidylglycerol (DPPG) bilayer are presented. Different modes of actions are observed for melittin, tachyplesin I, d-magainin 2, MSI-843, and a synthetic antibacterial oligomer, demonstrating that SFG is very effective in the study of AMPs and AMP-lipid bilayer interactions.

  16. A COMPARATIVE STUDY OF LIPID PROFILE IN SEDENTARY AND ACTIVE ADULT FEMALES

    Directory of Open Access Journals (Sweden)

    Suhasini Sanda

    2018-11-01

    Full Text Available BACKGROUND Lipids and lipoproteins are essential constituents of the body and their activities assist in maintenance of body homeostasis. Sedentary lifestyle has been shown to lead to inactivity, which could lead to lipid disorders. Hyperlipidaemias is one of the major independent risk factor, which affects the cardiovascular system adversely resulting eventually damage to various organs most notably heart, kidneys and brain. The present study is therefore designed to ascertain the effect of sedentary lifestyle on lipid status of sedentary adult females when compared to that of the lipid status of active adult females. MATERIALS AND METHODS The present study comprised of Group I - 50 sedentary adult females and Group II - 50 active adult females aged between 30 to 60 years. The subjects selected in both groups were matched for age and dietary habits. The subjects with hypertension, diabetes, smokers, pregnancy and subjects with Body Mass Index (BMI greater than 30 are excluded. After overnight fasting of 12 to 14 hours, 5 mL of blood is collected from the subjects and fasting Total Serum Cholesterol (TC, Total Serum Triglycerides (TG, HDL cholesterol (HDL-C, LDL cholesterol (LDL-C and total serum cholesterol/HDL-C ratio are measured and data is statistically analysed. RESULTS The evaluation of lipid profile patterns in above subjects showed hypercholesterolaemia, hypertriglyceridaemia, increased LDLC and total serum cholesterol/HDL-C ratio in sedentary adult females and also decreased HDL-C levels in them when compared to the normal healthy lipid profile patterns in active adult females. A statistically significant increased lipid profiles (P-value <0.001 was observed in the sedentary adult females than in active adult females. CONCLUSION This study shows that sedentary lifestyle predisposes to hyperlipidaemias, one of the major risk factor of cardiovascular disease and lack of exercise worsens the situation.

  17. A Molecular Dynamics Study of the Structural and Dynamical Properties of Putative Arsenic Substituted Lipid Bilayers

    Directory of Open Access Journals (Sweden)

    Ratna Juwita

    2013-04-01

    Full Text Available Cell membranes are composed mainly of phospholipids which are in turn, composed of five major chemical elements: carbon, hydrogen, nitrogen, oxygen, and phosphorus. Recent studies have suggested the possibility of sustaining life if the phosphorus is substituted by arsenic. Although this issue is still controversial, it is of interest to investigate the properties of arsenated-lipid bilayers to evaluate this possibility. In this study, we simulated arsenated-lipid, 1-palmitoyl-2-oleoyl-sn-glycero-3-arsenocholine (POAC, lipid bilayers using all-atom molecular dynamics to understand basic structural and dynamical properties, in particular, the differences from analogous 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, (POPC lipid bilayers. Our simulations showed that POAC lipid bilayers have distinct structural and dynamical properties from those of native POPC lipid bilayers. Relative to POPC lipid bilayers, POAC lipid bilayers have a more compact structure with smaller lateral areas and greater order. The compact structure of POAC lipid bilayers is due to the fact that more inter-lipid salt bridges are formed with arsenate-choline compared to the phosphate-choline of POPC lipid bilayers. These inter-lipid salt bridges bind POAC lipids together and also slow down the head group rotation and lateral diffusion of POAC lipids. Thus, it would be anticipated that POAC and POPC lipid bilayers would have different biological implications.

  18. SERUM LIPID PROFILE AS AN ETIOLOGY OF VERTIGO : A STUDY

    Directory of Open Access Journals (Sweden)

    Sami

    2015-09-01

    Full Text Available A prospective study of lipid profile was done in 60 patients of vertigo at E.L.M.C. Lucknow from 2011 to 2014. All components of serum cholesterol were analyzed. Serum cholesterol and hyperlipidemia as an etiology of the atherosclerosis of all blood vessel s also have a role in vestibulo - cochlear vessels. It was found that there were 34 females and 26 males and maximum number of patients (63.33% in the age group of 31 - 50years. Appreciable difference (p<0.05 in the mean value of total lipid, total cholester ol, triglycerides and phospholipids in the control and study group was found but difference was not significant in the mean value of HDL, LDL and VLDL cholesterol level. Four cases of diabetes and ten cases of hypertension of 60 vertigo cases were having m arked vertigo of longer duration. These findings were similar to Mehra Y.N. Thus we find that serum lipid studies are important in the patients of vertigo for the diagnosis and management

  19. Astrocyte lipid metabolism is critical for synapse development and function in vivo.

    Science.gov (United States)

    van Deijk, Anne-Lieke F; Camargo, Nutabi; Timmerman, Jaap; Heistek, Tim; Brouwers, Jos F; Mogavero, Floriana; Mansvelder, Huibert D; Smit, August B; Verheijen, Mark H G

    2017-04-01

    The brain is considered to be autonomous in lipid synthesis with astrocytes producing lipids far more efficiently than neurons. Accordingly, it is generally assumed that astrocyte-derived lipids are taken up by neurons to support synapse formation and function. Initial confirmation of this assumption has been obtained in cell cultures, but whether astrocyte-derived lipids support synapses in vivo is not known. Here, we address this issue and determined the role of astrocyte lipid metabolism in hippocampal synapse formation and function in vivo. Hippocampal protein expression for the sterol regulatory element-binding protein (SREBP) and its target gene fatty acid synthase (Fasn) was found in astrocytes but not in neurons. Diminishing SREBP activity in astrocytes using mice in which the SREBP cleavage-activating protein (SCAP) was deleted from GFAP-expressing cells resulted in decreased cholesterol and phospholipid secretion by astrocytes. Interestingly, SCAP mutant mice showed more immature synapses, lower presynaptic protein SNAP-25 levels as well as reduced numbers of synaptic vesicles, indicating impaired development of the presynaptic terminal. Accordingly, hippocampal short-term and long-term synaptic plasticity were defective in mutant mice. These findings establish a critical role for astrocyte lipid metabolism in presynaptic terminal development and function in vivo. GLIA 2017;65:670-682. © 2017 Wiley Periodicals, Inc.

  20. Effect of conventional cooking methods on lipid oxidation indices in lamb meat

    Directory of Open Access Journals (Sweden)

    A Pourkhalili

    2012-05-01

    Full Text Available Lipid oxidation is one of the most deteriorative reactions occurred in foodstuff which has harmful impacts on the both food quality and consumer's health. This study was designed to speculate the influence of three conventional cooking methods including boiling, frying and grilling on lipid oxidation parameters in cooked lamb meat. Sections of lamb meat from longissimus dorsi muscle, taken from native Lori-Bakhtiary sheep species were cut into uniform pieces and cooked using boiling, frying and roasting methods according to the cooking routine and tradition in Iranian society, in terms of temperature and time. Proximate compositions (moisture, lipid, ash and protein in the raw and cooked meat were determined using the standard methods of analysis. Moreover, weight loss was measured after each treatment. Lipid oxidation parameters such as peroxide value, conjugated diene and TBARS indices were measured in the raw and cooked samples. Evaluation of lipid oxidation parameters showed that peroxide value was significantly decreased in all cooked samples. In contrast, conjugated diene value was significantly increased in the fried and grilled samples (p

  1. Interaction pathways between soft lipid nanodiscs and plasma membranes: A molecular modeling study.

    Science.gov (United States)

    Li, Shixin; Luo, Zhen; Xu, Yan; Ren, Hao; Deng, Li; Zhang, Xianren; Huang, Fang; Yue, Tongtao

    2017-10-01

    Lipid nanodisc, a model membrane platform originally synthesized for study of membrane proteins, has recently been used as the carrier to deliver amphiphilic drugs into target tumor cells. However, the central question of how cells interact with such emerging nanomaterials remains unclear and deserves our research for both improving the delivery efficiency and reducing the side effect. In this work, a binary lipid nanodisc is designed as the minimum model to investigate its interactions with plasma membranes by using the dissipative particle dynamics method. Three typical interaction pathways, including the membrane attachment with lipid domain exchange of nanodiscs, the partial membrane wrapping with nanodisc vesiculation, and the receptor-mediated endocytosis, are discovered. For the first pathway, the boundary normal lipids acting as ligands diffuse along the nanodisc rim to gather at the membrane interface, repelling the central bola lipids to reach a stable membrane attachment. If bola lipids are positioned at the periphery and act as ligands, they diffuse to form a large aggregate being wrapped by the membrane, leaving the normal lipids exposed on the membrane exterior by assembling into a vesicle. Finally, by setting both central normal lipids and boundary bola lipids as ligands, the receptor-mediated endocytosis occurs via both deformation and self-rotation of the nanodiscs. All above pathways for soft lipid nanodiscs are quite different from those for rigid nanoparticles, which may provide useful guidelines for design of soft lipid nanodiscs in widespread biomedical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Atomic Force Microscopy Study on the Stiffness of Nanosized Liposomes Containing Charged Lipids.

    Science.gov (United States)

    Takechi-Haraya, Yuki; Goda, Yukihiro; Sakai-Kato, Kumiko

    2018-06-18

    It has recently been recognized that the mechanical properties of lipid nanoparticles play an important role during in vitro and in vivo behaviors such as cellular uptake, blood circulation, and biodistribution. However, there have been no quantitative investigations of the effect of commonly used charged lipids on the stiffness of nanosized liposomes. In this study, by means of atomic force microscopy (AFM), we quantified the stiffness of nanosized liposomes composed of neutrally charged lipids combined with positively or negatively charged lipids while simultaneously imaging the liposomes in aqueous medium. Our results showed that charged lipids, whether negatively or positively charged, have the effect of reducing the stiffness of nanosized liposomes, independently of the saturation degree of the lipid acyl chains; the measured stiffness values of liposomes containing charged lipids are 30-60% lower than those of their neutral counterpart liposomes. In addition, we demonstrated that the Laurdan generalized polarization values, which are related to the hydration degree of the liposomal membrane interface and often used as a qualitative indicator of liposomal membrane stiffness, do not directly correlate with the physical stiffness values of the liposomes prepared in this study. However, our results indicate that direct quantitative AFM measurement is a valuable method to gain molecular-scale information about how the hydration degree of liposomal interfaces reflects (or does not reflect) liposome stiffness as a macroscopic property. Our AFM method will contribute to the quantitative characterization of the nano-bio interaction of nanoparticles and to the optimization of the lipid composition of liposomes for clinical use.

  3. Lipid Status of the Two High Latitude Fish Species, Leptoclinus maculatus and Lumpenus fabricii

    Directory of Open Access Journals (Sweden)

    Nina N. Nemova

    2013-03-01

    Full Text Available A comparative study of the lipid status (i.e., the total lipid and phospholipid concentrations and the percentage of fatty acids of the total lipids of adult specimens of daubed shanny (Leptoclinus maculatus from Svalbard waters (Isfjord and slender eel blenny (Lumpenus fabricii from the White Sea (Onega Bay and Tersky shore was performed to study the metabolism and functions of lipids of these fishes in ontogeny and under various ecological conditions. Slender eel blenny from both areas of the White Sea were distinguished by a high level of sphingomyelin compared with the daubed shanny from Svalbard, and the amount of total phospholipids was higher in slender eel blenny from Onega Bay than in slender eel blenny from the Tersky shore. The extent of saturation and the signature of polyenic fatty acids varied according to the specific species of the Stichaeidae family under study. These results demonstrate the differences in the trophoecological and hydrobiological conditions of habitations of these species and highlighted the importance of considering certain trends in the lipid profiles of these fishes as specific features of the organization of the ecological and biochemical mechanisms of adaptation.

  4. Lipid drug conjugate nanoparticle as a novel lipid nanocarrier for the oral delivery of decitabine: ex vivo gut permeation studies

    International Nuclear Information System (INIS)

    Neupane, Yub Raj; Sabir, M D; Ahmad, Nafees; Ali, Mushir; Kohli, Kanchan

    2013-01-01

    The purpose of this study was to develop lipid drug conjugate (LDC) nanoparticles of decitabine (DCB) using stearic acid as a lipid to increase the permeability of the drug along with its protection from chemical degradation. The LDC was prepared by salt formation of DCB with stearic acid and followed by cold homogenization technique to produce the LDC nanoparticles. The role of key independent variables influencing on dependent variables were determined by using a Box–Behnken design. The optimized batch revealed spherical morphology under TEM analysis with particle size of 202.6 ± 1.65 nm and 0.334 ± 0.987 PDI. The zeta potential and %EE were found to be −33.6 ± 0.845 mV and 68.89% ± 0.59 respectively. Lyophilized powder showed the crystalline structure under DSC analysis. In vitro release studies showed the initial burst release followed by a sustained release up to 24 h in PBS pH 7.4 and the data were further studied using release kinetic models which revealed the first-order model as a best-fitting model. Ex vivo gut permeation studies proved that the formulation containing lipid and surfactants has a higher permeability than the plain drug solution with nearly fourfold increase in the apparent permeability coefficients. Finally, LDC nanoparticles prepared by using stearic acid as a lipid and surfactants as Tween 80, Poloxamer 188, and Labrasol in equal ratio possess high potential for the oral delivery of hydrophilic drugs. (paper)

  5. Lipid drug conjugate nanoparticle as a novel lipid nanocarrier for the oral delivery of decitabine: ex vivo gut permeation studies

    Science.gov (United States)

    Neupane, Yub Raj; Sabir, M. D.; Ahmad, Nafees; Ali, Mushir; Kohli, Kanchan

    2013-10-01

    The purpose of this study was to develop lipid drug conjugate (LDC) nanoparticles of decitabine (DCB) using stearic acid as a lipid to increase the permeability of the drug along with its protection from chemical degradation. The LDC was prepared by salt formation of DCB with stearic acid and followed by cold homogenization technique to produce the LDC nanoparticles. The role of key independent variables influencing on dependent variables were determined by using a Box-Behnken design. The optimized batch revealed spherical morphology under TEM analysis with particle size of 202.6 ± 1.65 nm and 0.334 ± 0.987 PDI. The zeta potential and %EE were found to be -33.6 ± 0.845 mV and 68.89% ± 0.59 respectively. Lyophilized powder showed the crystalline structure under DSC analysis. In vitro release studies showed the initial burst release followed by a sustained release up to 24 h in PBS pH 7.4 and the data were further studied using release kinetic models which revealed the first-order model as a best-fitting model. Ex vivo gut permeation studies proved that the formulation containing lipid and surfactants has a higher permeability than the plain drug solution with nearly fourfold increase in the apparent permeability coefficients. Finally, LDC nanoparticles prepared by using stearic acid as a lipid and surfactants as Tween 80, Poloxamer 188, and Labrasol in equal ratio possess high potential for the oral delivery of hydrophilic drugs.

  6. Neutron reflectivity studies of single lipid bilayers supported on planar substrates

    International Nuclear Information System (INIS)

    Krueger, S.; Orts, W.J.; Berk, N.F.; Majkrzak, C.F.; Koenig, B.W.

    1994-01-01

    Neutron reflectivity was used to probe the structure of single phosphatidylcholine (PC) lipid bilayers adsorbed onto a planar silicon surface in an aqueous environment. Fluctuations in the neutron scattering length density profiles perpendicular to the silicon/water interface were determined for different lipids as a function of the hydrocarbon chain length. The lipids were studied in both the gel and liquid crystalline phases by monitoring changes in the specularly-reflected neutron intensity as a function of temperature. Contrast variation of the neutron scattering length density was applied to both the lipid and the solvent. Scattering length density profiles were determined using both model-independent and model-dependent fitting methods. During the reflectivity measurements, a novel experimental set-up was implemented to decrease the incoherent background scattering due to the solvent. Thus, the reflectivity was measured to Q ∼ 0.3 Angstrom -1 , covering up to seven orders of magnitude in reflected intensity, for PC bilayers in D 2 O and silicon-matched (38% D 2 O/62% H 2 O) water. The kinetics of lipid adsorption at the silicon/water interface were also explored by observing changes in the reflectivity at low Q values under silicon-matched water conditions

  7. Polyene-lipids: a new tool to image lipids

    DEFF Research Database (Denmark)

    Kuerschner, Lars; Ejsing, Christer S.; Ekroos, Kim

    2005-01-01

    conjugated double bonds as a new type of lipid tag. Polyene-lipids exhibit a unique structural similarity to natural lipids, which results in minimal effects on the lipid properties. Analyzing membrane phase partitioning, an important biophysical and biological property of lipids, we demonstrated......Microscopy of lipids in living cells is currently hampered by a lack of adequate fluorescent tags. The most frequently used tags, NBD and BODIPY, strongly influence the properties of lipids, yielding analogs with quite different characteristics. Here, we introduce polyene-lipids containing five...... the superiority of polyene-lipids to both NBD- and BODIPY-tagged lipids. Cells readily take up various polyene-lipid precursors and generate the expected end products with no apparent disturbance by the tag. Applying two-photon excitation microscopy, we imaged the distribution of polyene-lipids in living...

  8. Lipid lowering treatment patterns and goal attainment in Nordic patients with hyperlipidemia

    DEFF Research Database (Denmark)

    Svilaas, A.; Strandberg, T.; Eriksson, M.

    2008-01-01

    OBJECTIVES: Observational studies and surveys have shown that lipid-lowering treatment is not optimal neither with regard to number of patients treated nor with number of patients achieving recommended goals. To address this issue in the Nordic countries, we evaluated the published literature...... are inadequately treated and have not achieved recommended treatment goals of total cholesterol ... disease, age, and gender. CONCLUSIONS: There is a considerable need to improve standards of preventive cardiology. Statins have to be given evidence based to achieve treatment goals according to lipid levels, and higher doses of statins or combination therapy with a statin and a cholesterol absorption...

  9. Improved characterization of EV preparations based on protein to lipid ratio and lipid properties.

    Directory of Open Access Journals (Sweden)

    Xabier Osteikoetxea

    Full Text Available In recent years the study of extracellular vesicles has gathered much scientific and clinical interest. As the field is expanding, it is becoming clear that better methods for characterization and quantification of extracellular vesicles as well as better standards to compare studies are warranted. The goal of the present work was to find improved parameters to characterize extracellular vesicle preparations. Here we introduce a simple 96 well plate-based total lipid assay for determination of lipid content and protein to lipid ratios of extracellular vesicle preparations from various myeloid and lymphoid cell lines as well as blood plasma. These preparations included apoptotic bodies, microvesicles/microparticles, and exosomes isolated by size-based fractionation. We also investigated lipid bilayer order of extracellular vesicle subpopulations using Di-4-ANEPPDHQ lipid probe, and lipid composition using affinity reagents to clustered cholesterol (monoclonal anti-cholesterol antibody and ganglioside GM1 (cholera toxin subunit B. We have consistently found different protein to lipid ratios characteristic for the investigated extracellular vesicle subpopulations which were substantially altered in the case of vesicular damage or protein contamination. Spectral ratiometric imaging and flow cytometric analysis also revealed marked differences between the various vesicle populations in their lipid order and their clustered membrane cholesterol and GM1 content. Our study introduces for the first time a simple and readily available lipid assay to complement the widely used protein assays in order to better characterize extracellular vesicle preparations. Besides differentiating extracellular vesicle subpopulations, the novel parameters introduced in this work (protein to lipid ratio, lipid bilayer order, and lipid composition, may prove useful for quality control of extracellular vesicle related basic and clinical studies.

  10. The association between HIV (treatment), pregnancy serum lipid concentrations and pregnancy outcomes: a systematic review.

    Science.gov (United States)

    Harmsen, Marissa J; Browne, Joyce L; Venter, Francois; Klipstein-Grobusch, Kerstin; Rijken, Marcus J

    2017-07-11

    Observed adverse effects of antiretroviral therapy (ART) on the lipid profile could be of significance in pregnancy. This systematic review aims to summarize studies that investigated the association between HIV, ART and serum lipids during pregnancy and adverse pregnancy outcomes. A systematic search was conducted in five electronic databases to obtain articles that measured serum lipid concentrations or the incidence of dyslipidaemia in HIV-infected pregnant women. Included articles were assessed for quality according to the Cochrane Risk of Bias Tool. The extracted data was analysed through descriptive analysis. Of the 1264 articles screened, 17 articles were included in this review; eleven reported the incidence of dyslipidaemia, and twelve on maternal serum lipid concentrations under the influence of HIV-infection and ART. No articles reported pregnancy outcomes in relation to serum lipids. Articles were of acceptable quality, but heterogenic in methods and study design. Lipid levels in HIV-infected women increased 1.5-3 fold over the trimesters of pregnancy, and remained within the physiological reference range. The percentage of women with dyslipidaemia was variable between the studies [0-88.9%] and highest in the groups on first generation protease inhibitors and for women on ART at conception. This systematic review observed physiologic concentrations of serum lipids for HIV-infected women receiving ART during pregnancy. Serum lipids were increased in users of first generation protease inhibitors and for those on treatment at conception. There was no information available about pregnancy outcomes. Future studies are needed which include HIV-uninfected control groups, control for potential confounders, and overcome limitations associated with included studies.

  11. Cell-based lipid flippase assay employing fluorescent lipid derivatives

    DEFF Research Database (Denmark)

    Jensen, Maria Stumph; Costa, Sara; Günther-Pomorski, Thomas

    2016-01-01

    P-type ATPases in the P4 subfamily (P4-ATPases) are transmembrane proteins unique for eukaryotes that act as lipid flippases, i.e., to translocate phospholipids from the exofacial to the cytofacial monolayer of cellular membranes. While initially characterized as aminophospholipid translocases, s...... flippase activities in the plasma membrane of cells, using yeast as an example.......P-type ATPases in the P4 subfamily (P4-ATPases) are transmembrane proteins unique for eukaryotes that act as lipid flippases, i.e., to translocate phospholipids from the exofacial to the cytofacial monolayer of cellular membranes. While initially characterized as aminophospholipid translocases......, studies of individual P4-ATPase family members from fungi, plants, and animals show that P4-ATPases differ in their substrate specificities and mediate transport of a broader range of lipid substrates. Here, we describe an assay based on fluorescent lipid derivatives to monitor and characterize lipid...

  12. Chemical and structural investigation of lipid nanoparticles: drug-lipid interaction and molecular distribution

    Science.gov (United States)

    Anantachaisilp, Suranan; Meejoo Smith, Siwaporn; Treetong, Alongkot; Pratontep, Sirapat; Puttipipatkhachorn, Satit; Rungsardthong Ruktanonchai, Uracha

    2010-03-01

    Lipid nanoparticles are a promising alternative to existing carriers in chemical or drug delivery systems. A key challenge is to determine how chemicals are incorporated and distributed inside nanoparticles, which assists in controlling chemical retention and release characteristics. This study reports the chemical and structural investigation of γ-oryzanol loading inside a model lipid nanoparticle drug delivery system composed of cetyl palmitate as solid lipid and Miglyol 812® as liquid lipid. The lipid nanoparticles were prepared by high pressure homogenization at varying liquid lipid content, in comparison with the γ-oryzanol free systems. The size of the lipid nanoparticles, as measured by the photon correlation spectroscopy, was found to decrease with increased liquid lipid content from 200 to 160 nm. High-resolution proton nuclear magnetic resonance (1H-NMR) measurements of the medium chain triglyceride of the liquid lipid has confirmed successful incorporation of the liquid lipid in the lipid nanoparticles. Differential scanning calorimetric and powder x-ray diffraction measurements provide complementary results to the 1H-NMR, whereby the crystallinity of the lipid nanoparticles diminishes with an increase in the liquid lipid content. For the distribution of γ-oryzanol inside the lipid nanoparticles, the 1H-NMR revealed that the chemical shifts of the liquid lipid in γ-oryzanol loaded systems were found at rather higher field than those in γ-oryzanol free systems, suggesting incorporation of γ-oryzanol in the liquid lipid. In addition, the phase-separated structure was observed by atomic force microscopy for lipid nanoparticles with 0% liquid lipid, but not for lipid nanoparticles with 5 and 10% liquid lipid. Raman spectroscopic and mapping measurements further revealed preferential incorporation of γ-oryzanol in the liquid part rather than the solid part of in the lipid nanoparticles. Simple models representing the distribution of γ-oryzanol and

  13. Chemical and structural investigation of lipid nanoparticles: drug-lipid interaction and molecular distribution

    International Nuclear Information System (INIS)

    Anantachaisilp, Suranan; Smith, Siwaporn Meejoo; Treetong, Alongkot; Ruktanonchai, Uracha Rungsardthong; Pratontep, Sirapat; Puttipipatkhachorn, Satit

    2010-01-01

    Lipid nanoparticles are a promising alternative to existing carriers in chemical or drug delivery systems. A key challenge is to determine how chemicals are incorporated and distributed inside nanoparticles, which assists in controlling chemical retention and release characteristics. This study reports the chemical and structural investigation of γ-oryzanol loading inside a model lipid nanoparticle drug delivery system composed of cetyl palmitate as solid lipid and Miglyol 812 as liquid lipid. The lipid nanoparticles were prepared by high pressure homogenization at varying liquid lipid content, in comparison with the γ-oryzanol free systems. The size of the lipid nanoparticles, as measured by the photon correlation spectroscopy, was found to decrease with increased liquid lipid content from 200 to 160 nm. High-resolution proton nuclear magnetic resonance ( 1 H-NMR) measurements of the medium chain triglyceride of the liquid lipid has confirmed successful incorporation of the liquid lipid in the lipid nanoparticles. Differential scanning calorimetric and powder x-ray diffraction measurements provide complementary results to the 1 H-NMR, whereby the crystallinity of the lipid nanoparticles diminishes with an increase in the liquid lipid content. For the distribution of γ-oryzanol inside the lipid nanoparticles, the 1 H-NMR revealed that the chemical shifts of the liquid lipid in γ-oryzanol loaded systems were found at rather higher field than those in γ-oryzanol free systems, suggesting incorporation of γ-oryzanol in the liquid lipid. In addition, the phase-separated structure was observed by atomic force microscopy for lipid nanoparticles with 0% liquid lipid, but not for lipid nanoparticles with 5 and 10% liquid lipid. Raman spectroscopic and mapping measurements further revealed preferential incorporation of γ-oryzanol in the liquid part rather than the solid part of in the lipid nanoparticles. Simple models representing the distribution of γ-oryzanol and

  14. Neutron reflectivity studies of single lipid bilayers supported on planar substrates

    Energy Technology Data Exchange (ETDEWEB)

    Krueger, S.; Orts, W.J.; Berk, N.F.; Majkrzak, C.F. [National Inst. of Standards and Technology, Gaithersburg, MD (United States); Koenig, B.W. [National Inst. of Health, Bethesda, MD (United States)

    1994-12-31

    Neutron reflectivity was used to probe the structure of single phosphatidylcholine (PC) lipid bilayers adsorbed onto a planar silicon surface in an aqueous environment. Fluctuations in the neutron scattering length density profiles perpendicular to the silicon/water interface were determined for different lipids as a function of the hydrocarbon chain length. The lipids were studied in both the gel and liquid crystalline phases by monitoring changes in the specularly-reflected neutron intensity as a function of temperature. Contrast variation of the neutron scattering length density was applied to both the lipid and the solvent. Scattering length density profiles were determined using both model-independent and model-dependent fitting methods. During the reflectivity measurements, a novel experimental set-up was implemented to decrease the incoherent background scattering due to the solvent. Thus, the reflectivity was measured to Q {approx} 0.3{Angstrom}{sup -1}, covering up to seven orders of magnitude in reflected intensity, for PC bilayers in D{sub 2}O and silicon-matched (38% D{sub 2}O/62% H{sub 2}O) water. The kinetics of lipid adsorption at the silicon/water interface were also explored by observing changes in the reflectivity at low Q values under silicon-matched water conditions.

  15. Neutron scattering to study membrane systems: from lipid vesicles to living cells.

    Energy Technology Data Exchange (ETDEWEB)

    Nickels, Jonathan D. [ORNL; Chatterjee, Sneha [ORNL; Stanley, Christopher B. [ORNL; Qian, Shuo [ORNL; Cheng, Xiaolin [ORNL; Myles, Dean A A [ORNL; Standaert, Robert F. [ORNL; Elkins, James G. [ORNL; Katsaras, John [ORNL

    2017-03-01

    The existence and role of lateral lipid organization in biological membranes has been studied and contested for more than 30 years. Lipid domains, or rafts, are hypothesized as scalable compartments in biological membranes, providing appropriate physical environments to their resident membrane proteins. This implies that lateral lipid organization is associated with a range of biological functions, such as protein co-localization, membrane trafficking, and cell signaling, to name just a few. Neutron scattering techniques have proven to be an excellent tool to investigate these structural features in model lipids, and more recently, in living cells. I will discuss our recent work using neutrons to probe the structure and mechanical properties in model lipid systems and our current efforts in using neutrons to probe the structure and organization of the bilayer in a living cell. These efforts in living cells have used genetic and biochemical strategies to generate a large neutron scattering contrast, making the membrane visible. I will present our results showing in vivo bilayer structure and discuss the outlook for this approach.

  16. Dietary phytochemical index and subsequent changes of lipid profile: A 3-year follow-up in Tehran Lipid and Glucose Study in Iran

    Directory of Open Access Journals (Sweden)

    Mahdieh Golzarand

    2014-07-01

    Full Text Available BACKGROUND: High intakes of phytochemical-rich foods have beneficial effects on lipid profiles and cardiovascular disease (CVD. In this study, we assessed the association between the dietary phytochemical index (PI and changes in lipid profile after 3-year follow-up among Iranian adults. METHODS: This longitudinal study was conducted in 1983 subjects, aged 19-70 years, selected among participants of the Tehran Lipid and Glucose Study. Dietary data were collected by using a validated semi-quantitative food frequency questionnaire with 168 food items at baseline. PI was calculated based on daily energy derived from [(phytochemical-rich foods kcal/total daily energy intake kcal × 100]. Lipid profile was measured at baseline and after 3 years and changes in serum lipid profiles were assessed during 3-year follow-up. RESULTS: The mean age of participants was 40.4 ± 13.0 years; participants in the highest PI quartile category were more likely to be older. After 3 years of follow-up, total cholesterol was significantly lower in the highest quartile compared with lower quartile of PI in men (181 ± 3 vs. 189 ± 3, P for trend <0.05. There were significant inverse association between dietary PI and 3 years changes of total cholesterol [β: −5.6, 95% confidence interval (CI = −9.3, −1.8], triglycerides (β = −13.7, 95% CI = −24.6, −2.8, and non-high-density lipoprotein cholesterol (HDL-C (β = −6.2, 95% CI = −10.8, −1.5, in highest quartile of PI in men. Lipid profiles showed no significant changes over the study period in women. CONCLUSION: Higher dietary PI is associated with 3 years improvement of total cholesterol, triglycerides, and non-HDL-C. Higher consumption of phytochemical-rich foods is recommended to prevent CVD.   Keywords: Phytochemical, Triglyceride, Cholesterol, Fruit and vegetables, Whole Grains 

  17. Common and Rare Variant Association Study for Plasma Lipids and Coronary Artery Disease.

    Science.gov (United States)

    Tada, Hayato; Kawashiri, Masa-aki; Konno, Tetsuo; Yamagishi, Masakazu; Hayashi, Kenshi

    2016-01-01

    Blood lipid levels are highly heritable and modifiable risk factors for coronary artery disease (CAD), and are the leading cause of death worldwide. These facts have motivated human genetic association studies that have the substantial potential to define the risk factors that are causal and to identify pathways and therapeutic targets for lipids and CAD.The success of the HapMap project that provided an extensive catalog of human genetic variations and the development of microarray based genotyping chips (typically containing variations with allele frequencies > 5%) facilitated common variant association study (CVAS; formerly termed genome-wide association study, GWAS) identifying disease-associated variants in a genome-wide manner. To date, 157 loci associated with blood lipids and 46 loci with CAD have been successfully identified, accounting for approximately 12%-14% of heritability for lipids and 10% of heritability for CAD. However, there is yet a major challenge termed "missing heritability problem," namely the observation that loci detected by CVAS explain only a small fraction of the inferred genetic variations. To explain such missing portions, focuses in genetic association studies have shifted from common to rare variants. However, it is challenging to apply rare variant association study (RVAS) in an unbiased manner because such variants typically lack the sufficient number to be identified statistically.In this review, we provide a current understanding of the genetic architecture mostly derived from CVAS, and several updates on the progress and limitations of RVAS for lipids and CAD.

  18. Physical Properties for Lipids Based Process and Product Design

    DEFF Research Database (Denmark)

    Ana Perederic, Olivia; Kalakul, Sawitree; Sarup, Bent

    Lipid processing covers several oil and fats technologies such as: edible oil production, biodieselproduction, oleochemicals (e.g.: food additives, detergents) and pharmaceutical product manufacturing. New demands regarding design and development of better products and more sustainable processes...... related to lipids technology, emerge according to consumers demanding improved product manufacturing from sustainable resources and new legislation regarding environmental safety [1]. Physical and thermodynamic property data and models for prediction of pure compound properties and mixtures properties...... involving lipids represent the basic and most important requirements for process product design, simulation and optimization. Experimentally measured values of involved compounds are desirable, but in most of the cases these are not available for all the compounds and properties needed. The lack...

  19. A model of lipid rearrangements during pore formation in the DPPC lipid bilayer.

    Science.gov (United States)

    Wrona, Artur; Kubica, Krystian

    2017-07-10

    The molecular bases of pore formation in the lipid bilayer remain unclear, as do the exact characteristics of their sizes and distributions. To understand this process, numerous studies have been performed on model lipid membranes including cell-sized giant unilamellar vesicles (GUV). The effect of an electric field on DPPC GUV depends on the lipid membrane state: in the liquid crystalline phase the created pores have a cylinder-like shape, whereas in the gel phase a crack has been observed. The aim of the study was to investigate the geometry of pores created in a lipid bilayer in gel and liquid crystalline phases in reference to literature experimental data. A mathematical model of the pore in a DPPC lipid bilayer developed based on the law of conservation of mass and the assumption of constant volume of lipid molecules, independent of their conformation, allows for analysis of pore shape and accompanying molecular rearrangements. The membrane area occupied by the pore of a cylinder-like shape is greater than the membrane area occupied by lipid molecules creating the pore structure (before pore appearance). Creation of such pores requires more space, which can be achieved by conformational changes of lipid chains toward a more compact state. This process is impossible for a membrane in the most compact, gel phase. We show that the geometry of the pores formed in the lipid bilayer in the gel phase must be different from the cylinder shape formed in the lipid bilayer in a liquid crystalline state, confirming experimental studies. Furthermore, we characterize the occurrence of the 'buffer' zone surrounding pores in the liquid crystalline phase as a mechanism of separation of neighbouring pores.

  20. Chemical and structural investigation of lipid nanoparticles: drug-lipid interaction and molecular distribution

    Energy Technology Data Exchange (ETDEWEB)

    Anantachaisilp, Suranan; Smith, Siwaporn Meejoo [Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400 (Thailand); Treetong, Alongkot; Ruktanonchai, Uracha Rungsardthong [National Nanotechnology Center, National Science and Technology Development Agency, 111 Thailand Science Park, Paholyothin Road, Klong 1, Klong Luang, Pathumthani 12120 (Thailand); Pratontep, Sirapat [College of KMITL Nanotechnology, King Mongkut' s Institute of Technology Ladkrabang, Bangkok (Thailand); Puttipipatkhachorn, Satit, E-mail: uracha@nanotec.or.th [Department of Manufacturing Pharmacy, Faculty of Pharmacy, Mahidol University, Bangkok 10400 (Thailand)

    2010-03-26

    Lipid nanoparticles are a promising alternative to existing carriers in chemical or drug delivery systems. A key challenge is to determine how chemicals are incorporated and distributed inside nanoparticles, which assists in controlling chemical retention and release characteristics. This study reports the chemical and structural investigation of {gamma}-oryzanol loading inside a model lipid nanoparticle drug delivery system composed of cetyl palmitate as solid lipid and Miglyol 812 as liquid lipid. The lipid nanoparticles were prepared by high pressure homogenization at varying liquid lipid content, in comparison with the {gamma}-oryzanol free systems. The size of the lipid nanoparticles, as measured by the photon correlation spectroscopy, was found to decrease with increased liquid lipid content from 200 to 160 nm. High-resolution proton nuclear magnetic resonance ({sup 1}H-NMR) measurements of the medium chain triglyceride of the liquid lipid has confirmed successful incorporation of the liquid lipid in the lipid nanoparticles. Differential scanning calorimetric and powder x-ray diffraction measurements provide complementary results to the {sup 1}H-NMR, whereby the crystallinity of the lipid nanoparticles diminishes with an increase in the liquid lipid content. For the distribution of {gamma}-oryzanol inside the lipid nanoparticles, the {sup 1}H-NMR revealed that the chemical shifts of the liquid lipid in {gamma}-oryzanol loaded systems were found at rather higher field than those in {gamma}-oryzanol free systems, suggesting incorporation of {gamma}-oryzanol in the liquid lipid. In addition, the phase-separated structure was observed by atomic force microscopy for lipid nanoparticles with 0% liquid lipid, but not for lipid nanoparticles with 5 and 10% liquid lipid. Raman spectroscopic and mapping measurements further revealed preferential incorporation of {gamma}-oryzanol in the liquid part rather than the solid part of in the lipid nanoparticles. Simple models

  1. Comparative studies of the lipid characteristics and industrial ...

    African Journals Online (AJOL)

    Characterization of oil from African walnut seed and Indian almond seeds was studied by analysing the lipid extracted from the seeds for their saponification value, iodine value, free fatty acid and acid value. The result of the analysis shows that the saponification value, free fatty acid value, acid value and iodine value of ...

  2. A comparative study of soft sensor design for lipid estimation of microalgal photobioreactor system with experimental validation.

    Science.gov (United States)

    Yoo, Sung Jin; Jung, Dong Hwi; Kim, Jung Hun; Lee, Jong Min

    2015-03-01

    This study examines the applicability of various nonlinear estimators for online estimation of the lipid concentration in microalgae cultivation system. Lipid is a useful bio-product that has many applications including biofuels and bioactives. However, the improvement of lipid productivity using real-time monitoring and control with experimental validation is limited because measurement of lipid in microalgae is a difficult and time-consuming task. In this study, estimation of lipid concentration from other measurable sources such as biomass or glucose sensor was studied. Extended Kalman filter (EKF), unscented Kalman filter (UKF), and particle filter (PF) were compared in various cases for their applicability to photobioreactor systems. Furthermore, simulation studies to identify appropriate types of sensors for estimating lipid were also performed. Based on the case studies, the most effective case was validated with experimental data and found that UKF and PF with time-varying system noise covariance is effective for microalgal photobioreactor system. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Lxr-driven enterocyte lipid droplet formation delays transport of ingested lipids.

    Science.gov (United States)

    Cruz-Garcia, Lourdes; Schlegel, Amnon

    2014-09-01

    Liver X receptors (Lxrs) are master regulators of cholesterol catabolism, driving the elimination of cholesterol from the periphery to the lumen of the intestine. Development of pharmacological agents to activate Lxrs has been hindered by synthetic Lxr agonists' induction of hepatic lipogenesis and hypertriglyceridemia. Elucidating the function of Lxrs in regulating enterocyte lipid handling might identify novel aspects of lipid metabolism that are pharmacologically amenable. We took a genetic approach centered on the single Lxr gene nr1h3 in zebrafish to study the role of Lxr in enterocyte lipid metabolism. Loss of nr1h3 function causes anticipated gene regulatory changes and cholesterol intolerance, collectively reflecting high evolutionary conservation of zebrafish Lxra function. Intestinal nr1h3 activation delays transport of absorbed neutral lipids, with accumulation of neutral lipids in enterocyte cytoplasmic droplets. This delay in transport of ingested neutral lipids protects animals from hypercholesterolemia and hepatic steatosis induced by a high-fat diet. On a gene regulatory level, Lxra induces expression of acsl3a, which encodes acyl-CoA synthetase long-chain family member 3a, a lipid droplet-anchored protein that directs fatty acyl chains into lipids. Forced overexpression of acls3a in enterocytes delays, in part, the appearance of neutral lipids in the vasculature of zebrafish larvae. Activation of Lxr in the intestine cell-autonomously regulates the rate of delivery of absorbed lipids by inducting a temporary lipid intestinal droplet storage depot. Copyright © 2014 by the American Society for Biochemistry and Molecular Biology, Inc.

  4. Clinical studies with oral lipid based formulations of poorly soluble compounds

    DEFF Research Database (Denmark)

    Fatouros, Dimitrios; Karpf, Ditte M; Nielsen, Flemming S

    2007-01-01

    . Several drug products intended for oral administration have been marketed utilizing lipid and surfactant based formulations. Sandimmune((R)) and Sandimmune Neoral((R)) (cyclosporin A, Novartis), Norvir((R)) (ritonavir), and Fortovase((R)) (saquinavir) have been formulated in self-emulsifying drug delivery...... systems (SEDDS). This review summarizes published pharmacokinetic studies of orally administered lipid based formulations of poorly aqueous soluble drugs in human subjects. Special attention has been paid to the physicochemical characteristics of the formulations, when available and the impact...

  5. Characterization of interactions of eggPC lipid structures with different biomolecules.

    Science.gov (United States)

    Corrales Chahar, F; Díaz, S B; Ben Altabef, A; Gervasi, C; Alvarez, P E

    2018-01-01

    In this paper we study the interactions of two biomolecules (ascorbic acid and Annonacin) with a bilayer lipid membrane. Egg yolk phosphatidylcholine (eggPC) liposomes (in crystalline liquid state) were prepared in solutions of ascorbic acid (AA) at different concentration levels. On the other hand, liposomes were doped with Annonacin (Ann), a mono-tetrahydrofuran acetogenin (ACG), which is an effective citotoxic substance. While AA pharmacologic effect and action mechanisms are widely known, those of Ann's are only very recently being studied. Both Fourier Transformed Infrared (FTIR) and Raman spectroscopic techniques were used to study the participation of the main functional groups of the lipid bilayer involved in the membrane-solution interaction. The obtained spectra were comparatively analyzed, studying the spectral bands corresponding to both the hydrophobic and the hydrophilic regions in the lipid bilayer. Electrochemical experiments namely; impedance spectroscopy (EIS) and cyclic voltamperometry (CV) were used as the main characterization techniques to analyse stability and structural changes of a model system of supported EggPC bilayer in connection with its interactions with AA and Ann. At high molar ratios of AA, there is dehydration in both populations of the carbonyl group of the polar head of the lipid. On the other hand, Ann promotes the formation of hydrogen bonds with the carbonyl groups. No interaction between AA and phosphate groups is observed at low and intermediate molar ratios. Ann is expected to be able to induce the dehydration of the phosphate groups without the subsequent formation of H bonds with them. According to the electrochemical analysis, the interaction of AA with the supported lipid membrane does not alter its dielectric properties. This fact can be related to the conservation of structured water of the phosphate groups in the polar heads of the lipid. On the other hand, the incorporation of Ann into the lipid membrane generates

  6. Association of lipids and antropometrics measures of adiposity in adolescents

    OpenAIRE

    Paulo César Barauce Bento; Maria de Fátima Aguiar Lopes; Suelen Meira Góes; Gerusa Eisfeld Milano; Fabrício Cieslak; Neiva Leite; Rosana Bento Radominski

    2009-01-01

    The arm of this study was to relate lipidic levels to global and central obesity in adolescents. Transversal, descriptive and co-relational study. 127 pubescent subjects took part in this study, 71 girls (13.39+1.81 years) and 56 boys (13.10+1.97 years). It was identified global adiposity through the body mass index (BMI) as well central adiposity through the waist circumference (WC), according to age, sex, and ethnics. It had been determined levels of total cholesterol (TC), high density lip...

  7. SAXS Study of Sterically Stabilized Lipid Nanocarriers Functionalized by DNA

    Science.gov (United States)

    Angelov, Borislav; Angelova, Angelina; Filippov, Sergey; Karlsson, Göran; Terrill, Nick; Lesieur, Sylviane; Štěpánek, Petr

    2012-03-01

    The structure of novel spontaneously self-assembled plasmid DNA/lipid complexes is investigated by means of synchrotron radiation small-angle X-ray scattering (SAXS) and Cryo-TEM imaging. Liquid crystalline (LC) hydrated lipid systems are prepared using the non-ionic lipids monoolein and DOPE-PEG2000 and the cationic amphiphile CTAB. The employed plasmid DNA (pDNA) is encoding for the human protein brain-derived neurotrophic factor (BDNF). A coexistence of nanoparticulate objects with different LC inner organizations is established. A transition from bicontinuous membrane sponges, cubosome intermediates and unilamelar liposomes to multilamellar vesicles, functionalized by pDNA, is favoured upon binding and compaction of pBDNF onto the cationic PEGylated lipid nanocarriers. The obtained sterically stabilized multicompartment nanoobjects, with confined supercoiled plasmid DNA (pBDNF), are important in the context of multicompartment lipid nanocarriers of interest for gene therapy of neurodegenerative diseases.

  8. SAXS Study of Sterically Stabilized Lipid Nanocarriers Functionalized by DNA

    International Nuclear Information System (INIS)

    Angelov, Borislav; Filippov, Sergey; Štepánek, Petr; Angelova, Angelina; Lesieur, Sylviane; Karlsson, Göran; Terrill, Nick

    2012-01-01

    The structure of novel spontaneously self-assembled plasmid DNA/lipid complexes is investigated by means of synchrotron radiation small-angle X-ray scattering (SAXS) and Cryo-TEM imaging. Liquid crystalline (LC) hydrated lipid systems are prepared using the non-ionic lipids monoolein and DOPE-PEG 2000 and the cationic amphiphile CTAB. The employed plasmid DNA (pDNA) is encoding for the human protein brain-derived neurotrophic factor (BDNF). A coexistence of nanoparticulate objects with different LC inner organizations is established. A transition from bicontinuous membrane sponges, cubosome intermediates and unilamelar liposomes to multilamellar vesicles, functionalized by pDNA, is favoured upon binding and compaction of pBDNF onto the cationic PEGylated lipid nanocarriers. The obtained sterically stabilized multicompartment nanoobjects, with confined supercoiled plasmid DNA (pBDNF), are important in the context of multicompartment lipid nanocarriers of interest for gene therapy of neurodegenerative diseases.

  9. New aspects of phloem-mediated long-distance lipid signaling in plants

    Directory of Open Access Journals (Sweden)

    Urs Florian Benning

    2012-03-01

    Full Text Available Plants are sessile and cannot move to appropriate hiding places or feeding grounds to escape adverse conditions. As a consequence, they evolved mechanisms to detect changes in their environment, communicate these to different organs, and adjust development accordingly. These adaptations include two long-distance transport systems which are essential in plants: the xylem and the phloem. The phloem serves as a major trafficking pathway for assimilates, viruses, RNA, plant hormones, metabolites, and proteins with functions ranging from synthesis to metabolism to signaling. The study of signaling compounds within the phloem is essential for our understanding of plant communication of environmental cues. Determining the nature of signals and the mechanisms by which they are communicated through the phloem will lead to a more complete understanding of plant development and plant responses to stress. In our analysis of Arabidopsis phloem exudates, we had identified several lipid-binding proteins as well as fatty acids and lipids. The latter are not typically expected in the aqueous environment of sieve elements. Hence, lipid transport in the phloem has been given little attention until now. Long-distance transport of hydrophobic compounds in an aqueous system is not without precedence in biological systems: a variety of lipids is found in human blood and are often bound to proteins. Some lipid-protein complexes are transported to other tissues for storage, use, modification, or degradation, others serve as messengers and modulate transcription factor activity. By simple analogy it raises the possibility that lipids and the respective lipid-binding proteins in the phloem serve similar functions in plants and play an important role in stress and developmental signaling. Here, we introduce the lipid-binding proteins and the lipids we found in the phloem and discuss the possibility that they may play an important role in developmental and stress signaling.

  10. Omic studies reveal the pathogenic lipid droplet proteins in non-alcoholic fatty liver disease

    Directory of Open Access Journals (Sweden)

    Xuelin Zhang

    2016-10-01

    Full Text Available Abstract Non-alcoholic fatty liver disease (NAFLD is an epidemic metabolic condition driven by an underlying lipid homeostasis disorder. The lipid droplet (LD, the main organelle involved in neutral lipid storage and hydrolysis, is a potential target for NAFLD therapeutic treatment. In this review, we summarize recent progress elucidating the connections between LD-associated proteins and NAFLD found by genome-wide association studies (GWAS, genomic and proteomic studies. Finally, we discuss a possible mechanism by which the protein 17β-hydroxysteroid dehydrogenase 13 (17β-HSD13 may promote the development of NAFLD.

  11. Betatrophin provides a new insight into diabetes treatment and lipid metabolism (Review)

    OpenAIRE

    ZHU, JIN-ZHOU; YU, CHAO-HUI; LI, YOU-MING

    2014-01-01

    Replenishing the insulin-producing β-cell mass is considered to be a potential cure for diabetes. A recent study identified a secreted protein, known as betatrophin, which potently induces pancreatic β-cell proliferation. Notably, a number of studies reportedly identified betatrophin, which is also known as lipasin, atypical angiopoietin-like 8 and refeeding-induced fat and liver protein, and considered to be a novel regulator in lipid metabolism according to the studies. The identification o...

  12. Optimization of lipids production by Cryptococcus laurentii 11 using cheese whey with molasses

    Directory of Open Access Journals (Sweden)

    Rodrigo Fernandes Castanha

    2014-06-01

    Full Text Available This study aimed the optimization of culture condition and composition for production of Cryptococcus laurentii 11 biomass and lipids in cheese whey medium supplemented with sugarcane molasses. The optimization of pH, fermentation time, and molasses concentration according to a full factorial statistical experimental design was followed by a Plackett-Burman experimental design, which was used to determine whether the supplementation of the culture medium by yeast extract and inorganic salts could provide a further enhancement of lipids production. The following conditions and composition of the culture medium were found to optimize biomass and lipids production: 360 h fermentation, 6.5 pH and supplementation of (g L-1: 50 molasses, 0.5 yeast extract, 4 KH2PO4, 1 Na2HPO4, 0.75 MgSO4•7H2O and 0.002 ZnSO4•H2O. Additional supplementation with inorganic salts and yeast extract was essential to optimize the production, in terms of product concentration and productivity, of neutral lipids by C. laurentii 11. Under this optimized condition, the production of total lipids increased by 133% in relation to control experiment (from 1.27 to 2.96 g L-1. The total lipids indicated a predominant (86% presence of neutral lipids with high content of 16- and 18- carbon-chain saturated and monosaturated fatty acids. This class of lipids is considered especially suitable for the production of biodiesel.

  13. Seasonal changes in hepatocytic lipid droplets, glycogen deposits, and rough endoplasmic reticulum along the natural breeding cycle of female ohrid trout (Salmo letnica Kar.)-A semiquantitative ultrastructural study.

    Science.gov (United States)

    Jordanova, Maja; Rebok, Katerina; Malhão, Fernanda; Rocha, Maria J; Rocha, Eduardo

    2016-08-01

    This study on wild female Ohrid trout was primarily designed to provide a general overview of the breeding cycle influence upon selected aspects of hepatocytes. According with a semiquantitatively evaluation, some of these cell's structural compartments change during the breeding cycle. Structural modifications were disclosed in the relative occurrence of lipid, glycogen, and RER content during breeding cycle. The relative amount of lipid deposits in the hepatocytes was much greater in previtellogenesis, and decreased postspawning. So, while the seasonal changes in RER were positively related with the ovary maturation status, those of the lipid droplets followed an opposite trend. The hepatocytic glycogen occurred rarely, mainly in late-vitellogenesis and spawning, suggesting that in this species such kind of energy storage is comparatively unimportant. Lipid accumulation and later usage is, probably, the relevant biochemical pathway for Ohrid trout in the wild. While glycogen and RER contents were positively correlated with the gonadosomatic index, lipids were negatively correlated. Additionally, glycogen inclusions were positively correlated with the plasma estradiol levels. When comparing seasonal patterns from wild Ohrid trout with those from well-studied rainbow and brown trout (specimens studied were from aquaculture), there are contradicting results as to lipid and glycogen reserves, and also as to RER loads. The differences among the mentioned trout can result from intrinsic interspecies differences or may be associated with natural feeding conditions versus feeding with commercially prepared diets, or other factors. This study offers new data useful as standard to access liver pathology in wild and aquacultured Ohrid trout. Microsc. Res. Tech. 79:700-706, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  14. Prenatal hyperandrogenism and lipid profile during different age stages: an experimental study.

    Science.gov (United States)

    Heber, María F; Ferreira, Silvana R; Vélez, Leandro M; Motta, Alicia B

    2013-02-01

    The present study investigates the effect of prenatal hyperandrogenization on lipid metabolism and oxidant/antioxidant balance. Experimental study. Research institute. Pregnant Sprague Dawley rats were subcutaneously injected with 2 mg free T between days 16 and 19 of pregnancy, and controls (C) received vehicle (0.1 mL of sesame oil). Prenatally hyperandrogenized female offspring (T2) had a condition that resembles polycystic ovary (PCO). Animals were weighed and killed at 21 and 60 days of age (N = 15 rats/group). Ovarian tissue and truncal blood were obtained from the C and T2 groups. Circulating lipid profile (total cholesterol, high-density lipoprotein [HDL], low-density lipoprotein [LDL] cholesterol, and triglycerides) was quantified by colorimetric-enzymatic methods. Ovarian oxidative stress was evaluated by quantifying lipid peroxidation and glutathione content by spectofotometric assays. Ovarian fat content was evaluated by Red Oil staining and ovarian messenger RNA (mRNA) expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) by real-time polymerase chain reaction (PCR). At 60 days of age, 100% of group C rats and 20% of group T2 rats ovulated. At 21 days of age the T2 rats displayed lower body weight than C rats; however, at 60 days of age T2 and C rats showed similar body weights. The lipid profile (total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides) was altered in the anovulatory and ovulatory phenotype of the T2 group, but the levels were higher in the anovulatory phenotype. Lipid peroxidation of rats at 21 and 60 days of age from T2 was similar to C but the antioxidant glutathione level was decreased in 21-day-old rats compared with C rats. The lipid content of ovarian tissue, determined by Red Oil staining, was higher in the T2 than in the C group. The mRNA expression of ovarian PPAR-γ, quantified by real time PCR, decreased in anovulatory rats at 60 days of age from T2 compared to C rats. Our findings reveal

  15. Adiposity indicators lipid accumulation product and triglyceride-glucose index as alternate criteria for the diagnosis of metabolic obesity in adult

    OpenAIRE

    Mariya Tabassum; Md. Matiur Rahman; Miliva Mozaffor

    2018-01-01

    Metabolic obesity refers to the state of having metabolic syndrome irrespective of one’s BMI. This study was aimed to elucidate the lipid accumulation product and triglyceride-glucose index as simple and alternate criteria for the detecting metabolic obesity in adult. The study was conducted in 200 adult (age range: 19-45 years). According to lipid accumulation product and Triglyceride-glucose index, the prevalence of metabolic obesity was 54.0% and 53.5% respectively. With a cutoff value of ...

  16. Evaluation of radiolabeled curcumin-loaded solid lipid nanoparticles usage as an imaging agent in liver-spleen scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Ayan, Arif Kursad [Department of Nuclear Medicine, Ataturk University, 25240 Erzurum (Turkey); Yenilmez, Ayse, E-mail: yenilmez2014@gmail.com [Department of Nanoscience and Nanoengineering, Ataturk University, 25240 Erzurum (Turkey); Department of Molecular Biology and Genetics, Erzurum Technical University, 25240 Erzurum (Turkey); Eroglu, Hayrettin [Department of Biomedical Engineering, Ataturk University, 25240 Erzurum (Turkey)

    2017-06-01

    Curcumin-loaded solid lipid nanoparticles (C-SLNs) were prepared using micro emulsion and ultrasonication methods in the first stage of this study to determine the role of C-SLN on liver-spleen scintigraphy. It was concluded that the curcumin that was encapsulated in solid lipid nanoparticles had a β′ polymorph structure according to the X-ray diffraction (XRD) analysis. İt was concluded that these particles were at nano scale according to the laser diffraction (LD) analysis. Fourier transform infrared spectroscopy (FT-IR) analysis suggested an interaction between the curcumin and the solid lipid matrix, and the curcumin was loaded on the solid lipid nanoparticles. Moreover, the particles were concluded to be spherical and at nanoscale according to the scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images. On the other hand, thermogravimetric analysis (TGA) suggested that the curcumin loaded solid nanoparticles were stable against the temperature. C-SLNs were labeled with Technetium-99 m ({sup 99m}Tc) radioisotope in the second stage of the study, then using scintigraphic methods in-vivo studies were performed on New Zealand rabbit and made a comparison with Phytate colloid, routinely used in liver-spleen scintigraphy. After analyzing the images and the biological distributions obtained from the experiments, uptake was observed in the liver and the spleen. Following from the experiment results, {sup 99m}Tc-labeled C-SLNs was concluded to be a possible imaging agent. In particular, it could be a new radiopharmaceutical alternative to {sup 99m}Tc-labeled compounds that are used in liver and spleen imaging in colloid scintigraphy. - Graphıcal abstract: Display Omitted - Hıghlıghts: • Curcumin-loaded solid lipid nanoparticles (C-SLNs) were prepared and examined characterization studies. • The C-SLNs were labeled with {sup 99m}Tc and made a comparison with Phytate colloid, routinely used in liver-spleen scintigraphy. • In vivo

  17. Consumption of seafood and its estimated heavy metals are associated with lipid profile and oxidative lipid damage on healthy adults from a Spanish Mediterranean area: A cross-sectional study.

    Science.gov (United States)

    Aranda, N; Valls, R M; Romeu, M; Sánchez-Martos, V; Albaladejo, R; Fernández-Castillejo, S; Nogués, R; Catalán, Ú; Pedret, A; Espinel, A; Delgado, M A; Arija, V; Sola, R; Giralt, M

    2017-07-01

    The association between the consumption of seafood and its benefits on cardiovascular (CVD) risk can be challenged by its heavy metal (HM) content. This study aimed to explore the association of seafood consumption and its estimated HM contents with the lipid profile and lipid oxidation biomarkers in adults from a Spanish Mediterranean area who do not present risk factors for CVD. In this cross-sectional study, the clinical history, three-day dietary record, lipid profile (LDLc, HDLc, APOB/A, and triglyceride levels), plasma oxidised LDL (oxLDL) and 8-isoprostane levels of 81 adults without risk factors for CVD [43% men, with a mean age of 43.6 years (95%CI: 40.1-47.1)] were assessed. The HM [arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb)] contents of seafood were estimated according to data from analyses of marine species in the same Mediterranean area. Moderate adherence to the Mediterranean diet (score: 4.6 of 9) with a mean seafood consumption of 74.9g/day (95%CI: 59.9-89.9), including 22.7g of shellfish per day (95%CI: 13.5-31.9), was observed. The estimated HM contents were lower than the provisional tolerable weekly intakes (PTWIs): 21.12µg/kg/week As, 0.57µg/kg/week InAs, 0.15µg/kg/week Cd, 1.11µg/kg/week Hg and 0.28µg/kg/week Pb. After adjusting by confounder variables, an increase in shellfish consumption was associated with increases in the levels of LDLc (P=0.013), non-HDLc (P=0.015), APOB/A (P=0.02) and plasma oxLDL (P=0.002). Moreover, an increase in the estimated As and Hg levels in shellfish was associated with an increase in LDLc (P=0.015 and P=0.018, respectively), non-HDLc (Pconsumption, even by a moderate amount, could favour a pro-atherogenic lipid profile and a higher level of oxidised LDL. These associations are likely influenced by the estimated exposure to As and Hg from shellfish despite these values are lower than the PTWIs. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Single-component solid lipid nanocarriers prepared with ultra-long chain amphiphilic lipids

    DEFF Research Database (Denmark)

    Wei, Wei; Lu, Xiaonan; Wang, Zegao

    2017-01-01

    HYPOTHESIS: Synthetic sugar alcohol mono-behenates with high melting points, surface activity and resistance to enzymatic lipolysis, are expected to form stable single-component solid lipid nanocarriers (SC-SLNs). The preparation methods and the polar head group of the molecules should affect the......-probe sonication method had a micelle structure with fenofibrate incorporated into a lipid monolayer. This study provides an insight into the systematic development of novel amphiphilic lipids for solid lipid-based drug delivery system.......HYPOTHESIS: Synthetic sugar alcohol mono-behenates with high melting points, surface activity and resistance to enzymatic lipolysis, are expected to form stable single-component solid lipid nanocarriers (SC-SLNs). The preparation methods and the polar head group of the molecules should affect...... using the lipolysis model. The structure and drug distribution of the nanocarriers were studied using AFM and TEM. FINDINGS: Both the polar head group of the molecules and the preparation methods affect the particle size and size distribution. Nanocarriers prepared with sorbitol mono-behenates showed...

  19. GPS-Lipid: a robust tool for the prediction of multiple lipid modification sites

    OpenAIRE

    Xie, Yubin; Zheng, Yueyuan; Li, Hongyu; Luo, Xiaotong; He, Zhihao; Cao, Shuo; Shi, Yi; Zhao, Qi; Xue, Yu; Zuo, Zhixiang; Ren, Jian

    2016-01-01

    As one of the most common post-translational modifications in eukaryotic cells, lipid modification is an important mechanism for the regulation of variety aspects of protein function. Over the last decades, three classes of lipid modifications have been increasingly studied. The co-regulation of these different lipid modifications is beginning to be noticed. However, due to the lack of integrated bioinformatics resources, the studies of co-regulatory mechanisms are still very limited. In this...

  20. Ion Channels Induced by Antimicrobial Agents in Model Lipid Membranes are Modulated by Plant Polyphenols Through Surrounding Lipid Media.

    Science.gov (United States)

    Efimova, Svetlana S; Zakharova, Anastasiia A; Medvedev, Roman Ya; Ostroumova, Olga S

    2018-03-16

    The potential therapeutic applications of plant polyphenols in various neurological, cardiovascular, metabolic and malignant disorders determine the relevance of studying the molecular mechanisms of their action on the cell membranes. Here, the quantitative changes in the physical parameters of model bilayer lipid membranes upon the adsorption of plant polyphenols were evaluated. It was shown that butein and naringenin significantly decreased the intrinsic dipole potential of cholesterol-free and cholesterol-enriched membranes. Cardamonin, 4'-hydroxychalcone, licochalcone A and liquiritigenin demonstrated the average efficiency, while resveratrol did not characterized by the ability to modulate the bilayer electrostatics. At the same time, the tested polyphenols affected melting of phospholipids with saturated acyl chains. The effects were attributed to the lipid disordering and a promotion of the positive curvature stress. According to DSC data and results of measurements of the threshold voltages that cause bilayer breakdown licochalcone A is the most effective agent. Furthermore, the role of the polyphenol induced changes in the electric and elastic properties of lipid host in the regulation of reconstituted ion channels was examined. The ability of the tested polyphenols to decrease the conductance of single ion channels produced by the antifungal cyclic lipopeptide syringomycin E was in agreement with their effects on the dipole potential of the lipid bilayers. The greatest effect of licochalcone A on the steady-state membrane conductance induced by the antifungal polyene macrolide antibiotic nystatin correlated with its greatest efficacy to induce the positive curvature stress. We also found that butein and naringenin bind specifically to a single pore formed by α-hemolysin from Staphylococcus aureus.

  1. Using fluorescent lipids in live zebrafish larvae: From imaging whole animal physiology to subcellular lipid trafficking.

    Science.gov (United States)

    Anderson, J L; Carten, J D; Farber, S A

    2016-01-01

    Lipids serve essential functions in cells as signaling molecules, membrane components, and sources of energy. Defects in lipid metabolism are implicated in a number of pandemic human diseases, including diabetes, obesity, and hypercholesterolemia. Many aspects of how fatty acids and cholesterol are absorbed and processed by intestinal cells remain unclear and present a hurdle to developing approaches for disease prevention and treatment. Numerous studies have shown that the zebrafish is an excellent model for vertebrate lipid metabolism. In this chapter, we review commercially available fluorescent lipids that can be deployed in live zebrafish to better understand lipid signaling and metabolism. In this chapter, we present criteria one should consider when selecting specific fluorescent lipids for the study of digestive physiology or lipid metabolism in larval zebrafish. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Unravel lipid accumulation mechanism in oleaginous yeast through single cell systems biology study

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Shiyou; Xiaoliang, Xie

    2017-12-18

    transcriptional profiles at the single-cell level, as follows: 1) We developed hyperspectral Stimulated Raman Scattering (hsSRS) microscope tailored for fast chemical imaging in complex biological systems. It features high numerical aperture of 1.4 for better spatial resolution and reduced cross-phase modulation. The femtosecond infrared laser was selected for deeper penetration and less photodamage for longer in-situ imaging time. hsSRS was achieved through spectral focusing where two femtosecond laser beams were linearly chirped to create overlapping pulses in time domain. We achieved transformed limited spectral resolution of ~15cm for superior clarity in identifying different types of lipids. A set of sophisticated algorithms based on Multivariate Curve Resolution (MCR) was developed to analyze yeast images and track droplets. 2) Lipid production was carried out on selected oleaginous yeast strains. Lipid accumulation was studied in R. glutinis and Y. lipolytica grown in regular and nitrogen starvation media. hsSRS imaging of lipid droplets showed considerable variation among individual Y. lipolytica cells regarding volume and composition, while the R. glutins lipid droplet showed similar Raman response representing more homogenous lipid production. hsSRS analysis revealed the spatial distribution of two major lipids-TAG and sterol ester (SE)- where TAG formed cores were surrounded by SE shells. Significantly elevated level of SE/TAG was observed at cellular and sub-cellular levels which could be attributed to epigenetic variation in cell development. 3) Yeast growth conditions were studied based on their lipid droplets formation. Optimal condition was found in two-stage grown media where the yeast was grown in regular YEPD and transferred to nitrogen starvation media after maturation. The volume and composition of lipid droplets vary significantly depending on the availability of nitrogen source. Large number of cells have been fast screened and analyzed by custom

  3. Study of serum lipids in leprosy

    Directory of Open Access Journals (Sweden)

    Gupta Anju

    2002-01-01

    Full Text Available Fifty fresh and untreated patients of leprosy constituted the study group. Fifty, age and sex matched healthy individuals formed the controls. Ridly and Jopling system of classification was used in the study. Majority i.e 21 cases were of BT group, 12 of BB, 7 of BL, 9 of LL and one case was of TT leprosy. The serum triglyceride level was lower than normal in TT, showed no alteration in BT or BB and was insignificantly increased in bL and LL patients. The total cholesterol was lowerthan normal in TT, showed no alteration in BT or BB and was insignificantly increased in Bland LL patients. The total cholesterol was lower than normal in TT, whereas in BT, BB, BL and LL groups the levels were statistically decreased. The HDL cholesterol was within normal range in TT, significantly decreased in BT and LL patients, showed no significant alteration in BB and was insignificantly decreased in BL group. The LDL cholesterol in TT was low but was not so low statistically when compared with the controls, whereas in BT, BB, BL and LL groups the levels were statistically decreased. The VLDL cholesterol was within normal range in TT and BT, was raised insignificantly in 3 of 12 cases of BB, was within normal range in BL and in LL leprosy it was raised in one out of 9 cases. In the absence of any derangement of liver function tests, it can be concluded that leprosy per se leads to alterations in lipid metabolism. However, no correlation could be established between the group/type of leprosy, bacterial indices and levels of different lipid fractions in the present study.

  4. Study on the correlation of serum lipid metabolism and central retinal artery hemodynamics with diabetic retinopathy

    Institute of Scientific and Technical Information of China (English)

    Ran-Yang Guo

    2016-01-01

    Objective:To explore the correlation of serum lipid metabolism and central retinal artery (CRA) hemodynamics with diabetic retinopathy (DR).Methods:A total of 120 patients with type 2 diabetes who were admitted in our hospital from May, 2015 to May, 2016 were included in the study and divided into NDR group (non-diabetic retinopathy), NPR group (non-proliferative retinopathy), and PR group (proliferative retinopathy) with 40 cases in each group according to DR clinical staging. Moreover, 50 healthy individuals who came for physical examinations were served as the control group. The full automatic biochemical analyzer was used to detect the levels of TG, TC, LDL-C, and HDL-C. The color Doppler flow imaging (CDFI) was used to detect EDV, PSV, RI, and PI of CRA and OA.Results:The levels of TG, TC, and LDL-C in NDG, NPR, and PR groups were gradually increased with the aggravation of retinopathy, HDL-C was reduced, the comparison among the three groups was statistically significant, and the comparison with the control group was statistically significant. EDV, PSV, and PI of CRA and OA in NDG, NPR, and PR groups were gradually increased with the aggravation of retinopathy, RI was reduced, the comparison among the three groups was statistically significant, and the comparison with the control group was statistically significant. Conclusions: The lipid metabolism disorder can promote the occurrence and development of DR. The change of CRA and OA hemodynamics is an important pathological basis for developing DR. Clinical detection of serum lipid level and monitoring of the changes of fundus artery hemocynamic parameters are of great significance in early detecting DR.

  5. Utility of the triglyceride level for predicting incident diabetes mellitus according to the fasting status and body mass index category: the Ibaraki Prefectural Health Study.

    Science.gov (United States)

    Fujihara, Kazuya; Sugawara, Ayumi; Heianza, Yoriko; Sairenchi, Toshimi; Irie, Fujiko; Iso, Hiroyasu; Doi, Mikio; Shimano, Hitoshi; Watanabe, Hiroshi; Sone, Hirohito; Ota, Hitoshi

    2014-01-01

    The levels of lipids, especially triglycerides (TG), and obesity are associated with diabetes mellitus (DM). Although typically measured in fasting individuals, non-fasting lipid measurements play an important role in predicting future DM. This study compared the predictive efficacy of lipid variables according to the fasting status and body mass index (BMI) category. Data were collected for 39,196 nondiabetic men and 87,980 nondiabetic women 40-79years of age who underwent health checkups in Ibaraki-Prefecture, Japan in 1993 and were followed through 2007. The hazard ratios (HRs) for DM in relation to sex, the fasting status and BMI were estimated using a Cox proportional hazards model. A total of 8,867 participants, 4,012 men and 4,855 women, developed DM during a mean follow-up of 5.5 years. TG was found to be an independent predictor of incident DM in both fasting and non-fasting men and non-fasting women. The multivariable-adjusted HR for DM according to the TG quartile (Q) 4 vs. Q1 was 1.18 (95% confidence interval (CI): 1.05, 1.34) in the non-fasting men with a normal BMI (18.5-24.9). This trend was also observed in the non-fasting women with a normal BMI. That is, the multivariable-adjusted HRs for DM for TG Q2, Q3 and Q4 compared with Q1 were 1.07 (95% CI: 0.94, 1.23), 1.17 (95%CI: 1.03, 1.34) and 1.48 (95%CI: 1.30, 1.69), respectively. The fasting and non-fasting TG levels in men and non-fasting TG levels in women are predictive of future DM among those with a normal BMI. Clinicians must pay attention to those individuals at high risk for DM.

  6. Lipid diffusion in the distal and proximal leaflets of supported lipid bilayer membranes studied by single particle tracking

    Science.gov (United States)

    Schoch, Rafael L.; Barel, Itay; Brown, Frank L. H.; Haran, Gilad

    2018-03-01

    Supported lipid bilayers (SLBs) have been studied extensively as simple but powerful models for cellular membranes. Yet, potential differences in the dynamics of the two leaflets of a SLB remain poorly understood. Here, using single particle tracking, we obtain a detailed picture of bilayer dynamics. We observe two clearly separate diffusing populations, fast and slow, that we associate with motion in the distal and proximal leaflets of the SLB, respectively, based on fluorescence quenching experiments. We estimate diffusion coefficients using standard techniques as well as a new method based on the blur of images due to motion. Fitting the observed diffusion coefficients to a two-leaflet membrane hydrodynamic model allows for the simultaneous determination of the intermonolayer friction coefficient and the substrate-membrane friction coefficient, without any prior assumptions on the strengths of the relevant interactions. Remarkably, our calculations suggest that the viscosity of the interfacial water confined between the membrane and the substrate is elevated by ˜104 as compared to bulk water. Using hidden Markov model analysis, we then obtain insight into the transbilayer movement of lipids. We find that lipid flip-flop dynamics are very fast, with half times in the range of seconds. Importantly, we find little evidence for membrane defect mediated lipid flip-flop for SLBs at temperatures well above the solid-to-liquid transition, though defects seem to be involved when the SLBs are cooled down. Our work thus shows that the combination of single particle tracking and advanced hydrodynamic modeling provides a powerful means to obtain insight into membrane dynamics.

