Self-reinforcement and protein sustained delivery of hyaluronan hydrogel by tailoring a dually cross-linked network

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Luo, Chunhong; Xu, Guoguang; Wang, Xinghui; Tu, Mei; Zeng, Rong; Rong, Jianhua; Zhao, Jianhao

2015-01-01

A series of self-reinforcing hyaluronan hydrogels were developed to improve mechanical properties and protein sustained delivery thanks to a dually cross-linked network. Hyaluronan gel particles (HGPs, 1–5 μm in diameter) with different cross-linking densities, i.e. HGPs-1.5, HGPs-3 and HGPs-15, were prepared in an inverse emulsion system and used as the reinforcing phase after glycidyl methacrylation, while glycidyl methacrylated hyaluronan with a substitution degree of 45.2% was synthesized as the matrix phase. These two phases were cross-linked under ultraviolet irradiation to form self-reinforcing hyaluronan hydrogels (srHAs) that showed typical cross-linked structure of HGPs connecting the matrix phase by cross-section observation. In comparison to hyaluronan bulk gels and their blends with HGPs, srHAs distinctly enhanced the mechanical properties and BSA long-term sustained delivery, especially srHA-1.5 showed the highest compressive modulus of 220 ± 15 kPa and the slowest BSA delivery (67% release at 14 d). The 3T3 fibroblast cell culture showed that all the srHAs had no cytotoxicity. - Highlights: • New self-reinforcing HA hydrogels with a dually cross-linked network were developed. • Self-reinforcing HA hydrogels greatly enhanced the mechanical properties. • Self-reinforcing HA hydrogels prolonged the sustained delivery of BSA. • The self-reinforcing mechanism and BSA diffusion mechanism were discussed. • Self-reinforcing HA hydrogels had no cytotoxicity to 3T3 fibroblast cells

Hyaluronan microgel as a potential carrier for protein sustained delivery by tailoring the crosslink network

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Luo, Chunhong [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Zhao, Jianhao, E-mail: jhzhao@jnu.edu.cn [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China); Tu, Mei; Zeng, Rong; Rong, Jianhua [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China)

2014-03-01

Hyaluronan (HA) microgels with different crosslink network, i.e. HGPs-1, HGPs-1.5, HGPs-3, HGPs-6 and HGPs-15, were synthesized using divinyl sulfone (DVS) as the crosslinker in an inverse microemulsion system for controlling the sustained delivery of bovine serum albumin (BSA). With increasing the crosslinker content, the average particle size slightly increased from 1.9 ± 0.3 μm to 3.6 ± 0.5 μm by dynamic laser scattering analysis. However, the crosslinker content had no significant effect on the morphology of HA microgels by scanning and transmission electron microscopes. Fourier transform infrared spectroscopy and elemental analysis proved more sulfur participated in the crosslink reaction when raising the crosslinker amount. The water swelling test confirmed the increasing crosslink density with the crosslinker content by calculating the average molecular weight between two crosslink points to be 8.25 ± 2.51 × 10{sup 5}, 1.26 ± 0.43 × 10{sup 5}, 0.96 ± 0.09 × 10{sup 5}, 0.64 ± 0.03 × 10{sup 5}, and 0.11 ± 0.01 × 10{sup 5} respectively. The degradation of HA microgels by hyaluronidase slowed down by enhancing the crosslink density, only about 5% of HGPs-15 was degraded as opposed to over 90% for HGPs-1. BSA loading had no obvious influence on the surface morphology of HA microgels but seemed to induce their aggregation. The increase of crosslink density decreased the BSA loading capacity but facilitated its long-term sustained delivery. When the molar ratio of DVS to repeating unit of HA reached 3 or higher, similar delivery profiles were obtained. Among all these HA microgels, HGPs-3 was the optimal carrier for BSA sustained delivery in this system because it possessed both high BSA loading capacity and long-term delivery profile simultaneously. - Highlights: • HA microgels with different crosslink densities were prepared. • The crosslinker content had little effect on the morphology and size of HA microgels. • The crosslink density

Pathogenesis and Inhibition of Flaviviruses from a Carbohydrate Perspective

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So Young Kim

2017-05-01

Full Text Available Flaviviruses are enveloped, positive single stranded ribonucleic acid (RNA viruses with various routes of transmission. While the type and severity of symptoms caused by pathogenic flaviviruses vary from hemorrhagic fever to fetal abnormalities, their general mechanism of host cell entry is similar. All pathogenic flaviviruses, such as dengue virus, yellow fever virus, West Nile virus, Japanese encephalitis virus, and Zika virus, bind to glycosaminglycans (GAGs through the putative GAG binding sites within their envelope proteins to gain access to the surface of host cells. GAGs are long, linear, anionic polysaccharides with a repeating disaccharide unit and are involved in many biological processes, such as cellular signaling, cell adhesion, and pathogenesis. Flavivirus envelope proteins are N-glycosylated surface proteins, which interact with C-type lectins, dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN through their glycans. In this review, we discuss both host and viral surface receptors that have the carbohydrate components, focusing on the surface interactions in the early stage of flavivirus entry. GAG-flavivirus envelope protein interactions as well as interactions between flavivirus envelope proteins and DC-SIGN are discussed in detail. This review also examines natural and synthetic inhibitors of flaviviruses that are carbohydrate-based or carbohydrate-targeting. Both advantages and drawbacks of these inhibitors are explored, as are potential strategies to improve their efficacy to ultimately help eradicate flavivirus infections.

Hypothalamic pathogenesis of type 2 diabetes.

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Koshiyama, Hiroyuki; Hamamoto, Yoshiyuki; Honjo, Sachiko; Wada, Yoshiharu; Lkeda, Hiroki

2006-01-01

There have recently been increasing experimental and clinical evidences suggesting that hypothalamic dysregulation may be one of the underlying mechanisms of abnormal glucose metabolism. First, increased hypothalamic-pituitary-adrenal axis activity induced by uncontrollable excess stress may cause diabetes mellitus as well as dyslipidemia, visceral obesity, and osteoporosis with some resemblance to Cushing's disease. Second, several molecules are known to be expressed both in pancreas and hypothalamus; adenosine triphosphate-sensitive potassium channels, malonyl-CoA, glucokinase, and AMP-activated protein kinase. Those molecules appear to form an integrated hypothalamic system, which may sense hypothalamic fuel status, especially glucose level, and inhibit action of insulin on hepatic gluconeogenesis, thereby forming a brain-liver circuit. Third, hypothalamic resistance to insulin as an adiposity signal may be involved in pathogenesis of peripheral insulin resistance. The results with mice with a neuron-specific disruption of the insulin receptor gene or those lacking insulin receptor substrate 2 in hypothalamus supported this possibility. Finally, it has very recently been suggested that dysregulation of clock genes in hypothalamus may cause abnormal glucose metabolism. Taken together, it is plausible that some hypothalamic abnormality may underlie at least some portion of type 2 diabetes or insulin resistance in humans, and this viewpoint of hypothalamic pathogenesis of type 2 diabetes may lead to the development of new drugs for type 2 diabetes.

Expression of progerin in aging mouse brains reveals structural nuclear abnormalities without detectible significant alterations in gene expression, hippocampal stem cells or behavior

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Baek, Jean-Ha; Schmidt, Eva; Viceconte, Nikenza

2015-01-01

, the HGPS mutation results in organ-specific defects. For example, bone and skin are strongly affected by HGPS, while the brain appears to be unaffected. There are no definite explanations as to the variable sensitivity to progeria disease among different organs. In addition, low levels of progerin have...

Astrovirus Pathogenesis

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Cydney Johnson

2017-01-01

Full Text Available Astroviruses are a major cause of diarrhea in the young, elderly, and the immunocompromised. Since the discovery of human astrovirus type 1 (HAstV-1 in 1975, the family Astroviridae has expanded to include two more human clades and numerous mammalian and avian-specific genotypes. Despite this, there is still little known about pathogenesis. The following review highlights the current knowledge of astrovirus pathogenesis, and outlines the critical steps needed to further astrovirus research, including the development of animal models of cell culture systems.

Unique Preservation of Neural Cells in Hutchinson- Gilford Progeria Syndrome Is Due to the Expression of the Neural-Specific miR-9 MicroRNA

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Xavier Nissan

2012-07-01

Full Text Available One puzzling observation in patients affected with Hutchinson-Gilford progeria syndrome (HGPS, who overall exhibit systemic and dramatic premature aging, is the absence of any conspicuous cognitive impairment. Recent studies based on induced pluripotent stem cells derived from HGPS patient cells have revealed a lack of expression in neural derivatives of lamin A, a major isoform of LMNA that is initially produced as a precursor called prelamin A. In HGPS, defective maturation of a mutated prelamin A induces the accumulation of toxic progerin in patient cells. Here, we show that a microRNA, miR-9, negatively controls lamin A and progerin expression in neural cells. This may bear major functional correlates, as alleviation of nuclear blebbing is observed in nonneural cells after miR-9 overexpression. Our results support the hypothesis, recently proposed from analyses in mice, that protection of neural cells from progerin accumulation in HGPS is due to the physiologically restricted expression of miR-9 to that cell lineage.

Osteoblast role in osteoarthritis pathogenesis.

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Maruotti, Nicola; Corrado, Addolorata; Cantatore, Francesco P

2017-11-01

Even if osteoarthritis pathogenesis is still poorly understood, numerous evidences suggest that osteoblasts dysregulation plays a key role in osteoarthritis pathogenesis. An abnormal expression of OPG and RANKL has been described in osteoarthritis osteoblasts, which is responsible for abnormal bone remodeling and decreased mineralization. Alterations in genes expression are involved in dysregulation of osteoblast function, bone remodeling, and mineralization, leading to osteoarthritis development. Moreover, osteoblasts produce numerous transcription factors, growth factors, and other proteic molecules which are involved in osteoarthritis pathogenesis. © 2017 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc.

Gastric Polyp Growth during Endoscopic Surveillance for Esophageal Varices or Barrett's Esophagus.

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Livovsky, Dan M; Pappo, Orit; Skarzhinsky, Galina; Peretz, Asaf; Turvall, Elliot; Ackerman, Zvi

2016-05-01

We recently observed patients with chronic liver disease (CLD) or chronic reflux symptoms (CRS) who developed gastric polyps (GPs) while undergoing surveillance gastroscopies for the detection of esophageal varices or Barrett's esophagus, respectively. To identify risk factors for GP growth and estimate its growth rate. GP growth rate was defined as the number of days since the first gastroscopy (without polyps) in the surveillance program, until the gastroscopy when a GP was discovered. Gastric polyp growth rates in CLD and CRS patients were similar. However, hyperplastic gastric polyps (HGPs) were detected more often (87.5% vs. 60.5%, P = 0.051) and at a higher number (2.57 ± 1.33 vs. 1.65 ± 0.93, P = 0.021) in the CLD patients. Subgroup analysis revealed the following findings only in CLD patients with HGPs: (i) a positive correlation between the GP growth rate and the patient's age; the older the patient, the higher the GP growth rate (r = 0.7, P = 0.004). (ii) A negative correlation between the patient's age and the Ki-67 proliferation index value; the older the patient, the lower the Ki-67 value (r = -0.64, P = 0.02). No correlation was detected between Ki-67 values of HGPs in CLD patients and the presence of portal hypertension, infection with Helicobacter pylori, or proton pump inhibitor use. In comparison with CRS patients, CLD patients developed HGPs more often and at a greater number. Young CLD patients may have a tendency to develop HGPs at a faster rate than elderly CLD patients.

Hyaluronic acid based hydrogel system for soft tissue regeneration and drug delivery

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Jha, Amit Kumar

We have developed hyaluronic acid (HA)-based, biomimetic hydrogel matrices that are hierarchically structured, mechanically robust and biologically active. Specifically, HA-based hydrogel particles (HGPs) with controlled sizes, defined porosity, and improved stability were synthesized using different inverse emulsion systems and crosslinking chemistries. The resultant particles either contained residual functional groups or were rendered reactive by subsequent chemical modifications. HA-based doubly crosslinked networks (DXNs) were synthesized via covalent crosslinking of HA HGPs with soluble HA macromers carrying mutually reactive functional groups. These hybrid matrices are hierarchical in nature, consisting of densely crosslinked HGPs integrated in a loosely connected secondary matrix. Their mechanical properties and degradation kinetics can be readily tuned by varying the particle size, functional group density, intra- and interparticle crosslinking. To improve the biological functions of HA HGPs, perlecan domain I (PlnDI), a basement membrane proteoglycan that has strong affinity for various heparin binding growth factors (HBGFs), was successfully conjugated to the particles through the core protein via a flexible poly(ethylene glycol) (PEG) linker. The immobilized PlnDI maintains its ability to bind bone morphogenetic proteins (BMP-2) and modulates its in vitro release. A similar, sustained release of BMP-2 was achieved by encapsulating BMP-2-loaded HGPs within a photocrosslinked HA matrix. When encapsulated in HA DXNs, primary bovine chondrocytes were able to maintain their phenotype, proliferate readily and produce abundant glycosaminoglycan. Finally, cell-adhesive HA DXNs were fabricated by encapsulating gelatin-decorated HA HGPs in a secondary HA matrix. Human MSCs were shown to adhere to the composite matrix through the focal adhesion sites clustered on particle surface. The cell-adhesive composite matrices supported hMSC proliferation and migration into

Autoantibodies against complement components in systemic lupus erythematosus - role in the pathogenesis and clinical manifestations.

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Hristova, M H; Stoyanova, V S

2017-12-01

Many complement structures and a number of additional factors, i.e. autoantibodies, receptors, hormones and cytokines, are implicated in the complex pathogenesis of systemic lupus erythematosus. Genetic defects in the complement as well as functional deficiency due to antibodies against its components lead to different pathological conditions, usually clinically presented. Among them hypocomplementemic urticarial vasculitis, different types of glomerulonephritis as dense deposit disease, IgA nephropathy, atypical haemolytic uremic syndrome and lupus nephritis are very common. These antibodies cause conformational changes leading to pathological activation or inhibition of complement with organ damage and/or limited capacity of the immune system to clear immune complexes and apoptotic debris. Finally, we summarize the role of complement antibodies in the pathogenesis of systemic lupus erythematosus and discuss the mechanism of some related clinical conditions such as infections, thyroiditis, thrombosis, acquired von Willebrand disease, etc.

Satisfaction of health professionals after implementation of a primary care hospital emergency centre in Switzerland: A prospective before-after study.

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Hess, Sascha; Sidler, Patrick; Chmiel, Corinne; Bögli, Karin; Senn, Oliver; Eichler, Klaus

2015-10-01

The increasing number of patients requiring emergency care is a challenge and leads to decreased satisfaction of health professionals at emergency departments (EDs). Thus, a Swiss hospital implemented a hospital-associated primary care centre at the ED. The study aim was to investigate changes in job satisfaction of ED staff before and after the implementation of this new service model and to measure hospital GPs' (HGPs) satisfaction at the hospital-associated primary care centre. This study was embedded in a large prospective before-after study over two years. We examined changes in job satisfaction with a questionnaire followed by selected interviews approaching all of the involved 25 ED staff members and 38 HGPs. The new emergency care model increased job satisfaction of ED staff and HGPs in all measured dimensions. The overall job satisfaction of ED employees improved from 76.5 to 83.9 points (visual analogue scale 0-100; difference 7.4 points [95% CI: 1.3 to 13.5, p = 0.02]). 86% of 29 HGPs preferred to provide their out-of-hours service at the new hospital-associated primary care centre. The hospital-associated primary care centre is a promising option to improve job satisfaction of different health professionals in emergency care. Copyright © 2015 Elsevier Ltd. All rights reserved.

Exosomes in Human Immunodeficiency Virus Type I Pathogenesis: Threat or Opportunity?

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Sin-Yeang Teow

2016-01-01

Full Text Available Nanometre-sized vesicles, also known as exosomes, are derived from endosomes of diverse cell types and present in multiple biological fluids. Depending on their cellular origins, the membrane-bound exosomes packed a variety of functional proteins and RNA species. These microvesicles are secreted into the extracellular space to facilitate intercellular communication. Collective findings demonstrated that exosomes from HIV-infected subjects share many commonalities with Human Immunodeficiency Virus Type I (HIV-1 particles in terms of proteomics and lipid profiles. These observations postulated that HIV-resembled exosomes may contribute to HIV pathogenesis. Interestingly, recent reports illustrated that exosomes from body fluids could inhibit HIV infection, which then bring up a new paradigm for HIV/AIDS therapy. Accumulative findings suggested that the cellular origin of exosomes may define their effects towards HIV-1. This review summarizes the two distinctive roles of exosomes in regulating HIV pathogenesis. We also highlighted several additional factors that govern the exosomal functions. Deeper understanding on how exosomes promote or abate HIV infection can significantly contribute to the development of new and potent antiviral therapeutic strategy and vaccine designs.

The C protein of measles virus inhibits the type I interferon response

International Nuclear Information System (INIS)

Shaffer, Jessica A.; Bellini, William J.; Rota, Paul A.

2003-01-01

Type I interferons (IFNα/β) are an important part of innate immunity to viral infections because they induce an antiviral response and limit viral replication until the adaptive response clears the infection. Since the nonstructural proteins of several paramyxoviruses inhibit the IFNα/β response, we chose to explore the role of the C protein of measles virus (MV) in such inhibition. Previous studies have suggested that the MV C protein may serve as a virulence factor, but its role in the pathogenesis of MV remains undefined. In the present study, a recombinant MV strain that does not express the C protein (MV C-) and its parental strain (Ed Tag) were used. Growth of MV C- was restricted in human peripheral blood mononuclear cells and HeLa cells, but in the presence of neutralizing antibodies to IFNα/β, MV C- produced titers that were equivalent to those of Ed Tag. In addition, expression of the MV C protein from plasmid DNA inhibited the production of an IFNα/β responsive reporter gene and, to a lesser extent, inhibited an IFNγ responsive reporter gene. The ability of the MV C protein to suppress the IFNα/β response was confirmed using a biologic assay. After IFNβ stimulation, HeLa cells infected with Ed Tag produced five-fold less IFNα/β than cells infected with MV C-. While the mechanism of inhibition remains unclear, these data suggest that the MV C protein plays an important role in the pathogenesis of MV by inhibiting IFNα/β signaling

Functional analysis of miR-181a and Fas involved in hepatitis B virus-related hepatocellular carcinoma pathogenesis

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Zou, Chengcheng; Chen, Juan; Chen, Ke; Wang, Sen; Cao, Yiyi; Zhang, Jinnan; Sheng, Yanrui; Huang, Ailong; Tang, Hua

2015-01-01

The hepatitis B virus (HBV) is responsible for most of hepatocellular carcinoma (HCC). However, whether HBV plays an important role during hepatocarcinogenesis through effecting miRNAs remains unknown. Here, we reported that HBV up-regulated microRNA-181a (miR-181a) by enhancing its promoter activity. Simultaneously, we found that miR-181a inhibited apoptosis in vitro and promoted tumor cell growth in vivo. TNF receptor superfamily member 6 (Fas) was further identified as a target of miR-181a. We also found that Fas could reverse the apoptosis-inhibition effect induced by miR-181a. Moreover, HBV could inhibit cell apoptosis by down-regulating Fas expression, which could be reversed by miR-181a inhibitor. Our data demonstrated that HBV suppressed apoptosis of hepatoma cells by up-regulating miR-181a expression and down-regulating Fas expression, which may provide a new understanding of the mechanism in HBV-related HCC pathogenesis. - Highlights: • HBV could up-regulate miR-181a expression by interacting with nt−800 to +240 in its promoter region in HCC cell lines. • HBV could down-regulate Fas expression and suppress apoptosis of hepatoma cells, which could be reversed by miR-181a inhibitor. • Up-regulation of miR-181a promoted proliferation of hepatoma cells and repressed apoptosis, which could be reversed by Fas. • Our study provides a new understanding of the mechanism in HBV-related HCC pathogenesis

Functional analysis of miR-181a and Fas involved in hepatitis B virus-related hepatocellular carcinoma pathogenesis

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Zou, Chengcheng; Chen, Juan; Chen, Ke; Wang, Sen; Cao, Yiyi; Zhang, Jinnan; Sheng, Yanrui; Huang, Ailong; Tang, Hua, E-mail: tanghua86162003@aliyun.com

2015-02-15

The hepatitis B virus (HBV) is responsible for most of hepatocellular carcinoma (HCC). However, whether HBV plays an important role during hepatocarcinogenesis through effecting miRNAs remains unknown. Here, we reported that HBV up-regulated microRNA-181a (miR-181a) by enhancing its promoter activity. Simultaneously, we found that miR-181a inhibited apoptosis in vitro and promoted tumor cell growth in vivo. TNF receptor superfamily member 6 (Fas) was further identified as a target of miR-181a. We also found that Fas could reverse the apoptosis-inhibition effect induced by miR-181a. Moreover, HBV could inhibit cell apoptosis by down-regulating Fas expression, which could be reversed by miR-181a inhibitor. Our data demonstrated that HBV suppressed apoptosis of hepatoma cells by up-regulating miR-181a expression and down-regulating Fas expression, which may provide a new understanding of the mechanism in HBV-related HCC pathogenesis. - Highlights: • HBV could up-regulate miR-181a expression by interacting with nt−800 to +240 in its promoter region in HCC cell lines. • HBV could down-regulate Fas expression and suppress apoptosis of hepatoma cells, which could be reversed by miR-181a inhibitor. • Up-regulation of miR-181a promoted proliferation of hepatoma cells and repressed apoptosis, which could be reversed by Fas. • Our study provides a new understanding of the mechanism in HBV-related HCC pathogenesis.

Chemical screening identifies ROCK as a target for recovering mitochondrial function in Hutchinson-Gilford progeria syndrome.

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Kang, Hyun Tae; Park, Joon Tae; Choi, Kobong; Choi, Hyo Jei Claudia; Jung, Chul Won; Kim, Gyu Ree; Lee, Young-Sam; Park, Sang Chul

2017-06-01

Hutchinson-Gilford progeria syndrome (HGPS) constitutes a genetic disease wherein an aging phenotype manifests in childhood. Recent studies indicate that reactive oxygen species (ROS) play important roles in HGPS phenotype progression. Thus, pharmacological reduction in ROS levels has been proposed as a potentially effective treatment for patient with this disorder. In this study, we performed high-throughput screening to find compounds that could reduce ROS levels in HGPS fibroblasts and identified rho-associated protein kinase (ROCK) inhibitor (Y-27632) as an effective agent. To elucidate the underlying mechanism of ROCK in regulating ROS levels, we performed a yeast two-hybrid screen and discovered that ROCK1 interacts with Rac1b. ROCK activation phosphorylated Rac1b at Ser71 and increased ROS levels by facilitating the interaction between Rac1b and cytochrome c. Conversely, ROCK inactivation with Y-27632 abolished their interaction, concomitant with ROS reduction. Additionally, ROCK activation resulted in mitochondrial dysfunction, whereas ROCK inactivation with Y-27632 induced the recovery of mitochondrial function. Furthermore, a reduction in the frequency of abnormal nuclear morphology and DNA double-strand breaks was observed along with decreased ROS levels. Thus, our study reveals a novel mechanism through which alleviation of the HGPS phenotype is mediated by the recovery of mitochondrial function upon ROCK inactivation. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Pathogenesis of motor neuron disease

Institute of Scientific and Technical Information of China (English)

Xuefei Wang

2006-01-01

OBJECTIVE: To summarize and analyze the factors and theories related to the attack of motor neuron disease, and comprehensively investigate the pathogenesis of motor neuron disease.DATA SOURCES: A search of Pubmed database was undertaken to identify articles about motor neuron disease published in English from January 1994 to June 2006 by using the keywords of "neurodegenerative diseases". Other literatures were collected by retrieving specific journals and articles.STUDY SELECTION: The data were checked primarily, articles related to the pathogenesis of motor neuron disease were involved, and those obviously irrelated to the articles were excluded.DATA EXTRACTION: Totally 54 articles were collected, 30 of them were involved, and the other 24 were excluded.DATA SYNTHESIS: The pathogenesis of motor neuron disease has multiple factors, and the present related theories included free radical oxidation, excitotoxicity, genetic and immune factors, lack of neurotrophic factor,injury of neurofilament, etc. The studies mainly come from transgenic animal models, cell culture in vitro and patients with familial motor neuron disease, but there are still many restrictions and disadvantages.CONCLUSION: It is necessary to try to find whether there is internal association among different mechanisms,comprehensively investigate the pathogenesis of motor neuron diseases, in order to provide reliable evidence for the clinical treatment.

