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Sample records for channels inhibits high-fat

  1. Antagonism of T-type calcium channels inhibits high-fat diet–induced weight gain in mice

    OpenAIRE

    Uebele, Victor N.; Gotter, Anthony L.; Nuss, Cindy E.; Kraus, Richard L.; Doran, Scott M.; Garson, Susan L.; Reiss, Duane R.; Li, Yuxing; Barrow, James C.; Reger, Thomas S.; Yang, Zhi-Qiang; Ballard, Jeanine E.; Tang, Cuyue; Metzger, Joseph M.; Wang, Sheng-Ping

    2009-01-01

    The epidemics of obesity and metabolic disorders have well-recognized health and economic burdens. Pharmacologic treatments for these diseases remain unsatisfactory with respect to both efficacy and side-effect profiles. Here, we have identified a potential central role for T-type calcium channels in regulating body weight maintenance and sleep. Previously, it was shown that mice lacking CaV3.1 T-type calcium channels have altered sleep/wake activity. We found that these mice were also resist...

  2. Glucocorticoids inhibited hypothalamic target of rapamycin in high fat diet-fed chicks.

    Science.gov (United States)

    Liu, L; Wang, X; Jiao, H; Zhao, J; Lin, H

    2015-09-01

    The present study was conducted with broiler chicks exposed to dexamethasone (DEX) to explore its effects on hypothalamic target of rapamycin (TOR) signaling and regulating appetite in diets containing different energy levels. At 5 d age, 48 chicks were divided into one of 4 groups: high-fat diet (HFD) or low-fat diet (LFD) and intracerebroventricular (ICV) injected with either dexamethasone (DEX; 4 μg/2 μL) or saline at 10 d age. The results showed that DEX significantly inhibited gene expression of cocaine- and amphetamine-regulated transcripts (CART), melanocortin receptor 4 (MC4R), and corticotropin-releasing hormone (CRH), and inhibited the protein level of the phospho-TOR compared with the control in HFD-fed chicks (P0.05). After DEX treatment, hypothalamic agouti-related peptide levels were decreased significantly in HFD-fed chicks (P0.05). Compared to the control, DEX-treated chicks did not present any significant changes in neuropeptide Y gene expression with either HFD or LFD (P>0.05), but pro-opiomelanocortin levels were depressed by ICV DEX treatment with both diets (Pgene expression of CART, CRH, and MC4R in HFD-fed chicks, suggesting that the regulatory network formed by these genes is associated with the appetite control during stress. The TOR pathway may be involved in the regulation of GC on appetite-related genes. PMID:26188033

  3. TRPV1 Channels and Gastric Vagal Afferent Signalling in Lean and High Fat Diet Induced Obese Mice

    OpenAIRE

    Kentish, Stephen J.; Frisby, Claudine L.; Kritas, Stamatiki; Hui LI; Hatzinikolas, George; O’Donnell, Tracey A.; Wittert, Gary A; Page, Amanda J

    2015-01-01

    Aim Within the gastrointestinal tract vagal afferents play a role in control of food intake and satiety signalling. Activation of mechanosensitive gastric vagal afferents induces satiety. However, gastric vagal afferent responses to mechanical stretch are reduced in high fat diet mice. Transient receptor potential vanilloid 1 channels (TRPV1) are expressed in vagal afferents and knockout of TRPV1 reduces gastro-oesophageal vagal afferent responses to stretch. We aimed to determine the role of...

  4. High-fat feeding inhibits exercise-induced increase in mitochondrial respiratory flux in skeletal muscle

    DEFF Research Database (Denmark)

    Skovbro, Mette; Boushel, Robert Christopher; Hansen, Christina Neigaard;

    2011-01-01

    ) and intramyocellular triacylglycerol content did not change with the intervention in either group. Indexes of mitochondrial density were similar across the groups and intervention. Mitochondrial respiratory rates, measured in permeabilized muscle fibers, showed a 31 ± 11 and 26 ± 9% exercise-induced increase (P ...-62%) were seen in HFD and ND, but only in HFD was an elevated (P respiratory rate seen at recovery. With HFD complex I and IV protein expression decreased (P ... and in exercise-induced mitochondrial substrate oxidation rates, with the effects being present hours after the exercise. The effect of HFD is present even without effects on insulin sensitivity and intramyocellular lipid accumulation. An isocaloric high-fat diet does not cause insulin resistance....

  5. Prenatal nicotine exposure enhances Cx43 and Panx1 unopposed channel activity in brain cells of adult offspring mice fed a high-fat/cholesterol diet

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    Juan Andrés Orellana

    2014-12-01

    Full Text Available Nicotine, the most important neuroteratogen of tobacco smoke, can reproduce brain and cognitive disturbances per se when administered prenatally. However, it is still unknown if paracrine signaling among brain cells participates in prenatal nicotine-induced brain impairment of adult offspring. Paracrine signaling is partly mediated by unopposed channels formed by connexins (hemichannels and pannexins serving as aqueous pores permeable to ions and small signaling molecules, allowing exchange between the intra- and extracellular milieus. Our aim was to address whether prenatal nicotine exposure changes the activity of those channels in adult mice offspring under control conditions or subjected to a second challenge during young ages: high-fat/cholesterol (HFC diet. To induce prenatal exposure to nicotine, osmotic minipumps were implanted in CF1 pregnant mice at gestational day 5 to deliver nicotine bitartrate or saline (control solutions. After weaning, offspring of nicotine-treated or untreated pregnant mice were fed ad libitum with chow or HFC diets for 8 weeks. The functional state of Cx43 and Panx1 unopposed channels was evaluated by dye uptake experiments in hippocampal slices from 11-week-old mice. We found that prenatal nicotine increased the opening of Cx43 hemichannels in astrocytes, and Panx1 channels in microglia and neurons only if offspring mice were fed with HFC diet. Blockade of iNOS, COX2 and EP1, P2X7 and NMDA receptors, showed differential inhibition of prenatal nicotine-induced channel opening in glial cells and neurons. Importantly, inhibition of the above mentioned enzymes and receptors, or blockade of Cx43 and Panx1 unopposed channels greatly reduced ATP and glutamate release from hippocampal slices of prenatally nicotine-exposed offspring. We propose that unregulated gliotransmitter release through Cx43 and Panx1 unopposed channels may participate in brain alterations observed in offspring of mothers exposed to tobacco smoke

  6. Macrophage migration inhibitory factor inhibition is deleterious for high-fat diet-induced cardiac dysfunction.

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    Aurore Palud

    Full Text Available AIMS: Development of metabolic syndrome is associated with impaired cardiac performance, mitochondrial dysfunction and pro-inflammatory cytokine increase, such as the macrophage migration inhibitory factor MIF. Depending on conditions, MIF may exert both beneficial and deleterious effects on the myocardium. Therefore, we tested whether pharmacological inhibition of MIF prevented or worsened metabolic syndrome-induced myocardial dysfunction. METHODS AND RESULTS: C57BL/6J mice were fed for ten weeks with 60% fat-enriched diet (HFD or normal diet (ND. MIF inhibition was obtained by injecting mice twice a week with ISO-1, for three consecutive weeks. Then, triglycerides, cholesterol, fat mass, glucose intolerance, insulin resistance, ex vivo cardiac contractility, animal energetic substrate utilization assessed by indirect calorimetry and mitochondrial respiration and biogenesis were evaluated. HFD led to fat mass increase, dyslipidemia, glucose intolerance and insulin resistance. ISO-1 did not alter these parameters. However, MIF inhibition was responsible for HFD-induced cardiac dysfunction worsening. Mouse capacity to increase oxygen consumption in response to exercise was reduced in HFD compared to ND, and further diminished in ISO-1-treated HFD group. Mitochondrial respiration was reduced in HFD mice, treated or not with ISO-1. Compared to ND, mitochondrial biogenesis signaling was upregulated in the HFD as demonstrated by mitochondrial DNA amount and PGC-1α expression. However, this increase in biogenesis was blocked by ISO-1 treatment. CONCLUSION: MIF inhibition achieved by ISO-1 was responsible for a reduction in HFD-induced mitochondrial biogenesis signaling that could explain majored cardiac dysfunction observed in HFD mice treated with MIF inhibitor.

  7. Arctigenin Inhibits Adipogenesis by Inducing AMPK Activation and Reduces Weight Gain in High-Fat Diet-Induced Obese Mice.

    Science.gov (United States)

    Han, Yo-Han; Kee, Ji-Ye; Park, Jinbong; Kim, Hye-Lin; Jeong, Mi-Young; Kim, Dae-Seung; Jeon, Yong-Deok; Jung, Yunu; Youn, Dong-Hyun; Kang, JongWook; So, Hong-Seob; Park, Raekil; Lee, Jong-Hyun; Shin, Soyoung; Kim, Su-Jin; Um, Jae-Young; Hong, Seung-Heon

    2016-09-01

    Although arctigenin (ARC) has been reported to have some pharmacological effects such as anti-inflammation, anti-cancer, and antioxidant, there have been no reports on the anti-obesity effect of ARC. The aim of this study is to investigate whether ARC has an anti-obesity effect and mediates the AMP-activated protein kinase (AMPK) pathway. We investigated the anti-adipogenic effect of ARC using 3T3-L1 pre-adipocytes and human adipose tissue-derived mesenchymal stem cells (hAMSCs). In high-fat diet (HFD)-induced obese mice, whether ARC can inhibit weight gain was investigated. We found that ARC reduced weight gain, fat pad weight, and triglycerides in HFD-induced obese mice. ARC also inhibited the expression of peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha (C/EBPα) in in vitro and in vivo. Furthermore, ARC induced the AMPK activation resulting in down-modulation of adipogenesis-related factors including PPARγ, C/EBPα, fatty acid synthase, adipocyte fatty acid-binding protein, and lipoprotein lipase. This study demonstrates that ARC can reduce key adipogenic factors by activating the AMPK in vitro and in vivo and suggests a therapeutic implication of ARC for obesity treatment. J. Cell. Biochem. 117: 2067-2077, 2016. © 2016 Wiley Periodicals, Inc. PMID:26852013

  8. Inhibition of fetal bone development through epigenetic down- regulation of HoxA10 in obese rats fed high fat diet

    Science.gov (United States)

    Epidemiological studies show that maternal obesity during intrauterine and early postnatal life increases the risk of low bone mass and fracture later in life. Here, we show that bone development is inhibited in GED 18.5 embryos from rat dams made obese by feeding a high fat diet (HFD). Moreover, fe...

  9. Fenugreek Seed Extract Inhibit Fat Accumulation and Ameliorates Dyslipidemia in High Fat Diet-Induced Obese Rats

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    Parveen Kumar

    2014-01-01

    Full Text Available This study investigated the inhibitory effect of aqueous extract of Trigonella foenum-graecum seeds (AqE-TFG on fat accumulation and dyslipidemia in high fat diet- (HFD- induced obese rats. Female Wistar rats were fed with HFD ad libitum, and the rats on HFD were treated orally with AqE-TFG or orlistat ((HFD for 28 days + AqE-TFG (0.5 and 1.0 g/kg or orlistat (10 mg/kg from day 8 to 28, respectively. Treatment with AqE-TFG produced significant reduction in body weight gain, body mass index (BMI, white adipose tissue (WAT weights, blood glucose, serum insulin, lipids, leptin, lipase, and apolipoprotein-B levels and elevation in adiponectin levels. AqE-TFG improved serum aspartate amino transferase (AST, alanine amino transferase (ALT, and lactate dehydrogenase (LDH levels. AqE-TFG treatment reduced the hepatic and cardiac thiobarbituric acid reactive substances (TBARS and elevated the antioxidant enzyme (glutathione (GSH, superoxide dismutase (SOD, and catalase (CAT levels. In addition, liver and uterine WAT lipogenic enzyme (fatty acid synthetase (FAS and glucose-6-phosphate dehydrogenase (G6PD activities were restored towards normal levels. These findings demonstrated the preventive effect of AqE-TFG on fat accumulation and dyslipidemia, due to inhibition of impaired lipid digestion and absorption, in addition to improvement in glucose and lipid metabolism, enhancement of insulin sensitivity, increased antioxidant defense, and downregulation of lipogenic enzymes.

  10. Fenofibrate inhibits adipocyte hypertrophy and insulin resistance by activating adipose PPARα in high fat diet-induced obese mice

    OpenAIRE

    Jeong, Sunhyo; Yoon, Michung

    2009-01-01

    Peroxisome proliferator-activated receptor α (PPARα) activation in rodents is thought to improve insulin sensitivity by decreasing ectopic lipids in non-adipose tissues. Fenofibrate, a lipid-modifying agent that acts as a PPARα agonist, may prevent adipocyte hypertrophy and insulin resistance by increasing intracellular lipolysis from adipose tissue. Consistent with this hypothesis, fenofibrate decreased visceral fat mass and adipocyte size in high fat diet-fed obese mice, and concomitantly i...

  11. Buddleja officinalis Maximowicz Extract Inhibits Lipid Accumulation on Adipocyte Differentiation in 3T3-L1 Cells and High-Fat Mice

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    Jin-Kyu Kim

    2012-07-01

    Full Text Available Obesity is a global health problem. It is also known to be a risk factor for the development of metabolic disorders, type 2 diabetes, systemic hypertension, cardiovascular disease, dyslipidemia, and atherosclerosis. In this study, we elucidated that Buddleja officinalis Maximowicz extract significantly inhibited lipid accumulation during 3T3-L1 adipocyte differentiation. Furthermore, Buddleja officinalis Maximowicz extract reduced the body weight gain induced through feeding a high-fat diet to C57BL/6 mice. The treatment of Buddleja officinalis Maximowicz extract significantly reduced the adipose tissue weight to 2.7/100 g of body weight in high-fat mice. When their adipose tissue morphology was investigated for histochemical staining, the distribution of cell size in the high-fat diet groups was hypertrophied compared with those from Buddleja officinalis Maximowicz extract-treated mice. In addition, in Buddleja officinalis Maximowicz extract-treated mice, a significant reduction of serum triglyceride and T-cholesterol was observed at to 21% and 17%, respectively. The discovery of bioactive compounds from diet or dietary supplementation is one of possible ways to control obesity and to prevent or reduce the risks of various obesity-related diseases. These results support that Buddleja officinalis Maximowicz extract is expected to create the therapeutic interest with respect to the treatment of obesity.

  12. Rubus crataegifolius Bunge regulates adipogenesis through Akt and inhibits high-fat diet-induced obesity in rats

    OpenAIRE

    Jung, Min-Sup; Lee, Soo-Jung; Song, Yuno; Jang, Sun-Hee; Min, Wongi; Won, Chung-Kil; Kim, Hong-Duck; Kim, Tae Hoon; Cho, Jae-Hyeon

    2016-01-01

    Background Obesity is one of the greatest public health problems and major risk factors for serious metabolic diseases and significantly increases the risk of premature death. The aim of this study was to determine the inhibitory effects of Rubus crataegifolius Bunge (RCB) on adipocyte differentiation in 3 T3-L1 cells and its anti-obesity properties in high fat diet (HFD)-induced obese rats. Methods 3 T3-L1 adipocytes and HFD-induced obese rats were treated with RCB, and its effect on gene ex...

  13. Surgical removal of the parametrial fat pads stimulates apoptosis and inhibits UVB-induced carcinogenesis in mice fed a high-fat diet

    OpenAIRE

    Lu, Yao-Ping; Lou, You-Rong; Bernard, Jamie J.; Peng, Qing-Yun; Li, Tao; Lin, Yong; Shih, Weichung Joe; Nghiem, Paul; Shapses, Sue; Wagner, George C.; Conney, Allan H.

    2012-01-01

    Removal of the parametrial fat pads (partial lipectomy) from female SKH-1 mice fed a high-fat diet inhibited UVB-induced carcinogenesis, but this was not observed in mice fed a low-fat chow diet. Partial lipectomy in high-fat–fed mice decreased the number of keratoacanthomas and squamous cell carcinomas per mouse by 76 and 79%, respectively, compared with sham-operated control mice irradiated with UVB for 33 wk. Immunohistochemical analysis indicated that partial lipectomy increased caspase 3...

  14. Chrysobalanus icaco L. Leaves Normalizes Insulin Sensitivity and Blood Glucose and Inhibits Weight Gain in High-Fat Diet-Induced Obese Mice.

    Science.gov (United States)

    White, Pollyanna A S; Araújo, Jessica M D; Cercato, Luana M; Souza, Lucas A; Barbosa, Ana Paula Oliveira; Quintans-Junior, Lucindo José; Machado, Ubiratan F; Camargo, Enilton A; Brito, Luciana C; Santos, Marcio Roberto V

    2016-02-01

    Chrysobalanus icaco L. is a medicinal plant present in the Brazilian coastline and known for its hypoglicemic and antioxidant properties. Here, we assessed the beneficial metabolic effects of the aqueous extract of C. icaco (AECI) leaves in diet-induced obese mice. Swiss mice were fed standard chow (SC used as controls) or high-fat diet (HFD) to induce obesity. After 10 weeks, mice on each diet were divided into two groups with one group used as control while the other group treated with AECI for 4 weeks resulting in four groups of mice: SC; SC treated with AECI (SC + AECI); HFD; and HFD treated with AECI (HFD + AECI). AECI was administered drinking water at about 200 mg/kg. AECI was able to normalize insulin (13,682 ± 1090 vs. 9828 ± 485 AU, P < .05) and fasting blood glucose (192.8 ± 14.2 vs. 132.3 ± 6.4 mg/dL, P < .05) and inhibit weight gain (39 ± 5.7%) and fat storage in liver (72.60 ± 3.83%, P < .0001), despite the high-fat intake. These findings reinforce the use of AECI in hyperglycemia and highlight the potential extract's effect in preventing weight gain and fat accumulation in liver of diet-induced obese mice. PMID:26854845

  15. Carnitine palmitoyl transferase-I inhibition is not associated with cardiac hypertrophy in rats fed a high fat diet

    Science.gov (United States)

    Cardiac lipotoxicity is characterized by hypertrophy and contractile dysfunction and can be triggered by impaired mitochondrial fatty acid oxidation and lipid accumulation. The present study investigated the effect of dietary fatty acid intake alone and in combination with inhibition of mitochondria...

  16. Oral treatment with γ-aminobutyric acid improves glucose tolerance and insulin sensitivity by inhibiting inflammation in high fat diet-fed mice.

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    Jide Tian

    Full Text Available Adipocyte and β-cell dysfunction and macrophage-related chronic inflammation are critical for the development of obesity-related insulin resistance and type 2 diabetes mellitus (T2DM, which can be negatively regulated by Tregs. Our previous studies and those of others have shown that activation of γ-aminobutyric acid (GABA receptors inhibits inflammation in mice. However, whether GABA could modulate high fat diet (HFD-induced obesity, glucose intolerance and insulin resistance has not been explored. Here, we show that although oral treatment with GABA does not affect water and food consumption it inhibits the HFD-induced gain in body weights in C57BL/6 mice. Furthermore, oral treatment with GABA significantly reduced the concentrations of fasting blood glucose, and improved glucose tolerance and insulin sensitivity in the HFD-fed mice. More importantly, after the onset of obesity and T2DM, oral treatment with GABA inhibited the continual HFD-induced gain in body weights, reduced the concentrations of fasting blood glucose and improved glucose tolerance and insulin sensitivity in mice. In addition, oral treatment with GABA reduced the epididymal fat mass, adipocyte size, and the frequency of macrophage infiltrates in the adipose tissues of HFD-fed mice. Notably, oral treatment with GABA significantly increased the frequency of CD4(+Foxp3(+ Tregs in mice. Collectively, our data indicated that activation of peripheral GABA receptors inhibited the HFD-induced glucose intolerance, insulin resistance, and obesity by inhibiting obesity-related inflammation and up-regulating Treg responses in vivo. Given that GABA is safe for human consumption, activators of GABA receptors may be valuable for the prevention of obesity and intervention of T2DM in the clinic.

  17. Monascus pilosus-fermented black soybean inhibits lipid accumulation in adipocytes and in high-fat diet-induced obese mice

    Institute of Scientific and Technical Information of China (English)

    Young-Sil Lee; Bong-Keun Choi; Hae Jin Lee; Dong-Ryung Lee; Jinhua Cheng; Won-Keun Lee; Seung Hwan Yang; Joo-Won Suh

    2015-01-01

    Objective: To explore the anti-obesity effects and the mechanism of action of Monascus pilosus (M. pilosus)-fermented black soybean (MFBS) extracts (MFBSE) and MFBS powders (MFBSP) in adipocytes and high-fat diet (HFD)-induced obese mice, respectively. Methods:Black soybean was fermented with M. pilosus, and the main constituents in MFBS were analyzed by HPLC analysis. In vitro, MFBSE were examined for anti-adipogenic effects using Oil-Red O staining. In vivo, mice were fed a normal-fat diet (NFD) control, HFD control or HFD containing 1 g/kg MFBSP for 12 weeks, and then body weight gain and tissues weight measured. Real-time PCR and western blot assay were used to determine the mechanism of anti-adipogenic effects. Results: MFBSE inhibited lipid accumulation in 3T3-L1 adipocytes without exerting cell cytotoxicity. MFBSP treatment in HFD-fed mice significantly decreased the body weight gain compared with the HFD control mice. MFBSE and MFBSP treatment resulted in significantly lower mRNA levels of adipogenesis-related genes, such as peroxisome proliferator-activated receptor γ (PPARγ), fatty acid-binding protein 4 (FABP4), and fatty acid synthase (FAS), in adipocytes and in white adipose tissue (WAT) of HFD-induced obese mice. Conclusions: These results suggest that the anti-obesity effects of MFBS are elicited by regulating the expression of adipogenesis-related genes in adipocytes and WAT of HFD-induced obese mice.

  18. MGAT2 deficiency ameliorates high-fat diet-induced obesity and insulin resistance by inhibiting intestinal fat absorption in mice

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    Tsuchida Takuma

    2012-06-01

    Full Text Available Abstract Background Resynthesis of triglycerides in enterocytes of the small intestine plays a critical role in the absorption of dietary fat. Acyl-CoA:monoacylglycerol acyltransferase-2 (MGAT2 is highly expressed in the small intestine and catalyzes the synthesis of diacylglycerol from monoacylglycerol and acyl-CoA. To determine the physiological importance of MGAT2 in metabolic disorders and lipid metabolism in the small intestine, we constructed and analyzed Mgat2-deficient mice. Results In oral fat tolerance test (OFTT, Mgat2-deficient mice absorbed less fat into the circulation. When maintained on a high-fat diet (HFD, Mgat2-deficient mice were protected from HFD-induced obesity and insulin resistance. Heterozygote (Mgat2+/− mice had an intermediate phenotype between Mgat2+/+ and Mgat2−/− and were partially protected from metabolic disorders. Despite of a decrease in fat absorption in the Mgat2-deficient mice, lipid levels in the feces and small intestine were comparable among the genotypes. Oxygen consumption was increased in the Mgat2-deficient mice when maintained on an HFD. A prominent upregulation of the genes involved in fatty acid oxidation was observed in the duodenum but not in the liver of the Mgat2-deficient mice. Conclusion These results suggest that MGAT2 has a pivotal role in lipid metabolism in the small intestine, and the inhibition of MGAT2 activity may be a promising strategy for the treatment of obesity-related metabolic disorders.

  19. Monascus pilosus-fermented black soybean inhibits lipid accumulation in adipocytes and in high-fat diet-induced obese mice

    Institute of Scientific and Technical Information of China (English)

    Young-Sil; Lee; Bong-Keun; Choi; Hae; Jin; Lee; Dong-Ryung; Lee; Jinhua; Cheng; Won-Keun; Lee; Seung; Hwan; Yang; Joo-Won; Suh

    2015-01-01

    Objective:To explore the anti-obesity effects and the mechanism of action of Monascus pilosus(M.pilosus)-fermented black soybean(MFBS)extracts(MFBSE)and MFBS powders(MFBSP)in adipocytes and high-fat diet(HFD)-induced obese mice,respectively.Methods:Black soybean was fermented with M.pilosus,and the main constituents in MFBS were analyzed by HPLC analysis.In vitro,MFBSE were examined for anti-adipogenic effects using Oil-Red O staining.In vivo,mice were fed a normal-fat diet(NFD)control,HFD control or HFD containing 1 g/kg MFBSP for 12 weeks,and then body weight gain and tissues weight measured.Real-time PCR and western blot assay were used to determine the mechanism of anti-adipogenic effects.Results:MFBSE inhibited lipid accumulation in 3T3-L1 adipocytes without exerting cell cytotoxicity.MFBSP treatment in HFD-fed mice significantly decreased the body weight gain compared with the HFD control mice.MFBSE and MFBSP treatment resulted in significantly lower mRNA levels of adipogenesis-related genes,such as peroxisome proliferator-activated receptorγ(PPARγ),fatty acid-binding protein 4(FABP4),and fatty acid synthase(FAS),in adipocytes and in white adipose tissue(WAT)of HFD-induced obese mice.Conclusions:These results suggest that the anti-obesity effects of MFBS are elicited by regulating the expression of adipogenesis-related genes in adipocytes and WAT of HFDinduced obese mice.

  20. Multi-Strain Probiotics Inhibit Cardiac Myopathies and Autophagy to Prevent Heart Injury in High-Fat Diet-Fed Rats

    Science.gov (United States)

    Lai, Chao-Hung; Tsai, Cheng-Chih; Kuo, Wei-Wen; Ho, Tsung-Jung; Day, Cecilia-Hsuan; Pai, Pei-ying; Chung, Li-Chin; Huang, Chun-Chih; Wang, Hsueh-Fang; Liao, Po-Hsiang; Huang, Chih-Yang

    2016-01-01

    High-fat diets induce obesity, leading to cardiomyocyte fibrosis and autophagy imbalance. In addition, no previous studies have indicated that probiotics have potential health effects associated with cardiac fibrosis and autophagy in obese rats. This study investigates the effects of probiotics on high-fat (HF) diet-induced obesity and cardiac fibrosis and autophagy in rat hearts. Eight-week-old male Wistar rats were separated randomly into five equally sized experimental groups: Normal diet (control) and high-fat (HF) diet groups and groups fed a high-fat diet supplemented with low (HL), medium (HM) or high (HH) doses of multi-strain probiotic powders. These experiments were designed for an 8-week trial period. The myocardial architecture of the left ventricle was evaluated using Masson's trichrome staining and immunohistochemistry staining. Key probiotics-related pathway molecules were analyzed using western blotting. Abnormal myocardial architecture and enlarged interstitial spaces were observed in HF hearts. These interstitial spaces were significantly decreased in groups provided with multi-strain probiotics compared with HF hearts. Western blot analysis demonstrated that key components of the TGF/MMP2/MMP9 fibrosis pathways and ERK5/uPA/ANP cardiac hypertrophy pathways were significantly suppressed in probiotic groups compared to the HF group. Autophagy balance is very important in cardiomyocytes. In this study, we observed that the beclin-1/LC3B/Atg7 autophagy pathway in HF was increased after probiotic supplementation was significantly decreased. Together, these results suggest that oral administration of probiotics may attenuate cardiomyocyte fibrosis and cardiac hypertrophy and the autophagy-signaling pathway in obese rats. PMID:27076784

  1. A Mineral-Rich Red Algae Extract Inhibits Polyp Formation and Inflammation in the Gastrointestinal Tract of Mice on a High-Fat Diet

    Science.gov (United States)

    Aslam, Muhammad Nadeem; Paruchuri, Tejaswi; Bhagavathula, Narasimharao; Varani, James

    2010-01-01

    The purpose of this study was to determine whether a mineral-rich extract derived from the red marine algae, Lithothamnion calcareum (Pallas), could be used as a dietary supplement for chemoprevention against colon polyp formation. Sixty C57bl/6 mice were divided into three groups based on diet. One group received a low-fat, rodent chow diet (AIN76A). The second group received a high-fat “Western style” diet (HFWD). The third group was fed the same HFWD with the mineral-rich extract included as a dietary supplement. Mice were maintained on the respective diets for 15 months. Autopsies were performed at the time of death or at the completion of the study. To summarize, the cumulative mortality rate was higher in mice on the HFWD during the 15 month period (55%) than in mice from the low-fat diet or the extract-supplemented high-fat diet groups (20% and 30%, respectively; p<0.05 with respect to both). Autopsies revealed colon polyps in 20% of the animals on the HFWD and none in animals of the other two groups (p<0.05). In addition to the grossly visible polyps, areas of hyperplasia in the colonic mucosa and inflammatory foci throughout the gastrointestinal tract were observed histologically in animals on the high-fat diet. Both were significantly reduced in animals on the low-fat diet and animals on the extract-supplemented HFWD. These data suggest that the mineral-rich algae extract may provide a novel approach to chemoprevention in the colon. PMID:20150219

  2. A Mineral-Rich Red Algae Extract Inhibits Polyp Formation and Inflammation in the Gastrointestinal Tract of Mice on a High-Fat Diet

    OpenAIRE

    Aslam, Muhammad Nadeem; Paruchuri, Tejaswi; Bhagavathula, Narasimharao; Varani, James

    2010-01-01

    The purpose of this study was to determine whether a mineral-rich extract derived from the red marine algae, Lithothamnion calcareum (Pallas), could be used as a dietary supplement for chemoprevention against colon polyp formation. Sixty C57bl/6 mice were divided into three groups based on diet. One group received a low-fat, rodent chow diet (AIN76A). The second group received a high-fat “Western style” diet (HFWD). The third group was fed the same HFWD with the mineral-rich extract included ...

  3. Sodium Channel Inhibiting Marine Toxins

    Science.gov (United States)

    Llewellyn, Lyndon E.

    Saxitoxin (STX), tetrodotoxin (TTX) and their many chemical relatives are part of our daily lives. From killing people who eat seafood containing these toxins, to being valuable research tools unveiling the invisible structures of their pharmacological receptor, their global impact is beyond measure. The pharmacological receptor for these toxins is the voltage-gated sodium channel which transports Na ions between the exterior to the interior of cells. The two structurally divergent families of STX and TTX analogues bind at the same location on these Na channels to stop the flow of ions. This can affect nerves, muscles and biological senses of most animals. It is through these and other toxins that we have developed much of our fundamental understanding of the Na channel and its part in generating action potentials in excitable cells.

  4. Offspring of mothers fed a high fat diet display hepatic cell cycle inhibition and associated changes in gene expression and DNA methylation.

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    Kevin J Dudley

    Full Text Available The association between an adverse early life environment and increased susceptibility to later-life metabolic disorders such as obesity, type 2 diabetes and cardiovascular disease is described by the developmental origins of health and disease hypothesis. Employing a rat model of maternal high fat (MHF nutrition, we recently reported that offspring born to MHF mothers are small at birth and develop a postnatal phenotype that closely resembles that of the human metabolic syndrome. Livers of offspring born to MHF mothers also display a fatty phenotype reflecting hepatic steatosis and characteristics of non-alcoholic fatty liver disease. In the present study we hypothesised that a MHF diet leads to altered regulation of liver development in offspring; a derangement that may be detectable during early postnatal life. Livers were collected at postnatal days 2 (P2 and 27 (P27 from male offspring of control and MHF mothers (n = 8 per group. Cell cycle dynamics, measured by flow cytometry, revealed significant G0/G1 arrest in the livers of P2 offspring born to MHF mothers, associated with an increased expression of the hepatic cell cycle inhibitor Cdkn1a. In P2 livers, Cdkn1a was hypomethylated at specific CpG dinucleotides and first exon in offspring of MHF mothers and was shown to correlate with a demonstrable increase in mRNA expression levels. These modifications at P2 preceded observable reductions in liver weight and liver∶brain weight ratio at P27, but there were no persistent changes in cell cycle dynamics or DNA methylation in MHF offspring at this time. Since Cdkn1a up-regulation has been associated with hepatocyte growth in pathologic states, our data may be suggestive of early hepatic dysfunction in neonates born to high fat fed mothers. It is likely that these offspring are predisposed to long-term hepatic dysfunction.

  5. Water-Soluble Chitosan Nanoparticles Inhibit Hypercholesterolemia Induced by Feeding a High-Fat Diet in Male Sprague-Dawley Rats

    International Nuclear Information System (INIS)

    Chitosan, a deacetylated product of chitin, has been demonstrated to lower cholesterol in humans and animals. However, chitosan is not fully soluble in water which would influence absorption in the human intestine. In addition, water-soluble chitosan (WSC) has higher reactivity compared to chitosan. The present study was designed to clarify the effects of WSC and water-soluble chitosan nanoparticles (WSC-NPs) on hypercholesterolemia induced by feeding a high-fat diet in male Sprague-Dawley rats. WSC-NPs were prepared by the ionic gelation method and the spray-drying technique. The nanoparticles were spherical in shape and had a smooth surface. The mean size of WSC-NPs was 650 nm variing from 500 to 800?nm. Results showed that WSC-NPs reduced the blood lipids and plasma viscosity significantly and increased the serum superoxide dismutase (SOD) activities significantly. This paper is the first report of the lipid-lowering effects of WSC-NPs suggesting that the WSC-NPs could be used for the treatment of hypercholesterolemia

  6. BL153 Partially Prevents High-Fat Diet Induced Liver Damage Probably via Inhibition of Lipid Accumulation, Inflammation, and Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Jian Wang

    2014-01-01

    Full Text Available The present study was to investigate whether a magnolia extract, named BL153, can prevent obesity-induced liver damage and identify the possible protective mechanism. To this end, obese mice were induced by feeding with high fat diet (HFD, 60% kcal as fat and the age-matched control mice were fed with control diet (10% kcal as fat for 6 months. Simultaneously these mice were treated with or without BL153 daily at 3 dose levels (2.5, 5, and 10 mg/kg by gavage. HFD feeding significantly increased the body weight and the liver weight. Administration of BL153 significantly reduced the liver weight but without effects on body weight. As a critical step of the development of NAFLD, hepatic fibrosis was induced in the mice fed with HFD, shown by upregulating the expression of connective tissue growth factor and transforming growth factor beta 1, which were significantly attenuated by BL153 in a dose-dependent manner. Mechanism study revealed that BL153 significantly suppressed HFD induced hepatic lipid accumulation and oxidative stress and slightly prevented liver inflammation. These results suggest that HFD induced fibrosis in the liver can be prevented partially by BL153, probably due to reduction of hepatic lipid accumulation, inflammation and oxidative stress.

  7. GLP-1 receptor activation inhibits VLDL production and reverses hepatic steatosis by decreasing hepatic lipogenesis in high-fat-fed APOE*3-Leiden mice.

    Directory of Open Access Journals (Sweden)

    Edwin T Parlevliet

    Full Text Available OBJECTIVE: In addition to improve glucose intolerance, recent studies suggest that glucagon-like peptide-1 (GLP-1 receptor agonism also decreases triglyceride (TG levels. The aim of this study was to evaluate the effect of GLP-1 receptor agonism on very-low-density lipoprotein (VLDL-TG production and liver TG metabolism. EXPERIMENTAL APPROACH: The GLP-1 peptide analogues CNTO3649 and exendin-4 were continuously administered subcutaneously to high fat diet-fed APOE*3-Leiden transgenic mice. After 4 weeks, hepatic VLDL production, lipid content, and expression profiles of selected genes involved in lipid metabolism were determined. RESULTS: CNTO3649 and exendin-4 reduced fasting plasma glucose (up to -30% and -28% respectively and insulin (-43% and -65% respectively. In addition, these agents reduced VLDL-TG production (-36% and -54% respectively and VLDL-apoB production (-36% and -43% respectively, indicating reduced production of VLDL particles rather than reduced lipidation of apoB. Moreover, they markedly decreased hepatic content of TG (-39% and -55% respectively, cholesterol (-30% and -55% respectively, and phospholipids (-23% and -36% respectively, accompanied by down-regulation of expression of genes involved in hepatic lipogenesis (Srebp-1c, Fasn, Dgat1 and apoB synthesis (Apob. CONCLUSION: GLP-1 receptor agonism reduces VLDL production and hepatic steatosis in addition to an improvement of glycemic control. These data suggest that GLP-receptor agonists could reduce hepatic steatosis and ameliorate dyslipidemia in patients with type 2 diabetes mellitus.

  8. Dietary aloe vera gel powder and extract inhibit azoxymethane- induced colorectal aberrant crypt foci in mice fed a high- fat diet.

    Science.gov (United States)

    Chihara, Takeshi; Shimpo, Kan; Kaneko, Takaaki; Beppu, Hidehiko; Higashiguchi, Takashi; Sonoda, Shigeru; Tanaka, Miyuki; Yamada, Muneo; Abe, Fumiaki

    2015-01-01

    Aloe vera gel exhibits protective effects against insulin resistance as well as lipid-lowering and anti-diabetic effects. The anti-diabetic compounds in this gel were identified as Aloe-sterols. Aloe vera gel extract (AVGE) containing Aloe-sterols has recently been produced using a new procedure. We previously reported that AVGE reduced large-sized intestinal polyps in Apc-deficient Min mice fed a high fat diet (HFD), suggesting that Aloe vera gel may protect against colorectal cancer. In the present study, we examined the effects of Aloe vera gel powder (AVGP) and AVGE on azoxymethane-induced colorectal preneoplastic aberrant crypt foci (ACF) in mice fed a HFD. Male C57BL/6J mice were given a normal diet (ND), HFD, HFD containing 0.5% carboxymethyl cellulose solution, which was used as a solvent for AVGE (HFDC), HFD containing 3% or 1% AVGP, and HFDC containing 0.0125% (H-) or 0.00375% (L-) AVGE. The number of ACF was significantly lower in mice given 3% AVGP and H-AVGE than in those given HFD or HFDC alone. Moreover, 3% AVGP, H-AVGE and L-AVGE significantly decreased the mean Ki-67 labeling index, assessed as a measure of cell proliferation in the colonic mucosa. In addition, hepatic phase II enzyme glutathione S-transferase mRNA levels were higher in the H-AVGE group than in the HFDC group. These results suggest that both AVGP and AVGE may have chemopreventive effects on colorectal carcinogenesis under the HFD condition. Furthermore, the concentration of Aloe-sterols was similar between 3% AVGP and H-AVGE, suggesting that Aloe-sterols were the main active ingredients in this experiment. PMID:25684508

  9. Theaflavin Synthesized in a Selective, Domino-Type, One-Pot Enzymatic Biotransformation Method with Camellia sinensis Cell Culture Inhibits Weight Gain and Fat Accumulation to High-Fat Diet-Induced Obese Mice.

    Science.gov (United States)

    Takemoto, Masumi; Takemoto, Hiroaki; Saijo, Ryoyasu

    2016-08-01

    The polyphenolic compound theaflavin, which is the main red pigment present in black tea, is reported to elicit various physiological effects. Because of the extremely low concentration of theaflavin present in black tea, its extraction from black tea leaves in quantities sufficient for use in medical studies has been difficult. We have developed a simple, inexpensive, selective, domino-type, one-pot enzymatic biotransformation method for the synthesis of theaflavin that is suitable for use in medical studies. Subsequent administration of this synthetic theaflavin to high-fat diet-induced obese mice inhibited both body weight gain and visceral fat accumulation, with no significant difference in the amount of faeces between the experimental and control mice. PMID:27237789

  10. The Protective Effect of Beraprost Sodium on Diabetic Nephropathy by Inhibiting Inflammation and p38 MAPK Signaling Pathway in High-Fat Diet/Streptozotocin-Induced Diabetic Rats

    Science.gov (United States)

    Peng, Li; Li, Jie; Xu, Yixing; Wang, Yangtian; Du, Hong; Shao, Jiaqing; Liu, Zhimin

    2016-01-01

    Background. p38 mitogen-activated protein kinase (MAPK) plays a crucial role in regulating signaling pathways implicated in inflammatory processes leading to diabetic nephropathy (DN). This study aimed to examine p38 MAPK activation in DN and determine whether beraprost sodium (BPS) ameliorates DN by inhibiting inflammation and p38 MAPK signaling pathway in diabetic rats. Methods. Forty male Sprague Dawley (SD) rats were randomly divided into the normal control group, type 2 diabetic group, and BPS treatment group. At the end of the 8-week experiment, we measured renal pathological changes and the activation of the p38 MAPK signaling pathway and inflammation. Result. After BPS treatment, renal function, 24-hour urine protein, lipid profiles, and blood glucose level were improved significantly; meanwhile, inflammation and the expression of p38 MAPK signaling pathway in the diabetic kidney were attenuated. Conclusions. BPS significantly prevented type 2 diabetes induced kidney injury characterized by renal dysfunction and pathological changes. The protective mechanisms are complicated but may be mainly attributed to the inhibition of the p38 MAPK signaling pathway and inflammation in the diabetic kidney.

  11. Astaxanthin reduces hepatic lipid accumulations in high-fat-fed C57BL/6J mice via activation of peroxisome proliferator-activated receptor (PPAR) alpha and inhibition of PPAR gamma and Akt.

    Science.gov (United States)

    Jia, Yaoyao; Wu, Chunyan; Kim, Jiyoung; Kim, Bobae; Lee, Sung-Joon

    2016-02-01

    We have previously reported that astaxanthin (AX), a dietary carotenoid, directly interacts with peroxisome proliferator-activated receptors PPARα and PPARγ, activating PPARα while inhibiting PPARγ, and thus reduces lipid accumulation in hepatocytes in vitro. To investigate the effects of AX in vivo, high-fat diet (HFD)-fed C57BL/6J mice were orally administered AX (6 or 30mg/kg body weight) or vehicle for 8weeks. AX significantly reduced the levels of triglyceride both in plasma and in liver compared with the control HFD mice. AX significantly improved liver histology and thus reduced both steatosis and inflammation scores of livers with hematoxylin and eosin staining. The number of inflammatory macrophages and Kupffer cells were reduced in livers by AX administration assessed with F4/80 staining. Hepatic PPARα-responsive genes involved in fatty acid uptake and β-oxidation were upregulated, whereas inflammatory genes were downregulated by AX administration. In vitro radiolabeled assays revealed that hepatic fatty acid oxidation was induced by AX administration, whereas fatty acid synthesis was not changed in hepatocytes. In mechanism studies, AX inhibited Akt activity and thus decreased SREBP1 phosphorylation and induced Insig-2a expression, both of which delayed nuclear translocation of SREBP1 and subsequent hepatic lipogenesis. Additionally, inhibition of the Akt-mTORC1 signaling axis by AX stimulated hepatic autophagy that could promote degradation of lipid droplets. These suggest that AX lowers hepatic lipid accumulation in HFD-fed mice via multiple mechanisms. In addition to the previously reported differential regulation of PPARα and PPARγ, inhibition of Akt activity and activation of hepatic autophagy reduced hepatic steatosis in mouse livers. PMID:26878778

  12. Inhibition of the Inflammasome NLRP3 by Arglabin Attenuates Inflammation, Protects Pancreatic β-Cells from Apoptosis, and Prevents Type 2 Diabetes Mellitus Development in ApoE2Ki Mice on a Chronic High-Fat Diet.

    Science.gov (United States)

    Abderrazak, Amna; El Hadri, Khadija; Bosc, Elodie; Blondeau, Bertrand; Slimane, Mohamed-Naceur; Büchele, Berthold; Simmet, Thomas; Couchie, Dominique; Rouis, Mustapha

    2016-06-01

    Intraperitoneal injection of arglabin (2.5 ng/g of body weight, twice daily, 13 weeks) into female human apolipoprotein E2 gene knock-in (ApoE2Ki) mice fed a high-fat Western-type diet (HFD) reduced plasma levels of glucose and insulin by ∼20.0% ± 3.5% and by 50.0% ± 2.0%, respectively, in comparison with vehicle-treated mice. Immunohistochemical analysis revealed the absence of active caspase-3 in islet sections from ApoE2Ki mice fed a HFD and treated with arglabin. In addition, arglabin reduced interleukin-1β (IL-1β) production in a concentration-dependent manner in Langerhans islets isolated from ApoE2Ki mice treated with lipopolysaccharide (LPS) and with cholesterol crystals. This inhibitory effect is specific for the inflammasome NOD-like receptor family, pyrin domain-containing 3 (NLRP3) because IL-1β production was abolished in Langerhans islets isolated from Nlrp3(-/-) mice. In the insulin-secreting INS-1 cells, arglabin inhibited, in a concentration-dependent manner, the maturation of pro-IL-1β into biologically active IL-1β probably through the inhibition of the maturation of procaspase-1 into active capsase-1. Moreover, arglabin reduced the susceptibility of INS-1 cells to apoptosis by increasing Bcl-2 levels. Similarly, autophagy activation by rapamycin decreased apoptosis susceptibility while autophagy inhibition by 3-methyladenin treatment promoted apoptosis. Arglabin further increased the expression of the autophagic markers Bcl2-interacting protein (Beclin-1) and microtubule-associated protein 1 light chain 3 II (LC3-II) in a concentration-dependent manner. Thus, arglabin reduces NLRP3-dependent inflammation as well as apoptosis in pancreatic β-cells in vivo and in the INS-1 cell line in vitro, whereas it increases autophagy in cultured INS-1 cells, indicating survival-promoting properties of the compound in these cells. Hence, arglabin may represent a new promising compound to treat inflammation and type 2 diabetes mellitus development

  13. High-fat intake induced by mu-opioid activation of the nucleus accumbens is inhibited by Y1R-blockade and MC3/4R-stimulation

    OpenAIRE

    Zheng, Huiyuan; Townsend, R. Leigh; Shin, Andrew; Patterson, Laurel M.; Phifer, Curtis B.; Berthoud, Hans-Rudolf

    2010-01-01

    Nucleus accumbens mu-opioid receptor activation can strongly stimulate intake of high-fat food in satiated rats, and one of the mechanisms involves activation of lateral hypothalamic orexin neurons and orexin receptor-1 signaling in the mesolimbic dopamine system. Here, we tested the potential contribution of NPY/Y1R and α-MSH/MC3/4R-signaling to accumbens-induced high-fat feeding. Prior administration of the selective Y1R antagonist 1229U91 or the MC3/4R agonist MTII into the lateral ventric...

  14. The Herbal Medicine KBH-1 Inhibits Fat Accumulation in 3T3-L1 Adipocytes and Reduces High Fat Diet-Induced Obesity through Regulation of the AMPK Pathway.

    Directory of Open Access Journals (Sweden)

    Ji-Hye Lee

    Full Text Available The aim of this study was to investigate whether a novel formulation of an herbal extract, KBH-1, has an inhibitory effect on obesity. To determine its anti-obesity effects and its underlying mechanism, we performed anti-obesity-related experiments in vitro and in vivo. 3T3-L1 preadipocytes were analyzed for lipid accumulation as well as the protein and gene expression of molecular targets involved in fatty acid synthesis. To determine whether KBH-1 oral administration results in a reduction in high-fat diet (HFD-induced obesity, we examined five groups (n = 9 of C57BL/6 mice as follows: 10% kcal fat diet-fed mice (ND, 60% kcal fat diet-fed mice (HFD, HFD-fed mice treated with orlistat (tetrahydrolipstatin, marketed under the trade name Xenical, HFD-fed mice treated with 150 mg/kg KBH-1 (KBH-1 150 and HFD-fed mice treated with 300 mg/kg KBH-1 (KBH-1 300. During adipogenesis of 3T3-L1 cells in vitro, KBH-1 significantly reduced lipid accumulation and down-regulated the expression of master adipogenic transcription factors, including CCAAT/enhancer binding protein (C/EBP β, C/EBP α and peroxisome proliferation-activity receptor (PPAR γ, which led to the suppression of the expression of several adipocyte-specific genes and proteins. KBH-1 also markedly phosphorylated the adenosine monophosphate-activated protein kinase (AMPK and acetyl-CoA carboxylase (ACC. In addition, KBH-1-induced the inhibition effect on lipid accumulation and AMPK-mediated signal activation were decreased by blocking AMPK phosphorylation using AMPK siRNA. Furthermore, daily oral administration of KBH-1 resulted in dose-dependent decreases in body weight, fat pad mass and fat tissue size without systemic toxicity. These results suggest that KBH-1 inhibits lipid accumulation by down-regulating the major transcription factors of the adipogenesis pathway by regulating the AMPK pathway in 3T3-L1 adipocytes and in mice with HFD-induced obesity. These results implicate KBH-1, a

  15. Antiarrhythmic Mechanisms of SK Channel Inhibition in the Rat Atrium

    DEFF Research Database (Denmark)

    Skibsbye, Lasse; Wang, Xiaodong; Axelsen, Lene Nygaard;

    2015-01-01

    period (ERP) and slowing the conduction velocity. We therefore aimed at elucidating these properties of SK channel inhibition and the underlying antiarrhythmic mechanisms by using; microelectrode action potential recordings and conduction velocity measurements in isolated rat atrium. Automated patch-clamping...... and two-electrode voltage-clamp was used to access INa and IK,ACh respectively. RESULTS: The SK channel inhibitor N-(pyridin-2-yl)-4-(pyridin-2-yl)thiazol-2-amine (ICA) exhibited antiarrhythmic effects. ICA prevented electrically induced runs of atrial fibrillation in the isolated right atrium and...... channel inhibition by ICA (10-30 µM) demonstrated prominent depression of other sodium channel-dependent parameters. ICA did not inhibit IK,ACh, but at concentrations above 10 µM ICA use-dependently inhibited INa. CONCLUSION: SK channel inhibition modulates multiple parameters of the action potential. It...

  16. NSAIDs acutely inhibit TRPC channels in freshly isolated rat glomeruli

    Energy Technology Data Exchange (ETDEWEB)

    Ilatovskaya, Daria V. [Department of Physiology, Medical College of Wisconsin, Milwaukee, WI (United States); Institute of Cytology RAS, St. Petersburg (Russian Federation); Levchenko, Vladislav; Ryan, Robert P.; Cowley, Allen W. [Department of Physiology, Medical College of Wisconsin, Milwaukee, WI (United States); Staruschenko, Alexander, E-mail: Staruschenko@mcw.edu [Department of Physiology, Medical College of Wisconsin, Milwaukee, WI (United States)

    2011-05-06

    Highlights: {yields} We have established a unique approach to search for physiologically relevant mechanisms of TRPC channels in podocytes. {yields} This study describes endogenous TRPC channels in the isolated decapsulated glomeruli preparation. {yields} We report for the first time that NSAIDs inhibit TRPC channels in podocytes. -- Abstract: Using a novel approach for analysis of TRPC channel activity, we report here that NSAIDs are involved into regulation of TRPC channels in the podocytes of the freshly isolated decapsulated glomeruli. Fluorescence and electron microscopy techniques confirmed the integrity of podocytes in the glomeruli. Western blotting showed that TRPC1, 3 and 6 are highly expressed in the glomeruli. Single-channel patch clamp analysis revealed cation currents with distinct TRPC properties. This is the first report describing single TRPC-like currents in glomerular podocytes. Furthermore, our data provide a novel mechanism of NSAIDs regulation of TRPC channels, which might be implicated in maintaining the glomerular filtration barrier.

  17. NSAIDs acutely inhibit TRPC channels in freshly isolated rat glomeruli

    International Nuclear Information System (INIS)

    Highlights: → We have established a unique approach to search for physiologically relevant mechanisms of TRPC channels in podocytes. → This study describes endogenous TRPC channels in the isolated decapsulated glomeruli preparation. → We report for the first time that NSAIDs inhibit TRPC channels in podocytes. -- Abstract: Using a novel approach for analysis of TRPC channel activity, we report here that NSAIDs are involved into regulation of TRPC channels in the podocytes of the freshly isolated decapsulated glomeruli. Fluorescence and electron microscopy techniques confirmed the integrity of podocytes in the glomeruli. Western blotting showed that TRPC1, 3 and 6 are highly expressed in the glomeruli. Single-channel patch clamp analysis revealed cation currents with distinct TRPC properties. This is the first report describing single TRPC-like currents in glomerular podocytes. Furthermore, our data provide a novel mechanism of NSAIDs regulation of TRPC channels, which might be implicated in maintaining the glomerular filtration barrier.

  18. Inhibition of Voltage-Gated Calcium Channels by RGK Proteins.

    Science.gov (United States)

    Buraei, Zafir; Yang, Jian

    2015-01-01

    Due to their essential biological roles, voltage-gated calcium channels (VGCCs) are regulated by a myriad of molecules and mechanisms. Fifteen years ago, RGK proteins were discovered to bind the VGCC β subunit (Cavβ) and potently inhibit high-voltage activated Ca(2+) channels. RGKs (Rad, Rem, Rem2 and Gem/Kir) are a family of monomeric small GTPases belonging to the superfamily of Ras GTPases. They exert dual inhibitory effects on VGCCs, decreasing surface expression and suppressing surface channels through immobilization of the voltage sensor or reduction of channel open probability. While Cavβ is required for all forms of RGK inhibition, not all inhibition is mediated by the RGK-Cavβ interaction. Some RGK proteins also interact directly with the pore-forming α1 subunit of some types of VGCCs (Cavα1). Importantly, RGK proteins tonically inhibit VGCCs in native cells, regulating cardiac and neural functions. This minireview summarizes the mechanisms, molecular determinants, and physiological impact of RGK inhibition of VGCCs. PMID:25966691

  19. SLO2 Channels Are Inhibited by All Divalent Cations That Activate SLO1 K+ Channels.

    Science.gov (United States)

    Budelli, Gonzalo; Sun, Qi; Ferreira, Juan; Butler, Alice; Santi, Celia M; Salkoff, Lawrence

    2016-04-01

    Two members of the family of high conductance K(+)channels SLO1 and SLO2 are both activated by intracellular cations. However, SLO1 is activated by Ca(2+)and other divalent cations, while SLO2 (Slack or SLO2.2 from rat) is activated by Na(+) Curiously though, we found that SLO2.2 is inhibited by all divalent cations that activate SLO1, with Zn(2+)being the most effective inhibitor with an IC50of ∼8 μmin contrast to Mg(2+), the least effective, with an IC50of ∼ 1.5 mm Our results suggest that divalent cations are not SLO2 pore blockers, but rather inhibit channel activity by an allosteric modification of channel gating. By site-directed mutagenesis we show that a histidine residue (His-347) downstream of S6 reduces inhibition by divalent cations. An analogous His residue present in some CNG channels is an inhibitory cation binding site. To investigate whether inhibition by divalent cations is conserved in an invertebrate SLO2 channel we cloned the SLO2 channel fromDrosophila(dSLO2) and compared its properties to those of rat SLO2.2. We found that, like rat SLO2.2, dSLO2 was also activated by Na(+)and inhibited by divalent cations. Inhibition of SLO2 channels in mammals andDrosophilaby divalent cations that have second messenger functions may reflect the physiological regulation of these channels by one or more of these ions. PMID:26823461

  20. Preventive effects of bitter melon (Momordica charantia) against insulin resistance and diabetes are associated with the inhibition of NF-κB and JNK pathways in high-fat-fed OLETF rats.

    Science.gov (United States)

    Yang, Soo Jin; Choi, Jung Mook; Park, Se Eun; Rhee, Eun Jung; Lee, Won Young; Oh, Ki Won; Park, Sung Woo; Park, Cheol-Young

    2015-03-01

    Bitter melon (BM; Momordica charantia) has been used as a treatment method for various diseases including cancer and diabetes. The objective of this study was to investigate whether BM has preventive effects against insulin resistance and diabetes and to identify the underlying mechanism by which BM ameliorates insulin resistance in obese and diabetic rats. The rats were separated into three groups as follows: (a) high-fat (HF) diet control, (b) HF diet and 1% BM and (c) HF diet and 3% BM. After 6 weeks of assigned treatments, body weight and food intake were not altered by BM administration. Bitter melon treatment significantly improved glucose tolerance and insulin sensitivity. The levels of proinflammatory cytokines were significantly down-regulated in liver, muscle and epididymal fats from BM-treated rats. The activation of nuclear factor-κB (NF-κB) in the liver and muscle was decreased by BM compared with HF controls. The 3% BM supplementation significantly increased the levels of phospho-insulin receptor substrate-1 (Tyr612) and phospho-Akt (Ser473). It also significantly decreased the levels of phospho-NF-κB (p65) (Ser536) and phospho-c-Jun N-terminal kinase (JNK) (Thr183/Tyr185) in liver, muscle and epididymal fats. The findings of this study indicate that BM exerted preventive effects against insulin resistance and diabetes through the modulation of NF-κB and JNK pathways. Therefore, BM may be useful in the prevention of insulin resistance and diabetes. PMID:25488547

  1. Low carb high fat : Passar det normalviktiga?

    OpenAIRE

    Malmgren, Evelina; Ingelsson, Frida; Ohlsson, Annica

    2012-01-01

    Low Carb High Fat (LCHF) ses som en striktare variant av GI eller Atkins och är en diet riktad framförallt till personer som lider av det metabola syndromet, där man utesluter i princip alla kolhydrater för att undvika blodsockerhöjningar. Överviktiga och diabetiker som testat denna diet har både fått bättre blodfetter, viktnedgång samt ett förbättrat blodsocker men samtidigt finns det många motsträvare – framförallt SNR (svenska näringsrekommendationer). Syftet med detta projekt var att visa...

  2. Curcumin inhibits activation of TRPM2 channels in rat hepatocytes.

    Science.gov (United States)

    Kheradpezhouh, E; Barritt, G J; Rychkov, G Y

    2016-04-01

    Oxidative stress is a hallmark of many liver diseases including viral and drug-induced hepatitis, ischemia-reperfusion injury, and non-alcoholic steatohepatitis. One of the consequences of oxidative stress in the liver is deregulation of Ca(2+) homeostasis, resulting in a sustained elevation of the free cytosolic Ca(2+) concentration ([Ca(2+)]c) in hepatocytes, which leads to irreversible cellular damage. Recently it has been shown that liver damage induced by paracetamol and subsequent oxidative stress is, in large part, mediated by Ca(2+) entry through Transient Receptor Potential Melastatin 2 (TRPM2) channels. Involvement of TRPM2 channels in hepatocellular damage induced by oxidative stress makes TRPM2 a potential therapeutic target for treatment of a range of oxidative stress-related liver diseases. We report here the identification of curcumin ((1E,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione), a natural plant-derived polyphenol in turmeric spice, as a novel inhibitor of TRPM2 channel. Presence of 5µM curcumin in the incubation medium prevented the H2O2- and paracetamol-induced [Ca(2+)]c rise in rat hepatocytes. Furthermore, in patch clamping experiments incubation of hepatocytes with curcumin inhibited activation of TRPM2 current by intracellular ADPR with IC50 of approximately 50nM. These findings enhance understanding of the actions of curcumin and suggest that the known hepatoprotective properties of curcumin are, at least in part, mediated through inhibition of TRPM2 channels. PMID:26609559

  3. Curcumin inhibits activation of TRPM2 channels in rat hepatocytes

    Directory of Open Access Journals (Sweden)

    E. Kheradpezhouh

    2016-04-01

    Full Text Available Oxidative stress is a hallmark of many liver diseases including viral and drug-induced hepatitis, ischemia-reperfusion injury, and non-alcoholic steatohepatitis. One of the consequences of oxidative stress in the liver is deregulation of Ca2+ homeostasis, resulting in a sustained elevation of the free cytosolic Ca2+ concentration ([Ca2+]c in hepatocytes, which leads to irreversible cellular damage. Recently it has been shown that liver damage induced by paracetamol and subsequent oxidative stress is, in large part, mediated by Ca2+ entry through Transient Receptor Potential Melastatin 2 (TRPM2 channels. Involvement of TRPM2 channels in hepatocellular damage induced by oxidative stress makes TRPM2 a potential therapeutic target for treatment of a range of oxidative stress-related liver diseases. We report here the identification of curcumin ((1E,6E-1,7-bis(4-hydroxy-3-methoxyphenyl-1,6-heptadiene-3,5-dione, a natural plant-derived polyphenol in turmeric spice, as a novel inhibitor of TRPM2 channel. Presence of 5 µM curcumin in the incubation medium prevented the H2O2- and paracetamol-induced [Ca2+]c rise in rat hepatocytes. Furthermore, in patch clamping experiments incubation of hepatocytes with curcumin inhibited activation of TRPM2 current by intracellular ADPR with IC50 of approximately 50 nM. These findings enhance understanding of the actions of curcumin and suggest that the known hepatoprotective properties of curcumin are, at least in part, mediated through inhibition of TRPM2 channels.

  4. Myocardial Structural and Biological Anomalies Induced by High Fat Diet in Psammomys obesus Gerbils.

    Directory of Open Access Journals (Sweden)

    Abdelhamid Sahraoui

    Full Text Available Psammomys obesus gerbils are particularly prone to develop diabetes and obesity after brief period of abundant food intake. A hypercaloric high fat diet has been shown to affect cardiac function. Here, we sought to determine whether a short period of high fat feeding might alter myocardial structure and expression of calcium handling proteins in this particular strain of gerbils.Twenty Psammomys obesus gerbils were randomly assigned to receive a normal plant diet (controls or a high fat diet. At baseline and 16-week later, body weight, plasma biochemical parameters (including lipid and carbohydrate levels were evaluated. Myocardial samples were collected for pathobiological evaluation.Sixteen-week high fat dieting resulted in body weight gain and hyperlipidemia, while levels of carbohydrates remained unchanged. At myocardial level, high fat diet induced structural disorganization, including cardiomyocyte hypertrophy, lipid accumulation, interstitial and perivascular fibrosis and increased number of infiltrating neutrophils. Myocardial expressions of pro-apoptotic Bax-to-Bcl-2 ratio, pro-inflammatory cytokines [interleukin (IL-1β and tumor necrosis factor (TNF-α], intercellular (ICAM1 and vascular adhesion molecules (VCAM1 increased, while gene encoding cardiac muscle protein, the alpha myosin heavy polypeptide (MYH6, was downregulated. Myocardial expressions of sarco(endoplasmic calcium-ATPase (SERCA2 and voltage-dependent calcium channel (Cacna1c decreased, while protein kinase A (PKA and calcium-calmodulin-dependent protein kinase (CaMK2D expressions increased. Myocardial expressions of ryanodine receptor, phospholamban and sodium/calcium exchanger (Slc8a1 did not change.We conclude that a relative short period of high fat diet in Psammomys obesus results in severe alterations of cardiac structure, activation of inflammatory and apoptotic processes, and altered expression of calcium-cycling determinants.

  5. Serotonin Improves High Fat Diet Induced Obesity in Mice.

    Directory of Open Access Journals (Sweden)

    Hitoshi Watanabe

    Full Text Available There are two independent serotonin (5-HT systems of organization: one in the central nervous system and the other in the periphery. 5-HT affects feeding behavior and obesity in the central nervous system. On the other hand, peripheral 5-HT also may play an important role in obesity, as it has been reported that 5-HT regulates glucose and lipid metabolism. Here we show that the intraperitoneal injection of 5-HT to mice inhibits weight gain, hyperglycemia and insulin resistance and completely prevented the enlargement of intra-abdominal adipocytes without having any effect on food intake when on a high fat diet, but not on a chow diet. 5-HT increased energy expenditure, O2 consumption and CO2 production. This novel metabolic effect of peripheral 5-HT is critically related to a shift in the profile of muscle fiber type from fast/glycolytic to slow/oxidative in soleus muscle. Additionally, 5-HT dramatically induced an increase in the mRNA expression of peroxisome proliferator-activated receptor coactivator 1α (PGC-1α-b and PGC-1α-c in soleus muscle. The elevation of these gene mRNA expressions by 5-HT injection was inhibited by treatment with 5-HT receptor (5HTR 2A or 7 antagonists. Our results demonstrate that peripheral 5-HT may play an important role in the relief of obesity and other metabolic disorders by accelerating energy consumption in skeletal muscle.

  6. Fluoxetine-induced inhibition of synaptosomal [3H]5-HT release: Possible Ca2+-channel inhibition

    International Nuclear Information System (INIS)

    Fluoxetine, a selective 5-Ht uptake inhibitor, inhibited 15 mM K+-induced [3H]5-HT release from rat spinal cord and cortical synaptosomes at concentrations > 0.5 uM. This effect reflected a property shared by another selective 5-HT uptake inhibitor paroxetine but not by less selective uptake inhibitors such as amitriptyline, desipramine, imipramine or nortriptyline. Inhibition of release by fluoxetine was inversely related to both the concentration of K+ used to depolarize the synaptosomes and the concentration of external Ca2+. Experiments aimed at determining a mechanism of action revealed that fluoxetine did not inhibit voltage-independent release of [3H]5-HT release induced by the Ca2+-ionophore A 23187 or Ca2+-independent release induced by fenfluramine. Moreover the 5-HT autoreceptor antagonist methiothepin did not reverse the inhibitory actions of fluoxetine on K+-induced release. Further studies examined the effects of fluoxetine on voltage-dependent Ca2+ channels and Ca2+ entry

  7. Inhibition of T cell proliferation by selective block of Ca(2+)-activated K(+) channels

    DEFF Research Database (Denmark)

    Jensen, B S; Odum, Niels; Jorgensen, N K;

    1999-01-01

    established. The recent cloning of the Ca(2+)-activated, intermediate-conductance K(+) channel (IK channel) has enabled a detailed investigation of the role of this highly Ca(2+)-sensitive K(+) channel in the calcium signaling and subsequent regulation of T cell proliferation. The role IK channels play in T...... cell activation and proliferation has been investigated by using various blockers of IK channels. The Ca(2+)-activated K(+) current in human T cells is shown by the whole-cell voltage-clamp technique to be highly sensitive to clotrimazole, charybdotoxin, and nitrendipine, but not to ketoconazole...... inhibited after block of IK channels by clotrimazole. Clotrimazole and cyclosporin A act synergistically to inhibit T cell proliferation, which confirms that block of IK channels affects the process downstream from T cell receptor activation. We suggest that IK channels constitute another target for immune...

  8. Inhibition of Escherichia coli chemotaxis by omega-conotoxin, a calcium ion channel blocker.

    OpenAIRE

    Tisa, L S; Olivera, B M; Adler, J

    1993-01-01

    Escherichia coli chemotaxis was inhibited by omega-conotoxin, a calcium ion channel blocker. With Tris-EDTA-permeabilized cells, nanomolar levels of omega-conotoxin inhibited chemotaxis without loss of motility. Cells treated with omega-conotoxin swam with a smooth bias, i.e., tumbling was inhibited.

  9. Mechanism of HERG potassium channel inhibition by tetra-n-octylammonium bromide and benzethonium chloride

    Energy Technology Data Exchange (ETDEWEB)

    Long, Yan; Lin, Zuoxian [Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530 (China); Xia, Menghang; Zheng, Wei [National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892 (United States); Li, Zhiyuan, E-mail: li_zhiyuan@gibh.ac.cn [Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530 (China)

    2013-03-01

    Tetra-n-octylammonium bromide and benzethonium chloride are synthetic quaternary ammonium salts that are widely used in hospitals and industries for the disinfection and surface treatment and as the preservative agent. Recently, the activities of HERG channel inhibition by these compounds have been found to have potential risks to induce the long QT syndrome and cardiac arrhythmia, although the mechanism of action is still elusive. This study was conducted to investigate the mechanism of HERG channel inhibition by these compounds by using whole-cell patch clamp experiments in a CHO cell line stably expressing HERG channels. Tetra-n-octylammonium bromide and benzethonium chloride exhibited concentration-dependent inhibitions of HERG channel currents with IC{sub 50} values of 4 nM and 17 nM, respectively, which were also voltage-dependent and use-dependent. Both compounds shifted the channel activation I–V curves in a hyperpolarized direction for 10–15 mV and accelerated channel activation and inactivation processes by 2-fold. In addition, tetra-n-octylammonium bromide shifted the inactivation I–V curve in a hyperpolarized direction for 24.4 mV and slowed the rate of channel deactivation by 2-fold, whereas benzethonium chloride did not. The results indicate that tetra-n-octylammonium bromide and benzethonium chloride are open-channel blockers that inhibit HERG channels in the voltage-dependent, use-dependent and state-dependent manners. - Highlights: ► Tetra-n-octylammonium and benzethonium are potent HERG channel inhibitors. ► Channel activation and inactivation processes are accelerated by the two compounds. ► Both compounds are the open-channel blockers to HERG channels. ► HERG channel inhibition by both compounds is use-, voltage- and state dependent. ► The in vivo risk of QT prolongation needs to be studied for the two compounds.

  10. Inhibition of parathyroid hormone release by maitotoxin, a calcium channel activator

    International Nuclear Information System (INIS)

    Maitotoxin, a toxin derived from a marine dinoflagellate, is a potent activator of voltage-sensitive calcium channels. To further test the hypothesis that inhibition of PTH secretion by calcium is mediated via a calcium channel we studied the effect of maitotoxin on dispersed bovine parathyroid cells. Maitotoxin inhibited PTH release in a dose-dependent fashion, and inhibition was maximal at 1 ng/ml. Chelation of extracellular calcium by EGTA blocked the inhibition of PTH by maitotoxin. Maitotoxin enhanced the effects of the dihydropyridine calcium channel agonist (+)202-791 and increased the rate of radiocalcium uptake in parathyroid cells. Pertussis toxin, which ADP-ribosylates and inactivates a guanine nucleotide regulatory protein that interacts with calcium channels in the parathyroid cell, did not affect the inhibition of PTH secretion by maitotoxin. Maitotoxin, by its action on calcium channels allows entry of extracellular calcium and inhibits PTH release. Our results suggest that calcium channels are involved in the release of PTH. Inhibition of PTH release by maitotoxin is not sensitive to pertussis toxin, suggesting that maitotoxin may act distal to the site interacting with a guanine nucleotide regulatory protein, or maitotoxin could interact with other ions or second messengers to inhibit PTH release

  11. Inhibition of ATP-sensitive potassium channels by haloperidol

    OpenAIRE

    Yang, Shi-Bing; Proks, Peter; Ashcroft, Frances M.; Rupnik, Marjan

    2004-01-01

    Chronic haloperidol treatment has been associated with an increased incidence of glucose intolerance and type-II diabetes mellitus. We studied the effects of haloperidol on native ATP-sensitive potassium (KATP) channels in mouse pancreatic β cells and on cloned Kir6.2/SUR1 channels expressed in HEK293 cells.The inhibitory effect of haloperidol on the KATP channel was not mediated via the D2 receptor signaling pathway, as both D2 agonists and antagonists blocked the channel.KATP currents were ...

  12. Parametrial fat tissue from high fat diet-treated SKH-1 mice stimulates transformation of mouse epidermal JB6 cells

    OpenAIRE

    Bernard, Jamie J.; Lou, You-Rong; Peng, Qing-Yun; Li, Tao; Vakil, Priyal R.; Ding, Ning; Laskin, Jeffrey D.; Dong, Zigang; Conney, Allan H.; Lu, Yao-Ping

    2014-01-01

    Our previous studies indicated that decreasing visceral adipose tissue by surgical removal of the parametrial fat pads inhibited UVB-induced carcinogenesis in SKH-1 mice fed a high fat diet (HFD), but not a low fat diet (LFD) indicating that the parametrial fat tissue from mice fed a HFD played a role in skin carcinogenesis.

  13. Inhibition of g protein-activated inwardly rectifying k channels by phencyclidine.

    Science.gov (United States)

    Kobayashi, Toru; Nishizawa, Daisuke; Ikeda, Kazutaka

    2011-03-01

    Addictive drugs, such as opioids, ethanol, cocaine, amphetamine, and phencyclidine (PCP), affect many functions of the nervous system and peripheral organs, resulting in severe health problems. G protein-activated inwardly rectifying K(+) (GIRK, Kir3) channels play an important role in regulating neuronal excitability through activation of various Gi/o protein-coupled receptors including opioid and CB(1) cannabinoid receptors. Furthermore, the channels are directly activated by ethanol and inhibited by cocaine at toxic levels, but not affected by methylphenidate, methamphetamine, and 3,4-methylenedioxymethamphetamine (MDMA) at toxic levels. The primary pharmacological action of PCP is blockade of N-methyl-D-aspartate (NMDA) receptor channels that are associated with its psychotomimetic effects. PCP also interacts with several receptors and channels at relatively high concentrations. However, the molecular mechanisms underlying the various effects of PCP remain to be clarified. Here, we investigated the effects of PCP on GIRK channels using the Xenopus oocyte expression system. PCP weakly but significantly inhibited GIRK channels at micromolar concentrations, but not Kir1.1 and Kir2.1 channels. The PCP concentrations effective in inhibiting GIRK channels overlap clinically relevant brain concentrations in severe intoxication. The results suggest that partial inhibition of GIRK channels by PCP may contribute to some of the toxic effects after overdose. PMID:21886598

  14. NOX Activity in Brain Aging: Exacerbation by High Fat Diet

    OpenAIRE

    Bruce-Keller, Annadora J.; White, Christy L.; Gupta, Sunita; Knight, Alecia G.; Pistell, Paul J.; Ingram, Donald K.; Morrison, Christopher D.; Keller, Jeffrey N.

    2010-01-01

    This study describes how age and high fat diet affect the profile of NADPH oxidase (NOX). Specifically, NOX activity and subunit expression were evaluated in the frontal cerebral cortex of 7-, 16-, and 24-month old mice following a 4-month exposure to either Western diet (WD, 41% calories from fat) or very high fat lard diet (VHFD, 60% calories from fat). Data reveal a significant effect of age in on NOX activity, and show that NOX activity was only increased by VHFD, and only in 24-month old...

  15. Oxidative Stress Inhibits Vascular KATP Channels by S-Glutathionylation*

    OpenAIRE

    Yang, Yang; Shi, Weiwei; Cui, Ningren; Wu, Zhongying; Jiang, Chun

    2010-01-01

    The KATP channel is an important player in vascular tone regulation. Its opening and closure lead to vasodilation and vasoconstriction, respectively. Such functions may be disrupted in oxidative stress seen in a variety of cardiovascular diseases, while the underlying mechanism remains unclear. Here, we demonstrated that S-glutathionylation was a modulation mechanism underlying oxidant-mediated vascular KATP channel regulation. An exposure of isolated mesenteric rings to hydrogen peroxide (H2...

  16. Sigma-1 receptor agonists directly inhibit Nav1.2/1.4 channels.

    Directory of Open Access Journals (Sweden)

    Xiao-Fei Gao

    Full Text Available (+-SKF 10047 (N-allyl-normetazocine is a prototypic and specific sigma-1 receptor agonist that has been used extensively to study the function of sigma-1 receptors. (+-SKF 10047 inhibits K(+, Na(+ and Ca2+ channels via sigma-1 receptor activation. We found that (+-SKF 10047 inhibited Na(V1.2 and Na(V1.4 channels independently of sigma-1 receptor activation. (+-SKF 10047 equally inhibited Na(V1.2/1.4 channel currents in HEK293T cells with abundant sigma-1 receptor expression and in COS-7 cells, which barely express sigma-1 receptors. The sigma-1 receptor antagonists BD 1063,BD 1047 and NE-100 did not block the inhibitory effects of (+-SKF-10047. Blocking of the PKA, PKC and G-protein pathways did not affect (+-SKF 10047 inhibition of Na(V1.2 channel currents. The sigma-1 receptor agonists Dextromethorphan (DM and 1,3-di-o-tolyl-guanidine (DTG also inhibited Na(V1.2 currents through a sigma-1 receptor-independent pathway. The (+-SKF 10047 inhibition of Na(V1.2 currents was use- and frequency-dependent. Point mutations demonstrated the importance of Phe(1764 and Tyr(1771 in the IV-segment 6 domain of the Na(V1.2 channel and Phe(1579 in the Na(V1.4 channel for (+-SKF 10047 inhibition. In conclusion, our results suggest that sigma-1 receptor agonists directly inhibit Na(V1.2/1.4 channels and that these interactions should be given special attention for future sigma-1 receptor function studies.

  17. Inhibition of the Cardiac Na+ Channel Nav1.5 by Carbon Monoxide*

    OpenAIRE

    Elies, J; Dallas, M.; Boyle, JP; Scragg, JL; Duke, A; Steele, DS; Peers, C

    2014-01-01

    Sublethal carbon monoxide (CO) exposure is frequently associated with myocardial arrhythmias, and our recent studies have demonstrated that these may be attributable to modulation of cardiac Na(+) channels, causing an increase in the late current and an inhibition of the peak current. Using a recombinant expression system, we demonstrate that CO inhibits peak human Nav1.5 current amplitude without activation of the late Na(+) current observed in native tissue. Inhibition was associated with a...

  18. Cpt-cAMP activates human epithelial sodium channels via relieving self-inhibition

    OpenAIRE

    Molina, Raul; Han, Dong-Yun; Su, Xue-Feng; Zhao, Run-Zhen; Zhao, Meimi; Sharp, Gretta M.; Chang, Yongchang; Ji, Hong-Long

    2011-01-01

    External Na+ self-inhibition is an intrinsic feature of epithelial sodium channels (ENaC). Cpt-cAMP regulates heterologous guinea pig but not rat αβγ ENaC in a ligand-gated manner. We hypothesized that cpt-cAMP may eliminate the self-inhibition of human ENaC thereby open channels. Regulation of self-inhibition by this compound in oocytes was analyzed using the two-electrode voltage clamp and Ussing chamber setups. External cpt-cAMP stimulated human but not rat and murine αβγ ENaC in a dose- a...

  19. Effects of berberine on the growth and immune performance in response to ammonia stress and high-fat dietary in blunt snout bream Megalobrama amblycephala.

    Science.gov (United States)

    Chen, Qing-Qing; Liu, Wen-Bin; Zhou, Man; Dai, Yong-Jun; Xu, Chao; Tian, Hong-Yan; Xu, Wei-Na

    2016-08-01

    This study aimed to figure out the effects of berberine on growth performance, immunity, oxidative stress and hepatocyte apoptosis of blunt snout bream (Megalobrama amblycephala) fed with high-fat diet. 320 fish (80.00 ± 0.90 g) were divided randomly into four trial groups (each with four replicates) and fed with 4 diets (normal diet, normal diet with 50 mg/kg berberine, high-fat diet, high-fat diet with 50 mg/kg berberine), respectively. At the end of the feeding trial, ammonia stress test was carried out for 5 days. The result showed the growth performance, immune parameters including plasm acid phosphatase (ACP) activities, lysozyme (LYZ) activities and alternative complement C3 and C4 contents were suppressed in fish fed with high-fat diets but improved in berberine diets compared with control (normal diet). Hepatopancreas oxidative status, the malondialdehyde (MDA), protein carbonyl (PC) and lipid peroxide (LPO) were increased significantly (P < 0.05) when fish were fed with high-fat diets. Berberine could slow the progression of the oxidative stress induced by high-fat through increasing superoxide dismutase (SOD) activities and total sulfydryl (T-SH) levels of fish. And the hepatocyte apoptosis in the high-fat group could also be alleviated by berberine. After the ammonia stress test, the accumulative mortality was extremely (P < 0.05) low in fish fed high-fat diet with berberine compared to other groups. It was concluded berberine as a functional feed additive significantly inhibited the progression of oxidative stress, reduced the apoptosis and enhanced the immunity of fish fed with high-fat diet. PMID:27235371

  20. Breathing Stimulant Compounds Inhibit TASK-3 Potassium Channel Function Likely by Binding at a Common Site in the Channel Pore.

    Science.gov (United States)

    Chokshi, Rikki H; Larsen, Aaron T; Bhayana, Brijesh; Cotten, Joseph F

    2015-11-01

    Compounds PKTHPP (1-{1-[6-(biphenyl-4-ylcarbonyl)-5,6,7,8-tetrahydropyrido[4,3-d]-pyrimidin-4-yl]piperidin-4-yl}propan-1-one), A1899 (2''-[(4-methoxybenzoylamino)methyl]biphenyl-2-carboxylic acid 2,4-difluorobenzylamide), and doxapram inhibit TASK-1 (KCNK3) and TASK-3 (KCNK9) tandem pore (K2P) potassium channel function and stimulate breathing. To better understand the molecular mechanism(s) of action of these drugs, we undertook studies to identify amino acid residues in the TASK-3 protein that mediate this inhibition. Guided by homology modeling and molecular docking, we hypothesized that PKTHPP and A1899 bind in the TASK-3 intracellular pore. To test our hypothesis, we mutated each residue in or near the predicted PKTHPP and A1899 binding site (residues 118-128 and 228-248), individually, to a negatively charged aspartate. We quantified each mutation's effect on TASK-3 potassium channel concentration response to PKTHPP. Studies were conducted on TASK-3 transiently expressed in Fischer rat thyroid epithelial monolayers; channel function was measured in an Ussing chamber. TASK-3 pore mutations at residues 122 (L122D, E, or K) and 236 (G236D) caused the IC50 of PKTHPP to increase more than 1000-fold. TASK-3 mutants L122D, G236D, L239D, and V242D were resistant to block by PKTHPP, A1899, and doxapram. Our data are consistent with a model in which breathing stimulant compounds PKTHPP, A1899, and doxapram inhibit TASK-3 function by binding at a common site within the channel intracellular pore region, although binding outside the channel pore cannot yet be excluded. PMID:26268529

  1. Irreversible inhibition of epithelial sodium channels by ultraviolet irradiation.

    OpenAIRE

    Cuthbert, A W; Fanestil, D. D.; Herrera, F. C.; Pryn, S. J.

    1982-01-01

    1 The effects of u.v. irradiation at 254 nm and 350 nm on sodium transport across frog skin epithelium have been investigated. 2 Irradiation at 254 nm but not at 350 nm produces a dose-dependent, functionally selective blockade of sodium transport. The effect is apparently due to the irreversible closure of apical sodium channels. 3 The amiloride-sensitive conductance was directly related to sodium transport as measured by short circuit current (SCC) both in normal and irradiated tissues, alt...

  2. A membrane-access mechanism of ion channel inhibition by voltage sensor toxins from spider venom

    Science.gov (United States)

    Lee, Seok-Yong; MacKinnon, Roderick

    2004-07-01

    Venomous animals produce small protein toxins that inhibit ion channels with high affinity. In several well-studied cases the inhibitory proteins are water-soluble and bind at a channel's aqueous-exposed extracellular surface. Here we show that a voltage-sensor toxin (VSTX1) from the Chilean Rose Tarantula (Grammostola spatulata) reaches its target by partitioning into the lipid membrane. Lipid membrane partitioning serves two purposes: to localize the toxin in the membrane where the voltage sensor resides and to exploit the free energy of partitioning to achieve apparent high-affinity inhibition. VSTX1, small hydrophobic poisons and anaesthetic molecules reveal a common theme of voltage sensor inhibition through lipid membrane access. The apparent requirement for such access is consistent with the recent proposal that the sensor in voltage-dependent K+ channels is located at the membrane-protein interface.

  3. Nitric oxide suppresses stomatal opening by inhibiting inward-rectifying Kin channels in Arabidopsis guard cells

    Institute of Scientific and Technical Information of China (English)

    XUE ShaoWu; YANG Pin; HE YiKun

    2008-01-01

    We explore nitric oxide (NO) effect on K+in channels in Arabidopsis guard cells. We observed NO inhib-ited K+in currents when Ca2+ chelator EGTA (Ethylene glycol-bis(2-aminoethylether)-N,N,N',N'tetraacetic acid) was not added in the pipette solution; K+in currents were not sensitive to NO when cytosolic Ca2+ was chelated by EGTA. NO inhibited the Arabidopsis stomatal opening, but when EGTA was added in the bath solution, inhibition effect of NO on stomatal opening vanished. Thus, it implies that NO ele-vates cytosolic Ca2+ by activating plasma membrane Ca2+ channels firstly, then inactivates K+in chan-nels, resulting in stomatal opening suppressed subsequently.

  4. Aluminium and hydrogen ions inhibit a mechanosensory calcium-selective cation channel

    Science.gov (United States)

    Ding, J. P.; Pickard, B. G.

    1993-01-01

    The tension-dependent activity of mechanosensory calcium-selective cation channels in excised plasmalemmal patches from onion bulb scale epidermis is modulated by pH in the physiologically meaningful range between 4.5 and 7.2. It is rapidly lowered by lowering pH and rapidly raised by raising pH. Channel activity is effectively inhibited by low levels of aluminium ions and activity can be partially restored by washing for a few minutes. We suggest that under normal conditions the sensitivity of the mechanosensory channels to pH of the wall free space plays important roles in regulation of plant activities such as growth. We further suggest that, when levels of acid and aluminium ions in the soil solution are high, they might inhibit similar sensory channels in cells of the root tip, thus contributing critically to the acid soil syndrome.

  5. Proton Dependent Inhibition of the Cardiac Sodium Channel Nav1.5 by Ranolazine

    OpenAIRE

    PeterCRuben; SridharanRajamani

    2013-01-01

    Ranolazine is clinically approved for treatment of angina pectoris and is a potential candidate for antiarrhythmic, antiepileptic and analgesic applications. These therapeutic effects of ranolazine hinge on its ability to inhibit persistent or late Na+ currents in a variety of voltage-gated sodium channels. Extracellular acidosis, typical of ischemic events, may alter the efficiency of drug/channel interactions. In this study, we examined pH modulation of ranolazine’s interaction with the ca...