  7. Influences of the Structure of Lipids on Thermal Stability of Lipid Membranes

    International Nuclear Information System (INIS)

    Hai Nan-Nan; Zhou Xin; Li Ming

    2015-01-01

    The binding free energy (BFE) of lipid to lipid bilayer is a critical factor to determine the thermal or mechanical stability of the bilayer. Although the molecular structure of lipids has significant impacts on BFE of the lipid, there lacks a systematic study on this issue. In this paper we use coarse-grained molecular dynamics simulation to investigate this problem for several typical phospholipids. We find that both the tail length and tail unsaturation can significantly affect the BFE of lipids but in opposite way, namely, BFE decreases linearly with increasing length, but increases linearly with addition of unsaturated bonds. Inspired by the specific structure of cholesterol which is a crucial component of biomembrane, we also find that introduction of carbo-ring-like structures to the lipid tail or to the bilayer may greatly enhance the stability of the bilayer. Our simulation also shows that temperature can influence the bilayer stability and this effect can be significant when the bilayer undergoes phase transition. These results may be helpful to the design of liposome or other self-assembled lipid systems. (paper)

  8. Effect of gamma radiation on lipids by the TBARS and NMR

    International Nuclear Information System (INIS)

    Silva, Adriana Cristina de Oliveira; Cortez, Marco Antonio Sloboda; Marsico, Eliane Teixeira; Guimaraes, Carlos Frederico; Jesus, Edgar Francisco Oliveira de

    2011-01-01

    The aim of this work was to study the effect of gamma radiation on lipids by TBARS and NMR. The samples of raw whole milk were subjected to gamma radiation from Co 60 in doses of 1, 2 and 3 kGy and the production of rancidity was studied through Nuclear Magnetic Resonance (NMR) and Thiobarbituric Acid Test (2-TBARS). The TBARS values increased according to the intensity of the radiation dose applied at the samples, demonstrating correlation between the radiation dose and the production of lipid oxidation. This was confirmed by NMR with the formation of peaks of aldehydes and ketones that were small and similar in the doses of 1 and 2 kGy. In the dose of 3 kGy, the total degradation of milk fat was observed. A correlation between the NMR and 2-TBA was detected. (author)

  9. Effect of gamma radiation on lipids by the TBARS and NMR

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Adriana Cristina de Oliveira; Cortez, Marco Antonio Sloboda, E-mail: vetdri@gmail.com [Lab. de Inspecao e Tecnologia de Leite e Derivados Lacteos, Faculdade de Medicina Veterinaria, Universidade Federal Fluminense, Niteroi - RJ (Brazil); Marsico, Eliane Teixeira; Guimaraes, Carlos Frederico [Laboratorio de Controle Fisico-Quimico de Produtos de Origem Animal, Faculdade de Medicina Veterinaria, Universidade Federal Fluminense, Niteroi - RJ (Brazil); Jesus, Edgar Francisco Oliveira de [Laboratorio de Instrumentacao Nuclear, Instituto Alberto Luiz Coimbra de Pos-graduacao e Pesquisa de Engenharia, Universidade Federal do Rio de Janeiro, Rio de Janeiro - RJ (Brazil)

    2011-11-15

    The aim of this work was to study the effect of gamma radiation on lipids by TBARS and NMR. The samples of raw whole milk were subjected to gamma radiation from Co{sup 60} in doses of 1, 2 and 3 kGy and the production of rancidity was studied through Nuclear Magnetic Resonance (NMR) and Thiobarbituric Acid Test (2-TBARS). The TBARS values increased according to the intensity of the radiation dose applied at the samples, demonstrating correlation between the radiation dose and the production of lipid oxidation. This was confirmed by NMR with the formation of peaks of aldehydes and ketones that were small and similar in the doses of 1 and 2 kGy. In the dose of 3 kGy, the total degradation of milk fat was observed. A correlation between the NMR and 2-TBA was detected. (author)

  10. Lipidic profile and the level of physical activity of adolescent scholars

    Directory of Open Access Journals (Sweden)

    Renato Canevari Dutra da Silva

    2011-12-01

    Full Text Available Objective: To assess the relationship between lipid profile and physical activity level of adolescent students in Rio Verde-GO, Brazil. Methods: A descriptive and cross-sectionalstudy, conducted in 2006, with a population comprised by 1,229 adolescent students of both genders, aged 15 to 17 years (X = 15.9 years, SD + 0.81, from public and private schools. The level of physical activity was assessed through the International PhysicalActivity Questionnaire (IPAQ. Later, 48 teenagers underwent a lipidogram (lipid profile. Lipid concentrations of total cholesterol (TC, HDL-c (high density lipoprotein and LDL (low density lipoprotein and triglycerides (TGL were determined and assessed according to cutoff points proposed by the III Brazilian Guidelines on dyslipidemias and Guideline of Atherosclerosis, Department of Atherosclerosis of Brazilian Society of Cardiology. Statisticalanalysis was performed by binomial test for proportions and Pearson’s correlation test, adopting p <0.05. Results: Applying IPAQ we found a percentage of 77.7% active adolescents and 22.3% of insufficiently active adolescents, with the highest percentage of active teens inmales (p = 0.0000. Adolescents of both sexes from public network were considered more active than teens from private schools. The lipid profile of the studied adolescents was within normal range. Conclusion: There was no relationship between physical activity level and lipid profile of the adolescents assessed.

  11. Тhe mass-spectrometry studies of the interaction of polyhexamethyleneguanidine with lipids

    OpenAIRE

    A. V. Lysytsya; A. V. Rebriev

    2014-01-01

    In this work the integral components of the cytoplasmic membrane, lecithin and cholesterol were used for mass spectrometry analysis carried out on polyhexamethyleneguanidine (PHMG) mixtures with lipids. The study was performed by mass-spectrometry methods of the MALDI-TOF MS. Our results showed that despite the common use of PHGM polymer derivatives as disinfectants the persistent intermolecular complexes of PHMG oligomers with lipids were not formed. The binding of polycation PHMG with the m...

  12. Hippocampal lipid differences in Alzheimer's disease: a human brain study using matrix?assisted laser desorption/ionization?imaging mass spectrometry

    OpenAIRE

    Mendis, Lakshini H. S.; Grey, Angus C.; Faull, Richard L. M.; Curtis, Maurice A.

    2016-01-01

    Abstract Introduction Alzheimer's disease (AD), the leading cause of dementia, is pathologically characterized by ??amyloid plaques and tau tangles. However, there is also evidence of lipid dyshomeostasis?mediated AD pathology. Given the structural diversity of lipids, mass spectrometry is a useful tool for studying lipid changes in AD. Although there have been a few studies investigating lipid changes in the human hippocampus in particular, there are few reports on how lipids change in each ...

  13. Effect of estrogen deficiency on the lipid profile in women in different age periods

    Directory of Open Access Journals (Sweden)

    Neyfeld I.V.

    2014-09-01

    Full Text Available The aim of the study is to evaluate influence of estrogen deficiency on lipid profile in women of different age. Material and Methods. 189 women with normal body weight: 44 women with premature menopause (aged <40 years, 69 women with early menopause (aged 40-45 years, and 76 women with natural menopause (aged 46-55 years have been studied. In all women identification of clinical status has been performed during clinical examination. Results. It is shown that increasing age associated with increasing total cholesterol, triglycerides, low-density lipoprotein (LDL, very low density lipoproteins (VLDL (p<0.05. We have not observed a significant association between age and level of high-density lipoprotein (HDL (p=0.117. According with increased age, atherogenic index of plasma (AIP increases from initial -0.17±0.09 (M±o to 0.09±0.47 (p<0.05 in women with premature menopause, and to 0.14±0.21 (p<0.05 in other women. Final level of AIP was similar between women aged 40-45 years and women aged 46-55 years (p=0.084. Conclusion. Lipid metabolism disorders were assessed in 73.5% of women with estrogen deficiency. According to the age factor the rate of women with normal lipid metabolism decreases (x2=10,165, p=0.026.

  14. Lipid catabolism of invertebrate predator indicates widespread wetland ecosystem degradation

    Science.gov (United States)

    Anteau, Michael J.; Afton, Alan D.

    2011-01-01

    Animals frequently undergo periods when they accumulate lipid reserves for subsequent energetically expensive activities, such as migration or breeding. During such periods, daily lipid-reserve dynamics (DLD) of sentinel species can quantify how landscape modifications affect function, health, and resilience of ecosystems. Aythya affinis (Eyton 1838; lesser scaup; diving duck) are macroinvertebrate predators; they migrate through an agriculturally dominated landscape in spring where they select wetlands with the greatest food density to refuel and accumulate lipid reserves for subsequent reproduction. We index DLD by measuring plasma-lipid metabolites of female scaup (n = 459) that were refueling at 75 spring migration stopover areas distributed across the upper Midwest, USA. We also indexed DLD for females (n = 44) refueling on a riverine site (Pool 19) south of our upper Midwest study area. We found that mean DLD estimates were significantly (P<0.05) less than zero in all ecophysiographic regions of the upper Midwest, and the greatest negative value was in the Iowa Prairie Pothole region (-31.6). Mean DLD was 16.8 at Pool 19 and was markedly greater than in any region of the upper Midwest. Our results indicate that females catabolized rather than stored lipid reserves throughout the upper Midwest. Moreover, levels of lipid catabolism are alarming, because scaup use the best quality wetlands available within a given stopover area. Accordingly, these results provide evidence of wetland ecosystem degradation across this large agricultural landscape and document affects that are carried-up through several trophic levels. Interestingly, storing of lipids by scaup at Pool 19 likely reflects similar ecosystem perturbations as observed in the upper Midwest because wetland drainage and agricultural runoff nutrifies the riverine habitat that scaup use at Pool 19. Finally, our results underscore how using this novel technique to monitor DLD, of a carefully selected sentinel

  15. Lipid catabolism of invertebrate predator indicates widespread wetland ecosystem degradation.

    Directory of Open Access Journals (Sweden)

    Michael J Anteau

    Full Text Available Animals frequently undergo periods when they accumulate lipid reserves for subsequent energetically expensive activities, such as migration or breeding. During such periods, daily lipid-reserve dynamics (DLD of sentinel species can quantify how landscape modifications affect function, health, and resilience of ecosystems. Aythya affinis (Eyton 1838; lesser scaup; diving duck are macroinvertebrate predators; they migrate through an agriculturally dominated landscape in spring where they select wetlands with the greatest food density to refuel and accumulate lipid reserves for subsequent reproduction. We index DLD by measuring plasma-lipid metabolites of female scaup (n = 459 that were refueling at 75 spring migration stopover areas distributed across the upper Midwest, USA. We also indexed DLD for females (n = 44 refueling on a riverine site (Pool 19 south of our upper Midwest study area. We found that mean DLD estimates were significantly (P<0.05 less than zero in all ecophysiographic regions of the upper Midwest, and the greatest negative value was in the Iowa Prairie Pothole region (-31.6. Mean DLD was 16.8 at Pool 19 and was markedly greater than in any region of the upper Midwest. Our results indicate that females catabolized rather than stored lipid reserves throughout the upper Midwest. Moreover, levels of lipid catabolism are alarming, because scaup use the best quality wetlands available within a given stopover area. Accordingly, these results provide evidence of wetland ecosystem degradation across this large agricultural landscape and document affects that are carried-up through several trophic levels. Interestingly, storing of lipids by scaup at Pool 19 likely reflects similar ecosystem perturbations as observed in the upper Midwest because wetland drainage and agricultural runoff nutrifies the riverine habitat that scaup use at Pool 19. Finally, our results underscore how using this novel technique to monitor DLD, of a carefully

  16. The Impact of Cardiorespiratory Fitness on Age-Related Lipids and Lipoproteins

    Science.gov (United States)

    Park, Yong-Moon Mark; Sui, Xuemei; Liu, Junxiu; Zhou, Haiming; Kokkinos, Peter F.; Lavie, Carl J.; Hardin, James W.; Blair, Steven N.

    2015-01-01

    Background Evidence on the effect of cardiorespiratory fitness (CRF) on age-related longitudinal changes of lipids and lipoproteins is scarce. Objectives This study sought to assess the longitudinal, aging trajectory of lipids and lipoproteins for the life course in adults, and to determine whether CRF modifies the age-associated trajectory of lipids and lipoproteins. Methods Data came from 11,418 men, 20 to 90 years of age, without known high cholesterol, high triglycerides, cardiovascular disease, and cancer at baseline and during follow-up from the Aerobics Center Longitudinal Study. There were 43,821 observations spanning 2 to 25 (mean 3.5) health examinations between 1970 and 2006. CRF was quantified by a maximal treadmill exercise test. Marginal models using generalized estimating equations were applied. Results Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and non-high-density lipoprotein cholesterol (non-HDL-C) presented similar inverted U-shaped quadratic trajectories with aging: gradual increases were noted until the mid-40s to early 50s, with subsequent declines (all p lipoproteins in young to middle-aged men than in older men. Conclusions Our investigation reveals a differential trajectory of lipids and lipoproteins with aging according to CRF in healthy men, and suggests that promoting increased CRF levels may help delay the development of dyslipidemia. PMID:25975472

  17. The effect of cardiorespiratory fitness on age-related lipids and lipoproteins.

    Science.gov (United States)

    Park, Yong-Moon Mark; Sui, Xuemei; Liu, Junxiu; Zhou, Haiming; Kokkinos, Peter F; Lavie, Carl J; Hardin, James W; Blair, Steven N

    2015-05-19

    Evidence on the effect of cardiorespiratory fitness (CRF) on age-related longitudinal changes of lipids and lipoproteins is scarce. This study sought to assess the longitudinal aging trajectory of lipids and lipoproteins for the life course in adults and to determine whether CRF modifies the age-associated trajectory of lipids and lipoproteins. Data came from 11,418 men, 20 to 90 years of age, without known high cholesterol, high triglycerides, cardiovascular disease, and cancer at baseline and during follow-up from the Aerobics Center Longitudinal Study. There were 43,821 observations spanning 2 to 25 health examinations (mean 3.5 examinations) between 1970 and 2006. CRF was quantified by a maximal treadmill exercise test. Marginal models using generalized estimating equations were applied. Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides, and non-high-density lipoprotein cholesterol (non-HDL-C) presented similar inverted U-shaped quadratic trajectories with aging: gradual increases were noted until age mid-40s to early 50s, with subsequent declines (all p lipoproteins in young to middle-age men than in older men. Our investigation reveals a differential trajectory of lipids and lipoproteins with aging according to CRF in healthy men and suggests that promoting increased CRF levels may help delay the development of dyslipidemia. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  18. Integrative computational approach for genome-based study of microbial lipid-degrading enzymes.

    Science.gov (United States)

    Vorapreeda, Tayvich; Thammarongtham, Chinae; Laoteng, Kobkul

    2016-07-01

    Lipid-degrading or lipolytic enzymes have gained enormous attention in academic and industrial sectors. Several efforts are underway to discover new lipase enzymes from a variety of microorganisms with particular catalytic properties to be used for extensive applications. In addition, various tools and strategies have been implemented to unravel the functional relevance of the versatile lipid-degrading enzymes for special purposes. This review highlights the study of microbial lipid-degrading enzymes through an integrative computational approach. The identification of putative lipase genes from microbial genomes and metagenomic libraries using homology-based mining is discussed, with an emphasis on sequence analysis of conserved motifs and enzyme topology. Molecular modelling of three-dimensional structure on the basis of sequence similarity is shown to be a potential approach for exploring the structural and functional relationships of candidate lipase enzymes. The perspectives on a discriminative framework of cutting-edge tools and technologies, including bioinformatics, computational biology, functional genomics and functional proteomics, intended to facilitate rapid progress in understanding lipolysis mechanism and to discover novel lipid-degrading enzymes of microorganisms are discussed.

  19. Blood lipids analysis in patients with hepatitis and hepatic fibrosis

    International Nuclear Information System (INIS)

    Si Jianhong

    2007-01-01

    Objective: To investigate the correlationship between blood hepatic fibrosis markers and blood lipids levels. Methods: Serum hepatic fibrosis markers (HA, PC III, IV-C, LN) levels were determined with RIA and serum lipids (TG, TCh HDL; LDL, apoA1, apoB) were measured with biochemical methods in 98 patients with hepatitis in various stages and 50 controls. Liver biopsy was done in all the hepatitis patients. Results: Hepatic fibrosis was classified into 5 grades (S0-S4) according to the pathology shown in the biopsy specimen. The serum lipid levels decreased along with the increase of severity of fibrosis from S0 to S4. Levels in S4 patients were significantly lower than those in controls (P 0.05). Conclusion: The serum hepatic fibrosis markers levels increased and lipids levels decreased along with the progress of hepatitis from acute to cirrhosis. (authors)

  20. Physical activity, high density lipoprotein cholesterol and other lipids levels, in men and women from the ATTICA study

    Directory of Open Access Journals (Sweden)

    Papaioannou Ioanna

    2003-06-01

    Full Text Available Abstract Background Physical activity has long been associated with reduced risk of coronary heart disease (CHD. In this work we evaluated the effect of physical activity on lipid levels, in a sample of cardiovascular disease free people. Methods The ATTICA study is a population – based cohort that has randomly enrolled 2772 individuals, stratified by age – gender (according to the census 2001, from the greater area of Athens, during 2001–2002. Of them, 1376 were men (45 ± 12 years old, range: 18 – 86 and 1396 women (45 ± 13 years old, range: 18 – 88. We assessed the relationship between physical activity status (measured in kcal/min expended per day and several lipids, after taking into account the effect of several characteristics of the participants. Results 578 (42% men and 584 (40% women were classified as physically active. Compared to sedentary physically active women had significantly lower levels of total serum cholesterol (p Conclusions Substantial independent increases in HDL-cholesterol and apolipoprotein A1 concentrations were observed in women, but not in men, in a Mediterranean cohort.

  1. What are the effects of psychological stress and physical work on blood lipid profiles?

    Science.gov (United States)

    Assadi, Seyedeh Negar

    2017-05-01

    Blood lipids disorders are prevalent in the world. Some of their risk factors are modifiable such as mental and physical stress which existed in some places such as work environment.Objective of this study was to determine the effects of psychological and physical stress on the lipid profiles. It was a historical cohort study. The people who were employed as general worker were participated. The study was conducted with flexible interview for getting history, lipid profile examination, and a checklist including occupational and nonoccupational risk factors and using the health issues. According to the type of stress exposures, the study population was divided into 5 groups. Groups were followed for lipid profiles. These groups were exposed to psychological stress, physical stress or both of them; mild psychological stress (group 1), mild physical work without psychological stress (group 2), mild psychological stress and mild physical work (group 3), moderate physical work without psychological stress (group 4), and heavy physical work without psychological stress (group 5). Data were analyzed with SPSS 16. ANOVA, χ, and exact test were calculated with considering P less than 45 mg/dL was 14.61 (8.31-25.68) in group 1 and 16.00 (8.30-30.83) in group 3. After multinomial logistic regression they had significant differences. Psychological stress was a risk factor for lipid disorders, and suitable physical activity was protective in this situation.

  2. Protective effect of morin on lipid peroxidation and lipid profile in ammonium chloride-induced hyperammonemic rats

    Directory of Open Access Journals (Sweden)

    S Subash

    2012-04-01

    Full Text Available Objective: To evaluated the protective effects of morin (3, 5, 7, 2', 4'-pentahydroxyflavone on lipid peroxidation and lipid levels during ammonium chloride (AC induced hyperammonemia in experimental rats. Methods: Thirty two male albino Wistar rats, which are weighing between 180-200 g were used for the study. The hyperammonemia was induced by administration of 100 mg/kg body weight (i.p. thrice in a week of AC for 8 weeks. Rats were treated with morin at dose (30 mg/kg body weight via intragastric intubations together with AC. At the end of experimental duration, blood ammonia, plasma urea, lipid peroxidation indices [thiobarbituric acid reactive substances, hydroperoxides and lipid levels (cholesterol, triglycerides, free fatty acids and phospholipids] in serum and tissues were analysed to evaluate the antiperoxidative and antilipidemic effects of morin. Results: Ammonia, urea, lipid peroxidative indices and lipid levels were significantly increased in AC administered group. Morin treatment resulted in positive modulation of ammonia, urea, lipid peroxidative indices and lipid levels. Morin administration to normal rats did not exhibit any significant changes in any of the parameters studied. Conclusions: It can be concluded that the beneficial effect of morin on ammonia, urea, lipid peroxidative indices and lipid levels could be due to its antioxidant property.

  3. Preoperative serum lipid profile and outcome in nonmetastatic colorectal cancer

    Directory of Open Access Journals (Sweden)

    Ting-Ting Hong

    2016-12-01

    Full Text Available Objective: A large portion of non-metastatic colorectal cancers (non-mCRCs recur after curative surgery. In addition to the traditional tumor-related factors, host-related factors are also required to accurately predict prognosis. A few studies have shown an association between the serum lipid profile and the survival and treatment response of patients with colorectal cancer. Methods: We retrospectively evaluated the prognostic significance of the preoperative serum lipid profile [total cholesterol (TC, triglyceride (TG, low-density lipoprotein cholesterol (LDL-C, and high-density lipoprotein cholesterol (HDL-C] in patients with non-mCRC treated with curative surgery. The Spearman rank correlation test was used to analyze associations between lipid levels and categorical variables. Lipid levels were modeled as four equal-sized quartiles based on the distribution among the whole cohort. Kaplan-Meier curves were used to estimate survival probabilities, and the log-rank test was used to detect differences between them. Multivariate fractional polynomial (MFP analysis was used to model any non-linear effects and avoid categorization. To evaluate the added prognostic value of lipids, the predictive power of two models (with and without lipids as covariates was compared by using Harrell's C-statistic and the Akaike information criterion (AIC. Results: A total of 266 patients with non-mCRC were enrolled in the present study. Spearman rank correlation test showed that TG levels inversely correlated with N stage (r = −0.20, P = 0.00 and Tumor-Node-Metastasis (TNM stage (r = −0.19, P = 0.00. HDL-C levels positively correlated with perineural invasion (PNI (r = 0.15, P = 0.02, and LDL-C levels inversely correlated with lymphovascular invasion (LVI (r = −0.12, P = 0.04. None of the four lipids predicted overall survival (OS in univariate or multivariate analyses adjusted for age, gender, T stage, N stage, TNM stage

  4. Genetic architecture of circulating lipid levels

    DEFF Research Database (Denmark)

    Demirkan, Ayşe; Amin, Najaf; Isaacs, Aaron

    2011-01-01

    Serum concentrations of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TGs) and total cholesterol (TC) are important heritable risk factors for cardiovascular disease. Although genome-wide association studies (GWASs) of circulating lipid...... the ENGAGE Consortium GWAS on serum lipids, were applied to predict lipid levels in an independent population-based study, the Rotterdam Study-II (RS-II). We additionally tested for evidence of a shared genetic basis for different lipid phenotypes. Finally, the polygenic score approach was used to identify...... an alternative genome-wide significance threshold before pathway analysis and those results were compared with those based on the classical genome-wide significance threshold. Our study provides evidence suggesting that many loci influencing circulating lipid levels remain undiscovered. Cross-prediction models...

  5. Synthesis of Lipidated Proteins.

    Science.gov (United States)

    Mejuch, Tom; Waldmann, Herbert

    2016-08-17

    Protein lipidation is one of the major post-translational modifications (PTM) of proteins. The attachment of the lipid moiety frequently determines the localization and the function of the lipoproteins. Lipidated proteins participate in many essential biological processes in eukaryotic cells, including vesicular trafficking, signal transduction, and regulation of the immune response. Malfunction of these cellular processes usually leads to various diseases such as cancer. Understanding the mechanism of cellular signaling and identifying the protein-protein and protein-lipid interactions in which the lipoproteins are involved is a crucial task. To achieve these goals, fully functional lipidated proteins are required. However, access to lipoproteins by means of standard expression is often rather limited. Therefore, semisynthetic methods, involving the synthesis of lipidated peptides and their subsequent chemoselective ligation to yield full-length lipoproteins, were developed. In this Review we summarize the commonly used methods for lipoprotein synthesis and the development of the corresponding chemoselective ligation techniques. Several key studies involving full-length semisynthetic lipidated Ras, Rheb, and LC3 proteins are presented.

  6. Stability of total nutrient admixtures with lipid injectable emulsions in glass versus plastic packaging.

    Science.gov (United States)

    Driscoll, David F; Silvestri, Anthony P; Bistrian, Bruce R; Mikrut, Bernard A

    2007-02-15

    The physical stability of two emulsions compounded as part of a total nutrient admixture (TNA) was studied in lipids packaged in either glass or plastic containers. Five weight-based adult TNA formulations that were designed to meet the full nutritional needs of adults with body weights between 40 and 80 kg were studied. Triplicate preparations of each TNA were assessed over 30 hours at room temperature by applying currently proposed United States Pharmacopeia (USP) criteria for mean droplet diameter, large-diameter tail, and globule-size distribution (GSD) for lipid injectable emulsions. In accordance with conditions set forth in USP chapter 729, the higher levels of volume-weighted percent of fat exceeding 5 microm (PFAT(5)) should not exceed 0.05% of the total lipid concentration. Significant differences were noted among TNA admixtures based on whether the lipid emulsion product was manufactured in glass or plastic. The plastic-contained TNAs failed the proposed USP methods for large-diameter fat globules in all formulations from the outset, and 60% had significant growth in large-diameter fat globules over time. In contrast, glass-contained TNAs were stable throughout and in all cases would have passed proposed USP limits. Certain lipid injectable emulsions packaged in plastic containers have baseline abnormal GSD profiles compared with those packaged in glass containers. When used to compound TNAs, the abnormal profile worsens and produces less stable TNAs than those compounded with lipid injectable emulsions packaged in glass containers.

  7. Effect of lipid composition and packing on the adsorption of apolipoproteins to lipid monolayers

    International Nuclear Information System (INIS)

    Ibdah, J.A.; Lund-Katz, S.; Phillips, M.C.

    1987-01-01

    The monolayer system has been used to study the effects of lipoprotein surface lipid composition and packing on the affinities of apolipoproteins for the surfaces of lipoprotein particles. The adsorption of apolipoproteins injected beneath lipid monolayers prepared with pure lipids or lipoprotein surface lipids is evaluated by monitoring the surface pressure of the film and the surface concentration (Gamma) of 14 C-labelled apolipoprotein. At a given initial film pressure (π/sub i/) there is a higher adsorption of human apo A-I to unsaturated phosphatidylcholine (PC) monolayers compared to saturated PC monolayers (e.g., at π/sub i/ = 10 mN/m, Gamma = 0.35 and 0.06 mg/m 2 for egg PC and distearoyl PC, respectively, with 3 x 10 -4 mg/ml apo A-I in the subphase). In addition, adsorption of apo A-I is less to an egg sphingomyelin monolayer than to an egg PC monolayer. The adsorption of apo A-I to PC monolayers is decreased by addition of cholesterol. Generally, apo A-I adsorption diminishes as the lipid molecular area decreases. Apo A-I adsorbs more to monolayers prepared with HDL 3 surface lipids than with LDL surface lipids. These studies suggest that lipoprotein surface lipid composition and packing are crucial factors influencing the transfer and exchange of apolipoproteins among various lipoprotein classes during metabolism of lipoprotein particles

  8. [Lipids of Aureobasidium (Pullularia) pullulans].

    Science.gov (United States)

    Elinov, N P; Iurlova, N A; Efimova, T P

    1975-01-01

    Fractional composition of free and bound lipids was studied in Aureobasidium (Pullularia) pullulans 8 by preparative TLC on Silufol. Bound lipids contained a fraction (27.76 +/- 0.5%) of dark brown colour, similar to melanin. The composition of fatty acids was studied by GLC. The following fatty acids were identified and determined quantitatively: C12:0, C14:0, C15:0, C16:0, C18:0, C18:1+C15:2. The following fatty acids predominated in free and bound lipids: C16:0, C18:1+C18:2. The ratio between unsaturated and saturated fatty acids in all fractions of free and bound lipids was more than unity. The following parameters were determined for lipids; ester number (173.89 and 178.53); iodine number (44.1 and 33.10), and saponification number (181.17 and 206.03) (the values are given for free and bound lipids, respectively).

  9. Shift working and risk of lipid disorders: A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Shoushtarizadeh Payman

    2006-04-01

    Full Text Available Abstract Background previous studies have indicated on association between shift work and lipid profile disturbances. Lipid profile disturbances could be due to internal desynchronization. The aim of this study was to analyze whether there is relationship between shift work and serum lipids, fasting blood glucose and hypertension. Results A total of 424 rail road workers between the ages of 21 and 64 years in this study filled out a questionnaire, and total cholesterol, triglyceride and HDL-C concentration were measured after 12-hours fasting. Association between shift work and biochemical variables and blood pressure were measured. The X2 and fisher's exact test was used for comparing the qualitative variables and for quantitative variables with normal distribution we used the parametric tests. Odds ratio (OR with the 95% confidence interval (95% CI was used for comparing the proportions of risk variables. Sub-populations in this study were consisting of 158 (37.3% shift workers and 266 (62.7% day workers. High levels of total cholesterol (> 200 mg/dl and LDL-cholesterol (> 130 mg/dl were significantly more prevalent in nearly all groups of shift workers irrespective of age. But there is no differences in the serum levels of triglyceride, HDL-C, fasting blood glucose and blood pressure between shift workers and day workers. Adjusted Odd's ratio for the effect of shift working on high serum total cholesterol and LDL-C level were 2.11(95%CI: 1.33–3.36 and 1.76(95%CI: 1.09–2.83, respectively. Conclusion This study showed that high serum total cholesterol and LDL-C level were more common in shift workers than in day workers. This finding persisted after adjustment was made for age and food type. But there was no difference in the prevalence of HDL-C, triglyceride, fasting blood glucose and hypertension between shift working and day working. It was concluded that shift work is a risk factor for lipid profile disturbances.

  10. Assessment of lipid metabolism in thyroid dysfunction

    Directory of Open Access Journals (Sweden)

    V. G. Kadzharyan

    2014-02-01

    Full Text Available 1. Actuality According to WHO Thyroid dysfunction is one of the most prevalent in humans and is one of the risk factors of cardiovascular diseases. Hypothyroidism affects the mechanisms of potentiation of cardiovascular risk factors, suggesting the need to study the level of the blood lipids in all patients with thyroid dysfunction. 2. The purpose of this study. To define features of lipid metabolism, depending on the functional state of the thyroid gland. 3. Material and methods. The study included 95 patients, mean age was 49,8 ± 12,9 years. 74 of them were women (78% and 21 - men (22%. In accordance with the purpose of the work 3 groups of subjects were formed. I-st group - 35 patients with hypothyroidism, mean age 52,5 ± 10,3 years, II-nd group - 37 patients with hyperthyroidism, the average age was 45,1 ± 13 years, III (control group - 23 patients with euthyroid, mean age 53,9 ± 14,8 years. Levels of TSH, triiodothyronine, thyroxine, microsomal antibodies to thyroglobulin and thyroid peroxidase were evaluated for total and biochemical analysis. To determine the type of hyperlipoproteinemia Fredrickson, 1967 recommendations were used. 4. Results of the study Lipid profile parameters in the I-st group compared with the control were even higher. Cholesterol increased up to 6,9% (p <0,005, Tg - 8,6% (p <0,005, β -DP - 6,8% (p <0,5, in comparison with the II-nd: cholesterol - 56% (p <0,005, TG - 55% (p <0,005 and β-PL 44% (p <0.5. In group II rates were lower than in the III- cholesterol - 8% (p <0,005, Tg 8,3% (p <0,005 and β-PL 6,5% (p <0,5. Patients from the I-st group had the following distribution of hyperlipidemia (Fredrickson, 1967.: I type - 10 patients (29%; IIb type - 15 subjects (43%; IIa type - 9 subjects (26%; IV type - 1 patient (2%. The correlation dependence of TSH and cholesterol (r = +0,37, p <0,05, TG (r = +0,25, p <0,05, β-PL (r = +0,74, p <0.05, TG AT (r = +0,55, p <0,05, the level of bilirubin (r = +0,29, p <0

  11. Single Lipid Molecule Dynamics on Supported Lipid Bilayers with Membrane Curvature

    Directory of Open Access Journals (Sweden)

    Philip P. Cheney

    2017-03-01

    Full Text Available The plasma membrane is a highly compartmentalized, dynamic material and this organization is essential for a wide variety of cellular processes. Nanoscale domains allow proteins to organize for cell signaling, endo- and exocytosis, and other essential processes. Even in the absence of proteins, lipids have the ability to organize into domains as a result of a variety of chemical and physical interactions. One feature of membranes that affects lipid domain formation is membrane curvature. To directly test the role of curvature in lipid sorting, we measured the accumulation of two similar lipids, 1,2-Dihexadecanoyl-sn-glycero-3-phosphoethanolamine (DHPE and hexadecanoic acid (HDA, using a supported lipid bilayer that was assembled over a nanopatterned surface to obtain regions of membrane curvature. Both lipids studied contain 16 carbon, saturated tails and a head group tag for fluorescence microscopy measurements. The accumulation of lipids at curvatures ranging from 28 nm to 55 nm radii was measured and fluorescein labeled DHPE accumulated more than fluorescein labeled HDA at regions of membrane curvature. We then tested whether single biotinylated DHPE molecules sense curvature using single particle tracking methods. Similar to groups of fluorescein labeled DHPE accumulating at curvature, the dynamics of single molecules of biotinylated DHPE was also affected by membrane curvature and highly confined motion was observed.

  12. Lipid order, saturation and surface property relationships: a study of human meibum saturation.

    Science.gov (United States)

    Mudgil, Poonam; Borchman, Douglas; Yappert, Marta C; Duran, Diana; Cox, Gregory W; Smith, Ryan J; Bhola, Rahul; Dennis, Gary R; Whitehall, John S

    2013-11-01

    Tear film stability decreases with age however the cause(s) of the instability are speculative. Perhaps the more saturated meibum from infants may contribute to tear film stability. The meibum lipid phase transition temperature and lipid hydrocarbon chain order at physiological temperature (33 °C) decrease with increasing age. It is reasonable that stronger lipid-lipid interactions could stabilize the tear film since these interactions must be broken for tear break up to occur. In this study, meibum from a pool of adult donors was saturated catalytically. The influence of saturation on meibum hydrocarbon chain order was determined by infrared spectroscopy. Meibum is in an anhydrous state in the meibomian glands and on the surface of the eyelid. The influence of saturation on the surface properties of meibum was determined using Langmuir trough technology. Saturation of native human meibum did not change the minimum or maximum values of hydrocarbon chain order so at temperatures far above or below the phase transition of human meibum, saturation does not play a role in ordering or disordering the lipid hydrocarbon chains. Saturation did increase the phase transition temperature in human meibum by over 20 °C, a relatively high amount. Surface pressure-area studies showing the late take off and higher maximum surface pressure of saturated meibum compared to native meibum suggest that the saturated meibum film is quite molecularly ordered (stiff molecular arrangement) and elastic (molecules are able to rearrange during compression and expansion) compared with native meibum films which are more fluid agreeing with the infrared spectroscopic results of this study. In saturated meibum, the formation of compacted ordered islands of lipids above the surfactant layer would be expected to decrease the rate of evaporation compared to fluid and more loosely packed native meibum. Higher surface pressure observed with films of saturated meibum compared to native meibum

  13. Fat & fabulous: bifunctional lipids in the spotlight.

    Science.gov (United States)

    Haberkant, Per; Holthuis, Joost C M

    2014-08-01

    Understanding biological processes at the mechanistic level requires a systematic charting of the physical and functional links between all cellular components. While protein-protein and protein-nucleic acid networks have been subject to many global surveys, other critical cellular components such as membrane lipids have rarely been studied in large-scale interaction screens. Here, we review the development of photoactivatable and clickable lipid analogues-so-called bifunctional lipids-as novel chemical tools that enable a global profiling of lipid-protein interactions in biological membranes. Recent studies indicate that bifunctional lipids hold great promise in systematic efforts to dissect the elaborate crosstalk between proteins and lipids in live cells and organisms. This article is part of a Special Issue entitled Tools to study lipid functions. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. In vitro synthesis of a lipid-linked trisaccharide involved in synthesis of enterobacterial common antigen

    International Nuclear Information System (INIS)

    Barr, K.; Nunes-Edwards, P.; Rick, P.D.

    1989-01-01

    The heteropolysaccharide chains of enterobacterial common antigen (ECA) are made up of linear trisaccharide repeat units with the structure----3)-alpha-D-Fuc4NAc-(1----4)- beta-D-ManNAcA-(1----4)-alpha-D-GlcNAc-(1----, where Fuc4NAc is 4-acetamido-4,6-dideoxy-D-galactose, ManNAcA is N-acetyl-D-mannosaminuronic acid, and GlcNAc is N-acetyl-D-glucosamine. The assembly of these chains involves lipid-linked intermediates, and both GlcNAc-pyrophosphorylundecaprenol (lipid I) and ManNAcA-GlcNAc-pyrophosphorylundecaprenol (lipid II) are intermediates in ECA biosynthesis. In this study we demonstrated that lipid II serves as the acceptor of Fuc4NAc residues in the assembly of the trisaccharide repeat unit of ECA chains. Incubation of Escherichia coli membranes with UDP-GlcNAc, UDP-[14C]ManNAcA, and TDP-[3H]Fuc4NAc resulted in the synthesis of a radioactive glycolipid (lipid III) that contained both [14C]ManNAcA and [3H]Fuc4NAc. The oligosaccharide moiety of lipid III was identified as a trisaccharide by gel-permeation chromatography, and the in vitro synthesis of lipid III was dependent on prior synthesis of lipids I and II. Accordingly, the incorporation of [3H]Fuc4NAc into lipid III from the donor TDP-[3H]Fuc4NAc was dependent on the presence of both UDP-GlcNAc and UDP-ManNAcA in the reaction mixtures. In addition, the in vitro synthesis of lipid III was abolished by tunicamycin. Direct conversion of lipid II to lipid III was demonstrated in two-stage reactions in which membranes were initially incubated with UDP-GlcNAc and UDP-[14C]ManNAcA to allow the synthesis of radioactive lipid II

  15. Evaluation of seven common lipid associated loci in a large Indian sib pair study.

    Science.gov (United States)

    Rafiq, Sajjad; Venkata, Kranthi Kumar M; Gupta, Vipin; Vinay, D G; Spurgeon, Charles J; Parameshwaran, Smitha; Madana, Sandeep N; Kinra, Sanjay; Bowen, Liza; Timpson, Nicholas J; Smith, George Davey; Dudbridge, Frank; Prabhakaran, Dorairaj; Ben-Shlomo, Yoav; Reddy, K Srinath; Ebrahim, Shah; Chandak, Giriraj R

    2012-11-14

    Genome wide association studies (GWAS), mostly in Europeans have identified several common variants as associated with key lipid traits. Replication of these genetic effects in South Asian populations is important since it would suggest wider relevance for these findings. Given the rising prevalence of metabolic disorders and heart disease in the Indian sub-continent, these studies could be of future clinical relevance. We studied seven common variants associated with a variety of lipid traits in previous GWASs. The study sample comprised of 3178 sib-pairs recruited as participants for the Indian Migration Study (IMS). Associations with various lipid parameters and quantitative traits were analyzed using the Fulker genetic association model. We replicated five of the 7 main effect associations with p-values ranging from 0.03 to 1.97x10(-7). We identified particularly strong association signals at rs662799 in APOA5 (beta=0.18 s.d, p=1.97 x 10(-7)), rs10503669 in LPL (beta =-0.18 s.d, p=1.0 x 10(-4)) and rs780094 in GCKR (beta=0.11 s.d, p=0.001) loci in relation to triglycerides. In addition, the GCKR variant was also associated with total cholesterol (beta=0.11 s.d, p=3.9x10(-4)). We also replicated the association of rs562338 in APOB (p=0.03) and rs4775041 in LIPC (p=0.007) with LDL-cholesterol and HDL-cholesterol respectively. We report associations of five loci with various lipid traits with the effect size consistent with the same reported in Europeans. These results indicate an overlap of genetic effects pertaining to lipid traits across the European and Indian populations.

  16. Lipid Profile in Sudanese Diabetic Patients

    Energy Technology Data Exchange (ETDEWEB)

    Naway, L M. Y. [Sudan Academy of Sciences, Atomic Energy Council, Khartoum (Sudan)

    2011-04-15

    This study composes of two parts, the first one is an experiment to evaluate the level of blood glucose and lipid profile (TC, TG, LDL, HDL and VLDL) among diabetic patients and comparison of the result with non diabetic subjects and the second one is a survey to assess the standards of health care and patients knowledge. The subject were divided into two groups according to insulin requirement. Type 1 is insulin dependent diabetes mellitus and type 2 is non insulin dependent diabetes mellitus and then divided according to gender (males and female) subgroups. The study subjects selected for this study consist of one hundred Sudanese diabetic patients from Ribat University Hospital during January 2009 they had mean age (52{+-}11.063) years,a mean height (165.82{+-}8.573) cm and a mean weight of (70.20{+-}11.203) kg. fifty healthy non diabetic subject were chosen as controls, their mean age (45.72{+-}11.169) years, mean height (167.28{+-}9.450) cm and mean weight (71.02{+-}13.429) kg. Blood glucose and lipid profile total cholesterol (TC), triglycerides (TG), low density lipoprotein (LDL) and high density lipoprotein (HDL) were measured by enzymatic colorimetric methods in both groups, and very low density lipoprotein cholesterol were calculated for each sample. All patients were interviewed and filled out the questionnaire consisted of five parts. The result of the study found highly significant elevated level of blood glucose level among diabetic patients compared to non diabetic subjects. In addition to significant elevated level of serum lipids TC p=0.001, TG p=0.001, LDL p=0.001, and VLDL p=0.001. And decrease in HDL P=0.001 level in diabetic patient compared to non diabetic subjects. Among subgroups (type 1, type 2) diabetic patients glucose level and serum total cholesterol, triglycerides, LDL cholesterol and VLDL cholestrol were significantly higher (p<0.5) while HDL cholestrol was significantly lower when compared to non diabetic subjects. Non statistically

  17. Differential Effect of Plant Lipids on Membrane Organization

    Science.gov (United States)

    Grosjean, Kevin; Mongrand, Sébastien; Beney, Laurent; Simon-Plas, Françoise; Gerbeau-Pissot, Patricia

    2015-01-01

    The high diversity of the plant lipid mixture raises the question of their respective involvement in the definition of membrane organization. This is particularly the case for plant plasma membrane, which is enriched in specific lipids, such as free and conjugated forms of phytosterols and typical phytosphingolipids, such as glycosylinositolphosphoceramides. This question was here addressed extensively by characterizing the order level of membrane from vesicles prepared using various plant lipid mixtures and labeled with an environment-sensitive probe. Fluorescence spectroscopy experiments showed that among major phytosterols, campesterol exhibits a stronger ability than β-sitosterol and stigmasterol to order model membranes. Multispectral confocal microscopy, allowing spatial analysis of membrane organization, demonstrated accordingly the strong ability of campesterol to promote ordered domain formation and to organize their spatial distribution at the membrane surface. Conjugated sterol forms, alone and in synergy with free sterols, exhibit a striking ability to order membrane. Plant sphingolipids, particularly glycosylinositolphosphoceramides, enhanced the sterol-induced ordering effect, emphasizing the formation and increasing the size of sterol-dependent ordered domains. Altogether, our results support a differential involvement of free and conjugated phytosterols in the formation of ordered domains and suggest that the diversity of plant lipids, allowing various local combinations of lipid species, could be a major contributor to membrane organization in particular through the formation of sphingolipid-sterol interacting domains. PMID:25575593

  18. A lipid binding domain in sphingosine kinase 2

    International Nuclear Information System (INIS)

    Don, Anthony S.; Rosen, Hugh

    2009-01-01

    The lipid second messenger sphingosine 1-phosphate (S1P) is a critical mediator of cellular proliferation and survival signals, and is essential for vasculogenesis and neurogenesis. S1P formation is catalysed by sphingosine kinases 1 and 2 (Sphk1 and Sphk2). We have found that the endogenous glycolipid sulfatide (3-O-sulfogalactosylceramide) binds to and inhibits the activity of Sphk2 and the closely related ceramide kinase (Cerk), but not Sphk1. Using sulfatide as a probe, we mapped the lipid binding domain to the N-terminus of Sphk2 (residues 1-175), a region of sequence that is absent in Sphk1, but aligns with a pleckstrin homology domain in Cerk. Accordingly, Sphk2 bound to phosphatidylinositol monophosphates but not to abundant cellular phospholipids. Deleting the N-terminal domain reduced Sphk2 membrane localisation in cells. We have therefore identified a lipid binding domain in Sphk2 that is important for the enzyme's sub-cellular localisation.

  19. The relationship between migraine and lipid sub-fractions among individuals without cardiovascular disease: A cross-sectional evaluation in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

    Science.gov (United States)

    Goulart, Alessandra C; Lotufo, Paulo A; Santos, Itamar S; Bittencourt, Márcio S; Santos, Raul D; Blaha, Michael J; Jones, Steven; Toth, Peter P; Kulkarni, Krishnaji; Benseñor, Isabela M

    2018-03-01

    Introduction Recent studies have explored the relationship between dyslipidemia and migraine in a cardiovascular context. Thus, we aimed to evaluate the possible association between lipids, lipoprotein subfractions and migraine according to aura symptoms in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Methods 1,560 women and 1,595 men, without CVD or lipid disorders requiring medication, underwent a baseline clinical assessment. Total-cholesterol and its sub-fractions (LDL, VLDL and HDL subclass cholesterol); triglycerides and triglyceride-rich lipoprotein cholesterol [TRL-C (VLDL 1+2 -C VLDL 3 -C + IDL-C)] were determined by vertical auto profile (VAP). We also calculated logarithmic LDL density ratio [LLDR = ln ((LDL 3 -C + LDL 4 -C)/(LDL 1 -C + LDL 2 -C))], T-Chol/HDL-C and triglycerides/HDL-C ratios. Odds ratios (OR) with 95% confidence intervals (CI) were obtained to evaluate the relationship between lipids tertiles and migraine for both sexes. Results Main findings revealed positive associations between migraine without aura (MO) and the highest tertiles of VLDL-C (OR, 1.61; 95%CI, 1.07-2.40) and TRL-C (OR, 1.55; 95% CI, 1.03-2.34) in women. In men, the highest tertile of VLDL 3 -C (OR, 3.87; 95%CI, 1.23-12.19) was positively associated with MO, as well. Conclusions In middle-aged participants without CVD or lipid disorders requiring medication, the worst lipid profile was determined by the highest levels of TRL-C and their cholesterol-rich remnants in migraineurs without aura for both sexes.

  20. Plasma lipid levels in Alzheimer's disease patients treated by Donepezil hydrochloride: a cross-sectional study.

    Science.gov (United States)

    Adunsky, Abraham; Chesnin, Vladimir; Ravona, Ramit; Harats, Dror; Davidson, Michael

    2004-01-01

    Donepezil hydrochloride is a central acetylcholine esterase inhibitor that is widely used in Alzheimer disease (AD). We have recently observed some differences in lipid profile between occasional cases of Donepezil hydrochloride users (DU) and non-users (DNU). This prompted us to study the levels of plasma lipids in these two groups, cross-sectionally. The medical charts of patients with probable AD were screened for current use of Donepezil hydrochloride and lipids profile, along with other clinical and demographic data. A total number of 105 patients were identified and included in the final analysis. Patients were divided into two groups (DU and DNU). Plasma levels of lipids were recorded. Mann-Whitney or t-test for continuous variables and Fisher exact test for categorical variables were used to test for significant differences between the groups. Regression analysis was applied to identify independently the factors associated with lipid levels. Thirty-three patients were DU and 72 DNU. The two groups differed in terms of age, lipid levels and cognitive level. DU had statistically significant higher levels of triglycerides compared with those not using the drug (P=0.036), higher total cholesterol (Phydrochloride. Alternatively, this may indicate that the effect of the medication may involve lipid metabolism, rather than other proposed mechanisms.

  1. Salt modulates the stability and lipid binding affinity of the adipocyte lipid-binding proteins

    Science.gov (United States)

    Schoeffler, Allyn J.; Ruiz, Carmen R.; Joubert, Allison M.; Yang, Xuemei; LiCata, Vince J.

    2003-01-01

    Adipocyte lipid-binding protein (ALBP or aP2) is an intracellular fatty acid-binding protein that is found in adipocytes and macrophages and binds a large variety of intracellular lipids with high affinity. Although intracellular lipids are frequently charged, biochemical studies of lipid-binding proteins and their interactions often focus most heavily on the hydrophobic aspects of these proteins and their interactions. In this study, we have characterized the effects of KCl on the stability and lipid binding properties of ALBP. We find that added salt dramatically stabilizes ALBP, increasing its Delta G of unfolding by 3-5 kcal/mol. At 37 degrees C salt can more than double the stability of the protein. At the same time, salt inhibits the binding of the fluorescent lipid 1-anilinonaphthalene-8-sulfonate (ANS) to the protein and induces direct displacement of the lipid from the protein. Thermodynamic linkage analysis of the salt inhibition of ANS binding shows a nearly 1:1 reciprocal linkage: i.e. one ion is released from ALBP when ANS binds, and vice versa. Kinetic experiments show that salt reduces the rate of association between ANS and ALBP while simultaneously increasing the dissociation rate of ANS from the protein. We depict and discuss the thermodynamic linkages among stability, lipid binding, and salt effects for ALBP, including the use of these linkages to calculate the affinity of ANS for the denatured state of ALBP and its dependence on salt concentration. We also discuss the potential molecular origins and potential intracellular consequences of the demonstrated salt linkages to stability and lipid binding in ALBP.

  2. Effect of tetrahydrocurcumin on lipid peroxidation and lipids in streptozotocin-nicotinamide-induced diabetic rats.

    Science.gov (United States)

    Murugan, Pidaran; Pari, Leelavinothan

    2006-08-01

    Hyperlipidaemia is an associated complication of diabetes mellitus. We recently reported that tetrahydrocurcumin lowered the blood glucose in diabetic rats. In the present study, we have investigated the effect of tetrahydrocurcumin, one of the active metabolites of curcumin on lipid profile and lipid peroxidation in streptozotocin-nicotinamide-induced diabetic rats. Tetrahydrocurcumin 80 mg/kg body weight was administered orally to diabetic rats for 45 days, resulted a significant reduction in blood glucose and significant increase in plasma insulin in diabetic rats, which proved its antidiabetic effect. Tetrahydrocurcumin also caused a significant reduction in lipid peroxidation (thiobarbituric acid reactive substances and hydroperoxides) and lipids (cholesterol, triglycerides, free fatty acids and phospholipids) in serum and tissues, suggesting its role in protection against lipid peroxidation and its antihyperlipidemic effect. Tetrahydrocurcumin showed a better effect when compared with curcumin. Results of the present study indicate that tetrahydrocurcumin showed antihyperlipidaemic effect in addition to its antidiabetic effect in type 2 diabetic rats.

  3. Lipid Cell Biology: A Focus on Lipids in Cell Division.

    Science.gov (United States)

    Storck, Elisabeth M; Özbalci, Cagakan; Eggert, Ulrike S

    2018-06-20

    Cells depend on hugely diverse lipidomes for many functions. The actions and structural integrity of the plasma membrane and most organelles also critically depend on membranes and their lipid components. Despite the biological importance of lipids, our understanding of lipid engagement, especially the roles of lipid hydrophobic alkyl side chains, in key cellular processes is still developing. Emerging research has begun to dissect the importance of lipids in intricate events such as cell division. This review discusses how these structurally diverse biomolecules are spatially and temporally regulated during cell division, with a focus on cytokinesis. We analyze how lipids facilitate changes in cellular morphology during division and how they participate in key signaling events. We identify which cytokinesis proteins are associated with membranes, suggesting lipid interactions. More broadly, we highlight key unaddressed questions in lipid cell biology and techniques, including mass spectrometry, advanced imaging, and chemical biology, which will help us gain insights into the functional roles of lipids.

  4. Thermodynamic and fluorescence studies of the underlying factors in benzyl alcohol-induced lipid interdigitated phase.

    Science.gov (United States)

    Chen, C H; Hoye, K; Roth, L G

    1996-09-15

    To further investigate factors contributing to the action of alcohol in the solute-induced lipid interdigitation phase, thermodynamic and fluorescence polarization measurements were carried out to study the interaction of benzyl alcohol with dipalmitoyl phosphatidylcholine bilayer vesicles. The obtained results were compared with those previously reported for ethanol and cyclohexanol (L. G. Roth and C-H. Chen, Arch. Biochem. Biophys. 296, 207, 1992). Similar to ethanol, benzyl alcohol was found to exhibit a biphasic effect on the enthalpy (delta Hm) and the temperature (tm) of the lipid-phase transition and the steady-state fluorescence polarization (P) monitored by 1,6-diphenyl-1,3,5-hexatriene. At a total concentration of benzyl alcohol delta Hm and P, which were correlated with the formation of a lipid interdigitated phase, as evidenced by reported X-ray diffraction data. Combining the results with benzyl alcohol and ethanol suggested that simultaneously large changes in delta Hm and P can be used as an indication of the occurrence of a solute-induced lipid interdigitated phase. The overall interacting force in the formation of this lipid phase, as derived from the interactions of the hydroxyl portion of an alcohol with the lipid phosphate head group and the hydrophobic portion of an alcohol with the lipid hydrocarbon chains, may or may not be dominated by hydrophobic interaction. Although lipid/water partition coefficients and the contribution of hydrophobic interaction to the overall interacting force were comparable between benzyl alcohol and cyclohexanol, benzyl alcohol induced lipid interdigitated phase, but not for cyclohexanol. This was due to the ability of benzyl alcohol to be more effective than cyclohexanol in simultaneously interacting with the phosphate head group and the hydrocarbon chains of lipid.

  5. [Chronic low-grade inflammation, lipid risk factors and mortality in functionally dependent elderly].

    Science.gov (United States)

    Vasović, Olga; Trifunović, Danijela; Despotovié, Nebojsa; Milosević, Dragoslav P

    2010-07-01

    It has been proved that a highly sensitive C-reactive protein (hsCRP) can be used as an established marker of chronic inflammation for cardiovascular risk assessment. Since mean values of both low-density cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) decrease during aging, the knowledge that increased hsCRP concentration predicts mortality (Mt) would influence therapy and treatment outcome. The aim of this study was to examine importance of chronic low grade inflammation and its association with lipid risk factors for all-cause Mt in functionally dependent elderly. The participants of this longitudinal prospective study were 257 functionally dependent elderly aged 65-99 years. Baseline measurements: anthropometric measurements, blood pressure, fasting plasma total cholesterol (TC), triglyceride (TG), HDL-C, LDL-C, non-HDL-C, hemoglobin Alc (HbA1c) were recorded and different lipid ratios were calculated. Inflammation was assessed by the levels of white blood cells, fibrinogen and hsCRP. The participants with hsCRP grater than 10 mg/L were excluded from the study. The residual participants (77.4% women) were divided into three groups according to their hsCRP levels: a low (agressive lipid lowering treatment.

  6. Does the commonly used pH-stat method with back titration really quantify the enzymatic digestibility of lipid drug delivery systems? A case study on solid lipid nanoparticles (SLN).

    Science.gov (United States)

    Heider, Martha; Hause, Gerd; Mäder, Karsten

    2016-12-01

    Enzymatic digestion of lipid drug carriers is very important. Commonly, pancreatin induced formation of fatty acids is monitored by the pH-stat method, which provides a fast, but unspecific readout. However, according to the literature, the pKa values of long chain fatty acids are strongly dependent on the local environment and might vary between 4.2 and 10.15. The high pKa values would lead to an incomplete detection of the lipid digestion and false results. In order to investigate these issues in more detail, we produced cetyl palmitate solid lipid nanoparticles (CP-SLN) stabilized with poloxamer 188 or polysorbate 80. The digestion of CP-SLN was investigated by two different and independent readouts. A HPTLC assay was used in addition to the pH-stat method (with or without back titration). An incomplete digestion of CP-SLN was observed with all methods. Partial digestion of polysorbate 80 contributed to the formation of fatty acids. Depending on the investigated system and the experimental conditions (FaSSIF or FeSSIF) the results of both readout methods were comparable or not. For example, in FeSSIF conditions, the values detected by HPTLC were roughly twice as high as the pH-stat results. Our findings on solid lipids agree with data from Helbig et al. on lipid emulsions, where a gas chromatography method detected much higher values than the pH-stat assay (Food Hydrocoll. 28 (2012) 10-19). The results of our pH-stat experiments with back titration at different pH values showed increased values for fatty acids from pH 7.5 to pH 10. The values obtained by back titration at high pH values (pH 9 or higher) did exceed the digestion values measured by HPTLC. Therefore, we conclude that the pH-stat method might give the same results as more specific reference methods, but it might also both under- (without back titration) or overestimate (with back titration) the enzymatic digestion of lipid drug delivery systems. A further outcome of our study was the proof that

  7. Effect of soy protein on serum lipid profile and some lipid ...

    African Journals Online (AJOL)

    The effect of soy protein on serum lipid profile and some lipid metabolizing enzymes in rats fed with cholesterol diets was examined in this study. Rats were subjected to feeding trial over a period of six weeks on formulated diets containing: 20% soy protein with 0% cholesterol (group A), 20% soy protein with 5% cholesterol ...

  8. Exogenous ether lipids predominantly target mitochondria.

    Directory of Open Access Journals (Sweden)

    Lars Kuerschner

    Full Text Available Ether lipids are ubiquitous constituents of cellular membranes with no discrete cell biological function assigned yet. Using fluorescent polyene-ether lipids we analyzed their intracellular distribution in living cells by microscopy. Mitochondria and the endoplasmic reticulum accumulated high amounts of ether-phosphatidylcholine and ether-phosphatidylethanolamine. Both lipids were specifically labeled using the corresponding lyso-ether lipids, which we established as supreme precursors for lipid tagging. Polyfosine, a fluorescent analogue of the anti-neoplastic ether lipid edelfosine, accumulated to mitochondria and induced morphological changes and cellular apoptosis. These data indicate that edelfosine could exert its pro-apoptotic power by targeting and damaging mitochondria and thereby inducing cellular apoptosis. In general, this study implies an important role of mitochondria in ether lipid metabolism and intracellular ether lipid trafficking.

  9. Augmented simvastatin cytotoxicity using optimized lipid nanocapsules: a potential for breast cancer treatment.

    Science.gov (United States)

    Safwat, Sally; Hathout, Rania M; Ishak, Rania A; Mortada, Nahed D

    2017-03-01

    We noticed paucity in exploiting solutol-based lipid nanocapsules in statins formulations though they carry all favorable properties that are needed for cancer passive targeting such as their small particle size, stealth properties, ability to highly accommodate lipophilic drugs, good internalization and P-gp pump inhibition. The aim of this study was to design and optimize new simvastatin drug delivery systems; lipid nanocapsules intended for administration through the intravenous route as potential treatment for breast cancer. Optimized nanocapsules were prepared by the phase-inversion method according to a D-optimal mixture design, characterized and assessed for their cytotoxicity. Three successful models for particle size, polydispersity index (PDI) and percentage of drug released after 48 h were generated. The prepared lipid nanocapsules acquired spherical and homogenous morphology, good stability and tolerance to sterilization. The obtained release profiles demonstrated desired sustained release pattern. Furthermore, testing selected formulations on human breast cancer adenocarcinoma cells showed augmented cytotoxicity of simvastatin reaching low IC50 values as 1.4 ± 0.02 μg/ml compared to the pure drug. The proposed lipid nanocapsules pose promising candidates as simvastatin carriers intended for the targeting of breast cancer.

  10. Nanocellulose size regulates microalgal flocculation and lipid metabolism

    Science.gov (United States)

    Yu, Sun Il; Min, Seul Ki; Shin, Hwa Sung

    2016-01-01

    Harvesting of microalgae is a cost-consuming step for biodiesel production. Cellulose has recently been studied as a biocompatible and inexpensive flocculant for harvesting microalgae via surface modifications such as cation-modifications. In this study, we demonstrated that cellulose nanofibrils (CNF) played a role as a microalgal flocculant via its network geometry without cation modification. Sulfur acid-treated tunicate CNF flocculated microalgae, but cellulose nanocrystals (CNC) did not. In addition, desulfurization did not significantly influence the flocculation efficiency of CNF. This mechanism is likely related to encapsulation of microalgae by nanofibrous structure formation, which is derived from nanofibrils entanglement and intra-hydrogen bonding. Moreover, flocculated microalgae were subject to mechanical stress resulting in changes in metabolism induced by calcium ion influx, leading to upregulated lipid synthesis. CNF do not require surface modifications such as cation modified CNC and flocculation is derived from network geometry related to nanocellulose size; accordingly, CNF is one of the least expensive cellulose-based flocculants ever identified. If this flocculant is applied to the biodiesel process, it could decrease the cost of harvest, which is one of the most expensive steps, while increasing lipid production. PMID:27796311

  11. Prospective Study of Nut Consumption and Incidence of Metabolic Syndrome: Tehran Lipid and Glucose Study.

    Science.gov (United States)

    Hosseinpour-Niazi, Somayeh; Hosseini, Shabnam; Mirmiran, Parvin; Azizi, Fereidoun

    2017-09-23

    This study aimed to assess the association of various types of nut per se, and total nut consumption with the incidence of metabolic syndrome (MetS). A 6.2 ± 0.7-year population-based prospective study was conducted among 1265 adults, aged 19-74 years, participants of the Tehran Lipid and Glucose Study. A 168-item semi-quantitative food frequency questionnaire was used to collect information on nut consumption. MetS was defined according to the Joint Interim Statement guidelines and 276 new cases of MetS were identified. Median ± interquartile range of nut consumption was 2.08 (0.88-5.68) servings/week. After adjusting for family history of diabetes, age, gender, smoking, physical activity, fasting serum glucose at baseline, serum high density lipoprotein cholesterol (HDL-C) at baseline, energy intake, fiber, macronutrients, cholesterol intake, fruit, vegetables, dairy products and body mass index (BMI), a statistically significant decrease was observed in MetS in the third (≥5 servings/week) tertile of nuts (odds ratio: 0.68, 95% CI: 0.44-0.91, p trend: 0.03) compared with the lowest (≤1 serving/week). Walnut consumption showed a significant, inverse association with MetS risk; associations for other nut varieties were not significant. For each additional serving/week of walnuts consumed, incidence of MetS decreased by 3% (ORs: 0.97 CI: 0.93-0.99), after adjusting for confounding factors. Total nut consumption, especially walnuts, reduces the risk of MetS.

  12. Single-molecule study of full-length NaChBac by planar lipid bilayer recording.

    Directory of Open Access Journals (Sweden)

    Andrew Jo

    Full Text Available Planar lipid bilayer device, alternatively known as BLM, is a powerful tool to study functional properties of conducting membrane proteins such as ion channels and porins. In this work, we used BLM to study the prokaryotic voltage-gated sodium channel (Nav NaChBac in a well-defined membrane environment. Navs are an essential component for the generation and propagation of electric signals in excitable cells. The successes in the biochemical, biophysical and crystallographic studies on prokaryotic Navs in recent years has greatly promoted the understanding of the molecular mechanism that underlies these proteins and their eukaryotic counterparts. In this work, we investigated the single-molecule conductance and ionic selectivity behavior of NaChBac. Purified NaChBac protein was first reconstituted into lipid vesicles, which is subsequently incorporated into planar lipid bilayer by fusion. At single-molecule level, we were able to observe three distinct long-lived conductance sub-states of NaChBac. Change in the membrane potential switches on the channel mainly by increasing its opening probability. In addition, we found that individual NaChBac has similar permeability for Na+, K+, and Ca2+. The single-molecule behavior of the full-length protein is essentially highly stochastic. Our results show that planar lipid bilayer device can be used to study purified ion channels at single-molecule level in an artificial environment, and such studies can reveal new protein properties that are otherwise not observable in in vivo ensemble studies.

  13. An Interlaboratory study of lipid effects on steroid radioimmunoassay

    International Nuclear Information System (INIS)

    Bolelli, G.F.; Franceschetti, F.; Mimmi, P.; Malvano, R.; Pilo, A.; Zucchelli; Rota, G.

    1986-01-01

    The lipid effects on the performances of routine steroid radioimmunoassay (RIA) have been assessed using the scheme of the CNR interlaboratory quality control program. Cortisol, estradiol, progesterone and testosterone assays have been considered. In the study, ca 80 laboratories were supplied with two sets of control plasma samples with different triglyceride contents (pool N, ca 120 mg/dl; pool L, ca 310 mg/dl), each corresponding to three steroid levels (level 0: charcoaldeprived samples; levels 1 and 2: the same added with increasing steroid amounts). A comparison of the neat results obtained by partecipants for both levels 1 and 2 of N and P panels - after subtraction of the concentrations estimated for level 0 - gave a direct information on lipid effects (triglycerides being assumed as an index of lipemia). In no case the abnormality high triglyceride content proved effective in practical terms, though significant differences were observed for testosterone and progesterone (ca 10% underestimation in pool L) and for estradiol (ca 10% overestimation in pool L)

  14. Insulin-resistance and lipids metabolism in women at menopause

    Directory of Open Access Journals (Sweden)

    Marina Dmitrуina Gresko

    2018-01-01

    Full Text Available The article describes lipid metabolism in women during premenopausal and considered their relationship with the level of insulin sensitivity and abdominal obesity. Examined 20 women aged 46-48 years, with fixed transition to pre-menopause on the bases of menstrual cycle dysfunction or amenorrhea during a year as well as a decrease of visualized follicular reserve according to the results of ultrasonic examination of the organs of the small pelvis, were involved into investigation. Body mass increase with abdominal obese formation and disorders of the lipid metabolism against a background of insulin resistance is observed in women during pre-menopause against a background of sexual hormones deficiency.

  15. Hippocampal lipid differences in Alzheimer's disease: a human brain study using matrix-assisted laser desorption/ionization-imaging mass spectrometry.

    Science.gov (United States)

    Mendis, Lakshini H S; Grey, Angus C; Faull, Richard L M; Curtis, Maurice A

    2016-10-01

    Alzheimer's disease (AD), the leading cause of dementia, is pathologically characterized by β-amyloid plaques and tau tangles. However, there is also evidence of lipid dyshomeostasis-mediated AD pathology. Given the structural diversity of lipids, mass spectrometry is a useful tool for studying lipid changes in AD. Although there have been a few studies investigating lipid changes in the human hippocampus in particular, there are few reports on how lipids change in each hippocampal subfield (e.g., Cornu Ammonis [CA] 1-4, dentate gyrus [DG] etc.). Since each subfield has its own function, we postulated that there could be lipid changes that are unique to each. We used matrix-assisted laser desorption/ionization-imaging mass spectrometry to investigate specific lipid changes in each subfield in AD. Data from the hippocampus region of six age- and gender-matched normal and AD pairs were analyzed with SCiLS lab 2015b software (SCiLS GmbH, Germany; RRID:SCR_014426), using an analysis workflow developed in-house. Hematoxylin, eosin, and luxol fast blue staining were used to precisely delineate each anatomical hippocampal subfield. Putative lipid identities, which were consistent with published data, were assigned using MS/MS. Both positively and negatively charged lipid ion species were abundantly detected in normal and AD tissue. While the distribution pattern of lipids did not change in AD, the abundance of some lipids changed, consistent with trends that have been previously reported. However, our results indicated that the majority of these lipid changes specifically occur in the CA1 region. Additionally, there were many lipid changes that were specific to the DG. Matrix-assisted laser desorption/ionization-imaging mass spectrometry and our analysis workflow provide a novel method to investigate specific lipid changes in hippocampal subfields. Future work will focus on elucidating the role that specific lipid differences in each subfield play in AD pathogenesis.

  16. On the interaction between fluoxetine and lipid membranes: Effect of the lipid composition

    Science.gov (United States)

    Pham, Vy T.; Nguyen, Trinh Q.; Dao, Uyen P. N.; Nguyen, Trang T.

    2018-02-01

    Molecular interaction between the antidepressant fluoxetine and lipid bilayers was investigated in order to provide insights into the drug's incorporation to lipid membranes. In particular, the effects of lipid's unsaturation degree and cholesterol content on the partitioning of fluoxetine into large unilamellar vesicles (LUVs) comprised of unsaturated 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and saturated 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) were evaluated using second derivative spectrophotometry and Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). It was found that fluoxetine partitioned to a greater extent into the liquid-crystalline DOPC LUVs than into the solid-gel DPPC LUVs. The lipid physical state dependence of drug partitioning was verified by increasing the temperature in which the partition coefficient of fluoxetine significantly increased upon the change of the lipid phase from solid-gel to liquid-crystalline. The incorporation of 28 mol% cholesterol into the LUVs exerted a significant influence on the drug partitioning into both DOPC and DPPC LUVs. The ATR-FTIR study revealed that fluoxetine perturbed the conformation of DOPC more strongly than that of DPPC due to the cis-double bonds in the lipid acyl chains. Fluoxetine possibly bound to the carbonyl moiety of the lipids through the hydrogen bonding formation while displaced some water molecules surrounding the PO2- regions of the lipid head groups. Cholesterol, however, could lessen the interaction between fluoxetine and the carbonyl groups of both DOPC and DPPC LUVs. These findings provided a better understanding of the role of lipid structure and cholesterol on the interaction between fluoxetine and lipid membranes, shedding more light into the drug's therapeutic action.

  17. Pharmacogenetics of lipid diseases

    Directory of Open Access Journals (Sweden)

    Ordovas Jose M

    2004-01-01

    Full Text Available Abstract The genetic basis for most of the rare lipid monogenic disorders have been elucidated, but the challenge remains in determining the combination of genes that contribute to the genetic variability in lipid levels in the general population; this has been estimated to be in the range of 40-60 per cent of the total variability. Therefore, the effect of common polymorphisms on lipid phenotypes will be greatly modulated by gene-gene and gene-environment interactions. This approach can also be used to characterise the individuality of the response to lipid-lowering therapies, whether using drugs (pharmacogenetics or dietary interventions (nutrigenetics. In this regard, multiple studies have already described significant interactions between candidate genes for lipid and drug metabolism that modulate therapeutic response--although the outcomes of these studies have been controversial and call for more rigorous experimental design and analytical approaches. Once solid evidence about the predictive value of genetic panels is obtained, risk and therapeutic algorithms can begin to be generated that should provide an accurate measure of genetic predisposition, as well as targeted behavioural modifications or drugs of choice and personalised dosages of these drugs.

  18. Study of Alterations in Lipid Profile After Burn Injury.

    Directory of Open Access Journals (Sweden)

    Dr.Asha Khubchandani

    2017-06-01

    Full Text Available Introduction: After burn injury, changes in lipid profile occur in body. Dyslipidemia after burn injury is one of the important alterations. Objective: To check alterations in lipid profile after burn injury. Materials and Method: It was cross sectional study which was carried out on 250 burns patients of both sex, with an age group of 18-45 years, and varying burns percentage of 20-80% of total body surface area (TBSA. Serum cholesterol, serum LDL, serum HDL and serum triglyceride level were measured on XL-640 fully-auto biochemical analyser. Serum LDL and HDL were measured by Accelerator Selective Detergent Method. Serum cholesterol and triglyceride were measured by Trindor’s method. Results: Results showed decrease in serum cholesterol, serum LDL and serum HDL, while increase in serum triglyceride level in burns patients compared to normal subjects. Conclusion: This study clearly showed the importance of measuring serum cholesterol, TG, LDL and HDL in burn patients and targeting changes that occur in their levels along the burns course, which may have beneficial effect in protection from organ damage, increasing survival rates and improving burn outcome.

  19. Effects of dietary phospholipid level in cobia (Rachycentron canadum) larvae: growth, survival, plasma lipids and enzymes of lipid metabolism.

    Science.gov (United States)

    Niu, J; Liu, Y J; Tian, L X; Mai, K S; Yang, H J; Ye, C X; Zhu, Y

    2008-03-01

    A study was conducted to determine the effects of dietary phospholipid (PL) levels in cobia (Rachycentron canadum) larvae with regard to growth, survival, plasma lipids and enzymes of lipid metabolism. Fish with an average weight of 0.4 g were fed diets containing four levels of PL (0, 20, 40 and 80 g kg(-1)dry matter: purity 97%) for 42 days. Final body weight (FBW), weight gain (WG) and survival ratio were highest in the 8% PL diet group and mortality was highest in PL-free diet group. We examined the activities of lipoprotein lipase (LPL) and hepatic lipase (HL) in liver, lecithin-cholesterolacyltransferase (LCAT) in plasma as well as plasma lipids and lipoprotein. LCAT activity showed a decrease of more than two-fold in PL-supplemented diet groups compared with the PL-free diet group. HL activity was highest in the 8% PL diet group and the other three groups showed no difference. LPL activity was significantly higher in the PL-supplemented diet groups than in the PL-free diet group. The dietary intervention significantly increased plasma phospholipids and total cholesterol (TC) levels, and the higher free cholesterol (FC) level contributed to the TC level. However, the fish fed PL exhibited a significantly decreased plasma triglyceride (TG) level. The lipoprotein fractions were also affected significantly by the PL. The PL-supplemented diet groups had significantly higher high-density lipoprotein (HDL) compared with the PL-free diet group, but showed a marked decrease in very low-density lipoprotein (VLDL). The results suggested that PL could modify plasma lipoprotein metabolism and lipid profile, and that the optimal dietary PL level may well exceed 80 g kg(-1) for cobia larvae according to growth and survival.

  20. Lipid droplet organelle distribution in populations of dividing cells studied by simulation

    International Nuclear Information System (INIS)

    Dalhaimer, Paul

    2013-01-01

    One of the key questions in cell biology is how organelles are passed from parent to daughter cells. To help address this question, I used Brownian dynamics to simulate lipid droplets as model organelles in populations of dividing cells. Lipid droplets are dynamic bodies that can form both de novo and by fission, they can also be depleted. The quantitative interplay among these three events is unknown but would seem crucial for controlling droplet distribution in populations of dividing cells. Surprisingly, of the three main events studied: biogenesis, fission, and depletion, the third played the key role in maintaining droplet organelle number—and to a lesser extent volume—in populations of dividing cells where formation events would have seemed paramount. In the case of lipid droplets, this provides computational evidence that they must be sustained, most likely through contacts with the endoplasmic reticulum. The findings also agree with video microscopy experiments over much shorter timescales where droplet depletion in fission yeast cells was not observed. In general, this work shows that organelle maintenance is invaluable and lack thereof cannot necessarily be compensated for by organelle formation. This study provides a time-accurate, physical-based template for long-term cell division studies. (paper)

  1. Lipid droplet organelle distribution in populations of dividing cells studied by simulation

    Science.gov (United States)

    Dalhaimer, Paul

    2013-06-01

    One of the key questions in cell biology is how organelles are passed from parent to daughter cells. To help address this question, I used Brownian dynamics to simulate lipid droplets as model organelles in populations of dividing cells. Lipid droplets are dynamic bodies that can form both de novo and by fission, they can also be depleted. The quantitative interplay among these three events is unknown but would seem crucial for controlling droplet distribution in populations of dividing cells. Surprisingly, of the three main events studied: biogenesis, fission, and depletion, the third played the key role in maintaining droplet organelle number—and to a lesser extent volume—in populations of dividing cells where formation events would have seemed paramount. In the case of lipid droplets, this provides computational evidence that they must be sustained, most likely through contacts with the endoplasmic reticulum. The findings also agree with video microscopy experiments over much shorter timescales where droplet depletion in fission yeast cells was not observed. In general, this work shows that organelle maintenance is invaluable and lack thereof cannot necessarily be compensated for by organelle formation. This study provides a time-accurate, physical-based template for long-term cell division studies.