Purification and characterization of pathogenesis-related antifungal beta 1,3 glucanase from basrai banana fruit

International Nuclear Information System (INIS)

Yasmin, N.; Saleem, M.; Chaudhry, Z.I.

2012-01-01

Pathogenesis-related proteins have been described as proteins that are encoded by the plant genome and that are induced specifically in response to infections by pathogens. These represent a collection of unrelated protein families which function as part of the plant defense system. Pathogenesis-related antifungal protein has been isolated from the pulp of ripe Basrai bananas and purified through ammonium sulphate precipitation, Sephadex G- 75 gel filtration chromatography and electro-elution. The purified protein with acidic character (pI 6.81). has molecular weight of 34.5kDa, as determined by MALOI- TOF mass spectrometry. Mascot score obtained was 473 greater than 82, indicate extensive homology at a significant level (p.0.05) and the protein was identified as beta 1,3-glucanase with antifungal activity. It inhibited the growth of Fusarium oxysporum demonstrating the potential role of Basrai banana antifungal protein to control fungal diseases in plants, animals and human. (author)

Arecoline inhibits endothelial cell growth and migration and the attachment to mononuclear cells

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Shuei-Kuen Tseng

2014-09-01

Conclusion: Arecoline impaired vascular endothelial cells by inhibiting their growth and migration and their adhesion to U937 mononuclear cells. These results reveal that arecoline may contribute to the pathogenesis of oral submucous fibrosis and cardiovascular diseases by affecting endothelial cell function in BQ chewers.

The Role of Extracellular Histones in Influenza Virus Pathogenesis.

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Ashar, Harshini K; Mueller, Nathan C; Rudd, Jennifer M; Snider, Timothy A; Achanta, Mallika; Prasanthi, Maram; Pulavendran, Sivasami; Thomas, Paul G; Ramachandran, Akhilesh; Malayer, Jerry R; Ritchey, Jerry W; Rajasekhar, Rachakatla; Chow, Vincent T K; Esmon, Charles T; Teluguakula, Narasaraju

2018-01-01

Although exaggerated host immune responses have been implicated in influenza-induced lung pathogenesis, the etiologic factors that contribute to these events are not completely understood. We previously demonstrated that neutrophil extracellular traps exacerbate pulmonary injury during influenza pneumonia. Histones are the major protein components of neutrophil extracellular traps and are known to have cytotoxic effects. Here, we examined the role of extracellular histones in lung pathogenesis during influenza. Mice infected with influenza virus displayed high accumulation of extracellular histones, with widespread pulmonary microvascular thrombosis. Occluded pulmonary blood vessels with vascular thrombi often exhibited endothelial necrosis surrounded by hemorrhagic effusions and pulmonary edema. Histones released during influenza induced cytotoxicity and showed strong binding to platelets within thrombi in infected mouse lungs. Nasal wash samples from influenza-infected patients also showed increased accumulation of extracellular histones, suggesting a possible clinical relevance of elevated histones in pulmonary injury. Although histones inhibited influenza growth in vitro, in vivo treatment with histones did not yield antiviral effects and instead exacerbated lung pathology. Blocking with antihistone antibodies caused a marked decrease in lung pathology in lethal influenza-challenged mice and improved protection when administered in combination with the antiviral agent oseltamivir. These findings support the pathogenic effects of extracellular histones in that pulmonary injury during influenza was exacerbated. Targeting histones provides a novel therapeutic approach to influenza pneumonia. Copyright © 2018 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Tumor necrosis factor-alpha inhibits insulin's stimulating effect on glucose uptake and endothelium-dependent vasodilation in humans

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Rask-Madsen, Christian; Domínguez, Helena; Ihlemann, Nikolaj

2003-01-01

BACKGROUND: Inflammatory mechanisms could be involved in the pathogenesis of both insulin resistance and atherosclerosis. Therefore, we aimed at examining whether the proinflammatory cytokine tumor necrosis factor (TNF)-alpha inhibits insulin-stimulated glucose uptake and insulin....../or TNF-alpha were coinfused. During infusion of insulin alone for 20 minutes, forearm glucose uptake increased by 220+/-44%. This increase was completely inhibited during coinfusion of TNF-alpha (started 10 min before insulin) with a more pronounced inhibition of glucose extraction than of blood flow....... Furthermore, TNF-alpha inhibited the ACh forearm blood flow response (Palpha...

Pathogenesis of Hepatic Encephalopathy

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Irena Ciećko-Michalska

2012-01-01

Full Text Available Hepatic encephalopathy can be a serious complication of acute liver failure and chronic liver diseases, predominantly liver cirrhosis. Hyperammonemia plays the most important role in the pathogenesis of hepatic encephalopathy. The brain-blood barrier disturbances, changes in neurotransmission, neuroinflammation, oxidative stress, GABA-ergic or benzodiazepine pathway abnormalities, manganese neurotoxicity, brain energetic disturbances, and brain blood flow abnormalities are considered to be involved in the development of hepatic encephalopathy. The influence of small intestine bacterial overgrowth (SIBO on the induction of minimal hepatic encephalopathy is recently emphasized. The aim of this paper is to present the current views on the pathogenesis of hepatic encephalopathy.

Pathogenesis of Hepatic Encephalopathy

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Ciećko-Michalska, Irena; Szczepanek, Małgorzata; Słowik, Agnieszka; Mach, Tomasz

2012-01-01

Hepatic encephalopathy can be a serious complication of acute liver failure and chronic liver diseases, predominantly liver cirrhosis. Hyperammonemia plays the most important role in the pathogenesis of hepatic encephalopathy. The brain-blood barrier disturbances, changes in neurotransmission, neuroinflammation, oxidative stress, GABA-ergic or benzodiazepine pathway abnormalities, manganese neurotoxicity, brain energetic disturbances, and brain blood flow abnormalities are considered to be involved in the development of hepatic encephalopathy. The influence of small intestine bacterial overgrowth (SIBO) on the induction of minimal hepatic encephalopathy is recently emphasized. The aim of this paper is to present the current views on the pathogenesis of hepatic encephalopathy. PMID:23316223

Some aspects of periodontitis pathogenesis in children

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Shcherbina I.N.

2013-12-01

Full Text Available Inflammatory processes in the tissues surrounding tooth root are frequent enough and develop as the direct complication of caries. As acute periodontitis is manifested with grinding toothache and violation of ph¬y¬sio¬logical act of chewing, symptoms of general intoxication, the continuous sluggish chronic periodontitis is harmful and dangerous to the organism as well. It forms the state of chronic оdontogenetic intoxication and chroneosepsis with wrong functioning of some internal organs and body systems. The like complications can cause significant disturbance to the function of kidneys, liver, heart, joints and their treatment without ablating focus of inflammation is often in- effective; this must be taken into account by doctors-interns. However, scanning of the oral cavity by conservative means has its difficulties mostly because of ignoring pathogenesis of such inflammation. That is why activity of ferments of blood dehydrogenases from the periapical tissues of the teeth affected with the chronic periodontitis was studied. The level of succinate dehydrogenase and alpha-glycerophosphate degydrogenase of lymphocytes of 110 schoolchildren aged 13-17 years old was studied. The main group of examined individuals included those of infected with tuber¬culousis – 50 individuals, and the control group (60 individuals – clinically healthy ones without tuberculousis desease. All schoolchildren had 1 or 2 teeth affected with chronic periodontitis of the apical localization. The researchers found that a significant inhibition of activity of succinate dehydrogenase and alpha-glycerophosphate degydrogenase ferments occurs in the inflammatory periodontal tissues, which indicates to local immunity decline, and as a consequence, pathogenic bacteria activation. In people infected with tuberculousis these violations were more developed. Such features of periodontitis pathogenesis must be taken into account when providing a combined treatment.

Immunological pathogenesis of inflammatory bowel disease

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Seung Hoon Lee

2018-01-01

Full Text Available Inflammatory bowel disease (IBD is a chronic inflammatory state of the gastrointestinal tract and can be classified into 2 main clinical phenomena: Crohn's disease (CD and ulcerative colitis (UC. The pathogenesis of IBD, including CD and UC, involves the presence of pathogenic factors such as abnormal gut microbiota, immune response dysregulation, environmental changes, and gene variants. Although many investigations have tried to identify novel pathogenic factors associated with IBD that are related to environmental, genetic, microbial, and immune response factors, a full understanding of IBD pathogenesis is unclear. Thus, IBD treatment is far from optimal, and patient outcomes can be unsatisfactory. As result of massive studying on IBD, T helper 17 (Th17 cells and innate lymphoid cells (ILCs are investigated on their effects on IBD. A recent study of the plasticity of Th17 cells focused primarily on colitis. ILCs also emerging as novel cell family, which play a role in the pathogenesis of IBD. IBD immunopathogenesis is key to understanding the causes of IBD and can lead to the development of IBD therapies. The aim of this review is to explain the pathogenesis of IBD, with a focus on immunological factors and therapies.

Progerin sequestration of PCNA promotes replication fork collapse and mislocalization of XPA in laminopathy-related progeroid syndromes.

Science.gov (United States)

Hilton, Benjamin A; Liu, Ji; Cartwright, Brian M; Liu, Yiyong; Breitman, Maya; Wang, Youjie; Jones, Rowdy; Tang, Hui; Rusinol, Antonio; Musich, Phillip R; Zou, Yue

2017-09-01

Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disorder that is caused by a point mutation in the LMNA gene, resulting in production of a truncated farnesylated-prelamin A protein (progerin). We previously reported that XPA mislocalized to the progerin-induced DNA double-strand break (DSB) sites, blocking DSB repair, which led to DSB accumulation, DNA damage responses, and early replication arrest in HGPS. In this study, the XPA mislocalization to DSBs occurred at stalled or collapsed replication forks, concurrent with a significant loss of PCNA at the forks, whereas PCNA efficiently bound to progerin. This PCNA sequestration likely exposed ds-ssDNA junctions at replication forks for XPA binding. Depletion of XPA or progerin each significantly restored PCNA at replication forks. Our results suggest that although PCNA is much more competitive than XPA in binding replication forks, PCNA sequestration by progerin may shift the equilibrium to favor XPA binding. Furthermore, we demonstrated that progerin-induced apoptosis could be rescued by XPA, suggesting that XPA-replication fork binding may prevent apoptosis in HGPS cells. Our results propose a mechanism for progerin-induced genome instability and accelerated replicative senescence in HGPS.-Hilton, B. A., Liu, J., Cartwright, B. M., Liu, Y., Breitman, M., Wang, Y., Jones, R., Tang, H., Rusinol, A., Musich, P. R., Zou, Y. Progerin sequestration of PCNA promotes replication fork collapse and mislocalization of XPA in laminopathy-related progeroid syndromes. © FASEB.

Genes contributing to prion pathogenesis

DEFF Research Database (Denmark)

Tamgüney, Gültekin; Giles, Kurt; Glidden, David V

2008-01-01

incubation times, indicating that the conversion reaction may be influenced by other gene products. To identify genes that contribute to prion pathogenesis, we analysed incubation times of prions in mice in which the gene product was inactivated, knocked out or overexpressed. We tested 20 candidate genes...... show that many genes previously implicated in prion replication have no discernible effect on the pathogenesis of prion disease. While most genes tested did not significantly affect survival times, ablation of the amyloid beta (A4) precursor protein (App) or interleukin-1 receptor, type I (Il1r1...

Trichomonas vaginalis Pathogenesis: a Narrative Review

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Zahra Arab-Mazar

2015-07-01

Full Text Available In the latest articles which were published during 2013-2014, Trichomonas vaginalis (T. vaginalis was mentioned as a neglected sexual transmission disease (STD, while the exact mechanism of its pathogenesis has not been cleared yet. Although trichomonasiasis is easy curable, there is concern that resistance to drug are increasing. This common infection as concerning the important public health implications needs more research to be done for understanding the diagnosis, treatment, immunology and pathogenesis. In this review we searched all valuable and relevant information considering the pathogenesis of T. vaginalis. We referred to the information databases of Medline, PubMed, Scopus and Google scholar. The used keywords were the combinations of T. vaginalis and words associated with pathogenicity. This review discusses the host-parasite interaction and pathogenicity of this parasite.

Pathogenesis of ovarian cancer: current perspectives | Chesang ...

African Journals Online (AJOL)

Objective: To present a review of current knowledge of the pathogenesis of ovarian cancer and its clinical implications. Data Source: Extensive literature search was conducted to identify relevant studies. Study Selection: Studies in the English language about or related to pathogenesis of ovarian cancer were selected.

Inhibition of aldose reductase prevents experimental allergic airway inflammation in mice.

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Umesh C S Yadav

2009-08-01

Full Text Available The bronchial asthma, a clinical complication of persistent inflammation of the airway and subsequent airway hyper-responsiveness, is a leading cause of morbidity and mortality in critically ill patients. Several studies have shown that oxidative stress plays a key role in initiation as well as amplification of inflammation in airways. However, still there are no good anti-oxidant strategies available for therapeutic intervention in asthma pathogenesis. Most recent studies suggest that polyol pathway enzyme, aldose reductase (AR, contributes to the pathogenesis of oxidative stress-induced inflammation by affecting the NF-kappaB-dependent expression of cytokines and chemokines and therefore inhibitors of AR could be anti-inflammatory. Since inhibitors of AR have already gone through phase-III clinical studies for diabetic complications and found to be safe, our hypothesis is that AR inhibitors could be novel therapeutic drugs for the prevention and treatment of asthma. Hence, we investigated the efficacy of AR inhibition in the prevention of allergic responses to a common natural airborne allergen, ragweed pollen that leads to airway inflammation and hyper-responsiveness in a murine model of asthma.Primary Human Small Airway Epithelial Cells (SAEC were used to investigate the in vitro effects of AR inhibition on ragweed pollen extract (RWE-induced cytotoxic and inflammatory signals. Our results indicate that inhibition of AR prevents RWE -induced apoptotic cell death as measured by annexin-v staining, increase in the activation of NF-kappaB and expression of inflammatory markers such as inducible nitric oxide synthase (iNOS, cycloxygenase (COX-2, Prostaglandin (PG E(2, IL-6 and IL-8. Further, BALB/c mice were sensitized with endotoxin-free RWE in the absence and presence of AR inhibitor and followed by evaluation of perivascular and peribronchial inflammation, mucin production, eosinophils infiltration and airway hyperresponsiveness. Our results

Aetio-pathogenesis of breast cancer | Abdulkareem | Nigerian ...

African Journals Online (AJOL)

This is a literature review on the aetiology and pathogenesis of breast cancer, which is the most common cancer worldwide, and the second leading cause of cancer death, especially in Western countries. Several aetiological factors have been implicated in its pathogenesis, and include age, genetics, family history, diet, ...

Pathogenesis and immunobiology of brucellosis: review of Brucella-host interactions.

Science.gov (United States)

de Figueiredo, Paul; Ficht, Thomas A; Rice-Ficht, Allison; Rossetti, Carlos A; Adams, L Garry

2015-06-01

This review of Brucella-host interactions and immunobiology discusses recent discoveries as the basis for pathogenesis-informed rationales to prevent or treat brucellosis. Brucella spp., as animal pathogens, cause human brucellosis, a zoonosis that results in worldwide economic losses, human morbidity, and poverty. Although Brucella spp. infect humans as an incidental host, 500,000 new human infections occur annually, and no patient-friendly treatments or approved human vaccines are reported. Brucellae display strong tissue tropism for lymphoreticular and reproductive systems with an intracellular lifestyle that limits exposure to innate and adaptive immune responses, sequesters the organism from the effects of antibiotics, and drives clinical disease manifestations and pathology. Stealthy brucellae exploit strategies to establish infection, including i) evasion of intracellular destruction by restricting fusion of type IV secretion system-dependent Brucella-containing vacuoles with lysosomal compartments, ii) inhibition of apoptosis of infected mononuclear cells, and iii) prevention of dendritic cell maturation, antigen presentation, and activation of naive T cells, pathogenesis lessons that may be informative for other intracellular pathogens. Data sets of next-generation sequences of Brucella and host time-series global expression fused with proteomics and metabolomics data from in vitro and in vivo experiments now inform interactive cellular pathways and gene regulatory networks enabling full-scale systems biology analysis. The newly identified effector proteins of Brucella may represent targets for improved, safer brucellosis vaccines and therapeutics. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Viral pathogenesis in diagrams

National Research Council Canada - National Science Library

Tremblay, Michel; Berthiaume, Laurent; Ackermann, Hans-Wolfgang

2001-01-01

.... The 268 diagrams in Viral Pathogenesis in Diagrams were selected from over 800 diagrams of English and French virological literature, including one derived from a famous drawing by Leonardo da Vinci...

Dermal fibroblasts in Hutchinson-Gilford progeria syndrome with the lamin A G608G mutation have dysmorphic nuclei and are hypersensitive to heat stress

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Worman Howard J

2005-06-01

Full Text Available Abstract Background Hutchinson-Gilford progeria syndrome (HGPS, OMIM 176670 is a rare sporadic disorder with an incidence of approximately 1 per 8 million live births. The phenotypic appearance consists of short stature, sculptured nose, alopecia, prominent scalp veins, small face, loss of subcutaneous fat, faint mid-facial cyanosis, and dystrophic nails. HGPS is caused by mutations in LMNA, the gene that encodes nuclear lamins A and C. The most common mutation in subjects with HGPS is a de novo single-base pair substitution, G608G (GGC>GGT, within exon 11 of LMNA. This creates an abnormal splice donor site, leading to expression of a truncated protein. Results We studied a new case of a 5 year-old girl with HGPS and found a heterozygous point mutation, G608G, in LMNA. Complementary DNA sequencing of RNA showed that this mutation resulted in the deletion of 50 amino acids in the carboxyl-terminal tail domain of prelamin A. We characterized a primary dermal fibroblast cell line derived from the subject's skin. These cells expressed the mutant protein and exhibited a normal growth rate at early passage in primary culture but showed alterations in nuclear morphology. Expression levels and overall distributions of nuclear lamins and emerin, an integral protein of the inner nuclear membrane, were not dramatically altered. Ultrastructural analysis of the nuclear envelope using electron microscopy showed that chromatin is in close association to the nuclear lamina, even in areas with abnormal nuclear envelope morphology. The fibroblasts were hypersensitive to heat shock, and demonstrated a delayed response to heat stress. Conclusion Dermal fibroblasts from a subject with HGPS expressing a mutant truncated lamin A have dysmorphic nuclei, hypersensitivity to heat shock, and delayed response to heat stress. This suggests that the mutant protein, even when expressed at low levels, causes defective cell stability, which may be responsible for phenotypic

Mitochondrial Contribution to Parkinson's Disease Pathogenesis

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Anthony H. V. Schapira

2011-01-01

Full Text Available The identification of the etiologies and pathogenesis of Parkinson's disease (PD should play an important role in enabling the development of novel treatment strategies to prevent or slow the progression of the disease. The last few years have seen enormous progress in this respect. Abnormalities of mitochondrial function and increased free radical mediated damage were described in post mortem PD brain before the first gene mutations causing familial PD were published. Several genetic causes are now known to induce loss of dopaminergic cells and parkinsonism, and study of the mechanisms by which these mutations produce this effect has provided important insights into the pathogenesis of PD and confirmed mitochondrial dysfunction and oxidative stress pathways as central to PD pathogenesis. Abnormalities of protein metabolism including protein mis-folding and aggregation are also crucial to the pathology of PD. Genetic causes of PD have specifically highlighted the importance of mitochondrial dysfunction to PD: PINK1, parkin, DJ-1 and most recently alpha-synuclein proteins have been shown to localise to mitochondria and influence function. The turnover of mitochondria by autophagy (mitophagy has also become a focus of attention. This review summarises recent discoveries in the contribution of mitochondrial abnormalities to PD etiology and pathogenesis.

SuhB Is a Regulator of Multiple Virulence Genes and Essential for Pathogenesis of Pseudomonas aeruginosa

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Li, Kewei; Xu, Chang; Jin, Yongxin; Sun, Ziyu; Liu, Chang; Shi, Jing; Chen, Gukui; Chen, Ronghao; Jin, Shouguang; Wu, Weihui

2013-01-01

ABSTRACT During initial colonization and chronic infection, pathogenic bacteria encounter distinct host environments. Adjusting gene expression accordingly is essential for the pathogenesis. Pseudomonas aeruginosa has evolved complicated regulatory networks to regulate different sets of virulence factors to facilitate colonization and persistence. The type III secretion system (T3SS) and motility are associated with acute infections, while biofilm formation and the type VI secretion system (T6SS) are associated with chronic persistence. To identify novel regulatory genes required for pathogenesis, we screened a P. aeruginosa transposon (Tn) insertion library and found suhB to be an essential gene for the T3SS gene expression. The expression of suhB was upregulated in a mouse acute lung infection model, and loss of suhB resulted in avirulence. Suppression of T3SS gene expression in the suhB mutant is linked to a defective translation of the T3SS master regulator, ExsA. Further studies demonstrated that suhB mutation led to the upregulation of GacA and its downstream small RNAs, RsmY and RsmZ, triggering T6SS expression and biofilm formation while inhibiting the T3SS. Our results demonstrate that an in vivo-inducible gene, suhB, reciprocally regulates genes associated with acute and chronic infections and plays an essential role in the pathogenesis of P. aeruginosa. PMID:24169572

Pathogenesis Concept Of Extracranial Dissections In Iran

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Kavian Ghandehari

2017-02-01

Full Text Available Background: Dissection of Extracranial Internal Carotid Artery (EICA and Extracranial Vertebral Artery (EVA is an amportant cause of brain infarction with miscellaneous etiologies around the world. Methods: A prospective observational clinical study was conducted in Ghaem Hospital, Mashhad, Iran between 2008-2016. Diagnosis of brain infarction and TIA was made by stroke neurologist. Detection of EICA and EVA dissections were made by performing CT angiography  and MR angiography  or DSA in the suspected patients. Demographic features, clinical manifestations, territorial involvement, pathophysiology and pathogenesis of dissections were assessed in all of the patients. Pathogenesis of dissections was classified as Idiopathic, Trumatic, Postural and Genetic categories. Results: Twenty eight patients (21 males, 7 females were admitted with extracranial arterial dissection. Mean age of males and females with dissection was 39.81± 4.2 and 35.71±6.1 years respectively. Influence of gender on age of the patients was not significant, p>0.05. Among patients with extracranial dissection only 3.6% had atherosclerosis risk factors and 96.4% had no other cause for brain infarction. 100% of extracranial dissections in males occured in carotid territory, while 28.6% of females had dissection in the EVA. The influence of gender in territory of dissection was significant, p<0.05. Idiopathic dissections and genetic susceptibility was found in 10.7% and 3.6% of extracranial dissections respectively. 53.5% of the patienrs had trumatic pathogenesis for extracranial dissections and 32.1% developed dissection due to special neck  postures. Important details in pathophysiology and pathogenesis of extracranial dissections will be presented in the lecture. Conclusion: Stroke patients with extracranial dissections have characteristic demographic and  territorial involvement. Trumatic pathogenesis is the most frequent cause of dissection in Iran followed by neck

Oridonin attenuates Aβ1-42-induced neuroinflammation and inhibits NF-κB pathway.