  6. Proton-dependent inhibition of the cardiac sodium channel Nav1.5 by ranolazine

    OpenAIRE

    Sokolov, S.; Peters, C. H.; Rajamani, S; Ruben, P C

    2013-01-01

    Ranolazine is clinically approved for treatment of angina pectoris and is a potential candidate for antiarrhythmic, antiepileptic, and analgesic applications. These therapeutic effects of ranolazine hinge on its ability to inhibit persistent or late Na+ currents in a variety of voltage-gated sodium channels. Extracellular acidosis, typical of ischemic events, may alter the efficiency of drug/channel interactions. In this study, we examined pH modulation of ranolazine's interaction with the ca...

  7. Pinostrobin from Cajanus cajan (L.) Millsp. inhibits sodium channel-activated depolarization of mouse brain synaptoneurosomes.

    Science.gov (United States)

    Nicholson, Russell A; David, Laurence S; Pan, Rui Le; Liu, Xin Min

    2010-10-01

    This investigation focuses on the in vitro neuroactive properties of pinostrobin, a substituted flavanone from Cajanus cajan (L.) Millsp. of the Fabaceae family. We demonstrate that pinostrobin inhibits voltage-gated sodium channels of mammalian brain (IC(50)=23 µM) based on the ability of this substance to suppress the depolarizing effects of the sodium channel-selective activator veratridine in a synaptoneurosomal preparation from mouse brain. The resting membrane potential of synaptoneurosomes was unaffected by pinostrobin. The pharmacological profile of pinostrobin resembles that of depressant drugs that block sodium channels. PMID:20472040

  8. Open State Destabilization by Atp Occupancy Is Mechanism Speeding Burst Exit Underlying KATP Channel Inhibition by Atp

    OpenAIRE

    Li, Lehong; Geng, Xuehui; Drain, Peter

    2002-01-01

    The ATP-sensitive potassium (KATP) channel is named after its characteristic inhibition by intracellular ATP. The inhibition is a centerpiece of how the KATP channel sets electrical signaling to the energy state of the cell. In the β cell of the endocrine pancreas, for example, ATP inhibition results from high blood glucose levels and turns on electrical activity leading to insulin release. The underlying gating mechanism (ATP inhibition gating) includes ATP stabilization of closed states, bu...

  9. Indomethacin inhibits tetrodotoxin-resistant Na(+) channels at acidic pH in rat nociceptive neurons.

    Science.gov (United States)

    Nakamura, Michiko; Jang, Il-Sung

    2016-06-01

    Non-steroidal anti-inflammatory drugs (NSAIDs) are well-known inhibitors of cyclooxygenases (COXs) and are widely used for the treatment of inflammatory pain; however several NSAIDs display COX-independent analgesic action including the inhibition of voltage-gated Na(+) channels expressed in primary afferent neurons. In the present study, we examined whether NSAIDs modulate tetrodotoxin-resistant (TTX-R) Na(+) channels and if this modulation depends on the extracellular pH. The TTX-R Na(+) currents were recorded from small-sized trigeminal ganglion neurons by using a whole-cell patch clamp technique. Among eight NSAIDs tested in this study, several drugs, including aspirin and ibuprofen, did not affect TTX-R Na(+) channels either at pH 7.4 or at pH 6.0. However, we found that indomethacin, and, to a lesser extent, ibuprofen and naproxen potently inhibited the peak amplitude of TTX-R Na(+) currents at pH 6.0. The indomethacin-induced inhibition of TTX-R Na(+) channels was more potent at depolarized membrane potentials. Indomethacin significantly shifted both the voltage-activation and voltage-inactivation relationships to depolarizing potentials at pH 6.0. Indomethacin accelerated the development of inactivation and retarded the recovery from inactivation of TTX-R Na(+) channels at pH 6.0. Given that indomethacin and several other NSAIDs could further suppress local nociceptive signals by inhibiting TTX-R Na(+) channels at an acidic pH in addition to the classical COX inhibition, these drugs could be particularly useful for the treatment of inflammatory pain. PMID:26898291

  10. Englerin A Agonizes the TRPC4/C5 Cation Channels to Inhibit Tumor Cell Line Proliferation.

    Directory of Open Access Journals (Sweden)

    Cheryl Carson

    Full Text Available Englerin A is a structurally unique natural product reported to selectively inhibit growth of renal cell carcinoma cell lines. A large scale phenotypic cell profiling experiment (CLiP of englerin A on ¬over 500 well characterized cancer cell lines showed that englerin A inhibits growth of a subset of tumor cell lines from many lineages, not just renal cell carcinomas. Expression of the TRPC4 cation channel was the cell line feature that best correlated with sensitivity to englerin A, suggesting the hypothesis that TRPC4 is the efficacy target for englerin A. Genetic experiments demonstrate that TRPC4 expression is both necessary and sufficient for englerin A induced growth inhibition. Englerin A induces calcium influx and membrane depolarization in cells expressing high levels of TRPC4 or its close ortholog TRPC5. Electrophysiology experiments confirmed that englerin A is a TRPC4 agonist. Both the englerin A induced current and the englerin A induced growth inhibition can be blocked by the TRPC4/C5 inhibitor ML204. These experiments confirm that activation of TRPC4/C5 channels inhibits tumor cell line proliferation and confirms the TRPC4 target hypothesis generated by the cell line profiling. In selectivity assays englerin A weakly inhibits TRPA1, TRPV3/V4, and TRPM8 which suggests that englerin A may bind a common feature of TRP ion channels. In vivo experiments show that englerin A is lethal in rodents near doses needed to activate the TRPC4 channel. This toxicity suggests that englerin A itself is probably unsuitable for further drug development. However, since englerin A can be synthesized in the laboratory, it may be a useful chemical starting point to identify novel modulators of other TRP family channels.

  11. Tinospora crispa Ameliorates Insulin Resistance Induced by High Fat Diet in Wistar Rats

    OpenAIRE

    Mohd Nazri Abu; Suhana Samat; Norathirah Kamarapani; Fuzina Nor Hussein; Wan Iryani Wan Ismail; Hamzah Fansuri Hassan

    2015-01-01

    The antidiabetic properties of Tinospora crispa, a local herb that has been used in traditional Malay medicine and rich in antioxidant, were explored based on obesity-linked insulin resistance condition. Male Wistar rats were randomly divided into four groups, namely, the normal control (NC) which received standard rodent diet, the high fat diet (HFD) which received high fat diet only, the high fat diet treated with T. crispa (HFDTC), and the high fat diet treated with orlistat (HFDO). After...

  12. Monoclonal Antibodies to the Apical Chloride Channel in Necturus Gallbladder Inhibit the Chloride Conductance

    Science.gov (United States)

    Finn, Arthur L.; Tsai, Lih-Min; Falk, Ronald J.

    1989-10-01

    Monoclonal antibodies raised by injecting Necturus gallbladder cells into mice were tested for their ability to inhibit the apical chloride conductance induced by elevation of cellular cAMP. Five of these monoclonal antibodies bound to the apical cells, as shown by indirect immunofluorescence microscopy, and inhibited the chloride conductance; one antibody that bound only to subepithelial smooth muscle, by indirect immunofluorescence microscopy, showed no inhibition of chloride transport. The channel or a closely related molecule is present in the membrane whether or not the pathway is open, since, in addition to inhibiting the conductance of the open channel, the antibody also bound to the membrane in the resting state and prevented subsequent opening of the channel. The antibody was shown to recognize, by ELISA, epitopes from the Necturus gallbladder and small intestine. Finally, by Western blot analysis of Necturus gallbladder homogenates, the antibody was shown to recognize two protein bands of Mr 219,000 and Mr 69,000. This antibody should permit isolation and characterization of this important ion channel.

  13. State-Dependent Inhibition of Sodium Channels by Local Anesthetics: A 40-Year Evolution.

    Science.gov (United States)

    Wang, G-K; Strichartz, G R

    2012-04-01

    Knowledge about the mechanism of impulse blockade by local anesthetics has evolved over the past four decades, from the realization that Na(+) channels were inhibited to affect the impulse blockade to an identification of the amino acid residues within the Na(+) channel that bind the local anesthetic molecule. Within this period appreciation has grown of the state-dependent nature of channel inhibition, with rapid binding and unbinding at relatively high affinity to the open state, and weaker binding to the closed resting state. Slow binding of high affinity for the inactivated state accounts for the salutary therapeutic as well as the toxic actions of diverse class I anti-arrhythmic agents, but may have little importance for impulse blockade, which requires concentrations high enough to block the resting state. At the molecular level, residues on the S6 transmembrane segments in three of the homologous domains of the channel appear to contribute to the binding of local anesthetics, with some contribution also from parts of the selectivity filter. Binding to the inactivated state, and perhaps the open state, involves some residues that are not identical to those that bind these drugs in the resting state, suggesting spatial flexibility in the "binding site". Questions remaining include the mechanism that links local anesthetic binding with the inhibition of gating charge movements, and the molecular nature of the theoretical "hydrophobic pathway" that may be critical for determining the recovery rates from blockade of closed channels, and thus account for both therapeutic and cardiotoxic actions. PMID:23710324

  14. Shikonin Inhibits Intestinal Calcium-Activated Chloride Channels and Prevents Rotaviral Diarrhea.

    Science.gov (United States)

    Jiang, Yu; Yu, Bo; Yang, Hong; Ma, Tonghui

    2016-01-01

    Secretory diarrhea remains a global health burden and causes major mortality in children. There have been some focuses on antidiarrheal therapies that may reduce fluid losses and intestinal motility in diarrheal diseases. In the present study, we identified shikonin as an inhibitor of TMEM16A chloride channel activity using cell-based fluorescent-quenching assay. The IC50 value of shikonin was 6.5 μM. Short-circuit current measurements demonstrated that shikonin inhibited Eact-induced Cl(-) current in a dose-dependent manner, with IC50 value of 1.5 μM. Short-circuit current measurement showed that shikonin exhibited inhibitory effect against CCh-induced Cl(-) currents in mouse colonic epithelia but did not affect cytoplasmic Ca(2+) concentration as well as the other major enterocyte chloride channel conductance regulator. Characterization study found that shikonin inhibited basolateral K(+) channel activity without affecting Na(+)/K(+)-ATPase activities. In vivo studies revealed that shikonin significantly delayed intestinal motility in mice and reduced stool water content in a neonatal mice model of rotaviral diarrhea without affecting the viral infection process in vivo. Taken together, the results suggested that shikonin inhibited enterocyte calcium-activated chloride channels, the inhibitory effect was partially through inhbition of basolateral K(+) channel activity, and shikonin could be a lead compound in the treatment of rotaviral secretory diarrhea. PMID:27601995

  15. Selective inhibition of a slow-inactivating voltage-dependent K+ channel in rat PC12 cells by hypoxia.

    Science.gov (United States)

    Conforti, L; Millhorn, D E

    1997-07-15

    1. Electrophysiological (single-channel patch clamp) and molecular biological experiments (reverse transcriptase-polymerase chain reaction) were performed to attempt to identify the O2-sensitive K+ channel in rat phaeochromocytoma (PC12) cells. 2. Four types of K+ channels were recorded in PC12 cells: a small-conductance K+ channel (14 pS), a calcium-activated K+ channel (KCa; 102 pS) and two K+ channels with similar conductance (20 pS). These last two channels differed in their time-dependent inactivation: one was a slow-inactivating channel, while the other belonged to the family of fast transient K+ channels. 3. The slow-inactivating 20 pS K+ channel was inhibited by hypoxia. Exposure to hypoxia produced a 50% reduction in channel activity (number of active channels in the patch x open probability). Hypoxia had no effect on the 20 pS transient K+ channels, whereas reduced O2 stimulated the KCa channels. 4. The genes encoding the alpha-subunits of slow-inactivating K+ channels for two members of the Shaker subfamily of K+ channels (Kv1.2 and Kv1.3) together with the Kv2.1, Kv3.1 and Kv3.2 channel genes were identified in PC12 cells. 5. The expression of the Shaker Kv1.2, but none of the other K+ channel genes, increased in cells exposed to prolonged hypoxia (18 h). The same cells were more responsive to a subsequent exposure to hypoxia (35% inhibition of K+ current measured in whole-cell voltage clamp) compared with the cells maintained in normoxia (19% inhibition). 6. These results indicate that the O2-sensitive K+ channel in PC12 cells is a 20 pS slow-inactivating K+ channel that is upregulated by hypoxia. This channel appears to belong to the Shaker subfamily of voltage-gated K+ channels. PMID:9263911

  16. Effects of high fat diet on incidence of spontaneous tumors in Wistar rats

    DEFF Research Database (Denmark)

    KRISTIANSEN, E.; Madsen, Charlotte Bernhard; Meyer, Otto A.; ROSWALL, K.; THORUP, I.

    1993-01-01

    a high-fat diet influenced the tumor incidence in certain organs of rats. However, the overall differences in tumor incidence between rats fed the low- and the high-fat diet are considered marginal Therefore we were not able to confirm or deny the hypothesis that a high-fat diet promotes the...

  17. Suppressing effect of C a2 + blips on puff amplitudes by inhibiting channels to prevent recovery

    Science.gov (United States)

    Chen, Yuan; Qi, Hong; Li, Xiang; Cai, Meichun; Chen, Xingqiang; Liu, Wen; Shuai, Jianwei

    2016-08-01

    As local signals, calcium puffs arise from the concerted opening of a few nearby inositol 1,4,5-trisphospate receptor channels to release C a2 + ions from the endoplasmic reticulum. Although C a2 + puffs have been well studied, little is known about the modulation of cytosolic basal C a2 + concentration ([Ca2 +] Basal) on puff dynamics. In this paper we consider a puff model to study how the statistical properties of puffs are modulated by [Ca2 +] Basal. The puff frequency and lifetime trivially increase with the increasing [Ca2 +] Basal, but an unexpected result is that the puff amplitude and the maximum open-channel number of the puff show decreasing relationship with the increasing [Ca2 +] Basal. The underlying dynamics is related not only to the increasing puff frequency which gives a shorter recovery time, but also to the increasing frequency of blips with only one channel open. We indicate that C a2 + blips cause the channels to be inhibited and prevent their recovery during interpuff intervals, resulting in the suppressing effect on puff amplitudes. With increasing [Ca2 +] Basal, more blips occur to cause more channels to be inhibited, leaving fewer channels available for puff events. This study shows that the blips may play relevant functions in global C a2 + waves through modulating puff dynamics.

  18. Inhibition of G protein-activated inwardly rectifying K+ channels by different classes of antidepressants.

    Directory of Open Access Journals (Sweden)

    Toru Kobayashi

    Full Text Available Various antidepressants are commonly used for the treatment of depression and several other neuropsychiatric disorders. In addition to their primary effects on serotonergic or noradrenergic neurotransmitter systems, antidepressants have been shown to interact with several receptors and ion channels. However, the molecular mechanisms that underlie the effects of antidepressants have not yet been sufficiently clarified. G protein-activated inwardly rectifying K(+ (GIRK, Kir3 channels play an important role in regulating neuronal excitability and heart rate, and GIRK channel modulation has been suggested to have therapeutic potential for several neuropsychiatric disorders and cardiac arrhythmias. In the present study, we investigated the effects of various classes of antidepressants on GIRK channels using the Xenopus oocyte expression assay. In oocytes injected with mRNA for GIRK1/GIRK2 or GIRK1/GIRK4 subunits, extracellular application of sertraline, duloxetine, and amoxapine effectively reduced GIRK currents, whereas nefazodone, venlafaxine, mianserin, and mirtazapine weakly inhibited GIRK currents even at toxic levels. The inhibitory effects were concentration-dependent, with various degrees of potency and effectiveness. Furthermore, the effects of sertraline were voltage-independent and time-independent during each voltage pulse, whereas the effects of duloxetine were voltage-dependent with weaker inhibition with negative membrane potentials and time-dependent with a gradual decrease in each voltage pulse. However, Kir2.1 channels were insensitive to all of the drugs. Moreover, the GIRK currents induced by ethanol were inhibited by sertraline but not by intracellularly applied sertraline. The present results suggest that GIRK channel inhibition may reveal a novel characteristic of the commonly used antidepressants, particularly sertraline, and contributes to some of the therapeutic effects and adverse effects.

  19. High-fat diet alters gut microbiota physiology in mice

    OpenAIRE

    Daniel, Hannelore; Gholami, Amin Moghaddas; Berry, David; Desmarchelier, Charles; Hahne, Hannes; Loh, Gunnar; Mondot, Stanislas; Lepage, Patricia; Rothballer, Michael; Walker, Alesia; Böhm, Christoph; Wenning, Mareike; Wagner, Michael; Blaut, Michael; Schmitt-Kopplin, Philippe

    2013-01-01

    The intestinal microbiota is known to regulate host energy homeostasis and can be influenced by high-calorie diets. However, changes affecting the ecosystem at the functional level are still not well characterized. We measured shifts in cecal bacterial communities in mice fed a carbohydrate or high-fat (HF) diet for 12 weeks at the level of the following: (i) diversity and taxa distribution by high-throughput 16S ribosomal RNA gene sequencing; (ii) bulk and single-cell chemical composition by...

  20. Cream and sugar: human preferences for high-fat foods.

    Science.gov (United States)

    Drewnowski, A; Greenwood, M R

    1983-04-01

    Sixteen normal-weight subjects rated the perceived intensity of sweetness, fatness, and creaminess of 20 different mixtures of milk, cream, and sugar, and assigned an overall pleasantness (hedonic) rating to each sample. Intensity estimates increased as power functions of ingredient concentration and no significant mixture suppression effect was observed. In contrast, hedonic responses strongly depended on the relative proportions of sucrose and fat in the samples tasted. Hedonic preference ratings first rose and then declined with increasing sucrose concentration, but continued to rise with increasing dairy fat content. The addition of sucrose greatly enhanced hedonic ratings for high-fat stimuli. Changes in hedonic responsiveness were monitored using a mathematical modelling technique known as the Response Surface Method, which allows computerized simulation of the hedonic response surface as a function of perceived ingredient levels. Overnight fasting did not affect the perception or hedonics for sweet or "fatty" tastes. The observed preference for sweetened high-fat foods may have implications for the development of dietary-induced obesity in man. PMID:6878464

  1. Specific inhibition of long-lasting, L-type calcium channels by synthetic parathyroid hormone

    International Nuclear Information System (INIS)

    The effect of an active synthetic N-terminal fragment of bovine parathyroid hormone (bPTH), bPTH-(1-34), on Ca2+ channels was studied in mouse neuroblastoma cells (N1E-115). With the whole-cell variation of the patch-clamp technique, T (transient) and L (long-lasting) types of Ca2+ currents were identified. Pharmacological characterization showed that the L current was amplified by the Ca2+ channel stimulator BAY K-8644, but the T current was unaffected. The administration of bPTH-(1-34) produced dose-related inhibition of the L current, which could be reversed by BAY K-8644. The peptide had no effect on the T current. In addition, use of the fluorescent indicator fura-2 showed that bPTH-(1-34) inhibited the KCl-stimulated increase in intracellular free Ca2+ in neuroblastoma cells with L channels but not in cells with T channels. An inactivated (oxidized) preparation of bPTH-(1-34) failed to affect the L current. High-affinity binding of labeled PTH analog to these neuroblastoma cells was also demonstrated. In addition, bPTH-(1-34) inhibited the L current in cultured vascular smooth muscle cells from rat tail artery. These data indicate that, in some tissues PTH can act as an endogenous blocker of Ca2+ entry

  2. Calpeptin, not calpain, directly inhibits an ion channel of the inner mitochondrial membrane.

    Science.gov (United States)

    Derksen, Maria; Vorwerk, Christian; Siemen, Detlef

    2016-05-01

    The permeability transition pore (PTP) of inner mitochondrial membranes is a large conductance pathway for ions up to 1500 Da which opening is responsible for ion equilibration and loss of membrane potential in apoptosis and thus in several neurodegenerative diseases. The PTP can be regulated by the Ca(2+)-activated mitochondrial K channel (BK). Calpains are Ca(2+)-activated cystein proteases; calpeptin is an inhibitor of calpains. We wondered whether calpain or calpeptin can modulate activity of PTP or BK. Patch clamp experiments were performed on mitoplasts of rat liver (PTP) and of an astrocytoma cell line (BK). Channel-independent open probability (P o) was determined (PTP) and, taking into account the number of open levels, NPo by single channel analysis (BK). We find that PTP in the presence of Ca(2+) (200 μM) is uninfluenced by calpain (13 nM) and shows insignificant decrease by the calpain inhibitor calpeptin (1 μM). The NPo of the BK is insensitive to calpain (54 nM), too. However, it is significantly and reversibly inhibited by the calpain inhibitor calpeptin (IC50 = 42 μM). The results agree with calpeptin-induced activation of the PTP via inhibition of the BK. Screening experiments with respirometry show calpeptin effects, fitting to inhibition of the BK by calpeptin, and strong inhibition of state 3 respiration. PMID:26108743

  3. Islet Cell Response to High Fat Programming in Neonate, Weanling and Adolescent Wistar Rats

    Directory of Open Access Journals (Sweden)

    Marlon E. Cerf

    2014-05-01

    Full Text Available Context High fat programming, by exposure to a high saturated fat diet during fetal and/or lactational life induces metabolic derangements and alters islet cell architecture in neonate and weanling rats. Objective The present study assessed metabolic hanges and islet cell dynamics in response to high fat maintenance during specific developmental periods in adolescent rats, with some parameters also studied in neonate and weanling rats. Methods The experimental groups comprised neonates, weanlings and adolescents maintained on a high fat diet during specific periods of fetal, lactational and/or postnatal life. Control neonates, weanlings and adolescents were maintained on a standard laboratory (control or low fat diet. Results Fetal high fat programmed (i.e., maintained on a high fat diet exclusively during fetal life neonates were insulin resistant. Weanlings maintained on a high fat diet throughout fetal and lactational life had increased pancreas weights. Fetal high fat programmed adolescents presented a normal phenotype mimicking the control adolescents. Adolescents maintained on a postnatal high fat diet had increased body weights, hyperglycemia, hyperinsulinemia, hyperleptinemia and insulin resistance displaying beta cell hypertrophy and increased islet cell proliferation. Adolescents maintained on a fetal and postnatal high fat diet had increased body weights, hyperleptinemia, hyperinsulinemia and insulin resistance. Conclusions High fat programming induces various diabetogenic phenotypes which present at different life stages. The postnatal period from birth to adolescence representsan extension for high fat programming of metabolic disease.

  4. Mechanism of inhibition of calcium channels in rat nucleus tractus solitarius by neurotransmitters.

    OpenAIRE

    Rhim, H; Toth, P. T.; Miller, R. J.

    1996-01-01

    1. High-threshold Ca2+ channel currents were measured every 15 s following a 200 ms voltage step from -80 mV to 0 mV in order to study the coupling mechanism between neurotransmitter receptors and Ca2+ channels in neurones acutely isolated from the nucleus tractus solitarius (NTS) of the rat. 2. Application of 30 microM baclofen (GABAB receptor agonist) caused 38.9 +/- 1.2% inhibition of the peak inward Ba2+ current (IBa2+) in most NTS cells tested (n = 85 of 88). Somatostatin, 300 nM, also r...

  5. K+ channel openers restore verapamil-inhibited lung fluid resolution and transepithelial ion transport

    Directory of Open Access Journals (Sweden)

    Su Xue-Feng

    2010-05-01

    Full Text Available Abstract Background Lung epithelial Na+ channels (ENaC are regulated by cell Ca2+ signal, which may contribute to calcium antagonist-induced noncardiogenic lung edema. Although K+ channel modulators regulate ENaC activity in normal lungs, the therapeutical relevance and the underlying mechanisms have not been completely explored. We hypothesized that K+ channel openers may restore calcium channel blocker-inhibited alveolar fluid clearance (AFC by up-regulating both apical and basolateral ion transport. Methods Verapamil-induced depression of heterologously expressed human αβγ ENaC in Xenopus oocytes, apical and basolateral ion transport in monolayers of human lung epithelial cells (H441, and in vivo alveolar fluid clearance were measured, respectively, using the two-electrode voltage clamp, Ussing chamber, and BSA protein assays. Ca2+ signal in H441 cells was analyzed using Fluo 4AM. Results The rate of in vivo AFC was reduced significantly (40.6 ± 6.3% of control, P Ca3.1 (1-EBIO and KATP (minoxidil channel openers significantly recovered AFC. In addition to short-circuit current (Isc in intact H441 monolayers, both apical and basolateral Isc levels were reduced by verapamil in permeabilized monolayers. Moreover, verapamil significantly altered Ca2+ signal evoked by ionomycin in H441 cells. Depletion of cytosolic Ca2+ in αβγ ENaC-expressing oocytes completely abolished verapamil-induced inhibition. Intriguingly, KV (pyrithione-Na, K Ca3.1 (1-EBIO, and KATP (minoxidil channel openers almost completely restored the verapamil-induced decrease in Isc levels by diversely up-regulating apical and basolateral Na+ and K+ transport pathways. Conclusions Our observations demonstrate that K+ channel openers are capable of rescuing reduced vectorial Na+ transport across lung epithelial cells with impaired Ca2+ signal.

  6. Inhibition of KV7 Channels Protects the Rat Heart against Myocardial Ischemia and Reperfusion Injury.

    Science.gov (United States)

    Hedegaard, Elise R; Johnsen, Jacob; Povlsen, Jonas A; Jespersen, Nichlas R; Shanmuganathan, Jeffrey A; Laursen, Mia R; Kristiansen, Steen B; Simonsen, Ulf; Bøtker, Hans Erik

    2016-04-01

    The voltage-gated KV7 (KCNQ) potassium channels are activated by ischemia and involved in hypoxic vasodilatation. We investigated the effect of KV7 channel modulation on cardiac ischemia and reperfusion injury and its interaction with cardioprotection by ischemic preconditioning (IPC). Reverse-transcription polymerase chain reaction revealed expression of KV7.1, KV7.4, and KV7.5 in the left anterior descending rat coronary artery and all KV7 subtypes (KV7.1-KV7.5) in the left and right ventricles of the heart. Isolated hearts were subjected to no-flow global ischemia and reperfusion with and without IPC. Infarct size was quantified by 2,3,5-triphenyltetrazolium chloride staining. Two blockers of KV7 channels, XE991 [10,10-bis(4-pyridinylmethyl)-9(10H)-anthracenone] (10 µM) and linopirdine (10 µM), reduced infarct size and exerted additive infarct reduction to IPC. An opener of KV7 channels, flupirtine (10 µM) abolished infarct size reduction by IPC. Hemodynamics were measured using a catheter inserted in the left ventricle and postischemic left ventricular recovery improved in accordance with reduction of infarct size and deteriorated with increased infarct size. XE991 (10 µM) reduced coronary flow in the reperfusion phase and inhibited vasodilatation in isolated small branches of the left anterior descending coronary artery during both simulated ischemia and reoxygenation. KV7 channels are expressed in rat coronary arteries and myocardium. Inhibition of KV7 channels exerts cardioprotection and opening of KV7 channels abrogates cardioprotection by IPC. Although safety issues should be further addressed, our findings suggest a potential role for KV7 blockers in the treatment of ischemia-reperfusion injury. PMID:26869667

  7. Englerin A Agonizes the TRPC4/C5 Cation Channels to Inhibit Tumor Cell Line Proliferation

    OpenAIRE

    Carson, Cheryl; Raman, Pichai; Tullai, Jennifer; Xu, Lei; Henault, Martin; Thomas, Emily; Yeola, Sarita; Lao, Jianmin; McPate, Mark; Verkuyl, J. Martin; Marsh, George; Sarber, Jason; Amaral, Adam; Bailey, Scott; Lubicka, Danuta

    2015-01-01

    Englerin A is a structurally unique natural product reported to selectively inhibit growth of renal cell carcinoma cell lines. A large scale phenotypic cell profiling experiment (CLiP) of englerin A on ¬over 500 well characterized cancer cell lines showed that englerin A inhibits growth of a subset of tumor cell lines from many lineages, not just renal cell carcinomas. Expression of the TRPC4 cation channel was the cell line feature that best correlated with sensitivity to englerin A, suggest...

  8. Substance P Depolarizes Lamprey Spinal Cord Neurons by Inhibiting Background Potassium Channels

    OpenAIRE

    Thörn Pérez, Carolina; Hill, Russell H.; Grillner, Sten

    2015-01-01

    Substance P is endogenously released in the adult lamprey spinal cord and accelerates the burst frequency of fictive locomotion. This is achieved by multiple effects on interneurons and motoneurons, including an attenuation of calcium currents, potentiation of NMDA currents and reduction of the reciprocal inhibition. While substance P also depolarizes spinal cord neurons, the underlying mechanism has not been resolved. Here we show that effects of substance P on background K+ channels are the...

  9. Inhibition of cation channel function at the nicotinic acethylcholine receptor from Torpedo: Agonist self-inhibition and anesthetic drugs

    International Nuclear Information System (INIS)

    Modulation of the nicotinic acethylcholine receptor from Torpedo by cholinergic agonists, local anesthetics, and n-alkanols was studied using 86Rb+ flux studies in sealed native Torpedo electroplaque membrane vesicles. Reliable concentration-response and kinetic data were obtained using manual ten sec filtration assays in vesicles partially blocked with alpha-bungarotoxin to remove spare receptors and quenched-flow assays to assess initial 86Rb+ flux rates or the rate of drug-induced receptor inactivation. Concentration response relationships for the agonists acetylcholine, carbamylcholine, suberyldicholine, phenyltrimethylammonium, and (-)-nicotine are all bell-shape due to stimulation of cation channel opening at low concentrations and inhibition of channels at higher concentrations. The rate of agonist-induced fast desensitization (kd) increases with [acetylcholine] in parallel with channel activation, suggesting that desensitization proceeds from the open state and/or states in rapid equilibrium with it. At self-inhibitory acetylcholine concentrations, a new rapid inactivation (rate = kf) is observed before fast desensitization. The rate and extent of rapid inactivation is compatible with bimolecular association between acethylcholine and inhibitory site with KB = 40 mM

  10. Inhibition of intestinal motility by the putative BK(Ca) channel opener LDD175.

    Science.gov (United States)

    Dela Peña, Ike Campomayor; Yoon, Seo Young; Kim, Sung Mok; Lee, Geum Seon; Park, Chul-Seung; Kim, Yong Chul; Cheong, Jae Hoon

    2009-03-01

    LDD175 (4-chloro-7-trifluoromethyl-10H-benzo[4,5]furo[3,2-b]indole-1-carboxylic acid) is a benzofuroindole compound characterized previously as a potent opener of the large conductance calcium activated (BK(Ca)) channels. Activators of the BK(Ca) channels are potential therapies for smooth muscle hyperactivity disorders. The present study investigates the influence of LDD175 on the mechanical activity of the ileum smooth muscle. LDD175 inhibited spontaneous contractions of the ileum in a concentration-dependent manner (pEC(50)=5.9 +/- 0.1) (E (max)=96 +/- 1.0% at 100 muM, n=3). It also remarkably inhibited contractions due to acetylcholine (ACh) (pEC(50)=5.3 +/- 0.1)(E (max)=97.7 +/- 2.3%, n=6) and electrical field stimulation (EFS) (pEC(50)=5.5 +/- 0.1) (E (max)=83.3 +/- 6.0%, n=6). In strips precontracted by 20 mM KCl, LDD175 significantly reduced the contractions yielding a pEC(50) of 6.1 +/- 0.1 and E (max) of 96.6 +/- 0.9%, (n=6). In 60 mM KCl, a concentration-dependent inhibition was observed with respective pEC(50) and E (max) values of 4.1 +/- 0.1 and 50.8 +/- 5.0% (n=3). BK(Ca) channel blockers iberiotoxin (IbTX) and tetraethylammonium chloride (TEA, 1 mM) attenuated the relaxative effect of LDD175 but not barium chloride (BaCl(2)), and glibenclamide (K(IR) and K(ATP) channel blockers, respectively). These data demonstrate the antispasmodic activity of LDD175 attributable to the potentiation of the BK(Ca) channels. PMID:19387586

  11. Extracellular potassium inhibits Kv7.1 potassium channels by stabilizing an inactivated state

    DEFF Research Database (Denmark)

    Larsen, Anders Peter; Steffensen, Annette Buur; Grunnet, Morten; Olesen, Søren-Peter

    2011-01-01

    Kv7.1 (KCNQ1) channels are regulators of several physiological processes including vasodilatation, repolarization of cardiomyocytes, and control of secretory processes. A number of Kv7.1 pore mutants are sensitive to extracellular potassium. We hypothesized that extracellular potassium also...... modulates wild-type Kv7.1 channels. The Kv7.1 currents were measured in Xenopus laevis oocytes at different concentrations of extracellular potassium (1-50 mM). As extracellular potassium was elevated, Kv7.1 currents were reduced significantly more than expected from theoretical calculations based on the...... Goldman-Hodgkin-Katz flux equation. Potassium inhibited the steady-state current with an IC(50) of 6.0 ± 0.2 mM. Analysis of tail-currents showed that potassium increased the fraction of channels in the inactivated state. Similarly, the recovery from inactivation was slowed by potassium, suggesting that...

  12. Structure, inhibition and regulation of two-pore channel TPC1 from Arabidopsis thaliana.

    Science.gov (United States)

    Kintzer, Alexander F; Stroud, Robert M

    2016-03-10

    Two-pore channels (TPCs) comprise a subfamily (TPC1-3) of eukaryotic voltage- and ligand-gated cation channels with two non-equivalent tandem pore-forming subunits that dimerize to form quasi-tetramers. Found in vacuolar or endolysosomal membranes, they regulate the conductance of sodium and calcium ions, intravesicular pH, trafficking and excitability. TPCs are activated by a decrease in transmembrane potential and an increase in cytosolic calcium concentrations, are inhibited by low luminal pH and calcium, and are regulated by phosphorylation. Here we report the crystal structure of TPC1 from Arabidopsis thaliana at 2.87 Å resolution as a basis for understanding ion permeation, channel activation, the location of voltage-sensing domains and regulatory ion-binding sites. We determined sites of phosphorylation in the amino-terminal and carboxy-terminal domains that are positioned to allosterically modulate cytoplasmic Ca(2+) activation. One of the two voltage-sensing domains (VSD2) encodes voltage sensitivity and inhibition by luminal Ca(2+) and adopts a conformation distinct from the activated state observed in structures of other voltage-gated ion channels. The structure shows that potent pharmacophore trans-Ned-19 (ref. 17) acts allosterically by clamping the pore domains to VSD2. In animals, Ned-19 prevents infection by Ebola virus and other filoviruses, presumably by altering their fusion with the endolysosome and delivery of their contents into the cytoplasm. PMID:26961658

  13. Inhibition of TRPV1 channels enables long-term potentiation in the entorhinal cortex.

    Science.gov (United States)

    Banke, Tue G

    2016-04-01

    The transient receptor potential vanilloid 1 (TRPV1) channel is a non-selective cation channel that is mainly found in nociceptive neurons of the peripheral nervous system; however, these channels have also been located within the CNS, including the entorhinal cortex. Whole-cell patch-clamp recordings of principal entorhinal cortex (EC) layers II/III neurons revealed that evoked inhibitory postsynaptic currents were depressed by application of the TRPV1 agonist capsaicin (CAP), accompanied by a change in the pair-pulse ratio (PPR). In addition, recordings of miniature inhibitory postsynaptic currents (mIPSCs) revealed that inter-event intervals but not amplitude were decreased in wild-type (WT) after application of CAP. This suggests that TRPV1 channels are functional in the entorhinal cortex and are located on inhibitory neurons with their axonal arborization within layers II/III. In order to study TRPV1 channels and their involvement in long-term potentiation (LTP) induction in a more intact circuit, extracellular field potential recordings were performed in EC layers II/III. It was found that activated TRPV1 channels preclude induction of long-term potentiation. In sharp contrast, clear LTP was observed when antagonizing TRPV1 channels or recording from TRPV1 knock-out mice. Thus, these results suggests that signaling through activating inhibitory presynaptic TRPV1 channels represents a novel mechanism by which a shift in feed-forward inhibition of layers II/III cortical principal neurons prompt changes in synaptic strength and thereby contribute to a change of information storage within the brain. PMID:26729265

  14. Fluoxetine-induced inhibition of synaptosomal ( sup 3 H)5-HT release: Possible Ca sup 2+ -channel inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Stauderman, K.A. (Marion Merrell Dow Research Inst., Cincinnati, OH (United States)); Gandhi, V.C.; Jones, D.J. (Univ. of Texas Health Science Center, San Antonio, TX (United States))

    1992-01-01

    Fluoxetine, a selective 5-Ht uptake inhibitor, inhibited 15 mM K{sup +}-induced ({sup 3}H)5-HT release from rat spinal cord and cortical synaptosomes at concentrations > 0.5 uM. This effect reflected a property shared by another selective 5-HT uptake inhibitor paroxetine but not by less selective uptake inhibitors such as amitriptyline, desipramine, imipramine or nortriptyline. Inhibition of release by fluoxetine was inversely related to both the concentration of K{sup +} used to depolarize the synaptosomes and the concentration of external Ca{sup 2+}. Experiments aimed at determining a mechanism of action revealed that fluoxetine did not inhibit voltage-independent release of ({sup 3}H)5-HT release induced by the Ca{sup 2+}-ionophore A 23187 or Ca{sup 2+}-independent release induced by fenfluramine. Moreover the 5-HT autoreceptor antagonist methiothepin did not reverse the inhibitory actions of fluoxetine on K{sup +}-induced release. Further studies examined the effects of fluoxetine on voltage-dependent Ca{sup 2+} channels and Ca{sup 2+} entry.

  15. Effect of Ginseng (Panax ginseng Berry EtOAc Fraction on Cognitive Impairment in C57BL/6 Mice under High-Fat Diet Inducement

    Directory of Open Access Journals (Sweden)

    Chang Hyeon Park

    2015-01-01

    Full Text Available High-fat diet-induced obesity leads to type 2 diabetes. Recently, there has been growing apprehension about diabetes-associated cognitive impairment (DACM. The effect of ginseng (Panax ginseng berry ethyl acetate fraction (GBEF on mice with high-fat diet-induced cognitive impairment was investigated to confirm its physiological function. C57BL/6 mice were fed a high-fat diet for 5 weeks and then a high-fat diet with GBEF (20 and 50 mg/kg of body weight for 4 weeks. After three in vivo behavioral tests (Y-maze, passive avoidance, and Morris water maze tests, blood samples were collected from the postcaval vein for biochemical analysis, and whole brains were prepared for an ex vivo test. A method based on ultra-performance liquid chromatography (UPLC accurate-mass quadrupole time-of-flight mass spectrometry (Q-TOF/MS was used to determine major ginsenosides. GBEF decreased the fasting blood glucose levels of high-fat diet-induced diabetes mellitus (DM mice and improved hyperglycemia. Cognitive behavior tests were examined after setting up the DM mice. The in vivo experiments showed that mice treated with GBEF exhibited more improved cognitive behavior than DM mice. In addition, GBEF effectively inhibited the acetylcholinesterase (AChE activity and malondialdehyde (MDA levels of DM mice brain tissues. Q-TOF UPLC/MS analyses of GBEF showed that ginsenoside Re was the major ginsenoside.

  16. Effect of Ginseng (Panax ginseng) Berry EtOAc Fraction on Cognitive Impairment in C57BL/6 Mice under High-Fat Diet Inducement.

    Science.gov (United States)

    Park, Chang Hyeon; Park, Seon Kyeong; Seung, Tae Wan; Jin, Dong Eun; Guo, Tianjiao; Heo, Ho Jin

    2015-01-01

    High-fat diet-induced obesity leads to type 2 diabetes. Recently, there has been growing apprehension about diabetes-associated cognitive impairment (DACM). The effect of ginseng (Panax ginseng) berry ethyl acetate fraction (GBEF) on mice with high-fat diet-induced cognitive impairment was investigated to confirm its physiological function. C57BL/6 mice were fed a high-fat diet for 5 weeks and then a high-fat diet with GBEF (20 and 50 mg/kg of body weight) for 4 weeks. After three in vivo behavioral tests (Y-maze, passive avoidance, and Morris water maze tests), blood samples were collected from the postcaval vein for biochemical analysis, and whole brains were prepared for an ex vivo test. A method based on ultra-performance liquid chromatography (UPLC) accurate-mass quadrupole time-of-flight mass spectrometry (Q-TOF/MS) was used to determine major ginsenosides. GBEF decreased the fasting blood glucose levels of high-fat diet-induced diabetes mellitus (DM) mice and improved hyperglycemia. Cognitive behavior tests were examined after setting up the DM mice. The in vivo experiments showed that mice treated with GBEF exhibited more improved cognitive behavior than DM mice. In addition, GBEF effectively inhibited the acetylcholinesterase (AChE) activity and malondialdehyde (MDA) levels of DM mice brain tissues. Q-TOF UPLC/MS analyses of GBEF showed that ginsenoside Re was the major ginsenoside. PMID:26161118

  17. Isoflavone Regulates Lipid Metabolism via Expression of Related Genes in OVX Rats Fed on a High-fat Diet

    Institute of Scientific and Technical Information of China (English)

    XIAO-LIN NA; JUNKO EZAKI; FUMIE SUGIYAMA; HONG-BIN CUI; YOSHIKO ISHIMI

    2008-01-01

    Objective To investigate the effects of isoflavone on body weight, fat mass, and gene expression in relation to lipid metabolism. Methods Thirty-six female SD rats were variectomized or sham-operated and fed on a high-fat diet. Two months later, abdominal incision was made, blood was collected to separate serum, and the liver and adipose tissue were immediately collected and weighed. Some portions of these tissues were frozen in liquid nitrogen and stored at -80℃. Results Ovariectomy (OVX) with a high-fat diet could induce obesity in rats, while treatment with isoflavone significantly inhibited the increase in body weight and fat mass in abdomen. Serum total cholesterol and leptin were significantly decreased in isoflavone group, compared with the OVX group. The mRNA expression of liver fatty acid synthase (FAS) in the OVX group was significantly higher than that in sham-operated group, while this difference was not observed in the isoflavone group. The mRNA expression of liver hormone-sensitive lipase (HSL) in the OVX rats tended to be lower than that in the sham-operated rats. Furthermore, a large amount of isoflavone maintained the mRNA expression at a sham level. Conclusion lsoflavone may prevent obesity induced by ovariectomy with a high-fat diet, in part by modulating gene expression related to lipid metabolism.

  18. Histidine phosphorylation relieves copper inhibition in the mammalian potassium channel KCa3.1.

    Science.gov (United States)

    Srivastava, Shekhar; Panda, Saswati; Li, Zhai; Fuhs, Stephen R; Hunter, Tony; Thiele, Dennis J; Hubbard, Stevan R; Skolnik, Edward Y

    2016-01-01

    KCa2.1, KCa2.2, KCa2.3 and KCa3.1 constitute a family of mammalian small- to intermediate-conductance potassium channels that are activated by calcium-calmodulin. KCa3.1 is unique among these four channels in that activation requires, in addition to calcium, phosphorylation of a single histidine residue (His358) in the cytoplasmic region, by nucleoside diphosphate kinase-B (NDPK-B). The mechanism by which KCa3.1 is activated by histidine phosphorylation is unknown. Histidine phosphorylation is well characterized in prokaryotes but poorly understood in eukaryotes. Here, we demonstrate that phosphorylation of His358 activates KCa3.1 by antagonizing copper-mediated inhibition of the channel. Furthermore, we show that activated CD4(+) T cells deficient in intracellular copper exhibit increased KCa3.1 histidine phosphorylation and channel activity, leading to increased calcium flux and cytokine production. These findings reveal a novel regulatory mechanism for a mammalian potassium channel and for T-cell activation, and highlight a unique feature of histidine versus serine/threonine and tyrosine as a regulatory phosphorylation site. PMID:27542194

  19. Time-restricted feeding reduces adiposity in mice fed a high-fat diet.

    Science.gov (United States)

    Sundaram, Sneha; Yan, Lin

    2016-06-01

    Disruption of the circadian rhythm contributes to obesity. This study tested the hypothesis that time-restricted feeding (TRF) reduces high-fat diet-induced increase in adiposity. Male C57BL/6 mice were fed the AIN93G or the high-fat diet ad libitum (ad lib); TRF of the high-fat diet for 12 or 8hours during the dark cycle was initiated when high-fat diet-fed mice exhibited significant increases in body weight. Energy intake of the TRF 12-hour group was not different from that of the high-fat ad lib group, although that of the TRF 8-hour group was slightly but significantly lower. Restricted feeding of the high-fat diet reduced body fat mass and body weight compared with mice fed the high-fat diet ad lib. There were no differences in respiratory exchange ratio (RER) among TRF and high-fat ad lib groups, but the RER of these groups was lower than that of the AIN93G group. Energy expenditure of the TRF groups was slightly but significantly lower than that of the high-fat ad lib group. Plasma concentrations of ghrelin were increased in TRF groups compared with both AIN93G and high-fat ad lib groups. Elevations of plasma concentrations of insulin, leptin, monocyte chemoattractant protein-1, and tissue inhibitor metalloproteinase-1 by high-fat ad lib feeding were reduced by TRF to the levels of mice fed the AIN93G diet. In conclusion, TRF during the dark cycle reduces high-fat diet-induced increases in adiposity and proinflammatory cytokines. These results indicate that circadian timing of food intake may prevent obesity and abate obesity-related metabolic disturbance. PMID:27188906

  20. Selective inhibition of phosphodiesterase 1 relaxes urinary bladder smooth muscle: role for ryanodine receptor-mediated BK channel activation

    OpenAIRE

    Xin, Wenkuan; Soder, Rupal P; Cheng, Qiuping; Eric S. Rovner; Petkov, Georgi V.

    2012-01-01

    The large conductance voltage- and Ca2+-activated K+ (BK) channel is a major regulator of detrusor smooth muscle (DSM) excitability and contractility. Recently, we showed that nonselective phosphodiesterase (PDE) inhibition reduces guinea pig DSM excitability and contractility by increasing BK channel activity. Here, we investigated how DSM excitability and contractility changes upon selective inhibition of PDE type 1 (PDE1) and the underlying cellular mechanism involving ryanodine receptors ...

  1. [Inhibition of oxygen free radicals in potassium channels of cardiac myocytes and the action of salvianolic acid A].

    Science.gov (United States)

    Bao, G

    1993-10-01

    By using the patch clamp technique, the effect of oxygen free radicals on the single potassium channels of cardiac papillary muscle cells were studied, as well as the action of salvianolic acid A. It was found that xanthane-xanthane oxidase generated oxygen free radicals could apparently inhibited the unitary currents of the single potassium channel activity. This inhibition was reversed by salvianolic acid A, which is an effective component extracted from Salvia miltiorrhiza. PMID:8168213

  2. Proton Dependent Inhibition of the Cardiac Sodium Channel Nav1.5 by Ranolazine

    Directory of Open Access Journals (Sweden)

    PeterCRuben

    2013-06-01

    Full Text Available Ranolazine is clinically approved for treatment of angina pectoris and is a potential candidate for antiarrhythmic, antiepileptic and analgesic applications. These therapeutic effects of ranolazine hinge on its ability to inhibit persistent or late Na+ currents in a variety of voltage-gated sodium channels. Extracellular acidosis, typical of ischemic events, may alter the efficiency of drug/channel interactions. In this study, we examined pH modulation of ranolazine’s interaction with the cardiac sodium channel, Nav1.5. We performed whole-cell path clamp experiments at extracellular pH 7.4 and 6.0 on Nav1.5 transiently expressed in HEK293 cell line. Consistent with previous studies, we found that ranolazine induced a stable conformational state in the cardiac sodium channel with onset/recovery kinetics and voltage-dependence resembling intrinsic slow inactivation. This interaction diminished the availability of the channels in a voltage- and use-dependent manner. Low extracellular pH impaired inactivation states leading to an increase in late Na+ currents. Ranolazine interaction with the channel was also slowed 4-5 fold. However, ranolazine restored the voltage-dependent steady-state availability profile, thereby reducing window/persistent currents at pH 6.0 in a manner comparable to pH 7.4. These results suggest that ranolazine is effective at therapeutically relevant concentrations (10µM, in acidic extracellular pH, where it compensates for impaired native slow inactivation.

  3. High-fat diet-induced obesity alters nitric oxide-mediated neuromuscular transmission and smooth muscle excitability in the mouse distal colon.

    Science.gov (United States)

    Bhattarai, Yogesh; Fried, David; Gulbransen, Brian; Kadrofske, Mark; Fernandes, Roxanne; Xu, Hui; Galligan, James

    2016-08-01

    We tested the hypothesis that colonic enteric neurotransmission and smooth muscle cell (SMC) function are altered in mice fed a high-fat diet (HFD). We used wild-type (WT) mice and mice lacking the β1-subunit of the BK channel (BKβ1 (-/-)). WT mice fed a HFD had increased myenteric plexus oxidative stress, a 28% decrease in nitrergic neurons, and a 20% decrease in basal nitric oxide (NO) levels. Circular muscle inhibitory junction potentials (IJPs) were reduced in HFD WT mice. The NO synthase inhibitor nitro-l-arginine (NLA) was less effective at inhibiting relaxations in HFD compared with control diet (CD) WT mice (11 vs. 37%, P < 0.05). SMCs from HFD WT mice had depolarized membrane potentials (-47 ± 2 mV) and continuous action potential firing compared with CD WT mice (-53 ± 2 mV, P < 0.05), which showed rhythmic firing. SMCs from HFD or CD fed BKβ1 (-/-) mice fired action potentials continuously. NLA depolarized membrane potential and caused continuous firing only in SMCs from CD WT mice. Sodium nitroprusside (NO donor) hyperpolarized membrane potential and changed continuous to rhythmic action potential firing in SMCs from HFD WT and BKβ1 (-/-) mice. Migrating motor complexes were disrupted in colons from BKβ1 (-/-) mice and HFD WT mice. BK channel α-subunit protein and β1-subunit mRNA expression were similar in CD and HFD WT mice. We conclude that HFD-induced obesity disrupts inhibitory neuromuscular transmission, SMC excitability, and colonic motility by promoting oxidative stress, loss of nitrergic neurons, and SMC BK channel dysfunction. PMID:27288421

  4. Effects on atrial fibrillation in aged hypertensive rats by Ca(2+)-activated K(+) channel inhibition

    DEFF Research Database (Denmark)

    Diness, Jonas Goldin; Skibsbye, Lasse; Jespersen, Thomas;

    2011-01-01

    We have shown previously that inhibition of small conductance Ca(2+)-activated K(+) (SK) channels is antiarrhythmic in models of acutely induced atrial fibrillation (AF). These models, however, do not take into account that AF derives from a wide range of predisposing factors, the most prevalent...... being hypertension. In this study we assessed the effects of two different SK channel inhibitors, NS8593 and UCL1684, in aging, spontaneously hypertensive rats to examine their antiarrhythmic properties in a setting of hypertension-induced atrial remodeling. Male spontaneously hypertensive rats and the...... normotensive Wistar-Kyoto rat strain were divided in 2×3 groups of animals aged 3, 8, and 11 months, respectively. The animals were randomly assigned to treatment with NS8593, UCL1684, or vehicle, and open chest in vivo experiments including burst pacing-induced AF were performed. The aging spontaneously...

  5. Thylakoids suppress appetite by increasing cholecystokinin resulting in lower food intake and body weight in high-fat fed mice

    DEFF Research Database (Denmark)

    Köhnke, Rickard; Lindqvist, Andreas; Göransson, Nathanael;

    2009-01-01

    Thylakoids are membranes isolated from plant chloroplasts which have previously been shown to inhibit pancreatic lipase/colipase catalysed hydrolysis of fat in vitro and induce short-term satiety in vivo. The purpose of the present study was to examine if dietary supplementation of thylakoids could...... compared with the high-fat fed control mice. Reduced serum glucose, serum triglyceride and serum free fatty acid levels were found in the thylakoid-treated animals. The satiety hormone cholecystokinin was elevated, suggesting this hormone mediates satiety. Leptin levels were reduced, reflecting a decreased...

  6. Alcohol and high fat induced chronic pancreatitis: TRPV4 antagonist reduces hypersensitivity.

    Science.gov (United States)

    Zhang, L P; Kline, R H; Deevska, G; Ma, F; Nikolova-Karakashian, M; Westlund, K N

    2015-12-17

    The pathogenesis of pain in chronic pancreatitis is poorly understood, and its treatment can be a major clinical challenge. Surgical and other invasive methods have variable outcomes that can be unsatisfactory. Therefore, there is a great need for further discovery of the pathogenesis of pancreatitis pain and new therapeutic targets. Human and animal studies indicate a critical role for oxidative stress and activation of transient receptor potential (TRP) cation channel subfamily members TRPV1 and TRPA1 on pancreatic nociceptors in sensitization mechanisms that result in pain. However, the in vivo role of transient receptor potential cation channel subfamily V member 4 (TRPV4) in chronic pancreatitis needs further evaluation. The present study characterized a rat alcohol/high fat diet (AHF)-induced chronic pancreatitis model with hypersensitivity, fibrotic pathology, and fat vacuolization consistent with the clinical syndrome. The rats with AHF-induced pancreatitis develop referred visceral pain-like behaviors, i.e. decreased hindpaw mechanical thresholds and shortened abdominal and hindpaw withdrawal latency to heat. In this study, oxidative stress was characterized as well as the role of TRPV4 in chronic visceral hypersensitivity. Lipid peroxidase and oxidative stress were indicated by increased plasma thiobarbituric acid reactive substances (TBARS) and diminished pancreatic manganese superoxide dismutase (MnSOD). The secondary sensitization associated with AHF-induced pancreatitis was effectively alleviated by the TRPV4 antagonist, HC 067047. Similarity of the results to those with the peripherally restricted μ-opiate receptor agonist, loperamide, suggested TRPV4 channel activated peripheral sensitization. This study using a reliable model that provides pre-clinical correlates of human chronic pancreatitis provides further evidence that TRPV4 channel is a potential therapeutic target for treatment of pancreatitis pain. PMID:26480812

  7. Gabapentin inhibits high-threshold calcium channel currents in cultured rat dorsal root ganglion neurones

    OpenAIRE

    Sutton, K G; Martin, D. J.; Pinnock, R. D.; Lee, K.; Scott, R. H.

    2002-01-01

    This study examined the action of gabapentin (gabapentin,1-(aminomethyl) cyclohexane acetic acid (Neurontin®)) on voltage-gated calcium (Ca2+) channel influx recorded in cultured rat dorsal root ganglion (DRG) neurones.Voltage-gated Ca2+ influx was monitored using both fura-2 based fluorescence Ca2+ imaging and the whole-cell patch clamp technique.Imaging of intracellular Ca2+ transients revealed that gabapentin inhibited KCl (30 mM)-evoked voltage-dependent Ca2+ influx. Both the duration for...

  8. Inhibition of G protein-activated inwardly rectifying K+ channels by fluoxetine (Prozac)

    OpenAIRE

    Kobayashi, Toru; Washiyama, Kazuo; Ikeda, Kazutaka

    2003-01-01

    The effects of fluoxetine, a commonly used antidepressant drug, on G protein-activated inwardly rectifying K+ channels (GIRK, Kir3) were investigated using Xenopus oocyte expression assays.In oocytes injected with mRNAs for GIRK1/GIRK2, GIRK2 or GIRK1/GIRK4 subunits, fluoxetine reversibly reduced inward currents through the basal GIRK activity. The inhibition by fluoxetine showed a concentration-dependence, a weak voltage-dependence and a slight time-dependence with a predominant effect on th...

  9. Marked hyperleptinemia after high-fat diet associated with severe glucose intolerance in mice

    NARCIS (Netherlands)

    Ahren, B.; Scheurink, A.J.W.

    1998-01-01

    We asked whether the likelihood for mice of the C57BL/6J strain to develop glucose intolerance when fed a high-fat diet is related to the increase in circulating levels of leptin or free fatty acids (FFA). We therefore administered a high-fat diet (58% fat) or a control diet (11% fat) for 1.5 years.

  10. Caspase-1 as a central regulator of high fat diet-induced non-alcoholic steatohepatitis.

    Directory of Open Access Journals (Sweden)

    Laura J Dixon

    Full Text Available Nonalcoholic steatohepatitis (NASH is associated with caspase activation. However, a role for pro-inflammatory caspases or inflammasomes has not been explored in diet-induced liver injury. Our aims were to examine the role of caspase-1 in high fat-induced NASH. C57BL/6 wild-type and caspase 1-knockout (Casp1(-/- mice were placed on a 12-week high fat diet. Wild-type mice on the high fat diet increased hepatic expression of pro-caspase-1 and IL-1β. Both wild-type and Casp1(-/- mice on the high fat diet gained more weight than mice on a control diet. Hepatic steatosis and TG levels were increased in wild-type mice on high fat diet, but were attenuated in the absence of caspase-1. Plasma cholesterol and free fatty acids were elevated in wild-type, but not Casp1(-/- mice, on high fat diet. ALT levels were elevated in both wild-type and Casp1(-/- mice on high fat diet compared to control. Hepatic mRNA expression for genes associated with lipogenesis was lower in Casp1(-/- mice on high fat diet compared to wild-type mice on high fat diet, while genes associated with fatty acid oxidation were not affected by diet or genotype. Hepatic Tnfα and Mcp-1 mRNA expression was increased in wild-type mice on high fat diet, but not in Casp1(-/- mice on high fat diet. αSMA positive cells, Sirius red staining, and Col1α1 mRNA were increased in wild-type mice on high fat diet compared to control. Deficiency of caspase-1 prevented those increases. In summary, the absence of caspase-1 ameliorates the injurious effects of high fat diet-induced obesity on the liver. Specifically, mice deficient in caspase-1 are protected from high fat-induced hepatic steatosis, inflammation and early fibrogenesis. These data point to the inflammasome as an important therapeutic target for NASH.

  11. Mutant connexin 50 (S276F) inhibits channel and hemichannel functions inducing cataract

    Indian Academy of Sciences (India)

    Yuanyuan Liu; Chen Qiao; Tanwei Wei; Fang Zheng; Shuren Guo; Qiang Chen; Ming Yan; Xin Zhou

    2015-06-01

    This study was designed to detect the expression, detergent resistance, subcellular localization, and channel and hemichannel functions of mutant Cx50 to understand the forming mechanism for inducing congenital cataract by a novel mutation p.S276F in connexin 50 (Cx50) reported previously by us. HeLa and human lens epithelial (HLE) cells were transfected with wild-type Cx50 and mutant Cx50 (S276F). We examined the functional characteristics of mutant Cx50 (S276F) in comparison with those of wild-type Cx50 using immunoblot, confocal fluorescence microscopy, dye transfer analysis and dye uptake assay. The mutant and wild-type Cx50 were expressed in equal levels and could efficiently localize to the plasma membrane without transportation and assembly problems. Scrape loading dye transfer was significantly evident in cells transfected with wild-type Cx50 compared to those in cells transfected with mutant Cx50 and cotransfected with wild-type and mutant Cx50. The dye uptake was found to be significantly lower in cells transfected with mutant Cx50 than in cells transfected with wild-type Cx50 and cells cotransfected with wild-type and mutant Cx50. The transfected HeLa and HLE cell lines showed similar performance in all the experiments. These results indicated that the mutant Cx50 (S276F) might inhibit the function of gap junction channel in a dominant negative manner, but inhibit the hemichannel function in a recessive negative manner.

  12. Stereoselective inhibition of thromboxane-induced coronary vasoconstriction by 1,4-dihydropyridine calcium channel antagonists

    International Nuclear Information System (INIS)

    The biological activity of the (+)-S- and (-)-R-enantiomers of niguldipine, of the (-)-S- and (+)-R-enantiomers of felodipine and nitrendipine, and of rac-nisoldipine and rac-nimodipine was investigated in vitro and in vivo. Inhibition of coronary vasoconstriction due to the thromboxane A2 (TxA2)-mimetic U-46619 in guinea pig Langendorff hearts, displacement of (+)-[3H]isradipine from calcium channel binding sites of guinea pig skeletal muscle T-tubule membranes, and blood pressure reduction in spontaneously hypertensive rats were determined. The enantiomers were obtained by stereoselective synthesis. Cross-contamination was less than 0.5% for both S- and R-enantiomers of niguldipine and nitrendipine and less than 1% for those of felodipine. From the doses necessary for a 50% inhibition of coronary vasoconstriction, stereoselectivity ratios for (+)-(S)-/(-)-(R)-niguldipine, (-)-(S)-/(+)-(R)-felodipine, and (-)-(S)-/(+)-(R)-nitrendipine of 28, 13, and 7, respectively, were calculated. The potency ratio rac-nisoldipine/rac-nimodipine was 3.5. Ratios obtained from binding experiments and antihypertensive activity were (+)-(S)-/(-)-(R)-niguldipine = 45 and 35, (-)-(S)-/(+)-(R)-felodipine = 12 and 13, (-)-(S)-/(+)-(R)-nitrendipine = 8 and 8, and rac-nisoldipine/rac-nimodipine = 8 and 7, respectively. Highly significant correlations were found between the in vitro potency of the substances to prevent U-46619-induced coronary vasoconstriction and their affinity for calcium channel binding sites as well as their antihypertensive activity

  13. Gambierol inhibition of voltage-gated potassium channels augments spontaneous Ca2+ oscillations in cerebrocortical neurons.

    Science.gov (United States)

    Cao, Zhengyu; Cui, Yanjun; Busse, Eric; Mehrotra, Suneet; Rainier, Jon D; Murray, Thomas F

    2014-09-01

    Gambierol is a marine polycyclic ether toxin produced by the marine dinoflagellate Gambierdiscus toxicus and is a member of the ciguatoxin toxin family. Gambierol has been demonstrated to be either a low-efficacy partial agonist/antagonist of voltage-gated sodium channels or a potent blocker of voltage-gated potassium channels (Kvs). Here we examined the influence of gambierol on intact cerebrocortical neurons. We found that gambierol produced both a concentration-dependent augmentation of spontaneous Ca(2+) oscillations, and an inhibition of Kv channel function with similar potencies. In addition, an array of selective as well as universal Kv channel inhibitors mimicked gambierol in augmenting spontaneous Ca(2+) oscillations in cerebrocortical neurons. These data are consistent with a gambierol blockade of Kv channels underlying the observed increase in spontaneous Ca(2+) oscillation frequency. We also found that gambierol produced a robust stimulation of phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2). Gambierol-stimulated ERK1/2 activation was dependent on both inotropic [N-methyl-d-aspartate (NMDA)] and type I metabotropic glutamate receptors (mGluRs) inasmuch as MK-801 [NMDA receptor inhibitor; (5S,10R)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate], S-(4)-CGP [S-(4)-carboxyphenylglycine], and MTEP [type I mGluR inhibitors; 3-((2-methyl-4-thiazolyl)ethynyl) pyridine] attenuated the response. In addition, 2-aminoethoxydiphenylborane, an inositol 1,4,5-trisphosphate receptor inhibitor, and U73122 (1-[6-[[(17b)-3-methoxyestra-1,3,5(10)-trien-17-yl]amino]hexyl]-1H-pyrrole-2,5-dione), a phospholipase C inhibitor, both suppressed gambierol-induced ERK1/2 activation, further confirming the role of type I mGluR-mediated signaling in the observed ERK1/2 activation. Finally, we found that gambierol produced a concentration-dependent stimulation of neurite outgrowth that was mimicked by 4-aminopyridine, a universal

  14. Natural and synthetic modulators of SK (Kca2) potassium channels inhibit magnesium-dependent activity of the kinase-coupled cation channel TRPM7

    Science.gov (United States)

    Chubanov, V; Mederos y Schnitzler, M; Meißner, M; Schäfer, S; Abstiens, K; Hofmann, T; Gudermann, T

    2012-01-01

    BACKGROUND AND PURPOSE Transient receptor potential cation channel subfamily M member 7 (TRPM7) is a bifunctional protein comprising a TRP ion channel segment linked to an α-type protein kinase domain. TRPM7 is essential for proliferation and cell growth. Up-regulation of TRPM7 function is involved in anoxic neuronal death, cardiac fibrosis and tumour cell proliferation. The goal of this work was to identify non-toxic inhibitors of the TRPM7 channel and to assess the effect of blocking endogenous TRPM7 currents on the phenotype of living cells. EXPERIMENTAL APPROACH We developed an aequorin bioluminescence-based assay of TRPM7 channel activity and performed a hypothesis-driven screen for inhibitors of the channel. The candidates identified were further assessed electrophysiologically and in cell biological experiments. KEY RESULTS TRPM7 currents were inhibited by modulators of small conductance Ca2+-activated K+ channels (KCa2.1–2.3; SK) channels, including the antimalarial plant alkaloid quinine, CyPPA, dequalinium, NS8593, SKA31 and UCL 1684. The most potent compound NS8593 (IC50 1.6 µM) specifically targeted TRPM7 as compared with other TRP channels, interfered with Mg2+-dependent regulation of TRPM7 channel and inhibited the motility of cultured cells. NS8593 exhibited full and reversible block of native TRPM7-like currents in HEK 293 cells, freshly isolated smooth muscle cells, primary podocytes and ventricular myocytes. CONCLUSIONS AND IMPLICATIONS This study reveals a tight overlap in the pharmacological profiles of TRPM7 and KCa2.1–2.3 channels. NS8593 acts as a negative gating modulator of TRPM7 and is well-suited to study functional features and cellular roles of endogenous TRPM7. PMID:22242975

  15. Barbiturates inhibit ATP-K+ channels and voltage-activated currents in CRI-G1 insulin-secreting cells.

    OpenAIRE

    Kozlowski, R. Z.; Ashford, M. L.

    1991-01-01

    1. Patch-clamp recording techniques were used to examine the effects of barbiturates upon the ATP-K+ channel, and voltage-activated channels present in the plasma membrane of CRI-G1 insulin-secreting cells. 2. Thiopentone inhibited ATP-K+ channel activity when applied to cell-attached patches or the intracellular or extracellular surface of cell-free patches. Secobarbitone and pentobarbitone were also effective inhibitors of ATP-K+ channels in cell-free patches, whereas phenobarbitone was ine...

  16. Inhibition of herpes simplex virus type 1 entry by chloride channel inhibitors tamoxifen and NPPB

    International Nuclear Information System (INIS)

    Highlights: • We analyze the anti-HSV potential of chloride channel inhibitors. • Tamoxifen and NPPB show anti-HSV-1 and anti-ACV-resistant HSV-1 activities. • HSV-1 infection induces intracellular chloride concentration increasing. • Tamoxifen and NPPB inhibit HSV-1 early infection. • Tamoxifen and NPPB prevent the fusion process of HSV-1. - Abstract: Herpes simplex virus type 1 (HSV-1) infection is very common worldwide and can cause significant health problems from periodic skin and corneal lesions to encephalitis. Appearance of drug-resistant viruses in clinical therapy has made exploring novel antiviral agents emergent. Here we show that chloride channel inhibitors, including tamoxifen and 5-nitro-2-(3-phenyl-propylamino) benzoic acid (NPPB), exhibited extensive antiviral activities toward HSV-1 and ACV-resistant HSV viruses. HSV-1 infection induced chloride ion influx while treatment with inhibitors reduced the increase of intracellular chloride ion concentration. Pretreatment or treatment of inhibitors at different time points during HSV-1 infection all suppressed viral RNA synthesis, protein expression and virus production. More detailed studies demonstrated that tamoxifen and NPPB acted as potent inhibitors of HSV-1 early entry step by preventing viral binding, penetration and nuclear translocation. Specifically the compounds appeared to affect viral fusion process by inhibiting virus binding to lipid rafts and interrupting calcium homeostasis. Taken together, the observation that tamoxifen and NPPB can block viral entry suggests a stronger potential for these compounds as well as other ion channel inhibitors in antiviral therapy against HSV-1, especially the compound tamoxifen is an immediately actionable drug that can be reused for treatment of HSV-1 infections

  17. Inhibition of herpes simplex virus type 1 entry by chloride channel inhibitors tamoxifen and NPPB

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Kai [Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou (China); College of Life Science and Technology, Jinan University, Guangzhou (China); Chen, Maoyun [Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou (China); College of pharmacy, Jinan University, Guangzhou (China); Xiang, Yangfei; Ma, Kaiqi [Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou (China); Jin, Fujun [Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou (China); College of pharmacy, Jinan University, Guangzhou (China); Wang, Xiao [School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006 (China); Wang, Xiaoyan; Wang, Shaoxiang [Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou (China); Wang, Yifei, E-mail: twang-yf@163.com [Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou (China)

    2014-04-18

    Highlights: • We analyze the anti-HSV potential of chloride channel inhibitors. • Tamoxifen and NPPB show anti-HSV-1 and anti-ACV-resistant HSV-1 activities. • HSV-1 infection induces intracellular chloride concentration increasing. • Tamoxifen and NPPB inhibit HSV-1 early infection. • Tamoxifen and NPPB prevent the fusion process of HSV-1. - Abstract: Herpes simplex virus type 1 (HSV-1) infection is very common worldwide and can cause significant health problems from periodic skin and corneal lesions to encephalitis. Appearance of drug-resistant viruses in clinical therapy has made exploring novel antiviral agents emergent. Here we show that chloride channel inhibitors, including tamoxifen and 5-nitro-2-(3-phenyl-propylamino) benzoic acid (NPPB), exhibited extensive antiviral activities toward HSV-1 and ACV-resistant HSV viruses. HSV-1 infection induced chloride ion influx while treatment with inhibitors reduced the increase of intracellular chloride ion concentration. Pretreatment or treatment of inhibitors at different time points during HSV-1 infection all suppressed viral RNA synthesis, protein expression and virus production. More detailed studies demonstrated that tamoxifen and NPPB acted as potent inhibitors of HSV-1 early entry step by preventing viral binding, penetration and nuclear translocation. Specifically the compounds appeared to affect viral fusion process by inhibiting virus binding to lipid rafts and interrupting calcium homeostasis. Taken together, the observation that tamoxifen and NPPB can block viral entry suggests a stronger potential for these compounds as well as other ion channel inhibitors in antiviral therapy against HSV-1, especially the compound tamoxifen is an immediately actionable drug that can be reused for treatment of HSV-1 infections.

  18. High-fat diet and glucocorticoid treatment cause hyperglycemia associated with adiponectin receptor alterations

    Directory of Open Access Journals (Sweden)

    Oller do Nascimento Cláudia

    2011-01-01

    Full Text Available Abstract Background Adiponectin is the most abundant plasma protein synthesized for the most part in adipose tissue, and it is an insulin-sensitive hormone, playing a central role in glucose and lipid metabolism. In addition, it increases fatty acid oxidation in the muscle and potentiates insulin inhibition of hepatic gluconeogenesis. Two adiponectin receptors have been identified: AdipoR1 is the major receptor expressed in skeletal muscle, whereas AdipoR2 is mainly expressed in liver. Consumption of high levels of dietary fat is thought to be a major factor in the promotion of obesity and insulin resistance. Excessive levels of cortisol are characterized by the symptoms of abdominal obesity, hypertension, glucose intolerance or diabetes and dyslipidemia; of note, all of these features are shared by the condition of insulin resistance. Although it has been shown that glucocorticoids inhibit adiponectin expression in vitro and in vivo, little is known about the regulation of adiponectin receptors. The link between glucocorticoids and insulin resistance may involve the adiponectin receptors and adrenalectomy might play a role not only in regulate expression and secretion of adiponectin, as well regulate the respective receptors in several tissues. Results Feeding of a high-fat diet increased serum glucose levels and decreased adiponectin and adipoR2 mRNA expression in subcutaneous and retroperitoneal adipose tissues, respectively. Moreover, it increased both adipoR1 and adipoR2 mRNA levels in muscle and adipoR2 protein levels in liver. Adrenalectomy combined with the synthetic glucocorticoid dexamethasone treatment resulted in increased glucose and insulin levels, decreased serum adiponectin levels, reduced adiponectin mRNA in epididymal adipose tissue, reduction of adipoR2 mRNA by 7-fold in muscle and reduced adipoR1 and adipoR2 protein levels in muscle. Adrenalectomy alone increased adiponectin mRNA expression 3-fold in subcutaneous adipose

  19. K-channels inhibited by hydrogen peroxide mediate abscisic acid signaling in Vicia guard cells

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A number of studies show that environmental stress conditions increase abscisic acid (ABA) and hydrogen peroxide (H2O2) levels in plant cells. Despite this central role of ABA in altering stomatal aperture by regulating guard cell ion transport, little is known concerning the relationship between ABA and H2O2 in signal transduction leading to stomatal movement. Epidermal strip bioassay illustrated that ABA-inhibited stomatal opening and ABA-induced stomatal closure were abolished partly by externally added catalase (CAT) or diphenylene iodonium (DPI), which are a H2O2 scavenger and a NADPH oxidase inhibitor respectively. In contrast, internally added CAT or DPI nearly completely or partly reversed ABA-induced closure in half-stoma. Consistent with these results, whole-cell patch-clamp analysis showed that intracellular application of CAT or DPI partly abolished ABA-inhibited inward K+ current across the plasma membrane of guard cells. H2O2 mimicked ABA to inhibit inward K+ current, an effect which was reversed by the addition of ascorbic acid (Vc) in patch clamping micropipettes. These results suggested that H2O2 mediated ABA-induced stomatal movement by targeting inward K+ channels at plasma membrane.

  20. The Korean Mistletoe (Viscum album coloratum Extract Has an Antiobesity Effect and Protects against Hepatic Steatosis in Mice with High-Fat Diet-Induced Obesity

    Directory of Open Access Journals (Sweden)

    Hoe-Yune Jung

    2013-01-01

    Full Text Available This study investigates the inhibitory effects of Korean mistletoe extract (KME on adipogenic factors in 3T3-L1 cells and obesity and nonalcoholic fatty liver disease (NAFLD in mice fed a high-fat diet. Male C57Bl/6 mice fed a high-fat diet were treated with KME (3 g/kg/day for 15 weeks for the antiobesity and NAFLD experiments. Body weight and daily food intake were measured regularly during the experimental period. The epididymal pad was measured and liver histology was observed. The effects of KME on thermogenesis and endurance capacity were measured. The effects of KME on adipogenic factors were examined in 3T3-L1 cells. Body and epididymal fat pad weights were reduced in KME-treated mice, and histological examination showed an amelioration of fatty liver in KME-treated mice, without an effect on food consumption. KME potently induces mitochondrial activity by activating thermogenesis and improving endurance capacity. KME also inhibited adipogenic factors in vitro. These results demonstrate the inhibitory effects of KME on obesity and NAFLD in mice fed a high-fat diet. The effects appear to be mediated through an enhanced mitochondrial activity. Therefore, KME may be an effective therapeutic candidate for treating obesity and fatty liver caused by a high-fat diet.

  1. High fat diet promotes achievement of peak bone mass in young rats

    Energy Technology Data Exchange (ETDEWEB)

    Malvi, Parmanand; Piprode, Vikrant; Chaube, Balkrishna; Pote, Satish T. [National Centre for Cell Science, Savitribai Phule Pune University Campus, Ganeshkhind, Pune 411 007 (India); Mittal, Monika; Chattopadhyay, Naibedya [Division of Endocrinology and Center for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI), CSIR-Central Drug Research Institute, Jankipuram Extension, Sitapur Road, Lucknow 226 031 (India); Wani, Mohan R. [National Centre for Cell Science, Savitribai Phule Pune University Campus, Ganeshkhind, Pune 411 007 (India); Bhat, Manoj Kumar, E-mail: manojkbhat@nccs.res.in [National Centre for Cell Science, Savitribai Phule Pune University Campus, Ganeshkhind, Pune 411 007 (India)

    2014-12-05

    Highlights: • High fat diet helps in achieving peak bone mass at younger age. • Shifting from high fat to normal diet normalizes obese parameters. • Bone parameters are sustained even after withdrawal of high fat diet. - Abstract: The relationship between obesity and bone is complex. Epidemiological studies demonstrate positive as well as negative correlation between obesity and bone health. In the present study, we investigated the impact of high fat diet-induced obesity on peak bone mass. After 9 months of feeding young rats with high fat diet, we observed obesity phenotype in rats with increased body weight, fat mass, serum triglycerides and cholesterol. There were significant increases in serum total alkaline phosphatase, bone mineral density and bone mineral content. By micro-computed tomography (μ-CT), we observed a trend of better trabecular bones with respect to their microarchitecture and geometry. This indicated that high fat diet helps in achieving peak bone mass and microstructure at younger age. We subsequently shifted rats from high fat diet to normal diet for 6 months and evaluated bone/obesity parameters. It was observed that after shifting rats from high fat diet to normal diet, fat mass, serum triglycerides and cholesterol were significantly decreased. Interestingly, the gain in bone mineral density, bone mineral content and trabecular bone parameters by HFD was retained even after body weight and obesity were normalized. These results suggest that fat rich diet during growth could accelerate achievement of peak bone mass that is sustainable even after withdrawal of high fat diet.

  2. High fat diet promotes achievement of peak bone mass in young rats

    International Nuclear Information System (INIS)

    Highlights: • High fat diet helps in achieving peak bone mass at younger age. • Shifting from high fat to normal diet normalizes obese parameters. • Bone parameters are sustained even after withdrawal of high fat diet. - Abstract: The relationship between obesity and bone is complex. Epidemiological studies demonstrate positive as well as negative correlation between obesity and bone health. In the present study, we investigated the impact of high fat diet-induced obesity on peak bone mass. After 9 months of feeding young rats with high fat diet, we observed obesity phenotype in rats with increased body weight, fat mass, serum triglycerides and cholesterol. There were significant increases in serum total alkaline phosphatase, bone mineral density and bone mineral content. By micro-computed tomography (μ-CT), we observed a trend of better trabecular bones with respect to their microarchitecture and geometry. This indicated that high fat diet helps in achieving peak bone mass and microstructure at younger age. We subsequently shifted rats from high fat diet to normal diet for 6 months and evaluated bone/obesity parameters. It was observed that after shifting rats from high fat diet to normal diet, fat mass, serum triglycerides and cholesterol were significantly decreased. Interestingly, the gain in bone mineral density, bone mineral content and trabecular bone parameters by HFD was retained even after body weight and obesity were normalized. These results suggest that fat rich diet during growth could accelerate achievement of peak bone mass that is sustainable even after withdrawal of high fat diet

  3. High-fat-induced intestinal permeability dysfunction associated with altered fecal bile acids

    Institute of Scientific and Technical Information of China (English)

    Lotta K Stenman; Reetta Holma; Riitta Korpela

    2012-01-01

    AIM:To investigate whether high-fat-feeding is associated with increased intestinal permeability via alterations in bile acid metabolism.METHODS:Male C57B1/6J mice were fed on a high-fat (n =26) or low-fat diet (n =24) for 15 wk.Intestinal permeability was measured from duodenum,jejunum,ileum and colon in an Ussing chamber system using 4 kDa FITC-labeled dextran as an indicator.Fecal bile acids were analyzed with gas chromatography.Segments of jejunum and colon were analyzed for the expression of farnesoid X receptor (FXR) and tumor necrosis factor (TNF).RESULTS:Intestinal permeability was significantly increased by high-fat feeding in jejunum (median 0.334 for control vs 0.393 for high-fat,P =0.03) and colon (0.335 for control vs 0.433 for high-fat,P =0.01),but not in duodenum or ileum.The concentration of nearly all identified bile acids was significantly increased by high-fat feeding (P < 0.001).The proportion of ursodeoxycholic acid (UDCA) in all bile acids was decreased (1.4% ± 0.1% in high-fat vs 2.8% ± 0.3% in controls,P < 0.01) and correlated inversely with intestinal permeability (r =-0.72,P =0.01).High-fat feeding also increased jejunal FXR expression,as well as TNF expression along the intestine,especially in the colon.CONCLUSION:High-fat-feeding increased intestinal permeability,perhaps by a mechanism related to bile acid metabolism,namely a decreased proportion of fecal UDCA and increased FXR expression.

  4. Like Extinction, Latent Inhibition of Conditioned Fear in Mice Is Blocked by Systemic Inhibition of L-Type Voltage-Gated Calcium Channels

    Science.gov (United States)

    Blouin, Ashley M.; Cain, Chris K.; Barad, Mike

    2004-01-01

    Having recently shown that extinction of conditioned fear depends on L-type voltage-gated calcium channels (LVGCCs), we have been seeking other protocols that require this unusual induction mechanism. We tested latent inhibition (LI) of fear, because LI resembles extinction except that cue exposures precede, rather than follow, cue-shock pairing.…

  5. Effects of four Bifidobacteria on obesity in high-fat diet induced rats

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM:To compare the effects of four Bifidobacteria strains(Bifidobacteria L66-5,L75-4,M13-4 and FS31-12,originated from normal human intestines) on weight gain,lipid metabolism,glucose metabolism in an obese murine model induced by high-fat diet.METHODS:Forty-eight Sprague-Dawley rats were randomly divided into six groups.Control group received standard chow,model group received high-fat diet,and intervention groups received high-fat diet added with different Bifidobacteria strains isolated from healthy volu...

  6. The model of rat lipid metabolism disorder induced by chronic stress accompanying high-fat-diet

    OpenAIRE

    Shaodong Chen; Jing Li; Haihong Zhou; Manting Lin; Yihua Liu

    2011-01-01

    Abstract Objective To develop an animal model of Lipid Metabolism Disorder, which conforms to human clinical characteristic. Methods: There were 24 male Wistar rats that were randomly divided into 3 groups with 8 rats in each. They were group A (normal diet), group B (high-fat-diet), group C (chronic stress+ high-fat-diet). Group A was fed with normal diet, while group B and C were fed with high-fat-diet, going on for 55 days. From the 35th day, group B and C received one time of daily chroni...

  7. Inhibition of Peripheral Nerve Scarring by Calcium Antagonists, Also Known as Calcium Channel Blockers.

    Science.gov (United States)

    Xue, Jin-Wei; Jiao, Jian-Bao; Liu, Xiao-Feng; Jiang, Yuan-Tao; Yang, Guang; Li, Chun-Yu; Yin, Wei-Tian; Ling, Li

    2016-05-01

    The aim of this research was to investigate the impact of calcium channel blockers (verapamil) on the formation of scars in the sciatic nerve anastomosis after peripheral nerve injury. One hundred twenty healthy, male Sprague-Dawley rats were selected and prepared with right sciatic nerve injury for this study. Samples were selected at the fourth and 12th weeks, respectively, after treatment and observations were made on the nerve anastomosis healing and diameter. Image analysis and statistical processing were carried out relating to the results of the study. The diameter of the anastomosis of the treatment group at weeks 4 and 12 was noticeably smaller than the control group (P regeneration. It can effectively inhibit the formation of scarring from nerve injury. It also provided an excellent microenvironment for the regeneration of nerve fibers. PMID:26488333

  8. Arctium lappa ameliorates endothelial dysfunction in rats fed with high fat/cholesterol diets

    Directory of Open Access Journals (Sweden)

    Lee Yun

    2012-08-01

    Full Text Available Abstract Background Arctium lappa L. (Asteraceae, burdock, is a medicinal plant that is popularly used for treating hypertension, gout, hepatitis, and other inflammatory disorders. This study was performed to test the effect of ethanol extract of Arctium lappa L. (EAL seeds on vascular reactivity and inflammatory factors in rats fed a high fat/cholesterol diet (HFCD. Method EAL-I (100 mg·kg−1/day, EAL-II (200 mg·kg−1/day, and fluvastatin (3 mg·kg−1/day groups initially received HFCD alone for 8 weeks, with EAL supplementation provided during the final 6 weeks. Results Treatment with low or high doses of EAL markedly attenuated plasma levels of triglycerides and augmented plasma levels of high-density lipoprotein (HDL in HFCD-fed rats. Chronic treatment with EAL markedly reduced impairments of acetylcholine (ACh-induced relaxation of aortic rings. Furthermore, chronic treatment with EAL significantly lowered systolic blood pressure (SBP and maintained smooth and flexible intimal endothelial layers in HFCD-fed rats. Chronic treatment with EAL suppressed upregulation of intercellular adhesion molecule (ICAM-1, vascular cell adhesion molecule (VCAM-1, and E-selectin in the aorta. Chronic treatment with EAL also suppressed increases in matrix metalloproteinase (MMP-2 expression. These results suggested that EAL can inhibit HFCD-induced vascular inflammation in the rat model. Conclusion The present study provides evidence that EAL ameliorates HFCD-induced vascular dysfunction through protection of vascular relaxation and suppression of vascular inflammation.