  2. Texture of lipid bilayer domains

    DEFF Research Database (Denmark)

    Jensen, Uffe Bernchou; Brewer, Jonathan R.; Midtiby, Henrik Skov

    2009-01-01

    We investigate the texture of gel (g) domains in binary lipid membranes composed of the phospholipids DPPC and DOPC. Lateral organization of lipid bilayer membranes is a topic of fundamental and biological importance. Whereas questions related to size and composition of fluid membrane domain...... are well studied, the possibility of texture in gel domains has so far not been examined. When using polarized light for two-photon excitation of the fluorescent lipid probe Laurdan, the emission intensity is highly sensitive to the angle between the polarization and the tilt orientation of lipid acyl...... chains. By imaging the intensity variations as a function of the polarization angle, we map the lateral variations of the lipid tilt within domains. Results reveal that gel domains are composed of subdomains with different lipid tilt directions. We have applied a Fourier decomposition method...

  3. Studies on lipid peroxidation and anti-LPO chemicals

    International Nuclear Information System (INIS)

    Wang Chongdao; Qiang Yizhong; Lao Qinhua

    1995-02-01

    The contents of lipid peroxides (LPO) in sera and tissues were determined by the modified spectrophotometry of TBA, and the effects of three chemicals on lipid peroxidation induced by radiation were observed. The items studied included: (1) the normal values of LPO of sera in rats and adults: (2) the normal values in some tissues of rats; (3) the changes of LPO levels of sera in patients with some mental diseases and patients with malignant tumours before and after local gamma irradiation exposure; (4) the changes of LPO contents of some tissues in rats after whole-body gamma irradiation exposure; (5) the changes of LPO contents of some tissues in mice after internal exposure by Th(NO 3 ) 4 solution; (6) the effects of chinonin, tannic acid and squalene on lipid peroxidation induced by irradiation. The results were as follows: (1) the LPO contents in patients with some mental diseases dramatically increased; (2) there was marked difference between the LPO levels before and after local gamma irradiation exposure in patients with malignant tumours; (3) the LPO contents in some tissues of rats remarkably increased after whole-body gamma irradiation exposure; (4) the LPO contents in some tissues of mice dramatically increased and their protein contents markedly reduced after internal exposure, showing a negative correlation between them; (5) a gradual increase in LPO contents in some tissues of mice appeared with increasing dosage of whole-body gamma irradiation exposure at dose range from 0 to 4 Gy. A linear relationship between the dose and the LPO contents was observed; (6) all three chemicals could reduce the LPO levels in liver, spleen and kidney of the irradiated mice. The efficacy of chinonin was better than that of tannic acid and squalene. (5 tabs., 1 fig.)

  4. Role of Neutral Lipids in Tear Fluid Lipid Layer: Coarse-Grained Simulation Study

    DEFF Research Database (Denmark)

    Telenius, J.; Koivuniemi, A.; Kulovesi, P.

    2012-01-01

    Tear fluid lipid layer (TFLL) residing at the air-water interface of tears has been recognized to play an important role in the development of dry eye syndrome. Yet, the composition, structure, and mechanical properties of TFLL are only partly known. Here, we report results of coarse...

  5. Thermal conductivity and rectification in asymmetric archaeal lipid membranes

    Science.gov (United States)

    Youssefian, Sina; Rahbar, Nima; Van Dessel, Steven

    2018-05-01

    Nature employs lipids to construct nanostructured membranes that self-assemble in an aqueous environment to separate the cell interior from the exterior environment. Membrane composition changes among species and according to environmental conditions, which allows organisms to occupy a wide variety of different habitats. Lipid bilayers are phase-change materials that exhibit strong thermotropic and lyotropic phase behavior in an aqueous environment, which may also cause thermal rectification. Among different types of lipids, archaeal lipids are of great interest due to their ability to withstand extreme conditions. In this paper, nonequilibrium molecular dynamics simulations were employed to study the nanostructures and thermal properties of different archaeols and to investigate thermal rectification effects in asymmetric archaeal membranes. In particular, we are interested in understanding the role of bridged phytanyl chains and cyclopentane groups in controlling the phase transition temperature and heat flow across the membrane. Our results indicate that the bridged phytanyl chains decrease the molecular packing of lipids, whereas the existence of cyclopentane rings on the tail groups increases the molecular packing by enhancing the interactions between isoprenoid chains. We found that macrocyclic archaeols have the highest thermal conductivity, whereas macrocyclic archaeols with two cyclopentane rings have the lowest. The effect of the temperature on the variation of thermal conductivity was found to be progressive. Our results further indicate that small thermal rectification effects occur in asymmetric archaeol bilayer membranes at around 25 K temperature gradient. The calculated thermal rectification factor was around 0.09 which is in the range of rectification factor obtained experimentally for nanostructures such as carbon nanotubes (0.07). Such phenomena may be of biological significance and could also be optimized for use in various engineering

  6. Lipidomic and proteomic analysis of Caenorhabditis elegans lipid droplets and identification of ACS-4 as a lipid droplet-associated protein

    Energy Technology Data Exchange (ETDEWEB)

    Vrablik, Tracy L. [Washington State Univ., Pullman, WA (United States); Petyuk, Vladislav A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Larson, Emily M. [Washington State Univ., Pullman, WA (United States); Smith, Richard D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Watts, Jennifer [Washington State Univ., Pullman, WA (United States)

    2015-06-27

    Lipid droplets are cytoplasmic organelles that store neutral lipids for membrane synthesis and energy reserves. In this study, we characterized the lipid and protein composition of purified C. elegans lipid droplets. These lipid droplets are composed mainly of triacylglycerols, surrounded by a phospholipid monolayer composed primarily of phosphatidylcholine and phosphatidylethanolamine. The fatty acid composition of the triacylglycerols was rich in fatty acid species obtained from the dietary E. coli, including cyclopropane fatty acids and cis-vaccenic acid. Unlike other organisms, C. elegans lipid droplets contain very little cholesterol or cholesterol esters. Comparison of the lipid droplet proteomes of wild type and high-fat daf-2 mutant strains shows a relative decrease of MDT-28 abundance in lipid droplets isolated from daf-2 mutants. Functional analysis of lipid droplet proteins identified in our proteomic studies indicated an enrichment of proteins required for growth and fat homeostasis in C. elegans.

  7. Low trans structured fat from flaxseed oil improves plasma and hepatic lipid metabolism in apo E(-/-) mice.

    Science.gov (United States)

    Cho, Yun-Young; Kwon, Eun-Young; Kim, Hye-Jin; Park, Yong-Bok; Lee, Ki-Teak; Park, Taesun; Choi, Myung-Sook

    2009-07-01

    The objective of this study was to explicate the effects of feeding low trans structured fat from flaxseed oil (LF) on plasma and hepatic lipid metabolism involved in apo E(-/-) mice. The animals were fed a commercial shortening (CS), commercial low trans fat (CL) and LF diet based on AIN-76 diet (10% fat) for 12 weeks. LF supplementation exerted a significant suppression in hepatic lipid accumulation with the concomitant decrease in liver weight. The LF significantly lowered plasma total cholesterol and free fatty acid whereas it significantly increased HDL-C concentration and the HDL-C/total-C ratio compared to the CS group. Reduction of hepatic lipid levels in the LF group was related with the suppression of hepatic enzyme activities for fatty acid and triglyceride synthesis, and cholesterol regulating enzyme activity compared to the CS and CL groups. Accordingly, low trans structured fat from flaxseed oil is highly effective for improving hyperlipidemia and hepatic lipid accumulation in apo E(-/-) mice.

  8. Solution or suspension - Does it matter for lipid based systems? In vivo studies of chase dosing lipid vehicles with aqueous suspensions of a poorly soluble drug.

    Science.gov (United States)

    Larsen, A T; Holm, R; Müllertz, A

    2017-08-01

    In this study, the potential of co-administering an aqueous suspension with a placebo lipid vehicle, i.e. chase dosing, was investigated in rats relative to the aqueous suspension alone or a solution of the drug in the lipid vehicle. The lipid investigated in the present study was Labrafil M2125CS and three evaluated poorly soluble model compounds, danazol, cinnarizine and halofantrine. For cinnarizine and danazol the oral bioavailability in rats after chase dosing or dosing the compound dissolved in Labrafil M21515CS was similar and significantly higher than for the aqueous suspension. For halofantrine the chase dosed group had a tendency towards a low bioavailability relative to the Labrafil M2125CS solution, but still a significant higher bioavailability relative to the aqueous suspension. This could be due to factors such as a slower dissolution rate in the intestinal phase of halofantrine or a lower solubility in the colloidal structures formed during digestion, but other mechanisms may also be involved. The study thereby supported the potential of chase dosing as a potential dosing regimen in situations where it is beneficial to have a drug in the solid state, e.g. due to chemical stability issues in the lipid vehicle. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Analysis of lipid profile in lipid storage myopathy.

    Science.gov (United States)

    Aguennouz, M'hammed; Beccaria, Marco; Purcaro, Giorgia; Oteri, Marianna; Micalizzi, Giuseppe; Musumesci, Olimpia; Ciranni, Annmaria; Di Giorgio, Rosa Maria; Toscano, Antonio; Dugo, Paola; Mondello, Luigi

    2016-09-01

    Lipid dysmetabolism disease is a condition in which lipids are stored abnormally in organs and tissues throughout the body, causing muscle weakness (myopathy). Usually, the diagnosis of this disease and its characterization goes through dosage of Acyl CoA in plasma accompanied with evidence of droplets of intra-fibrils lipids in the patient muscle biopsy. However, to understand the pathophysiological mechanisms of lipid storage diseases, it is useful to identify the nature of lipids deposited in muscle fiber. In this work fatty acids and triglycerides profile of lipid accumulated in the muscle of people suffering from myopathies syndromes was characterized. In particular, the analyses were carried out on the muscle biopsy of people afflicted by lipid storage myopathy, such as multiple acyl-coenzyme A dehydrogenase deficiency, and neutral lipid storage disease with myopathy, and by the intramitochondrial lipid storage dysfunctions, such as deficiencies of carnitine palmitoyltransferase II enzyme. A single step extraction and derivatization procedure was applied to analyze fatty acids from muscle tissues by gas chromatography with a flame ionization detector and with an electronic impact mass spectrometer. Triglycerides, extracted by using n-hexane, were analyzed by high performance liquid chromatography coupled to mass spectrometer equipped with an atmospheric pressure chemical ionization interface. The most representative fatty acids in all samples were: C16:0 in the 13-24% range, C18:1n9 in the 20-52% range, and C18:2n6 in the 10-25% range. These fatty acids were part of the most representative triglycerides in all samples. The data obtained was statistically elaborated performing a principal component analysis. A satisfactory discrimination was obtained among the different diseases. Using component 1 vs component 3 a 43.3% of total variance was explained. Such results suggest the important role that lipid profile characterization can have in supporting a correct

  10. Involvement of lipid-protein complexes in plant-microorganism interactions

    Directory of Open Access Journals (Sweden)

    Blein Jean-Pierre

    2002-01-01

    Full Text Available Increasing concerns about the environmental impact of modern agricultural have prompted research for alternate practices to pesticide treatments, notably using plant defense mechanisms. Thus, isolation and characterization of plant defense elicitors have been the main step of studies in many groups. Moreover, in the global concept of interactions between organisms and their environment, a major concern is to discriminate recognition between exogenous and endogenous signals, notably during pathogenic or allergenic interactions involving small proteins, such as elicitins or lipid transfer proteins (LTPs. Elicitins and lipid transfer proteins (LTP are both able to load and transfer lipidic molecules and share some structural and functional properties. While elicitins are known as elicitors of plant defense mechanisms, the biological function of LTPs is still an enigma. They are ubiquitous plant proteins able to load and transfer hydrophobic molecules such as fatty acids or phospholipids. Among them, LTPs1 (type 1 lipid transfer proteins constitute a multigenic family of secreted plant lipid binding proteins that are constitutively expressed in specific tissues and/or induced in response to biotic and abiotic stress (for reviews [1-4]. Their biological function is still unknown, even if some data provide arguments for a role of these proteins in the assembly of extracellular hydrophobic polymers (i.e., cutin and suberin [2, 4] and/or in plant defense against fungal pathogens [1, 3]. Beside their involvement in plant defense, LTPs1 are also known to be pan-allergens of plant-derived foods [5]. Finally, the discovery of the sterol carrier-properties of elicitins has opened new perspectives dealing with the relationship between this function and the elicitor activity of these small cystein-rich proteins. Nevertheless, this elicitor activity is restrained to few plant species, and thus does not appear in accordance with a universal lipid transfer

  11. [STUDY OF LIPIDS SEED'S OIL OF VITEX AGNUS CASTUS GROWING IN GEORGIA].

    Science.gov (United States)

    Kikalishvili, B; Zurabashvili, D; Sulakvelidze, Ts; Malania, M; Turabelidze, D

    2016-07-01

    There was established the lipid composition of the seeds of Vitex agnus castus L. by the qualitative and quantitative methods of analyses. There were received neutral lipids from the seeds by extraction with hexane in the yield 10%, counted on dry material. For the divide of neutral lipids there was used silica gel plates LS 5/40 in the systems of solvents: 1. petroleum ether-diethylether-acidum aceticum (85:14:1), 2. hexane-diethylether (1:1). After obtaining neutral lipids from the residual plant shrot pollar lipids was extracted with the mixture of chloroform-methanol (2:1) and was divided on silica gel plates LS 5/40, mobile phase: 1. chloroform-methanol-25% ammonium hydrate 2. chloroform-methanol icy acetic acid-water (170:25:25:6). In the sum of polar lipids qualitatively were established phospholipids: lisophosphatidylcholine, phosphatidylinosit, phospatidylethanolamine and N-acylphosphatidylethanolamine, in neutral lipids, hydrocarbons, triglycerids, free fatty acids and sterines. By the method of high performance liquid chromatography analyses there were identified following free fatty acids: lauric, myristic, palmitic, stearic, linolic, linolenic, arachidic and begenic, unsaturated oleic and polyunsaturated linolic and linolenic acids. obtained oil with unique composition from the seeds of Vitex agnus-castus indicates to its high biological activity and importance for usage in medicine.

  12. Diffusion studies on permeable nitroxyl spin probe through lipid bilayer membrane

    International Nuclear Information System (INIS)

    Benial, A. Milton Franklin; Meenakumari, V.; Ichikawa, Kazuhiro; Yamada, Ken-ichi; Utsumi, Hideo; Hyodo, Fuminori; Jawahar, A.

    2014-01-01

    Electron spin resonance (ESR) studies were carried out for 2mM 14 N labeled deutrated permeable 3- methoxycarbonyl-2,2,5,5-tetramethyl-pyrrolidine-1-oxyl (MC-PROXYL) in pure water, 1 mM, 2 mM, 3 mM and 4 mM concentration of MC-PROXYL in 300 mM concentration of liposomal solution by using a L-band ESR spectrometer. The ESR parameters such as linewidth, hyperfine coupling constant, g-factor, partition parameter and permeability were reported. The partition parameter and permeability values indicate the maximum spin distribution in the lipid phase at 2 mM concentration. This study illustrates that ESR can be used to differentiate between the intra and extra-membrane water by loading the liposome vesicles with a lipid-permeable nitroxyl spin probe. From the ESR results, the radical concentration was optimized as 2 mM in liposomal solution for ESR phantom studies and experiments

  13. Study on the effects of consumption of milk containing Lactobacillus acidophilus on serum lipid trends and weight gain of rats fed high lipid diet

    Directory of Open Access Journals (Sweden)

    H Mirzaei

    2008-02-01

    Full Text Available Despite the significant progresses made in the reduction of mortality due to cardiovascular diseases, they are still the primary cause of death in many countries and hyperlipidemia is an important causal agent of cardiovascular diseases. Probiotics are food supplements containing live microbes which balance the flora of the digestive system and produce positive effects in the host body. L.acidophilus is a beneficial bacterium used in the production of probiotic products .The aim of this study is to evaluate the effects of consumption of milk containing L.acidophilus on serum lipid trends of rats fed high lipid diet. This is an experimental study in which 30 male albino Wistar rats with a body weight of 200±15 gr. were randomly allocated to two groups of treatment and control each containing 15 rats which were adapted to a high lipid diet (11.74% and water containing 25% milk within a week. Rats in both groups received high lipid diet and water containing 25% milk for 60 days with the exception that rats in the treatment group received water containing L. acidophilus at a level of 109 CFU/rat/day throughout the experiment. Independent t-test revealed that at a level of α= 0.05, mean levels of total cholesterol and LDL-C of rats in the treatment group was significantly lower than the control group (p

  14. Application of Proteomics and Lipid Studies in Environmental Biotechnology

    OpenAIRE

    Mukhopadhyay, Aindrila

    2008-01-01

    The overview of changes in protein levels or states in response to a growth condition, stress, mutation or metabolic engineering is invaluable in understanding the physiology of a microbial system. The lipid profile of the cell is similarly a valuable diagnostic of the cellular response and health, especially in context of survival in a fluctuating environment. To obtain comprehensive cellular models, post-transcriptional cell wide surveys at the levels of proteins and lipids are required. Bo...

  15. Effects of flaxseed consumption on systemic inflammation and serum lipid profile in hemodialysis patients with lipid abnormalities.

    Science.gov (United States)

    Khalatbari Soltani, Saman; Jamaluddin, Rosita; Tabibi, Hadi; Mohd Yusof, Barakatun Nisak; Atabak, Shahnaz; Loh, Su-Peng; Rahmani, Leila

    2013-04-01

    Inflammation and lipid abnormalities are two important risk factors for cardiovascular disease in hemodialysis (HD) patients. The present study was designed to investigate the effects of flaxseed consumption on systemic inflammation and serum lipid profile in HD patients with lipid abnormalities. This was an unblinded, randomized clinical trial. Thirty HD patients with dyslipidemia (triglyceride >200 mg/dL and/or high-density lipoprotein-cholesterol (HDL-C) consumption improves lipid abnormalities and reduces systemic inflammation in HD patients with lipid abnormalities. © 2012 The Authors. Hemodialysis International © 2012 International Society for Hemodialysis.

  16. PENGEMBANGAN SISTEM NANOSTRUCTURED LIPID CARRIERS (NLC) MELOXICAM DENGAN LIPID MONOSTEARIN DAN MIGLYOL 808 MENGGUNAKAN METODE EMULSIFIKASI

    OpenAIRE

    Rahmi Annisa; Esti Hendradi; Dewi Melani

    2016-01-01

    The aim this study was to determine the effect of Monostearin and Miglyol 808 lipid ratio in NLC system formulation resulting in physicochemical characteristics, release rate, and penetration rate. The NLC making was done by using emulsification method. In the formulation of NLC meloxicam, 3 different lipid ratios were used, including ratios of 6:4, 7:3, 8:2.  Meloxicam served as active ingredient, monostearin served as solid lipid, miglyol 808 served as a liquid lipid, and tween 80 was surfa...

  17. Polymorphism of lipid self-assembly systems

    International Nuclear Information System (INIS)

    Takahashi, Hiroshi

    2002-01-01

    When lipid molecules are dispersed into an aqueous medium, various self-organized structures are formed, depending on conditions (temperature, concentration, etc), in consequence of the amphipathic nature of the molecules. In addition, lipid self-assembly systems exhibit polymorphic phase transition behavior. Since lipids are one of main components of biomembranes, studies on the structure and thermodynamic properties of lipid self-assembly systems are fundamentally important for the consideration of the stability of biomembranes. (author)

  18. Lipid alterations in lipid rafts from Alzheimer's disease human brain cortex.

    Science.gov (United States)

    Martín, Virginia; Fabelo, Noemí; Santpere, Gabriel; Puig, Berta; Marín, Raquel; Ferrer, Isidre; Díaz, Mario

    2010-01-01

    Lipid rafts are membrane microdomains intimately associated with cell signaling. These biochemical microstructures are characterized by their high contents of sphingolipids, cholesterol and saturated fatty acids and a reduced content of polyunsaturated fatty acids (PUFA). Here, we have purified lipid rafts of human frontal brain cortex from normal and Alzheimer's disease (AD) and characterized their biochemical lipid composition. The results revealed that lipid rafts from AD brains exhibit aberrant lipid profiles compared to healthy brains. In particular, lipid rafts from AD brains displayed abnormally low levels of n-3 long chain polyunsaturated fatty acids (LCPUFA, mainly 22:6n-3, docosahexaenoic acid) and monoenes (mainly 18:1n-9, oleic acid), as well as reduced unsaturation and peroxidability indexes. Also, multiple relationships between phospholipids and fatty acids were altered in AD lipid rafts. Importantly, no changes were observed in the mole percentage of lipid classes and fatty acids in rafts from normal brains throughout the lifespan (24-85 years). These indications point to the existence of homeostatic mechanisms preserving lipid raft status in normal frontal cortex. The disruption of such mechanisms in AD brains leads to a considerable increase in lipid raft order and viscosity, which may explain the alterations in lipid raft signaling observed in AD.

  19. Lipid Profile in Sudanese Diabetic Patients

    International Nuclear Information System (INIS)

    Naway, L. M. Y.

    2011-04-01

    This study composes of two parts, the first one is an experiment to evaluate the level of blood glucose and lipid profile (TC, TG, LDL, HDL and VLDL) among diabetic patients and comparison of the result with non diabetic subjects and the second one is a survey to assess the standards of health care and patients knowledge. The subject were divided into two groups according to insulin requirement. Type 1 is insulin dependent diabetes mellitus and type 2 is non insulin dependent diabetes mellitus and then divided according to gender (males and female) subgroups. The study subjects selected for this study consist of one hundred Sudanese diabetic patients from Ribat University Hospital during January 2009 they had mean age (52±11.063) years,a mean height (165.82±8.573) cm and a mean weight of (70.20±11.203) kg. fifty healthy non diabetic subject were chosen as controls, their mean age (45.72±11.169) years, mean height (167.28±9.450) cm and mean weight (71.02±13.429) kg. Blood glucose and lipid profile total cholesterol (TC), triglycerides (TG), low density lipoprotein (LDL) and high density lipoprotein (HDL) were measured by enzymatic colorimetric methods in both groups, and very low density lipoprotein cholesterol were calculated for each sample. All patients were interviewed and filled out the questionnaire consisted of five parts. The result of the study found highly significant elevated level of blood glucose level among diabetic patients compared to non diabetic subjects. In addition to significant elevated level of serum lipids TC p=0.001, TG p=0.001, LDL p=0.001, and VLDL p=0.001. And decrease in HDL P=0.001 level in diabetic patient compared to non diabetic subjects. Among subgroups (type 1, type 2) diabetic patients glucose level and serum total cholesterol, triglycerides, LDL cholesterol and VLDL cholestrol were significantly higher (p<0.5) while HDL cholestrol was significantly lower when compared to non diabetic subjects. Non statistically variation

  20. Lipid and carotenoid cooperation-driven adaptation to light and temperature stress in Synechocystis sp. PCC6803.

    Science.gov (United States)

    Zakar, Tomas; Herman, Eva; Vajravel, Sindhujaa; Kovacs, Laszlo; Knoppová, Jana; Komenda, Josef; Domonkos, Ildiko; Kis, Mihaly; Gombos, Zoltan; Laczko-Dobos, Hajnalka

    2017-05-01

    Polyunsaturated lipids are important components of photosynthetic membranes. Xanthophylls are the main photoprotective agents, can assist in protection against light stress, and are crucial in the recovery from photoinhibition. We generated the xanthophyll- and polyunsaturated lipid-deficient ROAD mutant of Synechocystis sp. PCC6803 (Synechocystis) in order to study the little-known cooperative effects of lipids and carotenoids (Cars). Electron microscopic investigations confirmed that in the absence of xanthophylls the S-layer of the cellular envelope is missing. In wild-type (WT) cells, as well as the xanthophyll-less (RO), polyunsaturated lipid-less (AD), and the newly constructed ROAD mutants the lipid and Car compositions were determined by MS and HPLC, respectively. We found that, relative to the WT, the lipid composition of the mutants was remodeled and the Car content changed accordingly. In the mutants the ratio of non-bilayer-forming (NBL) to bilayer-forming (BL) lipids was found considerably lower. Xanthophyll to β-carotene ratio increased in the AD mutant. In vitro and in vivo methods demonstrated that saturated, monounsaturated lipids and xanthophylls may stabilize the trimerization of Photosystem I (PSI). Fluorescence induction and oxygen-evolving activity measurements revealed increased light sensitivity of RO cells compared to those of the WT. ROAD showed a robust increase in light susceptibility and reduced recovery capability, especially at moderate low (ML) and moderate high (MH) temperatures, indicating a cooperative effect of xanthophylls and polyunsaturated lipids. We suggest that both lipid unsaturation and xanthophylls are required for providing the proper structure and functioning of the membrane environment that protects against light and temperature stress. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Integrative Analysis of Subcellular Quantitative Proteomics Studies Reveals Functional Cytoskeleton Membrane-Lipid Raft Interactions in Cancer.

    Science.gov (United States)

    Shah, Anup D; Inder, Kerry L; Shah, Alok K; Cristino, Alexandre S; McKie, Arthur B; Gabra, Hani; Davis, Melissa J; Hill, Michelle M

    2016-10-07

    Lipid rafts are dynamic membrane microdomains that orchestrate molecular interactions and are implicated in cancer development. To understand the functions of lipid rafts in cancer, we performed an integrated analysis of quantitative lipid raft proteomics data sets modeling progression in breast cancer, melanoma, and renal cell carcinoma. This analysis revealed that cancer development is associated with increased membrane raft-cytoskeleton interactions, with ∼40% of elevated lipid raft proteins being cytoskeletal components. Previous studies suggest a potential functional role for the raft-cytoskeleton in the action of the putative tumor suppressors PTRF/Cavin-1 and Merlin. To extend the observation, we examined lipid raft proteome modulation by an unrelated tumor suppressor opioid binding protein cell-adhesion molecule (OPCML) in ovarian cancer SKOV3 cells. In agreement with the other model systems, quantitative proteomics revealed that 39% of OPCML-depleted lipid raft proteins are cytoskeletal components, with microfilaments and intermediate filaments specifically down-regulated. Furthermore, protein-protein interaction network and simulation analysis showed significantly higher interactions among cancer raft proteins compared with general human raft proteins. Collectively, these results suggest increased cytoskeleton-mediated stabilization of lipid raft domains with greater molecular interactions as a common, functional, and reversible feature of cancer cells.

  2. Stratum Corneum Barrier Lipids in Cholesteatoma

    DEFF Research Database (Denmark)

    Svane-Knudsen, V; Halkier-Sørensen, L; Rasmussen, G

    2000-01-01

    emerged. When the corneocyte reaches the transitional stage to the stratum corneum, the Odland bodies accumulate near the cell membrane and discharge their contents of lipid and enzymes. The lipids are reorganized into multiple long sheets of lamellar structures that embrace the keratinized corneocytes......, as seen in the formation and maintenance of the cutaneous permeability barrier. In this study we draw the attention to the facts that the cholesteatoma epithelium is capable of producing not only cholesterol, but also several lipids, and that the lipid molecules are organized in multilamellar structures......Specimens from primary cholesteatomas were examined under the electron microscope using a lipid-retaining method that is best suited for intracellular lipids and a method that is best for intercellular lipids. In the stratum granulosum of the squamous epithelium, a large number of Odland bodies...

  3. Cannabinoid antagonist in nanostructured lipid carriers (NLCs): design, characterization and in vivo study

    Energy Technology Data Exchange (ETDEWEB)

    Esposito, Elisabetta; Ravani, Laura [Department of Life Sciences and Biotechnology, University of Ferrara, I-44121 Ferrara (Italy); Drechsler, Markus [BIMF/Soft Matter Electron Microscopy, University of Bayreuth (Germany); Mariani, Paolo [Department of Life and Environmental Sciences and CNISM, Università Politecnica delle Marche, I-60100 Ancona (Italy); Contado, Catia [Department of Chemical and Pharmaceutical Sciences, University of Ferrara, I-44121 Ferrara (Italy); Ruokolainen, Janne [Department of Applied Physics, Aalto University, 00076 Aalto (Finland); Ratano, Patrizia; Campolongo, Patrizia [Department of Physiology and Pharmacology, Sapienza University of Rome, 00185 Roma (Italy); Trezza, Viviana [Department of Science, Roma Tre University, 00146 Roma (Italy); Nastruzzi, Claudio, E-mail: nas@unife.it [Department of Life Sciences and Biotechnology, University of Ferrara, I-44121 Ferrara (Italy); Cortesi, Rita [Department of Life Sciences and Biotechnology, University of Ferrara, I-44121 Ferrara (Italy)

    2015-03-01

    This study describes the preparation, characterization, and in vivo evaluation in rats of nanostructured lipid carriers (NLCs) encapsulating rimonabant (RMN) as prototypical cannabinoid antagonist. A study was conducted in order to optimize NLC production by melt and ultrasonication method. NLCs were prepared by alternatively adding the lipid phase into the aqueous one (direct protocol) or the aqueous phase into the lipid one (reverse protocol). RMN-NLCs have been characterized by cryogenic transmission electron microscopy (cryo-TEM), X-ray, photon correlation spectroscopy (PCS) and sedimentation field flow fractionation (SdFFF). Reverse NLCs were treated with polysorbate 80. RMN release kinetics have been determined in vitro by dialysis method. In vivo RMN biodistribution in rats was evaluated after intranasal (i.n.) administration of reverse RMN-NLC. The reverse protocol enabled to prevent the lost of lipid phase and to achieve higher RMN encapsulation efficacy (EE) with respect to the direct protocol (98% w/w versus 67% w/w). The use of different protocols did not affect NLC morphology and dimensional distribution. An in vitro dissolutive release rate of RMN was calculated. The in vivo data indicate that i.n. administration of RMN by reverse NLC treated with polysorbate 80 increased RMN concentration in the brain with respect to the drug in solution. The nanoencapsulation protocol presented here appears as an optimal strategy to improve the low solubility of cannabinoid compounds in an aqueous system suitable for in vivo administration. - Highlights: • Rimonabant (RMN) can be encapsulated in nanostructured lipid carriers (NLCs). • Nanoencapsulation improves RMN solubility in a stable physiologic aqueous formulation. • RMN is released in vitro from NLC by a controlled dissolutive release modality. • I.n. administration leads to higher RMN concentration in the brain with respect to plasma. • NLC increases RMN concentration in the brain with respect to

  4. Membrane-spanning lipids for an uncompromised monitoring of membrane fusion and intermembrane lipid transfer

    Science.gov (United States)

    Schwarzmann, Günter; Breiden, Bernadette; Sandhoff, Konrad

    2015-01-01

    A Förster resonance energy transfer-based fusion and transfer assay was developed to study, in model membranes, protein-mediated membrane fusion and intermembrane lipid transfer of fluorescent sphingolipid analogs. For this assay, it became necessary to apply labeled reporter molecules that are resistant to spontaneous as well as protein-mediated intermembrane transfer. The novelty of this assay is the use of nonextractable fluorescent membrane-spanning bipolar lipids. Starting from the tetraether lipid caldarchaeol, we synthesized fluorescent analogs with fluorophores at both polar ends. In addition, we synthesized radioactive glycosylated caldarchaeols. These labeled lipids were shown to stretch through bilayer membranes rather than to loop within a single lipid layer of liposomes. More important, the membrane-spanning lipids (MSLs) in contrast to phosphoglycerides proved to be nonextractable by proteins. We could show that the GM2 activator protein (GM2AP) is promiscuous with respect to glycero- and sphingolipid transfer. Saposin (Sap) B also transferred sphingolipids albeit with kinetics different from GM2AP. In addition, we could unambiguously show that the recombinant activator protein Sap C x His6 induced membrane fusion rather than intermembrane lipid transfer. These findings showed that these novel MSLs, in contrast with fluorescent phosphoglycerolipids, are well suited for an uncompromised monitoring of membrane fusion and intermembrane lipid transfer. PMID:26269359

  5. Membrane-spanning lipids for an uncompromised monitoring of membrane fusion and intermembrane lipid transfer.

    Science.gov (United States)

    Schwarzmann, Günter; Breiden, Bernadette; Sandhoff, Konrad

    2015-10-01

    A Förster resonance energy transfer-based fusion and transfer assay was developed to study, in model membranes, protein-mediated membrane fusion and intermembrane lipid transfer of fluorescent sphingolipid analogs. For this assay, it became necessary to apply labeled reporter molecules that are resistant to spontaneous as well as protein-mediated intermembrane transfer. The novelty of this assay is the use of nonextractable fluorescent membrane-spanning bipolar lipids. Starting from the tetraether lipid caldarchaeol, we synthesized fluorescent analogs with fluorophores at both polar ends. In addition, we synthesized radioactive glycosylated caldarchaeols. These labeled lipids were shown to stretch through bilayer membranes rather than to loop within a single lipid layer of liposomes. More important, the membrane-spanning lipids (MSLs) in contrast to phosphoglycerides proved to be nonextractable by proteins. We could show that the GM2 activator protein (GM2AP) is promiscuous with respect to glycero- and sphingolipid transfer. Saposin (Sap) B also transferred sphingolipids albeit with kinetics different from GM2AP. In addition, we could unambiguously show that the recombinant activator protein Sap C x His6 induced membrane fusion rather than intermembrane lipid transfer. These findings showed that these novel MSLs, in contrast with fluorescent phosphoglycerolipids, are well suited for an uncompromised monitoring of membrane fusion and intermembrane lipid transfer. Copyright © 2015 by the American Society for Biochemistry and Molecular Biology, Inc.

  6. Interaction of cholesterol-conjugated ionizable amino lipids with biomembranes: lipid polymorphism, structure-activity relationship, and implications for siRNA delivery.

    Science.gov (United States)

    Zhang, Jingtao; Fan, Haihong; Levorse, Dorothy A; Crocker, Louis S

    2011-08-02

    Delivery of siRNA is a major obstacle to the advancement of RNAi as a novel therapeutic modality. Lipid nanoparticles (LNP) consisting of ionizable amino lipids are being developed as an important delivery platform for siRNAs, and significant efforts are being made to understand the structure-activity relationship (SAR) of the lipids. This article uses a combination of small-angle X-ray scattering (SAXS) and differential scanning calorimetry (DSC) to evaluate the interaction between cholesterol-conjugated ionizable amino lipids and biomembranes, focusing on an important area of lipid SAR--the ability of lipids to destabilize membrane bilayer structures and facilitate endosomal escape. In this study, cholesterol-conjugated amino lipids were found to be effective in increasing the order of biomembranes and also highly effective in inducing phase changes in biological membranes in vitro (i.e., the lamellar to inverted hexagonal phase transition). The phase transition temperatures, determined using SAXS and DSC, serve as an indicator for ranking the potency of lipids to destabilize endosomal membranes. It was found that the bilayer disruption ability of amino lipids depends strongly on the amino lipid concentration in membranes. Amino lipids with systematic variations in headgroups, the extent of ionization, tail length, the degree of unsaturation, and tail asymmetry were evaluated for their bilayer disruption ability to establish SAR. Overall, it was found that the impact of these lipid structure changes on their bilayer disruption ability agrees well with the results from a conceptual molecular "shape" analysis. Implications of the findings from this study for siRNA delivery are discussed. The methods reported here can be used to support the SAR screening of cationic lipids for siRNA delivery, and the information revealed through the study of the interaction between cationic lipids and biomembranes will contribute significantly to the design of more efficient si

  7. The dynamic of lipid oxidation in human myotubes

    DEFF Research Database (Denmark)

    Gaster, Michael

    2009-01-01

    Both endogenous and exogenous lipid levels may be regulators of total lipid oxidation in skeletal muscles. We studied the dynamics of lipid oxidation in human myotubes established from healthy, lean subjects exposed to acutely and chronically increased palmitate concentrations. The intramyocellular...... triacylglycerol content increased with chronic palmitate exposure. Both, ectopically increased intracellular and extracellular lipid levels were simultaneously oxidized and could partly suppress each other's oxidation. Overall, the highest acute palmitate treatments stimulated fatty acid oxidation whilst...... the highest chronic treatments decreased total lipid oxidation. Intracellular lipids showed a more complete oxidation than exogenous lipids. Endogenous lipids reduced insulin-mediated glucose oxidation. Thus, both endogenous and exogenous lipid concentrations regulated each other's oxidation and total lipid...

  8. Defining Lipid Transport Pathways in Animal Cells

    Science.gov (United States)

    Pagano, Richard E.; Sleight, Richard G.

    1985-09-01

    A new technique for studying the metabolism and intracellular transport of lipid molecules in living cells based on the use of fluorescent lipid analogs is described. The cellular processing of various intermediates (phosphatidic acid and ceramide) and end products (phosphatidylcholine and phosphatidylethanolamine) in lipid biosynthesis is reviewed and a working model for compartmentalization during lipid biosynthesis is presented.

  9. Multinuclear NMR studies of single lipid bilayers supported in cylindrical aluminum oxide nanopores.

    Science.gov (United States)

    Gaede, Holly C; Luckett, Keith M; Polozov, Ivan V; Gawrisch, Klaus

    2004-08-31

    Lipid bilayers were deposited inside the 0.2 microm pores of anodic aluminum oxide (AAO) filters by extrusion of multilamellar liposomes and their properties studied by 2H, 31P, and 1H solid-state NMR. Only the first bilayer adhered strongly to the inner surface of the pores. Additional layers were washed out easily by a flow of water as demonstrated by 1H magic angle spinning NMR experiments with addition of Pr3+ ions to shift accessible lipid headgroup resonances. A 13 mm diameter Anopore filter of 60 microm thickness oriented approximately 2.5 x 10(-7) mol of lipid as a single bilayer, corresponding to a total membrane area of about 500 cm2. The 2H NMR spectra of chain deuterated POPC are consistent with adsorption of wavy, tubular bilayers to the inner pore surface. By NMR diffusion experiments, we determined the average length of those lipid tubules to be approximately 0.4 microm. There is evidence for a thick water layer between lipid tubules and the pore surface. The ends of tubules are well sealed against the pore such that Pr3+ ions cannot penetrate into the water underneath the bilayers. We successfully trapped poly(ethylene glycol) (PEG) with a molecular weight of 8000 in this water layer. From the quantity of trapped PEG, we calculated an average water layer thickness of 3 nm. Lipid order parameters and motional properties are unperturbed by the solid support, in agreement with existence of a water layer. Such unperturbed, solid supported membranes are ideal for incorporation of membrane-spanning proteins with large intra- and extracellular domains. The experiments suggest the promise of such porous filters as membrane support in biosensors.

  10. Ageing mechanisms and associated lipid changes.

    Science.gov (United States)

    Kolovou, Genovefa; Katsiki, Niki; Pavlidis, Antonis; Bilianou, Helen; Goumas, George; Mikhailidis, Dimitri P

    2014-01-01

    Ageing is related to slowdown/breakdown of the somatotropic axis (i.e. the somatopause) leading to many physiological changes. The somatopause is accompanied by DNA and other macromolecule damage, and is characterized by a progressive decline in vitality and tissue function. We still do not have a definitive understanding of the mechanism( s) of ageing. Several overlapping theories have been proposed such as: 1) The free radical theory, 2) Mitochondrial Ageing, 3) The Glycation Theory, 4) Protein Damage and Maintenance in Ageing, and, 5) DNA Damage and Repair. Furthermore, several models of ageing were introduced such as genetically programmed senescence, telomere shortening, genomic instability, heterochromatin loss, altered epigenetic patterns and long lived cells. There are certain lipid modifications associated with the somatopause, characterized mainly by an increase in total cholesterol and triglyceride levels in both genders. In this review we consider the mechanisms of ageing and the associated changes in lipid metabolism according to gender.

  11. Supercritical fluid extraction of meat lipids: an alternative approach to the identification of irradiated meats

    International Nuclear Information System (INIS)

    Hampson, J.W.; Jones, K.C.; Foglia, T.A.; Kohout, K.M.

    1996-01-01

    Ionizing radiation is currently under study as an alternative method for extending the shelf life of meats and meat products. Accordingly, methods are needed to determine if a meat or meat product has been exposed to ionizing radiation. In this study, a method is described for the isolation and analysis of volatile hydrocarbons formed in meat lipids after exposure to ionizing radiation. The method is based on supercritical fluid extraction of the hydrocarbons from meat lipids and subsequent identification and quantitation of individual hydrocarbons by gas chromatography (GC) with a mass selection detector (MSD). Supercritical carbon dioxide at 175 bar and 40°C extracted the hydrocarbon fraction from total meat lipids within 20 min. The presence of radiolytic hydrocarbons, as determined by GC/MSD, was then correlated to the degree of irradiation of the meat from 0 to 10 kGy. Besides being faster, this method has the advantage of reduced solvent consumption when compared to current methods for determining if a meat or meat product has been irradiated

  12. Lipid profiling in sewage sludge.

    Science.gov (United States)

    Zhu, Fenfen; Wu, Xuemin; Zhao, Luyao; Liu, Xiaohui; Qi, Juanjuan; Wang, Xueying; Wang, Jiawei

    2017-06-01

    High value-added reutilization of sewage sludge from wastewater treatment plants (WWTPs) is essential in sustainable development in WWTPs. However, despite the advantage of high value reutilization, this process must be based on a detailed study of organics in sludge. We used the methods employed in life sciences to determine the profile of lipids (cellular lipids, free fatty acids (FFAs), and wax/gum) in five sludge samples obtained from three typical WWTPs in Beijing; these samples include one sludge sample from a primary sedimentation tank, two activated sludge samples from two Anaerobic-Anoxic-Oxic (A2/O) tanks, and two activated sludge samples from two membrane bioreactor tanks. The percentage of total raw lipids varied from 2.90% to 12.3%. Sludge from the primary sedimentation tank showed the highest concentrations of lipid, FFA, and wax/gum and the second highest concentration of cellular lipids. All activated sludge contained an abundance of cellular lipids (>54%). Cells in sludge can from plants, animals, microbes and so on in wastewater. Approximately 14 species of cellular lipids were identified, including considerable high value-potential ceramide (9567-38774 mg/kg), coenzyme (937-3897 mg/kg), and some phosphatidylcholine (75-548 mg/kg). The presence of those lipid constituents would thus require a wider range of recovery methods for sludge. Both cellular lipids and FFAs contain an abundance of C16-C18 lipids at high saturation level, and they serve as good resources for biodiesel production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Effect of homocysteine-lowering nutrients on blood lipids: results from four randomised, placebo-controlled studies in healthy humans.

    Directory of Open Access Journals (Sweden)

    Margreet R Olthof

    2005-05-01

    Full Text Available BACKGROUND: Betaine (trimethylglycine lowers plasma homocysteine, a possible risk factor for cardiovascular disease. However, studies in renal patients and in obese individuals who are on a weight-loss diet suggest that betaine supplementation raises blood cholesterol; data in healthy individuals are lacking. Such an effect on cholesterol would counteract any favourable effect on homocysteine. We therefore investigated the effect of betaine, of its precursor choline in the form of phosphatidylcholine, and of the classical homocysteine-lowering vitamin folic acid on blood lipid concentrations in healthy humans. METHODS AND FINDINGS: We measured blood lipids in four placebo-controlled, randomised intervention studies that examined the effect of betaine (three studies, n = 151, folic acid (two studies, n = 75, and phosphatidylcholine (one study, n = 26 on plasma homocysteine concentrations. We combined blood lipid data from the individual studies and calculated a weighted mean change in blood lipid concentrations relative to placebo. Betaine supplementation (6 g/d for 6 wk increased blood LDL cholesterol concentrations by 0.36 mmol/l (95% confidence interval: 0.25-0.46, and triacylglycerol concentrations by 0.14 mmol/l (0.04-0.23 relative to placebo. The ratio of total to HDL cholesterol increased by 0.23 (0.14-0.32. Concentrations of HDL cholesterol were not affected. Doses of betaine lower than 6 g/d also raised LDL cholesterol, but these changes were not statistically significant. Further, the effect of betaine on LDL cholesterol was already evident after 2 wk of intervention. Phosphatidylcholine supplementation (providing approximately 2.6 g/d of choline for 2 wk increased triacylglycerol concentrations by 0.14 mmol/l (0.06-0.21, but did not affect cholesterol concentrations. Folic acid supplementation (0.8 mg/d had no effect on lipid concentrations. CONCLUSIONS: Betaine supplementation increased blood LDL cholesterol and triacylglycerol

  14. Lipid chain geometry of C14 glycerol-based lipids: effect on lipoplex structure and transfection.

    Science.gov (United States)

    Kudsiova, Laila; Ho, Jimmy; Fridrich, Barbara; Harvey, Richard; Keppler, Melanie; Ng, Tony; Hart, Stephen L; Tabor, Alethea B; Hailes, Helen C; Lawrence, M Jayne

    2011-02-01

    The effects have been determined of a systematic alteration of the alkyl chain geometry of a C14 analogue of DOTMA on the detailed molecular architecture of the resulting cationic vesicles formed both in the absence and presence of 50 mol% DOPE, and of the lipoplexes prepared from these vesicles using either calf thymus or plasmid DNA. The C14 DOTMA analogues studied involved cis- or trans-double bonds at positions Δ9 or Δ11, and a compound (ALK) featuring an alkyne at position C9. For all of these analogues, examination by light scattering and neutron scattering, zeta potential measurement, and negative staining electron microscopy showed that there were no significant differences in the structures or charges of the vesicles or of the resulting lipoplexes, regardless of the nature of the DNA incorporated. Differences were observed, however, between the complexes formed by the various lipids when examining the extent of complexation and release by gel electrophoresis, where the E-lipids appeared to complex the DNA more efficiently than all other lipids tested. Moreover, the lipoplexes prepared from the E-lipids were the most effective in transfection of MDA-MB-231 breast cancer cells. As indicated through confocal microscopy studies, the E-lipids also showed a higher internalisation capacity and a more diffuse cellular distribution, possibly indicating a greater degree of endosomal escape and/or nuclear import. These observations suggest that the extent of complexation is the most important factor in determining the transfection efficiency of the complexes tested. At present it is unclear why the E-lipids were more effective at complexing DNA, although it is thought that the effective area per molecule occupied by the cationic lipid and DOPE head groups, and therefore the density of positive charges on the surface of the bilayer most closely matches the negative charge density of the DNA molecule. From a consideration of the geometry of the cationic lipids it is

  15. Oral fondaparinux: use of lipid nanocapsules as nanocarriers and in vivo pharmacokinetic study

    Directory of Open Access Journals (Sweden)

    Ramadan A

    2011-11-01

    Full Text Available Alyaa Ramadan1,4, Frederic Lagarce1,3, Anne Tessier-Marteau2, Olivier Thomas1, Pierre Legras5, Laurent Macchi2, Patrick Saulnier1, Jean Pierre Benoit1,31LUNAM Université, Ingénierie de la Vectorisation Particulaire, Inserm U-646, Angers, France; 2Hematology Department, Angers University Hospital, Angers, France; 3Department of Pharmacy, Angers University Hospital, Angers, France; 4Department of Pharmaceutics, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt; 5SCAHU, Animal House, Angers, FranceAbstract: Oral anticoagulant therapy could be advanced using lipid-based nanoparticulate systems. This study examined lipid nanocapsules for their oral absorption potential as the first step in developing oral fondaparinux (Fp novel carriers. Using phase inversion method and cationic surfactants such as hexadecyltrimethyl ammonium bromide (CTAB or stearylamine (SA, cationic lipid nanocapsules (cLNCs, loaded with Fp on their surface, were prepared and characterized (zeta potential, size and Fp association efficiency and content. In vivo studies were conducted after single oral increasing doses of Fp-loaded cLNCs (0.5 to 5 mg/kg of Fp in rats and the concentration of Fp in the plasma was measured by anti-factor Xa activity assay. The monodisperse, (~50 nm, positively charged Fp-cLNCs with high drug loadings demonstrated linear pharmacokinetic profiles of the drug with an increased oral absolute bioavailability (up to ~21% compatible with therapeutic anticoagulant effect (>0.2 µg/mL.Keywords: oral anticoagulant, fondaparinux, lipid nanocapsules, bioavailability, pharmacokinetics, rats

  16. Chronic Kidney Disease and Lipid Disorders.

    Science.gov (United States)

    Zubovic, Sandra Vegar; Kristic, Spomenka; Prevljak, Sabina; Pasic, Irmina Sefic

    2016-06-01

    Chronic kidney disease (CKD) represents a serious public health problem due to the increase in incidence and prevalence of this disease worldwide. Given the significant morbidity and mortality from cardiovascular disease (CVD) in the population of patients with CKD, and the fact that dyslipidemia itself is a risk factor for CVD, increases the importance of lipid metabolism study in patients with CKD. Evaluate the lipid status of patients with chronic kidney disease. A one-year prospective study included 150 adult patients who were in various stages of chronic renal failure (stage I to IV). Estimate of creatinine clearance was performed using Cockroft-Goult formula. The classification of patients according to stages of chronic renal insufficiency was performed in accordance with the criteria of Kidney Disease Outcomes Quality Initiative (K/DOQI). Of the total number of patients (N=150) there was 71 males and 79 females. The mean age of patients was 55.43 years. Average values of serum cholesterol were highest in patients with stage II renal disease and the lowest in patients classified as stage IV (5.76±1.60 mmol/L vs. 5.07±1.88 mmol/L). Analysis of the average value of triglycerides in blood show a slight increase through the stages of CKD in a manner that patients classified into stage I have low serum triglyceride levels (1.73±1.17 mmol/L (range 0.61 to 5.5 mmol/L), and patients classified in stage III the highest value 2.13±1.11 mmol/L (range 0.62 to 4.66 mmol/L). Average cholesterol levels does not statistically significantly change with progression of chronic renal disease. There is an almost linear increase in average triglyceride levels in chronic renal disease. Triglyceride levels in serum begins to increase in the early stage of chronic renal disease and reach the peak in stage IV.

  17. A lipid storage-like disorder contributes to cognitive decline in HIV-infected subjects.

    Science.gov (United States)

    Bandaru, Veera Venkata Ratnam; Mielke, Michelle M; Sacktor, Ned; McArthur, Justin C; Grant, Igor; Letendre, Scott; Chang, Linda; Wojna, Valerie; Pardo, Carlos; Calabresi, Peter; Munsaka, Sody; Haughey, Norman J

    2013-10-22

    In this multicenter cohort study, we sought to identify prognostic and associative metabolic indicators for HIV-associated neurocognitive disorders (HAND). A quantitative lipidomic analysis was conducted on 524 longitudinal CSF samples collected from 7 different performance sites across the mainland United States, Hawaii, and Puerto Rico. Subjects included HIV-infected individuals with longitudinal clinical and cognitive testing data and cognitively normal HIV-negative healthy controls. At baseline, HIV+ subjects could be differentiated from HIV- controls by reductions in a single ceramide species and increases in multiple forms of cholesterol. Perturbations in cholesterol metabolism and ceramide were influenced by combined antiretroviral therapy (cART) use. There were no cross-sectional baseline differences in any lipid metabolite when HIV+ subjects were grouped according to cognitive status. However, a single sphingolipid metabolite and reduced levels of esterified cholesterols were prognostic indicators of incident cognitive decline. Longitudinal patterns of these disturbances in sphingolipid and sterol metabolism suggest that a progressive disorder of lipid metabolism that is similar to disorders of lipid storage may contribute to the pathogenesis of HAND. These findings suggest that HIV infection and cART are independently associated with a CNS metabolic disturbance, identify surrogate markers that are prognostic for cognitive decline, and implicate a lipid storage-like disorder in the progression of HAND.

  18. The solubilisation of boar sperm membranes by different detergents - a microscopic, MALDI-TOF MS, 31P NMR and PAGE study on membrane lysis, extraction efficiency, lipid and protein composition

    Directory of Open Access Journals (Sweden)

    Müller Karin

    2009-11-01

    Full Text Available Abstract Background Detergents are often used to isolate proteins, lipids as well as "detergent-resistant membrane domains" (DRMs from cells. Different detergents affect different membrane structures according to their physico-chemical properties. However, the effects of different detergents on membrane lysis of boar spermatozoa and the lipid composition of DRMs prepared from the affected sperm membranes have not been investigated so far. Results Spermatozoa were treated with the selected detergents Pluronic F-127, sodium cholate, CHAPS, Tween 20, Triton X-100 and Brij 96V. Different patterns of membrane disintegration were observed by light and electron microscopy. In accordance with microscopic data, different amounts of lipids and proteins were released from the cells by the different detergents. The biochemical methods to assay the phosphorus and cholesterol contents as well as 31P NMR to determine the phospholipids were not influenced by the presence of detergents since comparable amounts of lipids were detected in the organic extracts from whole cell suspensions after exposure to each detergent. However, matrix-assisted laser desorption and ionization time-of-flight mass spectrometry applied to identify phospholipids was essentially disturbed by the presence of detergents which exerted particular suppression effects on signal intensities. After separation of the membrane fractions released by detergents on a sucrose gradient only Triton X-100 and sodium cholate produced sharp turbid DRM bands. Only membrane solubilisation by Triton X-100 leads to an enrichment of cholesterol, sphingomyelin, phosphatidylinositol and phosphatidylethanolamine in a visible DRM band accompanied by a selective accumulation of proteins. Conclusion The boar sperm membranes are solubilised to a different extent by the used detergents. Particularly, the very unique DRMs isolated after Triton X-100 exposure are interesting candidates for further studies regarding the

  19. Effect of tea catechins on the structure of lipid membrane and beta-ray induced lipid peroxidation

    International Nuclear Information System (INIS)

    Kubota, M.; Haga, H.; Takeuchi, Y.; Okuno, K.; Yoshioka, H.; Yoshioka, H.

    2007-01-01

    Inhibiting effect of four tea catechins, (-)-epicatechin (EC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin (EGC), (-)-epigallocatechin gallate (EGCG), on the lipid peroxidation induced by β-ray in tritiated water was examined using a spin probe method. 16-Doxylstearic acid (16NS) was incorporated into the liposome prepared from egg yolk phosphatidylcholine and the rate of the decrease of ESR intensity of 16NS was used as a measure of the inhibiting effect. In the low concentration region below 10 -5 M, catechins showed their inhibitions on the lipid peroxidation according to the order of ECG>EGCG>EC>EGC. This result was explained by a model that the initiator of the peroxidation is the hydroxyl radical (·OH) and the catechins adsorbed on the lipid membrane surface acting as scavengers of ·OH. In the high concentration range, however, the effect was diverse and it decreased with the increase of it in the case of EGCG. EGCG in this range was considered to enter into the interior of the membrane and break the structure, which causes the decrease of 16NS. Observation with transmission electron microscope (TEM) revealed that the size of the liposome became larger with the increasing concentration of EGCG and finally it was broken into fragments, showing that EGCG broadened the area of the liposome as expected from the result of ESR. (author)

  20. Surfactant properties of human meibomian lipids.

    Science.gov (United States)

    Mudgil, Poonam; Millar, Thomas J

    2011-03-25

    Human meibomian lipids are the major part of the lipid layer of the tear film. Their surfactant properties enable their spread across the aqueous layer and help maintain a stable tear film. The purpose of this study was to investigate surfactant properties of human meibomian lipids in vitro and to determine effects of different physical conditions such as temperature and increased osmolarity, such as occur in dry eye, on these properties. Human meibomian lipids were spread on an artificial tear solution in a Langmuir trough. The lipid films were compressed and expanded to record the surface pressure-area (Π-A) isocycles. The isocycles were recorded under different physical conditions such as high pressure, increasing concentration and size of divalent cations, increasing osmolarity, and varying temperature. Π-A isocycles of meibomian lipids showed that they form liquid films that are compressible and multilayered. The isocycles were unaffected by increasing concentration or size of divalent cations and increasing osmolarity in the subphase. Temperature had a marked effect on the lipids. Increase in temperature caused lipid films to become fluid, an expected feature, but decrease in temperature unexpectedly caused expansion of lipids and an increase in pressure suggesting enhanced surfactant properties. Human meibomian lipids form highly compressible, non-collapsible, multilayered liquid films. These lipids have surfactants that allow them to spread across an aqueous subphase. Their surfactant properties are unaffected by increasing divalent cations or hyperosmolarity but are sensitive to temperature. Cooling of meibomian lipids enhances their surfactant properties.

  1. Study on the lipid organization of stratum corneum lipid models by (cryo-) electron diffraction

    NARCIS (Netherlands)

    Pilgram, GSK; Pelt, AMEV; Oostergetel, GT; Koerten, HK; Bouwstra, JA

    The barrier function of the skin resides in the stratum corneum (SC), This outermost layer consists of protein-rich corneocytes and lipid-rich intercellular domains. These domains form the rate-limiting step for transepidermal water loss and the penetration of substances from the environment. To

  2. Marine crenarchaeotal membrane lipids in decapods: Implications for the TEX86 paleothermometer

    NARCIS (Netherlands)

    Huguet, C.; Cartes, J.E.; Sinninghe Damsté, J.S.; Schouten, S.

    2006-01-01

    Pelagic Crenarchaeota produce glycerol dibiphytanyl glycerol tetraethers (GDGTs) as membrane lipids, and the GDGT composition changes according to growth temperature. This forms the basis of the TEX86 paleotemperature proxy. This ratio correlates with sea surface temperature (SST) despite the fact

  3. Release and diffusional modeling of metronidazole lipid matrices.

    Science.gov (United States)

    Ozyazici, Mine; Gökçe, Evren H; Ertan, Gökhan

    2006-07-01

    In this study, the first aim was to investigate the swelling and relaxation properties of lipid matrix on diffusional exponent (n). The second aim was to determine the desired release profile of metronidazole lipid matrix tablets. We prepared metronidazole lipid matrix granules using Carnauba wax, Beeswax, Stearic acid, Cutina HR, Precirol ATO 5, and Compritol ATO 888 by hot fusion method and pressed the tablets of these granules. In vitro release test was performed using a standard USP dissolution apparatus I (basket method) with a stirring rate of 100 rpm at 37 degrees C in 900 ml of 0.1 N hydrochloric acid, adjusted to pH 1.2, as medium for the formulations' screening. Hardness, diameter-height ratio, friability, and swelling ratio were determined. Target release profile of metronidazole was also drawn. Stearic acid showed the highest and Carnauba wax showed the lowest release rates in all formulations used. Swelling ratios were calculated after the dissolution of tablets as 9.24%, 6.03%, 1.74%, and 1.07% for Cutina HR, Beeswax, Precirol ATO 5, and Compritol ATO 888, respectively. There was erosion in Stearic acid, but neither erosion nor swelling in Carnauba wax, was detected. According to the power law analysis, the diffusion mechanism was expressed as pure Fickian for Stearic acid and Carnauba wax and the coupling of Fickian and relaxation contributions for other Cutina HR, Beeswax, Compritol ATO 888, and Precirol ATO 5 tablets. It was found that Beeswax (kd=2.13) has a very close drug release rate with the target profile (kt=1.95). Our results suggested that swelling and relaxation properties of lipid matrices should be examined together for a correct evaluation on drug diffusion mechanism of insoluble matrices.

  4. Steroidal Compounds in Commercial Parenteral Lipid Emulsions

    Science.gov (United States)

    Xu, Zhidong; Harvey, Kevin A.; Pavlina, Thomas; Dutot, Guy; Hise, Mary; Zaloga, Gary P.; Siddiqui, Rafat A.

    2012-01-01

    Parenteral nutrition lipid emulsions made from various plant oils contain steroidal compounds, called phytosterols. During parenteral administration of lipid emulsions, phytosterols can reach levels in the blood that are many fold higher than during enteral administration. The elevated phytosterol levels have been associated with the development of liver dysfunction and the rare development of liver failure. There is limited information available in the literature related to phytosterol concentrations in lipid emulsions. The objective of the current study was to validate an assay for steroidal compounds found in lipid emulsions and to compare their concentrations in the most commonly used parenteral nutrition lipid emulsions: Liposyn® II, Liposyn® III, Lipofundin® MCT, Lipofundin® N, Structolipid®, Intralipid®, Ivelip® and ClinOleic®. Our data demonstrates that concentrations of the various steroidal compounds varied greatly between the eight lipid emulsions, with the olive oil-based lipid emulsion containing the lowest levels of phytosterols and cholesterol, and the highest concentration of squalene. The clinical impression of greater incidences of liver dysfunction with soybean versus MCT/LCT and olive/soy lipid emulsions may be reflective of the levels of phytosterols in these emulsions. This information may help guide future studies and clinical care of patients with lipid emulsion-associated liver dysfunction. PMID:23016123

  5. Steroidal compounds in commercial parenteral lipid emulsions.

    Science.gov (United States)

    Xu, Zhidong; Harvey, Kevin A; Pavlina, Thomas; Dutot, Guy; Hise, Mary; Zaloga, Gary P; Siddiqui, Rafat A

    2012-08-01

    Parenteral nutrition lipid emulsions made from various plant oils contain steroidal compounds, called phytosterols. During parenteral administration of lipid emulsions, phytosterols can reach levels in the blood that are many fold higher than during enteral administration. The elevated phytosterol levels have been associated with the development of liver dysfunction and the rare development of liver failure. There is limited information available in the literature related to phytosterol concentrations in lipid emulsions. The objective of the current study was to validate an assay for steroidal compounds found in lipid emulsions and to compare their concentrations in the most commonly used parenteral nutrition lipid emulsions: Liposyn(®) II, Liposyn(®) III, Lipofundin(®) MCT, Lipofundin(®) N, Structolipid(®), Intralipid(®), Ivelip(®) and ClinOleic(®). Our data demonstrates that concentrations of the various steroidal compounds varied greatly between the eight lipid emulsions, with the olive oil-based lipid emulsion containing the lowest levels of phytosterols and cholesterol, and the highest concentration of squalene. The clinical impression of greater incidences of liver dysfunction with soybean versus MCT/LCT and olive/soy lipid emulsions may be reflective of the levels of phytosterols in these emulsions. This information may help guide future studies and clinical care of patients with lipid emulsion-associated liver dysfunction.

  6. Features of lipid metabolism in chronic heart failure of different genesis with concomitant overweight and obesity

    Directory of Open Access Journals (Sweden)

    Р. P. Bidzilya

    2016-08-01

    Full Text Available Recently clinical studies demonstrated reciprocal association between traditional cardiovascular risk factors, in particular, hyperlipidemia and obesity, with worse clinical outcomes in CHF. Unlike ischemic heart disease (IHD, where high levels of atherogenic and low of antiatherogenic lipids fraction traditionally associated with worsening of prognosis and course of disease, in conditions of the CHF proven negative impact of the reduction of lipid levels and body mass index. Demonstrated the phenomena called "cholesterol paradox" and "obesity paradox". Aim. To study the features of lipid metabolism in CHF of different genesis with concomitant overweight and obesity. Materials and methods. 240 patients with I–III functional class (FC of the disease with concomitant overweight and abdominal obesity I–III degree were examined. FC of the disease was established according to the classification of New York Heart Association (NYHA.Normal, overweight and the degree of abdominal obesity was identified by calculating the body mass index. Etiologic factors of CHF were chronic forms of IHD, arterial hypertension, and/or a combination of both. With the help of biochemical blood tests lipid metabolism were assessed. Results. The maximum values as atherogenic and antiatherogenic lipid indicators are investigated in non-ischemic (hypertensive CHF. Patients with CHF of ischemic genesis are characterized by minimal values of atherogenic fractions of lipids. Patients with combined etiology of CHF occupy the intermediate position of atherogenic fractions content, while they demonstrate the minimum value in the antiatherogenic HDL-cholesterol. Conclusion. Changes of lipid metabolism are varied depending on the etiology of CHF in patients with concomitant overweight and obesity and the most unfavorable in ischemic form of the disease.

  7. Lipid somersaults

    DEFF Research Database (Denmark)

    Günther-Pomorski, Thomas; Menon, Anant K.

    2016-01-01

    Membrane lipids diffuse rapidly in the plane of the membrane but their ability to flip spontaneously across a membrane bilayer is hampered by a significant energy barrier. Thus spontaneous flip-flop of polar lipids across membranes is very slow, even though it must occur rapidly to support diverse...... aspects of cellular life. Here we discuss the mechanisms by which rapid flip-flop occurs, and what role lipid flipping plays in membrane homeostasis and cell growth. We focus on conceptual aspects, highlighting mechanistic insights from biochemical and in silico experiments, and the recent, ground......-breaking identification of a number of lipid scramblases....

  8. Production of lipids in 10 strains of Chlorella and Parachlorella, and enhanced lipid productivity in Chlorella vulgaris

    Energy Technology Data Exchange (ETDEWEB)

    Pribyl, Pavel; Cepak, Vladislav [Academy of Sciences of the Czech Republic, Trebon (Czech Republic). Algological Centre and Centre for Bioindication and Revitalization; Zachleder, Vilem [Academy of Sciences of the Czech Republic, Trebon (Czech Republic). Lab. of the Cell Cycles of Algae

    2012-04-15

    We tested 10 different Chlorella and Parachlorella strains under lipid induction growth conditions in autotrophic laboratory cultures. Between tested strains, substantial differences in both biomass and lipid productivity as well as in the final content of lipids were found. The most productive strain (Chlorella vulgaris CCALA 256) was subsequently studied in detail. The availability of nitrates and/or phosphates strongly influenced growth and accumulation of lipids in cells by affecting cell division. Nutrient limitation substantially enhanced lipid productivity up to a maximal value of 1.5 g l{sup -1} day{sup -1}. We also demonstrated the production of lipids through large-scale cultivation of C. vulgaris in a thin layer photobioreactor, even under suboptimal conditions. After 8 days of cultivation, maximal lipid productivity was 0.33 g l{sup -1} day{sup -1}, biomass density was 5.7 g l{sup -1} dry weight and total lipid content was more than 30% dry weight. C. vulgaris lipids comprise fatty acids with a relatively high degree of saturation compared with canola oil offering a possible alternative to the use of higher plant oils. (orig.)

  9. JAZF1 can regulate the expression of lipid metabolic genes and inhibit lipid accumulation in adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Ming, Guang-feng [Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha 410078, Hunan (China); Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, Hunan (China); Xiao, Di; Gong, Wei-jing [Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha 410078, Hunan (China); Liu, Hui-xia; Liu, Jun [Department of Geriatrics, Xiangya Hospital, Central South University, Changsha 410008, Hunan (China); Zhou, Hong-hao [Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha 410078, Hunan (China); Liu, Zhao-qian, E-mail: liuzhaoqian63@126.com [Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha 410078, Hunan (China)

    2014-03-14

    Highlights: • JAZF1 was significantly upregulated during the differentiation of 3T3-L1 preadipocytes. • JAZF1 overexpression inhibited lipid accumulation in differentiated mature 3T3-L1 adipocytes. • JAZF1 overexpression inhibited the expression of SREBP1, ACC, and FAS. • JAZF1 overexpression upregulated the expression of HSL and ATGL. • SREBP1 and JAZF1 could regulate each other in adipocytes. - Abstract: JAZF1 is a newly identified gene with unknown functions. A recent genome-wide association study showed that JAZF1 is associated with type 2 diabetes and is highly expressed in liver and adipose tissue. Studies have demonstrated that JAZF1 is the co-repressor for nuclear orphan receptor TAK1, whereas most nuclear orphan receptor family members are involved in the regulation of lipid metabolism. Therefore, JAZF1 could be closely related to glycolipid metabolism. In this study, JAZF1 was significantly upregulated during the induced differentiation process of 3T3-L1 preadipocytes. The overexpression of JAZF1 inhibited lipid accumulation in differentiated mature 3T3-L1 adipocytes and significantly inhibited the expression of SREBPl, ACC, and FAS, which were important in lipid synthesis, while upregulating the expression of key enzyme hormone-sensitive lipase in lipoclasis. Moreover, SREBPl exhibited an inhibitory function on the expression of JAZF1. SREBP1 reversed the inhibitory action on lipid accumulation of JAZF1. SREBP1 and JAZF1 were observed to regulate each other in adipocytes. Therefore, JAZF1 could regulate the expression of particular genes related to lipid metabolism and inhibit lipid accumulation in adipocytes. This result suggests that JAZF1 may be a potential target for the treatment of diseases, such as obesity and lipid metabolism disorders.

  10. JAZF1 can regulate the expression of lipid metabolic genes and inhibit lipid accumulation in adipocytes

    International Nuclear Information System (INIS)

    Ming, Guang-feng; Xiao, Di; Gong, Wei-jing; Liu, Hui-xia; Liu, Jun; Zhou, Hong-hao; Liu, Zhao-qian

    2014-01-01

    Highlights: • JAZF1 was significantly upregulated during the differentiation of 3T3-L1 preadipocytes. • JAZF1 overexpression inhibited lipid accumulation in differentiated mature 3T3-L1 adipocytes. • JAZF1 overexpression inhibited the expression of SREBP1, ACC, and FAS. • JAZF1 overexpression upregulated the expression of HSL and ATGL. • SREBP1 and JAZF1 could regulate each other in adipocytes. - Abstract: JAZF1 is a newly identified gene with unknown functions. A recent genome-wide association study showed that JAZF1 is associated with type 2 diabetes and is highly expressed in liver and adipose tissue. Studies have demonstrated that JAZF1 is the co-repressor for nuclear orphan receptor TAK1, whereas most nuclear orphan receptor family members are involved in the regulation of lipid metabolism. Therefore, JAZF1 could be closely related to glycolipid metabolism. In this study, JAZF1 was significantly upregulated during the induced differentiation process of 3T3-L1 preadipocytes. The overexpression of JAZF1 inhibited lipid accumulation in differentiated mature 3T3-L1 adipocytes and significantly inhibited the expression of SREBPl, ACC, and FAS, which were important in lipid synthesis, while upregulating the expression of key enzyme hormone-sensitive lipase in lipoclasis. Moreover, SREBPl exhibited an inhibitory function on the expression of JAZF1. SREBP1 reversed the inhibitory action on lipid accumulation of JAZF1. SREBP1 and JAZF1 were observed to regulate each other in adipocytes. Therefore, JAZF1 could regulate the expression of particular genes related to lipid metabolism and inhibit lipid accumulation in adipocytes. This result suggests that JAZF1 may be a potential target for the treatment of diseases, such as obesity and lipid metabolism disorders

  11. Exogenous and endogenous lipids of human hair.

    Science.gov (United States)

    Coderch, L; Oliver, M A; Martínez, V; Manich, A M; Rubio, L; Martí, M

    2017-11-01

    The aim of this study was to characterize the external and internal lipids of Caucasian hair and their influence in different hair properties such as moisture content, hydrophobic character, and mechanical properties. Lipid extraction and their analysis by thin layer chromatography with flame ionization detector were carried out. Lipid rearrangement and water sorption and desorption evaluation of these fibers with and without lipids will also be determined using different techniques such as differential scanning calorimetry, thermogravimetric analysis and dynamic vapor sorption, mainly to evaluate permeation changes of these hair fibers possibly related to the fluidity of the lipids extracted. Caucasian fibers were found to be well hydrated, and moisture diminution was observed mainly for the external lipid extracted fibers. Unexpectedly, the lipid extraction promoted an increase in the break tenacity of the Caucasian fibers. The hydrophobic character of the fiber surfaces indicates the marked hydrophobicity of all fibers. Delipidization promotes only a slight diminution of their hydrophobic properties. Water uptake and desorption studies indicate an important water regain for Caucasian fibers. The external extracted hair fibers presented a diminution of maximum water regain, which surprisingly increases with the following internal lipid extraction. This can be due to a higher water desorption found only for external extracted fibers. The relationship between fluidity of lipids extracted and hair fiber water diffusion were established. Extraction of internal lipids of Caucasian fibers, which have a higher unsaturated lipid content than external lipids of the same hair fiber, leads to a lower water permeability of the fiber. On the capillar formulations should be considered the importance of lipid fluidity to modify the permeability of the fiber. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Muscle Lipid Metabolism: Role of Lipid Droplets and Perilipins

    Directory of Open Access Journals (Sweden)

    Pablo Esteban Morales

    2017-01-01

    Full Text Available Skeletal muscle is one of the main regulators of carbohydrate and lipid metabolism in our organism, and therefore, it is highly susceptible to changes in glucose and fatty acid (FA availability. Skeletal muscle is an extremely complex tissue: its metabolic capacity depends on the type of fibers it is made up of and the level of stimulation it undergoes, such as acute or chronic contraction. Obesity is often associated with increased FA levels, which leads to the accumulation of toxic lipid intermediates, oxidative stress, and autophagy in skeletal fibers. This lipotoxicity is one of the most common causes of insulin resistance (IR. In this scenario, the “isolation” of certain lipids in specific cell compartments, through the action of the specific lipid droplet, perilipin (PLIN family of proteins, is conceived as a lifeguard compensatory strategy. In this review, we summarize the cellular mechanism underlying lipid mobilization and metabolism inside skeletal muscle, focusing on the function of lipid droplets, the PLIN family of proteins, and how these entities are modified in exercise, obesity, and IR conditions.

  13. Study of lipid profile and parieto-temporal lipid peroxidation in AlCl3 mediated neurotoxicity. modulatory effect of fenugreek seeds

    Directory of Open Access Journals (Sweden)

    Belaïd-Nouira Yosra

    2012-01-01

    Full Text Available Abstract Background Peroxidation of lipid (LPO membrane and cholesterol metabolism have been involved in the physiopathology of many diseases of aging brain. Therefore, this prospective animal study was carried firstly to find out the correlation between LPO in posterior brain and plasmatic cholesterol along with lipoprotein levels after chronic intoxication by aluminium chloride (AlCl3. Chronic aluminum-induced neurotoxicity has been in fact related to enhanced brain lipid peroxidation together with hypercholesterolemia and hypertriglyceridemia, despite its controversial etiological role in neurodegenerative diseases. Secondly an evaluation of the effectiveness of fenugreek seeds in alleviating the engendered toxicity through these biochemical parameters was made. Results Oral administration of AlCl3 to rats during 5 months (500 mg/kg bw i.g for one month then 1600 ppm via the drinking water enhanced the levels of LPO in posterior brain, liver and plasma together with lactate dehydrogenase (LDH activities, total cholesterol (TC, triglycerides (TG and LDL-C (Low Density Lipoproteins levels. All these parameters were decreased following fenugreek seeds supplementation either as fenugreek seed powder (FSP or fenugreek seed extract (FSE. A notable significant correlation was observed between LPObrain and LDL-C on one hand and LDHliver on the other hand. This latter was found to correlate positively with TC, TG and LDL-C. Furthermore, high significant correlations were observed between LDHbrain and TC, TG, LDL-C, LPObrain as well as LDHliver. Conclusion Aluminium-induced LPO in brain could arise from alteration of lipid metabolism particularly altered lipoprotein metabolism rather than a direct effect of cholesterol oxidation. Fenugreek seeds could play an anti-peroxidative role in brain which may be attributed in part to its modulatory effect on plasmatic lipid metabolism.