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Sulei Wang

Full Text Available Neuroinflammation induced by beta-amyloid (Aβ plays a critical role in the pathogenesis of Alzheimer's disease (AD, and inhibiting Aβ-induced neuroinflammation serves as a potential strategy for the treatment of AD. Oridonin (Ori, a compound of Rabdosia rubescens, has been shown to exert anti-inflammatory effects. In this study, we demonstrated that Ori inhibited glial activation and decreased the release of inflammatory cytokines in the hippocampus of Aβ1-42-induced AD mice. In addition, Ori inhibited the NF-κB pathway and Aβ1-42-induced apoptosis. Furthermore, Ori could attenuate memory deficits in Aβ1-42-induced AD mice. In conclusion, our study demonstrated that Ori inhibited the neuroinflammation and attenuated memory deficits induced by Aβ1-42, suggesting that Ori might be a promising candidate for AD treatment.

Mast Cell Activation in Brain Injury, Stress, and Post-traumatic Stress Disorder and Alzheimer's Disease Pathogenesis.

Science.gov (United States)

Kempuraj, Duraisamy; Selvakumar, Govindhasamy P; Thangavel, Ramasamy; Ahmed, Mohammad E; Zaheer, Smita; Raikwar, Sudhanshu P; Iyer, Shankar S; Bhagavan, Sachin M; Beladakere-Ramaswamy, Swathi; Zaheer, Asgar

2017-01-01

review focusses on how mast cells in brain injuries, stress, and PTSD may promote the pathogenesis of AD. We suggest that inhibition of mast cells activation and brain cells associated inflammatory pathways in the brain injuries, stress, and PTSD can be explored as a new therapeutic target to delay or prevent the pathogenesis and severity of AD.

Mast Cell Activation in Brain Injury, Stress, and Post-traumatic Stress Disorder and Alzheimer's Disease Pathogenesis

Directory of Open Access Journals (Sweden)

Duraisamy Kempuraj

2017-12-01

including AD. This review focusses on how mast cells in brain injuries, stress, and PTSD may promote the pathogenesis of AD. We suggest that inhibition of mast cells activation and brain cells associated inflammatory pathways in the brain injuries, stress, and PTSD can be explored as a new therapeutic target to delay or prevent the pathogenesis and severity of AD.

Hepatitis E: Molecular Virology and Pathogenesis

Science.gov (United States)

Panda, Subrat K.; Varma, Satya P.K.

2013-01-01

Hepatitis E virus is a single, positive-sense, capped and poly A tailed RNA virus classified under the family Hepeviridae. Enteric transmission, acute self-limiting hepatitis, frequent epidemic and sporadic occurrence, high mortality in affected pregnants are hallmarks of hepatitis E infection. Lack of an efficient culture system and resulting reductionist approaches for the study of replication and pathogenesis of HEV made it to be a less understood agent. Early studies on animal models, sub-genomic expression of open reading frames (ORF) and infectious cDNA clones have helped in elucidating the genome organization, important stages in HEV replication and pathogenesis. The genome contains three ORF's and three untranslated regions (UTR). The 5′ distal ORF, ORF1 is translated by host ribosomes in a cap dependent manner to form the non-structural polyprotein including the viral replicase. HEV replicates via a negative-sense RNA intermediate which helps in the formation of the positive-sense genomic RNA and a single bi-cistronic sub-genomic RNA. The 3′ distal ORF's including the major structural protein pORF2 and the multifunctional host interacting protein pORF3 are translated from the sub-genomic RNA. Pathogenesis in HEV infections is not well articulated, and remains a concern due to the many aspects like host dependent and genotype specific variations. Animal HEV, zoonosis, chronicity in immunosuppressed patients, and rapid decompensation in affected chronic liver diseased patients warrants detailed investigation of the underlying pathogenesis. Recent advances about structure, entry, egress and functional characterization of ORF1 domains has furthered our understanding about HEV. This article is an effort to review our present understanding about molecular biology and pathogenesis of HEV. PMID:25755485

Overexpression of Hiwi Inhibits the Growth and Migration of Chronic Myeloid Leukemia Cells.

Science.gov (United States)

Wang, Yalin; Jiang, Yan; Ma, Ning; Sang, Bailu; Hu, Xiaolin; Cong, Xiaofeng; Liu, Ziling

2015-09-01

Chronic myeloid leukemia (CML) is a hematopoietic malignancy characterized by dysregulated growth and proliferation of hematopoietic stem/progenitor cells in bone marrow and excessive expansion of hematopoietic compartments in peripheral blood. Expression deletion of Hiwi, a human Piwi homolog, has been reported to be implicated in leukemogenesis. We here explored Hiwi's role in CML pathogenesis by determining how and whether its forced overexpression could affect CML cell growth and migration. The present results showed that lentivirus-mediated overexpression of Hiwi significantly suppressed cell proliferation and induced obvious apoptosis in K562 cells, a CML line cell line. Tumors in BALB/c nude mice generated by the K562 cells expressing Hiwi were much smaller than those formed by the control cells. Like in vitro, Hiwi upregulation induced cell apoptosis in the tumor tissues in vivo. Additionally, Hiwi elevation suppressed K562 cell migration and inhibited the activity and expression of matrix metalloproteinase-2 and -9. In summary, our study demonstrates that Hiwi overexpression inhibits CML cell growth and migration, providing insights into its role in CML pathogenesis.

Phosphorylation of Human Metapneumovirus M2-1 Protein Upregulates Viral Replication and Pathogenesis.

Science.gov (United States)

Cai, Hui; Zhang, Yu; Lu, Mijia; Liang, Xueya; Jennings, Ryan; Niewiesk, Stefan; Li, Jianrong

2016-08-15

Human metapneumovirus (hMPV) is a major causative agent of upper- and lower-respiratory-tract infections in infants, the elderly, and immunocompromised individuals worldwide. Like all pneumoviruses, hMPV encodes the zinc binding protein M2-1, which plays important regulatory roles in RNA synthesis. The M2-1 protein is phosphorylated, but the specific role(s) of the phosphorylation in viral replication and pathogenesis remains unknown. In this study, we found that hMPV M2-1 is phosphorylated at amino acid residues S57 and S60. Subsequent mutagenesis found that phosphorylation is not essential for zinc binding activity and oligomerization, whereas inhibition of zinc binding activity abolished the phosphorylation and oligomerization of the M2-1 protein. Using a reverse genetics system, recombinant hMPVs (rhMPVs) lacking either one or both phosphorylation sites in the M2-1 protein were recovered. These recombinant viruses had a significant decrease in both genomic RNA replication and mRNA transcription. In addition, these recombinant viruses were highly attenuated in cell culture and cotton rats. Importantly, rhMPVs lacking phosphorylation in the M2-1 protein triggered high levels of neutralizing antibody and provided complete protection against challenge with wild-type hMPV. Collectively, these data demonstrated that phosphorylation of the M2-1 protein upregulates hMPV RNA synthesis, replication, and pathogenesis in vivo The pneumoviruses include many important human and animal pathogens, such as human respiratory syncytial virus (hRSV), hMPV, bovine RSV, and avian metapneumovirus (aMPV). Among these viruses, hRSV and hMPV are the leading causes of acute respiratory tract infection in infants and children. Currently, there is no antiviral or vaccine to combat these diseases. All known pneumoviruses encode a zinc binding protein, M2-1, which is a transcriptional antitermination factor. In this work, we found that phosphorylation of M2-1 is essential for virus

Epigenetics and colorectal cancer pathogenesis.

Science.gov (United States)

Bardhan, Kankana; Liu, Kebin

2013-06-05

Colorectal cancer (CRC) develops through a multistage process that results from the progressive accumulation of genetic mutations, and frequently as a result of mutations in the Wnt signaling pathway. However, it has become evident over the past two decades that epigenetic alterations of the chromatin, particularly the chromatin components in the promoter regions of tumor suppressors and oncogenes, play key roles in CRC pathogenesis. Epigenetic regulation is organized at multiple levels, involving primarily DNA methylation and selective histone modifications in cancer cells. Assessment of the CRC epigenome has revealed that virtually all CRCs have aberrantly methylated genes and that the average CRC methylome has thousands of abnormally methylated genes. Although relatively less is known about the patterns of specific histone modifications in CRC, selective histone modifications and resultant chromatin conformation have been shown to act, in concert with DNA methylation, to regulate gene expression to mediate CRC pathogenesis. Moreover, it is now clear that not only DNA methylation but also histone modifications are reversible processes. The increased understanding of epigenetic regulation of gene expression in the context of CRC pathogenesis has led to development of epigenetic biomarkers for CRC diagnosis and epigenetic drugs for CRC therapy.

Epigenetics and Colorectal Cancer Pathogenesis

International Nuclear Information System (INIS)

Bardhan, Kankana; Liu, Kebin

2013-01-01

Colorectal cancer (CRC) develops through a multistage process that results from the progressive accumulation of genetic mutations, and frequently as a result of mutations in the Wnt signaling pathway. However, it has become evident over the past two decades that epigenetic alterations of the chromatin, particularly the chromatin components in the promoter regions of tumor suppressors and oncogenes, play key roles in CRC pathogenesis. Epigenetic regulation is organized at multiple levels, involving primarily DNA methylation and selective histone modifications in cancer cells. Assessment of the CRC epigenome has revealed that virtually all CRCs have aberrantly methylated genes and that the average CRC methylome has thousands of abnormally methylated genes. Although relatively less is known about the patterns of specific histone modifications in CRC, selective histone modifications and resultant chromatin conformation have been shown to act, in concert with DNA methylation, to regulate gene expression to mediate CRC pathogenesis. Moreover, it is now clear that not only DNA methylation but also histone modifications are reversible processes. The increased understanding of epigenetic regulation of gene expression in the context of CRC pathogenesis has led to development of epigenetic biomarkers for CRC diagnosis and epigenetic drugs for CRC therapy

Epigenetics and Colorectal Cancer Pathogenesis

Directory of Open Access Journals (Sweden)

Kebin Liu

2013-06-01

Full Text Available Colorectal cancer (CRC develops through a multistage process that results from the progressive accumulation of genetic mutations, and frequently as a result of mutations in the Wnt signaling pathway. However, it has become evident over the past two decades that epigenetic alterations of the chromatin, particularly the chromatin components in the promoter regions of tumor suppressors and oncogenes, play key roles in CRC pathogenesis. Epigenetic regulation is organized at multiple levels, involving primarily DNA methylation and selective histone modifications in cancer cells. Assessment of the CRC epigenome has revealed that virtually all CRCs have aberrantly methylated genes and that the average CRC methylome has thousands of abnormally methylated genes. Although relatively less is known about the patterns of specific histone modifications in CRC, selective histone modifications and resultant chromatin conformation have been shown to act, in concert with DNA methylation, to regulate gene expression to mediate CRC pathogenesis. Moreover, it is now clear that not only DNA methylation but also histone modifications are reversible processes. The increased understanding of epigenetic regulation of gene expression in the context of CRC pathogenesis has led to development of epigenetic biomarkers for CRC diagnosis and epigenetic drugs for CRC therapy.

Epigenetics and Colorectal Cancer Pathogenesis

Energy Technology Data Exchange (ETDEWEB)

Bardhan, Kankana; Liu, Kebin, E-mail: Kliu@gru.edu [Department of Biochemistry and Molecular Biology, Medical College of Georgia, and Cancer Center, Georgia Regents University, Augusta, GA 30912 (United States)

2013-06-05

Colorectal cancer (CRC) develops through a multistage process that results from the progressive accumulation of genetic mutations, and frequently as a result of mutations in the Wnt signaling pathway. However, it has become evident over the past two decades that epigenetic alterations of the chromatin, particularly the chromatin components in the promoter regions of tumor suppressors and oncogenes, play key roles in CRC pathogenesis. Epigenetic regulation is organized at multiple levels, involving primarily DNA methylation and selective histone modifications in cancer cells. Assessment of the CRC epigenome has revealed that virtually all CRCs have aberrantly methylated genes and that the average CRC methylome has thousands of abnormally methylated genes. Although relatively less is known about the patterns of specific histone modifications in CRC, selective histone modifications and resultant chromatin conformation have been shown to act, in concert with DNA methylation, to regulate gene expression to mediate CRC pathogenesis. Moreover, it is now clear that not only DNA methylation but also histone modifications are reversible processes. The increased understanding of epigenetic regulation of gene expression in the context of CRC pathogenesis has led to development of epigenetic biomarkers for CRC diagnosis and epigenetic drugs for CRC therapy.

Thrombomodulin inhibits the activation of eosinophils and mast cells.

Science.gov (United States)

Roeen, Ziaurahman; Toda, Masaaki; D'Alessandro-Gabazza, Corina N; Onishi, Masahiro; Kobayashi, Tetsu; Yasuma, Taro; Urawa, Masahito; Taguchi, Osamu; Gabazza, Esteban C

2015-01-01

Eosinophils and mast cells play critical roles in the pathogenesis of bronchial asthma. Activation of both cells leads to the release of pro-inflammatory mediators in the airway of asthmatic patients. Recently, we have shown that inhaled thrombomodulin inhibits allergic bronchial asthma in a mouse model. In the present study, we hypothesize that thrombomodulin can inhibit the activation of eosinophils and mast cells. The effect of thrombomodulin on the activation and release of inflammatory mediators from eosinophils and mast cells was evaluated. Thrombomodulin inhibited the eotaxin-induced chemotaxis, upregulation of CD11b and degranulation of eosinophils. Treatment with thrombomodulin also significantly suppressed the degranulation and synthesis of inflammatory cytokines and chemokines in eosinophils and mast cells. Mice treated with a low-dose of inhaled thrombomodulin have decreased number of eosinophils and activated mast cells and Th2 cytokines in the lungs compared to untreated mice. The results of this study suggest that thrombomodulin may modulate allergic responses by inhibiting the activation of both eosinophils and mast cells. Copyright © 2014 Elsevier Inc. All rights reserved.

Pathogenesis of Parkinson's disease

OpenAIRE

Riederer, Peter; Lange, Klaus W.

1992-01-01

The importance of genetic aspects, ageing, environmental factors, head trauma, defective mitochondrial respiration, altered iron metabolism, oxidative stress and glutamatergic overactivity of the basal ganglia in the pathogenesis of Parkinson's disease (PD) are considered in this review.

A crucial role of ROCK for alleviation of senescence-associated phenotype.

Science.gov (United States)

Park, Joon Tae; Kang, Hyun Tae; Park, Chi Hyun; Lee, Young-Sam; Cho, Kyung A; Park, Sang Chul

2018-06-01

In our previous study, we uncovered a novel mechanism in which amelioration of Hutchinson-Gilford progeria syndrome (HGPS) phenotype is mediated by mitochondrial functional recovery upon rho-associated protein kinase (ROCK) inhibition. However, it remains elusive whether this mechanism is also applied to the amelioration of normal aging cells. In this study, we used Y-27632 and fasudil as effective ROCK inhibitors, and examined their role in senescence. We found that ROCK inhibition induced the functional recovery of the mitochondria as well as the metabolic reprogramming, which are two salient features that are altered in normal aging cells. Moreover, microarray analysis revealed that the up-regulated pathway upon ROCK inhibition is enriched for chromatin remodeling genes, which may play an important role in the alleviation of senescence-associated cell cycle arrest. Indeed, ROCK inhibition induced cellular proliferation, concomitant with the amelioration of senescent phenotype. Furthermore, the restorative effect by ROCK inhibition was observed in vivo as evidenced by the facilitated cutaneous wound healing. Taken together, our data indicate that ROCK inhibition might be utilized to ameliorate normal aging process and to treat age-related disease. Copyright © 2018 Elsevier Inc. All rights reserved.

International consensus guidelines for scoring the histopathological growth patterns of liver metastasis

DEFF Research Database (Denmark)

Van Dam, Pieter Jan; Van Der Stok, Eric P.; Teuwen, Laure Anne

2017-01-01

.Results:Good-to-excellent correlations (intraclass correlation coefficient >0.5) with the gold standard were obtained for the assessment of the replacement HGP and desmoplastic HGP. Overall survival was significantly superior in the desmoplastic HGP subgroup compared with the replacement or pushing HGP subgroup (P=0.006).Conclusions:The...... that is present in each pattern and can be scored from standard haematoxylin-and-eosin-stained (H&E) tissue sections. The current study provides consensus guidelines for scoring these HGPs.Methods:Guidelines for defining the HGPs were established by a large international team. To assess the validity...

Tryptophan-induced pathogenesis of breast cancer | Cao | African ...

African Journals Online (AJOL)

Background: The pathogenesis of breast cancer remains unclear. Aims: To investigate the pathogenesis of breast cancer through targeted metabolomics of amino acids components in serum of patients with breast cancer. Methods: Patients with breast cancers were enrolled in our hospital between year January 1st, 2013 ...

Inhibition of Hedgehog signaling antagonizes serous ovarian cancer growth in a primary xenograft model.

Directory of Open Access Journals (Sweden)

Christopher K McCann

Full Text Available Recent evidence links aberrant activation of Hedgehog (Hh signaling with the pathogenesis of several cancers including medulloblastoma, basal cell, small cell lung, pancreatic, prostate and ovarian. This investigation was designed to determine if inhibition of this pathway could inhibit serous ovarian cancer growth.We utilized an in vivo pre-clinical model of serous ovarian cancer to characterize the anti-tumor activity of Hh pathway inhibitors cyclopamine and a clinically applicable derivative, IPI-926. Primary human serous ovarian tumor tissue was used to generate tumor xenografts in mice that were subsequently treated with cyclopamine or IPI-926.Both compounds demonstrated significant anti-tumor activity as single agents. When IPI-926 was used in combination with paclitaxel and carboplatinum (T/C, no synergistic effect was observed, though sustained treatment with IPI-926 after cessation of T/C continued to suppress tumor growth. Hh pathway activity was analyzed by RT-PCR to assess changes in Gli1 transcript levels. A single dose of IPI-926 inhibited mouse stromal Gli1 transcript levels at 24 hours with unchanged human intra-tumor Gli1 levels. Chronic IPI-926 therapy for 21 days, however, inhibited Hh signaling in both mouse stromal and human tumor cells. Expression data from the micro-dissected stroma in human serous ovarian tumors confirmed the presence of Gli1 transcript and a significant association between elevated Gli1 transcript levels and worsened survival.IPI-926 treatment inhibits serous tumor growth suggesting the Hh signaling pathway contributes to the pathogenesis of ovarian cancer and may hold promise as a novel therapeutic target, especially in the maintenance setting.

Pathogenesis of Nervous and Mental Diseases in Children.

Science.gov (United States)

Harms, Ernest, Ed.

Major pathogenic sources of mental diseases in children and a classification of these diseases are considered. Contributions include the following: pathogenesis of mental diseases in childhood by Ernest Harms, organ inferiority and psychiatric disorders by Bernard Shulman and Howard Klapman, pathogenesis of neurological disorders by George Gold,…

Molecular Pathogenesis of Spondyloarthritis

DEFF Research Database (Denmark)

Carlsen, Thomas Gelsing

This dissertation includes a presentation of knowledge on the molecular pathogenesis of spondyloarthritis achieved through a PhD programme at Aalborg University from 1.12.2011 - 1.12.2014. Work was carried out in the Laboratory of Medical Mass Spectrometry, headed by: Professor Svend Birkelund...

Modern concepts of pathogenesis of ichthyosis

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Світлана Володимирівна Дмитренко

2015-06-01

Full Text Available The modern concepts of ichthyosis are rather ambiguous and need more precise definition. The modern conception of pathogenesis of ichthysosis is offered and considered in this article.Aim. An aim is to analyze received data of our researches about molecular disturbances of keratin on the background of ichthyosis and the current data on the pathogenesis of disease.Materials and methods. An analysis of the results of research in 70 patients with ichthyosis by the methods of the flow cytometry, immunohistochemistry and by immunologic methods is presented in an article.Results. Authors revealed molecular, immunologic and immunohistochemical changes that realizes the disturbance of keratinization on the background of this disease. The model of pathogenesis of the various manifestations of gene mutations that causes ichthyosis is proposed and it can be taken into account when elaborating the new directions of therapy.Conclusions. Gene mutations that cause ichthyosis realizes on the background of disturbance of the cell cycle causing cornification and disturb the local and general immune reactions that summarily lead to the clinical presentations of disease. 

Role of the serine-rich surface glycoprotein Srr1 of Streptococcus agalactiae in the pathogenesis of infective endocarditis.

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Ho Seong Seo

Full Text Available The binding of bacteria to fibrinogen and platelets are important events in the pathogenesis of infective endocarditis. Srr1 is a serine-rich repeat glycoprotein of Streptococcus agalactiae that binds directly to the Aα chain of human fibrinogen. To assess the impact of Srr1 on the pathogenesis of endocarditis due to S. agalactiae, we first examined the binding of this organism to immobilized human platelets. Strains expressing Srr1 had significantly higher levels of binding to human platelets in vitro, as compared with isogenic Δsrr1 mutants. In addition, platelet binding was inhibited by pretreatment with anti-fibrinogen IgG or purified Srr1 binding region. To assess the contribution of Srr1 to pathogenicity, we compared the relative virulence of S. agalactiae NCTC 10/84 strain and its Δsrr1 mutant in a rat model of endocarditis, where animals were co-infected with the WT and the mutant strains at a 1:1 ratio. At 72 h post-infection, bacterial densities (CFU/g of the WT strain within vegetations, kidneys, and spleens were significantly higher, as compared with the Δsrr1 mutant. These results indicate that Srr1 contributes to the pathogenesis of endocarditis due to S. agalactiae, at least in part through its role in fibrinogen-mediated platelet binding.

Update on mucormycosis pathogenesis.

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Ibrahim, Ashraf S; Kontoyiannis, Dimitrios P

2013-12-01

Mucormycosis is an increasingly common fungal infection with unacceptably high mortality. The recent sequencing genome projects of Mucorales and the development of gene manipulation have enabled significant advances in understanding the pathogenesis of mucormycosis. Therefore, we review the pathogenesis of mucormycosis and highlight potential development of novel diagnostic and therapeutic modalities against this lethal disease. Much of the work has been focused on the role of iron uptake in the virulence of Mucorales. Additionally, host receptors and fungal ligands involved in the process of tissue invasion as well as sporangiospore size and sex loci and their contribution to virulence of Mucorales are discussed. Finally, the role of innate and adaptive immunity in protection against Mucorales and new evidence about drug-induced apoptosis in these fungi are discussed. Recent discoveries introduce several potentially novel diagnostic and therapeutic modalities, which are likely to improve management and outcome for mucormycosis. Future preclinical and clinical research is warranted to develop these diagnostic and therapeutic strategies.

Contribution of pertussis toxin to the pathogenesis of pertussis disease

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Carbonetti, Nicholas H.

2015-01-01

Pertussis toxin (PT) is a multisubunit protein toxin secreted by Bordetella pertussis, the bacterial agent of the disease pertussis or whooping cough. PT in detoxified form is a component of all licensed acellular pertussis vaccines, since it is considered to be an important virulence factor for this pathogen. PT inhibits G protein-coupled receptor signaling through Gi proteins in mammalian cells, an activity that has led to its widespread use as a cell biology tool. But how does this activity of PT contribute to pertussis, including the severe respiratory symptoms of this disease? In this minireview, the contribution of PT to the pathogenesis of pertussis disease will be considered based on evidence from both human infections and animal model studies. Although definitive proof of the role of PT in humans is lacking, substantial evidence supports the idea that PT is a major contributor to pertussis pathology, including the severe respiratory symptoms associated with this disease. PMID:26394801

[Epidemiology, risk factors and molecular pathogenesis of primary liver cancer].