  9. Leucine supplementation improves leptin sensitivity in high-fat diet fed rats

    Directory of Open Access Journals (Sweden)

    Xue-Wei Yuan

    2015-06-01

    Full Text Available Background: Several studies have reported the favorable effect of leucine supplementation on insulin resistance or insulin sensitivity. However, whether or not leucine supplementation improves leptin sensitivity remains unclear. Design: Forty-eight male Sprague-Dawley rats were fed with either a high-fat diet (HFD or HFD supplemented with 1.5, 3.0, and 4.5% leucine for 16 weeks. At the end of the experiment, serum leptin level was measured by ELISA, and leptin receptor (ObR in the hypothalamus was examined by immunohistochemistry. The protein expressions of ObR and leptin-signaling pathway in adipose tissues were detected by western blot. Results: No significant differences in body weight and food/energy intake existed among the four groups. Serum leptin levels were significantly lower, and ObR expression in the hypothalamus and adipose tissues was significantly higher in the three leucine groups than in the control group. These phenomena suggested that leptin sensitivity was improved in the leucine groups. Furthermore, the expressions of JAK2 and STAT3 (activated by ObR were significantly higher, and that of SOCS3 (inhibits leptin signaling was significantly lower in the three leucine groups than in the control group. Conclusions: Leucine supplementation improves leptin sensitivity in rats on HFD likely by promoting leptin signaling.

  10. Preventing High Fat Diet-induced Obesity and Improving Insulin Sensitivity through Neuregulin 4 Gene Transfer.

    Science.gov (United States)

    Ma, Yongjie; Gao, Mingming; Liu, Dexi

    2016-01-01

    Neuregulin 4 (NRG4), an epidermal growth factor-like signaling molecule, plays an important role in cell-to-cell communication during tissue development. Its function to regulate energy metabolism has recently been reported. This current study was designed to assess the preventive and therapeutic effects of NRG4 overexpression on high fat diet (HFD)-induced obesity. Using the hydrodynamic gene transfer method, we demonstrate that Nrg4 gene transfer in mice suppressed the development of diet-induced obesity, but did not affect pre-existing adiposity and body weight in obese mice. Nrg4 gene transfer curbed HFD-induced hepatic steatosis by inhibiting lipogenesis and PPARγ-mediated lipid storage. Concurrently, overexpression of NRG4 reduced chronic inflammation in both preventive and treatment studies, evidenced by lower mRNA levels of macrophage marker genes including F4/80, Cd68, Cd11b, Cd11c, and macrophage chemokine Mcp1, resulting in improved insulin sensitivity. Collectively, these results demonstrate that overexpression of the Nrg4 gene by hydrodynamic gene delivery prevents HFD-induced weight gain and fatty liver, alleviates obesity-induced chronic inflammation and insulin resistance, and supports the health benefits of NRG4 in managing obesity and obesity-associated metabolic disorders. PMID:27184920

  11. Effects of herbal mixture extracts on obesity in rats fed a high-fat diet

    Directory of Open Access Journals (Sweden)

    Mei-Yin Chien

    2016-07-01

    Full Text Available The aim of this study was to investigate and compare the effects of three herbal mixture extracts on obesity induced by high-fat diet (HFD in rats. The prescriptions—Pericarpium citri reticulatae and Fructus crataegi—were used as matrix components and mixed with Ampelopsis grossedentata, Salvia miltiorrhiza, and epigallocatechin-3-gallate (EGCG to form T1, T2, and T3 complexes, respectively. Results revealed that HFD feeding significantly increased body weight gain, fat deposition, plasma lipid profiles, hepatic lipid accumulation, and hepatic vacuoles formation, but decreased plasma levels of adiponectin in rats. Only the T1 complex showed the tendency, although not significantly so, for decreased HFD-induced body weight gain. T1 and T3 complexes significantly reduced HFD-induced fat deposition, and plasma levels of triglyceride, total cholesterol, and low-density lipoprotein cholesterol. Only the T1 complex significantly increased HFD-reduced adiponectin levels in plasma, but decreased HFD-increased triglyceride content in liver tissues. All complexes effectively inhibited HFD-induced vacuoles formation. The content of dihydromyricetin, salvianolic acid B, and EGCG in T1, T2, and T3 complexes was 18.25 ± 0.07%, 22.20 ± 0.10%, and 18.86 ± 0.04%, respectively. In summary, we demonstrated that herbal mixture extracts, especially T1 complex, exhibit antiobesity activity in HFD-fed rats.

  12. Effect of Lactobacillus plantarum Strain K21 on High-Fat Diet-Fed Obese Mice

    Directory of Open Access Journals (Sweden)

    Chien-Chen Wu

    2015-01-01

    Full Text Available Recent studies have demonstrated beneficial effects of specific probiotics on alleviating obesity-related disorders. Here we aimed to identify probiotics with potential antiobesity activity among 88 lactic acid bacterial strains via in vitro screening assays, and a Lactobacillus plantarum strain K21 was found to harbor abilities required for hydrolyzing bile salt, reducing cholesterol, and inhibiting the accumulation of lipid in 3T3-L1 preadipocytes. Furthermore, effects of K21 on diet-induced obese (DIO mice were examined. Male C57Bl/6J mice received a normal diet, high-fat diet (HFD, or HFD with K21 administration (109 CFU in 0.2 mL PBS/day for eight weeks. Supplementation of K21, but not placebo, appeared to alleviate body weight gain and epididymal fat mass accumulation, reduce plasma leptin levels, decrease cholesterol and triglyceride levels, and mitigate liver damage in DIO mice. Moreover, the hepatic expression of peroxisome proliferator-activated receptor-γ (PPAR-γ related to adipogenesis was significantly downregulated in DIO mice by K21 intervention. We also found that K21 supplementation strengthens intestinal permeability and modulates the amount of Lactobacillus spp., Bifidobacterium spp., and Clostridium perfringens in the cecal contents of DIO mice. In conclusion, our results suggest that dietary intake of K21 protects against the onset of HFD-induced obesity through multiple mechanisms of action.

  13. Anti-Obese Effect of Glucosamine and Chitosan Oligosaccharide in High-Fat Diet-Induced Obese Rats

    Directory of Open Access Journals (Sweden)

    Lanlan Huang

    2015-04-01

    Full Text Available Objective: This study is to evaluate the anti-obese effects of glucosamine (GLC and chitosan oligosaccharide (COS on high-fat diet-induced obese rats. Methods: The rats were randomly divided into twelve groups: a normal diet group (NF, a high-fat diet group (HF, Orlistat group, GLC high-, middle-, and low-dose groups (GLC-H, GLC-M, GLC-L, COS1 (COS, number-average molecular weight ≤1000 high-, middle-, and low-dose groups (COS1-H, COS1-M, COS1-L, and COS2 (COS, number-average molecular weight ≤3000 high-, middle-, and low-dose groups (COS2-H, COS2-M, COS2-L. All groups received oral treatment by gavage once daily for a period of six weeks. Results: Rats fed with COS1 gained the least weight among all the groups (P < 0.01, and these rats lost more weight than those treated with Orlistat. In addition to the COS2-H and Orlistat groups, the serum total cholesterol (CHO and low-density lipoprotein cholesterol (LDL-C levels were significantly reduced in all treatment groups compared to the HF group (P < 0.01. The various doses of GLC, COS1 and COS2 reduced the expression levels of PPARγ and LXRα mRNA in the white adipose tissue. Conclusions: The results above demonstrated that GLC, COS1, and COS2 improved dyslipidemia and prevented body weight gains by inhibiting the adipocyte differentiation in obese rats induced by a high-fat diet. Thus, these agents may potentially be used to treat obesity.

  14. Platelet hyperaggregability in high-fat fed rats: A role for intraplatelet reactive-oxygen species production

    Directory of Open Access Journals (Sweden)

    Monteiro Priscila F

    2012-01-01

    Full Text Available Abstract Background Adiposity greatly increases the risk of atherothrombotic events, a pathological condition where a chronic state of oxidative stress is reported to play a major role. This study aimed to investigate the involvement of (NO-soluble guanylyl cyclase (sGC signaling pathway in the platelet dysfunction from high fat-fed (HFF rats. Methods Male Wistar rats were fed for 10 weeks with standard chow (SCD or high-fat diet (HFD. ADP (10 μM- and thrombin (100 mU/ml-induced washed platelet aggregation were evaluated. Measurement of intracellular levels of ROS levels was carried out using flow cytometry. Cyclic GMP levels were evaluated using ELISA kits. Results High-fat fed rats exhibited significant increases in body weight, epididymal fat, fasting glucose levels and glucose intolerance compared with SCD group. Platelet aggregation induced by ADP (n = 8 and thrombin from HFD rats (n = 8 were significantly greater (P n = 6. N-acetylcysteine (NAC; 1 mM and PEG-catalase (1000 U/ml fully prevented the increased ROS production and platelet hyperaggregability in HFD group. The NO donors sodium nitroprusside (SNP; 10 μM and SNAP (10 μM, as well as the NO-independent soluble guanylyl cyclase stimulator BAY 41-2272 (10 μM inhibited the platelet aggregation in HFD group with lower efficacy (P P n = 4. Conclusions Metabolic abnormalities as consequence of HFD cause platelet hyperaggregability involving enhanced intraplatelet ROS production and decreased NO bioavailability that appear to be accompanied by potential defects in the prosthetic haem group of soluble guanylyl cyclase.

  15. Bupivacaine inhibits large conductance, voltage- and Ca2+- activated K+ channels in human umbilical artery smooth muscle cells

    OpenAIRE

    Martín, Pedro; Enrique, Nicolás; Palomo, Ana R. Roldán; Rebolledo, Alejandro; Milesi, Veronica

    2012-01-01

    Bupivacaine is a local anesthetic compound belonging to the amino amide group. Its anesthetic effect is commonly related to its inhibitory effect on voltage-gated sodium channels. However, several studies have shown that this drug can also inhibit voltage-operated K+ channels by a different blocking mechanism. This could explain the observed contractile effects of bupivacaine on blood vessels. Up to now, there were no previous reports in the literature about bupivacaine effects on large condu...

  16. Effect of inhibition of tyrosine phosphatases on voltage-operated calcium channel currents in rabbit isolated ear artery cells

    OpenAIRE

    Wijetunge, S; Lymn, J S; Hughes, A.D.

    1998-01-01

    The effect of increasing cellular tyrosine phosphorylation by inhibiting endogenous tyrosine phosphatases was examined on voltage-operated calcium channel currents in vascular smooth muscle cells.In single ear artery smooth muscle cells of the rabbit, studied by the whole cell voltage clamp technique, intracellular application of the tyrosine phosphatase inhibitors, sodium orthovanadate (100 μM) and peroxyvanadate (100 μM orthovanadate+1 mM H2O2) increased voltage-operated calcium channel cur...

  17. Ranolazine inhibition of hERG potassium channels: Drug–pore interactions and reduced potency against inactivation mutants

    OpenAIRE

    Du, Chunyun; Zhang, Yihong; El Harchi, Aziza; Christopher E. Dempsey; Hancox, Jules C.

    2014-01-01

    The antianginal drug ranolazine, which combines inhibitory actions on rapid and sustained sodium currents with inhibition of the hERG/IKr potassium channel, shows promise as an antiarrhythmic agent. This study investigated the structural basis of hERG block by ranolazine, with lidocaine used as a low potency, structurally similar comparator. Recordings of hERG current (IhERG) were made from cell lines expressing wild-type (WT) or mutant hERG channels. Docking simulations were performed using ...

  18. Inhibition of the human two-pore domain potassium channel, TREK-1, by fluoxetine and its metabolite norfluoxetine

    OpenAIRE

    Kennard, Louise E; Chumbley, Justin R.; Ranatunga, Kishani M.; Armstrong, Stephanie J; Veale, Emma L.; Mathie, Alistair

    2005-01-01

    Block of the human two-pore domain potassium (2-PK) channel TREK-1 by fluoxetine (ProzacR) and its active metabolite, norfluoxetine, was investigated using whole-cell patch-clamp recording of currents through recombinant channels in tsA 201 cells.Fluoxetine produced a concentration-dependent inhibition of TREK-1 current that was reversible on wash. The IC50 for block was 19 μM. Block by fluoxetine was voltage-independent. Fluoxetine (100 μM) produced an 84% inhibition of TREK-1 currents, but ...

  19. Inhibition of nitrite-induced toxicity in channel catfish by calcium chloride and sodium chloride

    Science.gov (United States)

    Tommasso J.R., Wright, M. I.; Simco, B.A.; Davis, K.B.

    1980-01-01

    Environmental chloride has been shown to inhibit methemoglobin formation in fish, thereby offering a protective effect against nitrite toxicity. Channel catfish (Ictalurus punctatus) were simultaneously exposed to various environmental nitrite and chloride levels (as either CaCl2 or NaCl) in dechlorinated tap water (40 mg/L total hardness, 47 mg/L alkalinity, 4 mg/L chloride, pH = 6.9-7.1, and temperature 21-24°C). Methemoglobin levels in fish simultaneously exposed to 2.5 mg/L nitrite and up to 30 mg/L chloride as either CaCl2 or NaCl were similar but significantly lower than in unprotected fish. Exposure to 10 mg/L nitrite and 60 mg/L chloride resulted in methemoglobin levels similar to those of the controls; most unprotected fish died. Fish exposed to 10 mg/L nitrite had significantly lower methemoglobin levels when protected with 15.0 mg/L chloride as CaCl2 than with NaCl. Fish exposed to nitrite in the presence of 60 mg/L chloride (as either CaCl2 or NaCl) had similar 24-h LC50 values that were significantly elevated above those obtained in the absence of chloride. Calcium had little effect on tolerance to nitrite toxicity in channel catfish in contrast to its large effect reported in steelhead trout (Salmo gairdneri).

  20. 1,3-propanediol binds deep inside the channel to inhibit water permeation through aquaporins.

    Science.gov (United States)

    Yu, Lili; Rodriguez, Roberto A; Chen, L Laurie; Chen, Liao Y; Perry, George; McHardy, Stanton F; Yeh, Chih-Ko

    2016-02-01

    Aquaporins and aquaglyceroporins (AQPs) are membrane channel proteins responsible for transport of water and for transport of glycerol in addition to water across the cell membrane, respectively. They are expressed throughout the human body and also in other forms of life. Inhibitors of human AQPs have been sought for therapeutic treatment for various medical conditions including hypertension, refractory edema, neurotoxic brain edema, and so forth. Conducting all-atom molecular dynamics simulations, we computed the binding affinity of acetazolamide to human AQP4 that agrees closely with in vitro experiments. Using this validated computational method, we found that 1,3-propanediol (PDO) binds deep inside the AQP4 channel to inhibit that particular aquaporin efficaciously. Furthermore, we used the same method to compute the affinities of PDO binding to four other AQPs and one aquaglyceroporin whose atomic coordinates are available from the protein data bank (PDB). For bovine AQP1, human AQP2, AQP4, AQP5, and Plasmodium falciparum PfAQP whose structures were resolved with high resolution, we obtained definitive predictions on the PDO dissociation constant. For human AQP1 whose PDB coordinates are less accurate, we estimated the dissociation constant with a rather large error bar. Taking into account the fact that PDO is generally recognized as safe by the US FDA, we predict that PDO can be an effective diuretic which directly modulates water flow through the protein channels. It should be free from the serious side effects associated with other diuretics that change the hydro-homeostasis indirectly by altering the osmotic gradients. PMID:26481430

  1. STUDY OF THE ANTIHYPERLIPIDEMIC, ANTIOXIDATIVE AND ANTIATHEROGENIC ACTIVITY OF TRITICUM AESTIVUM LINN. IN RABBIT RECEIVING HIGH FAT DIET

    OpenAIRE

    Das Swarnamoni; Hakim Abdul; Mittal Ajay

    2012-01-01

    The aim was to study of the antihyperlipidemic, antioxidative and antiatherogenic activity of Triticum aestivum Linn. in rabbit receiving high fat diet. Twenty rabbits of either sex were taken and divided into four groups five in each as - Normal Control- received normal diet, Hyperlipidemic control- received high fat diet, Test drug group - received high fat diet plus ethanolic extract of Triticum aestivum 500 mg/Kg /day orally and Standard Drug group- received high fat diet plus Atorvastati...

  2. Sugary, High-Fat Western Diet Tied to Denser Breast Tissue

    Science.gov (United States)

    ... dairy products (whole milk, high-fat cheeses and ice cream), processed meats (bacon, ham and salami)and refined ... researchers collected medical information, family and personal health history and self-reported data about diet. They also ...

  3. Stimulation of beta-adrenoceptors inhibits calcium-dependent potassium-channels in mouse macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Rosati, C.; Hannaert, P.; Dausse, J.P.; Braquet, P.; Garay, R.

    1986-12-01

    K/sup +/ efflux in mouse macrophages exhibited a rate constant (k/sub k/) of 0.67 +/- 0.04 (h)/sup -1/. This was strongly stimulated by increasing concentrations of the Ca/sup 2 +/ ionophore A23187 up to a maximal value of 4.01 +/- 0.25 (h)/sup -1/ with an IC/sub 50/ of 7.6 +/- 1.9 ..mu..M. Similar results were obtained with the Ca/sup 2 +/ ionophore ionomycin. Binding experiments with /sup 3/H-dihydroalprenolol revealed a high density of beta-adrenergic receptors with apparent dissociation constant of 2.03 +/- 0.06 nM. Isoproterenol at a concentration of 10/sup -6/ -10/sup -5/ M induced a two- to threefold stimulation of endogenous levels of cyclic AMP (cAMP). A23187-stimulated K/sup +/ efflux was partially inhibited by (i) stimulation of adenylate cyclase with isoproterenol, forskolin or, PGE/sub 1/; (ii) exogenous cAMP; and (iii) inhibition of phosphodiesterase with MIX (1-methyl-3-isobutylxanthine). Maximal inhibition of K/sup +/ efflux was obtained by simultaneous addition of isoproterenol and MIX. In dose-response curves, the isoproterenol-sensitive K/sup +/ efflux was half-maximally inhibited (IC/sub 50/) with 2-5 x 10/sup -10/ M of isoproterenol concentration. Propranolol was able to completely block the effect of isoproterenol, with an IC/sub 50/ of about 1-2 x 10/sup -7/ M. Isoproterenol and MIX did not inhibit A23187-stimulated K/sup +/ efflux in an incubation medium where NaCl was replaced by sucrose (or choline), suggesting the involvement of an Na/sup +/:Ca/sup 2 +/ exchange mechanism. The results show that stimulation of beta-adrenoceptors in mouse macrophages counter balances the opening of K/sup +/ channels induced by the calcium ionophore A23187. This likely reflects a decrease in cytoslic free calcium content via a cAMP-mediated stimulation of Na/sup +/:Ca/sup 2 +/ exchange.

  4. Effect of ARB on Expression of CD68 and MCP-1 in Adipose Tissue of Rats on Long-term High Fat Diet

    Institute of Scientific and Technical Information of China (English)

    Caihong GUO; Li YUAN; Xiaoling LIU; Aimin DU; Yan HUANG; Lili ZHANG

    2008-01-01

    In adipose tissue of rats on long-term high fat diet, the inflammatory changes the roles of angiotensin receptor blocker (ARB) in pimelitis and insulin resistance (IR) were observed. IR rat model was established by feeding high calorie and high fat diet. The change in insulin sensitivity was detected by euglycemic-hyperinsulinemic clamp technique 8 weeks after intervention by valsartan. The expression levels of CD68 and MCP-1 mRNA and proteins in adipose tissue were examined by RT-PCR and immunohistochemistry respectively. The parameters of blood glucose, insulin and blood lipid were analyzed. The results showed that in high fat diet group intra-abdominal obesity developed, the content of visceral fat and the number of inflammatory cells in local adipose tissue were significantly increased (p<0.01), the levels of serum triglyceride, free fatty acids and fasting serum insulin were markedly increased, the insulin sensitivity was significantly lowered (p<0.01), and the expression of CD68 and MCP-1 was significantly increased as compared with control group (P<0.01). In ARB interventional group, the content of visceral fat, the number of inflammatory cells and the expression of CD68 and MCP-1 in local adipose tissue were significantly reduced (all P<0.01), but the insulin sensitivity was significantly enhanced (P<0.01) as compared with high fat diet group. There were pimelitis and IR in rats with obesity induced by long-term high calorie and high fat diet. The ARB can significantly inhibit the infiltration of macrophages and the expression of MCP-1 in adipose tissue, thereby attenuating the inflammation and improving IR in rats.

  5. Melatonin ameliorates vascular endothelial dysfunction, inflammation, and atherosclerosis by suppressing the TLR4/NF-κB system in high-fat-fed rabbits.

    Science.gov (United States)

    Hu, Ze-Ping; Fang, Xiao-Ling; Fang, Nan; Wang, Xiao-Bian; Qian, Hai-Yan; Cao, Zhong; Cheng, Yuan; Wang, Bang-Ning; Wang, Yuan

    2013-11-01

    Vascular endothelial dysfunction (VED) and inflammation contribute to the initiation and progression of atherosclerosis. Melatonin (MLT) normalizes lipid profile, improves endothelial function, and possesses anti-inflammatory properties. However, the precise mechanisms are still unclear. This study investigated whether MLT could ameliorate VED, inflammation, and atherosclerosis by suppressing the Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) system in high-fat-fed rabbits. Rabbits were randomly divided into three groups that received a standard diet (control group), high-cholesterol diet (atherosclerosis group), or high-cholesterol diet plus 10 mg/kg/day MLT (MLT group) for 12 wk. After treatment, high-fat diet significantly increased serum lipid and inflammatory markers in rabbits in atherosclerosis group compared with that in control group. In addition, high-fat diet also induced VED and typical atherosclerotic plaque formation and increased intima/media thickness ratio, which were significantly improved by MLT therapy as demonstrated in MLT group. Histological and immunoblot analysis further showed that high-fat diet enhanced the expressions of TLR4, myeloid differentiation primary response protein (MyD88), and NF-κB p65, but decreased inhibitor of NF-κB (IκB) expression. By contrast, MLT therapy decreased the expressions of TLR4, MyD88, and NF-κB p65 and increased IκB expression. This study has demonstrated that MLT ameliorates lipid metabolism, VED, and inflammation and inhibits the progression of atherosclerosis in high-fat-fed rabbits. Moreover, our study indicates for the first time that suppression of the TLR4/NF-κB system in local vasculature with atherosclerotic damage is important for the protective effects of MLT. PMID:24006943

  6. PTPRT Regulates High-Fat Diet-Induced Obesity and Insulin Resistance

    OpenAIRE

    Feng, Xiujing; Scott, Anthony; Wang, Yong; Wang, Lan; Zhao, Yiqing; Doerner, Stephanie; Satake, Masanobu; Croniger, Colleen M.; Wang, Zhenghe

    2014-01-01

    Obesity is a risk factor for many human diseases. However, the underlying molecular causes of obesity are not well understood. Here, we report that protein tyrosine phosphatase receptor T (PTPRT) knockout mice are resistant to high-fat diet-induced obesity. Those mice avoid many deleterious side effects of high-fat diet-induced obesity, displaying improved peripheral insulin sensitivity, lower blood glucose and insulin levels. Compared to wild type littermates, PTPRT knockout mice show reduce...

  7. High-fat diet did not change metabolic response to acute stress in rats

    OpenAIRE

    Farrokhi, Babak; Ghalami, Jamileh; Hedayati, Mehdi; Rostamkhani, Fatemeh; Zardooz, Homeira

    2011-01-01

    This study investigated the effects of high-fat diet on metabolic factors in the presence of acute foot-shock and psychological stresses in male Wistar rats. The animals were divided into high-fat (45 % cow intra-abdominal fat) and normal (standard pellets) diet groups; then, each group was allocated into stressed and control groups. Stress was induced by a communication box. Blood samples were collected by retro-orbital-puncture method under isoflurane anesthesia. Plasma levels of gluc...

  8. Islet Cell Response to High Fat Programming in Neonate, Weanling and Adolescent Wistar Rats

    OpenAIRE

    Cerf, Marlon E.; Johan Louw

    2014-01-01

    Context High fat programming, by exposure to a high saturated fat diet during fetal and/or lactational life induces metabolic derangements and alters islet cell architecture in neonate and weanling rats. Objective The present study assessed metabolic hanges and islet cell dynamics in response to high fat maintenance during specific developmental periods in adolescent rats, with some parameters also studied in neonate and weanling rats. Methods The experimental groups comprised neonates, weanl...

  9. Beneficial effects of noni (Morinda citrifolia L.) juice on livers of high-fat dietary hamsters.

    Science.gov (United States)

    Lin, Yi-Ling; Chang, Yuan-Yen; Yang, Deng-Jye; Tzang, Bor-Show; Chen, Yi-Chen

    2013-09-01

    Polyphenols in noni juice (NJ) are mainly composed of phenolic acids, mainly gentisic, p-hydroxybenoic, and chlorogenic acids. To investigate the beneficial effects of NJ on the liver, hamsters were fed with two diets, normal-fat and high-fat diets. Furthermore, high-fat dietary hamsters were received distilled water, and 3, 6, and 9 mL NJ/kg BW, respectively. After a 6-week feeding period, the increased (p<0.05) sizes of liver and visceral fat in high-fat dietary hamsters compared to the control hamsters were ameliorated (p<0.05) by NJ supplementation. NJ also decreased (p<0.05) serum/liver lipids but enhanced (p<0.05) daily faecal lipid/bile acid outputs in the high-fat dietary hamsters. High-fat dietary hamsters supplemented with NJ had higher (p<0.05) liver antioxidant capacities but lowered (p<0.05) liver iNOS, COX-2, TNF-α, and IL-1β expressions, gelatinolytic levels of MMP9, and serum ALT values compared to those without NJ. Hence, NJ protects liver against a high-fat dietary habit via regulations of antioxidative and anti-inflammatory responses. PMID:23578611

  10. Hypothyroidism Exacerbates Thrombophilia in Female Rats Fed with a High Fat Diet

    Directory of Open Access Journals (Sweden)

    Harald Mangge

    2015-07-01

    Full Text Available Clotting abnormalities are discussed both in the context with thyroid dysfunctions and obesity caused by a high fat diet. This study aimed to investigate the impact of hypo-, or hyperthyroidism on the endogenous thrombin potential (ETP, a master indicator of clotting activation, on Sprague Dawley rats fed a normal or high fat diet. Female Sprague Dawley rats (n = 66 were grouped into normal diet (ND; n = 30 and high-fat diet (HFD; n = 36 groups and subdivided into controls, hypothyroid and hyperthyroid groups, induced through propylthiouracil or triiodothyronine (T3 treatment, respectively. After 12 weeks of treatment ETP, body weight and food intake were analyzed. Successfully induced thyroid dysfunction was shown by T3 levels, both under normal and high fat diet. Thyroid dysfunction was accompanied by changes in calorie intake and body weight. In detail, compared to euthyroid controls, hypothyroid rats showed significantly increased—and hyperthyroid animals significantly decreased—ETP levels. High fat diet potentiated these effects in both directions. In summary, we are the first to show that hypothyroidism and high fat diet potentiate the thrombotic capacity of the clotting system in Sprague Dawley rats. This effect may be relevant for cardiovascular disease where thyroid function is poorly understood as a pathological contributor in the context of clotting activity and obesogenic nutrition.

  11. The calmodulin inhibitor CGS 9343B inhibits voltage-dependent K+ channels in rabbit coronary arterial smooth muscle cells

    International Nuclear Information System (INIS)

    We investigated the effects of the calmodulin inhibitor CGS 9343B on voltage-dependent K+ (Kv) channels using whole-cell patch clamp technique in freshly isolated rabbit coronary arterial smooth muscle cells. CGS 9343B inhibited Kv currents in a concentration-dependent manner, with a half-maximal inhibitory concentration (IC50) value of 0.81 μM. The decay rate of Kv channel inactivation was accelerated by CGS 9343B. The rate constants of association and dissociation for CGS 9343B were 2.77 ± 0.04 μM−1 s−1 and 2.55 ± 1.50 s−1, respectively. CGS 9343B did not affect the steady-state activation curve, but shifted the inactivation curve toward to a more negative potential. Train pulses (1 or 2 Hz) application progressively increased the CGS 9343B-induced Kv channel inhibition. In addition, the inactivation recovery time constant was increased in the presence of CGS 9343B, suggesting that CGS 9343B-induced inhibition of Kv channel was use-dependent. Another calmodulin inhibitor, W-13, did not affect Kv currents, and did not change the inhibitory effect of CGS 9343B on Kv current. Our results demonstrated that CGS 9343B inhibited Kv currents in a state-, time-, and use-dependent manner, independent of calmodulin inhibition. - Highlights: • We investigated the effects of CGS 9394B on Kv channels. • CGS 9394B inhibited Kv current in a state-, time-, and use-dependent manner. • Caution is required when using CGS 9394B in vascular function studies

  12. Chemical chaperones reduce ER stress and adipose tissue inflammation in high fat diet-induced mouse model of obesity.

    Science.gov (United States)

    Chen, Yaqin; Wu, Zhihong; Zhao, Shuiping; Xiang, Rong

    2016-01-01

    Obesity, which is characteristic by chronic inflammation, is defined as abnormal or excessive fat accumulation in adipose tissues. Endoplasmic reticulum (ER) stress is increased in adipose tissue of obese state and is known to be strongly associated with chronic inflammation. The aim of this study was to investigate the effect of ER stress on adipokine secretion in obese mice and explore the potential mechanisms. In this study, we found high-fat diet induced-obesity contributed to strengthened ER stress and triggered chronic inflammation in adipose tissue. Chemical chaperones, 4-PBA and TUDCA, modified metabolic disorders and decreased the levels of inflammatory cytokines in obese mice fed a high-fat diet. The alleviation of ER stress is in accordance with the decrease of free cholesterol in adipose tissue. Furthermore chemical chaperones suppress NF-κB activity in adipose tissue of obese mice in vivo. In vitro studies showed IKK/NF-κB may be involved in the signal transduction of adipokine secretion dysfunction induced by ER stress. The present study revealed the possibility that inhibition of ER stress may be a novel drug target for metabolic abnormalities associated with obesity. Further studies are now needed to characterize the initial incentive of sustained ER stress in obese. PMID:27271106

  13. Antidiabetic Effects of Carassius auratus Complex Formula in High Fat Diet Combined Streptozotocin-Induced Diabetic Mice

    Directory of Open Access Journals (Sweden)

    Zhi-Hong Wang

    2014-01-01

    Full Text Available Carassius auratus complex formula, including Carassius auratus, Rhizoma dioscoreae, Lycium chinense, and Rehmannia glutinosa Libosch, is a combination prescription of traditional Chinese medicine, which has always been used to treat diabetes mellitus in ancient China. In this study, we provided experimental evidence for the use of Carassius auratus complex formula in the treatment of high fat diet combined streptozotocin- (STZ- induced type 2 diabetes. Carassius auratus complex formula aqueous extract was prepared and the effects of it on blood glucose, serum insulin, adipose tissue weight, oral glucose tolerance test (OGTT, total cholesterol, and triglyceride (TG levels in mice were measured. Moreover, adiponectin, TG synthesis related gene expressions, and the inhibitory effect of aldose reductase (AR were performed to evaluate its antidiabetic effects. After the 8-week treatment, blood glucose, insulin levels, and adipose tissue weight were significantly decreased. OGTT and HOMA-IR index showed improved glucose tolerance. It could also lower plasma TG, TC, and liver TG levels. Furthermore, Carassius auratus complex formula could inhibit the activity of AR and restore adiponectin expression in serum. Based on these findings, it is suggested that Carassius auratus complex formula possesses potent anti-diabetic effects on high fat diet combined STZ-induced diabetic mice.

  14. Enhanced Amelioration of High-Fat Diet-Induced Fatty Liver by Docosahexaenoic Acid and Lysine Supplementations

    Directory of Open Access Journals (Sweden)

    Hsin-Yu Lin

    2014-01-01

    Full Text Available Fatty liver disease is the most common pathological condition in the liver. Here, we generated high-fat diet-(HFD- induced nonalcoholic fatty liver disease (NAFLD in mice and tested the effects of docosahexaenoic acid (DHA and lysine during a four-week regular chow (RCfeeding. Our results showed that 1% lysine and the combination of 1% lysine + 1% DHA reduced body weight. Moreover, serum triglyceride levels were reduced by 1% DHA and 1% lysine, whereas serum alanine transaminase activity was reduced by 1% DHA and 1% DHA + 0.5% lysine. Switching to RC reduced hepatic lipid droplet accumulation, which was further reduced by the addition of DHA or lysine. Furthermore, the mRNA expressions of hepatic proinflammatory cytokines were suppressed by DHA and combinations of DHA + lysine, whereas the mRNA for the lipogenic gene, acetyl-CoA carboxylase 1 (ACC1, was suppressed by DHA. In the gonadal adipose tissues, combinations of DHA and lysine inhibited mRNA expression of lipid metabolism-associated genes, including ACC1, fatty acid synthase, lipoprotein lipase, and perilipin. In conclusion, the present study demonstrated that, in conjunction with RC-induced benefits, supplementation with DHA or lysine further ameliorated the high-fat diet-induced NAFLD and provided an alternative strategy to treat, and potentially prevent, NAFLD.

  15. TRESK background K(+ channel is inhibited by PAR-1/MARK microtubule affinity-regulating kinases in Xenopus oocytes.

    Directory of Open Access Journals (Sweden)

    Gabriella Braun

    Full Text Available TRESK (TWIK-related spinal cord K(+ channel, KCNK18 is a major background K(+ channel of sensory neurons. Dominant-negative mutation of TRESK is linked to familial migraine. This important two-pore domain K(+ channel is uniquely activated by calcineurin. The calcium/calmodulin-dependent protein phosphatase directly binds to the channel and activates TRESK current several-fold in Xenopus oocytes and HEK293 cells. We have recently shown that the kinase, which is responsible for the basal inhibition of the K(+ current, is sensitive to the adaptor protein 14-3-3. Therefore we have examined the effect of the 14-3-3-inhibited PAR-1/MARK, microtubule-associated-protein/microtubule affinity-regulating kinase on TRESK in the Xenopus oocyte expression system. MARK1, MARK2 and MARK3 accelerated the return of TRESK current to the resting state after the calcium-dependent activation. Several other serine-threonine kinase types, generally involved in the modulation of other ion channels, failed to influence TRESK current recovery. MARK2 phosphorylated the primary determinant of regulation, the cluster of three adjacent serine residues (S274, 276 and 279 in the intracellular loop of mouse TRESK. In contrast, serine 264, the 14-3-3-binding site of TRESK, was not phosphorylated by the kinase. Thus MARK2 selectively inhibits TRESK activity via the S274/276/279 cluster, but does not affect the direct recruitment of 14-3-3 to the channel. TRESK is the first example of an ion channel phosphorylated by the dynamically membrane-localized MARK kinases, also known as general determinants of cellular polarity. These results raise the possibility that microtubule dynamics is coupled to the regulation of excitability in the neurons, which express TRESK background potassium channel.

  16. Drug-induced Inhibition and Trafficking Disruption of ion Channels: Pathogenesis of QT Abnormalities and Drug-induced Fatal Arrhythmias.

    Science.gov (United States)

    Cubeddu, Luigi X

    2016-01-01

    Risk of severe and fatal ventricular arrhythmias, presenting as Torsade de Pointes (TdP), is increased in congenital and acquired forms of long QT syndromes (LQTS). Drug-induced inhibition of K+ currents, IKs, IKr, IK1, and/or Ito, delay repolarization, prolong QT, and increase the risk of TdP. Drug-induced interference with IKr is the most common cause of acquired LQTS/TdP. Multiple drugs bind to KNCH2-hERG-K+ channels affecting IKr, including antiarrythmics, antibiotics, antivirals, azole-antifungals, antimalarials, anticancer, antiemetics, prokinetics, antipsychotics, and antidepressants. Azithromycin has been recently added to this list. In addition to direct channel inhibition, some drugs interfere with the traffic of channels from the endoplasmic reticulum to the cell membrane, decreasing mature channel membrane density; e.g., pentamidine, geldalamicin, arsenic trioxide, digoxin, and probucol. Other drugs, such as ketoconazole, fluoxetine, norfluoxetine, citalopram, escitalopram, donepezil, tamoxifen, endoxifen, atazanavir, and roxitromycin, induce both direct channel inhibition and impaired channel trafficking. Although many drugs prolong the QT interval, TdP is a rare event. The following conditions increase the risk of drug-induced TdP: a) Disease states/electrolyte levels (heart failure, structural cardiac disease, bradycardia, hypokalemia); b) Pharmacogenomic variables (presence of congenital LQTS, subclinical ion-channel mutations, history of or having a relative with history of drug-induced long QT/TdP); c) Pharmacodynamic and kinetic factors (high doses, women, elderly, metabolism inhibitors, combining two or more QT prolonging drugs, drugs that prolong the QT and increase QT dispersion, and drugs with multiple actions on ion channels). Because most of these conditions are preventable, careful evaluation of risk factors and increased knowledge of drug use associated with repolarization abnormalities are strongly recommended. PMID:26926294

  17. Molecular mechanism of sulphonylurea block of K(ATP) channels carrying mutations that impair ATP inhibition and cause neonatal diabetes.

    Science.gov (United States)

    Proks, Peter; de Wet, Heidi; Ashcroft, Frances M

    2013-11-01

    Sulphonylurea drugs are the therapy of choice for treating neonatal diabetes (ND) caused by mutations in the ATP-sensitive K(+) channel (KATP channel). We investigated the interactions between MgATP, MgADP, and the sulphonylurea gliclazide with KATP channels expressed in Xenopus oocytes. In the absence of MgATP, gliclazide block was similar for wild-type channels and those carrying the Kir6.2 ND mutations R210C, G334D, I296L, and V59M. Gliclazide abolished the stimulatory effect of MgATP on all channels. Conversely, high MgATP concentrations reduced the gliclazide concentration, producing a half-maximal block of G334D and R201C channels and suggesting a mutual antagonism between nucleotide and gliclazide binding. The maximal extent of high-affinity gliclazide block of wild-type channels was increased by MgATP, but this effect was smaller for ND channels; channels that were least sensitive to ATP inhibition showed the smallest increase in sulphonylurea block. Consequently, G334D and I296L channels were not fully blocked, even at physiological MgATP concentrations (1 mmol/L). Glibenclamide block was also reduced in β-cells expressing Kir6.2-V59M channels. These data help to explain why patients with some mutations (e.g., G334D, I296L) are insensitive to sulphonylurea therapy, why higher drug concentrations are needed to treat ND than type 2 diabetes, and why patients with severe ND mutations are less prone to drug-induced hypoglycemia. PMID:23835339

  18. A tale of switched functions: from cyclooxygenase inhibition to M-channel modulation in new diphenylamine derivatives.

    Directory of Open Access Journals (Sweden)

    Asher Peretz

    Full Text Available Cyclooxygenase (COX enzymes are molecular targets of nonsteroidal anti-inflammatory drugs (NSAIDs, the most used medication worldwide. However, the COX enzymes are not the sole molecular targets of NSAIDs. Recently, we showed that two NSAIDs, diclofenac and meclofenamate, also act as openers of Kv7.2/3 K(+ channels underlying the neuronal M-current. Here we designed new derivatives of diphenylamine carboxylate to dissociate the M-channel opener property from COX inhibition. The carboxylate moiety was derivatized into amides or esters and linked to various alkyl and ether chains. Powerful M-channel openers were generated, provided that the diphenylamine moiety and a terminal hydroxyl group are preserved. In transfected CHO cells, they activated recombinant Kv7.2/3 K(+ channels, causing a hyperpolarizing shift of current activation as measured by whole-cell patch-clamp recording. In sensory dorsal root ganglion and hippocampal neurons, the openers hyperpolarized the membrane potential and robustly depressed evoked spike discharges. They also decreased hippocampal glutamate and GABA release by reducing the frequency of spontaneous excitatory and inhibitory post-synaptic currents. In vivo, the openers exhibited anti-convulsant activity, as measured in mice by the maximal electroshock seizure model. Conversion of the carboxylate function into amide abolished COX inhibition but preserved M-channel modulation. Remarkably, the very same template let us generating potent M-channel blockers. Our results reveal a new and crucial determinant of NSAID-mediated COX inhibition. They also provide a structural framework for designing novel M-channel modulators, including openers and blockers.

  19. Indomethacin treatment prevents high fat diet-induced obesity and insulin resistance but not glucose intolerance in C57BL/6J Mice

    DEFF Research Database (Denmark)

    Fjære, Even; Aune, Ulrike Liisberg; Røen, Kristin;

    2014-01-01

    a high fat/high sucrose (HF/HS) diet or a regular diet supplemented or not with indomethacin (±INDO) for 7 weeks. Development of obesity, insulin resistance, and glucose intolerance was monitored, and the effect of indomethacin on glucose-stimulated insulin secretion (GSIS) was measured in vivo...... by treatment with indomethacin. We demonstrate that indomethacin did not inhibit GSIS per se, but activation of GPR40 in the presence of indomethacin inhibited glucose-dependent insulin secretion in MIN6 cells. We conclude that constitutive high hepatic glucose output combined with impaired GSIS in response...

  20. Antiobesity Effect of Codonopsis lanceolata in High-Calorie/High-Fat-Diet-Induced Obese Rats

    Directory of Open Access Journals (Sweden)

    Hye-Kyung Choi

    2013-01-01

    Full Text Available The antiobesity effects of Codonopsis lanceolata (CL were evaluated in a high-calorie/high-fat-diet (HFD- induced obesity rat model and 3T3-L1 cells. The Sprague-Dawley male rats were fed a normal diet (ND or a HFD for a period of 12 weeks. The rats were subdivided into groups: ND, ND + wild Codonopsis lanceolata (wCL (900 mg/kg/day, p.o., ND + cultivated Codonopsis lanceolata (cCL (900 mg/kg/day, p.o., HFD, HFD + wCL (100, 300, or 900 mg/kg/day, p.o., HFD + cCL (100, 300, or 900 mg/kg/day, p.o., and HFD + sibutramine. The body weight gains of the administered HFD + CL (wCL or CCL were lower than those of the rats fed with only the HFD group. Moreover, the weight of adipose pads and the serum levels of triglycerides, total cholesterol, and low density lipoprotein cholesterol in the group administered HDL + CL were significantly lower than in the HFD group. The inhibitory effect of lipid accumulation in 3T3-L1 cells was measured by Oil Red O staining and reverse transcription-polymerase chain reaction (RT-PCR. Treatment of 3T3-L1 cells with wCL inhibited lipid accumulation and expression of C/EBPα and PPARγ. These results suggest that CL has a great potential as a functional food with anti-obesity effects and as a therapeutic alternative in the treatment of obesity.

  1. Anti-obesity and cardioprotective effects of cinnamic acid in high fat diet- induced obese rats.

    Science.gov (United States)

    Mnafgui, Kais; Derbali, Amal; Sayadi, Sami; Gharsallah, Neji; Elfeki, Abdelfattah; Allouche, Noureddine

    2015-07-01

    Obesity is a chronic metabolic disorder that is associated with numerous diseases including hyperlipidemia, diabetes mellitus, hypertension, atherosclerosis, cardiovascular disease, and cancer. Cinnamic acid is a phytochemical compound having many biological effects and could be considered for the management of obesity. This study is aimed to assess the possible anti-obesity and cardioprotective properties of cinnamic acid (CA) in high fat diet-fed rats (HFD). Male Wistar rats were divided into 4 groups. They received normal diet, HFD diet, HFD supplemented with fluvastatin (2 mg/kg/day) or cinnamic acid (30 mg/kg/day) for 7 weeks. The results showed an increase in body weight of HFD rats by ~27 % as compared to control group. Moreover, serum lipase activity underwent a significant rise by 103 % which led to an increase in the levels of total cholesterol (T-Ch), triglycerides (TG), LDL-cholesterol in serum of untreated HFD-fed rats. Furthermore, the concentration of leptin and angiotensin-converting enzyme (ACE) activity exhibited remarkable increases in serum of HFD-fed rats as compared to controls. Whereas, the administration of CA to HFD-fed rats improved the body weight gain and serum lipid profile and reverted back near to normal the activities of lipase and ACE. In addition, the echocardiography evidenced that CA is able to protect the aorta and aortic arch and avoided vasoconstriction by increasing their diameters and improved liver steatosis and kidney indices of toxicity. Overall, these results suggest that cinnamic acid exerts anti-obesity and antihypertensive effects through inhibition of lipid digestive enzymes and ACE. PMID:26139902

  2. Impact of high-fat diet on the proteome of mouse liver.

    Science.gov (United States)

    Benard, Outhiriaradjou; Lim, Jihyeon; Apontes, Pasha; Jing, Xiaohong; Angeletti, Ruth H; Chi, Yuling

    2016-05-01

    Chronic overnutrition, for instance, high-fat diet (HFD) feeding, is a major cause of rapidly growing incidence of metabolic syndromes. However, the mechanisms underlying HFD-induced adverse effects on human health are not clearly understood. HFD-fed C57BL6/J mouse has been a popular model employed to investigate the mechanisms. Yet, there is no systematic and comprehensive study of the impact of HFD on the protein profiles of the animal. Here, we present a proteome-wide study of the consequences of long-term HFD feeding. Utilizing a powerful technology, stable isotope labeling of mammals, we detected and quantitatively compared 965 proteins extracted from livers of chow-diet-fed and HFD-fed mice. Among which, 122 proteins were significantly modulated by HFD. Fifty-four percent of those 122 proteins are involved in metabolic processes and the majority participate in lipid metabolism. HFD up-regulates proteins that play important roles in fatty acid uptake and subsequent oxidation and are linked to the transcription factors PPARα and PGC-1α. HFD suppresses lipid biosynthesis-related proteins that play major roles in de novo lipogenesis and are linked to SREBP-1 and PPARγ. These data suggest that HFD-fed mice tend to develop enhanced fat utilization and suppressed lipid biosynthesis, understandably a self-protective mechanism to counteract to excessive fat loading, which causes liver steatosis. Enhanced fatty acid oxidation increases reactive oxygen species and inhibits glucose oxidation, which are associated with hyperglycemia and insulin resistance. This proteomics study provides molecular understanding of HFD-induced pathology and identifies potential targets for development of therapeutics for metabolic syndromes. PMID:27133419

  3. TNF-α upregulates sclerostin expression in obese mice fed a high-fat diet.

    Science.gov (United States)

    Baek, Kyunghwa; Hwang, Hyo Rin; Park, Hyun-Jung; Kwon, Arang; Qadir, Abdul S; Ko, Seong-Hee; Woo, Kyung Mi; Ryoo, Hyun-Mo; Kim, Gwan-Shik; Baek, Jeong-Hwa

    2014-05-01

    Sclerostin decreases bone mass by antagonizing the Wnt signaling pathway. We examined whether obesity-induced bone loss is associated with the expression of sclerostin. Five-week-old male mice were assigned to one of two groups (n = 10 each) and fed either a control diet (10% kcal from fat; CON) or a high-fat diet (60% kcal from fat; HF) for 12 weeks. Thex final body weight and whole body fat mass of the HF mice were higher than those of the CON mice. The distal femur cancellous bone mineral density and bone formation rate was lower in HF mice than in CON mice. The percent erosion surface was higher in the HF mice than the CON mice. The serum levels and femoral osteocytic protein expression levels of tumor necrosis factor-α (TNF-α) were significantly higher in HF mice than in CON mice. Sclerostin mRNA levels and osteocytic sclerostin protein levels in femoral cortex were also higher in HF mice than in CON mice. Sclerostin expression in MLO-Y4 osteocytes increased with TNF-α treatment, and TNF-α-induced sclerostin expression was blocked by the inhibition of NF-κB activation. Chromatin immunoprecipitation and a luciferase reporter assay demonstrated that NF-κB directly binds to the NF-κB binding elements on the mouse sost promoter and stimulates sclerostin expression. These results support a model in which, in the context of obesity or other inflammatory diseases that increase the production of TNF-α, TNF-α upregulates the expression of sclerostin through NF-κB signaling pathway, thus contributing to bone loss. PMID:24446199

  4. A high-fat diet impairs cooling-evoked brown adipose tissue activation via a vagal afferent mechanism.

    Science.gov (United States)

    Madden, Christopher J; Morrison, Shaun F

    2016-08-01

    In dramatic contrast to rats on a control diet, rats maintained on a high-fat diet (HFD) failed to activate brown adipose tissue (BAT) during cooling despite robust increases in their BAT activity following direct activation of their BAT sympathetic premotor neurons in the raphe pallidus. Cervical vagotomy or blockade of glutamate receptors in the nucleus of the tractus solitarii (NTS) reversed the HFD-induced inhibition of cold-evoked BAT activity. Thus, a HFD does not prevent rats from mounting a robust, centrally driven BAT thermogenesis; however, a HFD does alter a vagal afferent input to NTS neurons, thereby preventing the normal activation of BAT thermogenesis to cooling. These results, paralleling the absence of cooling-evoked glucose uptake in the BAT of obese humans, reveal a neural mechanism through which consumption of a HFD contributes to reduced energy expenditure and thus to weight gain. PMID:27354235

  5. Inhibition of the voltage-dependent chloride channel of Torpedo electric organ by diisopropylfluorophosphate and its reversal by oximes

    International Nuclear Information System (INIS)

    Diisopropylfluorophosphate (DFP), a potent organophosphate inhibitor of cholinesterases, was found to inhibit the specific binding of [35S]t-butylbicyclophosphorothionate (TBPS), specific chloride channels ligand, to the electric organ membranes of Torpedo, with a Ki of 21 +/- 3 μM. The binding sites of [35S]TBPS in the Torpedo membranes were found not to be GABA receptors or nicotinic acetylcholine receptors as previously described. Interestingly, a stimulation of the binding of [35S]TBPS was observed in the presence of atropine and three oximes, monopyridinium oxime 2-PAM, bispyridinium bis-oxime TMB-4 and H-oxime HI-6. The maximal stimulation was 300-500% of control, after which, the stimulation was reversed at higher concentrations. The three oximes protected by more than 95% the inhibition by 1 mM DFP of the binding of [35S]TBPS to the voltage-dependent chloride channel. However, atropine protected only 20% of the inhibited channel. These results, thus, suggest that the protection against the toxic effects of DFP or other anticholinesterase agents by the tested oximes may not be solely a result of the reactivation of cholinesterases but also the protection of the voltage-dependent chloride channel

  6. Krill Oil Ameliorates Mitochondrial Dysfunctions in Rats Treated with High-Fat Diet.

    Science.gov (United States)

    Ferramosca, Alessandra; Conte, Annalea; Zara, Vincenzo

    2015-01-01

    In recent years, several studies focused their attention on the role of dietary fats in the pathogenesis of hepatic steatosis. It has been demonstrated that a high-fat diet is able to induce hyperglycemia, hyperinsulinemia, obesity, and nonalcoholic fatty liver disease. On the other hand, krill oil, a novel dietary supplement of n-3 PUFAs, has the ability to improve lipid and glucose metabolism, exerting possible protective effects against hepatic steatosis. In this study we have investigated the effects of krill oil on mitochondrial energetic metabolism in animals fed a high-fat diet. To this end, male Sprague-Dawley rats were divided into three groups and fed for 4 weeks with a standard diet (control group), a diet with 35% fat (HF group), or a high-fat diet supplemented with 2.5% krill oil (HF+KO group). The obtained results suggest that krill oil promotes the burning of fat excess introduced by the high-fat diet. This effect is obtained by stimulating mitochondrial metabolic pathways such as fatty acid oxidation, Krebs cycle, and respiratory chain complexes activity. Modulation of the expression of carrier proteins involved in mitochondrial uncoupling was also observed. Overall, krill oil counteracts the negative effects of a high-fat diet on mitochondrial energetic metabolism. PMID:26301251

  7. Krill Oil Ameliorates Mitochondrial Dysfunctions in Rats Treated with High-Fat Diet

    Directory of Open Access Journals (Sweden)

    Alessandra Ferramosca

    2015-01-01

    Full Text Available In recent years, several studies focused their attention on the role of dietary fats in the pathogenesis of hepatic steatosis. It has been demonstrated that a high-fat diet is able to induce hyperglycemia, hyperinsulinemia, obesity, and nonalcoholic fatty liver disease. On the other hand, krill oil, a novel dietary supplement of n-3 PUFAs, has the ability to improve lipid and glucose metabolism, exerting possible protective effects against hepatic steatosis. In this study we have investigated the effects of krill oil on mitochondrial energetic metabolism in animals fed a high-fat diet. To this end, male Sprague-Dawley rats were divided into three groups and fed for 4 weeks with a standard diet (control group, a diet with 35% fat (HF group, or a high-fat diet supplemented with 2.5% krill oil (HF+KO group. The obtained results suggest that krill oil promotes the burning of fat excess introduced by the high-fat diet. This effect is obtained by stimulating mitochondrial metabolic pathways such as fatty acid oxidation, Krebs cycle, and respiratory chain complexes activity. Modulation of the expression of carrier proteins involved in mitochondrial uncoupling was also observed. Overall, krill oil counteracts the negative effects of a high-fat diet on mitochondrial energetic metabolism.

  8. Exercise and a High Fat Diet Synergistically Increase the Pantothenic Acid Requirement in Rats.

    Science.gov (United States)

    Takahashi, Kei; Fukuwatari, Tsutomu; Shibata, Katsumi

    2015-01-01

    It is thought that both exercise and dietary composition increase the utilization of, and thus the requirement for, certain water-soluble vitamins. However, there have been no studies evaluating the combined impacts of exercise and dietary composition on vitamin utilization. In this experiment, rats were fed a pantothenic acid (PaA)-restricted (0.004 g PaA-Ca/kg diet) diet containing 5% (ordinary amount of dietary fat) or 20% fat (high fat), and were forced to swim until exhaustion every other day for 22 d. PaA status was assessed by urinary excretion, which reflects body stores of water-soluble vitamins. The urinary excretion of PaA in rats fed a 5% fat diet was not affected by swimming (5% fat + non-swimming vs. 5% fat + swim; p>0.05). Excretion of PaA was decreased by the high-fat diet (5% fat + non-swim vs. 20% fat + non-swim; pexercise (20% fat + non-swim vs. 20% fat + swim; pexercise and a high-fat diet. Plasma PaA concentrations showed changes similar to those seen for urinary excretion. The experiment was then repeated using rats fed a PaA-sufficient (0.016 g PaA-Ca/kg diet) diet, and PaA excretion was again synergistically decreased by the combination of exercise and a high-fat diet (pexercise and a high-fat diet synergistically increases the requirement for PaA. PMID:26226957

  9. A high-fat diet negatively affects rat sperm mitochondrial respiration.

    Science.gov (United States)

    Ferramosca, A; Conte, A; Moscatelli, N; Zara, V

    2016-05-01

    Recent evidences have linked abdominal obesity, insulin resistance, and dyslipidemia to male infertility. Since a defective energy metabolism may play an important role in the impairment of sperm quality, the aim of this study is to investigate the sperm energetic metabolism in rats fed with a high-fat diet, an animal model associated with metabolic syndrome development. Sexually mature male Sprague-Dawley rats were divided into two groups and fed for 4 weeks a standard diet (control group) or a diet enriched in 35% of fat (high fat group). Liver and adipose tissue weight, plasma glucose, insulin, and lipid concentrations were determined. Activities of enzymes involved in sperm energetic metabolism were evaluated by spectrophotometric assays. Sperm mitochondrial respiratory activity was evaluated with a polarographic assay of oxygen consumption. The administration of a high-fat diet caused a significant increase in body weight of rats and provoked hyperglycemia, hyperinsulinemia, and dyslipidemia. In these animals, we also observed a reduction in sperm concentration and motility. The investigation of sperm energetic metabolism in animals fed a high-fat diet revealed an impairment in the activity of pyruvate and lactate dehydrogenase, citrate synthase, and respiratory chain complexes. A parallel reduction in the cellular levels of adenosine triphosphate (ATP) and an increase in oxidative damage were also observed. A defective energy metabolism may play an important role in the impairment of sperm quality in the high-fat diet fed rats. PMID:27062222

  10. Role of high-fat diet in stress response of Drosophila.

    Directory of Open Access Journals (Sweden)

    Erilynn T Heinrichsen

    Full Text Available Obesity is associated with many diseases, one of the most common being obstructive sleep apnea (OSA, which in turn leads to blood gas disturbances, including intermittent hypoxia (IH. Obesity, OSA and IH are associated with metabolic changes, and while much mammalian work has been done, mechanisms underlying the response to IH, the role of obesity and the interaction of obesity and hypoxia remain unknown. As a model organism, Drosophila offers tremendous power to study a specific phenotype and, at a subsequent stage, to uncover and study fundamental mechanisms, given the conservation of molecular pathways. Herein, we characterize the phenotype of Drosophila on a high-fat diet in normoxia, IH and constant hypoxia (CH using triglyceride and glucose levels, response to stress and lifespan. We found that female flies on a high-fat diet show increased triglyceride levels (p<0.001 and a shortened lifespan in normoxia, IH and CH. Furthermore, flies on a high-fat diet in normoxia and CH show diminished tolerance to stress, with decreased survival after exposure to extreme cold or anoxia (p<0.001. Of interest, IH seems to rescue this decreased cold tolerance, as flies on a high-fat diet almost completely recovered from cold stress following IH. We conclude that the cross talk between hypoxia and a high-fat diet can be either deleterious or compensatory, depending on the nature of the hypoxic treatment.

  11. Upregulation of bile acid receptor TGR5 and nNOS in gastric myenteric plexus is responsible for delayed gastric emptying after chronic high-fat feeding in rats.

    Science.gov (United States)

    Zhou, Hui; Zhou, Shiyi; Gao, Jun; Zhang, Guanpo; Lu, Yuanxu; Owyang, Chung

    2015-05-15

    Chronic high-fat feeding is associated with functional dyspepsia and delayed gastric emptying. We hypothesize that high-fat feeding upregulates gastric neuronal nitric oxide synthase (nNOS) expression, resulting in delayed gastric emptying. We propose this is mediated by increased bile acid action on bile acid receptor 1 (TGR5) located on nNOS gastric neurons. To test this hypothesis, rats were fed regular chow or a high-fat diet for 2 wk. Rats fed the high-fat diet were subjected to concurrent feeding with oral cholestyramine or terminal ileum resection. TGR5 and nNOS expression in gastric tissue was measured by immunohistochemistry, PCR, and Western blot. Gastric motility was assessed by organ bath and solid-phase gastric emptying studies. The 2-wk high-fat diet caused a significant increase in neurons coexpressing nNOS and TGR5 in the gastric myenteric plexus and an increase in nNOS and TGR5 gene expression, 67 and 111%, respectively. Enhanced nonadrenergic, noncholinergic (NANC) relaxation, deoxycholic acid (DCA)-induced inhibition in fundic tissue, and a 26% delay in gastric emptying accompanied these changes. A 24-h incubation of whole-mount gastric fundus with DCA resulted in increased nNOS and TGR5 protein expression, 41 and 37%, respectively. Oral cholestyramine and terminal ileum resection restored the enhanced gastric relaxation, as well as the elevated nNOS and TGR5 expression evoked by high-fat feeding. Cholestyramine also prevented the delay in gastric emptying. We conclude that increased levels of circulatory bile acids induced by high-fat feeding upregulate nNOS and TGR5 expression in the gastric myenteric plexus, resulting in enhanced NANC relaxation and delayed gastric emptying. PMID:25540233

  12. Upregulation of bile acid receptor TGR5 and nNOS in gastric myenteric plexus is responsible for delayed gastric emptying after chronic high-fat feeding in rats

    Science.gov (United States)

    Zhou, Hui; Zhou, Shiyi; Gao, Jun; Zhang, Guanpo; Lu, Yuanxu

    2014-01-01

    Chronic high-fat feeding is associated with functional dyspepsia and delayed gastric emptying. We hypothesize that high-fat feeding upregulates gastric neuronal nitric oxide synthase (nNOS) expression, resulting in delayed gastric emptying. We propose this is mediated by increased bile acid action on bile acid receptor 1 (TGR5) located on nNOS gastric neurons. To test this hypothesis, rats were fed regular chow or a high-fat diet for 2 wk. Rats fed the high-fat diet were subjected to concurrent feeding with oral cholestyramine or terminal ileum resection. TGR5 and nNOS expression in gastric tissue was measured by immunohistochemistry, PCR, and Western blot. Gastric motility was assessed by organ bath and solid-phase gastric emptying studies. The 2-wk high-fat diet caused a significant increase in neurons coexpressing nNOS and TGR5 in the gastric myenteric plexus and an increase in nNOS and TGR5 gene expression, 67 and 111%, respectively. Enhanced nonadrenergic, noncholinergic (NANC) relaxation, deoxycholic acid (DCA)-induced inhibition in fundic tissue, and a 26% delay in gastric emptying accompanied these changes. A 24-h incubation of whole-mount gastric fundus with DCA resulted in increased nNOS and TGR5 protein expression, 41 and 37%, respectively. Oral cholestyramine and terminal ileum resection restored the enhanced gastric relaxation, as well as the elevated nNOS and TGR5 expression evoked by high-fat feeding. Cholestyramine also prevented the delay in gastric emptying. We conclude that increased levels of circulatory bile acids induced by high-fat feeding upregulate nNOS and TGR5 expression in the gastric myenteric plexus, resulting in enhanced NANC relaxation and delayed gastric emptying. PMID:25540233

  13. Solanum nigrum Protects against Hepatic Fibrosis via Suppression of Hyperglycemia in High-Fat/Ethanol Diet-Induced Rats

    Directory of Open Access Journals (Sweden)

    Cheng-Jeng Tai

    2016-02-01

    Full Text Available Background: Advanced glycation end products (AGEs signal through the receptor for AGE (RAGE, which can lead to hepatic fibrosis in hyperglycemia and hyperlipidemia. We investigated the inhibitory effect of aqueous extracts from Solanum nigrum (AESN on AGEs-induced RAGE signaling and activation of hepatic stellate cells (HSCs and hyperglycemia induced by high-fat diet with ethanol. Methods: An animal model was used to evaluate the anti-hepatic fibrosis activity of AESN in rats fed a high-fat diet (HFD; 30% with ethanol (10%. Male Wistar rats (4 weeks of age were randomly divided into four groups (n = 6: (1 control (basal diet; (2 HFD (30% + ethanol (10% (HFD/ethanol; (3 HFD/ethanol + AESN (100 mg/kg, oral administration; and (4 HFD/ethanol + pioglitazone (10 mg/kg, oral administration and treated with HFD for 6 months in the presence or absence of 10% ethanol in dietary water. Results: We found that AESN improved insulin resistance and hyperinsulinemia, and downregulated lipogenesis via regulation of the peroxisome proliferator-activated receptor α (PPARα, PPARγ co-activator (PGC-1α, carbohydrate response element-binding protein (ChREBP, acetyl-CoA carboxylase (ACC, and fatty acid synthase (FAS mRNA levels in the liver of HFD/ethanol-treated rats. In turn, AESN may delay and inhibit the progression of hepatic fibrosis, including α-smooth muscle actin (α-SMA inhibition and MMP-2 production. Conclusions: These results suggest that AESN may be further explored as a novel anti-fibrotic strategy for the prevention of liver disease.

  14. GABA/sub B/ receptor activation inhibits Ca2+-activated potassium channels in synaptosomes: involvement of G-proteins

    International Nuclear Information System (INIS)

    86Rb-efflux assay from preloaded synaptosomes of rat cerebral cortex was developed to study the effect of GABA/sub B/ receptor agonist baclofen on Ca2+-activated K+-channels. Depolarization of 86Rb-loaded synaptosomes in physiological buffer increased Ca2+-activated 86Rb-efflux by 400%. The 86Rb-efflux was blocked by quinine sulfate, tetraethylammonium, and La3+ indicating the involvement of Ca2+-activated K+-channels. (-)Baclofen inhibited Ca2+-activated 86Rb-efflux in a stereospecific manner. The inhibitory effect of (-)baclofen was mediated by GABA/sub B/ receptor activation, since it was blocked by GABA/sub B/ antagonist phaclofen, but not by bicuculline. Further, pertussis toxin also blocked the ability of baclofen or depolarizing action to affect Ca2+-activated K+-channels. These results suggest that baclofen inhibits Ca2+-activated K+-channels in synaptosomes and these channels are regulated by G-proteins. This assay may provide an ideal in vitro model to study GABA/sub B/ receptor pharmacology

  15. Extract of Kuding tea prevents high-fat diet-induced metabolic disorders in C57BL/6 mice via liver X receptor (LXR β antagonism.

    Directory of Open Access Journals (Sweden)

    Shengjie Fan

    Full Text Available OBJECTIVE: To investigate the effects of ilex kudingcha C. J. Tseng (kuding tea, a traditional beverage in China, on the metabolic disorders in C57BL/6 mice induced by high-fat diets. DESIGN: For the preventive experiment, the female C57BL/6 mice were fed with a standard diet (Chow, high-fat diet (HF, and high-fat diet mixed with 0.05% ethanol extract of kuding tea (EK for 5 weeks. For the therapeutic experiment, the C57BL/6 mice were fed high-fat diet for 3 months, and then mice were split and EK was given with oral gavages for 2 weeks at 50 mg/day/kg. Body weight and daily food intake amounts were measured. At the end of treatment, the adipocyte images were assayed with a scanning electron microscope, and the fasting blood glucose, glucose tolerance test, serum lipid profile and lipids in the livers were analyzed. A reporter gene assay system was used to test the whether EK could act on nuclear receptor transcription factors, and the gene expression analysis was performed with a quantitative PCR assay. RESULTS: In the preventive treatment, EK blocked the body weight gain, reduced the size of the adipocytes, lowered serum triglyceride, cholesterol, LDL-cholesterol, fasting blood glucose levels and glucose tolerance in high-fat diet-fed C57BL/6 mice. In the therapeutic treatment, EK reduced the size of the white adipocytes, serum TG and fasting blood glucose levels in obese mice. With the reporter assay, EK inhibited LXRβ transactivity and mRNA expression of LXRβ target genes. CONCLUSION: We observed that EK has both preventive and therapeutic roles in metabolic disorders in mice induced with high-fat diets. The effects appear to be mediated through the antagonism of LXRβ transactivity. Our data indicate that kuding tea is a useful dietary therapy and a potential source for the development of novel anti-obesity and lipid lowering drugs.

  16. Activation, Permeability, and Inhibition of Astrocytic and Neuronal Large Pore (Hemi)channels

    DEFF Research Database (Denmark)

    Hansen, Daniel Bloch; Ye, Zu-Cheng; Calloe, Kirstine;

    2014-01-01

    overlapping sensitivity to the inhibitors Brilliant Blue, gadolinium, and carbenoxolone. These results demonstrated isoform-specific characteristics among the large pore membrane channels; an open (hemi)channel is not a nonselective channel. With these isoform-specific properties in mind, we characterized the...

  17. High fat, low carbohydrate diet limit fear and aggression in Göttingen minipigs

    DEFF Research Database (Denmark)

    Haagensen, Annika Maria Juul; Sørensen, Dorte Bratbo; Sandøe, Peter;

    2014-01-01

    High fat, low carbohydrate diets have become popular, as short-term studies show that such diets are effective for reducing body weight, and lowering the risk of diabetes and cardiovascular disease. There is growing evidence from both humans and other animals that diet affects behaviour and intake...... of fat has been linked, positively and negatively, with traits such as exploration, social interaction, anxiety and fear. Animal models with high translational value can help provide relevant and important information in elucidating potential effects of high fat, low carbohydrate diets on human...... behaviour. Twenty four young, male Göttingen minipigs were fed either a high fat/cholesterol, low carbohydrate diet or a low fat, high carbohydrate/sucrose diet in contrast to a standard low fat, high carbohydrate minipig diet. Spontaneous behaviour was observed through video recordings of home pens and...

  18. Inhibition of voltage-gated potassium channels mediates uncarboxylated osteocalcin-regulated insulin secretion in rat pancreatic β cells.

    Science.gov (United States)

    Gao, Jingying; Zhong, Xiangqin; Ding, Yaqin; Bai, Tao; Wang, Hui; Wu, Hongbin; Liu, Yunfeng; Yang, Jing; Zhang, Yi

    2016-04-15

    Insulin secretion from pancreatic β cells is important to maintain glucose homeostasis and is regulated by electrical activities. Uncarboxylated osteocalcin, a bone-derived protein, has been reported to regulate glucose metabolism by increasing insulin secretion, stimulating β cell proliferation and improving insulin sensitivity. But the underlying mechanisms of uncarboxylated osteocalcin-modulated insulin secretion remain unclear. In the present study, we investigated the relationship of uncarboxylated osteocalcin-regulated insulin secretion and voltage-gated potassium (KV) channels, voltage-gated calcium channels in rat β cells. Insulin secretion was measured by radioimmunoassay. Channel currents and membrane action potentials were recorded using the conventional whole-cell patch-clamp technique. Calcium imaging system was used to analyze intracellular Ca(2+) concentration ([Ca(2+)]i). The data show that under 16.7mmol/l glucose conditions uncarboxylated osteocalcin alone increased insulin secretion and [Ca(2+)]i, but with no such effects on insulin secretion and [Ca(2+)]i in the presence of a KV channel blocker, tetraethylammonium chloride. In the patch-clamp experiments, uncarboxylated osteocalcin lengthened action potential duration and significantly inhibited KV currents, but had no influence on the characteristics of voltage-gated calcium channels. These results indicate that KV channels are involved in uncarboxylated osteocalcin-regulated insulin secretion in rat pancreatic β cells. By inhibiting KV channels, uncarboxylated osteocalcin prolongs action potential duration, increases intracellular Ca(2+) concentration and finally promotes insulin secretion. This finding provides new insight into the mechanisms of osteocalcin-modulated insulin secretion. PMID:26927753

  19. Presynaptic GABAB receptors reduce transmission at parabrachial synapses in the lateral central amygdala by inhibiting N-type calcium channels.

    Science.gov (United States)

    Delaney, A J; Crane, J W

    2016-01-01

    The nocioceptive information carried by neurons of the pontine parabrachial nucleus to neurons of the lateral division of the central amydala (CeA-L) is thought to contribute to the affective components of pain and is required for the formation of conditioned-fear memories. Importantly, excitatory transmission between parabrachial axon terminals and CeA-L neurons can be inhibited by a number of presynaptic receptors linked to Gi/o-type G-proteins, including α2-adrenoceptors and GABAB receptors. While the intracellular signalling pathway responsible for α2-adrenoceptor inhibition of synaptic transmission at this synapse is known, the mechanism by which GABAB receptors inhibits transmission has not been determined. The present study demonstrates that activation of presynaptic GABAB receptors reduces excitatory transmission between parabrachial axon terminals and CeA-L neurons by inhibiting N-type calcium channels. While the involvement of Gβγ subunits in mediating the inhibitory effects of GABAB receptors on N-type calcium channels is unclear, this inhibition does not involve Gβγ-independent activation of pp60C-src tyrosine kinase. The results of this study further enhance our understanding of the modulation of the excitatory input from parabrachial axon terminals to CeA-L neurons and indicate that presynaptic GABAB receptors at this synapse could be valuable therapeutic targets for the treatment of fear- and pain-related disorders. PMID:26755335

  20. Gynura procumbens Merr. decreases blood pressure in rats by vasodilatation via inhibition of calcium channels

    Directory of Open Access Journals (Sweden)

    See-Ziau Hoe

    2011-01-01

    Full Text Available INTRODUCTION: Gynura procumbens has been shown to decrease blood pressure via inhibition of the angiotensinconverting enzyme. However, other mechanisms that may contribute to the hypotensive effect have not been studied. OBJECTIVES: To investigate the cardiovascular effects of a butanolic fraction of Gynura procumbens in rats. METHODS: Anaesthetized rats were given intravenous bolus injections of butanolic fraction at doses of 2.5-20 mg/kg in vivo. The effect of butanolic fraction on vascular reactivity was recorded in isolated rat aortic rings in vitro. RESULTS: Intravenous administrations of butanolic fraction elicited significant (p<0.001 and dose-dependent decreases in the mean arterial pressure. However, a significant (p<0.05 decrease in the heart rate was observed only at the higher doses (10 and 20 mg/kg. In isolated preparations of rat aortic rings, phenylephrine (1×10-6 M- or potassium chloride (8×10-2 M-precontracted endothelium-intact and -denuded tissue; butanolic fraction (1×10-6-1×10-1 g/ml induced similar concentration-dependent relaxation of the vessels. In the presence of 2.5×10-3 and 5.0×10-3 g/ml butanolic fraction, the contractions induced by phenylephrine (1×10-9-3×10-5 M and potassium chloride (1×10-2-8×10-2 M were significantly antagonized. The calcium-induced vasocontractions (1×10-4-1×10-2 M were antagonized by butanolic fraction concentration-dependently in calcium-free and high potassium (6×10-2 M medium, as well as in calcium- and potassium-free medium containing 1×10-6 M phenylephrine. However, the contractions induced by noradrenaline (1×10-6 M and caffeine (4.5×10-2 M were not affected by butanolic fraction. CONCLUSION: Butanolic fraction contains putative hypotensive compounds that appear to inhibit calcium influx via receptor-operated and/or voltage-dependent calcium channels to cause vasodilation and a consequent fall in blood pressure.

  1. Atrial-selective prolongation of refractory period with AVE0118 is due principally to inhibition of sodium channel activity

    OpenAIRE

    Burashnikov, Alexander; Barajas-Martinez, Hector; Hu, Dan; Nof, Eyal; Blazek, Jonathan; Antzelevitch, Charles

    2012-01-01

    AVE0118’s action to prolong effective refractory period (ERP) in atria but not ventricles is thought to be due to its inhibition of IKur. However, in non-remodeled atria, AVE0118 prolongs ERP but not action potential duration (APD70-90), which can be explained with inhibition of sodium, but not potassium channel current. ERP, APD, and the maximum rate of rise of the AP upstroke (Vmax) were measured in canine isolated coronary-perfused right atrial and in superfused ventricular tissue preparat...

  2. Curcumin Inhibits Angiogenesis and Adipogenesis in Cell Culture System and in Mice Fed High Fat Diet

    Science.gov (United States)

    Angiogenesis is necessary for the growth of adipose tissue. Dietary polyphenols may suppress growth of adipose tissue through their antiangiogenic activity and by modulating adipocyte metabolism. In the present study, we examined the effect of curcumin on angiogenesis and adipocyte development in a ...

  3. Raspberry Ketone Protects Rats Fed High-Fat Diets Against Nonalcoholic Steatohepatitis

    OpenAIRE

    Wang, Lili; Meng, Xianjun; Zhang, Fengqing

    2012-01-01

    The protective effect of raspberry ketone against nonalcoholic steatohepatitis (NASH) was tested by using a high-fat diet-induced NASH model, and its mechanism was explored. Forty Sprague–Dawley rats with a 1:1 male to female ratio were randomly divided into five groups: the normal control (NC) group (n=8) fed normal diet for 8 weeks, the model control (MC) group (n=8) fed high-fat diet (82% standard diet, 8.3% yolk powder, 9.0% lard, 0.5% cholesterol, and 0.2% sodium taurocholate), and the r...

  4. Fructose-induced leptin resistance exacerbates weight gain in response to subsequent high-fat feeding

    OpenAIRE

    Shapiro, Alexandra; Mu, Wei; Roncal, Carlos; Cheng, Kit-Yan; Richard J Johnson; Scarpace, Philip J.

    2008-01-01

    It has been suggested that increased fructose intake is associated with obesity. We hypothesized that chronic fructose consumption causes leptin resistance, which subsequently may promote the development of obesity in response to a high-fat diet. Sprague-Dawley rats were fed a fructose-free control or 60% fructose diet for 6 mo and then tested for leptin resistance. Half of the rats in each group were then switched to high-fat diet for 2 wk, while the other half continued on their respective ...

  5. Whey Protein Reduces Early Life Weight Gain in Mice Fed a High-Fat Diet

    OpenAIRE

    Tranberg, Britt; Hellgren, Lars; Lykkesfeldt, Jens; Sejrsen, Kristen; Jeamet, Aymeric; Rune, Ida; Ellekilde, Merete; Nielsen, Dennis Sandris; Hansen, Axel Kornerup

    2013-01-01

    An increasing number of studies indicate that dairy products, including whey protein, alleviate several disorders of the metabolic syndrome. Here, we investigated the effects of whey protein isolate (whey) in mice fed a high-fat diet hypothesising that the metabolic effects of whey would be associated with changes in the gut microbiota composition. Five-week-old male C57BL/6 mice were fed a high-fat diet ad libitum for 14 weeks with the protein source being either whey or casein. Faeces were ...

  6. Whey protein reduces early life weight gain in mice fed a high-fat diet.

    OpenAIRE

    Britt Tranberg; Hellgren, Lars I; Jens Lykkesfeldt; Kristen Sejrsen; Aymeric Jeamet; Ida Rune; Merete Ellekilde; Nielsen, Dennis S.; Axel Kornerup Hansen

    2013-01-01

    An increasing number of studies indicate that dairy products, including whey protein, alleviate several disorders of the metabolic syndrome. Here, we investigated the effects of whey protein isolate (whey) in mice fed a high-fat diet hypothesising that the metabolic effects of whey would be associated with changes in the gut microbiota composition. Five-week-old male C57BL/6 mice were fed a high-fat diet ad libitum for 14 weeks with the protein source being either whey or casein. Faeces were ...

  7. Ranolazine inhibits voltage-gated mechanosensitive sodium channels in human colon circular smooth muscle cells.

    Science.gov (United States)

    Neshatian, Leila; Strege, Peter R; Rhee, Poong-Lyul; Kraichely, Robert E; Mazzone, Amelia; Bernard, Cheryl E; Cima, Robert R; Larson, David W; Dozois, Eric J; Kline, Crystal F; Mohler, Peter J; Beyder, Arthur; Farrugia, Gianrico

    2015-09-15

    Human jejunum smooth muscle cells (SMCs) and interstitial cells of Cajal (ICCs) express the SCN5A-encoded voltage-gated, mechanosensitive sodium channel NaV1.5. NaV1.5 contributes to small bowel excitability, and NaV1.5 inhibitor ranolazine produces constipation by an unknown mechanism. We aimed to determine the presence and molecular identity of Na(+) current in the human colon smooth muscle and to examine the effects of ranolazine on Na(+) current, mechanosensitivity, and smooth muscle contractility. Inward currents were recorded by whole cell voltage clamp from freshly dissociated human colon SMCs at rest and with shear stress. SCN5A mRNA and NaV1.5 protein were examined by RT-PCR and Western blots, respectively. Ascending human colon strip contractility was examined in a muscle bath preparation. SCN5A mRNA and NaV1.5 protein were identified in human colon circular muscle. Freshly dissociated human colon SMCs had Na(+) currents (-1.36 ± 0.36 pA/pF), shear stress increased Na(+) peaks by 17.8 ± 1.8% and accelerated the time to peak activation by 0.7 ± 0.3 ms. Ranolazine (50 μM) blocked peak Na(+) current by 43.2 ± 9.3% and inhibited shear sensitivity by 25.2 ± 3.2%. In human ascending colon strips, ranolazine decreased resting tension (31%), reduced the frequency of spontaneous events (68%), and decreased the response to smooth muscle electrical field stimulation (61%). In conclusion, SCN5A-encoded NaV1.5 is found in human colonic circular smooth muscle. Ranolazine blocks both peak amplitude and mechanosensitivity of Na(+) current in human colon SMCs and decreases contractility of human colon muscle strips. Our data provide a likely mechanistic explanation for constipation induced by ranolazine. PMID:26185330

  8. The potassium ion channel opener NS1619 inhibits proliferation and induces apoptosis in A2780 ovarian cancer cells

    International Nuclear Information System (INIS)

    Diverse types of voltage-gated potassium (K+) channels have been shown to be involved in regulation of cell proliferation. The maxi-conductance Ca2+-activated K+ channels (BK channels) may play an important role in the progression of human cancer. To explore the role of BK channels in regulation of apoptosis in human ovarian cancer cells, the effects of the specific BK channel activator NS1619 on induction of apoptosis in A2780 cells were observed. Following treatment with NS1619, cell proliferation was measured by MTT assay. Apoptosis of A2780 cells pretreated with NS1619 was detected by agarose gel electrophoresis of cellular DNA and flow cytometry. Our data demonstrate that NS1619 inhibits the proliferation of A2780 cells in a dosage and time dependent manner IC50 = 31.1 μM, for 48 h pretreatment and induces apoptosis. Western blot analyses showed that the anti-proliferation effect of NS1619 was associated with increased expression of p53, p21, and Bax. These results indicate that BK channels play an important role in regulating proliferation of human ovarian cancer cells and may induce apoptosis through induction of p21Cip1 expression in a p53-dependent manner

  9. Preventive and ameliorating effects of citrus D-limonene on dyslipidemia and hyperglycemia in mice with high-fat diet-induced obesity.

    Science.gov (United States)

    Jing, Li; Zhang, Yu; Fan, Shengjie; Gu, Ming; Guan, Yu; Lu, Xiong; Huang, Cheng; Zhou, Zhiqin

    2013-09-01

    D-limonene is a major constituent in citrus essential oil, which is used in various foods as a flavoring agent. Recently, d-limonene has been reported to alleviate fatty liver induced by a high-fat diet. Here we determined the preventive and therapeutic effects of d-limonene on metabolic disorders in mice with high-fat diet-induced obesity. In the preventive treatment, d-limonene decreased the size of white and brown adipocytes, lowered serum triglyceride (TG) and fasting blood glucose levels, and prevented liver lipid accumulations in high-fat diet-fed C57BL/6 mice. In the therapeutic treatment, d-limonene reduced serum TG, low-density lipoprotein cholesterol (LDL-c) and fasting blood glucose levels and glucose tolerance, and increased serum high-density lipoprotein cholesterol (HDL-c) in obese mice. Using a reporter assay and gene expression analysis, we found that d-limonene activated peroxisome proliferator-activated receptor (PPAR)-α signaling, and inhibited liver X receptor (LXR)-β signaling. Our data suggest that the intake of d-limonene may benefit patients with dyslipidemia and hyperglycemia and is a potential dietary supplement for preventing and ameliorating metabolic disorders. PMID:23838456

  10. Phosphorylation of TRPC6 Channels at Thr69 Is Required for Anti-hypertrophic Effects of Phosphodiesterase 5 Inhibition*

    OpenAIRE

    Nishida, Motohiro; Watanabe, Kenta; Sato, Yoji; Nakaya, Michio; Kitajima, Naoyuki; Ide, Tomomi; Inoue, Ryuji; Kurose, Hitoshi

    2010-01-01

    Activation of Ca2+ signaling induced by receptor stimulation and mechanical stress plays a critical role in the development of cardiac hypertrophy. A canonical transient receptor potential protein subfamily member, TRPC6, which is activated by diacylglycerol and mechanical stretch, works as an upstream regulator of the Ca2+ signaling pathway. Although activation of protein kinase G (PKG) inhibits TRPC6 channel activity and cardiac hypertrophy, respectively, it is unclear whether PKG suppresse...

  11. Conjugation to polymeric chains of influenza drugs targeting M2 ion channels partially restores inhibition of drug-resistant mutants

    OpenAIRE

    Larson, Alyssa M.; Chen, Jianzhu; Klibanov, Alexander M.

    2013-01-01

    By attaching multiple copies of the influenza M2 ion channel inhibitors amantadine (1) and rimantadine (2) to polymeric chains, we endeavored to recover their potency in inhibiting drug-resistant influenza viruses. Depending on loading densities, as well as the nature of the drug, the polymer, and the spacer arm, polymer-conjugated drugs were up to 30-fold more potent inhibitors of drug-resistant strains than their monomeric parents. In particular, a 20% loading density and a short linker gro...

  12. Involvement of Nuclear Factor Kappa B in High-Fat Diet-Related Pancreatic Fibrosis in Rats

    OpenAIRE

    Yan, Ming-Xian; Ren, Hong-Bo; Kou, Yi; Meng, Min; Li, Yan-Qing

    2012-01-01

    Background/Aims High-fat diets contribute to pancreatic fibrogenesis, but the pathogenesis remains unclear. This study investigated the role of nuclear factor kappa B (NF-κB) in high-fat diet-induced pancreatic fibrosis in rats. Methods Male Wistar rats were fed a high-fat diet or standard normal chow for 20 weeks. Pancreatic fibrosis was determined by Sirius red staining. Immunohistochemical staining, reverse transcription-polymerase chain reaction and Western blotting were used to identify ...