  14. Combined effects of headgroup charge and tail unsaturation of lipids on lateral organization and diffusion of lipids in model biomembranes

    International Nuclear Information System (INIS)

    Chen Xiao-Jie; Liang Qing

    2017-01-01

    Lateral organization and dynamics of lipids in plasma membranes are crucial for several cellular processes such as signal transduction across the membrane and still remain elusive. In this paper, using coarse-grained molecular dynamics simulation, we theoretically study the combined effects of headgroup charge and tail unsaturation of lipids on the lateral organization and diffusion of lipids in ternary lipid bilayers. In neutral ternary lipid bilayers composed of saturated lipids, unsaturated lipids, and cholesterols, under the conditions of given temperature and components, the main factor for the phase separation is the unsaturation of unsaturated lipids and the bilayers can be separated into liquid-ordered domains enriched in saturated lipids and cholesterols and liquid-disordered domains enriched in unsaturated lipids. Once the headgroup charge is introduced, the electrostatic repulsion between the negatively charged lipid headgroups will increase the distance between the charged lipids. We find that the lateral organization and diffusion of the lipids in the (partially) charged ternary lipid bilayers are determined by the competition between the headgroup charge and the unsaturation of the unsaturated lipids. In the bilayers containing unsaturated lipids with lower unsaturation, the headgroup charge plays a crucial role in the lateral organization and diffusion of lipids. The headgroup charge may make the lipid domains unstable and even can suppress phase separation of the lipids in some systems. However, in the bilayers containing highly unsaturated lipids, the lateral organization and diffusion of lipids are mainly dominated by the unsaturation of the unsaturated lipids. This work may provide some theoretical insights into understanding the formation of nanosized domains and lateral diffusion of lipids in plasma membranes. (paper)

  15. A study on the effect of resveratrol on lipid metabolism in ...

    African Journals Online (AJOL)

    The objective of this paper was to study the effect of resveratrol on lipid metabolism in hyperlipidemia mice. Materials andMethods: Through the establishment of an experimental mouse model of hyperlipidemia, the effect of resveratrol on change in total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol ...

  16. Lipid-lowering nutraceuticals in clinical practice: position paper from an International Lipid Expert Panel.

    Science.gov (United States)

    Cicero, Arrigo F G; Colletti, Alessandro; Bajraktari, Gani; Descamps, Olivier; Djuric, Dragan M; Ezhov, Marat; Fras, Zlatko; Katsiki, Niki; Langlois, Michel; Latkovskis, Gustavs; Panagiotakos, Demosthenes B; Paragh, Gyorgy; Mikhailidis, Dimitri P; Mitchenko, Olena; Paulweber, Bernhard; Pella, Daniel; Pitsavos, Christos; Reiner, Željko; Ray, Kausik K; Rizzo, Manfredi; Sahebkar, Amirhossein; Serban, Maria-Corina; Sperling, Laurence S; Toth, Peter P; Vinereanu, Dragos; Vrablík, Michal; Wong, Nathan D; Banach, Maciej

    2017-09-01

    In recent years, there has been growing interest in the possible use of nutraceuticals to improve and optimize dyslipidemia control and therapy. Based on the data from available studies, nutraceuticals might help patients obtain theraputic lipid goals and reduce cardiovascular residual risk. Some nutraceuticals have essential lipid-lowering properties confirmed in studies; some might also have possible positive effects on nonlipid cardiovascular risk factors and have been shown to improve early markers of vascular health such as endothelial function and pulse wave velocity. However, the clinical evidence supporting the use of a single lipid-lowering nutraceutical or a combination of them is largely variable and, for many of the nutraceuticals, the evidence is very limited and, therefore, often debatable. The purpose of this position paper is to provide consensus-based recommendations for the optimal use of lipid-lowering nutraceuticals to manage dyslipidemia in patients who are still not on statin therapy, patients who are on statin or combination therapy but have not achieved lipid goals, and patients with statin intolerance. This statement is intended for physicians and other healthcare professionals engaged in the diagnosis and management of patients with lipid disorders, especially in the primary care setting. © The Author(s) 2017. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  17. Metabolism of lipids in Epidermophyton floccosum

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, A; Khuller, G K [Post-Graduate Inst. of Medical Education and Research, Chandigarh (India)

    1981-03-01

    Metabolism of major lipids in E. floccosum was studied with /sup 14/C-acetate as a precursor. Among the phosphatides, phosphatidylcholine exhibited the maximum rate of synthesis and degradation, followed by phosphatidylethanolamine and phosphatidylserine. These phospholipids appear to exist in two pools, one metabolically more active than the other. In neutral lipids, maximum uptake was observed in triglycerides, followed by free fatty acids, diglycerides and monoglycerides. However, on chase of the labelled lipids, a continuous synthesis of all neutral lipid fractions was observed suggesting a recycling of the labelled carbon.

  18. Studies on lipids and fatty acids in rats with streptozotocin-induced insulin deficiency II. Incorporation of 1-(14)C-sodium acetate into lipids and fatty acids of liver slices and whole blood cells

    OpenAIRE

    三宅,寛治

    1988-01-01

    In order to study the lipid and fatty acid metabolism in the insulin deficient state, the in vitro incorporation of 1-(14)C-sodium acetate into major lipid fractions and fatty acids of liver slices and whole blood cells was determined. Rats were studied one week, one month and three months after insulin deficiency was induced by administration of streptozotocin.The net incorporation of (14)C into lipid fractions and total fatty acids of liver slices significantly decreased after one week. On ...

  19. RaftProt: mammalian lipid raft proteome database.

    Science.gov (United States)

    Shah, Anup; Chen, David; Boda, Akash R; Foster, Leonard J; Davis, Melissa J; Hill, Michelle M

    2015-01-01

    RaftProt (http://lipid-raft-database.di.uq.edu.au/) is a database of mammalian lipid raft-associated proteins as reported in high-throughput mass spectrometry studies. Lipid rafts are specialized membrane microdomains enriched in cholesterol and sphingolipids thought to act as dynamic signalling and sorting platforms. Given their fundamental roles in cellular regulation, there is a plethora of information on the size, composition and regulation of these membrane microdomains, including a large number of proteomics studies. To facilitate the mining and analysis of published lipid raft proteomics studies, we have developed a searchable database RaftProt. In addition to browsing the studies, performing basic queries by protein and gene names, searching experiments by cell, tissue and organisms; we have implemented several advanced features to facilitate data mining. To address the issue of potential bias due to biochemical preparation procedures used, we have captured the lipid raft preparation methods and implemented advanced search option for methodology and sample treatment conditions, such as cholesterol depletion. Furthermore, we have identified a list of high confidence proteins, and enabled searching only from this list of likely bona fide lipid raft proteins. Given the apparent biological importance of lipid raft and their associated proteins, this database would constitute a key resource for the scientific community. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  20. CHARACTERISTICS OF LIPID METABOLISM IN PATIENTS WITH TYPE 1 DIABETES, DEPENDING ON THE AVAILABILITY OF DIABETIC MICROANGIOPATHY AND DIET

    Directory of Open Access Journals (Sweden)

    Yu. G. Samoilova

    2014-01-01

    Full Text Available Was investigated 67 children (36 boys and 31 girls in age from 6 to 18 years old, with type 1 diabetes patients who were treated at the Children's Hospital Endocrinology number 1 inTomsk, average age of the boys at the time of the survey amounted to (13.0 ± 0.4 years, girls – (13.5 ± 0.4 years. All children diagnosed with type 1 diabetes were under subcompensation. Clinical evaluation of patients included a medical history, physical examination, evaluation of physical development. A study of lipid profile (high-density lipoprotein (HDL cholesterol, low-density lipoprotein (LDL, cholesterol (TC, triglycerides (TG, atherogenic index. Screening for diabetic retinopathy was performed by examining the fundus by direct ophthalmoscopy after pupil dilation. Diagnosis of diabetic nephropathy, retinopathy performed according to the classification. Patients were divided into groups depending on the presence of complications, and the level of compensation lipid metabolism (children with satisfactory compensation of lipid metabolism (total cholesterol level less than 5.2 mmol / l, children with poor compensation lipid metabolism (total cholesterol above 5.2 mmol / l. Nature of the subjects studied nutrition using  a questionnaire drawn up on the basis of the standard dietary questionnaire program CINDI, allowing to evaluate the eating habits by examining the frequency of intake of various foods, food preferences and priorities. Products, according to the lipid-lowering diet on the recommendations of the European Society for atherosclerosis were combined and divided into groups according to frequency of use: commonly used products, and rarely use the products. Mathematical treatment of the results was performed using the software package Statistica 5.5 for Windows. In the first phase expected to total group performance statistics – the arithmetic mean value M and the error of the mean m, as well as visualization of the distribution of values

  1. Extended synaptotagmins are Ca2+-dependent lipid transfer proteins at membrane contact sites.

    Science.gov (United States)

    Yu, Haijia; Liu, Yinghui; Gulbranson, Daniel R; Paine, Alex; Rathore, Shailendra S; Shen, Jingshi

    2016-04-19

    Organelles are in constant communication with each other through exchange of proteins (mediated by trafficking vesicles) and lipids [mediated by both trafficking vesicles and lipid transfer proteins (LTPs)]. It has long been known that vesicle trafficking can be tightly regulated by the second messenger Ca(2+), allowing membrane protein transport to be adjusted according to physiological demands. However, it remains unclear whether LTP-mediated lipid transport can also be regulated by Ca(2+) In this work, we show that extended synaptotagmins (E-Syts), poorly understood membrane proteins at endoplasmic reticulum-plasma membrane contact sites, are Ca(2+)-dependent LTPs. Using both recombinant and endogenous mammalian proteins, we discovered that E-Syts transfer glycerophospholipids between membrane bilayers in the presence of Ca(2+) E-Syts use their lipid-accommodating synaptotagmin-like mitochondrial lipid binding protein (SMP) domains to transfer lipids. However, the SMP domains themselves cannot transport lipids unless the two membranes are tightly tethered by Ca(2+)-bound C2 domains. Strikingly, the Ca(2+)-regulated lipid transfer activity of E-Syts was fully recapitulated when the SMP domain was fused to the cytosolic domain of synaptotagmin-1, the Ca(2+)sensor in synaptic vesicle fusion, indicating that a common mechanism of membrane tethering governs the Ca(2+)regulation of lipid transfer and vesicle fusion. Finally, we showed that microsomal vesicles isolated from mammalian cells contained robust Ca(2+)-dependent lipid transfer activities, which were mediated by E-Syts. These findings established E-Syts as a novel class of LTPs and showed that LTP-mediated lipid trafficking, like vesicular transport, can be subject to tight Ca(2+)regulation.

  2. Serum prolactin, leptin, lipids and lipoproteins levels during antipsychotics treatment in Parkinson's disease and related psychosis.

    Science.gov (United States)

    Rustembegovic, Avdo; Sofic, Emin; Wichart, Ildiko

    2006-01-01

    Weight gain is a common adverse effect associated with the use of most typical and atypical antipsychotic. Aim of this study was to investigate serum prolactin, leptin, cholesterol, triglyceride, lipoproteins, such high density lipoprotein (HDL), and low density lipoprotein (LDL) levels in patients with Parkinson's disease (PD)-related psychosis during long-term medication with atypical antipsychotic. The study population comprised 40 patients, who were divided into 4 groups: olanzapine (n=10), risperidone (n=10), seroquel (n=10) monotherapy, a group of 10 patients receiving only antiparkinson drugs and a control group of 8 healthy persons. The patients were evaluated at baseline and at the sixth and twelfth week according to the Positive and Negative Syndrome Scale (PANSS), body mass index (BMI), and fasting serum prolactin, leptin, lipids and lipoproteins levels. Treatment of patients with olanzapine caused marked increase of serum LDL, cholesterol, triglyceride, and leptin levels (prelationship between serum leptin, lipid levels and BMI. However, treatment of patients with seroquel did not cause changes in serum prolactin, leptin, lipids, and lipoproteins levels. Our results suggest that treatment of patients with PD-related psychosis with seroquel appears to have minimal influence on serum leptin, prolactin, lipids, lipoproteins and BMI compared with olanzapine and risperidone.

  3. Steroidal Compounds in Commercial Parenteral Lipid Emulsions

    Directory of Open Access Journals (Sweden)

    Rafat A. Siddiqui

    2012-08-01

    Full Text Available Parenteral nutrition lipid emulsions made from various plant oils contain steroidal compounds, called phytosterols. During parenteral administration of lipid emulsions, phytosterols can reach levels in the blood that are many fold higher than during enteral administration. The elevated phytosterol levels have been associated with the development of liver dysfunction and the rare development of liver failure. There is limited information available in the literature related to phytosterol concentrations in lipid emulsions. The objective of the current study was to validate an assay for steroidal compounds found in lipid emulsions and to compare their concentrations in the most commonly used parenteral nutrition lipid emulsions: Liposyn® II, Liposyn® III, Lipofundin® MCT, Lipofundin® N, Structolipid®, Intralipid®, Ivelip® and ClinOleic®. Our data demonstrates that concentrations of the various steroidal compounds varied greatly between the eight lipid emulsions, with the olive oil-based lipid emulsion containing the lowest levels of phytosterols and cholesterol, and the highest concentration of squalene. The clinical impression of greater incidences of liver dysfunction with soybean versus MCT/LCT and olive/soy lipid emulsions may be reflective of the levels of phytosterols in these emulsions. This information may help guide future studies and clinical care of patients with lipid emulsion-associated liver dysfunction.

  4. Lipid profiling demonstrates that suppressing Arabidopsis phospholipase Dδ retards ABA-promoted leaf senescence by attenuating lipid degradation.

    Directory of Open Access Journals (Sweden)

    Yanxia Jia

    Full Text Available Senescence is the last phase of the plant life cycle and has an important role in plant development. Degradation of membrane lipids is an essential process during leaf senescence. Several studies have reported fundamental changes in membrane lipids and phospholipase D (PLD activity as leaves senesce. Suppression of phospholipase Dα1 (PLDα1 retards abscisic acid (ABA-promoted senescence. However, given the absence of studies that have profiled changes in the compositions of membrane lipid molecules during leaf senescence, there is no direct evidence that PLD affects lipid composition during the process. Here, we show that application of n-butanol, an inhibitor of PLD, and N-Acylethanolamine (NAE 12∶0, a specific inhibitor of PLDα1, retarded ABA-promoted senescence to different extents. Furthermore, phospholipase Dδ (PLDδ was induced in leaves treated with ABA, and suppression of PLDδ retarded ABA-promoted senescence in Arabidopsis. Lipid profiling revealed that detachment-induced senescence had different effects on plastidic and extraplastidic lipids. The accelerated degradation of plastidic lipids during ABA-induced senescence in wild-type plants was attenuated in PLDδ-knockout (PLDδ-KO plants. Dramatic increases in phosphatidic acid (PA and decreases in phosphatidylcholine (PC during ABA-induced senescence were also suppressed in PLDδ-KO plants. Our results suggest that PLDδ-mediated hydrolysis of PC to PA plays a positive role in ABA-promoted senescence. The attenuation of PA formation resulting from suppression of PLDδ blocks the degradation of membrane lipids, which retards ABA-promoted senescence.

  5. The Role of Lipids in Human Milk and Infant Formulae

    Directory of Open Access Journals (Sweden)

    Alessandra Mazzocchi

    2018-05-01

    Full Text Available The quantity and quality of dietary lipids in infant formulae have a significant impact on health outcomes, especially when fat storing and/or absorption are limited (e.g., preterm birth and short bowel disease or when fat byproducts may help to prevent some pathologies (e.g., atopy. The lipid composition of infant formulae varies according to the different fat sources used, and the potential biological effects are related to the variety of saturated and unsaturated fatty acids. For example, since lipids are the main source of energy when the normal absorptive capacity of the digestive tract is compromised, medium-chain saturated fatty acids might cover this requirement. Instead, ruminant-derived trans fatty acids and metabolites of n-3 long-chain polyunsaturated fatty acids with their anti-inflammatory properties can modulate immune function. Furthermore, dietary fats may influence the nutrient profile of formulae, improving the acceptance of these products and the compliance with dietary schedules.

  6. Tris(2-aminoethyl)amine-based α-branched fatty acid amides - Synthesis of lipids and comparative study of transfection efficiency of their lipid formulations.

    Science.gov (United States)

    Erdmann, Nicole; Wölk, Christian; Schulze, Ingo; Janich, Christopher; Folz, Manuela; Drescher, Simon; Dittrich, Matthias; Meister, Annette; Vogel, Jürgen; Groth, Thomas; Dobner, Bodo; Langner, Andreas

    2015-10-01

    The synthesis of a new class of cationic lipids, tris(2-aminoethyl)amine-based α-branched fatty acid amides, is described resulting in a series of lipids with specific variations in the lipophilic as well as the hydrophilic part of the lipids. In-vitro structure/transfection relationships were established by application of complexes of these lipids with plasmid DNA (pDNA) to different cell lines. The α-branched fatty acid amide bearing two tetradecyl chains and two lysine molecules (T14diLys) in mixture with the co-lipid 1,2-di-[(9Z)-octadec-9-enoyl]-sn-glycero-3-phosphoethanolamine (DOPE) (1/2, n/n) exhibits effective pDNA transfer in three different cell lines, namely Hep-G2, A549, and COS-7. The presence of 10% serum during lipoplex incubation of the cells did not affect the transfection efficiency. Based on that, detailed investigations of the complexation of pDNA with the lipid formulation T14diLys/DOPE 1/2 (n/n) were carried out with respect to particle size and charge using dynamic light scattering (DLS), ζ-potential measurements, and transmission electron microscopy (TEM). Additionally, the lipoplex uptake was investigated by confocal laser scanning microscopy (CLSM). Overall, lipoplexes prepared from T14diLys/DOPE 1/2 (n/n) offer large potential as lipid-based polynucleotide carriers and further justify advanced examinations. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Threonine supplementation reduces dietary protein and improves lipid metabolism in Pekin ducks.

    Science.gov (United States)

    Jiang, Y; Tang, J; Xie, M; Wen, Z G; Qiao, S Y; Hou, S S

    2017-12-01

    1. This study was conducted to investigate the efficiency of threonine (Thr) supplementation on reducing dietary crude protein (CP) content and the effects of Thr on lipid metabolism in Pekin ducks. The effects of dietary CP concentration (160, 190 and 220 g/kg) and Thr supplemental concentration (0, 0.7, 1.4, 2.1 and 2.8 g/kg) on growth performance, carcass, liver lipid and plasma profiles were determined in Pekin ducks from 1-21 d of age. 2. A total of 720-d-old male Pekin ducks were randomly allotted to 1 of 15 dietary treatments with 6 replicate cages of 8 birds per cage for each treatment according to average body weight. 3. Dietary Thr supplementation improved growth performance and breast muscle percentage at all CP diets, and ducks fed Thr-supplemented diets had higher plasma concentrations of some plasma amino acids. Thr supplementation reduced the concentrations of total lipid, triglyceride, cholesterol in liver, and plasma low density lipoprotein cholesterin concentration at 160 and 190 g/kg CP, whereas it increased triglyceride concentration at 160 g/kg CP. 4. Thr requirements based on quadratic broken-line model estimation were 6.6 and 7.0 g/kg for optimal average daily gain (ADG), and 6.7 and 7.3 g/kg for breast muscle percentage of Pekin ducks from 1-21 d of age at 190 and 220 g/kg CP, respectively. The dietary Thr requirements and estimated ADG (55.18 vs. 55.86 g/d/bird) and breast muscle percentage (2.79% vs. 2.75%) of Pekin ducks did not differ between 190 and 220 g/kg CP according to the t-test results. 5. Dietary CP level could be reduced to 190 g/kg in Pekin ducks from 1-21 d of age with Thr supplementation to balance dietary amino acids, and Thr supplementation prevented excess liver lipid deposition in this instance.

  8. Comparative study of lipids in mature seeds of six Cordia species (family Boraginaceae) collected in different regions of Brazil.

    Science.gov (United States)

    Carvalho, Patricía de O; Arrebola, Melissa B; Sawaya, Alexandra C H F; Cunha, Ildenize B S; Bastos, Deborah H M; Eberlin, Marcos N

    2006-08-01

    The oil content, FA, and lipid class composition of the mature seeds of six Cordia species were analyzed. Mature seeds of each species were collected in their natural habitat from 2002 to 2004. The total lipid content varied from 1.9% to 13.2%, there being significant differences between the results found in different years for each species and between the species analyzed. The contents of FFA varied from 2.0% to 7.9% of total lipids. Neutral lipids (NL) were the largest class, making up between 89.6% and 96.4% of the total lipids; the phospholipids (PL) were the second largest class (3.0% to 8.9% of the total lipids), and the glycolipids (GL) were the smallest class (0.6 to 3.4%). The presence of GLA was determined in each class of lipids; it is predominant in the NL. Levels of GLA ranged from 1.2% to 6.8% of total seed FA. This is, to our knowledge the first study of lipid composition in seeds of species of Cordia from Brazil.

  9. Lipid metabolism in cancer cachexia.

    OpenAIRE

    Mulligan, H. D.; Beck, S. A.; Tisdale, M. J.

    1992-01-01

    The effect of cancer cachexia on the oxidative metabolism of lipids has been studied in mice transplanted either with the MAC16 adenocarcinoma, which induces profound loss of body weight and depletion of lipid stores, or the MAC13 adenocarcinoma, which is the same histological type, but which grows without an effect on host body weight or lipid stores. While oxidation of D-[U-14C]glucose did not differ between animals bearing tumours of either type and non-tumour bearing controls, oxidation o...

  10. Effects of atmospheric pollutants on lipids

    International Nuclear Information System (INIS)

    Howton, D.R.

    1976-01-01

    Studies on effects of atmospheric pollutants on lipids emphasized effects of nitrogen dioxide on olefinic centers of alveolar fluid surfactant lipids. The finding that NO 2 attacks α-tocopherol much more avidly than olefinic fatty esters indicates that the autoxidation enhancing effects of this atmospheric pollutant may be greatly magnified by destruction of native antioxidants that normally suppress the extensiveness of such lipid oxidation

  11. Red wine tannins fluidify and precipitate lipid liposomes and bicelles. A role for lipids in wine tasting?

    Science.gov (United States)

    Furlan, Aurélien L; Castets, Aurore; Nallet, Frédéric; Pianet, Isabelle; Grélard, Axelle; Dufourc, Erick J; Géan, Julie

    2014-05-20

    Sensory properties of red wine tannins are bound to complex interactions between saliva proteins, membranes taste receptors of the oral cavity, and lipids or proteins from the human diet. Whereas astringency has been widely studied in terms of tannin-saliva protein colloidal complexes, little is known about interactions between tannins and lipids and their implications in the taste of wine. This study deals with tannin-lipid interactions, by mimicking both oral cavity membranes by micrometric size liposomes and lipid droplets in food by nanometric isotropic bicelles. Deuterium and phosphorus solid-state NMR demonstrated the membrane hydrophobic core disordering promoted by catechin (C), epicatechin (EC), and epigallocatechin gallate (EGCG), the latter appearing more efficient. C and EGCG destabilize isotropic bicelles and convert them into an inverted hexagonal phase. Tannins are shown to be located at the membrane interface and stabilize the lamellar phases. These newly found properties point out the importance of lipids in the complex interactions that happen in the mouth during organoleptic feeling when ingesting tannins.

  12. Variability of nutrients intake, lipid profile and cardiovascular mortality among geographical areas in Spain: The DRECE study.

    Science.gov (United States)

    Gómez de la Cámara, Agustín; De Andrés Esteban, Eva; Urrútia Cuchí, Gerard; Calderón Sandubete, Enrique; Rubio Herrera, Miguel Ángel; Menéndez Orenga, Miguel; Lora Pablos, David

    2017-11-07

    It has often been suggested that cardiovascular mortality and their geographical heterogeneity are associated with nutrients intake patterns and also lipid profile. The large Spanish study Dieta y Riesgo de Enfermedades Cardiovasculares en España (DRECE) investigated this theory from 1991 to 2010. Out of the 4,783 Spanish individuals making up the DRECE cohort, 220 subjects (148 men and 72 women) died (4.62%) during the course of the study. The mean age of patients who died from cardiovascular causes (32 in all) was 61.08 years 95% CI (57.47-64.69) and 70.91% of them were males. The consumption of nutrients and the lipid profile by geographical area, studied by geospatial models, showed that the east and southern area of the country had the highest fat intake coupled to a high rate of unhealthy lipid profile. It was concluded that the spatial geographical analysis showed a relationship between high fat intake, unhealthy lipid profile and cardiovascular mortality in the different geographical areas, with a high variability within the country.

  13. Lipids, lipid genes, and incident age-related macular degeneration: the three continent age-related macular degeneration consortium

    NARCIS (Netherlands)

    Klein, Ronald; Myers, Chelsea E.; Buitendijk, Gabriëlle H. S.; Rochtchina, Elena; Gao, Xiaoyi; de Jong, Paulus T. V. M.; Sivakumaran, Theru A.; Burlutsky, George; McKean-Cowdin, Roberta; Hofman, Albert; Iyengar, Sudha K.; Lee, Kristine E.; Stricker, Bruno H.; Vingerling, Johannes R.; Mitchell, Paul; Klein, Barbara E. K.; Klaver, Caroline C. W.; Wang, Jie Jin

    2014-01-01

    To describe associations of serum lipid levels and lipid pathway genes to the incidence of age-related macular degeneration (AMD). Meta-analysis. setting: Three population-based cohorts. population: A total of 6950 participants from the Beaver Dam Eye Study (BDES), Blue Mountains Eye Study (BMES),

  14. Solid Lipid Nanoparticles of Guggul Lipid as Drug Carrier for Transdermal Drug Delivery

    Directory of Open Access Journals (Sweden)

    Praveen Kumar Gaur

    2013-01-01

    Full Text Available Diclofenac sodium loaded solid lipid nanoparticles (SLNs were formulated using guggul lipid as major lipid component and analyzed for physical parameters, permeation profile, and anti-inflammatory activity. The SLNs were prepared using melt-emulsion sonication/low temperature-solidification method and characterized for physical parameters, in vitro drug release, and accelerated stability studies, and formulated into gel. Respective gels were compared with a commercial emulgel (CEG and plain carbopol gel containing drug (CG for ex vivo and in vivo drug permeation and anti-inflammatory activity. The SLNs were stable with optimum physical parameters. GMS nanoparticle 1 (GMN-1 and stearic acid nanoparticle 1 (SAN-1 gave the highest in vitro drug release. Guggul lipid nanoparticle gel 3 (GLNG-3 showed 104.68 times higher drug content than CEG in receptor fluid. The enhancement ratio of GLNG-3 was 39.43 with respect to CG. GLNG-3 showed almost 8.12 times higher Cmax than CEG at 4 hours. The AUC value of GLNG-3 was 15.28 times higher than the AUC of CEG. GLNG-3 showed edema inhibition up to 69.47% in the first hour. Physicochemical properties of major lipid component govern the properties of SLN. SLN made up of guggul lipid showed good physical properties with acceptable stability. Furthermore, it showed a controlled drug release profile along with a promising permeation profile.

  15. Computer Simulations of Lipid Nanoparticles

    Directory of Open Access Journals (Sweden)

    Xavier F. Fernandez-Luengo

    2017-12-01

    Full Text Available Lipid nanoparticles (LNP are promising soft matter nanomaterials for drug delivery applications. In spite of their interest, little is known about the supramolecular organization of the components of these self-assembled nanoparticles. Here, we present a molecular dynamics simulation study, employing the Martini coarse-grain forcefield, of self-assembled LNPs made by tripalmitin lipid in water. We also study the adsorption of Tween 20 surfactant as a protective layer on top of the LNP. We show that, at 310 K (the temperature of interest in biological applications, the structure of the lipid nanoparticles is similar to that of a liquid droplet, in which the lipids show no nanostructuration and have high mobility. We show that, for large enough nanoparticles, the hydrophilic headgroups develop an interior surface in the NP core that stores liquid water. The surfactant is shown to organize in an inhomogeneous way at the LNP surface, with patches with high surfactant concentrations and surface patches not covered by surfactant.

  16. Characterization of Carbamazepine-Loaded Solid Lipid ...

    African Journals Online (AJOL)

    loaded solid lipid nanoparticles by RESS as well as their characterization has been achieved in this study. Keywords: Rapid expansion of supercritical fluid, Stearic acid, Solid lipid nanoparticles, Carbamazepine, Co-precipitation ...

  17. Molecular dynamics study of homo-oligomeric ion channels: Structures of the surrounding lipids and dynamics of water movement

    Directory of Open Access Journals (Sweden)

    Thuy Hien Nguyen

    2018-03-01

    Full Text Available Molecular dynamics simulations were used to study the structural perturbations of lipids surrounding transmembrane ion channel forming helices/helical bundles and the movement of water within the pores of the ion-channels/bundles. Specifically, helical monomers to hexameric helical bundles embedded in palmitoyl-oleoyl-phosphatidyl-choline (POPC lipid bilayer were studied. Two amphipathic α-helices with the sequence Ac-(LSLLLSL3-NH2 (LS2, and Ac-(LSSLLSL3-NH2 (LS3, which are known to form ion channels, were used. To investigate the surrounding lipid environment, we examined the hydrophobic mismatch, acyl chain order parameter profiles, lipid head-to-tail vector projection on the membrane surface, and the lipid headgroup vector projection. We find that the lipid structure is perturbed within approximately two lipid solvation shells from the protein bundle for each system (~15.0 Å. Beyond two lipid “solvation” shells bulk lipid bilayer properties were observed in all systems. To understand water flow, we enumerated each time a water molecule enters or exited the channel, which allowed us to calculate the number of water crossing events and their rates, and the residence time of water in the channel. We correlate the rate of water crossing with the structural properties of these ion channels and find that the movements of water are predominantly governed by the packing and pore diameter, rather than the topology of each peptide or the pore (hydrophobic or hydrophilic. We show that the crossing events of water fit quantitatively to a stochastic process and that water molecules are traveling diffusively through the pores. These lipid and water findings can be used for understanding the environment within and around ion channels. Furthermore, these findings can benefit various research areas such as rational design of novel therapeutics, in which the drug interacts with membranes and transmembrane proteins to enhance the efficacy or reduce off

  18. Lipid Production of Heterotrophic Chlorella sp. from Hydrolysate Mixtures of Lipid-Extracted Microalgal Biomass Residues and Molasses.

    Science.gov (United States)

    Zheng, Hongli; Ma, Xiaochen; Gao, Zhen; Wan, Yiqin; Min, Min; Zhou, Wenguang; Li, Yun; Liu, Yuhuan; Huang, He; Chen, Paul; Ruan, Roger

    2015-10-01

    This study investigated the feasibility of lipid production of Chlorella sp. from waste materials. Lipid-extracted microalgal biomass residues (LMBRs) and molasses were hydrolyzed, and their hydrolysates were analyzed. Five different hydrolysate mixture ratios (w/w) of LMBRs/molasses (1/0, 1/1, 1/4, 1/9, and 0/1) were used to cultivate Chlorella sp. The results showed that carbohydrate and protein were the two main compounds in the LMBRs, and carbohydrate was the main compound in the molasses. The highest biomass concentration of 5.58 g/L, Y biomass/sugars of 0.59 g/g, lipid productivity of 335 mg/L/day, and Y lipids/sugars of 0.25 g/g were obtained at the hydrolysate mixture ratio of LMBRs/molasses of 1/4. High C/N ratio promoted the conversion of sugars into lipids. The lipids extracted from Chlorella sp. shared similar lipid profile of soybean oil and is therefore a potential viable biodiesel feedstock. These results showed that Chlorella sp. can utilize mixed sugars and amino acids from LMBRs and molasses to accumulate lipids efficiently, thus reducing the cost of microalgal biodiesel production and improving its economic viability.

  19. ATR-IR study of skin components: Lipids, proteins and water. Part I: Temperature effect

    Science.gov (United States)

    Olsztyńska-Janus, S.; Pietruszka, A.; Kiełbowicz, Z.; Czarnecki, M. A.

    2018-01-01

    In this work we report the studies of the effect of temperature on skin components, such as lipids, proteins and water. Modifications of lipids structure induced by increasing temperature (from 20 to 90 °C) have been studied using ATR-IR (Attenuated Total Reflectance Infrared) spectroscopy, which is a powerful tool for characterization of the molecular structure and properties of tissues, such as skin. Due to the small depth of penetration (0.6-5.6 μm), ATR-IR spectroscopy probes only the outermost layer of the skin, i.e. the stratum corneum (SC). The assignment of main spectral features of skin components allows for the determination of phase transitions from the temperature dependencies of band intensities [e.g. νas(CH2) and νs(CH2)]. The phase transitions were determined by using two methods: the first one was based on the first derivative of the Boltzmann function and the second one employed tangent lines of sigmoidal, aforementioned dependencies. The phase transitions in lipids were correlated with modifications of the structure of water and proteins.

  20. Lipid clustering correlates with membrane curvature as revealed by molecular simulations of complex lipid bilayers.

    Directory of Open Access Journals (Sweden)

    Heidi Koldsø

    2014-10-01

    Full Text Available Cell membranes are complex multicomponent systems, which are highly heterogeneous in the lipid distribution and composition. To date, most molecular simulations have focussed on relatively simple lipid compositions, helping to inform our understanding of in vitro experimental studies. Here we describe on simulations of complex asymmetric plasma membrane model, which contains seven different lipids species including the glycolipid GM3 in the outer leaflet and the anionic lipid, phosphatidylinositol 4,5-bisphophate (PIP2, in the inner leaflet. Plasma membrane models consisting of 1500 lipids and resembling the in vivo composition were constructed and simulations were run for 5 µs. In these simulations the most striking feature was the formation of nano-clusters of GM3 within the outer leaflet. In simulations of protein interactions within a plasma membrane model, GM3, PIP2, and cholesterol all formed favorable interactions with the model α-helical protein. A larger scale simulation of a model plasma membrane containing 6000 lipid molecules revealed correlations between curvature of the bilayer surface and clustering of lipid molecules. In particular, the concave (when viewed from the extracellular side regions of the bilayer surface were locally enriched in GM3. In summary, these simulations explore the nanoscale dynamics of model bilayers which mimic the in vivo lipid composition of mammalian plasma membranes, revealing emergent nanoscale membrane organization which may be coupled both to fluctuations in local membrane geometry and to interactions with proteins.

  1. Effects of extremely low frequency electromagnetic fields on paraoxonase serum activity and lipid peroxidation metabolites in rat.

    Science.gov (United States)

    Seifirad, Soroush; Farzampour, Shahrokh; Nourbakhsh, Mitra; Amoli, Mahsa Mohammad; Razzaghy-Azar, Maryam; Larijani, Bagher

    2014-01-01

    Atherogenic effects of ELF-MF exposure have not been studied well so far. Therefore we have hypothesized that ELF-MF exposure might have atherogenic effect by impairing antioxidant function and increasing lipid peroxidation. This study was therefore undertaken to examine the effects of ELF-MF on paraoxonase (PON) activity, antioxidant capacity and lipid peroxidation metabolites. Effects of time on remodeling of antioxidant system were also investigated in this study. Seventy five Wistar rats were randomly allocated into five groups as follows: 1) Sham exposure, 2) Single exposure to 60 Hz, sacrificed immediately after exposure, 3) Single exposure to 60 Hz, sacrificed 72 hours after exposure, 4) Fourteen days of exposure to 60 Hz, sacrificed immediately after exposure, and 5) Fourteen days of exposure to 60 Hz, sacrificed 72 hours after exposure. Blood samples were collected and analyzed. The results were compared using ANOVA and post hoc Tukey HSD for multiple caparisons. Single ELF-MF exposure significantly increased lipid peroxidation (CD and MDA) and increased antioxidant serum activity (HDL, paraoxonase activity, and serum total antioxidant capacity). Chronic ELF-MF exposure increased lipid peroxidation and affected antioxidant system. Free fatty acids levels were significantly increased after both single and two weeks exposure. Chronic exposure led to irreversible changes while acute exposure tended to reversible alterations on above mentioned parameters. According to the results of this study, ELF-MF exposure could impair oxidant-antioxidant function and might increase oxidative stress and lipid peroxidation. Antioxidant capability was dependent on the duration and continuity of ELF-MF exposure.

  2. Phosphoethanolamine Modification of Neisseria gonorrhoeae Lipid A Reduces Autophagy Flux in Macrophages.

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    Susu M Zughaier

    Full Text Available Autophagy, an ancient homeostasis mechanism for macromolecule degradation, performs an important role in host defense by facilitating pathogen elimination. To counteract this host defense strategy, bacterial pathogens have evolved a variety of mechanisms to avoid or otherwise dysregulate autophagy by phagocytic cells so as to enhance their survival during infection. Neisseria gonorrhoeae is a strictly human pathogen that causes the sexually transmitted infection, gonorrhea. Phosphoethanolamine (PEA addition to the 4' position of the lipid A (PEA-lipid A moiety of the lipooligosaccharide (LOS produced by gonococci performs a critical role in this pathogen's ability to evade innate defenses by conferring decreased susceptibility to cationic antimicrobial (or host-defense peptides, complement-mediated killing by human serum and intraleukocytic killing by human neutrophils compared to strains lacking this PEA decoration. Heretofore, however, it was not known if gonococci can evade autophagy and if so, whether PEA-lipid A contributes to this ability. Accordingly, by using murine macrophages and human macrophage-like phagocytic cell lines we investigated if PEA decoration of gonococcal lipid A modulates autophagy formation. We report that infection with PEA-lipid A-producing gonococci significantly reduced autophagy flux in murine and human macrophages and enhanced gonococcal survival during their association with macrophages compared to a PEA-deficient lipid A mutant. Our results provide further evidence that PEA-lipid A produced by gonococci is a critical component in the ability of this human pathogen to evade host defenses.

  3. Effects of Dietary Protein and Lipid Levels on Growth and Body Composition of Juvenile Far Eastern Catfish

    Directory of Open Access Journals (Sweden)

    Kyoung-Duck Kim

    2012-03-01

    Full Text Available A 3×2 factorial experiment was conducted to determine the effects of dietary protein and lipid levels on the growth and body composition of juvenile far eastern catfish. Six diets were formulated to contain three levels of protein (20%, 30% and 40% and two levels of lipid (9% and 17%. Triplicate groups of fish (initial body weight of 7.6 g were hand-fed to apparent satiation for 66 days. Final mean weight was improved with increasing dietary protein and lipid levels, and the highest final mean weight was observed in fish fed the 40/17 (% protein/% lipid diet. No significant difference was observed in final mean weight for fish fed between 30/17 diet and 40/9 diet. Feed efficiency of fish fed the diets containing over 30% protein levels with 9% and 17% lipid levels were significantly higher than those of fish fed the 20% protein levels. Feed efficiency of fish fed the 30/17 diet was not significantly different from that of fish fed the 40/9 diet or 40/17 diet. Feed efficiency and protein efficiency ratio of fish fed the 20% protein diets with 17% lipid level were significantly higher than those of fish fed 9% lipid diet. Daily feed intake of fish tended to decrease with increasing dietary protein and lipid levels. Moisture content of whole body in fish fed the 9% lipid diets was significantly higher than that of fish fed the 17% lipid diets at the same protein level, but the opposite trends were found for crude lipid content. Significant effects of dietary lipid were observed for most fatty acids, according to their relative values in the diets. The results of this study suggest that the protein requirement for maximum growth of juvenile far eastern catfish may be higher than 40%, and an increase of dietary lipid level from 9% to 17% can improve growth and feed utilization.

  4. Nanostructured lipid carriers (NLCs) versus solid lipid nanoparticles (SLNs) for topical delivery of meloxicam.

    Science.gov (United States)

    Khalil, Rawia M; Abd-Elbary, A; Kassem, Mahfoz A; Ghorab, Mamdouh M; Basha, Mona

    2014-05-01

    The aim of this study was to develop nanostructured lipid carriers (NLCs) as well as solid lipid nanoparticles (SLNs) and evaluate their potential in the topical delivery of meloxicam (MLX). The effect of various compositional variations on their physicochemical properties was investigated. Furthermore, MLX-loaded lipid nanoparticles-based hydrogels were formulated and the gels were evaluated as vehicles for topical application. The results showed that NLC and SLN dispersions had spherical shapes with an average size between 215 and 430 nm. High entrapment efficiency was obtained ranging from 61.94 to 90.38% with negatively charged zeta potential in the range of -19.1 to -25.7 mV. The release profiles of all formulations exhibited sustained release characteristics over 48 h and the release rates increased as the amount of liquid lipid in lipid core increased. Finally, Precirol NLC with 50% Miglyol® 812 and its corresponding SLN were incorporated in hydrogels. The gels showed adequate pH, non-Newtonian flow with shear-thinning behavior and controlled release profiles. The biological evaluation revealed that MLX-loaded NLC gel showed more pronounced effect compared to MLX-loaded SLN gel. It can be concluded that lipid nanoparticles represent promising particulate carriers for topical application.

  5. Preparation and Characterization of Minoxidil Loaded Nanostructured Lipid Carriers.

    Science.gov (United States)

    Wang, Wenxi; Chen, Lina; Huang, Xinyan; Shao, Anna

    2017-02-01

    Nanostructured lipid carriers (NLCs) are interesting delivery systems for enhancing the penetration of an active substance through the skin after topical administration. The present paper described the development of a novel NLCs for minoxidil (MXD) topical delivery. Stearic acid and oleic acid that showed the highest solubility for MXD were selected as solid lipid and liquid lipid, respectively, and the NLCs were prepared by hot high pressure homogenization method. The minoxidil loaded NLCs prepared accordingly to the optimal formulation exhibited spherical shape with a mean diameter of 281.4 ± 7.4 nm, polydispersity of 0.207 ± 0.009, zeta potential of -32.90 ± 1.23 mV, drug entrapment efficiency of 92.48 ± 0.31%, and drug loading of 13.85 ± 0.47%. Storage stability studies demonstrated that the particle size and entrapment efficiency of the MXD-NLCs were not changed during 3 months both at 4°C and room temperature. Moreover, the release of MXD from the NLCs was faster than drug release from SLNs. In vitro skin permeability test demonstrated that MXD-NLCs had a more pronounced permeation and retention profile than MXD-SLNs. Furthermore, no erythema was observed after administration of MXD-NLCs. All these results indicated that the developed MXD-NLCs could be a promising and effective nanocarrier for topical delivery of MXD.

  6. Hydration dynamics of a lipid membrane: Hydrogen bond networks and lipid-lipid associations

    Science.gov (United States)

    Srivastava, Abhinav; Debnath, Ananya

    2018-03-01

    Dynamics of hydration layers of a dimyristoylphosphatidylcholine (DMPC) bilayer are investigated using an all atom molecular dynamics simulation. Based upon the geometric criteria, continuously residing interface water molecules which form hydrogen bonds solely among themselves and then concertedly hydrogen bonded to carbonyl, phosphate, and glycerol head groups of DMPC are identified. The interface water hydrogen bonded to lipids shows slower relaxation rates for translational and rotational dynamics compared to that of the bulk water and is found to follow sub-diffusive and non-diffusive behaviors, respectively. The mean square displacements and the reorientational auto-correlation functions are slowest for the interfacial waters hydrogen bonded to the carbonyl oxygen since these are buried deep in the hydrophobic core among all interfacial water studied. The intermittent hydrogen bond auto-correlation functions are calculated, which allows breaking and reformations of the hydrogen bonds. The auto-correlation functions for interfacial hydrogen bonded networks develop humps during a transition from cage-like motion to eventual power law behavior of t-3/2. The asymptotic t-3/2 behavior indicates translational diffusion dictated dynamics during hydrogen bond breaking and formation irrespective of the nature of the chemical confinement. Employing reactive flux correlation analysis, the forward rate constant of hydrogen bond breaking and formation is calculated which is used to obtain Gibbs energy of activation of the hydrogen bond breaking. The relaxation rates of the networks buried in the hydrophobic core are slower than the networks near the lipid-water interface which is again slower than bulk due to the higher Gibbs energy of activation. Since hydrogen bond breakage follows a translational diffusion dictated mechanism, chemically confined hydrogen bond networks need an activation energy to diffuse through water depleted hydrophobic environments. Our calculations

  7. TIME COURSE OF CHANGES IN BLOOD LIPID PARAMETERS IN PATIENTS WITH EARLY RHEUMATOID ARTHRITIS DURING TREAT-TO-TARGET ANTIRHEUMATIC THERAPY: ACCORDING TO 18-MONTH FOLLOW-UP FINDINGS

    Directory of Open Access Journals (Sweden)

    E. V. Udachkina

    2016-01-01

    Full Text Available The mechanisms for lowering a cardiovascular risk (CVR in patients with early rheumatoid arthritis (RA when implementing the treat-to-target strategy remain inadequately investigated.Objective: to estimate the time course of changes in blood lipid parameters in patients with early RA during Treat-totarget antirheumatic therapy at an 18-month follow-up.Subjects and methods. Seventy-four patients (73% women; median age, 56 years with early RA meeting the respective 2010 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR classification criteria and moderate or high activity (median DAS28-ESR score of 5.4 were examined within the framework of the REMARCA trial. After 6-month treatment, RA activity significantly reduced (p < 0.05. At months 6 to 18, no significant change in RA activity was recorded. After 18 months, remission was observed in 31 (42% patients: in 17 (55% on methotrexate (MTX monotherapy and in 14 (45% on combined therapy with MTX and a biological agent. Blood lipid levels were determined at inclusion in the investigation, 6 and 18 months later. The values of lipid parameters were estimated in terms of the total CVR. 67.6% of the patients were classified as at very high CVR. At 18 months of treatment, 34 (46% patients were treated with statins (median atorvastatin and rosuvastatin doses were 10 mg/day each.Results and discussion. Only 12% of the patients had optimal baseline values of just all lipid parameters. The concentration of total cholesterol (TC, low-density lipoprotein cholesterol (LDL-C, and high-density lipoprotein cholesterol (HDL-C correlated negatively with C-reactive protein (CRP levels, DAS28-ESR, DAS28-CRP, and HAQ (p < 0.05. After 6-month treatment, there were increases in TC by 7%, LDL-C by 12.5%, and HDL-C by 19.7%, and a decrease in the atherogenic index by 16% (p < 0.05. ΔCRP negatively correlated with ΔTC, ΔLDL-C, and ΔHDL-C (r = -0.3; p < 0.05. A correlation of TC and LDL-C with

  8. Dermal extracellular lipid in birds.

    Science.gov (United States)

    Stromberg, M W; Hinsman, E J; Hullinger, R L

    1990-01-01

    A light and electron microscopic study of the skin of domestic chickens, seagulls, and antarctic penguins revealed abundant extracellular dermal lipid and intracellular epidermal lipid. Dermal lipid appeared ultrastructurally as extracellular droplets varying from less than 1 micron to more than 25 microns in diameter. The droplets were often irregularly contoured, sometimes round, and of relatively low electron density. Processes of fibrocytes were often seen in contact with extracellular lipid droplets. Sometimes a portion of such a droplet was missing, and this missing part appeared to have been "digested away" by the cell process. In places where cells or cell processes are in contact with fact droplets, there are sometimes extracellular membranous whorls or fragments which have been associated with the presence of fatty acids. Occasionally (in the comb) free fat particles were seen in intimate contact with extravasated erythrocytes. Fat droplets were seen in the lumen of small dermal blood and lymph vessels. We suggest that the dermal extracellular lipid originates in the adipocyte layer and following hydrolysis the free fatty acids diffuse into the epidermis. Here they become the raw material for forming the abundant neutral lipid contained in many of the epidermal cells of both birds and dolphins. The heretofore unreported presence and apparently normal utilization of abundant extracellular lipid in birds, as well as the presence of relatively large droplets of neutral lipid in dermal vessels, pose questions which require a thorough reappraisal of present concepts of the ways in which fat is distributed and utilized in the body.

  9. Lipidic profile and the level of physical activity of adolescent scholars - doi:10.5020/18061230.2011.p384

    Directory of Open Access Journals (Sweden)

    Renato Canevari Dutra da Silva

    2012-01-01

    Full Text Available Objective: To assess the relationship between lipid profile and physical activity level of adolescent students in Rio Verde-GO, Brazil. Methods: A descriptive and cross-sectional study, conducted in 2006, with a population comprised by 1,229 adolescent students of both genders, aged 15 to 17 years (X = 15.9 years, SD + 0.81, from public and private schools. The level of physical activity was assessed through the International Physical Activity Questionnaire (IPAQ. Later, 48 teenagers underwent a lipidogram (lipid profile. Lipid concentrations of total cholesterol (TC, HDL-c (high density lipoprotein and LDL (low density lipoprotein and triglycerides (TGL were determined and assessed according to cutoff points proposed by the III Brazilian Guidelines on dyslipidemias and Guideline of Atherosclerosis, Department of Atherosclerosis of Brazilian Society of Cardiology. Statistical analysis was performed by binomial test for proportions and Pearson’s correlation test, adopting p <0.05. Results: Applying IPAQ we found apercentage of 77.7% active adolescents and 22.3% of insufficiently active adolescents, with the highest percentage of active teens in males (p = 0.0000. Adolescents of both sexes from public network were considered more active than teens from private schools. The lipid profile of the studied adolescents was within normal range. Conclusion: There was no relationship between physical activity level and lipid profile of the adolescents assessed.

  10. Solubilization and localization of weakly polar lipids in unsonicated egg phosphatidylcholine: A 13C MAS NMR study

    International Nuclear Information System (INIS)

    Hamilton, J.A.; Fujito, D.T.; Hammer, C.F.

    1991-01-01

    The weakly polar lipids cholesteryl ester, triacylglycerol, and diacylglycerol incorporate to a limited extent into the lamellar structure of small unilamellar vesicles. The localization of the carbonyl group(s) at the aqueous interface was detected by [ 13 C]carbonyl chemical shift changes relative to the neat unhydrated lipid. This study uses 13 C NMR to investigate the interactions of thes lipids with unsonicated (multilamellar) phosphatidylcholine, a model system for cellular membranes and surfaces of emulsion particles with low curvature. Magic angle spinning reduced the broad lines of the unsonicated dispersions to narrow lines comparable to those from sonicated dispersions. [ 13 C]Carbonyl chemical shifts revealed incorporation of the three lipids into the lamellar structure of the unsonicated phospholipids and a partial hydration of the carbonyl groups similar to that observed in small vesicles. Other properties of interfacial weakly polar lipids in multilayers were similar to those in small unilamellar bilayers. There is thus a general tendency of weakly polar lipids to incorparate at least to a small extent into the lamellar structure of phospholipids and take on interfacial properties that are distinct from their bulk-phase properties. This pool of surface-located lipid is likely to be directly involved in enzymatyic transformations and protein-mediated transport. The 13 C magic angle spinning NMR method may be generally useful for determining the orientation of molecules in model membranes

  11. Phloem proteomics reveals new lipid-binding proteins with a putative role in lipid-mediated signaling

    Directory of Open Access Journals (Sweden)

    Allison Marie Barbaglia

    2016-04-01

    Full Text Available Global climate changes inversely affect our ability to grow the food required for an increasing world population. To combat future crop loss due to abiotic stress, we need to understand the signals responsible for changes in plant development and the resulting adaptations, especially the signaling molecules traveling long-distance through the plant phloem. Using a proteomics approach, we had identified several putative lipid-binding proteins in the phloem exudates. Simultaneously, we identified several complex lipids as well as jasmonates. These findings prompted us to propose that phloem (phospho- lipids could act as long-distance developmental signals in response to abiotic stress, and that they are released, sensed, and moved by phloem lipid-binding proteins (Benning et al., 2012. Indeed, the proteins we identified include lipases that could release a signaling lipid into the phloem, putative receptor components, and proteins that could mediate lipid-movement. To test this possible protein-based lipid-signaling pathway, three of the proteins, which could potentially act in a relay, are characterized here: (I a putative GDSL-motif lipase (II a PIG-P-like protein, with a possible receptor-like function; (III and PLAFP (phloem lipid-associated family protein, a predicted lipid-binding protein of unknown function. Here we show that all three proteins bind lipids, in particular phosphatidic acid (PtdOH, which is known to participate in intracellular stress signaling. Genes encoding these proteins are expressed in the vasculature, a prerequisite for phloem transport. Cellular localization studies show that the proteins are not retained in the endoplasmic reticulum but surround the cell in a spotted pattern that has been previously observed with receptors and plasmodesmatal proteins. Abiotic signals that induce the production of PtdOH also regulate the expression of GDSL-lipase and PLAFP, albeit in opposite patterns. Our findings suggest that while

  12. Computer Simulations of Lipid Bilayers and Proteins

    DEFF Research Database (Denmark)

    Sonne, Jacob

    2006-01-01

    The importance of computer simulations in lipid bilayer research has become more prominent for the last couple of decades and as computers get even faster, simulations will play an increasingly important part of understanding the processes that take place in and across cell membranes. This thesis...... entitled Computer simulations of lipid bilayers and proteins describes two molecular dynamics (MD) simulation studies of pure lipid bilayers as well as a study of a transmembrane protein embedded in a lipid bilayer matrix. Below follows a brief overview of the thesis. Chapter 1. This chapter is a short...... in the succeeding chapters is presented. Details on system setups, simulation parameters and other technicalities can be found in the relevant chapters. Chapter 3, DPPC lipid parameters: The quality of MD simulations is intimately dependent on the empirical potential energy function and its parameters, i...

  13. Effects of postmenopausal hormone therapy every day and every other day on lipid levels according to difference in body mass index.

    Science.gov (United States)

    Yasui, Toshiyuki; Umino, Yuka; Takikawa, Masaya; Uemura, Hirokazu; Kuwahara, Akira; Matsuzaki, Toshiya; Maegawa, Masahiko; Furumoto, Hiroyuki; Miura, Masakazu; Irahara, Minoru

    2005-03-01

    The objective of this study was to determine the effects of postmenopausal estrogen and progestogen therapy (EPT) every day and every other day on lipid levels, particularly triglyceride (TG) levels, according to difference in body mass index (BMI). Ninety-nine postmenopausal women (mean age, 53.9 +/- 5.6 years; mean BMI, 22.8 +/- 2.8 kg/m) were randomly treated with EPT every other day or every day for 1 year. Fifty women received oral administration of 0.625 mg of conjugated equine estrogen (CEE) and 2.5 mg of medroxyprogesterone acetate (MPA) every other day, and 49 women received oral administration of 0.625 mg of CEE and 2.5 mg of MPA every day. Blood samples were collected at baseline and after 1 year of therapy for measurement of fasting TG, total cholesterol, high-density lipoprotein-cholesterol (HDL-C), and apolipoproteins. Data from 88 of the 99 postmenopausal women were used for analysis. In women whose BMI was 25 kg/m or higher, TG levels during EPT every day increased by 26.8%, while TG levels during EPT every other day decreased by 12.3%. There was a significant (P every day and every other day. In women whose BMI was less than 25 kg/m, TG levels during EPT every day increased by 21.7%, while during EPT every other day TG levels did not change. The mean levels of estradiol during EPT every day in women whose BMI was less than 25 kg/m and in women whose BMI was 25 kg/m or higher were 28.5 and 38.7 pg/mL, respectively, the difference between these levels was significant (P every other day in these two BMI groups. Triglyceride levels during EPT every day with conventional doses of CEE and MPA increased more in overweight and obese postmenopausal women in association with increased estrogen levels.

  14. Effects of Ferulago angulata Extract on Serum Lipids and Lipid Peroxidation

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    Mahmoud Rafieian-kopaei

    2014-01-01

    Full Text Available Background. Nowadays, herbs they are considered to be the main source of effective drugs for lowering serum lipids and lipid peroxidation. The present experimental animal study aimed to assess the impact of Ferulago angulata on serum lipid profiles, and on levels of lipid peroxidation. Methods. Fifty male Wistar rats, weighing 250–300 g, were randomly divided into five equal groups (ten rats in each. The rat groups received different diets as follows: Group I: fat-rich diet; Group II: fat-rich diet plus hydroalcoholic extracts of Ferulago angulata at a dose of 400 mg/kg; Group III: fat-rich diet plus hydroalcoholic extracts of Ferulago angulata at a dose of 600 mg/kg; Group IV: fat-rich diet plus atorvastatin; Group V: common stock diet. The levels of serum glucose and lipids and the atherogenic index were measured. In addition, malondialdehyde (MDA, thiol oxidation, carbonyl concentrations, C-reactive proteins, and antioxidant capacity were evaluated in each group of rats. Results. Interestingly, by adding a hydroalcoholic extract of Ferulago angulata to the high-fat diet, the levels of total cholesterol and low-density lipoproteins (LDL in the high-fat diet rats were both significantly reduced. This result was considerably greater compared to when atorvastatin was added as an antilipid drug. The beneficial effects of the Ferulago angulata extract on lowering the level of triglycerides was observed only when a high dosage of this plant extraction was added to a high fat diet. Furthermore, the level of malondialdehyde, was significantly affected by the use of the plant extract in a high-fat diet, compared with a normal regimen or high-fat diet alone. Conclusion. Administration of a hydroalcoholic extract of Ferulago angulata can reduce serum levels of total cholesterol, triglycerides, and LDL. It can also inhibit lipid peroxidation.

  15. Irregular bilayer structure in vesicles prepared from Halobacterium cutirubrum lipids

    Science.gov (United States)

    Lanyi, J. K.

    1974-01-01

    Fluorescent probes were used to study the structure of the cell envelope of Halobacterium cutirubrum, and, in particular, to explore the effect of the heterogeneity of the lipids in this organism on the structure of the bilayers. The fluorescence polarization of perylene was followed in vesicles of unfractionated lipids and polar lipids as a function of temperature in 3.4 M solutions of NaCl, NaNO3, and KSCN, and it was found that vesicles of unfractionated lipids were more perturbed by chaotropic agents than polar lipids. The dependence of the relaxation times of perylene on temperature was studied in cell envelopes and in vesicles prepared from polar lipids, unfractionated lipids, and mixtures of polar and neutral lipids.

  16. Progesterone lipid nanoparticles: Scaling up and in vivo human study.

    Science.gov (United States)

    Esposito, Elisabetta; Sguizzato, Maddalena; Drechsler, Markus; Mariani, Paolo; Carducci, Federica; Nastruzzi, Claudio; Cortesi, Rita

    2017-10-01

    This investigation describes a scaling up study aimed at producing progesterone containing nanoparticles in a pilot scale. Particularly hot homogenization techniques based on ultrasound homogenization or high pressure homogenization have been employed to produce lipid nanoparticles constituted of tristearin or tristearin in association with caprylic-capric triglyceride. It was found that the high pressure homogenization method enabled to obtain nanoparticles without agglomerates and smaller mean diameters with respect to ultrasound homogenization method. X-ray characterization suggested a lamellar structural organization of both type of nanoparticles. Progesterone encapsulation efficiency was almost 100% in the case of high pressure homogenization method. Shelf life study indicated a double fold stability of progesterone when encapsulated in nanoparticles produced by the high pressure homogenization method. Dialysis and Franz cell methods were performed to mimic subcutaneous and skin administration. Nanoparticles constituted of tristearin in mixture with caprylic/capric triglyceride display a slower release of progesterone with respect to nanoparticles constituted of pure tristearin. Franz cell evidenced a higher progesterone skin uptake in the case of pure tristearin nanoparticles. A human in vivo study, based on tape stripping, was conducted to investigate the performance of nanoparticles as progesterone skin delivery systems. Tape stripping results indicated a decrease of progesterone concentration in stratum corneum within six hours, suggesting an interaction between nanoparticle material and skin lipids. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. The simulation approach to lipid-protein interactions.

    Science.gov (United States)

    Paramo, Teresa; Garzón, Diana; Holdbrook, Daniel A; Khalid, Syma; Bond, Peter J

    2013-01-01

    The interactions between lipids and proteins are crucial for a range of biological processes, from the folding and stability of membrane proteins to signaling and metabolism facilitated by lipid-binding proteins. However, high-resolution structural details concerning functional lipid/protein interactions are scarce due to barriers in both experimental isolation of native lipid-bound complexes and subsequent biophysical characterization. The molecular dynamics (MD) simulation approach provides a means to complement available structural data, yielding dynamic, structural, and thermodynamic data for a protein embedded within a physiologically realistic, modelled lipid environment. In this chapter, we provide a guide to current methods for setting up and running simulations of membrane proteins and soluble, lipid-binding proteins, using standard atomistically detailed representations, as well as simplified, coarse-grained models. In addition, we outline recent studies that illustrate the power of the simulation approach in the context of biologically relevant lipid/protein interactions.

  18. Water distribution function across the curved lipid bilayer: SANS study

    International Nuclear Information System (INIS)

    Kiselev, M.A.; Zemlyanaya, E.V.; Ryabova, N.Y.; Hauss, T.; Dante, S.; Lombardo, D.

    2008-01-01

    The neutron scattering length density across the membrane is simulated on the basis of fluctuated model of lipid bilayer. The use of a separated form factors method has been applied for the identification of the structural features of the polydispersed unilamellar DMPC vesicle system. The hydration of vesicle is described by sigmoid distribution function of the water molecules. The application of the model to the obtained SANS spectra allow the determination of the main parameters of the system, such as the average vesicle radius (and its polydispersity), the membrane thickness, the thickness of hydrocarbon chain region, the number of water molecules located per lipid molecule, and the phospholipid surface area. Moreover the approach allow the calculation of some relevant parameters connected with the water distribution function across the bilayer system. The main features of the obtained results furnish an explanation of why lipid membrane is easily penetrated by the water molecules of the solution

  19. Discovery of Novel Lipid Profiles in PCOS: Do Insulin and Androgen Oppositely Regulate Bioactive Lipid Production?

    Science.gov (United States)

    Li, Shengxian; Chu, Qianqian; Ma, Jing; Sun, Yun; Tao, Tao; Huang, Rong; Liao, Yu; Yue, Jiang; Zheng, Jun; Wang, Lihua; Xue, Xinli; Zhu, Mingjiang; Kang, Xiaonan; Yin, Huiyong; Liu, Wei

    2017-03-01

    Polycystic ovary syndrome (PCOS) is a complex syndrome showing clinical features of an endocrine/metabolic disorder, including hyperinsulinemia and hyperandrogenism. Polyunsaturated fatty acids (PUFAs) and their derivatives, both tightly linked to PCOS and obesity, play important roles in inflammation and reproduction. This study aimed to investigate serum lipid profiles in newly diagnosed patients with PCOS using lipidomics and correlate these features with the hyperinsulinemia and hyperandrogenism associated with PCOS and obesity. Thirty-two newly diagnosed women with PCOS and 34 controls were divided into obese and lean subgroups. A PCOS rat model was used to validate results of the human studies. Serum lipid profiles, including phospholipids, free fatty acids (FFAs), and bioactive lipids, were analyzed using gas chromatography-mass spectrometry (MS) and liquid chromatography-MS. Elevation in phosphatidylcholine and a concomitant decrease in lysophospholipid were found in obese patients with PCOS vs lean controls. Obese patients with PCOS had decreased PUFA levels and increased levels of long-chain saturated fatty acids vs lean controls. Serum bioactive lipids downstream of arachidonic acid were increased in obese controls, but reduced in both obese and lean patients with PCOS vs their respective controls. Patients with PCOS showed abnormal levels of phosphatidylcholine, FFAs, and PUFA metabolites. Circulating insulin and androgens may have opposing effects on lipid profiles in patients with PCOS, particularly on the bioactive lipid metabolites derived from PUFAs. These clinical observations warrant further studies of the molecular mechanisms and clinical implications of PCOS and obesity. Copyright © 2017 by the Endocrine Society

  20. Sphingosine-1-Phosphate Lyase Deficient Cells as a Tool to Study Protein Lipid Interactions.

    Directory of Open Access Journals (Sweden)

    Mathias J Gerl

    Full Text Available Cell membranes contain hundreds to thousands of individual lipid species that are of structural importance but also specifically interact with proteins. Due to their highly controlled synthesis and role in signaling events sphingolipids are an intensely studied class of lipids. In order to investigate their metabolism and to study proteins interacting with sphingolipids, metabolic labeling based on photoactivatable sphingoid bases is the most straightforward approach. In order to monitor protein-lipid-crosslink products, sphingosine derivatives containing a reporter moiety, such as a radiolabel or a clickable group, are used. In normal cells, degradation of sphingoid bases via action of the checkpoint enzyme sphingosine-1-phosphate lyase occurs at position C2-C3 of the sphingoid base and channels the resulting hexadecenal into the glycerolipid biosynthesis pathway. In case the functionalized sphingosine looses the reporter moiety during its degradation, specificity towards sphingolipid labeling is maintained. In case degradation of a sphingosine derivative does not remove either the photoactivatable or reporter group from the resulting hexadecenal, specificity towards sphingolipid labeling can be achieved by blocking sphingosine-1-phosphate lyase activity and thus preventing sphingosine derivatives to be channeled into the sphingolipid-to-glycerolipid metabolic pathway. Here we report an approach using clustered, regularly interspaced, short palindromic repeats (CRISPR-associated nuclease Cas9 to create a sphingosine-1-phosphate lyase (SGPL1 HeLa knockout cell line to disrupt the sphingolipid-to-glycerolipid metabolic pathway. We found that the lipid and protein compositions as well as sphingolipid metabolism of SGPL1 knock-out HeLa cells only show little adaptations, which validates these cells as model systems to study transient protein-sphingolipid interactions.

  1. Imaging of blood plasma coagulation at supported lipid membranes.

    Science.gov (United States)

    Faxälv, Lars; Hume, Jasmin; Kasemo, Bengt; Svedhem, Sofia

    2011-12-15

    The blood coagulation system relies on lipid membrane constituents to act as regulators of the coagulation process upon vascular trauma, and in particular the 2D configuration of the lipid membranes is known to efficiently catalyze enzymatic activity of blood coagulation factors. This work demonstrates a new application of a recently developed methodology to study blood coagulation at lipid membrane interfaces with the use of imaging technology. Lipid membranes with varied net charges were formed on silica supports by systematically using different combinations of lipids where neutral phosphocholine (PC) lipids were mixed with phospholipids having either positively charged ethylphosphocholine (EPC), or negatively charged phosphatidylserine (PS) headgroups. Coagulation imaging demonstrated that negatively charged SiO(2) and membrane surfaces exposing PS (obtained from liposomes containing 30% of PS) had coagulation times which were significantly shorter than those for plain PC membranes and EPC exposing membrane surfaces (obtained from liposomes containing 30% of EPC). Coagulation times decreased non-linearly with increasing negative surface charge for lipid membranes. A threshold value for shorter coagulation times was observed below a PS content of ∼6%. We conclude that the lipid membranes on solid support studied with the imaging setup as presented in this study offers a flexible and non-expensive solution for coagulation studies at biological membranes. It will be interesting to extend the present study towards examining coagulation on more complex lipid-based model systems. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Thyroid hormones and lipid phosphorus in mice

    Energy Technology Data Exchange (ETDEWEB)

    Thakare, U R; Ganatra, R D; Shah, D H [Bhabha Atomic Research Centre, Bombay (India). Radiation Medicine Centre

    1978-04-01

    In vivo studies in mice injected intravenously with /sup 125/I-triiodothyronine (T-3) showed a linear relationship between the uptake of the labelled hormone by the tissue and the lipid phosphorous content of the same tissue. However, studies with /sup 125/I-thyroxine failed to show a similar relationship between the lipid phosphorous content of the organ and the uptake of radioactive hormone by the same organ. In vitro studies using equilibrium dialysis technique with isolated lipid extracts of various organs and radioactive thyroid hormones (T-3 and T-4) did not show any relation between the lipid P and the uptake of labelled hormone. On the basis of the observed discrepancy between in vivo and in vitro studies, it is postulated that an organized lipoprotein structure at the cell membrane may be responsible for the entry of the thyroid hormones.

  3. Open Field Study of Some Zea mays Hybrids, Lipid Compounds and Fumonisins Accumulation

    Science.gov (United States)

    Giorni, Paola; Dall’Asta, Chiara; Reverberi, Massimo; Scala, Valeria; Ludovici, Matteo; Cirlini, Martina; Galaverna, Gianni; Fanelli, Corrado; Battilani, Paola

    2015-01-01

    Lipid molecules are increasingly recognized as signals exchanged by organisms interacting in pathogenic and/or symbiotic ways. Some classes of lipids actively determine the fate of the interactions. Host cuticle/cell wall/membrane components such as sphingolipids and oxylipins may contribute to determining the fate of host–pathogen interactions. In the present field study, we considered the relationship between specific sphingolipids and oxylipins of different hybrids of Zea mays and fumonisin by F. verticillioides, sampling ears at different growth stages from early dough to fully ripe. The amount of total and free fumonisin differed significantly between hybrids and increased significantly with maize ripening. Oxylipins and phytoceramides changed significantly within the hybrids and decreased with kernel maturation, starting from physiological maturity. Although the correlation between fumonisin accumulation and plant lipid profile is certain, the data collected so far cannot define a cause-effect relationship but open up new perspectives. Therefore, the question—“Does fumonisin alter plant lipidome or does plant lipidome modulate fumonisin accumulation?”—is still open. PMID:26378580

  4. Open Field Study of Some Zea mays Hybrids, Lipid Compounds and Fumonisins Accumulation

    Directory of Open Access Journals (Sweden)

    Paola Giorni

    2015-09-01

    Full Text Available Lipid molecules are increasingly recognized as signals exchanged by organisms interacting in pathogenic and/or symbiotic ways. Some classes of lipids actively determine the fate of the interactions. Host cuticle/cell wall/membrane components such as sphingolipids and oxylipins may contribute to determining the fate of host–pathogen interactions. In the present field study, we considered the relationship between specific sphingolipids and oxylipins of different hybrids of Zea mays and fumonisin by F. verticillioides, sampling ears at different growth stages from early dough to fully ripe. The amount of total and free fumonisin differed significantly between hybrids and increased significantly with maize ripening. Oxylipins and phytoceramides changed significantly within the hybrids and decreased with kernel maturation, starting from physiological maturity. Although the correlation between fumonisin accumulation and plant lipid profile is certain, the data collected so far cannot define a cause-effect relationship but open up new perspectives. Therefore, the question—“Does fumonisin alter plant lipidome or does plant lipidome modulate fumonisin accumulation?”—is still open.

  5. Modeling growth, lipid accumulation and lipid turnover in submerged batch cultures of Umbelopsis isabellina

    NARCIS (Netherlands)

    Meeuwse, P.; Akbari, P.; Tramper, J.; Rinzema, A.

    2012-01-01

    The production of lipids by oleaginous yeast and fungi becomes more important because these lipids can be used for biodiesel production. To understand the process of lipid production better, we developed a model for growth, lipid production and lipid turnover in submerged batch fermentation. This

  6. The impact of resveratrol in lipid bilayers

    DEFF Research Database (Denmark)

    Shen, Chen; Ghellinck, Alexis de; Fragneto, Giovanna

    The natural antioxidant resveratrol, contained in the skin of grape and accordingly in red wine, has significant health effects such as cardiovascular protection and anti-oxidation. Clinical trials of resveratrol as prophylactic or even therapeutic drug are ongoing. Most probably, the working...... mechanism is unspecific. However, there are only few biophysical studies regarding the impact of resveratrol on lipid membranes. Here, results from a neutron reflectometry investigation on solid supported di-palmitoyl-phosphatidyl-choline (DPPC) bilayers with incorporated resveratrol are presented. The data...... show an accumulation of resveratrol in between the headgroups and evidence its absence in the hydrophobic core. Without a removal mechanism, the headgroup region hosts up to ~25 mol% of resveratrol. The presence of resveratrol induces a change of the tilt angle of the PC headgroups to a more upright...

  7. The impact of resveratrol in lipid bilayers

    DEFF Research Database (Denmark)

    Shen, Chen; de Ghellinck, Alexis; Fragneto, Giovanna

    The natural antioxidant resveratrol, contained in the skin of red grape and accordingly in their wines, is hold liable for health impacts such as cardiovascular protection and anti-oxidative effect. Clinical trials of resveratrol as prophylactic or even therapeutic drug are ongoing. However, basic...... knowledge on its probable working mechanism is rare. In this biophysical study, neutron reflectometry was used to investigate the direct impact of resveratrol on lipid membranes with solid supported bilayers. When interacting with di- palmitoyl-phosphatidyl-choline (DPPC) bilayers, resveratrol accumulates...... in between the headgroups but is absent in the hydrophobic core. Without a biogenic removal mechanism, the headgroup region may host up to ~25 mol% of resveratrol. The average thickness and the interfacial roughness of the headgroup layer are increased. From the structural results, the average tilting...

  8. Unraveling lipid metabolism in lipid-dependent pathogenic Malassezia yeasts

    OpenAIRE

    Celis Ramirez, A.M.

    2017-01-01

    Malassezia yeasts are lipid-dependent fungal species that are common members of the human and animal skin microbiota. The lipid-dependency is a crucial trait in the adaptation process to grow on the skin but also plays a role in their pathogenic life style. Malassezia species can cause several skin infections like dandruff or seborrheic dermatitis but also bloodstream infections. Understanding the lipid metabolism in Malassezia is essential to understand its life style as skin commensal and p...