Science.gov (United States)

Hagymási, Krisztina; Tulassay, Zsolt

2008-03-23

Primary liver cancer is the fifth most common cancer worldwide. Hepatocellular carcinoma accounts for 85-90% of primary liver cancers. Distribution of hepatocellular carcinoma shows variations among geographic regions and ethnic groups. Males have higher liver cancer rates than females. Hepatocellular carcinoma occurs within an established background of chronic liver disease and cirrhosis (70-90%). Major causes (80%) of hepatocellular carcinoma are hepatitis B, C virus infection, and aflatoxin exposition. Its development is a multistep process. We have a growing understanding on the molecular pathogenesis. Genetic and epigenetic changes activate oncogenes, inhibit tumorsuppressor genes, which result in autonomous cell proliferation. The chromosomal instability caused by telomere dysfunction, the growth-retrained environment and the alterations of the micro- and macroenvironment help the expansion of the malignant cells. Understanding the molecular mechanisms could improve the screening of patients with chronic liver disease, or cirrhosis, and the prevention as well as treatment of hepatocellular carcinoma.

Pathogenesis of Dengue Vaccine Viruses in Mosquitoes.

Science.gov (United States)

1980-01-01

1973). Sabin (1948) showed that attenuated dpngiie, passed through mosquitoes, did not revert to pathogenicity frnr man. -7- Thus even if the vaccine ...AD-A138 518 PATHOGENESIS OF DENGUE VACCINE YIRUSES IN MOSQUITOES 1/ (U) YALE UNIV NEW HAVEN CONN SCHOOL OF MEDICINE B J BEATY ET AL. 9i JAN 80 DRND7...34 ’ UNCLASSIFIED 0{) AD 0Pathogenesis of dengue vaccine viruses in mosquitoes -First Annual Report Barry I. Beaty, Ph.D. Thomas H. G

Reverse correlation of Jab1 and Smad4 in PANC-1 cells involved in the pathogenesis of pancreatic cancer.

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Li, Jun; Gu, Zhuoyu; Li, Siyuan; Xiao, Zhiwei; Sun, Kan

2015-01-01

Steps in the genetic basis of pancreatic cancer (PC) have been recently identified, however, Studies focusing on the relationship between Jab1 and Smad4 in PC are rarely reported. This study was performed to examine the expression patterns and association of Jab1 and Smad4 in PC cells for gaining a further understanding of PC pathogenesis. Human pancreatic cancer cell line PANC-1 cells were infected with retrovirus vector containing GFP, HA-Jab1, siGFP, and siJab1 respectively. The expression of Jab1 and Smad4 in PANC-1 cells was analyzed by Western blot and immunocytochemistry. Subsequently, the effect of overexpression of Jab1 on cell proliferation inhibition mediated by TGF-β was examined with MTT colorimetry. The expression of Smad4 in PANC-1 cells was inhibited after the overexpression of Jab1. Inversely, the expression of Smad4 was increased after the down-regulation of Jab1 silenced by SiRNA. Smad4 expression in PANC-1 cells was negatively correlated with Jab1 expression. In addition, the cell proliferation inhibitory effect induced by TGF-β in PANC-1 cells was attenuated after the overexpression of Jab1. The reverse correlation of Jab1 and Smad4 in PANC-1 cells may be involved in the Pathogenesis of PC. Jab1 can cause degradation of Smad4 via TGF-β signal pathway, consequently contributing to the proliferation of PC cells.

Overexpression of Cullin7 is associated with hepatocellular carcinoma progression and pathogenesis.

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An, Jun; Zhang, Zhigang; Liu, Zhiyong; Wang, Ruizhi; Hui, Dayang; Jin, Yi

2017-12-06

Overexpression of Cullin7 is associated with some types of malignancies. However, the part of Cullin7 in hepatocellular carcinoma remains unclear. The aim of this study was to investigate the role of Cullin7 in pathogenesis and the progression of hepatocellular carcinoma. In the present study, the expression of Cullin7 in hepatocellular carcinoma cell lines and five surgical hepatocellular carcinoma specimens was detected with quantitative reverse transcription PCR and western blotting. In addition, the protein expression of Cullin7 was examined in 162 cases of archived hepatocellular carcinoma using immunohistochemistry. We found elevated expression of both mRNA and protein levels of Cullin7 in hepatocellular carcinoma cell lines, and Cullin7 protein was significantly upregulated in hepatocellular carcinoma compared with paired normal hepatic tissues. The immunohistochemistry analysis revealed that overexpression of Cullin7 occurred in 69.1% of hepatocellular carcinoma samples, which was a significantly higher rate than that in adjacent normal hepatic tissue (P hepatocellular carcinoma HepG2 cells, we revealed that Cullin7 could significantly enhance cell proliferation, growth, migration and invasion. Conversely, knocking down Cullin7 expression with short hairpin RNAi in hepatocellular carcinoma HepG2 cells inhibited cell proliferation, growth, migration and invasion. Our studies provide evidence that overexpression of Cullin7 plays an important role in the pathogenesis and progression of hepatocellular carcinoma and may be a valuable marker for hepatocellular carcinoma management.

Demonstrating concepts of pathogenesis using effectors of Phytophthora infestans

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Pathogenesis, or how pathogens cause disease, is an important concept in plant pathology. The study of pathogenesis in plant pathology has rapidly expanded and is now a significant portion of plant pathology research (especially research at the molecular level of host-pathogen interaction). With the...

[Morphology and pathogenesis of visceral manifestations of chronic alcoholism].

Science.gov (United States)

Lebedev, S P

1982-01-01

Chronic alcoholism is accompanied by systemic involvement of the internal organs. Clinico-morphological forms of chronic alcoholism are distinguished on the basis of the prevailing organ pathology, Morphological data are presented, and pathogenesis of the lesions of the liver, heart, pancreas, and kidneys in patients with chronic alcoholism is analysed. The hepatic form may present alcoholic dystrophy, hepatitis or cirrhosis which are stages of progressing hepatopathy. The toxic and metabolic effect of ethanol is important in the pathogenesis of liver lesion. The cardiac form is characterized by the development of alcoholic myocardiodystrophy. In addition to the toxic influence of ethanol, hormonal and electrolyte changes and microcirculatory disorders play a role in its pathogenesis. Chronic calcifying pancreatitis in chronic alcoholism is associated with the effect of ethanol on the mediatory system. The renal form any present necronephrosis, hepatorenal syndrome, glomerulonephritis or pyelonephritis. Their pathogenesis is determined by toxicity of ethanol, circulation of immune complexes in the blood, or immunosuppression.

Research advances in the pathogenesis of nonalcoholic fatty liver disease

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WANG Hu

2017-04-01

Full Text Available Nonalcoholic fatty liver disease (NAFLD has been developing rapidly in recent years and has become one of the most common liver diseases. However, its pathogenesis remains unclear, and there are no widely accepted therapeutic regimens. NAFLD has a complex pathogenesis with multiple factors involved, including insulin resistance, oxidative stress, bile acid metabolic disorders, and autophagy. This article reviews the pathogenesis of NAFLD in order to provide a reference for further research and clinical treatment in the future.

Bordetella pertussis pathogenesis: current and future challenges

Science.gov (United States)

Melvin, Jeffrey A.; Scheller, Erich V.; Miller, Jeff F.; Cotter, Peggy A.

2014-01-01

Pertussis, or whooping cough, has recently reemerged as a major public health threat despite high levels of vaccination against the etiological agent, Bordetella pertussis. In this Review, we describe the pathogenesis of this disease, with a focus on recent mechanistic insights into virulence factor function. We also discuss the changing epidemiology of pertussis and the challenges of vaccine development. Despite decades of research, many aspects of B. pertussis physiology and pathogenesis remain poorly understood. We highlight knowledge gaps that must be addressed to develop improved vaccines and therapeutic strategies. PMID:24608338

Signaling Pathways in Pathogenesis of Diamond Blackfan Anemia

Science.gov (United States)

2015-12-01

AWARD NUMBER: W81XWH-12-1-0590 TITLE: SIGNALING PATHWAYS IN PATHOGENESIS OF DIAMOND BLACKFAN ANEMIA PRINCIPAL INVESTIGATOR: KATHLEEN M...SUBTITLE 5a. CONTRACT NUMBER W81XWH-12-1-0590 SIGNALING PATHWAYS IN PATHOGENESIS OF DIAMOND BLACKFAN ANEMIA 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER...Unlimited 13. SUPPLEMENTARY NOTES None 14. ABSTRACT: Diamond Blackfan Anemia (DBA) is a disorder that results in pure red cell aplasia, congenital

Inhibition of Myeloperoxidase at the Peak of Experimental Autoimmune Encephalomyelitis Restores Blood-Brain-Barrier Integrity and Ameliorates Disease Severity.

Science.gov (United States)

Zhang, Hao; Ray, Avijit; Miller, Nichole M; Hartwig, Danielle; Pritchard, Kirkwood A; Dittel, Bonnie N

2015-11-12

Oxidative stress is thought to contribute to disease pathogenesis in the central nervous system (CNS) disease multiple sclerosis (MS). Myeloperoxidase (MPO), a potent peroxidase that generates toxic radicals and oxidants, is increased in the CNS during MS. However, the exact mechanism whereby MPO drives MS pathology is not known. We addressed this question by inhibiting MPO in mice with experimental autoimmune encephalomyelitis (EAE) using our non-toxic MPO inhibitor KYC. We found that therapeutic administration of KYC for five days starting at the peak of disease significantly attenuated EAE disease severity, reduced myeloid cell numbers and permeability of the blood-brain-barrier (BBB). These data indicate that inhibition of MPO by KYC restores BBB integrity thereby limiting migration of myeloid cells into the CNS that drive EAE pathogenesis. In addition, these observations indicate that KYC may be an effective therapeutic agent for the treatment of MS. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Transposon mutagenesis reveals differential pathogenesis of Ralstonia solanacearum on tomato and Arabidopsis.

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Lin, Yu-Mei; Chou, I-Chun; Wang, Jaw-Fen; Ho, Fang-I; Chu, Yu-Ju; Huang, Pei-Cheng; Lu, Der-Kang; Shen, Hwei-Ling; Elbaz, Mounira; Huang, Shu-Mei; Cheng, Chiu-Ping

2008-09-01

Ralstonia solanacearum causes a deadly wilting disease on a wide range of crops. To elucidate pathogenesis of this bacterium in different host plants, we set out to identify R. solanacearum genes involved in pathogenesis by screening random transposon insertion mutants of a highly virulent strain, Pss190, on tomato and Arabidopsis thaliana. Mutants exhibiting various decreased virulence levels on these two hosts were identified. Sequence analysis showed that most, but not all, of the identified pathogenesis genes are conserved among distinct R. solanacearum strains. A few of the disrupted loci were not reported previously as being involved in R. solanacearum pathogenesis. Notably, a group of mutants exhibited differential pathogenesis on tomato and Arabidopsis. These results were confirmed by characterizing allelic mutants in one other R. solanacearum strain of the same phylotype. The significantly decreased mutants' colonization in Arabidopsis was found to be correlated with differential pathogenesis on these two plants. Differential requirement of virulence genes suggests adaptation of this bacterium in different host environments. Together, this study reveals commonalities and differences of R. solanacearum pathogenesis on single solanaceous and nonsolanaceous hosts, and provides important new insights into interactions between R. solanacearum and different host plants.

Particle swarm optimization based fuzzy logic controller for autonomous green power energy system with hydrogen storage

International Nuclear Information System (INIS)

Safari, S.; Ardehali, M.M.; Sirizi, M.J.

2013-01-01

Highlights: ► Optimized fuzzy logic controller for a hybrid green power system is developed. ► PSO algorithm is used to optimize membership functions of controller. ► Optimized fuzzy logic controller results in lower O and M costs and LPSP. ► Optimization results in less variation of battery state of charge. - Abstract: The objective of this study is to develop an optimized fuzzy logic controller (FLC) for operating an autonomous hybrid green power system (HGPS) based on the particle swarm optimization (PSO) algorithm. An electrolyzer produces hydrogen from surplus energy generated by the wind turbine and photovoltaic array of HGPS for later use by a fuel cell. The PSO algorithm is used to optimize membership functions of the FLC. The FLC inputs are (a) net power flow and (b) batteries state of charge (SOC) and FLC output determines the time for hydrogen production or consumption. Actual data for weekly residential load, wind speed, ambient temperature, and solar irradiation are used for performance simulation and analysis of the HGPS examined. The weekly operation and maintenance (O and M) costs and the loss of power supply probability (LPSP) are considered in the optimization procedure. It is determined that FLC optimization results in (a) reduced fluctuations in batteries SOC which translates into longer life for batteries and the average SOC is increased by 6.18% and (b) less working hours for fuel cell, when the load is met by wind and PV. It is found that the optimized FLC results in lower O and M costs and LPSP by 57% and 33%, respectively, as compared to its un-optimized counterpart. In addition, a reduction of 18% in investment cost is achievable by optimal sizing and reducing the capacity of HGPS equipment.

Diabetic Cataract—Pathogenesis, Epidemiology and Treatment

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Andreas Pollreisz

2010-01-01

This paper provides an overview of the pathogenesis of diabetic cataract, clinical studies investigating the association between diabetes and cataract development, and current treatment of cataract in diabetics.

Nutritional rickets: pathogenesis and prevention.

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Pettifor, John M

2013-06-01

Nutritional rickets remains a public health concern in many areas of the world despite cheap and effective means of preventing the disease. The roles of vitamin D deficiency, low dietary calcium intakes and the interrelationships between the two in the pathogenesis of the disease are discussed. It is now recognized that vitamin D deficiency in the pregnant and lactating mother predisposes to the development of rickets in the breastfed infant, and that cultural and social factors are important in the pathogenesis of the disease during the adolescent growth spurt. Prevention of rickets is dependent on the awareness of the medical profession and the general public of the need to ensure adequate intakes of vitamin D in at-risk populations, and of the importance of increasing dietary intakes of calcium using locally available and inexpensive foods in communities in which dietary calcium deficiency rickets is prevalent.

The role of Src kinase in the biology and pathogenesis of Acanthamoeba castellanii

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Siddiqui Ruqaiyyah

2012-06-01

Full Text Available Abstract Background Acanthamoeba species are the causative agents of fatal granulomatous encephalitis in humans. Haematogenous spread is thought to be a primary step, followed by blood–brain barrier penetration, in the transmission of Acanthmaoeba into the central nervous system, but the associated molecular mechanisms remain unclear. Here, we evaluated the role of Src, a non-receptor protein tyrosine kinase in the biology and pathogenesis of Acanthamoeba. Methods Amoebistatic and amoebicidal assays were performed by incubating amoeba in the presence of Src kinase-selective inhibitor, PP2 (4-amino-5-(4-chlorophenyl-7-(t-butylpyrazolo[3,4-d]pyrimidine and its inactive analog, PP3 (4-amino-7-phenylpyrazolo[3,4-d]pyrimidine. Using this inhibitor, the role of Src kinase in A. castellanii interactions with Escherichia coli was determined. Zymographic assays were performed to study effects of Src kinase on extracellular proteolytic activities of A. castellanii. The human brain microvascular endothelial cells were used to determine the effects of Src kinase on A. castellanii adhesion to and cytotoxicity of host cells. Results Inhibition of Src kinase using a specific inhibitor, PP2 (4-amino-5-(4 chlorophenyl-7-(t-butylpyrazolo [3,4-d] pyrimidine but not its inactive analog, PP3 (4-amino-7-phenylpyrazolo[3,4-d] pyrimidine, had detrimental effects on the growth of A. castellanii (keratitis isolate, belonging to the T4 genotype. Interestingly, inhibition of Src kinase hampered the phagocytic ability of A. castellanii, as measured by the uptake of non-invasive bacteria, but, on the contrary, invasion by pathogenic bacteria was enhanced. Zymographic assays revealed that inhibition of Src kinases reduced extracellular protease activities of A. castellanii. Src kinase inhibition had no significant effect on A. castellanii binding to and cytotoxicity of primary human brain microvascular endothelial cells, which constitute the blood–brain barrier

Methamphetamine inhibits HIV-1 replication in CD4+ T cells by modulating anti-HIV-1 miRNA expression.

Science.gov (United States)

Mantri, Chinmay K; Mantri, Jyoti V; Pandhare, Jui; Dash, Chandravanu

2014-01-01

Methamphetamine is the second most frequently used illicit drug in the United States. Methamphetamine abuse is associated with increased risk of HIV-1 acquisition, higher viral loads, and enhanced HIV-1 pathogenesis. Although a direct link between methamphetamine abuse and HIV-1 pathogenesis remains to be established in patients, methamphetamine has been shown to increase HIV-1 replication in macrophages, dendritic cells, and cells of HIV transgenic mice. Intriguingly, the effects of methamphetamine on HIV-1 replication in human CD4(+) T cells that serve as the primary targets of infection in vivo are not clearly understood. Therefore, we examined HIV-1 replication in primary CD4(+) T cells in the presence of methamphetamine in a dose-dependent manner. Our results demonstrate that methamphetamine had a minimal effect on HIV-1 replication at concentrations of 1 to 50 μmol/L. However, at concentrations >100 μmol/L, it inhibited HIV-1 replication in a dose-dependent manner. We also discovered that methamphetamine up-regulated the cellular anti-HIV-1 microRNAs (miR-125b, miR-150, and miR-28-5p) in CD4(+) T cells. Knockdown experiments illustrated that up-regulation of the anti-HIV miRNAs inhibited HIV-1 replication. These results are contrary to the paradigm that methamphetamine accentuates HIV-1 pathogenesis by increasing HIV-1 replication. Therefore, our findings underline the complex interaction between drug use and HIV-1 and necessitate comprehensive understanding of the effects of methamphetamine on HIV-1 pathogenesis. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

On the pathogenesis of IDDM

DEFF Research Database (Denmark)

Nerup, J; Mandrup-Poulsen, Thomas; Helqvist, S

1994-01-01

A model of the pathogenesis of insulin-dependent diabetes mellitus, i.e. the initial phase of beta-cell destruction, is proposed: in a cascade-like fashion efficient antigen presentation, unbalanced cytokine, secretion and poor beta-cell defence result in beta-cell destruction by toxic free...

Duckweed (Lemna minor) as a Model Plant System for the Study of Human Microbial Pathogenesis

Science.gov (United States)

Zhang, Yong; Hu, Yangbo; Yang, Baoyu; Ma, Fang; Lu, Pei; Li, Lamei; Wan, Chengsong; Rayner, Simon; Chen, Shiyun

2010-01-01

Background Plant infection models provide certain advantages over animal models in the study of pathogenesis. However, current plant models face some limitations, e.g., plant and pathogen cannot co-culture in a contained environment. Development of such a plant model is needed to better illustrate host-pathogen interactions. Methodology/Principal Findings We describe a novel model plant system for the study of human pathogenic bacterial infection on a large scale. This system was initiated by co-cultivation of axenic duckweed (Lemna minor) plants with pathogenic bacteria in 24-well polystyrene cell culture plate. Pathogenesis of bacteria to duckweed was demonstrated with Pseudomonas aeruginosa and Staphylococcus aureus as two model pathogens. P. aeruginosa PAO1 caused severe detriment to duckweed as judged from inhibition to frond multiplication and chlorophyll formation. Using a GFP-marked PAO1 strain, we demonstrated that bacteria colonized on both fronds and roots and formed biofilms. Virulence of PAO1 to duckweed was attenuated in its quorum sensing (QS) mutants and in recombinant strains overexpressing the QS quenching enzymes. RN4220, a virulent strain of S. aureus, caused severe toxicity to duckweed while an avirulent strain showed little effect. Using this system for antimicrobial chemical selection, green tea polyphenols exhibited inhibitory activity against S. aureus virulence. This system was further confirmed to be effective as a pathogenesis model using a number of pathogenic bacterial species. Conclusions/Significance Our results demonstrate that duckweed can be used as a fast, inexpensive and reproducible model plant system for the study of host-pathogen interactions, could serve as an alternative choice for the study of some virulence factors, and could also potentially be used in large-scale screening for the discovery of antimicrobial chemicals. PMID:21049039

Duckweed (Lemna minor as a model plant system for the study of human microbial pathogenesis.

Directory of Open Access Journals (Sweden)

Yong Zhang

Full Text Available BACKGROUND: Plant infection models provide certain advantages over animal models in the study of pathogenesis. However, current plant models face some limitations, e.g., plant and pathogen cannot co-culture in a contained environment. Development of such a plant model is needed to better illustrate host-pathogen interactions. METHODOLOGY/PRINCIPAL FINDINGS: We describe a novel model plant system for the study of human pathogenic bacterial infection on a large scale. This system was initiated by co-cultivation of axenic duckweed (Lemna minor plants with pathogenic bacteria in 24-well polystyrene cell culture plate. Pathogenesis of bacteria to duckweed was demonstrated with Pseudomonas aeruginosa and Staphylococcus aureus as two model pathogens. P. aeruginosa PAO1 caused severe detriment to duckweed as judged from inhibition to frond multiplication and chlorophyll formation. Using a GFP-marked PAO1 strain, we demonstrated that bacteria colonized on both fronds and roots and formed biofilms. Virulence of PAO1 to duckweed was attenuated in its quorum sensing (QS mutants and in recombinant strains overexpressing the QS quenching enzymes. RN4220, a virulent strain of S. aureus, caused severe toxicity to duckweed while an avirulent strain showed little effect. Using this system for antimicrobial chemical selection, green tea polyphenols exhibited inhibitory activity against S. aureus virulence. This system was further confirmed to be effective as a pathogenesis model using a number of pathogenic bacterial species. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that duckweed can be used as a fast, inexpensive and reproducible model plant system for the study of host-pathogen interactions, could serve as an alternative choice for the study of some virulence factors, and could also potentially be used in large-scale screening for the discovery of antimicrobial chemicals.

Poxvirus-encoded TNF decoy receptors inhibit the biological activity of transmembrane TNF.

Science.gov (United States)

Pontejo, Sergio M; Alejo, Ali; Alcami, Antonio

2015-10-01

Poxviruses encode up to four different soluble TNF receptors, named cytokine response modifier B (CrmB), CrmC, CrmD and CrmE. These proteins mimic the extracellular domain of the cellular TNF receptors to bind and inhibit the activity of TNF and, in some cases, other TNF superfamily ligands. Most of these ligands are released after the enzymic cleavage of a membrane precursor. However, transmembrane TNF (tmTNF) is not only a precursor of soluble TNF but also exerts specific pro-inflammatory and immunological activities. Here, we report that viral TNF receptors bound and inhibited tmTNF and describe some interesting differences in their activity against the soluble cytokine. Thus, CrmE, which does not inhibit mouse soluble TNF, could block murine tmTNF-induced cytotoxicity. We propose that this anti-tmTNF effect should be taken into consideration when assessing the role of viral TNF decoy receptors in the pathogenesis of poxvirus.

The inhibition of anti-DNA binding to DNA by nucleic acid binding polymers.

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Nancy A Stearns

Full Text Available Antibodies to DNA (anti-DNA are the serological hallmark of systemic lupus erythematosus (SLE and can mediate disease pathogenesis by the formation of immune complexes. Since blocking immune complex formation can attenuate disease manifestations, the effects of nucleic acid binding polymers (NABPs on anti-DNA binding in vitro were investigated. The compounds tested included polyamidoamine dendrimer, 1,4-diaminobutane core, generation 3.0 (PAMAM-G3, hexadimethrine bromide, and a β-cylodextrin-containing polycation. As shown with plasma from patients with SLE, NABPs can inhibit anti-DNA antibody binding in ELISA assays. The inhibition was specific since the NABPs did not affect binding to tetanus toxoid or the Sm protein, another lupus autoantigen. Furthermore, the polymers could displace antibody from preformed complexes. Together, these results indicate that NABPs can inhibit the formation of immune complexes and may represent a new approach to treatment.