  13. Reduction of intestinal polyp formation in min mice fed a high-fat diet with aloe vera gel extract.

    Science.gov (United States)

    Chihara, Takeshi; Shimpo, Kan; Beppu, Hidehiko; Tomatsu, Akiko; Kaneko, Takaaki; Tanaka, Miyuki; Yamada, Muneo; Abe, Fumiaki; Sonoda, Shigeru

    2013-01-01

    Aloe vera gel supercritical CO2 extract (AVGE) has been shown to contain five phytosterols, reduce visceral fat accumulation, and influence the metabolism of glucose and lipids in animal model experiments. Recent epidemiologic studies have shown that obesity is an established risk factor for several cancers including colorectal cancer. Therefore, we examined the effects of AVGE on intestinal polyp formation in Apc-deficient Min mice fed a high-fat diet. Male Min mice were divided into normal diet (ND), high fat diet (HFD), low dose AVGE (HFD+LAVGE) and high dose AVGE (HFD+HAVGE) groups. The ND group received AIN-93G diet and the latter 3 groups were given modified high-fat AIN-93G diet (HFD) for 7 weeks. AVGE was suspended in 0.5% carboxymethyl cellulose (CMC) and administered orally to mice in HFD+LAVGE and HFD+HAVGE groups every day (except on Sunday) for 7 weeks at a dose of 3.75 and 12.5 mg/kg body weight, respectively. ND and HFD groups received 0.5% CMC alone. Between weeks 4 and 7, body weights in the HFD and HFD+LAVGE groups were reduced more than those in the ND group. However, body weights were not reduced in the HFD+HAVGE group. Mice were sacrificed at the end of the experiment and their intestines were scored for polyps. No significant differences were observed in either the incidence and multiplicity of intestinal polyps (≥0.5 mm in a diameter) among the three groups fed HFD. However, when intestinal polyps were categorized by their size into 0.5-1.4, 1.5-2.4, or ≥2.5 mm, the incidence and multiplicity of large polyps (≥2.5 mm) in the intestine in the HFD+HAVGE group were significantly lower than those in the HFD group. We measured plasma lipid (triglycerides and total cholesterol) and adipocytokine [interleukin-6 and high molecular weight (HMW) adiponectin] levels as possible indicators of mechanisms of inhibition. The results showed that HMW adiponectin levels in the HFD group were significantly lower than those in the ND group. However, the

  14. L—type calcium channel blockers inhibit the development but not the expression of sensitization to morphine in mice

    Institute of Scientific and Technical Information of China (English)

    ZhanQ; ZhenJW

    2002-01-01

    The relationship between opioid actions and L-type calcium channel blockers has been well documented.However,there is no report relevant to L-type calcium channel blockers and morphinesensitization,which is suggested to be an analog of behaviors that are the characteristics of drug addiction.Here the effects of three L-type calcium channel blockers,nimodipine,nifedipine and verapamil,on morphine-induced locomotor activity,the development and the expression of sensitization to morphine were studied systematically.The results showed that both nimodipine and verapamil attenuated,while nifedipine had only a tendency to decrease morphine-induced locomotor activity.All the three drugs inhibited the development of sensitization to morphine.However,none of them showed any effects on the expression of morphine sensitization.These results indicate that blocking L-tpye calcium channel attenuates the locomotor stimulating effects of morphine and inhibits the development but not the expression of morphine-sensitization.

  15. Inhibition of KV7 channels protects against myocardial ischemia and reperfusion injury

    DEFF Research Database (Denmark)

    Hedegaard, Elise Røge; Johnsen, Jacob; Povlsen, Jonas Agerlund;

    2015-01-01

    expression of the KV7 channels in rat hearts by reverse transcriptse PCR. The effect of the KV7 channel inhibitors, XE991 and linopirdine, and the KV7 channel opener, flupirtine on myocardial IR injury in isolated hearts and coronary arteries from Wistar rats was examined. Hearts were subjected to no......Aims: KV7 channel are activated by ischemia and mediate hypoxic vasodilatation. We investigated the effect of KV7 channel modulation on cardiac ischemia and reperfusion (IR) injury and the interaction with cardioprotection by ischemic preconditioning (IPC). Methods and Results: We investigated the.......1, KV7.4 and KV7.5 were expressed in rat coronary arteries and all KV7 subtypes (KV7.1-5) in the left and right ventricles of the heart. KV7 channel blockade by XE991 and linopirdine reduced infarct size additive to infarct reduction by IPC. Flupirtine abolished infarct size reduction by IPC. In...

  16. Sex differences in neuroprotection provided by inhibition of TRPM2 channels following experimental stroke

    OpenAIRE

    Jia, Jia; Verma, Saurabh; Nakayama, Shin; Quillinan, Nidia; Grafe, Marjorie R; Hurn, Patricia D.; Herson, Paco S.

    2011-01-01

    The calcium-permeable transient receptor potential M2 (TRPM2) ion channel is activated following oxidative stress and has been implicated in ischemic damage; however, little experimental evidence exists linking TRPM2 channel activation to damage following cerebral ischemia. We directly assessed the involvement of TRPM2 channels in ischemic brain injury using pharmacological inhibitors and short-hairpin RNA (shRNA)-mediated knockdown of TRPM2 expression. Each of the four TRPM2 inhibitors teste...

  17. Inhibition of the ATP-sensitive potassium channel from mouse pancreatic β-cells by surfactants

    OpenAIRE

    Smith, Paul A.; Proks, Peter

    1998-01-01

    We have used patch-clamp methods to study the effects of the detergents, Cremophor, Tween 80 and Triton X100 on the KATP channel in the pancreatic β-cell from mouse.All three detergents blocked KATP channel activity with the following order of potency: Tween 80 (KiTriton X100 (Ki=350 nM)>Cremophor. In all cases the block was poorly reversible.Single-channel studies suggested that at low doses, the detergents act as slow blockers of the KATP channel.Unlike the block produced by tolbutamide, th...

  18. Emodin improves lipid and glucose metabolism in high fat diet-induced obese mice through regulating SREBP pathway.

    Science.gov (United States)

    Li, Jinmei; Ding, Lili; Song, Baoliang; Xiao, Xu; Qi, Meng; Yang, Qiaoling; Yang, Qiming; Tang, Xiaowen; Wang, Zhengtao; Yang, Li

    2016-01-01

    Currently, obesity has become a worldwide epidemic associated with Type 2 diabetes, dyslipidemia, cardiovascular disease and chronic metabolic diseases. Emodin is one of the active anthraquinone derivatives from Rheum palmatum and some other Chinese herbs with anti-inflammatory, anticancer and hepatoprotective properties. In the present study, we investigated the anti-obesity effects of emodin in obese mice and explore its potential pharmacological mechanisms. Male C57BL/6 mice were fed with high-fat diet for 12 weeks to induce obesity. Then the obese mice were divided into four groups randomly, HFD or emodin (40mg/kg/day and 80mg/kg/day) or lovastatin (30mg/kg/ day) for another 6 weeks. Body weight and food intake were recorded every week. At the end of the treatment, the fasting blood glucose, glucose and insulin tolerance test, serum and hepatic lipid levels were assayed. The gene expressions of liver and adipose tissues were analyzed with a quantitative PCR assay. Here, we found that emodin inhibited sterol regulatory element-binding proteins (SREBPs) transactivity in huh7 cell line. Furthermore, emodin (80mg/kg/day) treatment blocked body weight gain, decreased blood lipids, hepatic cholesterol and triglyceride content, ameliorated insulin sensitivity, and reduced the size of white and brown adipocytes. Consistently, SREBP-1 and SREBP-2 mRNA levels were significantly reduced in the liver and adipose tissue after emodin treatment. These data demonstrated that emodin could improve high-fat diet-induced obesity and associated metabolic disturbances. The underlying mechanism is probably associated with regulating SREBP pathway. PMID:26626587

  19. Chungtaejeon, a Korean fermented tea, prevents the risk of atherosclerosis in rats fed a high-fat atherogenic diet

    Institute of Scientific and Technical Information of China (English)

    Keshav Raj Paudel; Ung-Won Lee; Dong-Wook Kim

    2016-01-01

    OBJECTIVE: Hypercholesterolemia is one of the wel-established risk factors for cardiovascular mortality and morbidity in coronary heart disease. The aim of this study was to investigate the anti-atherogenic effect of Chungtaejeon (CTJ, a Korean fermented tea) aqueous extract on proliferation and migration of human aortic smooth muscle cels (HASMCs)in vivo andin vitro. METHODS: The authors used high-fat atherogenic diet (HFAD) to induce hyperlipidemia in Wistar rats inin vivoanimal experiments and used HASMCs forin vitro cel experiments. For thein vitro cel experiment, the proliferation of HASMCs was evaluated using the MTT assay. Similarly, the expression of matrix metaloproteinases (MMPs) in HASMCs was measured using gelatin zymography. Antimigratory activity of CTJ was revealed using the wound-healing model and Boyden’s chamber assay. In thein vivo experiment, CTJ was administered in three different doses for 20 d from the initiation of the HFAD. After 20 d, the serum lipid proifle and total lipid contents in liver were measured. RESULTS:Treatment with CTJ for 24 h dose-dependently inhibited the proliferation and migration of HASMCs and expression of MMP-2 in HASMCs. The oral administration of CTJ at concentrations of 200 and 400 mg/kg decreased the levels of low-density lipoprotein cholesterol, total serum cholesterol and hepatic cholesterol of HFAD-fed rats. CONCLUSION: CTJ possessed strong antiproliferative, antimigratory, as wel as lipid-lowering activities. Thus, CTJ can be considered as a therapeutic option in the treatment of high-fat diet-induced atherosclerosis.

  20. Rhinacanthus nasutus leaf improves metabolic abnormalities in high-fat diet-induced obese mice

    Directory of Open Access Journals (Sweden)

    Supaporn Wannasiri

    2016-01-01

    Conclusions: To the best of our knowledge, the present study is the first report on the impact of R. nasutus extract in improving the impaired glucose and lipid metabolism in high-fat diet-induced obesity in mice via stimulating the insulin sensitivity in the liver and adipose tissues.

  1. The adverse effects of high fat induced obesity on female reproductive cycle and hormones

    Science.gov (United States)

    Donthireddy, Laxminarasimha Reddy

    The prevalence of obesity, an established risk and progression factor for abnormal reproductive cycle and tissue damage in female mice. It leads to earlier puberty, menarche in young females and infertility. There are extensive range of consequences of obesity which includes type-2 diabetes, cardiovascular disease and insulin resistance. Obesity is the interaction between dietary intake, genes, life style and environment. The interplay of hormones estrogen, insulin, and leptin is well known on energy homeostasis and reproduction. The aim of this study is to determine the effect of high fat induced obesity on reproductive cycles and its hormonal abnormalities on mice model. Two week, 3 month and 8 month long normal (WT) and very high fat diet (VHFD) diet course is followed. When mice are fed with very high fat diet, there is a drastic increase in weight within the first week later. There was a significant (pleptin levels in 6 month VHFD treated animals. 2 week, 3 month and 6 month time interval pap smear test results showed number of cells, length of estrous cycle and phases of the estrous cycle changes with VHFD mice(n=30) compared to normal diet mice(n=10). These results also indicate that the changes in the reproductive cycles in VHFD treated female mice could be due to the changes in hormones. Histo-pathological analyses of kidney, ovary, liver, pancreas, heart and lungs showed remarkable changes in some tissue on exposure to very high fat. Highly deposited fat packets observed surrounding the hepatocytes and nerve cells.

  2. A krill oil supplemented diet suppresses hepatic steatosis in high-fat fed rats.

    Science.gov (United States)

    Ferramosca, Alessandra; Conte, Annalea; Burri, Lena; Berge, Kjetil; De Nuccio, Francesco; Giudetti, Anna Maria; Zara, Vincenzo

    2012-01-01

    Krill oil (KO) is a dietary source of n-3 polyunsaturated fatty acids, mainly represented by eicosapentaenoic acid and docosahexaenoic acid bound to phospholipids. The supplementation of a high-fat diet with 2.5% KO efficiently prevented triglyceride and cholesterol accumulation in liver of treated rats. This effect was accompanied by a parallel reduction of the plasma levels of triglycerides and glucose and by the prevention of a plasma insulin increase. The investigation of the molecular mechanisms of KO action in high-fat fed animals revealed a strong decrease in the activities of the mitochondrial citrate carrier and of the cytosolic acetyl-CoA carboxylase and fatty acid synthetase, which are both involved in hepatic de novo lipogenesis. In these animals a significant increase in the activity of carnitine palmitoyl-transferase I and in the levels of carnitine was also observed, suggesting a concomitant stimulation of hepatic fatty acid oxidation. The KO supplemented animals also retained an efficient mitochondrial oxidative phosphorylation, most probably as a consequence of a KO-induced arrest of the uncoupling effects of a high-fat diet. Lastly, the KO supplementation prevented an increase in body weight, as well as oxidative damage of lipids and proteins, which is often found in high-fat fed animals. PMID:22685607

  3. A krill oil supplemented diet suppresses hepatic steatosis in high-fat fed rats.

    Directory of Open Access Journals (Sweden)

    Alessandra Ferramosca

    Full Text Available Krill oil (KO is a dietary source of n-3 polyunsaturated fatty acids, mainly represented by eicosapentaenoic acid and docosahexaenoic acid bound to phospholipids. The supplementation of a high-fat diet with 2.5% KO efficiently prevented triglyceride and cholesterol accumulation in liver of treated rats. This effect was accompanied by a parallel reduction of the plasma levels of triglycerides and glucose and by the prevention of a plasma insulin increase. The investigation of the molecular mechanisms of KO action in high-fat fed animals revealed a strong decrease in the activities of the mitochondrial citrate carrier and of the cytosolic acetyl-CoA carboxylase and fatty acid synthetase, which are both involved in hepatic de novo lipogenesis. In these animals a significant increase in the activity of carnitine palmitoyl-transferase I and in the levels of carnitine was also observed, suggesting a concomitant stimulation of hepatic fatty acid oxidation. The KO supplemented animals also retained an efficient mitochondrial oxidative phosphorylation, most probably as a consequence of a KO-induced arrest of the uncoupling effects of a high-fat diet. Lastly, the KO supplementation prevented an increase in body weight, as well as oxidative damage of lipids and proteins, which is often found in high-fat fed animals.

  4. Effects of four Bifidobacteria on obesity in high-fat diet induced rats

    OpenAIRE

    Yin, Ya-Ni; Yu, Qiong-Fen; Fu, Nian; LIU, XIAO-WEI; Lu, Fang-Gen

    2010-01-01

    AIM: To compare the effects of four Bifidobacteria strains (Bifidobacteria L66-5, L75-4, M13-4 and FS31-12, originated from normal human intestines) on weight gain, lipid metabolism, glucose metabolism in an obese murine model induced by high-fat diet.

  5. Low carbohydrate/high-fat diet attenuates cardiac hypertrophy, remodeling, and altered gene expression in hypertension

    Science.gov (United States)

    The effects of dietary fat intake on the development of left ventricular hypertrophy and accompanying structural and molecular remodeling in response to hypertension are not understood. The present study compared the effects of a high-fat versus a low-fat diet on development of left ventricular hype...

  6. The adverse effects of high fat induced obesity on female reproductive cycle and hormones

    Science.gov (United States)

    Donthireddy, Laxminarasimha Reddy

    The prevalence of obesity, an established risk and progression factor for abnormal reproductive cycle and tissue damage in female mice. It leads to earlier puberty, menarche in young females and infertility. There are extensive range of consequences of obesity which includes type-2 diabetes, cardiovascular disease and insulin resistance. Obesity is the interaction between dietary intake, genes, life style and environment. The interplay of hormones estrogen, insulin, and leptin is well known on energy homeostasis and reproduction. The aim of this study is to determine the effect of high fat induced obesity on reproductive cycles and its hormonal abnormalities on mice model. Two week, 3 month and 8 month long normal (WT) and very high fat diet (VHFD) diet course is followed. When mice are fed with very high fat diet, there is a drastic increase in weight within the first week later. There was a significant (pcycle and phases of the estrous cycle changes with VHFD mice(n=30) compared to normal diet mice(n=10). These results also indicate that the changes in the reproductive cycles in VHFD treated female mice could be due to the changes in hormones. Histo-pathological analyses of kidney, ovary, liver, pancreas, heart and lungs showed remarkable changes in some tissue on exposure to very high fat. Highly deposited fat packets observed surrounding the hepatocytes and nerve cells.

  7. Effect of blueberries on the immune response of obese mice induced by high fat diet

    Science.gov (United States)

    Both high fat diet and obesity have been linked to impaired cell-mediated immune response. Blueberry, rich in antioxidant phytochemicals, has been shown to impact biologic functions in several tissues. However, no information is available on immune cells. We investigated whether blueberry consumptio...

  8. Impairment of mitochondrial function of rat hepatocytes by high fat diet and oxidative stress

    Czech Academy of Sciences Publication Activity Database

    Garnol, T.; Endlicher, R.; Kučera, O.; Drahota, Zdeněk; Červinková, Z.

    2014-01-01

    Roč. 63, č. 2 (2014), s. 271-274. ISSN 0862-8408 R&D Projects: GA MŠk(CZ) LL1204 Grant ostatní: Univerzita Karlova(CZ) PRVOUK P37/02 Institutional support: RVO:67985823 Keywords : hepatocytes * high fat diet * mitochondrial activities * ROS Subject RIV: ED - Physiology Impact factor: 1.293, year: 2014

  9. Apelin administration ameliorates high fat diet-induced cardiac hypertrophy and contractile dysfunction.

    Science.gov (United States)

    Ceylan-Isik, Asli F; Kandadi, Machender R; Xu, Xihui; Hua, Yinan; Chicco, Adam J; Ren, Jun; Nair, Sreejayan

    2013-10-01

    Apelin has been recognized as an adipokine that plays an important role in regulating energy metabolism and is credited with antiobesity and antidiabetic properties. This study was designed to examine the effect of exogenous apelin on obesity-associated cardiac dysfunction. Oral glucose tolerance test, echocardiography, cardiomyocyte contractile and intracellular Ca(2+) properties were assessed in adult C57BL/6J mice fed - low or a - high-fat diet for 24weeks followed by apelin treatment (100nmol/kg, i.p. for 2weeks). High-fat diet resulted in increased left ventricular diastolic and systolic diameters, and wall thickness, compromised fractional shortening, impaired cardiomyocyte mechanics (peak-shortening, maximal velocity of shortening/relengthening, and duration of shortening and relengthening) and compromised intracellular Ca(2+) handling, all of which were reconciled by apelin. Apelin treatment also reversed high fat diet-induced changes in intracellular Ca(2+) regulatory proteins, ER stress, and autophagy. In addition, microRNAs (miR) -133a, miR-208 and miR-1 which were elevated following high-fat feeding were attenuated by apelin treatment. In cultured cardiomyocytes apelin reconciled palmitic acid-induced cardiomyocyte contractile anomalies. Collectively, these data depict a pivotal role of apelin in obesity-associated cardiac contractile dysfunction, suggesting a therapeutic potential of apelin in the management of cardiac dysfunction associated with obesity. PMID:23859766

  10. Effects of high fat diet on incidence of spontaneous tumors in Wistar rats

    DEFF Research Database (Denmark)

    KRISTIANSEN, E.; Madsen, Charlotte Bernhard; Meyer, Otto A.;

    1993-01-01

    In a 2.5-year carcinogenicity study, two groups, both including male and female Wistar rats, were fed two different diets with 4% and 16% fat. In addition to 4% soybean oil, the high-fat diet contained 12% mono- and diglycerides, of which 85% was stearic acid and 13% palmitic acid. There was no...

  11. Whey protein reduces early life weight gain in mice fed a high-fat diet

    DEFF Research Database (Denmark)

    Tranberg, Britt; Hellgren, Lars; Lykkesfeldt, Jens;

    2013-01-01

    reduced weight gain in young C57BL/6 mice fed a high-fat diet compared to casein. Although the effect on weight gain ceased, whey alleviated glucose intolerance, improved insulin sensitivity and reduced plasma cholesterol. These findings could not be explained by changes in food intake or gut microbiota...

  12. Methyl donor supplementation blocks the adverse effects of maternal high fat diet on offspring physiology.

    Directory of Open Access Journals (Sweden)

    Jesselea Carlin

    Full Text Available Maternal consumption of a high fat diet during pregnancy increases the offspring risk for obesity. Using a mouse model, we have previously shown that maternal consumption of a high fat (60% diet leads to global and gene specific decreases in DNA methylation in the brain of the offspring. The present experiments were designed to attempt to reverse this DNA hypomethylation through supplementation of the maternal diet with methyl donors, and to determine whether methyl donor supplementation could block or attenuate phenotypes associated with maternal consumption of a HF diet. Metabolic and behavioral (fat preference outcomes were assessed in male and female adult offspring. Expression of the mu-opioid receptor and dopamine transporter mRNA, as well as global DNA methylation were measured in the brain. Supplementation of the maternal diet with methyl donors attenuated the development of some of the adverse effects seen in offspring from dams fed a high fat diet; including weight gain, increased fat preference (males, changes in CNS gene expression and global hypomethylation in the prefrontal cortex. Notable sex differences were observed. These findings identify the importance of balanced methylation status during pregnancy, particularly in the context of a maternal high fat diet, for optimal offspring outcome.

  13. High fat food increases gastric residence and thus thresholds for objective symptoms in allergic patients

    NARCIS (Netherlands)

    Mackie, Alan; Knulst, Andre; Le, Thuy-My; Bures, Peter; Salt, Louise; Mills, E. N. Clare; Malcolm, Paul; Andreou, Adrian; Ballmer-Weber, Barbara K.

    2012-01-01

    Scope We have tested the hypothesis that high fat foods such as chocolate induce reduced rates of gastric emptying in comparison to lower fat foods and that this can impact uptake of allergens and subsequent reactions in allergic patients. Methods and results In four volunteers, magnetic resonance i

  14. Molecular fingerprint of high fat diet induced urinary bladder metabolic dysfunction in a rat model.

    Directory of Open Access Journals (Sweden)

    Andreas Oberbach

    Full Text Available AIMS/HYPOTHESIS: Diabetic voiding dysfunction has been reported in epidemiological dimension of individuals with diabetes mellitus. Animal models might provide new insights into the molecular mechanisms of this dysfunction to facilitate early diagnosis and to identify new drug targets for therapeutic interventions. METHODS: Thirty male Sprague-Dawley rats received either chow or high-fat diet for eleven weeks. Proteomic alterations were comparatively monitored in both groups to discover a molecular fingerprinting of the urinary bladder remodelling/dysfunction. Results were validated by ELISA, Western blotting and immunohistology. RESULTS: In the proteome analysis 383 proteins were identified and canonical pathway analysis revealed a significant up-regulation of acute phase reaction, hypoxia, glycolysis, β-oxidation, and proteins related to mitochondrial dysfunction in high-fat diet rats. In contrast, calcium signalling, cytoskeletal proteins, calpain, 14-3-3η and eNOS signalling were down-regulated in this group. Interestingly, we found increased ubiquitin proteasome activity in the high-fat diet group that might explain the significant down-regulation of eNOS, 14-3-3η and calpain. CONCLUSIONS/INTERPRETATION: Thus, high-fat diet is sufficient to induce significant remodelling of the urinary bladder and alterations of the molecular fingerprint. Our findings give new insights into obesity related bladder dysfunction and identified proteins that may indicate novel pathophysiological mechanisms and therefore constitute new drug targets.

  15. Steviol reduces MDCK Cyst formation and growth by inhibiting CFTR channel activity and promoting proteasome-mediated CFTR degradation.

    Directory of Open Access Journals (Sweden)

    Chaowalit Yuajit

    Full Text Available Cyst enlargement in polycystic kidney disease (PKD involves cAMP-activated proliferation of cyst-lining epithelial cells and transepithelial fluid secretion into the cyst lumen via cystic fibrosis transmembrane conductance regulator (CFTR chloride channel. This study aimed to investigate an inhibitory effect and detailed mechanisms of steviol and its derivatives on cyst growth using a cyst model in Madin-Darby canine kidney (MDCK cells. Among 4 steviol-related compounds tested, steviol was found to be the most potent at inhibiting MDCK cyst growth. Steviol inhibition of cyst growth was dose-dependent; steviol (100 microM reversibly inhibited cyst formation and cyst growth by 72.53.6% and 38.2±8.5%, respectively. Steviol at doses up to 200 microM had no effect on MDCK cell viability, proliferation and apoptosis. However, steviol acutely inhibited forskolin-stimulated apical chloride current in MDCK epithelia, measured with the Ussing chamber technique, in a dose-dependent manner. Prolonged treatment (24 h with steviol (100 microM also strongly inhibited forskolin-stimulated apical chloride current, in part by reducing CFTR protein expression in MDCK cells. Interestingly, proteasome inhibitor, MG-132, abolished the effect of steviol on CFTR protein expression. Immunofluorescence studies demonstrated that prolonged treatment (24 h with steviol (100 microM markedly reduced CFTR expression at the plasma membrane. Taken together, the data suggest that steviol retards MDCK cyst progression in two ways: first by directly inhibiting CFTR chloride channel activity and second by reducing CFTR expression, in part, by promoting proteasomal degradation of CFTR. Steviol and related compounds therefore represent drug candidates for treatment of polycystic kidney disease.

  16. Ghrelin inhibits proliferation and increases T-type Ca2+ channel expression in PC-3 human prostate carcinoma cells

    International Nuclear Information System (INIS)

    Research highlights: → Ghrelin decreases prostate carcinoma PC-3 cells proliferation. → Ghrelin favors apoptosis in PC-3 cells. → Ghrelin increase in intracellular free Ca2+ levels in PC-3 cells. → Grelin up-regulates expression of T-type Ca2+ channels in PC-3 cells. → PC-3 cells express T-channels of the CaV3.1 and CaV3.2 subtype. -- Abstract: Ghrelin is a multifunctional peptide hormone with roles in growth hormone release, food intake and cell proliferation. With ghrelin now recognized as important in neoplastic processes, the aim of this report is to present findings from a series of in vitro studies evaluating the cellular mechanisms involved in ghrelin regulation of proliferation in the PC-3 human prostate carcinoma cells. The results showed that ghrelin significantly decreased proliferation and induced apoptosis. Consistent with a role in apoptosis, an increase in intracellular free Ca2+ levels was observed in the ghrelin-treated cells, which was accompanied by up-regulated expression of T-type voltage-gated Ca2+ channels. Interestingly, T-channel antagonists were able to prevent the effects of ghrelin on cell proliferation. These results suggest that ghrelin inhibits proliferation and may promote apoptosis by regulating T-type Ca2+ channel expression.

  17. Inhibition of small-conductance Ca2+-activated K+ channels terminates and protects against atrial fibrillation

    DEFF Research Database (Denmark)

    Diness, Jonas Goldin; Sørensen, Ulrik S; Nissen, Jakob Dahl; Al-Shahib, Baha; Grunnet, Morten; Hansen, Rie Schultz; Jespersen, Thomas

    2010-01-01

    Recently, evidence has emerged that small-conductance Ca(2+)-activated K(+) (SK) channels are predominantly expressed in the atria in a number of species including human. In rat, guinea pig, and rabbit ex vivo and in vivo models of atrial fibrillation (AF), we used 3 different SK channel inhibito...

  18. Tinospora crispa Ameliorates Insulin Resistance Induced by High Fat Diet in Wistar Rats.

    Science.gov (United States)

    Abu, Mohd Nazri; Samat, Suhana; Kamarapani, Norathirah; Nor Hussein, Fuzina; Wan Ismail, Wan Iryani; Hassan, Hamzah Fansuri

    2015-01-01

    The antidiabetic properties of Tinospora crispa, a local herb that has been used in traditional Malay medicine and rich in antioxidant, were explored based on obesity-linked insulin resistance condition. Male Wistar rats were randomly divided into four groups, namely, the normal control (NC) which received standard rodent diet, the high fat diet (HFD) which received high fat diet only, the high fat diet treated with T. crispa (HFDTC), and the high fat diet treated with orlistat (HFDO). After sixteen weeks of treatment, blood and organs were harvested for analyses. Results showed that T. crispa significantly (p < 0.05) reduced the body weight (41.14 ± 1.40%), adiposity index serum levels (4.910 ± 0.80%), aspartate aminotransferase (AST: 161 ± 4.71 U/L), alanine aminotransferase (ALT: 100.95 ± 3.10 U/L), total cholesterol (TC: 18.55 ± 0.26 mmol/L), triglycerides (TG: 3.70 ± 0.11 mmol/L), blood glucose (8.50 ± 0.30 mmo/L), resistin (0.74 ± 0.20 ng/mL), and leptin (17.428 ± 1.50 ng/mL) hormones in HFDTC group. The insulin (1.65 ± 0.07 pg/mL) and C-peptide (136.48 pmol/L) hormones were slightly decreased but within normal range. The histological results showed unharmed and intact liver tissues in HFDTC group. As a conclusion, T. crispa ameliorates insulin resistance-associated with obesity in Wistar rats fed with high fat diet. PMID:25821506

  19. Tinospora crispa Ameliorates Insulin Resistance Induced by High Fat Diet in Wistar Rats

    Directory of Open Access Journals (Sweden)

    Mohd Nazri Abu

    2015-01-01

    Full Text Available The antidiabetic properties of Tinospora crispa, a local herb that has been used in traditional Malay medicine and rich in antioxidant, were explored based on obesity-linked insulin resistance condition. Male Wistar rats were randomly divided into four groups, namely, the normal control (NC which received standard rodent diet, the high fat diet (HFD which received high fat diet only, the high fat diet treated with T. crispa (HFDTC, and the high fat diet treated with orlistat (HFDO. After sixteen weeks of treatment, blood and organs were harvested for analyses. Results showed that T. crispa significantly (p < 0.05 reduced the body weight (41.14 ± 1.40%, adiposity index serum levels (4.910 ± 0.80%, aspartate aminotransferase (AST: 161 ± 4.71 U/L, alanine aminotransferase (ALT: 100.95 ± 3.10 U/L, total cholesterol (TC: 18.55 ± 0.26 mmol/L, triglycerides (TG: 3.70 ± 0.11 mmol/L, blood glucose (8.50 ± 0.30 mmo/L, resistin (0.74 ± 0.20 ng/mL, and leptin (17.428 ± 1.50 ng/mL hormones in HFDTC group. The insulin (1.65 ± 0.07 pg/mL and C-peptide (136.48 pmol/L hormones were slightly decreased but within normal range. The histological results showed unharmed and intact liver tissues in HFDTC group. As a conclusion, T. crispa ameliorates insulin resistance-associated with obesity in Wistar rats fed with high fat diet.

  20. Enhanced susceptibility of cyclin kinase inhibitor p21 knockout mice to high fat diet induced atherosclerosis

    Directory of Open Access Journals (Sweden)

    Khanna Ashwani K

    2009-07-01

    Full Text Available Abstract Cyclin kinase inhibitor p21 is one of the most potent inhibitors of aortic smooth muscle cell proliferation, a key mediator of atherosclerosis. This study tests if p2l deficiency will result in severe atherosclerosis in a mouse model. p21-/- and strain matched wild type mice were fed with high fat diet for 21 weeks. Analysis for biochemical parameters (cholesterol, triglycerides in serum and mRNA expression of CD36, HO-1, TGF-β, IFN-γ, TNF-α, PPAR-γ and NADPH oxidase components (p22phox, NOX-1 and Rac-1 was performed in aortic tissues by Real Time PCR. p21-/- mice gained significantly (p -/- compared to wild type mice fed with high fat diet. High fat diet resulted in significantly decreased TGF-β (p -/- mice compared to animal fed with regular diet. IFN-γ mRNA expression (235 ± 11 folds increased significantly in high fat diet fed p21-/- mice and a multifold modulation of PPAR-γ(136 ± 7, p22phox, NOX-1 and Rac-1 (15–35-folds mRNA in aortic tissues from p21-/- mice compared to the wild type mice. Severity of atherosclerotic lesions was significantly higher in p21-/- compared to wild type mice. The results demonstrate that the deficiency of p21 leads to altered expression of pro-atherogenic genes, and severe atherosclerosis in mice fed with high fat diet. This opens the possibility of p21 protein as a therapeutic tool to control progression of atherosclerosis.

  1. Rock Tea extract (Jasonia glutinosa) relaxes rat aortic smooth muscle by inhibition of L-type Ca(2+) channels.

    Science.gov (United States)

    Valero, Marta Sofía; Oliván-Viguera, Aida; Garrido, Irene; Langa, Elisa; Berzosa, César; López, Víctor; Gómez-Rincón, Carlota; Murillo, María Divina; Köhler, Ralf

    2015-12-01

    In traditional herbal medicine, Rock Tea (Jasonia glutinosa) is known for its prophylactic and therapeutic value in various disorders including arterial hypertension. However, the mechanism by which Rock Tea exerts blood pressure-lowering actions has not been elucidated yet. Our aim was to demonstrate vasorelaxing effects of Rock Tea extract and to reveal its possible action mechanism. Isometric myography was conducted on high-K+-precontracted rings from rat thoracic aorta and tested extracts at concentrations of 0.5-5 mg/ml. Whole-cell patch-clamp experiments were performed in rat aortic vascular smooth muscle cells (line A7r5) to determine blocking effects on L-type Ca(2+) channels. Rock Tea extract relaxed the aorta contracted by high [K+] concentration dependently with an EC50 of ≈2.4 mg/ml and produced ≈75 % relaxation at the highest concentration tested. The L-type Ca(2+) channel blocker, verapamil (10(-6) M), had similar effects. Rock Tea extract had no effect in nominally Ca(2+)-free high-K(+) buffer but significantly inhibited contractions to re-addition of Ca(2+). Rock Tea extract inhibited the contractions induced by the L-type Ca(2+) channel activator Bay K 8644 (10(-5) M) and by phenylephrine (10(-6) M). Rock Tea extract and Y-27632 (10(-6) M), Rho-kinase inhibitor, had similar effects and the respective effects were not additive. Patch-clamp experiments demonstrated that Rock Tea extract (2.5 mg/ml) virtually abolished L-type Ca(2+) currents in A7r5. We conclude that Rock Tea extract produced vasorelaxation of rat aorta and that this relaxant effect is mediated by inhibition of L-type Ca(2+) channels. Rock Tea extracts may be of phytomedicinal value for prevention and adjuvant treatment of hypertension and other cardiovascular diseases. PMID:26464340

  2. High glucose inhibits ClC-2 chloride channels and attenuates cell migration of rat keratinocytes

    Directory of Open Access Journals (Sweden)

    Pan F

    2015-08-01

    Full Text Available Fuqiang Pan, Rui Guo, Wenguang Cheng, Linlin Chai, Wenping Wang, Chuan Cao, Shirong LiDepartment of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, People’s Republic of China Background: Accumulating evidence has demonstrated that migration of keratinocytes is critical to wound epithelialization, and defects of this function result in chronic delayed-healing wounds in diabetes mellitus patients, and the migration has been proved to be associated with volume-activated chloride channels. The aim of the study is to investigate the effects of high glucose (HG, 25 mM on ClC-2 chloride channels and cell migration of keratinocytes.Methods: Newborn Sprague Dawley rats were used to isolate and culture the keratinocyte in this study. Immunofluorescence assay, real-time polymerase chain reaction, and Western blot assay were used to examine the expression of ClC-2 protein or mRNA. Scratch wound assay was used to measure the migratory ability of keratinocytes. Transwell cell migration assay was used to measure the invasion and migration of keratinocytes. Recombinant lentivirus vectors were established and transducted to keratinocytes. Whole-cell patch clamp was used to perform the electrophysiological studies.Results: We found that the expression of ClC-2 was significantly inhibited when keratinocytes were exposed to a HG (25 mM medium, accompanied by the decline of volume-activated Cl- current (ICl,vol, migration potential, and phosphorylated PI3K as compared to control group. When knockdown of ClC-2 by RNAi or pretreatment with wortmannin, similar results were observed, including ICl,vol and migration keratinocytes were inhibited.Conclusion: Our study proved that HG inhibited ClC-2 chloride channels and attenuated cell migration of rat keratinocytes via inhibiting PI3K signaling.Keywords: high glucose, keratinocytes, ClC-2, cell migration, PI3K

  3. Neuroprotective Effects of Endurance Exercise Against High-Fat Diet-Induced Hippocampal Neuroinflammation.

    Science.gov (United States)

    Kang, E-B; Koo, J-H; Jang, Y-C; Yang, C-H; Lee, Y; Cosio-Lima, L M; Cho, J-Y

    2016-05-01

    Obesity contributes to systemic inflammation, which is associated with the varied pathogenesis of neurodegenerative diseases. Growing evidence has demonstrated that endurance exercise (EE) mitigates obesity-induced brain inflammation. However, exercise-mediated anti-inflammatory mechanisms remain largely unknown. We investigated how treadmill exercise (TE) reverses obesity-induced brain inflammation, mainly focusing on toll-like receptor-4 (TLR-4)-dependent neuroinflammation in the obese rat brain after 20 weeks of a high-fat diet (HFD). TE in HFD-fed rats resulted in a significant lowering in the homeostasis model assessment of insulin resistance index, the area under the curve for glucose and abdominal visceral fat, and also improved working memory ability in a passive avoidance task relative to sedentary behaviour in HFD-fed rats, with the exception of body weight. More importantly, TE revoked the increase in HFD-induced proinflammatory cytokines (tumour necrosis factor α and interleukin-1β) and cyclooxygenase-2, which is in parallel with a reduction in TLR-4 and its downstream proteins, myeloid differentiation 88 and tumour necrosis factor receptor associated factor 6, and phosphorylation of transforming growth factor β-activated kinase 1, IkBα and nuclear factor-κB. Moreover, TE reduced an indicator of microglia activation, ionised calcium-binding adapter molecule-1, and also decreased glial fibrillary acidic protein, an indicator of gliosis formed by activated astrocytes in the cerebral cortex and the hippocampal dentate gyrus, compared to HFD-fed sedentary rats. Finally, EE up-regulated the expression of anti-apoptotic protein, Bcl-2, and suppressed the expression of pro-apoptotic protein, Bax, in the hippocampus compared to HFD-fed sedentary rats. Taken together, these data suggest that TE may exert neuroprotective effects as a result of mitigating the production of proinflammatory cytokines by inhibiting the TLR4 signalling pathways. The results of

  4. Voltage-independent inhibition of Cav2.2 channels is delimited to a specific region of the membrane potential in rat SCG neurons

    Institute of Scientific and Technical Information of China (English)

    Oscar Vivas; Isabel Arenas; David E.García

    2012-01-01

    Neurotransmitters and hormones regulate Cav2.2 channels through a voltage-independent pathway which is not well understood.It has been suggested that this voltageindependent inhibition is constant at all membrane voltages.However,changes in the percent of voltageindependent inhibition of Cav2.2 have not been tested within a physiological voltage range.Here,we used a double-pulse protocol to isolate the voltage-independent inhibition of Cav2.2 channels induced by noradrenaline in rat superior cervical ganglion neurons.To assess changes in the percent of the voltage-independent inhibition,the activation voltage of the channels was tested between -40 and +40 mV.We found that the percent of voltage-independent inhibition induced by noradrenaline changed with the activation voltage used.In addition,voltage-independent inhibition induced by oxo-M,a muscarinic agonist,exhibited thesame dependence on activation voltage,which supports that this pattern is not exclusive for adrenergic activation.Our results suggested that voltage-independent inhibition of Cav2.2 channels depends on the activation voltage of the channel in a physiological voltage range.This may have relevant implications in the understanding of the mechanism involved in voltage-independent inhibition.

  5. Monoclonal antibodies to the apical chloride channel in Necturus gallbladder inhibit the chloride conductance.

    OpenAIRE

    Finn, A L; Tsai, L M; Falk, R J

    1989-01-01

    Monoclonal antibodies raised by injecting Necturus gallbladder cells into mice were tested for their ability to inhibit the apical chloride conductance induced by elevation of cellular cAMP. Five of these monoclonal antibodies bound to the apical cells, as shown by indirect immunofluorescence microscopy, and inhibited the chloride conductance; one antibody that bound only to subepithelial smooth muscle, by indirect immunofluorescence microscopy, showed no inhibition of chloride transport. The...

  6. Inhibition of the cardiac Na(+) channel α-subunit Nav1.5 by propofol and dexmedetomidine.

    Science.gov (United States)

    Stoetzer, Carsten; Reuter, Svenja; Doll, Thorben; Foadi, Nilufar; Wegner, Florian; Leffler, Andreas

    2016-03-01

    Propofol and dexmedetomidine are very commonly used sedative agents. However, several case reports demonstrated cardiovascular adverse effects of these two sedatives. Both substances were previously demonstrated to quite potently inhibit neuronal voltage-gated Na(+) channels. Thus, a possible molecular mechanism for some of their cardiac side effects is an inhibition of cardiac voltage gated Na(+) channels. In this study, we therefore explored the effects of propofol and dexmedetomidine on the cardiac predominant Na(+) channel α-subunit Nav1.5. Effects of propofol and dexmedetomidine were investigated on constructs of the human α-subunit Nav1.5 stably expressed in HEK-293 cells by means of whole-cell patch clamp recordings. Both agents induced a concentration-dependent tonic inhibition of Nav1.5. The calculated IC50 value for propofol was 228 ± 10 μM, and for dexmedetomidine 170 ± 20 μM. Tonic block only marginally increased on inactivated channels, and a weak use-dependent block at 10 Hz was observed for dexmedetomidine (16 ± 2 % by 100 μM). The voltage dependencies of fast and slow inactivation as well as the time course of recovery from inactivation were shifted by both propofol and dexmedetomidine. Propofol (IC50 126 ± 47 μM) and dexmedetomidine (IC50 182 ± 27 μM) blocked the persistent sodium current induced by veratradine. Finally, the local-anesthetic (LA)-insensitive mutant Nav1.5-F1760A exhibited reduced tonic and use-dependent block by both substances. Dexmedetomidine was generally more potent as compared to propofol. Propofol and dexmedetomidine seem to interact with the LA-binding site to inhibit the cardiac Na(+) channel Nav1.5 in a state-dependent manner. These data suggest that Nav1.5 is a hitherto unrecognized molecular component of some cardiovascular side effects of these sedative agents. PMID:26667357

  7. INVESTIGATION OF SEIZURE ACTIVITY AFTER CYCLIC NUCLEOTIDE PHOSPHODIESTERASE INHIBITION WITH SECOND MESSENGER AND CALCIUM ION CHANNEL INHIBITION IN MICE

    Directory of Open Access Journals (Sweden)

    J Nandhakumar

    2012-03-01

    Full Text Available The role of PDE-4 inhibitor etazolate, was evaluated in the presence of PDE-7 inhibitor, BRL-50481, in animal models of epilepsy. Seizures were induced in the animals by subjecting them to injection of chemical convulsants, Pilocarpine, Kainic acid (KA and maximal electroshock (MES. The combination of etazolate and BRL50481 treated mice showed a significant (P<0.001 quick onset of action, jerky movements and convulsion when compared to gabapentin. The combination of etazolate and sGC inhibitor, methylene blue (MB treated mice showed a significant (P<0.001 delay in onset of action, jerky movements and convulsion when compare to gabapentin as well as against the combination of etazolate with BRL 50481.The present study mainly highlights the individual effects of etazolate and combination with BRL-50481 potentiates (P<0.001 the onset of seizure activity against all models of convulsion. The study mainly comprises the onset of seizures, mortality/recovery, percentage of prevention of seizures (anticonvulsant and total duration of convulsive time. The total convulsive time was prolonged significantly (P<0.05 and P<0.01 in combination of methylene blue with etazolate treated (28.59% and 35.15 % groups, compared to DMSO received group (100% in the MES model. In the same way, the combination of calcium channel modulator (CCM and calcium channel blocker (CCB amiodarone and nifedipine respectively, with etazolate showed a significant (P<0.001 delay in onset of seizures, compared to DMSO and etazolate treated groups in all models of epilepsy. This confirms that both CCM and CCB possess anticonvulsant activity. Finally, the study reveals that identification of new cAMP mediated phosphodiesterases family members offers a potential new therapy for epilepsy management in future.

  8. Ferritin Ion Channel Disorder Inhibits Fe(II)/O2 Reactivity at Distant Sites

    OpenAIRE

    Tosha, Takehiko; Behera, Rabindra K.; Theil, Elizabeth C.

    2012-01-01

    Ferritins, a complex, mineralized, protein nanocage family essential for life, provide iron concentrates and oxidant protection. Protein based ion channels and Fe(II)/O2 catalysis initiate conversion of thousands of Fe atoms to caged, ferritin Fe2O3•H2O minerals. The ion channels consist of six helical segments, contributed by 3 of 12 or 24 polypeptide subunits, around the three-fold cage axes. The channel structure guides entering Fe(II) ions toward multiple, catalytic, diiron sites buried i...

  9. Proinsulin-producing, hyperglycemia-induced adipose tissue macrophages underlie insulin resistance in high fat-fed diabetic mice

    Science.gov (United States)

    Adipose tissue macrophages play an important role in the pathogenesis of obese type 2 diabetes. High-fat diet-induced obesity has been shown to lead to adipose tissue macrophages accumulation in rodents;however, the impact of hyperglycemia on adipose tissue macrophages dynamics in high-fat diet-fed ...

  10. Amplified Cold Transduction in Native Nociceptors by M-Channel Inhibition

    Czech Academy of Sciences Publication Activity Database

    Vetter, I.; Hein, A.; Sattler, S.; Hessler, S.; Touška, Filip; Bressan, E.; Parra, A.; Hager, U.; Leffler, A.; Boukalová, Štěpána; Nissen, M.; Lewis, R. J.; Belmonte, C.; Alzheimer, Ch.; Huth, T.; Vlachová, Viktorie; Reeh, P. W.; Zimmermann, K.

    2013-01-01

    Roč. 33, č. 42 (2013), s. 16627-16641. ISSN 0270-6474 Institutional support: RVO:67985823 Keywords : nociceptor * channels of HEK293T * receptor TRPM8 Subject RIV: ED - Physiology Impact factor: 6.747, year: 2013

  11. 5,6-EET potently inhibits T-type calcium channels

    DEFF Research Database (Denmark)

    Cazade, M.; Bidaud, I.; Hansen, Pernille B. Lærkegaard;

    2014-01-01

    T-type calcium channels (T-channels) are important actors in neuronal pacemaking, in heart rhythm, and in the control of the vascular tone. T-channels are regulated by several endogenous lipids including the primary eicosanoid arachidonic acid (AA), which display an important role in vasodilation...... the three human recombinant T-channels (Ca(v)3.1, Ca(v)3.2, and Ca(v)3.3), as compared to those of AA. We identified the P450 epoxygenase product, 5,6-EET, as a potent physiological inhibitor of Ca(v)3 currents. The effects of 5,6-EET were observed at sub-micromolar concentrations (IC50 = 0.54 mu M...

  12. Portulaca oleracea inhibit vincristine induced peripheral neuropathy: involvement of ATP-sensitive K+ channels

    Directory of Open Access Journals (Sweden)

    L. Mohana Rupa

    2014-06-01

    Conclusion: The results of the present study reveal the antinociceptive effect of P. oleracea in vincristine induced peripheral neuropathy and involving ATP-sensitive potassium channels pathway. [Int J Basic Clin Pharmacol 2014; 3(3.000: 474-478

  13. Inhibition of G Protein-Activated Inwardly Rectifying K+ Channels by Phencyclidine

    OpenAIRE

    Kobayashi, Toru; Nishizawa, Daisuke; Ikeda, Kazutaka

    2011-01-01

    Addictive drugs, such as opioids, ethanol, cocaine, amphetamine, and phencyclidine (PCP), affect many functions of the nervous system and peripheral organs, resulting in severe health problems. G protein-activated inwardly rectifying K+ (GIRK, Kir3) channels play an important role in regulating neuronal excitability through activation of various Gi/o protein-coupled receptors including opioid and CB1 cannabinoid receptors. Furthermore, the channels are directly activated by ethanol and inhibi...

  14. Severe Maternal Hyperglycemia Exacerbates the Development of Insulin Resistance and Fatty Liver in the Offspring on High Fat Diet

    Directory of Open Access Journals (Sweden)

    Yong Song

    2012-01-01

    Full Text Available Background. Adverse maternal environments may predispose the offspring to metabolic syndrome in adulthoods, but the underlying mechanism has not been fully understood. Methods. Maternal hyperglycemia was induced by streptozotocin (STZ injection while control (CON rats received citrate buffer. Litters were adjusted to eight pups per dam and then weaned to standard diet. Since 13 weeks old, a subset of offspring from STZ and CON dams were switched to high fat diet (HFD for another 13 weeks. Glucose and insulin tolerance tests (GTT and ITT and insulin secretion assay were performed; serum levels of lipids and leptin were measured. Hepatic fat accumulation and islet area were evaluated through haematoxylin and eosin staining. Results. STZ offspring exhibited lower survival rate, lower birth weights, and growth inhibition which persisted throughout the study. STZ offspring on HFD showed more severe impairment in GTT and ITT, and more profound hepatic steatosis and more severe hyperlipidemia compared with CON-HFD rats. Conclusions. Offspring from diabetic dams would be prone to exhibit low birth weight and postnatal growth inhibition, but could maintain normal glucose tolerance and insulin sensitivity. HFD accelerates development of insulin resistance in the offspring of diabetic dams mainly via a compensatory response of islets.

  15. Characterization of an alcoholic hepatic steatosis model induced by ethanol and high-fat diet in rats

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Alves de Souza

    2015-06-01

    Full Text Available Alcoholic liver disease is characterized by a wide spectrum of liver damage, which increases when ethanol is associated with high-fat diets (HFD. This work aimed to establish a model of alcoholic hepatic steatosis (AHS by using a combination of 10% ethanol and sunflower seeds as the source of HFD. Male rats received water or 10% ethanol and regular chow diet and/or HFD, which consisted of sunflower seeds. The food consumption, liquid intake and body weight of the rats were monitored for 30 days. After this period, blood was collected for biochemical evaluation, and liver samples were collected for histological, mitochondrial enzyme activity and oxidative stress analyses. Our results indicated that the combination of 10% ethanol and HFD induced micro- and macrosteatosis and hepatocyte tumefaction, decreased the levels of reduced glutathione and glutathione S-transferase activity and increased the level of lipoperoxidation and superoxide dismutase activity. The mitochondrial oxidation of NADH and succinate were partially inhibited. Complexes I and II were the main inhibition sites. Hepatic steatosis was successfully induced after 4 weeks of the diet, and the liver function was modified. The combination of 10% ethanol and sunflower seeds as an HFD produced an inexpensive model to study AHS in rats.

  16. The T-type calcium channel antagonist Z944 disrupts prepulse inhibition in both epileptic and non-epileptic rats.

    Science.gov (United States)

    Marks, Wendie N; Greba, Quentin; Cain, Stuart M; Snutch, Terrance P; Howland, John G

    2016-09-22

    The role of T-type calcium channels in brain diseases such as absence epilepsy and neuropathic pain has been studied extensively. However, less is known regarding the involvement of T-type channels in cognition and behavior. Prepulse inhibition (PPI) is a measure of sensorimotor gating which is a basic process whereby the brain filters incoming stimuli to enable appropriate responding in sensory rich environments. The regulation of PPI involves a network of limbic, cortical, striatal, pallidal and pontine brain areas, many of which show high levels of T-type calcium channel expression. Therefore, we tested the effects of blocking T-type calcium channels on PPI with the potent and selective T-type antagonist Z944 (0.3, 1, 3, 10mg/kg; i.p.) in adult Wistar rats and two related strains, the Genetic Absence Epilepsy Rats from Strasbourg (GAERS) and Non-Epileptic Control (NEC). PPI was tested using a protocol that varied prepulse intensity (3, 6, and 12dB above background) and prepulse-pulse interval (30, 50, 80, 140ms). Z944 decreased startle in the Wistar strain at the highest dose relative to lower doses. Z944 dose-dependently disrupted PPI in the Wistar and GAERS strains with the most potent effect observed with the higher doses. These findings suggest that T-type calcium channels contribute to normal patterns of brain activity that regulate PPI. Given that PPI is disrupted in psychiatric disorders, future experiments that test the specific brain regions involved in the regulation of PPI by T-type calcium channels may help inform therapeutic development for those suffering from sensorimotor gating impairments. PMID:27365170

  17. Nordihydroguaiaretic acid protects against high-fat diet-induced fatty liver by activating AMP-activated protein kinase in obese mice

    International Nuclear Information System (INIS)

    Research highlights: → NDGA decreases high-fat diet-induced body weight gain and adiposity. → NDGA reduces high-fat diet-induced triglyceride accumulation in liver. → NDGA improves lipid storage in vitro through altering lipid regulatory proteins. → Inhibition of lipid storage in vivo and in vitro is mediated by AMPK activation. -- Abstract: Nonalcoholic fatty liver disease, one of the most common causes of chronic liver disease, is strongly associated with metabolic syndrome. Nordihydroguaiaretic acid (NDGA) has been reported to inhibit lipoprotein lipase; however, the effect of NDGA on hepatic lipid metabolism remains unclear. We evaluated body weight, adiposity, liver histology, and hepatic triglyceride content in high-fat diet (HFD)-fed C57BL/6J mice treated with NDGA. In addition, we characterized the underlying mechanism of NDGA's effects in HepG2 hepatocytes by Western blot and RT-PCR analysis. NDGA (100 or 200 mg/kg/day) reduced weight gain, fat pad mass, and hepatic triglyceride accumulation, and improved serum lipid parameters in mice fed a HFD for 8 weeks. NDGA significantly increased AMP-activated protein kinase (AMPK) phosphorylation in the liver and in HepG2 hepatocytes. NDGA downregulated the level of mature SREBP-1 and its target genes (acetyl-CoA carboxylase and fatty acid synthase), but, it upregulated expression of genes involved in fatty acid oxidation, such as peroxisome proliferator-activated receptor (PPAR)α, PPARγ coactivator-1, carnitine palmitoyl transferase-1, and uncoupling protein-2. The specific AMPK inhibitor compound C attenuated the effects of NDGA on expression of lipid metabolism-related proteins in HepG2 hepatocytes. The beneficial effects of NDGA on HFD-induced hepatic triglyceride accumulation are mediated through AMPK signaling pathways, suggesting a potential target for preventing NAFLD.

  18. Nordihydroguaiaretic acid protects against high-fat diet-induced fatty liver by activating AMP-activated protein kinase in obese mice

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Myoung-Su; Kim, Daeyoung; Jo, Keunae [Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, 262 Seongsanno, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Hwang, Jae-Kwan, E-mail: jkhwang@yonsei.ac.kr [Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, 262 Seongsanno, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Translational Research Center for Protein Function Control, Yonsei University, 262 Seongsanno, Seodaemun-gu, Seoul 120-749 (Korea, Republic of)

    2010-10-08

    Research highlights: {yields} NDGA decreases high-fat diet-induced body weight gain and adiposity. {yields} NDGA reduces high-fat diet-induced triglyceride accumulation in liver. {yields} NDGA improves lipid storage in vitro through altering lipid regulatory proteins. {yields} Inhibition of lipid storage in vivo and in vitro is mediated by AMPK activation. -- Abstract: Nonalcoholic fatty liver disease, one of the most common causes of chronic liver disease, is strongly associated with metabolic syndrome. Nordihydroguaiaretic acid (NDGA) has been reported to inhibit lipoprotein lipase; however, the effect of NDGA on hepatic lipid metabolism remains unclear. We evaluated body weight, adiposity, liver histology, and hepatic triglyceride content in high-fat diet (HFD)-fed C57BL/6J mice treated with NDGA. In addition, we characterized the underlying mechanism of NDGA's effects in HepG2 hepatocytes by Western blot and RT-PCR analysis. NDGA (100 or 200 mg/kg/day) reduced weight gain, fat pad mass, and hepatic triglyceride accumulation, and improved serum lipid parameters in mice fed a HFD for 8 weeks. NDGA significantly increased AMP-activated protein kinase (AMPK) phosphorylation in the liver and in HepG2 hepatocytes. NDGA downregulated the level of mature SREBP-1 and its target genes (acetyl-CoA carboxylase and fatty acid synthase), but, it upregulated expression of genes involved in fatty acid oxidation, such as peroxisome proliferator-activated receptor (PPAR){alpha}, PPAR{gamma} coactivator-1, carnitine palmitoyl transferase-1, and uncoupling protein-2. The specific AMPK inhibitor compound C attenuated the effects of NDGA on expression of lipid metabolism-related proteins in HepG2 hepatocytes. The beneficial effects of NDGA on HFD-induced hepatic triglyceride accumulation are mediated through AMPK signaling pathways, suggesting a potential target for preventing NAFLD.

  19. Combination of Ca2+-activated K+ channel blockers inhibits acetylcholine-evoked nitric oxide release in rat superior mesenteric artery

    Science.gov (United States)

    Stankevičius, E; Lopez-Valverde, V; Rivera, L; Hughes, A D; Mulvany, M J; Simonsen, Ulf

    2006-01-01

    Background and purpose: The present study investigated whether calcium-activated K+ channels are involved in acetylcholine-evoked nitric oxide (NO) release and relaxation. Experimental approach: Simultaneous measurements of NO concentration and relaxation were performed in rat superior mesenteric artery and endothelial cell membrane potential and intracellular calcium ([Ca2+]i) were measured. Key results. A combination of apamin plus charybotoxin, which are, respectively, blockers of small-conductance and of intermediate- and large-conductance Ca2+-activated K channels abolished acetylcholine (10 μM)-evoked hyperpolarization of endothelial cell membrane potential. Acetylcholine-evoked NO release was reduced by 68% in high K+ (80 mM) and by 85% in the presence of apamin plus charybdotoxin. In noradrenaline-contracted arteries, asymmetric dimethylarginine (ADMA), an inhibitor of NO synthase inhibited acetylcholine-evoked NO release and relaxation. However, only further addition of oxyhaemoglobin or apamin plus charybdotoxin eliminated the residual acetylcholine-evoked NO release and relaxation. Removal of extracellular calcium or an inhibitor of calcium influx channels, SKF96365, abolished acetylcholine-evoked increase in NO concentration and [Ca2+]i. Cyclopiazonic acid (CPA, 30 μM), an inhibitor of sarcoplasmic Ca2+-ATPase, caused a sustained NO release in the presence, but only a transient increase in the absence, of extracellular calcium. Incubation with apamin and charybdotoxin did not change acetylcholine or CPA-induced increases in [Ca2+]i, but inhibited the sustained NO release induced by CPA. Conclusions and Implications: Acetylcholine increases endothelial cell [Ca2+]i by release of stored calcium and calcium influx resulting in activation of apamin and charybdotoxin-sensitive K channels, hyperpolarization and release of NO in the rat superior mesenteric artery. PMID:16967048

  20. Ferritin ion channel disorder inhibits Fe(II)/O2 reactivity at distant sites.

    Science.gov (United States)

    Tosha, Takehiko; Behera, Rabindra K; Theil, Elizabeth C

    2012-11-01

    Ferritins, a complex, mineralized, protein nanocage family essential for life, provide iron concentrates and oxidant protection. Protein-based ion channels and Fe(II)/O(2) catalysis initiate conversion of thousands of Fe atoms to caged, ferritin Fe(2)O(3)·H(2)O minerals. The ion channels consist of six helical segments, contributed by 3 of 12 or 24 polypeptide subunits, around the 3-fold cage axes. The channel structure guides entering Fe(II) ions toward multiple, catalytic, diiron sites buried inside ferritin protein helices, ~20 Å away from channel internal exits. The catalytic product, Fe(III)-O(H)-Fe(III), is a mineral precursor; mineral nucleation begins inside the protein cage with mineral growth in the central protein cavity (5-8 nm diameter). Amino acid substitutions that changed ionic or hydrophobic channel interactions R72D, D122R, and L134P increased ion channel structural disorder (protein crystallographic analyses) and increased Fe(II) exit [chelated Fe(II) after ferric mineral reduction/dissolution]. Since substitutions of some channel carboxylate residues diminished ferritin catalysis with no effect on Fe(II) exit, such as E130A and D127A, we investigated catalysis in ferritins with altered Fe(II) exit, R72D, D122R and L134P. The results indicate that simply changing the ionic properties of the channels, as in the R72D variant, need not change the forward catalytic rate. However, both D122R and L134P, which had dramatic effects on ferritin catalysis, also caused larger effects on channel structure and order, contrasting with R72D. All three amino acid substitutions, however, decreased the stability of the catalytic intermediate, diferric peroxo, even though overall ferritin cage structure is very stable, resisting 80 °C and 6 M urea. The localized structural changes in ferritin subdomains that affect ferritin function over long distances illustrate new properties of the protein cage in natural ferritin function and for applied ferritin uses. PMID

  1. Plasma PCSK9 concentrations during an oral fat load and after short term high-fat, high-fat high-protein and high-fructose diets

    Directory of Open Access Journals (Sweden)

    Cariou Bertrand

    2013-01-01

    Full Text Available Abstract Background PCSK9 (Proprotein Convertase Subtilisin Kexin type 9 is a circulating protein that promotes hypercholesterolemia by decreasing hepatic LDL receptor protein. Under non interventional conditions, its expression is driven by sterol response element binding protein 2 (SREBP2 and follows a diurnal rhythm synchronous with cholesterol synthesis. Plasma PCSK9 is associated to LDL-C and to a lesser extent plasma triglycerides and insulin resistance. We aimed to verify the effect on plasma PCSK9 concentrations of dietary interventions that affect these parameters. Methods We performed nutritional interventions in young healthy male volunteers and offspring of type 2 diabetic (OffT2D patients that are more prone to develop insulin resistance, including: i acute post-prandial hyperlipidemic challenge (n=10, ii 4 days of high-fat (HF or high-fat/high-protein (HFHP (n=10, iii 7 (HFruc1, n=16 or 6 (HFruc2, n=9 days of hypercaloric high-fructose diets. An acute oral fat load was also performed in two patients bearing the R104C-V114A loss-of-function (LOF PCSK9 mutation. Plasma PCSK9 concentrations were measured by ELISA. For the HFruc1 study, intrahepatocellular (IHCL and intramyocellular lipids were measured by 1H magnetic resonance spectroscopy. Hepatic and whole-body insulin sensitivity was assessed with a two-step hyperinsulinemic-euglycemic clamp (0.3 and 1.0 mU.kg-1.min-1. Findings HF and HFHP short-term diets, as well as an acute hyperlipidemic oral load, did not significantly change PCSK9 concentrations. In addition, post-prandial plasma triglyceride excursion was not altered in two carriers of PCSK9 LOF mutation compared with non carriers. In contrast, hypercaloric 7-day HFruc1 diet increased plasma PCSK9 concentrations by 28% (p=0.05 in healthy volunteers and by 34% (p=0.001 in OffT2D patients. In another independent study, 6-day HFruc2 diet increased plasma PCSK9 levels by 93% (p Conclusions Plasma PCSK9 concentrations vary

  2. Endoplasmic reticulum stress involved in high-fat diet and palmitic acid-induced vascular damages and fenofibrate intervention

    International Nuclear Information System (INIS)

    Fenofibrate (FF) is widely used to lower blood lipids in clinical practice, but whether its protective effect on endothelium-dependent vasodilatation (EDV) in thoracic aorta is related with endoplasmic reticulum (ER) stress remains unknown. In this study, female Sprauge Dawley rats were divided into standard chow diets (SCD), high-fat diets (HFD) and HFD plus FF treatment group (HFD + FF) randomly. The rats of latter two groups were given HFD feeding for 5 months, then HFD + FF rats were treated with FF (30 mg/kg, once daily) via gavage for another 2 months. The pathological and tensional changes, protein expression of eNOS, and ER stress related genes in thoracic aorta were measured. Then impacts of palmitic acid (PA) and FF on EDV of thoracic aorta from normal female SD rats were observed. Ultimately the expression of ER stress related genes were assessed in primary mouse aortic endothelial cells (MAEC) treated by fenofibric acid (FA) and PA. We found that FF treatment improved serum lipid levels and pathological changes in thoracic aorta, accompanied with decreased ER stress and increased phosphorylation of eNOS. FF pretreatment also improved EDV impaired by different concentrations of PA treatment. The dose- and time-dependent inhibition of cell proliferation by PA were inverted by FA pretreatment. Phosphorylation of eNOS and expression of ER stress related genes were all inverted by FA pretreatment in PA-treated MAEC. Our findings show that fenofibrate recovers damaged EDV by chronic HFD feeding and acute stimulation of PA, this effect is related with decreased ER stress and increased phosphorylation of eNOS. - Highlights: • Fenofibrate treatment improved pathological changes in thoracic aorta by chronic high-fat-diet feeding. • Fenofibrate pretreatment improved endothelium-dependent vasodilation impaired by different concentrations of palmitic acid. • The inhibition of proliferation in endothelial cells by palmitic acid were inverted by fenofibric

  3. Endoplasmic reticulum stress involved in high-fat diet and palmitic acid-induced vascular damages and fenofibrate intervention

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yunxia, E-mail: wwwdluyx@sina.com [Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, Anhui 230032 (China); The Comprehensive Laboratory, Anhui Medical University, Hefei, Anhui 230032 (China); Cheng, Jingjing [Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, Anhui 230032 (China); Chen, Li [Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, Anhui 230032 (China); Department of Medical Laboratory, Anhui Provincial Hospital, Hefei, Anhui 230001 (China); Li, Chaofei; Chen, Guanjun [Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, Anhui 230032 (China); Gui, Li [The Comprehensive Laboratory, Anhui Medical University, Hefei, Anhui 230032 (China); Shen, Bing [Department of Physiology, Anhui Medical University, Hefei, Anhui 230032 (China); Zhang, Qiu [Department of Endocrinology, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230022 (China)

    2015-02-27

    Fenofibrate (FF) is widely used to lower blood lipids in clinical practice, but whether its protective effect on endothelium-dependent vasodilatation (EDV) in thoracic aorta is related with endoplasmic reticulum (ER) stress remains unknown. In this study, female Sprauge Dawley rats were divided into standard chow diets (SCD), high-fat diets (HFD) and HFD plus FF treatment group (HFD + FF) randomly. The rats of latter two groups were given HFD feeding for 5 months, then HFD + FF rats were treated with FF (30 mg/kg, once daily) via gavage for another 2 months. The pathological and tensional changes, protein expression of eNOS, and ER stress related genes in thoracic aorta were measured. Then impacts of palmitic acid (PA) and FF on EDV of thoracic aorta from normal female SD rats were observed. Ultimately the expression of ER stress related genes were assessed in primary mouse aortic endothelial cells (MAEC) treated by fenofibric acid (FA) and PA. We found that FF treatment improved serum lipid levels and pathological changes in thoracic aorta, accompanied with decreased ER stress and increased phosphorylation of eNOS. FF pretreatment also improved EDV impaired by different concentrations of PA treatment. The dose- and time-dependent inhibition of cell proliferation by PA were inverted by FA pretreatment. Phosphorylation of eNOS and expression of ER stress related genes were all inverted by FA pretreatment in PA-treated MAEC. Our findings show that fenofibrate recovers damaged EDV by chronic HFD feeding and acute stimulation of PA, this effect is related with decreased ER stress and increased phosphorylation of eNOS. - Highlights: • Fenofibrate treatment improved pathological changes in thoracic aorta by chronic high-fat-diet feeding. • Fenofibrate pretreatment improved endothelium-dependent vasodilation impaired by different concentrations of palmitic acid. • The inhibition of proliferation in endothelial cells by palmitic acid were inverted by fenofibric

  4. Substrate channeling: alpha-ketobutyrate inhibition of acetohydroxy acid synthase in Salmonella typhimurium.

    OpenAIRE

    Shaw, K J; Berg, C M

    1980-01-01

    Excess alpha-ketobutyrate inhibited the growth of Salmonella typhimurium LT2 by inhibiting the acetohydroxy acid synthase-catalyzed synthesis of alpha-acetolactate (a valine precursor). As a result, cells were starved for valine, and both ilvB (encoding acetohydroxy acid synthase I) and ilvGEDA (ilvG encodes acetohydroxy acid synthase II) were derepressed. The addition of valine reversed the effects of alpha-ketobutyrate.

  5. Myeloperoxidase Deletion Prevents High-Fat Diet–Induced Obesity and Insulin Resistance

    OpenAIRE

    Wang, Qilong; Xie, Zhonglin; Zhang, Wencheng; Zhou, Jun; Wu, Yue; Zhang, Miao; Zhu, Huaiping; Zou, Ming-Hui

    2014-01-01

    Activation of myeloperoxidase (MPO), a heme protein primarily expressed in granules of neutrophils, is associated with the development of obesity. However, whether MPO mediates high-fat diet (HFD)-induced obesity and obesity-associated insulin resistance remains to be determined. Here, we found that consumption of an HFD resulted in neutrophil infiltration and enhanced MPO expression and activity in epididymal white adipose tissue, with an increase in body weight gain and impaired insulin sig...

  6. Krill Oil Ameliorates Mitochondrial Dysfunctions in Rats Treated with High-Fat Diet

    OpenAIRE

    Alessandra Ferramosca; Annalea Conte; Vincenzo Zara

    2015-01-01

    In recent years, several studies focused their attention on the role of dietary fats in the pathogenesis of hepatic steatosis. It has been demonstrated that a high-fat diet is able to induce hyperglycemia, hyperinsulinemia, obesity, and nonalcoholic fatty liver disease. On the other hand, krill oil, a novel dietary supplement of n-3 PUFAs, has the ability to improve lipid and glucose metabolism, exerting possible protective effects against hepatic steatosis. In this study we have investigated...

  7. A Krill Oil Supplemented Diet Suppresses Hepatic Steatosis in High-Fat Fed Rats

    OpenAIRE

    Ferramosca, Alessandra; Conte, Annalea; Burri, Lena; Berge, Kjetil; De Nuccio, Francesco; Giudetti, Anna Maria; Zara, Vincenzo

    2012-01-01

    Krill oil (KO) is a dietary source of n-3 polyunsaturated fatty acids, mainly represented by eicosapentaenoic acid and docosahexaenoic acid bound to phospholipids. The supplementation of a high-fat diet with 2.5% KO efficiently prevented triglyceride and cholesterol accumulation in liver of treated rats. This effect was accompanied by a parallel reduction of the plasma levels of triglycerides and glucose and by the prevention of a plasma insulin increase. The investigation of the molecular me...

  8. Piperine potentiates the hypocholesterolemic effect of curcumin in rats fed on a high fat diet

    OpenAIRE

    TU, YAOSHENG; Sun, Dongmei; Zeng, Xiaohui; Yao, Nan; HUANG, XUEJUN; Huang, Dane; Chen, Yuxing

    2014-01-01

    It has previously been demonstrated that curcumin possesses a hypocholesterolemic effect and potentiates numerous pharmacological effects of curcumin, however, the mechanisms underlying this hypocholesterolemic effect and the interaction between curcumin and piperine remain to be elucidated. In the present study, male Sprague-Dawley rats were fed on a high-fat diet (HFD) to establish a hyperlipidemia (HLP) model. Co-administration of curcumin plus piperine was found to decrease the levels of ...

  9. Maternal Deprivation Exacerbates the Response to a High Fat Diet in a Sexually Dimorphic Manner

    Science.gov (United States)

    Mela, Virginia; Llorente-Berzal, Álvaro; Díaz, Francisca; Argente, Jesús; Viveros, María-Paz; Chowen, Julie A.

    2012-01-01

    Maternal deprivation (MD) during neonatal life has diverse long-term effects, including affectation of metabolism. Indeed, MD for 24 hours during the neonatal period reduces body weight throughout life when the animals are maintained on a normal diet. However, little information is available regarding how this early stress affects the response to increased metabolic challenges during postnatal life. We hypothesized that MD modifies the response to a high fat diet (HFD) and that this response differs between males and females. To address this question, both male and female Wistar rats were maternally deprived for 24 hours starting on the morning of postnatal day (PND) 9. Upon weaning on PND22 half of each group received a control diet (CD) and the other half HFD. MD rats of both sexes had significantly reduced accumulated food intake and weight gain compared to controls when raised on the CD. In contrast, when maintained on a HFD energy intake and weight gain did not differ between control and MD rats of either sex. However, high fat intake induced hyperleptinemia in MD rats as early as PND35, but not until PND85 in control males and control females did not become hyperleptinemic on the HFD even at PND102. High fat intake stimulated hypothalamic inflammatory markers in both male and female rats that had been exposed to MD, but not in controls. Reduced insulin sensitivity was observed only in MD males on the HFD. These results indicate that MD modifies the metabolic response to HFD intake, with this response being different between males and females. Thus, the development of obesity and secondary complications in response to high fat intake depends on numerous factors. PMID:23145019

  10. Resveratrol potentiates rapamycin to prevent hyperinsulinemia and obesity in male mice on high fat diet

    OpenAIRE

    Leontieva, O V; Paszkiewicz, G; Demidenko, Z N; Blagosklonny, M V

    2013-01-01

    High doses of rapamycin, an antiaging agent, can prevent obesity in mice on high fat diet (HFD). Obesity is usually associated with hyperinsulinemia. Here, we showed that rapamycin given orally, at doses that did not affect weight gain in male mice on HFD, tended to decrease fasting insulin levels. Addition of resveratrol, which alone did not affect insulin levels, potentiated the effect of rapamycin, so that the combination decreased obesity and prevented hyperinsulinemia. Neither rapamycin ...

  11. Carnitine Palmitoyltransferase 1b Deficient Mice Develop Severe Insulin Resistance After Prolonged High Fat Diet Feeding

    OpenAIRE

    Kim, Teayoun; Moore, John F.; Sharer, Jon D.; Yang, Kevin; Wood, Philip A.; Yang, Qinglin

    2014-01-01

    Background Carnitine palmitoyltransferase 1 (CPT1) is the rate-limiting enzyme governing the entry of long-chain acyl-CoAs into mitochondria. Treatments with CPT1 inhibitors protect against insulin resistance in short-term preclinical animal studies. We recently reported that mice with muscle isoform CPT1b deficiency demonstrated improved insulin sensitivity when fed a High Fat-Diet (HFD) for up to 5 months. In this follow up study, we further investigated whether the insulin sensitizing effe...

  12. Chronic unpredictable mild stress combined with a high-fat diets aggravates atherosclerosis in rats

    OpenAIRE

    Wang, Shuling; Xiaoling, Gao; Pingting, Li; Shuqiang, Liu; Yuaner, Zeng

    2014-01-01

    Background Depression and high-fat diet are both known as independent risk factors for atherosclerosis and other cardiovascular diseases, suggesting the interaction of psychological and physiological factors in the development of these diseases. The liver is a crucial organ that facilitate lipid metabolism especially in reverse cholesterol transport (RCT), while according to the theory of Traditional Chinese Medicine, depression as a kind of psychological stress has an influence on hepatic fu...

  13. Voluntary Exercise Improves High-Fat Diet-Induced Leptin Resistance Independent of Adiposity

    OpenAIRE

    Carhuatanta, Kimberly A. Krawczewski; Demuro, Giovanna; Tschöp, Matthias H.; Pfluger, Paul T.; Benoit, Stephen C.; Obici, Silvana

    2011-01-01

    The efficacy of exercise as primary prevention of obesity is the subject of intense investigation. Here, we show that voluntary exercise in a mouse strain susceptible to diet-induced obesity (C57B6J) decreases fat mass and increases energy expenditure. In addition, exercise attenuates obesity in mice fed a high-fat diet (HFD). Using FosB immunoreactivity as a marker of chronic neuronal activation, we found that exercise activates leptin receptor-positive neurons in the ventromedial hypothalam...

  14. Neurodegeneration in an animal model of Parkinson's disease is exacerbated by a high-fat diet

    OpenAIRE

    Morris, Jill K.; Bomhoff, Gregory L.; Stanford, John A.; Geiger, Paige C.

    2010-01-01

    Despite numerous clinical studies supporting a link between type 2 diabetes (T2D) and Parkinson's disease (PD), the clinical literature remains equivocal. We, therefore, sought to address the relationship between insulin resistance and nigrostriatal dopamine (DA) in a preclinical animal model. High-fat feeding in rodents is an established model of insulin resistance, characterized by increased adiposity, systemic oxidative stress, and hyperglycemia. We subjected rats to a normal chow or high-...

  15. Decreased adipose tissue zinc content is associated with metabolic parameters in high fat fed Wistar rats

    Directory of Open Access Journals (Sweden)

    Alexey A. Tinkov

    2016-03-01

    Full Text Available Background. Limited data on adipose tissue zinc content in obesity exist. At the same time, the association between adipose tissue zinc content and metabolic parameters in dietary-induced obesity is poorly studied. Therefore, the primary objective of this study is to assess adipose tissue zinc content and its association  with morphometric parameters, adipokine spectrum, proinflammatory cytokines, and apolipoprotein profile in high fat fed Wistar rats. Material and methods. A total of 48 adult female Wistar rats were used in the present study. Rats were fed either control (10% of fat or high fat diet (31.6% of fat. Adipose tissue zinc content was assessed using inductively coupled plasma mass spectrometry. Rats’ serum was examined for adiponectin, leptin, insulin, interleukin-6, and tumor necrosis factor-α using enzyme-linked immunosorbent assay kits. Serum glucose and apolipoprotein spectrum were also evaluated. Results. High fat feeding resulted in a significant 34% decrease in adipose tissue zinc content in comparison to the control values. Fat pad zinc levels were significantly inversely associated with morphometric param- eters, circulating leptin, insulin, tumor necrosis factor-α levels and HOMA-IR values. At the same time,      a significant correlation with apolipoprotein A1 concentration was observed. Conclusion. Generally, the obtained data indicate that (1 high fat feeding results in decreased adipose tis- sue zinc content; (2 adipose tissue zinc content is tightly associated with excessive adiposity, inflammation, insulin resistance and potentially atherogenic changes.

  16. Design of a Microstructured System for Homogenization of Dairy Products with High Fat Content

    OpenAIRE

    Köhler, K; Aguilar, F.; Hensel, A.; Schubert, K; Schubert, H.; H.P. Schuchmann

    2008-01-01

    High pressure homogenization of dairy products is today state of the art but limited by the fat content (max 17 vol.-%). This article describes the development of a novel simultaneous homogenization and mixing (SHM) valve which allows homogenization of dairy products with a fat content of up to 42 vol.-%. The challenging task of homogenizing dairy products with high fat content is to stabilize disrupted fat droplets especially against extensive aggregation. Aggregation and coalescence rates c...

  17. Modulation of PPAR Expression and Activity in Response to Polyphenolic Compounds in High Fat Diets

    OpenAIRE

    J. Abraham Domínguez-Avila; Gustavo A. González-Aguilar; Emilio Alvarez-Parrilla; de la Rosa, Laura A.

    2016-01-01

    Peroxisome proliferator-activated receptors (PPAR) are transcription factors that modulate energy metabolism in liver, adipose tissue and muscle. High fat diets (HFD) can negatively impact PPAR expression or activity, favoring obesity, dyslipidemia, insulin resistance and other conditions. However, polyphenols (PP) found in vegetable foodstuffs are capable of positively modulating this pathway. We therefore focused this review on the possible effects that PP can have on PPAR when administered...

  18. High Fat, Low Carbohydrate Diet Limit Fear and Aggression in Göttingen Minipigs

    OpenAIRE

    Annika Maria Juul Haagensen; Dorte Bratbo Sørensen; Peter Sandøe; Lindsay R Matthews; Malene Muusfeldt Birck; Johannes Josef Fels; Arne Astrup

    2014-01-01

    High fat, low carbohydrate diets have become popular, as short-term studies show that such diets are effective for reducing body weight, and lowering the risk of diabetes and cardiovascular disease. There is growing evidence from both humans and other animals that diet affects behaviour and intake of fat has been linked, positively and negatively, with traits such as exploration, social interaction, anxiety and fear. Animal models with high translational value can help provide relevant and im...

  19. High fat diet subverts hepatocellular iron uptake determining dysmetabolic iron overload

    OpenAIRE

    Paola Dongiovanni; Claudia Lanti; Stefano Gatti; Raffaela Rametta; Stefania Recalcati; Marco Maggioni; Anna Ludovica Fracanzani; Patrizia Riso; Gaetano Cairo; Silvia Fargion; Luca Valenti

    2015-01-01

    Increased serum ferritin associated with mild hepatic iron accumulation, despite preserved upregulation of the iron hormone hepcidin, is frequently observed in patients with dysmetabolic overload syndrome (DIOS). Genetic factors and Western diet represent predisposing conditions, but the mechanisms favoring iron accumulation in DIOS are still unclear. Aims of this study were to assess the effect a high-fat diet (HFD) on hepatic iron metabolism in an experimental model in rats, to further char...

  20. Spatial cognition in adult and aged mice exposed to high-fat diet

    OpenAIRE

    Kesby, JP; Kim, JJ; M. Scadeng; Woods, G.; Kado, DM; Olefsky, JM; Jeste, DV; Achim, CL; Semenova, S

    2015-01-01

    © 2015 Kesby et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Aging is associated with a decline in multiple aspects of cognitive function, with spatial cognition being particularly sensitive to age-related decline. Environmental stressors, such as high-fat diet (HFD) exposure, that produce a diabetic ...

  1. Inflammatory and metabolic responses to high-fat meals with and without dairy products in men.

    Science.gov (United States)

    Schmid, Alexandra; Petry, Nicolai; Walther, Barbara; Bütikofer, Ueli; Luginbühl, Werner; Gille, Doreen; Chollet, Magali; McTernan, Philip G; Gijs, Martin A M; Vionnet, Nathalie; Pralong, François P; Laederach, Kurt; Vergères, Guy

    2015-06-28

    Postprandial inflammation is an important factor for human health since chronic low-grade inflammation is associated with chronic diseases. Dairy products have a weak but significant anti-inflammatory effect on postprandial inflammation. The objective of the present study was to compare the effect of a high-fat dairy meal (HFD meal), a high-fat non-dairy meal supplemented with milk (HFM meal) and a high-fat non-dairy control meal (HFC meal) on postprandial inflammatory and metabolic responses in healthy men. A cross-over study was conducted in nineteen male subjects. Blood samples were collected before and 1, 2, 4 and 6 h after consumption of the test meals. Plasma concentrations of insulin, glucose, total cholesterol, LDL-cholesterol, HDL-cholesterol, TAG and C-reactive protein (CRP) were measured at each time point. IL-6, TNF-α and endotoxin concentrations were assessed at baseline and endpoint (6 h). Time-dependent curves of these metabolic parameters were plotted, and the net incremental AUC were found to be significantly higher for TAG and lower for CRP after consumption of the HFM meal compared with the HFD meal; however, the HFM and HFD meals were not different from the HFC meal. Alterations in IL-6, TNF-α and endotoxin concentrations were not significantly different between the test meals. The results suggest that full-fat milk and dairy products (cheese and butter) have no significant impact on the inflammatory response to a high-fat meal. PMID:25990454

  2. Protective effects of Arctium lappa L. root extracts (AREs) on high fat diet induced quail atherosclerosis

    OpenAIRE

    Wang, Zhi; Li, Ping; Wang, Chenjing; Jiang, Qixiao; Zhang, Lei; Cao, Yu; Zhong, Weizhen; Wang, Chunbo

    2016-01-01

    Background This study was designed to evaluate the protective effects of Arctium lappa L. root extracts (AREs) from different extraction methods (aqueous, ethanol, chloroform and flavone) on atherosclerosis. Methods Quails (Coturnix coturnix) were subjected to high fat diet, with or without one of the four different AREs or positive control simvastatin. Blood samples were collected before treatment, after 4.5 weeks or ten weeks to assess lipid profile (Levels of total cholesterol (TC), Triacy...

  3. Quantitative Proteomic and Functional Analysis of Liver Mitochondria from High Fat Diet (HFD) Diabetic Mice*

    OpenAIRE

    Guo, Yurong; Darshi, Manjula; Ma, Yuliang; Perkins, Guy A.; Shen, Zhouxin; Haushalter, Kristofer J.; Saito, Rintaro; Chen, Ai; Lee, Yun Sok; Patel, Hemal H.; Briggs, Steven P.; Ellisman, Mark H.; Jerrold M Olefsky; Susan S Taylor

    2013-01-01

    Insulin resistance plays a major role in the development of type 2 diabetes and obesity and affects a number of biological processes such as mitochondrial biogenesis. Though mitochondrial dysfunction has been linked to the development of insulin resistance and pathogenesis of type 2 diabetes, the precise mechanism linking the two is not well understood. We used high fat diet (HFD)-induced obesity dependent diabetes mouse models to gain insight into the potential pathways altered with metaboli...

  4. Pharmacological Inhibition of Voltage-gated Ca2+ Channels for Chronic Pain Relief

    OpenAIRE

    Lee, Seungkyu

    2013-01-01

    Chronic pain is a major therapeutic problem as the current treatment options are unsatisfactory with low efficacy and deleterious side effects. Voltage-gated Ca2+ channels (VGCCs), which are multi-complex proteins consisting of α1, β, γ, and α2δ subunits, play an important role in pain signaling. These channels are involved in neurogenic inflammation, excitability, and neurotransmitter release in nociceptors. It has been previously shown that N-type VGCCs (Cav2.2) are a major pain target. U.S...