  9. Study of the ion-channel behavior on glassy carbon electrode supported bilayer lipid membranes stimulated by perchlorate anion

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhiquan; Shi, Jun; Huang, Weimin, E-mail: huangwm@jlu.edu.cn

    2015-10-01

    In this paper, a kind of didodecyldimethylammonium bromide (DDAB) layer membranes was supported on a glassy carbon electrode (GCE). We studied the ion channel behavior of the supported bilayer lipid membrane by scanning electrochemical microscopy (SCEM) in tris(2,2′-bipyridine) ruthenium(II) solution. Perchlorate anion was used as a presence of stimulus and ruthenium(II) complex cations as the probing ions for the measurement of SECM, the lipid membrane channel was opened and exhibited the behavior of distinct SECM positive feedback curve. The channel was in a closed state in the absence of perchlorate anions while reflected the behavior of SECM negative feedback curve. The rates of electron transfer reaction in the lipid membranes surface were detected and it was dependant on the potential of SECM. - Highlights: • The rates of electron transfer reaction in the lipid membranes surface were detected. • Dynamic investigations of ion-channel behavior of supported bilayer lipid membranes by scanning electrochemical microscopy • A novel way to explore the interaction between molecules and supported bilayer lipid membranes.

  10. Lipid storage myopathies.

    Science.gov (United States)

    Bruno, Claudio; Dimauro, Salvatore

    2008-10-01

    The aim of this review is to provide an update on disorders of lipid metabolism affecting skeletal muscle exclusively or predominantly and to summarize recent clinical, genetic, and therapeutic studies in this field. Over the past 5 years, new clinical phenotypes and genetic loci have been described, unusual pathogenic mechanisms have been elucidated, and novel pharmacological approaches have been developed. At least one genetic defect responsible for the myopathic form of CoQ10 deficiency has been identified, causing a disorder that is allelic with the late-onset riboflavine-responsive form of multiple acyl-coenzyme A dehydrogenation deficiency. Novel mechanisms involved in the lipolytic breakdown of cellular lipid depots have been described and have led to the identification of genes and mutations responsible for multisystemic neutral lipid storage disorders, characterized by accumulation of triglyceride in multiple tissues, including muscle. Defects in lipid metabolism can affect either the mitochondrial transport and oxidation of exogenous fatty acid or the catabolism of endogenous triglycerides. These disorders impair energy production and almost invariably involve skeletal muscle, causing progressive myopathy with muscle weakness, or recurrent acute episodes of rhabdomyolysis triggered by exercise, fasting, or infections. Clinical and genetic characterization of these disorders has important implications both for accurate diagnostic approach and for development of therapeutic strategies.

  11. Lipid polymorphism and the functional roles of lipids in biological membranes

    NARCIS (Netherlands)

    Cullis, P.R.; Kruijff, B. de

    1979-01-01

    The reasons for the great variety of lipids found in biological membranes, and the relations between lipid composition and membrane function pose major unsolved problems in membrane biology. Perhaps the only major functional role of lipids which may be regarded as firmly established involves the

  12. A Role of Lipid Metabolism during Cumulus-Oocyte Complex Maturation: Impact of Lipid Modulators to Improve Embryo Production

    Directory of Open Access Journals (Sweden)

    E. G. Prates

    2014-01-01

    Full Text Available Oocyte intracellular lipids are mainly stored in lipid droplets (LD providing energy for proper growth and development. Lipids are also important signalling molecules involved in the regulatory mechanisms of maturation and hence in oocyte competence acquisition. Recent studies show that LD are highly dynamic organelles. They change their shape, volume, and location within the ooplasm as well as their interaction with other organelles during the maturation process. The droplets high lipid content has been correlated with impaired oocyte developmental competence and low cryosurvival. Yet the underlying mechanisms are not fully understood. In particular, the lipid-rich pig oocyte might be an excellent model to understand the role of lipids and fatty acid metabolism during the mammalian oocyte maturation and their implications on subsequent monospermic fertilization and preimplantation embryo development. The possibility of using chemical molecules to modulate the lipid content of oocytes and embryos to improve cryopreservation as well as its biological effects during development is here described. Furthermore, these principles of lipid content modulation may be applied not only to germ cells and embryo cryopreservation in livestock production but also to biomedical fundamental research.

  13. Ultrastructural study on dynamics of lipid bodies and plastids during ripening of chili pepper fruits.

    Science.gov (United States)

    Liu, Lin

    2013-03-01

    Dynamics of lipid bodies and plastids in chili pepper fruits during ripening were investigated by means of transmission electron microscopy. Mesocarp of chili pepper fruits consists of collenchyma, normal parenchyma, and huge celled parenchyma. In mature green fruits, plastids contain numerous thylakoids that are well organized into grana in collenchyma, a strikingly huge amount of starch and irregularly organized thylakoids in normal parenchyma, and simple tubes rather than thylakoids in huge celled parenchyma. These morphological features suggest that plastids are chloroplasts in collenchyma, chloroamyloplasts in normal parenchyma, proplastids in huge celled parenchyma. As fruits ripen to red, plastids in all cell types convert to chromoplasts and, concomitantly, lipid bodies accumulate in both cytoplasm and chromoplasts. Cytosolic lipid bodies are lined up in a regular layer adjacent to plasma membrane. The cytosolic lipid body consists of a core surrounded by a membrane. The core is comprised of a more electron-dense central part enclosed by a slightly less electron-dense peripheral layer. Plastidial lipid bodies in collenchyma, normal parenchyma, and endodermis initiate as plastoglobuli, which in turn convert to rod-like structures. Therefore, plastidial lipid bodies are more dynamic than cytosolic lipid bodies. Both cytosolic and plastidial lipid bodies contain rich unsaturated lipids. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Lysosomal lipid storage diseases.

    Science.gov (United States)

    Schulze, Heike; Sandhoff, Konrad

    2011-06-01

    Lysosomal lipid storage diseases, or lipidoses, are inherited metabolic disorders in which typically lipids accumulate in cells and tissues. Complex lipids, such as glycosphingolipids, are constitutively degraded within the endolysosomal system by soluble hydrolytic enzymes with the help of lipid binding proteins in a sequential manner. Because of a functionally impaired hydrolase or auxiliary protein, their lipid substrates cannot be degraded, accumulate in the lysosome, and slowly spread to other intracellular membranes. In Niemann-Pick type C disease, cholesterol transport is impaired and unesterified cholesterol accumulates in the late endosome. In most lysosomal lipid storage diseases, the accumulation of one or few lipids leads to the coprecipitation of other hydrophobic substances in the endolysosomal system, such as lipids and proteins, causing a "traffic jam." This can impair lysosomal function, such as delivery of nutrients through the endolysosomal system, leading to a state of cellular starvation. Therapeutic approaches are currently restricted to mild forms of diseases with significant residual catabolic activities and without brain involvement.

  15. Perspectives on marine zooplankton lipids

    DEFF Research Database (Denmark)

    Kattner, G.; Hagen, W.; Lee, R.F.

    2007-01-01

    We developed new perspectives to identify important questions and to propose approaches for future research on marine food web lipids. They were related to (i) structure and function of lipids, (ii) lipid changes during critical life phases, (iii) trophic marker lipids, and (iv) potential impact...... of climate change. The first addresses the role of lipids in membranes, storage lipids, and buoyancy with the following key question: How are the properties of membranes and deposits affected by the various types of lipids? The second deals with the importance of various types of lipids during reproduction......, development, and resting phases and addresses the role of the different storage lipids during growth and dormancy. The third relates to trophic marker lipids, which are an important tool to follow lipid and energy transfer through the food web. The central question is how can fatty acids be used to identify...

  16. In vitro study of interaction of synaptic vesicles with lipid membranes

    International Nuclear Information System (INIS)

    Ghosh, S K; Castorph, S; Salditt, T; Konovalov, O; Jahn, R; Holt, M

    2010-01-01

    The fusion of synaptic vesicles (SVs) with the plasma membrane in neurons is a crucial step in the release of neurotransmitters, which are responsible for carrying signals between nerve cells. While many of the molecular players involved in this fusion process have been identified, a precise molecular description of their roles in the process is still lacking. A case in point is the plasma membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP 2 ). Although PIP 2 is known to be essential for vesicle fusion, its precise role in the process remains unclear. We have re-investigated the role of this lipid in membrane structure and function using the complementary experimental techniques of x-ray reflectivity, both on lipid monolayers at an air-water interface and bilayers on a solid support, and grazing incidence x-ray diffraction on lipid monolayers. These techniques provide unprecedented access to structural information at the molecular level, and detail the profound structural changes that occur in a membrane following PIP 2 incorporation. Further, we also confirm and extend previous findings that the association of SVs with membranes is enhanced by PIP 2 incorporation, and reveal the structural changes that underpin this phenomenon. Further, the association is further intensified by a physiologically relevant amount of Ca 2+ ions in the subphase of the monolayer, as revealed by the increase in interfacial pressure seen with the lipid monolayer system. Finally, a theoretical calculation concerning the products arising from the fusion of these SVs with proteoliposomes is presented, with which we aim to illustrate the potential future uses of this system.

  17. Raman probing of lipids, proteins, and mitochondria in skeletal myocytes: a case study on obesity

    DEFF Research Database (Denmark)

    Brazhe, Nadezda A.; Nikelshparg, Evelina I.; Prats, Clara

    2017-01-01

    We propose a novel approach to assess simultaneously lipid composition in lipid droplets, the redox state of cytochromes, and the relative amount of [Fe–S] clusters in the electron transport chain in the mitochondria of skeletal myocytes by means of near-infrared Raman spectroscopy. Mitochondria...... technique allows to estimate qualitatively the relative amount of cholesterol and unsaturated lipids, ordering of lipid phase in lipid droplets, changes in the redox state of c-type and b-type cytochromes, and the relative amount of [Fe–S] clusters in the mitochondria of intact myocytes. The proposed...

  18. Association between spicy food consumption and lipid profiles in adults: a nationwide population-based study.

    Science.gov (United States)

    Xue, Yong; He, Tingchao; Yu, Kai; Zhao, Ai; Zheng, Wei; Zhang, Yumei; Zhu, Baoli

    2017-07-01

    CVD remains the leading cause of mortality worldwide, with abnormal lipid metabolism as a major risk factor. The aim of this study was to investigate associations between spicy food consumption and serum lipids in Chinese adults. Data were extracted from the 2009 phase of the China Health and Nutrition Survey, consisting of 6774 apparently healthy Chinese adults aged 18-65 years. The frequency of consumption and degree of pungency of spicy food were self-reported, and regular spicy food consumption was assessed using three consecutive 24-h recalls. Total cholesterol, TAG, LDL-cholesterol and HDL-cholesterol in fasting serum were measured. Multilevel mixed-effects models were constructed to estimate associations between spicy food consumption and serum lipid profiles. The results showed that the frequency and the average amount of spicy food intake were both inversely associated with LDL-cholesterol and LDL-cholesterol:HDL-cholesterol ratio (all P for trendfood (≥5 times/week) and who consumed spicy food perceived as moderate in pungency were significantly higher than those who did not (both Pfood intake and the degree of pungency in spicy food were positively associated with TAG (all P for trendfood consumption was inversely associated with serum cholesterol and positively associated with serum TAG, and additional studies are needed to confirm the findings as well as to elucidate the potential roles of spicy food consumption in lipid metabolism.

  19. STUDY OF THE CHANGES IN SERUM LIPIDS FOLLOWING MERCURY INTOXIFICATION

    Directory of Open Access Journals (Sweden)

    M TAHER

    2000-12-01

    Full Text Available Background. The toxicity of mercury which is used as mercury chloride in different parts of living world has been reported in literature. In our knowledge, however, these reports are on the effects of mercury on serum blood parameters. As lipids have important role in cell metabolism, we decided to study the effects of mercury on blood parameters which are related to lipid metabolism as well as its effect on hepatocyte triglycerides. Methods. Each group of 5 rats were treated with daily IP injections of either 10 mg/kg (Body Weight for 5 and 10 days or 5 mg/kg B.W. for 30 and 60 days, before determination of serum levels of triglycerides, cholesterol and lipoprotein fractions. Results. The results obtained are as follows. Daily intraperitoneal injection of 10 mg/kg B.W of mercury for 5 and 10 days elevated serum triglycerides by (10.9, 19.3 LDLc (16.5, 22.5 VLDLc (10.9, ,19.3 and hepatocytes containing triglycerides (105.1, 136.3 percent respectively. HDLc was decreased by (13.4, 17.3 percent. Daily intraperitoneal injection of 5 mg/kg body weight of mercury for 30 and 60 days elevated serum triglycerides by (34.7, 47.4. LDLc (28.9, 33.3, VLDLc (34.7, 47.4 and hepatocytes containing triglycerides (177.3, 213.4 percent respectively. HDLc was lowered by (22.9, 27.7 percent. Discussion. The results showed that mercury could affect lipid metabloism in a dose and time dependent manner. This effect might be considered as a possilbe cause of hyperlipidemia in those who are intoxified with this element.

  20. [Lipid and metabolic profiles in adolescents are affected more by physical fitness than physical activity (AVENA study)].

    Science.gov (United States)

    García-Artero, Enrique; Ortega, Francisco B; Ruiz, Jonatan R; Mesa, José L; Delgado, Manuel; González-Gross, Marcela; García-Fuentes, Miguel; Vicente-Rodríguez, Germán; Gutiérrez, Angel; Castillo, Manuel J

    2007-06-01

    To determine whether the level of physical activity or physical fitness (i.e., aerobic capacity and muscle strength) in Spanish adolescents influences lipid and metabolic profiles. From a total of 2859 Spanish adolescents (age 13.0-18.5 years) taking part in the AVENA (Alimentación y Valoración del Estado Nutricional en Adolescentes) study, 460 (248 male, 212 female) were randomly selected for blood analysis. Their level of physical activity was determined by questionnaire. Aerobic capacity was assessed using the Course-Navette test. Muscle strength was evaluated using manual dynamometry, the long jump test, and the flexed arm hang test. A lipid-metabolic cardiovascular risk index was derived from the levels of triglycerides, low-density lipoprotein cholesterol (LDLC), high-density lipoprotein cholesterol (HDLC), and glucose. No relationship was found between the level of physical activity and lipid-metabolic index in either sex. In contrast, there was an inverse relationship between the lipid-metabolic index and aerobic capacity in males (P=.003) after adjustment for physical activity level and muscle strength. In females, a favorable lipid-metabolic index was associated with greater muscle strength (P=.048) after adjustment for aerobic capacity. These results indicate that, in adolescents, physical fitness, and not physical activity, is related to lipid and metabolic cardiovascular risk. Higher aerobic capacity in males and greater muscle strength in females were associated with lower lipid and metabolic risk factors for cardiovascular disease.

  1. Lipid Lowering Effect of Punica granatum L. Peel in High Lipid Diet Fed Male Rats

    Directory of Open Access Journals (Sweden)

    Alireza Sadeghipour

    2014-01-01

    Full Text Available Many herbal medicines have been recommended for the treatment of dyslipidemia. The antilipidemic effect of hydroethanolic extract of pomegranate peel (Punica granatum L. was investigated in high lipid diet fed male rats. Intraperitoneally administration of pomegranate peel extract (50, 100, 200, and 300 mg/kg body weight for 23 days on the levels of serum cholesterol, triglycerides, LDL, HDL, alkaline phosphatase (AP, aspartate aminotransferase (AST, and alanine aminotransferase (ALT in high lipid diet fed male rats was evaluated. Treatment of pomegranate extract decreased body weight in treated rats, significantly. Administration of the plant extract significantly decreased serum total cholesterol, triglycerides, LDL-C, alkaline phosphatise, AST, and ALT levels, whereas it increased serum HDL-C in high lipid diet fed rats in comparison to saline control group. Also, histopathological study showed that treatment of pomegranate peel extract attenuates liver damage in high lipid diet fed rats in comparison to saline group. It is concluded that the plant should be considered as an excellent candidate for future studies on dyslipidemia.

  2. Lipid Lowering Effect of Punica granatum L. Peel in High Lipid Diet Fed Male Rats

    Science.gov (United States)

    Sadeghipour, Alireza; Ilchizadeh Kavgani, Ali; Ghahramani, Reza; Shahabzadeh, Saleh; Anissian, Ali

    2014-01-01

    Many herbal medicines have been recommended for the treatment of dyslipidemia. The antilipidemic effect of hydroethanolic extract of pomegranate peel (Punica granatum L.) was investigated in high lipid diet fed male rats. Intraperitoneally administration of pomegranate peel extract (50, 100, 200, and 300 mg/kg body weight) for 23 days on the levels of serum cholesterol, triglycerides, LDL, HDL, alkaline phosphatase (AP), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) in high lipid diet fed male rats was evaluated. Treatment of pomegranate extract decreased body weight in treated rats, significantly. Administration of the plant extract significantly decreased serum total cholesterol, triglycerides, LDL-C, alkaline phosphatise, AST, and ALT levels, whereas it increased serum HDL-C in high lipid diet fed rats in comparison to saline control group. Also, histopathological study showed that treatment of pomegranate peel extract attenuates liver damage in high lipid diet fed rats in comparison to saline group. It is concluded that the plant should be considered as an excellent candidate for future studies on dyslipidemia. PMID:25295067

  3. Phospatidylserine or ganglioside--which of anionic lipids determines the effect of cationic dextran on lipid membrane?

    Science.gov (United States)

    Hąc-Wydro, Katarzyna; Wydro, Paweł; Cetnar, Andrzej; Włodarczyk, Grzegorz

    2015-02-01

    In this work the influence of cationic polymer, namely diethylaminoethyl DEAE-dextran on model lipid membranes was investigated. This polymer is of a wide application as a biomaterial and a drug carrier and its cytotoxicity toward various cancer cells was also confirmed. It was suggested that anticancer effect of cationic dextran is connected with the binding of the polymer to the negatively charged sialic acid residues overexpressed in cancer membrane. This fact encouraged us to perform the studies aimed at verifying whether the effect of cationic DEAE-dextran on membrane is determined only by the presence of the negatively charged lipid in the system or the kind of anionic lipid is also important. To reach this goal systematic investigations on the effect of dextran on various one-component lipid monolayers and multicomponent hepatoma cell model membranes differing in the level and the kind of anionic lipids (phosphatidylserine, sialic acid-containing ganglioside GM3 or their mixture) were done. As evidenced the results the effect of DEAE-dextran on the model system is determined by anionic lipid-polymer electrostatic interactions. However, the magnitude of the effect of cationic polymer is strongly dependent on the kind of anionic lipid in the model system. Namely, the packing and ordering of the mixtures containing ganglioside GM3 were more affected by DEAE-dextran than phosphatidylserine-containing monolayers. Although the experiments were done on model systems and therefore further studies are highly needed, the collected data may indicate that ganglioside may be important in the differentiation of the effect of cationic dextran on membranes. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Preservation of Microbial Lipids in Geothermal Sinters

    NARCIS (Netherlands)

    Kaur, G.; Mountain, B.W.; Hopmans, E.C.; Pancost, R.D.

    2011-01-01

    Lipid biomarkers are widely used to study the earliest life on Earth and have been invoked as potential astrobiological markers, but few studies have assessed their survival and persistence in geothermal settings. Here, we investigate lipid preservation in active and inactive geothermal silica

  5. Effects of acute exercise on lipid content and dietary lipid uptake in liver and skeletal muscle of lean and diabetic rats

    NARCIS (Netherlands)

    Janssens, Sharon; Jonkers, Richard A. M.; Groen, Albert K.; Nicolay, Klaas; van Loon, Luc J. C.; Prompers, Jeanine J.

    2015-01-01

    Insulin resistance is associated with ectopic lipid accumulation. Physical activity improves insulin sensitivity, but the impact of exercise on lipid handling in insulin-resistant tissues remains to be elucidated. The present study characterizes the effects of acute exercise on lipid content and

  6. Altered Clock and Lipid Metabolism-Related Genes in Atherosclerotic Mice Kept with Abnormal Lighting Condition

    Directory of Open Access Journals (Sweden)

    Zhu Zhu

    2016-01-01

    Full Text Available Background. The risk of atherosclerosis is elevated in abnormal lipid metabolism and circadian rhythm disorder. We investigated whether abnormal lighting condition would have influenced the circadian expression of clock genes and clock-controlled lipid metabolism-related genes in ApoE-KO mice. Methods. A mouse model of atherosclerosis with circadian clock genes expression disorder was established using ApoE-KO mice (ApoE-KO LD/DL mice by altering exposure to light. C57 BL/6J mice (C57 mice and ApoE-KO mice (ApoE-KO mice exposed to normal day and night and normal diet served as control mice. According to zeitgeber time samples were acquired, to test atheromatous plaque formation, serum lipids levels and rhythmicity, clock genes, and lipid metabolism-related genes along with Sirtuin 1 (Sirt1 levels and rhythmicity. Results. Atherosclerosis plaques were formed in the aortic arch of ApoE-KO LD/DL mice. The serum lipids levels and oscillations in ApoE-KO LD/DL mice were altered, along with the levels and diurnal oscillations of circadian genes, lipid metabolism-associated genes, and Sirt1 compared with the control mice. Conclusions. Abnormal exposure to light aggravated plaque formation and exacerbated disorders of serum lipids and clock genes, lipid metabolism genes and Sirt1 levels, and circadian oscillation.

  7. COMPARATIVE STUDY TO EVALUATE LIPID-LOWERING EFFECT OF

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    Niteesh Shanbag

    2017-03-01

    Full Text Available BACKGROUND Dyslipidaemia is a widely established risk factor for coronary artery disease. As Asians differ in pattern of various lipid abnormalities than non-Asians, this study was undertaken to compare efficacy of commonly administrated drugs, atorvastatin and fenofibrate. MATERIALS AND METHODS The present study was carried out in 100 diagnosed cases of hypertriglyceridaemia divided into two groups, A and B. The mean, standard deviation, standard error of mean and t value were calculated following 12 weeks of therapy of atorvastatin 10 mg in group A and micronized fenofibrate in group B. RESULTS Our study showed that fenofibrate is more efficacious in reducing the levels of triglycerides and rising level of HDL cholesterol, while atorvastatin is more efficacious in reducing LDL cholesterol. CONCLUSION Micronized fenofibrate has more efficiency in reducing triglycerides and raising HDL. Atorvastatin is more efficacious in reducing LDL levels.

  8. Dissolved lipid production in the Northern Adriatic (Mediterranean) in response to sea surface warmin

    Science.gov (United States)

    Gasparovic, Blazenka; Novak, Tihana; Godrijan, Jelena; Mlakar, Marina; MAric, Daniela; Djakovac, Tamara

    2017-04-01

    Marine dissolved organic matter (OM) represents one of the largest active pools of organic carbon in the global carbon cycle. Oceans and seas are responsible for half of global primary production. Ocean warming caused by climate change is already starting to impact the marine life that necessary will have impact on ocean productivity. The partition of OM production by phytoplankton (major OM producer in seas and ocens) in the conditions of rising temperatures may considerably change. This has implications for the export of organic matter from the photic zone. In this study, we set out to see how annual temperature changes between 10 and 30 C in the Northern Adriatic (Mediterranean) affect production of DOM and particularly dissolved lipids and lipid classes. We have sampled at two stations being oligotrophic and mesotrophic where we expected different system reaction to temperature changes. In addition, we performed microcosm incubations covering temperature range of the NA with nutrient amendments to test whether changes in the available nutrients would reflect those of dissolved OM in the NA. We have selected to work with extracellular OM produced during growth of diatom Chaetoceros curvisetus cultures according to the criteria that genera Chaetoceros are important component of the phytoplankton in the NA and are often among bloom-forming taxa. Details on the dissolved lipid and lipid classes production as plankton responce to rising temperature will be discussed.

  9. How can lipid nanocarriers improve transdermal delivery of olanzapine?

    Science.gov (United States)

    Iqbal, Nimra; Vitorino, Carla; Taylor, Kevin M G

    2017-06-01

    The development of a transdermal nanocarrier drug delivery system with potential for the treatment of psychiatric disorders, such as schizophrenia and bipolar disorder, is described. Lipid nanocarriers (LN), encompassing various solid:liquid lipid compositions were formulated and assessed as potential nanosystems for transdermal delivery of olanzapine. A previously optimized method of hot high pressure homogenization (HPH) was adopted for the production of the LN, which comprised solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC) and nanoemulsions (NE). Precirol  ® was selected as the solid lipid for progression of studies. SLN exhibited the best performance for transdermal delivery of olanzapine, based on in vitro release and permeation studies, coupled with results from physicochemical characterization of several solid:liquid lipid formulations. Stability tests, performed to give an indication of long-term storage behavior of the formulations, were in good agreement with previous studies for the best choice of solid:liquid lipid ratio. Overall, these findings highlight the SLN-based formulation as promising for the further inclusion in and production of transdermal patches, representing an innovative therapeutic approach.

  10. PENGEMBANGAN SISTEM NANOSTRUCTURED LIPID CARRIERS (NLC MELOXICAM DENGAN LIPID MONOSTEARIN DAN MIGLYOL 808 MENGGUNAKAN METODE EMULSIFIKASI

    Directory of Open Access Journals (Sweden)

    Rahmi Annisa

    2016-06-01

    Full Text Available The aim this study was to determine the effect of Monostearin and Miglyol 808 lipid ratio in NLC system formulation resulting in physicochemical characteristics, release rate, and penetration rate. The NLC making was done by using emulsification method. In the formulation of NLC meloxicam, 3 different lipid ratios were used, including ratios of 6:4, 7:3, 8:2.  Meloxicam served as active ingredient, monostearin served as solid lipid, miglyol 808 served as a liquid lipid, and tween 80 was surfactant. NLC meloxicam physicochemical characteristics include tests of organoleptic, pH, viscosity, particle size, particle morphology and entrapment efficiency. NLC meloxicam belongs to semisolid preparations with pH value range of 5,72-5,87. Increasing viscosity of NLC system are cause by increase of solid lipid. The measurement results of particle size of three different lipid formulas indicated that the lipid particle size was 80%. The determination of release rate (flux and penetration rate (flux was conducted by using Franz diffusion cells with a cellophane membrane for the release and Wistar rat’s skin membrane for the penetration. The release rate values of three NLC meloxicam formulas showed p value (sig 0,005, while the penetration rate obtained p value (sig 0,091. Keywords: NLC, meloxicam, physicochemical characterization, release rate and penetration rate

  11. SERUM LIPID PROFILE AS AN ETIOLOGY OF VERTIGO : A STUDY

    OpenAIRE

    Sami; Satveer Singh

    2015-01-01

    A prospective study of lipid profile was done in 60 patients of vertigo at E.L.M.C. Lucknow from 2011 to 2014. All components of serum cholesterol were analyzed. Serum cholesterol and hyperlipidemia as an etiology of the atherosclerosis of all blood vessel s also have a role in vestibulo - cochlear vessels. It was found that there were 34 females and 26 males and maximum number of patients (63.33%) in the age group of 31 - 50y...

  12. Incorporation of liquid lipid in lipid nanoparticles for ocular drug delivery enhancement

    International Nuclear Information System (INIS)

    Shen Jie; Sun Minjie; Ping Qineng; Ying Zhi; Liu Wen

    2010-01-01

    The present work investigates the effect of liquid lipid incorporation on the physicochemical properties and ocular drug delivery enhancement of nanostructured lipid carriers (NLCs) and attempts to elucidate in vitro and in vivo the potential of NLCs for ocular drug delivery. The CyA-loaded or fluorescein-marked nanocarriers composed of Precifac ATO 5 and Miglyol 840 (as liquid lipid) were prepared by melting-emulsion technology, and the physicochemical properties of nanocarriers were determined. The uptake of nanocarriers by human corneal epithelia cell lines (SDHCEC) and rabbit cornea was examined. Ex vivo fluorescence imaging was used to investigate the ocular distribution of nanocarriers. The in vitro cytotoxicity and in vivo acute tolerance were evaluated. The higher drug loading capacity and improved in vitro sustained drug release behavior of lipid nanoparticles was found with the incorporation of liquid lipid in lipid nanoparticles. The uptake of nanocarriers by the SDHCEC was increased with the increase in liquid lipid loading. The ex vivo fluorescence imaging of the ocular tissues indicated that the liquid lipid incorporation could improve the ocular retention and penetration of ocular therapeutics. No alternation was macroscopically observed in vivo after ocular surface exposure to nanocarriers. These results indicated that NLC was a biocompatible and potential nanocarrier for ocular drug delivery enhancement.

  13. Incorporation of liquid lipid in lipid nanoparticles for ocular drug delivery enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Shen Jie; Sun Minjie; Ping Qineng; Ying Zhi; Liu Wen, E-mail: Pingqn2004@yahoo.com.cn [School of Pharmacy, China Pharmaceutical University, 24 Tongjia Xiang, Nanjing (China)

    2010-01-15

    The present work investigates the effect of liquid lipid incorporation on the physicochemical properties and ocular drug delivery enhancement of nanostructured lipid carriers (NLCs) and attempts to elucidate in vitro and in vivo the potential of NLCs for ocular drug delivery. The CyA-loaded or fluorescein-marked nanocarriers composed of Precifac ATO 5 and Miglyol 840 (as liquid lipid) were prepared by melting-emulsion technology, and the physicochemical properties of nanocarriers were determined. The uptake of nanocarriers by human corneal epithelia cell lines (SDHCEC) and rabbit cornea was examined. Ex vivo fluorescence imaging was used to investigate the ocular distribution of nanocarriers. The in vitro cytotoxicity and in vivo acute tolerance were evaluated. The higher drug loading capacity and improved in vitro sustained drug release behavior of lipid nanoparticles was found with the incorporation of liquid lipid in lipid nanoparticles. The uptake of nanocarriers by the SDHCEC was increased with the increase in liquid lipid loading. The ex vivo fluorescence imaging of the ocular tissues indicated that the liquid lipid incorporation could improve the ocular retention and penetration of ocular therapeutics. No alternation was macroscopically observed in vivo after ocular surface exposure to nanocarriers. These results indicated that NLC was a biocompatible and potential nanocarrier for ocular drug delivery enhancement.

  14. Membrane lipids protected from oxidation by red wine tannins: a proton NMR study.

    Science.gov (United States)

    Furlan, Aurélien L; Jobin, Marie-Lise; Buchoux, Sébastien; Grélard, Axelle; Dufourc, Erick J; Géan, Julie

    2014-12-01

    Dietary polyphenols widespread in vegetables and beverages like red wine and tea have been reported to possess antioxidant properties that could have positive effects on human health. In this study, we propose a new in situ and non-invasive method based on proton liquid-state nuclear magnetic resonance (NMR) to determine the antioxidant efficiency of red wine tannins on a twice-unsaturated phospholipid, 1,2-dilinoleoyl-sn-glycero-3-phosphocholine (DLiPC), embedded in a membrane model. Four tannins were studied: (+)-catechin (C), (-)-epicatechin (EC), (-)-epicatechin gallate (ECG), and (-)-epigallocatechin gallate (EGCG). The lipid degradation kinetics was determined by measuring the loss of the bis-allylic protons during oxidation induced by a radical initiator, 2,2'-Azobis(2-methylpropionamidine) dihydrochloride (AAPH). The antioxidant efficiency, i.e. the ability of tannins to slow down the lipid oxidation rate, was shown to be higher for galloylated tannins, ECG and EGCG. Furthermore, the mixture of four tannins was more efficient than the most effective tannin, EGCG, demonstrating a synergistic effect. To better understand the antioxidant action mechanism of polyphenols on lipid membranes, the tannin location was investigated by NMR and molecular dynamics. A correlation between antioxidant action of tannins and their location at the membrane interface (inserted at the glycerol backbone level) could thus be established. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  15. Heart, lipids and hormones

    Directory of Open Access Journals (Sweden)

    Peter Wolf

    2017-05-01

    Full Text Available Cardiovascular disease is the leading cause of death in general population. Besides well-known risk factors such as hypertension, impaired glucose tolerance and dyslipidemia, growing evidence suggests that hormonal changes in various endocrine diseases also impact the cardiac morphology and function. Recent studies highlight the importance of ectopic intracellular myocardial and pericardial lipid deposition, since even slight changes of these fat depots are associated with alterations in cardiac performance. In this review, we overview the effects of hormones, including insulin, thyroid hormones, growth hormone and cortisol, on heart function, focusing on their impact on myocardial lipid metabolism, cardiac substrate utilization and ectopic lipid deposition, in order to highlight the important role of even subtle hormonal changes for heart function in various endocrine and metabolic diseases.

  16. Omega-3 fatty acids, lipids, and apoE lipidation in Alzheimer's disease: a rationale for multi-nutrient dementia prevention.

    Science.gov (United States)

    Grimm, Marcus O W; Michaelson, Daniel M; Hartmann, Tobias

    2017-11-01

    In the last decade, it has become obvious that Alzheimer's disease (AD) is closely linked to changes in lipids or lipid metabolism. One of the main pathological hallmarks of AD is amyloid-β (Aβ) deposition. Aβ is derived from sequential proteolytic processing of the amyloid precursor protein (APP). Interestingly, both, the APP and all APP secretases are transmembrane proteins that cleave APP close to and in the lipid bilayer. Moreover, apoE4 has been identified as the most prevalent genetic risk factor for AD. ApoE is the main lipoprotein in the brain, which has an abundant role in the transport of lipids and brain lipid metabolism. Several lipidomic approaches revealed changes in the lipid levels of cerebrospinal fluid or in post mortem AD brains. Here, we review the impact of apoE and lipids in AD, focusing on the major brain lipid classes, sphingomyelin, plasmalogens, gangliosides, sulfatides, DHA, and EPA, as well as on lipid signaling molecules, like ceramide and sphingosine-1-phosphate. As nutritional approaches showed limited beneficial effects in clinical studies, the opportunities of combining different supplements in multi-nutritional approaches are discussed and summarized. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

  17. Radiation-induced lipid peroxidation: influence of oxygen concentration and membrane lipid composition

    International Nuclear Information System (INIS)

    Wolters, H.; Tilburg, C.A.M. van; Konings, A.W.T.

    1987-01-01

    Radiation -induced lipid peroxidation phospholipid liposomes was investigated in terms of its dependence on lipid composition and oxygen concentration. Non-peroxidizable lipid incorporated in the liposomes reduced the rate of peroxidation of the peroxidizable phospholipid acyl chains, possibly by restricting the length of chain reactions. The latter effect is believed to be caused by interference of the non-peroxidizable lipids in the bilayer. At low oxygen concentration lipid peroxidation was reduced. The cause of this limited peroxidation may be a reduced number of radical initiation reactions possibly involving oxygen-derived superoxide radicals. Killing of proliferating mammalian cells, irradiated at oxygen concentrations ranging from 0 to 100%, appeared to be independent of the concentration of peroxidizable phospholipids in the cell membranes. This indicates that lipid peroxidation is not the determining process in radiation-induced reproductive cell death. (author)

  18. In vitro study of interaction of synaptic vesicles with lipid membranes

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, S K; Castorph, S; Salditt, T [Institute for X-ray Physics, University of Goettingen, 37077 Goettingen (Germany); Konovalov, O [European Synchrotron Radiation Facility, 38043 Grenoble Cedex (France); Jahn, R; Holt, M, E-mail: sghosh1@gwdg.d, E-mail: mholt@gwdg.d, E-mail: tsaldit@gwdg.d [Department of Neurobiology, Max Planck Institute for Biophysical Chemistry, 37077 Goettingen (Germany)

    2010-10-15

    The fusion of synaptic vesicles (SVs) with the plasma membrane in neurons is a crucial step in the release of neurotransmitters, which are responsible for carrying signals between nerve cells. While many of the molecular players involved in this fusion process have been identified, a precise molecular description of their roles in the process is still lacking. A case in point is the plasma membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP{sub 2}). Although PIP{sub 2} is known to be essential for vesicle fusion, its precise role in the process remains unclear. We have re-investigated the role of this lipid in membrane structure and function using the complementary experimental techniques of x-ray reflectivity, both on lipid monolayers at an air-water interface and bilayers on a solid support, and grazing incidence x-ray diffraction on lipid monolayers. These techniques provide unprecedented access to structural information at the molecular level, and detail the profound structural changes that occur in a membrane following PIP{sub 2} incorporation. Further, we also confirm and extend previous findings that the association of SVs with membranes is enhanced by PIP{sub 2} incorporation, and reveal the structural changes that underpin this phenomenon. Further, the association is further intensified by a physiologically relevant amount of Ca{sup 2+} ions in the subphase of the monolayer, as revealed by the increase in interfacial pressure seen with the lipid monolayer system. Finally, a theoretical calculation concerning the products arising from the fusion of these SVs with proteoliposomes is presented, with which we aim to illustrate the potential future uses of this system.

  19. A Coarse Grained Model for a Lipid Membrane with Physiological Composition and Leaflet Asymmetry.

    Directory of Open Access Journals (Sweden)

    Satyan Sharma

    Full Text Available The resemblance of lipid membrane models to physiological membranes determines how well molecular dynamics (MD simulations imitate the dynamic behavior of cell membranes and membrane proteins. Physiological lipid membranes are composed of multiple types of phospholipids, and the leaflet compositions are generally asymmetric. Here we describe an approach for self-assembly of a Coarse-Grained (CG membrane model with physiological composition and leaflet asymmetry using the MARTINI force field. An initial set-up of two boxes with different types of lipids according to the leaflet asymmetry of mammalian cell membranes stacked with 0.5 nm overlap, reliably resulted in the self-assembly of bilayer membranes with leaflet asymmetry resembling that of physiological mammalian cell membranes. Self-assembly in the presence of a fragment of the plasma membrane protein syntaxin 1A led to spontaneous specific positioning of phosphatidylionositol(4,5bisphosphate at a positively charged stretch of syntaxin consistent with experimental data. An analogous approach choosing an initial set-up with two concentric shells filled with different lipid types results in successful assembly of a spherical vesicle with asymmetric leaflet composition. Self-assembly of the vesicle in the presence of the synaptic vesicle protein synaptobrevin 2 revealed the correct position of the synaptobrevin transmembrane domain. This is the first CG MD method to form a membrane with physiological lipid composition as well as leaflet asymmetry by self-assembly and will enable unbiased studies of the incorporation and dynamics of membrane proteins in more realistic CG membrane models.

  20. Molecular dynamics study of lipid bilayers modeling the plasma membranes of mouse hepatocytes and hepatomas.

    Science.gov (United States)

    Andoh, Yoshimichi; Aoki, Noriyuki; Okazaki, Susumu

    2016-02-28

    Molecular dynamics (MD) calculations of lipid bilayers modeling the plasma membranes of normal mouse hepatocytes and hepatomas in water have been performed under physiological isothermal-isobaric conditions (310.15 K and 1 atm). The changes in the membrane properties induced by hepatic canceration were investigated and were compared with previous MD calculations included in our previous study of the changes in membrane properties induced by murine thymic canceration. The calculated model membranes for normal hepatocytes and hepatomas comprised 23 and 24 kinds of lipids, respectively. These included phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, sphingomyelin, lysophospholipids, and cholesterol. We referred to previously published experimental values for the mole fraction of the lipids adopted in the present calculations. The calculated structural and dynamic properties of the membranes such as lateral structure, order parameters, lateral self-diffusion constants, and rotational correlation times all showed that hepatic canceration causes plasma membranes to become more ordered laterally and less fluid. Interestingly, this finding contrasts with the less ordered structure and increased fluidity of plasma membranes induced by thymic canceration observed in our previous MD study.

  1. Effect of Difference in Fatty Acid Chain Lengths of Medium- Chain Lipids on Lipid/Surfactant/Water Phase Diagrams and Drug Solubility

    Directory of Open Access Journals (Sweden)

    Hetal N. Prajapati

    2011-09-01

    Full Text Available Lipids consisting of medium chain fatty acids are commonly used in the development of lipid-based selfemulsifying and self-microemulsifying drug delivery systems. However, no systematic approach to selecting one lipid over another has been reported in the literature. In this study, propylene glycol (PG monoester (PG monocaprylate, Capmul PG-8® and PG diester (PG dicaprylocaprate, Captex 200P® of C8-fatty acids were compared with PG monoester (PG monolaurate, Capmul PG-12® and PG diester (PG dilaurate, Capmul PG-2L® of C12-fatty acids with respect to their phase diagrams, and especially for their ability to form microemulsions in the presence of a common surfactant, Cremophor EL®, and water. The solubility of two model drugs, danazol and probucol, in the lipids and lipid/surfactant mixtures were also compared. The effect of the chain length of medium-chain fatty acids (C8 versus C12 on the phase diagrams of the lipids was minimal. Both shorter and longer chain lipids formed essentially similar microemulsion and emulsion regions in the presence of Cremophor EL® and water, although the C12-fatty acid esters formed larger gel regions in the phase diagrams than the C8-fatty acid esters. When monoesters were mixed with their respective diesters at 1:1 ratios, larger microemulsion regions with lower lipid particle sizes were observed compared to those obtained with individual lipids alone. While the solubility of both danazol and probucol increased greatly in all lipids studied, compared to their aqueous solubility, the solubility in C12-fatty acid esters was found to be lower than in C8-fatty acid esters when the lipids were used alone. This difference in solubility due to the difference in fatty acid chain length, practically disappeared when the lipids were combined with the surfactant.

  2. Study of water diffusion on single-supported bilayer lipid membranes by quasielastic neutron scattering

    DEFF Research Database (Denmark)

    Bai, M.; Miskowiec, A.; Hansen, F. Y.

    2012-01-01

    High-energy-resolution quasielastic neutron scattering has been used to elucidate the diffusion of water molecules in proximity to single bilayer lipid membranes supported on a silicon substrate. By varying sample temperature, level of hydration, and deuteration, we identify three different types...... of diffusive water motion: bulk-like, confined, and bound. The motion of bulk-like and confined water molecules is fast compared to those bound to the lipid head groups (7-10 H2O molecules per lipid), which move on the same nanosecond time scale as H atoms within the lipid molecules. Copyright (C) EPLA, 2012...

  3. Rab32 is important for autophagy and lipid storage in Drosophila.

    Directory of Open Access Journals (Sweden)

    Chao Wang

    Full Text Available Lipids are essential components of all organisms. Within cells, lipids are mainly stored in a specific type of organelle, called the lipid droplet. The molecular mechanisms governing the dynamics of lipid droplets have been little explored. The protein composition of lipid droplets has been analyzed in numerous proteomic studies, and a large number of lipid droplet-associated proteins have been identified, including Rab small GTPases. Rab proteins are known to participate in many intracellular membranous events; however, their exact role in lipid droplets is largely unexplored. Here we systematically investigate the roles of Drosophila Rab family proteins in lipid storage in the larval adipose tissue, fat body. Rab32 and several other Rabs were found to affect the size of lipid droplets as well as lipid levels. Further studies showed that Rab32 and Rab32 GEF/Claret may be involved in autophagy, consequently affecting lipid storage. Loss-of-function mutants of several components in the autophagy pathway result in similar effects on lipid storage. These results highlight the potential functions of Rabs in regulating lipid metabolism.

  4. Blood lipids and prostate cancer

    DEFF Research Database (Denmark)

    Bull, Caroline J; Bonilla, Carolina; Holly, Jeff M P

    2016-01-01

    Genetic risk scores were used as unconfounded instruments for specific lipid traits (Mendelian randomization) to assess whether circulating lipids causally influence prostate cancer risk. Data from 22,249 prostate cancer cases and 22,133 controls from 22 studies within the international PRACTICAL...... into logistic regression models to estimate the presence (and direction) of any causal effect of each lipid trait on prostate cancer risk. There was weak evidence for an association between the LDL genetic score and cancer grade: the odds ratio (OR) per genetically instrumented standard deviation (SD) in LDL.......95, 3.00; P = 0.08). The rs12916-T variant in 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) was inversely associated with prostate cancer (OR: 0.97; 95% CI: 0.94, 1.00; P = 0.03). In conclusion, circulating lipids, instrumented by our genetic risk scores, did not appear to alter prostate cancer risk...

  5. Lipids, lipid droplets and lipoproteins in their cellular context; an ultrastructural approach

    NARCIS (Netherlands)

    Mesman, R.J.

    2013-01-01

    Lipids are essential for cellular life, functioning either organized as bilayer membranes to compartmentalize cellular processes, as signaling molecules or as metabolic energy storage. Our current knowledge on lipid organization and cellular lipid homeostasis is mainly based on biochemical data.

  6. Increasing the extraction efficiency of algal lipid for biodiesel ...

    African Journals Online (AJOL)

    Various studies have been conducted recently using microalgal system for the production of algal lipid for biodiesel production. This study aimed at increasing the extraction efficiency of algal lipid from Chlorella sp. by the application of Chlorella viruses. The calorific value of lipid from Chlorella sp. has been reported to be ...

  7. Detection of lipid peroxidation in frozen-thawed avian spermatozoa using C(11)-BODIPY(581/591).

    Science.gov (United States)

    Partyka, Agnieszka; Lukaszewicz, Ewa; Niżański, Wojciech; Twardoń, Jan

    2011-06-01

    The aim of this study was to perform flow cytometric analysis of C11-BODIPY581/591 oxidation in fowl and geese sperm as a marker for membrane lipid peroxidation (LPO) and to establish if the cryopreservation process would make sperm membranes more susceptible to oxidative stress. The experiment was carried out on 10 meat type line Flex roosters and 10 White Koluda® geese. The semen was collected two times a week, by dorso-abdominal massage method and pooled from 10 individuals of each species. Fowl semen samples were subjected to cryopreservation using the "pellet" method and Dimethylacetamide (DMA) as a cryoprotectant. Geese semen samples were cryopreserved in plastic straws in a programmable freezing unit with Dimethyloformamide (DMF) as the cryoprotectant. A fluorescent lipid probe C11-BODIPY581/591 provided with two double bonds that are oxidized during their contact with ROS, was used for the purpose of the assessment of the LPO in freshly diluted semen samples and frozen-thawed semen samples. This probe changes its color according to its state (non peroxidized: red; peroxidized: green). Flow cytometric analysis was used to monitor these changes. The White Koluda® geese fresh semen had a higher level of LPO than the Flex fresh semen (P > 0.01). The cryopreservation of fowl semen significantly (P > 0.01) increased the percentage of live and dead spermatozoa with lipid peroxidation. In frozen-thawed semen of White Koluda® geese the percentage of live spermatozoa with LPO significantly decreased (P > 0.05) whereas significantly (P > 0.01) higher level of dead cells with LPO was observed. There were significant differences between the two studied species. After thawing, the percentage of live and dead spermatozoa with lipid peroxidation was higher in fowl semen than in geese semen (P > 0.01). In conclusion, our data clearly indicate the existence of species specific differences in susceptibility of spermatozoa to the oxidation of PUFAs in the cell membranes

  8. Exogenous lipid pneumonia

    International Nuclear Information System (INIS)

    Bernasconi, A.; Gavelli, G.; Zompatori, M.; Galleri, C.; Zanasi, A.; Fabbri, M.; Bazzocchi, F.

    1988-01-01

    Exogenous lipid pneumonia (ELP) is caused by the aspiration of animal, vegetal or, more often, mineral oils. Even though it may also be acute, ELP is most frequently a chronic disease, affecting people with predisposing factors, such as neuromuscular disorders, structural abnormalities and so on; very often exogenous lipid pneumonia is found in tracheotomized patients. The pathology of lipid pneumonia is a chronic inflammatory process evolving in foreign-body-like reaction, and eventually in ''end-stage lung'' condition. Clinically, most patients are asymptomatic; few cases only present with cough, dyspnea and chest pain. Eight cases of ELP, studied over the past 3 years, are described in this paper. All the patients were examined by chest radiographs and standard tomograms; 3 patients underwent CT. X-ray features were mono/bilateral consolidation of the lower zones, with air bronchogram and variable reduction in volume. CT density was not specific for fat tissue. In all cases the diagnosis was confirmed at biopsy. In 5 patients, followed for at least one year, clinical-radiological features showed no change. Thus, complications of ELP (especially malignant evolution) could be excluded. The authors conclude that lipid pneumonia must be considered in differential diagnosis of patients with history of usage of oils and compatible X-ray findings. The usefulness of an accurate follow-up is stressed

  9. Lateral pressure profiles in lipid monolayers

    NARCIS (Netherlands)

    Baoukina, Svetlana; Marrink, Siewert J.; Tieleman, D. Peter

    2010-01-01

    We have used molecular dynamics simulations with coarse-grained and atomistic models to study the lateral pressure profiles in lipid monolayers. We first consider simple oil/air and oil/water interfaces, and then proceed to lipid monolayers at air/water and oil/water interfaces. The results are

  10. Effects of nutritional conditions on lipid production by cyanobacteria.

    Science.gov (United States)

    Cordeiro, Raquel S; Vaz, Izabela C D; Magalhães, Sérgia M S; Barbosa, Francisco A R

    2017-01-01

    The present study evaluated the effects of the culturing media and the levels of nitrogen and phosphorus on the growth, biomass productivity and lipid production of four species of Microcystis (M. novacekii, M. aeruginosa, M panniformis and M. protocystis). The lipid extract was obtained by refluxing with dichloromethane (Soxhlet). The biomass and biomass productivity yields were maximized with ASM-1 medium treatment enriched with nitrogen and/or phosphorus (0.25-0.65 g/L and 25-50.7 mg/L d-1, respectively). The lipid extract yields from M. panniformis and M. novacekii were inversely correlated with the concentration of nitrogen and directly correlated with the concentration of phosphorus (35.8 % and 31.7 %). The lipid extract yield from M. aeruginosa was inversely correlated with the nutrient concentration (23.3 %). M. protocystis exhibited a higher lipid content in the control medium (41.5 %) than in the nitrogen-enriched media. The recorded results show that a nutrient-poor culture medium favours cell growth and stimulates lipid accumulation, which directly affects the cost of cultivation by reducing nutrient consumption. All studied species may serve as biomass sources for biodiesel production, although M. protocystis exhibited the highest lipid production. Further studies are necessary to determine the composition of the recorded lipid extract.

  11. Effects of nutritional conditions on lipid production by cyanobacteria

    Directory of Open Access Journals (Sweden)

    RAQUEL S. CORDEIRO

    Full Text Available ABSTRACT The present study evaluated the effects of the culturing media and the levels of nitrogen and phosphorus on the growth, biomass productivity and lipid production of four species of Microcystis (M. novacekii, M. aeruginosa, M panniformis and M. protocystis. The lipid extract was obtained by refluxing with dichloromethane (Soxhlet. The biomass and biomass productivity yields were maximized with ASM-1 medium treatment enriched with nitrogen and/or phosphorus (0.25-0.65 g/L and 25-50.7 mg/L d-1, respectively. The lipid extract yields from M. panniformis and M. novacekii were inversely correlated with the concentration of nitrogen and directly correlated with the concentration of phosphorus (35.8 % and 31.7 %. The lipid extract yield from M. aeruginosa was inversely correlated with the nutrient concentration (23.3 %. M. protocystis exhibited a higher lipid content in the control medium (41.5 % than in the nitrogen-enriched media. The recorded results show that a nutrient-poor culture medium favours cell growth and stimulates lipid accumulation, which directly affects the cost of cultivation by reducing nutrient consumption. All studied species may serve as biomass sources for biodiesel production, although M. protocystis exhibited the highest lipid production. Further studies are necessary to determine the composition of the recorded lipid extract.

  12. Primary Open-Angle Glaucoma and Serum Lipids

    Directory of Open Access Journals (Sweden)

    Suzana Pavljašević

    2009-02-01

    Full Text Available The aim of this paper was to prove the relation between serum lipid values (cholesterol, trig- lyceride, low density cholesterol, high density cholesterol and primary open -angle glaucoma. The study includes two patient groups: 50 patients with primary open-angle glaucoma and 50 patients without this disease. However, all 100 patients were tested for serum lipid values. The research covered a period of six months (from May to December 2007.. Primary open-angle glaucoma was diagnosed with intraocular pressure values (between 20,1 and 25,6 mm Hg measured with Schiotz tonometry. The visual field changes were confirmed with Goldmann perimetry. The gonioscopies were done for diagnosis confirmation. The serum lipid values were confirmed with enzymatic colorimetry in vitro method. U-test (Mann-Witney-Wilcox test and t-test, as nonparametric tests, were used for statistical evaluations. The cholesterol mean value in the test group was 6,14 mol/dm1 (3,20-8,10 mol/dm3 whereas in the control group it was 5,96 mol/dm3 (2,70-8,80 mol/dm3. U-test was with negative ranks (z=-0,83 AS=0,678. The triglyceride mean value in the test group was 2,38 mol/dm3 (0,84-11,73 mol/m3 and in the control group it was 2,04 mol/dm3 (0,63-5,89 mol/dm3. U-test was with positive ranks (z=0,950 AS=0,342. High density cholesterol was average in the test group with 1,45 mol/dm3 (0,71-3,40 mol/dm3 and in the control group 1,40 mol/m3 (0,80-3,20 mol/dm3. Low density cholesterol in the test group was 3,98 mol/m3 (1,82-6,49 mol/m3 and in the control group 4,08 mol/m3 (2,69-5,69 mol/m3. These results had positive ranks according to U-test. Serum lipid values could be one of predictable factors in primary open-angle glaucoma diagnosis. Due to the patient age, cholesterol values, as common factors in primary open-angle glaucoma and atherosclerosis genesis, could be concern in the same aetiology based on dyslipidaemia as well.

  13. Efficacy of a shower cream and a lotion with skin-identical lipids in healthy subjects with atopic dry skin.

    Science.gov (United States)

    Berardesca, Enzo; Mortillo, Susan; Cameli, Norma; Ardigo, Marco; Mariano, Maria

    2018-05-10

    Atopic dermatitis is a chronic, pruritic inflammatory skin disease that adversely affects quality of life. The current study evaluates the efficacy of a shower cream and a lotion, each with skin-identical lipids and emollients, in the treatment of atopic dry skin of subjects with a history of atopic condition. In all, 40 healthy females with clinically dry skin on the lower legs were enrolled in the study and underwent 4 weeks of daily use of the shower cream and 2 additional weeks of both the shower cream and the body lotion. Subjects were evaluated at day 0, week 4, and week 6. Skin barrier function was assessed by Tewameter ® , skin hydration by Corneometer ® , smoothness and desquamation by Visioscan ® , and stratum corneum architecture by reflectance confocal microscopy (RCM). The investigator assessed the degree of dryness, roughness, redness, cracks, tingling and itch, and subjective self-assessment evaluated the perception of skin soothing, smoothness, and softness. Skin barrier function and skin moisture maintenance were significantly improved using the shower cream. The lotion with physiological lipids, together with the shower cream, also improved skin barrier function and moisture. Both the shower cream and the body lotion reduced clinical dryness, roughness, redness, cracks, tingling and itch, according to the dermatologist, and increased soothing, smoothness, and softness, according to the subjects of the study. The combination of a shower cream and a lotion with physiological lipids efficiently restores skin barrier function and increases skin hydration, becoming an effective skin-care option for patients with atopic dry skin. © 2018 Wiley Periodicals, Inc.

  14. Multiple linear stepwise regression of liver lipid levels: proton MR spectroscopy study in vivo at 3.0 T

    International Nuclear Information System (INIS)

    Xu Li; Liang Changhong; Xiao Yuanqiu; Zhang Zhonglin

    2010-01-01

    Objective: To analyze the correlations between liver lipid level determined by liver 3.0 T 1 H-MRS in vivo and influencing factors using multiple linear stepwise regression. Methods: The prospective study of liver 1 H-MRS was performed with 3.0 T system and eight-channel torso phased-array coils using PRESS sequence. Forty-four volunteers were enrolled in this study. Liver spectra were collected with a TR of 1500 ms, TE of 30 ms, volume of interest of 2 cm×2 cm×2 cm, NSA of 64 times. The acquired raw proton MRS data were processed by using a software program SAGE. For each MRS measurement, using water as the internal reference, the amplitude of the lipid signal was normalized to the sum of the signal from lipid and water to obtain percentage lipid within the liver. The statistical description of height, weight, age and BMI, Line width and water suppression were recorded, and Pearson analysis was applied to test their relationships. Multiple linear stepwise regression was used to set the statistical model for the prediction of Liver lipid content. Results: Age (39.1±12.6) years, body weight (64.4±10.4) kg, BMI (23.3±3.1) kg/m 2 , linewidth (18.9±4.4) and the water suppression (90.7±6.5)% had significant correlation with liver lipid content (0.00 to 0.96%, median 0.02%), r were 0.11, 0.44, 0.40, 0.52, -0.73 respectively (P<0.05). But only age, BMI, line width, and the water suppression entered into the multiple linear regression equation. Liver lipid content prediction equation was as follows: Y= 1.395 - (0.021×water suppression) + (0.022×BMI) + (0.014×line width) - (0.004×age), and the coefficient of determination was 0. 613, corrected coefficient of determination was 0.59. Conclusion: The regression model fitted well, since the variables of age, BMI, width, and water suppression can explain about 60% of liver lipid content changes. (authors)

  15. Influence of encapsulated functional lipids on crystal structure and chemical stability in solid lipid nanoparticles: Towards bioactive-based design of delivery systems.

    Science.gov (United States)

    Salminen, Hanna; Gömmel, Christina; Leuenberger, Bruno H; Weiss, Jochen

    2016-01-01

    We investigated the influence of physicochemical properties of encapsulated functional lipids--vitamin A, β-carotene and ω-3 fish oil--on the structural arrangement of solid lipid nanoparticles (SLN). The relationship between the crystal structure and chemical stability of the incorporated bioactive lipids was evaluated with different emulsifier compositions of a saponin-rich, food-grade Quillaja extract alone or combined with high-melting or low-melting lecithins. The major factors influencing the structural arrangement and chemical stability of functional lipids in solid lipid dispersions were their solubility in the aqueous phase and their crystallization temperature in relation to that of the carrier lipid. The results showed that the stabilization of the α-subcell crystals in the lattice of the carrier lipid is a key parameter for forming stable solid lipid dispersions. This study contributes to a better understanding of SLN as a function of the bioactive lipid. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Evaluation of a pharmacist-managed lipid clinic that uses point-of-care lipid testing.

    Science.gov (United States)

    Gerrald, Katherine R; Dixon, Dave L; Barnette, Debra J; Williams, Virginia G

    2010-01-01

    Hyperlipidemia is a significant, modifiable risk factor for developing coronary heart disease. Low-density lipoprotein cholesterol (LDL-C) goal achievement has improved overall, but many high-risk patients remain above the desired LDL-C goals. Published data have demonstrated the ability of pharmacist-managed lipid clinics to improve lipid management in a variety of clinical settings. This observational analysis aimed to report the impact of a newly developed hospital-based, outpatient lipid clinic by the use of point-of-care testing on LDL-C goal attainment. A retrospective, observational analysis was conducted from February 2007 to December 2008. The primary outcome measure was the change in the proportion of patients who achieved their LDL-C goal at the end of the observation period compared with baseline. A total of 81 patients met study inclusion criteria. Mean duration of follow-up was 9.0 ± 4.9 (SD) months. At the end of the observation period, 82.9% of patients achieved their LDL-C goal compared with 55.3% at baseline (P used point-of-care testing to obtain lipid results for making therapy adjustments during the face-to-face visit. Copyright © 2010 National Lipid Association. Published by Elsevier Inc. All rights reserved.

  17. Evaluation of percutaneous absorption of the repellent diethyltoluamide and the sunscreen ethylhexyl p-methoxycinnamate-loaded solid lipid nanoparticles: an in-vitro study.

    Science.gov (United States)

    Puglia, Carmelo; Bonina, Francesco; Castelli, Francesco; Micieli, Dorotea; Sarpietro, Maria Grazia

    2009-08-01

    Diethyltoluamide and ethylhexyl p-methoxycinnamate (OMC) are two active ingredients in insect repellent and sunscreen products, respectively. The concurrent application of these two substances often increases their systemic absorption, compromising the safety and efficiency of the cosmetic product. In this study, diethyltoluamide and OMC were incorporated into solid lipid nanoparticles, a colloidal drug delivery system, to reduce percutaneous absorption and avoid toxic effects and also maintain the efficacy of the two active compounds on the skin surface for a long duration. Solid lipid nanoparticles were prepared based on an ultrasonication technique and characterized by differential scanning calorimetry (DSC) analyses. In-vitro studies determined the percutaneous absorption of diethyltoluamide and OMC. DSC data carried out on unloaded and diethyltoluamide- and/or OMC-loaded solid lipid nanoparticles highlighted that diethyltoluamide and OMC modified the temperature and the enthalpy change associated to the calorimetric peak of solid lipid nanoparticles. The concurrent presence of the two compounds in the solid lipid nanoparticles caused a synergic effect, indicating that the lipid matrix of nanoparticles guaranteed a high encapsulation of both diethyltoluamide and OMC. Results from the in-vitro study demonstrated that the particles were able to reduce the skin permeation of the two cosmetic ingredients in comparison with an oil-in-water emulsion. This study has provided supplementary evidence as to the potential of lipid nanoparticles as carriers for topical administration of cosmetic active compounds.

  18. Apolipoprotein gene involved in lipid metabolism

    Science.gov (United States)

    Rubin, Edward; Pennacchio, Len A.

    2007-07-03

    Methods and materials for studying the effects of a newly identified human gene, APOAV, and the corresponding mouse gene apoAV. The sequences of the genes are given, and transgenic animals which either contain the gene or have the endogenous gene knocked out are described. In addition, single nucleotide polymorphisms (SNPs) in the gene are described and characterized. It is demonstrated that certain SNPs are associated with diseases involving lipids and triglycerides and other metabolic diseases. These SNPs may be used alone or with SNPs from other genes to study individual risk factors. Methods for intervention in lipid diseases, including the screening of drugs to treat lipid-related or diabetic diseases are also disclosed.

  19. Effect of temperature and pH on the lipid photoperoxidation and the structural state of erythrocyte membranes

    International Nuclear Information System (INIS)

    Roshchupkin, D.I.; Pelenitsyn, A.B.; Vladimirov, Yu.A.

    1978-01-01

    The degree of lipid photoperoxidation in erythrocytes (the amount of TBA-active products accumulated under the given dose of ultraviolet irradiation at 254 nm) increased abruptly with temperature in the interval 12 - 20 0 C, then it increased more slowly and later on passed over the maximum at about 30 - 32 0 C. Apparently, the degree of lipid photoperoxidation can serve as a sensitive index of lipid structural state. Using a method of modelling of erythrocyte membranes by liposomes of different chemical content, it was shown that under temperature changes in physiological limits the lipids of erythrocyte membranes undergo at least two structural transformations. The first might be a change in the relative position of cholesterol and phospholipids. The second is followed by the enhancement of membrane antioxidant activity. The degree of lipid photoperoxidation in erythrocytes grows with increasing pH from 6 to 8 according to S-shaped curve with middle point at pH 7.0. This effect can be attributed to structural transformation of membrane lipid zone associated with ionization of membrane protein hystidine. The swelling of erythrocytes in hypotonic medium also leads to structural transformation of lipid zone. (author)

  20. Lipid exchange by ultracentrifugation

    DEFF Research Database (Denmark)

    Drachmann, Nikolaj Düring; Olesen, Claus

    2014-01-01

    , and the complex interplay between the lipids and the P-type ATPases are still not well understood. We here describe a robust method to exchange the majority of the lipids surrounding the ATPase after solubilisation and/or purification with a target lipid of interest. The method is based on an ultracentrifugation...... step, where the protein sample is spun through a dense buffer containing large excess of the target lipid, which results in an approximately 80-85 % lipid exchange. The method is a very gently technique that maintains protein folding during the process, hence allowing further characterization...

  1. An ER Protein Functionally Couples Neutral Lipid Metabolism on Lipid Droplets to Membrane Lipid Synthesis in the ER

    DEFF Research Database (Denmark)

    Markgraf, Daniel F; Klemm, Robin W; Junker, Mirco

    2014-01-01

    Eukaryotic cells store neutral lipids such as triacylglycerol (TAG) in lipid droplets (LDs). Here, we have addressed how LDs are functionally linked to the endoplasmic reticulum (ER). We show that, in S. cerevisiae, LD growth is sustained by LD-localized enzymes. When LDs grow in early stationary...... phase, the diacylglycerol acyl-transferase Dga1p moves from the ER to LDs and is responsible for all TAG synthesis from diacylglycerol (DAG). During LD breakdown in early exponential phase, an ER membrane protein (Ice2p) facilitates TAG utilization for membrane-lipid synthesis. Ice2p has a cytosolic...... and explain how cells switch neutral lipid metabolism from storage to consumption....

  2. The interaction of new piroxicam analogues with lipid bilayers--a calorimetric and fluorescence spectroscopic study.

    Science.gov (United States)

    Maniewska, Jadwiga; Szczęśniak-Sięga, Berenika; Poła, Andrzej; Sroda-Pomianek, Kamila; Malinka, Wiesław; Michalak, Krystyna

    2014-01-01

    The purpose of the present paper was to assess the ability of new piroxicam analogues to interact with the lipid bilayers. The results of calorimetric and fluorescence spectroscopic experiments of two new synthesized analogues of piroxicam, named PR17 and PR18 on the phase behavior of phospholipid bilayers and fluorescence quenching of fluorescent probes (Laurdan and Prodan), which molecular location within membranes is known with certainty, are shown in present work. The presented results revealed that, depending on the details of chemical structure, the studied compounds penetrated the lipid bilayers.

  3. Android and gynoid fat percentages and serum lipid levels in United States adults.

    Science.gov (United States)

    Min, Kyoung-Bok; Min, Jin-Young

    2015-03-01

    Accumulating evidence suggests that fat distribution is a better predictor of cardiovascular disease than body mass index (BMI). The aim of this study was to investigate the association of android and gynoid fat percentages with lipid profiles to determine whether android and/or gynoid fat percentages are associated with serum lipid levels. A population-based cross-sectional study. Five thousand six hundred and ninety-six adults (20 years and older) who participated in the National Health and Nutrition Examination Survey 2003-2006. The regional body composition in the android and gynoid regions was defined by dual energy X-ray absorptiometry (DXA). The estimation of lipid risk profiles included total cholesterol, high-density lipoprotein (HDL) -cholesterol, low-density lipoprotein (LDL) -cholesterol and triglycerides (TG). Regardless of gender, android and gynoid body fat percentages were positively and significantly correlated with BMI and waist circumference. After adjustment for age, ethnicity, education, smoking, alcohol consumption, dyslipidaemia and BMI, increases in android fat percentage were significantly associated with total cholesterol, TG and HDL cholesterol in males, and total cholesterol, HDL cholesterol and LDL cholesterol in females. The gynoid fat percentages showed a positive correlation with total cholesterol in males, whereas gynoid fat accumulation in females showed a favourable association with TG and HDL cholesterol. The observed associations differed according to ethnic groups. Our results suggest that regional fat distribution in the android and gynoid regions have different effects on lipid profiles, and that fat in the android region, rather than the gynoid region, may be an important factor in determining the risk of cardiovascular disease. © 2014 John Wiley & Sons Ltd.

  4. Affinity of serum apolipoproteins for lipid monolayers

    International Nuclear Information System (INIS)

    Ibdah, J.A.

    1987-01-01

    The effects of lipid composition and packing as well as the structure of the protein on the affinities of apolipoproteins for lipid monolayers have been investigated. The adsorption of 14 C-reductively methylated human apolipoproteins A-I and A-II at saturating subphase concentrations to monolayers prepared with synthetic lipids or lipoprotein surface lipids spread at various initial surface pressures has been studied. The adsorption of apolipoproteins is monitored by following the surface radioactivity using a gas flow counter and Wilhelmy plate, respectively. The physical states of the lipid monolayers are evaluated by measurement of the surface pressure-molecular area isotherms using a Langmuir-Adam surface balance. The probable helical regions in various apolipoproteins have been predicted using a secondary structure analysis computer program. The mean residue hydrophobicity and mean residue hydrophobic moment for the predicted helical segments have been calculated. The surface properties of synthetic peptides which are amphipathic helix analogs have been investigated at the air-water and lipid-water interfaces

  5. Lipid Bilayer Composition Affects Transmembrane Protein Orientation and Function

    Directory of Open Access Journals (Sweden)

    Katie D. Hickey

    2011-01-01

    Full Text Available Sperm membranes change in structure and composition upon ejaculation to undergo capacitation, a molecular transformation which enables spermatozoa to undergo the acrosome reaction and be capable of fertilization. Changes to the membrane environment including lipid composition, specifically lipid microdomains, may be responsible for enabling capacitation. To study the effect of lipid environment on proteins, liposomes were created using lipids extracted from bull sperm membranes, with or without a protein (Na+ K+-ATPase or -amylase. Protein incorporation, function, and orientation were determined. Fluorescence resonance energy transfer (FRET confirmed protein inclusion in the lipid bilayer, and protein function was confirmed using a colourometric assay of phosphate production from ATP cleavage. In the native lipid liposomes, ATPase was oriented with the subunit facing the outer leaflet, while changing the lipid composition to 50% native lipids and 50% exogenous lipids significantly altered this orientation of Na+ K+-ATPase within the membranes.

  6. A study of the enhanced sensitizing capacity of a contact allergen in lipid vesicle formulations

    DEFF Research Database (Denmark)

    Simonsson, Carl; Madsen, Jakob Torp; Graneli, Annette

    2011-01-01

    , an indicator of a compounds sensitizing capacity, increased when RBITC was applied in lipid vesicles as compared to an ethanol:water (Et:W) solution. Micro-scale vesicles showed a slightly higher cell proliferative response compared to nano-scale vesicles. TPM imaging revealed that the vesicle formulations...... improved the skin penetration of RBITC compared to the Et:W solution. A strong fluorescent region in the stratum corneum and upper epidermis implies elevated association of RBITC to these skin layers when formulated in lipid vesicles. In conclusion, the results indicate that there could be an elevated risk...... of sensitization when haptens are delivered in vehicles containing lipid vesicles. Although the size of the vesicles seems to be of minor importance, further studies are needed before a more generalized conclusion can be drawn. It is likely that the enhanced sensitizing capacity is a consequence of the improved...

  7. Altered lipid composition and enhanced lipid production in green microalga by introduction of brassica diacylglycerol acyltransferase 2.

    Science.gov (United States)

    Ahmad, Irshad; Sharma, Anil K; Daniell, Henry; Kumar, Shashi

    2015-05-01

    Higher lipid biosynthesis and accumulation are important to achieve economic viability of biofuel production via microalgae. To enhance lipid content, Chlamydomonas reinhardtii was genetically engineered with a key enzyme diacylglycerol acyltransferase (BnDGAT2) from Brassica napus, responsible for neutral lipid biosynthesis. The transformed colonies harbouring aph7 gene, screened on hygromycin-supplemented medium, achieved transformation frequency of ~120 ± 10 colonies/1 × 10(6) cells. Transgene integration and expression were confirmed by PCR, Southern blots, staining lipid droplets, proteins and spectro-fluorometric analysis of Nile red-stained cells. The neutral lipid is a major class (over 80% of total lipids) and most significant requirement for biodiesel production; this was remarkably higher in the transformed alga than the untransformed control. The levels of saturated fatty acids in the transformed alga decreased to about 7% while unsaturated fatty acids increased proportionately when compared to wild type cells. Polyunsaturated fatty acids, especially α-linolenic acid, an essential omega-3 fatty acid, were enhanced up to 12% in the transformed line. Nile red staining confirmed formation of a large number of lipid globules in the transformed alga. Evaluation of long-term stability and vitality of the transgenic alga revealed that cryopreservation produced significantly higher quantity of lipid than those maintained continuously over 128 generations on solid medium. The overexpression of BnDGAT2 significantly altered the fatty acids profile in the transformed alga. Results of this study offer a valuable strategy of genetic manipulation for enhancing polyunsaturated fatty acids and neutral lipids for biofuel production in algae. © 2014 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  8. GABA interaction with lipids in organic medium

    International Nuclear Information System (INIS)

    Beltramo, D.; Kivatinitz, S.; Lassaga, E.; Arce, A.

    1987-01-01

    The interaction of 3 H-GABA and 14 C-glutamate with lipids in an aqueous organic partition system was studied. With this partition system 3 H-GABA and 14 C-glutamate were able to interact with sphingomyelin, sulfatide, phosphatidylcholine, phosphatidylserine, phosphatidylethanolamine and phosphatidic acid but not with cholesterol or ceramide. In an homogeneous aqueous medium the authors could not demonstrate any interaction between 3 H-GABA-lipids. The apparent dissociation constants (K/sub d/) for 3 H-GABA-lipids or 14 C-glutamate-lipids interactions inorganic medium were in the millimolar range and maximal charge between 3 and 7 moles of GABA or glutamate by mole of lipid. Amino acids such as glutamic acid, β-alanine and glycine displaced 3 H-GABA with the same potency as GABA itself; thus these results show that the interaction lacks pharmacological specificity. To detect this interaction lipid concentrations higher than 2 μM were required and in the partition system 3 H-GABA and lipid phosphorus were both concentrated at the interface. Therefore, lipids tested with a biphasic partition system do not fulfill the classical criteria for a neurotransmitter receptor at least not for GABA and glutamate. 15 references, 1 figure, 3 tables

  9. Bacterial S-layer protein coupling to lipids

    DEFF Research Database (Denmark)

    Weygand, M.; Wetzer, B.; Pum, D.

    1999-01-01

    structure before and after protein recrystallization shows minimal reorganization of the lipid chains. By contrast, the lipid headgroups show major rearrangements. For the B. sphaericus CCM2177 protein underneath DPPE monolayers, x-ray reflectivity data suggest that amino acid side chains intercalate......The coupling of bacterial surface (S)-layer proteins to lipid membranes is studied in molecular detail for proteins from Bacillus sphaericus CCM2177 and B. coagulans E38-66 recrystallized at dipalmitoylphosphatidylethanolamine (DPPE) monolayers on aqueous buffer. A comparison of the monolayer...... the lipid headgroups at least to the phosphate moieties, and probably further beyond. The number of electrons in the headgroup region increases by more than four per lipid. Analysis of the changes of the deduced electron density profiles in terms of a molecular interpretation shows...

  10. Analytical Raman spectroscopic study for discriminant analysis of different animal-derived feedstuff: Understanding the high correlation between Raman spectroscopy and lipid characteristics.

    Science.gov (United States)

    Gao, Fei; Xu, Lingzhi; Zhang, Yuejing; Yang, Zengling; Han, Lujia; Liu, Xian

    2018-02-01

    The objectives of the current study were to explore the correlation between Raman spectroscopy and lipid characteristics and to assess the potential of Raman spectroscopic methods for distinguishing the different sources of animal-originated feed based on lipid characteristics. A total of 105 lipid samples derived from five animal species have been analyzed by gas chromatography (GC) and FT-Raman spectroscopy. High correlations (r 2 >0.94) were found between the characteristic peak ratio of the Raman spectra (1654/1748 and 1654/1445) and the degree of unsaturation of the animal lipids. The results of FT-Raman data combined with chemometrics showed that the fishmeal, poultry, porcine and ruminant (bovine and ovine) MBMs could be well separated based on their lipid spectral characteristics. This study demonstrated that FT-Raman spectroscopy can mostly exhibit the lipid structure specificity of different species of animal-originated feed and can be used to discriminate different animal-originated feed samples. Copyright © 2017. Published by Elsevier Ltd.