Theories on the Pathogenesis of Endometriosis

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Samer Sourial

2014-01-01

Full Text Available Endometriosis is a common, chronic inflammatory disease defined by the presence of extrauterine endometrial tissue. The aetiology of endometriosis is complex and multifactorial, where several not fully confirmed theories describe its pathogenesis. This review examines existing theories on the initiation and propagation of different types of endometriotic lesions, as well as critically appraises the myriad of biologically relevant evidence that support or oppose each of the proposed theories. The current literature suggests that stem cells, dysfunctional immune response, genetic predisposition, and aberrant peritoneal environment may all be involved in the establishment and propagation of endometriotic lesions. An orchestrated scientific and clinical effort is needed to consider all factors involved in the pathogenesis of this multifaceted disease and to propose novel therapeutic targets to reach effective treatments for this distressing condition.

miR-613 inhibits proliferation and invasion of breast cancer cell via VEGFA

Energy Technology Data Exchange (ETDEWEB)

Wu, Junzhao; Yuan, Peng; Mao, Qixin [Breast Surgery, The Affiliated Cancer Hospital of Zhengzhou University, Henan (China); Lu, Peng [Gastrointestinal Surgery Department, People' s Hospital of Zhengzhou, Henan (China); Xie, Tian; Yang, Hanzhao [Breast Surgery, The Affiliated Cancer Hospital of Zhengzhou University, Henan (China); Wang, Chengzheng, E-mail: wangchengzheng@126.com [Breast Surgery, The Affiliated Cancer Hospital of Zhengzhou University, Henan (China)

2016-09-09

MicroRNAs (miRNAs) play important roles in the pathogenesis of many types of cancers by negatively regulating gene expression at posttranscriptional level. However, the role of microRNAs in breast cancer, has remained elusive. Here, we identified that miR-613 inhibits breast cancer cell proliferation by negatively regulates its target gene VEGFA. In breast cancer cell lines, CCK-8 proliferation assay indicated that the cell proliferation was inhibited by miR-613, while miR-613 inhibitor significantly promoted the cell proliferation. Transwell assay showed that miR-613 mimics significantly inhibited the migration and invasion of breast cancer cells, whereas miR-613 inhibitors significantly increased cell migration and invasion. Luciferase assays confirmed that miR-613 directly bound to the 3′ untranslated region of VEGFA, and western blotting showed that miR-613 suppressed the expression of VEGFA at the protein levels. This study indicated that miR-613 negatively regulates VEGFA and inhibits proliferation and invasion of breast cancer cell lines. Thus, miR-613 may represent a potential therapeutic molecule for breast cancer intervention.

Efficacy of ALK5 inhibition in myelofibrosis

Science.gov (United States)

Zhao, Wanke; Ho, Wanting Tina; Han, Ying; Murdun, Cem; Mailloux, Adam W.; Zhang, Ling; Wang, Xuefeng; Budhathoki, Anjali; Pradhan, Kith; Rapaport, Franck; Wang, Huaquan; Shao, Zonghong; Ren, Xiubao; Steidl, Ulrich; Levine, Ross L.; Zhao, Zhizhuang Joe; Verma, Amit; Epling-Burnette, Pearlie K.

2017-01-01

Myelofibrosis (MF) is a bone marrow disorder characterized by clonal myeloproliferation, aberrant cytokine production, extramedullary hematopoiesis, and bone marrow fibrosis. Although somatic mutations in JAK2, MPL, and CALR have been identified in the pathogenesis of these diseases, inhibitors of the Jak2 pathway have not demonstrated efficacy in ameliorating MF in patients. TGF-β family members are profibrotic cytokines and we observed significant TGF-β1 isoform overexpression in a large cohort of primary MF patient samples. Significant overexpression of TGF-β1 was also observed in murine clonal MPLW515L megakaryocytic cells. TGF-β1 stimulated the deposition of excessive collagen by mesenchymal stromal cells (MSCs) by activating the TGF-β receptor I kinase (ALK5)/Smad3 pathway. MSCs derived from MPLW515L mice demonstrated sustained overproduction of both collagen I and collagen III, effects that were abrogated by ALK5 inhibition in vitro and in vivo. Importantly, use of galunisertib, a clinically active ALK5 inhibitor, significantly improved MF in both MPLW515L and JAK2V617F mouse models. These data demonstrate the role of malignant hematopoietic stem cell (HSC)/TGF-β/MSC axis in the pathogenesis of MF, and provide a preclinical rationale for ALK5 blockade as a therapeutic strategy in MF. PMID:28405618

Inhibition of RAS in diabetic nephropathy

Directory of Open Access Journals (Sweden)

Yacoub R

2015-04-01

Full Text Available Rabi Yacoub, Kirk N Campbell Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, USA Abstract: Diabetic kidney disease (DKD is a progressive proteinuric renal disorder in patients with type 1 or type 2 diabetes mellitus. It is a common cause of end-stage kidney disease worldwide, particularly in developed countries. Therapeutic targeting of the renin–angiotensin system (RAS is the most validated clinical strategy for slowing disease progression. DKD is paradoxically a low systematic renin state with an increased intrarenal RAS activity implicated in its pathogenesis. Angiotensin II (AngII, the main peptide of RAS, is not only a vasoactive peptide but functions as a growth factor, activating interstitial fibroblasts and mesangial and tubular cells, while promoting the synthesis of extracellular matrix proteins. AngII also promotes podocyte injury through increased calcium influx and the generation of reactive oxygen species. Blockade of the RAS using either angiotensin converting enzyme inhibitors, or angiotensin receptor blockers can attenuate progressive glomerulosclerosis in animal models, and slows disease progression in humans with DKD. In this review, we summarize the role of intrarenal RAS activation in the pathogenesis and progression of DKD and the rationale for RAS inhibition in this population. Keywords: renin–angiotensin system, diabetic kidney disease, angiotensin II, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers

[Anatomy and pathogenesis of diverticular disease].

Science.gov (United States)

Wedel, T; Böttner, M

2014-04-01

Although diverticular disease is one of the most frequent gastrointestinal disorders the pathogenesis is not yet sufficiently clarified. The aim is to define the anatomy and pathogenesis of diverticular disease considering the risk factors and description of structural and functional alterations of the bowel wall. This article gives an appraisal of the literature, presentation and evaluation of classical etiological factors, analysis and discussion of novel pathogenetic concepts. Colonic diverticulosis is defined as an acquired out-pouching of multiple and initially asymptomatic pseudodiverticula through muscular gaps in the colon wall. Diverticular disease is characterized by diverticular bleeding and/or inflammatory processes (diverticulitis) with corresponding complications (e.g. abscess formation, fistula, covered and open perforation, peritonitis and stenosis). Risk factors for diverticular disease include increasing age, genetic predisposition, congenital connective tissue diseases, low fiber diet, high meat consumption and pronounced overweight. Alterations of connective tissue cause a weakening of preformed exit sites of diverticula and rigidity of the bowel wall with reduced flexibility. It is assumed that intestinal innervation disorders and structural alterations of the musculature induce abnormal contractile patterns with increased intraluminal pressure, thereby promoting the development of diverticula. Moreover, an increased release of pain-mediating neurotransmitters is considered to be responsible for persistent pain in chronic diverticular disease. According to the present data the pathogenesis of diverticular disease cannot be attributed to a single factor but should be considered as a multifactorial event.

Understanding Anaplasmataceae pathogenesis using ‘Omics’ approaches

Directory of Open Access Journals (Sweden)

Ludovic ePruneau

2014-07-01

Full Text Available This paper examines how Omics approaches improve our understanding of Anaplasmataceae pathogenesis, through a global and integrative strategy to identify genes and proteins involved in biochemical pathways key for pathogen-host-vector interactions.The Anaplasmataceae family comprises obligate intracellular bacteria mainly transmitted by arthropods. These bacteria are responsible for major human and animal endemic and emerging infectious diseases with important economic and public health impacts. In order to improve disease control strategies, it is essential to better understand their pathogenesis. Our work focused on four Anaplasmataceae, which cause important animal, human and zoonotic diseases: Anaplasma marginale, A. phagocytophilum, Ehrlichia chaffeensis and E. ruminantium. Wolbachia spp. an endosymbiont of arthropods was also included in this review as a model of a non-pathogenic Anaplasmataceae.A gap analysis on Omics approaches on Anaplasmataceae was performed, which highlighted a lack of studies on the genes and proteins involved in the infection of hosts and vectors. Furthermore, most of the studies have been done on the pathogen itself, mainly on infectious free-living forms and rarely on intracellular forms. In order to perform a transcriptomic analysis of the intracellular stage of development, researchers developed methods to enrich bacterial transcripts from infected cells. These methods are described in this paper. Bacterial genes encoding outer membrane proteins, post-translational modifications, eukaryotic repeated motif proteins, proteins involved in osmotic and oxidative stress and hypothetical proteins have been identified to play a key role in Anaplasmataceae pathogenesis. Further investigations on the function of these outer membrane proteins and hypothetical proteins will be essential to confirm their role in the pathogenesis. Our work underlines the need for further studies in this domain and on host and vector responses

Osmotin, a Pathogenesis-Related Protein

Czech Academy of Sciences Publication Activity Database

Viktorová, J.; Krásný, Lukáš; Kamlar, M.; Nováková, M.; Macková, M.; Macek, T.

2012-01-01

Roč. 13, č. 7 (2012), s. 672-681 ISSN 1389-2037 Grant - others:GA ČR(CZ) GAP501/11/1654; GA ČR(CZ) GA522/09/1693 Program:GA; GA Institutional support: RVO:61388971 Keywords : osmotin * pathogenesis-related proteins * antifungal activity Subject RIV: CE - Biochemistry Impact factor: 2.326, year: 2012

Obesity Exposure Across the Lifespan on Ovarian Cancer Pathogenesis

Science.gov (United States)

2015-08-01

exposure to the HFD or LFD, obese mice weighed significantly greater than lean mice (p=0.003, Table 1). There was no effect of HFD on non- fasted blood...AWARD NUMBER: W81XWH-13-1-0164 TITLE: Obesity Exposure Across the Lifespan on Ovarian Cancer Pathogenesis PRINCIPAL INVESTIGATOR: Victoria Bae...31 May 2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Obesity Exposure Across the Lifespan on Ovarian Cancer Pathogenesis 5b. GRANT NUMBER

T cell-dependence of Lassa fever pathogenesis.

Directory of Open Access Journals (Sweden)

Lukas Flatz

2010-03-01

Full Text Available Lassa virus (LASV, the causative agent of Lassa fever (LF, is endemic in West Africa, accounting for substantial morbidity and mortality. In spite of ongoing research efforts, LF pathogenesis and mechanisms of LASV immune control remain poorly understood. While normal laboratory mice are resistant to LASV, we report that mice expressing humanized instead of murine MHC class I (MHC-I failed to control LASV infection and develop severe LF. Infection of MHC-I knockout mice confirmed a key role for MHC-I-restricted T cell responses in controlling LASV. Intriguingly we found that T cell depletion in LASV-infected HHD mice prevented disease, irrespective of high-level viremia. Widespread activation of monocyte/macrophage lineage cells, manifest through inducible NO synthase expression, and elevated IL-12p40 serum levels indicated a systemic inflammatory condition. The absence of extensive monocyte/macrophage activation in T cell-depleted mice suggested that T cell responses contribute to deleterious innate inflammatory reactions and LF pathogenesis. Our observations in mice indicate a dual role for T cells, not only protecting from LASV, but also enhancing LF pathogenesis. The possibility of T cell-driven enhancement and immunopathogenesis should be given consideration in future LF vaccine development.

Eosinophils in vasculitis: characteristics and roles in pathogenesis

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Khoury, Paneez; Grayson, Peter C.; Klion, Amy D.

2016-01-01

Eosinophils are multifunctional granular leukocytes that are implicated in the pathogenesis of a wide variety of disorders, including asthma, helminth infection, and rare hypereosinophilic syndromes. Although peripheral and tissue eosinophilia can be a feature of many types of small-vessel and medium-vessel vasculitis, the role of eosinophils has been best studied in eosinophilic granulomatosis with polyangiitis (EGPA), where eosinophils are a characteristic finding in all three clinical stages of the disorder. Whereas numerous studies have demonstrated an association between the presence of eosinophils and markers of eosinophil activation in the blood and tissues of patients with EGPA, the precise role of eosinophils in disease pathogenesis has been difficult to ascertain owing to the complexity of the disease process. In this regard, results of clinical trials using novel agents that specifically target eosinophils are providing the first direct evidence of a central role of eosinophils in EGPA. This Review focuses on the aspects of eosinophil biology most relevant to the pathogenesis of vasculitis and provides an update of current knowledge regarding the role of eosinophils in EGPA and other vasculitides. PMID:25003763

ω-Hydroxyemodin Limits Staphylococcus aureus Quorum Sensing-Mediated Pathogenesis and Inflammation

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Daly, Seth M.; Elmore, Bradley O.; Kavanaugh, Jeffrey S.; Triplett, Kathleen D.; Figueroa, Mario; Raja, Huzefa A.; El-Elimat, Tamam; Crosby, Heidi A.; Femling, Jon K.; Cech, Nadja B.; Horswill, Alexander R.; Oberlies, Nicholas H.

2015-01-01

Antibiotic-resistant pathogens are a global health threat. Small molecules that inhibit bacterial virulence have been suggested as alternatives or adjuncts to conventional antibiotics, as they may limit pathogenesis and increase bacterial susceptibility to host killing. Staphylococcus aureus is a major cause of invasive skin and soft tissue infections (SSTIs) in both the hospital and community settings, and it is also becoming increasingly antibiotic resistant. Quorum sensing (QS) mediated by the accessory gene regulator (agr) controls virulence factor production essential for causing SSTIs. We recently identified ω-hydroxyemodin (OHM), a polyhydroxyanthraquinone isolated from solid-phase cultures of Penicillium restrictum, as a suppressor of QS and a compound sought for the further characterization of the mechanism of action. At concentrations that are nontoxic to eukaryotic cells and subinhibitory to bacterial growth, OHM prevented agr signaling by all four S. aureus agr alleles. OHM inhibited QS by direct binding to AgrA, the response regulator encoded by the agr operon, preventing the interaction of AgrA with the agr P2 promoter. Importantly, OHM was efficacious in a mouse model of S. aureus SSTI. Decreased dermonecrosis with OHM treatment was associated with enhanced bacterial clearance and reductions in inflammatory cytokine transcription and expression at the site of infection. Furthermore, OHM treatment enhanced the immune cell killing of S. aureus in vitro in an agr-dependent manner. These data suggest that bacterial disarmament through the suppression of S. aureus QS may bolster the host innate immune response and limit inflammation. PMID:25645827

Morbillivirus Experimental Animal Models: Measles Virus Pathogenesis Insights from Canine Distemper Virus.

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da Fontoura Budaszewski, Renata; von Messling, Veronika

2016-10-11

Morbilliviruses share considerable structural and functional similarities. Even though disease severity varies among the respective host species, the underlying pathogenesis and the clinical signs are comparable. Thus, insights gained with one morbillivirus often apply to the other members of the genus. Since the Canine distemper virus (CDV) causes severe and often lethal disease in dogs and ferrets, it is an attractive model to characterize morbillivirus pathogenesis mechanisms and to evaluate the efficacy of new prophylactic and therapeutic approaches. This review compares the cellular tropism, pathogenesis, mechanisms of persistence and immunosuppression of the Measles virus (MeV) and CDV. It then summarizes the contributions made by studies on the CDV in dogs and ferrets to our understanding of MeV pathogenesis and to vaccine and drugs development.

Emmprin and KSHV: new partners in viral cancer pathogenesis.

Science.gov (United States)

Dai, Lu; Bai, Lihua; Lu, Ying; Xu, Zengguang; Reiss, Krys; Del Valle, Luis; Kaleeba, Johnan; Toole, Bryan P; Parsons, Chris; Qin, Zhiqiang

2013-09-01

Emmprin (CD147; basigin) is a multifunctional glycoprotein expressed at higher levels by cancer cells and stromal cells in the tumor microenvironment. Through direct effects within tumor cells and promotion of tumor-stroma interactions, emmprin participates in induction of tumor cell invasiveness, angiogenesis, metastasis and chemoresistance. Although its contribution to cancer progression has been widely studied, the role of emmprin in viral oncogenesis still remains largely unclear, and only a small body of available literature implicates emmprin-associated mechanisms in viral pathogenesis and tumorigenesis. We summarize these data in this review, focusing on the role of emmprin in pathogenesis associated with the Kaposi sarcoma-associated herpesvirus (KSHV), a common etiology for cancers arising in the setting of immune suppression. We also discuss future directions for mechanistic studies exploring roles for emmprin in viral cancer pathogenesis. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The Paradox of Feline Coronavirus Pathogenesis: A Review

Directory of Open Access Journals (Sweden)

Luciana Wanderley Myrrha

2011-01-01

Full Text Available Feline coronavirus (FCoV is an enveloped single-stranded RNA virus, of the family Coronaviridae and the order Nidovirales. FCoV is an important pathogen of wild and domestic cats and can cause a mild or apparently symptomless enteric infection, especially in kittens. FCoV is also associated with a lethal, systemic disease known as feline infectious peritonitis (FIP. Although the precise cause of FIP pathogenesis remains unclear, some hypotheses have been suggested. In this review we present results from different FCoV studies and attempt to elucidate existing theories on the pathogenesis of FCoV infection.

Ebola haemorrhagic fever virus: pathogenesis, immune responses, potential prevention.

Science.gov (United States)

Marcinkiewicz, Janusz; Bryniarski, Krzysztof; Nazimek, Katarzyna

2014-01-01

Ebola zoonotic RNA filovirus represents human most virulent and lethal pathogens, which induces acute hemorrhagic fever and death within few days in a range of 60-90% of symptomatic individuals. Last outbreak in 2014 in West Africa caused panic that Ebola epidemic can be spread to other continents. Number of deaths in late December reached almost 8,000 individuals out of more than 20,000 symptomatic patients. It seems that only a coordinated international response could counteract the further spread of Ebola. Major innate immunity mechanisms against Ebola are associated with the production of interferons, that are inhibited by viral proteins. Activation of host NK cells was recognized as a leading immune function responsible for recovery of infected people. Uncontrolled cell infection by Ebola leads to an impairment of immunity with cytokine storm, coagulopathy, systemic bleeding, multi-organ failure and death. Tested prevention strategies to induce antiviral immunity include: i. recombinant virus formulations (vaccines); ii. cocktail of monoclonal antibodies (serotherapy); iii. alternative RNA-interference-based antiviral methods. Maintaining the highest standards of aseptic and antiseptic precautions is equally important. Present brief review summarizes a current knowledge concerning pathogenesis of Ebola hemorrhagic disease and the virus interaction with the immune system and discusses recent advances in prevention of Ebola infection by vaccination and serotherapy.

Tryptophan-induced pathogenesis of breast cancer

African Journals Online (AJOL)

Aims: To investigate the pathogenesis of breast cancer through targeted metabolomics of amino acids ... Furthermore, the biological function of tryptophan was determined through determining the influence ... profiling all the small molecules in the biosamples (e.g., .... is a promising therapeutic agent for pancreatic cancer7.

Mid-Atlantic Microbial Pathogenesis Meeting

Science.gov (United States)

2005-12-01

rheumatic fever, yet little is understood about the regulation of streptococcal genes involved in disease processes and survival in the host. Genome...of brucellosis, a disease that is characterized by abortion and infertility in ruminant animals and undulant fever in humans. In the natural hosts...were presented at this session. 15. SUBJECT TERMS bacteria, pathogenesis, microbiology, virulence, disease 16. SECURITY CLASSIFICATION OF: 17

Biology and pathogenesis of Acanthamoeba

OpenAIRE

Siddiqui, Ruqaiyyah; Khan, Naveed Ahmed

2012-01-01

Abstract Acanthamoeba is a free-living protist pathogen, capable of causing a blinding keratitis and fatal granulomatous encephalitis. The factors that contribute to Acanthamoeba infections include parasite biology, genetic diversity, environmental spread and host susceptibility, and are highlighted together with potential therapeutic and preventative measures. The use of Acanthamoeba in the study of cellular differentiation mechanisms, motility and phagocytosis, bacterial pathogenesis and ev...

Genistein inhibited ammonia induced astrocyte swelling by inhibiting NF-κB activation-mediated nitric oxide formation.

Science.gov (United States)

Dai, Hongliang; Jia, Guizhi; Wang, Wei; Liang, Chunguang; Han, Siyu; Chu, Minghui; Mei, Xifan

2017-06-01

Our previous study has indicated the involvement of epidermal growth factor receptor (EGFR) transactivation in ammonia-induced astrocyte swelling, which represents a major pathogenesis of brain edema in hepatic encephalopathy. In this study, we examined the effect of genistein, a naturally occurred broad-spectrum protein tyrosine kinase (PTK) inhibitor, on ammonia-induced cell swelling. We found that genistein pretreatment significantly prevented ammonia-induced astrocyte swelling. Mechanistically, ammonia triggered EGFR/extracellular signal-regulated kinase (ERK) association and subsequent ERK phosphorylation were alleviated by genistein pretreatment. Moreover, ammonia-induced NF-κB nuclear location, iNOS expression, and consequent NO production were all prevented by AG1478 and genistein pretreatment. This study suggested that genistein could alleviate ammonia-induced astrocyte swelling, which may be, at least partly, related to its PTK-inhibiting activity and repression of NF-κB mediated iNOS-derived NO accumulation.

[Current concepts in pathogenesis of age-related macular degeneration].

Science.gov (United States)

Kubicka-Trząska, Agnieszka; Karska-Basta, Izabella; Romanowska-Dixon, Bożena

2014-01-01

Age-related macular degeneration is the leading cause of central blindness in elderly population of the western world. The pathogenesis of this disease, likely multifactorial, is not well known, although a number of theories have been put forward, including oxidative stress, genetic interactions, hemodynamic imbalance, immune and inflammatory processes. The understanding of age-related macular degeneration pathogenesis will give rise to new approaches in prevention and treatment of the early and late stages of both atrophic and neovascular age-related macular degeneration.

Studies on the molecular pathogenesis of radiation pulmonary fibrosis

International Nuclear Information System (INIS)

Li Yang

2003-01-01

Radiation pulmonary fibrosis (RPF) is a frequent side effect of thoracic radiotherapy for breast neoplasm and total body irradiation before bone marrow transplantation. Studies on its pathogenesis have arrived at molecular level. Many cytokines, adhesion molecules and vasoactive substances all play important role in the course of RPF. Moreover, there exists genetic loci that has relation with RPF. Furthermore, studies on the molecular pathogenesis of RPF have provided new ideas and new measures for the precaution and therapy of RPF

The population of TeV pulsar wind nebulae in the H.E.S.S. Galactic Plane Survey

Science.gov (United States)

H. E. S. S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Andersson, T.; Angüner, E. O.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Bulik, T.; Capasso, M.; Carr, J.; Carrigan, S.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chalme-Calvet, R.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Chrétien, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Couturier, C.; Cui, Y.; Davids, I. D.; Degrange, B.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'C.; Dubus, G.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hadasch, D.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hillert, A.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holler, M.; Horns, D.; Ivascenko, A.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katz, U.; Kerszberg, D.; Khélifi, B.; Kieffer, M.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krayzel, F.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; de Naurois, M.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Öttl, S.; Ohm, S.; de Oña Wilhelmi, E.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Paz Arribas, M.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Rieger, F.; Romoli, C.; Rosier-Lees, S.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stinzing, F.; Stycz, K.; Sushch, I.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tuffs, R.; Uchiyama, Y.; Valerius, K.; van der Walt, D. J.; van Eldik, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Żywucka, N.