  5. Hesperidin ameliorates streptozotocin and high fat diet induced diabetic nephropathy in rats

    Directory of Open Access Journals (Sweden)

    Dilpesh P. Jain

    2014-12-01

    Full Text Available Objective: The present study investigates protective effect of hesperidin on streptozotocin and high fat diet induced diabetic nephropathy in experimental type 2 diabetic rats. Methods: Sprague Dawley rats were fed with high fat emulsion and high fat diet for 2 weeks to induce glucose intolerance and then injected with streptozotocin (35 mg/kg, i.p.. Following 48 h of streptozotocin injection blood glucose level was estimated to confirm hyperglycemia. After 4 weeks of diabetes induction diabetic rats were orally treated with hesperidin (50, 100 and 200 mg/kg body weight for 4 weeks. At the end of the treatment kidney functions, oxidative stress indices, biochemical estimations and histopathological examination were carried out to assess the efficacy of the treatment. Results: Diabetic rats exhibited significant rise in blood glucose level, altered kidney functions, oxidative stress and histological abnormalities compared to control rats. Hesperidin treatment significantly reduced the elevated levels of blood glucose, creatinine, urea nitrogen, total cholesterol and triglyceride when compared with diabetic control rats. Significant rise in renal hypertrophy, hyperfiltration, microalbuminuria as well as oxidative stress in the diabetic rats were effectively attenuated with hesperidin treatment, dose dependently. Moreover, basement membrane thickening and mesangial expansion observed in the kidney of diabetic rats restored near to normal structure. Conclusion: Results of the present study suggest that hesperidin ameliorate early diabetic nephropathy. [J Exp Integr Med 2014; 4(4.000: 261-267

  6. High-fat Diet Promotes Cardiac Remodeling in an Experimental Model of Obesity

    Directory of Open Access Journals (Sweden)

    Fernando Martins

    2015-01-01

    Full Text Available AbstractBackground:Although nutritional, metabolic and cardiovascular abnormalities are commonly seen in experimental studies of obesity, it is uncertain whether these effects result from the treatment or from body adiposity.Objective:To evaluate the influence of treatment and body composition on metabolic and cardiovascular aspects in rats receiving high saturated fat diet.Methods:Sixteen Wistar rats were used, distributed into two groups, the control (C group, treated with isocaloric diet (2.93 kcal/g and an obese (OB group, treated with high-fat diet (3.64 kcal/g. The study period was 20 weeks. Analyses of nutritional behavior, body composition, glycemia, cholesterolemia, lipemia, systolic arterial pressure, echocardiography, and cardiac histology were performed.Results:High-fat diet associates with manifestations of obesity, accompanied by changes in glycemia, cardiomyocyte hypertrophy, and myocardial interstitial fibrosis. After adjusting for adiposity, the metabolic effects were normalized, whereas differences in morphometric changes between groups were maintained.Conclusion:It was concluded that adiposity body composition has a stronger association with metabolic disturbances in obese rodents, whereas the high-fat dietary intervention is found to be more related to cardiac morphological changes in experimental models of diet-induced obesity.

  7. Lessons from Mouse Models of High-Fat Diet-Induced NAFLD

    Directory of Open Access Journals (Sweden)

    Yasuo Terauchi

    2013-10-01

    Full Text Available Nonalcoholic fatty liver disease (NAFLD encompasses a clinicopathologic spectrum of diseases ranging from isolated hepatic steatosis to nonalcoholic steatohepatitis (NASH, the more aggressive form of fatty liver disease that may progress to cirrhosis and cirrhosis-related complications, including hepatocellular carcinoma. The prevalence of NAFLD, including NASH, is also increasing in parallel with the growing epidemics of obesity and diabetes. However, the causal relationships between obesity and/or diabetes and NASH or liver tumorigenesis have not yet been clearly elucidated. Animal models of NAFLD/NASH provide crucial information, not only for elucidating the pathogenesis of NAFLD/NASH, but also for examining therapeutic effects of various agents. A high-fat diet is widely used to produce hepatic steatosis and NASH in experimental animals. Several studies, including our own, have shown that long-term high-fat diet loading, which can induce obesity and insulin resistance, can also induce NASH and liver tumorigenesis in C57BL/6J mice. In this article, we discuss the pathophysiology of and treatment strategies for NAFLD and subsequent NAFLD-related complications such as NASH and liver tumorigenesis, mainly based on lessons learned from mouse models of high-fat diet-induced NAFLD/NASH.

  8. Effect of High-Fat Diet upon Inflammatory Markers and Aortic Stiffening in Mice

    Directory of Open Access Journals (Sweden)

    Andre Bento Chaves Santana

    2014-01-01

    Full Text Available Changes in lifestyle such as increase in high-fat food consumption are an important cause for vascular diseases. The present study aimed to investigate the involvement of ACE and TGF-β in the aorta stiffness induced by high-fat diet. C57BL/6 male mice were divided in two groups according to their diet for 8 weeks: standard diet (ST and high-fat diet (HF. At the end of the protocol, body weight gain, adipose tissue content, serum lipids and glucose levels, and aorta morphometric and biochemical measurements were performed. Analysis of collagen fibers by picrosirius staining of aorta slices showed that HF diet promoted increase of thin (55% and thick (100% collagen fibers deposition and concomitant disorganization of these fibers orientations in the aorta vascular wall (50%. To unravel the mechanism involved, myeloperoxidase (MPO and angiotensin I converting enzyme (ACE were evaluated by protein expression and enzyme activity. HF diet increased MPO (90% and ACE (28% activities, as well as protein expression of ACE. TGF-β was also increased in aorta tissue of HF diet mice after 8 weeks. Altogether, we have observed that the HF diet-induced aortic stiffening may be associated with increased oxidative stress damage and activation of the RAS in vascular tissue.

  9. High-Fat Diet Causes Subfertility and Compromised Ovarian Function Independent of Obesity in Mice.

    Science.gov (United States)

    Skaznik-Wikiel, Malgorzata E; Swindle, Delaney C; Allshouse, Amanda A; Polotsky, Alex J; McManaman, James L

    2016-05-01

    Excess calorie consumption, particularly of a diet high in fat, is a risk factor for both obesity and reproductive disorders. Animal model studies indicate that elevated dietary fat can influence some reproductive functions independent of obesity. In the current study we sought to determine whether a high-fat diet (HFD) impacts ovarian function, long-term fertility, and local and systemic markers of inflammation independent of obesity. Five-week-old mice were fed either low-fat diet (control group-LF-Ln) or HFD for 10 wk and were divided based on body weight into high-fat obese (HF-Ob: >25 g) and high-fat lean (HF-Ln: obesity phenotype. Macrophage counts revealed increased tissue inflammation in the ovary independent of obesity. In addition, serum proinflammatory cytokines were increased in HF-Ln and HF-Ob in comparison to LF-Ln mice. Moreover, HFD had a sustained effect on litter production rate and number of pups per litter regardless of obese phenotype. This study describes for the first time that exposure to HFD causes significant reduction in primordial follicles, compromised fertility, produced higher proinflammatory cytokine levels, and increased ovarian macrophage infiltration, independent of obesity. The negative effects of HFD on primordial follicles may be mediated by increased tissue inflammation. PMID:27030045

  10. ACE Reduces Metabolic Abnormalities in a High-Fat Diet Mouse Model

    Directory of Open Access Journals (Sweden)

    Seong-Jong Lee

    2015-01-01

    Full Text Available The medicinal plants Artemisia iwayomogi (A. iwayomogi and Curcuma longa (C. longa radix have been used to treat metabolic abnormalities in traditional Korean medicine and traditional Chinese medicine (TKM and TCM. In this study we evaluated the effect of the water extract of a mixture of A. iwayomogi and C. longa (ACE on high-fat diet-induced metabolic syndrome in a mouse model. Four groups of C57BL/6N male mice (except for the naive group were fed a high-fat diet freely for 10 weeks. Among these, three groups (except the control group were administered a high-fat diet supplemented with ACE (100 or 200 mg/kg or curcumin (50 mg/kg. Body weight, accumulation of adipose tissues in abdomen and size of adipocytes, serum lipid profiles, hepatic steatosis, and oxidative stress markers were analyzed. ACE significantly reduced the body and peritoneal adipose tissue weights, serum lipid profiles (total cholesterol and triglycerides, glucose levels, hepatic lipid accumulation, and oxidative stress markers. ACE normalized lipid synthesis-associated gene expressions (peroxisome proliferator-activated receptor gamma, PPARγ; fatty acid synthase, FAS; sterol regulatory element-binding transcription factor-1c, SREBP-1c; and peroxisome proliferator-activated receptor alpha, PPARα. The results from this study suggest that ACE has the pharmaceutical potential reducing the metabolic abnormalities in an animal model.

  11. Adipose tissue chromium and vanadium disbalance in high-fat fed Wistar rats.

    Science.gov (United States)

    Tinkov, Alexey A; Popova, Elizaveta V; Polyakova, Valentina S; Kwan, Olga V; Skalny, Anatoly V; Nikonorov, Alexandr A

    2015-01-01

    The primary objective of the current study is to investigate the relationship between adipose tissue chromium and vanadium content and adipose tissue dysfunction in a model of diet-induced obesity. A total of 26 female Wistar rats were fed either standard or high-fat diet (31.6% of fat from total caloric content) for 3 months. High-fat-feeding resulted in 21 and 33% decrease in adipose tissue chromium and vanadium content, respectively. No change was seen in hair chromium or vanadium levels. Statistical analysis revealed a significant inverse correlation of adipose tissue Cr and V with animal morphometric parameters and adipocyte size. Significant inverse dependence was observed between adipose tissue Cr and V and serum leptin and proinflammatory cytokines' levels. At the same time, adipose tissue Cr and V levels were characterized by positive correlation between serum adiponectin and adiponectin/leptin ratio. Adipose tissue Cr and V were inversely correlated (prats; however, both serum glucose and HOMA-IR levels were significantly higher in high-fat fed, compared to control, rats. The results allow to hypothesize that impairment of adipose tissue Cr and V content plays a certain role in the development of adipose tissue endocrine dysfunction in obesity. PMID:25194956

  12. ACE Reduces Metabolic Abnormalities in a High-Fat Diet Mouse Model

    Science.gov (United States)

    Lee, Seong-Jong; Han, Jong-Min; Lee, Jin-Seok; Son, Chang-Gue; Im, Hwi-Jin; Jo, Hyun-Kyung; Yoo, Ho-Ryong; Kim, Yoon-Sik; Seol, In-Chan

    2015-01-01

    The medicinal plants Artemisia iwayomogi (A. iwayomogi) and Curcuma longa (C. longa) radix have been used to treat metabolic abnormalities in traditional Korean medicine and traditional Chinese medicine (TKM and TCM). In this study we evaluated the effect of the water extract of a mixture of A. iwayomogi and C. longa (ACE) on high-fat diet-induced metabolic syndrome in a mouse model. Four groups of C57BL/6N male mice (except for the naive group) were fed a high-fat diet freely for 10 weeks. Among these, three groups (except the control group) were administered a high-fat diet supplemented with ACE (100 or 200 mg/kg) or curcumin (50 mg/kg). Body weight, accumulation of adipose tissues in abdomen and size of adipocytes, serum lipid profiles, hepatic steatosis, and oxidative stress markers were analyzed. ACE significantly reduced the body and peritoneal adipose tissue weights, serum lipid profiles (total cholesterol and triglycerides), glucose levels, hepatic lipid accumulation, and oxidative stress markers. ACE normalized lipid synthesis-associated gene expressions (peroxisome proliferator-activated receptor gamma, PPARγ; fatty acid synthase, FAS; sterol regulatory element-binding transcription factor-1c, SREBP-1c; and peroxisome proliferator-activated receptor alpha, PPARα). The results from this study suggest that ACE has the pharmaceutical potential reducing the metabolic abnormalities in an animal model. PMID:26508977

  13. The Kunitz-Type Protein ShPI-1 Inhibits Serine Proteases and Voltage-Gated Potassium Channels.

    Science.gov (United States)

    García-Fernández, Rossana; Peigneur, Steve; Pons, Tirso; Alvarez, Carlos; González, Lidice; Chávez, María A; Tytgat, Jan

    2016-01-01

    The bovine pancreatic trypsin inhibitor (BPTI)-Kunitz-type protein ShPI-1 (UniProt: P31713) is the major protease inhibitor from the sea anemone Stichodactyla helianthus. This molecule is used in biotechnology and has biomedical potential related to its anti-parasitic effect. A pseudo wild-type variant, rShPI-1A, with additional residues at the N- and C-terminal, has a similar three-dimensional structure and comparable trypsin inhibition strength. Further insights into the structure-function relationship of rShPI-1A are required in order to obtain a better understanding of the mechanism of action of this sea anemone peptide. Using enzyme kinetics, we now investigated its activity against other serine proteases. Considering previous reports of bifunctional Kunitz-type proteins from anemones, we also studied the effect of rShPI-1A on voltage-gated potassium (Kv) channels. rShPI-1A binds Kv1.1, Kv1.2, and Kv1.6 channels with IC50 values in the nM range. Hence, ShPI-1 is the first member of the sea anemone type 2 potassium channel toxins family with tight-binding potency against several proteases and different Kv1 channels. In depth sequence analysis and structural comparison of ShPI-1 with similar protease inhibitors and Kv channel toxins showed apparent non-sequence conservation for known key residues. However, we detected two subtle patterns of coordinated amino acid substitutions flanking the conserved cysteine residues at the N- and C-terminal ends. PMID:27089366

  14. The Kunitz-Type Protein ShPI-1 Inhibits Serine Proteases and Voltage-Gated Potassium Channels

    Science.gov (United States)

    García-Fernández, Rossana; Peigneur, Steve; Pons, Tirso; Alvarez, Carlos; González, Lidice; Chávez, María A.; Tytgat, Jan

    2016-01-01

    The bovine pancreatic trypsin inhibitor (BPTI)-Kunitz-type protein ShPI-1 (UniProt: P31713) is the major protease inhibitor from the sea anemone Stichodactyla helianthus. This molecule is used in biotechnology and has biomedical potential related to its anti-parasitic effect. A pseudo wild-type variant, rShPI-1A, with additional residues at the N- and C-terminal, has a similar three-dimensional structure and comparable trypsin inhibition strength. Further insights into the structure-function relationship of rShPI-1A are required in order to obtain a better understanding of the mechanism of action of this sea anemone peptide. Using enzyme kinetics, we now investigated its activity against other serine proteases. Considering previous reports of bifunctional Kunitz-type proteins from anemones, we also studied the effect of rShPI-1A on voltage-gated potassium (Kv) channels. rShPI-1A binds Kv1.1, Kv1.2, and Kv1.6 channels with IC50 values in the nM range. Hence, ShPI-1 is the first member of the sea anemone type 2 potassium channel toxins family with tight-binding potency against several proteases and different Kv1 channels. In depth sequence analysis and structural comparison of ShPI-1 with similar protease inhibitors and Kv channel toxins showed apparent non-sequence conservation for known key residues. However, we detected two subtle patterns of coordinated amino acid substitutions flanking the conserved cysteine residues at the N- and C-terminal ends. PMID:27089366

  15. Inhibition of collagen synthesis by select calcium and sodium channel blockers can be mitigated by ascorbic acid and ascorbyl palmitate.

    Science.gov (United States)

    Ivanov, Vadim; Ivanova, Svetlana; Kalinovsky, Tatiana; Niedzwiecki, Aleksandra; Rath, Matthias

    2016-01-01

    muscle cells, assayed by measuring intracellular collagen content. We observed increased intracellular levels of ascorbate under supplementation with elevated doses of ascorbic acid, as well as its lipid soluble derivative ascorbyl palmitate. Nifedipine reduced ascorbic acid intracellular influx in cultured aortic smooth muscle cells with nifedipine (50 µM) compared to control. Adverse effects of nifedipine were neutralized either by an increased level of cell supplementation with ascorbic acid or by substituting it with ascorbyl palmitate. These studies suggest that adverse effects of channel blockers could be caused by their weakening the arterial wall integrity by interfering with proper extracellular matrix formation. In conclusion, these studies confirm the adverse effects of channel blockers on collagen type l and lV deposition, the key ECM components essential for maintaining optimal structural integrity of the arterial walls. Ascorbate supplementation reversed channel blocker inhibition of these collagen types synthesis and deposition. The results of this study imply the benefits of ascorbate and ascorbate palmitate supplementation in medical management of cardiovascular disease in order to compensate for adverse effects of channel blockers. PMID:27335688

  16. Inhibition of collagen synthesis by select calcium and sodium channel blockers can be mitigated by ascorbic acid and ascorbyl palmitate

    Science.gov (United States)

    Ivanov, Vadim; Ivanova, Svetlana; Kalinovsky, Tatiana; Niedzwiecki, Aleksandra; Rath, Matthias

    2016-01-01

    muscle cells, assayed by measuring intracellular collagen content. We observed increased intracellular levels of ascorbate under supplementation with elevated doses of ascorbic acid, as well as its lipid soluble derivative ascorbyl palmitate. Nifedipine reduced ascorbic acid intracellular influx in cultured aortic smooth muscle cells with nifedipine (50 µM) compared to control. Adverse effects of nifedipine were neutralized either by an increased level of cell supplementation with ascorbic acid or by substituting it with ascorbyl palmitate. These studies suggest that adverse effects of channel blockers could be caused by their weakening the arterial wall integrity by interfering with proper extracellular matrix formation. In conclusion, these studies confirm the adverse effects of channel blockers on collagen type l and lV deposition, the key ECM components essential for maintaining optimal structural integrity of the arterial walls. Ascorbate supplementation reversed channel blocker inhibition of these collagen types synthesis and deposition. The results of this study imply the benefits of ascorbate and ascorbate palmitate supplementation in medical management of cardiovascular disease in order to compensate for adverse effects of channel blockers.

  17. Pre-clinical evolutionary study of Clerodendrum phlomidis as an anti-obesity agent against high fat diet induced C57BL/6J mice

    Institute of Scientific and Technical Information of China (English)

    Vijay R Chidrawar; Krishnakant N Patel; Havagiray R Chitme; Shruti S Shiromwar

    2012-01-01

    Objective: Anti-obesity activity of alcoholic and methanolic extracts of roots of Clerodendrumphlomidis was evaluated against high fat diet (HFD) induced obesity in C57BL/6J female mice. Methods: Obesity was induced by feeding high fat diet for 13 weeks to C57BL/6J female mice and one group was kept on normal chow diet in order to evaluate the effect of Clerodendrumphlomidis on food intake, body weight changes, digestive enzyme activity, lipid metabolism, theromogenesis, adiposities diameter and histology of fat pad. Results: Among these two extracts methanolic extract of Clerodendrum phlomidis (MECP) have shown strong anti-obesity effect compare to alcoholic extract of Clerodendrum phlomidis (AECP). LD50 value was found to be more than 2000 mg/kg. Conclusions: MECP have shown more promising effects than AECP may be because of its multiple mechanisms. Anti-obesity activity produced by MECP is because of inhibition of pancreatic lipase activity which delays the intestinal absorption of dietary fat. Inhibition of pancreatic lipase activity was confirmed by in-vitro studies. MECP also containsβ-sitosterol in abundant amount which was confirmed by HPTLC analysis. Moreover flavonoid content in the plant has anorexic property. By this study we concluded that MECP is beneficial for the suppression of obesity and associated complications like T2DM.

  18. Intracellular Na+ inhibits volume regulated anion channel in rat cortical astrocytes

    Czech Academy of Sciences Publication Activity Database

    Minieri, L.; Pivoňková, Helena; Harantová, Lenka; Anděrová, Miroslava; Ferroni, S.

    2015-01-01

    Roč. 132, č. 3 (2015), s. 286-300. ISSN 0022-3042 R&D Projects: GA ČR(CZ) GBP304/12/G069; GA ČR GA13-02154S Institutional support: RVO:68378041 Keywords : volume-regulated anion channels * intracellular sodium * cell volume Subject RIV: FH - Neurology Impact factor: 4.281, year: 2014

  19. Molecular basis for class Ib anti-arrhythmic inhibition of cardiac sodium channels

    DEFF Research Database (Denmark)

    Pless, Stephan Alexander; Galpin, Jason D; Frankel, Adam; Ahern, Christopher A

    2011-01-01

    Cardiac sodium channels are established therapeutic targets for the management of inherited and acquired arrhythmias by class I anti-arrhythmic drugs (AADs). These drugs share a common target receptor bearing two highly conserved aromatic side chains, and are subdivided by the Vaughan-Williams cl...

  20. Epoxyeicosatrienoic acid analogue lowers blood pressure through vasodilation and sodium channel inhibition

    Czech Academy of Sciences Publication Activity Database

    Khan, M. A. H.; Pavlov, T. S.; Christain, S. V.; Neckář, Jan; Staruschenko, A.; Gauthier, K. M.; Capdevila, J. H.; Falck, J. R.; Campbell, W. B.; Imig, J. D.

    2014-01-01

    Roč. 127, č. 7 (2014), s. 463-474. ISSN 0143-5221 Institutional support: RVO:67985823 Keywords : angiotensin II * epithelial sodium channel (ENaC) * epoxyeicosatrienoic acid analogue * hypertension Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 5.598, year: 2014

  1. An improved ivermectin-activated chloride channel receptor for inhibiting electrical activity in defined neuronal populations

    DEFF Research Database (Denmark)

    Lynagh, Timothy Peter; Lynch, Joseph W

    2010-01-01

    for surgically implanted stimulus delivery methods and their use of nonhuman receptors. A third silencing method, an invertebrate glutamate-gated chloride channel receptor (GluClR) activated by ivermectin, solves the stimulus delivery problem as ivermectin is a safe, well tolerated drug that reaches...

  2. BK K+ channel blockade inhibits radiation-induced migration/brain infiltration of glioblastoma cells.

    Science.gov (United States)

    Edalat, Lena; Stegen, Benjamin; Klumpp, Lukas; Haehl, Erik; Schilbach, Karin; Lukowski, Robert; Kühnle, Matthias; Bernhardt, Günther; Buschauer, Armin; Zips, Daniel; Ruth, Peter; Huber, Stephan M

    2016-03-22

    Infiltration of the brain by glioblastoma cells reportedly requires Ca2+ signals and BK K+ channels that program and drive glioblastoma cell migration, respectively. Ionizing radiation (IR) has been shown to induce expression of the chemokine SDF-1, to alter the Ca2+ signaling, and to stimulate cell migration of glioblastoma cells. Here, we quantified fractionated IR-induced migration/brain infiltration of human glioblastoma cells in vitro and in an orthotopic mouse model and analyzed the role of SDF-1/CXCR4 signaling and BK channels. To this end, the radiation-induced migratory phenotypes of human T98G and far-red fluorescent U-87MG-Katushka glioblastoma cells were characterized by mRNA and protein expression, fura-2 Ca2+ imaging, BK patch-clamp recording and transfilter migration assay. In addition, U-87MG-Katushka cells were grown to solid glioblastomas in the right hemispheres of immunocompromised mice, fractionated irradiated (6 MV photons) with 5 × 0 or 5 × 2 Gy, and SDF-1, CXCR4, and BK protein expression by the tumor as well as glioblastoma brain infiltration was analyzed in dependence on BK channel targeting by systemic paxilline application concomitant to IR. As a result, IR stimulated SDF-1 signaling and induced migration of glioblastoma cells in vitro and in vivo. Importantly, paxilline blocked IR-induced migration in vivo. Collectively, our data demonstrate that fractionated IR of glioblastoma stimulates and BK K+ channel targeting mitigates migration and brain infiltration of glioblastoma cells in vivo. This suggests that BK channel targeting might represent a novel approach to overcome radiation-induced spreading of malignant brain tumors during radiotherapy. PMID:26893360

  3. ZD7288, a selective hyperpolarization-activated cyclic nucleotide-gated channel blocker, inhibits hippocampal synaptic plasticity

    Institute of Scientific and Technical Information of China (English)

    Xiao-xue Zhang; Xiao-chun Min; Xu-lin Xu; Min Zheng; Lian-jun Guo

    2016-01-01

    The selective hyperpolarization-activated cyclic nucleotide-gated (HCN) channel blocker 4-(N-ethyl-N-phenylamino)-1,2-dimeth-yl-6-(methylamino) pyrimidinium chloride (ZD7288) blocks the induction of long-term potentiation in the perforant path–CA3 region in rat hippocampusin vivo. To explore the mechanisms underlying the action of ZD7288, we recorded excitatory postsynaptic potentials in perforant path–CA3 synapses in male Sprague-Dawley rats. We measured glutamate content in the hippocampus and in cultured hip-pocampal neurons using high performance liquid chromatography, and determined intracellular Ca2+ concentration ([Ca2+]i) using Fura-2. ZD7288 inhibited the induction and maintenance of long-term potentiation, and these effects were mirrored by the nonspeciifc HCN channel blocker cesium. ZD7288 also decreased glutamate release in hippocampal tissue and in cultured hippocampal neurons. Further-more, ZD7288 attenuated glutamate-induced rises in [Ca2+]i in a concentration-dependent manner and reversed 8-Br-cAMP-mediated facilitation of these glutamate-induced [Ca2+]i rises. Our results suggest that ZD7288 inhibits hippocampal synaptic plasticity both gluta-mate release and resultant [Ca2+]i increases in rat hippocampal neurons.

  4. The Inhibition by Oxaliplatin, a Platinum-Based Anti-Neoplastic Agent, of the Activity of Intermediate-Conductance Ca2+-Activated K+ Channels in Human Glioma Cells

    Directory of Open Access Journals (Sweden)

    Mei-Han Huang

    2015-10-01

    Full Text Available Oxaliplatin (OXAL is a third-generation organoplatinum which is effective against advanced cancer cells including glioma cells. How this agent and other related compounds interacts with ion channels in glioma cells is poorly understood. OXAL (100 µM suppressed the amplitude of whole-cell K+ currents (IK; and, either DCEBIO or ionomycin significantly reversed OXAL-mediated inhibition of IK in human 13-06-MG glioma cells. In OXAL-treated cells, TRAM-34 did not suppress IK amplitude in these cells. The intermediate-conductance Ca2+-activated K+ (IKCa channels subject to activation by DCEBIO and to inhibition by TRAM-34 or clotrimazole were functionally expressed in these cells. Unlike cisplatin, OXAL decreased the probability of IKCa-channel openings in a concentration-dependent manner with an IC50 value of 67 µM. No significant change in single-channel conductance of IKCa channels in the presence of OXAL was demonstrated. Neither large-conductance Ca2+-activated K+ channels nor inwardly rectifying K+ currents in these cells were affected in the presence of OXAL. OXAL also suppressed the proliferation and migration of 13-06-MG cells in a concentration- and time-dependent manner. OXAL reduced IKCa-channel activity in LoVo colorectal cancer cells. Taken together, the inhibition by OXAL of IKCa channels would conceivably be an important mechanism through which it acts on the functional activities of glioma cells occurring in vivo.

  5. Myostatin expression, lymphocyte population, and potential cytokine production correlate with predisposition to high-fat diet induced obesity in mice.

    Directory of Open Access Journals (Sweden)

    Jeri-Anne Lyons

    Full Text Available A strong relationship exists between increased inflammatory cytokines and muscle insulin resistance in obesity. This study focused on identifying a relationship between metabolic propensity and myostatin expression in muscle and spleen cells in response to high-fat diet intake. Using a comparative approach, we analyzed the effects of high-fat diet intake on myostatin and follistatin expression, spleen cell composition, and potential cytokine expression in high-fat diet induced obesity (HFDIO resistant (SWR/J and susceptible (C57BL/6 mice models. Results demonstrated overall increased myostatin expression in muscle following high-fat diet intake in HFDIO-susceptible mice, while myostatin expression levels decreased initially in muscle from high-fat diet fed resistant mice. In HFDIO-resistant mice, myostatin expression decreased in spleen, while myostatin increased in spleen tissue from HFDIO-susceptible mice. Proinflammatory cytokine (IL-17, IL-1β, and IFNγ potential increased in splenocytes from HFDIO-susceptible mice. In comparison, C57BL/6 mice fed a high-fat diet exhibited higher frequencies of CD4(+/CD44(hi and CD8(+/CD44(hi cells in the spleen compared to control fed mice. Together, these results suggest that susceptibility to high-fat diet induced obesity could be influenced by local myostatin activity in a tissue-specific manner and that splenocytes exhibit differential cytokine production in a strain-dependent manner. This study sets the stage for future investigations into the interactions between growth, inflammation, and metabolism.

  6. Inhibition of delayed rectifier K+ channels by phenytoin in rat neuroblastoma cells

    OpenAIRE

    Nobile, Mario; Vercellino, Paolo

    1997-01-01

    The action of the anticonvulsant drug phenytoin on K+ currents was investigated in neuroblastoma cells by whole-cell voltage-clamp recording.Neuroblastoma cells expressed an outward K+ current with a voltage- and time-dependence which resembled the delayed-rectifier K+ current found in other cells. When added to the standard external solution at concentrations ranging between 1 and 200 μM, phenytoin reduced the current (n=65). Inhibition was concentration-dependent with a half-maximal inhibit...

  7. Neurotensinergic Excitation of Dentate Gyrus Granule Cells via Gαq-Coupled Inhibition of TASK-3 Channels.

    Science.gov (United States)

    Zhang, Haopeng; Dong, Hailong; Cilz, Nicholas I; Kurada, Lalitha; Hu, Binqi; Wada, Etsuko; Bayliss, Douglas A; Porter, James E; Lei, Saobo

    2016-03-01

    Neurotensin (NT) is a 13-amino acid peptide and serves as a neuromodulator in the brain. Whereas NT has been implicated in learning and memory, the underlying cellular and molecular mechanisms are ill-defined. Because the dentate gyrus receives profound innervation of fibers containing NT and expresses high density of NT receptors, we examined the effects of NT on the excitability of dentate gyrus granule cells (GCs). Our results showed that NT concentration dependently increased action potential (AP) firing frequency of the GCs by the activation of NTS1 receptors resulting in the depolarization of the GCs. NT-induced enhancement of AP firing frequency was not caused indirectly by releasing glutamate, GABA, acetylcholine, or dopamine, but due to the inhibition of TASK-3 K(+) channels. NT-mediated excitation of the GCs was G protein dependent, but independent of phospholipase C, intracellular Ca(2+) release, and protein kinase C. Immunoprecipitation experiment demonstrates that the activation of NTS1 receptors induced the association of Gαq/11 and TASK-3 channels suggesting a direct coupling of Gαq/11 to TASK-3 channels. Endogenously released NT facilitated the excitability of the GCs contributing to the induction of long-term potentiation at the perforant path-GC synapses. Our results provide a cellular mechanism that helps to explain the roles of NT in learning and memory. PMID:25405940

  8. High Fat Diet Feeding Exaggerates Perfluorooctanoic Acid-Induced Liver Injury in Mice via Modulating Multiple Metabolic Pathways

    OpenAIRE

    Tan, Xiaobing; Xie, Guoxiang; Sun, Xiuhua; Li, Qiong; Wei ZHONG; Qiao, Peter; Sun, Xinguo; Jia, Wei; Zhou, Zhanxiang

    2013-01-01

    High fat diet (HFD) is closely linked to a variety of health issues including fatty liver. Exposure to perfluorooctanoic acid (PFOA), a synthetic perfluorinated carboxylic acid, also causes liver injury. The present study investigated the possible interactions between high fat diet and PFOA in induction of liver injury. Mice were pair-fed a high-fat diet (HFD) or low fat control with or without PFOA administration at 5 mg/kg/day for 3 weeks. Exposure to PFOA alone caused elevated plasma alani...

  9. Antiobesity and hypolipidemic effects of lotus leaf hot water extract with taurine supplementation in rats fed a high fat diet

    OpenAIRE

    Du Huan; You Jeong-Soon; Zhao Xu; Park Ji-Yeon; Kim Sung-Hoon; Chang Kyung-Ja

    2010-01-01

    Abstract Background Lotus (Nelumbo nucifera) leaf has been used to treat obesity. The purpose of this study was to investigate the antiobesity and hypolipidemic effects of lotus leaf hot water extract with taurine supplementation in high fat diet-induced obese rats. Methods Four week-old male Sprague-Dawley rats were randomly divided into four groups with 8 rats in each group for a period of 6 weeks (normal diet, N group; high fat diet, HF group; high fat diet + lotus leaf hot water extract, ...

  10. High-fat diet exacerbates renal dysfunction in SHR: reversal by induction of HO-1-adiponectin axis.

    Science.gov (United States)

    Cao, Jian; Inoue, Kazuyoshi; Sodhi, Komal; Puri, Nitin; Peterson, Stephen J; Rezzani, Rita; Abraham, Nader G

    2012-05-01

    High-dietary fat intake is a major risk factor for development of metabolic and cardiovascular-renal dysfunction including obesity, coronary artery disease, hypertension, and chronic renal failure. We examined the effect of a high-fat diet on renal function and morphology in spontaneously hypertensive rats (SHR), a phenotype designed to mimic metabolic syndrome. High-fat diet induced increase (P SnMP) corroborates the role of HO system in mediating such effects. Taken together, our results demonstrate that high-fat diet induces a metabolic syndrome-like phenotype in hypertensive rats, which is amenable to rescue by increases in HO-1- and adiponectin-dependent pathways. PMID:22193921

  11. Liver Fatty Acid Binding Protein Gene-ablation Exacerbates Weight Gain in High-Fat Fed Female Mice

    OpenAIRE

    McIntosh, Avery L.; Atshaves, Barbara P.; Landrock, Danilo; Landrock, Kerstin K.; Martin, Gregory G.; Storey, Stephen M.; Kier, Ann B.; Schroeder, Friedhelm

    2013-01-01

    Loss of liver fatty acid binding protein (L-FABP) decreases long chain fatty acid uptake and oxidation in primary hepatocytes and in vivo. On this basis, L-FABP gene ablation would potentiate high-fat diet-induced weight gain and weight gain/energy intake. While this was indeed the case when L-FABP null (−/−) mice on the C57BL/6NCr background were pair-fed high fat diet, whether this would also be observed under high-fat diet fed ad libitum was not known. Therefore, this possibility was exami...

  12. Mitochondrial KATP channel inhibition blunts arrhythmia protection in ischemic exercised hearts

    OpenAIRE

    Quindry, John C.; Schreiber, Lindsey; Hosick, Peter; Wrieden, Jenna; Irwin, J. Megan; Hoyt, Emily

    2010-01-01

    The mechanisms responsible for anti-arrhythmic protection during ischemia-reperfusion (IR) in exercised hearts are not fully understood. The purpose of this investigation was to examine whether the ATP-sensitive potassium channels in the mitochondria (mito KATP) and sarcolemma (sarc KATP) provide anti-arrhythmic protection in exercised hearts during IR. Male Sprague-Dawley rats were randomly assigned to cardioprotective treadmill exercise or sedentary conditions before IR (I = 20 min, R = 30 ...

  13. Inhibition of Recombinant Human T-type Calcium Channels by Δ9-Tetrahydrocannabinol and Cannabidiol*

    OpenAIRE

    Ross, Hamish Redmond; Napier, Ian; Connor, Mark

    2008-01-01

    Δ9-Tetrahydrocannabinol (THC) and cannabidiol (CBD) are the most prevalent biologically active constituents of Cannabis sativa. THC is the prototypic cannabinoid CB1 receptor agonist and is psychoactive and analgesic. CBD is also analgesic, but it is not a CB1 receptor agonist. Low voltage-activated T-type calcium channels, encoded by the CaV3 gene family, regulate the excitability of many cells, including neurons involved in nociceptive processing. We examined the eff...

  14. Pharmacological Inhibition of Voltage-gated Ca(2+) Channels for Chronic Pain Relief.

    Science.gov (United States)

    Lee, Seungkyu

    2013-12-01

    Chronic pain is a major therapeutic problem as the current treatment options are unsatisfactory with low efficacy and deleterious side effects. Voltage-gated Ca2+ channels (VGCCs), which are multi-complex proteins consisting of α1, β, γ, and α2δ subunits, play an important role in pain signaling. These channels are involved in neurogenic inflammation, excitability, and neurotransmitter release in nociceptors. It has been previously shown that N-type VGCCs (Cav2.2) are a major pain target. U.S. FDA approval of three Cav2.2 antagonists, gabapentin, pregabalin, and ziconotide, for chronic pain underlies the importance of this channel subtype. Also, there has been increasing evidence that L-type (Cav1.2) or T-type (Cav3.2) VGCCs may be involved in pain signaling and chronic pain. In order to develop novel pain therapeutics and to understand the role of VGCC subtypes, discovering subtype selective VGCC inhibitors or methods that selectively target the inhibitor into nociceptors would be essential. This review describes the various VGCC subtype inhibitors and the potential of utilizing VGCC subtypes as targets of chronic pain. Development of VGCC subtype inhibitors and targeting them into nociceptors will contribute to a better understanding of the roles of VGCC subtypes in pain at a spinal level as well as development of a novel class of analgesics for chronic pain. PMID:24396337

  15. Structural Basis for the Function and Inhibition of an Influenze Virus Proton Channel

    Energy Technology Data Exchange (ETDEWEB)

    Stouffer,A.; Acharya, R.; Salom, D.; Levine, A.; Di Costanzo, L.; Soto, C.; Tershko, V.; Nanda, V.; Stayrook, S.; DeGrado, W.

    2008-01-01

    The M2 protein from influenza A virus is a pH-activated proton channel that mediates acidification of the interior of viral particles entrapped in endosomes. M2 is the target of the anti-influenza drugs amantadine and rimantadine; recently, resistance to these drugs in humans, birds and pigs has reached more than 90% (ref. 1). Here we describe the crystal structure of the transmembrane-spanning region of the homotetrameric protein in the presence and absence of the channel-blocking drug amantadine. pH-dependent structural changes occur near a set of conserved His and Trp residues that are involved in proton gating2. The drug-binding site is lined by residues that are mutated in amantadine-resistant viruses3, 4. Binding of amantadine physically occludes the pore, and might also perturb the pKa of the critical His residue. The structure provides a starting point for solving the problem of resistance to M2-channel blockers.

  16. Inhibition of connexin43 gap junction channels by the endocrine disruptor ioxynil

    International Nuclear Information System (INIS)

    Gap junctions are intercellular plasma membrane domains containing channels that mediate transport of ions, metabolites and small signaling molecules between adjacent cells. Gap junctions play important roles in a variety of cellular processes, including regulation of cell growth and differentiation, maintenance of tissue homeostasis and embryogenesis. The constituents of gap junction channels are a family of trans-membrane proteins called connexins, of which the best-studied is connexin43. Connexin43 functions as a tumor suppressor protein in various tissue types and is frequently dysregulated in human cancers. The pesticide ioxynil has previously been shown to act as an endocrine disrupting chemical and has multiple effects on the thyroid axis. Furthermore, both ioxynil and its derivative ioxynil octanoate have been reported to induce tumors in animal bioassays. However, the molecular mechanisms underlying the possible tumorigenic effects of these compounds are unknown. In the present study we show that ioxynil and ioxynil octanoate are strong inhibitors of connexin43 gap junction channels. Both compounds induced rapid loss of connexin43 gap junctions at the plasma membrane and increased connexin43 degradation. Ioxynil octanoate, but not ioxynil, was found to be a strong activator of ERK1/2. The compounds also had different effects on the phosphorylation status of connexin43. Taken together, the data show that ioxynil and ioxynil octanoate are potent inhibitors of intercellular communication via gap junctions.

  17. Ethanolic extract of Taheebo attenuates increase in body weight and fatty liver in mice fed a high-fat diet.

    Science.gov (United States)

    Choi, Won Hee; Um, Min Young; Ahn, Jiyun; Jung, Chang Hwa; Park, Myung Kyu; Ha, Tae Youl

    2014-01-01

    We evaluated whether intake of an ethanolic extract of Taheebo (TBE) from Tabebuia avellanedae protects against body weight increase and fat accumulation in mice with high-fat diet (HFD)-induced obesity. Four-week old male C57BL/6 mice were fed a HFD (25% fat, w/w) for 11 weeks. The diet of control (HFD) mice was supplemented with vehicle (0.5% sodium carboxymethyl cellulose by gavage); the diet of experimental (TBE) mice was supplemented with TBE (150 mg/kg body weight/day by gavage). Mice administered TBE had significantly reduced body weight gain, fat accumulation in the liver, and fat pad weight, compared to HFD mice. Reduced hypertrophy of fat cells was also observed in TBE mice. Mice administered TBE also showed significantly lower serum levels of triglycerides, insulin, and leptin. Lipid profiles and levels of mRNAs and proteins related to lipid metabolism were determined in liver and white adipose tissue of the mice. Expression of mRNA and proteins related to lipogenesis were decreased in TBE-administered mice compared to mice fed HFD alone. These results suggest that TBE inhibits obesity and fat accumulation by regulation of gene expression related to lipid metabolism in HFD-induced obesity in mice. PMID:25299819

  18. Ethanolic Extract of Taheebo Attenuates Increase in Body Weight and Fatty Liver in Mice Fed a High-Fat Diet

    Directory of Open Access Journals (Sweden)

    Won Hee Choi

    2014-10-01

    Full Text Available We evaluated whether intake of an ethanolic extract of Taheebo (TBE from Tabebuia avellanedae protects against body weight increase and fat accumulation in mice with high-fat diet (HFD-induced obesity. Four-week old male C57BL/6 mice were fed a HFD (25% fat, w/w for 11 weeks. The diet of control (HFD mice was supplemented with vehicle (0.5% sodium carboxymethyl cellulose by gavage; the diet of experimental (TBE mice was supplemented with TBE (150 mg/kg body weight/day by gavage. Mice administered TBE had significantly reduced body weight gain, fat accumulation in the liver, and fat pad weight, compared to HFD mice. Reduced hypertrophy of fat cells was also observed in TBE mice. Mice administered TBE also showed significantly lower serum levels of triglycerides, insulin, and leptin. Lipid profiles and levels of mRNAs and proteins related to lipid metabolism were determined in liver and white adipose tissue of the mice. Expression of mRNA and proteins related to lipogenesis were decreased in TBE-administered mice compared to mice fed HFD alone. These results suggest that TBE inhibits obesity and fat accumulation by regulation of gene expression related to lipid metabolism in HFD-induced obesity in mice.

  19. The Resin from Protium heptaphyllum Prevents High-Fat Diet-Induced Obesity in Mice: Scientific Evidence and Potential Mechanisms

    Directory of Open Access Journals (Sweden)

    Karine Maria Martins Bezerra Carvalho

    2015-01-01

    Full Text Available Herbal compounds rich in triterpenes are well known to regulate glucose and lipid metabolism and to have beneficial effects on metabolic disorders. The present study investigated the antiobesity properties of resin from Protium heptaphyllum (RPH and the possible mechanisms in mice fed a high-fat diet (HFD for 15 weeks. Mice treated with RPH showed decreases in body weight, net energy intake, abdominal fat accumulation, plasma glucose, amylase, lipase, triglycerides, and total cholesterol relative to their respective controls, which were RPH unfed. Additionally, RPH treatment, while significantly elevating the plasma level of ghrelin hormone, decreased the levels of insulin, leptin, and resistin. Besides, HFD-induced increases in plasma levels of proinflammatory mediators TNF-α, IL-6, and MCP-1 were significantly lowered by RPH. Furthermore, in vitro studies revealed that RPH could significantly inhibit the lipid accumulation in 3T3-L1 adipocytes (measured by Oil-Red O staining at concentrations up to 50 μg/mL. These findings suggest that the antiobese potential of RPH is largely due to its modulatory effects on various hormonal and enzymatic secretions related to fat and carbohydrate metabolism and to the regulation of obesity-associated inflammation.

  20. PGC-1/Spargel Counteracts High-Fat-Diet-Induced Obesity and Cardiac Lipotoxicity Downstream of TOR and Brummer ATGL Lipase

    Directory of Open Access Journals (Sweden)

    Soda Balla Diop

    2015-03-01

    Full Text Available Obesity and metabolic syndrome are associated with an increased risk for lipotoxic cardiomyopathy, which is strongly correlated with excessive accumulation of lipids in the heart. Obesity- and type-2-diabetes-related disorders have been linked to altered expression of the transcriptional cofactor PGC-1α, which regulates the expression of genes involved in energy metabolism. Using Drosophila, we identify PGC-1/spargel (PGC-1/srl as a key antagonist of high-fat diet (HFD-induced lipotoxic cardiomyopathy. We find that HFD-induced lipid accumulation and cardiac dysfunction are mimicked by reduced PGC-1/srl function and reversed by PGC-1/srl overexpression. Moreover, HFD feeding lowers PGC-1/srl expression by elevating TOR signaling and inhibiting expression of the Drosophila adipocyte triglyceride lipase (ATGL (Brummer, both of which function as upstream modulators of PGC-1/srl. The lipogenic transcription factor SREBP also contributes to HFD-induced cardiac lipotoxicity, likely in parallel with PGC-1/srl. These results suggest a regulatory network of key metabolic genes that modulates lipotoxic heart dysfunction.

  1. High fat diet-induced TGF-β/Gbb signaling provokes insulin resistance through the tribbles expression.

    Science.gov (United States)

    Hong, Seung-Hyun; Kang, Moonyoung; Lee, Kyu-Sun; Yu, Kweon

    2016-01-01

    Hyperglycemia, hyperlipidemia, and insulin resistance are hallmarks of obesity-induced type 2 diabetes, which is often caused by a high-fat diet (HFD). However, the molecular mechanisms underlying HFD-induced insulin resistance have not been elucidated in detail. In this study, we established a Drosophila model to investigate the molecular mechanisms of HFD-induced diabetes. HFD model flies recapitulate mammalian diabetic phenotypes including elevated triglyceride and circulating glucose levels, as well as insulin resistance. Expression of glass bottom boat (gbb), a Drosophila homolog of mammalian transforming growth factor-β (TGF-β), is elevated under HFD conditions. Furthermore, overexpression of gbb in the fat body produced obese and insulin-resistant phenotypes similar to those of HFD-fed flies, whereas inhibition of Gbb signaling significantly ameliorated HFD-induced metabolic phenotypes. We also discovered that tribbles, a negative regulator of AKT, is a target gene of Gbb signaling in the fat body. Overexpression of tribbles in flies in the fat body phenocopied the metabolic defects associated with HFD conditions or Gbb overexpression, whereas tribbles knockdown rescued these metabolic phenotypes. These results indicate that HFD-induced TGF-β/Gbb signaling provokes insulin resistance by increasing tribbles expression. PMID:27484164

  2. Polyphenol-Rich Fraction of Ecklonia cava Improves Nonalcoholic Fatty Liver Disease in High Fat Diet-Fed Mice

    Directory of Open Access Journals (Sweden)

    Eun-Young Park

    2015-11-01

    Full Text Available Ecklonia cava (E. cava; CA is an edible brown alga with beneficial effects in diabetes via regulation of various metabolic processes such as lipogenesis, lipolysis, inflammation, and the antioxidant defense system in liver and adipose tissue. We investigated the effect of the polyphenol-rich fraction of E. cava produced from Gijang (G-CA on nonalcoholic fatty liver disease (NAFLD in high-fat diet (HFD-fed mice. C57BL6 mice were fed a HFD for six weeks and then the HFD group was administered 300 mg/kg of G-CA extracts by oral intubation for 10 weeks. Body weight, fat mass, and serum biochemical parameters were reduced by G-CA extract treatment. MRI/MRS analysis showed that liver fat and liver volume in HFD-induced obese mice were reduced by G-CA extract treatment. Further, we analyzed hepatic gene expression related to inflammation and lipid metabolism. The mRNA expression levels of inflammatory cytokines and hepatic lipogenesis-related genes were decreased in G-CA-treated HFD mice. The mRNA expression levels of cholesterol 7 alpha-hydroxylase 1 (CYP7A1, the key enzyme in bile acid synthesis, were dramatically increased by G-CA treatment in HFD mice. We suggest that G-CA treatment ameliorated hepatic steatosis by inhibiting inflammation and improving lipid metabolism.

  3. Carnosic acid as a major bioactive component in rosemary extract ameliorates high-fat-diet-induced obesity and metabolic syndrome in mice.

    Science.gov (United States)

    Zhao, Yantao; Sedighi, Rashin; Wang, Pei; Chen, Huadong; Zhu, Yingdong; Sang, Shengmin

    2015-05-20

    In this study, we investigated the preventive effects of carnosic acid (CA) as a major bioactive component in rosemary extract (RE) on high-fat-diet-induced obesity and metabolic syndrome in mice. The mice were given a low-fat diet, a high-fat diet or a high-fat diet supplemented with either 0.14% or 0.28% (w/w) CA-enriched RE (containing 80% CA, RE#1L and RE#1H), or 0.5% (w/w) RE (containing 45% CA, RE#2), for a period of 16 weeks. There was the same CA content in the RE#1H and RE#2 diets and half of this amount in the RE#1L diet. The dietary RE supplementation significantly reduced body weight gain, percent of fat, plasma ALT, AST, glucose, insulin levels, liver weight, liver triglyceride, and free fatty acid levels in comparison with the mice fed with a HF diet without RE treatment. RE administration also decreased the levels of plasma and liver malondialdehyde, advanced glycation end products (AGEs), and the liver expression of receptor for AGE (RAGE) in comparison with those for mice of the HF group. Histological analyses of liver samples showed decreased lipid accumulation in hepatocytes in mice administrated with RE in comparison with that of HF-diet-fed mice. Meanwhile, RE administration enhanced fecal lipid excretion to inhibit lipid absorption and increased the liver GSH/GSSG ratio to perform antioxidant activity compared with HF group. Our results demonstrate that rosemary is a promising dietary agent to reduce the risk of obesity and metabolic syndrome. PMID:25929334

  4. Platycodon grandiflorum extract represses up-regulated adipocyte fatty acid binding protein triggered by a high fat feeding in obese rats

    Institute of Scientific and Technical Information of China (English)

    Yoon Shin Park; Yoosik Yoon; Hong Seok Ahn

    2007-01-01

    AIM: To investigate the effect of Platycodon grandiflorum extract (PGE) on lipid metabolism and FABP mRNA expression in subcutaneous adipose tissue of high fat diet-induced obese rats.METHODS: PGE was treated to investigate the inhibitory effect on the pre-adipocyte 3T3-L1 differentiation and pancreatic lipase activity. Male Sprague-Dawley rats with an average weight of 439.03 ± 7.61 g were divided into four groups: the control groups that fed an experimental diet alone (C and H group) and PGE treatment groups that administered PGE along with a control diet or HFD at a concentration of 150 mg/kg body weight (C + PGE and H + PGE group, respectively) for 7 wk. Plasma total cholesterol (TC) and triglycerol (TG) concentrations were measured from the tail vein of rats. Adipocyte cell area was measured from subcutaneous adipose tissue and the fatty acid binding protein (FABP) mRNA expression was analyzed by northern blot analysis.RESULTS: PGE treatment inhibited 3T3-L1 pre-adipocyte differentiation and fat accumulation, and also decreased pancreatic lipase activity. In this experiment, PGE significantly reduced plasma TC and TG concentrations as well as body weight and subcutaneous adipose tissue weight. PGE also significantly decreased the size of subcutaneous adipocytes. Furthermore, it significantly repressed the up-regulation of FABP mRNA expression induced by a high-fat feeding in subcutaneous adipose tissue.CONCLUSION: PGE has a plasma lipid lowering-effect and anti-obesity effect in obese rats fed a high fat diet.From these results, we can suggest the possibility that PGE can be used as a food ingredient or drug component to therapeutically control obesity.

  5. Baclofen and adenosine inhibition of synaptic transmission at CA3-CA1 synapses display differential sensitivity to K+ channel blockade.

    Science.gov (United States)

    Skov, Jane; Andreasen, Mogens; Hablitz, John J; Nedergaard, Steen

    2011-05-01

    The metabotropic GABA(B) and adenosine A(1) receptors mediate presynaptic inhibition through regulation of voltage-dependent Ca(2+) channels, whereas K(+) channel regulation is believed to have no role at the CA3-CA1 synapse. We show here that the inhibitory effect of baclofen (20 μM) and adenosine (300 μM) on field EPSPs are differentially sensitive to Cs(+) (3.5 mM) and Ba(2+) (200 μM), but not 4-aminopyridine (100 μM). Barium had no effect on paired-pulse facilitation (PPF) in itself, but gave significant reduction (14 ± 5%) when applied in the presence of baclofen, but not adenosine, suggesting that the effect is presynaptic and selective on the GABA(B) receptor-mediated response. The effect of Ba(2+) on PPF was not mimicked by tertiapin (30 nM), indicating that the underlying mechanism does not involve GIRK channels. Barium did not affect PPF in slices from young rats (P7-P8), suggesting developmental regulation. The above effects of Ba(2+) on adult tissue were reproduced when measuring evoked whole-cell EPSCs from CA1 pyramidal neurons: PPF was reduced by 22 ± 3% in the presence of baclofen and unaltered in adenosine. In contrast, Ba(2+) caused no significant change in frequency or amplitude of miniature EPSCs. The Ba(2+)-induced reduction of PPF was antagonized by LY341495, suggesting metabotropic glutamate receptor involvement. We propose that these novel effects of Ba(2+) and Cs(+) are exerted through blockade of inwardly rectifying K(+) channels in glial cells, which are functionally interacting with the GABA(B) receptor-dependent glutamate release that generates heterosynaptic depression. PMID:21274618

  6. Anti-obesity efficacy of nanoemulsion oleoresin capsicum in obese rats fed a high-fat diet

    Directory of Open Access Journals (Sweden)

    Kim JY

    2014-01-01

    Full Text Available Joo-Yeon Kim,1,* Mak-Soon Lee,1,* Sunyoon Jung,1 Hyunjin Joo,1 Chong-Tai Kim,2 In-Hwan Kim,3 Sangjin Seo,1 Soojung Oh,1 Yangha Kim11Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, Republic of Korea; 2Functional Materials Research Group, Korea Food Research Institute, Seongnam, Gyeonggi, Republic of Korea; 3Department of Food and Nutrition, Korea University, Seoul, Republic of Korea *These authors contributed equally to this workPurpose: This study determined the effects of oleoresin capsicum (OC and nanoemulsion OC (NOC on obesity in obese rats fed a high-fat diet.Methods: The rats were randomly separated into three groups: a high-fat (HF diet group, HF + OC diet group, and HF + NOC diet group. All groups were fed the diet and water ad libitum for 14 weeks.Results: NOC reduced the body weight and adipose tissue mass, whereas OC did not. OC and NOC reduced mRNA levels of adipogenic genes, including peroxisome proliferator-activated receptor (PPAR-γ, sterol regulatory element-binding protein-1c, and fatty acid-binding protein in white adipose tissue. The mRNA levels of genes related to β-oxidation or thermogenesis including PPAR-α, palmitoyltransferase-1α, and uncoupling protein-2 were increased by the OC and NOC relative to the HF group. Both OC and NOC clearly stimulated AMP-activated protein kinase (AMPK activity. In particular, PPAR-α, palmitoyltransferase-1α, uncoupling protein-2 expression, and AMPK activity were significantly increased in the NOC group compared to in the OC group. NOC decreased glycerol-3-phosphate dehydrogenase activity whereas OC did not.Conclusion: From these results, NOC could be suggested as a potential anti-obesity agent in obese rats fed a HF diet. The effects of the NOC on obesity were associated with changes of multiple gene expression, activation of AMPK, and inhibition of glycerol-3-phosphate dehydrogenase in white adipose tissue.Keywords: oleoresin capsicum

  7. Rat Models of Diet-Induced Obesity and High Fat/Low Dose Streptozotocin Type 2 Diabetes: Effect of Reversal of High Fat Diet Compared to Treatment with Enalapril or Menhaden Oil on Glucose Utilization and Neuropathic Endpoints

    OpenAIRE

    Amey Holmes; Coppey, Lawrence J.; Eric P. Davidson; Yorek, Mark A.

    2015-01-01

    We examined whether reversal of high fat diet, stimulating weight loss, compared to two treatments previously shown to have beneficial effects, could improve glucose utilization and peripheral neuropathy in animal models of obesity and type 2 diabetes. Rats were fed a high fat diet and treated with a low dose of streptozotocin to create models of diet induced obesity or type 2 diabetes, respectively. Afterwards, rats were transferred to a normal diet or treated with enalapril or dietary enric...

  8. Effects of Orlistat and herbal mixture extract on brain, testes functions and oxidative stress biomarkers in a rat model of high fat diet

    OpenAIRE

    Galaly, Sanaa R; Hozayen, Walaa G.; Amin, Kamal A; Shimaa M. Ramadan

    2014-01-01

    This study was designed to assess the effectiveness of herbal mixture extracts of pumpkin seed oil, peanuts shell and Orlistat on brain, testes functions, oxidative stress biomarkers and histopathological changes in male albino rats administered high fat diet. Fifty male rats were divided into four groups: 1st administered normal diet, 2nd administered high fat diet, 3rd administered high fat diet with Orlistat and 4th administered high fat diet with herbal mix. A group of rats were fed wi...

  9. Anti-addiction drug ibogaine inhibits hERG channels: a cardiac arrhythmia risk.

    Science.gov (United States)

    Koenig, Xaver; Kovar, Michael; Boehm, Stefan; Sandtner, Walter; Hilber, Karlheinz

    2014-03-01

    Ibogaine, an alkaloid derived from the African shrub Tabernanthe iboga, has shown promising anti-addictive properties in animals. Anecdotal evidence suggests that ibogaine is also anti-addictive in humans. Thus, it alleviates drug craving and impedes relapse of drug use. Although not licensed as therapeutic drug, and despite evidence that ibogaine may disturb the rhythm of the heart, this alkaloid is currently used as an anti-addiction drug in alternative medicine. Here, we report that therapeutic concentrations of ibogaine reduce currents through human ether-a-go-go-related gene potassium channels. Thereby, we provide a mechanism by which ibogaine may generate life-threatening cardiac arrhythmias. PMID:22458604

  10. Positive correlation between serum taurine and adiponectin levels in high-fat diet-induced obesity rats.

    Science.gov (United States)

    You, Jeong Soon; Zhao, Xu; Kim, Sung Hoon; Chang, Kyung Ja

    2013-01-01

    The purpose of this study was to investigate the relationship between serum taurine level and serum adiponectin or leptin levels in high-fat diet-induced obesity rats. Five-week-old male Sprague-Dawley rats were randomly divided into three groups for a period of 8 weeks (normal diet, N group; high-fat diet, HF group; high-fat diet + taurine, HFT group). Taurine was supplemented by dissolving in feed water (3% w/v), and the same amount of distilled water was orally administrated to N and HF groups. In serum, adiponectin level was higher in HFT group compared to HF group. The serum taurine level was negatively correlated with serum total cholesterol (TC) level and positively correlated with serum adiponectin level. These results suggest that dietary taurine supplementation has beneficial effects on total cholesterol and adiponectin levels in high-fat diet-induced obesity rats. PMID:23392875

  11. The link between high-fat meals and postprandial activation of blood coagulation factor VII possibly involves kallikrein

    DEFF Research Database (Denmark)

    Larsen, L F; Marckmann, P; Bladbjerg, Else-Marie;

    2000-01-01

    Contrary to low-fat meals, high-fat meals are known to cause postprandial factor VII (FVII) activation, but the mechanism is unknown. To study the postprandial FVII activation in detail, 18 young men consumed in randomized order high-fat or low-fat test meals. Fasting and non-fasting blood samples......-rich lipoproteins activate prokallikrein postprandially, which might form an important initial event in FVII activation after consumption of high-fat meals....... were collected. The high-fat test was associated with an increase in plasma triglyceride and kallikrein concentrations and postprandial FVII activation (p<0.001). Plasma kallikrein was strongly associated with triglycerides in fasting and non-fasting samples (r2=0.74-0.87, p<0.0001), suggesting that...

  12. Dietary krill oil supplementation reduces hepatic steatosis, glycemia, and hypercholesterolemia in high-fat-fed mice.

    Science.gov (United States)

    Tandy, Sally; Chung, Rosanna W S; Wat, Elaine; Kamili, Alvin; Berge, Kjetil; Griinari, Mikko; Cohn, Jeffrey S

    2009-10-14

    Krill oil (KO) is rich in n-3 fatty acids that are present in phospholipids rather than in triglycerides. In the present study, we investigated the effects of dietary KO on cardiometabolic risk factors in male C57BL/6 mice fed a high-fat diet. Mice (n = 6-10 per group) were fed for 8 weeks either: (1) a nonpurified chow diet (N); (2) a high-fat semipurified diet containing 21 wt % buttermilk + 0.15 wt % cholesterol (HF); (3) HF supplemented with 1.25 wt % KO (HFKO1.25); (4) HF with 2.5 wt % KO (HFKO2.5); or (5) HF with 5 wt % KO (HFKO5.0). Dietary KO supplementation caused a significant reduction in liver wt (i.e., hepatomegaly) and total liver fat (i.e., hepatic steatosis), due to a dose-dependent reduction in hepatic triglyceride (mean +/- SEM: 35 +/- 6, 47 +/- 4, and 51 +/- 5% for HFKO1.25, -2.5, and -5.0 vs HF, respectively, P < 0.001) and cholesterol (55 +/- 5, 66 +/- 3, and 71 +/- 3%, P < 0.001). Serum cholesterol levels were reduced by 20 +/- 3, 29 +/- 4, and 29 +/- 5%, and blood glucose was reduced by 36 +/- 5, 34 +/- 6, and 42 +/- 6%, respectively. Serum adiponectin was increased in KO-fed animals (HF vs HFKO5.0: 5.0 +/- 0.2 vs 7.5 +/- 0.6 microg/mL, P < 0.01). These results demonstrate that dietary KO is effective in improving metabolic parameters in mice fed a high-fat diet, suggesting that KO may be of therapeutic value in patients with the metabolic syndrome and/or nonalcoholic fatty liver disease. PMID:19761211

  13. Glycogen repletion and exercise endurance in rats adapted to a high fat diet.

    Science.gov (United States)

    Conlee, R K; Hammer, R L; Winder, W W; Bracken, M L; Nelson, A G; Barnett, D W

    1990-03-01

    It is well accepted that exercise endurance is directly related to the amount of carbohydrate stored in muscle and that a low carbohydrate diet reduces glycogen storage and exercise performance. However, more recent evidence has shown that when the organism adapts to a high fat diet endurance is not hindered. The present study was designed to test that claim and to further determine if animals adapted to a high fat diet could recover from exhausting exercise and exercise again in spite of carbohydrate deprivation. Fat-adapted (3 to 4 weeks, 78% fat, 1% carbohydrates) rats (FAT) ran (28 m/min, 10% grade) as long as carbohydrate-fed (69% carbohydrates) animals (CHO) (115 v 109 minutes, respectively) in spite of lower pre-exercise glycogen levels in red vastus muscle (36 v 54 mumols/g) and liver (164 v 313 mumols/g) in the FAT group. Following 72 hours of recovery on the FAT diet, glycogen in muscle had replenished to 42 mumols/g (v 52 for CHO) and liver glycogen to 238 mumols/g (v 335 for CHO). The animals were run to exhaustion a second time and run times were again similar (122 v 132 minutes FAT v CHO). When diets were switched after run 1, FAT-adapted animals, which received carbohydrates for 72 hours, restored muscle and liver glycogen (48 and 343 mumols/g, respectively) and then ran longer (144 minutes) than CHO-adapted animals (104 minutes) that ate fat for 72 hours and that had reduced glycogen repletion. We conclude that, in contrast to the classic CHO loading studies in humans that involved acute (72 hours) fat feedings and subsequently reduced endurance, rats adapted to a high fat diet do not have a decrease in endurance capacity even after recovery from previous exhausting work bouts. Part of this adaptation may involve the increased storage and utilization of intramuscular triglycerides (TG) as observed in the present experiment. PMID:2308519

  14. Thermosensing mechanisms and their impairment by high-fat diet in orexin neurons.

    Science.gov (United States)

    Belanger-Willoughby, N; Linehan, V; Hirasawa, M

    2016-06-01

    In homeotherms, the hypothalamus controls thermoregulatory and adaptive mechanisms in energy balance, sleep-wake and locomotor activity to maintain optimal body temperature. Orexin neurons may be involved in these functions as they promote thermogenesis, food intake and behavioral arousal, and are sensitive to temperature and metabolic status. How thermal and energy balance signals are integrated in these neurons is unknown. Thus, we investigated the cellular mechanisms of thermosensing in orexin neurons and their response to a change in energy status using whole-cell patch clamp on rat brain slices. We found that warming induced an increase in miniature excitatory postsynaptic current (EPSC) frequency, which was blocked by the transient receptor potential vanilloid-1 (TRPV1) receptor antagonist AMG9810 and mimicked by its agonist capsaicin, suggesting that the synaptic effect is mediated by heat-sensitive TRPV1 channels. Furthermore, warming inhibits orexin neurons by activating ATP-sensitive potassium (KATP) channels, an effect regulated by uncoupling protein 2 (UCP2), as the UCP2 inhibitor genipin abolished this response. These properties are unique to orexin neurons in the lateral hypothalamus, as neighboring melanin-concentrating hormone neurons showed no response to warming within the physiological temperature range. Interestingly, in rats fed with western diet for 1 or 11weeks, orexin neurons had impaired synaptic and KATP response to warming. In summary, this study reveals several mechanisms underlying thermosensing in orexin neurons and their attenuation by western diet. Overeating induced by western diet may in part be due to impaired orexin thermosensing, as post-prandial thermogenesis may promote satiety and lethargy by inhibiting orexin neurons. PMID:26964685

  15. Early Skeletal Muscle Adaptations to Short-Term High-Fat Diet in Humans Prior to Changes in Insulin Sensitivity

    OpenAIRE

    Anderson, Angela S.; Haynie, Kimberly R.; McMillan, Ryan P; Osterberg, Kristen L.; Boutagy, Nabil E.; Frisard, Madlyn I.; Davy, Brenda M.; Davy, Kevin P.; Hulver, Matthew W.

    2015-01-01

    Objective The purpose of this investigation was to understand the metabolic adaptations to a short-term (5 days), isocaloric, high fat diet (HFD) in healthy, young males. Methods Two studies were undertaken with 12 subjects. Study 1 investigated the effect of the HFD on skeletal muscle substrate metabolism and insulin sensitivity. Study 2 assessed the metabolic and transcriptional response in skeletal muscle to the transition from a fasted-to-fed state using a high fat meal challenge prior to...

  16. Maternal high fat and/or salt consumption induces sex-specific inflammatory and nutrient transport in the rat placenta

    OpenAIRE

    Clare M. Reynolds; Mark H. Vickers; Harrison, Claudia J.; Segovia, Stephanie A.; Gray, Clint

    2015-01-01

    Maternal high fat and salt consumption are associated with developmental programming of disease in adult offspring. Inadequacies in placental nutrient transport may explain these ‘programmed effects’. Diet-induced inflammation may have detrimental effects on placental function leading to alteration of key nutrient transporters. We examined the effects of maternal high fat and/or salt diets on markers of placental nutrient transport and inflammation. Sprague–Dawley rats were assigned to (1) co...

  17. Apricot and pumpkin oils reduce plasma cholesterol and triacylglycerol concentrations in rats fed a high-fat diet

    OpenAIRE

    Ramadan, Mohamed F.; Zayed, R.; Abozid, M.; Asker, M. M. S.

    2011-01-01

    Non-conventional oilseeds are being taken into greater consideration because their constituents have unique chemical properties and may increase the supply of edible oils. The purpose of the present study was to investigate the effect of apricot kernel oil (AO) and pumpkin kernel oil (PO) on the lipid profiles and liver functions of rats fed high fat diets. The high fat diet resulted in great alterations in plasma lipid profiles and liver functions. Twenty-four male albino rats were used over...

  18. Arctium lappa ameliorates endothelial dysfunction in rats fed with high fat/cholesterol diets

    OpenAIRE

    Lee Yun; Choi Deok; Cho Guk; Kim Jin; Kang Dae; Lee Ho

    2012-01-01

    Abstract Background Arctium lappa L. (Asteraceae), burdock, is a medicinal plant that is popularly used for treating hypertension, gout, hepatitis, and other inflammatory disorders. This study was performed to test the effect of ethanol extract of Arctium lappa L. (EAL) seeds on vascular reactivity and inflammatory factors in rats fed a high fat/cholesterol diet (HFCD). Method EAL-I (100 mg·kg−1/day), EAL-II (200 mg·kg−1/day), and fluvastatin (3 mg·kg−1/day) groups initially received HFCD alo...

  19. The influence of a high-fat meal on fat taste thresholds.

    Science.gov (United States)

    Newman, Lisa P; Torres, Susan J; Bolhuis, Dieuwerke P; Keast, Russell S J

    2016-06-01

    A high-fat diet for four weeks has been shown to attenuate fat taste sensitivity in healthy weight individuals. However, there is minimal evidence as to whether a single high-fat meal immediately prior to fat taste threshold testing has an effect on thresholds. Therefore, the aim of the study was to determine the effect of a high-fat meal immediately prior to detection threshold testing for oleic acid (C18:1). Thirty-two participants (15 males, 17 females, aged 39.1 ± 3.1 years, Body Mass Index 23.1 ± 0.7 kg/m(2)) attended three laboratory sessions. In each session, participants were randomly assigned to one of three different types of breakfast: a high-fat (60% energy from fat), or low-fat (20% energy from fat) or macronutrient balanced (33% energy from fat) frittata. Fat taste thresholds were evaluated using ascending forced choice triangle tests on two occasions each day; once one-hour post breakfast and then one-hour post the completion of the first threshold test. There was no effect of breakfast type on fat taste detection thresholds for the first testing session of each day (P = 0.288), or the second testing session of each day (P = 0.754). There was also no effect of breakfast within each day (day 1: P = 0.198, day 2: P = 0.199, day 3: P = 0.125). There was no effect of macronutrient composition on the ability of participants to rank the level of fat in food (P = 0.345), or preference for the level of fat in food (P = 0.187-0.868). This study provides preliminary evidence that the composition of the meal consumed by a participant immediately prior to testing does not affect fat taste thresholds. PMID:26964689

  20. Anti-obesity effects of black ginseng extract in high fat diet-fed mice

    OpenAIRE

    Lee, Mi Ra; Kim, Byung Chan; Kim, Ran; Oh, Hyun In; Kim, Hyun Kyoung; Choi, Kang Ju; Sung, Chang Keun

    2013-01-01

    Black ginseng is produced by a repeated steaming process. The aim of this study was to investigate the anti-obesity effects of black ginseng ethanol extract (BG-EE) in high fat (HF) diet-fed mice. Two groups were fed either a normal control (NC) diet or a HF diet (45% kcal fat). The other three groups were given a HF diet supplemented with 1% BG-EE, 3% BG-EE, and 5% BG-EE for 12 wk. The anti-obesity effects of the BG-EE supplement on body weight, the development of fat mass, and lipid mechani...

  1. Consumption of a High-Fat Diet Induces Central Insulin Resistance Independent of Adiposity

    OpenAIRE

    Clegg, Deborah J.; Gotoh, Koro; Kemp, Christopher; Wortman, Matthew D.; Benoit, Stephen C.; Brown, Lynda M.; D’Alessio, David; Tso, Patrick; Seeley, Randy J.; Woods, Stephen C

    2011-01-01

    Plasma insulin enters the CNS where it interacts with insulin receptors in areas that are related to energy homeostasis and elicits a decrease of food intake and body weight. Here, we demonstrate that consumption of a high-fat (HF) diet impairs the central actions of insulin. Male Long-Evans rats were given chronic (70-day) or acute (3-day) ad libitum access to HF, low-fat (LF), or chow diets. Insulin administered into the 3rd-cerebral ventricle (i3vt) decreased food intake and body weight of...

  2. Nicotine in Combination With a High-Fat Diet Causes Intramyocellular Mitochondrial Abnormalities in Male Mice

    OpenAIRE

    Sinha-Hikim, Indrani; Friedman, Theodore C; Shin, Chang-Sung; Lee, Desean; Ivey, Rasheed; Sinha-Hikim, Amiya P.

    2014-01-01

    Smoking is a major risk factor for diabetes, cardiovascular disease, and nonalcoholic fatty liver disease. The health risk associated with smoking can be exaggerated by obesity. We hypothesize that nicotine when combined with a high-fat diet (HFD) can also cause ectopic lipid accumulation in skeletal muscle, similar to recently observed hepatic steatosis. Adult C57BL6 male mice were fed a normal chow diet or HFD and received twice-daily ip injections of nicotine (0.75 mg/kg body weight) or sa...

  3. Enhanced susceptibility of cyclin kinase inhibitor p21 knockout mice to high fat diet induced atherosclerosis

    OpenAIRE

    Khanna Ashwani K

    2009-01-01

    Abstract Cyclin kinase inhibitor p21 is one of the most potent inhibitors of aortic smooth muscle cell proliferation, a key mediator of atherosclerosis. This study tests if p2l deficiency will result in severe atherosclerosis in a mouse model. p21-/- and strain matched wild type mice were fed with high fat diet for 21 weeks. Analysis for biochemical parameters (cholesterol, triglycerides) in serum and mRNA expression of CD36, HO-1, TGF-β, IFN-γ, TNF-α, PPAR-γ and NADPH oxidase components (p22...

  4. Effects of Silybum marianum Extract on High-Fat Diet Induced Metabolic Disorders in Rats

    OpenAIRE

    Sayin Fatma Kubra; Buyukbas Sadik; Basarali M. Kemal; Alp Harun; Toy Hatice; Ugurcu Veli

    2016-01-01

    Silybum marianum extract (SME) has been used for centuries as a natural remedy for diseases of liver and biliary tract. Lately, it has been promoted as a nutritional supplement for beneficial effects on some risk factors of diabetes and hyperlipidemia. In this study we aimed to determine the effects of SME on high-fat diet (HFD) induced metabolic disorders. Male Sprague Dawley rats were fed HFD for 11 weeks to induce obesity. SME was given to animals for two different durations, for 11 weeks ...

  5. Salvia libanotica improves glycemia and serum lipid profile in rats fed a high fat diet

    OpenAIRE

    Bassil, Maya; Costantine F. Daher; Mroueh, Mohammad; Zeeni, Nadine

    2015-01-01

    Background Salvia libanotica (S. Libanotica) is a commonly used herb in folk medicine in Lebanon and the Middle East. The present study aimed to assess the scientific basis for the therapeutic use of S. libanotica in glycemia and to evaluate its effects on lipemia and abdominal fat. Methods Animals were fed a high-fat diet and allocated into a control and three experimental groups (GI, GII and GIII) receiving incremental doses of the plant water extract in drinking water (50, 150 and 450 mg/K...

  6. Effects on Bacterial Translocation of High-Fat Enteral Nutrition in Bile Duct Ligated Rats

    OpenAIRE

    Nihat Zafer Utkan; Tufan Elipek

    2012-01-01

    Objective: Bacterial Translocation (BT) from the gastrointestinal system is at the center of current sepsis theories. In patients with obstructive jaundice, the absence of intraluminal bile flow causes some alterations and mucosal damage in the gut. In the present study, it was aimed to investigate the effects on BT of high-fat enteral nutrition in bile duct ligated rats.Material and Methods: In this study, a total of 28 healthy Spraque-Dawley rats, weighing 230-300 gr, were grouped into fou...

  7. Effect of a high fat diet on a mouse model of Alzheimer's disease

    OpenAIRE

    Knight, Elysse

    2011-01-01

    THE UNIVERSITY OF MANCHESTER Abstract of thesis Submitted by Elysse Knight for the degree of Doctor of Philosophy and entitled Effect of a high fat diet on a mouse model of Alzheimer’s disease, December 2010. Alzheimer’s disease (AD) is a progressive neurodegenerative disorder, characterised by deficits in language, behaviour and memory. Increasing evidence suggests that mid-life obesity and a diet high in fat are risk factors for AD. In contrast, life-threatening weight loss occurs and wor...

  8. Intake of high-fat diet stimulates the risk of ultraviolet radiation-induced skin tumors and malignant progression of papillomas to carcinoma in SKH-1 hairless mice

    Energy Technology Data Exchange (ETDEWEB)

    Vaid, Mudit; Singh, Tripti; Prasad, Ram [Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Katiyar, Santosh K., E-mail: skatiyar@uab.edu [Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Birmingham Veterans Affairs Medical Center, Birmingham, AL 35294 (United States)

    2014-01-01

    Previously, we showed that administration of a high-fat diet (HF-diet) to C57BL/6 mice exacerbates their response to short-term UVB radiation-induced inflammation in the skin. To explore the effects of an HF-diet on UVB-induced tumorigenesis, we have used the SKH-1 hairless mouse model in which the mice are exposed to UVB radiation (180 mJ/cm{sup 2}) three times a week for 24 weeks. The development of UVB-induced skin tumors was rapid and the tumor multiplicity and tumor size were significantly higher (P < 0.01–0.005) in the mice fed an HF-diet than the mice fed a control-diet (C-diet). Moreover, the malignant progression of UVB-induced papillomas to carcinomas was higher in HF-diet-fed mice. On analysis of tumors and tumor-uninvolved skin samples from the tumor-bearing mice, we found that administration of an HF-diet significantly enhanced the levels of UVB-induced expression of cyclooxygenase-2 (COX-2), prostaglandin E{sub 2} (P < 0.01), and PGE{sub 2} receptors, and activation of NF-κB in the UVB-exposed skin as well as in tumors. In addition the HF-diet enhanced the expression of proinflammatory cytokines, including tumor necrosis factor-α (P < 0.01), interleukin (IL)-1β (P < 0.01) and IL-6 (P < 0.05) in the UVB-exposed skin as well as in tumors. Western blot analysis revealed that HF-diet enhanced the levels of epidermal cell proliferation, phosphatidylinositol 3-kinase and phosphorylation of Akt at Ser{sup 473} in UVB-exposed skin and skin tumors. Collectively, these data demonstrate that the regular consumption of an HF-diet increases the risk of photocarcinogenesis in mice and that this is associated with enhanced expression of inflammatory mediators in the UVB-exposed skin and tumors. - Highlights: • Consumption of high-fat diet increases UVB-induced skin tumor development in mice. • Intake of high-fat diet stimulates progression of UV-induced papilloma to carcinoma. • Intake of high-fat diet enhances inflammation in UV-exposed skin • Regular

  9. Coenzyme Q Metabolism Is Disturbed in High Fat Diet-Induced Non Alcoholic Fatty Liver Disease in Rats

    Directory of Open Access Journals (Sweden)

    Kathleen M Botham

    2012-02-01

    Full Text Available Oxidative stress is believed to be a major contributory factor in the development of non alcoholic fatty liver disease (NAFLD, the most common liver disorder worldwide. In this study, the effects of high fat diet-induced NAFLD on Coenzyme Q (CoQ metabolism and plasma oxidative stress markers in rats were investigated. Rats were fed a standard low fat diet (control or a high fat diet (57% metabolizable energy as fat for 18 weeks. The concentrations of total (reduced + oxidized CoQ9 were increased by > 2 fold in the plasma of animals fed the high fat diet, while those of total CoQ10 were unchanged. Reduced CoQ levels were raised, but oxidized CoQ levels were not, thus the proportion in the reduced form was increased by about 75%. A higher percentage of plasma CoQ9 as compared to CoQ10 was in the reduced form in both control and high fat fed rats. Plasma protein thiol (SH levels were decreased in the high fat-fed rats as compared to the control group, but concentrations of lipid hydroperoxides and low density lipoprotein (LDL conjugated dienes were unchanged. These results indicate that high fat diet-induced NAFLD in rats is associated with altered CoQ metabolism and increased protein, but not lipid, oxidative stress.

  10. Effect of fermented soybean product (Cheonggukjang) intake on metabolic parameters in mice fed a high-fat diet.

    Science.gov (United States)

    Kim, Jiyoung; Choi, Jung Nam; Choi, Joo Hee; Cha, Youn Soo; Muthaiya, Maria John; Lee, Choong Hwan

    2013-10-01

    As a nontargeted metabolomics approach, we investigated changes in the plasma metabolite levels in a mouse model of obesity induced by a high-fat diet and fermented soybean product diet. We analyzed the plasma samples by using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). In the present study, the animals were divided into four groups according to the diet type; normal fat diet control group (ND), high-fat diet control group (HD), high-fat diet plus 30% cooked soybean power (HD + S), and high-fat diet plus 30% 72-h fermented Cheonggukjang powder (HD + CGJ). To examine the changes in plasma metabolite levels because of high-fat diet feeding, total cholesterol and triglyceride levels were measured. Total cholesterol and triglyceride levels were lower in the HD + S and HD + CGJ groups than in the ND group. According to partial least-squares discriminant analysis (PLS-DA), major metabolites contributing to the discrimination between each group were assigned as lipid metabolites in plasma, e.g., lyso-phosphatidylcholines and phosphatidylcholines. Therefore, diets containing soy-based food products, which are rich sources of isoflavonoids, might be helpful for controlling the lipid metabolism under high-fat diet conditions. PMID:23609950

  11. Anti-obesity potential of enzymatic fragments of hyaluronan on high-fat diet-induced obesity in C57BL/6 mice.

    Science.gov (United States)

    Park, Byong-Gon; Park, Yoon-Sun; Park, Joo Woong; Shin, Eunji; Shin, Woon-Seob

    2016-04-22

    Hyaluronan has diverse biological activities depending on its molecular size. The hyaluronan fragments (50 kDa) can decrease adipogenic differentiation in vitro. However, in vivo anti-obesitic effects of hyaluronan fragments have not been elucidated. Therefore, we examined the anti-obesity effects of hyaluronan fragments on high-fat diet induced obesity in C57BL/6 mice. Oral administration of hyaluronan fragments (200 mg/kg for 8 weeks) decreased body weight, adipose tissues, serum lipid (low-density lipoprotein cholesterol, triglyceride), and leptin level. Hyaluronan fragments decreased the hypertrophy of adipose tissue and ameliorated liver steatosis. The mRNA expression of leptin was reduced in adipocyte by treatment with hyaluronan fragments. Additionally, hyaluronan fragments enhanced the mRNA expression of PPAR-α and its target genes UCP-2 and decreased mRNA expression of PPAR- γ and fatty acid synthase in liver. In conclusions, hyaluronan fragments had marked effects on inhibiting the development of obesity in obese mice fed the high-fat diet. It suggested that enhancing PPAR-α and suppressing PPAR-γ expression are two possible mechanisms for the anti-obesitic effect of hyaluronan fragments. PMID:27012203

  12. Effects of Berberine on Amelioration of Hyperglycemia and Oxidative Stress in High Glucose and High Fat Diet-Induced Diabetic Hamsters In Vivo

    Directory of Open Access Journals (Sweden)

    Cong Liu

    2015-01-01

    Full Text Available This study investigated the effects of berberine on amelioration of hyperglycemia and hyperlipidemia and the mechanism involved in high glucose and high fat diet-induced diabetic hamsters. Golden hamsters fed with high glucose and high fat diet were medicated with metformin, simvastatin, and low or high dose of berberine (50 and 100 mg·kg−1 for 6 weeks. The results showed that the body weights were significantly lower in berberine-treated groups than control group. Histological analyses revealed that the treatment of berberine inhibited hepatic fat accumulation. Berberine significantly reduced plasma total cholesterol, triglyceride, free fatty acid, low density lipoprotein cholesterol, malondialdehyde, thiobarbituric acid-reactive substance, and 8-isoprostane level but significantly increased plasma superoxide dismutase activity. Glucose and insulin levels were significantly reduced in metformin and berberine-treated groups. Glucose tolerance tests documented that berberine-treated mice were more glucose tolerant. Berberine treatment increased expression of skeletal muscle glucose transporter 4 mRNA and significantly decreased liver low density lipoprotein receptor mRNA expression. The study suggested that berberine was effective in lowering blood glucose and lipids levels, reducing the body weight, and alleviating the oxidative stress in diabetic hamsters, which might be beneficial in reducing the cardiovascular risk factors in diabetes.