  11. Do lipids shape the eukaryotic cell cycle?

    Science.gov (United States)

    Furse, Samuel; Shearman, Gemma C

    2018-01-01

    Successful passage through the cell cycle presents a number of structural challenges to the cell. Inceptive studies carried out in the last five years have produced clear evidence of modulations in the lipid profile (sometimes referred to as the lipidome) of eukaryotes as a function of the cell cycle. This mounting body of evidence indicates that lipids play key roles in the structural transformations seen across the cycle. The accumulation of this evidence coincides with a revolution in our understanding of how lipid composition regulates a plethora of biological processes ranging from protein activity through to cellular signalling and membrane compartmentalisation. In this review, we discuss evidence from biological, chemical and physical studies of the lipid fraction across the cell cycle that demonstrate that lipids are well-developed cellular components at the heart of the biological machinery responsible for managing progress through the cell cycle. Furthermore, we discuss the mechanisms by which this careful control is exercised. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  12. Effect of cadmium on lipid metabolism of brain. In vivo incorporation of labelled acetate into lipids

    Energy Technology Data Exchange (ETDEWEB)

    Gulati, S; Gill, K D; Nath, R

    1987-01-01

    The effect of early postnatal cadmium exposure on the in vivo incorporation of (1-/sup 14/C) sodium acetate into various lipid classes of the weanling rat brain was studied. A stimulated incorporation of the label was observed in total lipids, phospholipids, cholesterol, cerebrosides and sulphatides of the brain of Cd-exposed animals compared to controls.

  13. Interaction of lysozyme with a tear film lipid layer model: A molecular dynamics simulation study.

    Science.gov (United States)

    Wizert, Alicja; Iskander, D Robert; Cwiklik, Lukasz

    2017-12-01

    The tear film is a thin multilayered structure covering the cornea. Its outermost layer is a lipid film underneath of which resides on an aqueous layer. This tear film lipid layer (TFLL) is itself a complex structure, formed by both polar and nonpolar lipids. It was recently suggested that due to tear film dynamics, TFLL contains inhomogeneities in the form of polar lipid aggregates. The aqueous phase of tear film contains lachrymal-origin proteins, whereby lysozyme is the most abundant. These proteins can alter TFLL properties, mainly by reducing its surface tension. However, a detailed nature of protein-lipid interactions in tear film is not known. We investigate the interactions of lysozyme with TFLL in molecular details by employing coarse-grained molecular dynamics simulations. We demonstrate that lysozyme, due to lateral restructuring of TFLL, is able to penetrate the tear lipid film embedded in inverse micellar aggregates. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Effects of whole grain, fish and bilberries on serum metabolic profile and lipid transfer protein activities: a randomized trial (Sysdimet.

    Directory of Open Access Journals (Sweden)

    Maria Lankinen

    Full Text Available We studied the combined effects of wholegrain, fish and bilberries on serum metabolic profile and lipid transfer protein activities in subjects with the metabolic syndrome.Altogether 131 subjects (40-70 y, BMI 26-39 kg/m(2 with impaired glucose metabolism and features of the metabolic syndrome were randomized into three groups with 12-week periods according to a parallel study design. They consumed either: a wholegrain and low postprandial insulin response grain products, fatty fish 3 times a week, and bilberries 3 portions per day (HealthyDiet, b wholegrain and low postprandial insulin response grain products (WGED, or c refined wheat breads as cereal products (Control. Altogether 106 subjects completed the study. Serum metabolic profile was studied using an NMR-based platform providing information on lipoprotein subclasses and lipids as well as low-molecular-weight metabolites.There were no significant differences in clinical characteristics between the groups at baseline or at the end of the intervention. Mixed model analyses revealed significant changes in lipid metabolites in the HealthyDiet group during the intervention compared to the Control group. All changes reflected increased polyunsaturation in plasma fatty acids, especially in n-3 PUFAs, while n-6 and n-7 fatty acids decreased. According to tertiles of changes in fish intake, a greater increase of fish intake was associated with increased concentration of large HDL particles, larger average diameter of HDL particles, and increased concentrations of large HDL lipid components, even though total levels of HDL cholesterol remained stable.The results suggest that consumption of diet rich in whole grain, bilberries and especially fatty fish causes changes in HDL particles shifting their subclass distribution toward larger particles. These changes may be related to known protective functions of HDL such as reverse cholesterol transport and could partly explain the known protective

  15. Secular trends in lipid-lowering treatment and lipid levels after a first acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    Lena Björck

    2008-01-01

    Full Text Available Lena Björck1, Catharina Welin2, Annika Rosengren11Department of medicine, Sahlgrenska University Hospital/Östra, Göteborg, Sweden; 2Institute of Health and Care Sciences, the Sahlgrenska Academy at Göteborg University, Göteborg, SwedenBackground: The beneficial effects of statins were unequivocally demonstrated in the Scandinavian Simvastatin Survival Study (4S in 1994, leading to an increase in the use of lipid-lowering drugs. However, to what extent this translates into serum cholesterol levels in a real-life setting has not been systematically investigated.Objective: To estimate secular trends from 1994 to 2002 in blood lipid levels among unselected younger patients after a first acute myocardial infarction (AMI.Method: Descriptive single centre study using consecutive data collection in 781 patients (aged <65 years hospitalized with a first AMI during the period 1994–2002.Results: From 1994–2002, the use of lipid-lowering drugs increased from 10% to 94% for men and from 23% to 90% for women. In 1994, the mean serum cholesterol levels were 6.53 mmol/l in men and 6.32 mmol/l in women, decreasing to 4.31 mmol/l and 5.13 mmol/l in men and women, respectively, in 2002. Still, only 56% of the men and 35% of the women had total serum cholesterol levels <4.5 mmol/l in 2002.Conclusion: Despite a marked increase in lipid-lowering drug treatment in which there was an increase from about 10% in 1994 to more than 90% in 2002, current target levels of <4.5 mmol/l for serum cholesterol were not achieved in a significant proportion of post-AMI patients.Keywords: lipid levels, lipid-lowering medication, myocardial infarction, risk factors

  16. Homeoviscous adaptation and the regulation of membrane lipids

    DEFF Research Database (Denmark)

    Ernst, Robert; Ejsing, Christer S; Antonny, Bruno

    2016-01-01

    Biological membranes are complex and dynamic assemblies of lipids and proteins. Poikilothermic organisms including bacteria, fungi, reptiles, and fish do not control their body temperature and must adapt their membrane lipid composition in order to maintain membrane fluidity in the cold. This ada......Biological membranes are complex and dynamic assemblies of lipids and proteins. Poikilothermic organisms including bacteria, fungi, reptiles, and fish do not control their body temperature and must adapt their membrane lipid composition in order to maintain membrane fluidity in the cold....... This adaptive response was termed homeoviscous adaptation and has been frequently studied with a specific focus on the acyl chain composition of membrane lipids. Massspectrometry-based lipidomics can nowadays provide more comprehensive insights into the complexity of lipid remodeling during adaptive responses...... such as neurons maintain unique lipid compositions with specific physicochemical properties. To date little is known about the sensory mechanisms regulating the acyl chain profile in such specialized cells or during adaptive responses. Here we summarize our current understanding of lipid metabolic networks...

  17. Lipid droplets as ubiquitous fat storage organelles in C. elegans

    Directory of Open Access Journals (Sweden)

    Guo Fengli

    2010-12-01

    Full Text Available Abstract Background Lipid droplets are a class of eukaryotic cell organelles for storage of neutral fat such as triacylglycerol (TAG and cholesterol ester (CE. We and others have recently reported that lysosome-related organelles (LROs are not fat storage structures in the nematode C. elegans. We also reported the formation of enlarged lipid droplets in a class of peroxisomal fatty acid β-oxidation mutants. In the present study, we seek to provide further evidence on the organelle nature and biophysical properties of fat storage structures in wild-type and mutant C. elegans. Results In this study, we provide biochemical, histological and ultrastructural evidence of lipid droplets in wild-type and mutant C. elegans that lack lysosome related organelles (LROs. The formation of lipid droplets and the targeting of BODIPY fatty acid analogs to lipid droplets in live animals are not dependent on lysosomal trafficking or peroxisome dysfunction. However, the targeting of Nile Red to lipid droplets in live animals occurs only in mutants with defective peroxisomes. Nile Red labelled-lipid droplets are characterized by a fluorescence emission spectrum distinct from that of Nile Red labelled-LROs. Moreover, we show that the recently developed post-fix Nile Red staining method labels lipid droplets exclusively. Conclusions Our results demonstrate lipid droplets as ubiquitous fat storage organelles and provide a unified explanation for previous studies on fat labelling methods in C. elegans. These results have important applications to the studies of fat storage and lipid droplet regulation in the powerful genetic system, C. elegans.

  18. The effect of dietary lipid saturation and monensin-Na on the CLA ...

    African Journals Online (AJOL)

    One diet contained no ionophore antibiotic and the other monensin-Na included at 165 g/ton. These two basal diets were supplemented, according to a 2 x 3 factorial design, with three lipid sources [i.e. 20 g/kg of either beef tallow, sunflower oil or a CLA oil concentrate] differing in saturation level and fatty acid profile.

  19. Lipid metabolism in rats fed diets containing different types of lipids

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    Águila Márcia Barbosa

    2002-01-01

    Full Text Available OBJECTIVE: To assess the effect of different types of lipid diets on the lipid metabolism of aging rats. METHODS: Fifty male Wistar rats were studied from the time of weaning to 12 and 18 months of age. Their diets were supplemented as follows: with soybean oil (S, canola oil (CA, lard and egg yolk (LE, and canola oil + lard and egg yolk (CA + LE. Blood pressure (BP was measured every month, and the heart/body ratio (H/BR was determined. The rats were euthanized at the age of 12 and 18 months, and blood samples were collected for lipid analysis as follows: total cholesterol (TC, LDL-C, VLDL-C, HDL-C, triglycerides (TG, and glucose. RESULTS: The type of oil ingested by the animals significantly altered BP, H/BR, and serum lipid levels in rats at 12 and 18 months. No difference was observed in the survival curve of the animals in the different groups. The LE group had the highest BP, and the CA group was the only one in which BP did not change with aging. A reduction in the H/BR was observed in the LE and CA+LE animals. At the age of 12 months, differences in TC, HDL-C, LDL-C, VLDL-C, TG, and glucose were observed. At the age of 18 months, a significant difference in TC, HDL-C, and glucose was observed. The highest TC value was found in the CA group and the lowest in the S group. CONCLUSION: No increase in BP occurred, and an improvement was evident in the lipid profile of rats fed a diet supplemented with CA, in which an elevation in HDL-C levels was observed, as compared with levels with the other types of diet.

  20. Biologic activity of porphyromonas endodontalis complex lipids.

    Science.gov (United States)

    Mirucki, Christopher S; Abedi, Mehran; Jiang, Jin; Zhu, Qiang; Wang, Yu-Hsiung; Safavi, Kamran E; Clark, Robert B; Nichols, Frank C

    2014-09-01

    Periapical infections secondary to pulpal necrosis are associated with bacterial contamination of the pulp. Porphyromonas endodontalis, a gram-negative organism, is considered to be a pulpal pathogen. P. gingivalis is phylogenetically related to P. endodontalis and synthesizes several classes of novel complex lipids that possess biological activity, including the capacity to promote osteoclastogenesis and osteoclast activation. The purpose of this study was to extract and characterize constituent lipids of P. endodontalis and evaluate their capacity to promote proinflammatory secretory responses in the macrophage cell line, RAW 264.7, as well as their capacity to promote osteoclastogenesis and inhibit osteoblast activity. Constituent lipids of both organisms were fractionated by high-performance liquid chromatography and were structurally characterized using electrospray mass spectrometry or electrospray-mass spectrometry/mass spectrometry. The virulence potential of P. endodontalis lipids was then compared with known biologically active lipids isolated from P. gingivalis. P. endodontalis total lipids were shown to promote tumor necrosis factor alpha secretion from RAW 264.7 cells, and the serine lipid fraction appeared to account for the majority of this effect. P. endodontalis lipid preparations also increased osteoclast formation from RAW 264.7 cells, but osteoblast differentiation in culture was inhibited and appeared to be dependent on Toll-like receptor 2 expression. These effects underscore the importance of P. endodontalis lipids in promoting inflammatory and bone cell activation processes that could lead to periapical pathology. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  1. Effect of ewe's (semi-skimmed and whole) and cow's milk yogurt consumption on the lipid profile of control subjects: a crossover study.

    Science.gov (United States)

    Olmedilla-Alonso, Begoña; Nova-Rebato, Esther; García-González, Natalia; Martín-Diana, Ana-Belén; Fontecha, Javier; Delgado, David; Gredilla, Ana-Elisa; Bueno, Francisco; Asensio-Vegas, Carmen

    2017-01-01

    Yogurt is the most widely consumed fermented milk product worldwide. Studies have mainly used milk and dairy products from cow, which have a lower fat content than those from ewe and a different lipid profile. This study investigated the effect on the lipid profile of control subjects of three different set yogurts: (a) semi-skimmed ewe´s milk yogurt (2.8% milk fat); (b) whole ewe´s milk yogurt (5.8 % milk fat); (c) cow´s milk yogurt (3 % milk fat). A randomized crossover study included 30 healthy adults (16 women) to consume 250 g/yogurt/day during three consecutive 5-weeks periods separated by 4-week washouts. Blood samples were collected at the start and end of each period for the analysis of serum cholesterol (total, HDL-, LDL-) and triglycerides. We found no differences in the serum concentrations of lipid and lipoprotein fractions of the volunteers after the intake of any of the three types of yogurts. When the volunteers were grouped into two risk groups of risk according to their total cholesterol/HDL cholesterol ratio, the same differences between the groups in terms of the cholesterol (HDL-, LDL-) and triglyceride responses at baseline and after yogurt intake were found, with no effects due to the different types of yogurts. Moreover, we performed compositional analysis of the yogurts including determination of protein, fat, minerals and fatty acids (FA). Contents in protein, calcium, magnesium, non-protein nitrogen and some FA (mainly short-chain-FA) were higher for ewe's than for cow's milk yogurt. n6-n3 ratio was lower in the ewe's milk yogurt. In conclusion, yogurt intake, from ewe's and cow's milk, at levels of consumption compatible with a varied diet, neither decreases nor increases plasma lipoprotein cholesterol levels in apparently healthy individuals. As ewe's milk yogurt has a high content of macro- and micronutrients, certain target populations could benefit from its consumption.

  2. Fluorescent Lipids: Functional Parts of Fusogenic Liposomes and Tools for Cell Membrane Labeling and Visualization

    Directory of Open Access Journals (Sweden)

    Christian Kleusch

    2012-01-01

    Full Text Available In this paper a rapid and highly efficient method for controlled incorporation of fluorescent lipids into living mammalian cells is introduced. Here, the fluorescent molecules have two consecutive functions: First, they trigger rapid membrane fusion between cellular plasma membranes and the lipid bilayers of their carrier particles, so called fusogenic liposomes, and second, after insertion into cellular membranes these molecules enable fluorescence imaging of cell membranes and membrane traffic processes. We tested the fluorescent derivatives of the following essential membrane lipids for membrane fusion: Ceramide, sphingomyelin, phosphocholine, phosphatidylinositol-bisphosphate, ganglioside, cholesterol, and cholesteryl ester. Our results show that all probed lipids could more efficiently be incorporated into the plasma membrane of living cells than by using other methods. Moreover, labeling occurred in a gentle manner under classical cell culture conditions reducing cellular stress responses. Staining procedures were monitored by fluorescence microscopy and it was observed that sphingolipids and cholesterol containing free hydroxyl groups exhibit a decreased distribution velocity as well as a longer persistence in the plasma membrane compared to lipids without hydroxyl groups like phospholipids or other artificial lipid analogs. After membrane staining, the fluorescent molecules were sorted into membranes of cell organelles according to their chemical properties and biological functions without any influence of the delivery system.

  3. Clinical and Biochemical Profiles according to Homeostasis Model Assessment-insulin Resistance (HOMA-IR) in Korean Women with Polycystic Ovary Syndrome.

    Science.gov (United States)

    Lee, Da Eun; Park, Soo Yeon; Park, So Yun; Lee, Sa Ra; Chung, Hye Won; Jeong, Kyungah

    2014-12-01

    The aim of this study was to investigate the clinical and biochemical profiles according to homeostasis model assessment of insulin resistance (HOMA-IR) in Korean polycystic ovary syndrome (PCOS) patients. In 458 PCOS patients diagnosed by the Rotterdam European Society for Human Reproduction and Embryology (ESHRE) criteria, measurements of somatometry, blood test of hormones, glucose metabolic and lipid profiles, and transvaginal or transrectal ultrasonogram were carried out. HOMA-IR was then calculated and compared with the clinical and biochemical profiles related to PCOS. The patients were divided into 4 groups by quartiles of HOMA-IR. The mean level of HOMA-IR was 2.18 ± 1.73. Among the four groups separated according to HOMA-IR, body weight, body mass index (BMI), waist-to-hip ratio (WHR), triglyceride (TG), total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, lipid accumulation product (LAP) index, high-sensitivity C-reactive protein (hs-CRP), Apoprotein B, free testosterone, and sex hormone binding globulin (SHBG) were found to be significantly different. TG, LAP index, glucose metabolic profiles, and hs-CRP were positively correlated with HOMA-IR after adjustment for BMI. Our results suggest that the clinical and biochemical profiles which are applicable as cardiovascular risk factors are highly correlated with HOMA-IR in Korean women with PCOS.

  4. A REVIEW ON CORRELATION BETWEEN LIPID PROFILE AND DEPRESSION

    Directory of Open Access Journals (Sweden)

    Lalitha Devi Dhulipala

    2016-07-01

    Full Text Available Epidemiological and clinical intervention data indicate that low levels of circulating lipids and cholesterol are the risk factors for depressive symptoms. Olie et al 2011 (1 showed an association of low cholesterol and self-harm in their study. In the present scenario, depression and anxiety disorders have high prevalence rates and are frequently related. Understanding the subject and concepts/mechanisms related to neurobiological basis for these disorders is very important and the available techniques or methods are ineffective. Lipids generally play an important role in neural function in the brain. The composition of lipid of the brain influences perception, mood and behaviour. Lipids are responsible to regulate the membrane's function which acts as a barrier between the intracellular and extracellular spaces. It is found that membrane lipids determine the local behaviour and characterisation and function of proteins within the membrane. It is found from the literature that lipids can influence both exo-and endocytic processes and work within the membrane as second messengers. This paper discusses some important case studies related to the correlation between lipid profile and the depression.

  5. Bioenergetics of growth and lipid production in Chlamydomonas reinhardtii

    International Nuclear Information System (INIS)

    Küçük, Kübra; Tevatia, Rahul; Sorgüven, Esra; Demirel, Yaşar; Özilgen, Mustafa

    2015-01-01

    The study of thermodynamic aspects of the lipid, e.g., raw material for biodiesel, production in microalgae is important, as the non-lipid producing biological activities of the algal cultivation consume part of the solar energy captured during photosynthesis in expense of the exergetic efficiency of the lipid production process. The cultivation of Chlamydomonas reinhardtii (a unicellular biflagellate fresh-water microalga) is modeled as a three-step chemical mechanism representing growth, respiration, and lipid production. Further, the comprehensive thermodynamic analysis of these mechanisms is presented. The cumulative degree of perfection of the cellular proliferation, after excluding the lipid synthesis, fluctuates with no trend around 0.52 ± 0.19. The exergy analysis has indicated that C. reinhardtii prefers to maximize the lipid production when it is difficult to generate new cells. Under batch production of algal biomass, the highest heat and exergy loss per unit biomass production are accountable under the most favorable biological growth conditions, whereas the highest exergetic efficiency of the lipid production accounted under the least favorable growth conditions, which is in line with the previous studies. - Highlights: • Biomass, lipid production and respiration modeled as three-step chemical reaction. • CDP (cumulative degree of perfection) is calculated based on the model. • The CDP of the algae, after excluding the lipids, is about 0.52 ± 0.19. • Chlamydomonas reinhardtii maximized lipid production when it was difficult to grow

  6. A CROSS-SECTIONAL SURVEY ON LIPID ABNORMALITIES ASSOCIATED WITH NONDIABETIC SUBJECTS WITH CHRONIC KIDNEY DISEASE, STAGE III-V

    Directory of Open Access Journals (Sweden)

    Sibi N. S

    2017-09-01

    Full Text Available BACKGROUND Chronic kidney disease is a worldwide public health problem. The adverse outcomes of chronic kidney disease, such as kidney failure, cardiovascular disease and premature death can be prevented or delayed. Chronic renal disease is accompanied by characteristic abnormalities of lipid metabolism. High cholesterol and triglyceride plasma levels have been demonstrated to be independent risk factors for progression of renal disease in humans. The pattern of lipid abnormalities in chronic renal disease patients in Kerala, India, has not been studied. The primary aim of the study is to describe the pattern of lipid profile in nondiabetic chronic kidney disease patients. The secondary objective is to determine the proportion of patients with nondiabetic chronic kidney disease who have lipid abnormalities. MATERIALS AND METHODS Our study is a cross-sectional study conducted in Department of Internal Medicine, Government Medical College, Trivandrum, during the time period of 22-08-2014 to 22-08-2015. The study was conducted after clearance from Institutional Ethics Committee and written informed consent was obtained from all study participants. 134 nondiabetic patients who were diagnosed to have Chronic Kidney disease (CKD according to KDOQI and NKF criteria with a GFR 70 years showed significantly higher serum creatinine value and lower EGFR. Significantly, higher values of Total Cholesterol (TC, Low-Density Lipoproteins (LDL, Triglycerides (TG and Very Low-Density Lipoproteins (VLDL were seen in the age group >70 years and in stage V CKD compared to other groups. CONCLUSION Dyslipidaemia is common in nondiabetic CKD patients (67.91%. Higher stages of CKD were associated with more dyslipidaemia.

  7. Triglyceride blisters in lipid bilayers: implications for lipid droplet biogenesis and the mobile lipid signal in cancer cell membranes.

    Directory of Open Access Journals (Sweden)

    Himanshu Khandelia

    Full Text Available Triglycerides have a limited solubility, around 3%, in phosphatidylcholine lipid bilayers. Using millisecond-scale course grained molecular dynamics simulations, we show that the model lipid bilayer can accommodate a higher concentration of triolein (TO than earlier anticipated, by sequestering triolein molecules to the bilayer center in the form of a disordered, isotropic, mobile neutral lipid aggregate, at least 17 nm in diameter, which forms spontaneously, and remains stable on at least the microsecond time scale. The results give credence to the hotly debated existence of mobile neutral lipid aggregates of unknown function present in malignant cells, and to the early biogenesis of lipid droplets accommodated between the two leaflets of the endoplasmic reticulum membrane. The TO aggregates give the bilayer a blister-like appearance, and will hinder the formation of multi-lamellar phases in model, and possibly living membranes. The blisters will result in anomalous membrane probe partitioning, which should be accounted for in the interpretation of probe-related measurements.

  8. Optimization of cationic lipid mediated gene transfer: structure-function, physico-chemical, and cellular studies.

    Science.gov (United States)

    Carrière, Marie; Tranchant, Isabelle; Niore, Pierre-Antoine; Byk, Gerardo; Mignet, Nathalie; Escriou, Virginie; Scherman, Daniel; Herscovici, Jean

    2002-01-01

    The rationale design aimed at the enhancement of cationic lipid mediated gene transfer is discussed. These improvements are based on the straight evaluation of the structure-activity relationship and on the introduction of new structures. Much attention have been given to the supramolecular structures of the lipid/DNA complexes, to the effect of serum on gene transfer and to the intracellular trafficking of the lipoplexes. Finally new avenue using reducible cationic lipids has been discussed.

  9. Unraveling lipid metabolism in lipid-dependent pathogenic Malassezia yeasts

    NARCIS (Netherlands)

    Celis Ramirez, A.M.

    2017-01-01

    Malassezia yeasts are lipid-dependent fungal species that are common members of the human and animal skin microbiota. The lipid-dependency is a crucial trait in the adaptation process to grow on the skin but also plays a role in their pathogenic life style. Malassezia species can cause several skin

  10. Effect of tofacitinib on lipid levels and lipid-related parameters in patients with moderate to severe psoriasis.

    Science.gov (United States)

    Wolk, Robert; Armstrong, Ehrin J; Hansen, Peter R; Thiers, Bruce; Lan, Shuping; Tallman, Anna M; Kaur, Mandeep; Tatulych, Svitlana

    Psoriasis is a systemic inflammatory disease associated with increased cardiovascular (CV) risk and altered lipid metabolism. Tofacitinib is an oral Janus kinase inhibitor. The aim of the study was to investigate the effects of tofacitinib on traditional and nontraditional lipid parameters and CV risk markers in patients with psoriasis from a phase III study, OPT Pivotal 1. Patients with psoriasis were randomized to tofacitinib 5 or 10 mg twice daily (BID) or placebo BID. Serum samples were collected at baseline, week 4, and week 16. Analyses included serum cholesterol levels, triglycerides, lipoproteins, lipid particles, lipid-related parameters/CV risk markers, and high-density lipoprotein (HDL) function analyses. At week 16, small concurrent increases in mean low-density lipoprotein cholesterol (LDL-C) and HDL cholesterol (HDL-C) levels were observed with tofacitinib; total cholesterol/HDL-C ratio did not change. There was no significant change in the number of small dense LDL particles, which are considered to be more atherogenic than large particles, and oxidized LDL did not increase. Paraoxonase 1 activity, linked to HDL antioxidant capacity, increased, and HDL-associated serum amyloid A, which reduces the anti-atherogenic potential of HDL, decreased. HDL capacity to promote cholesterol efflux from macrophages did not change. Lecithin-cholesterol acyltransferase activity, which is associated with reverse cholesterol transport, increased. Markers of systemic inflammation, serum amyloid A and C-reactive protein, decreased with tofacitinib. While small increases in lipid levels are observed with tofacitinib treatment in patients with psoriasis, effects on selected lipid-related parameters and other circulating CV risk biomarkers are not suggestive of an increased CV risk [NCT01276639]. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.

  11. Lipid-load in peripheral blood mononuclear cells: Impact of food-consumption, dietary-macronutrients, extracellular lipid availability and demographic factors.

    Science.gov (United States)

    Ameer, Fatima; Munir, Rimsha; Usman, Hina; Rashid, Rida; Shahjahan, Muhammad; Hasnain, Shahida; Zaidi, Nousheen

    2017-04-01

    Lipid-load in peripheral blood mononuclear cells (PBMCs) has recently gained attention of the researchers working on nutritional regulation of metabolic health. Previous works have indicated that the metabolic circuitries in the circulating PBMCs are influenced by dietary-intake and macronutrient composition of diet. In the present work, we analyzed the impact of diet and dietary macronutrients on PBMCs' lipid-load. The overall analyses revealed that dietary carbohydrates and fats combinatorially induce triglyceride accumulation in PBMCs. On the other hand, dietary fats were shown to induce significant decrease in PBMCs' cholesterol-load. The effects of various demographic factors -including age, gender and body-weight- on PBMCs' lipid-load were also examined. Body-weight and age were both shown to affect PBMC's lipid-load. Our study fails to provide any direct association between extracellular lipid availability and cholesterol-load in both, freshly isolated and cultured PBMCs. The presented work significantly contributes to the current understanding of the impact of food-consumption, dietary macronutrients, extracellular lipid availability and demographic factors on lipid-load in PBMCs. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  12. Differences in Lipid Measurements by Antiretroviral Regimen Exposure in Cohorts from Asia and Australia

    Directory of Open Access Journals (Sweden)

    Amit C. Achhra

    2012-01-01

    Full Text Available We explored the mean differences in routinely measured lipids (total cholesterol, triglycerides, and high-density lipoprotein cholesterol according to exposure to different combination antiretroviral regimens in Asian (n=2051 and Australian (predominantly Caucasian, n=794 cohorts. The regimen was defined as at least 3 antiretroviral drugs with at least 2 nucleoside-reverse transcriptases (NRTIs and either of at least one protease inhibitor (PI or non-nucleoside-reverse transcriptases (NNRTIs. We categorised cART regimens as: NRTIs as tenofovir based or not; NNRTIs as nevirapine or efavirenz (but not both; and PI as atazanavir based or not. We found that the impact of various antiretroviral regimens on lipids in Asian and Australian cohorts was only different by cohort for total cholesterol (P for interaction between regimen and cohort: 0.05. The differences in total cholesterol were however small and unlikely to be of clinical significance. Overall, tenofovir with nevirapine or atazanavir was associated with the most favorable lipids, while the PI regimens without tenofovir and atazanavir were associated with least favorable lipids. We conclude that the impact of various ART regimens on lipids is largely similar in Asian and Australian cohorts and that the newer drugs such as tenofovir and atazanavir are likely to provide similar benefit in terms of lipid profiles in both populations.

  13. Lipid control and use of lipid-regulating drugs for prevention of cardiovascular events in Chinese type 2 diabetic patients: a prospective cohort study

    Directory of Open Access Journals (Sweden)

    Tong Peter CY

    2010-11-01

    Full Text Available Abstract Background Dyslipidaemia is an important but modifiable risk factor of cardiovascular disease (CVD in type 2 diabetes. Yet, the effectiveness of lipid regulating drugs in Asians is lacking. We examined the effects of lipid control and treatment with lipid regulating drugs on new onset of CVD in Chinese type 2 diabetic patients. Methods In this prospective cohort consisting of 4521 type 2 diabetic patients without history of CVD and naïve for lipid regulating treatment recruited consecutively from 1996 to 2005, 371 developed CVD after a median follow-up of 4.9 years. We used Cox proportional hazard regression to obtain the hazard ratios (HR of lipids and use of lipid regulating drugs for risk of CVD. Results The multivariate-adjusted HR (95% confidence interval of CVD in patients with high LDL-cholesterol (≥ 3.0 mmol/L was 1.36 (1.08 - 1.71, compared with lower values. Using the whole range value of HDL-cholesterol, the risk of CVD was reduced by 41% with every 1 mmol/L increase in HDL-cholesterol. Plasma triglyceride did not predict CVD. Statins use was associated with lower CVD risk [HR = 0.66 (0.50 - 0.88]. In sub-cohort analysis, statins use was associated with a HR of 0.60 (0.44 - 0.82 in patients with high LDL-cholesterol (≥ 3.0 mmol/L and 0.49 (0.28 - 0.88 in patients with low HDL-cholesterol. In patients with LDL-cholesterol Conclusions In Chinese type 2 diabetic patients, high LDL-cholesterol and low HDL-cholesterol predicted incident CVD. Overall, patients treated with statins had 40-50% risk reduction in CVD compared to non-users.

  14. The effects of therapeutic concentrations ofamisulpride andrisperidone on human plasma lipid peroxidation – invitro studies

    Directory of Open Access Journals (Sweden)

    Anna Dietrich-Muszalska

    2011-09-01

    Full Text Available Introduction: Antipsychotics may in different ways affect the oxidative stress measured by plasma lipid peroxidation. Probably some of them may intensify the oxidative balance disturbances occurring in schizophrenia. The effects of amisulpride and risperidone on redox processes are not known sufficiently yet. Aim of the study: Establishment of the effects of amisulpride and risperidone on human plasma lipid peroxidation measured by determination of the level of thiobarbituric acid-reactive substances (TBARS, in vitro. Material and methods: Blood for the studies was collected from healthy volunteers (aged 24-26 years for ACD solution. Active substances of the examined drugs were dissolved in 0.01% dimethylsulfoxide (DMSO to the final concentrations (of amisulpride 578 ng/ml and risperidone 64 ng/ml and incubated with plasma for 1 and 24 hours at 37ºC. For each experiment the control samples of plasma with DMSO (without the drug were performed. The lipid peroxidation level was measured in plasma by determining the TBARS concentration, using the spectrophotometric method (acc. to Rice-Evans, 1991. The results were analysed using the following statistical methods: the paired Student t-test and ANOVA II variance analysis and NIR test (StatSoft Inc., Statistica v. 6.0. Results: The ANOVA II variance analysis indicated significant differences in the effects of both drugs on TBARS level (F=4.26; df=2, p0.05. Conclusion: Amisulpride and risperidone in concentrations corresponding to doses recommended for treatment of acute episode of schizophrenia do not induce oxidative stress measured by lipid peroxidation. Unlike risperidone, amisulpride exhibits antioxidative effects.

  15. Application of Proteomics and Lipid Studies in Environmental Biotechnology

    Energy Technology Data Exchange (ETDEWEB)

    Mukhopadhyay, Aindrila

    2008-08-12

    The overview of changes in protein levels or states in response to a growth condition, stress, mutation or metabolic engineering is invaluable in understanding the physiology of a microbial system. The lipid profile of the cell is similarly a valuable diagnostic of the cellular response and health, especially in context of survival in a fluctuating environment. To obtain comprehensive cellular models, post-transcriptional cell wide surveys at the levels of proteins and lipids are required. Both these fields have been greatly bolstered by the development of high throughput methods using mass spectrometry. Multiple strategies now exist for the identification of proteins, and numerous workflows to quantify protein abundance have also been developed. Cellular profiling such as these allows us to assess the potential of a microbial system for environmental applications such as bioremediation and bio-energy.

  16. Selective Interaction of a Cationic Polyfluorene with Model Lipid Membranes: Anionic versus Zwitterionic Lipids

    Directory of Open Access Journals (Sweden)

    Zehra Kahveci

    2014-03-01

    Full Text Available This paper explores the interaction mechanism between the conjugated polyelectrolyte {[9,9-bis(6'-N,N,N-trimethylammoniumhexyl]fluorene-phenylene}bromide (HTMA-PFP and model lipid membranes. The study was carried out using different biophysical techniques, mainly fluorescence spectroscopy and microscopy. Results show that despite the preferential interaction of HTMA-PFP with anionic lipids, HTMA-PFP shows affinity for zwitterionic lipids; although the interaction mechanism is different as well as HTMA-PFP’s final membrane location. Whilst the polyelectrolyte is embedded within the lipid bilayer in the anionic membrane, it remains close to the surface, forming aggregates that are sensitive to the physical state of the lipid bilayer in the zwitterionic system. The different interaction mechanism is reflected in the polyelectrolyte fluorescence spectrum, since the maximum shifts to longer wavelengths in the zwitterionic system. The intrinsic fluorescence of HTMA-PFP was used to visualize the interaction between polymer and vesicles via fluorescence microscopy, thanks to its high quantum yield and photostability. This technique allows the selectivity of the polyelectrolyte and higher affinity for anionic membranes to be observed. The results confirmed the appropriateness of using HTMA-PFP as a membrane fluorescent marker and suggest that, given its different behaviour towards anionic and zwitterionic membranes, HTMA-PFP could be used for selective recognition and imaging of bacteria over mammalian cells.

  17. Lipid dip-pen nanolithography on self-assembled monolayers

    International Nuclear Information System (INIS)

    Gavutis, Martynas; Navikas, Vytautas; Rakickas, Tomas; Vaitekonis, Šarūnas; Valiokas, Ramūnas

    2016-01-01

    Dip-pen nanolithography (DPN) with lipids as an ink enables functional micro/nanopatterning on different substrates at high process speeds. However, only a few studies have addressed the influence of the physicochemical properties of the surface on the structure and phase behavior of DPN-printed lipid assemblies. Therefore, by combining the scanning probe and optical imaging techniques in this work we have analyzed lipid microdomain formation on the self-assembled monolayers (SAMs) on gold as well-defined model surfaces that displayed hydrophilic (protein-repellent) or hydrophobic (protein-adhesive) characteristics. We have found that on the tri(ethylene glycol)-terminated SAM the lipid ink transfer was fast (∼10 –1 μm 3 s −1 ), quasi-linear and it yielded unstable, sparsely packed lipid microspots. Contrary to this, on the methyl-terminated SAM the lipid transfer was ∼20 times slower, nonlinear, and the obtained stable dots of ∼1 μm in diameter consisted of lipid multilayers. Our comparative analysis indicated that the measured lipid transfer was consistent with the previously reported so-called polymer transfer model (Felts et al 2012, Nanotechnology 23 215301). Further on, by employing the observed distinct contrast in the DPN ink behavior we constructed confined lipid microdomains on pre-patterned SAMs, in which the lipids assembled either into monolayer or multilamellar phases. Such microdomains can be further utilized for lipid membrane mimetics in microarray and lab-on-a-chip device formats. (paper)

  18. LIPID SYNTHESIS, INTRACELLULAR TRANSPORT, AND SECRETION

    Science.gov (United States)

    Stein, Olga; Stein, Yechezkiel

    1967-01-01

    In the mammary glands of lactating albino mice injected intravenously with 9, 10-oleic acid-3H or 9, 10-palmitic acid-3H, it has been shown that the labeled fatty acids are incorporated into mammary gland glycerides. The labeled lipid in the mammary gland 1 min after injection was in esterified form (> 95%), and the radioautographic reaction was seen over the rough endoplasmic reticulum and over lipid droplets, both intracellular and intraluminal. At 10–60 min after injection, the silver grains were concentrated predominantly over lipid droplets. There was no concentration of radioactivity over the granules in the Golgi apparatus, at any time interval studied. These findings were interpreted to indicate that after esterification of the fatty acid into glycerides in the rough endoplasmic reticulum an in situ aggregation of lipid occurs, with acquisition of droplet form. The release of the lipid into the lumen proceeds directly and not through the Golgi apparatus, in contradistinction to the mode of secretion of casein in the mammary gland or of lipoprotein in the liver. The presence of strands of endoplasmic reticulum attached to intraluminal lipid droplets provides a structural counterpart to the milk microsomes described in ruminant milk. PMID:6033535

  19. Analysis of Lipoplex Structure and Lipid Phase Changes

    Energy Technology Data Exchange (ETDEWEB)

    Koynova, Rumiana

    2012-07-18

    Efficient delivery of genetic material to cells is needed for tasks of utmost importance in the laboratory and clinic, such as gene transfection and gene silencing. Synthetic cationic lipids can be used as delivery vehicles for nucleic acids and are now considered the most promising nonviral gene carriers. They form complexes (lipoplexes) with the polyanionic nucleic acids. A critical obstacle for clinical application of the lipid-mediated DNA delivery (lipofection) is its unsatisfactory efficiency for many cell types. Understanding the mechanism of lipid-mediated DNA delivery is essential for their successful application, as well as for a rational design and synthesis of novel cationic lipoid compounds for enhanced gene delivery. A viewpoint now emerging is that the critical factor in lipid-mediated transfection is the structural evolution of lipoplexes within the cell, upon interacting and mixing with cellular lipids. In particular, recent studies showed that the phase evolution of lipoplex lipids upon interaction and mixing with membrane lipids appears to be decisive for transfection success: specifically, lamellar lipoplex formulations, which were readily susceptible to undergoing lamellar-nonlamellar phase transition upon mixing with cellular lipids and were found rather consistently associated with superior transfection potency, presumably as a result of facilitated DNA release. Thus, understanding the lipoplex structure and the phase changes upon interacting with membrane lipids is important for the successful application of the cationic lipids as gene carriers.

  20. Protein-induced bilayer Perturbations: Lipid ordering and hydrophobic coupling

    DEFF Research Database (Denmark)

    Petersen, Frederic Nicolas Rønne; Laursen, Ib; Bohr, Henrik

    2009-01-01

    The host lipid bilayer is increasingly being recognized as an important non-specific regulator of membrane protein function. Despite considerable progress the interplay between hydrophobic coupling and lipid ordering is still elusive. We use electron spin resonance (ESR) to study the interaction...... between the model protein gramicidin and lipid bilayers of varying thickness. The free energy of the interaction is up to −6 kJ/mol; thus not strongly favored over lipid–lipid interactions. Incorporation of gramicidin results in increased order parameters with increased protein concentration...... and hydrophobic mismatch. Our findings also show that at high protein:lipid ratios the lipids are motionally restricted but not completely immobilized. Both exchange on and off rate values for the lipid ↔ gramicidin interaction are lowest at optimal hydrophobic matching. Hydrophobic mismatch of few Å results...

  1. Update of the LIPID MAPS comprehensive classification system for lipids

    NARCIS (Netherlands)

    Fahy, E.; Subramaniam, S.; Murphy, R.C.; Nishijima, M.; Raetz, C.R.H.; Shimizu, T.; Spener, F.; van Meer, G.|info:eu-repo/dai/nl/068570368; Wakelam, M.J.O.; Dennis, E.A.

    2009-01-01

    In 2005, the International Lipid Classification and Nomenclature Committee under the sponsorship of the LIPID MAPS Consortium developed and established a “Comprehensive Classification System for Lipids” based on well-defined chemical and biochemical principles and using an ontology that is

  2. Study on the relationship between the levels of serum cholylglycine (CG) and blood lipids in pregnant women

    International Nuclear Information System (INIS)

    You Jianfei; Lv Shiming; Wang Qiong; Zhu Yuning

    2005-01-01

    Objective: To investigate the prevalence of intrahepatic cholestasis during pregnancy and the relationship between levels of serum CG and blood lipids. Methods: Serum CG, blood lipid and liver function profile were examined in 2040 women with pregnancy during the second or third trimester. Among these pregnant women, 57 were diagnosed as with intrahepatic cholestasis. Blood lipids (TG, cholesterol, HDL, LDL) and ALP levels in 50 of the 57 pregnant women were studied and compared with those in 50 otherwise normal pregnant women as controls. Results: Serum CG levels were above normal range in 372 of the 2040 pregnant women (18.5%). Fifty seven of these 372 pregnant women were confirmed to be with intrahepatic cholestasis (2.8% of the 2040 pregnancies). The TG, cholesterol, LDL contents and ALP levels in the pregnant women with intrahepatic cholestasis were significantly higher (P 0.05) than those in controls. Conclusion: Intrahepatic cholestasis developed in a substantial proportion of pregnant women (2.8% in this study) and should be carefully monitored due to possible damage to the fetus. Serum CG was shown to be an early and sensitive marker for the diagnosis of intrahepatic cholestasis. Changes of blood lipid and ALP levels were related to disease status. (authors)

  3. Extraction and classification of lipids from seeds of persea ...

    African Journals Online (AJOL)

    Seed lipids of Persea americana and Chrysophyllum albidum were studied. Lipids were extracted with chloroform-methanol, analysed with silicic column chromatography and thin layer chromatography. The total lipid content of Persea americana was 10.8% while that of Chrysophyllum albidum was 7.7%. Fractionation of ...

  4. Selective upregulation of lipid metabolism in skeletal muscle of foraging juvenile king penguins: an integrative study.

    Science.gov (United States)

    Teulier, Loic; Dégletagne, Cyril; Rey, Benjamin; Tornos, Jérémy; Keime, Céline; de Dinechin, Marc; Raccurt, Mireille; Rouanet, Jean-Louis; Roussel, Damien; Duchamp, Claude

    2012-06-22

    The passage from shore to marine life of juvenile penguins represents a major energetic challenge to fuel intense and prolonged demands for thermoregulation and locomotion. Some functional changes developed at this crucial step were investigated by comparing pre-fledging king penguins with sea-acclimatized (SA) juveniles (Aptenodytes patagonicus). Transcriptomic analysis of pectoralis muscle biopsies revealed that most genes encoding proteins involved in lipid transport or catabolism were upregulated, while genes involved in carbohydrate metabolism were mostly downregulated in SA birds. Determination of muscle enzymatic activities showed no changes in enzymes involved in the glycolytic pathway, but increased 3-hydroxyacyl-CoA dehydrogenase, an enzyme of the β-oxidation pathway. The respiratory rates of isolated muscle mitochondria were much higher with a substrate arising from lipid metabolism (palmitoyl-L-carnitine) in SA juveniles than in terrestrial controls, while no difference emerged with a substrate arising from carbohydrate metabolism (pyruvate). In vivo, perfusion of a lipid emulsion induced a fourfold larger thermogenic effect in SA than in control juveniles. The present integrative study shows that fuel selection towards lipid oxidation characterizes penguin acclimatization to marine life. Such acclimatization may involve thyroid hormones through their nuclear beta receptor and nuclear coactivators.

  5. Lipid Raft, Regulator of Plasmodesmal Callose Homeostasis

    Directory of Open Access Journals (Sweden)

    Arya Bagus Boedi Iswanto

    2017-04-01

    Full Text Available Abstract: The specialized plasma membrane microdomains known as lipid rafts are enriched by sterols and sphingolipids. Lipid rafts facilitate cellular signal transduction by controlling the assembly of signaling molecules and membrane protein trafficking. Another specialized compartment of plant cells, the plasmodesmata (PD, which regulates the symplasmic intercellular movement of certain molecules between adjacent cells, also contains a phospholipid bilayer membrane. The dynamic permeability of plasmodesmata (PDs is highly controlled by plasmodesmata callose (PDC, which is synthesized by callose synthases (CalS and degraded by β-1,3-glucanases (BGs. In recent studies, remarkable observations regarding the correlation between lipid raft formation and symplasmic intracellular trafficking have been reported, and the PDC has been suggested to be the regulator of the size exclusion limit of PDs. It has been suggested that the alteration of lipid raft substances impairs PDC homeostasis, subsequently affecting PD functions. In this review, we discuss the substantial role of membrane lipid rafts in PDC homeostasis and provide avenues for understanding the fundamental behavior of the lipid raft–processed PDC.

  6. Lipid Raft, Regulator of Plasmodesmal Callose Homeostasis.

    Science.gov (United States)

    Iswanto, Arya Bagus Boedi; Kim, Jae-Yean

    2017-04-03

    A bstract: The specialized plasma membrane microdomains known as lipid rafts are enriched by sterols and sphingolipids. Lipid rafts facilitate cellular signal transduction by controlling the assembly of signaling molecules and membrane protein trafficking. Another specialized compartment of plant cells, the plasmodesmata (PD), which regulates the symplasmic intercellular movement of certain molecules between adjacent cells, also contains a phospholipid bilayer membrane. The dynamic permeability of plasmodesmata (PDs) is highly controlled by plasmodesmata callose (PDC), which is synthesized by callose synthases (CalS) and degraded by β-1,3-glucanases (BGs). In recent studies, remarkable observations regarding the correlation between lipid raft formation and symplasmic intracellular trafficking have been reported, and the PDC has been suggested to be the regulator of the size exclusion limit of PDs. It has been suggested that the alteration of lipid raft substances impairs PDC homeostasis, subsequently affecting PD functions. In this review, we discuss the substantial role of membrane lipid rafts in PDC homeostasis and provide avenues for understanding the fundamental behavior of the lipid raft-processed PDC.

  7. Lipid transport and human brain development.

    Science.gov (United States)

    Betsholtz, Christer

    2015-07-01

    How the human brain rapidly builds up its lipid content during brain growth and maintains its lipids in adulthood has remained elusive. Two new studies show that inactivating mutations in MFSD2A, known to be expressed specifically at the blood-brain barrier, lead to microcephaly, thereby offering a simple and surprising solution to an old enigma.

  8. Lipid stability in meat and meat products.

    Science.gov (United States)

    Morrissey, P A; Sheehy, P J; Galvin, K; Kerry, J P; Buckley, D J

    1998-01-01

    Lipid oxidation is one of the main factors limiting the quality and acceptability of meats and meat products. Oxidative damage to lipids occurs in the living animal because of an imbalance between the production of reactive oxygen species and the animal's defence mechanisms. This may be brought about by a high intake of oxidized lipids or poly-unsaturated fatty acids, or a low intake of nutrients involved in the antioxidant defence system. Damage to lipids may be accentuated in the immediate post-slaughter period and, in particular, during handling, processing, storage and cooking. In recent years, pressure to reduce artificial additive use in foods has led to attempts to increase meat stability by dietary strategies. These include supplementation of animal diets with vitamin E, ascorbic acid, or carotenoids, or withdrawal of trace mineral supplements. Dietary vitamin E supplementation reduces lipid and myoglobin oxidation, and, in certain situations, drip losses in meats. However, vitamin C supplementation appears to have little, if any, beneficial effects on meat stability. The effect of feeding higher levels of carotenoids on meat stability requires further study. Some studies have demonstrated that reducing the iron and copper content of feeds improves meat stability. Post-slaughter carnosine addition may be an effective means of improving lipid stability in processed meats, perhaps in combination with dietary vitamin E supplementation.

  9. Understanding carbon nanotube channel formation in the lipid membrane

    Science.gov (United States)

    Choi, Moon-ki; Kim, Hyunki; Lee, Byung Ho; Kim, Teayeop; Rho, Junsuk; Kim, Moon Ki; Kim, Kyunghoon

    2018-03-01

    Carbon nanotubes (CNTs) have been considered a prominent nano-channel in cell membranes because of their prominent ion-conductance and ion-selectivity, offering agents for a biomimetic channel platform. Using a coarse-grained molecular dynamics simulation, we clarify a construction mechanism of vertical CNT nano-channels in a lipid membrane for a long period, which has been difficult to observe in previous CNT-lipid interaction simulations. The result shows that both the lipid coating density and length of CNT affect the suitable fabrication condition for a vertical and stable CNT channel. Also, simulation elucidated that a lipid coating on the surface of the CNT prevents the CNT from burrowing into the lipid membrane and the vertical channel is stabilized by the repulsion force between the lipids in the coating and membrane. Our study provides an essential understanding of how CNTs can form stable and vertical channels in the membrane, which is important for designing new types of artificial channels as biosensors for bio-fluidic studies.

  10. Acyl-Lipid Metabolism

    Science.gov (United States)

    Li-Beisson, Yonghua; Shorrosh, Basil; Beisson, Fred; Andersson, Mats X.; Arondel, Vincent; Bates, Philip D.; Baud, Sébastien; Bird, David; DeBono, Allan; Durrett, Timothy P.; Franke, Rochus B.; Graham, Ian A.; Katayama, Kenta; Kelly, Amélie A.; Larson, Tony; Markham, Jonathan E.; Miquel, Martine; Molina, Isabel; Nishida, Ikuo; Rowland, Owen; Samuels, Lacey; Schmid, Katherine M.; Wada, Hajime; Welti, Ruth; Xu, Changcheng; Zallot, Rémi; Ohlrogge, John

    2013-01-01

    Acyl lipids in Arabidopsis and all other plants have a myriad of diverse functions. These include providing the core diffusion barrier of the membranes that separates cells and subcellular organelles. This function alone involves more than 10 membrane lipid classes, including the phospholipids, galactolipids, and sphingolipids, and within each class the variations in acyl chain composition expand the number of structures to several hundred possible molecular species. Acyl lipids in the form of triacylglycerol account for 35% of the weight of Arabidopsis seeds and represent their major form of carbon and energy storage. A layer of cutin and cuticular waxes that restricts the loss of water and provides protection from invasions by pathogens and other stresses covers the entire aerial surface of Arabidopsis. Similar functions are provided by suberin and its associated waxes that are localized in roots, seed coats, and abscission zones and are produced in response to wounding. This chapter focuses on the metabolic pathways that are associated with the biosynthesis and degradation of the acyl lipids mentioned above. These pathways, enzymes, and genes are also presented in detail in an associated website (ARALIP: http://aralip.plantbiology.msu.edu/). Protocols and methods used for analysis of Arabidopsis lipids are provided. Finally, a detailed summary of the composition of Arabidopsis lipids is provided in three figures and 15 tables. PMID:23505340

  11. Oxidized lipids enhance RANKL production by T lymphocytes: implications for lipid-induced bone loss.

    Science.gov (United States)

    Graham, Lucia S; Parhami, Farhad; Tintut, Yin; Kitchen, Christina M R; Demer, Linda L; Effros, Rita B

    2009-11-01

    Osteoporosis is a systemic disease that is associated with increased morbidity, mortality and health care costs. Whereas osteoclasts and osteoblasts are the main regulators of bone homeostasis, recent studies underscore a key role for the immune system, particularly via activation-induced T lymphocyte production of receptor activator of NFkappaB ligand (RANKL). Well-documented as a mediator of T lymphocyte/dendritic cell interactions, RANKL also stimulates the maturation and activation of bone-resorbing osteoclasts. Given that lipid oxidation products mediate inflammatory and metabolic disorders such as osteoporosis and atherosclerosis, and since oxidized lipids affect several T lymphocyte functions, we hypothesized that RANKL production might also be subject to modulation by oxidized lipids. Here, we show that short term exposure of both unstimulated and activated human T lymphocytes to minimally oxidized low density lipoprotein (LDL), but not native LDL, significantly enhances RANKL production and promotes expression of the lectin-like oxidized LDL receptor-1 (LOX-1). The effect, which is also observed with 8-iso-Prostaglandin E2, an inflammatory isoprostane produced by lipid peroxidation, is mediated via the NFkappaB pathway, and involves increased RANKL mRNA expression. The link between oxidized lipids and T lymphocytes is further reinforced by analysis of hyperlipidemic mice, in which bone loss is associated with increased RANKL mRNA in T lymphocytes and elevated RANKL serum levels. Our results suggest a novel pathway by which T lymphocytes contribute to bone changes, namely, via oxidized lipid enhancement of RANKL production. These findings may help elucidate clinical associations between cardiovascular disease and decreased bone mass, and may also lead to new immune-based approaches to osteoporosis.

  12. A lipid E-MAP identifies Ubx2 as a critical regulator of lipid saturation and lipid bilayer stress

    DEFF Research Database (Denmark)

    Surma, Michal A; Klose, Christian; Peng, Debby

    2013-01-01

    Biological membranes are complex, and the mechanisms underlying their homeostasis are incompletely understood. Here, we present a quantitative genetic interaction map (E-MAP) focused on various aspects of lipid biology, including lipid metabolism, sorting, and trafficking. This E-MAP contains ∼250......,000 negative and positive genetic interaction scores and identifies a molecular crosstalk of protein quality control pathways with lipid bilayer homeostasis. Ubx2p, a component of the endoplasmic-reticulum-associated degradation pathway, surfaces as a key upstream regulator of the essential fatty acid (FA...

  13. Cardiac lipid accumulation associated with diastolic dysfunction in obese mice

    DEFF Research Database (Denmark)

    Christoffersen, Christina; Bollano, Entela; Lindegaard, Marie L S

    2003-01-01

    Obesity may confer cardiac dysfunction due to lipid accumulation in cardiomyocytes. To test this idea, we examined whether obese ob/ob mice display heart lipid accumulation and cardiac dysfunction. Ob/ob mouse hearts had increased expression of genes mediating extracellular generation, transport....../ob mice and 2.5 +/- 0.1 in ob/+ mice (P = 0.0001). In contrast, the indexes of systolic function and heart brain natriuretic peptide mRNA expression were only marginally affected and unaffected, respectively, in ob/ob compared with ob/+ mice. The results suggest that ob/ob mouse hearts have increased...... across the myocyte cell membrane, intracellular transport, mitochondrial uptake, and beta-oxidation of fatty acids compared with ob/+ mice. Accordingly, ob/ob mouse hearts contained more triglyceride (6.8 +/- 0.4 vs. 2.3 +/- 0.4 microg/mg; P hearts. Histological examinations...

  14. Antioxidant effect of bisphosphonates and simvastatin on chondrocyte lipid peroxidation

    International Nuclear Information System (INIS)

    Dombrecht, E.J.; De Tollenaere, C.B.; Aerts, K.; Cos, P.; Schuerwegh, A.J.; Bridts, C.H.; Van Offel, J.F.; Ebo, D.G.; Stevens, W.J.; De Clerck, L.S.

    2006-01-01

    The objective of this study was to evaluate the effect of bisphosphonates (BPs) and simvastatin on chondrocyte lipid peroxidation. For this purpose, a flow cytometrical method using C11-BODIPY 581/591 was developed to detect hydroperoxide-induced lipid peroxidation in chondrocytes. Tertiary butylhydroperoxide (t-BHP) induced a time and concentration dependent increase in chondrocyte lipid peroxidation. Addition of a Fe 2+ /EDTA complex to t-BHP or hydrogen peroxide (H 2 O 2 ) clearly enhanced lipid peroxidation. The lipophilic simvastatin demonstrated a small inhibition in the chondrocyte lipid peroxidation. None of three tested BPs (clodronate, pamidronate, and risedronate) had an effect on chondrocyte lipid peroxidation induced by t-BHP. However, when Fe 2+ /EDTA complex was added to t-BHP or H 2 O 2 , BPs inhibited the lipid peroxidation process varying from 25% to 58%. This study demonstrates that BPs have antioxidant properties as iron chelators, thereby inhibiting the chondrocyte lipid peroxidation. These findings add evidence to the therapeutic potential of bisphosphonates and statins in rheumatoid arthritis

  15. Interaction of polycationic antibiotics with Pseudomonas aeruginosa lipopolysaccharide and lipid A studied by using dansyl-polymyxin.

    Science.gov (United States)

    Moore, R A; Bates, N C; Hancock, R E

    1986-01-01

    A fluorescent derivative of polymyxin B (dansyl-polymyxin) was used to study the interaction of polycations with lipopolysaccharide (LPS) and lipid A from Pseudomonas aeruginosa. Dansyl-polymyxin became bound to LPS and lipid A sites, including Mg2+-binding sites, resulting in a 20-fold enhancement of fluorescence. A Hill plot of the binding data showed that the binding of dansyl-polymyxin to LPS was cooperative (n = 1.98) and of high affinity (S0.5 = 0.38 microM). The maximal binding capacity of LPS was approximately four molecules of dansyl-polymyxin per mol of LPS. The dansyl-polymyxin interaction with lipid A displayed similar kinetics (n = 2.26; S0.5 = 0.38 microM), and the maximal binding capacity was approximately 2 mol of dansyl-polymyxin per mol of lipid A. A variety of polycationic compounds, including gentamicin, streptomycin, and polymyxin B, as well as Mg2+, were able to displace dansyl-polymyxin bound to LPS or to lipid A. Marked differences both in terms of the degree of displacement and in terms of the amount of competing polycation required to displace a given amount of dansyl-polymyxin were observed. Addition of excess polymyxin B resulted in displacement of all of the dansyl-polymyxin, demonstrating that only polymyxin-binding sites were being probed. Our data demonstrate that polymyxin B binds to multiple sites on LPS, including sites which bind aminoglycoside antibiotics and other polycationic compounds. PMID:3013085

  16. Effects of blood glucose, blood lipids and blood pressure control on recovery of patients with gastric cancer complicated with metabolic syndrome after radical gastrectomy.

    Science.gov (United States)

    Sun, Li; Zhou, Pingping; Hua, Qingli; Jin, Changming; Guo, Chunling; Song, Bing

    2018-06-01

    This study aimed to investigate the effects of blood glucose, blood lipids and blood pressure control on recovery of patients with gastric cancer complicated with metabolic syndrome (MS) after radical gastrectomy. A total of 150 patients with gastric cancer, who were treated in Daqing Longnan Hospital from November, 2015 to May, 2017, were enrolled in this study. The patients were divided into the MS group (80 cases) and non-MS group (70 cases). Patients in the MS group were given corresponding drugs to control blood pressure, blood lipids and blood glucose, while patients in the non-MS group were not treated with those drugs. Patients in the MS group were divided into the normal and abnormal groups according to the levels of blood glucose, blood lipids and blood pressure. Moreover, occurrences of complications were compared between the normal and abnormal groups. Before surgery, blood glucose, blood lipids and blood pressure in the MS group were significantly higher than those in the non-MS group (pblood glucose, blood lipids and blood pressure of the MS group decreased significantly compared to those before operation (pblood glucose, 2 h postprandial blood glucose, glycosylated hemoglobin, total triglycerides (TGs), LDL, mean blood pressure and BMI (pblood glucose, blood lipids and blood pressure in patients with gastric cancer complicated with MS after radical gastrectomy can reduce the incidence of postoperative complications and promote postoperative recovery.

  17. Diffusion studies on permeable nitroxyl spin probes through bilayer lipid membranes: A low frequency ESR study

    International Nuclear Information System (INIS)

    Meenakumari, V.; Benial, A. Milton Franklin; Utsumi, Hideo; Ichikawa, Kazuhiro; Yamada, Ken-ichi; Hyodo, Fuminori; Jawahar, A.

    2015-01-01

    Electron spin resonance (ESR) studies were carried out for permeable 2mM 14 N-labeled deutrated 3 Methoxy carbonyl-2,2,5,5-tetramethyl-pyrrolidine-1-oxyl (MC-PROXYL) in pure water and 1mM, 2mM, 3mM, 4mM concentration of 14N-labeled deutrated MC-PROXYL in 400mM concentration of liposomal solution by using a 300 MHz ESR spectrometer. The ESR parameters such as linewidth, hyperfine coupling constant, g-factor, partition parameter and permeability were reported for these samples. The line broadening was observed for the nitroxyl spin probe in the liposomal solution. The line broadening indicates that the high viscous nature of the liposomal solution. The partition parameter and permeability values indicate the maximum diffusion of nitroxyl spin probes in the bilayer lipid membranes at 2 mM concentration of nitroxyl radical. This study illustrates that ESR can be used to differentiate between the intra and extra- membrane water by loading the liposome vesicles with a lipid-permeable nitroxyl spin probe. From the ESR results, the spin probe concentration was optimized as 2mM in liposomal solution for ESR phantom studies/imaging, invivo and invitro experiments

  18. Comparative Proteome Analysis between High Lipid-Producing Strain Mucor circinelloides WJ11 and Low Lipid-Producing Strain CBS 277.49.

    Science.gov (United States)

    Tang, Xin; Chen, Haiqin; Gu, Zhennan; Zhang, Hao; Chen, Yong Q; Song, Yuanda; Chen, Wei

    2017-06-21

    Mucor circinelloides is one of few oleaginous fungi that produces a useful oil rich in γ-linolenic acid, but it usually only produces <25% total lipid. Nevertheless, we isolated a new strain WJ11 that can produce up to 36% lipid of cell dry weight. In this study, we have systematically analyzed the global changes in protein levels between the high lipid-producing strain WJ11 and the low lipid-producing strain CBS 277.49 (15%, lipid/cell dry weight) at lipid accumulation phase through comparative proteome analysis. Proteome analysis demonstrated that the branched-chain amino acid and lysine metabolism, glycolytic pathway, and pentose phosphate pathway in WJ11 were up-regulated, while the activities of tricarboxylic acid cycle and branch point enzyme for synthesis of isoprenoids were retarded compared with CBS 277.49. The coordinated regulation at proteome level indicate that more acetyl-CoA and NADPH are provided for fatty acid biosynthesis in WJ11 compared with CBS 277.49.

  19. Causes of failure to achieve the low density lipoprotein cholesterol therapeutic target in patients with high and very high vascular risk controlled in Lipid and Vascular Risk Units. EROMOT study.

    Science.gov (United States)

    Morales, Clotilde; Plana, Núria; Arnau, Anna; Matas, Laia; Mauri, Marta; Vila, Àlex; Vila, Lluís; Soler, Cristina; Montesinos, Jesús; Masana, Lluís; Pedro-Botet, Juan

    Determination of the level of achievement of the low density lipoprotein cholesterol (LDL-C) therapeutic target in patients with high and very high vascular risk treated in Lipid Units, as well as the causes of non-achievement. Multicentre retrospective observational study that included patients over 18 years with high and very high vascular risk, according to the criteria of the 2012 European Guidelines on Cardiovascular Disease Prevention, referred consecutively to Lipid Units between January and June 2012 and with follow-up two years after the first visit. The study included a total of 243 patients from 16 lipid units. The mean age was 52.2 years (SD 13.7), of whom 62.6% were males, and 40.3% of them were very high risk. At the first visit, 86.8% (25.1% in combination) and 95.0% (47.3% in combination) in the second visit (P<.001) were treated with lipid-lowering treatment. The therapeutic target was achieved by 28% (95 CI: 22.4-34.1). As regards the causes of non-achievement, 24.6% were related to the medication (10.3% maximum tolerated dose and 10.9% due to the appearance of adverse effects), 43.4% due to the physician (19.4% by inertia, 13.7% considering that target already reached), and 46.9% due to the patient, highlighting the therapeutic non-compliance (31,4%). LDL-C targets were achieved in about one-third of patients. The low adherence of the patient, followed by medical inertia are the most frequent causes that can explain these results. Copyright © 2017 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Silicon supported lipid-DNA thin film structures at varying temperature studied by energy dispersive X-ray diffraction and neutron reflectivity.

    Science.gov (United States)

    Domenici, F; Castellano, C; Dell'Unto, F; Albinati, A; Congiu, A

    2011-11-01

    Non-viral gene transfection by means of lipid-based nanosystems, such as solid supported lipid assemblies, is often limited due to their lack of stability and the consequent loss of efficiency. Therefore not only a detailed thermo-lyotropic study of these DNA-lipid complexes is necessary to understand their interaction mechanisms, but it can also be considered as a first step in conceiving and developing new transfection biosystems. The aim of our study is a structural characterization of 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC)-dimethyl-dioctadecyl-ammonium bromide (DDAB)-DNA complex at varying temperature using the energy dispersive X-ray diffraction (EDXD) and neutron reflectivity (NR) techniques. We have shown the formation of a novel thermo-lyotropic structure of DOPC/DDAB thin film self-organized in multi-lamellar planes on (100)-oriented silicon support by spin coating, thus enlightening its ability to include DNA strands. Our NR measurements indicate that the DOPC/DDAB/DNA complex forms temperature-dependent structures. At 65°C and relative humidity of 100% DNA fragments are buried between single lamellar leaflets constituting the hydrocarbon core of the lipid bilayers. This finding supports the consistency of the hydrophobic interaction model, which implies that the coupling between lipid tails and hypo-hydrated DNA single strands could be the driving force of DNA-lipid complexation. Upon cooling to 25°C, EDXD analysis points out that full-hydrated DOPC-DDAB-DNA can switch in a different metastable complex supposed to be driven by lipid heads-DNA electrostatic interaction. Thermotropic response analysis also clarifies that DOPC has a pivotal role in promoting the formation of our observed thermophylic silicon supported lipids-DNA assembly. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. The interaction of M13 coat protein with lipid bilayers : a spectroscopic study

    NARCIS (Netherlands)

    Sanders, J.C.

    1992-01-01

    In this thesis a small part of the reproductive cycle of the M13 bacteriophage is studied in more detail, namely the interaction of the major coat protein (MW 5240) with lipid bilayers. During the infection process is the major coat protein of M13 bacteriophage stored in the cytoplasm

  2. The evolution of lipids

    Science.gov (United States)

    Itoh, Y. H.; Sugai, A.; Uda, I.; Itoh, T.

    2001-01-01

    Living organisms on the Earth which are divided into three major domains - Archaea, Bacteria, and Eucarya, probably came from a common ancestral cell. Because there are many thermophilic microorganisms near the root of the universal phylogenetic tree, the common ancestral cell should be considered to be a thermophilic microorganism. The existence of a cell is necessary for the living organisms; the cell membrane is the essential structural component of a cell, so its amphiphilic property is vital for the molecule of lipids for cell membranes. Tetraether type glycerophospholipids with C 40 isoprenoid chains are major membrane lipids widely distributed in archaeal cells. Cyclization number of C 40 isoprenoid chains in thermophilic archaea influences the fluidity of lipids whereas the number of carbons and degree of unsaturation in fatty acids do so in bacteria and eucarya. In addition to the cyclization of the tetraether lipids, covalent bonding of two C 40 isoprenoid chains was found in hyperthermophiles. These characteristic structures of the lipids seem to contribute to their fundamental physiological roles in hyperthermophiles. Stereochemical differences between G-1-P archaeal lipids and G-3-P bacterial and eucaryal lipids might have occured by the function of some proteins long after the first cell was developed by the reactions of small organic molecules. We propose that the structure of lipids of the common ancestral cell may have been similar to those of hyperthermophilic archaea.

  3. Lipid profile in cerebrovascular accidents.

    Science.gov (United States)

    Togha, Mansoureh; Gheini, Mohamad Reza; Ahmadi, Babak; Khashaiar, Patricia; Razeghi, Soodeh

    2011-01-01

    Changes in the lipid profile have been suggested as a risk factor for developing ischemic stroke. Their role in intra-cerebral hemorrhage, however, is not clear. The present study was designed to evaluate the lipid profile levels of patients who had experienced an acute stroke during the first 24-hour and to compare these levels in different patients suffering from the stroke, either hemorrhagic or ischemic, and healthy individuals. In this cross-sectional study, 258 consecutive patients with acute stroke admitted to the neurology department of our center during September 2006 and September 2007 were studied. As for the control group, 187 apparently healthy subjects living in the same community and matched for age and sex were selected. Lipid profile was measured and compared between the three groups. In the patients' group, 65 suffered from hemorrhagic stroke (group 1) and the other 193 had ischemic stroke (group 2). Except for TG values, there was no significant difference among the ischemic and hemorrhagic lipid profile. Age, cholesterol, and LDL influenced the risk of developing an ischemic stroke; TG was not reported as a risk factor or a protective one. While the comparison of data retrieved from patients suffering from hemorrhagic strokes with the controls, revealed LDL as the risk factor contributing to the development of ICH whereas TG was reported as a protective factor. It could be concluded that LDL level can be considered as a risk factor for both ischemic and hemorrhagic cerebral events.

  4. Electroporation of Skin Stratum Corneum Lipid Bilayer and Molecular Mechanism of Drug Transport: A Molecular Dynamics Study.

    Science.gov (United States)

    Gupta, Rakesh; Rai, Beena

    2018-04-30

    Skin electroporation has been used significantly to increase the drug permeation. However, molecular mechanism, which resulted in enhancement of flux through skin, is still not known. In this study, extensive atomistic molecular dynamics simulation of skin lipids (made up of ceramide (CER), cholesterol (CHOL) and free fatty acid (FFA)) have been performed at various external electric field. We show for the first time the pore formation in the skin lipid bilayer during the electroporation. We show the effect of applied external electrical field on the pore formation dynamics in lipid bilayer of different size and composition. The pore formation and resealing kinetics were different and was found to be highly dependent on the composition of skin lipid bilayer. The pore formation time decreased with increase in the bilayer size. The pore sustaining electric field was found to be in the range of 0.20-0.25 V/nm for equimolar CER, CHOL and FFA lipid bilayer. The skin lipid bilayer (1:1:1), sealed itself within 20 ns after the removal of external electric field. We also present the molecular mechanism of enhancement of drug permeation in the presence of external field as compared to the passive diffusion. The molecular level understanding obtained here could help in optimizing/designing the electroporation experiments for effective drug delivery. For a given skin composition and size of drug molecule, the combination of pore formation time and pore growth model can be used to know aproiri the desired electric field and time for application of electric field.

  5. Evaluation of various solvent systems for lipid extraction from wet microalgal biomass and its effects on primary metabolites of lipid-extracted biomass.

    Science.gov (United States)

    Ansari, Faiz Ahmad; Gupta, Sanjay Kumar; Shriwastav, Amritanshu; Guldhe, Abhishek; Rawat, Ismail; Bux, Faizal

    2017-06-01

    Microalgae have tremendous potential to grow rapidly, synthesize, and accumulate lipids, proteins, and carbohydrates. The effects of solvent extraction of lipids on other metabolites such as proteins and carbohydrates in lipid-extracted algal (LEA) biomass are crucial aspects of algal biorefinery approach. An effective and economically feasible algae-based oil industry will depend on the selection of suitable solvent/s for lipid extraction, which has minimal effect on metabolites in lipid-extracted algae. In current study, six solvent systems were employed to extract lipids from dry and wet biomass of Scenedesmus obliquus. To explore the biorefinery concept, dichloromethane/methanol (2:1 v/v) was a suitable solvent for dry biomass; it gave 18.75% lipids (dry cell weight) in whole algal biomass, 32.79% proteins, and 24.73% carbohydrates in LEA biomass. In the case of wet biomass, in order to exploit all three metabolites, isopropanol/hexane (2:1 v/v) is an appropriate solvent system which gave 7.8% lipids (dry cell weight) in whole algal biomass, 20.97% proteins, and 22.87% carbohydrates in LEA biomass. Graphical abstract: Lipid extraction from wet microalgal biomass and biorefianry approach.

  6. Radiolabelling studies on the lipid metabolism in the marine brown alga Dictyopteris membranacea

    International Nuclear Information System (INIS)

    Hofmann, M.; Eichenberger, W.

    1998-01-01

    The lipid metabolism of the marine brown alga D. membranacea was investigated using [2- 14 C]acetate, [1- 14 C]myristate, [1- 14 C]oleate and [1- 14 C]arachidonate as precursors. On incubation with [2- 14 C]acetate, 18:1 and 16:0 were the main products formed by de novo synthesis and incorporated into polar lipids. With all the exogenous substrates used, DGTA was strongly labelled and the subsequent rapid turnover of radioactivity suggested a key role for this lipid in the redistribution of acyl chains and most likely also in the biosynthesis of the eukaryotic galactolipids produced in the absence of PC. In the glycolipids a continuous accumulation of radioactivity was observed with all the substrates used. The labelling kinetics of molecular species of MGDG suggested the desaturation of 18:1 to 18:4 and of 20:4 (n-6) to 20:5 (n-3) acids on this lipid. Both PG and PE were primary acceptors of de novo synthesized fatty acids and exogenous [1- 14 C]oleate, but no evidence exists for a further processing of acyl chains on these lipids. TAG, although strongly labelled with all exogenous [1- 14 C]acids, was not labelled when [2- 14 C]acetate was used as a precursor indicating the flux of endogenous fatty acids to be different of that of exogenously supplied fatty acids. (author)

  7. Structural characterization and lipid composition of acquired cholesteatoma

    DEFF Research Database (Denmark)

    Bloksgaard, Maria; Svane-Knudsen, Viggo; Sørensen, Jens A

    2012-01-01

    HYPOTHESIS: The goal of this work is to characterize the morphology and lipid composition of acquired cholesteatoma. We hypothesize that constitutive lipid membranes are present in the cholesteatoma and resemble those found in human skin stratum corneum. METHODS: We performed a comparative...... noninvasive structural and lipid compositional study of acquired cholesteatoma and control human skin using multiphoton excitation fluorescence microscopy-related techniques and high-performance thin-layer chromatography. RESULTS: The structural arrangement of the cholesteatoma is morphologically invariant...... along a depth of more than 200 μm and resembles the stratum corneum of hyperorthokeratotic skin. Lipid compositional analyses of the cholesteatoma show the presence of all major lipid classes found in normal skin stratum corneum (ceramides, long chain fatty acids, and cholesterol). Consistent with this...