2018-04-01

The nine-year H.E.S.S. Galactic Plane Survey (HGPS) has yielded the most uniform observation scan of the inner Milky Way in the TeV gamma-ray band to date. The sky maps and source catalogue of the HGPS allow for a systematic study of the population of TeV pulsar wind nebulae found throughout the last decade. To investigate the nature and evolution of pulsar wind nebulae, for the first time we also present several upper limits for regions around pulsars without a detected TeV wind nebula. Our data exhibit a correlation of TeV surface brightness with pulsar spin-down power Ė. This seems to be caused both by an increase of extension with decreasing Ė, and hence with time, compatible with a power law RPWN(Ė) Ė-0.65±0.20, and by a mild decrease of TeV gamma-ray luminosity with decreasing Ė, compatible with L1-10 TeV Ė0.59±0.21. We also find that the offsets of pulsars with respect to the wind nebula centre with ages around 10 kyr are frequently larger than can be plausibly explained by pulsar proper motion and could be due to an asymmetric environment. In the present data, it seems that a large pulsar offset is correlated with a high apparent TeV efficiency L1-10 TeV/Ė. In addition to 14 HGPS sources considered firmly identified pulsar wind nebulae and 5 additional pulsar wind nebulae taken from literature, we find 10 HGPS sources that are likely TeV pulsar wind nebula candidates. Using a model that subsumes the present common understanding of the very high-energy radiative evolution of pulsar wind nebulae, we find that the trends and variations of the TeV observables and limits can be reproduced to a good level, drawing a consistent picture of present-day TeV data and theory.

Pathogenesis of varicelloviruses in primates.

Science.gov (United States)

Ouwendijk, Werner J D; Verjans, Georges M G M

2015-01-01

Varicelloviruses in primates comprise the prototypic human varicella-zoster virus (VZV) and its non-human primate homologue, simian varicella virus (SVV). Both viruses cause varicella as a primary infection, establish latency in ganglionic neurons and reactivate later in life to cause herpes zoster in their respective hosts. VZV is endemic worldwide and, although varicella is usually a benign disease in childhood, VZV reactivation is a significant cause of neurological disease in the elderly and in immunocompromised individuals. The pathogenesis of VZV infection remains ill-defined, mostly due to the species restriction of VZV that impedes studies in experimental animal models. SVV infection of non-human primates parallels virological, clinical, pathological and immunological features of human VZV infection, thereby providing an excellent model to study the pathogenesis of varicella and herpes zoster in its natural host. In this review, we discuss recent studies that provided novel insight in both the virus and host factors involved in the three elementary stages of Varicellovirus infection in primates: primary infection, latency and reactivation. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Helicobacter pylori virulence and cancer pathogenesis.

Science.gov (United States)

Yamaoka, Yoshio; Graham, David Y

2014-06-01

Helicobacter pylori is human gastric pathogen that causes chronic and progressive gastric mucosal inflammation and is responsible for the gastric inflammation-associated diseases, gastric cancer and peptic ulcer disease. Specific outcomes reflect the interplay between host-, environmental- and bacterial-specific factors. Progress in understanding putative virulence factors in disease pathogenesis has been limited and many false leads have consumed scarce resources. Few in vitro-in vivo correlations or translational applications have proved clinically relevant. Reported virulence factor-related outcomes reflect differences in relative risk of disease rather than specificity for any specific outcome. Studies of individual virulence factor associations have provided conflicting results. Since virulence factors are linked, studies of groups of putative virulence factors are needed to provide clinically useful information. Here, the authors discuss the progress made in understanding the role of H. pylori virulence factors CagA, vacuolating cytotoxin, OipA and DupA in disease pathogenesis and provide suggestions for future studies.

Anti-diabetes drug pioglitazone ameliorates synaptic defects in AD transgenic mice by inhibiting cyclin-dependent kinase5 activity.

Directory of Open Access Journals (Sweden)

Jinan Chen

Full Text Available Cyclin-dependent kinase 5 (Cdk5 is a serine/threonine kinase that is activated by the neuron specific activators p35/p39 and plays many important roles in neuronal development. However, aberrant activation of Cdk5 is believed to be associated with the pathogenesis of several neurodegenerative diseases, including Alzheimer's disease (AD and Parkinson's disease (PD. Here in the present study, enhanced Cdk5 activity was observed in mouse models of AD; whereas soluble amyloid-β oligomers (Aβ, which contribute to synaptic failures during AD pathogenesis, induced Cdk5 hyperactivation in cultured hippocampal neurons. Inhibition of Cdk5 activity by pharmacological or genetic approaches reversed dendritic spine loss caused by soluble amyloid-β oligomers (Aβ treatment. Interestingly, we found that the anti-diabetes drug pioglitazone could inhibit Cdk5 activity by decreasing p35 protein level. More importantly, pioglitazone treatment corrected long-term potentiation (LTP deficit caused by Aβ exposure in cultured slices and pioglitazone administration rescued impaired LTP and spatial memory in AD mouse models. Taken together, our study describes an unanticipated role of pioglitazone in alleviating AD and reveals a potential therapeutic drug for AD curing.

Current understanding in pathogenesis of atopic dermatitis

Directory of Open Access Journals (Sweden)

Tess McPherson

2016-01-01

Full Text Available There have been advances in our understanding of the complex pathogenesis of atopic eczema over the past few decades. This article examines the multiple factors which are implicated in this process.

Pathogenesis of Abdominal Aortic Aneurysms: Role of Nicotine and Nicotinic Acetylcholine Receptors

Directory of Open Access Journals (Sweden)

Zong-Zhuang Li

2012-01-01

Full Text Available Inflammation, proteolysis, smooth muscle cell apoptosis, and angiogenesis have been implicated in the pathogenesis of abdominal aortic aneurysms (AAAs, although the well-defined initiating mechanism is not fully understood. Matrix metalloproteinases (MMPs such as MMP-2 and -9 and other proteinases degrading elastin and extracellular matrix are the critical pathogenesis of AAAs. Among the risk factors of AAAs, cigarette smoking is an irrefutable one. Cigarette smoke is practically involved in various aspects of the AAA pathogenesis. Nicotine, a major alkaloid in tobacco leaves and a primary component in cigarette smoke, can stimulate the MMPs expression by vascular SMCs, endothelial cells, and inflammatory cells in vascular wall and induce angiogenesis in the aneurysmal tissues. However, for the inflammatory and apoptotic processes in the pathogenesis of AAAs, nicotine seems to be moving in just the opposite direction. Additionally, the effects of nicotine are probably dose dependent or associated with the exposure duration and may be partly exerted by its receptors—nicotinic acetylcholine receptors (nAChRs. In this paper, we will mainly discuss the pathogenesis of AAAs involving inflammation, proteolysis, smooth muscle cell apoptosis and angiogenesis, and the roles of nicotine and nAChRs.

The pathogenesis of progressive multifocal leukoencephalopathy.

Science.gov (United States)

Berger, Joseph R; Khalili, Kamel

2011-12-01

Interest in pathogenesis of progressive multifocal leukoencephalopathy (PML) followed the observation of the high risk for the disease in HIV infection and the recent observation of an association with a variety of newer therapeutic modalities, e.g., natalizumab, an α4β1 integrin inhibitor, and efalizumab, an anti-CD11a monoclonal antibody. Any hypothesis of PML pathogenesis must account for a number of facts. Firstly, the causative agent JC virus is ubiquitously present, yet only a vanishingly small number of infected persons develop the disease. Secondly, disorders of cell-mediated immunity increase the risk of the disease, particularly HIV infection. Impaired innate immunity is not a risk for PML, and antibodies against JC virus are not protective. Thirdly, a latent period of several months appears necessary following the administration of natalizumab and efalizumab before PML develops. Fourthly, restoration of the immune system can arrest the PML. It is possible that infection with JC virus occurs with a form of the virus shed in the urine of as many as 40% of all adults and present in sewage worldwide. Once acquired, perhaps through an oropharyngeal route, it may replicate and disseminate. A neurotropic form of JC virus that replicates in glial tissues causes PML when immunosurveillance is impaired. There are many unanswered questions with respect to PML pathogenesis. How is virus acquired? What tissues are infected? What is the origin of the neurotropic form? When does virus enter brain? What is the role of central nervous system immunosurveillance? The lack of an animal model has made answering these questions challenging. © Discovery Medicine

Pharmacological inhibition of feline immunodeficiency virus (FIV).

Science.gov (United States)

Mohammadi, Hakimeh; Bienzle, Dorothee

2012-05-01

Feline immunodeficiency virus (FIV) is a member of the retroviridae family of viruses and causes an acquired immunodeficiency syndrome (AIDS) in domestic and non-domestic cats worldwide. Genome organization of FIV and clinical characteristics of the disease caused by the virus are similar to those of human immunodeficiency virus (HIV). Both viruses infect T lymphocytes, monocytes and macrophages, and their replication cycle in infected cells is analogous. Due to marked similarity in genomic organization, virus structure, virus replication and disease pathogenesis of FIV and HIV, infection of cats with FIV is a useful tool to study and develop novel drugs and vaccines for HIV. Anti-retroviral drugs studied extensively in HIV infection have targeted different steps of the virus replication cycle: (1) inhibition of virus entry into susceptible cells at the level of attachment to host cell surface receptors and co-receptors; (2) inhibition of fusion of the virus membrane with the cell membrane; (3) blockade of reverse transcription of viral genomic RNA; (4) interruption of nuclear translocation and viral DNA integration into host genomes; (5) prevention of viral transcript processing and nuclear export; and (6) inhibition of virion assembly and maturation. Despite much success of anti-retroviral therapy slowing disease progression in people, similar therapy has not been thoroughly investigated in cats. In this article we review current pharmacological approaches and novel targets for anti-lentiviral therapy, and critically assess potentially suitable applications against FIV infection in cats.

Antisense locked nucleic acids targeting agrA inhibit quorum sensing and pathogenesis of community-associated methicillin-resistant Staphylococcus aureus.

Science.gov (United States)

Da, F; Yao, L; Su, Z; Hou, Z; Li, Z; Xue, X; Meng, J; Luo, X

2017-01-01

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is commonly associated with nonnosocomial skin and soft tissue infections due to its virulence, which is mainly controlled by the accessory gene regulator (agr) quorum sensing (QS) system. In this study (KFF) 3 K peptide-conjugated locked nucleic acids (PLNAs) targeting agrA mRNA were developed to inhibit agr activity and arrest the pathogenicity of CA-MRSA. Two PLNAs were designed, and synthesized, after predicting the secondary structure of agrA mRNA. The influence on bacterial growth was tested using a growth curve assay. RT-qPCR, haemolysis assay, lactate dehydrogenase release assay and chemotaxis assay were used to evaluate the effects of the PLNAs on inhibiting agr QS. A mouse skin infection model was employed to test the protective effect of the PLNAs in vivo. None of the PLNAs were found to be bacteriostatic or bactericidal in vitro. However, one PLNA, PLNA34, showed strong ability to suppress expression of agrA and the effector molecule RNAIII in USA300 LAC strain. Furthermore, PLNA34 inhibited the expression of virulence genes that are upregulated by agr, including hla, psmα, psmβ and pvl. The haemolytic activity of the supernatants from PLNA34-treated bacteria was also dramatically reduced, as well as the capacity to lyse and recruit neutrophils. Moreover, PLNA34 showed high levels of protection in the CA-MRSA mouse skin infection model. The anti-agrA PLNA34 can effectively inhibit the agr QS and suppress CA-MRSA pathogenicity. agrA is a promising target for the development of antisense oligonucleotides to block agr QS. Journal of Applied Microbiology © 2016 The Society for Applied Microbiology.

The role of clusterin in Alzheimer's disease: pathways, pathogenesis, and therapy.

Science.gov (United States)

Yu, Jin-Tai; Tan, Lan

2012-04-01

Genetic variation in clusterin gene, also known as apolipoprotein J, has been associated with Alzheimer's disease (AD) through replicated genome-wide studies, and plasma clusterin levels are associated with brain atrophy, baseline prevalence and severity, and rapid clinical progression in patients with AD, highlighting the importance of clusterin in AD pathogenesis. Emerging data suggest that clusterin contributes to AD through various pathways, including amyloid-β aggregation and clearance, lipid metabolism, neuroinflammation, and neuronal cell cycle control and apoptosis. Moreover, epigenetic regulation of the clusterin expression also seems to play an important role in the pathogenesis of AD. Emerging knowledge of the contribution of clusterin to the pathogenesis of AD presents new opportunities for AD therapy.

[Establishing Individualized Medicine for Intractable Cancer Based on Clinical Molecular Pathogenesis].

Science.gov (United States)

Jono, Hirofumi

2018-01-01

　Although cancer treatment has dramatically improved with the development of molecular-targeted agents over the past decade, identifying eligible patients and predicting the therapeutic effects remain a major challenge. Because intratumoral heterogeneity represents genetic and molecular differences affecting patients' responses to these therapeutic agents, establishing individualized medicine based on precise molecular pathological analysis of tumors is urgently required. This review focuses on the pathogenesis of oral squamous cell carcinoma (OSCC), a common head and neck neoplasm, and introduces our approaches toward developing novel anticancer therapies particularly based on clinical molecular pathogenesis. Deeper understanding of more precise molecular pathogenesis in clinical settings may open up novel strategies for establishing individualized medicine for OSCC.

DMPD: Role of Toll-like receptor responses for sepsis pathogenesis. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available 18086373 Role of Toll-like receptor responses for sepsis pathogenesis. Weighardt H,... of Toll-like receptor responses for sepsis pathogenesis. PubmedID 18086373 Title Role of Toll-like receptor... responses for sepsis pathogenesis. Authors Weighardt H, Holzmann B. Publication

Progeria 101/FAQ

Science.gov (United States)

... Progeria, but also may shed light on the phenomenon of aging and cardiovascular disease.” v “Recurrent de ... Statistics Is Progeria passed down from parent to child? HGPS is not usually passed down in families. ...

Molecular Pathogenesis of Neuromyelitis Optica

Science.gov (United States)

Bukhari, Wajih; Barnett, Michael H; Prain, Kerri; Broadley, Simon A

2012-01-01

Neuromyelitis optica (NMO) is a rare autoimmune disorder, distinct from multiple sclerosis, causing inflammatory lesions in the optic nerves and spinal cord. An autoantibody (NMO IgG) against aquaporin-4 (AQP4), a water channel expressed on astrocytes is thought to be causative. Peripheral production of the antibody is triggered by an unknown process in genetically susceptible individuals. Anti-AQP4 antibody enters the central nervous system (CNS) when the blood brain barrier is made permeable and has high affinity for orthogonal array particles of AQP4. Like other autoimmune diseases, Th17 cells and their effector cytokines (such as interleukin 6) have been implicated in pathogenesis. AQP4 expressing peripheral organs are not affected by NMO IgG, but the antibody causes extensive astrocytic loss in specific regions of the CNS through complement mediated cytotoxicity. Demyelination occurs during the inflammatory process and is probably secondary to oligodendrocyte apoptosis subsequent to loss of trophic support from astrocytes. Ultimately, extensive axonal injury leads to severe disability. Despite rapid advances in the understanding of NMO pathogenesis, unanswered questions remain, particularly with regards to disease mechanisms in NMO IgG seronegative cases. Increasing knowledge of the molecular pathology is leading to improved treatment strategies. PMID:23202933

Pathogenesis of Focal Segmental Glomerulosclerosis

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Beom Jin Lim

2016-11-01

Full Text Available Focal segmental glomerulosclerosis (FSGS is characterized by focal and segmental obliteration of glomerular capillary tufts with increased matrix. FSGS is classified as collapsing, tip, cellular, perihilar and not otherwise specified variants according to the location and character of the sclerotic lesion. Primary or idiopathic FSGS is considered to be related to podocyte injury, and the pathogenesis of podocyte injury has been actively investigated. Several circulating factors affecting podocyte permeability barrier have been proposed, but not proven to cause FSGS. FSGS may also be caused by genetic alterations. These genes are mainly those regulating slit diaphragm structure, actin cytoskeleton of podocytes, and foot process structure. The mode of inheritance and age of onset are different according to the gene involved. Recently, the role of parietal epithelial cells (PECs has been highlighted. Podocytes and PECs have common mesenchymal progenitors, therefore, PECs could be a source of podocyte repopulation after podocyte injury. Activated PECs migrate along adhesion to the glomerular tuft and may also contribute to the progression of sclerosis. Markers of activated PECs, including CD44, could be used to distinguish FSGS from minimal change disease. The pathogenesis of FSGS is very complex; however, understanding basic mechanisms of podocyte injury is important not only for basic research, but also for daily diagnostic pathology practice.

Stress Hormone Cortisol Enhances Bcl2 Like-12 Expression to Inhibit p53 in Hepatocellular Carcinoma Cells.

Science.gov (United States)

Wu, Weizhong; Liu, Sanguang; Liang, Yunfei; Zhou, Zegao; Bian, Wei; Liu, Xueqing

2017-12-01

The pathogenesis of hepatocellular carcinoma (HC) is unclear. It is suggested that psychological stress associates with the pathogenesis of liver cancer. Bcl2-like protein 12 (Bcl2L12) suppresses p53 protein. This study tests a hypothesis that the major stress hormone, cortisol, inhibits the expression of p53 in HC cells (HCC) via up regulating the expression of Bcl2L12. Peripheral blood samples were collected from patients with HC to be analyzed for the levels of cortisol. HCC were cultured to assess the role of cortisol in the regulation of the expression of Bcl2L12 and p53 in HCC. We observed that the serum cortisol levels were higher in HC patients. Expression of Bcl2L12 in HCC was correlated with serum cortisol. Cortisol enhanced the Bcl2L12 expression in HCC. Bcl2L12 binding to the TP53 promoter was correlated with p53 expression in HCC. Cortisol increased the Bcl2L12 expression in HCC to inhibit p53 expression. Stress hormone cortisol suppresses p53 in HCC via enhancing Bcl2L12 expression in HCC. The results suggest that cortisol may be a therapeutic target for the treatment of HC.

Pathogenesis of bovine spongiform encephalopathy in sheep

NARCIS (Netherlands)

Keulen, van L.J.M.; Vromans, M.E.W.; Dolstra, C.H.; Bossers, A.; Zijderveld, van F.G.

2008-01-01

The pathogenesis of bovine spongiform encephalopathy (BSE) in sheep was studied by immunohistochemical detection of scrapie-associated prion protein (PrPSc) in the gastrointestinal, lymphoid and neural tissues following oral inoculation with BSE brain homogenate. First accumulation of PrPSc was

ROLE OF MAGNESIUM IN HEADACHE PATHOGENESIS IN CHILDREN AND ADOLESCENTS

Directory of Open Access Journals (Sweden)

E. S. Akarachkova

2013-01-01

Full Text Available Article is dedicated to the problem of headache in children. This pathology is being found more frequently in pediatric and children’s neurologic practice. The authors examine headache pathogenesis from the position of magnesium deficiency. Analysis of results of the modern studies on magnesium deficiency and its correction in patients with headache indicates that magnesium metabolism may play an important role both in pathogenesis of different headache types and in its treatment and prevention.

Systematic approach to understanding the pathogenesis of systemic sclerosis.

Science.gov (United States)

Zuo, Xiaoxia; Zhang, Lihua; Luo, Hui; Li, Yisha; Zhu, Honglin

2017-10-01

Systemic sclerosis (SSc) is a complex heterogeneous autoimmune disease. Progressive organ fibrosis is a major contributor to SSc mortality. Despite extensive efforts, the underlying mechanism of SSc remains unclear. Efforts to understand the pathogenesis of SSc have included genomics, epigenetics, transcriptomic, proteomic and metabolomic studies in the last decade. This review focuses on recent studies in SSc research based on multi-omics. The combination of these technologies can help us understand the pathogenesis of SSc. This review aims to provide important information for disease identification, therapeutic targets and potential biomarkers. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Frontoethmoidal encephaloceles, a study of their pathogenesis

NARCIS (Netherlands)

Hoving, Eelco; Vermeij-Keers, C

1997-01-01

A prospective clinical study of 30 patients with frontoethmoidal encephaloceles was performed in order to find support for a proposed theory concerning its pathogenesis, based on a previously performed embryological study and relevant findings in the literature. According to this proposed theory the

Prion pathogenesis is unaltered in the absence of SIRPα-mediated "don't-eat-me" signaling.

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Mario Nuvolone

Full Text Available Prion diseases are neurodegenerative conditions caused by misfolding of the prion protein, leading to conspicuous neuronal loss and intense microgliosis. Recent experimental evidence point towards a protective role of microglia against prion-induced neurodegeneration, possibly through elimination of prion-containing apoptotic bodies. The molecular mechanisms by which microglia recognize and eliminate apoptotic cells in the context of prion diseases are poorly defined. Here we investigated the possible involvement of signal regulatory protein α (SIRPα, a key modulator of host cell phagocytosis; SIRPα is encoded by the Sirpa gene that is genetically linked to the prion gene Prnp. We found that Sirpa transcripts are highly enriched in microglia cells within the brain. However, Sirpa mRNA levels were essentially unaltered during the course of experimental prion disease despite upregulation of other microglia-enriched transcripts. To study the involvement of SIRPα in prion pathogenesis in vivo, mice expressing a truncated SIRPα protein unable to inhibit phagocytosis were inoculated with rodent-adapted scrapie prions of the 22L strain. Homozygous and heterozygous Sirpa mutants and wild-type mice experienced similar incubation times after inoculation with either of two doses of 22L prions. Moreover, the extent of neuronal loss, microgliosis and abnormal prion protein accumulation was not significantly affected by Sirpa genotypes. Collectively, these data indicate that SIRPα-mediated phagocytosis is not a major determinant in prion disease pathogenesis. It will be important to search for additional candidates mediating prion phagocytosis, as this mechanism may represent an important target of antiprion therapies.

The implication of neuroactive steroids in Tourette syndrome pathogenesis: a role for 5α-reductase?