  13. Effect of Regular Exercise on the Histochemical Changes of d-Galactose-Induced Oxidative Renal Injury in High-Fat Diet-Fed Rats

    International Nuclear Information System (INIS)

    Renal lipid accumulation exhibits slowly developing chronic kidney disease and is associated with increased oxidative stress. The impact of exercise on the obese- and oxidative stress-related renal disease is not well understood. The purpose of this study was to investigate whether a high-fat diet (HFD) would accelerate d-galactose-induced aging process in rat kidney and to examine the preventive effect of regular exercise on the obese- and oxidative stress-related renal disease. Oxidative stress was induced by an administration of d-galactose (100 mg/kg intraperitoneally injected) for 9 weeks, and d-galactose-treated rats were also fed with a high-fat diet (60% kcal as fat) for 9 weeks to induce obesity. We investigated the efficacy of regular exercise in reducing renal injury by analyzing Nε-carboxymethyllysine (CML), 8-hydroxygluanine (8-OHdG) and apoptosis. When rats were fed with a HFD for 9 weeks in d-galactose-treated rats, an increased CML accumulation, oxidative DNA damage and renal podocyte loss were observed in renal glomerular cells and tubular epithelial cells. However, the regular exercise restored all these renal changes in HFD plus d-galactose-treated rats. Our data suggested that long-term HFD may accelerate the deposition of lipoxidation adducts and oxidative renal injury in d-galactose-treated rats. The regular exercise protects against obese- and oxidative stress-related renal injury by inhibiting this lipoxidation burden

  14. Stevioside ameliorates high-fat diet-induced insulin resistance and adipose tissue inflammation by downregulating the NF-κB pathway

    International Nuclear Information System (INIS)

    Highlights: ► Stevioside ameliorates high-fat diet-induced insulin resistance. ► Stevioside alleviates the adipose tissue inflammation. ► Stevioside reduces macrophages infiltration into the adipose tissue. ► Stevioside suppresses the activation of NF-κB in the adipose tissue. -- Abstract: Accumulating evidence suggests that adipose tissue is the main source of pro-inflammatory molecules that predispose individuals to insulin resistance. Stevioside (SVS) is a widely used sweetener with multiple beneficial effects for diabetic patients. In this study, we investigated the effect of SVS on insulin resistance and the pro-inflammatory state of adipose tissue in mice fed with a high-fat diet (HFD). Oral administration of SVS for 1 month had no effect on body weight, but it significantly improved fasting glucose, basal insulin levels, glucose tolerance and whole body insulin sensitivity. Interestingly, these changes were accompanied with decreased expression levels of several inflammatory cytokines in adipose tissue, including TNF-α, IL6, IL10, IL1β, KC, MIP-1α, CD11b and CD14. Moreover, macrophage infiltration in adipose tissue was remarkably reduced by SVS. Finally, SVS significantly suppressed the nuclear factor-kappa b (NF-κB) signaling pathway in adipose tissue. Collectively, these results suggested that SVS may ameliorate insulin resistance in HFD-fed mice by attenuating adipose tissue inflammation and inhibiting the NF-κB pathway.

  15. Stevioside ameliorates high-fat diet-induced insulin resistance and adipose tissue inflammation by downregulating the NF-{kappa}B pathway

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhiquan; Xue, Liqiong; Guo, Cuicui; Han, Bing; Pan, Chunming; Zhao, Shuangxia; Song, Huaidong [State Key Laboratory of Medical Genomics, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Ma, Qinyun, E-mail: qinyunma@126.com [State Key Laboratory of Medical Genomics, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China)

    2012-01-27

    Highlights: Black-Right-Pointing-Pointer Stevioside ameliorates high-fat diet-induced insulin resistance. Black-Right-Pointing-Pointer Stevioside alleviates the adipose tissue inflammation. Black-Right-Pointing-Pointer Stevioside reduces macrophages infiltration into the adipose tissue. Black-Right-Pointing-Pointer Stevioside suppresses the activation of NF-{kappa}B in the adipose tissue. -- Abstract: Accumulating evidence suggests that adipose tissue is the main source of pro-inflammatory molecules that predispose individuals to insulin resistance. Stevioside (SVS) is a widely used sweetener with multiple beneficial effects for diabetic patients. In this study, we investigated the effect of SVS on insulin resistance and the pro-inflammatory state of adipose tissue in mice fed with a high-fat diet (HFD). Oral administration of SVS for 1 month had no effect on body weight, but it significantly improved fasting glucose, basal insulin levels, glucose tolerance and whole body insulin sensitivity. Interestingly, these changes were accompanied with decreased expression levels of several inflammatory cytokines in adipose tissue, including TNF-{alpha}, IL6, IL10, IL1{beta}, KC, MIP-1{alpha}, CD11b and CD14. Moreover, macrophage infiltration in adipose tissue was remarkably reduced by SVS. Finally, SVS significantly suppressed the nuclear factor-kappa b (NF-{kappa}B) signaling pathway in adipose tissue. Collectively, these results suggested that SVS may ameliorate insulin resistance in HFD-fed mice by attenuating adipose tissue inflammation and inhibiting the NF-{kappa}B pathway.

  16. Lipopolysaccharide Inhibits the Channel Activity of the P2X7 Receptor

    Directory of Open Access Journals (Sweden)

    Elias Leiva-Salcedo

    2011-01-01

    Full Text Available The purinergic P2X7 receptor (P2X7R plays an important role during the immune response, participating in several events such as cytokine release, apoptosis, and necrosis. The bacterial endotoxin lipopolysaccharide (LPS is one of the strongest stimuli of the immune response, and it has been shown that P2X7R activation can modulate LPS-induced responses. Moreover, a C-terminal binding site for LPS has been proposed. In order to evaluate if LPS can directly modulate the activity of the P2X7R, we tested several signaling pathways associated with P2X7R activation in HEK293 cells that do not express the TLR-4 receptor. We found that LPS alone was unable to induce any P2X7R-related activity, suggesting that the P2X7R is not directly activated by the endotoxin. On the other hand, preapplication of LPS inhibited ATP-induced currents, intracellular calcium increase, and ethidium bromide uptake and had no effect on ERK activation in HEK293 cells. In splenocytes-derived T-regulatory cells, in which ATP-induced apoptosis is driven by the P2X7R, LPS inhibited ATP-induced apoptosis. Altogether, these results demonstrate that LPS modulates the activity of the P2X7R and suggest that this effect could be of physiological relevance.

  17. Lipopolysaccharide Inhibits the Channel Activity of the P2X7 Receptor

    Science.gov (United States)

    Leiva-Salcedo, Elias; Coddou, Claudio; Rodríguez, Felipe E.; Penna, Antonello; Lopez, Ximena; Neira, Tanya; Fernández, Ricardo; Imarai, Mónica; Rios, Miguel; Escobar, Jorge; Montoya, Margarita; Huidobro-Toro, J. Pablo; Escobar, Alejandro; Acuña-Castillo, Claudio

    2011-01-01

    The purinergic P2X7 receptor (P2X7R) plays an important role during the immune response, participating in several events such as cytokine release, apoptosis, and necrosis. The bacterial endotoxin lipopolysaccharide (LPS) is one of the strongest stimuli of the immune response, and it has been shown that P2X7R activation can modulate LPS-induced responses. Moreover, a C-terminal binding site for LPS has been proposed. In order to evaluate if LPS can directly modulate the activity of the P2X7R, we tested several signaling pathways associated with P2X7R activation in HEK293 cells that do not express the TLR-4 receptor. We found that LPS alone was unable to induce any P2X7R-related activity, suggesting that the P2X7R is not directly activated by the endotoxin. On the other hand, preapplication of LPS inhibited ATP-induced currents, intracellular calcium increase, and ethidium bromide uptake and had no effect on ERK activation in HEK293 cells. In splenocytes-derived T-regulatory cells, in which ATP-induced apoptosis is driven by the P2X7R, LPS inhibited ATP-induced apoptosis. Altogether, these results demonstrate that LPS modulates the activity of the P2X7R and suggest that this effect could be of physiological relevance. PMID:21941410

  18. High-Fat Programming of Hyperglycemia, Hyperinsulinemia, Insulin Resistance, Hyperleptinemia, and Altered Islet Architecture in 3-Month-Old Wistar Rats

    OpenAIRE

    Cerf, Marlon E.; Chapman, Charna S.; Louw, Johan

    2012-01-01

    High-fat programming, by exposure to a high-saturated-fat diet in utero and/or during lactation, compromises beta-cell development and function in neonatal and weanling offspring. Therefore, high-fat programming effects were investigated on metabolism and islet architecture in young adult rats. Three-month-old male and female Wistar rat offspring were studied: HFG (maintained on a high-fat diet throughout fetal life), HFP (high-fat diet maintenance from birth to 3 months), and HFGP (high-fat ...

  19. Bardoxolone Methyl Prevents Mesenteric Fat Deposition and Inflammation in High-Fat Diet Mice

    Science.gov (United States)

    Dinh, Chi H. L.; Szabo, Alexander; Yu, Yinghua; Camer, Danielle; Wang, Hongqin; Huang, Xu-Feng

    2015-01-01

    Mesenteric fat belongs to visceral fat. An increased deposition of mesenteric fat contributes to obesity associated complications such as type 2 diabetes and cardiovascular diseases. We have investigated the therapeutic effects of bardoxolone methyl (BARD) on mesenteric adipose tissue of mice fed a high-fat diet (HFD). Male C57BL/6J mice were administered oral BARD during HFD feeding (HFD/BARD), only fed a high-fat diet (HFD), or fed low-fat diet (LFD) for 21 weeks. Histology and immunohistochemistry were used to analyse mesenteric morphology and macrophages, while Western blot was used to assess the expression of inflammatory, oxidative stress, and energy expenditure proteins. Supplementation of drinking water with BARD prevented mesenteric fat deposition, as determined by a reduction in large adipocytes. BARD prevented inflammation as there were fewer inflammatory macrophages and reduced proinflammatory cytokines (interleukin-1 beta and tumour necrosis factor alpha). BARD reduced the activation of extracellular signal-regulated kinase (ERK) and Akt, suggesting an antioxidative stress effect. BARD upregulates energy expenditure proteins, judged by the increased activity of tyrosine hydroxylase (TH) and AMP-activated protein kinase (AMPK) and increased peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), and uncoupling protein 2 (UCP2) proteins. Overall, BARD induces preventive effect in HFD mice through regulation of mesenteric adipose tissue. PMID:26618193

  20. Liking for high fat foods in patients with Obstructive Sleep Apnoea.

    Science.gov (United States)

    Smith, Simon S; Waight, Catherine; Doyle, Geoffrey; Rossa, Kalina R; Sullivan, Karen A

    2014-07-01

    Excess weight and obesity are factors that are strongly associated with risk for Obstructive Sleep Apnoea (OSA). Weight loss has been associated with improvements in clinical indicators of OSA severity; however, patients' beliefs about diet change have not been investigated. This study utilized a validated behaviour change model to estimate the relationship between food liking, food intake and indices of OSA severity. Two-hundred and six OSA patients recruited from a Sleep Disorders Clinic completed standardized questionnaires of: a) fat and fibre food intake, food liking, and food knowledge and; b) attitudes and intentions towards fat reduction. OSA severity and body mass index (BMI) were objectively measured using standard clinical guidelines. The relationship between liking for high fat food and OSA severity was tested with hierarchical regression. Gender and BMI explained a significant 20% of the variance in OSA severity, Fibre Liking accounted for an additional 6% (a negative relationship), and Fat Liking accounted for a further 3.6% of variance. Although the majority of individuals (47%) were currently "active" in reducing fat intake, overall the patients' dietary beliefs and behaviours did not correspond. The independent relationship between OSA severity and liking for high fat foods (and disliking of high fibre foods) may be consistent with a two-way interaction between sleep disruption and food choice. Whilst the majority of OSA patients were intentionally active in changing to a healthy diet, further emphasis on improving healthy eating practices and beliefs in this population is necessary. PMID:24699392

  1. Whey protein reduces early life weight gain in mice fed a high-fat diet

    DEFF Research Database (Denmark)

    Tranberg, Britt; Hellgren, Lars; Lykkesfeldt, Jens; Sejrsen, Kristen; Jeamet, Aymeric; Rune, Ida; Ellekilde, Merete; Nielsen, Dennis Sandris; Hansen, Axel Kornerup

    2013-01-01

    An increasing number of studies indicate that dairy products, including whey protein, alleviate several disorders of the metabolic syndrome. Here, we investigated the effects of whey protein isolate (whey) in mice fed a high-fat diet hypothesising that the metabolic effects of whey would be...... associated with changes in the gut microbiota composition. Five-week-old male C57BL/6 mice were fed a high-fat diet ad libitum for 14 weeks with the protein source being either whey or casein. Faeces were collected at week 0, 7, and 13 and the fecal microbiota was analysed by denaturing gradient gel...... weight gain was similar resulting in a 15% lower final body weight in the whey group relative to casein (34.0±1.0 g vs. 40.2±1.3 g, P<0.001). Food intake was unaffected by protein source throughout the study period. Fasting insulin was lower in the whey group (P<0.01) and glucose clearance was improved...

  2. Bardoxolone Methyl Prevents Mesenteric Fat Deposition and Inflammation in High-Fat Diet Mice

    Directory of Open Access Journals (Sweden)

    Chi H. L. Dinh

    2015-01-01

    Full Text Available Mesenteric fat belongs to visceral fat. An increased deposition of mesenteric fat contributes to obesity associated complications such as type 2 diabetes and cardiovascular diseases. We have investigated the therapeutic effects of bardoxolone methyl (BARD on mesenteric adipose tissue of mice fed a high-fat diet (HFD. Male C57BL/6J mice were administered oral BARD during HFD feeding (HFD/BARD, only fed a high-fat diet (HFD, or fed low-fat diet (LFD for 21 weeks. Histology and immunohistochemistry were used to analyse mesenteric morphology and macrophages, while Western blot was used to assess the expression of inflammatory, oxidative stress, and energy expenditure proteins. Supplementation of drinking water with BARD prevented mesenteric fat deposition, as determined by a reduction in large adipocytes. BARD prevented inflammation as there were fewer inflammatory macrophages and reduced proinflammatory cytokines (interleukin-1 beta and tumour necrosis factor alpha. BARD reduced the activation of extracellular signal-regulated kinase (ERK and Akt, suggesting an antioxidative stress effect. BARD upregulates energy expenditure proteins, judged by the increased activity of tyrosine hydroxylase (TH and AMP-activated protein kinase (AMPK and increased peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α, and uncoupling protein 2 (UCP2 proteins. Overall, BARD induces preventive effect in HFD mice through regulation of mesenteric adipose tissue.

  3. Antihyperlipidemic Effects of Sesamum indicum L. in Rabbits Fed a High-Fat Diet

    Directory of Open Access Journals (Sweden)

    Sedigheh Asgary

    2013-01-01

    Full Text Available The present study aimed to investigate the anti-hyperlipidemic effects of sesame in a high-fat fed rabbit model. Animals were randomly divided into four groups of eight animals each for 60 days as follows: normal diet, hypercholesterolemic diet (1% cholesterol, hypercholesterolemic diet (1% cholesterol + sesame seed (10%, and hypercholesterolemic diet (1% cholesterol + sesame oil (5%. Serum concentrations of total cholesterol, LDL-C, HDL-C, triglycerides, apoA and apoB, SGOT, SGPT, glucose and insulin were measured at the end of supplementation period in all studied groups. Hypercholesterolemic feeding resulted in a significant elevation of TC, TG, LDL-C, HDL-C, SGOT and SGPT as compared to the normocholesterolemic diet group (P0.05. In contrast, rabbits supplemented with sesame oil were found to have lower circulating concentrations of TC, LDL-C, HDL-C, SGOT and SGPT (P0.05. Supplementation with sesame oil, but not sesame seed, can ameliorate serum levels of lipids and hepatic enzymes in rabbits under a high-fat diet.

  4. Arctigenin, a Potential Anti-Arrhythmic Agent, Inhibits Aconitine-Induced Arrhythmia by Regulating Multi-Ion Channels

    Directory of Open Access Journals (Sweden)

    Zhenying Zhao

    2013-11-01

    Full Text Available Background/Aims: Arctigenin possesses biological activities, but its underlying mechanisms at the cellular and ion channel levels are not completely understood. Therefore, the present study was designed to identify the anti-arrhythmia effect of arctigenin in vivo, as well as its cellular targets and mechanisms. Methods: A rat arrhythmia model was established via continuous aconitine infusion, and the onset times of ventricular premature contraction, ventricular tachycardia and death were recorded. The Action Potential Duration (APD, sodium current (INa, L-type calcium current (ICa, L and transient outward potassium current (Ito were measured and analysed using a patch-clamp recording technique in normal rat cardiomyocytes and myocytes of arrhythmia aconitine-induced by. Results: Arctigenin significantly delayed the arrhythmia onset in the aconitine-induced rat model. The 50% and 90% repolarisations (APD50 and APD90 were shortened by 100 µM arctigenin; the arctigenin dose also inhibited the prolongation of APD50 and APD90 caused by 1 µM aconitine. Arctigenin inhibited INa and ICa,L and attenuated the aconitine-increased INa and ICa,L by accelerating the activation process and delaying the inactivation process. Arctigenin enhanced Ito by facilitating the activation process and delaying the inactivation process, and recoverd the decreased Ito induced by aconitine. Conclusions: Arctigenin has displayed anti-arrhythmia effects, both in vivo and in vitro. In the context of electrophysiology, INa, ICa, L, and Ito may be multiple targets of arctigenin, leading to its antiarrhythmic effect.

  5. Sulfonation of 17β-estradiol and inhibition of sulfotransferase activity by polychlorobiphenylols and celecoxib in channel catfish, Ictalurus punctatus

    International Nuclear Information System (INIS)

    The sulfonation of 17β-estradiol (E2) by human liver and recombinant sulfotransferases is influenced by environmental contaminants such as hydroxylated metabolites of polychlorinated biphenyls (OH-PCBs), which are potent inhibitors, and the therapeutic drug, celecoxib, which affects positional sulfonation of E2. In some locations, the aquatic environment is contaminated by PCBs, OH-PCBs and widely used therapeutic drugs. The objectives of this study were to investigate the sulfonation kinetics of E2 in liver cytosol from channel catfish (Ictalurus punctatus); to examine the effect of OH-PCBs on E2 sulfonation; and to determine if celecoxib altered the position of E2 sulfonation, as it does with human liver cytosol. E2 was converted to both 3- and 17-sulfates by catfish liver cytosol. At E2 concentrations below 1μM, formation of E2-3-sulfate (E2-3-S) predominated, but substrate inhibition was observed at higher concentrations. Rates of E2-3-S formation at different E2 concentrations were fit to a substrate inhibition model, with K'm and V'max values of 0.40+/-0.10μM and 91.0+/-4.7pmol/min/mg protein, respectively and Ki of 1.08+/-0.09μM. The formation of E2-17-S fit Michaelis-Menten kinetics over the concentration range 25nM to 2.5μM, with Km and Vmax values of 1.07+/-0.23μM and 25.7+/-4.43pmol/min/mg protein, respectively. The efficiency (Vmax/Km) of formation of E2-3-S was 9.8-fold higher than that of E2-17-S. Several OH-PCBs inhibited E2 3-sulfonation, measured at an E2 concentration of 1nM. Of those tested, the most potent inhibitor was 4'-OH-CB79, with two chlorine atoms flanking the OH group (IC50: 94nM). The inhibition of estrogen sulfonation by OH-PCBs may disrupt the endocrine system and thus contribute to the known toxic effects of these compounds. Celecoxib did not stimulate E2-17-S formation, as is the case with human liver cytosol, but did inhibit the formation of E2-3-S (IC50: 44μM) and to a lesser extent, E2-17-S (IC50: >160μM), suggesting the

  6. FM1-43 is a permeant blocker of mechanosensitive ion channels in sensory neurons and inhibits behavioural responses to mechanical stimuli

    Directory of Open Access Journals (Sweden)

    Drew Liam J

    2007-01-01

    Full Text Available Abstract The molecular identity and pharmacological properties of mechanically gated ion channels in sensory neurons are poorly understood. We show that FM1-43, a styryl dye used to fluorescently label cell membranes, permeates mechanosensitive ion channels in cultured dorsal root ganglion neurons, resulting in blockade of three previously defined subtypes of mechanically activated currents. Blockade and dye uptake is voltage dependent and regulated by external Ca2+. The structurally related larger dye FM3-25 inhibited mechanically activated currents to a lesser degree and did not permeate the channels. In vivo, FMI-43 decreases pain sensitivity in the Randall-Selitto test and increases the withdrawal threshold from von Frey hairs, together suggesting that the channels expressed at the cell body in culture mediate mechanosensation in the intact animal. These data give further insight into the mechanosensitive ion channels expressed by somatosensory neurons and suggest FM dyes are an interesting tool for studying them.

  7. Inhibition of cell proliferation by a selective inhibitor of the Ca2+-activated Cl− channel, Ano1

    International Nuclear Information System (INIS)

    Highlights: ► T16Ainh-A01 blocked Ano1 currents in HEK cells expressing Ano1. ► T16Ainh-A01 reduced proliferation in ICC primary cultures and CFPAC-1 cell line. ► T16Ainh-A01 reduced proliferation of ICC in intact smooth muscle strips. -- Abstract: Background: Ion channels play important roles in regulation of cellular proliferation. Ano1 (TMEM16A) is a Ca2+-activated Cl− channel expressed in several tumors and cell types. In the muscle layers of the gastrointestinal tract Ano1 is selectively expressed in interstitial cells of Cajal (ICC) and appears to be required for normal gastrointestinal slow wave electrical activity. However, Ano1 is expressed in all classes of ICC, including those that do not generate slow waves suggesting that Ano1 may have other functions. Indeed, a role for Ano1 in regulating proliferation of tumors and ICC has been recently suggested. Recently, a high-throughput screen identified a small molecule, T16Ainh-A01 as a specific inhibitor of Ano1. Aim: To investigate the effect of the T16Ainh-A01 inhibitor on proliferation in ICC and in the Ano1-expressing human pancreatic cancer cell line CFPAC-1. Methods: Inhibition of Ano1 was demonstrated by whole cell voltage clamp recordings of currents in cells transfected with full-length human Ano1. The effect of T16Ainh-A01 on ICC proliferation was examined in situ in organotypic cultures of intact mouse small intestinal smooth muscle strips and in primary cell cultures prepared from these tissues. ICC were identified by Kit immunoreactivity. Proliferating ICC and CFPAC-1 cells were identified by immunoreactivity for the nuclear antigen Ki67 or EdU incorporation, respectively. Results: T16Ainh-A01 inhibited Ca2+-activated Cl− currents by 60% at 10 μM in a voltage-independent fashion. Proliferation of ICC was significantly reduced in primary cultures from BALB/c mice following treatment with T16Ainh-A01. Proliferation of the CFPAC-1 human cell-line was also reduced by T16Ainh-A01. In

  8. The calmodulin inhibitor CGS 9343B inhibits voltage-dependent K{sup +} channels in rabbit coronary arterial smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hongliang; Hong, Da Hye; Kim, Han Sol; Kim, Hye Won [Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, 200-701 (Korea, Republic of); Jung, Won-Kyo [Department of Biomedical Engineering, Center for Marine-Integrated Biomedical Technology (BK21 Plus), Pukyong National University, Busan 608-737 (Korea, Republic of); Na, Sung Hun [Institute of Medical Sciences, Department of Obstetrics and Gynecology, Kangwon National University Hospital, School of Medicine, Kangwon National University, Chuncheon, 200-701 (Korea, Republic of); Jung, In Duk; Park, Yeong-Min [Department of Immunology, Lab of Dendritic Cell Differentiation and Regulation, College of Medicine, Konkuk University, Chungju 380-701 (Korea, Republic of); Choi, Il-Whan, E-mail: cihima@inje.ac.kr [Department of Microbiology, Inje University College of Medicine, Busan, 614-735 (Korea, Republic of); Park, Won Sun, E-mail: parkws@kangwon.ac.kr [Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, 200-701 (Korea, Republic of)

    2015-06-15

    We investigated the effects of the calmodulin inhibitor CGS 9343B on voltage-dependent K{sup +} (Kv) channels using whole-cell patch clamp technique in freshly isolated rabbit coronary arterial smooth muscle cells. CGS 9343B inhibited Kv currents in a concentration-dependent manner, with a half-maximal inhibitory concentration (IC{sub 50}) value of 0.81 μM. The decay rate of Kv channel inactivation was accelerated by CGS 9343B. The rate constants of association and dissociation for CGS 9343B were 2.77 ± 0.04 μM{sup −1} s{sup −1} and 2.55 ± 1.50 s{sup −1}, respectively. CGS 9343B did not affect the steady-state activation curve, but shifted the inactivation curve toward to a more negative potential. Train pulses (1 or 2 Hz) application progressively increased the CGS 9343B-induced Kv channel inhibition. In addition, the inactivation recovery time constant was increased in the presence of CGS 9343B, suggesting that CGS 9343B-induced inhibition of Kv channel was use-dependent. Another calmodulin inhibitor, W-13, did not affect Kv currents, and did not change the inhibitory effect of CGS 9343B on Kv current. Our results demonstrated that CGS 9343B inhibited Kv currents in a state-, time-, and use-dependent manner, independent of calmodulin inhibition. - Highlights: • We investigated the effects of CGS 9394B on Kv channels. • CGS 9394B inhibited Kv current in a state-, time-, and use-dependent manner. • Caution is required when using CGS 9394B in vascular function studies.

  9. A high fat diet alters metabolic and bioenergetic function in the brain: A magnetic resonance spectroscopy study.

    Science.gov (United States)

    Raider, Kayla; Ma, Delin; Harris, Janna L; Fuentes, Isabella; Rogers, Robert S; Wheatley, Joshua L; Geiger, Paige C; Yeh, Hung-Wen; Choi, In-Young; Brooks, William M; Stanford, John A

    2016-07-01

    Diet-induced obesity and associated metabolic effects can lead to neurological dysfunction and increase the risk of developing Alzheimer's disease (AD) and Parkinson's disease (PD). Despite these risks, the effects of a high-fat diet on the central nervous system are not well understood. To better understand the mechanisms underlying the effects of high fat consumption on brain regions affected by AD and PD, we used proton magnetic resonance spectroscopy ((1)H-MRS) to measure neurochemicals in the hippocampus and striatum of rats fed a high fat diet vs. normal low fat chow. We detected lower concentrations of total creatine (tCr) and a lower glutamate-to-glutamine ratio in the hippocampus of high fat rats. Additional effects observed in the hippocampus of high fat rats included higher N-acetylaspartylglutamic acid (NAAG), and lower myo-inositol (mIns) and serine (Ser) concentrations. Post-mortem tissue analyses revealed lower phosphorylated AMP-activated protein kinase (pAMPK) in the striatum but not in the hippocampus of high fat rats. Hippocampal pAMPK levels correlated significantly with tCr, aspartate (Asp), phosphoethanolamine (PE), and taurine (Tau), indicating beneficial effects of AMPK activation on brain metabolic and energetic function, membrane turnover, and edema. A negative correlation between pAMPK and glucose (Glc) indicates a detrimental effect of brain Glc on cellular energy response. Overall, these changes indicate alterations in neurotransmission and in metabolic and bioenergetic function in the hippocampus and in the striatum of rats fed a high fat diet. PMID:27125544

  10. Inhibitory effects of Leonurus sibiricus on weight gain after menopause in ovariectomized and high-fat diet-fed mice.

    Science.gov (United States)

    Kim, Jangseon; Kim, Mi Hye; Choi, You Yeon; Hong, Jongki; Yang, Woong Mo

    2016-07-01

    Leonurus sibiricus, also called motherwort, is a well-known functional food and medicinal herb. It has been known to possess beneficial properties for women's health, especially for aged women. Estrogen deficiency in the menopause could induce lipid metabolic abnormalities in body fat, resulting in obesity. In this study, the inhibitory effects of L. sibiricus on obesity after the menopause were investigated. Female C57BL/6 mice were ovariectomized and fed high-fat diet (HFD) for 12 weeks. Following an induction period, aqueous extracts of L. sibiricus (LS) were orally administrated for 6 weeks. The body, uterine, and visceral fat weights were measured immediately after the animals were killed. Histological analysis was performed to monitor fat and liver. Serum levels of glucose, triglyceride, total cholesterol, and LDL-cholesterol were evaluated. In addition, the expression of lipases was analyzed. Total body weight was significantly decreased by LS treatment. Histological changes in adipocyte size were shown along with a decrease of visceral fat weight in the LS-treated group. In addition, the fat infiltration of liver was reduced by LS administration. LS-treated mice experienced decreases of serum triglyceride, total cholesterol, and LDL-cholesterol levels. The expression of HSL and ATGL was significantly increased by LS treatment. These results suggest that LS could regulate the lipid metabolism via an increase of lipases expression in ovariectomized and HFD-fed mice. LS might be a novel candidate for a functional food to inhibit weight gain after the menopause. PMID:26899238

  11. Adiponectin stimulates autophagy and reduces oxidative stress to enhance insulin sensitivity during high-fat diet feeding in mice.

    Science.gov (United States)

    Liu, Ying; Palanivel, Rengasamy; Rai, Esther; Park, Min; Gabor, Tim V; Scheid, Michael P; Xu, Aimin; Sweeney, Gary

    2015-01-01

    Numerous studies have characterized the antidiabetic effects of adiponectin, yet the precise cellular mechanisms in skeletal muscle, in particular, changes in autophagy, require further clarification. In the current study, we used a high-fat diet (HFD) to induce obesity and insulin resistance in wild-type (WT) or adiponectin knockout (Ad-KO) mice with and without adiponectin replenishment. Temporal analysis of glucose tolerance and insulin sensitivity using hyperinsulinemic-euglycemic clamp and muscle insulin receptor substrate and Akt phosphorylation demonstrated exaggerated and more rapid HFD-induced insulin resistance in skeletal muscle of Ad-KO mice. Superoxide dismutase activity, the reduced glutathione-to-glutathione disulfide ratio, and lipid peroxidation indicated that HFD-induced oxidative stress was corrected by adiponectin. Gene array analysis implicated several antioxidant enzymes, including Gpxs, Prdx, Sod, and Nox4, in mediating this effect. Adiponectin also attenuated palmitate-induced reactive oxygen species production in cultured myotubes and improved insulin-stimulated glucose uptake in primary muscle cells. Increased LC3-II and decreased p62 expression suggested that HFD induced autophagy in muscle of WT mice; however, these changes were not observed in Ad-KO mice. Replenishing adiponectin in Ad-KO mice increased LC3-II and Beclin1 and decreased p62 protein levels, induced fibroblast growth factor-21 expression, and corrected HFD-induced decreases in LC3, Beclin1, and ULK1 gene expression. In vitro studies examining changes in phospho-ULK1 (Ser555), LC3-II, and lysosomal enzyme activity confirmed that adiponectin directly induced autophagic flux in cultured muscle cells in an AMPK-dependent manner. We overexpressed an inactive mutant of Atg5 to create an autophagy-deficient cell model, and together with pharmacological inhibition of autophagy, demonstrated reduced insulin sensitivity under these conditions. In summary, adiponectin stimulated

  12. Semen cassiae attenuates myocardial ischemia and reperfusion injury in high-fat diet streptozotocin-induced type 2 diabetic rats.

    Science.gov (United States)

    Fu, Feng; Tian, Fei; Zhou, Heping; Lv, Weifeng; Tie, Ru; Ji, Lele; Li, Rong; Shi, Zhenwei; Yu, Liming; Liang, Xiangyan; Xing, Wenjuan; Xing, Jinliang; Yu, Jun; Sun, Lijun; Zhu, Hailong; Zhang, Haifeng

    2014-01-01

    Obese patients with type 2 diabetes mellitus (T2DM), which is characterized by hyperglycemia, are liable to more severe myocardial infarction. Semen Cassiae is proven to reduce serum lipid levels. This study investigated whether the Semen Cassiae extract (SCE) reduces myocardial ischemia and reperfusion (MI/R) injury with or without diabetes and the underlying mechanisms. The high-fat diet-fed streptozotocin (HFD-STZ) rat model was created as a T2DM model. Normal and DM rats received SCE treatment orally (10 mg/kg/day) for one week. Subsequently these animals were subjected to MI/R. Compared with the normal animals, DM rats showed increased plasma total cholesterol (TC) and triacylglycerol (TG), and more severe MI/R injury and cardiac functional impairment. SCE treatment significantly reduced the plasma TC and TG, improved the instantaneous first derivation of left ventricle pressure and reduced infarct size, decreased plasma creatine kinase and lactate dehydrogenase levels, and apoptosis index at the end of reperfusion in diabetic rats. Moreover, SCE treatment increased the antiapoptotic protein Akt and ERK1/2 phosphorylation levels. Pretreatment with a PI3K inhibitor wortmannin or an ERK1/2 inhibitor PD98059 not only blocked Akt and ERK1/2 phosphorylation respectively, but also inhibited the cardioprotective effects of SCE. However, SCE treatment did not show any effects on the MI/R injury in the normal rats. Our data suggest that SCE effectively improves myocardial function and reduces MI/R-induced injury in diabetic but not normal animals, which is possibly attributed to the reduced TC/TG levels and the triggered cell survival signaling Akt and ERK1/2. PMID:24467537

  13. Polyphenol-rich blackcurrant extract exerts hypocholesterolaemic and hypoglycaemic effects in mice fed a diet containing high fat and cholesterol.

    Science.gov (United States)

    Benn, Tyler; Kim, Bohkyung; Park, Young-Ki; Yang, Yue; Pham, Tho X; Ku, Chai Siah; Farruggia, Callie; Harness, Ellen; Smyth, Joan A; Lee, Ji-Young

    2015-06-14

    Obesity is associated with an increased risk of metabolic abnormalities, such as hyperlipidaemia and hyperglycaemia. We investigated whether polyphenol-rich blackcurrant extract (BCE) can prevent high fat/high cholesterol (HF/HC) diet-induced metabolic disturbances in mice. Male C57BL/6J mice were fed a modified AIN-93M diet containing HF/HC (16% fat, 0·25% cholesterol, w/w) or the same diet supplemented with 0·1% BCE (w/w) for 12 weeks. There were no differences in total body weight and liver weight between groups. Plasma total cholesterol (TC) and glucose levels were significantly lower in BCE group than in controls, while plasma TAG levels were not significantly different. There was a decreasing trend in hepatic TAG levels, and histological evaluation of steatosis grade was markedly lower in the livers of mice fed BCE. Although the mRNA levels of major regulators of hepatic cholesterol metabolism, i.e. 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGR) and LDL receptor (LDLR), were not significantly altered by BCE supplementation, protein expression of mature sterol-regulatory element-binding protein and LDLR was significantly increased with no change in HMGR protein. The expression of proprotein convertase subtilisin/kexin type 9 that facilitates LDLR protein degradation, as well as one of its transcriptional regulators, i.e. hepatocyte nuclear factor 4α, was significantly decreased in the livers of mice fed BCE. Taken together, BCE supplementation decreased plasma TC and glucose, and inhibited liver steatosis, suggesting that this berry may be consumed to prevent metabolic dysfunctions induced by diets high in fat and cholesterol. PMID:25899149

  14. Enteric neuropathy can be induced by high fat diet in vivo and palmitic acid exposure in vitro.

    Directory of Open Access Journals (Sweden)

    Ulrikke Voss

    Full Text Available OBJECTIVE: Obese and/or diabetic patients have elevated levels of free fatty acids and increased susceptibility to gastrointestinal symptoms. Since the enteric nervous system is pivotal in regulating gastrointestinal functions alterations or neuropathy in the enteric neurons are suspected to occur in these conditions. Lipid induced intestinal changes, in particular on enteric neurons, were investigated in vitro and in vivo using primary cell culture and a high fat diet (HFD mouse model. DESIGN: Mice were fed normal or HFD for 6 months. Intestines were analyzed for neuronal numbers, remodeling and lipid accumulation. Co-cultures of myenteric neurons, glia and muscle cells from rat small intestine, were treated with palmitic acid (PA (0 - 10(-3 M and / or oleic acid (OA (0 - 10(-3 M, with or without modulators of intracellular lipid metabolism. Analyses were by immunocyto- and histochemistry. RESULTS: HFD caused substantial loss of myenteric neurons, leaving submucous neurons unaffected, and intramuscular lipid accumulation in ileum and colon. PA exposure in vitro resulted in neuronal shrinkage, chromatin condensation and a significant and concentration-dependent decrease in neuronal survival; OA exposure was neuroprotective. Carnitine palmitoyltransferase 1 inhibition, L-carnitine- or alpha lipoic acid supplementation all counteracted PA-induced neuronal loss. PA or OA alone both caused a significant and concentration-dependent loss of muscle cells in vitro. Simultaneous exposure of PA and OA promoted survival of muscle cells and increased intramuscular lipid droplet accumulation. PA exposure transformed glia from a stellate to a rounded phenotype but had no effect on their survival. CONCLUSIONS: HFD and PA exposure are detrimental to myenteric neurons. Present results indicate excessive palmitoylcarnitine formation and exhausted L-carnitine stores leading to energy depletion, attenuated acetylcholine synthesis and oxidative stress to be main

  15. Anesthetic drug midazolam inhibits cardiac human ether-à-go-go-related gene channels: mode of action

    Directory of Open Access Journals (Sweden)

    Vonderlin N

    2015-02-01

    Full Text Available Nadine Vonderlin,1 Fathima Fischer,1 Edgar Zitron,1,2 Claudia Seyler,1 Daniel Scherer,1 Dierk Thomas,1,2 Hugo A Katus,1,2 Eberhard P Scholz1 1Department of Internal Medicine III, University Hospital Heidelberg, 2German Centre for Cardiovascular Research, Partner Site Heidelberg/Mannheim, Heidelberg, Germany Abstract: Midazolam is a short-acting benzodiazepine that is in wide clinical use as an anxiolytic, sedative, hypnotic, and anticonvulsant. Midazolam has been shown to inhibit ion channels, including calcium and potassium channels. So far, the effects of midazolam on cardiac human ether-à-go-go-related gene (hERG channels have not been analyzed. The inhibitory effects of midazolam on heterologously expressed hERG channels were analyzed in Xenopus oocytes using the double-electrode voltage clamp technique. We found that midazolam inhibits hERG channels in a concentration-dependent manner, yielding an IC50 of 170 µM in Xenopus oocytes. When analyzed in a HEK 293 cell line using the patch-clamp technique, the IC50 was 13.6 µM. Midazolam resulted in a small negative shift of the activation curve of hERG channels. However, steady-state inactivation was not significantly affected. We further show that inhibition is state-dependent, occurring within the open and inactivated but not in the closed state. There was no frequency dependence of block. Using the hERG pore mutants F656A and Y652A we provide evidence that midazolam uses a classical binding site within the channel pore. Analyzing the subacute effects of midazolam on hERG channel trafficking, we further found that midazolam does not affect channel surface expression. Taken together, we show that the anesthetic midazolam is a low-affinity inhibitor of cardiac hERG channels without additional effects on channel surface expression. These data add to the current understanding of the pharmacological profile of the anesthetic midazolam. Keywords: midazolam, anesthetics, human ether

  16. Evaluation of Beneficial Metabolic Effects of Berries in High-Fat Fed C57BL/6J Mice

    Directory of Open Access Journals (Sweden)

    Lovisa Heyman

    2014-01-01

    Full Text Available Objective. The aim of the study was to screen eight species of berries for their ability to prevent obesity and metabolic abnormalities associated with type 2 diabetes. Methods. C57BL/6J mice were assigned the following diets for 13 weeks: low-fat diet, high-fat diet or high-fat diet supplemented (20% with lingonberry, blackcurrant, bilberry, raspberry, açai, crowberry, prune or blackberry. Results. The groups receiving a high-fat diet supplemented with lingonberries, blackcurrants, raspberries or bilberries gained less weight and had lower fasting insulin levels than the control group receiving high-fat diet without berries. Lingonberries, and also blackcurrants and bilberries, significantly decreased body fat content, hepatic lipid accumulation, and plasma levels of the inflammatory marker PAI-1, as well as mediated positive effects on glucose homeostasis. The group receiving açai displayed increased weight gain and developed large, steatotic livers. Quercetin glycosides were detected in the lingonberry and the blackcurrant diets. Conclusion. Lingonberries were shown to fully or partially prevent the detrimental metabolic effects induced by high-fat diet. Blackcurrants and bilberries had similar properties, but to a lower degree. We propose that the beneficial metabolic effects of lingonberries could be useful in preventing obesity and related disorders.

  17. Maternal Methyl Donors Supplementation during Lactation Prevents the Hyperhomocysteinemia Induced by a High-Fat-Sucrose Intake by Dams

    Directory of Open Access Journals (Sweden)

    Paul Cordero

    2013-12-01

    Full Text Available Maternal perinatal nutrition may program offspring metabolic features. Epigenetic regulation is one of the candidate mechanisms that may be affected by maternal dietary methyl donors intake as potential controllers of plasma homocysteine levels. Thirty-two Wistar pregnant rats were randomly assigned into four dietary groups during lactation: control, control supplemented with methyl donors, high-fat-sucrose and high-fat-sucrose supplemented with methyl donors. Physiological outcomes in the offspring were measured, including hepatic mRNA expression and global DNA methylation after weaning. The newborns whose mothers were fed the obesogenic diet were heavier longer and with a higher adiposity and intrahepatic fat content. Interestingly, increased levels of plasma homocysteine induced by the maternal high-fat-sucrose dietary intake were prevented in both sexes by maternal methyl donors supplementation. Total hepatic DNA methylation decreased in females due to maternal methyl donors administration, while Dnmt3a hepatic mRNA levels decreased accompanying the high-fat-sucrose consumption. Furthermore, a negative association between Dnmt3a liver mRNA levels and plasma homocysteine concentrations was found. Maternal high-fat-sucrose diet during lactation could program offspring obesity features, while methyl donors supplementation prevented the onset of high hyperhomocysteinemia. Maternal dietary intake also affected hepatic DNA methylation metabolism, which could be linked with the regulation of the methionine-homocysteine cycle.

  18. Tetradecylthioacetic acid prevents high fat diet induced adiposity and insulin resistance

    DEFF Research Database (Denmark)

    Madsen, Lise; Guerre-Millo, Michéle; Flindt, Esben N;

    2002-01-01

    Tetradecylthioacetic acid (TTA) is a non-beta-oxidizable fatty acid analog, which potently regulates lipid homeostasis. Here we evaluate the ability of TTA to prevent diet-induced and genetically determined adiposity and insulin resistance. In Wistar rats fed a high fat diet, TTA administration...... completely prevented diet-induced insulin resistance and adiposity. In genetically obese Zucker (fa/fa) rats TTA treatment reduced the epididymal adipose tissue mass and improved insulin sensitivity. All three rodent peroxisome proliferator-activated receptor (PPAR) subtypes were activated by TTA in the...... ranking order PPARalpha > PPARdelta > PPARgamma. Expression of PPARgamma target genes in adipose tissue was unaffected by TTA treatment, whereas the hepatic expression of PPARalpha-responsive genes encoding enzymes involved in fatty acid uptake, transport, and oxidation was induced. This was accompanied...

  19. Chronic high-fat diet in fathers programs ß-cell dysfunction in female rat offspring

    DEFF Research Database (Denmark)

    Ng, Sheau-Fang; Lin, Ruby C Y; Laybutt, D Ross;

    2010-01-01

    The global prevalence of obesity is increasing across most ages in both sexes. This is contributing to the early emergence of type 2 diabetes and its related epidemic. Having either parent obese is an independent risk factor for childhood obesity. Although the detrimental impacts of diet-induced ......The global prevalence of obesity is increasing across most ages in both sexes. This is contributing to the early emergence of type 2 diabetes and its related epidemic. Having either parent obese is an independent risk factor for childhood obesity. Although the detrimental impacts of diet......-induced maternal obesity on adiposity and metabolism in offspring are well established, the extent of any contribution of obese fathers is unclear, particularly the role of non-genetic factors in the causal pathway. Here we show that paternal high-fat-diet (HFD) exposure programs ß-cell 'dysfunction' in rat F(1...

  20. Ameliorative Potential of Tamarindus indica on High Fat Diet Induced Nonalcoholic Fatty Liver Disease in Rats

    Directory of Open Access Journals (Sweden)

    Suja Rani Sasidharan

    2014-01-01

    Full Text Available Nonalcoholic fatty liver disease (NAFLD, the prevalence of which is rising globally with current upsurge in obesity, is one of the most frequent causes of chronic liver diseases. The present study evaluated the ameliorative effect of extract of Tamarindus indica seed coat (ETS on high fat diet (HFD induced NAFLD, after daily administration at 45, 90, and 180 mg/kg body weight dose levels for a period of 6 weeks, in albino Wistar rats. Treatment with ETS at all tested dose levels significantly attenuated the pathological alterations associated with HFD induced NAFLD viz. hepatomegaly, elevated hepatic lipid and lipid peroxides, serum alanine aminotransferase, and free fatty acid levels as well as micro-/macrohepatic steatosis. Moreover, extract treatment markedly reduced body weight and adiposity along with an improvement in insulin resistance index. The study findings, therefore suggested the therapeutic potential of ETS against NAFLD, acting in part through antiobesity, insulin sensitizing, and antioxidant mechanisms.

  1. High-fat feeding increases hepatic vitamin C synthesis and its circulatory mobilization in mice

    DEFF Research Database (Denmark)

    Christensen, Britt Tranberg; Hansen, Axel Jacob Kornerup; Lykkesfeldt, Jens

    2014-01-01

    PURPOSE: Vitamin C (vitC) deficiency has been linked to obesity and increased risk of cardiovascular disease and type 2 diabetes. Whereas humans are unable to synthesize vitC and therefore to compensate for increased turnover, we investigated whether mice-independent of dietary vitC-are able to...... modulate their vitC homeostasis during high-fat (HF) feeding. METHODS: Twenty-five male 5-week-old C57BL/6 mice were fed high- or low-fat diets for 14 weeks. An oral glucose tolerance test (OGTT) was performed after 12 weeks of intervention. Terminal fasting plasma samples were analyzed for insulin......, glucose and vitC concentrations. Hepatic vitC concentration and gulonolactone oxidase (GLO) capacity, as a measure of vitC de novo biosynthesis, were analyzed in liver homogenates. RESULTS: HF diet significantly increased plasma concentrations of vitC compared with a control diet low in fat (P < 0...

  2. Hypolipidemic activity ofPiper betel in high fat diet induced hyperlipidemic rat

    Institute of Scientific and Technical Information of China (English)

    Thirunavukkarasu Thirumalai; Narayanaswamy Tamilselvan; Ernest David

    2014-01-01

    Objective:To evaluate the hypolipidemic effect ofPiper betel(P. betel) in high fat diet induced hyperlipidemia rat.Methods:The methanol leaf extract was tested for hypolipidemic effect in the albino rats at the selected optimum dosage of250 mg/kg body weight and administered orally.Adult male albino rats of six numbers in each group were undertaken study and evaluated. Results:In groupII animals, the activity levels of serum total cholesterol(TC), triglycerides (TG), low density lipoprotein(LDL) and very low density lipoprotein-cholesterol(VLDL) were significantly enhanced when compared to that of normal rat.Conclusion:It could be said that the methanolic leaf extract ofP. betel exhibited a significant hypolipidemic effect.

  3. One-year high fat diet affects muscle-but not brain mitochondria

    DEFF Research Database (Denmark)

    Joergensen, Tenna; Grunnet, Niels; Quistorff, Bjørn

    2015-01-01

    It is well known that few weeks of high fat (HF) diet may induce metabolic disturbances and mitochondrial dysfunction in skeletalmuscle. However, little is known about the effects of long-term HF exposure and effects on brain mitochondria are unknown. Wistarrats were fed either chow (13E% fat) or...... HF diet (60E% fat) for 1 year. The HF animals developed obesity, dyslipidemia, insulinresistance, and dysfunction of isolated skeletal muscle mitochondria: state 3 and state 4 were 30% to 50% increased (P < 0.058)with palmitoyl carnitine (PC), while there was no effect with pyruvate as substrate....... Adding also succinate in state 3 resulted in ahigher substrate control ratio (SCR) with PC, but a lower SCR with pyruvate (P < 0.05). The P/O2 ratio was lower with PC (P < 0.004).However, similar tests on isolated brain mitochondria from the same animal showed no changes with the substrates relevant...

  4. Nociceptin receptor antagonist SB 612111 decreases high fat diet binge eating.

    Science.gov (United States)

    Hardaway, J Andrew; Jensen, Jennifer; Kim, Michelle; Mazzone, Christopher M; Sugam, Jonathan A; Diberto, Jeffrey F; Lowery-Gionta, Emily G; Hwa, Lara S; Pleil, Kristen E; Bulik, Cynthia M; Kash, Thomas L

    2016-07-01

    Binge eating is a dysregulated form of feeding behavior that occurs in multiple eating disorders including binge-eating disorder, the most common eating disorder. Feeding is a complex behavioral program supported through the function of multiple brain regions and influenced by a diverse array of receptor signaling pathways. Previous studies have shown the overexpression of the opioid neuropeptide nociceptin (orphanin FQ, N/OFQ) can induce hyperphagia, but the role of endogenous nociceptin receptor (NOP) in naturally occurring palatability-induced hyperphagia is unknown. In this study we adapted a simple, replicable form of binge eating of high fat food (HFD). We found that male and female C57BL/6J mice provided with daily one-hour access sessions to HFD eat significantly more during this period than those provided with continuous 24h access. This form of feeding is rapid and entrained. Chronic intermittent HFD binge eating produced hyperactivity and increased light zone exploration in the open field and light-dark assays respectively. Treatment with the potent and selective NOP antagonist SB 612111 resulted in a significant dose-dependent reduction in binge intake in both male and female mice, and, unlike treatment with the serotonin selective reuptake inhibitor fluoxetine, produced no change in total 24-h food intake. SB 612111 treatment also significantly decreased non-binge-like acute HFD consumption in male mice. These data are consistent with the hypothesis that high fat binge eating is modulated by NOP signaling and that the NOP system may represent a promising novel receptor to explore for the treatment of binge eating. PMID:27036650

  5. Early limited nitrosamine exposures exacerbate high fat diet-mediated type 2 diabetes and neurodegeneration

    Directory of Open Access Journals (Sweden)

    Longato Lisa

    2010-03-01

    Full Text Available Abstract Background Type 2 diabetes mellitus (T2DM and several types of neurodegeneration, including Alzheimer's, are linked to insulin-resistance, and chronic high dietary fat intake causes T2DM with mild neurodegeneration. Intra-cerebral Streptozotocin, a nitrosamine-related compound, causes neurodegeneration, whereas peripheral treatment causes DM. Hypothesis Limited early exposures to nitrosamines that are widely present in the environment, enhance the deleterious effects of high fat intake in promoting T2DM and neurodegeneration. Methods Long Evans rat pups were treated with N-nitrosodiethylamine (NDEA by i.p. injection, and upon weaning, they were fed with high fat (60%; HFD or low fat (5%; LFD chow for 8 weeks. Cerebella were harvested to assess gene expression, and insulin and insulin-like growth factor (IGF deficiency and resistance in the context of neurodegeneration. Results HFD ± NDEA caused T2DM, neurodegeneration with impairments in brain insulin, insulin receptor, IGF-2 receptor, or insulin receptor substrate gene expression, and reduced expression of tau and choline acetyltransferase (ChAT, which are regulated by insulin and IGF-1. In addition, increased levels of 4-hydroxynonenal and nitrotyrosine were measured in cerebella of HFD ± NDEA treated rats, and overall, NDEA+HFD treatment reduced brain levels of Tau, phospho-GSK-3β (reflecting increased GSK-3β activity, glial fibrillary acidic protein, and ChAT to greater degrees than either treatment alone. Finally, pro-ceramide genes, examined because ceramides cause insulin resistance, oxidative stress, and neurodegeneration, were significantly up-regulated by HFD and/or NDEA exposure, but the highest levels were generally present in brains of HFD+NDEA treated rats. Conclusions Early limited exposure to nitrosamines exacerbates the adverse effects of later chronic high dietary fat intake in promoting T2DM and neurodegeneration. The mechanism involves increased generation of

  6. High-fat diet-induced brain region-specific phenotypic spectrum of CNS resident microglia.

    Science.gov (United States)

    Baufeld, Caroline; Osterloh, Anja; Prokop, Stefan; Miller, Kelly R; Heppner, Frank L

    2016-09-01

    Diets high in fat (HFD) are known to cause an immune response in the periphery as well as the central nervous system. In peripheral adipose tissue, this immune response is primarily mediated by macrophages that are recruited to the tissue. Similarly, reactivity of microglia, the innate immune cells of the brain, has been shown to occur in the hypothalamus of mice fed a high-fat diet. To characterize the nature of the microglial response to diets high in fat in a temporal fashion, we studied the phenotypic spectrum of hypothalamic microglia of mice fed high-fat diet for 3 days and 8 weeks by assessing their tissue reaction and inflammatory signature. While we observed a significant increase in Iba1+ myeloid cells and a reaction of GFAP+ astrocytes in the hypothalamus after 8 weeks of HFD feeding, we found the hypothalamic myeloid cell reaction to be limited to endogenous microglia and not mediated by infiltrating myeloid cells. Moreover, obese humans were found to present with signs of hypothalamic gliosis and exacerbated microglia dystrophy, suggesting a targeted microglia response to diet in humans as well. Notably, the glial reaction occurring in the mouse hypothalamus was not accompanied by an increase in pro-inflammatory cytokines, but rather by an anti-inflammatory reaction. Gene expression analyses of isolated microglia not only confirmed this observation, but also revealed a downregulation of microglia genes important for sensing signals in the microenvironment. Finally, we demonstrate that long-term exposure of microglia to HFD in vivo does not impair the cell's ability to respond to additional stimuli, like lipopolysaccharide. Taken together, our findings support the notion that microglia react to diets high in fat in a region-specific manner in rodents as well as in humans; however, this response changes over time as it is not exclusively pro-inflammatory nor does exposure to HFD prime microglia in the hypothalamus. PMID:27393312

  7. Lamp-2 deficiency prevents high-fat diet-induced obese diabetes via enhancing energy expenditure

    Energy Technology Data Exchange (ETDEWEB)

    Yasuda-Yamahara, Mako [Department of Medicine, Shiga University of Medical Science, Otsu, Shiga (Japan); Kume, Shinji, E-mail: skume@belle.shiga-med.ac.jp [Department of Medicine, Shiga University of Medical Science, Otsu, Shiga (Japan); Yamahara, Kosuke; Nakazawa, Jun; Chin-Kanasaki, Masami; Araki, Hisazumi; Araki, Shin-ichi [Department of Medicine, Shiga University of Medical Science, Otsu, Shiga (Japan); Koya, Daisuke [Department of Diabetology and Endocrinology, Kanazawa Medical University, Kahoku-Gun, Ishikawa (Japan); Haneda, Masakzu [Division of Metabolism and Biosystemic Science, Asahikawa Medical University, Asahikawa, Hokkaido (Japan); Ugi, Satoshi; Maegawa, Hiroshi; Uzu, Takashi [Department of Medicine, Shiga University of Medical Science, Otsu, Shiga (Japan)

    2015-09-18

    Autophagy process is essential for maintaining intracellular homeostasis and consists of autophagosome formation and subsequent fusion with lysosome for degradation. Although the role of autophagosome formation in the pathogenesis of diabetes has been recently documented, the role of the latter process remains unclear. This study analyzed high-fat diet (HFD)-fed mice lacking lysosome-associated membrane protein-2 (lamp-2), which is essential for the fusion with lysosome and subsequent degradation of autophagosomes. Although lamp-2 deficient mice showed little alteration in glucose metabolism under normal diet feeding, they showed a resistance against high-fat diet (HFD)-induced obesity, hyperinsulinemic hyperglycemia and tissues lipid accumulation, accompanied with higher energy expenditure. The expression levels of thermogenic genes in brown adipose tissue were significantly increased in HFD-fed lamp-2-deficient mice. Of some serum factors related to energy expenditure, the serum level of fibroblast growth factor (FGF) 21 and its mRNA expression level in the liver were significantly higher in HFD-fed lamp-2-deficient mice in an ER stress-, but not PPARα-, dependent manner. In conclusion, a lamp-2-depenedent fusion and degradation process of autophagosomes is involved in the pathogenesis of obese diabetes, providing a novel insight into autophagy and diabetes. - Highlights: • Lamp-2 is essential for autophagosome fusion with lysosome and its degradation. • Lamp-2 deficiency lead to a resistance to diet-induced obese diabetes in mice. • Lamp-2 deficiency increased whole body energy expenditure under HFD-feeding. • Lamp-2 deficiency elevated the serum level of FGF21 under HFD-feeding.

  8. Lamp-2 deficiency prevents high-fat diet-induced obese diabetes via enhancing energy expenditure

    International Nuclear Information System (INIS)

    Autophagy process is essential for maintaining intracellular homeostasis and consists of autophagosome formation and subsequent fusion with lysosome for degradation. Although the role of autophagosome formation in the pathogenesis of diabetes has been recently documented, the role of the latter process remains unclear. This study analyzed high-fat diet (HFD)-fed mice lacking lysosome-associated membrane protein-2 (lamp-2), which is essential for the fusion with lysosome and subsequent degradation of autophagosomes. Although lamp-2 deficient mice showed little alteration in glucose metabolism under normal diet feeding, they showed a resistance against high-fat diet (HFD)-induced obesity, hyperinsulinemic hyperglycemia and tissues lipid accumulation, accompanied with higher energy expenditure. The expression levels of thermogenic genes in brown adipose tissue were significantly increased in HFD-fed lamp-2-deficient mice. Of some serum factors related to energy expenditure, the serum level of fibroblast growth factor (FGF) 21 and its mRNA expression level in the liver were significantly higher in HFD-fed lamp-2-deficient mice in an ER stress-, but not PPARα-, dependent manner. In conclusion, a lamp-2-depenedent fusion and degradation process of autophagosomes is involved in the pathogenesis of obese diabetes, providing a novel insight into autophagy and diabetes. - Highlights: • Lamp-2 is essential for autophagosome fusion with lysosome and its degradation. • Lamp-2 deficiency lead to a resistance to diet-induced obese diabetes in mice. • Lamp-2 deficiency increased whole body energy expenditure under HFD-feeding. • Lamp-2 deficiency elevated the serum level of FGF21 under HFD-feeding

  9. Rhinacanthus nasutus leaf improves metabolic abnormalities in high-fat diet-induced obese mice

    Institute of Scientific and Technical Information of China (English)

    Supaporn Wannasiri; Pritsana Piyabhan; Jarinyaporn Naowaboot

    2016-01-01

    Objective: To investigate the effect of Rhinacanthus nasutus (R. nasutus) leaf extract on impaired glucose and lipid metabolism in obese ICR mice. Methods: Obesity was induced in the male ICR mice by feeding them a high-fat diet (60 kcal% fat) for 12 weeks. After the first six weeks of the diet, the obese mice were administered with the water extract of R. nasutus leaves at 250 and 500 mg/kg per day for the next six weeks. Subsequently, the blood glucose, lipid profiles, insulin, leptin, and adiponectin levels were measured. The liver and adipose tissues were excised for his-topathological examination and protein expression study. Results: After six weeks of the treatment, R. nasutus extract (at 250 and 500 mg/kg per day) was found to reduce the elevated blood glucose level, improve the insulin sensitivity, decrease the serum leptin, and increase the serum adiponectin levels. The obese mice treated with R. nasutus were found to have a reduction in the increased lipid concen-trations in their serum and liver tissues. Moreover, treatment with R. nasutus reduced the fat accumulation in the liver and the large adipocyte size in the fat tissues. Interestingly, the administration with R. nasutus extract was marked by an increase in the hepatic peroxisome proliferators-activated receptor alpha, fat cell adiponectin, and glucose transporter 4 proteins. Conclusions: To the best of our knowledge, the present study is the first report on the impact of R. nasutus extract in improving the impaired glucose and lipid metabolism in high-fat diet-induced obesity in mice via stimulating the insulin sensitivity in the liver and adipose tissues.

  10. Chronic subhepatotoxic exposure to arsenic enhances hepatic injury caused by high fat diet in mice

    International Nuclear Information System (INIS)

    Arsenic is a ubiquitous contaminant in drinking water. Whereas arsenic can be directly hepatotoxic, the concentrations/doses required are generally higher than present in the US water supply. However, physiological/biochemical changes that are alone pathologically inert can enhance the hepatotoxic response to a subsequent stimulus. Such a ‘2-hit’ paradigm is best exemplified in chronic fatty liver diseases. Here, the hypothesis that low arsenic exposure sensitizes liver to hepatotoxicity in a mouse model of non-alcoholic fatty liver disease was tested. Accordingly, male C57Bl/6J mice were exposed to low fat diet (LFD; 13% calories as fat) or high fat diet (HFD; 42% calories as fat) and tap water or arsenic (4.9 ppm as sodium arsenite) for ten weeks. Biochemical and histologic indices of liver damage were determined. High fat diet (± arsenic) significantly increased body weight gain in mice compared with low-fat controls. HFD significantly increased liver to body weight ratios; this variable was unaffected by arsenic exposure. HFD caused steatohepatitis, as indicated by histological assessment and by increases in plasma ALT and AST. Although arsenic exposure had no effect on indices of liver damage in LFD-fed animals, it significantly increased the liver damage caused by HFD. This effect of arsenic correlated with enhanced inflammation and fibrin extracellular matrix (ECM) deposition. These data indicate that subhepatotoxic arsenic exposure enhances the toxicity of HFD. These results also suggest that arsenic exposure might be a risk factor for the development of fatty liver disease in human populations. -- Highlights: ► Characterizes a mouse model of arsenic enhanced NAFLD. ► Arsenic synergistically enhances experimental fatty liver disease at concentrations that cause no overt hepatotoxicity alone. ► This effect is associated with increased inflammation.

  11. Synergistic effects of high fat feeding and apolipoprotein E deletion on enterocytic amyloid-beta abundance

    Directory of Open Access Journals (Sweden)

    Dhaliwal Satvinder S

    2008-04-01

    Full Text Available Abstract Background Amyloid-β (Aβ, a key protein found in amyloid plaques of subjects with Alzheimer's disease is expressed in the absorptive epithelial cells of the small intestine. Ingestion of saturated fat significantly enhances enterocytic Aβ abundance whereas fasting abolishes expression. Apolipoprotein (apo E has been shown to directly modulate Aβ biogenesis in liver and neuronal cells but it's effect in enterocytes is not known. In addition, apo E modulates villi length, which may indirectly modulate Aβ as a consequence of differences in lipid absorption. This study compared Aβ abundance and villi length in wild-type (WT and apo E knockout (KO mice maintained on either a low-fat or high-fat diet. Wild-type C57BL/6J and apo E KO mice were randomised for six-months to a diet containing either 4% (w/w unsaturated fats, or chow comprising 16% saturated fats and 1% cholesterol. Quantitative immunohistochemistry was used to assess Aβ abundance in small intestinal enterocytes. Apo E KO mice given the low-fat diet had similar enterocytic Aβ abundance compared to WT controls. Results The saturated fat diet substantially increased enterocytic Aβ in WT and in apo E KO mice, however the effect was greater in the latter. Villi height was significantly greater in apo E KO mice than for WT controls when given the low-fat diet. However, WT mice had comparable villi length to apo E KO when fed the saturated fat and cholesterol enriched diet. There was no effect of the high-fat diet on villi length in apo E KO mice. Conclusion The findings of this study are consistent with the notion that lipid substrate availability modulates enterocytic Aβ. Apo E may influence enterocytic lipid availability by modulating absorptive capacity.

  12. High fat diet accelerates pathogenesis of murine Crohn's disease-like ileitis independently of obesity.

    Directory of Open Access Journals (Sweden)

    Lisa Gruber

    Full Text Available BACKGROUND: Obesity has been associated with a more severe disease course in inflammatory bowel disease (IBD and epidemiological data identified dietary fats but not obesity as risk factors for the development of IBD. Crohn's disease is one of the two major IBD phenotypes and mostly affects the terminal ileum. Despite recent observations that high fat diets (HFD impair intestinal barrier functions and drive pathobiont selection relevant for chronic inflammation in the colon, mechanisms of high fat diets in the pathogenesis of Crohn's disease are not known. The aim of this study was to characterize the effect of HFD on the development of chronic ileal inflammation in a murine model of Crohn's disease-like ileitis. METHODS: TNF(ΔARE/WT mice and wildtype C57BL/6 littermates were fed a HFD compared to control diet for different durations. Intestinal pathology and metabolic parameters (glucose tolerance, mesenteric tissue characteristics were assessed. Intestinal barrier integrity was characterized at different levels including polyethylene glycol (PEG translocation, endotoxin in portal vein plasma and cellular markers of barrier function. Inflammatory activation of epithelial cells as well as immune cell infiltration into ileal tissue were determined and related to luminal factors. RESULTS: HFD aggravated ileal inflammation but did not induce significant overweight or typical metabolic disorders in TNF(ΔARE/WT. Expression of the tight junction protein Occludin was markedly reduced in the ileal epithelium of HFD mice independently of inflammation, and translocation of endotoxin was increased. Epithelial cells showed enhanced expression of inflammation-related activation markers, along with enhanced luminal factors-driven recruitment of dendritic cells and Th17-biased lymphocyte infiltration into the lamina propria. CONCLUSIONS: HFD feeding, independently of obesity, accelerated disease onset of small intestinal inflammation in Crohn's disease

  13. Nociceptin receptor antagonist SB 612111 decreases high fat diet binge eating

    Science.gov (United States)

    Hardaway, J. Andrew; Jensen, Jennifer; Kim, Michelle; Mazzone, Christopher M.; Sugam, Jonathan A.; Diberto, Jeffrey F.; Lowery-Gionta, Emily G.; Hwa, Lara S.; Pleil, Kristen E.; Bulik, Cynthia M.; Kash, Thomas L.

    2016-01-01

    Binge eating is a dysregulated form of feeding behavior that occurs in multiple eating disorders including binge-eating disorder, the most common eating disorder. Feeding is a complex behavioral program supported through the function of multiple brain regions and influenced by a diverse array of receptor signaling pathways. Previous studies have shown the overexpression of the opioid neuropeptide nociceptin (orphanin FQ, N/OFQ) can induce hyperphagia, but the role of endogenous nociceptin receptor (NOP) in naturally occurring palatability-induced hyperphagia is unknown. In this study we adapted a simple, replicable form of binge eating of high fat food (HFD). We found that male and female C57BL/6J mice provided with daily one-hour access sessions to HFD eat significantly more during this period than those provided with continuous 24 hour access. This form of feeding is rapid and entrained. Chronic intermittent HFD binge eating produced hyperactivity and increased light zone exploration in the open field and light-dark assays respectively. Treatment with the potent and selective NOP antagonist SB 612111 resulted in a significant dose-dependent reduction in binge intake in both male and female mice, and, unlike treatment with the serotonin selective reuptake inhibitor fluoxetine, produced no change in total 24-hour food intake. SB 612111 treatment also significantly decreased non-binge-like acute HFD consumption in male mice. These data are consistent with the hypothesis that high fat binge eating is modulated by NOP signaling and that the NOP system may represent a promising novel receptor to explore for the treatment of binge eating. PMID:27036650

  14. Edible bird’s nest attenuates procoagulation effects of high-fat diet in rats

    Directory of Open Access Journals (Sweden)

    Yida Z

    2015-07-01

    Full Text Available Zhang Yida,1,2 Mustapha Umar Imam,1 Maznah Ismail,1,3 Norsharina Ismail,1 Zhiping Hou1 1Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 2Cardiology Department, Affiliated Hospital of Chengde Medical University, Chengde, Hebei, People’s Republic of China; 3Faculty of Medicine and Health Sciences, Department of Nutrition and Dietetics, Universiti Putra Malaysia, Serdang, Selangor, Malaysia Abstract: Edible bird’s nest (EBN is popular in Asia, and has long been used traditionally as a supplement. There are, however, limited evidence-based studies on its efficacy. EBN has been reported to improve dyslipidemia, which is closely linked to hypercoagulation states. In the present study, the effects of EBN on high-fat diet- (HFD- induced coagulation in rats were evaluated. Rats were fed for 12 weeks with HFD alone or in combination with simvastatin or EBN. Food intake was estimated, and weight measurements were made during the experimental period. After sacrifice, serum oxidized low-density lipo­protein (oxLDL, adiponectin, leptin, von willibrand factor, prostacyclin, thromboxane and lipid profile, and whole blood coagulation indices (bleeding time, prothrombin time, activated partial thromboplastin time, red blood count count, and platelet count were estimated. Furthermore, hepatic expression of coagulation-related genes was evaluated using multiplex polymerase chain reaction. The results indicated that EBN could attenuate HFD-induced hypercholesterolemia and coagulation similar to simvastatin, partly through transcriptional regulation of coagulation-related genes. The results suggested that EBN has the potential for lowering the risk of cardiovascular disease-related hypercoagulation due to hypercholesterolemia. Keywords: edible bird’s nest, coagulation, high-fat diet, hypercholesterolemia, nutrigeno­mics

  15. Monascus-fermented yellow pigments monascin and ankaflavin showed antiobesity effect via the suppression of differentiation and lipogenesis in obese rats fed a high-fat diet.

    Science.gov (United States)

    Lee, Chun-Lin; Wen, Ja-Yan; Hsu, Ya-Wen; Pan, Tzu-Ming

    2013-02-20

    Monascus-fermented monascin and ankaflavin are found to strongly inhibit differentiation and lipogenesis and stimulate lipolysis effects in a 3T3-L1 preadipocyte model, but the in vivo regulation mechanism is unclear. This study uses obese rats caused by a high-fat diet to examine the effects of daily monascin and ankaflavin feeding (8 weeks) on antiobesity effects and modulation of differentiation, lipogenesis, and lipid absorption. The results show that monascin and ankaflavin had a significant antiobesity effect, which should result from the modulation of monascin and ankaflavin on the inhibition of differentiation by inhibiting CCAT/enhancer-binding protein β (C/EBPβ) expression (36.4% and 48.3%) and its downstream peroxisome proliferator-activated receptor γ (PPARγ) (55.6% and 64.5%) and CCAT/enhancer-binding protein α (C/EBPα) expressions (25.2% and 33.2%) and the inhibition of lipogenesis by increasing lipase activity (14.0% and 10.7%) and decreasing heparin releasable lipoprotein lipase (HR-LPL) activity (34.8% and 30.5%). Furthermore, monascin and ankaflavin are the first agents found to suppress Niemann-Pick C1 Like 1 (NPC1L1) protein expression (73.6% and 26.1%) associated with small intestine tissue lipid absorption. Importantly, monascin and ankaflavin are not like monacolin K, which increases creatine phosphokinase (CPK) activity, known as a rhabdomyolysis indicator. PMID:23360447

  16. Impact of short-term high-fat feeding on glucose and insulin metabolism in young healthy men

    DEFF Research Database (Denmark)

    Brøns, Charlotte; Jensen, Christine B.; Storgaard, Heidi;

    2009-01-01

    a control diet on hepatic and peripheral insulin action by a hyperinsulinaemic euglycaemic clamp, muscle mitochondrial function by (31)P magnetic resonance spectroscopy, and gene expression by qrt-PCR and microarray in 26 young men. Hepatic glucose production and fasting glucose levels increased...... significantly in response to overfeeding. However, peripheral insulin action, muscle mitochondrial function, and general and specific oxidative phosphorylation gene expression were unaffected by high-fat feeding. Insulin secretion increased appropriately to compensate for hepatic, and not for peripheral......, insulin resistance. High-fat feeding increased fasting levels of plasma adiponectin, leptin and gastric inhibitory peptide (GIP). High-fat overfeeding increases fasting glucose levels due to increased hepatic glucose production. The increased insulin secretion may compensate for hepatic insulin resistance...

  17. Effects of escin mixture from the seeds of Aesculus hippocastanum on obesity in mice fed a high fat diet.

    Science.gov (United States)

    Avci, Gülcan; Küçükkurt, Ismail; Küpeli Akkol, Esra; Yeşilada, Erdem

    2010-03-01

    Escins, a triterpene glycoside mixture obtained from the ethanol extract of Aesculus hippocastanum L. (Hippocastanaceae) seed, was evaluated for its in vivo effects on the plasma levels of some hormones (leptin, insulin, FT(3), FT(4)) and biochemical parameters (glucose, triglyceride, total cholesterol, HDL-C, LDL-C concentrations) in mice fed with a high fat diet for 5 weeks. A high fat diet induced a remarkable increment in the plasma leptin (p <0.01), total cholesterol (p <0.01) and LDL-C (p <0.001) concentrations compared to control group animals. Combined administration of a high-fat diet with escins decreased leptin (31.6%) (p<0.05) and FT(4) (36.0%) (p<0.05) levels, increased HDL-C concentration (17.0%), while remained ineffective on LDL-C concentration in mice. Results have shown that escins may have beneficial effects in the understanding of obesity. PMID:20645808

  18. Changes in Expression of Genes Regulating Airway Inflammation Following a High-Fat Mixed Meal in Asthmatics.

    Science.gov (United States)

    Li, Qian; Baines, Katherine J; Gibson, Peter G; Wood, Lisa G

    2016-01-01

    Consumption of a high fat meal can increase neutrophilic airway inflammation in asthma subjects. This study investigates the molecular mechanisms driving airway neutrophilia following a high fat meal in asthmatics. Subjects with asthma (n = 11) and healthy controls (n = 8) consumed a high-fat/energy meal, containing total energy (TE) of 3846 kJ and 48 g of total fat (20.5 g saturated). Sputum was induced at 0 and 4 h, and gene expression was examined by microarray and quantitative real-time PCR (qPCR). Following the high fat dietary challenge, 168 entities were significantly differentially expressed greater than >1.5 fold in subjects with asthma, whereas, in healthy controls, only 14 entities were differentially expressed. Of the 168 genes that were changed in asthma, several biological processes were overrepresented, with 25 genes involved in "immune system processes". qPCR confirmed that S100P, S100A16, MAL and MUC1 were significantly increased in the asthma group post-meal. We also observed a strong correlation and a moderate correlation between the change in NLRP12 and S100A16 gene expression at 4 h compared to baseline, and the change in total and saturated non-esterified plasma fatty acid levels at 2 h compared to baseline. In summary, our data identifies differences in inflammatory gene expression that may contribute to increased airway neutrophilia following a high fat meal in subjects with asthma and may provide useful therapeutic targets for immunomodulation. This may be particularly relevant to obese asthmatics, who are habitually consuming diets with a high fat content. PMID:26751474

  19. Changes in Expression of Genes Regulating Airway Inflammation Following a High-Fat Mixed Meal in Asthmatics

    Directory of Open Access Journals (Sweden)

    Qian Li

    2016-01-01

    Full Text Available Consumption of a high fat meal can increase neutrophilic airway inflammation in asthma subjects. This study investigates the molecular mechanisms driving airway neutrophilia following a high fat meal in asthmatics. Subjects with asthma (n = 11 and healthy controls (n = 8 consumed a high-fat/energy meal, containing total energy (TE of 3846 kJ and 48 g of total fat (20.5 g saturated. Sputum was induced at 0 and 4 h, and gene expression was examined by microarray and quantitative real-time PCR (qPCR. Following the high fat dietary challenge, 168 entities were significantly differentially expressed greater than >1.5 fold in subjects with asthma, whereas, in healthy controls, only 14 entities were differentially expressed. Of the 168 genes that were changed in asthma, several biological processes were overrepresented, with 25 genes involved in “immune system processes”. qPCR confirmed that S100P, S100A16, MAL and MUC1 were significantly increased in the asthma group post-meal. We also observed a strong correlation and a moderate correlation between the change in NLRP12 and S100A16 gene expression at 4 h compared to baseline, and the change in total and saturated non-esterified plasma fatty acid levels at 2 h compared to baseline. In summary, our data identifies differences in inflammatory gene expression that may contribute to increased airway neutrophilia following a high fat meal in subjects with asthma and may provide useful therapeutic targets for immunomodulation. This may be particularly relevant to obese asthmatics, who are habitually consuming diets with a high fat content.

  20. Compensatory hyperinsulinemia in high-fat diet-induced obese mice is associated with enhanced insulin translation in islets

    International Nuclear Information System (INIS)

    A high-fat diet (HF) is associated with obesity, insulin resistance, and hyperglycemia. Animal studies have shown compensatory mechanisms in pancreatic β-cells after high fat load, such as increased pancreatic β-cell mass, enhanced insulin secretion, and exocytosis. However, the effects of high fat intake on insulin synthesis are obscure. Here, we investigated whether insulin synthesis was altered in correlation with an HF diet, for the purpose of obtaining further understanding of the compensatory mechanisms in pancreatic β-cells. Mice fed an HF diet are obese, insulin resistant, hyperinsulinemic, and glucose intolerant. In islets of mice fed an HF diet, more storage of insulin was identified. We analyzed insulin translation in mouse islets, as well as in INS-1 cells, using non-radioisotope chemicals. We found that insulin translational levels were significantly increased in islets of mice fed an HF diet to meet systemic demand, without altering its transcriptional levels. Our data showed that not only increased pancreatic β-cell mass and insulin secretion but also elevated insulin translation is the major compensatory mechanism of pancreatic β-cells. - Highlights: • More stored insulin was recognized in islets of mice fed a high-fat diet. • Insulin translation was not enhanced by fatty acids, but by insulin demand. • Insulin transcription was not altered in islets of mice fed a high-fat diet. • Insulin translation was markedly enhanced in islets of mice fed a high-fat diet. • Non-radioisotope chemicals were used to measure insulin translation in mouse islets

  1. Bromocriptine increased operant responding for high fat food but decreased chow intake in both obesity-prone and resistant rats

    Energy Technology Data Exchange (ETDEWEB)

    Thanos, P.K.; Wang, G.; Thanos, P.K.; Cho, J. Kim, R.; Michaelides, M.; Primeaux, S.; Bray, G.; Wang, G.-J.; Volkow, N.D.

    2010-10-27

    Dopamine (DA) and DAD{sub 2} receptors (D2R) have been implicated in obesity and are thought to be involved in the rewarding properties of food. Osborne-Mendel (OM) rats are susceptible to diet induced obesity (DIO) while S5B/P (S5B) rats are resistant when given a high-fat diet. Here we hypothesized that the two strains would differ in high-fat food self-administration (FSA) and that the D2R agonist bromocriptine (BC) would differently affect their behavior. Ad-libitum fed OM and S5B/P rats were tested in a FSA operant chamber and were trained to lever press for high-fat food pellets under a fixed-ratio (FR1) and a progressive ratio (PR) schedule. After sixteen days of PR sessions, rats were treated with three different doses of BC (1, 10 and 20 mg/kg). No significant differences were found between the two strains in the number of active lever presses. BC treatment (10 mg/kg and 20 mg/kg) increased the number of active lever presses (10 mg/kg having the strongest effect) whereas it decreased rat chow intake in the home cage with equivalent effects in both strains. These effects were not observed on the day of BC administration but on the day following its administration. Our results suggest that these two strains have similar motivation for procuring high fat food using this paradigm. BC increased operant responding for high-fat pellets but decreased chow intake in both strains, suggesting that D2R stimulation may have enhanced the motivational drive to procure the fatty food while correspondingly decreasing the intake of regular food. These findings suggest that susceptibility to dietary obesity (prior to the onset of obesity) may not affect operant motivation for a palatable high fat food and that differential susceptibility to obesity may be related to differential sensitivity to D2R stimulation.

  2. Compensatory hyperinsulinemia in high-fat diet-induced obese mice is associated with enhanced insulin translation in islets

    Energy Technology Data Exchange (ETDEWEB)

    Kanno, Ayumi, E-mail: akanno@med.kobe-u.ac.jp [Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe 650-0017 (Japan); Asahara, Shun-ichiro, E-mail: asahara@med.kobe-u.ac.jp [Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe 650-0017 (Japan); Masuda, Katsuhisa, E-mail: katsuhisa.m.0707@gmail.com [Division of Medical Chemistry, Department of Biophysics, Kobe University Graduate School of Health Sciences, Kobe 654-0142 (Japan); Matsuda, Tomokazu, E-mail: tomokazu@med.kobe-u.ac.jp [Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe 650-0017 (Japan); Kimura-Koyanagi, Maki, E-mail: koyanagi@med.kobe-u.ac.jp [Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe 650-0017 (Japan); Seino, Susumu, E-mail: seino@med.kobe-u.ac.jp [Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe 650-0047 (Japan); Ogawa, Wataru, E-mail: ogawa@med.kobe-u.ac.jp [Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe 650-0017 (Japan); Kido, Yoshiaki, E-mail: kido@med.kobe-u.ac.jp [Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe 650-0017 (Japan); Division of Medical Chemistry, Department of Biophysics, Kobe University Graduate School of Health Sciences, Kobe 654-0142 (Japan)

    2015-03-13

    A high-fat diet (HF) is associated with obesity, insulin resistance, and hyperglycemia. Animal studies have shown compensatory mechanisms in pancreatic β-cells after high fat load, such as increased pancreatic β-cell mass, enhanced insulin secretion, and exocytosis. However, the effects of high fat intake on insulin synthesis are obscure. Here, we investigated whether insulin synthesis was altered in correlation with an HF diet, for the purpose of obtaining further understanding of the compensatory mechanisms in pancreatic β-cells. Mice fed an HF diet are obese, insulin resistant, hyperinsulinemic, and glucose intolerant. In islets of mice fed an HF diet, more storage of insulin was identified. We analyzed insulin translation in mouse islets, as well as in INS-1 cells, using non-radioisotope chemicals. We found that insulin translational levels were significantly increased in islets of mice fed an HF diet to meet systemic demand, without altering its transcriptional levels. Our data showed that not only increased pancreatic β-cell mass and insulin secretion but also elevated insulin translation is the major compensatory mechanism of pancreatic β-cells. - Highlights: • More stored insulin was recognized in islets of mice fed a high-fat diet. • Insulin translation was not enhanced by fatty acids, but by insulin demand. • Insulin transcription was not altered in islets of mice fed a high-fat diet. • Insulin translation was markedly enhanced in islets of mice fed a high-fat diet. • Non-radioisotope chemicals were used to measure insulin translation in mouse islets.

  3. Inhibition of phospholipase A2 (PLA2) activity by nifedipine and nisoldipine is independent of their calcium-channel-blocking activity

    International Nuclear Information System (INIS)

    The effects of several calcium antagonists on phospholipase A2 (PLA2) activity were examined. Nifedipine and nisoldipine inhibited a cell-free preparation of PLA2 in a dose-dependent manner with maximal inhibition of 71-77% observed at 100 microM. More potent or equipotent dihydropyridine calcium antagonists such as nitrendipine and felodipine did not inhibit PLA2 activity. In addition, nondihydropyridine calcium antagonists such as diltiazem, verapamil, and cinnarazine failed to reduce PLA2 activity markedly. Nifedipine and nisoldipine also reduced PLA2 activity in intact mouse peritoneal macrophages where PLA2 activity was monitored by free [14C]arachidonic acid release from [14C]arachidonic acid-prelabeled cells. When levels of PGE2 and LTC4 were measured by radioimmunoassay, it was found that the synthesis of these two metabolites was concomitantly inhibited by nifedipine and nisoldipine. In vivo, nifedipine and nisoldipine inhibited tetradecanoylphorbol acetate (TPA) induced ear edema. UV irradiation of nifedipine and nisoldipine (which destroys the slow calcium-channel-blocking activity of these compounds) did not result in a loss of PLA2 inhibitory activity. In fact, in both instances the UV-irradiated forms of nifedipine and nisoldipine were slightly more potent PLA2 inhibitors than the parent compound alone. We therefore conclude that the ability of nifedipine and nisoldipine to inhibit PLA2 was direct and unrelated to their actions on slow calcium channels

  4. Calcitriol inhibits Ether-a go-go potassium channel expression and cell proliferation in human breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Becerra, Rocio [Department of Reproductive Biology, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Vasco de Quiroga No. 15, Tlalpan 14000 Mexico, D.F. (Mexico); Diaz, Lorenza, E-mail: lorenzadiaz@gmail.com [Department of Reproductive Biology, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Vasco de Quiroga No. 15, Tlalpan 14000 Mexico, D.F. (Mexico); Camacho, Javier [Department of Pharmacology, Centro de Investigacion y de Estudios Avanzados, Instituto Politecnico Nacional, Av. Instituto Politecnico Nacional 2508, San Pedro Zacatenco 07360, Mexico, D.F. (Mexico); Barrera, David; Ordaz-Rosado, David; Morales, Angelica [Department of Reproductive Biology, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Vasco de Quiroga No. 15, Tlalpan 14000 Mexico, D.F. (Mexico); Ortiz, Cindy Sharon [Department of Pathology, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Vasco de Quiroga No. 15, Tlalpan 14000 Mexico, D.F. (Mexico); Avila, Euclides [Department of Reproductive Biology, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Vasco de Quiroga No. 15, Tlalpan 14000 Mexico, D.F. (Mexico); Bargallo, Enrique [Department of Breast Tumors, Instituto Nacional de Cancerologia, Av. San Fernando No. 22, Tlalpan 14080, Mexico, D.F. (Mexico); Arrecillas, Myrna [Department of Pathology, Instituto Nacional de Cancerologia, Av. San Fernando No. 22, Tlalpan 14080, Mexico, D.F. (Mexico); Halhali, Ali; Larrea, Fernando [Department of Reproductive Biology, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Vasco de Quiroga No. 15, Tlalpan 14000 Mexico, D.F. (Mexico)

    2010-02-01

    Antiproliferative actions of calcitriol have been shown to occur in many cell types; however, little is known regarding the molecular basis of this process in breast carcinoma. Ether-a-go-go (Eag1) potassium channels promote oncogenesis and are implicated in breast cancer cell proliferation. Since calcitriol displays antineoplastic effects while Eag1 promotes tumorigenesis, and both factors antagonically regulate cell cycle progression, we investigated a possible regulatory effect of calcitriol upon Eag1 as a mean to uncover new molecular events involved in the antiproliferative activity of this hormone in human breast tumor-derived cells. RT real-time PCR and immunocytochemistry showed that calcitriol suppressed Eag1 expression by a vitamin D receptor (VDR)-dependent mechanism. This effect was accompanied by inhibition of cell proliferation, which was potentiated by astemizole, a nonspecific Eag1 inhibitor. Immunohistochemistry and Western blot demonstrated that Eag1 and VDR abundance was higher in invasive-ductal carcinoma than in fibroadenoma, and immunoreactivity of both proteins was located in ductal epithelial cells. Our results provide evidence of a novel mechanism involved in the antiproliferative effects of calcitriol and highlight VDR as a cancer therapeutic target for breast cancer treatment and prevention.