  8. Structural transition in a lipid-water liquid system

    International Nuclear Information System (INIS)

    Bulavin, L.A.; Solovjov, D.V.; Solovjov, D.V.; Gorshkova, Yu.Je.; Zhigunov, O.M.; Ivan'kov, O.I.; Ivan'kov, O.I.; Gordelij, V.I.; Gordelij, V.I.; Gordelij, V.I.; Gordelij, V.I.; Kuklin, O.I.; Kuklin, O.I.

    2012-01-01

    Small-angle X-ray scattering technique has been used to study multilayer lipid membranes of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and the 3:1-mixture DPPC/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) in excess water. The temperature dependences of the repetition period for lipid bilayers in the temperature range 20-55 o C are obtained. A comparative analysis of the scattering curves obtained for multilayer membranes showed that, below a temperature of 40 o C , there emerges an additional ordering with a repetition period of 66 A in the lipid mixture, which we associate with the lipid phase separation. A disappearance of the so-called ripple (wave-like) phase of DPPC lipid in the mixture is also observed.

  9. LIPID ACCUMULATION OF CHLORELLA VULGARIS UNDER DIFFERENT PHOSPHATE CONCENTRATIONS

    Directory of Open Access Journals (Sweden)

    Magdalena Karolina Rokicka

    2017-04-01

    Full Text Available The cultivation and utilization of microalgae is now a intensively developing area of research. Some species of microalgae, under appropriate conditions, accumulate large amounts of lipids in the cells. This lipids have a suitable profile of fatty acids for biodiesel production. The culture of microalgae for lipids accumulation should be performed in certain physicochemical conditions. The aim of the study was to determine the effect of variable ortophophates concentrations in the culture medium for lipids accumulation of microalgae Chlorella vulgaris and to determine of parameters of the phosphoric shock in the medium. The study confirmed the possibility of the use of the phosphoric shock in the medium to maximize lipids accumulation by the microalgae Chlorella vulgaris. In the study, 45.23% of the oil was obtained from the biomass from the culture with phosphoric shock in the medium and 18% less of the oil was obtained from the biomass from the standard culture.

  10. Lipids and membrane lateral organization

    Directory of Open Access Journals (Sweden)

    Sandro eSonnino

    2010-11-01

    Full Text Available Shortly after the elucidation of the very basic structure and properties of cellular membranes, it became evident that cellular membranes are highly organized structures with multiple and multi-dimensional levels of order. Very early observations suggested that the lipid components of biological membranes might be active players in the creations of these levels of order. In the late 80’s, several different and diverse experimental pieces of evidence coalesced together giving rise to the lipid raft hypothesis. Lipid rafts became enormously (and, in the opinion of these authors, sometimes acritically popular, surprisingly not just within the lipidologist community (who is supposed to be naturally sensitive to the fascination of lipid rafts. Today, a PubMed search using the key word lipid rafts returned a list of 3767 papers, including 690 reviews (as a term of comparison, searching over the same time span for a very hot lipid-related key word, ceramide returned 6187 hits with 799 reviews, and a tremendous number of different cellular functions have been described as lipid raft-dependent. However, a clear consensus definition of lipid raft has been proposed only in recent times, and the basic properties, the ruling forces, and even the existence of lipid rafts in living cells have been recently matter of intense debate. The scenario that is gradually emerging from the controversies elicited by the lipid raft hypothesis emphasize multiple roles for membrane lipids in determining membrane order, that encompasses their tendency to phase separation but are clearly not limited to this. In this review, we would like to re-focus the attention of the readers on the importance of lipids in organizing the fine structure of cellular membranes.

  11. Engineering the lipid layer of lipid-PLGA hybrid nanoparticles for enhanced in vitro cellular uptake and improved stability.

    Science.gov (United States)

    Hu, Yun; Hoerle, Reece; Ehrich, Marion; Zhang, Chenming

    2015-12-01

    Lipid-polymer hybrid nanoparticles (NPs), consisting of a polymeric core and a lipid shell, have been intensively examined as delivery systems for cancer drugs, imaging agents, and vaccines. For applications in vaccine particularly, the hybrid NPs need to be able to protect the enclosed antigens during circulation, easily be up-taken by dendritic cells, and possess good stability for prolonged storage. However, the influence of lipid composition on the performance of hybrid NPs has not been well studied. In this study, we demonstrate that higher concentrations of cholesterol in the lipid layer enable slower and more controlled antigen release from lipid-poly(lactide-co-glycolide) acid (lipid-PLGA) NPs in human serum and phosphate buffered saline (PBS). Higher concentrations of cholesterol also promoted in vitro cellular uptake of hybrid NPs, improved the stability of the lipid layer, and protected the integrity of the hybrid structure during long-term storage. However, stabilized hybrid structures of high cholesterol content tended to fuse with each other during storage, resulting in significant size increase and lowered cellular uptake. Additional experiments demonstrated that PEGylation of NPs could effectively minimize fusion-caused size increase after long term storage, leading to improved cellular uptake, although excessive PEGylation will not be beneficial and led to reduced improvement. This paper reports the engineering of the lipid layer that encloses a polymeric nanoparticle, which can be used as a carrier for drug and vaccine molecules for targeted delivery. We demonstrated that the concentration of cholesterol is critical for the stability and uptake of the hybrid nanoparticles by dendritic cells, a targeted cell for the delivery of immune effector molecules. However, we found that hybrid nanoparticles with high cholesterol concentration tend to fuse during storage resulting in larger particles with decreased cellular uptake. This problem is

  12. Proteomic analysis of oil bodies in mature Jatropha curcas seeds with different lipid content.

    Science.gov (United States)

    Liu, Hui; Wang, Cuiping; Chen, Fan; Shen, Shihua

    2015-01-15

    To reveal the difference among three mature Jatropha curcas seeds (JcVH, variant with high lipid content; JcW, wild type and JcVL, variant with low lipid content) with different lipid content, comparative proteomics was employed to profile the changes of oil body (OB) associated protein species by using gels-based proteomic technique. Eighty-three protein species were successfully identified through LTQ-ES-MS/MS from mature JcW seeds purified OBs. Two-dimensional electrophoresis analysis of J. curcas OB associated protein species revealed they had essential interactions with other organelles and demonstrated that oleosin and caleosin were the most abundant OB structural protein species. Twenty-eight OB associated protein species showed significant difference among JcVH, JcW and JcVL according to statistical analysis. Complementary transient expression analysis revealed that calcium ion binding protein (CalBP) and glycine-rich RNA binding protein (GRP) were well targeted in OBs apart from the oleosins. This study demonstrated that ratio of lipid content to caleosins abundance was involved in the regulation of OB size, and the mutant induced by ethylmethylsulfone treatment might be related to the caleosin like protein species. These findings are important for biotechnological improvement with the aim to alter the lipid content in J. curcas seeds. The economic value of Jatropha curcas largely depends on the lipid content in seeds which are mainly stored in the special organelle called oil bodies (OBs). In consideration of the biological importance and applications of J. curcas OB in seeds, it is necessary to further explore the components and functions of J. curcas OBs. Although a previous study concerning the J. curcas OB proteome revealed oleosins were the major OB protein component and additional protein species were similar to those in other oil seed plants, these identified OB associated protein species were corresponding to the protein bands instead of protein

  13. Major Lipid Body Protein: A Conserved Structural Component of Lipid Body Accumulated during Abiotic Stress in S. quadricauda CASA-CC202

    International Nuclear Information System (INIS)

    Javee, Anand; Sulochana, Sujitha Balakrishnan; Pallissery, Steffi James; Arumugam, Muthu

    2016-01-01

    Abiotic stress in oleaginous microalgae enhances lipid accumulation, which is stored in a specialized organelle called lipid droplets (LDs). Both the LDs or lipid body are enriched with major lipid droplet protein (MLDP). It serves as a major structural component and also plays a key role in recruiting other proteins and enzymes involved in lipid body maturation. In the present study, the presence of MLDP was detected in two abiotic stress condition namely nitrogen starvation and salt stress condition. Previous research reveals that nitrogen starvation enhances lipid accumulation. Therefore, the effect of salt on growth, biomass yield, and fatty acid profile is studied in detail. The specific growth rate of Scenedesmus quadricauda under the salt stress of 10mM concentration is about 0.174 μ and in control, the SGR is 0.241 μ. An increase in the doubling time of the cells shows that the rate of cell division decreases during salt stress (2.87–5.17). The dry biomass content also decreased drastically at 50mM salt-treated cells (129 mg/L) compared to control (236 mg/L) on the day 20. The analysis of fatty acid composition also revealed that there is a 20% decrease in the saturated fatty acid level and 19.9% increment in monounsaturated fatty acid level, which makes salt-mediated lipid accumulation as a suitable biodiesel precursor.

  14. Major Lipid Body Protein: A Conserved Structural Component of Lipid Body Accumulated during Abiotic Stress in S. quadricauda CASA-CC202

    Energy Technology Data Exchange (ETDEWEB)

    Javee, Anand [Biotechnology Division, National Institute for Interdisciplinary Science and Technology (NIIST), Council of Scientific and Industrial Research (CSIR), Trivandrum (India); Sulochana, Sujitha Balakrishnan [Biotechnology Division, National Institute for Interdisciplinary Science and Technology (NIIST), Council of Scientific and Industrial Research (CSIR), Trivandrum (India); Academy of Scientific and Innovative Research (AcSIR), New Delhi (India); Pallissery, Steffi James [Biotechnology Division, National Institute for Interdisciplinary Science and Technology (NIIST), Council of Scientific and Industrial Research (CSIR), Trivandrum (India); Arumugam, Muthu, E-mail: arumugam@niist.res.in [Biotechnology Division, National Institute for Interdisciplinary Science and Technology (NIIST), Council of Scientific and Industrial Research (CSIR), Trivandrum (India); Academy of Scientific and Innovative Research (AcSIR), New Delhi (India)

    2016-11-23

    Abiotic stress in oleaginous microalgae enhances lipid accumulation, which is stored in a specialized organelle called lipid droplets (LDs). Both the LDs or lipid body are enriched with major lipid droplet protein (MLDP). It serves as a major structural component and also plays a key role in recruiting other proteins and enzymes involved in lipid body maturation. In the present study, the presence of MLDP was detected in two abiotic stress condition namely nitrogen starvation and salt stress condition. Previous research reveals that nitrogen starvation enhances lipid accumulation. Therefore, the effect of salt on growth, biomass yield, and fatty acid profile is studied in detail. The specific growth rate of Scenedesmus quadricauda under the salt stress of 10mM concentration is about 0.174 μ and in control, the SGR is 0.241 μ. An increase in the doubling time of the cells shows that the rate of cell division decreases during salt stress (2.87–5.17). The dry biomass content also decreased drastically at 50mM salt-treated cells (129 mg/L) compared to control (236 mg/L) on the day 20. The analysis of fatty acid composition also revealed that there is a 20% decrease in the saturated fatty acid level and 19.9% increment in monounsaturated fatty acid level, which makes salt-mediated lipid accumulation as a suitable biodiesel precursor.

  15. Lipid Fingerprinting in Mild versus Severe Forms of Gestational Diabetes Mellitus.

    Directory of Open Access Journals (Sweden)

    Bárbara Yasmin Gueuvoghlanian-Silva

    Full Text Available The blood serum lipid profile of women with Gestational Diabetes Mellitus (GDM is still under study. There are no data on the serum lipid profile of GDM patients with more severe (insulin treated compared to milder forms (diet treated GDM. The aim of our study was to analyze the blood serum lipid profile of patients with milder versus more severe forms of GDM and to compare these findings with those of healthy pregnant women. This cross-sectional analytical study included 30 insulin-treated GDM, 30 diet-only GDM and 30 healthy pregnant women. Serum lipid was extracted from the 90 participants and their lipid profiles were analyzed by lipid fingerprinting using liquid-chromatography-mass spectrometry. A total of 143 parent ions were differentially represented in each of the three groups, belonging to the following classes: Glycerophospholipids, Sterol Lipids, Sphingolipids, Prenol Lipids, Fatty Acyls and Glycerolipids. There were significant differences in the lipid profiles of healthy pregnant women compared to GDM patients and also between milder versus more severe forms of GDM. There are marked differences in lipid fingerprinting between healthy pregnant women compared to those with GDM in the third trimester. Moreover, the lipid profile of women with more severe forms of GDM differs considerably from that of women with milder forms of GDM. These findings may be useful to help clarify the pathogenesis of milder and more severe forms of GDM.

  16. Prevalence of dyslipidemia according to the nutritional status in a representative sample of São Paulo.

    Science.gov (United States)

    Garcez, Marcela Riccioppo; Pereira, Jaqueline Lopes; Fontanelli, Mariane de Mello; Marchioni, Dirce Maria Lobo; Fisberg, Regina Mara

    2014-12-01

    Overweight is one of the major public health problems in Brazil; it is associated with dyslipidemia, which is an important risk factor for cardiovascular diseases. To evaluate the lipid profile of residents of the municipality of São Paulo, state of São Paulo, according to the nutritional status. Data from the population-based cross-sectional study ISA-Capital 2008 on a sample of residents of São Paulo were used. Participants were categorized into groups according to body mass index and age range. The levels of total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, and non-HDL cholesterol were measured. The association between lipid profile, nutricional status, and waist circumference was investigated. The data were processed using the survey mode of the Stata 11.0 software. The prevalence of any type of dyslipidemia in the population was 59.74%, with low HDL-cholesterol dyslipidemia being the most common type. Not overweight individuals had higher mean levels of HDL-cholesterol and lower levels of LDL-cholesterol, total cholesterol, triglycerides, and non-HDL cholesterol when compared with the overweight group. The rate of inadequacy of these variables was higher in the overweight individuals, regardless of the age group, to the exception of LDL-cholesterol in the adults and elderly. A higher prevalence of isolated hypertriglyceridemia was observed in individuals with higher waist circumference among the adults and the total population. The results indicate an association between dyslipidemia and overweight in the population of the city of São Paulo. The most prevalent dyslipidemia in this population was low HDL-cholesterol.

  17. Computational Modeling of Lipid Metabolism in Yeast

    Directory of Open Access Journals (Sweden)

    Vera Schützhold

    2016-09-01

    Full Text Available Lipid metabolism is essential for all major cell functions and has recently gained increasing attention in research and health studies. However, mathematical modeling by means of classical approaches such as stoichiometric networks and ordinary differential equation systems has not yet provided satisfactory insights, due to the complexity of lipid metabolism characterized by many different species with only slight differences and by promiscuous multifunctional enzymes.Here, we present a object-oriented stochastic model approach as a way to cope with the complex lipid metabolic network. While all lipid species are treated objects in the model, they can be modified by the respective converting reactions based on reaction rules, a hybrid method that integrates benefits of agent-based and classical stochastic simulation. This approach allows to follow the dynamics of all lipid species with different fatty acids, different degrees of saturation and different headgroups over time and to analyze the effect of parameter changes, potential mutations in the catalyzing enzymes or provision of different precursors. Applied to yeast metabolism during one cell cycle period, we could analyze the distribution of all lipids to the various membranes in time-dependent manner.The presented approach allows to efficiently treat the complexity of cellular lipid metabolism and to derive conclusions on the time- and location-dependent distributions of lipid species and their properties such as saturation. It is widely applicable, easily extendable and will provide further insights in healthy and diseased states of cell metabolism.

  18. Sex-Specific Associations Between Thyrotropin and Serum Lipid Profiles

    DEFF Research Database (Denmark)

    Meisinger, Christa; Ittermann, Till; Tiller, Daniel

    2014-01-01

    BACKGROUND: Population-based studies investigating the sex-specific association between thyrotropin (TSH) levels and serum lipid concentrations are scarce. We examined the association between TSH and total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL......) cholesterol, and triglycerides in men and women from the general population. Furthermore, the association with TSH outside and within the reference range and lipid levels was studied. METHODS: Individual data of 13,571 men and women without lipid medication of four population-based studies conducted...... in Western European adults were pooled for cross-sectional analyses. The association between TSH levels and lipid concentrations were analyzed by calculating sex-specific multivariable median regression models. RESULTS: In the pooled population, serum TSH levels were significantly positively associated...

  19. Melanoidins-kerogen precursors and geochemical lipid sinks: a study using pyrolysis gas chromatography (PGC)

    Energy Technology Data Exchange (ETDEWEB)

    Larter, S R; Douglas, A G

    1980-12-01

    Melanoidins, acidic polymeric products of amino acid/sugar condensation reactions, are shown to be capable of reacting with and binding functionalized lipid molecules. Pyrolysis gas chromatography is used to monitor the inclusion of lipids (alcohols and acids) into, and to monitor the changes in composition caused by artificial diagenesis of, the melanoidins. Artificial diagenesis of the lipid-containing melanoidins produces a material resembling kerogen. The possible role of melanoidins in the formation of krogen is discussed as are internal transformations within kerogens during diagenesis.

  20. Preparation of ultra-fine powders from polysaccharide-coated solid lipid nanoparticles and nanostructured lipid carriers by innovative nano spray drying technology.

    Science.gov (United States)

    Wang, Taoran; Hu, Qiaobin; Zhou, Mingyong; Xue, Jingyi; Luo, Yangchao

    2016-09-10

    In this study, five polysaccharides were applied as natural polymeric coating materials to prepare solid lipid nanoparticles (SLN) and nanostructure lipid carriers (NLC), and then the obtained lipid colloidal particles were transformed to solid powders by the innovative nano spray drying technology. The feasibility and suitability of this new technology to generate ultra-fine lipid powder particles were evaluated and the formulation was optimized. The spray dried SLN powder exhibited the aggregated and irregular shape and dimension, but small, uniform, well-separated spherical powder particles of was obtained from NLC. The optimal formulation of NLC was prepared by a 20-30% oleic acid content with carrageenan or pectin as coating material. Therefore, nano spray drying technology has a potential application to produce uniform, spherical, and sub-microscale lipid powder particles when the formulation of lipid delivery system is appropriately designed. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Artificial Lipid Membranes: Past, Present, and Future.

    Science.gov (United States)

    Siontorou, Christina G; Nikoleli, Georgia-Paraskevi; Nikolelis, Dimitrios P; Karapetis, Stefanos K

    2017-07-26

    The multifaceted role of biological membranes prompted early the development of artificial lipid-based models with a primary view of reconstituting the natural functions in vitro so as to study and exploit chemoreception for sensor engineering. Over the years, a fair amount of knowledge on the artificial lipid membranes, as both, suspended or supported lipid films and liposomes, has been disseminated and has helped to diversify and expand initial scopes. Artificial lipid membranes can be constructed by several methods, stabilized by various means, functionalized in a variety of ways, experimented upon intensively, and broadly utilized in sensor development, drug testing, drug discovery or as molecular tools and research probes for elucidating the mechanics and the mechanisms of biological membranes. This paper reviews the state-of-the-art, discusses the diversity of applications, and presents future perspectives. The newly-introduced field of artificial cells further broadens the applicability of artificial membranes in studying the evolution of life.

  2. Use of quantitative optical imaging to examine the role of cholesterol-rich lipid raft microdomains in the migration of breast cancer cells

    Science.gov (United States)

    You, Minghai; Chen, Jianling; Wang, Shaobing; Dong, Shiqing; Wang, Yuhua; Xie, Shusen; Wang, Zhengchao; Yang, Hongqin

    2018-04-01

    Lipid rafts have been extensively studied and shown to be involved in many cancers, including breast cancer. However, the exact role of lipid rafts in the migration of breast cancer cells remains unclear. This study was designed to examine lipid rafts (cholesterol) in the plasma membrane of breast cancer cells (MDA-MB-231 and MCF-7) and normal breast epithelial cells (MCF-10A) through generalized polarization values, and further investigate the role of cholesterol-rich lipid rafts in the migration of breast cancer cells. The results showed that the plasma membrane in breast cancer cells was more orderly than that in normal epithelial cells; this was correlated with expression changes of matrix metallopeptidase 9 (MMP-9) and urokinase-type plasminogen activator receptor (uPAR), the markers of cancer cell migration. Moreover, the breast cancer cells were more sensitive to the reagent that induced cholesterol depletion than the normal breast epithelial cells, while the capacity of cancer cells to migrate decreased significantly according to changes in MMP-9 and uPAR expression. To our best knowledge, this is the first demonstration of the relationship between cholesterol-rich lipid rafts and the migration of breast cancer cells; it could be useful for the prevention of breast cancer and early treatment through reduction of the level of cholesterol in the plasma membrane of the cells.

  3. Gene therapy for lipid disorders

    Directory of Open Access Journals (Sweden)

    Rader Daniel J

    2000-10-01

    Full Text Available Abstract Lipid disorders are associated with atherosclerotic vascular disease, and therapy is associated with a substantial reduction in cardiovascular events. Current approaches to the treatment of lipid disorders are ineffective in a substantial number of patients. New therapies for refractory hypercholesterolemia, severe hypertriglyceridemia, and low levels of high-density lipoprotein cholesterol are needed: somatic gene therapy is one viable approach. The molecular etiology and pathophysiology of most of the candidate diseases are well understood. Animal models exist for the diseases and in many cases preclinical proof-of-principle studies have already been performed. There has been progress in the development of vectors that provide long-term gene expression. New clinical gene therapy trials for lipid disorders are likely to be initiated within the next few years.

  4. In vitro study of (1-14C)-acetate incorporation into lipids of liver slices in experimental diabetes

    International Nuclear Information System (INIS)

    Greco, A.V.; Mingrone, G.; Peruzzi, E.; Orlando, P.

    1981-01-01

    The effect of insulin deficiency on lipid synthesis in the liver of normal rats, diabetic rats by alloxan and pancreatectomized rats was studied in vitro using (1- 14 C)-acetate as lipid precursor. Insulin deficiency induces an increased incorporation of (1- 14 C)-acetate into triglycerides in rat liver. This is particularly evident in pancreatectomized rats with respect to alloxan diabetic rats. It is concluded that in experimental diabetes an atherogenous metabolic pattern is elaborated by the liver. (author)

  5. Relationship between serum lipid concentrations and posttraumatic stress symptoms in the bereaved after the Sewol ferry disaster: A prospective cohort study.

    Science.gov (United States)

    Tae, Hyejin; Huh, Hyu Jung; Hwang, Jihyun; Chae, Jeong-Ho

    2018-05-16

    The objective of this study was to investigate the relationship between serum lipid concentrations and PTSD symptoms in the bereaved after a traumatic familial loss. Eighteen months after the Sewol ferry disaster, 107 subjects who experienced traumatic losses as a result of the accident completed a mental and medical survey as well as laboratory tests for lipid profiles. At 30 months after the trauma, a total of 64 individuals completed a follow-up psychometric survey and biochemical measurements. We performed multiple linear regression analyses, examining the association between PTSD symptoms and lipid profiles. Other potential influences on lipid profiles such as metabolic risk factors, demographic risk factors, and underlying medical history were accounted for. Participants reporting clinically significant PTSD symptoms exhibited lower serum HDL-C levels than those without PTSD symptoms. In addition, we found that the severity of PTSD symptoms and sex could explain the changes in lipid profiles independently of other possible risk factors of changes. The results of this study suggest that PTSD symptoms may contribute to an increased risk for developing metabolic syndrome via detrimental changes in lipid concentrations. Routine screening and multidisciplinary management to prevent metabolic syndrome in individuals who experience traumatic losses would therefore be valuable. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Applications of lipid nanocarriers for solid tumors therapy: literature review

    International Nuclear Information System (INIS)

    Oliveira, Lidiane Correia de; Souza, Leonardo Gomes; Marreto, Ricardo Neves; Lima, Eliana Martins; Taveira, Stephania Fleury; Taveira, Eliseu Jose Fleury

    2012-01-01

    Introduction: Lipid nanocarriers are systems used to target drugs to its site of action and have attracted attention of the scientific community because they are biocompatible and biodegradable. These systems can target drugs to solid tumors, providing sustained drug release in the site of action, thus increasing the utility of the antineoplastic chemotherapy. Objective: To review the available literature on in vivo experiments with lipid nanocarriers containing cytotoxic drugs for solid tumors treatment. Method: A search study was carried out in Pubmed R database from 2007 to 2011, with subject descriptors: liposomes, lipid nanoparticles, cancer and in vivo, with the boolean operator 'and' among them, in English. Results: 1,595 papers related to the use of liposomes and 77 related to lipid nanoparticles were found. Few studies reported in vivo experiments with lipid nanoparticles (28 papers) compared to liposomes (472 papers), since liposomes were developed two decades before lipid nanoparticles. Four liposomal medicines have already been approved and are used in the clinic while only one medicine containing lipid nanoparticles is in phase I of clinical studies. Conclusion: The number of papers related to the use of nanotechnology for cancer treatment is increasing rapidly, making important to know the different kinds of nanocarriers and, especially, those which are already used in the clinic. There are only few clinical studies on lipid nanocarriers; however, these systems present an enormous potential to improve the clinical practice in oncology. (author)

  7. A COMPARATIVE STUDY OF EFFECTS OF SMOKING ON LIPID PROFILE AMONG HEALTHY SMOKERS AND NON-SMOKERS

    Directory of Open Access Journals (Sweden)

    Girish I

    2018-02-01

    Full Text Available BACKGROUND Coronary artery disease forms a major non-communicable disease in both developed and developing countries. In western countries, older age groups are affected whereas in our country India, it is common among younger age group. Many risk factors have been evaluated. Cigarette smoking contributes for major risk factor for coronary artery disease, atherosclerosis and peripheral vascular disorders. Mechanism of causing coronary artery disease is multifactorial, it has major adverse effects on lipid profile and homocysteine levels which are again risk factors for coronary artery disease. Hence, this study was undertaken to compare the effects of smoking cigarettes/beedis on lipid profile among smokers and non-smokers. MATERIALS AND METHODS It was a case - control study carried out on 50 healthy smokers and 50 healthy age and weight matched non-smokers attending the medicine OPD of Basaveshwara Medical College, Chitradurga from January to April 2017. Subjects in both groups were in the age range of 25-35 yrs., with no history of alcohol abuse, diabetes mellitus, hypertension, hepatic impairment, renal disease or history of drug intake which alter the lipid profile. RESULTS The mean serum total cholesterol, serum triglycerides, serum LDL- cholesterol & serum VLDL-cholesterol were significantly higher while antiatherogenic serum HDL cholesterol were significantly lower in smokers when compared with non-smokers and it was statistically significant (p<0.001. CONCLUSION Present study shows a statistically significant relationship between cigarette smoking and increased lipid profile. Thus, chronic smokers are at the significant risk of developing Coronary Heart Disease. So, smokers should be counselled and encouraged to quit smoking and adopt a healthier life style.

  8. LipidMatch: an automated workflow for rule-based lipid identification using untargeted high-resolution tandem mass spectrometry data.

    Science.gov (United States)

    Koelmel, Jeremy P; Kroeger, Nicholas M; Ulmer, Candice Z; Bowden, John A; Patterson, Rainey E; Cochran, Jason A; Beecher, Christopher W W; Garrett, Timothy J; Yost, Richard A

    2017-07-10

    Lipids are ubiquitous and serve numerous biological functions; thus lipids have been shown to have great potential as candidates for elucidating biomarkers and pathway perturbations associated with disease. Methods expanding coverage of the lipidome increase the likelihood of biomarker discovery and could lead to more comprehensive understanding of disease etiology. We introduce LipidMatch, an R-based tool for lipid identification for liquid chromatography tandem mass spectrometry workflows. LipidMatch currently has over 250,000 lipid species spanning 56 lipid types contained in in silico fragmentation libraries. Unique fragmentation libraries, compared to other open source software, include oxidized lipids, bile acids, sphingosines, and previously uncharacterized adducts, including ammoniated cardiolipins. LipidMatch uses rule-based identification. For each lipid type, the user can select which fragments must be observed for identification. Rule-based identification allows for correct annotation of lipids based on the fragments observed, unlike typical identification based solely on spectral similarity scores, where over-reporting structural details that are not conferred by fragmentation data is common. Another unique feature of LipidMatch is ranking lipid identifications for a given feature by the sum of fragment intensities. For each lipid candidate, the intensities of experimental fragments with exact mass matches to expected in silico fragments are summed. The lipid identifications with the greatest summed intensity using this ranking algorithm were comparable to other lipid identification software annotations, MS-DIAL and Greazy. For example, for features with identifications from all 3 software, 92% of LipidMatch identifications by fatty acyl constituents were corroborated by at least one other software in positive mode and 98% in negative ion mode. LipidMatch allows users to annotate lipids across a wide range of high resolution tandem mass spectrometry

  9. The correlation between lipids ratio and degree of coronary artery stenosis.

    Science.gov (United States)

    Yang, Dan; Liu, Xianbao; Xiang, Meixiang

    2011-06-01

    The aim of the study was to explore the relationship between lipids ratio and the degree of coronary artery stenosis. According to the Gensini score of inpatients in the Cardiology Department of the Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China, from January 2008 to June 2010, a total of 207 patients (group 1: control group = 34 patients; group 2: 1-30 score group = 84 patients; group 3: 31-90 score group = 66 patients; and group 4: >90 score group = 23 patients) were enrolled, and the relationship between lipids and the degree of coronary artery stenosis was determined. Our study showed that the severity of coronary lesions was increased with the elevation of low-density lipoprotein cholesterol (LDL-C)/high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), LDL-C, triglycerides (TG), TC/HDL-C, TG/HDL-C and reduction of HDL-C. Compared with group 1, LDL-C/HDL-C, TC/HDL-C were significantly increased in groups 2, 3 and 4 (p value of TG, TG/HDL-C among groups 2, 3 and 4 (p > 0.05). Furthermore, the Pearson correlation analysis revealed that LDL-C/HDL-C (r = 0.54, p value of TG/HDL-C needs further study. Received for publication 25 October 2010; accepted for publication 14 April 2011.

  10. Amylose folding under the influence of lipids

    NARCIS (Netherlands)

    Lopez, Cesar A.; de Vries, Alex H.; Marrink, Siewert J.

    2012-01-01

    The molecular dynamics simulation technique was used to study the folding and complexation process of a short amylose fragment in the presence of lipids. In aqueous solution, the amylose chain remains as an extended left-handed helix. After the addition of lipids in the system, however, we observe

  11. [Lipid synthesis by an acidic acid tolerant Rhodotorula glutinis].

    Science.gov (United States)

    Lin, Zhangnan; Liu, Hongjuan; Zhang, Jian'an; Wang, Gehua

    2016-03-01

    Acetic acid, as a main by-product generated in the pretreatment process of lignocellulose hydrolysis, significantly affects cell growth and lipid synthesis of oleaginous microorganisms. Therefore, we studied the tolerance of Rhodotorula glutinis to acetic acid and its lipid synthesis from substrate containing acetic acid. In the mixed sugar medium containing 6 g/L glucose and 44 g/L xylose, and supplemented with acetic acid, the cell growth was not:inhibited when the acetic acid concentration was below 10 g/L. Compared with the control, the biomass, lipid concentration and lipid content of R. glutinis increased 21.5%, 171% and 122% respectively when acetic acid concentration was 10 g/L. Furthermore, R. glutinis could accumulate lipid with acetate as the sole carbon source. Lipid concentration and lipid yield reached 3.20 g/L and 13% respectively with the initial acetic acid concentration of 25 g/L. The lipid composition was analyzed by gas chromatograph. The main composition of lipid produced with acetic acid was palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid, including 40.9% saturated fatty acids and 59.1% unsaturated fatty acids. The lipid composition was similar to that of plant oil, indicating that lipid from oleaginous yeast R. glutinis had potential as the feedstock of biodiesel production. These results demonstrated that a certain concentration of acetic acid need not to be removed in the detoxification process when using lignocelluloses hydrolysate to produce microbial lipid by R. glutinis.

  12. Enhanced lipid extraction from microalgae in biodiesel production

    Directory of Open Access Journals (Sweden)

    Kim Myung-Gyun

    2017-01-01

    Full Text Available In order to secure more effective lipid extraction method, this research investigated new lipid extraction method using laser with absorbent and sought its optimum operation control. In addition, this study compared lipid extraction efficiency and FAME conversion rate between laser extraction method at optimum condition and existing extraction method. Results from experiments for optimizing lipid extraction method using laser showed that the maximum extraction efficiency (81.8% was attained when using laser with an output capacity of 75Wh/L. Extraction efficiency increased up to 90.8% when microwave treatment as pretreatment process was conducted. Addition of absorbents during lipid extraction process with laser showed higher extraction efficiency than laser and chemical method. It was also found that laser extraction method with absorbent had higher total fatty acid content (853.7 mg/g oil in extracted lipid than chemical extraction method (825.4 mg/g oil. Furthermore, it had the highest FAME conversion rate (94.2%.

  13. Temperature-controlled continuous production of all-trans retinoic acid-loaded solid lipid nanoparticles using static mixers

    Science.gov (United States)

    Shao, Wenyao; Yan, Mengwen; Chen, Tingting; Chen, Yuqing; Xiao, Zongyuan

    2017-04-01

    This work aims to develop a temperature-controlled continuous solvent emulsification-diffusion process to synthesize all-trans retinoic acid (ATRA)-loaded solid lipid nanoparticles (SLNs) using static mixers. ATRA-loaded SLNs of around 200 nm were obtained when the flow rates of the organic and aqueous phases were 50 ml min-1 and 500 ml min-1, respectively. It was found that the lipid concentration played a dominant role in the size of the obtained SLNs, and higher drug concentration resulted in relatively low entrapment efficiency. The encapsulation of ATRA in the SLNs was effective in improving its stability according to the photo-degradation test. The in vitro release of SLN was slow without an initial burst. This study demonstrates that the solvent emulsification-diffusion technique with static mixing is an effective method of producing SLNs, and could easily be scaled up for industrial applications. Highlights Higher lipid concentration leads to larger SLNs. SLN transformation occurs due to Ostwald ripening. The ATRA-loaded SLNs around 200 nm were successfully produced with static mixers. ATRA-loaded SLNs show better stability towards sunlight. ATRA in SLNs exhibited a relatively slow release rate without a significant initial burst.

  14. Basis of aggravated hepatic lipid metabolism by chronic stress in high-fat diet-fed rat.

    Science.gov (United States)

    Han, Ying; Lin, Min; Wang, Xiaobin; Guo, Keke; Wang, Shanshan; Sun, Mengfei; Wang, Jiao; Han, Xiaoyu; Fu, Ting; Hu, Yang; Fu, Jihua

    2015-03-01

    Our previous study has demonstrated that long-term stress, known as chronic stress (CS), can aggravate nonalcoholic fatty liver disease in high-fat diet (HFD)-fed rat. In this study, we tried to figure out which lipid metabolic pathways were impacted by CS in the HFD-fed rat. Male Sprague-Dawley rats (6 weeks of age, n = 8 per group) were fed with either standard diet or HFD with or without CS exposure for 8 weeks. Hepatic lipidosis, biochemical, hormonal, and lipid profile markers in serum and liver, and enzymes involved in de novo lipogenesis (DNL) of fatty acids (FAs) and cholesterol, β-oxidation, FAs uptake, triglycerides synthesis, and very low-density lipoprotein (VLDL) assembly in the liver were detected. CS exposure reduced hepatic lipidosis but further elevated hepatic VLDL content with aggravated dyslipidemia in the HFD-fed rats. There was a synergism between CS and HFD on VLDL production and dyslipidemia. PCR and western blot assays showed that CS exposure significantly promoted hepatic VLDL assembly in rats, especially in the HFD-fed rats, while it had little impact on DNL, β-oxidation, FAs uptake, and triglycerides synthesis in the HFD-fed rats. This phenomenon was in accordance with elevated serum glucocorticoid level. The critical influence of CS exposure on hepatic lipid metabolism in the HFD-fed rats is VLDL assembly which might be regulated by glucocorticoid.

  15. Role of Lipids in the Onset, Progression and Treatment of Periodontal Disease. A Systematic Review of Studies in Humans

    Directory of Open Access Journals (Sweden)

    Alfonso Varela-López

    2016-07-01

    Full Text Available The risk of different oral problems (root caries, tooth mobility, and tooth loss can be increased by the presence of periodontal disease, which has also been associated with a growing list of systemic diseases. The presence of some bacteria is the primary etiology of this disease; a susceptible host is also necessary for disease initiation. In this respect, the progression of periodontal disease and healing of the periodontal tissues can be modulated by nutritional status. To clarify the role of lipids in the establishment, progression, and/or treatment of this pathology, a systematic review was conducted of English-written literature in PubMed until May 2016, which included research on the relationship of these dietary components with the onset and progression of periodontal disease. According to publication type, randomized-controlled trials, cohort, case-control and cross-sectional studies were included. Among all the analyzed components, those that have any effect on oxidative stress and/or inflammation seem to be the most interesting according to current evidence. On one hand, there is quite a lot of information in favor of a positive role of n-3 fatty acids, due to their antioxidant and immunomodulatory effects. On the other hand, saturated fat-rich diets increase oxidative stress as well the as intensity and duration of inflammatory processes, so they must be avoided.

  16. Phytosterols, Lipid Administration, and Liver Disease During Parenteral Nutrition.

    Science.gov (United States)

    Zaloga, Gary P

    2015-09-01

    Phytosterols are plant-derived sterols that are structurally and functionally analogous to cholesterol in vertebrate animals. Phytosterols are found in many foods and are part of the normal human diet. However, absorption of phytosterols from the diet is minimal. Most lipid emulsions used for parenteral nutrition are based on vegetable oils. As a result, phytosterol administration occurs during intravenous administration of lipid. Levels of phytosterols in the blood and tissues may reach high levels during parenteral lipid administration and may be toxic to cells. Phytosterols are not fully metabolized by the human body and must be excreted through the hepatobiliary system. Accumulating scientific evidence suggests that administration of high doses of intravenous lipids that are high in phytosterols contributes to the development of parenteral nutrition-associated liver disease. In this review, mechanisms by which lipids and phytosterols may cause cholestasis are discussed. Human studies of the association of phytosterols with liver disease are reviewed. In addition, clinical studies of lipid/phytosterol reduction for reversing and/or preventing parenteral nutrition associated liver disease are discussed. © 2015 American Society for Parenteral and Enteral Nutrition.

  17. A simple HPLC method for the determination of halcinonide in lipid nanoparticles: development, validation, encapsulation efficiency, and in vitro drug permeation

    Directory of Open Access Journals (Sweden)

    Clarissa Elize Lopes

    2017-06-01

    Full Text Available ABSTRACT Halcinonide is a high-potency topical glucocorticoid used for skin inflammation treatments that presents toxic systemic effects. A simple and quick analytical method to quantify the amount of halcinonide encapsulated into lipid nanoparticles, such as polymeric lipid-core nanoparticles and solid lipid nanoparticles, was developed and validated regarding the drug's encapsulation efficiency and in vitro permeation. The development and validation of the analytical method were carried out using the high performance liquid chromatography with the UV detection at 239 nm. The validation parameters were specificity, linearity, precision and accuracy, limits of detection and quantitation, and robustness. The method presented an isocratic flow rate of 1.0 mL.min-1, a mobile phase methanol:water (85:15 v/v, and a retention time of 4.21 min. The method was validated according to international and national regulations. The halcinonide encapsulation efficiency in nanoparticles was greater than 99% and the in vitro drug permeation study showed that less than 9% of the drug permeated through the membrane, indicating a nanoparticle reservoir effect, which can reduce the halcinonide's toxic systemic effects. These studies demonstrated the applicability of the developed and validated analytical method to quantify halcinonide in lipid nanoparticles.

  18. Lipid composition of human meibum

    Directory of Open Access Journals (Sweden)

    R. Schnetler

    2013-12-01

    Full Text Available The structure and function of meibomian gland lipids in the tear film are highly complex. Evidence shows that the precorneal tear film consists of discrete layers: the inner mucin layer, the middle aqueous layer and the outer lipid layer. In this review we focus on the outer, biphasic lipid layer of the tear film which consists of a ‘thick’ outer, non-polar layer  and a ‘thin’ inner, polar layer. We discuss the main composition of the polar and non-polar lipids within meibum (wax esters, cholesteryl esters, mono-, di- and tri-acylglycerols, ceramides, phospholipids  et cetera. We address the composition of meibomian lipids in subjects suffering from various ocular diseases in comparison with the composition in healthy individuals. Further analysis is needed to determine whether a correlation exists between the etiology of various ocular diseases and the fluctuation on the lipids as well as to establish whether or not tear lipid analysis can be used as a diagnostic tool.

  19. Lipid ratio as a suitable tool to identify individuals with MetS risk: A case- control study.

    Science.gov (United States)

    Abbasian, Maryam; Delvarianzadeh, Mehri; Ebrahimi, Hossein; Khosravi, Farideh

    2017-11-01

    This study aimed to compare the serum lipids ratio in staff with and without metabolic syndrome (MetS) who were working in Shahroud University of Medical Sciences. This case-control study was conducted in 2015 on 499 personnel aged 30-60 years old. ATP III criteria were used to diagnose patients with MetS. The data were analyzed by using logistic regression and ROC curve. Mean lipid ratio was higher in individuals having the MetS in both sexes compared with those without. In addition, the mean levels of lipid ratios significantly increased with increasing number of MetS components in both sexes. Also it could be concluded that TG/HDL-C ratio is the best marker for the diagnosis of MetS in men and women. Moreover, the cut-off point for the TG/HDL-C was 2.86 in women and 4.03 in men. It was found that for any unit of increases in the TG/HDL-C, the risk of developing the MetS will increase by 2.12 times. TG/HDL-C ratio is found to be the best clinical marker for the diagnosis of MetS compare with other lipid ratios, therefore it is recommended to be used as a feasible tool to identify individuals with MetS risk. Copyright © 2016 Diabetes India. Published by Elsevier Ltd. All rights reserved.

  20. The TULIP superfamily of eukaryotic lipid-binding proteins as a mediator of lipid sensing and transport.

    Science.gov (United States)

    Alva, Vikram; Lupas, Andrei N

    2016-08-01

    The tubular lipid-binding (TULIP) superfamily has emerged in recent years as a major mediator of lipid sensing and transport in eukaryotes. It currently encompasses three protein families, SMP-like, BPI-like, and Takeout-like, which share a common fold. This fold consists of a long helix wrapped in a highly curved anti-parallel β-sheet, enclosing a central, lipophilic cavity. The SMP-like proteins, which include subunits of the ERMES complex and the extended synaptotagmins (E-Syts), appear to be mainly located at membrane contacts sites (MCSs) between organelles, mediating inter-organelle lipid exchange. The BPI-like proteins, which include the bactericidal/permeability-increasing protein (BPI), the LPS (lipopolysaccharide)-binding protein (LBP), the cholesteryl ester transfer protein (CETP), and the phospholipid transfer protein (PLTP), are either involved in innate immunity against bacteria through their ability to sense lipopolysaccharides, as is the case for BPI and LBP, or in lipid exchange between lipoprotein particles, as is the case for CETP and PLTP. The Takeout-like proteins, which are comprised of insect juvenile hormone-binding proteins and arthropod allergens, transport, where known, lipid hormones to target tissues during insect development. In all cases, the activity of these proteins is underpinned by their ability to bind large, hydrophobic ligands in their central cavity and segregate them away from the aqueous environment. Furthermore, where they are involved in lipid exchange, recent structural studies have highlighted their ability to establish lipophilic, tubular channels, either between organelles in the case of SMP domains or between lipoprotein particles in the case of CETP. Here, we review the current knowledge on the structure, versatile functions, and evolution of the TULIP superfamily. We propose a deep evolutionary split in this superfamily, predating the Last Eukaryotic Common Ancestor, between the SMP-like proteins, which act on

  1. Characterization of the Lateral Distribution of Fluorescent Lipid in Binary-Constituent Lipid Monolayers by Principal Component Analysis

    Directory of Open Access Journals (Sweden)

    István P. Sugár

    2010-01-01

    Full Text Available Lipid lateral organization in binary-constituent monolayers consisting of fluorescent and nonfluorescent lipids has been investigated by acquiring multiple emission spectra during measurement of each force-area isotherm. The emission spectra reflect BODIPY-labeled lipid surface concentration and lateral mixing with different nonfluorescent lipid species. Using principal component analysis (PCA each spectrum could be approximated as the linear combination of only two principal vectors. One point on a plane could be associated with each spectrum, where the coordinates of the point are the coefficients of the linear combination. Points belonging to the same lipid constituents and experimental conditions form a curve on the plane, where each point belongs to a different mole fraction. The location and shape of the curve reflects the lateral organization of the fluorescent lipid mixed with a specific nonfluorescent lipid. The method provides massive data compression that preserves and emphasizes key information pertaining to lipid distribution in different lipid monolayer phases. Collectively, the capacity of PCA for handling large spectral data sets, the nanoscale resolution afforded by the fluorescence signal, and the inherent versatility of monolayers for characterization of lipid lateral interactions enable significantly enhanced resolution of lipid lateral organizational changes induced by different lipid compositions.

  2. Lipid peroxidation, detoxification capacity, and genome damage in mice after transplacental exposure to pharmaceutical drugs

    Directory of Open Access Journals (Sweden)

    D. Markovic

    2013-12-01

    Full Text Available Data on genome damage, lipid peroxidation, and levels of glutathione peroxidase (GPX in newborns after transplacental exposure to xenobiotics are rare and insufficient for risk assessment. The aim of the current study was to analyze, in an animal model, transplacental genotoxicity, lipid peroxidation, and detoxification disturbances caused by the following drugs commonly prescribed to pregnant women: paracetamol, fluconazole, 5-nitrofurantoin, and sodium valproate. Genome damage in dams and their newborn pups transplacentally exposed to these drugs was investigated using the in vivo micronucleus (MN assay. The drugs were administered to dams intraperitoneally in three consecutive daily doses between days 12 and 14 of pregnancy. The results were correlated, with detoxification capacity of the newborn pups measured by the levels of GPX in blood and lipid peroxidation in liver measured by malondialdehyde (HPLC-MDA levels. Sodium valproate and 5-nitrofurantoin significantly increased MN frequency in pregnant dams. A significant increase in the MN frequency of newborn pups was detected for all drugs tested. This paper also provides reference levels of MDA in newborn pups, according to which all drugs tested significantly lowered MDA levels of newborn pups, while blood GPX activity dropped significantly only after exposure to paracetamol. The GPX reduction reflected systemic oxidative stress, which is known to occur with paracetamol treatment. The reduction of MDA in the liver is suggested to be an unspecific metabolic reaction to the drugs that express cytotoxic, in particular hepatotoxic, effects associated with oxidative stress and lipid peroxidation.

  3. The Flexibility of Ectopic Lipids

    Directory of Open Access Journals (Sweden)

    Hannah Loher

    2016-09-01

    Full Text Available In addition to the subcutaneous and the visceral fat tissue, lipids can also be stored in non-adipose tissue such as in hepatocytes (intrahepatocellular lipids; IHCL, skeletal (intramyocellular lipids; IMCL or cardiac muscle cells (intracardiomyocellular lipids; ICCL. Ectopic lipids are flexible fuel stores that can be depleted by physical exercise and repleted by diet. They are related to obesity and insulin resistance. Quantification of IMCL was initially performed invasively, using muscle biopsies with biochemical and/or histological analysis. 1H-magnetic resonance spectroscopy (1H-MRS is now a validated method that allows for not only quantifying IMCL non-invasively and repeatedly, but also assessing IHCL and ICCL. This review summarizes the current available knowledge on the flexibility of ectopic lipids. The available evidence suggests a complex interplay between quantitative and qualitative diet, fat availability (fat mass, insulin action, and physical exercise, all important factors that influence the flexibility of ectopic lipids. Furthermore, the time frame of the intervention on these parameters (short-term vs. long-term appears to be critical. Consequently, standardization of physical activity and diet are critical when assessing ectopic lipids in predefined clinical situations.

  4. Lipid nanocarriers (GeluPearl) containing amphiphilic lipid Gelucire 50/13 as a novel stabilizer: fabrication, characterization and evaluation for oral drug delivery

    International Nuclear Information System (INIS)

    Date, Abhijit A; Nagarsenker, Mangal S; Vador, Nimish; Jagtap, Aarti

    2011-01-01

    Purpose. To evaluate the ability of Gelucire 50/13 (an amphiphilic lipid excipient) to act as a stabilizer for lipid nanocarriers such as solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) and to establish the ability of Gelucire 50/13 based lipid nanocarriers to improve oral delivery of hydrophobic drugs using repaglinide (RPG) as a model drug. Methods. The ability of Gelucire 50/13 to nanosize various solid lipids was evaluated. The ability of Gelucire 50/13 to yield NLC was evaluated by using Precirol ATO 5 as a model solid lipid and various liquid lipids (oils). Gelucire 50/13 based NLC (GeluPearl) were evaluated for their ability to improve the efficacy of RPG on oral administration in comparison to RPG tablets. The short term stability of RPG-GeluPearl was evaluated at 25 deg. C/60% RH. Results. Gelucire 50/13 could successfully yield SLN and NLC of various solid lipids, demonstrating its potential to act as a novel stabilizer. DSC studies indicated that Gelucire 50/13 interacts with Precirol ATO 5 and this interaction suppresses polymorphic transitions of both the components. RPG-GeluPearl exhibited significantly higher anti-diabetic activity compared to marketed RPG tablets. RPG-GeluPearl demonstrated good colloidal and chemical stability at the end of 1 month.

  5. Activity of a lipid synthesis inhibitor (spiromesifen in Culiseta longiareolata (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Hayette Bouabida

    2017-12-01

    Full Text Available Objective: To evaluate the activity of spiromesifen against the most abundant and investigated mosquito species, Culiseta longiareolata Aitken, 1954 (Diptera, Culicidae. Methods: Culiseta longiareolata larvae were collected from untreated areas located at Tébessa (Northeast Algeria. A commercial formulation of spiromesifen (Oberon® 240 SC was tested at different concentrations ranging between 238 and 1428 μg/L on newly molted fourth-instar larvae under standard laboratory conditions according to Word Health Organization recommendations. The effects were examined on the mortality, the morphometric measurements, two biomarkers (catalase and malondialdehyde, and the biochemical composition of larvae, respectively. Results: The compound exhibited insecticidal activity. Moreover, it disturbed growth and several morphological aberrations were observed. It also affected body volume, biomarkers and contents of carbohydrates, lipids and proteins. A marked effect on lipids and malondialdehyde was noted, confirming its primary mode of action on lipid synthesis. Conclusions: Spiromesifen appears less potent than other insecticides tested such as the insect growth disruptors. Keywords: Culiseta longiareolata, Spiromesifen, Toxicity, Biochemical composition, Biomarkers

  6. Use of isothermal titration calorimetry to study the interaction of short-chain alcohols with lipid membranes

    DEFF Research Database (Denmark)

    Trandum, Christa; Westh-Andersen, Peter; Jørgensen, Kent

    1999-01-01

    of short-chain alcohols on Lipid bilayers. isothermal titration calorimetry (ITC) has been used to determine the energy involved in the association of the alcohols with lipid bilayers. Pure unilamellar DMPC liposomes and DMPC liposomes incorporated with different amounts of cholesterol, sphingomyelin...... dependent on the lipid bilayer composition. In the presence of high concentrations of cholesterol, the binding enthalpy of ethanol is decreased, whereas the presence of ceramides enhances the enthalpic response of the lipid bilayer to ethanol. Isothermal titration calorimetry offers a new methodology...

  7. Arabidopsis lipid droplet-associated protein (LDAP)–interacting protein (LDIP) influences lipid droplet size and neutral lipid homeostasis in both leaves and seeds

    Science.gov (United States)

    Cytoplasmic lipid droplets (LDs) are found in all types of plant cells where they are derived from the endoplasmic reticulum and function as a repository for neutral lipids, as well as serving in lipid remodelling and signalling. However, the mechanisms underlying the formation and functioning of pl...

  8. Lipids and Fatty Acids in Algae: Extraction, Fractionation into Lipid Classes, and Analysis by Gas Chromatography Coupled with Flame Ionization Detector (GC-FID).

    Science.gov (United States)

    Guihéneuf, Freddy; Schmid, Matthias; Stengel, Dagmar B

    2015-01-01

    Despite the number of biochemical studies exploring algal lipids and fatty acid biosynthesis pathways and profiles, analytical methods used by phycologists for this purpose are often diverse and incompletely described. Potential confusion and potential variability of the results between studies can therefore occur due to change of protocols for lipid extraction and fractionation, as well as fatty acid methyl esters (FAME) preparation before gas chromatography (GC) analyses. Here, we describe a step-by-step procedure for the profiling of neutral and polar lipids using techniques such as solid-liquid extraction (SLE), thin-layer chromatography (TLC), and gas chromatography coupled with flame ionization detector (GC-FID). As an example, in this protocol chapter, analyses of neutral and polar lipids from the marine microalga Pavlova lutheri (an EPA/DHA-rich haptophyte) will be outlined to describe the distribution of fatty acid residues within its major lipid classes. This method has been proven to be a reliable technique to assess changes in lipid and fatty acid profiles in several other microalgal species and seaweeds.

  9. Investigation of Lipid Oxidation in the Raw Materials of a Topical Skin Formulation: A Topical Skin Formulation Containing a High Lipid Content

    DEFF Research Database (Denmark)

    Thomsen, Birgitte Raagaard; Taylor, Richard; Madsen, Robert

    2018-01-01

    Several studies have demonstrated that lipid oxidation often occurs in topical skin formulations which can affect product odor (both positively and negatively). Furthermore, odor detection threshold values and odor descriptors of identified volatile oxidation products in cleansing and skin cream...... formulation prototypes were recently determined by a trained sensory panel at the Technical University of Denmark in the Division of Food Technology. In this study, we investigated lipid oxidation in a prototype skin cream formulation as well as in selected cosmetic skin care raw materials. Lipid oxidation...... was also identified. In addition, the concentrations of several well-known lipid oxidation products increased during storage and were suggested to originate primarily from rice bran wax, which oxidized more readily than other raw materials due to its unsaturated nature....

  10. Intravenous Lipid Emulsion as an Antidote for the Treatment of Acute Poisoning: A Bibliometric Analysis of Human and Animal Studies.

    Science.gov (United States)

    Zyoud, Sa'ed H; Waring, W Stephen; Al-Jabi, Samah W; Sweileh, Waleed M; Rahhal, Belal; Awang, Rahmat

    2016-11-01

    In recent years, there has been increasing interest in the role of intravenous lipid formulations as potential antidotes in patients with severe cardiotoxicity caused by drug toxicity. The aim of this study was to conduct a comprehensive bibliometric analysis of all human and animal studies featuring lipid emulsion as an antidote for the treatment of acute poisoning. The Scopus database search was performed on 5 February 2016 to analyse the research output related to intravenous lipid emulsion as an antidote for the treatment of acute poisoning. Research indicators used for analysis included total number of articles, date (year) of publication, total citations, value of the h-index, document types, countries of publication, journal names, collaboration patterns and institutions. A total of 594 articles were retrieved from Scopus database for the period of 1955-2015. The percentage share of global intravenous lipid emulsion research output showed that research output was 85.86% in 2006-2015 with yearly average growth in this field of 51 articles per year. The USA, United Kingdom (UK), France, Canada, New Zealand, Germany, Australia, China, Turkey and Japan accounted for 449 (75.6%) of all the publications. The total number of citations for all documents was 9,333, with an average of 15.7 citations per document. The h-index of the retrieved documents for lipid emulsion research as antidote for the treatment of acute poisoning was 49. The USA and the UK achieved the highest h-indices, 34 and 14, respectively. New Zealand produced the greatest number of documents with international collaboration (51.9%) followed by Australia (50%) and Canada (41.4%) out of the total number of publications for each country. In summary, we found an increase in the number of publications in the field of lipid emulsion after 2006. The results of this study demonstrate that the majority of publications in the field of lipid emulsion were published by high-income countries. Researchers from

  11. Lipids and skin barrier function - a clinical perspective

    DEFF Research Database (Denmark)

    Jungersted, J.M.; Hellgren, Lars; Jemec, G.B.E.

    2008-01-01

    The stratum corneum (SC) protects us from dehydration and external dangers. Much is known about the morphology of the SC and penetration of drugs through it, but the data are mainly derived from in vitro and animal experiments. In contrast, only a few studies have the human SC lipids as their focus...... and in particular, the role of barrier function in the pathogenesis of skin disease and its subsequent treatment protocols. The 3 major lipids in the SC of importance are ceramides, free fatty acids, and cholesterol. Human studies comparing levels of the major SC lipids in patients with atopic dermatitis...

  12. Lipid biomarkers for bacterial ecosystems: studies of cultured organisms, hydrothermal environments and ancient sediments

    Science.gov (United States)

    Summons, R. E.; Jahnke, L. L.; Simoneit, B. R.

    1996-01-01

    This paper forms part of our long-term goal of using molecular structure and carbon isotopic signals preserved as hydrocarbons in ancient sediments to improve understanding of the early evolution of Earth's surface environment. We are particularly concerned with biomarkers which are informative about aerobiosis. Here, we combine bacterial biochemistry with the organic geochemistry of contemporary and ancient hydrothermal ecosystems to construct models for the nature, behaviour and preservation potential of primitive microbial communities. We use a combined molecular and isotopic approach to characterize lipids produced by cultured bacteria and test a variety of culture conditions which affect their biosynthesis. This information is then compared with lipid mixtures isolated from contemporary hot springs and evaluated for the kinds of chemical change that would accompany burial and incorporation into the sedimentary record. In this study we have shown that growth temperature does not appear to alter isotopic fractionation within the lipid classes produced by a methanotropic bacterium. We also found that cultured cyanobacteria biosynthesize diagnostic methylalkanes and dimethylalkanes with the latter only made when growing under low pCO2. In an examination of a microbial mat sample from Octopus Spring, Yellowstone National Park (USA), we could readily identify chemical structures with 13C contents which were diagnostic for the phototrophic organisms such as cyanobacteria and Chloroflexus. We could not, however, find molecular evidence for operation of a methane cycle in the particular mat samples we studied.

  13. Lipid Metabolism, Apoptosis and Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Chunfa Huang

    2015-01-01

    Full Text Available Lipid metabolism is regulated by multiple signaling pathways, and generates a variety of bioactive lipid molecules. These bioactive lipid molecules known as signaling molecules, such as fatty acid, eicosanoids, diacylglycerol, phosphatidic acid, lysophophatidic acid, ceramide, sphingosine, sphingosine-1-phosphate, phosphatidylinositol-3 phosphate, and cholesterol, are involved in the activation or regulation of different signaling pathways. Lipid metabolism participates in the regulation of many cellular processes such as cell growth, proliferation, differentiation, survival, apoptosis, inflammation, motility, membrane homeostasis, chemotherapy response, and drug resistance. Bioactive lipid molecules promote apoptosis via the intrinsic pathway by modulating mitochondrial membrane permeability and activating different enzymes including caspases. In this review, we discuss recent data in the fields of lipid metabolism, lipid-mediated apoptosis, and cancer therapy. In conclusion, understanding the underlying molecular mechanism of lipid metabolism and the function of different lipid molecules could provide the basis for cancer cell death rationale, discover novel and potential targets, and develop new anticancer drugs for cancer therapy.

  14. Lipid vesicle-mediated affinity chromatography using magnetic activated cell sorting (LIMACS): a novel method to analyze protein-lipid interaction.

    Science.gov (United States)

    Bieberich, Erhard

    2011-04-26

    The analysis of lipid protein interaction is difficult because lipids are embedded in cell membranes and therefore, inaccessible to most purification procedures. As an alternative, lipids can be coated on flat surfaces as used for lipid ELISA and Plasmon resonance spectroscopy. However, surface coating lipids do not form microdomain structures, which may be important for the lipid binding properties. Further, these methods do not allow for the purification of larger amounts of proteins binding to their target lipids. To overcome these limitations of testing lipid protein interaction and to purify lipid binding proteins we developed a novel method termed lipid vesicle-mediated affinity chromatography using magnetic-activated cell sorting (LIMACS). In this method, lipid vesicles are prepared with the target lipid and phosphatidylserine as the anchor lipid for Annexin V MACS. Phosphatidylserine is a ubiquitous cell membrane phospholipid that shows high affinity to the protein Annexin V. Using magnetic beads conjugated to Annexin V the phosphatidylserine-containing lipid vesicles will bind to the magnetic beads. When the lipid vesicles are incubated with a cell lysate the protein binding to the target lipid will also be bound to the beads and can be co-purified using MACS. This method can also be used to test if recombinant proteins reconstitute a protein complex binding to the target lipid. We have used this method to show the interaction of atypical PKC (aPKC) with the sphingolipid ceramide and to co-purify prostate apoptosis response 4 (PAR-4), a protein binding to ceramide-associated aPKC. We have also used this method for the reconstitution of a ceramide-associated complex of recombinant aPKC with the cell polarity-related proteins Par6 and Cdc42. Since lipid vesicles can be prepared with a variety of sphingo- or phospholipids, LIMACS offers a versatile test for lipid-protein interaction in a lipid environment that resembles closely that of the cell membrane

  15. Lipid structure does not modify incorporation of EPA and DHA into blood lipids in healthy adults: a randomised-controlled trial.

    Science.gov (United States)

    West, Annette L; Burdge, Graham C; Calder, Philip C

    2016-09-01

    Dietary supplementation is an effective means to improve EPA and DHA status. However, it is unclear whether lipid structure affects EPA+DHA bioavailability. We determined the effect of consuming different EPA and DHA lipid structures on their concentrations in blood during the postprandial period and during dietary supplementation compared with unmodified fish oil TAG (uTAG). In a postprandial cross-over study, healthy men (n 9) consumed in random order test meals containing 1·1 g EPA+0·37 g DHA as either uTAG, re-esterified TAG, free fatty acids (FFA) or ethyl esters (EE). In a parallel design supplementation study, healthy men and women (n 10/sex per supplement) consumed one supplement type for 12 weeks. Fatty acid composition was determined by GC. EPA incorporation over 6 h into TAG or phosphatidylcholine (PC) did not differ between lipid structures. EPA enrichment in NEFA was lower from EE than from uTAG (P=0·01). Plasma TAG, PC or NEFA DHA incorporation did not differ between lipid structures. Lipid structure did not affect TAG or NEFA EPA incorporation and PC or NEFA DHA incorporation following dietary supplementation. Plasma TAG peak DHA incorporation was greater (P=0·02) and time to peak shorter (P=0·02) from FFA than from uTAG in men. In both studies, the order of EPA and DHA incorporation was PC>TAG>NEFA. In conclusion, EPA and DHA lipid structure may not be an important consideration in dietary interventions.

  16. Myocardial lipid content in Fabry disease: a combined 1H-MR spectroscopy and MR imaging study at 3 Tesla.

    Science.gov (United States)

    Petritsch, B; Köstler, H; Weng, A M; Horn, M; Gassenmaier, T; Kunz, A S; Weidemann, F; Wanner, C; Bley, T A; Beer, M

    2016-10-28

    Fabry disease is characterized by a progressive deposition of sphingolipids in different organ systems, whereby cardiac involvement leads to death. We hypothesize that lysosomal storage of sphingolipids in the heart as occurring in Fabry disease does not reflect in higher cardiac lipid concentrations detectable by 1 H magnetic resonance spectroscopy (MRS) at 3 Tesla. Myocardial lipid content was quantified in vivo by 1 H-MRS in 30 patients (12 male, 18 female; 18 patients treated with enzyme replacement therapy) with genetically proven Fabry disease and in 30 healthy controls. The study protocol combined 1 H-MRS with cardiac cine imaging and LGE MRI in a single examination. Myocardial lipid content was not significantly elevated in Fabry disease (p = 0.225). Left ventricular (LV) mass was significantly higher in patients suffering from Fabry disease compared to controls (p = 0.019). Comparison of patients without signs of myocardial fibrosis in MRI (LGE negative; n = 12) to patients with signs of fibrosis (LGE positive; n = 18) revealed similar myocardial lipid content in both groups (p > 0.05), while the latter showed a trend towards elevated LV mass (p = 0.076). This study demonstrates the potential of lipid metabolic investigation embedded in a comprehensive examination of cardiac morphology and function in Fabry disease. There was no evidence that lysosomal storage of sphingolipids influences cardiac lipid content as measured by 1 H-MRS. Finally, the authors share the opinion that a comprehensive cardiac examination including three subsections (LGE; 1 H-MRS; T 1 mapping), could hold the highest potential for the final assessment of early and late myocardial changes in Fabry disease.

  17. Concurrent production of carotenoids and lipid by a filamentous microalga Trentepohlia arborum.

    Science.gov (United States)

    Chen, Lin; Zhang, Lanlan; Liu, Tianzhong

    2016-08-01

    During the study of Trentepohlia arborum it became clear that its cells are rich in lipids and carotenoids. Thus, lipid content, composition and fatty acids profiles in individual lipid classes, as well as pigment profiles, responding to different culture conditions, were further investigated. The results showed that the predominant carotenoids and lipid fraction in total lipid in this study was β-carotene and TAG, respectively. The lipid content increased significantly under high light while nitrogen-replete conditions induced the highest carotenoids content. However, only with a double stress of high light and nitrogen-deficiency it was possible to maximize the productivities of both carotenoids and lipids. Carotenoids (mainly β-carotene) accounted for ca. 5% of the microalgal lipid under the double stress. Data herein show the potential of T. arborum for the production of both lipids and carotenoids, and hence provide an appropriate way to produce different products from T. arborum. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Cholesterol effect on water permeability through DPPC and PSM lipid bilayers: a molecular dynamics study.

    Science.gov (United States)

    Saito, Hiroaki; Shinoda, Wataru

    2011-12-29

    Water permeability of two different lipid bilayers of dipalmitoylphosphatidylcholine (DPPC) and palmitoylsphingomyelin (PSM) in the absence and presence of cholesterol (0-50 mol %) have been studied by molecular dynamics simulations to elucidate the molecular mechanism of the reduction in water leakage across the membranes by the addition of cholesterol. An enhanced free energy barrier was observed in these membranes with increased cholesterol concentration, and this was explained by the reduced cavity density around the cholesterol in the hydrophobic membrane core. There was an increase of trans conformers in the hydrophobic lipid chains adjacent to the cholesterol, which reduced the cavity density. The enhanced free energy barrier was found to be the main reason to reduce the water permeability with increased cholesterol concentration. At low cholesterol concentrations the PSM bilayer exhibited a higher free energy barrier than the DPPC bilayer for water permeation, while at greater than 30 mol % of cholesterol the difference became minor. This tendency for the PSM and DPPC bilayers to resemble each other at higher cholesterol concentrations was similar to commonly observed trends in several structural properties, such as order parameters, cross-sectional area per molecule, and cavity density profiles in the hydrophobic regions of bilayer membranes. These results demonstrate that DPPC and PSM bilayers with high cholesterol contents possess similar physical properties, which suggests that the solubility of cholesterol in these lipid bilayers has importance for an understanding of multicomponent lipid membranes with cholesterol. © 2011 American Chemical Society

  19. Vegan diet and blood lipid profiles: a cross-sectional study of pre and postmenopausal women.

    Science.gov (United States)

    Huang, Yee-Wen; Jian, Zhi-Hong; Chang, Hui-Chin; Nfor, Oswald Ndi; Ko, Pei-Chieh; Lung, Chia-Chi; Lin, Long-Yau; Ho, Chien-Chang; Chiang, Yi-Chen; Liaw, Yung-Po

    2014-04-08

    Vegan diet has been associated with lower risk of cardiovascular diseases and mortality, partly due to its effects on serum lipid profiles. Lipid profiles [high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C) and triglycerides (TG)] have not been fully elucidated either in pre and postmenopausal vegans or in ovo-lacto vegetarians. This study aimed to compare lipid profiles among vegans, ovo-lacto vegetarians and omnivores. Demographic data and lipid profiles were obtained from the 2002 Taiwanese Survey on Hypertension, Hyperglycemia and Hyperlipidemia. Multivariate linear regression analysis was used to examine factors significantly and independently associated with different categories of veganism and to estimate the β value of lipid profiles in the dietary types. A total of 2397 premenopausal and 1154 postmenopausal participants who did not receive lipid lowering drugs were enrolled. Premenopausal vegans had significantly lower HDL-C and higher TG, LDL-C/HDL-C, total cholesterol (TC)/HDL-C and TG/HDL-C compared with omnivores. For postmenopausal women, vegans had lower TC while ovo-lacto vegetarians were observed with low HDL-C when compared with omnivores. Multivariate linear regression analyses showed that vegan and ovo-lacto vegetarian diets decreased HDL-C levels in premenopausal women (β = -7.63, p = 0.001 and β = -4.87, p = 0.001, respectively). There were significant associations between lower LDL-C and ovo-lacto vegetarian diets (β = -7.14, p = 0.008) and also between TG and vegan diet (β = 23.37, p = 0.008), compared with omnivorous diet. Post-menopausal women reported to have consumed either a vegan or an ovo-lacto vegetarian diet were at the risk of having low HDL-C unlike those that consumed omnivorous diets (β = -4.88, p = 0.015 and β = -4.48, p = 0.047). There were no significant changes in LDL-C in both pre and postmenopausal vegans. Vegan diet was

  20. Prevention of cardiovascular disease based on lipid lowering treatment: a challenge for the Mexican health system.

    Science.gov (United States)

    Gómez-Pérez, Francisco J; Rojas, Rosalba; Villalpando, Salvador; Barquera, Simón; Rull, Juan; Aguilar-Salinas, Carlos A

    2010-01-01

    To estimate the percentage of Mexican adults that may require lipid-lowering treatment according to National Cholesterol Education Program-III guidelines, using data from the National Health and Nutrition Survey 2006 (ENSANut 2006). Information was obtained from 4 040 subjects aged 20 to 69 years, studied after a 9 to 12 hours fast. A cardiovascular risk equivalent was found in 13.8% and >or=2 risk factors were present in 31.5% of the population. LDL-C concentrations were above the treatment goal in 70% of the high-risk group and in 38.6% of subjects with >or=2 risk factors. Nearly 12 million Mexicans should be taught how to change their lifestyles and close to 8 million individuals require drug therapy to decrease their cardiovascular risk. Thirty percent of Mexican adults require some form of lipid-lowering treatment (lifestyle modifications in 36.25%, drug therapy in 24.19%).

  1. Lipid Nanotechnology

    Directory of Open Access Journals (Sweden)

    Gijsje Koenderink

    2013-02-01

    Full Text Available Nanotechnology is a multidisciplinary field that covers a vast and diverse array of devices and machines derived from engineering, physics, materials science, chemistry and biology. These devices have found applications in biomedical sciences, such as targeted drug delivery, bio-imaging, sensing and diagnosis of pathologies at early stages. In these applications, nano-devices typically interface with the plasma membrane of cells. On the other hand, naturally occurring nanostructures in biology have been a source of inspiration for new nanotechnological designs and hybrid nanostructures made of biological and non-biological, organic and inorganic building blocks. Lipids, with their amphiphilicity, diversity of head and tail chemistry, and antifouling properties that block nonspecific binding to lipid-coated surfaces, provide a powerful toolbox for nanotechnology. This review discusses the progress in the emerging field of lipid nanotechnology.

  2. Nitrogen-deprivation elevates lipid levels in Symbiodinium spp. by lipid droplet accumulation: morphological and compositional analyses.

    Directory of Open Access Journals (Sweden)

    Pei-Luen Jiang

    Full Text Available Stable cnidarian-dinoflagellate (genus Symbiodinium endosymbioses depend on the regulation of nutrient transport between Symbiodinium populations and their hosts. It has been previously shown that the host cytosol is a nitrogen-deficient environment for the intracellular Symbiodinium and may act to limit growth rates of symbionts during the symbiotic association. This study aimed to investigate the cell proliferation, as well as ultrastructural and lipid compositional changes, in free-living Symbiodinium spp. (clade B upon nitrogen (N-deprivation. The cell proliferation of the N-deprived cells decreased significantly. Furthermore, staining with a fluorescent probe, boron dipyrromethane 493/503 (BODIPY 493/503, indicated that lipid contents progressively accumulated in the N-deprived cells. Lipid analyses further showed that both triacylglycerol (TAG and cholesterol ester (CE were drastically enriched, with polyunsaturated fatty acids (PUFA; i.e., docosahexaenoic acid, heneicosapentaenoic acid, and oleic acid became more abundant. Ultrastructural examinations showed that the increase in concentration of these lipid species was due to the accumulation of lipid droplets (LDs, a cellular feature that have previously shown to be pivotal in the maintenance of intact endosymbioses. Integrity of these stable LDs was maintained via electronegative repulsion and steric hindrance possibly provided by their surface proteins. Proteomic analyses of these LDs identified proteins putatively involved in lipid metabolism, signaling, stress response and energy metabolism. These results suggest that LDs production may be an adaptive response that enables Symbiodinium to maintain sufficient cellular energy stores for survival under the N-deprived conditions in the host cytoplasm.

  3. Extraction of microalgal lipids and the influence of polar lipids on biodiesel production by lipase-catalyzed transesterification.

    Science.gov (United States)

    Navarro López, Elvira; Robles Medina, Alfonso; González Moreno, Pedro Antonio; Esteban Cerdán, Luis; Molina Grima, Emilio

    2016-09-01

    In order to obtain microalgal saponifiable lipids (SLs) fractions containing different polar lipid (glycolipids and phospholipids) contents, SLs were extracted from wet Nannochloropsis gaditana microalgal biomass using seven extraction systems, and the polar lipid contents of some fractions were reduced by low temperature acetone crystallization. We observed that the polar lipid content in the extracted lipids depended on the polarity of the first solvent used in the extraction system. Lipid fractions with polar lipid contents between 75.1% and 15.3% were obtained. Some of these fractions were transformed into fatty acid methyl esters (FAMEs, biodiesel) by methanolysis, catalyzed by the lipases Novozym 435 and Rhizopus oryzae in tert-butanol medium. We observed that the reaction velocity was higher the lower the polar lipid content, and that the final FAME conversions achieved after using the same lipase batch to catalyze consecutive reactions decreased in relation to an increase in the polar lipid content. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. The lipid accumulation product as a useful index for identifying abnormal glucose regulation in young Korean women.