Science.gov (United States)

Bortolato, Marco; Frau, Roberto; Godar, Sean C; Mosher, Laura J; Paba, Silvia; Marrosu, Francesco; Devoto, Paola

2013-01-01

Tourette syndrome (TS) is a neurodevelopmental disorder characterized by recurring motor and phonic tics. The pathogenesis of TS is thought to reflect dysregulations in the signaling of dopamine (DA) and other neurotransmitters, which lead to excitation/inhibition imbalances in cortico-striato-thalamocortical circuits. The causes of these deficits may reflect complex gene × environment × sex (G×E×S) interactions; indeed, the disorder is markedly predominant in males, with a male-to-female prevalence ratio of ~4:1. Converging lines of evidence point to neuroactive steroids as likely molecular candidates to account for GxExS interactions in TS. Building on these premises, our group has begun examining the possibility that alterations in the steroid biosynthetic process may be directly implicated in TS pathophysiology; in particular, our research has focused on 5α-reductase (5αR), the enzyme catalyzing the key rate-limiting step in the synthesis of pregnane and androstane neurosteroids. In clinical and preclinical studies, we found that 5αR inhibitors exerted marked anti-DAergic and tic-suppressing properties, suggesting a central role for this enzyme in TS pathogenesis. Based on these data, we hypothesize that enhancements in 5αR activity in early developmental stages may lead to an inappropriate activation of the “backdoor” pathway for androgen synthesis from adrenarche until the end of puberty. We predict that the ensuing imbalances in steroid homeostasis may impair the signaling of DA and other neurotransmitters, ultimately resulting in the facilitation of tics and other behavioral abnormalities in TS. PMID:23795653

Insights in the pathogenesis of Dobermann hepatitis

NARCIS (Netherlands)

Mandigers, Paulus Justinus Johannes

2005-01-01

The pathogenesis of Dobermann hepatitis has been under debate for several years. In this thesis two hypotheses were formulated and discussed. Hypothesis 1: In Dobermann dogs exists an autosomal genetic error in metabolism that leads to an abnormal copper metabolism which results in an increased

Polydatin (PD) inhibits IgE-mediated passive cutaneous anaphylaxis in mice by stabilizing mast cells through modulating Ca2+ mobilization

International Nuclear Information System (INIS)

Yuan, Meichun; Li, Jianjie; Lv, Jingzhang; Mo, Xucheng; Yang, Chengbin; Chen, Xiangdong; Liu, Zhigang; Liu, Jie

2012-01-01

Mast cells play a key role in the pathogenesis of asthma and are a promising target for therapeutic intervention in asthma. This study investigated the effects of polydatin (PD), a resveratrol glucoside, on mast cell degranulation upon cross-linking of the high-affinity IgE receptors (FcεRI), as well as the anti-allergic activity of PD in vivo. Herein, we demonstrated that PD treatment for 30 min suppressed FcεRI-mediated mast cell degranulation in a dose-dependent manner. Concomitantly, PD significantly decreased FcεRI-mediated Ca 2+ increase in mast cells. The suppressive effects of PD on FcεRI-mediated Ca 2+ increase were largely inhibited by using LaCl 3 to block the Ca 2+ release-activated Ca 2+ channels (CRACs). Furthermore, PD significantly inhibited Ca 2+ entry through CRACs evoked by thapsigargin (TG). Knocking down protein expression of Orai1, the pore-forming subunit of CRACs, significantly decreased PD suppression of FcεRI-induced intracellular Ca 2+ influx and mast cell degranulation. In a mouse model of mast cell-dependent passive cutaneous anaphylaxis (PCA), in vivo PD administration suppressed mast cell degranulation and inhibited anaphylaxis. Taken together, our data indicate that PD stabilizes mast cells by suppressing FcεRI-induced Ca 2+ mobilization mainly through inhibiting Ca 2+ entry via CRACs, thus exerting a protective effect against PCA. -- Highlights: ► Polydatin can prevent the pathogenesis of passive cutaneous anaphylaxis in mice. ► Polydatin stabilizes mast cells by decreasing FcεRI-mediated degranulation. ► Polydatin suppresses Ca 2+ entry through CRAC channels in mast cells.

Preclinical evaluation of local JAK1 and JAK2 inhibition in cutaneous inflammation.

Science.gov (United States)

Fridman, Jordan S; Scherle, Peggy A; Collins, Robert; Burn, Timothy; Neilan, Claire L; Hertel, Denise; Contel, Nancy; Haley, Patrick; Thomas, Beth; Shi, Jack; Collier, Paul; Rodgers, James D; Shepard, Stacey; Metcalf, Brian; Hollis, Gregory; Newton, Robert C; Yeleswaram, Swamy; Friedman, Steven M; Vaddi, Kris

2011-09-01

JAKs are required for signaling initiated by several cytokines (e.g., IL-4, IL-12, IL-23, thymic stromal lymphopoietin (TSLP), and IFNγ) implicated in the pathogenesis of inflammatory skin diseases such as psoriasis and atopic dermatitis (AD). Direct antagonism of cytokines, such as IL-12 and IL-23 using ustekinumab, has proven effective in randomized studies in psoriasis patients. We hypothesized that local inhibition of cytokine signaling using topical administration of INCB018424, a small molecule inhibitor of JAK1 and JAK2, would provide benefit similar to systemic cytokine neutralization. In cellular assays, INCB018424 inhibits cytokine-induced JAK/signal transducers and activators of transcription (STAT) signaling and the resultant production of inflammatory proteins (e.g., IL-17, monocyte chemotactic protein-1, and IL-22) in lymphocytes and monocytes, with half-maximal inhibitory concentration values keratinocyte proliferation in a murine contact hypersensitivity model and inhibited tissue inflammation induced by either intradermal IL-23 or TSLP. Topical INCB018424 was also well tolerated in a 28-day safety study in Gottingen minipigs. These results suggest that localized JAK1/JAK2 inhibition may be therapeutic in a range of inflammatory skin disorders such as psoriasis and AD. Clinical evaluation of topical INCB018424 is ongoing.

The pathogenesis of foot-and-mouth disease in pigs

Directory of Open Access Journals (Sweden)

Carolina eStenfeldt

2016-05-01

Full Text Available The greatest proportion of foot-and-mouth disease (FMD clinical research has been dedicated to elucidating pathogenesis and enhancing vaccine protection in cattle with less efforts invested in studies specific to pigs. However, accumulated evidence from FMD outbreaks and experimental investigations suggest that critical components of FMD pathogenesis, immunology, and vaccinology cannot be extrapolated from investigations performed in cattle to explain or predict outcomes of infection or vaccination in pigs. Furthermore, it has been shown that failure to account for these differences may have substantial consequences when FMD outbreaks occur in areas with dense pig populations. Recent experimental studies have confirmed some aspects of conventional wisdom by demonstrating that pigs are more susceptible to FMD virus (FMDV infection via exposure of the upper gastrointestinal tract (oropharynx than through inhalation of virus. The infection spreads rapidly within groups of pigs that are housed together, although efficiency of transmission may vary depending on virus strain and exposure intensity. Multiple investigations have demonstrated that physical separation of pigs is sufficient to prevent virus transmission under experimental conditions. Detailed pathogenesis studies have recently demonstrated that specialized epithelium within porcine oropharyngeal tonsils constitute the primary infection sites following simulated-natural virus exposure. Furthermore, epithelium of the tonsil of the soft palate supports substantial virus replication during the clinical phase of infection, thus providing large amounts of virus that can be shed into the environment. Due to massive amplification and shedding of virus, acutely infected pigs constitute a considerable source of contagion. FMDV infection results in modulation of several components of the host immune response. The infection is ultimately cleared in association with a strong humoral response and, in

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

Molecular Determinants of Influenza Virus Pathogenesis in Mice

Science.gov (United States)

Katz, Jaqueline M.; York, Ian A.

2015-01-01

Mice are widely used for studying influenza virus pathogenesis and immunology because of their low cost, the wide availability of mouse-specific reagents, and the large number of mouse strains available, including knockout and transgenic strains. However, mice do not fully recapitulate the signs of influenza infection of humans: transmission of influenza between mice is much less efficient than in humans, and influenza viruses often require adaptation before they are able to efficiently replicate in mice. In the process of mouse adaptation, influenza viruses acquire mutations that enhance their ability to attach to mouse cells, replicate within the cells, and suppress immunity, among other functions. Many such mouse-adaptive mutations have been identified, covering all 8 genomic segments of the virus. Identification and analysis of these mutations have provided insight into the molecular determinants of influenza virulence and pathogenesis, not only in mice but also in humans and other species. In particular, several mouse-adaptive mutations of avian influenza viruses have proved to be general mammalian-adaptive changes that are potential markers of pre-pandemic viruses. As well as evaluating influenza pathogenesis, mice have also been used as models for evaluation of novel vaccines and anti-viral therapies. Mice can be a useful animal model for studying influenza biology as long as differences between human and mice infections are taken into account. PMID:25038937

Pharmacological Inhibition of Feline Immunodeficiency Virus (FIV

Directory of Open Access Journals (Sweden)

Dorothee Bienzle

2012-04-01

Full Text Available Feline immunodeficiency virus (FIV is a member of the retroviridae family of viruses and causes an acquired immunodeficiency syndrome (AIDS in domestic and non-domestic cats worldwide. Genome organization of FIV and clinical characteristics of the disease caused by the virus are similar to those of human immunodeficiency virus (HIV. Both viruses infect T lymphocytes, monocytes and macrophages, and their replication cycle in infected cells is analogous. Due to marked similarity in genomic organization, virus structure, virus replication and disease pathogenesis of FIV and HIV, infection of cats with FIV is a useful tool to study and develop novel drugs and vaccines for HIV. Anti-retroviral drugs studied extensively in HIV infection have targeted different steps of the virus replication cycle: (1 inhibition of virus entry into susceptible cells at the level of attachment to host cell surface receptors and co-receptors; (2 inhibition of fusion of the virus membrane with the cell membrane; (3 blockade of reverse transcription of viral genomic RNA; (4 interruption of nuclear translocation and viral DNA integration into host genomes; (5 prevention of viral transcript processing and nuclear export; and (6 inhibition of virion assembly and maturation. Despite much success of anti-retroviral therapy slowing disease progression in people, similar therapy has not been thoroughly investigated in cats. In this article we review current pharmacological approaches and novel targets for anti-lentiviral therapy, and critically assess potentially suitable applications against FIV infection in cats.

The role of biofilms and protozoa in Legionella pathogenesis: implications for drinking water

Science.gov (United States)

Current models to study Legionella pathogenesis include the use of primary macrophages and monocyte cell lines, various free-living protozoan species and murine models of pneumonia. However, there are very few studies of Legionella spp. pathogenesis aimed at associating the role ...

Deficiency of vitamin D and vitamin C in the pathogenesis of bronchial asthma.

Science.gov (United States)

Ginter, E; Simko, V

2016-01-01

Epidemiology of bronchial asthma (BA) indicates a marked paradox: rapid rise in the prevalence.Simultaneous decline in mortality is mostly related to improvement in the diagnosis and therapy. In many economically developed countries the BA affects more than 10 per cent of the population, while mortality related to this respiratory disorder is below 1/100,000. Factors favorably influencing mortality of BA include new more effective medications, decline in smoking and also improved nutrition, based on awareness of protective role of vitamins. Vitamin D deficiency has a number of biological effects that are potentially instrumental in the pathogenesis and severity of BA. Increased number of randomized, controlled, interventional studies is showing positive effects of vitamin D supplementation in pediatric and in adult BA. Oxidative stress is potentially an important pathogenic factor in the progression of BA. Vitamin C (ascorbic acid) belongs to the most effective nutritional antioxidants. By counteracting oxidants, reducing generation of reactive oxygen species, vitamin C may inhibit external attacks in the respiratory tract, thus modulating the development of BA (Fig. 2, Ref. 15).

Endoplasmic reticulum stress in pathogenesis of diabetic retinopathy and effect of calcium dobesilate

Institute of Scientific and Technical Information of China (English)

Yu-Min Gui; Ming Zhao; Jie Ding

2016-01-01

Objective:To study the mechanism of endoplasmic reticulum stress in the pathogenesis of diabetic retinopathy and effect of calcium dobesilate.Methods:A total of 120 diabetic retinopathy patients treated in our hospital from January 2010 to September 2015 were enrolled in this article. The serum endoplasmic reticulum stress protein and interleukin protein expression levels were analyzed before and after calcium dobesilate treatment. A total of 55 cases of healthy subjects receiving physical examination in our hospital during the same period were taken as control group.Results:Serum endoplasmic reticulum stress proteins PERK, CHOP and IRE as well as interleukin proteins IL1, IL2, IL6 and IL10 expression significantly increased, serum MDA level significantly increased while SOD, CAT and GSHpx levels significantly decreased in diabetic retinopathy patients, and compared with control group (P<0.01); after calcium dobesilate treatment, above factors were significantly restored (P<0.01).Conclusions: Diabetic retinopathy is closely related to endoplasmic reticulum stress and calcium dobesilate treatment may improve diabetic retinopathy by inhibiting endoplasmic reticulum stress.

Consensus strategy in genes prioritization and combined bioinformatics analysis for preeclampsia pathogenesis.

Science.gov (United States)

Tejera, Eduardo; Cruz-Monteagudo, Maykel; Burgos, Germán; Sánchez, María-Eugenia; Sánchez-Rodríguez, Aminael; Pérez-Castillo, Yunierkis; Borges, Fernanda; Cordeiro, Maria Natália Dias Soeiro; Paz-Y-Miño, César; Rebelo, Irene

2017-08-08

Preeclampsia is a multifactorial disease with unknown pathogenesis. Even when recent studies explored this disease using several bioinformatics tools, the main objective was not directed to pathogenesis. Additionally, consensus prioritization was proved to be highly efficient in the recognition of genes-disease association. However, not information is available about the consensus ability to early recognize genes directly involved in pathogenesis. Therefore our aim in this study is to apply several theoretical approaches to explore preeclampsia; specifically those genes directly involved in the pathogenesis. We firstly evaluated the consensus between 12 prioritization strategies to early recognize pathogenic genes related to preeclampsia. A communality analysis in the protein-protein interaction network of previously selected genes was done including further enrichment analysis. The enrichment analysis includes metabolic pathways as well as gene ontology. Microarray data was also collected and used in order to confirm our results or as a strategy to weight the previously enriched pathways. The consensus prioritized gene list was rationally filtered to 476 genes using several criteria. The communality analysis showed an enrichment of communities connected with VEGF-signaling pathway. This pathway is also enriched considering the microarray data. Our result point to VEGF, FLT1 and KDR as relevant pathogenic genes, as well as those connected with NO metabolism. Our results revealed that consensus strategy improve the detection and initial enrichment of pathogenic genes, at least in preeclampsia condition. Moreover the combination of the first percent of the prioritized genes with protein-protein interaction network followed by communality analysis reduces the gene space. This approach actually identifies well known genes related with pathogenesis. However, genes like HSP90, PAK2, CD247 and others included in the first 1% of the prioritized list need to be further

Multiple sclerosis pathogenesis: missing pieces of an old puzzle.

Science.gov (United States)

Rahmanzadeh, Reza; Brück, Wolfgang; Minagar, Alireza; Sahraian, Mohammad Ali

2018-06-08

Traditionally, multiple sclerosis (MS) was considered to be a CD4 T cell-mediated CNS autoimmunity, compatible with experimental autoimmune encephalitis model, which can be characterized by focal lesions in the white matter. However, studies of recent decades revealed several missing pieces of MS puzzle and showed that MS pathogenesis is more complex than the traditional view and may include the following: a primary degenerative process (e.g. oligodendroglial pathology), generalized abnormality of normal-appearing brain tissue, pronounced gray matter pathology, involvement of innate immunity, and CD8 T cells and B cells. Here, we review these findings and discuss their implications in MS pathogenesis.

Preeclampsia: Pathogenesis, Prevention, and Long-Term Complications.

Science.gov (United States)

Jim, Belinda; Karumanchi, S Ananth

2017-07-01

Preeclampsia continues to afflict 5% to 8% of all pregnancies throughout the world and is associated with significant morbidity and mortality to the mother and the fetus. Although the pathogenesis of the disorder has not yet been fully elucidated, current evidence suggests that imbalance in angiogenic factors is responsible for the clinical manifestations of the disorder, and may explain why certain populations are risk. In this review, we begin by demonstrating the roles that angiogenic factors play in pathogenesis of preeclampsia and its complications in the mother and the fetus. We then continue to report on the use of angiogenic markers as biomarkers to predict and risk-stratify disease. Strategies to treat preeclampsia by correcting the angiogenic balance, either by promoting proangiogenic factors or by removing antiangiogenic factors in both animal and human studies, are discussed. We end the review by summarizing status of the current preventive strategies and the long-term cardiovascular outcomes of women afflicted with preeclampsia. Copyright © 2017 Elsevier Inc. All rights reserved.

Hutchinson-Gilford progeria syndrome: review of the phenotype

NARCIS (Netherlands)

Hennekam, Raoul C. M.

2006-01-01

Hutchinson-Gilford progeria syndrome (HGPS) is a rare but well known entity characterized by extreme short stature, low body weight, early loss of hair, lipodystrophy, scleroderma, decreased joint mobility, osteolysis, and facial features that resemble aged persons. Cardiovascular compromise leads

Inhibition of cAMP-Activated Intestinal Chloride Secretion by Diclofenac: Cellular Mechanism and Potential Application in Cholera

OpenAIRE

Pongkorpsakol, Pawin; Pathomthongtaweechai, Nutthapoom; Srimanote, Potjanee; Soodvilai, Sunhapas; Chatsudthipong, Varanuj; Muanprasat, Chatchai

2014-01-01

Cyclic AMP-activated intestinal Cl- secretion plays an important role in pathogenesis of cholera. This study aimed to investigate the effect of diclofenac on cAMP-activated Cl- secretion, its underlying mechanisms, and possible application in the treatment of cholera. Diclofenac inhibited cAMP-activated Cl- secretion in human intestinal epithelial (T84) cells with IC50 of ∼ 20 µM. The effect required no cytochrome P450 enzyme-mediated metabolic activation. Interestingly, exposures of T84 cell...

Polydatin (PD) inhibits IgE-mediated passive cutaneous anaphylaxis in mice by stabilizing mast cells through modulating Ca{sup 2+} mobilization

Energy Technology Data Exchange (ETDEWEB)

Yuan, Meichun [Department of Pathophysiology, School of Medicine, Shenzhen University, Shenzhen 518060 (China); Department of Physiology, Hubei University of Medicine, Shiyan (China); Li, Jianjie [State Key Laboratory of Respiratory Disease for Allergy at Shengzhen University, Shenzhen 518060 (China); Lv, Jingzhang [Shenzhen Entry-Exit Inspection and Quarantine Bureau, Shenzhen 518045 (China); Mo, Xucheng; Yang, Chengbin [State Key Laboratory of Respiratory Disease for Allergy at Shengzhen University, Shenzhen 518060 (China); Chen, Xiangdong [Department of Pathophysiology, School of Medicine, Shenzhen University, Shenzhen 518060 (China); Liu, Zhigang [State Key Laboratory of Respiratory Disease for Allergy at Shengzhen University, Shenzhen 518060 (China); Liu, Jie, E-mail: ljljz@yahoo.com [Department of Pathophysiology, School of Medicine, Shenzhen University, Shenzhen 518060 (China)

2012-11-01

Mast cells play a key role in the pathogenesis of asthma and are a promising target for therapeutic intervention in asthma. This study investigated the effects of polydatin (PD), a resveratrol glucoside, on mast cell degranulation upon cross-linking of the high-affinity IgE receptors (FcεRI), as well as the anti-allergic activity of PD in vivo. Herein, we demonstrated that PD treatment for 30 min suppressed FcεRI-mediated mast cell degranulation in a dose-dependent manner. Concomitantly, PD significantly decreased FcεRI-mediated Ca{sup 2+} increase in mast cells. The suppressive effects of PD on FcεRI-mediated Ca{sup 2+} increase were largely inhibited by using LaCl{sub 3} to block the Ca{sup 2+} release-activated Ca{sup 2+} channels (CRACs). Furthermore, PD significantly inhibited Ca{sup 2+} entry through CRACs evoked by thapsigargin (TG). Knocking down protein expression of Orai1, the pore-forming subunit of CRACs, significantly decreased PD suppression of FcεRI-induced intracellular Ca{sup 2+} influx and mast cell degranulation. In a mouse model of mast cell-dependent passive cutaneous anaphylaxis (PCA), in vivo PD administration suppressed mast cell degranulation and inhibited anaphylaxis. Taken together, our data indicate that PD stabilizes mast cells by suppressing FcεRI-induced Ca{sup 2+} mobilization mainly through inhibiting Ca{sup 2+} entry via CRACs, thus exerting a protective effect against PCA. -- Highlights: ► Polydatin can prevent the pathogenesis of passive cutaneous anaphylaxis in mice. ► Polydatin stabilizes mast cells by decreasing FcεRI-mediated degranulation. ► Polydatin suppresses Ca{sup 2+} entry through CRAC channels in mast cells.

Pathogenesis of Acute Respiratory Distress Syndrome

Directory of Open Access Journals (Sweden)

A. M. Golubev

2012-01-01

Full Text Available Acute respiratory distress syndrome (ARDS is a common complication of many diseases. Its polyetiological pattern determines the specific features of lung morphological changes and the clinical course of ARDS. Objective: to analyze the pathogenesis of ARDS in the context of the general pathological processes underlying its development. Material and methods. More than 200 lungs from the people who had died from severe concomitant injury or ARDS-complicated pneumonia were investigated. More than 150 rat experiments simulated various types of lung injury: ventilator-induced lung injury with different ventilation parameters; reperfusion injuries (systemic circulation blockade due to 12-minute vascular fascicle ligation, followed by the recovery of cardiac performance and breathing; microcirculatory disorder (injection of a thromboplastin solution into the jugular vein; blood loss; betaine-pepsin aspiration; and closed chest injury. Different parts of the right and left lungs were histologically examined 1 and 3 hours and 1 and 3 days after initiation of the experiment. Lung pieces were fixed in 10% neutral formalin solution and embedded in paraffin. Histological sections were stained with hematoxylin and eosin and using the van Gieson and Weigert procedures; the Schiff test was used. Results. The influence of aggression factors (trauma, blood loss, aspiration, infection, etc. results in damage to the lung and particularly air-blood barrier structures (endothelium, alveolar epithelium, their basement membrane. In turn the alteration of cellular and extracellular structures is followed by the increased permeability of hemomicrocirculatory bed vessels, leading to the development of non-cardiogenic (interstitial, alveolar pulmonary edema that is a central component in the pathogenesis of ARDS. Conclusion. The diagnosis of the early manifestations of ARDS must account for the nature of an aggression factor, the signs confirming the alteration of the lung

Pathogenesis of helicobacter pylori infection involves interaction ...

African Journals Online (AJOL)

It is now clear that both bacterial virulence factors and host susceptibility play key roles in disease pathogenesis. The nature and levels of these interactions between these major factors has been found to determine the spectrum of clinical outcomes of the infection with this important bacterium. Virulence factors include the ...

Distinct Roles of Wnt/β-Catenin Signaling in the Pathogenesis of Chronic Obstructive Pulmonary Disease and Idiopathic Pulmonary Fibrosis

Science.gov (United States)

Shi, Juan; Li, Feng; Luo, Meihui; Wei, Jun

2017-01-01

Wnt signaling pathways are tightly controlled under a physiological condition, under which they play key roles in many biological functions, including cell fate specification and tissue regeneration. Increasing lines of evidence recently demonstrated that a dysregulated activation of Wnt signaling, particularly the Wnt/β-catenin signaling, was involved in the pathogenesis of chronic pulmonary diseases, such as chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF). In this respect, Wnt signaling interacts with other cellular signaling pathways to regulate the initiation and pathogenic procedures of airway inflammation and remodeling, pulmonary myofibroblast proliferation, epithelial-to-mesenchymal transition (EMT), and development of emphysema. Intriguingly, Wnt/β-catenin signaling is activated in IPF; an inhibition of this signaling leads to an alleviation of pulmonary inflammation and fibrosis in experimental models. Conversely, Wnt/β-catenin signaling is inactivated in COPD tissues, and its reactivation results in an amelioration of airspace enlargement with a restored alveolar epithelial structure and function in emphysema models. These studies thus imply distinct mechanisms of Wnt/β-catenin signaling in the pathogenesis of these two chronic pulmonary diseases, indicating potential targets for COPD and IPF treatments. This review article aims to summarize the involvement and pathogenic roles of Wnt signaling pathways in the COPD and IPF, with a focus on the implication of Wnt/β-catenin signaling as underlying mechanisms and therapeutic targets in these two incurable diseases. PMID:28588349

The effect of DPP-4 inhibition with sitagliptin on incretin secretion and on fasting and postprandial glucose turnover in subjects with impaired fasting glucose

DEFF Research Database (Denmark)

Bock, Gerlies; Man, Chiara Dalla; Micheletto, Francesco

2010-01-01

Abstract Objective: Low Glucagon-like Peptide-1 (GLP-1) concentrations have been observed in impaired fasting glucose (IFG). It is uncertain if these abnormalities contribute directly to the pathogenesis of IFG and impaired glucose tolerance. Dipeptidyl peptidase-4 (DPP-4) inhibitors raise incretin...... period, the mixed meal was repeated. Results: As expected, subjects with IFG who received placebo did not experience any change in glucose concentrations. Despite raising intact GLP-1 concentrations, treatment with sitagliptin did not alter either fasting or postprandial glucose, insulin or C....... Conclusions: DPP-4 inhibition did not alter fasting or postprandial glucose turnover in people with IFG. Low incretin concentrations are unlikely to be involved in the pathogenesis of IFG....