  5. Calcitriol inhibits Ether-a go-go potassium channel expression and cell proliferation in human breast cancer cells

    International Nuclear Information System (INIS)

    Antiproliferative actions of calcitriol have been shown to occur in many cell types; however, little is known regarding the molecular basis of this process in breast carcinoma. Ether-a-go-go (Eag1) potassium channels promote oncogenesis and are implicated in breast cancer cell proliferation. Since calcitriol displays antineoplastic effects while Eag1 promotes tumorigenesis, and both factors antagonically regulate cell cycle progression, we investigated a possible regulatory effect of calcitriol upon Eag1 as a mean to uncover new molecular events involved in the antiproliferative activity of this hormone in human breast tumor-derived cells. RT real-time PCR and immunocytochemistry showed that calcitriol suppressed Eag1 expression by a vitamin D receptor (VDR)-dependent mechanism. This effect was accompanied by inhibition of cell proliferation, which was potentiated by astemizole, a nonspecific Eag1 inhibitor. Immunohistochemistry and Western blot demonstrated that Eag1 and VDR abundance was higher in invasive-ductal carcinoma than in fibroadenoma, and immunoreactivity of both proteins was located in ductal epithelial cells. Our results provide evidence of a novel mechanism involved in the antiproliferative effects of calcitriol and highlight VDR as a cancer therapeutic target for breast cancer treatment and prevention.

  6. Sulfonation of 17{beta}-estradiol and inhibition of sulfotransferase activity by polychlorobiphenylols and celecoxib in channel catfish, Ictalurus punctatus

    Energy Technology Data Exchange (ETDEWEB)

    Wang Liquan [Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL 32610 (United States); James, Margaret O. [Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL 32610 (United States)]. E-mail: mojames@ufl.edu

    2007-03-10

    The sulfonation of 17{beta}-estradiol (E2) by human liver and recombinant sulfotransferases is influenced by environmental contaminants such as hydroxylated metabolites of polychlorinated biphenyls (OH-PCBs), which are potent inhibitors, and the therapeutic drug, celecoxib, which affects positional sulfonation of E2. In some locations, the aquatic environment is contaminated by PCBs, OH-PCBs and widely used therapeutic drugs. The objectives of this study were to investigate the sulfonation kinetics of E2 in liver cytosol from channel catfish (Ictalurus punctatus); to examine the effect of OH-PCBs on E2 sulfonation; and to determine if celecoxib altered the position of E2 sulfonation, as it does with human liver cytosol. E2 was converted to both 3- and 17-sulfates by catfish liver cytosol. At E2 concentrations below 1{mu}M, formation of E2-3-sulfate (E2-3-S) predominated, but substrate inhibition was observed at higher concentrations. Rates of E2-3-S formation at different E2 concentrations were fit to a substrate inhibition model, with K{sup '}{sub m} and V{sup '}{sub max} values of 0.40+/-0.10{mu}M and 91.0+/-4.7pmol/min/mg protein, respectively and K{sub i} of 1.08+/-0.09{mu}M. The formation of E2-17-S fit Michaelis-Menten kinetics over the concentration range 25nM to 2.5{mu}M, with K{sub m} and V{sub max} values of 1.07+/-0.23{mu}M and 25.7+/-4.43pmol/min/mg protein, respectively. The efficiency (V{sub max}/K{sub m}) of formation of E2-3-S was 9.8-fold higher than that of E2-17-S. Several OH-PCBs inhibited E2 3-sulfonation, measured at an E2 concentration of 1nM. Of those tested, the most potent inhibitor was 4'-OH-CB79, with two chlorine atoms flanking the OH group (IC{sub 50}: 94nM). The inhibition of estrogen sulfonation by OH-PCBs may disrupt the endocrine system and thus contribute to the known toxic effects of these compounds. Celecoxib did not stimulate E2-17-S formation, as is the case with human liver cytosol, but did inhibit the

  7. Inhibition of in vivo [(3)H]MK-801 binding by NMDA receptor open channel blockers and GluN2B antagonists in rats and mice.

    Science.gov (United States)

    Fernandes, Alda; Wojcik, Trevor; Baireddy, Praveena; Pieschl, Rick; Newton, Amy; Tian, Yuan; Hong, Yang; Bristow, Linda; Li, Yu-Wen

    2015-11-01

    N-methyl-D-aspartate (NMDA) receptor antagonists, including open channel blockers and GluN2B receptor subtype selective antagonists, have been developed for the treatment of depression. The current study investigated effects of systemically administered NMDA channel blockers and GluN2B receptor antagonists on NMDA receptor activity in rodents using in vivo [(3)H]MK-801 binding. The receptor occupancy of GluN2B antagonists was measured using ex vivo [(3)H]Ro 25-6981 binding. Ketamine, a NMDA receptor channel blocker, produced a dose/exposure- and time-dependent inhibition of in vivo [(3)H]MK-801 binding that was maximal at ~100%. The complete inhibition of in vivo [(3)H]MK-801 binding was also observed with NMDA receptor channel blockers, AZD6765 (Lanicemine) and MK-801 (Dizocilpine). CP-101,606 (Traxoprodil), a GluN2B antagonist, produced a dose/exposure- and time-dependent inhibition of in vivo [(3)H]MK-801 binding that was maximal at ~60%. Partial inhibition was also observed with other GluN2B antagonists including MK-0657 (CERC-301), EVT-101, Ro 25-6981 and radiprodil. For all GluN2B antagonists tested, partial [(3)H]MK-801 binding inhibition was achieved at doses saturating GluN2B receptor occupancy. Combined treatment with ketamine (10mg/kg, i.p.) and Ro 25-6981(10mg/kg, i.p.) produced a level of inhibition of in vivo [(3)H]MK-801 binding that was similar to treatment with either agent alone. In conclusion, this in vivo [(3)H]MK-801 binding study shows that NMDA receptor activity in the rodent forebrain can be inhibited completely by channel blockers, but only partially (~60%) by GluN2B receptor antagonists. At doses effective in preclinical models of depression, ketamine may preferentially inhibit the same population of NMDA receptors as Ro 25-6981, namely those containing the GluN2B subunit. PMID:26325093

  8. High-fat diet leads to tissue-specific changes reflecting risk factors for diseases in DBA/2J mice

    OpenAIRE

    Hageman, Rachael S.; Wagener, Asja; Hantschel, Claudia; Svenson, Karen L.; Churchill, Gary A; Brockmann, Gudrun A., 1958-

    2010-01-01

    The aim of this study was to characterize the responses of individual tissues to high-fat feeding as a function of mass, fat composition, and transcript abundance. We examined a panel of eight tissues [5 white adipose tissues (WAT), brown adipose tissue (BAT), liver, muscle] obtained from DBA/2J mice on either a standard breeding diet (SBD) or a high-fat diet (HFD). HFD led to weight gain, decreased insulin sensitivity, and tissue-specific responses, including inflammation, in these mice. The...

  9. Role of glycogen-lowering exercise in the change of fat oxidation in response to a high-fat diet.

    OpenAIRE

    Schrauwen, P; van Marken Lichtenbelt, W.D.; SARIS, W.H.M.; Westerterp, K.R.

    1997-01-01

    Department of Human Biology, Maastricht University, The Netherlands. One of the candidate factors for determining the increase of fat oxidation after a switch from a reduced-fat diet to a high-fat diet is the size of the glycogen storage. Therefore, we studied the effect of low glycogen stores on fat oxidation after a switch from a reduced-fat diet to a high-fat diet. Twelve healthy, nonobese males and females (age: 22 +/- 1 yr, body mass index: 21.0 +/- 0.7, maximal power output: 254 +/- 11 ...

  10. Effect of corn gluten and its hydrolysate consumptions on weight reduction in rats fed a high-fat diet

    OpenAIRE

    Kim, Joohee; Park, Juyeon; Hong, Soyoung; Kim, Mi Kyung

    2009-01-01

    This study examined the effects of corn gluten (CG) and its hydrolysate consumptions on weight reduction in rats fed a high-fat diet. Eight-month-old male Sprague-Dawley rats (n=40) were fed a high-fat diet (40% calorie as fat) for 4 weeks. They were then randomly divided into four groups and fed the isocaloric diets with different protein sources for 8 weeks. The protein sources were casein (control group), intact CG (CG group), CG hydrolysate A (CGHA group, 30% of protein as peptides and 70...

  11. Effect of a 1-week, eucaloric, moderately high-fat diet on peripheral insulin sensitivity in healthy premenopausal women

    OpenAIRE

    Branis, Natalia M.; Etesami, Marjan; Walker, Ryan W.; Berk, Evan S; Albu, Jeanine B.

    2015-01-01

    Objectives To determine whether a weight-maintaining, moderate (50%) high-fat diet is deleterious to insulin sensitivity in healthy premenopausal women. Design/setting/participants 23 African-American and non-Hispanic white, healthy, overweight, and obese premenopausal women recruited in New York City, USA, fed either a eucaloric, 1-week long high-fat (50% of total Kcal from fat) diet or a eucaloric, 1-week long low-fat (30% of total Kcal from fat) diet, assigned in a randomized crossover des...

  12. Effects of exercise training on subcutaneous and visceral adipose tissue in normal- and high-fat diet-fed rats

    OpenAIRE

    Gollisch, Katja S.C.; Brandauer, Josef; Jessen, Niels; Toyoda, Taro; Nayer, Ali; Hirshman, Michael F.; Goodyear, Laurie J.

    2009-01-01

    Regular physical activity improves glucose tolerance and decreases adiposity. Our aim was to investigate the effects of exercise training on subcutaneous (inguinal) and visceral (parametrial) adipose tissue in rats that were fed a chow diet (13% fat) or made insulin resistant by a high-fat diet (60% fat). Sprague-Dawley rats performed 4 wk of voluntary wheel running or were kept as sedentary controls. The training groups fed chow and the high-fat diet achieved similar running distances (8.8 ±...

  13. The Characterization of High-Fat Diet and Multiple Low-Dose Streptozotocin Induced Type 2 Diabetes Rat Model

    OpenAIRE

    Ming Zhang; Xiao-Yan Lv; Jing Li; Zhi-Gang Xu; Li Chen

    2008-01-01

    Aim. Based on the previously established method, we developed a better and stable animal model of type 2 diabetes mellitus by high-fat diet combined with multiple low-dose STZ injections. Meanwhile, this new model was used to evaluate the antidiabetic effect of berberine. Method. Wistar male rats fed with regular chow for 4 weeks received vehicle (control groups), rats fed with high-fat diet for 4 weeks received different amounts of STZ once or twice by intraperitoneal injection (diabetic mo...

  14. The relation of high fat diet, metabolic disturbances and brain oxidative dysfunction: modulation by hydroxy citric acid

    OpenAIRE

    Kamel Hamdy H; Amin Kamal A; Abd Eltawab Mohamed A

    2011-01-01

    Abstract Aims This study aimed to examine the effect of high fat diet (HFD) to modulate brain dysfunction, and understand the linkages between obesity, metabolic disturbances and the brain oxidative stress (BOS) dysfunction and modulation with hydroxyl citric acid of G. Cambogia. Methods Rats were divided into 3 groups; 1st control, maintained on standard normal rat chow diet, 2nd HFD, maintained on high fat diet along 12 week and 3rd HFD+G, administered G. Cambogia for 4 weeks and each group...

  15. Maternal High Fat Diet Is Associated with Decreased Plasma n–3 Fatty Acids and Fetal Hepatic Apoptosis in Nonhuman Primates

    OpenAIRE

    Grant, Wilmon F.; Gillingham, Melanie B.; Batra, Ayesha K; Fewkes, Natasha M.; Comstock, Sarah M.; Diana Takahashi; Theodore P Braun; Grove, Kevin L.; FRIEDMAN, Jacob E.; Marks, Daniel L.

    2011-01-01

    To begin to understand the contributions of maternal obesity and over-nutrition to human development and the early origins of obesity, we utilized a non-human primate model to investigate the effects of maternal high-fat feeding and obesity on breast milk, maternal and fetal plasma fatty acid composition and fetal hepatic development. While the high-fat diet (HFD) contained equivalent levels of n-3 fatty acids (FA's) and higher levels of n-6 FA's than the control diet (CTR), we found signific...

  16. A High-Fat Diet Causes Impairment in Hippocampal Memory and Sex-Dependent Alterations in Peripheral Metabolism

    OpenAIRE

    Underwood, Erica L.; Thompson, Lucien T.

    2015-01-01

    While high-fat diets are associated with rising incidence of obesity/type-2 diabetes and can induce metabolic and cognitive deficits, sex-dependent comparisons are rarely systematically made. Effects of exclusive consumption of a high-fat diet (HFD) on systemic metabolism and on behavioral measures of hippocampal-dependent memory were compared in young male and female LE rats. Littermates were fed from weaning either a HFD or a control diet (CD) for 12 wk prior to testing. Sex-different effec...

  17. The effects of Momordica charantia on obesity and lipid profiles of mice fed a high-fat diet

    OpenAIRE

    Wang, Jun; Ryu, Ho Kyung

    2015-01-01

    BACKGROUND/OBJECTIVES The present study was conducted to investigate the effects of dried Momordica charantia aqueous extracts (MCA) and ethanol extracts (MCE) on obesity and lipid profiles in mice fed a high-fat diet. MATERIALS/METHODS Forty two ICR mice were randomly divided into six groups. The normal group was fed a basal diet, and other groups were fed a 45% high-fat diet (HFD) for 7 weeks. The normal and HFD groups were also orally administered distilled water each day for 7 weeks. The ...

  18. Effects of a high-fat diet in health and in Alzheimer’s disease: a gender comparison study

    OpenAIRE

    Antunes Martins, Isaura

    2015-01-01

    The prevalence of obesity is growing worldwide partly due to an increase in consumption of diets high in fat. Obesity is known as a risk factor for developing Alzheimer’s disease (AD) later in life. Both obesity and AD are associated with cognitive deficits and experimental high-fat diets can impair memory in cognitively normal rodents but also worsen memory deficits in AD mouse models. What is still unclear is the molecular mechanisms behind the detrimental effects of a high-fat diet on memo...

  19. Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: A study to assess the drug's cardiac ion channel profile

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, Xaver; Kovar, Michael; Rubi, Lena; Mike, Agnes K.; Lukacs, Peter; Gawali, Vaibhavkumar S.; Todt, Hannes [Center for Physiology and Pharmacology, Department of Neurophysiology and -pharmacology, Medical University of Vienna, 1090 Vienna (Austria); Hilber, Karlheinz, E-mail: karlheinz.hilber@meduniwien.ac.at [Center for Physiology and Pharmacology, Department of Neurophysiology and -pharmacology, Medical University of Vienna, 1090 Vienna (Austria); Sandtner, Walter [Center for Physiology and Pharmacology, Institute of Pharmacology, Medical University of Vienna, 1090 Vienna (Austria)

    2013-12-01

    The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licenced as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channel profile in more detail, we studied the effects of ibogaine and its congener 18-Methoxycoronaridine (18-MC) on various cardiac voltage-gated ion channels. We confirmed that heterologously expressed hERG currents are reduced by ibogaine in low micromolar concentrations. Moreover, at higher concentrations, the drug also reduced human Na{sub v}1.5 sodium and Ca{sub v}1.2 calcium currents. Ion currents were as well reduced by 18-MC, yet with diminished potency. Unexpectedly, although blocking hERG channels, ibogaine did not prolong the action potential (AP) in guinea pig cardiomyocytes at low micromolar concentrations. Higher concentrations (≥ 10 μM) even shortened the AP. These findings can be explained by the drug's calcium channel inhibition, which counteracts the AP-prolonging effect generated by hERG blockade. Implementation of ibogaine's inhibitory effects on human ion channels in a computer model of a ventricular cardiomyocyte, on the other hand, suggested that ibogaine does prolong the AP in the human heart. We conclude that therapeutic concentrations of ibogaine have the propensity to prolong the QT interval of the electrocardiogram in humans. In some cases this may lead to cardiac arrhythmias. - Highlights: • We study effects of anti-addiction drug ibogaine on ionic currents in cardiomyocytes. • We assess the cardiac ion channel profile of ibogaine. • Ibogaine inhibits hERG potassium, sodium and calcium channels. • Ibogaine’s effects on

  20. Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: A study to assess the drug's cardiac ion channel profile

    International Nuclear Information System (INIS)

    The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licenced as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channel profile in more detail, we studied the effects of ibogaine and its congener 18-Methoxycoronaridine (18-MC) on various cardiac voltage-gated ion channels. We confirmed that heterologously expressed hERG currents are reduced by ibogaine in low micromolar concentrations. Moreover, at higher concentrations, the drug also reduced human Nav1.5 sodium and Cav1.2 calcium currents. Ion currents were as well reduced by 18-MC, yet with diminished potency. Unexpectedly, although blocking hERG channels, ibogaine did not prolong the action potential (AP) in guinea pig cardiomyocytes at low micromolar concentrations. Higher concentrations (≥ 10 μM) even shortened the AP. These findings can be explained by the drug's calcium channel inhibition, which counteracts the AP-prolonging effect generated by hERG blockade. Implementation of ibogaine's inhibitory effects on human ion channels in a computer model of a ventricular cardiomyocyte, on the other hand, suggested that ibogaine does prolong the AP in the human heart. We conclude that therapeutic concentrations of ibogaine have the propensity to prolong the QT interval of the electrocardiogram in humans. In some cases this may lead to cardiac arrhythmias. - Highlights: • We study effects of anti-addiction drug ibogaine on ionic currents in cardiomyocytes. • We assess the cardiac ion channel profile of ibogaine. • Ibogaine inhibits hERG potassium, sodium and calcium channels. • Ibogaine’s effects on ion channels are a potential

  1. Polyunsaturated fatty acids inhibit stimulated coupling between the ER Ca(2+) sensor STIM1 and the Ca(2+) channel protein Orai1 in a process that correlates with inhibition of stimulated STIM1 oligomerization.

    Science.gov (United States)

    Holowka, David; Korzeniowski, Marek K; Bryant, Kirsten L; Baird, Barbara

    2014-08-01

    Polyunsaturated fatty acids (PUFAs) have been found to be effective inhibitors of cell signaling in numerous contexts, and we find that acute addition of micromolar PUFAs such as linoleic acid effectively inhibit of Ca(2+) responses in mast cells stimulated by antigen-mediated crosslinking of FcεRI or by the SERCA pump inhibitor, thapsigargin. In contrast, the saturated fatty acid, stearic acid, with the same carbon chain length as linoleic acid does not inhibit these responses. Consistent with this inhibition of store-operated Ca(2+) entry (SOCE), linoleic acid inhibits antigen-stimulated granule exocytosis to a similar extent. Using the fluorescently labeled plasma membrane Ca(2+) channel protein, AcGFP-Orai1, together with the labeled ER Ca(2+) sensor protein, STIM1-mRFP, we monitor stimulated coupling of these proteins that is essential for SOCE with a novel spectrofluorimetric resonance energy transfer method. We find effective inhibition of this stimulated coupling by linoleic acid that accounts for the inhibition of SOCE. Moreover, we find that linoleic acid induces some STIM1-STIM1 association, while inhibiting stimulated STIM1 oligomerization that precedes STIM1-Orai1 coupling. We hypothesize that linoleic acid and related PUFAs inhibit STIM1-Orai1 coupling by a mechanism that involves perturbation of ER membrane structure, possibly by disrupting electrostatic interactions important in STIM1 oligomerization. Thisarticle is part of a Special Issue entitled Tools to study lipid functions. PMID:24769339

  2. The class III anti-arrhythmic agent, amiodarone, inhibits voltage-dependent K(+) channels in rabbit coronary arterial smooth muscle cells.

    Science.gov (United States)

    Li, Hongliang; Kim, Han Sol; Kim, Hye Won; Shin, Sung Eun; Jung, Won-Kyo; Ha, Kwon-Soo; Han, Eun-Taek; Hong, Seok-Ho; Firth, Amy L; Bae, Young Min; Choi, Il-Whan; Park, Won Sun

    2016-07-01

    We examined the inhibitory effect of amiodarone, a class III anti-arrhythmic agent, on voltage-dependent K(+) (Kv) currents in freshly isolated rabbit coronary arterial smooth muscle cells, using a whole-cell patch clamp technique. Amiodarone inhibited Kv currents in a concentration-dependent manner, with a half-maximal inhibitory concentration (IC50) value of 3.9 ± 1.44 μM and a Hill coefficient of 0.45 ± 0.14. Amiodarone did not have a significant effect on the steady-state activation of Kv channels, but shifted the inactivation current toward a more negative potential. Application of consecutive pulses progressively augmented the amiodarone-induced Kv channel inhibition. Another class III anti-arrhythmic agent, dofetilide, did not inhibit the Kv current or change the inhibitory effect of amiodarone on Kv channels. Therefore, these results strongly suggest that amiodarone inhibits Kv currents in a concentration- and state-dependent manner. PMID:27030392

  3. GABA/sub B/ receptor activation inhibits Ca/sup 2 +/-activated potassium channels in synaptosomes: involvement of G-proteins

    Energy Technology Data Exchange (ETDEWEB)

    Ticku, M.K.; Delgado, A.

    1989-01-01

    /sup 86/Rb-efflux assay from preloaded synaptosomes of rat cerebral cortex was developed to study the effect of GABA/sub B/ receptor agonist baclofen on Ca/sup 2 +/-activated K/sup +/-channels. Depolarization of /sup 86/Rb-loaded synaptosomes in physiological buffer increased Ca/sup 2 +/-activated /sup 86/Rb-efflux by 400%. The /sup 86/Rb-efflux was blocked by quinine sulfate, tetraethylammonium, and La/sup 3 +/ indicating the involvement of Ca/sup 2 +/-activated K/sup +/-channels. (-)Baclofen inhibited Ca/sup 2 +/-activated /sup 86/Rb-efflux in a stereospecific manner. The inhibitory effect of (-)baclofen was mediated by GABA/sub B/ receptor activation, since it was blocked by GABA/sub B/ antagonist phaclofen, but not by bicuculline. Further, pertussis toxin also blocked the ability of baclofen or depolarizing action to affect Ca/sup 2 +/-activated K/sup +/-channels. These results suggest that baclofen inhibits Ca/sup 2 +/-activated K/sup +/-channels in synaptosomes and these channels are regulated by G-proteins. This assay may provide an ideal in vitro model to study GABA/sub B/ receptor pharmacology.

  4. Effect of Myostatin Depletion on Weight Gain, Hyperglycemia, and Hepatic Steatosis during Five Months of High-Fat Feeding in Mice

    OpenAIRE

    Burgess, Kerri; Xu, Tianshun; Brown, Roger; Han, Bajin; Welle, Stephen

    2011-01-01

    The marked hypermuscularity in mice with constitutive myostatin deficiency reduces fat accumulation and hyperglycemia induced by high-fat feeding, but it is unclear whether the smaller increase in muscle mass caused by postdevelopmental loss of myostatin activity has beneficial metabolic effects during high-fat feeding. We therefore examined how postdevelopmental myostatin knockout influenced effects of high-fat feeding. Male mice with ubiquitous expression of tamoxifen-inducible Cre recombin...

  5. Evidence for a novel functional role of astrocytes in the acute homeostatic response to high-fat diet intake in mice

    OpenAIRE

    Buckman, Laura B.; Thompson, Misty M.; Lippert, Rachel N.; Blackwell, Timothy S.; Yull, Fiona E.; Ellacott, Kate L. J.

    2014-01-01

    Objective Introduction of a high-fat diet to mice results in a period of voracious feeding, known as hyperphagia, before homeostatic mechanisms prevail to restore energy intake to an isocaloric level. Acute high-fat diet hyperphagia induces astrocyte activation in the rodent hypothalamus, suggesting a potential role of these cells in the homeostatic response to the diet. The objective of this study was to determine physiologic role of astrocytes in the acute homeostatic response to high-fat f...

  6. Abdominal Fat Accumulation with Hyperuricemia and Hypercholesterolemia Quail Model Induced by High Fat Diet

    Institute of Scientific and Technical Information of China (English)

    Zhi-jian Lin; Bing Zhang; Xiao-qing Liu; Hong-lian Yang

    2009-01-01

    Objective To establish abdominal fat accumulation with hyperuricemia and hypercholesterolemia quail model fed with high fat diet.And then to investigate the pathological characteristics of this quail model.Methods Thirty Longcheng quails were randomly divided into two groups:control group and model group(n=15).The control group quails were fed with normal diet and model group quails were fed with high fat diet for 14 days.After a 12-hour overnight fast,liver and abdominal fat at euthanasia as well as serum were collected.The levels of serum uric acid,total cholesterol,high density lipoprotein cholesterol (HDL-C),low density lipoprotein cholesterol(LDL-C),triglyceride,free fatty acid(FFA),and blood glucose were assayed.The activity changes of adenosine deaminase(ADA),xanthine oxidase(XOD),lipoprotein lipase(LPL),hepatic lipase(HL),and fatty acid synthetase(FAS)were analyzed.Results Comparcd with control group,the abdominal fat content(0.74±0.63 vs.1.36±0.65 g,P<0.05)and abdominal fat index(0.44% ±0.30% vs.0.85% ±0.30% ,P<0.01)as well as live lipid index (3.61% ±0.65% vs.11.33% ±2.14% ,P<0.01)in model group significantly increased;the levels of serum uric acid(210.61±94.76 vs.304.25±141.94 μmol/L,P<0.05),total cholesterol(4.20±0.51 vs.20.10±11.25 mmol/L,P<0.01),LDL-C(1.16±0.29 vs.10.78±6.48 mmol/L,P<0.01),and FFA(0.39±0.14 vs.0.55±0.15 mmol/L,P<0.01)in model group significantly increased;HDL-C(5.85±0.95 vs.4.14±2.03mmol/L,P<0.05)significantly decreased;the levels of triglyceride and blood glucose had no significant changes(P>0.05);the activities of ADA(9.71±3.05 vs.17.19±5.10 U/ml,P<0.01)and XOD(10.58±6.88vs.19.22±9.44 U/L,P<0.01)in model group significantly increased;and FAS,LPL,HL had no significant changes(P>0.05).Conclusions High fat diet can induce abdominal fat accumulation with hyperuricemia and hypercholesterolemia quail model.The changes of uric acid and lipid metabolic enzyme activities may be the pathological

  7. High Caloric Diet for ALS Patients: High Fat, High Carbohydrate or High Protein

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    Sarvin Sanaie

    2015-01-01

    . They showed that patients in the highcarbohydrate/high-calorie groups gained 0.39 kg more weight per month, compared with 0.11kg per month in the control group, and there was an average weight loss of 0.46 kg per month in the high-fat/high-calorie group. However, there are some concerns that highcarbohydrate low-fat diets might increase the risk of ALS and these findings should be interpreted with caution (4. Furthermore, according to Wills et al. high fat-high caloric diets could not be ideal regimens for these patients due to the associated gastrointestinal complications (3. Dorst and associates, in their study, showed that high caloric food supplement with high fat is suitable to establish body weight compared to high carbohydrate formula. Hence, it seems that high protein-high caloric diets could be more appropriate options for both improving negative nitrogen balance and decreasing muscle atrophy in patients with ALS based on the pathophysiology of proteinenergy malnutrition and hypermetabolism which is thought to be due to mitochondria problem. The multifactorial pathophysiology of ALS has resulted in hypotheses that there may be subgroups of patients, eventually defined by a specific underlying etiology or clinical presentation, which selectively respond to a particular regimen. Consequently, further RCTs with larger sample size are required to clarify the best regimen for weight gain and improved survival in ALS patients and it seems that personalized nutritional support or combined regimens might be the best way and could improve the quality of life considering the complex pathophysiology of malnutrition.

  8. Effect of Ginseng (Panax ginseng) Berry EtOAc Fraction on Cognitive Impairment in C57BL/6 Mice under High-Fat Diet Inducement

    OpenAIRE

    Chang Hyeon Park; Seon Kyeong Park; Tae Wan Seung; Dong Eun Jin; Tianjiao Guo; Ho Jin Heo

    2015-01-01

    High-fat diet-induced obesity leads to type 2 diabetes. Recently, there has been growing apprehension about diabetes-associated cognitive impairment (DACM). The effect of ginseng (Panax ginseng) berry ethyl acetate fraction (GBEF) on mice with high-fat diet-induced cognitive impairment was investigated to confirm its physiological function. C57BL/6 mice were fed a high-fat diet for 5 weeks and then a high-fat diet with GBEF (20 and 50 mg/kg of body weight) for 4 weeks. After three in vivo beh...

  9. Nrf2 deficiency improves glucose tolerance in mice fed a high-fat diet

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu-Kun Jennifer; Wu, Kai Connie; Liu, Jie; Klaassen, Curtis D., E-mail: cklaasse@kumc.edu

    2012-11-01

    Nrf2, a master regulator of intracellular redox homeostasis, is indicated to participate in fatty acid metabolism in liver. However, its role in diet-induced obesity remains controversial. In the current study, genetically engineered Nrf2-null, wild-type (WT), and Nrf2-activated, Keap1-knockdown (K1-KD) mice were fed either a control or a high-fat Western diet (HFD) for 12 weeks. The results indicate that the absence or enhancement of Nrf2 activity did not prevent diet-induced obesity, had limited effects on lipid metabolism, but affected blood glucose homeostasis. Whereas the Nrf2-null mice were resistant to HFD-induced glucose intolerance, the Nrf2-activated K1-KD mice exhibited prolonged elevation of circulating glucose during a glucose tolerance test even on the control diet. Feeding a HFD did not activate the Nrf2 signaling pathway in mouse livers. Fibroblast growth factor 21 (Fgf21) is a liver-derived anti-diabetic hormone that exerts glucose- and lipid-lowering effects. Fgf21 mRNA and protein were both elevated in livers of Nrf2-null mice, and Fgf21 protein was lower in K1-KD mice than WT mice. The inverse correlation between Nrf2 activity and hepatic expression of Fgf21 might explain the improved glucose tolerance in Nrf2-null mice. Furthermore, a more oxidative cellular environment in Nrf2-null mice could affect insulin signaling in liver. For example, mRNA of insulin-like growth factor binding protein 1, a gene repressed by insulin in hepatocytes, was markedly elevated in livers of Nrf2-null mice. In conclusion, genetic alteration of Nrf2 does not prevent diet-induced obesity in mice, but deficiency of Nrf2 improves glucose homeostasis, possibly through its effects on Fgf21 and/or insulin signaling. -- Highlights: ► Nrf2 deficiency improves glucose tolerance in mice fed a high-fat diet. ► The anti-diabetic hormone, Fgf21, is highly expressed in livers of Nrf2-null mice. ► The absence of Nrf2 increases the insulin-regulated Igfbp-1 mRNA in liver.

  10. Nrf2 deficiency improves glucose tolerance in mice fed a high-fat diet

    International Nuclear Information System (INIS)

    Nrf2, a master regulator of intracellular redox homeostasis, is indicated to participate in fatty acid metabolism in liver. However, its role in diet-induced obesity remains controversial. In the current study, genetically engineered Nrf2-null, wild-type (WT), and Nrf2-activated, Keap1-knockdown (K1-KD) mice were fed either a control or a high-fat Western diet (HFD) for 12 weeks. The results indicate that the absence or enhancement of Nrf2 activity did not prevent diet-induced obesity, had limited effects on lipid metabolism, but affected blood glucose homeostasis. Whereas the Nrf2-null mice were resistant to HFD-induced glucose intolerance, the Nrf2-activated K1-KD mice exhibited prolonged elevation of circulating glucose during a glucose tolerance test even on the control diet. Feeding a HFD did not activate the Nrf2 signaling pathway in mouse livers. Fibroblast growth factor 21 (Fgf21) is a liver-derived anti-diabetic hormone that exerts glucose- and lipid-lowering effects. Fgf21 mRNA and protein were both elevated in livers of Nrf2-null mice, and Fgf21 protein was lower in K1-KD mice than WT mice. The inverse correlation between Nrf2 activity and hepatic expression of Fgf21 might explain the improved glucose tolerance in Nrf2-null mice. Furthermore, a more oxidative cellular environment in Nrf2-null mice could affect insulin signaling in liver. For example, mRNA of insulin-like growth factor binding protein 1, a gene repressed by insulin in hepatocytes, was markedly elevated in livers of Nrf2-null mice. In conclusion, genetic alteration of Nrf2 does not prevent diet-induced obesity in mice, but deficiency of Nrf2 improves glucose homeostasis, possibly through its effects on Fgf21 and/or insulin signaling. -- Highlights: ► Nrf2 deficiency improves glucose tolerance in mice fed a high-fat diet. ► The anti-diabetic hormone, Fgf21, is highly expressed in livers of Nrf2-null mice. ► The absence of Nrf2 increases the insulin-regulated Igfbp-1 mRNA in liver.

  11. Ameliorative Effect of Hexane Extract of Phalaris canariensis on High Fat Diet-Induced Obese and Streptozotocin-Induced Diabetic Mice

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    Rosa Martha Perez Gutierrez

    2014-01-01

    Full Text Available Obesity is one of the major factors to increase various disorders like diabetes. The present paper emphasizes study related to the antiobesity effect of Phalaris canariensis seeds hexane extract (Al-H in high-fat diet- (HFD- induced obese CD1 mice and in streptozotocin-induced mild diabetic (MD and severely diabetic (SD mice.AL-H was orally administered to MD and SD mice at a dose of 400 mg/kg once a day for 30 days, and a set of biochemical parameters were studied: glucose, cholesterol, triglycerides, lipid peroxidation, liver and muscle glycogen, ALP, SGOT, SGPT, glucose-6-phosphatase, glucokinase, hexokinase, SOD, CAT, GSH, GPX activities, and the effect on insulin level. HS-H significantly reduced the intake of food and water and body weight loss as well as levels of blood glucose, serum cholesterol, triglyceride, lipoprotein, oxidative stress, showed a protective hepatic effect, and increased HDL-cholesterol, serum insulin in diabetic mice. The mice fed on the high-fat diet and treated with AL-H showed inhibitory activity on the lipid metabolism decreasing body weight and weight of the liver and visceral adipose tissues and cholesterol and triglycerides in the liver. We conclude that AL-H can efficiently reduce serum glucose and inhibit insulin resistance, lipid abnormalities, and oxidative stress in MD and SD mice. Our results demonstrate an antiobesity effect reducing lipid droplet accumulation in the liver, indicating that its therapeutic properties may be due to the interaction plant components soluble in the hexane extract, with any of the multiple targets involved in obesity and diabetes pathogenesis.

  12. STUDY OF THE ANTIHYPERLIPIDEMIC, ANTIOXIDATIVE AND ANTIATHEROGENIC ACTIVITY OF TRITICUM AESTIVUM LINN. IN RABBIT RECEIVING HIGH FAT DIET

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    Das Swarnamoni

    2012-10-01

    Full Text Available The aim was to study of the antihyperlipidemic, antioxidative and antiatherogenic activity of Triticum aestivum Linn. in rabbit receiving high fat diet. Twenty rabbits of either sex were taken and divided into four groups five in each as - Normal Control- received normal diet, Hyperlipidemic control- received high fat diet, Test drug group - received high fat diet plus ethanolic extract of Triticum aestivum 500 mg/Kg /day orally and Standard Drug group- received high fat diet plus Atorvastatin 2.1 mg/Kg/day orally for 12 weeks and then animals were sacrificed. Blood sample were collected and lipid profile, catalase, superoxide dismutase and malondialdehyde levels were measured. The antiatherogenic effect was examined by histopathology of aorta. Data were statistically analysed by one way ANOVA followed by Dunnett’s multiple comparison test. Triticum aestivum significantly decreased serum lipids towards normal levels. It also increases catalase and superoxide dismutase activity and decreases malondialdehyde level and histopathological examination revealed prevention of atherosclerosis. Triticum aestivum has antihyperlipidemic, antioxidant and anti atherogenic effects.

  13. Eicosapentaenoic acid prevents high fat diet-induced metabolic disorders: Genomic and metabolomic analyses of underlying mechanism

    Science.gov (United States)

    Previously our lab demonstrated eicosapenaenoic acid (EPA)'s ability to prevent high-fat (HF) diet-induced obesity by decreasing insulin resistance, glucose intolerance and inflammation. In the current study, we used genomic and metabolomic approaches to further investigate the molecular basis for t...

  14. Mulberry ethanol extract attenuates hepatic steatosis and insulin resistance in high-fat diet-fed mice.

    Science.gov (United States)

    Song, Haizhao; Lai, Jia; Tang, Qiong; Zheng, Xiaodong

    2016-07-01

    Nonalcoholic fatty liver disease is one of the most common complications of obesity. Mulberry is an important source of phytochemicals, such as anthocyanins, polyphenols and flavonoids, which are related to its antioxidant activity. In this study, we developed a hypothesis that mulberry exerted beneficial effects on metabolic disorders and evaluated the influence of the mulberry ethanol extract (MEE) on high-fat diet-induced hepatic steatosis and insulin resistance in mice. Thirty-six male C57BL/6J mice were assigned into 3 groups and fed either a low-fat diet or a high-fat diet with or without supplementation with MEE. Our results showed that administration of MEE reduced diet-induced body weight gain, improved high-fat diet-induced hepatic steatosis and adipose hypertrophy, alleviated insulin resistance, and improved glucose homeostasis. Analysis of hepatic gene expression indicated that MEE treatment changed the expression profile of genes involved in lipid and cholesterol metabolism. In conclusion, the present study demonstrated that MEE supplementation protected mice from high-fat diet-induced obesity, hepatic steatosis, and insulin resistance. Moreover, the protective effects of MEE were associated with the induction of fatty acid oxidation and decreased fatty acid and cholesterol biosynthesis. PMID:27262537

  15. The effect of eight weeks endurance training and high-fat diet on appetite-regulating hormones in rat plasma

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    Rouhollah Haghshenas

    2014-04-01

    Full Text Available Objective(s:Consumption of high-fat foods is one of the major causes of obesity. Physical exercise is a strategy used to counteract obesity. The aim of this study was to investigate the effect of eight weeks endurance training and high-fat diet (HFD on appetite-regulating hormones in rat plasma. Materials and Methods:Twenty eight male Wistar rats were randomly divided into four groups: Control group with standard diet (CSD, endurance training with a standard diet (ESD, control group with high-fat diet (CHFD and endurance training with high-fat diet (EHFD. Twenty-four hr after the last training session, the blood samples were obtained and analyzed for hormones levels. Results: The significant increased weight gain and food intake and decreased plasma nesfatin-1 and PYY3-36 levels were observed in CHFD group, while exercise under the HFD antagonized these effects. There were no significant changes in ghrelin, insulin and leptin levels in different groups. Conclusion: These results suggest that exercise can prevent fattening effect of HFD. Probably, performing exercise makes a reduction of food intake and weight gain in rat via the increase in nesfatin-1 and PYY levels. However, further studies are necessary to understand the exact mechanisms involved in this field.

  16. Antihyperlipidemic and antiatherogenic activities of Terminalia pallida Linn. fruits in high fat diet-induced hyperlipidemic rats

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    M T Sampathkumar

    2011-01-01

    Full Text Available Hyperlipidemia contributes significantly in the manifestation and development of atherosclerosis and coronary heart disease (CHD. Although synthetic lipid-lowering drugs are useful in treating hyperlipidemia, there are number of adverse effects. So the current interest has stimulated the search for new lipid-lowering agents with minimal side effects from natural sources. The present study was designed to investigate the antihyperlipidemic and antiatherogenic potentiality of ethanolic extract of Terminalia pallida fruits in high fat diet-induced hyperlipidemic rats. T. pallida fruits ethanolic extract (TPEt was prepared using Soxhlet apparatus. Sprague-Dawley male rats were made hyperlipidemic by giving high fat diet, supplied by NIN (National Institute of Nutrition, Hyderabad, India. TPEt was administered in a dose of 100 mg/kg.b.w./day for 30 days in high fat diet-induced hyperlipidemic rats. The body weights, plasma lipid, and lipoprotein levels were measured before and after the treatment. TPEt showed significant antihyperlipidemic and antiatherogenic activities as evidenced by significant decrease in plasma total cholesterol, triglycerides, low-density lipoprotein cholesterol, and very low-density lipoprotein cholesterol levels coupled together with elevation of high-density lipoprotein cholesterol levels and diminution of atherogenic index in high fat diet-induced hyperlipidemic rats. There was a significantly reduced body weight gain in TPEt-treated hyperlipidemic rats than in the control group. The present study demonstrates that TPEt possesses significant antihyperlipidemic and antiatherogenic properties, thus suggesting its beneficial effect in the treatment of cardiovascular diseases.

  17. Mori Folium and Mori Fructus Mixture Attenuates High-Fat Diet-Induced Cognitive Deficits in Mice

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    Hyo Geun Kim

    2015-01-01

    Full Text Available Obesity has become a global health problem, contributing to various diseases including diabetes, hypertension, cancer, and dementia. Increasing evidence suggests that obesity can also cause neuronal damage, long-term memory loss, and cognitive impairment. The leaves and the fruits of Morus alba L., containing active phytochemicals, have been shown to possess antiobesity and hypolipidemic properties. Thus, in the present study, we assessed their effects on cognitive functioning in mice fed a high-fat diet by performing immunohistochemistry, using antibodies against c-Fos, synaptophysin, and postsynaptic density protein 95 and a behavioral test. C57BL/6 mice fed a high-fat diet for 21 weeks exhibited increased body weight, but mice coadministered an optimized Mori Folium and Mori Fructus extract mixture (2 : 1; MFE for the final 12 weeks exhibited significant body weight loss. Additionally, obese mice exhibited not only reduced neural activity, but also decreased presynaptic and postsynaptic activities, while MFE-treated mice exhibited recovery of these activities. Finally, cognitive deficits induced by the high-fat diet were recovered by cotreatment with MFE in the novel object recognition test. Our findings suggest that the antiobesity effects of MFE resulted in recovery of the cognitive deficits induced by the high-fat diet by regulation of neural and synaptic activities.

  18. Detrimental effects of a high fat/high cholesterol diet on memory and hippocampal markers in aged rats.

    Science.gov (United States)

    Ledreux, Aurélie; Wang, Xiuzhe; Schultzberg, Marianne; Granholm, Ann-Charlotte; Freeman, Linnea R

    2016-10-01

    High fat diets have detrimental effects on cognitive performance, and can increase oxidative stress and inflammation in the brain. The aging brain provides a vulnerable environment to which a high fat diet could cause more damage. We investigated the effects of a high fat/high cholesterol (HFHC) diet on cognitive performance, neuroinflammation markers, and phosphorylated Tau (p-Tau) pathological markers in the hippocampus of Young (4-month old) versus Aged (14-month old) male rats. Young and Aged male Fisher 344 rats were fed a HFHC diet or a normal control diet for 6 months. All animals underwent cognitive testing for 12days in a water radial arm maze to assess spatial and working reference memory. Hippocampal tissue was analyzed by immunohistochemistry for structural changes and inflammation, and Western blot analysis. Young and Aged rats fed the HFHC diet exhibited worse performance on a spatial working memory task. They also exhibited significant reduction of NeuN and calbindin-D28k immunoreactivity as well as an increased activation of microglial cells in the hippocampal formation. Western blot analysis of the hippocampus showed higher levels of p-Tau S202/T205 and T231 in Aged HFHC rats, suggesting abnormal phosphorylation of Tau protein following the HFHC diet exposure. This work demonstrates HFHC diet-induced cognitive impairment with aging and a link between high fat diet consumption and pathological markers of Alzheimer's disease. PMID:27343935

  19. Effect of a genetic locus on rat chromosome 20 on metabolic rate in high-fat diet-induced obesity

    Czech Academy of Sciences Publication Activity Database

    Hojná, S.; Lotfipour, S.; Kuneš, Jaroslav; Křen, V.; Pravenec, M.; Pausová, Z.

    Fyziologický ústav AV ČR, v. v. i.. Roč. 57, č. 3 (2008), 46P-46P ISSN 0862-8408. [International SHR Meeting /13./. 20.06.2008-22.06.2008, Praha] Institutional research plan: CEZ:AV0Z50110509 Keywords : cpo1 * rat chromosome 20 * high-fat diet * obesity Subject RIV: ED - Physiology

  20. Soy protein is beneficial but high-fat diet and voluntary running are detrimental to bone structure in mice

    Science.gov (United States)

    We investigated the effects of diet (AIN93G or high-fat), physical activity (sedentary or voluntary running) and protein source (casein or soy protein isolate) and their interactions on bone microstructural changes in distal femurs in male C57BL/6 mice by using micro-computed tomography. After 14 w...

  1. SOCS2 deletion protects against hepatic steatosis but worsens insulin resistance in high-fat-diet-fed mice

    DEFF Research Database (Denmark)

    Zadjali, Fahad; Santana-Farre, Ruyman; Vesterlund, Mattias;

    2012-01-01

    in the development of diet-induced hepatic steatosis and insulin resistance. SOCS2-knockout (SOCS2(-/-)) mice and wild-type littermates were fed for 4 mo with control or high-fat diet, followed by assessment of insulin sensitivity, hepatic lipid content, and expression of inflammatory cytokines. SOCS2(-/-) mice...

  2. Isoenergetic feeding of low carbohydrate-high fat diets does not increase brown adipose tissue thermogenic capacity in rats.

    Directory of Open Access Journals (Sweden)

    Matthias J Betz

    Full Text Available UNLABELLED: Low-carbohydrate, high-fat (LC-HF diets are popular for inducing weight loss in overweighed adults. Adaptive thermogenesis increased by specific effects of macronutrients on energy expenditure has been postulated to induce this weight loss. We studied brown adipose tissue (BAT morphology and function following exposure to different LC-HF diets. METHODS: Male Wistar rats were fed a standard control diet ad libitum or pair-fed isoenergetic amounts of three experimental diets for 4 weeks. The diets had the following macronutrient composition (% metabolizable energy: carbohydrates, fat, protein: control (64.3/16.7/19, LC-HF-low protein (LC-HF-LP, 1.7/92.8/5.5, LC-HF-normal-protein (LC-HF-NP, 2.2/78.7/19.1, and a high fat diet with carbohydrates ("high fat", 19.4/61.9/18.7. RESULTS: Body weight gain was reduced in all pair-fed experimental groups as compared to rats fed the control diet, with more pronounced effect in rats on LC-HF diets than on the high fat diet with carbohydrates. High fat diets increased expression of PGC1α and ADRB3 in BAT indicating higher SNS outflow. However, UCP1 mRNA expression and expression of UCP1 assessed by immunohistochemistry was not different between diet groups. In accordance, analysis of mitochondrial function in-vitro by extracellular flux analyser (Seahorse Bioscience and measurement of inducible thermogenesis in vivo (primary endpoint, explored by indirect calorimetry following norepinephrine injection, did not show significant differences between groups. Histology of BAT revealed increased lipid droplet size in rats fed the high-fat diet and both LC-HF diets. CONCLUSION: All experimental diets upregulated expression of genes which are indicative for increased BAT activity. However, the functional measurements in vivo revealed no increase of inducible BAT thermogenesis. This indicates that lower body weight gain with LC-HF diets and a high fat diet in a pair-feeding setting is not caused by

  3. Hypothalamic Leptin Gene Therapy Reduces Bone Marrow Adiposity in ob/ob Mice Fed Regular and High-Fat Diets.

    Science.gov (United States)

    Lindenmaier, Laurence B; Philbrick, Kenneth A; Branscum, Adam J; Kalra, Satya P; Turner, Russell T; Iwaniec, Urszula T

    2016-01-01

    Low bone mass is often associated with elevated bone marrow adiposity. Since osteoblasts and adipocytes are derived from the same mesenchymal stem cell (MSC) progenitor, adipocyte formation may increase at the expense of osteoblast formation. Leptin is an adipocyte-derived hormone known to regulate energy and bone metabolism. Leptin deficiency and high-fat diet-induced obesity are associated with increased marrow adipose tissue (MAT) and reduced bone formation. Short-duration studies suggest that leptin treatment reduces MAT and increases bone formation in leptin-deficient ob/ob mice fed a regular diet. Here, we determined the long-duration impact of increased hypothalamic leptin on marrow adipocytes and osteoblasts in ob/ob mice following recombinant adeno-associated virus (rAAV) gene therapy. Eight- to 10-week-old male ob/ob mice were randomized into four groups: (1) untreated, (2) rAAV-Lep, (3) rAAV-green fluorescent protein (rAAV-GFP), or (4) pair-fed to rAAV-Lep. For vector administration, mice were injected intracerebroventricularly with either rAAV-leptin gene therapy (rAAV-Lep) or rAAV-GFP (9 × 10(7) particles) and maintained for 30 weeks. In a second study, the impact of increased hypothalamic leptin levels on MAT was determined in mice fed high-fat diets; ob/ob mice were randomized into two groups and treated with either rAAV-Lep or rAAV-GFP. At 7 weeks post-vector administration, half the mice in each group were switched to a high-fat diet for 8 weeks. Wild-type (WT) controls included age-matched mice fed regular or high-fat diet. High-fat diet resulted in a threefold increase in MAT in WT mice, whereas MAT was increased by leptin deficiency up to 50-fold. Hypothalamic leptin gene therapy increased osteoblast perimeter and osteoclast perimeter with minor change in cancellous bone architecture. The gene therapy decreased MAT levels in ob/ob mice fed regular or high-fat diet to values similar to WT mice fed regular diet. These findings suggest

  4. Calcium Occupancy of N-terminal Sites within Calmodulin Induces Inhibition of the Ryanodine Receptor Calcium Release Channel

    Energy Technology Data Exchange (ETDEWEB)

    Boschek, Curt B; Jones, Terry E; Squier, Thomas C; Bigelow, Diana J

    2007-08-01

    Calmodulin (CaM) regulates calcium release from intracellular stores in skeletal muscle through its association with the ryanodine receptor (RyR1) calcium release channel, where CaM association enhances channel opening at resting calcium levels and its closing at micromolar calcium levels associated with muscle contraction. A high-affinity CaM-binding sequence (RyRp) has been identified in RyR1, which corresponds to a 30-residue sequence (i.e., K3614 – N3643) located within the central portion of the primary sequence. However, it is currently unclear whether the identified CaM-binding sequence a) senses calcium over the physiological range of calcium-concentrations associated with RyR1 regulation or b) plays a structural role unrelated to the calcium-dependent modulation of RyR1 function. Therefore, we have measured the calcium-dependent activation of the individual domains of CaM in association with RyRp and their relationship to the CaM-dependent regulation of RyR1. These measurements utilize an engineered CaM, permitting the site-specific incorporation of N-(1-pyrene) maleimide at either T34C (PyN-CaM) or T110C (PyC-CaM) in the N- and C-domains, respectively. Consistent with prior measurements, we observe a high-affinity association between both apo- and calcium-activated CaM and RyRp. Upon association with RyRp, fluorescence changes in PyN-CaM or PyC-CaM permit the measurement of the calcium-activation of these individual domains. Fluorescence changes upon calcium-activation of PyC-CaM in association with RyRp are indicative of high-affinity calcium-dependent activation of the C-terminal domain of CaM bound to RyRp at resting calcium levels and the activation of the N-terminal domain at levels of calcium associated cellular activation. In comparison, occupancy of calcium-binding sites in the N-domain of CaM mirrors the calcium-dependence of RyR1 inhibition observed at activating calcium levels, where [Ca]1/2 = 4.3 0.4 μM, suggesting a direct regulation of Ry

  5. Quercetin alleviates inflammation after short-term treatment in high-fat-fed mice.

    Science.gov (United States)

    Das, Nilanjan; Sikder, Kunal; Bhattacharjee, Surajit; Majumdar, Suchandra Bhattacharya; Ghosh, Santinath; Majumdar, Subrata; Dey, Sanjit

    2013-06-01

    Consumption of a high-fat diet (HFD) promotes reactive oxygen species (ROS) which ultimately trigger inflammation. The aim of this study was to investigate the role of Moringa oleifera leaf extract (MoLE) and its active component quercetin in preventing NF-κB-mediated inflammation raised by short-term HFD. Quercetin was found to be one of the major flavonoid components from HPLC of MoLE. Swiss mice were fed for 15 days on HFD, both with or without MoLE/quercetin. The antioxidant profile was estimated from liver homogenate. NF-κB and some relevant inflammatory markers were evaluated by immunoblotting, RT-PCR and ELISA. Significantly (P < 0.05) lower antioxidant profile and higher lipid peroxidation was found in HFD group compared to control (P < 0.05). Increased nuclear import of NF-κB and elevated expressions of pro-inflammatory markers were further manifestations in the HFD group. All these changes were reversed in the MoLE/quercetin-treated groups with significant improvement of antioxidant activity compared to the HFD group. MoLE was found to be rich in polyphenols and both MoLE and quercetin showed potent free radical and hydroxyl radical quenching activity. Thus, the present study concluded that short-term treatment with MoLE and its constituent quercetin prevent HFD-mediated inflammation in mice. PMID:23644882

  6. (-)-Epicatechin improves insulin sensitivity in high fat diet-fed mice.

    Science.gov (United States)

    Cremonini, Eleonora; Bettaieb, Ahmed; Haj, Fawaz G; Fraga, Cesar G; Oteiza, Patricia I

    2016-06-01

    Obesity constitutes a major public health concern, being frequently associated with type 2 diabetes (T2D). Evidence from studies in humans and experimental animals suggest that consumption of the flavan-3-ol (-)-epicatechin (EC) and of EC-rich foods may improve insulin sensitivity. To further understand the potential benefits of dietary EC consumption on insulin resistance, this study investigated the capacity of EC supplementation to prevent high fat diet (HFD)-induced insulin resistance in mice. To assess the underlying mechanisms, the effects of HFD and EC consumption on the activation of the insulin cascade and of its negative modulators were evaluated. HFD consumption for 15 w caused obesity and insulin resistance in C57BL/6J mice as evidenced by high fasted and fed plasma glucose and insulin levels, and impaired ITT and GTT tests. This was associated with alterations in the activation of components of the insulin-triggered signaling cascade (insulin receptor, IRS1, ERK1/2, Akt) in adipose and liver tissues. EC supplementation prevented/ameliorated all these parameters. EC acted improving insulin sensitivity in the HFD-fed mice in part through a downregulation of the inhibitory molecules JNK, IKK, PKC and protein tyrosine phosphatase 1B (PTP1B). Thus, the above results suggest that consumption of EC-rich foods could constitute a dietary strategy to mitigate obesity-associated insulin resistance. PMID:26968772

  7. Spent turmeric reduces fat mass in rats fed a high-fat diet.

    Science.gov (United States)

    Han, Kyu-Ho; Lee, Chang-Hyun; Kinoshita, Mikio; Oh, Chan-Ho; Shimada, Ken-Ichiro; Fukushima, Michihiro

    2016-04-20

    Indigestible carbohydrates may improve obesity. Spent turmeric contains high levels of dietary fibre and resistant starch (RS), which have fermentation potential in vitro. We hypothesised that indigestible carbohydrates in spent turmeric might prevent obesity development. In the first study, rats were administered 10% turmeric powder (TP) or spent turmeric powder (STP) in a high-fat (HF) diet for 28 d. In the second study, rats were fed 10% STP in a HF diet with or without antibiotics for 15 d. In the third study, rats were treated with a STP-containing suspension. In study 1, the TP and STP diet increased the caecal short-chain fatty acid (SCFA) content compared to that of a control diet. The lower energy intake in the TP and STP group was strongly related to the decrease in visceral fat weight. In study 2, after caecal fermentation suppression with antibiotics, STP treatment decreased the visceral fat mass. In study 3, the plasma glucose levels and incremental area under the curve (AUC) after ingestion of a STP-containing suspension were lower than those after ingestion of suspension alone. These findings suggest the reduction of carbohydrate absorption during the gastrointestinal passage after TP and STP treatment. Our data indicate that the reduced obesity development in rats fed a HF diet may be attributed to the low metabolisable energy density of carbohydrates in the spent turmeric, independent of SCFA-mediated factors. PMID:26583652

  8. Maternal high-fat diet programming of the neuroendocrine system and behavior.

    Science.gov (United States)

    Sullivan, Elinor L; Riper, Kellie M; Lockard, Rachel; Valleau, Jeanette C

    2015-11-01

    This article is part of a Special Issue "SBN 2014". Maternal obesity, metabolic state, and diet during gestation have profound effects on offspring development. The prevalence of neurodevelopmental and mental health disorders has risen rapidly in the last several decades in parallel with the rise in obesity rates. Evidence from epidemiological studies indicates that maternal obesity and metabolic complications increase the risk of offspring developing behavioral disorders such as attention deficit hyperactivity disorder (ADHD), autism spectrum disorders (ASD), and schizophrenia. Animal models show that a maternal diet high in fat similarly disrupts behavioral programming of offspring, with animals showing social impairments, increased anxiety and depressive behaviors, reduced cognitive development, and hyperactivity. Maternal obesity, metabolic conditions, and high fat diet consumption increase maternal leptin, insulin, glucose, triglycerides, and inflammatory cytokines. This leads to increased risk of placental dysfunction, and altered fetal neuroendocrine development. Changes in brain development that likely contribute to the increased risk of behavioral and mental health disorders include increased inflammation in the brain, as well as alterations in the serotonergic system, dopaminergic system and hypothalamic-pituitary-adrenal (HPA) axis. PMID:25913366

  9. Castration influences intestinal microflora and induces abdominal obesity in high-fat diet-fed mice.

    Science.gov (United States)

    Harada, Naoki; Hanaoka, Ryo; Horiuchi, Hiroko; Kitakaze, Tomoya; Mitani, Takakazu; Inui, Hiroshi; Yamaji, Ryoichi

    2016-01-01

    Late-onset hypogonadism (i.e. androgen deficiency) raises the risk for abdominal obesity in men. The mechanism for this obesity is unclear. Here, we demonstrated that hypogonadism after castration caused abdominal obesity in high-fat diet (HFD)-fed, but not in standard diet (SD)-fed, C57BL/6J mice. Furthermore, the phenotype was not induced in mice treated with antibiotics that disrupt the intestinal microflora. In HFD-fed mice, castration increased feed efficiency and decreased fecal weight per food intake. Castration also induced in an increase of visceral fat mass only in the absence of antibiotics in HFD-fed mice, whereas subcutaneous fat mass was increased by castration irrespective of antibiotics. Castration reduced the expression in the mesenteric fat of both adipose triglyceride lipase and hormone-sensitive lipase in HFD-fed mice, which was not observed in the presence of antibiotics. Castration decreased thigh muscle (i.e. quadriceps and hamstrings) mass, elevated fasting blood glucose levels, and increased liver triglyceride levels in a HFD-dependent manner, whereas these changes were not observed in castrated mice treated with antibiotics. The Firmicutes/Bacteroidetes ratio and Lactobacillus species increased in the feces of HFD-fed castrated mice. These results show that androgen (e.g. testosterone) deficiency can alter the intestinal microbiome and induce abdominal obesity in a diet-dependent manner. PMID:26961573

  10. Unaltered Prion Pathogenesis in a Mouse Model of High-Fat Diet-Induced Insulin Resistance.

    Directory of Open Access Journals (Sweden)

    Caihong Zhu

    Full Text Available Epidemiological, clinical, and experimental animal studies suggest a strong correlation between insulin resistance and Alzheimer's disease. In fact, type-2 diabetes is considered an important risk factor of developing Alzheimer's disease. In addition, impaired insulin signaling in the Alzheimer's disease brain may promote Aβ production, impair Aβ clearance and induce tau hyperphosphorylation, thereby leading to deterioration of the disease. The pathological prion protein, PrPSc, deposits in the form of extracellular aggregates and leads to dementia, raising the question as to whether prion pathogenesis may also be affected by insulin resistance. We therefore established high-fat diet-induced insulin resistance in tga20 mice, which overexpress the prion protein. We then inoculated the insulin-resistant mice with prions. We found that insulin resistance in tga20 mice did not affect prion disease progression, PrPSc deposition, astrogliosis or microglial activation, and had no effect on survival. Our study demonstrates that in a mouse model, insulin resistance does not significantly contribute to prion pathogenesis.

  11. Antiatherogenic Effect of Camellia japonica Fruit Extract in High Fat Diet-Fed Rats

    Directory of Open Access Journals (Sweden)

    Hyun-Ho Lee

    2016-01-01

    Full Text Available Hypercholesterolemia is a well-known etiological factor for cardiovascular disease and a common symptom of most types of metabolic disorders. Camellia japonica is a traditional garden plant, and its flower and seed have been used as a base oil of traditional cosmetics in East Asia. The present study was carried out to evaluate the effect of C. japonica fruit extracts (CJF in a high fat diet- (HFD- induced hypercholesterolemic rat model. CJF was administered orally at three different doses: 100, 400, and 800 mg·kg−1·day−1 (CJF 100, 400, and 800, resp.. Our results showed that CJF possessed strong cholesterol-lowering potency as indicated by the decrease in serum total cholesterol (TC, triglyceride (TG, and low-density lipoprotein (LDL, accompanied by an increase in serum high-density lipoprotein (HDL. Furthermore, CJF reduced serum lipid peroxidation by suppressing the formation of thiobarbituric acid reactive substance. In addition, oil red O (ORO staining of rat arteries showed decreased lipid-positive staining in the CJF-treated groups compared to the control HFD group. Taken together, these results suggest that CJF could be a potent herbal therapeutic option and source of a functional food for the prevention and treatment of atherosclerosis and other diseases associated with hypercholesterolemia.

  12. High-carbohydrate, high-fat diet-induced metabolic syndrome and cardiovascular remodeling in rats.

    Science.gov (United States)

    Panchal, Sunil K; Poudyal, Hemant; Iyer, Abishek; Nazer, Reeza; Alam, Md Ashraful; Diwan, Vishal; Kauter, Kathleen; Sernia, Conrad; Campbell, Fiona; Ward, Leigh; Gobe, Glenda; Fenning, Andrew; Brown, Lindsay

    2011-05-01

    The prevalence of metabolic syndrome including central obesity, insulin resistance, impaired glucose tolerance, hypertension, and dyslipidemia is increasing. Development of adequate therapy for metabolic syndrome requires an animal model that mimics the human disease state. Therefore, we have characterized the metabolic, cardiovascular, hepatic, renal, and pancreatic changes in male Wistar rats (8-9 weeks old) fed on a high-carbohydrate, high-fat diet including condensed milk (39.5%), beef tallow (20%), and fructose (17.5%) together with 25% fructose in drinking water; control rats were fed a cornstarch diet. During 16 weeks on this diet, rats showed progressive increases in body weight, energy intake, abdominal fat deposition, and abdominal circumference along with impaired glucose tolerance, dyslipidemia, hyperinsulinemia, and increased plasma leptin and malondialdehyde concentrations. Cardiovascular signs included increased systolic blood pressure and endothelial dysfunction together with inflammation, fibrosis, hypertrophy, increased stiffness, and delayed repolarization in the left ventricle of the heart. The liver showed increased wet weight, fat deposition, inflammation, and fibrosis with increased plasma activity of liver enzymes. The kidneys showed inflammation and fibrosis, whereas the pancreas showed increased islet size. In comparison with other models of diabetes and obesity, this diet-induced model more closely mimics the changes observed in human metabolic syndrome. PMID:21572266

  13. High-carbohydrate high-fat diet–induced metabolic syndrome and cardiovascular remodeling in rats.

    Science.gov (United States)

    Panchal, Sunil K; Poudyal, Hemant; Iyer, Abishek; Nazer, Reeza; Alam, Ashraful; Diwan, Vishal; Kauter, Kathleen; Sernia, Conrad; Campbell, Fiona; Ward, Leigh; Gobe, Glenda; Fenning, Andrew; Brown, Lindsay

    2011-01-01

    The prevalence of metabolic syndrome including central obesity, insulin resistance, impaired glucose tolerance, hypertension, and dyslipidemia is increasing. Development of adequate therapy for metabolic syndrome requires an animal model that mimics the human disease state. Therefore, we have characterized the metabolic, cardiovascular, hepatic, renal, and pancreatic changes in male Wistar rats (8-9 weeks old) fed on a high-carbohydrate, high-fat diet including condensed milk (39.5%), beef tallow (20%), and fructose (17.5%) together with 25% fructose in drinking water; control rats were fed a cornstarch diet. During 16 weeks on this diet, rats showed progressive increases in body weight, energy intake, abdominal fat deposition, and abdominal circumference along with impaired glucose tolerance, dyslipidemia, hyperinsulinemia, and increased plasma leptin and malondialdehyde concentrations. Cardiovascular signs included increased systolic blood pressure and endothelial dysfunction together with inflammation, fibrosis, hypertrophy, increased stiffness, and delayed repolarization in the left ventricle of the heart. The liver showed increased wet weight, fat deposition, inflammation, and fibrosis with increased plasma activity of liver enzymes. The kidneys showed inflammation and fibrosis, whereas the pancreas showed increased islet size. In comparison with other models of diabetes and obesity, this diet-induced model more closely mimics the changes observed in human metabolic syndrome. PMID:20966763

  14. High fat diet drives obesity regardless the composition of gut microbiota in mice.

    Science.gov (United States)

    Rabot, Sylvie; Membrez, Mathieu; Blancher, Florence; Berger, Bernard; Moine, Déborah; Krause, Lutz; Bibiloni, Rodrigo; Bruneau, Aurélia; Gérard, Philippe; Siddharth, Jay; Lauber, Christian L; Chou, Chieh Jason

    2016-01-01

    The gut microbiota is involved in many aspects of host physiology but its role in body weight and glucose metabolism remains unclear. Here we studied the compositional changes of gut microbiota in diet-induced obesity mice that were conventionally raised or received microbiota transplantation. In conventional mice, the diversity of the faecal microbiota was weakly associated with 1(st) week weight gain but transferring the microbiota of mice with contrasting weight gain to germfree mice did not change obesity development or feed efficiency of recipients regardless whether the microbiota was taken before or after 10 weeks high fat (HF) feeding. Interestingly, HF-induced glucose intolerance was influenced by microbiota inoculation and improved glucose tolerance was associated with a low Firmicutes to Bacteroidetes ratio. Transplantation of Bacteroidetes rich microbiota compared to a control microbiota ameliorated glucose intolerance caused by HF feeding. Altogether, our results demonstrate that gut microbiota is involved in the regulation of glucose metabolism and the abundance of Bacteroidetes significantly modulates HF-induced glucose intolerance but has limited impact on obesity in mice. Our results suggest that gut microbiota is a part of complex aetiology of insulin resistance syndrome, individual microbiota composition may cause phenotypic variation associated with HF feeding in mice. PMID:27577172

  15. Proinflammatory Cytokines in Prostate Cancer Development and Progression Promoted by High-Fat Diet

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    Hua Xu

    2015-01-01

    Full Text Available Background. We aimed to examine whether proinflammatory cytokines participated in prostate cancer (PCa development and progression promoted by high-fat diet (HFD. Methods. TRAMP (transgenic adenocarcinoma mouse prostate mice were randomly divided into two groups: normal diet group and HFD group. Mortality rate and tumor formation rate were examined. TRAMP mice were sacrificed and sampled on the 20th, 24th, and 28th week, respectively. Levels of proinflammatory cytokines, including IL-1α, IL-1β, IL-6, and TNF-α, were tested by FlowCytomix. Prostate tissue of TRAMP mice was used for histology study. Results. A total of 13 deaths of TRAMP mice were observed, among which 3 (8.33% were from the normal diet group and 10 (27.78% from the HFD group. The mortality rate of TRAMP mice from HFD group was significantly higher than that of normal diet group (P=0.032. Tumor formation rate at 20th week of age of HFD group was significantly higher than that of normal diet group (P=0.045. Proinflammatory cytokines levels, including IL-1α, IL-1β, IL-6, and TNF-α, were significantly higher in HFD TRAMP mice. Conclusions. HFD could promote TRAMP mouse PCa development and progression with elevated proinflammatory cytokines levels. Proinflammatory cytokines could contribute to PCa development and progression promoted by HFD.

  16. High-fat diets promote insulin resistance through cytokine gene expression in growing female rats.

    Science.gov (United States)

    Flanagan, Anne M; Brown, Jackie L; Santiago, Consuelo A; Aad, Pauline Y; Spicer, Leon J; Spicer, Maria T

    2008-08-01

    To determine if tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6). IL-6 gene expression is influenced by amount and source of dietary fat, 30 weanling female rats were randomly assigned to a moderate-fat soybean oil (MFS; 22% of total energy fed as fat), high-fat (HF) soybean oil (HFS; 39% of total energy fed as fat), or HF tallow (HFT; 39% of total energy fed as fat) diet treatments. Oral glucose tolerance tests (OGTT) were conducted serially over 10 weeks of treatment. HFT and HFS rats gained more weight and had greater body fat than the MFS rats fed similar amounts of energy. Both groups of HF-fed rats had greater (PHFT compared to HFS and MFS rats. There were positive correlations (PHFT group, after which, on Week 9, insulin secretion was diminished in response to the OGTT, suggesting impaired pancreatic insulin secretion. HFS rats exhibited insulin resistance on Week 9 OGTT. In summary, an HFT diet fed to growing female rats caused insulin resistance associated with increased hepatic TNF-alpha mRNA leading to pancreatic insufficiency. Early-onset insulin resistance related to the inflammatory process in obesity is influenced by the amount and type of fat in the diet. PMID:17904344

  17. High-Fat Diet Induced Anxiety and Anhedonia: Impact on Brain Homeostasis and Inflammation.

    Science.gov (United States)

    Dutheil, Sophie; Ota, Kristie T; Wohleb, Eric S; Rasmussen, Kurt; Duman, Ronald S

    2016-06-01

    Depression and type 2 diabetes (T2D) are highly comorbid disorders that carry a large public health burden. However, there is a clear lack of knowledge of the neural pathological pathways underlying these illnesses. The present study aims to elucidate the molecular mechanisms by which a diet rich in fat can cause multiple complications in the brain, thereby affecting intracellular signaling and gene expression that underlie anxiety and depressive behaviors. The results show that a high-fat diet (HFD; ~16 weeks) causes anxiety and anhedonic behaviors. Importantly, the results also show that 4 months of HFD causes disruption of intracellular cascades involved in synaptic plasticity and insulin signaling/glucose homeostasis (ie, Akt, extracellular signal-regulated kinase (ERK), P70S6K), as well as increased corticosterone levels and activation of the innate immune system, including elevation of inflammatory cytokines (ie, IL-6, IL-1β, TNFα). Interestingly, the rapid acting antidepressant ketamine reverses the behavioral deficits caused by HFD and activates ERK and P70S6 kinase signaling in the prefrontal cortex. In addition, we found that pharmacological blockade of the innate immune inflammasome system by repeated administration of an inhibitor of the purinergic P2X7 receptor blocks the anxiety caused by HFD. Together these studies further elucidate the signaling pathways that underlie chronic HFD exposure on anxiety and depressive behaviors, and identify novel therapeutic targets for patients with metabolic disorder or T2D who suffer from anxiety and depression. PMID:26658303

  18. Effect of high-fat diets on mood and learning performance in adolescent mice.

    Science.gov (United States)

    Del Rio, Danila; Morales, Lidia; Ruiz-Gayo, Mariano; Del Olmo, Nuria

    2016-09-15

    Recent studies point to dietary factors as important effectors in the brain and epidemiological studies suggest a direct relationship between mood and anxiety disorders, cognitive impairment and obesity. Nevertheless the link between the consumption of high-fat diets (HFD) and emotional disorders still remains unclear. This issue is of particular interest during adolescence, which is an important period for shaping learning and memory acquisition that can be particularly sensitive to the detrimental effects of HFD. Otherwise, major depressive disorder and anxiety crisis often emerge in adolescence. In the current study we have characterized in adolescent mice i) the onset of HFD-induced memory impairment using the novel location recognition (NLR) paradigm, and ii) the effect of HFD on depression- and anxiety-related behaviors by using the forced swimming and the elevated plus maze tests, respectively. Here we report that memory impairments induced by HFD were already perceptible after 4-weeks HFD whereas HFD induced already antidepressant-like effects after 48-h, that remained after long-term treatment (8 weeks). No effects in anxiety were found. These data indicate that the antidepressant-like effect of HFD is independent of memory deficits as it was already present after 48-h HFD, while no effects in memory were still observed at this time. PMID:27212119

  19. High Fat Diet Induces Adhesion of Platelets to Endothelium in Two Models of Dyslipidemia

    Science.gov (United States)

    Gonzalez, Jaime; Donoso, Wendy; Díaz, Natalia; Albornoz, María Eliana; Huilcaman, Ricardo; Morales, Erik

    2014-01-01

    Cardiovascular diseases (CVD) represent about 30% of all global deaths. It is currently accepted that, in the atherogenic process, platelets play an important role, contributing to endothelial activation and modulation of the inflammatory phenomenon, promoting the beginning and formation of lesions and their subsequent thrombotic complications. The objective of the present work was to study using immunohistochemistry, the presence of platelets, monocytes/macrophages, and cell adhesion molecules (CD61, CD163, and CD54), in two stages of the atheromatous process. CF-1 mice fed a fat diet were used to obtain early stages of atheromatous process, denominated early stage of atherosclerosis, and ApoE−/− mice fed a fat diet were used to observe advanced stages of atherosclerosis. The CF-1 mice model presented immunostaining on endothelial surface for all three markers studied; the advanced atherosclerosis model in ApoE−/− mice also presented granular immunostaining on lesion thickness, for the same markers. These results suggest that platelets participate in atheromatous process from early stages to advance d stages. High fat diet induces adhesion of platelets to endothelial cells in vivo. These findings support studying the participation of platelets in the formation of atheromatous plate. PMID:25328689

  20. Effects of high fat diets on rodent liver bioenergetics and oxidative imbalance.

    Science.gov (United States)

    Kakimoto, Pâmela A; Kowaltowski, Alicia J

    2016-08-01

    Human metabolic diseases can be mimicked in rodents by using dietary interventions such as high fat diets (HFD). Nonalcoholic fatty liver disease (NAFLD) develops as a result of HFD and the disease may progress in a manner involving increased production of oxidants. The main intracellular source of these oxidants are mitochondria, which are also responsible for lipid metabolism and thus widely recognized as important players in the pathology and progression of steatosis. Here, we review publications that study redox and bioenergetic effects of HFD in the liver. We find that dietary composition and protocol implementations vary widely, as do the results of these dietary interventions. Overall, all HFD promote steatosis, changes in β-oxidation, generation and consequences of oxidants, while effects on body weight, insulin signaling and other bioenergetic parameters are more variable with the experimental models adopted. Our review provides a broad analysis of the bioenergetic and redox changes promoted by HFD as well as suggestions for changes and specifications in methodologies that may help explain apparent disparities in the current literature. PMID:26826574

  1. Lipidomic Analysis of Serum from High Fat Diet Induced Obese Mice

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    Kristina Eisinger

    2014-02-01

    Full Text Available Lipid metabolites regulate fatty acid and glucose homeostasis. The intention of the current study is to identify circulating lipid species, which are altered in rodent obesity and strongly correlate with the classically measured metabolites glucose, triglycerides, and cholesterol. Mice fed a high fat diet (HFD for 14 weeks have increased body weight and fasting glucose. Serum triglycerides are not altered, while cholesterol tends to be increased. Accordingly, major cholesteryl ester (CE species and free cholesterol are not significantly raised in obesity while minor metabolites, including CE 20:3 and CE 18:3, are increased or reduced, respectively. Distinct sphingomyelin (SM species are elevated while ceramides are not raised. Phosphatidylinositol (PI species, including PI 34:1, are raised while others are decreased. PI 34:1 strongly correlates with fasting glucose and proinsulin levels. Phosphatidylcholine (PC 26:0, 40:2, and 40:5, which are induced in obesity, correlate with cholesterol. PC 38:4 and PC 40:6 are also raised in fat fed mice and positively correlate with fasting glucose. Lysophosphatidylcholine (LPC species are also changed in obesity and the already shown reduction of LPC 16:1 has been confirmed. LPC 22:4, which is increased, correlates with serum cholesterol. The data indicate that circulating levels of various lipid species are changed in the obesity model studied and some of them are strongly associated with classically measured metabolites.

  2. Sesamin Ameliorates High-Fat Diet–Induced Dyslipidemia and Kidney Injury by Reducing Oxidative Stress

    Science.gov (United States)

    Zhang, Ruijuan; Yu, Yan; Deng, Jianjun; Zhang, Chao; Zhang, Jinghua; Cheng, Yue; Luo, Xiaoqin; Han, Bei; Yang, Haixia

    2016-01-01

    The study explored the protective effect of sesamin against lipid-induced renal injury and hyperlipidemia in a rat model. An animal model of hyperlipidemia was established in Sprague-Dawley rats. Fifty-five adult Sprague-Dawley rats were divided into five groups. The control group was fed a standard diet, while the other four groups were fed a high-fat diet for 5 weeks to induce hyperlipidemia. Three groups received oral sesamin in doses of 40, 80, or 160 mg/(kg·day). Seven weeks later, the blood lipids, renal function, antioxidant enzyme activities, and hyperoxide levels in kidney tissues were measured. The renal pathological changes and expression levels of collagen type IV (Col-IV) and α-smooth muscle actin (α-SMA) were analyzed. The administration of sesamin improved the serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, apolipoprotein-B, oxidized-low-density lipoprotein, and serum creatinine levels in hyperlipidemic rats, while it increased the high-density lipoprotein cholesterol and apolipoprotein-A levels. Sesamin reduced the excretion of 24-h urinary protein and urinary albumin and downregulated α-SMA and Col-IV expression. Moreover, sesamin ameliorated the superoxide dismutase activity and reduced malondialdehyde levels in kidney tissue. Sesamin could mediate lipid metabolism and ameliorate renal injury caused by lipid metabolism disorders in a rat model of hyperlipidemia. PMID:27171111

  3. Sesamin Ameliorates High-Fat Diet–Induced Dyslipidemia and Kidney Injury by Reducing Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Ruijuan Zhang

    2016-05-01

    Full Text Available The study explored the protective effect of sesamin against lipid-induced renal injury and hyperlipidemia in a rat model. An animal model of hyperlipidemia was established in Sprague-Dawley rats. Fifty-five adult Sprague-Dawley rats were divided into five groups. The control group was fed a standard diet, while the other four groups were fed a high-fat diet for 5 weeks to induce hyperlipidemia. Three groups received oral sesamin in doses of 40, 80, or 160 mg/(kg·day. Seven weeks later, the blood lipids, renal function, antioxidant enzyme activities, and hyperoxide levels in kidney tissues were measured. The renal pathological changes and expression levels of collagen type IV (Col-IV and α-smooth muscle actin (α-SMA were analyzed. The administration of sesamin improved the serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, apolipoprotein-B, oxidized-low-density lipoprotein, and serum creatinine levels in hyperlipidemic rats, while it increased the high-density lipoprotein cholesterol and apolipoprotein-A levels. Sesamin reduced the excretion of 24-h urinary protein and urinary albumin and downregulated α-SMA and Col-IV expression. Moreover, sesamin ameliorated the superoxide dismutase activity and reduced malondialdehyde levels in kidney tissue. Sesamin could mediate lipid metabolism and ameliorate renal injury caused by lipid metabolism disorders in a rat model of hyperlipidemia.

  4. Sesamin Ameliorates High-Fat Diet-Induced Dyslipidemia and Kidney Injury by Reducing Oxidative Stress.

    Science.gov (United States)

    Zhang, Ruijuan; Yu, Yan; Deng, Jianjun; Zhang, Chao; Zhang, Jinghua; Cheng, Yue; Luo, Xiaoqin; Han, Bei; Yang, Haixia

    2016-01-01

    The study explored the protective effect of sesamin against lipid-induced renal injury and hyperlipidemia in a rat model. An animal model of hyperlipidemia was established in Sprague-Dawley rats. Fifty-five adult Sprague-Dawley rats were divided into five groups. The control group was fed a standard diet, while the other four groups were fed a high-fat diet for 5 weeks to induce hyperlipidemia. Three groups received oral sesamin in doses of 40, 80, or 160 mg/(kg·day). Seven weeks later, the blood lipids, renal function, antioxidant enzyme activities, and hyperoxide levels in kidney tissues were measured. The renal pathological changes and expression levels of collagen type IV (Col-IV) and α-smooth muscle actin (α-SMA) were analyzed. The administration of sesamin improved the serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, apolipoprotein-B, oxidized-low-density lipoprotein, and serum creatinine levels in hyperlipidemic rats, while it increased the high-density lipoprotein cholesterol and apolipoprotein-A levels. Sesamin reduced the excretion of 24-h urinary protein and urinary albumin and downregulated α-SMA and Col-IV expression. Moreover, sesamin ameliorated the superoxide dismutase activity and reduced malondialdehyde levels in kidney tissue. Sesamin could mediate lipid metabolism and ameliorate renal injury caused by lipid metabolism disorders in a rat model of hyperlipidemia. PMID:27171111

  5. Protective effect of lycopene on high-fat diet-induced cognitive impairment in rats.

    Science.gov (United States)

    Wang, Zhiqiang; Fan, Jin; Wang, Jian; Li, Yuxia; Xiao, Li; Duan, Dan; Wang, Qingsong

    2016-08-01

    A Western diet, high in saturated fats, has been linked to the development of cognitive impairment. Lycopene has recently received considerable attention for its potent protective properties demonstrated in several models of nervous system dysfunction. However, it remains unclear whether lycopene exerts protective effects on cognition. The present study aimed to investigate the protective effects of lycopene on learning and memory impairment and the potential underlying mechanism in rats fed a high-fat diet (HFD). One-month-old male rats were fed different diets for 16 weeks (n=12 per group), including a standard chow diet (CD), a HFD, or a HFD plus lycopene (4mg/kg, oral gavage in the last three weeks). Behavioral testing, including the Morris water maze (MWM), object recognition task (ORT), and anxiety-like behavior in an open field (OF), were assessed at week 16. The dendritic spine density and neuronal density in the hippocampal CA1 subfield were subsequently measured. The results indicate that HFD consumption for 16 weeks significantly impaired spatial memory (Pobject recognition memory (Plearning and memory impairments and prevented the reduction in dendritic spine density (P<0.001). Thus, this study indicated that lycopene helps to protect HFD induced cognitive dysfunction. PMID:27177726

  6. Bardoxolone Methyl Prevents High-Fat Diet-Induced Colon Inflammation in Mice.

    Science.gov (United States)

    Dinh, Chi H L; Yu, Yinghua; Szabo, Alexander; Zhang, Qingsheng; Zhang, Peng; Huang, Xu-Feng

    2016-04-01

    Obesity induces chronic, low-grade inflammation, which increases the risk of colon cancer. We investigated the preventive effects of Bardoxolone methyl (BARD) on high-fat diet (HFD)-induced inflammation in a mouse colon. Male C57BL/6J mice (n=7) were fed a HFD (HFD group), HFD plus BARD (10 mg/kg) in drinking water (HFD/BARD group), or normal laboratory chow diet (LFD group) for 21 weeks. In HFD mice, BARD reduced colon thickness and decreased colon weight per length. This was associated with an increase in colon crypt depth and the number of goblet cells per crypt. BARD reduced the expression of F4/80 and CD11c but increased CD206 and IL-10, indicating an anti-inflammatory effect. BARD prevented an increase of the intracellular pro-inflammatory biomarkers (NF-қB, p NF-қB, IL-6, TNF-α) and cell proliferation markers (Cox2 and Ki67). BARD prevented fat deposition in the colon wall and prevented microbial population changes. Overall, we report the preventive effects of BARD on colon inflammation in HFD-fed mice through its regulation of macrophages, NF-қB, cytokines, Cox2 and Ki67, fat deposition and microflora. PMID:26920068

  7. Modulation of PPAR Expression and Activity in Response to Polyphenolic Compounds in High Fat Diets

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    J. Abraham Domínguez-Avila

    2016-06-01

    Full Text Available Peroxisome proliferator-activated receptors (PPAR are transcription factors that modulate energy metabolism in liver, adipose tissue and muscle. High fat diets (HFD can negatively impact PPAR expression or activity, favoring obesity, dyslipidemia, insulin resistance and other conditions. However, polyphenols (PP found in vegetable foodstuffs are capable of positively modulating this pathway. We therefore focused this review on the possible effects that PP can have on PPAR when administered together with HFD. We found that PP from diverse sources, such as coffee, olives, rice, berries and others, are capable of inducing the expression of genes involved in a decrease of adipose mass, liver and serum lipids and lipid biosynthesis in animal and cell models of HFD. Since cells or gut bacteria can transform PP into different metabolites, it is possible that a synergistic or antagonistic effect ultimately occurs. PP molecules from vegetable sources are an interesting option to maintain or return to a state of energy homeostasis, possibly due to an adequate PPAR expression and activity.