    Science.gov (United States)

    Oh, J-Y; Sung, Y-A; Lee, H J

    2013-04-01

    The lipid accumulation product, a combination of waist circumference and triglycerides concentration, has been suggested as a better marker for abnormal glucose regulation than BMI. We aimed to compare the lipid accumulation product and BMI as useful markers for abnormal glucose regulation in young Korean women. The lipid accumulation product was calculated using the formula [waist circumference (cm) - 58] × triglycerides (mmol/l). Glucose tolerance status was determined using a 75-g oral glucose tolerance test in 2810 Korean women aged 18-39 years from the general population. The prevalence of abnormal glucose regulation was 6.8% (isolated impaired fasting glucose 1.8%, isolated impaired glucose tolerance 4.0%; impaired fasting glucose + impaired glucose tolerance 0.4% and diabetes mellitus 0.6%). According to the quintile distributions of the lipid accumulation product and BMI, women with a lipid accumulation product quintile greater than their BMI quintile exhibited significantly greater areas under the curve and higher levels of 2-h post-load glucose, insulin, homeostasis model analysis of insulin resistance and lipid profiles than did women with a BMI quintile greater than their lipid accumulation product quintile. Multiple logistic regression revealed that the lipid accumulation product exhibited a higher odds ratio for abnormal glucose regulation than did BMI after adjusting for age, systolic blood pressure, HDL cholesterol, previous history of gestational diabetes and family history of diabetes (odds ratios 3.5 and 2.6 of the highest vs. the lowest quintiles of lipid accumulation product and BMI, respectively). The lipid accumulation product could be useful for identifying the young Korean women with abnormal glucose regulation. © 2012 The Authors. Diabetic Medicine © 2012 Diabetes UK.

  5. Role of lipid peroxidation in pathogenesis of senile cataract

    Directory of Open Access Journals (Sweden)

    Kisić Bojana

    2009-01-01

    Full Text Available Background /Aim. Cataract is a structural, biochemical and optical change in the eye lens, which changes transmission and refraction of light rays reducing keenness and clarity of a figure on the retina. Its occurrence is highest in older people, over the age of 65 (45.9%, thus a certain degree of opacification exists practically in all people over the 70. Our research was directed to measuring of lipid peroxidation products in cataract lenses involved in early stages of cataractogenesis through oxidative stress and in the development of mature cataract. Methods. Clinical and biochemical research was carried out in 101 patients with cataract, 46 women and 55 men. The average age of the group was 72.47 (ґ = 7.98. According to the cataract maturity degree the patients were classified into two groups as follows: cataracta senilis incipiens (n = 41 and cataracta senilis matura (n = 60. Measuring of diene conjugates was carried out by spectrophotometer. Fluorescent lipid peroxidation products were measured by a spectrofluorophotometer, and malondialdehyde (MDA concentration was measured by colorimeter as a product of a reaction with thiobarbituric acid (TBA. Result. Significantly higher diene conjugated concentration in lenses was measured in the patients with the diagnosis cataracta senilis incipiens (p < 0.001 as well as the intensity of fluorescent iminopropens (p < 0.001. Significantly higher MDA concentration in lens (p < 0.001 was measured in the patients with cataracta senilis matura. Conclusion. The lens structure changes caused by lipid peroxidation can, with other risk factors present, influence the occurrence and development of mature cataract. Some cataract types show different lipid peroxidation intensity with the most distinct changes in cataract which started as corticonuclear.

  6. The impact of lipid composition on the stability of the tear fluid lipid layer

    DEFF Research Database (Denmark)

    Kulovesi, P.; Telenius, J.; Koivuniemi, A.

    2012-01-01

    The tear fluid protects the corneal epithelium from drying and pathogens and it also provides nutrients to these cells. Tear fluid is composed of an aqueous layer as well as a lipid layer that resides at the air-tear interface. The function of the lipid layer is to lower the surface tension of th......-neutral lipid ratio. The results provide a plausible rationale for the development of dry eye syndrome in blepharitis patients.......The tear fluid protects the corneal epithelium from drying and pathogens and it also provides nutrients to these cells. Tear fluid is composed of an aqueous layer as well as a lipid layer that resides at the air-tear interface. The function of the lipid layer is to lower the surface tension...

  7. DNA release from lipoplexes by anionic lipids: correlation with lipid mesomorphism, interfacial curvature, and membrane fusion

    Energy Technology Data Exchange (ETDEWEB)

    Tarahovsky, Yury S.; Koynova, Rumiana; MacDonald, Robert C. (Northwestern)

    2010-01-18

    DNA release from lipoplexes is an essential step during lipofection and is probably a result of charge neutralization by cellular anionic lipids. As a model system to test this possibility, fluorescence resonance energy transfer between DNA and lipid covalently labeled with Cy3 and BODIPY, respectively, was used to monitor the release of DNA from lipid surfaces induced by anionic liposomes. The separation of DNA from lipid measured this way was considerably slower and less complete than that estimated with noncovalently labeled DNA, and depends on the lipid composition of both lipoplexes and anionic liposomes. This result was confirmed by centrifugal separation of released DNA and lipid. X-ray diffraction revealed a clear correlation of the DNA release capacity of the anionic lipids with the interfacial curvature of the mesomorphic structures developed when the anionic and cationic liposomes were mixed. DNA release also correlated with the rate of fusion of anionic liposomes with lipoplexes. It is concluded that the tendency to fuse and the phase preference of the mixed lipid membranes are key factors for the rate and extent of DNA release. The approach presented emphasizes the importance of the lipid composition of both lipoplexes and target membranes and suggests optimal transfection may be obtained by tailoring lipoplex composition to the lipid composition of target cells.

  8. Nitric Oxide, Inflammation, Lipid Profile, and Cortisol in Normal- and Overweight Women With Fibromyalgia.

    Science.gov (United States)

    Rus, Alma; Molina, Francisco; Gassó, Manuela; Camacho, Maria Victoria; Peinado, Maria Ángeles; del Moral, Maria Luisa

    2016-03-01

    Research has identified many factors associated with fibromyalgia (FM), but findings have been inconsistent. This study aimed to investigate changes in levels of nitric oxide (NO), inflammatory markers, lipid profile, and cortisol in normal- and overweight patients with FM and controls. Since most patients with FM are overweight, we explored possible changes in these markers according to body mass index (BMI). This preliminary study was performed on serum samples of women with FM and age-matched controls, grouped according to their BMI: 12 normal-weight patients and 12 controls and 13 overweight patients and 8 controls. Ozone-based chemiluminescence assay was used to measure NO. Inflammatory mediators and cortisol were determined by immunoassay. Lipid profile was measured by a spectrophotometric procedure. Functional capacity was assessed by the fibromyalgia impact questionnaire (FIQ). Normal-weight patients showed higher levels of C-reactive protein (CRP) and apolipoprotein B compared to controls (both p < .05). CRP, apolipoprotein B, and triglycerides were higher in overweight patients versus overweight controls (all p < .05) and in overweight versus normal-weight patients (CRP p < .01; apolipoprotein B, triglycerides p < .05). The other markers were unaffected. Apolipoprotein B (r = .762; p < .05) and NO (r = -.921; p < .05) levels correlated with FIQ score in normal-weight patients. CRP level correlated with FIQ (r = .912; p < .05) in overweight patients. CRP and apolipoprotein B, biomarkers linked to cardiovascular events, may be associated with FM-related dysfunction in normal- and overweight women with FM. Their increased levels in these patients may indicate an increased risk of cardiovascular disease. © The Author(s) 2015.

  9. Ultrastructural and flow cytometric analyses of lipid accumulation in microalgae

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, J.A.; Hand, R.E. Jr.; Mann, R.C.

    1986-12-01

    Lipid accumulation in three species of microalgae was investigated with flow cytometry (FCM) and transmission electron microscopy (TEM). Previous studies using batch cultures of a algae have led to the assumption that lipid accumulation in microalgae is a gradual process requiring at least several days for completion. However, FCM reveals, through changes in the chlorophyll:lipid ratio, that the time span required for individual cells to change metabolic state is short. Simultaneous FCM measurements of chlorophyll and nile red (neutral lipid) fluorescence in individual cells of nitrogen-deficient Isochrysis populations revealed a bimodal population distribution as one stage in the lipid accumulation process. The fact that two discrete populations exist, with few cells in an intermediate stage, suggests rapid response to a liqid trigger. Interpretations of light and electron microscopic observations are consistent with this hypothesis. The time required for an entire population to achieve maximum lipid content is considerably longer than that required for a single cell, due to the variation in response time among cells. In this study high lipid cultures were sometimes obtained by using FCM to separate high lipid cells from the remainder of the population. FCM holds much promise for strain enhancement but considerable developmental work, directed at providing more consistent results, remains to be done. 8 refs., 35 figs.

  10. High Lipid Induction in Microalgae for Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Peer M. Schenk

    2012-05-01

    Full Text Available Oil-accumulating microalgae have the potential to enable large-scale biodiesel production without competing for arable land or biodiverse natural landscapes. High lipid productivity of dominant, fast-growing algae is a major prerequisite for commercial production of microalgal oil-derived biodiesel. However, under optimal growth conditions, large amounts of algal biomass are produced, but with relatively low lipid contents, while species with high lipid contents are typically slow growing. Major advances in this area can be made through the induction of lipid biosynthesis, e.g., by environmental stresses. Lipids, in the form of triacylglycerides typically provide a storage function in the cell that enables microalgae to endure adverse environmental conditions. Essentially algal biomass and triacylglycerides compete for photosynthetic assimilate and a reprogramming of physiological pathways is required to stimulate lipid biosynthesis. There has been a wide range of studies carried out to identify and develop efficient lipid induction techniques in microalgae such as nutrients stress (e.g., nitrogen and/or phosphorus starvation, osmotic stress, radiation, pH, temperature, heavy metals and other chemicals. In addition, several genetic strategies for increased triacylglycerides production and inducibility are currently being developed. In this review, we discuss the potential of lipid induction techniques in microalgae and also their application at commercial scale for the production of biodiesel.

  11. The Potential of Microalgae Lipids for Edible Oil Production.

    Science.gov (United States)

    Huang, Yanfei; Zhang, Dongmei; Xue, Shengzhang; Wang, Meng; Cong, Wei

    2016-10-01

    The objective of this study was to evaluate the potential of oil-rich green algae, Chlorella vulgaris, Scenedesmus obliquus, and Nannochloropsis oceanica, to produce edible oil with respect to lipid and residue properties. The results showed that C. vulgaris and N. oceanica had similarly much higher lipid recovery (about 50 %) in hexane extraction than that of S. obliquus (about 25 %), and C. vulgaris had the highest content of neutral lipids among the three algae. The fatty acid compositions of neutral lipids from C. vulgaris and S. obliquus were mainly C16 and C18, resembling that of vegetable oils. ARA and EPA were the specific valuable fatty acids in lipids of N. oceanica, but the content of which was lower in neutral lipids. Phytol was identified as the major unsaponifiable component in lipids of the three algae. Combined with the evaluation of the ratios in SFA/MUFA/PUFA, (n-6):(n-3) and content of free fatty acids, lipids obtained from C. vulgaris displayed the great potential for edible oil production. Lipids of N. oceanica showed the highest antioxidant activity, and its residue contained the largest amounts of protein as well as the amino acid compositions were greatly beneficial to the health of human beings.

  12. EFFECT OF VARIOUS VEGETABLE OILS ON THE LIPID PROFILE AND ANTIOXIDANT STATUS IN HYPERCHOLESTEROLAEMIC WISTAR RATS- A COMPARATIVE STUDY

    Directory of Open Access Journals (Sweden)

    Prasad Ravindra Manjeshwar

    2017-02-01

    Full Text Available BACKGROUND Various vegetable oils are used for cooking foods in India. Controversies have been created that consumption of certain vegetable oils cause atherogenesis. A little is known about the effect of vegetable oils in hypercholesterolaemic conditions. Hypercholesterolaemia, mainly the increased plasma Low-Density Lipoprotein (LDL cholesterol levels and Reactive Oxygen Species (ROS has been implicated in the early development and progression of atherosclerosis and Coronary Heart Diseases (CHD. Current study is designed to assess the effect of various vegetable oils such as coconut, sunflower, palm, olive oil and vanaspati on lipid profile and oxidative stress parameters in rats fed on a high-cholesterol diet. MATERIALS AND METHODS Hypercholesterolaemia is induced by supplementing cholesterol with the basal diet. Reference dose of various vegetable oils were administered once daily for 90 days. After the treatment period of 90 days, triacylglycerol, total cholesterol, HDL cholesterol, LDL cholesterol, VLDL cholesterol and oxidative stress parameters are estimated and analysed. RESULTS In the present study, we observed the lipid-lowering effect of various vegetable oils in rats fed with high-cholesterol diet. Administration of cholesterol showed increased level of lipid profile. Concurrent administration of various vegetable oils with high-cholesterol diet caused a significant decrease in serum total cholesterol, LDL and VLDL cholesterol. This conclusion is made based on the observation that the vegetable oils were able to restore, at least partially, the lipid profile of hypercholesterolaemic rats. A decline of antioxidant status associated with an increase in lipid peroxidation was observed in all the vegetable oil treated groups. Among the oils, coconut oil showed a mild increase in High-Density Lipoprotein (HDL and least increase in lipid peroxidation compared to other vegetable oils treated groups. CONCLUSION Results suggest that the

  13. Reducible cationic lipids for gene transfer.

    Science.gov (United States)

    Wetzer, B; Byk, G; Frederic, M; Airiau, M; Blanche, F; Pitard, B; Scherman, D

    2001-01-01

    One of the main challenges of gene therapy remains the increase of gene delivery into eukaryotic cells. We tested whether intracellular DNA release, an essential step for gene transfer, could be facilitated by using reducible cationic DNA-delivery vectors. For this purpose, plasmid DNA was complexed with cationic lipids bearing a disulphide bond. This reduction-sensitive linker is expected to be reduced and cleaved in the reducing milieu of the cytoplasm, thus potentially improving DNA release and consequently transfection. The DNA--disulphide-lipid complexation was monitored by ethidium bromide exclusion, and the size of complexes was determined by dynamic light scattering. It was found that the reduction kinetics of disulphide groups in DNA--lipid complexes depended on the position of the disulphide linker within the lipid molecule. Furthermore, the internal structure of DNA--lipid particles was examined by small-angle X-ray scattering before and after lipid reduction. DNA release from lipid complexes was observed after the reduction of disulphide bonds of several lipids. Cell-transfection experiments suggested that complexes formed with selected reducible lipids resulted in up to 1000-fold higher reporter-gene activity, when compared with their analogues without disulphide bonds. In conclusion, reduction-sensitive groups introduced into cationic lipid backbones potentially allow enhanced DNA release from DNA--lipid complexes after intracellular reduction and represent a tool for improved vectorization. PMID:11389682

  14. Preparation and characterization of tetrandrine-phospholipid complex loaded lipid nanocapsules as potential oral carriers

    Directory of Open Access Journals (Sweden)

    Zhao YQ

    2013-10-01

    Full Text Available Yi-qing Zhao, Li-ping Wang, Chao Ma, Kun Zhao, Ying Liu, Nian-ping FengSchool of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, People’s Republic of ChinaBackground: Tetrandrine is an active constituent that is extracted from the root tuber of the Chinese herb Stephania tetrandra S. Moore. It has shown various pharmacological effects, such as antitumor activity, multidrug resistance reversal, and hepatic fibrosis resistance. In clinical applications, it has been used to treat hypertension, pneumosilicosis, and lung cancer. However, the poor water solubility of tetrandrine has limited its application. In this study, a newly emerging oral drug carrier of phospholipid complex loaded lipid nanocapsules was developed to improve the oral bioavailability of tetrandrine.Methods: The phospholipid complex was prepared with the solvent-evaporation method to enhance the liposolubility of tetrandrine. The formation of the phospholipid complex was confirmed with a solubility study, infrared spectroscopy, and a differential scanning calorimetry (DSC analysis. The tetrandrine-phospholipid complex loaded lipid nanocapsules (TPC-LNCs were prepared using the phase inversion method. Lyophilization was performed with mannitol (10% as a cryoprotectant. TPC-LNCs were characterized according to their particle size, zeta potential, encapsulation efficiency, morphology by transmission electron microscopy, and crystallinity by DSC. In addition, the in vitro release of tetrandrine from TPC-LNCs was examined to potentially illustrate the in vivo release behavior. The in vivo bioavailability of TPC-LNCs was studied and compared to tetrandrine tablets in rats.Results: The liposolubility of tetrandrine in n-octanol improved from 8.34 µg/mL to 35.64 µg/mL in the tetrandrine-phospholipid complex. The prepared TPC-LNCs were spherical-shaped particles with a small size of 40 nm and a high encapsulation efficiency of 93.9%. DSC measurements revealed

  15. Effect of ewe’s (semi-skimmed and whole) and cow’s milk yogurt consumption on the lipid profile of control subjects: a crossover study

    Science.gov (United States)

    Olmedilla-Alonso, Begoña; Nova-Rebato, Esther; García-González, Natalia; Martín-Diana, Ana-Belén; Fontecha, Javier; Delgado, David; Gredilla, Ana-Elisa; Bueno, Francisco; Asensio-Vegas, Carmen

    2017-01-01

    ABSTRACT Yogurt is the most widely consumed fermented milk product worldwide. Studies have mainly used milk and dairy products from cow, which have a lower fat content than those from ewe and a different lipid profile. This study investigated the effect on the lipid profile of control subjects of three different set yogurts: (a) semi-skimmed ewe´s milk yogurt (2.8% milk fat); (b) whole ewe´s milk yogurt (5.8 % milk fat); (c) cow´s milk yogurt (3 % milk fat). A randomized crossover study included 30 healthy adults (16 women) to consume 250 g/yogurt/day during three consecutive 5-weeks periods separated by 4-week washouts. Blood samples were collected at the start and end of each period for the analysis of serum cholesterol (total, HDL-, LDL-) and triglycerides. We found no differences in the serum concentrations of lipid and lipoprotein fractions of the volunteers after the intake of any of the three types of yogurts. When the volunteers were grouped into two risk groups of risk according to their total cholesterol/HDL cholesterol ratio, the same differences between the groups in terms of the cholesterol (HDL-, LDL-) and triglyceride responses at baseline and after yogurt intake were found, with no effects due to the different types of yogurts. Moreover, we performed compositional analysis of the yogurts including determination of protein, fat, minerals and fatty acids (FA). Contents in protein, calcium, magnesium, non-protein nitrogen and some FA (mainly short-chain-FA) were higher for ewe’s than for cow’s milk yogurt. n6-n3 ratio was lower in the ewe’s milk yogurt. In conclusion, yogurt intake, from ewe’s and cow’s milk, at levels of consumption compatible with a varied diet, neither decreases nor increases plasma lipoprotein cholesterol levels in apparently healthy individuals. As ewe’s milk yogurt has a high content of macro- and micronutrients, certain target populations could benefit from its consumption. PMID:29151833

  16. Progresses in studies on 2-alkylcyclobutanones in irradiated lipid-containing foods

    International Nuclear Information System (INIS)

    Zhang Haiwei; Ha Yiming; Wang Feng

    2007-01-01

    When foods are irradiated, the free fatty acids and triacylglycerides in the food are decomposed to 2-alkylcyclobutanones (2-ACBs), which have been one of the focuses in food irradiation studies since they were dis- covered in irradiated lipid-containing foods. As specific markers, 2-ACBs could be used to detect irradiated food. The production and stability of 2-ACBs are affected strongly by the irradiation does and temperature and preservation conditions, etc. On the other hand, potential health hazard assessments of 2-ACBs have been studied extensively. Re- cent progresses in 2-ACBs detecting methods from irradiated food, toxicological studies on 2-ACBs, and factors affecting production and stability of 2-ACBs are reviewed in this paper. (authors)

  17. Quantitative assessment of the effects of beta-glucan consumption on serum lipid profile and glucose level in hypercholesterolemic subjects.

    Science.gov (United States)

    Zhu, X; Sun, X; Wang, M; Zhang, C; Cao, Y; Mo, G; Liang, J; Zhu, S

    2015-08-01

    A growing body of evidence suggests that beta-glucan derived from oats or barley can reduce cardiovascular disease risk through reductions in serum lipids. However, the effects of beta-glucan on lipid changes in hypercholesterolemic patient groups are inconsistent. The objective of this study was to identify and quantify the effect of beta-glucan, a marker of water-soluble fiber, on various lipid parameters and glucose level in hypercholesterolemic subjects. We performed a comprehensive literature search to identify the relevant randomized controlled trials (RCTs) that investigated the effects of beta-glucan consumption in hypercholesterolemic subjects. Mean differences (MDs) and 95% confidence intervals (CIs) were calculated for net changes in lipid concentrations by using fixed-effects or random-effects models according to heterogeneity. Publication bias, sensitivity analysis and subgroup analyses were also performed. Seventeen eligible RCTs with 916 subjects were included in the meta-analysis. The pooled result showed that beta-glucan consumption in hypercholesterolemic population significantly lowered the total cholesterol (TC) (MD, -0.26 mmol/L; 95% CI, -0.33 to -0.18; P consumption significantly decreased TC and LDL-cholesterol concentrations but did not affect TG, HDL-cholesterol, and glucose concentrations in hypercholesterolemic subjects. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Microwave-assisted extraction of lipid from fish waste

    Science.gov (United States)

    Rahimi, M. A.; Omar, R.; Ethaib, S.; Siti Mazlina, M. K.; Awang Biak, D. R.; Nor Aisyah, R.

    2017-06-01

    Processing fish waste for extraction of value added products such as protein, lipid, gelatin, amino acids, collagen and oil has become one of the most intriguing researches due to its valuable properties. In this study the extraction of lipid from sardine fish waste was carried out using microwave-assisted extraction (MAE) and compared with Soxhlets and Hara and Radin methods. A mixture of two organic solvents isopropanol/hexane and distilled water were used for MAE and Hara and Radin methods. Meanwhile, Soxhlet method utilized only hexane as solvent. The results show that the higher yield of lipid 80.5 mg/g was achieved using distilled water in MAE method at 10 min extraction time. Soxhlet extraction method only produced 46.6 mg/g of lipid after 4 hours of extraction time. Lowest yield of lipid was found at 15.8 mg/g using Hara and Radin method. Based on aforementioned results, it can be concluded MAE method is superior compared to the Soxhlet and Hara and Radin methods which make it an attractive route to extract lipid from fish waste.

  19. Controlling Styrene Maleic Acid Lipid Particles through RAFT.

    Science.gov (United States)

    Smith, Anton A A; Autzen, Henriette E; Laursen, Tomas; Wu, Vincent; Yen, Max; Hall, Aaron; Hansen, Scott D; Cheng, Yifan; Xu, Ting

    2017-11-13

    The ability of styrene maleic acid copolymers to dissolve lipid membranes into nanosized lipid particles is a facile method of obtaining membrane proteins in solubilized lipid discs while conserving part of their native lipid environment. While the currently used copolymers can readily extract membrane proteins in native nanodiscs, their highly disperse composition is likely to influence the dispersity of the discs as well as the extraction efficiency. In this study, reversible addition-fragmentation chain transfer was used to control the polymer architecture and dispersity of molecular weights with a high-precision. Based on Monte Carlo simulations of the polymerizations, the monomer composition was predicted and allowed a structure-function analysis of the polymer architecture, in relation to their ability to assemble into lipid nanoparticles. We show that a higher degree of control of the polymer architecture generates more homogeneous samples. We hypothesize that low dispersity copolymers, with control of polymer architecture are an ideal framework for the rational design of polymers for customized isolation and characterization of integral membrane proteins in native lipid bilayer systems.

  20. Blood lipid levels in a rural male population.

    Science.gov (United States)

    Thelin, A; Stiernström, E L; Holmberg, S

    2001-06-01

    Farmers have a low risk for cardiovascular disease, which may be related to a favourable blood lipid profile. In order to study the blood lipid levels and evaluate the effect of other cardiovascular risk factors on the blood lipid profile, this cross-sectional study was made. A total of 1013 farmers and 769 non-farming rural men in nine different Swedish counties were examined, interviewed, and replied to questionnaires. The inter-relationships between different risk factors were analysed using a multivariate linear regression model. The farmers had a significantly more favourable blood lipid profile than the non-farmers although the total cholesterol levels were almost the same for the two groups. In the total study population there were significant positive relationships between total cholesterol level and body mass index (BMI), diastolic blood pressure and smoking. The high-density lipoprotein (HDL) level was positively related to physical workload and alcohol consumption, and negatively related to BMI, waist/hip ratio and smoking. Triglyceride levels showed a positive relationship to BMI, waist/hip ratio and blood pressure. Differences between farmers and other rural males were seen, especially with respect to the effect of physical activity and psychosocial factors. Among the farmers, a negative correlation between the Karasek-Theorell authority over work index and total cholesterol, the low-density lipoprotein (LDL)/HDL ratio and triglyceride levels was observed. This study indicated that diet is of minor significance for the blood lipid profile, whereas factors such as physical activity, body weight and the waist/hip ratio, smoking, alcohol consumption, and perhaps psychosocial working conditions are major independent factors affecting the blood lipid profile most prominently among farmers, but also among non-farming rural men.

  1. Risk of misclassification with a non-fasting lipid profile in secondary cardiovascular prevention.

    Science.gov (United States)

    Klop, Boudewijn; Hartong, Simone C C; Vermeer, Henricus J; Schoofs, Mariette W C J; Kofflard, Marcel J M

    2017-09-01

    Routinely fasting is not necessary for measuring the lipid profile according to the latest European consensus. However, LDL-C tends to be lower in the non-fasting state with risk of misclassification. The extent of misclassification in secondary cardiovascular prevention with a non-fasting lipid profile was investigated. 329 patients on lipid lowering therapy for secondary cardiovascular prevention measured a fasting and non-fasting lipid profile. Cut-off values for LDL-C, non-HDL-C and apolipoprotein B were set at fasting LDL-C (calculated using the Friedewald formula), direct LDL-C, non-HDL-C and apolipoprotein B. Net misclassification fasting measurements resulted in lower LDL-C (-0.2±0.4mmol/l, Pfasting LDL-C target of fasting state. In the non-fasting state net misclassification with direct LDL-C was 5.7% (95% CI 2.1-9.2%), 4.0% (95% CI 1.0-7.4%) with non-HDL-C and 4.1% (95% CI 1.1-9.1%) with apolipoprotein B. Use of non-fasting LDL-C as treatment target in secondary cardiovascular prevention resulted in significant misclassification with subsequent risk of undertreatment, whereas non-fasting direct LDL-C, non-HDL-C and apolipoprotein B are reliable parameters. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Interaction of antimicrobial peptides with lipid membranes

    Energy Technology Data Exchange (ETDEWEB)

    Hanulova, Maria

    2008-12-15

    This study aims to investigate the difference in the interaction of antimicrobial peptides with two classes of zwitterionic peptides, phosphatidylethanolamines (PE) and phosphatidylcholines (PC). Further experiments were performed on model membranes prepared from specific bacterial lipids, lipopolysaccharides (LPS) isolated from Salmonella minnesota. The structure of the lipid-peptide aqueous dispersions was studied by small-and wide-angle X-ray diffraction during heating and cooling from 5 to 85 C. The lipids and peptides were mixed at lipid-to-peptide ratios 10-10000 (POPE and POPC) or 2-50 (LPS). All experiments were performed at synchrotron soft condensed matter beamline A2 in Hasylab at Desy in Hamburg, Germany. The phases were identified and the lattice parameters were calculated. Alamethicin and melittin interact in similar ways with the lipids. Pure POPC forms only lamellar phases. POPE forms lamellar phases at low temperatures that upon heating transform into a highly curved inverse hexagonal phase. Insertion of the peptide induced inverse bicontinuous cubic phases which are an ideal compromise between the curvature stress and the packing frustration. Melittin usually induced a mixture of two cubic phases, Im3m and Pn3m, with a ratio of lattice parameters close to 1.279, related to the underlying minimal surfaces. They formed during the lamellar to hexagonal phase transition and persisted during cooling till the onset of the gel phase. The phases formed at different lipid-to-peptide ratios had very similar lattice parameters. Epitaxial relationships existed between coexisting cubic phases and hexagonal or lamellar phases due to confinement of all phases to an onion vesicle, a vesicle with several layers consisting of different lipid phases. Alamethicin induced the same cubic phases, although their formation and lattice parameters were dependent on the peptide concentration. The cubic phases formed during heating from the lamellar phase and their onset

  3. Interaction of antimicrobial peptides with lipid membranes

    International Nuclear Information System (INIS)

    Hanulova, Maria

    2008-12-01

    This study aims to investigate the difference in the interaction of antimicrobial peptides with two classes of zwitterionic peptides, phosphatidylethanolamines (PE) and phosphatidylcholines (PC). Further experiments were performed on model membranes prepared from specific bacterial lipids, lipopolysaccharides (LPS) isolated from Salmonella minnesota. The structure of the lipid-peptide aqueous dispersions was studied by small-and wide-angle X-ray diffraction during heating and cooling from 5 to 85 C. The lipids and peptides were mixed at lipid-to-peptide ratios 10-10000 (POPE and POPC) or 2-50 (LPS). All experiments were performed at synchrotron soft condensed matter beamline A2 in Hasylab at Desy in Hamburg, Germany. The phases were identified and the lattice parameters were calculated. Alamethicin and melittin interact in similar ways with the lipids. Pure POPC forms only lamellar phases. POPE forms lamellar phases at low temperatures that upon heating transform into a highly curved inverse hexagonal phase. Insertion of the peptide induced inverse bicontinuous cubic phases which are an ideal compromise between the curvature stress and the packing frustration. Melittin usually induced a mixture of two cubic phases, Im3m and Pn3m, with a ratio of lattice parameters close to 1.279, related to the underlying minimal surfaces. They formed during the lamellar to hexagonal phase transition and persisted during cooling till the onset of the gel phase. The phases formed at different lipid-to-peptide ratios had very similar lattice parameters. Epitaxial relationships existed between coexisting cubic phases and hexagonal or lamellar phases due to confinement of all phases to an onion vesicle, a vesicle with several layers consisting of different lipid phases. Alamethicin induced the same cubic phases, although their formation and lattice parameters were dependent on the peptide concentration. The cubic phases formed during heating from the lamellar phase and their onset

  4. Triglyceride Blisters in Lipid Bilayers: Implications for Lipid Droplet Biogenesis and the Mobile Lipid Signal in Cancer Cell Membranes

    DEFF Research Database (Denmark)

    Khandelia, Himanshu; Duelund, Lars; Pakkanen, Kirsi Inkeri

    2010-01-01

    triolein molecules to the bilayer center in the form of a disordered, isotropic, mobile neutral lipid aggregate, at least 17 nm in diameter, which forms spontaneously, and remains stable on at least the microsecond time scale. The results give credence to the hotly debated existence of mobile neutral lipid...... aggregates of unknown function present in malignant cells, and to the early biogenesis of lipid droplets accommodated between the two leaflets of the endoplasmic reticulum membrane. The TO aggregates give the bilayer a blister-like appearance, and will hinder the formation of multi-lamellar phases in model...

  5. Inhibitory effects of soluble algae products (SAP) released by Scenedesmus sp. LX1 on its growth and lipid production.

    Science.gov (United States)

    Zhang, Tian-Yuan; Yu, Yin; Wu, Yin-Hu; Hu, Hong-Ying

    2013-10-01

    Soluble algal products (SAP) accumulated in culture medium via water reuse may affect the growth of microalga during the cultivation. Scenedesmus sp. LX1, a freshwater microalga, was used in this study to investigate the effect of SAP on growth and lipid production of microalga. Under the SAP concentrations of 6.4-25.8 mg L(-1), maximum algal density (K) and maximum growth rate (Rmax) of Scenedesmus sp. LX1 were decreased by 50-80% and 35-70% compared with the control group, respectively. The effect of SAP on lipid accumulation of Scenedesmus sp. LX1 was non-significant. According to hydrophilic-hydrophobic and acid-base properties, SAP was fractionized into six fractions. All of the fractions could inhibit the growth of Scenedesmus sp. LX1. Organic bases (HIB, HOB) and hydrophilic acids (HIA) showed the strongest inhibition. HIA could also decrease the lipid content of Scenedesmus sp. LX1 by 59.2%. As the inhibitory effect, SAP should be seriously treated before water reuse. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Peptide-Loaded Solid Lipid Nanoparticles Prepared through Coacervation Technique

    Directory of Open Access Journals (Sweden)

    Marina Gallarate

    2011-01-01

    Full Text Available Stearic acid solid lipid nanoparticles were prepared according to a new technique, called coacervation. The main goal of this experimental work was the entrapment of peptide drugs into SLN, which is a difficult task, since their chemical characteristics (molecular weight, hydrophilicity, and stability hamper peptide-containing formulations. Insulin and leuprolide, chosen as model peptide drugs, were encapsulated within nanoparticles after hydrophobic ion pairing with anionic surfactants. Peptide integrity was maintained after encapsulation, and nanoparticles can act in vitro as a sustained release system for peptide.

  7. Wrinkled1 accelerates flowering and regulates lipid homeostasis between oil accumulation and membrane lipid anabolism in Brassica napus

    Directory of Open Access Journals (Sweden)

    Qing eLi

    2015-11-01

    Full Text Available Wrinkled1 (WRI1 belongs to the APETALA2 transcription factor family; it is unique to plants and is a central regulator of oil synthesis in Arabidopsis. The effects of WRI1 on comprehensive lipid metabolism and plant development were unknown, especially in crop plants. This study found that BnWRI1 in Brassica napus accelerated flowering and enhanced oil accumulation in both seeds and leaves without leading to a visible growth inhibition. BnWRI1 decreased storage carbohydrates and increased soluble sugars to facilitate the carbon flux to lipid anabolism. BnWRI1 is localized to the nucleus and directly binds to the AW-box at proximal upstream regions of genes involved in fatty acid synthesis and lipid assembly. The overexpression (OE of BnWRI1 resulted in the up-regulation of genes involved in glycolysis, fatty acid synthesis, lipid assembly, and flowering. Lipid profiling revealed increased galactolipid monogalactosyldiacylglycerol (MGDG, digalactosyldiacylglycerol (DGDG, and phosphatidylcholine (PC in the leaves of OE plants, whereas it exhibited a reduced level of the galactolipids DGDG and MGDG and increased levels of PC, phosphatidylethanolamide (PE, and oil (triacylglycerol, TAG in the siliques of OE plants during the early seed development stage. These results suggest that BnWRI1 is important for homeostasis among TAG, membrane lipids and sugars, and thus facilitates flowering and oil accumulation in B. napus.

  8. Lipid raft localization of TLR2 and its co-receptors is independent of membrane lipid composition

    Directory of Open Access Journals (Sweden)

    Christine Hellwing

    2018-01-01

    Full Text Available Background Toll like receptors (TLRs are an important and evolutionary conserved class of pattern recognition receptors associated with innate immunity. The recognition of Gram-positive cell wall constituents strongly depends on TLR2. In order to be functional, TLR2 predominantly forms a heterodimer with TLR1 or TLR6 within specialized membrane microdomains, the lipid rafts. The membrane lipid composition and the physicochemical properties of lipid rafts are subject to modification by exogenous fatty acids. Previous investigations of our group provide evidence that macrophage enrichment with polyunsaturated fatty acids (PUFA induces a reordering of lipid rafts and non-rafts based on the incorporation of supplemented PUFA as well as their elongation and desaturation products. Methods In the present study we investigated potential constraining effects of membrane microdomain reorganization on the clustering of TLR2 with its co-receptors TLR1 and TLR6 within lipid rafts. To this end, RAW264.7 macrophages were supplemented with either docosahexaenoic acid (DHA or arachidonic acid (AA and analyzed for receptor expression and microdomain localization in context of TLR stimulation. Results and Conclusions Our analyses showed that receptor levels and microdomain localization were unchanged by PUFA supplementation. The TLR2 pathway, in contrast to the TLR4 signaling cascade, is not affected by exogenous PUFA at the membrane level.

  9. Optimization of 14C liquid scintillation counting of plant and soil lipids to trace short term formation, translocation and degradation of lipids

    International Nuclear Information System (INIS)

    Wiesenberg, G.L.B.; Gocke, M.; Yakov Kuzyakov

    2010-01-01

    Two powerful approaches are frequently used to trace incorporation and degradation of plant derived C in soil: 14 C labelling/chasing and analysis of lipid composition. In this study, we coupled these approaches in order to trace short term incorporation of plant derived lipids into rhizosphere and non-rhizosphere soil. Methodological optimization was required and implied 14 C liquid scintillation counting improvement for plant lipid extracts taking into account organic solvents, solvent-to-scintillation cocktail ratio, and amount of lipids. Following method optimization, 14 C data of fatty acids indicated a notable contribution of root derived lipids to rhizosphere and non-rhizosphere soil. Coupling of 14 C labelling/chasing with lipid analysis is a powerful and cheap approach for tracing of root derived C in soil allowing for estimation of C budget, for determination of C formation and translocation within plants and from plant to soil, as well as for identification of short term dynamics of specific compound classes within soil. (author)

  10. Assessing the nature of lipid raft membranes

    DEFF Research Database (Denmark)

    Niemelä, Perttu S; Ollila, Samuli; Hyvönen, Marja T

    2007-01-01

    of highly ordered lateral domains rich in sphingomyelin and cholesterol (CHOL). These domains, called functional lipid rafts, have been suggested to take part in a variety of dynamic cellular processes such as membrane trafficking, signal transduction, and regulation of the activity of membrane proteins......-scale simulations to elucidate the properties of ternary raft mixtures with CHOL, palmitoylsphingomyelin (PSM), and palmitoyloleoylphosphatidylcholine. We simulate two bilayers of 1,024 lipids for 100 ns in the liquid-ordered phase and one system of the same size in the liquid-disordered phase. The studies provide...... heterogeneity more difficult. The findings reveal aspects of the role of favored (specific) lipid-lipid interactions within rafts and clarify the prominent role of CHOL in altering the properties of the membrane locally in its neighborhood. Also, we show that the presence of PSM and CHOL in rafts leads...

  11. Transcriptional Regulation of T-Cell Lipid Metabolism: Implications for Plasma Membrane Lipid Rafts and T-Cell Function

    Directory of Open Access Journals (Sweden)

    George A. Robinson

    2017-11-01

    Full Text Available It is well established that cholesterol and glycosphingolipids are enriched in the plasma membrane (PM and form signaling platforms called lipid rafts, essential for T-cell activation and function. Moreover, changes in PM lipid composition affect the biophysical properties of lipid rafts and have a role in defining functional T-cell phenotypes. Here, we review the role of transcriptional regulators of lipid metabolism including liver X receptors α/β, peroxisome proliferator-activated receptor γ, estrogen receptors α/β (ERα/β, and sterol regulatory element-binding proteins in T-cells. These receptors lie at the interface between lipid metabolism and immune cell function and are endogenously activated by lipids and/or hormones. Importantly, they regulate cellular cholesterol, fatty acid, glycosphingolipid, and phospholipid levels but are also known to modulate a broad spectrum of immune responses. The current evidence supporting a role for lipid metabolism pathways in controlling immune cell activation by influencing PM lipid raft composition in health and disease, and the potential for targeting lipid biosynthesis pathways to control unwanted T-cell activation in autoimmunity is reviewed.

  12. Evaporation and Hydrocarbon Chain Conformation of Surface Lipid Films

    Science.gov (United States)

    Sledge, Samiyyah M.; Khimji, Hussain; Borchman, Douglas; Oliver, Alexandria; Michael, Heidi; Dennis, Emily K.; Gerlach, Dylan; Bhola, Rahul; Stephen, Elsa

    2016-01-01

    Purpose The inhibition of the rate of evaporation (Revap) by surface lipids is relevant to reservoirs and dry eye. Our aim was to test the idea that lipid surface films inhibit Revap. Methods Revap were determined gravimetrically. Hydrocarbon chain conformation and structure were measured using a Raman microscope. Six 1-hydroxyl hydrocarbons (11–24 carbons in length) and human meibum were studied. Reflex tears were obtained from a 62-year-old male. Results The Raman scattering intensity of the lipid film deviated by about 7 % for hydroxyl lipids and varied by 21 % for meibum films across the entire film at a resolution of 5 µm2. All of the surface lipids were ordered. Revap of the shorter chain hydroxyl lipids were slightly (7%) but significantly lower compared with the longer chain hydroxyl lipids. Revap of both groups was essentially similar to that of buffer. A hydroxyl lipid film did not influence Revap over an estimated average thickness range of 0.69 to >6.9 µm. Revap of human tears and buffer with and without human meibum (34.4 µm thick) was not significantly different. Revap of human tears was not significantly different from buffer. Conclusions Human meibum and hydroxyl lipids, regardless of their fluidity, chain length, or thickness did not inhibit Revap of buffer or tears even though they completely covered the surface. It is unlikely that hydroxyl lipids can be used to inhibit Revap of reservoirs. Our data do not support the widely accepted (yet unconfirmed) idea that the tear film lipid layer inhibits Revap of tears. PMID:27395776

  13. Major Lipid Body Protein: A Conserved Structural Component of Lipid Body Accumulated during Abiotic Stress in S. quadricauda CASA-CC202

    Directory of Open Access Journals (Sweden)

    Arumugam Muthu

    2016-11-01

    Full Text Available Abiotic stress in oleaginous microalgae enhances lipid accumulation and is stored in a specialised organelle called lipid droplets (LDs. Both the LDs and body are enriched with major lipid droplet protein (MLDP. It serves as a major structural component and also plays a key role in recruiting other proteins and enzymes involved in lipid body maturation. In the present study, the presence of MLDP was detected in two abiotic stress condition namely nitrogen starvation and salt stress condition. Previous research reveals that nitrogen starvation enhances lipid accumulation. Therefore, the effect of salt on growth, biomass yield, and fatty acid profile is studied in detail. The specific growth rate of S. quadricauda under the salt stress of 10mM concentration is about 0.174μ and in control, the SGR is 0.241μ. An increase in the doubling time of the cells shows that the rate of cell division decreases during salt stress (2.87–5.17. The dry biomass content also decreased drastically at 50mM salt-treated cells (129mg/L compared to control (236mg/L on the day 20. The analysis of fatty acid composition also revealed that there is a 20% decrease in the saturated fatty acid level and 19.9% increment in monounsaturated fatty acid level, which makes salt-mediated lipid accumulation as a suitable biodiesel precursor.

  14. An ER protein functionally couples neutral lipid metabolism on lipid droplets to membrane lipid synthesis in the ER.

    Science.gov (United States)

    Markgraf, Daniel F; Klemm, Robin W; Junker, Mirco; Hannibal-Bach, Hans K; Ejsing, Christer S; Rapoport, Tom A

    2014-01-16

    Eukaryotic cells store neutral lipids such as triacylglycerol (TAG) in lipid droplets (LDs). Here, we have addressed how LDs are functionally linked to the endoplasmic reticulum (ER). We show that, in S. cerevisiae, LD growth is sustained by LD-localized enzymes. When LDs grow in early stationary phase, the diacylglycerol acyl-transferase Dga1p moves from the ER to LDs and is responsible for all TAG synthesis from diacylglycerol (DAG). During LD breakdown in early exponential phase, an ER membrane protein (Ice2p) facilitates TAG utilization for membrane-lipid synthesis. Ice2p has a cytosolic domain with affinity for LDs and is required for the efficient utilization of LD-derived DAG in the ER. Ice2p breaks a futile cycle on LDs between TAG degradation and synthesis, promoting the rapid relocalization of Dga1p to the ER. Our results show that Ice2p functionally links LDs with the ER and explain how cells switch neutral lipid metabolism from storage to consumption. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  15. An ER Protein Functionally Couples Neutral Lipid Metabolism on Lipid Droplets to Membrane Lipid Synthesis in the ER

    Directory of Open Access Journals (Sweden)

    Daniel F. Markgraf

    2014-01-01

    Full Text Available Eukaryotic cells store neutral lipids such as triacylglycerol (TAG in lipid droplets (LDs. Here, we have addressed how LDs are functionally linked to the endoplasmic reticulum (ER. We show that, in S. cerevisiae, LD growth is sustained by LD-localized enzymes. When LDs grow in early stationary phase, the diacylglycerol acyl-transferase Dga1p moves from the ER to LDs and is responsible for all TAG synthesis from diacylglycerol (DAG. During LD breakdown in early exponential phase, an ER membrane protein (Ice2p facilitates TAG utilization for membrane-lipid synthesis. Ice2p has a cytosolic domain with affinity for LDs and is required for the efficient utilization of LD-derived DAG in the ER. Ice2p breaks a futile cycle on LDs between TAG degradation and synthesis, promoting the rapid relocalization of Dga1p to the ER. Our results show that Ice2p functionally links LDs with the ER and explain how cells switch neutral lipid metabolism from storage to consumption.

  16. Interaction between lipid monolayers and poloxamer 188: An X-ray reflectivity and diffraction study

    DEFF Research Database (Denmark)

    Wu, G.H.; Majewski, J.; Ege, C.

    2005-01-01

    The mechanism by which poloxamer 188 (P188) seals a damaged cell membrane is examined using the lipid monolayer as a model system. X-ray reflectivity and grazing-incidence x-ray diffraction results show that at low nominal lipid density, P188, by physically occupying the available area and phase ...

  17. Lipoproteins in Drosophila melanogaster—Assembly, Function, and Influence on Tissue Lipid Composition

    Science.gov (United States)

    Palm, Wilhelm; Sampaio, Julio L.; Brankatschk, Marko; Carvalho, Maria; Mahmoud, Ali; Shevchenko, Andrej; Eaton, Suzanne

    2012-01-01

    Interorgan lipid transport occurs via lipoproteins, and altered lipoprotein levels correlate with metabolic disease. However, precisely how lipoproteins affect tissue lipid composition has not been comprehensively analyzed. Here, we identify the major lipoproteins of Drosophila melanogaster and use genetics and mass spectrometry to study their assembly, interorgan trafficking, and influence on tissue lipids. The apoB-family lipoprotein Lipophorin (Lpp) is the major hemolymph lipid carrier. It is produced as a phospholipid-rich particle by the fat body, and its secretion requires Microsomal Triglyceride Transfer Protein (MTP). Lpp acquires sterols and most diacylglycerol (DAG) at the gut via Lipid Transfer Particle (LTP), another fat body-derived apoB-family lipoprotein. The gut, like the fat body, is a lipogenic organ, incorporating both de novo–synthesized and dietary fatty acids into DAG for export. We identify distinct requirements for LTP and Lpp-dependent lipid mobilization in contributing to the neutral and polar lipid composition of the brain and wing imaginal disc. These studies define major routes of interorgan lipid transport in Drosophila and uncover surprising tissue-specific differences in lipoprotein lipid utilization. PMID:22844248

  18. Characteristics of lipids and their feeding value in swine diets

    OpenAIRE

    Kerr, Brian J.; Kellner, Trey A.; Shurson, Gerald C.

    2015-01-01

    In livestock diets, energy is one of the most expensive nutritional components of feed formulation. Because lipids are a concentrated energy source, inclusion of lipids are known to affect growth rate and feed efficiency, but are also known to affect diet palatability, feed dustiness, and pellet quality. In reviewing the literature, the majority of research studies conducted on the subject of lipids have focused mainly on the effects of feeding presumably high quality lipids on growth perform...

  19. A criterion to identify the equilibration time in lipid bilayer simulations

    Directory of Open Access Journals (Sweden)

    Rodolfo D. Porasso

    2012-11-01

    Full Text Available With the aim of establishing a criterion for identifying when a lipid bilayer has reached steady state using the molecular dynamics simulation technique, lipid bilayers of different composition in their liquid crystalline phase were simulated in aqueous solution in presence of CaCl_2 as electrolyte, at different concentration levels. In this regard, we used two different lipid bilayer systems: one composed by 288 DPPC (DiPalmitoylPhosphatidylCholine and another constituted by 288 DPPS (DiPalmitoylPhosphatidylSerine. In this sense, for both type of lipid bilayers, we have studied the temporal evolution of some lipids properties, such as the surface area per lipid, the deuterium order parameter, the lipid hydration and the lipid-calcium coordination. From their analysis, it became evident how each property has a different time to achieve equilibrium. The following order was found, from faster property to slower property: coordination of ions $approx$ deuterium order parameter > area per lipid $approx$ hydration. Consequently, when the hydration of lipids or the mean area per lipid are stable, we can ensure that the lipid membrane has reached the steady state.

  20. Organization of lipids in the tear film: a molecular-level view.

    Directory of Open Access Journals (Sweden)

    Alicja Wizert

    Full Text Available Biophysical properties of the tear film lipid layer are studied at the molecular level employing coarse grain molecular dynamics (MD simulations with a realistic model of the human tear film. In this model, polar lipids are chosen to reflect the current knowledge on the lipidome of the tear film whereas typical Meibomian-origin lipids are included in the thick non-polar lipids subphase. Simulation conditions mimic those experienced by the real human tear film during blinks. Namely, thermodynamic equilibrium simulations at different lateral compressions are performed to model varying surface pressure, and the dynamics of the system during a blink is studied by non-equilibrium MD simulations. Polar lipids separate their non-polar counterparts from water by forming a monomolecular layer whereas the non-polar molecules establish a thick outermost lipid layer. Under lateral compression, the polar layer undulates and a sorting of polar lipids occurs. Moreover, formation of three-dimensional aggregates of polar lipids in both non-polar and water subphases is observed. We suggest that these three-dimensional structures are abundant under dynamic conditions caused by the action of eye lids and that they act as reservoirs of polar lipids, thus increasing stability of the tear film.

  1. Lipids of Dietzia sp. A14101. Part I: A study of the production dynamics of surface-active compounds.

    Science.gov (United States)

    Hvidsten, Ina; Mjøs, Svein Are; Holmelid, Bjarte; Bødtker, Gunhild; Barth, Tanja

    2017-11-01

    Dietzia sp. A14101 belonging to the genus Dietzia (Gram-positive bacteria, Actinomycetes, high G+C content of DNA) was isolated from an oil reservoir model column inoculated with oil-field bacteria (Bødtker et al., 2009). Low interfacial tension (IFT) values were obtained by studying intact strain cells grown on water-immiscible hydrocarbons (HC) (Kowalewski et al. (2004), Kowalewski et al. (2005). Further investigations showed that the adaptation mechanism of Dietzia sp. A14101 to toxic water-immiscible HC involved changes both on the level of fatty acids content and in the physical properties of the cellular surface (development of the negative cellular surface charge and an increased in hydrophobicity) (Hvidsten et al., 2015b). However, these changes could not explain the low IFT values observed in earlier studies of this strain. Generally, low IFT imply a production of surface active compounds of low MW that are lipids by structure (Rosenberg and Ron, 1999). In this paper, it is shown that Dietzia sp. A14101 produces a range of glycolipids on all substrates. The amount of trehalose-containing lipids increases when the strain is grown on hydrocarbons. The production peak seems to coincide with the exponential growth phase, and such increased glycolipid synthesis continues throughout the stationary phase. The results indicate that only low amounts of the hydrocarbon substrate is incorporated directly into the glycolipids produced. Most of the hydrocarbon substrate seems to be employed for the biosynthesis of the neutral lipids and higher amounts of biomass were generated on HC substrates compared to incubations on non-HC substrates. The lipid content of the cell was determined as the total lipid extract (TLE), and was further fractionated (SPE). The hydrophobic and hydrophilic moieties of the isolated surface active compounds were determined (GC-MS, TLC, DART, LC-MS). The changes in the lipid content during the culture development were monitored by 1D and 2D TLC

  2. Solid lipid nanoparticles for parenteral drug delivery

    NARCIS (Netherlands)

    Wissing, S.A.; Kayser, Oliver; Muller, R.H.

    2004-01-01

    This review describes the use of nanoparticles based on solid lipids for the parenteral application of drugs. Firstly, different types of nanoparticles based on solid lipids such as "solid lipid nanoparticles" (SLN), "nanostructured lipid carriers" (NLC) and "lipid drug conjugate" (LDC)

  3. Molecular modeling of proteinlike inclusions in lipid bilayers: lipid-mediated interactions.

    Science.gov (United States)

    Kik, Richard A; Leermakers, Frans A M; Kleijn, J Mieke

    2010-02-01

    We investigated the insertion of transmembrane structures in a lipid bilayer and their interactions using self-consistent field theory. The lipids are coarse-grained on a united-atom level and consist of a phosphatidylcholinelike headgroup and two hydrophobic tails. The inclusions, acting as simple models for proteins that span biological membranes, are rigid rods (radius R ) with a hydrophobic surface and hydrophilic end caps. The insertion free energy Omega of an individual rod is strongly regulated by the affinity between its hydrophobic surface and the lipid tails. This affinity also controls the best match of the hydrophobic length of the rod with that of the bilayer. The line tension tau(=Omega/2piR) is practically independent of R . The perturbations in the bilayer as a function of distance from the inclusion, have the shape of a damped oscillation. The wavelength and decay length are related to the elastic properties of the bilayer and do not depend on R . These results are used to analyze how the lipid matrix affects the interaction between transmembrane objects, for computational reasons considering the limit of R-->infinity . Contributions on different length scales can be distinguished: (i) a long-range elastic interaction, which is an exponentially decaying oscillation; (ii) an exponentially decaying repulsion on an intermediate length scale, resulting from the loss of conformational entropy of the lipid tails; and (iii) a short-range interaction due to the finite compressibility of the lipid tails, which manifests either as a depletion attraction if there is no affinity between the tails and the inclusions' surface or, otherwise, as an oscillatory structural force.

  4. Formulation of a Novel Oxybenzone-Loaded Nanostructured Lipid Carriers (NLCs)

    OpenAIRE

    Sanad, Rania A.; AbdelMalak, Nevine Shawky; elBayoomy, Tahany S.; Badawi, Alia A.

    2010-01-01

    The objective of the current study was to formulate oxybenzone into nanostructured lipid carriers (NLCs) to enhance its sunscreening efficacy and safety. NLCs of oxybenzone were prepared by the solvent diffusion method. A complete 23 factorial design was used for the evaluation of the prepared oxybenzone NLCs. The study design involves the investigation of the effect of three independent variables namely liquid lipid type (Miglyol 812 and oleic acid), liquid lipid concentration (15% and 30%),...

  5. Dietary fructose and risk of metabolic syndrome in adults: Tehran Lipid and Glucose study.

    Science.gov (United States)

    Hosseini-Esfahani, Firoozeh; Bahadoran, Zahra; Mirmiran, Parvin; Hosseinpour-Niazi, Somayeh; Hosseinpanah, Farhad; Azizi, Fereidoun

    2011-07-12

    Studies have shown that the excessive fructose intake may induce adverse metabolic effects. There is no direct evidence from epidemiological studies to clarify the association between usual amounts of fructose intake and the metabolic syndrome. The aim this study was to determine the association of fructose intake and prevalence of metabolic syndrome (MetS) and its components in Tehranian adults. This cross-sectional population based study was conducted on 2537 subjects (45% men) aged 19-70 y, participants of the Tehran Lipid and Glucose Study (2006-2008). Dietary data were collected using a validated 168 item semi-quantitative food frequency questionnaire. Dietary fructose intake was calculated by sum of natural fructose (NF) in fruits and vegetables and added fructose (AF) in commercial foods. MetS was defined according to the modified NCEP ATP III for Iranian adults. The mean ages of men and women were 40.5 ± 13.6 and 38.6 ± 12.8 years, respectively. Mean total dietary fructose intakes were 46.5 ± 24.5 (NF: 19.6 ± 10.7 and AF: 26.9 ± 13.9) and 37.3 ± 24.2 g/d (NF: 18.6 ± 10.5 and AF: 18.7 ± 13.6) in men and women, respectively. Compared with those in the lowest quartile of fructose intakes, men and women in the highest quartile, respectively, had 33% (95% CI, 1.15-1.47) and 20% (95% CI, 1.09-1.27) higher risk of the metabolic syndrome; 39% (CI, 1.16-1.63) and 20% (CI, 1.07-1.27) higher risk of abdominal obesity; 11% (CI, 1.02-1.17) and 9% (CI, 1.02-1.14) higher risk of hypertension; and 9% (CI, 1-1.15) and 9% (1.04-1.12) higher risk of impaired fasting glucose. Higher consumption of dietary fructose may have adverse metabolic effects.

  6. Polymer-Induced Swelling of Solid-Supported Lipid Membranes

    Directory of Open Access Journals (Sweden)

    Martin Kreuzer

    2015-12-01

    Full Text Available In this paper, we study the interaction of charged polymers with solid-supported 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC membranes by in-situ neutron reflectivity. We observe an enormous swelling of the oligolamellar lipid bilayer stacks after incubation in solutions of poly(allylamine hydrochloride (PAH in D2O. The positively charged polyelectrolyte molecules interact with the lipid bilayers and induce a drastic increase in their d-spacing by a factor of ~4. Temperature, time, and pH influence the swollen interfacial lipid linings. From our study, we conclude that electrostatic interactions introduced by the adsorbed PAH are the main cause for the drastic swelling of the lipid coatings. The DMPC membrane stacks do not detach from their solid support at T > Tm. Steric interactions, also introduced by the PAH molecules, are held responsible for the stabilizing effect. We believe that this novel system offers great potential for fundamental studies of biomembrane properties, keeping the membrane’s natural fluidity and freedom, decoupled from a solid support at physiological conditions.

  7. Understanding Detergent Effects on Lipid Membranes: A Model Study of Lysolipids

    DEFF Research Database (Denmark)

    Henriksen, Jonas Rosager; Andresen, Thomas Lars; Feldborg, Lise Nørkjær

    2010-01-01

    Lysolipids and fatty acids are the natural products formed by the hydrolysis of phospholipids. Lysolipids and fatty acids form micelles in solution and acts as detergents in the presence of lipid membranes. In this study, we investigate the detergent strength of a homologous series of lyso......-chain mismatch between LPC and POPC determines the magnitude of the membrane mechanical perturbation per LPC molecule in the membrane. Finally, the three-stage model describing detergent membrane interaction has been extended by a parameter D-MCI, which governs the membrane curvature stability in the detergent...

  8. Biosynthesis and function of plant lipids

    International Nuclear Information System (INIS)

    Thomson, W.W.; Mudd, J.B.; Gibbs, M.

    1983-01-01

    The Sixth Annual Symposium in Botany and Plant Physiology was held January 13-15, 1983, at the University of California, Riverside. This volume comprises the papers that were presented. Subjects discussed at the symposium covered a wide range in the field of plant lipids. Biosynthesis of lipids occupied an important fraction of the presentations at the symposium. Subjects included detailed studies of the enzymes of fatty acid synthesis, several discussions of the incorporation of fatty acids into glycerolipids and the further modification of the fatty acids, and the synthesis of glycerolipids and desaturation of fatty acids in both maturing oilseeds and chloroplasts. The physicochemical studies of glycerolipids and sterols in artificial membranes have led to distinct conclusions about their behaviour which must be relevant in the biological membrane. Results on the functional consequences of modifying the galactolipid composition in the chloroplast were an encouraging sign of progress in the attempts to relate membrane lipid composition to physiological function

  9. Quantitative optical microscopy and micromanipulation studies on the lipid bilayer membranes of giant unilamellar vesicles

    DEFF Research Database (Denmark)

    Bagatolli, Luis; Needham, David

    2014-01-01

    to study composition-structure-property materials relationships of free-standing lipid bilayer membranes. Because their size (~5 to 100 m diameter) that is well above the resolution limit of regular light microscopes, GUVs are suitable membrane models for optical microscopy and micromanipulation...

  10. Moringa Leaves Prevent Hepatic Lipid Accumulation and Inflammation in Guinea Pigs by Reducing the Expression of Genes Involved in Lipid Metabolism.

    Science.gov (United States)

    Almatrafi, Manal Mused; Vergara-Jimenez, Marcela; Murillo, Ana Gabriela; Norris, Gregory H; Blesso, Christopher N; Fernandez, Maria Luz

    2017-06-22

    To investigate the mechanisms by which Moringa oleifera leaves (ML) modulate hepatic lipids, guinea pigs were allocated to either control (0% ML), 10% Low Moringa (LM) or 15% High Moringa (HM) diets with 0.25% dietary cholesterol to induce hepatic steatosis. After 6 weeks, guinea pigs were sacrificed and liver and plasma were collected to determine plasma lipids, hepatic lipids, cytokines and the expression of genes involved in hepatic cholesterol (CH) and triglyceride (TG) metabolism. There were no differences in plasma lipids among groups. A dose-response effect of ML was observed in hepatic lipids (CH and TG) with the lowest concentrations in the HM group ( p < 0.001), consistent with histological evaluation of lipid droplets. Hepatic gene expression of diglyceride acyltransferase-2 and peroxisome proliferator activated receptor-γ, as well as protein concentrations interleukin (IL)-1β and interferon-γ, were lowest in the HM group ( p < 0.005). Hepatic gene expression of cluster of differentiation-68 and sterol regulatory element binding protein-1c were 60% lower in both the LM and HM groups compared to controls ( p < 0.01). This study demonstrates that ML may prevent hepatic steatosis by affecting gene expression related to hepatic lipids synthesis resulting in lower concentrations of cholesterol and triglycerides and reduced inflammation in the liver.

  11. A new in vitro lipid digestion - in vivo absorption model to evaluate the mechanisms of drug absorption from lipid-based formulations.

    Science.gov (United States)

    Crum, Matthew F; Trevaskis, Natalie L; Williams, Hywel D; Pouton, Colin W; Porter, Christopher J H

    2016-04-01

    In vitro lipid digestion models are commonly used to screen lipid-based formulations (LBF), but in vitro-in vivo correlations are in some cases unsuccessful. Here we enhance the scope of the lipid digestion test by incorporating an absorption 'sink' into the experimental model. An in vitro model of lipid digestion was coupled directly to a single pass in situ intestinal perfusion experiment in an anaesthetised rat. The model allowed simultaneous real-time analysis of the digestion and absorption of LBFs of fenofibrate and was employed to evaluate the influence of formulation digestion, supersaturation and precipitation on drug absorption. Formulations containing higher quantities of co-solvent and surfactant resulted in higher supersaturation and more rapid drug precipitation in vitro when compared to those containing higher quantities of lipid. In contrast, when the same formulations were examined using the coupled in vitro lipid digestion - in vivo absorption model, drug flux into the mesenteric vein was similar regardless of in vitro formulation performance. For some drugs, simple in vitro lipid digestion models may underestimate the potential for absorption from LBFs. Consistent with recent in vivo studies, drug absorption for rapidly absorbed drugs such as fenofibrate may occur even when drug precipitation is apparent during in vitro digestion.

  12. Protective effect of morin on lipid peroxidation and lipid profile in ammonium chloride-induced hyperammonemic rats

    OpenAIRE

    S Subash; P Subramanian

    2012-01-01

    Objective: To evaluated the protective effects of morin (3, 5, 7, 2', 4'-pentahydroxyflavone) on lipid peroxidation and lipid levels during ammonium chloride (AC) induced hyperammonemia in experimental rats. Methods: Thirty two male albino Wistar rats, which are weighing between 180-200 g were used for the study. The hyperammonemia was induced by administration of 100 mg/kg body weight (i.p. ) thrice in a week of AC for 8 weeks. Rats were treated with morin at dose (30 mg/kg bo...

  13. A study on characteristic of glass dosimeter according to grade change of tube current

    Energy Technology Data Exchange (ETDEWEB)

    Son, Jin Hyun; Kim, Seong Ho; Mun, Hyun Jun; Kim, Lyun Kyun; Son, In Hwa; Kim, Young Jun; Min, Jung Whan [Dept. of Radiological Science, Shingu University, Sungnam (Korea, Republic of); Kim, Ki Won [Dept. of Radiology, Samsung Medical Center, Seoul (Korea, Republic of)

    2014-06-15

    This study was evaluated the linearity and reproducibility according to dose, and reproducibility according to delay time by changing tube current amount (5 mAs, 10 mAs, 16 mAs, 20 mAs, 25 mAs, 32 mAs respectively, which are low energy radiations) using Glass Dosimeter (GD) and piranha semiconductor dosimeter which are used for measuring exposure dose. Measurements of radiation dose were performed using external detector of piranha 657 which is multi-function QA device (RTI Electronic, Sweden). Conditions of measurement were 80 kVp, SSD 100 and exposure region is 10 cm x 10 cm. Glass dosimeter was exposed to radiation. Twenty-four glass dosimeters were divided into six groups (5 mAs, 10 mAs, 16 mAs, 20 mAs, 25 mAs, 32 mAs respectively), then measured. This study was resulted by measuring the linearity and reproducibility according to change of tube current in low energy field. In dose characteristic of GD, this study could be useful as previous study with regard to dose characteristic according to change of tube voltage in low energy field.

  14. Effect of combined gliclazide/metformin treatment on oxidative stress, lipid profile, and hepatorenal functions in type 2 diabetic patients

    Directory of Open Access Journals (Sweden)

    Mansour Alsharidah

    2018-01-01

    Full Text Available Background: Type 2 diabetes is a chronic condition that requires pharmacotherapy interventions. Metformin and gliclazide are widely used drugs in monotherapy. However, their complementary action made utilization of the combination of these drugs an appealing approach. Aims: The study compared major therapeutic potentials of combined metformin/gliclazide treatment over metformin monotherapy based on the following parameters: oxidative stress, lipid profile, and hepatorenal functions. Subjects and methods: This is a comparative study was conducted from March 2015 to March 2016. The study screened 80 type 2 diabetic patients, of which 40 patients underwent combined metformin + gliclazide therapy (500 mg BD + 80 mg OD, respectively. The other 40 were matched for age and duration of diabetes mellitus with the previous group and received metformin monotherapy (500 mg BD. The levels of fasting blood glucose (FBG, total glycated hemoglobin (HbA1c, lipid peroxidation, total antioxidant capacity, serum creatinine, aspartate and alanine transaminases, total cholesterol, triglycerides, high-density lipoproteins, and low-density lipoproteins were measured according to the standard methods. Results: Oxidative stress, lipid profile, and hepatorenal functions were comparable in patients of both groups. However, patients on metformin treatment showed significantly lower levels of FBG [7.61 (6.70–8.89 mmol/L vs. 9.00 (7.30–10.68 mmol/L; P = .022] and HBA1c [7.00 (6.40–7.65% vs. 8.20 (7.20–9.75%; P < .001] compared to those on combined therapy. Conclusion: Oxidative stress, lipids profile, and hepatorenal functions were not different in patients who were on combined metformin/gliclazide therapy and compared to those metformin alone. In contrast, glycemic control was poor in the diabetic patients undergoing combined therapy. Keywords: Diabetes mellitus, Gliclazide, Glucose, Lipids, Metformin, Oxidative stress

  15. GDSL lipases modulate immunity through lipid homeostasis in rice.

    Science.gov (United States)

    Gao, Mingjun; Yin, Xin; Yang, Weibing; Lam, Sin Man; Tong, Xiaohong; Liu, Jiyun; Wang, Xin; Li, Qun; Shui, Guanghou; He, Zuhua

    2017-11-01

    Lipids and lipid metabolites play important roles in plant-microbe interactions. Despite the extensive studies of lipases in lipid homeostasis and seed oil biosynthesis, the involvement of lipases in plant immunity remains largely unknown. In particular, GDSL esterases/lipases, characterized by the conserved GDSL motif, are a subfamily of lipolytic enzymes with broad substrate specificity. Here, we functionally identified two GDSL lipases, OsGLIP1 and OsGLIP2, in rice immune responses. Expression of OsGLIP1 and OsGLIP2 was suppressed by pathogen infection and salicylic acid (SA) treatment. OsGLIP1 was mainly expressed in leaf and leaf sheath, while OsGLIP2 showed high expression in elongating internodes. Biochemical assay demonstrated that OsGLIP1 and OsGLIP2 are functional lipases that could hydrolyze lipid substrates. Simultaneous down-regulation of OsGLIP1 and OsGLIP2 increased plant resistance to both bacterial and fungal pathogens, whereas disease resistance in OsGLIP1 and OsGLIP2 overexpression plants was significantly compromised, suggesting that both genes act as negative regulators of disease resistance. OsGLIP1 and OsGLIP2 proteins mainly localize to lipid droplets and the endoplasmic reticulum (ER) membrane. The proper cellular localization of OsGLIP proteins is indispensable for their functions in immunity. Comprehensive lipid profiling analysis indicated that the alteration of OsGLIP gene expression was associated with substantial changes of the levels of lipid species including monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG). We show that MGDG and DGDG feeding could attenuate disease resistance. Taken together, our study indicates that OsGLIP1 and OsGLIP2 negatively regulate rice defense by modulating lipid metabolism, thus providing new insights into the function of lipids in plant immunity.

  16. Lysosomal degradation of membrane lipids.

    Science.gov (United States)

    Kolter, Thomas; Sandhoff, Konrad

    2010-05-03

    The constitutive degradation of membrane components takes place in the acidic compartments of a cell, the endosomes and lysosomes. Sites of lipid degradation are intralysosomal membranes that are formed in endosomes, where the lipid composition is adjusted for degradation. Cholesterol is sorted out of the inner membranes, their content in bis(monoacylglycero)phosphate increases, and, most likely, sphingomyelin is degraded to ceramide. Together with endosomal and lysosomal lipid-binding proteins, the Niemann-Pick disease, type C2-protein, the GM2-activator, and the saposins sap-A, -B, -C, and -D, a suitable membrane lipid composition is required for degradation of complex lipids by hydrolytic enzymes. Copyright 2009 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  17. Comparative analysis of membrane lipids in psychrophilic and mesophilic freshwater dinoflagellates

    Directory of Open Access Journals (Sweden)

    Andrea eAnesi

    2016-04-01

    Full Text Available Here we report the lipid profiles of ten dinoflagellate species originating from different freshwater habitats and grown at 4, 13 or 20°C akin to their natural occurrence. Lipids were determined by High Performance Liquid Chromatography-ElectroSpray Ionization-Mass Spectrometry in positive and negative ion modes. Besides the well-studied monogalactosyldiacylglycerol (MGDG and digalactosyldiacylglycerol (DGDG lipids, our study revealed the presence of intact molecular lipid species of trigalactosyldiacylglycerols (TGDG, betaine diacylglyceryl-carboxyhydroxymethylcholine (DGCC, sulfolipid sulfoquinovosyldiacylglycerols (SQDG and phospholipids, in particular phosphatidylcholine (PC, phosphatidylethanolamine (PE and phosphatidylglycerol (PG.In multivariate ordination, the freshwater dinoflagellates studied could be distinguished into two groups based on their lipid profiles. Peridinium aciculiferum, Borghiella dodgei, B. tenuissima and Tovellia coronata belonged to group 1 while Ceratium cornutum, Gymnodinium palustre, Jadwigia applanata, P. cinctum, P. willei and P. gatunense belonged to group 2. Indicator species analysis evidenced that group 1 was characterized by 36:9 MGDG and 36:9 DGDG and group 2 by 38:9 and 38:10 MGDG, 38:9 and 38:10 DGDG and 34:1 SQDG. We suggest that the grouping of dinoflagellates indicated their range of temperature tolerance. Furthermore, non-thylakoid lipids were linked to dinoflagellate phylogeny based on the large ribosomal sub-unit (28S LSU rather than their temperature tolerance. Thus certain lipids better reflected habitat adaptation while other lipids better reflected genetic diversity.

  18. Parenteral lipid administration to very-low-birth-weight infants-early introduction of lipids and use of new lipid emulsions: a systematic review and meta-analysis

    NARCIS (Netherlands)

    Vlaardingerbroek, Hester; Veldhorst, Margriet A. B.; Spronk, Sandra; van den Akker, Chris H. P.; van Goudoever, Johannes B.

    2012-01-01

    Background: The use of intravenous lipid emulsions in preterm infants has been limited by concerns regarding impaired lipid tolerance. As a result, the time of initiation of parenteral lipid infusion to very-low-birth-weight (VLBW) infants varies widely among different neonatal intensive care units.

  19. Apolipoprotein M in lipid metabolism and cardiometabolic diseases

    DEFF Research Database (Denmark)

    Borup, Anna; Christensen, Pernille Meyer; Nielsen, Lars B.

    2015-01-01

    : The apoM/S1P axis and its implications in atherosclerosis and lipid metabolism have been thoroughly studied. Owing to the discovery of the apoM/S1P axis, the scope of apoM research has broadened. ApoM and S1P have been implicated in lipid metabolism, that is by modulating HDL particles. Also......PURPOSE: This review will address recent findings on apolipoprotein M (apoM) and its ligand sphingosine-1-phosphate (S1P) in lipid metabolism and inflammatory diseases. RECENT FINDINGS: ApoM's likely role(s) in health and disease has become more diverse after the discovery that apoM functions...... as a chaperone for S1P. Hence, apoM has recently been implicated in lipid metabolism, diabetes and rheumatoid arthritis through in-vivo, in-vitro and genetic association studies. It remains to be established to which degree such associations with apoM can be attributed to its ability to bind S1P. SUMMARY...

  20. SANS study of the unilamellar DMPC vesicles. The fluctuation model of lipid bilayer

    International Nuclear Information System (INIS)

    Kiselev, M.A.; Zemlyanaya, E.V.; Vinod, A.

    2003-01-01

    On the basis of the separated form-factors model, parameters of the polydispersed unilamellar DMPC vesicle population are analyzed. The neutron scattering length density across the membrane is simulated on the basis of fluctuated model of lipid bilayer. The hydration of vesicle is described by sigmoid distribution function of the water molecules. The results of fitting of the experimental data obtained at the small angle spectrometer SANS-I, PSI (Switzerland) are: average vesicle radius 272±0.4 Armstrong, polydispersity of the radius 27 %, membrane thickness 50.6± Armstrong, thickness of hydrocarbon chain region 21.4±2.8 Armstrong, number of water molecules located per lipid molecule 13±1, and DMPC surface area 59±2 Armstrong 2 . The calculated water distribution function across the bilayer directly explains why lipid membrane is easy penetrated by water molecules