  8. Modulation of PPAR Expression and Activity in Response to Polyphenolic Compounds in High Fat Diets.

    Science.gov (United States)

    Domínguez-Avila, J Abraham; González-Aguilar, Gustavo A; Alvarez-Parrilla, Emilio; de la Rosa, Laura A

    2016-01-01

    Peroxisome proliferator-activated receptors (PPAR) are transcription factors that modulate energy metabolism in liver, adipose tissue and muscle. High fat diets (HFD) can negatively impact PPAR expression or activity, favoring obesity, dyslipidemia, insulin resistance and other conditions. However, polyphenols (PP) found in vegetable foodstuffs are capable of positively modulating this pathway. We therefore focused this review on the possible effects that PP can have on PPAR when administered together with HFD. We found that PP from diverse sources, such as coffee, olives, rice, berries and others, are capable of inducing the expression of genes involved in a decrease of adipose mass, liver and serum lipids and lipid biosynthesis in animal and cell models of HFD. Since cells or gut bacteria can transform PP into different metabolites, it is possible that a synergistic or antagonistic effect ultimately occurs. PP molecules from vegetable sources are an interesting option to maintain or return to a state of energy homeostasis, possibly due to an adequate PPAR expression and activity. PMID:27367676

  9. Antiatherogenic Effect of Camellia japonica Fruit Extract in High Fat Diet-Fed Rats.

    Science.gov (United States)

    Lee, Hyun-Ho; Paudel, Keshav Raj; Jeong, Jieun; Wi, An-Jin; Park, Whoa-Shig; Kim, Dong-Wook; Oak, Min-Ho

    2016-01-01

    Hypercholesterolemia is a well-known etiological factor for cardiovascular disease and a common symptom of most types of metabolic disorders. Camellia japonica is a traditional garden plant, and its flower and seed have been used as a base oil of traditional cosmetics in East Asia. The present study was carried out to evaluate the effect of C. japonica fruit extracts (CJF) in a high fat diet- (HFD-) induced hypercholesterolemic rat model. CJF was administered orally at three different doses: 100, 400, and 800 mg·kg(-1)·day(-1) (CJF 100, 400, and 800, resp.). Our results showed that CJF possessed strong cholesterol-lowering potency as indicated by the decrease in serum total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL), accompanied by an increase in serum high-density lipoprotein (HDL). Furthermore, CJF reduced serum lipid peroxidation by suppressing the formation of thiobarbituric acid reactive substance. In addition, oil red O (ORO) staining of rat arteries showed decreased lipid-positive staining in the CJF-treated groups compared to the control HFD group. Taken together, these results suggest that CJF could be a potent herbal therapeutic option and source of a functional food for the prevention and treatment of atherosclerosis and other diseases associated with hypercholesterolemia. PMID:27340422

  10. High fat diet drives obesity regardless the composition of gut microbiota in mice

    Science.gov (United States)

    Rabot, Sylvie; Membrez, Mathieu; Blancher, Florence; Berger, Bernard; Moine, Déborah; Krause, Lutz; Bibiloni, Rodrigo; Bruneau, Aurélia; Gérard, Philippe; Siddharth, Jay; Lauber, Christian L.; Chou, Chieh Jason

    2016-01-01

    The gut microbiota is involved in many aspects of host physiology but its role in body weight and glucose metabolism remains unclear. Here we studied the compositional changes of gut microbiota in diet-induced obesity mice that were conventionally raised or received microbiota transplantation. In conventional mice, the diversity of the faecal microbiota was weakly associated with 1st week weight gain but transferring the microbiota of mice with contrasting weight gain to germfree mice did not change obesity development or feed efficiency of recipients regardless whether the microbiota was taken before or after 10 weeks high fat (HF) feeding. Interestingly, HF-induced glucose intolerance was influenced by microbiota inoculation and improved glucose tolerance was associated with a low Firmicutes to Bacteroidetes ratio. Transplantation of Bacteroidetes rich microbiota compared to a control microbiota ameliorated glucose intolerance caused by HF feeding. Altogether, our results demonstrate that gut microbiota is involved in the regulation of glucose metabolism and the abundance of Bacteroidetes significantly modulates HF-induced glucose intolerance but has limited impact on obesity in mice. Our results suggest that gut microbiota is a part of complex aetiology of insulin resistance syndrome, individual microbiota composition may cause phenotypic variation associated with HF feeding in mice. PMID:27577172

  11. Maternal High Fat Diet Affects Offspring’s Vitamin K-Dependent Proteins Expression Levels

    Science.gov (United States)

    Lanham, Stuart; Cagampang, Felino R.; Oreffo, Richard O. C.

    2015-01-01

    Studies suggest bone growth & development and susceptibility to vascular disease in later life are influenced by maternal nutrition, during intrauterine and early postnatal life. There is evidence for a role of vitamin K-dependent proteins (VKDPs) including Osteocalcin, Matrix-gla protein, Periostin, and Gas6, in bone and vascular development. This study extends the analysis of VKDPs previously conducted in 6 week old offspring, into offspring of 30 weeks of age, to assess the longer term effects of a maternal and postnatal high fat (HF) diet on VKDP expression. Overall a HF maternal diet and offspring diet exacerbated the bone changes observed. Sex specific and tissue specific differences were observed in VKDP expression for both aorta and femoral tissues. In addition, significant correlations were observed between femoral OCN, Periostin Gas6, and Vkor expression levels and measures of femoral bone structure. Furthermore, MGP, OCN, Ggcx and Vkor expression levels correlated to mass and fat volume, in both sexes. In summary the current study has highlighted the importance of the long-term effects of maternal nutrition on offspring bone development and the correlation of VKDPs to bone structure. PMID:26381752

  12. Maternal High Fat Diet Affects Offspring's Vitamin K-Dependent Proteins Expression Levels.

    Directory of Open Access Journals (Sweden)

    Stuart Lanham

    Full Text Available Studies suggest bone growth & development and susceptibility to vascular disease in later life are influenced by maternal nutrition, during intrauterine and early postnatal life. There is evidence for a role of vitamin K-dependent proteins (VKDPs including Osteocalcin, Matrix-gla protein, Periostin, and Gas6, in bone and vascular development. This study extends the analysis of VKDPs previously conducted in 6 week old offspring, into offspring of 30 weeks of age, to assess the longer term effects of a maternal and postnatal high fat (HF diet on VKDP expression. Overall a HF maternal diet and offspring diet exacerbated the bone changes observed. Sex specific and tissue specific differences were observed in VKDP expression for both aorta and femoral tissues. In addition, significant correlations were observed between femoral OCN, Periostin Gas6, and Vkor expression levels and measures of femoral bone structure. Furthermore, MGP, OCN, Ggcx and Vkor expression levels correlated to mass and fat volume, in both sexes. In summary the current study has highlighted the importance of the long-term effects of maternal nutrition on offspring bone development and the correlation of VKDPs to bone structure.

  13. Modulation of PPAR Expression and Activity in Response to Polyphenolic Compounds in High Fat Diets

    Science.gov (United States)

    Domínguez-Avila, J. Abraham; González-Aguilar, Gustavo A.; Alvarez-Parrilla, Emilio; de la Rosa, Laura A.

    2016-01-01

    Peroxisome proliferator-activated receptors (PPAR) are transcription factors that modulate energy metabolism in liver, adipose tissue and muscle. High fat diets (HFD) can negatively impact PPAR expression or activity, favoring obesity, dyslipidemia, insulin resistance and other conditions. However, polyphenols (PP) found in vegetable foodstuffs are capable of positively modulating this pathway. We therefore focused this review on the possible effects that PP can have on PPAR when administered together with HFD. We found that PP from diverse sources, such as coffee, olives, rice, berries and others, are capable of inducing the expression of genes involved in a decrease of adipose mass, liver and serum lipids and lipid biosynthesis in animal and cell models of HFD. Since cells or gut bacteria can transform PP into different metabolites, it is possible that a synergistic or antagonistic effect ultimately occurs. PP molecules from vegetable sources are an interesting option to maintain or return to a state of energy homeostasis, possibly due to an adequate PPAR expression and activity. PMID:27367676

  14. High-efficiency sample preparation approach to determine acrylamide levels in high-fat foods.

    Science.gov (United States)

    Li, Xiaodan; Li, Jinwei; Cao, Peirang; Liu, Yuanfa

    2016-08-01

    An improved sample preparation method was developed to enhance acrylamide recovery in high-fat foods. Prior to concentration, distilled deionized water was added to protect acrylamide from degradation, resulting in a higher acrylamide recovery rate from fried potato chips. A Chrome-Matrix C18 column (2.6 μm, 2.1 × 100 mm) was used for the first time to analyze acrylamide levels using ultra high performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry, displaying good separation of acrylamide from interference. A solid-phase extraction procedure was avoided, and an average recovery of >89.00% was achieved from different food matrices for three different acrylamide spiking levels. Good reproducibility was observed, with an intraday relative standard deviation of 0.04-2.38%, and an interday relative standard deviation of 2.34-3.26%. Thus, combining the improved sample preparation method for acrylamide analysis with the separation on a Chrome-Matrix C18 column (2.6 μm, 2.1 × 100 mm) using ultra high performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry is highly useful for analyzing acrylamide levels in complex food matrices. PMID:27279364

  15. Effects of Silybum marianum Extract on High-Fat Diet Induced Metabolic Disorders in Rats

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    Sayin Fatma Kubra

    2016-03-01

    Full Text Available Silybum marianum extract (SME has been used for centuries as a natural remedy for diseases of liver and biliary tract. Lately, it has been promoted as a nutritional supplement for beneficial effects on some risk factors of diabetes and hyperlipidemia. In this study we aimed to determine the effects of SME on high-fat diet (HFD induced metabolic disorders. Male Sprague Dawley rats were fed HFD for 11 weeks to induce obesity. SME was given to animals for two different durations, for 11 weeks or for 7 weeks. The results showed significant increase in plasma transaminases, total cholesterol (TC, triglycerides (TG, low density lipoprotein cholesterol (LDL-C, leptin, high sensitive C-reactive protein (hsCRP, glucose and insulin along with significant increase in body mass index (BMI and liver weights in rats fed the HFD diet compared to rats fed with standard rat diet. SME supplementation for different durations raised improvement in the HFD-induced metabolic disorders such as insulin resistance, hyperlipidemia and hepatopathy at different degrees. Our study concludes that SME can be well considered as an effective supplement to improve insulin and leptin sensitivity and hyperlipidemia and to suppress body weight gain.

  16. Extract of Sesbania grandiflora Ameliorates Hyperglycemia in High Fat Diet-Streptozotocin Induced Experimental Diabetes Mellitus.

    Science.gov (United States)

    Panigrahi, Ghanshyam; Panda, Chhayakanta; Patra, Arjun

    2016-01-01

    Background. Sesbania grandiflora has been traditionally used as antidiabetic, antioxidant, antipyretic, and expectorant and in the management of various ailments. Materials and Methods. The study evaluates the antidiabetic activity of methanolic extract of Sesbania grandiflora (MESG) in type 2 diabetic rats induced by low dose streptozotocine and high fat diet. Diabetic rats were given vehicle, MESG (200 and 400 mg/kg, p.o.), and the standard drug, metformin (10 mg/kg), for 28 days. During the experimental period, body weight, abdominal girth, food intake, fasting serum glucose, urine analyses were measured. Insulin tolerance test was carried out on 25th day of drug treatment period. Serum analyses for lipid profile and SGOT and SGPT and serums creatinine, urea, protein, SOD, and MDA were also carried out. At the end of the experiment, animals were euthanized, the liver and pancreas were immediately dissected out, and the ratio of pancreas to body weight and hepatic glycogen were calculated. Results. MESG (200 and 400 mg/kg, p.o.) induced significant reduction (P rats and also restored other parameters to normal level. Conclusion. Therefore, it is concluded that MESG has potential antihyperglycemic and antihyperlipemic activities and alleviate insulin resistance conditions. PMID:27313954

  17. Early responses of insulin signaling to high-carbohydrate and high-fat overfeeding

    Directory of Open Access Journals (Sweden)

    Gray Karen

    2009-09-01

    Full Text Available Abstract Background Early molecular changes of nutritionally-induced insulin resistance are still enigmatic. It is also unclear if acute overnutrition alone can alter insulin signaling in humans or if the macronutrient composition of the diet can modulate such effects. Methods To investigate the molecular correlates of metabolic adaptation to either high-carbohydrate (HC or high-fat (HF overfeeding, we conducted overfeeding studies in 21 healthy lean (BMI in vivo insulin sensitivity was assessed using the hyperinsulinemic-euglycemic clamp technique. Ex vivo insulin action was measured from skeletal muscle tissue samples obtained 15 minutes after insulin infusion was initiated. Results Overall there was no change in whole-body insulin sensitivity as measured by glucose disposal rate (GDR, EC: 12.1 ± 4.7; HC: 10.9 ± 2.7; HF: 10.8 ± 3.4. Assessment of skeletal muscle insulin signaling demonstrated increased tyrosine phosphorylation of IRS-1 (p Conclusion We conclude that acute bouts of overnutrition lead to changes at the cellular level before whole-body insulin sensitivity is altered. On a signaling level, HC overfeeding resulted in changes compatible with increased insulin sensitivity. In contrast, molecular changes in HF overfeeding were compatible with a reduced insulin sensitivity.

  18. Antiatherogenic Effect of Camellia japonica Fruit Extract in High Fat Diet-Fed Rats

    Science.gov (United States)

    Lee, Hyun-Ho; Paudel, Keshav Raj; Jeong, Jieun; Wi, An-Jin; Park, Whoa-Shig; Kim, Dong-Wook

    2016-01-01

    Hypercholesterolemia is a well-known etiological factor for cardiovascular disease and a common symptom of most types of metabolic disorders. Camellia japonica is a traditional garden plant, and its flower and seed have been used as a base oil of traditional cosmetics in East Asia. The present study was carried out to evaluate the effect of C. japonica fruit extracts (CJF) in a high fat diet- (HFD-) induced hypercholesterolemic rat model. CJF was administered orally at three different doses: 100, 400, and 800 mg·kg−1·day−1 (CJF 100, 400, and 800, resp.). Our results showed that CJF possessed strong cholesterol-lowering potency as indicated by the decrease in serum total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL), accompanied by an increase in serum high-density lipoprotein (HDL). Furthermore, CJF reduced serum lipid peroxidation by suppressing the formation of thiobarbituric acid reactive substance. In addition, oil red O (ORO) staining of rat arteries showed decreased lipid-positive staining in the CJF-treated groups compared to the control HFD group. Taken together, these results suggest that CJF could be a potent herbal therapeutic option and source of a functional food for the prevention and treatment of atherosclerosis and other diseases associated with hypercholesterolemia. PMID:27340422

  19. Balsamic Vinegar Improves High Fat-Induced Beta Cell Dysfunction via Beta Cell ABCA1

    Directory of Open Access Journals (Sweden)

    Hannah Seok

    2012-08-01

    Full Text Available BackgroundThe aim of this study was to investigate the effects of balsamic vinegar on β-cell dysfunction.MethodsIn this study, 28-week-old Otsuka Long-Evans Tokushima Fatty (OLETF rats were fed a normal chow diet or a high-fat diet (HFD and were provided with tap water or dilute balsamic vinegar for 4 weeks. Oral glucose tolerance tests and histopathological analyses were performed thereafter.ResultsIn rats fed both the both chow diet and the HFD, the rats given balsamic vinegar showed increased insulin staining in islets compared with tap water administered rats. Balsamic vinegar administration also increased β-cell ATP-binding cassette transporter subfamily A member 1 (ABCA1 expression in islets and decreased cholesterol levels.ConclusionThese findings provide the first evidence for an anti-diabetic effect of balsamic vinegar through improvement of β-cell function via increasing β-cell ABCA1 expression.

  20. CMKLR1 deficiency influences glucose tolerance and thermogenesis in mice on high fat diet.

    Science.gov (United States)

    Huang, Chen; Wang, Miaomiao; Ren, Lirong; Xiang, Liang; Chen, Jie; Li, Mengxia; Xiao, Tianxia; Ren, Peigen; Xiong, Likuan; Zhang, Jian V

    2016-04-29

    Obesity has become a global epidemic disease, contributing to increases in the prevalence of type 2 diabetes. CMKLR1, one of the receptors for chemerin, has a wide range of functions in physiological and pathological activity, including innate and adaptive immunity, inflammation, metabolism and reproduction. In our study, CMKLR1 deficiency did not influence the gain of body weight but did exacerbate glucose intolerance, increase serum insulin level, and promote insulin resistance in mice on high fat diets. The expression of thermogenesis related genes was examined and indicated to decrease in CMKLR1 knockout (KO) mice in both normal and cold environments, which indicated CMKLR1 influence the thermogenesis process. Cold exposure induced significant body mass decrease and improved glucose tolerance and insulin resistance in wild type HFD mice but had no obvious effect on CMKLR1 KO HFD mice. In vitro, loss of CMKLR1 did not significantly influence the differentiation of stromal vascular fibroblasts (SVFs) derived from adipose tissue, but did suppress the expression of thermogenesis related genes. Collectively, these data demonstrate that CMKLR1 deficiency induces inbalance of glucose metabolism and impairs the cold induced-thermogenesis process in high diet models. PMID:26972253

  1. Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: A study to assess the drug's cardiac ion channel profile ☆

    OpenAIRE

    Koenig, Xaver; Kovar, Michael; Rubi, Lena; Mike, Agnes K.; Lukacs, Peter; Gawali, Vaibhavkumar S; Todt, Hannes; Hilber, Karlheinz; Sandtner, Walter

    2013-01-01

    The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licenced as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channe...

  2. Ginsenoside Rb1 selectively inhibits the activity of L-type voltage-gated calcium channels in cultured rat hippocampal neurons

    Institute of Scientific and Technical Information of China (English)

    Zhi-ying LIN; Li-min CHEN; Jing ZHANG; Xiao-dong PAN; Yuan-gui ZHU; Qin-yong YE; Hua-pin HUANG; Xiao-chun CHEN

    2012-01-01

    Aim:To investigate the effect of ginsenoside Rb1 on voltage-gated calcium currents in cultured rat hippocampal neurons and the modulatory mechanism.Methods:Cultured hippocampal neurons were prepared from Sprague Dawley rat embryos.Whole-cell configuration of the patchclamp technique was used to record the voltage-gated calcium currents (VGCCs)from the hippocampal neurons,and the effect of Rb1 was examined.Results:Rb1 (2-100 μmol/L)inhibited VGCCs in a concentration-dependent manner,and the current was mostly recovered upon wash-out.The specific L-type Ca2+ channel inhibitor nifedipine (10 μmol/L)occluded Rb1-induced inhibition on VGCCs.Neither the selective N-type Ca2+ channel blocker ω-conotoxin-GVlA (1 μmoVL),nor the selective P/Q-type Ca2+ channel blocker ωo-agatoxin IVA (30 nmol/L)diminished Rb1-sensitive VGCCs.Rb1 induced a leftward shift of the steady-state inactivation curve of Ica to a negative potential without affecting its activation kinetics or reversal potential in the I-V curve.The inhibitory effect of Rb1 was neither abolished by the adenylyl cyclase activator forskolin (10 μmol/L),nor by the PKA inhibitor H-89 (10 μmol/L).Conclusion:Ginsenoside Rb1 selectively inhibits the activity of L-type voltage-gated calcium channels,without affecting the N-type or P/Q-type Ca2+ channels in hippocampal neurons,cAMP-PKA signaling pathway is not involved in this effect.

  3. Effects of chronic exercise on the endocannabinoid system in Wistar rats with high-fat diet-induced obesity.

    Science.gov (United States)

    Gamelin, François-Xavier; Aucouturier, Julien; Iannotti, Fabio Arturo; Piscitelli, Fabiana; Mazzarella, Enrico; Aveta, Teresa; Leriche, Melissa; Dupont, Erwan; Cieniewski-Bernard, Caroline; Montel, Valérie; Bastide, Bruno; Di Marzo, Vincenzo; Heyman, Elsa

    2016-06-01

    The endocannabinoid system is dysregulated during obesity in tissues involved in the control of food intake and energy metabolism. We examined the effect of chronic exercise on the tissue levels of endocannabinoids (eCBs) and on the expression of genes coding for cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2) (Cnr1 and Cnr2, respectively) in the subcutaneous (SAT) and visceral adipose tissues and in the soleus and extensor digitorim longus (EDL) muscles, in rats fed with standard or high-fat diet. Twenty-eight male Wistar rats were placed on high-fat diet or standard diet (HFD and Ctl groups, respectively) during 12 weeks whereafter half of each group was submitted to an exercise training period of 12 weeks (HFD + training and Ctl + training). Tissue levels of eCBs were measured by LC-MS while expressions of genes coding for CB1 and CB2 receptors were investigated by qPCR. High-fat diet induced an increase in anandamide (AEA) levels in soleus and EDL (p < 0.02). In soleus of the HFD group, these changes were accompanied by elevated Cnr1 messenger RNA (mRNA) levels (p < 0.05). In EDL, exercise training allowed to reduce significantly this diet-induced AEA increase (p < 0.005). 2-Arachidonoylglycerol (2-AG) levels were decreased and increased by high-fat diet in SAT and EDL, respectively (p < 0.04), but not affected by exercise training. Unlike the HFD + training group, 2-AG levels in soleus were also decreased in the HFD group compared to Ctl (p < 0.04). The levels of eCBs and Cnr1 expression are altered in a tissue-specific manner following a high-fat diet, and chronic exercise reverses some of these alterations. PMID:26880264

  4. Effect of a 1-week, eucaloric, moderately high-fat diet on peripheral insulin sensitivity in healthy premenopausal women

    Science.gov (United States)

    Branis, Natalia M; Etesami, Marjan; Walker, Ryan W; Berk, Evan S; Albu, Jeanine B

    2015-01-01

    Objectives To determine whether a weight-maintaining, moderate (50%) high-fat diet is deleterious to insulin sensitivity in healthy premenopausal women. Design/setting/participants 23 African-American and non-Hispanic white, healthy, overweight, and obese premenopausal women recruited in New York City, USA, fed either a eucaloric, 1-week long high-fat (50% of total Kcal from fat) diet or a eucaloric, 1-week long low-fat (30% of total Kcal from fat) diet, assigned in a randomized crossover design. Main outcome measures Peripheral insulin sensitivity and metabolic flexibility during a euglycemic hyperinsulinemic (80 mU/m2/min) clamp measured during the follicular phase of the menstrual cycle, at the end of each diet period. Results Peripheral insulin sensitivity (mg kg/fat-free mass/min (µU/mL)×10−1) was not decreased after the high-fat diet vs the low-fat diet (0.09±0.01 vs 0.08±0.01, p=0.09, respectively) in the combined group of African-American and white women, with no significant diet by race interaction (p=0.6). Metabolic flexibility (change in substrate utilization, ΔNPRQ, in response to insulin during the clamp) was similarly unaltered by the diet (0.12±0.01 vs 0.11, p=0.48, for the high-fat diet vs the low-fat diet, respectively) in the combined group of women, with no significant diet by race interaction (p=0.9). African–American women had a lower insulin clearance compared with the white women, regardless of the diet (p<0.05). Conclusions We conclude that a short term (1 week), moderate (50%), eucaloric high-fat diet does not lower peripheral insulin sensitivity in healthy, overweight and obese premenopausal women. PMID:26203360

  5. A study of acid phosphatase locus 1 in women with high fat content and normal body mass index.

    Science.gov (United States)

    De Lorenzo, Antonino; Di Renzo, Laura; Puja, Alberto; Saccucci, Patrizia; Gloria-Bottini, Fulvia; Bottini, Egidio

    2009-03-01

    De Lorenzo and coworkers have recently described a class of women with normal body mass index (BMI) and high fat content (normal weight obese syndrome [NWO]). This observation prompted us to study the possible role of acid phosphatase locus 1 (ACP(1)) in the differentiation of this special class of obese subjects. Acid phosphatase locus 1 is a polymorphic gene associated with severe obesity and with total cholesterol and triglycerides levels. The enzyme is composed by 2 isoforms--F and S--that have different biochemical properties and probably different functions. The sample study was composed of 130 white women from the population of Rome. Total fat mass and percentage of fat mass were measured by dual-energy x-ray absorptiometry. Thirty-six women had a BMI less than 25 and percentage of fat mass greater than 30 (high fat, normal BMI [HFHB]), and 94 women showed a BMI greater than 25 and a percentage of fat mass greater than 30 (high fat, high BMI [HFHB]). In the whole sample, the proportion of low-activity ACP(1) genotypes (*A/*A and *B/*A) was higher than in controls. However, whereas HFNB showed a very high frequency of ACP(1) *A/*A genotype, high-fat, high-BMI women showed an increase of *B/*A genotype. These 2 genotypes differ in the concentration of F isoform and the F/S ratio, which are lower in ACP(1)*A/*A genotype than in ACP(1)*B/*A genotype. The genetic differentiation of the class of women with normal BMI and high fat content from the class showing a concordant level of the 2 parameters supports the hypothesis that HFNB class represents a special cluster of obese subjects not revealed by BMI evaluation. Because ACP(1) is present in adipocytes, the present observation suggests that F isoform may have a specific role in the regulation of quantity of adipose tissue. PMID:19217450

  6. Soy protein is beneficial but high-fat diet and voluntary running are detrimental to bone structure in mice.

    Science.gov (United States)

    Yan, Lin; Graef, George L; Nielsen, Forrest H; Johnson, LuAnn K; Cao, Jay

    2015-06-01

    Physical activity and soy protein isolate (SPI) augmentation have been reported to be beneficial for bone health. We hypothesized that combining voluntary running and SPI intake would alleviate detrimental changes in bone induced by a high-fat diet. A 2 × 2 × 2 experiment was designed with diets containing 16% or 45% of energy as corn oil and 20% SPI or casein fed to sedentary or running male C57BL/6 mice for 14 weeks. Distal femurs were assessed for microstructural changes. The high-fat diet significantly decreased trabecular number (Tb.N) and bone mineral density (BMD) and increased trabecular separation (Tb.Sp). Soy protein instead of casein, regardless of fat content, in the diet significantly increased bone volume fraction, Tb.N, connectivity density, and BMD and decreased Tb.Sp. Voluntary running, regardless of fat content, significantly decreased bone volume fraction, Tb.N, connectivity density, and BMD and increased Tb.Sp. The high-fat diet significantly decreased osteocalcin and increased tartrate-resistant acid phosphatase 5b (TRAP 5b) concentrations in plasma. Plasma concentrations of osteocalcin were increased by both SPI and running. Running alleviated the increase in TRAP 5b induced by the high-fat diet. These findings demonstrate that a high-fat diet is deleterious, and SPI is beneficial to trabecular bone properties. The deleterious effect of voluntary running on trabecular structural characteristics indicates that there may be a maximal threshold of running beyond which beneficial effects cease and detrimental effects occur. Increases in plasma osteocalcin and decreases in plasma TRAP 5b in running mice suggest that a compensatory response occurs to counteract the detrimental effects of excessive running. PMID:25957968

  7. Effects of green tea (camellia sinensis on liver histology of mice on high fat diet: a morphometric study

    International Nuclear Information System (INIS)

    To evaluate the effects of green tea on liver histology of mice on high fat diet. Study Design: Analytical experimental randomized control trial. Place and Duration of Study: Department of Anatomy in collaboration with the Department of Pathology, Army Medical College, Rawalpindi and National Institute of Health, Islamabad. Twelve weeks study. Material and Methods: Sixty adult mice, Balb-c, strain were selected and divided into three groups. The control group was given standard laboratory diet throughout the study. In experimental group A, the study was carried out in two phases. In the first phase, hepatic steatosis was induced by high fat diet containing 4 percent cholesterol powder and 40 percent butter fat for six weeks. In the second phase, experimental group was given normal diet with 1 percent green tea over a period of next six weeks. The experimental group B was given high fat diet containing 4 percent cholesterol powder and 40 percent butter fat with 1 percent green tea over a period of twelve weeks. Ten mice in each group were sacrificed at six weeks and remaining ten were sacrificed at twelve weeks.Results: High fat diet for six weeks produced significant hepatic steatosis, evident on histological analysis. When experimental group A (induction phase) with high fat diet was compared with the (reversal phase) on normal diet and green tea, statistically significant difference (p<0.05) was noted in terms of liver histology. Green tea reverted all parameters in experimental group B, which though reduced never reached the control value and remained somewhat elevated. Conclusion: It is therefore concluded that green tea protects against the development of hepatic steatosis and reduces hepatic injury in mice. (author)

  8. Cell Suspension Culture of Eriobotrya japonica Regulates the Diabetic and Hyperlipidemic Signs of High-Fat-Fed Mice

    Directory of Open Access Journals (Sweden)

    Jin-Bin Wu

    2013-03-01

    Full Text Available The present study investigates the anti-hyperlipidemic and antihyperglycemic effects and mechanism in high-fat (HF-fed mice of cell suspension culture of Eriobotrya japonica (TA, which contains a great number of pentacyclic terpenoids. Firstly, C57BL/6J mice were randomly divided into two groups: the control (CON group was fed with a low-fat diet (n = 9, whereas the experimental group was fed a 45% HF diet for 8 weeks. Afterwards, the CON group was treated with vehicle, whereas the HF group was subdivided into five groups and was orally given TA or rosiglitazone or not for 4 weeks. Blood and visceral adipose tissue, liver tissue and skeletal muscle were examined. Treatment with TA reduced body weight gain, weights of white adipose tissue (WAT (including epididymal, perirenal, mesenteric WAT and visceral fat, and hepatic triacylglycerol content significantly without affecting food intake in diet-induced diabetic mice. TA effectively prevented HF diet-induced increases in the levels of blood glucose, insulin, leptin and HOMA-IR index (p < 0.001, p < 0.05, p < 0.05, p < 0.01, respectively and attenuated insulin resistance. Treatment with TA, adipocytes in the visceral depots showed a reduction in size. TA effectively significantly increased the protein contents of phosphorylation of AMPK-α (Thr172 both in liver and adipose tissue. It is shown that TA exhibits hypolipidemic effect in HF-fed mice by decreasing gene expressions of fatty acid synthesis, including acyl-coenzyme A: diacylglycerol acyltransferase (DGAT 2, which catalyzes the final step in the synthesis of triglycerides, and antidiabetic properties occurred as a result of decreased hepatic glucose production via phosphenolpyruvate carboxykinase (PEPCK down- regulation, improved insulin sensitization and TA (at 1.0 g/kg dose decreased expression of hepatic and adipose 11-β-hydroxysteroid dehydroxygenase (11β-HSD1 gene, which contributed in attenuating diabetic state. Futhermore, TA at

  9. Comparison of Dietary Control and Atorvastatin on High Fat Diet Induced Hepatic Steatosis and Hyperlipidemia in Rats

    Directory of Open Access Journals (Sweden)

    Liu Peiyi

    2011-01-01

    Full Text Available Abstract Background Treatment with atorvastatin (ATO or dietary control has been demonstrated to benefit patients with non-alcoholic fatty liver disease (NAFLD and hyperlipidemia. However, little is known on whether combination of dietary control and ATO treatment could enhance the therapeutic effect. Methods We employed a rat model of NAFLD to examine the therapeutic efficacy of dietary control and/or ATO treatment. Sprague-Dawley rats were fed with normal chow diet as normal controls or with high fat diet (HFD for 12 weeks to establish NAFLD. The NAFLD rats were randomized and continually fed with HFD, with normal chow diet, with HFD and treated with 30 mg/kg of ATO or with normal chow diet and treated with the same dose of ATO for 8 weeks. Subsequently, the rats were sacrificed and the serum lipids, aminotranferase, hepatic lipids, and liver pathology were characterized. The relative levels of fatty acid synthesis and β-oxidation gene expression in hepatic tissues were measured by quantitative real-time polymerase chain reaction (qRT-PCR. Hepatic expression of hydroxy-3-methylglutaryl coenzyme A (HMG-CoA reductase was determined by Western blot assay. Results While continual feeding with HFD deteriorated NAFLD and hyperlipidemia, treatment with dietary control, ATO or ATO with dietary control effectively improved serum and liver lipid metabolism and liver function. In comparison with ATO treatment, dietary control or combined with ATO treatment significantly reduced the liver weight and attenuated the HFD-induced hyperlipidemia and liver steatosis in rats. Compared to ATO treatment or dietary control, combination of ATO and dietary control significantly reduced the levels of serum total cholesterol and low density lipoprotein cholesterol (LDL-C. However, the combination therapy did not significantly improve triglyceride and free fatty acid metabolism, hepatic steatosis, and liver function, as compared with dietary control alone. Conclusions

  10. Berberine reduces cAMP-induced chloride secretion in T84 human colonic carcinoma cells through inhibition of basolateral KCNQ1 channels

    Directory of Open Access Journals (Sweden)

    BrianJosephHarvey

    2011-06-01

    Full Text Available Berberine is a plant alkaloid with multiple pharmacological actions, including antidiarrhoeal activity and has been shown to inhibit Cl- secretion in distal colon. The aims of this study were to determine the molecular signalling mechanisms of action of berberine on Cl- secretion and the ion transporter targets. Monolayers of T84 human colonic carcinoma cells grown in permeable supports were placed in Ussing chambers and short-circuit current measured in response to secretagogues and berberine. Whole-cell current recordings were performed in T84 cells using the patch-clamp technique. Berberine decreased forskolin-induced short-circuit current in a concentration-dependent manner (IC50 80  8 M. In apically permeabilized monolayers and whole-cell current recordings, berberine inhibited a cAMP-dependent and chromanol 293B-sensitive basolateral membrane K+ current by 88%, suggesting inhibition of KCNQ1 K+ channels. Berberine did not affect either apical Cl- conductance or basolateral Na+-K+-ATPase activity. Berberine stimulated p38 MAPK, PKC and PKA, but had no effect on p42/p44 MAPK and PKC. However, berberine pre-treatment prevented stimulation of p42/p44 MAPK by epidermal growth factor. The inhibitory effect of berberine on Cl- secretion was partially blocked by HBDDE (65 %, an inhibitor of PKC and to a smaller extent by inhibition of p38 MAPK with SB202190 (15 %. Berberine treatment induced an increase in association between PKC and PKA with KCNQ1 and produced phosphorylation of the channel. We conclude that berberine exerts its inhibitory effect on colonic Cl- secretion through inhibition of basolateral KCNQ1 channels responsible for K+ recycling via a PKC-dependent pathway.

  11. Berberine Reduces cAMP-Induced Chloride Secretion in T84 Human Colonic Carcinoma Cells through Inhibition of Basolateral KCNQ1 Channels.

    LENUS (Irish Health Repository)

    Alzamora, Rodrigo

    2011-01-01

    Berberine is a plant alkaloid with multiple pharmacological actions, including antidiarrhoeal activity and has been shown to inhibit Cl(-) secretion in distal colon. The aims of this study were to determine the molecular signaling mechanisms of action of berberine on Cl(-) secretion and the ion transporter targets. Monolayers of T84 human colonic carcinoma cells grown in permeable supports were placed in Ussing chambers and short-circuit current measured in response to secretagogues and berberine. Whole-cell current recordings were performed in T84 cells using the patch-clamp technique. Berberine decreased forskolin-induced short-circuit current in a concentration-dependent manner (IC(50) 80 ± 8 μM). In apically permeabilized monolayers and whole-cell current recordings, berberine inhibited a cAMP-dependent and chromanol 293B-sensitive basolateral membrane K(+) current by 88%, suggesting inhibition of KCNQ1 K(+) channels. Berberine did not affect either apical Cl(-) conductance or basolateral Na(+)-K(+)-ATPase activity. Berberine stimulated p38 MAPK, PKCα and PKA, but had no effect on p42\\/p44 MAPK and PKCδ. However, berberine pre-treatment prevented stimulation of p42\\/p44 MAPK by epidermal growth factor. The inhibitory effect of berberine on Cl(-) secretion was partially blocked by HBDDE (∼65%), an inhibitor of PKCα and to a smaller extent by inhibition of p38 MAPK with SB202190 (∼15%). Berberine treatment induced an increase in association between PKCα and PKA with KCNQ1 and produced phosphorylation of the channel. We conclude that berberine exerts its inhibitory effect on colonic Cl(-) secretion through inhibition of basolateral KCNQ1 channels responsible for K(+) recycling via a PKCα-dependent pathway.

  12. Berberine Reduces cAMP-Induced Chloride Secretion in T84 Human Colonic Carcinoma Cells through Inhibition of Basolateral KCNQ1 Channels.

    LENUS (Irish Health Repository)

    Alzamora, Rodrigo

    2012-02-01

    Berberine is a plant alkaloid with multiple pharmacological actions, including antidiarrhoeal activity and has been shown to inhibit Cl(-) secretion in distal colon. The aims of this study were to determine the molecular signaling mechanisms of action of berberine on Cl(-) secretion and the ion transporter targets. Monolayers of T84 human colonic carcinoma cells grown in permeable supports were placed in Ussing chambers and short-circuit current measured in response to secretagogues and berberine. Whole-cell current recordings were performed in T84 cells using the patch-clamp technique. Berberine decreased forskolin-induced short-circuit current in a concentration-dependent manner (IC(50) 80 +\\/- 8 muM). In apically permeabilized monolayers and whole-cell current recordings, berberine inhibited a cAMP-dependent and chromanol 293B-sensitive basolateral membrane K(+) current by 88%, suggesting inhibition of KCNQ1 K(+) channels. Berberine did not affect either apical Cl(-) conductance or basolateral Na(+)-K(+)-ATPase activity. Berberine stimulated p38 MAPK, PKCalpha and PKA, but had no effect on p42\\/p44 MAPK and PKCdelta. However, berberine pre-treatment prevented stimulation of p42\\/p44 MAPK by epidermal growth factor. The inhibitory effect of berberine on Cl(-) secretion was partially blocked by HBDDE ( approximately 65%), an inhibitor of PKCalpha and to a smaller extent by inhibition of p38 MAPK with SB202190 ( approximately 15%). Berberine treatment induced an increase in association between PKCalpha and PKA with KCNQ1 and produced phosphorylation of the channel. We conclude that berberine exerts its inhibitory effect on colonic Cl(-) secretion through inhibition of basolateral KCNQ1 channels responsible for K(+) recycling via a PKCalpha-dependent pathway.

  13. Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: a study to assess the drug's cardiac ion channel profile.

    Science.gov (United States)

    Koenig, Xaver; Kovar, Michael; Rubi, Lena; Mike, Agnes K; Lukacs, Peter; Gawali, Vaibhavkumar S; Todt, Hannes; Hilber, Karlheinz; Sandtner, Walter

    2013-12-01

    The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licensed as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channel profile in more detail, we studied the effects of ibogaine and its congener 18-Methoxycoronaridine (18-MC) on various cardiac voltage-gated ion channels. We confirmed that heterologously expressed hERG currents are reduced by ibogaine in low micromolar concentrations. Moreover, at higher concentrations, the drug also reduced human Nav1.5 sodium and Cav1.2 calcium currents. Ion currents were as well reduced by 18-MC, yet with diminished potency. Unexpectedly, although blocking hERG channels, ibogaine did not prolong the action potential (AP) in guinea pig cardiomyocytes at low micromolar concentrations. Higher concentrations (≥ 10 μM) even shortened the AP. These findings can be explained by the drug's calcium channel inhibition, which counteracts the AP-prolonging effect generated by hERG blockade. Implementation of ibogaine's inhibitory effects on human ion channels in a computer model of a ventricular cardiomyocyte, on the other hand, suggested that ibogaine does prolong the AP in the human heart. We conclude that therapeutic concentrations of ibogaine have the propensity to prolong the QT interval of the electrocardiogram in humans. In some cases this may lead to cardiac arrhythmias. PMID:23707769

  14. Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: A study to assess the drug's cardiac ion channel profile☆

    Science.gov (United States)

    Koenig, Xaver; Kovar, Michael; Rubi, Lena; Mike, Agnes K.; Lukacs, Peter; Gawali, Vaibhavkumar S.; Todt, Hannes; Hilber, Karlheinz; Sandtner, Walter

    2013-01-01

    The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licenced as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channel profile in more detail, we studied the effects of ibogaine and its congener 18-Methoxycoronaridine (18-MC) on various cardiac voltage-gated ion channels. We confirmed that heterologously expressed hERG currents are reduced by ibogaine in low micromolar concentrations. Moreover, at higher concentrations, the drug also reduced human Nav1.5 sodium and Cav1.2 calcium currents. Ion currents were as well reduced by 18-MC, yet with diminished potency. Unexpectedly, although blocking hERG channels, ibogaine did not prolong the action potential (AP) in guinea pig cardiomyocytes at low micromolar concentrations. Higher concentrations (≥ 10 μM) even shortened the AP. These findings can be explained by the drug's calcium channel inhibition, which counteracts the AP-prolonging effect generated by hERG blockade. Implementation of ibogaine's inhibitory effects on human ion channels in a computer model of a ventricular cardiomyocyte, on the other hand, suggested that ibogaine does prolong the AP in the human heart. We conclude that therapeutic concentrations of ibogaine have the propensity to prolong the QT interval of the electrocardiogram in humans. In some cases this may lead to cardiac arrhythmias. PMID:23707769

  15. Inhibition of SK4 Potassium Channels Suppresses Cell Proliferation, Migration and the Epithelial-Mesenchymal Transition in Triple-Negative Breast Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Panshi Zhang

    Full Text Available Treatments for triple-negative breast cancer (TNBC are limited; intermediate-conductance calcium-activated potassium (SK4 channels are closely involved in tumor progression, but little is known about these channels in TNBC. We aimed to investigate whether SK4 channels affect TNBC. First, by immunohistochemistry (IHC and western blotting (WB, increased SK4 protein expression in breast tumor tissues was detected relative to that in non-tumor breast tissues, but there was no apparent expression difference between various subtypes of breast cancer (p>0.05. Next, functional SK4 channels were detected in the TNBC cell line MDA-MB-231 using WB, real-time PCR, immunofluorescence and patch-clamp recording. By employing SK4 specific siRNAs and blockers, including TRAM-34 and clotrimazole, in combination with an MTT assay, a colony-formation assay, flow cytometry and a cell motility assay, we found that the suppression of SK4 channels significantly inhibited cell proliferation and migration and promoted apoptosis in MDA-MB-231 cells (p<0.05. Further investigation revealed that treatment with epidermal growth factor (EGF/basic fibroblast growth factor (bFGF caused MDA-MB-231 cells to undergo the epithelial-mesenchymal transition (EMT and to show increased SK4 mRNA expression. In addition, the down-regulation of SK4 expression inhibited the EMT markers Vimentin and Snail1. Collectively, our findings suggest that SK4 channels are expressed in TNBC and are involved in the proliferation, apoptosis, migration and EMT processes of TNBC cells.

  16. Inhibition of collagen synthesis by select calcium and sodium channel blockers can be mitigated by ascorbic acid and ascorbyl palmitate

    OpenAIRE

    Ivanov, Vadim; Ivanova, Svetlana; KALINOVSKY, TATIANA; NIEDZWIECKI, ALEKSANDRA; RATH, MATTHIAS

    2016-01-01

    Calcium, sodium and potassium channel blockers are widely prescribed medications for a variety of health problems, most frequently for cardiac arrhythmias, hypertension, angina pectoris and other disorders. However, chronic application of channel blockers is associated with numerous side effects, including worsening cardiac pathology. For example, nifedipine, a calcium-channel blocker was found to be associated with increased mortality and increased risk for myocardial infarction. In addition...

  17. Molecular Mechanism of Sulphonylurea Block of KATP Channels Carrying Mutations That Impair ATP Inhibition and Cause Neonatal Diabetes

    OpenAIRE

    Proks, Peter; de Wet, Heidi; Ashcroft, Frances M

    2013-01-01

    Sulphonylurea drugs are the therapy of choice for treating neonatal diabetes (ND) caused by mutations in the ATP-sensitive K+ channel (KATP channel). We investigated the interactions between MgATP, MgADP, and the sulphonylurea gliclazide with KATP channels expressed in Xenopus oocytes. In the absence of MgATP, gliclazide block was similar for wild-type channels and those carrying the Kir6.2 ND mutations R210C, G334D, I296L, and V59M. Gliclazide abolished the stimulatory effect of MgATP on all...

  18. Synergistic antiarrhythmic effect of combining inhibition of Ca(2+)-activated K(+) (SK) channels and voltage-gated Na(+) channels in an isolated heart model of atrial fibrillation

    DEFF Research Database (Denmark)

    Kirchhoff, Jeppe Egedal; Goldin Diness, Jonas; Sheykhzade, Majid;

    2015-01-01

    would be subefficacious as monotherapy, may prevent atrial fibrillation (AF) and have reduced proarrhythmic potential in the ventricles. METHODS: Subefficacious concentrations of ranolazine, flecainide, and lidocaine were tested alone or in combination with the SK channel blocker N-(pyridin-2-yl)-4...

  19. Direct autocrine inhibition and cAMP-dependent potentiation of single L-type Ca2+ channels in bovine chromaffin cells.

    Science.gov (United States)

    Carabelli, V; Hernández-Guijo, J M; Baldelli, P; Carbone, E

    2001-04-01

    Using the cell-attached recording configuration, we found that in adult bovine chromaffin cells there exists a direct membrane-delimited inhibition of single Bay K-modified L-channels mediated by opioids and ATP locally released in the recording pipette. This autocrine modulation is mediated by pertussis toxin (PTX)-sensitive G-proteins and causes a 50 % decrease of the open channel probability (Po) and an equivalent percentage increase of null sweeps at +10 mV with no changes to the activation kinetics, single channel conductance and mean open time. The decrease in Po is mainly due to an increase in the occurrence and duration of slow closed times (> 40 ms). Addition of purinergic and opioidergic antagonists (suramin and naloxone) or cell pre-treatment with PTX removes the inhibition while addition of ATP and opioids inside the pipette, but not outside, mimics the effect. Strong pre-pulses (+150 mV, 280 ms) followed by short repolarizations are unable to remove the inhibition at test potential (+10 mV). Increasing the level of cAMP by either direct application of 8-(4-chlorophenylthio)-cAMP (8-CPT-cAMP) or mixtures of forskolin and 1-methyl-3-isobutylxanthine (IBMX) potentiates the activity of L-channels by increasing the mean open time and decreasing the mean closed time and percentage of null sweeps. The cAMP-induced potentiation occurs regardless of whether the G-protein-mediated inhibition is activated by ATP and opioids or inactivated by PTX. Protein kinase inhibitors (H7 and H89) prevent the effects of cAMP without altering the basal autocrine modulation associated with PTX-sensitive G-proteins. Our results provide new evidence for the coexistence of two distinct modulations that may converge on the same neuroendocrine L-channel: a direct G-protein-dependent inhibition and a cAMP-mediated potentiation, which may work in combination to regulate Ca2+ entry during neurosecretion. PMID:11283226

  20. Restricted feeding of a high-fat diet reduces spontaneous metastases of Lewis lung carcinoma in C57BL/6 mice

    Science.gov (United States)

    Obesity is a risk factor for cancer. We previously reported that consumption of a high-fat diet enhances metastasis in mice (Yan, Clin Exp Metastasis 2010). The present study investigated the effects of restricted feeding of a high-fat diet on spontaneous metastasis of Lewis lung carcinoma (LLC) i...

  1. Effects of Persian leek (Allium ampeloprasum) on hepatic lipids and the expression of proinflammatory gene in hamsters fed a high-fat/ high-cholesterol diet

    Science.gov (United States)

    Fatoorechi, Vahideh; Rismanchi, Marjan; Nasrollahzadeh, Javad

    2016-01-01

    Objective: Persian leek is one of the most widely used herbal foods among Iranians. In this study, effects of oral administration of Persian leek on plasma and liver lipids were examined in hamster. Materials and Methods: Male Syrian hamsters were randomly divided into three groups: control (standard diet), high fat control (high-fat/high-cholesterol diet), Persian leek (high-fat/high-cholesterol diet + 1% per weight of diet from dried powdered Persian leek) for 14 weeks. Results: High fat diet increased plasma and liver lipids as compared to standard diet. Adding Persian leek to the high-fat/high-cholesterol diet resulted in no significant changes in the concentration of the plasma lipids or liver cholesterol. However, liver triglycerides (TG), plasma Alanine aminotransferase and gene expression of tumor necrosis factor- α were decreased in hamsters fed high-fat diet containing Persian leek as compared to high-fat diet only. Conclusion: Persian leek might be considered as a herbal food that can reduce liver TG accumulation induced by high fat diets.

  2. Nitric oxide inhibits neuroendocrine CaV1 L-channel gating via cGMP-dependent protein kinase in cell-attached patches of bovine chromaffin cells

    Science.gov (United States)

    Carabelli, Valentina; D'Ascenzo, Marcello; Carbone, Emilio; Grassi, Claudio

    2002-01-01

    Nitric oxide (NO) regulates the release of catecholamines from the adrenal medulla but the molecular targets of its action are not yet well identified. Here we show that the NO donor sodium nitroprusside (SNP, 200 μM) causes a marked depression of the single CaV1 L-channel activity in cell-attached patches of bovine chromaffin cells. SNP action was complete within 3-5 min of cell superfusion. In multichannel patches the open probability (NPo) decreased by ∼60 % between 0 and +20 mV. Averaged currents over a number of traces were proportionally reduced and showed no drastic changes to their time course. In single-channel patches the open probability (Po) at +10 mV decreased by the same amount as that of multichannel patches (∼61 %). Such a reduction was mainly associated with an increased probability of null sweeps and a prolongation of mean shut times, while first latency, mean open time and single-channel conductance were not significantly affected. Addition of the NO scavenger carboxy-PTIO or cell treatment with the guanylate cyclase inhibitor ODQ prevented the SNP-induced inhibition. 8-Bromo-cyclicGMP (8-Br-cGMP; 400 μM) mimicked the action of the NO donor and the protein kinase G blocker KT-5823 prevented this effect. The depressive action of SNP was preserved after blocking the cAMP-dependent up-regulatory pathway with the protein kinase A inhibitor H89. Similarly, the inhibitory action of 8-Br-cGMP proceeded regardless of the elevation of cAMP levels, suggesting that cGMP/PKG and cAMP/PKA act independently on L-channel gating. The inhibitory action of 8-Br-cGMP was also independent of the G protein-induced inhibition of L-channels mediated by purinergic and opiodergic autoreceptors. Since Ca2+ channels contribute critically to both the local production of NO and catecholamine release, the NO/PKG-mediated inhibition of neuroendocrine L-channels described here may represent an important autocrine signalling mechanism for controlling the rate of

  3. Nitric oxide inhibits neuroendocrine Ca(V)1 L-channel gating via cGMP-dependent protein kinase in cell-attached patches of bovine chromaffin cells.

    Science.gov (United States)

    Carabelli, Valentina; D'Ascenzo, Marcello; Carbone, Emilio; Grassi, Claudio

    2002-06-01

    Nitric oxide (NO) regulates the release of catecholamines from the adrenal medulla but the molecular targets of its action are not yet well identified. Here we show that the NO donor sodium nitroprusside (SNP, 200 microM) causes a marked depression of the single Ca(V)1 L-channel activity in cell-attached patches of bovine chromaffin cells. SNP action was complete within 3-5 min of cell superfusion. In multichannel patches the open probability (NP(o)) decreased by approximately 60 % between 0 and +20 mV. Averaged currents over a number of traces were proportionally reduced and showed no drastic changes to their time course. In single-channel patches the open probability (P(o)) at +10 mV decreased by the same amount as that of multichannel patches (approximately 61 %). Such a reduction was mainly associated with an increased probability of null sweeps and a prolongation of mean shut times, while first latency, mean open time and single-channel conductance were not significantly affected. Addition of the NO scavenger carboxy-PTIO or cell treatment with the guanylate cyclase inhibitor ODQ prevented the SNP-induced inhibition. 8-Bromo-cyclicGMP (8-Br-cGMP; 400 microM) mimicked the action of the NO donor and the protein kinase G blocker KT-5823 prevented this effect. The depressive action of SNP was preserved after blocking the cAMP-dependent up-regulatory pathway with the protein kinase A inhibitor H89. Similarly, the inhibitory action of 8-Br-cGMP proceeded regardless of the elevation of cAMP levels, suggesting that cGMP/PKG and cAMP/PKA act independently on L-channel gating. The inhibitory action of 8-Br-cGMP was also independent of the G protein-induced inhibition of L-channels mediated by purinergic and opiodergic autoreceptors. Since Ca(2+) channels contribute critically to both the local production of NO and catecholamine release, the NO/PKG-mediated inhibition of neuroendocrine L-channels described here may represent an important autocrine signalling mechanism

  4. Sechium edule Shoot Extracts and Active Components Improve Obesity and a Fatty Liver That Involved Reducing Hepatic Lipogenesis and Adipogenesis in High-Fat-Diet-Fed Rats.

    Science.gov (United States)

    Yang, Mon-Yuan; Chan, Kuei-Chuan; Lee, Yi-Ju; Chang, Xiao-Zong; Wu, Cheng-Hsun; Wang, Chau-Jong

    2015-05-13

    Excess fat accumulation in the liver increases the risk of developing progressive liver injuries ranging from a fatty liver to hepatocarcinoma. In a previous study, we demonstrated that the polyphenol components of Sechium edule shoots attenuated hepatic lipid accumulation in vitro. Therefore, we investigated the effects and mechanisms of the extract of S. edule shoots (SWE) to modulate fat accumulation in a high-fat-diet (HFD)-induced animal model. In this study, we found that the SWE can reduce the body weight, adipose tissue fat, and regulate hepatic lipid contents (e.g., triglyceride and cholesterol). Additionally, treatment of caffeic acid (CA) and hesperetin (HPT), the main ingredients of SWE, also inhibited oleic acid (OA)-induced lipid accumulation in HepG2 cells. SWE enhanced the activation of AMP-activating protein kinase (AMPK) and decreased numerous lipogenic-related enzymes, such as sterol regulator element-binding proteins (SREBPs), e.g., SREBP-1 and SREBP-2, and HMG-CoA reductase (HMGCoR) proteins, which are critical regulators of hepatic lipid metabolism. Taken together, the results demonstrated that SWE can prevent a fatty liver and attenuate adipose tissue fat by inhibiting lipogenic enzymes and stimulating lipolysis via upregulating AMPK. It was also demonstrated that the main activation components of SWE are both CA and HPT. PMID:25912298

  5. Impaired glucose tolerance in rats fed low-carbohydrate, high-fat diets.

    Science.gov (United States)

    Bielohuby, Maximilian; Sisley, Stephanie; Sandoval, Darleen; Herbach, Nadja; Zengin, Ayse; Fischereder, Michael; Menhofer, Dominik; Stoehr, Barbara J M; Stemmer, Kerstin; Wanke, Rüdiger; Tschöp, Matthias H; Seeley, Randy J; Bidlingmaier, Martin

    2013-11-01

    Moderate low-carbohydrate/high-fat (LC-HF) diets are widely used to induce weight loss in overweight subjects, whereas extreme ketogenic LC-HF diets are used to treat neurological disorders like pediatric epilepsy. Usage of LC-HF diets for improvement of glucose metabolism is highly controversial; some studies suggest that LC-HF diets ameliorate glucose tolerance, whereas other investigations could not identify positive effects of these diets or reported impaired insulin sensitivity. Here, we investigate the effects of LC-HF diets on glucose and insulin metabolism in a well-characterized animal model. Male rats were fed isoenergetic or hypocaloric amounts of standard control diet, a high-protein "Atkins-style" LC-HF diet, or a low-protein, ketogenic, LC-HF diet. Both LC-HF diets induced lower fasting glucose and insulin levels associated with lower pancreatic β-cell volumes. However, dynamic challenge tests (oral and intraperitoneal glucose tolerance tests, insulin-tolerance tests, and hyperinsulinemic euglycemic clamps) revealed that LC-HF pair-fed rats exhibited impaired glucose tolerance and impaired hepatic and peripheral tissue insulin sensitivity, the latter potentially being mediated by elevated intramyocellular lipids. Adjusting visceral fat mass in LC-HF groups to that of controls by reducing the intake of LC-HF diets to 80% of the pair-fed groups did not prevent glucose intolerance. Taken together, these data show that lack of dietary carbohydrates leads to glucose intolerance and insulin resistance in rats despite causing a reduction in fasting glucose and insulin concentrations. Our results argue against a beneficial effect of LC-HF diets on glucose and insulin metabolism, at least under physiological conditions. Therefore, use of LC-HF diets for weight loss or other therapeutic purposes should be balanced against potentially harmful metabolic side effects. PMID:23982154

  6. Changes in milk composition in obese rats consuming a high-fat diet.

    Science.gov (United States)

    Bautista, C J; Montaño, S; Ramirez, V; Morales, A; Nathanielsz, P W; Bobadilla, N A; Zambrano, E

    2016-02-14

    Maternal obesity programmes offspring development. We addressed maternal obesity effects induced by high-fat diets on maternal mammary gland (MG) structure and function and offspring brain, liver and fat outcomes. Mothers were fed control (C, n 5) or obesogenic (MO, n 5) diet from the time they were weaned through pregnancy beginning at 120 d, through lactation. At offspring postnatal day (PND) 20, milk leptin and nutrients were determined. At the end of lactation, maternal liver and MG fatty acid profile were measured. Desaturase (Δ6D and Δ5D) and elongase (ELOVL 5 and ELOVL 2) protein was measured by immunohistochemistry and Western blotting (WB) in the liver and WB in the MG. In mothers, liver, MG and milk fat content were higher in MO than in C. Liver arachidonic acid (AA) and EPA and MG EPA were lower in MO than in C. Liver desaturases were higher in MO. The MG was heavier in MO than in C, with decreased Δ5D expression in MO. Desaturases and elongases were immunolocalised in parenchymal cells of both groups. Milk yield, water, carbohydrate content, EPA and DHA were lower, whereas milk leptin and AA were higher in MO than in C. At PND 21 and 36, brain weight was less and fat depots were greater in MO offspring than in C. MO decreased male absolute brain weight but not female absolute brain weight. In conclusion, maternal obesity induced by an obesogenic diet negatively affects maternal liver and MG function with the production of significant changes in milk composition. Maternal obesity adversely affects offspring metabolism and development. PMID:26608475

  7. High fat diet-fed obese rats are highly sensitive to doxorubicin-induced cardiotoxicity

    International Nuclear Information System (INIS)

    Often, chemotherapy by doxorubicin (Adriamycin) is limited due to life threatening cardiotoxicity in patients during and posttherapy. Recently, we have shown that moderate diet restriction remarkably protects against doxorubicin-induced cardiotoxicity. This cardioprotection is accompanied by decreased cardiac oxidative stress and triglycerides and increased cardiac fatty-acid oxidation, ATP synthesis, and upregulated JAK/STAT3 pathway. In the current study, we investigated whether a physiological intervention by feeding 40% high fat diet (HFD), which induces obesity in male Sprague-Dawley rats (250-275 g), sensitizes to doxorubicin-induced cardiotoxicity. A LD10 dose (8 mg doxorubicin/kg, ip) administered on day 43 of the HFD feeding regimen led to higher cardiotoxicity, cardiac dysfunction, lipid peroxidation, and 80% mortality in the obese (OB) rats in the absence of any significant renal or hepatic toxicity. Doxorubicin toxicokinetics studies revealed no change in accumulation of doxorubicin and doxorubicinol (toxic metabolite) in the normal diet-fed (ND) and OB hearts. Mechanistic studies revealed that OB rats are sensitized due to: (1) higher oxyradical stress leading to upregulation of uncoupling proteins 2 and 3, (2) downregulation of cardiac peroxisome proliferators activated receptor-α, (3) decreased plasma adiponectin levels, (4) decreased cardiac fatty-acid oxidation (666.9 ± 14.0 nmol/min/g heart in ND versus 400.2 ± 11.8 nmol/min/g heart in OB), (5) decreased mitochondrial AMP-α2 protein kinase, and (6) 86% drop in cardiac ATP levels accompanied by decreased ATP/ADP ratio after doxorubicin administration. Decreased cardiac erythropoietin and increased SOCS3 further downregulated the cardioprotective JAK/STAT3 pathway. In conclusion, HFD-induced obese rats are highly sensitized to doxorubicin-induced cardiotoxicity by substantially downregulating cardiac mitochondrial ATP generation, increasing oxidative stress and downregulating the JAK/STAT3

  8. Morin attenuates hepatic insulin resistance in high-fat-diet-induced obese mice.

    Science.gov (United States)

    Naowaboot, Jarinyaporn; Wannasiri, Supaporn; Pannangpetch, Patchareewan

    2016-06-01

    Morin is a natural bioflavonoid that exhibits antioxidant and anti-inflammatory properties. The present study was designed to evaluate the effect of morin on insulin resistance, oxidative stress, and inflammation in a high-fat-diet (HFD)-induced obese mice. Obesity was induced in ICR mice by feeding a HFD (60 % kcal from fat) for 12 weeks. After the first 6 weeks, obese mice were treated with morin (50 or 100 mg/kg/day) once daily for further 6 weeks. Blood glucose, lipid profile, insulin, leptin, adiponectin, and markers of oxidative stress and inflammation were then measured. Liver was excised, subjected to histopathology, glycogen determination, and gene and protein expression analysis. Morin administration reduced blood glucose, serum insulin, leptin, malondialdehyde, interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1) levels and increased serum adiponectin levels. Moreover, there was a reduction in serum lipid and liver triglyceride levels. Liver histology indicated that morin limited accumulation of lipid droplets. Interestingly, morin reduced expression of hepatic sterol regulatory element binding protein 1c (SREBP1c), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC) and up-regulated hepatic carnitine palmitoyltransferase 1a (CPT1a) expression. Morin also stimulated glycogen storage and suppressed phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) protein expression. Furthermore, hepatic superoxide dismutase (SOD) and catalase (CAT) expression were increased after morin treatment. These findings indicate that morin has a positive effect in the HFD-induced obesity condition by suppressing lipogenesis, gluconeogenesis, inflammation, and oxidative stress activities. PMID:26976296

  9. Fruit juice drinks prevent endogenous antioxidant response to high-fat meal ingestion.

    Science.gov (United States)

    Miglio, Cristiana; Peluso, Ilaria; Raguzzini, Anna; Villaño, Deborah V; Cesqui, Eleonora; Catasta, Giovina; Toti, Elisabetta; Serafini, Mauro

    2014-01-28

    High-fat meals (HFM) induce metabolic stress, leading to the activation of protective mechanisms, including inflammation and endogenous antioxidant defences. In the present study, we investigated the effects of antioxidant-rich fruit juice drinks on the endogenous antioxidant response induced by HFM. In a double-blind, cross-over design (10 d washout), fourteen overweight volunteers were randomly assigned to one of the following interventions: HFM+500 ml placebo beverage (HFM-PB, free from fruit); HFM+500 ml antioxidant beverage 1 (HFM-AB1; apple, grape, blueberry and pomegranate juices and grape skin, grape seed and green tea extracts); HFM+500 ml antioxidant beverage 2 (HFM-AB2; pineapple, black currant and plum juices). HFM-PB consumption increased the plasma levels of thiols (SH) (4 h, Ptrapping antioxidant parameter (TRAP) (4 h, PTRAP (2 h, P< 0·001) and urinary ferric reducing antioxidant power (0-8 h, P< 0·01) were increased by HFM-AB1 consumption, the drink with the highest in vitro antioxidant capacity, but not by HFM-AB2 consumption. In urine, UA levels were significantly increased from basal levels after the consumption of HFM-PB and HFM-AB2. However, neither of the beverages increased the urinary excretion of UA with respect to the placebo beverage. In conclusion, the increase in UA and SH levels induced by HFM as part of an endogenous antioxidant response to postprandial stress can be prevented by the concomitant ingestion of antioxidant-rich fruit juice drinks. PMID:23930843

  10. High fat diet alters lactation outcomes: possible involvement of inflammatory and serotonergic pathways.

    Directory of Open Access Journals (Sweden)

    Laura L Hernandez

    Full Text Available Delay in the onset of lactogenesis has been shown to occur in women who are obese, however the mechanism altered within the mammary gland causing the delay remains unknown. Consumption of high fat diets (HFD has been previously determined to result decreased litters and litter numbers in rodent models due to a decrease in fertility. We examined the effects of feeding a HFD (60% kcal from fat diet versus a low-fat diet (LFD; 10% kcal from fat to female Wistar rats on lactation outcomes. Feeding of HFD diet resulted in increased pup weights compared to pups from LFD fed animals for 4 d post-partum. Lactation was delayed in mothers on HFD but they began to produce copious milk volumes beginning 2 d post-partum, and milk yield was similar to LFD by day 3. Mammary glands collected from lactating animals on HFD diet, displayed a disrupted morphologies, with very few and small alveoli. Consistently, there was a significant decrease in the mRNA expression of milk protein genes, glucose transporter 1 (GLUT1 and keratin 5 (K5, a luminobasal cell marker in the mammary glands of HFD lactating animals. Expression of tryptophan hydroxylase 1 (TPH1, the rate-limiting enzyme in serotonin (5-HT biosynthesis, and the 5-HT(7 receptor (HTR7, which regulates mammary gland involution, were significantly increased in mammary glands of HFD animals. Additionally, we saw elevation of the inflammatory markers interleukin-6 (IL-6 and tumor necrosis factor-α (TNF- α. These results indicate that consumption of HFD impairs mammary parenchymal tissue and impedes its ability to synthesize and secrete milk, possibly through an increase in 5-HT production within the mammary gland leading to an inflammatory process.

  11. Spatial Cognition in Adult and Aged Mice Exposed to High-Fat Diet.

    Science.gov (United States)

    Kesby, James P; Kim, Jane J; Scadeng, Miriam; Woods, Gina; Kado, Deborah M; Olefsky, Jerrold M; Jeste, Dilip V; Achim, Cristian L; Semenova, Svetlana

    2015-01-01

    Aging is associated with a decline in multiple aspects of cognitive function, with spatial cognition being particularly sensitive to age-related decline. Environmental stressors, such as high-fat diet (HFD) exposure, that produce a diabetic phenotype and metabolic dysfunction may indirectly lead to exacerbated brain aging and promote the development of cognitive deficits. The present work investigated whether exposure to HFD exacerbates age-related cognitive deficits in adult versus aged mice. Adult (5 months old) and aged (15 months old) mice were exposed to control diet or HFD for three months prior to, and throughout, behavioral testing. Anxiety-like behavior in the light-dark box test, discrimination learning and memory in the novel object/place recognition tests, and spatial learning and memory in the Barnes maze test were assessed. HFD resulted in significant gains in body weight and fat mass content with adult mice gaining significantly more weight and adipose tissue due to HFD than aged mice. Weight gain was attributed to food calories sourced from fat, but not total calorie intake. HFD increased fasting insulin levels in all mice, but adult mice showed a greater increase relative to aged mice. Behaviorally, HFD increased anxiety-like behavior in adult but not aged mice without significantly affecting spatial cognition. In contrast, aged mice fed either control or HFD diet displayed deficits in novel place discrimination and spatial learning. Our results suggest that adult mice are more susceptible to the physiological and anxiety-like effects of HFD consumption than aged mice, while aged mice displayed deficits in spatial cognition regardless of dietary influence. We conclude that although HFD induces systemic metabolic dysfunction in both adult and aged mice, overall cognitive function was not adversely affected under the current experimental conditions. PMID:26448649

  12. Spatial Cognition in Adult and Aged Mice Exposed to High-Fat Diet.

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    James P Kesby

    Full Text Available Aging is associated with a decline in multiple aspects of cognitive function, with spatial cognition being particularly sensitive to age-related decline. Environmental stressors, such as high-fat diet (HFD exposure, that produce a diabetic phenotype and metabolic dysfunction may indirectly lead to exacerbated brain aging and promote the development of cognitive deficits. The present work investigated whether exposure to HFD exacerbates age-related cognitive deficits in adult versus aged mice. Adult (5 months old and aged (15 months old mice were exposed to control diet or HFD for three months prior to, and throughout, behavioral testing. Anxiety-like behavior in the light-dark box test, discrimination learning and memory in the novel object/place recognition tests, and spatial learning and memory in the Barnes maze test were assessed. HFD resulted in significant gains in body weight and fat mass content with adult mice gaining significantly more weight and adipose tissue due to HFD than aged mice. Weight gain was attributed to food calories sourced from fat, but not total calorie intake. HFD increased fasting insulin levels in all mice, but adult mice showed a greater increase relative to aged mice. Behaviorally, HFD increased anxiety-like behavior in adult but not aged mice without significantly affecting spatial cognition. In contrast, aged mice fed either control or HFD diet displayed deficits in novel place discrimination and spatial learning. Our results suggest that adult mice are more susceptible to the physiological and anxiety-like effects of HFD consumption than aged mice, while aged mice displayed deficits in spatial cognition regardless of dietary influence. We conclude that although HFD induces systemic metabolic dysfunction in both adult and aged mice, overall cognitive function was not adversely affected under the current experimental conditions.

  13. N-Acetylneuraminic acid attenuates hypercoagulation on high fat diet-induced hyperlipidemic rats

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    Zhang Yida

    2015-12-01

    Full Text Available Background and objective: N-Acetylneuraminic acid (Neu5Ac, a type of sialic acid, has close links with cholesterol metabolism and is often used as a biomarker in evaluating the risk of cardiovascular diseases. However, most studies on the health implications of Neu5Ac have focused on its effects on the nervous system, while its effects on cardiovascular risk factors have largely been unreported. Thus, the effects of Neu5Ac on coagulation status in high fat diet (HFD-induced hyperlipidemic rats were evaluated in this study. Methods: Sprague Dawley male rats were divided into five different groups and fed with HFD alone, HFD low-dose Neu5Ac, HFD high-dose Neu5Ac, HFD simvastatin (10 mg/kg day, and normal pellet alone. Food was given ad libitum while body weight of rats was measured weekly. After 12 weeks of intervention, rats were sacrificed and serum and tissue samples were collected for biochemistry and gene expression analysis, respectively. Results: The results showed that Neu5Ac could improve lipid metabolism and hyperlipidemia-associated coagulation. Neu5Ac exerted comparable or sometimes better physiological effects than simvastatin, at biochemical and gene expression levels. Conclusions: The data indicated that Neu5Ac prevented HFD-induced hyperlipidemia and associated hypercoagulation in rats through regulation of lipid-related and coagulation-related genes and, by extension, induced metabolite and protein changes. The implications of the present findings are that Neu5Ac may be used to prevent coagulation-related cardiovascular events in hyperlipidemic conditions. These findings are worth studying further.

  14. Hsp70 plays an important role in high-fat diet induced gestational hyperglycemia in mice.

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    Xing, Baoheng; Wang, Lili; Li, Qin; Cao, Yalei; Dong, Xiujuan; Liang, Jun; Wu, Xiaohua

    2015-12-01

    Gestational diabetes mellitus (GDM) has emerged as an epidemic disease during the last decade, affecting about 2 to 5% pregnant women. Even among women who have gestational hyperglycemia may also be positively related to adverse outcomes as GDM. Since heat shock protein (Hsp) 70 has been reported to be associated with diabetes and insulin resistance and its expression was reported to be negatively regulated by the membrane-permeable Hsp70 inhibitor MAL3-101 while positively regulated by the Hsp70 activator BGP-15, we investigated whether Hsp70 played a role in a gestational hyperglycemia mouse model. Mice were divided into non-pregnant and pregnant groups, and each comprised three subgroups: control, high-fat diet (HFD) + MAL3-101, and HFD + BGP-15. We examined the serum levels of triglycerides, total cholesterol, glucose, and insulin, as well as conducted thermal detection of brown adipose tissue (BAT). The role of Hsp70 in BAT apoptosis was also investigated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and caspase-3 staining. Higher serum level of Hsp70 was associated with increased bodyweight gain after pregnancy in mice fed HFD. Circulating Hsp70 was elevated in control pregnant mice compared to control non-pregnant mice. BGP-induced serum Hsp70 expression reduced triglycerides, total cholesterol, glucose, and insulin levels in the serum. Additionally, thermal detection of BAT, TUNEL, and caspase-3 staining revealed relationship correlation between Hsp70 and BAT functions. Hsp70 level is associated with hyperglycemia during pregnancy. Our results support the role of Hsp70 in facilitating BAT activities and protecting BAT cells from apoptosis via caspase-3 pathway. PMID:26318018

  15. MicroRNA Expression Signature Is Altered in the Cardiac Remodeling Induced by High Fat Diets.

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    Guedes, Elaine Castilho; França, Gustavo Starvaggi; Lino, Caroline Antunes; Koyama, Fernanda Christtanini; Moreira, Luana do Nascimento; Alexandre, Juliana Gomes; Barreto-Chaves, Maria Luiza M; Galante, Pedro Alexandre Favoretto; Diniz, Gabriela Placoná

    2016-08-01

    Recent studies have revealed the involvement of microRNAs (miRNAs) in the control of cardiac hypertrophy and myocardial function. In addition, several reports have demonstrated that high fat (HF) diet induces cardiac hypertrophy and remodeling. In the current study, we investigated the effect of diets containing different percentages of fat on the cardiac miRNA expression signature. To address this question, male C57Bl/6 mice were fed with a low fat (LF) diet or two HF diets, containing 45 kcal% fat (HF45%) and 60 kcal% fat (HF60%) for 10 and 20 weeks. HF60% diet promoted an increase on body weight, fasting glycemia, insulin, leptin, total cholesterol, triglycerides, and induced glucose intolerance. HF feeding promoted cardiac remodeling, as evidenced by increased cardiomyocyte transverse diameter and interstitial fibrosis. RNA sequencing analysis demonstrated that HF feeding induced distinct miRNA expression patterns in the heart. HF45% diet for 10 and 20 weeks changed the abundance of 64 and 26 miRNAs in the heart, respectively. On the other hand, HF60% diet for 10 and 20 weeks altered the abundance of 27 and 88 miRNAs in the heart, respectively. Bioinformatics analysis indicated that insulin signaling pathway was overrepresented in response to HF diet. An inverse correlation was observed between cardiac levels of GLUT4 and miRNA-29c. Similarly, we found an inverse correlation between expression of GSK3β and the expression of miRNA-21a-3p, miRNA-29c-3p, miRNA-144-3p, and miRNA-195a-3p. In addition, miRNA-1 overexpression prevented cardiomyocyte hypertrophy. Taken together, our results revealed differentially expressed miRNA signatures in the heart in response to different HF diets. J. Cell. Physiol. 231: 1771-1783, 2016. © 2015 Wiley Periodicals, Inc. PMID:26638879

  16. Effect of Bougainvillea spectabilis Leaves on Serum Lipids in Albino Rats Fed with High Fat Diet

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    H. Saikia

    2011-04-01

    Full Text Available Dyslipidemia is major problem among population those have sedentary life style as well as in diabetics. Bougainvillea spectabilis is most commonly found in India as an ornamental plant and has got anti-diabetic action due to presence of one insulin mimicking agent D-pinitol (3-O-methyl-chiroinositol. The present investigation was undertaken to evaluate the effect of alcoholic extract of leaves of Bougainvillea spectabilis (AEBSL on serum lipid profile in albino rats fed with high fat diet (HFD and to compare it with a standard hypolipidaemic drug simvastatin. Thirty healthy albino rats of both sexes (100-200 g were randomized into 5 groups of 6 animals each. The groups were treated as follows: Group A: normal diet (ND; Group B: HFD (vanaspati ghee + coconut oil mixture in ratio of 3:2 at 10 ml/kg/day; Group C: HFD+ AEBSL (100 mg/kg/day; Group D: HFD + AEBSL (200 mg/kg/day; Group E: HFD + simvastatin (1.8 mg/kg/day. Lipid profile was estimated after 8 weeks of treatment. AEBSL showed a significant (p<0.01 reduction in total cholesterol (TC, Triglyceride (TG, Low density lipoprotein (LDL, Very low density lipoprotein (VLDL levels and significant (p<0.01 increase in high density lipoproteins (HDL in hypercholesteromic rats (Group C and Group D. AEBSL 200 mg/kg/day found to be more effective than AEBSL 100 mg/kg/day. There is also significant improvement in atherogenic index (p<0.01 and increases the percentage of protection AEBSL treated animals. Alcoholic extract of leaves of Bougainvillea spectabilis leaves have excellent lipid lowering potentiality.

  17. Effects of puerarin on lipid accumulation and metabolism in high-fat diet-fed mice.

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    Guodong Zheng

    Full Text Available In order to investigate the mechanisms by which puerarin from kudzu root extract regulates lipid metabolism, fifty mice were randomly assigned to five groups: normal diet, high-fat diet (HFD, and HFD containing 0.2%, 0.4% or 0.8% puerarin for 12 weeks. Body weight, intraperitioneal adipose tissue (IPAT weight, serum biochemical parameters, and hepatic and feces lipids were measured. Activity and mRNA and protein expressions of hepatic lipid metabolism-related enzymes were analyzed. Compared with HFD, 0.4% and 0.8% puerarin significantly decreased body and IPAT weight. There was a significant decrease in the serum and hepatic concentrations of total cholesterol, triglycerides and leptin in mice fed the 0.4% and 0.8% puerarin diets compared with HFD. Fatty acid synthase activity was suppressed in mice fed the 0.4% and 0.8% puerarin diets, while the activities of AMP-activated protein kinase (AMPK, carnitine acyltransferase (CAT and hormone-sensitive lipase (HSL were increased. mRNA expression of peroxisome proliferator-activated receptor γ 2 (PPARγ 2 was down-regulated in liver of mice fed the 0.8% diet compared with HFD, while mRNA expression of CAT and HSL was considerably up-regulated by 0.4% and 0.8% puerarin diets. The protein expression of PPARγ2 in liver was decreased and those of p-AMPK, HSL and p-HSL were increased in mice fed 0.4% and 0.8% puerarin diets. These results suggest that > 0.4% puerarin influenced the activity, mRNA and protein levels of hepatic lipid metabolism-related enzymes, decreasing serum and liver lipids, body weight gain and fat accumulation. Puerarin might be beneficial to prevent lifestyle-related diseases.

  18. High-fat Diet Accelerates Intestinal Tumorigenesis Through Disrupting Intestinal Cell Membrane Integrity

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    Park, Mi-Young; Kim, Min Young; Seo, Young Rok; Kim, Jong-Sang; Sung, Mi-Kyung

    2016-01-01

    Background: Excess energy supply induces chronic low-grade inflammation in association with oxidative stress in various tissues including intestinal epithelium. The objective of this study was to investigate the effect of high-fat diet (HFD) on intestinal cell membrane integrity and intestinal tumorigenesis in ApcMin/+ mice. Methods: Mice were fed with either normal diet (ND) or HFD for 12 weeks. The number of intestinal tumors were counted and biomarkers of endotoxemia, oxidative stress, and inflammation were determined. Changes in intestinal integrity was measured by fluorescein isothiocyanate (FITC)-dextran penetration and membrane gap junction protein expression. Results: HFD group had significantly higher number of tumors compared to ND group (P < 0.05). Blood total antioxidant capacity was lower in HFD group, while colonic 8-hydroxy-2′-deoxyguanosine level, a marker of oxidative damage, was higher in HFD group compared to that of ND group (P < 0.05). The penetration of FITC-dextran was substantially increased in HFD group (P < 0.05) while the expressions of membrane gap junction proteins including zonula occludens-1, claudin-1, and occludin were lower in HFD group (P < 0.05) compared to those in ND group. Serum concentration of lipopolysaccharide (LPS) receptor (CD14) and colonic toll-like receptor 4 (a LPS receptor) mRNA expression were significantly higher in HFD group than in ND group (P < 0.05), suggesting that significant endotoxemia may occur in HFD group due to the increased membrane permeability. Serum interleukin-6 concentration and myeloperoxidase activity were also higher in HFD group compared to those of ND group (P < 0.05). Conclusions: HFD increases oxidative stress disrupting intestinal gap junction proteins, thereby accelerating membrane permeability endotoxemia, inflammation, and intestinal tumorigenesis. PMID:27390738

  19. High fat diet and GLP-1 drugs induce pancreatic injury in mice

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    Rouse, Rodney, E-mail: rodney.rouse@fda.hhs.gov; Xu, Lin; Stewart, Sharron; Zhang, Jun

    2014-04-15

    Glucagon Like Peptide-1 (GLP-1) drugs are currently used to treat type-2 diabetes. Safety concerns for increased risk of pancreatitis and pancreatic ductal metaplasia have accompanied these drugs. High fat diet (HFD) is a type-2 diabetes risk factor that may affect the response to GLP-1 drug treatment. The objective of the present study was to investigate the effects of diet and GLP-1 based drugs on the exocrine pancreas in mice. Experiments were designed in a mouse model of insulin resistance created by feeding a HFD or standard diet (STD) for 6 weeks. The GLP-1 drugs, sitagliptin (SIT) and exenatide (EXE) were administered once daily for additional 6 weeks in both mice fed HFD or STD. The results showed that body weight, blood glucose levels, and serum levels of pro-inflammatory cytokines (TNFα, IL-1β, and KC) were significantly greater in HFD mice than in STD mice regardless of GLP-1 drug treatment. The semi-quantitative grading showed that pancreatic changes were significantly greater in EXE and SIT-treated mice compared to control and that HFD exacerbated spontaneous exocrine pancreatic changes seen in saline-treated mice on a standard diet. Exocrine pancreatic changes identified in this study included acinar cell injury (hypertrophy, autophagy, apoptosis, necrosis, and atrophy), vascular injury, interstitial edema and inflammation, fat necrosis, and duct changes. These findings support HFD as a risk factor to increased susceptibility/severity for acute pancreatitis and indicate that GLP-1 drugs cause pancreatic injury that can be exacerbated in a HFD environment.

  20. High fat diet and GLP-1 drugs induce pancreatic injury in mice

    International Nuclear Information System (INIS)

    Glucagon Like Peptide-1 (GLP-1) drugs are currently used to treat type-2 diabetes. Safety concerns for increased risk of pancreatitis and pancreatic ductal metaplasia have accompanied these drugs. High fat diet (HFD) is a type-2 diabetes risk factor that may affect the response to GLP-1 drug treatment. The objective of the present study was to investigate the effects of diet and GLP-1 based drugs on the exocrine pancreas in mice. Experiments were designed in a mouse model of insulin resistance created by feeding a HFD or standard diet (STD) for 6 weeks. The GLP-1 drugs, sitagliptin (SIT) and exenatide (EXE) were administered once daily for additional 6 weeks in both mice fed HFD or STD. The results showed that body weight, blood glucose levels, and serum levels of pro-inflammatory cytokines (TNFα, IL-1β, and KC) were significantly greater in HFD mice than in STD mice regardless of GLP-1 drug treatment. The semi-quantitative grading showed that pancreatic changes were significantly greater in EXE and SIT-treated mice compared to control and that HFD exacerbated spontaneous exocrine pancreatic changes seen in saline-treated mice on a standard diet. Exocrine pancreatic changes identified in this study included acinar cell injury (hypertrophy, autophagy, apoptosis, necrosis, and atrophy), vascular injury, interstitial edema and inflammation, fat necrosis, and duct changes. These findings support HFD as a risk factor to increased susceptibility/severity for acute pancreatitis and indicate that GLP-1 drugs cause pancreatic injury that can be exacerbated in a HFD environment