Polypoidal Choroidal Vasculopathy: Definition, Pathogenesis, Diagnosis, and Management.

Science.gov (United States)

Cheung, Chui Ming Gemmy; Lai, Timothy Y Y; Ruamviboonsuk, Paisan; Chen, Shih-Jen; Chen, Youxin; Freund, K Bailey; Gomi, Fomi; Koh, Adrian H; Lee, Won-Ki; Wong, Tien Yin

2018-05-01

Polypoidal choroidal vasculopathy (PCV) is an age-related macular degeneration (AMD) subtype and is seen particularly in Asians. Previous studies have suggested disparity in response to intravitreal injections of anti-vascular endothelial growth factor (VEGF) agents between PCV and typical AMD, and thus, the preferred treatment for PCV has remained unclear. Recent research has provided novel insights into the pathogenesis of PCV, and imaging studies based on OCT suggest that PCV belongs to a spectrum of conditions characterized by pachychoroid, in which disturbance in the choroidal circulation seems to be central to its pathogenesis. Advances in imaging, including enhanced depth imaging, swept-source OCT, en face OCT, and OCT angiography, have facilitated the diagnosis of PCV. Importantly, 2 large, multicenter randomized clinical trials evaluating the safety and efficacy of anti-VEGF monotherapy and combination with photodynamic therapy (PDT) recently reported initial first-year outcomes, providing level I evidence to guide clinicians in choosing the most appropriate therapy for PCV. In this review, we summarize the latest updates in the epidemiologic features, pathogenesis, and advances in imaging and treatment trials, with a focus on the most recent key clinical trials. Finally, we propose current management guidelines and recommendations to help clinicians manage patients with PCV. Remaining gaps in current understanding of PCV, such as significance of polyp closure, high recurrence rate, and heterogeneity within PCV, are highlighted where further research is needed. Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Diagnosis, pathogenesis and treatment of myositis: recent advances.

Science.gov (United States)

Carstens, P-O; Schmidt, J

2014-03-01

Dermatomyositis (DM), polymyositis (PM), necrotizing myopathy (NM) and inclusion body myositis (IBM) are four distinct subtypes of idiopathic inflammatory myopathies - in short myositis. Recent studies have shed some light on the unique pathogenesis of each entity. Some of the clinical features are distinct, but muscle biopsy is indispensable for making a reliable diagnosis. The use of magnetic resonance imaging of skeletal muscles and detection of myositis-specific autoantibodies have become useful additions to our diagnostic repertoire. Only few controlled trials are available to substantiate current treatment approaches for myositis and hopes are high that novel modalities will become available within the next few years. In this review we provide an up-to-date overview of the pathogenesis and diagnostic approach of myositis. We aim to present a guide towards therapeutic and general management. © 2013 British Society for Immunology.

Contribution of Panton-Valentine leukocidin in community-associated methicillin-resistant Staphylococcus aureus pathogenesis.

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Binh An Diep

2008-09-01

Full Text Available Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA strains typically carry genes encoding Panton-Valentine leukocidin (PVL. We used wild-type parental and isogenic PVL-deletion (Delta pvl strains of USA300 (LAC and SF8300 and USA400 (MW2 to test whether PVL alters global gene regulatory networks and contributes to pathogenesis of bacteremia, a hallmark feature of invasive staphylococcal disease. Microarray and proteomic analyses revealed that PVL does not alter gene or protein expression, thereby demonstrating that any contribution of PVL to CA-MRSA pathogenesis is not mediated through interference of global gene regulatory networks. Inasmuch as a direct role for PVL in CA-MRSA pathogenesis remains to be determined, we developed a rabbit bacteremia model of CA-MRSA infection to evaluate the effects of PVL. Following experimental infection of rabbits, an animal species whose granulocytes are more sensitive to the effects of PVL compared with the mouse, we found a contribution of PVL to pathogenesis over the time course of bacteremia. At 24 and 48 hours post infection, PVL appears to play a modest, but measurable role in pathogenesis during the early stages of bacteremic seeding of the kidney, the target organ from which bacteria were not cleared. However, the early survival advantage of this USA300 strain conferred by PVL was lost by 72 hours post infection. These data are consistent with the clinical presentation of rapid-onset, fulminant infection that has been associated with PVL-positive CA-MRSA strains. Taken together, our data indicate a modest and transient positive effect of PVL in the acute phase of bacteremia, thereby providing evidence that PVL contributes to CA-MRSA pathogenesis.

Molecular cloning and characterization of pathogenesis-related ...

African Journals Online (AJOL)

We described the cloning and characterization of pathogenesis-related protein 5 gene in maize, named ZmPR5 (GenBank Accession Number: HM230665). Molecular and bioinformatic analyses of ZmPR5 revealed an open reading frame (ORF) of 525 bp, encoding a protein of 175 amino acids (aa) and a deduced ...

Tick-borne encephalitis: Pathogenesis and clinical implications

Czech Academy of Sciences Publication Activity Database

Růžek, Daniel; Dobler, G.; Mantke, O. D.

2010-01-01

Roč. 8, č. 4 (2010), s. 223-232 ISSN 1477-8939 R&D Projects: GA ČR GPP302/10/P438; GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z60220518 Keywords : Tick-borne encephalitis * Tick-borne encephalitis virus * Pathogenesis * Clinical data Subject RIV: EE - Microbiology, Virology

Molecular cloning and characterization of pathogenesis-related ...

African Journals Online (AJOL)

use

2011-12-21

Dec 21, 2011 ... Available online at http://www.academicjournals.org/AJB ... November, 2011. We described the cloning and characterization of pathogenesis-related protein 5 gene in maize, named .... in two inbred lines was calculated using the ↵Ct method. .... Of the characterized PRs currently known, PR-1, PR-2,. PR-3 ...

The Role of the spv Genes in Salmonella Pathogenesis

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Donald G. Guiney

2011-06-01

Full Text Available Salmonella strains cause three main types of diseases in people: gastroenteritis, enteric (typhoid fever, and non-typhoid extra-intestinal disease with bacteremia. Genetic analysis indicates that each clinical syndrome requires distinct sets of virulence genes, and Salmonella isolates differ in their constellation of virulence traits. The spv locus is strongly associated with strains that cause non-typhoid bacteremia, but are not present in typhoid strains. The spv region contains three genes required for the virulence phenotype in mice: the positive transcriptional regulator spvR and two structural genes spvB and spvC. SpvB and SpvC are translocated into the host cell by the SPI-2 type-three secretion system. SpvB prevents actin polymerization by ADP-ribosylation of actin monomers, while SpvC has phosphothreonine lyase activity and has been shown to inhibit MAP kinase signaling. The exact mechanisms by which SpvB and SpvC act in concert to enhance virulence are still unclear. SpvB exhibits a cytotoxic effect on host cells and is required for delayed cell death by apoptosis following intracellular infection. Strains isolated from systemic infections of immune compromised patients, particularly HIV patients, usually carry the spv locus, strongly suggesting that CD4 T cells are required to control disease due to Salmonella that are spv positive. This association is not seen with typhoid fever, indicating that the pathogenesis and immunology of typhoid have fundamental differences from the syndrome of non-typhoid bacteremia.

Curcumin Protects against Atherosclerosis in Apolipoprotein E-Knockout Mice by Inhibiting Toll-like Receptor 4 Expression.

Science.gov (United States)

Zhang, Shanshan; Zou, Jun; Li, Peiyang; Zheng, Xiumei; Feng, Dan

2018-01-17

Toll-like receptor 4 (TLR4) has been reported to play a critical role in the pathogenesis of atherosclerosis, the current study aimed to investigate whether curcumin suppresses atherosclerosis development in ApoE-knockout (ApoE -/- ) mice by inhibiting TLR4 expression. ApoE -/- mice were fed a high-fat diet supplemented with or without curcumin (0.1% w/w) for 16 weeks. Curcumin supplementation significantly reduced TLR4 expression and macrophage infiltration in atherosclerotic plaques. Curcumin also reduced aortic interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) expression, nuclear factor-κB (NF-κB) activity, and plasma IL-1β, TNF-α, soluble VCAM-1 and ICAM-1 levels. In addition, aortic sinus sections revealed that curcumin treatment reduced the extent of atherosclerotic lesions and inhibited atherosclerosis development. In vitro, curcumin inhibited NF-κB activation in macrophages and reduced TLR4 expression induced by lipopolysaccharide. Our results indicate that curcumin protects against atherosclerosis at least partially by inhibiting TLR4 expression and its related inflammatory reaction.

The HAP Complex Governs Fumonisin Biosynthesis and Maize Kernel Pathogenesis in Fusarium verticillioides.

Science.gov (United States)

Ridenour, John B; Smith, Jonathon E; Bluhm, Burton H

2016-09-01

Contamination of maize ( Zea mays ) with fumonisins produced by the fungus Fusarium verticillioides is a global concern for food safety. Fumonisins are a group of polyketide-derived secondary metabolites linked to esophageal cancer and neural tube birth defects in humans and numerous toxicoses in livestock. Despite the importance of fumonisins in global maize production, the regulation of fumonisin biosynthesis during kernel pathogenesis is poorly understood. The HAP complex is a conserved, heterotrimeric transcriptional regulator that binds the consensus sequence CCAAT to modulate gene expression. Recently, functional characterization of the Hap3 subunit linked the HAP complex to the regulation of secondary metabolism and stalk rot pathogenesis in F. verticillioides . Here, we determine the involvement of HAP3 in fumonisin biosynthesis and kernel pathogenesis. Deletion of HAP3 suppressed fumonisin biosynthesis on both nonviable and live maize kernels and impaired pathogenesis in living kernels. Transcriptional profiling via RNA sequencing indicated that the HAP complex regulates at least 1,223 genes in F. verticillioides , representing nearly 10% of all predicted genes. Disruption of the HAP complex caused the misregulation of biosynthetic gene clusters underlying the production of secondary metabolites, including fusarins. Taken together, these results reveal that the HAP complex is a central regulator of fumonisin biosynthesis and kernel pathogenesis and works as both a positive and negative regulator of secondary metabolism in F. verticillioides .

Molecular pathogenesis of intrahepatic cholangiocarcinoma

DEFF Research Database (Denmark)

Andersen, Jesper Bøje

2014-01-01

Cholangiocarcinoma (CCA) is an orphan cancer of the hepatobiliary tract, the incidence of which has increased in the past decade. The molecular pathogenesis of this treatment-refractory disease is poorly understood. Desmoplasia is a key causal feature of CCA; however, a majority of tumors develop...... and individualization for precision therapies. Many questions persevere as to the evolutionary process and cellular origin of the initial transforming event, the context of intratumoral plasticity and the causal driver action. Next-generation sequencing has begun to underline the persistent alterations, which may...

Biology and pathogenesis of Acanthamoeba

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Siddiqui Ruqaiyyah

2012-01-01

Full Text Available Abstract Acanthamoeba is a free-living protist pathogen, capable of causing a blinding keratitis and fatal granulomatous encephalitis. The factors that contribute to Acanthamoeba infections include parasite biology, genetic diversity, environmental spread and host susceptibility, and are highlighted together with potential therapeutic and preventative measures. The use of Acanthamoeba in the study of cellular differentiation mechanisms, motility and phagocytosis, bacterial pathogenesis and evolutionary processes makes it an attractive model organism. There is a significant emphasis on Acanthamoeba as a Trojan horse of other microbes including viral, bacterial, protists and yeast pathogens.

Pathogenesis and treatment modalities of localized scleroderma.

Science.gov (United States)

Valančienė, Greta; Jasaitienė, Daiva; Valiukevičienė, Skaidra

2010-01-01

Localized scleroderma is a chronic inflammatory disease primarily of the dermis and subcutaneous fat that ultimately leads to a scar-like sclerosis of connective tissue. The disorder manifests as various plaques of different shape and size with signs of skin inflammation, sclerosis, and atrophy. This is a relatively rare inflammatory disease characterized by a chronic course, unknown etiology, and insufficiently clear pathogenesis. Many factors may influence its appearance: trauma, genetic factors, disorders of the immune system or hormone metabolism, viral infections, toxic substances or pharmaceutical agents, neurogenic factors, and Borrelia burgdorferi infection. Various therapeutic modalities are being used for the treatment of localized scleroderma. There is no precise treatment scheme for this disease. A majority of patients can be successfully treated with topical pharmaceutical agents and phototherapy, but some of them with progressive, disseminated, and causing disability localized scleroderma are in need of systemic treatment. The aim of this article is not only to dispute about the clinical and morphological characteristics of localized scleroderma, but also to present the newest generalized data about the possible origin, pathogenesis, and treatment modalities of this disease.

ALK1 signaling inhibits angiogenesis by cooperating with the Notch pathway.

Science.gov (United States)

Larrivée, Bruno; Prahst, Claudia; Gordon, Emma; del Toro, Raquel; Mathivet, Thomas; Duarte, Antonio; Simons, Michael; Eichmann, Anne

2012-03-13

Activin receptor-like kinase 1 (ALK1) is an endothelial-specific member of the TGF-β/BMP receptor family that is inactivated in patients with hereditary hemorrhagic telangiectasia (HHT). How ALK1 signaling regulates angiogenesis remains incompletely understood. Here we show that ALK1 inhibits angiogenesis by cooperating with the Notch pathway. Blocking Alk1 signaling during postnatal development in mice leads to retinal hypervascularization and the appearance of arteriovenous malformations (AVMs). Combined blockade of Alk1 and Notch signaling further exacerbates hypervascularization, whereas activation of Alk1 by its high-affinity ligand BMP9 rescues hypersprouting induced by Notch inhibition. Mechanistically, ALK1-dependent SMAD signaling synergizes with activated Notch in stalk cells to induce expression of the Notch targets HEY1 and HEY2, thereby repressing VEGF signaling, tip cell formation, and endothelial sprouting. Taken together, these results uncover a direct link between ALK1 and Notch signaling during vascular morphogenesis that may be relevant to the pathogenesis of HHT vascular lesions. Copyright © 2012 Elsevier Inc. All rights reserved.

Transport proteins promoting Escherichia coli pathogenesis

Science.gov (United States)

Tang, Fengyi; Saier, Milton H.

2014-01-01

Escherichia coli is a genetically diverse species infecting hundreds of millions of people worldwide annually. We examined seven well-characterized E. coli pathogens causing urinary tract infections, gastroenteritis, pyelonephritis and haemorrhagic colitis. Their transport proteins were identified and compared with each other and a non-pathogenic E. coli K12 strain to identify transport proteins related to pathogenesis. Each pathogen possesses a unique set of protein secretion systems for export to the cell surface or for injecting effector proteins into host cells. Pathogens have increased numbers of iron siderophore receptors and ABC iron uptake transporters, but the numbers and types of low-affinity secondary iron carriers were uniform in all strains. The presence of outer membrane iron complex receptors and high-affinity ABC iron uptake systems correlated, suggesting co-evolution. Each pathovar encodes a different set of pore-forming toxins and virulence-related outer membrane proteins lacking in K12. Intracellular pathogens proved to have a characteristically distinctive set of nutrient uptake porters, different from those of extracellular pathogens. The results presented in this report provide information about transport systems relevant to various types of E. coli pathogenesis that can be exploited in future basic and applied studies. PMID:24747185

Transport proteins promoting Escherichia coli pathogenesis.

Science.gov (United States)

Tang, Fengyi; Saier, Milton H

2014-01-01

Escherichia coli is a genetically diverse species infecting hundreds of millions of people worldwide annually. We examined seven well-characterized E. coli pathogens causing urinary tract infections, gastroenteritis, pyelonephritis and haemorrhagic colitis. Their transport proteins were identified and compared with each other and a non-pathogenic E. coli K12 strain to identify transport proteins related to pathogenesis. Each pathogen possesses a unique set of protein secretion systems for export to the cell surface or for injecting effector proteins into host cells. Pathogens have increased numbers of iron siderophore receptors and ABC iron uptake transporters, but the numbers and types of low-affinity secondary iron carriers were uniform in all strains. The presence of outer membrane iron complex receptors and high-affinity ABC iron uptake systems correlated, suggesting co-evolution. Each pathovar encodes a different set of pore-forming toxins and virulence-related outer membrane proteins lacking in K12. Intracellular pathogens proved to have a characteristically distinctive set of nutrient uptake porters, different from those of extracellular pathogens. The results presented in this report provide information about transport systems relevant to various types of E. coli pathogenesis that can be exploited in future basic and applied studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Roles of Environmental Pollutants in the Pathogenesis and ...

African Journals Online (AJOL)

ADOWIE PERE

Toxic chemicals in pollutants may destroy or cause mutation ... Keywords: Diabetes, Pathogenesis, Pancreas, Mutation, Insulin, Blood vessel. INTRODUCTION. Diabetes is a chronic disease that occurs either when .... alter insulin metabolism.

Invasive mold infections: virulence and pathogenesis of mucorales.

Science.gov (United States)

Morace, Giulia; Borghi, Elisa

2012-01-01

Mucorales have been increasingly reported as cause of invasive fungal infections in immunocompromised subjects, particularly in patients with haematological malignancies or uncontrolled diabetes mellitus and in those under deferoxamine treatment or undergoing dialysis. The disease often leads to a fatal outcome, but the pathogenesis of the infection is still poorly understood as well as the role of specific virulence determinants and the interaction with the host immune system. Members of the order Mucorales are responsible of almost all cases of invasive mucormycoses, the majority of the etiological agents belonging to the Mucoraceae family. Mucorales are able to produce various proteins and metabolic products toxic to animals and humans, but the pathogenic role of these potential virulence factors is unknown. The availability of free iron in plasma and tissues is believed to be crucial for the pathogenesis of these mycoses. Vascular invasion and neurotropism are considered common pathogenic features of invasive mucormycoses.

Osteonecrosis. Part 1. Risk factors and pathogenesis

Directory of Open Access Journals (Sweden)

Ekaterina Valeriyevna Ilyinykh

2013-01-01

Full Text Available The paper considers different risk factors for osteonecrosis (ON and some aspects of its pathogenesis: impairments in the differentiation of stromal cells, the vascular provision of intraand extravasal genesis, the quality of proper bone tissue due to generalized or local osteoporosis, intravascular coagulation factors contributing to microthrombogenesis. The basic types of ON are identified.

Effects on selective serotonin antagonism on central neurotransmission

Science.gov (United States)

Aggression and cannibalism in laying hens can differ in intensity and degree due to many factors, including genetics. Behavioral analysis of DeKalb XL (DXL) and high group productivity and survivability (HGPS) strains revealed high and low aggressiveness, respectively. However, the exact genetic me...

Polycyclic aromatic hydrocarbons and cytochrome P450 in HIV pathogenesis

Science.gov (United States)

Rao, P. S. S.; Kumar, Santosh

2015-01-01

High prevalence of cigarette smoking in HIV patients is associated with increased HIV pathogenesis and disease progression. While the effect of smoking on the occurrence of lung cancer has been studied extensively, the association between smoking and HIV pathogenesis is poorly studied. We have recently shown the possible role of cytochrome P450 (CYP) in smoking/nicotine-mediated viral replication. In this review, we focus on the potential role of CYP pathway in polycyclic aromatic hydrocarbons (PAH), important constituents of cigarette smoke, mediated HIV pathogenesis. More specifically, we will discuss the role of CYP1A1 and CYP1B1, which are the major PAH-activating CYP enzymes. Our results have shown that treatment with cigarette smoke condensate (CSC) increases viral replication in HIV-infected macrophages. CSC contains PAH, which are known to be activated by CYP1A1 and CYP1B1 into procarcinogens/toxic metabolites. The expression of these CYPs is regulated by aryl hydrocarbon receptors (AHR), the cellular target of PAH, and an important player in various diseases including cancer. We propose that PAH/AHR-mediated CYP pathway is a novel target to develop new interventions for HIV positive smokers. PMID:26082767

Oral candidiasis: pathogenesis, clinical presentation, diagnosis and treatment strategies.

Science.gov (United States)

Lalla, Rajesh V; Patton, Lauren L; Dongari-Bagtzoglou, Anna

2013-04-01

Oral candidiasis is a clinical fungal infection that is the most common opportunistic infection affecting the human oral cavity. This article reviews the pathogenesis, clinical presentations, diagnosis and treatmentstrategies for oral candidiasis.

Modern views on the epidemiology, etiology and pathogenesis of gynecomastia

Directory of Open Access Journals (Sweden)

Yu. N. Yashina

2014-01-01

Full Text Available The review deals with one of the pressing andrological issues – gynecomastia, its etiology and pathogenesis. Based on the current epidemiological and experimental data, most common etiological factors of gynecomastia were investigated. A multiple-valued role of various causes of gynecomastia in several age-groups was revealed. Literature data show that gynecomastia may be a manifestation of various diseases: endocrine, genetic, systematic. As well as that, gynecomastia may occur in patients with oncological diseases. However, gynecomastia can be an iatrogenic complication. Currently, we continue to make insights to the problem of gynecomastia in order to be able to classify its etiological factors and determine its basic pathogenesis pathways.

Tryptophan-2,3-dioxygenase (TDO) inhibition ameliorates neurodegeneration by modulation of kynurenine pathway metabolites.

Science.gov (United States)

Breda, Carlo; Sathyasaikumar, Korrapati V; Sograte Idrissi, Shama; Notarangelo, Francesca M; Estranero, Jasper G; Moore, Gareth G L; Green, Edward W; Kyriacou, Charalambos P; Schwarcz, Robert; Giorgini, Flaviano

2016-05-10

Metabolites of the kynurenine pathway (KP) of tryptophan (TRP) degradation have been closely linked to the pathogenesis of several neurodegenerative disorders. Recent work has highlighted the therapeutic potential of inhibiting two critical regulatory enzymes in this pathway-kynurenine-3-monooxygenase (KMO) and tryptophan-2,3-dioxygenase (TDO). Much evidence indicates that the efficacy of KMO inhibition arises from normalizing an imbalance between neurotoxic [3-hydroxykynurenine (3-HK); quinolinic acid (QUIN)] and neuroprotective [kynurenic acid (KYNA)] KP metabolites. However, it is not clear if TDO inhibition is protective via a similar mechanism or if this is instead due to increased levels of TRP-the substrate of TDO. Here, we find that increased levels of KYNA relative to 3-HK are likely central to the protection conferred by TDO inhibition in a fruit fly model of Huntington's disease and that TRP treatment strongly reduces neurodegeneration by shifting KP flux toward KYNA synthesis. In fly models of Alzheimer's and Parkinson's disease, we provide genetic evidence that inhibition of TDO or KMO improves locomotor performance and ameliorates shortened life span, as well as reducing neurodegeneration in Alzheimer's model flies. Critically, we find that treatment with a chemical TDO inhibitor is robustly protective in these models. Consequently, our work strongly supports targeting of the KP as a potential treatment strategy for several major neurodegenerative disorders and suggests that alterations in the levels of neuroactive KP metabolites could underlie several therapeutic benefits.

Innovative approach for urease inhibition by Ficus carica extract-fabricated silver nanoparticles: An in vitro study.

Science.gov (United States)

Borase, Hemant P; Salunkhe, Rahul B; Patil, Chandrashekhar D; Suryawanshi, Rahul K; Salunke, Bipinchandra K; Wagh, Nilesh D; Patil, Satish V

2015-01-01

In the present study, a rapid, low-cost, and ecofriendly method of stable silver nanoparticles (AgNPs) synthesis using leaves extract of Ficus carica (F. carica), a plant with diverse metabolic consortium, is reported for the first time. An absorption peak at 422 nm in UV-Vis spectroscopy, a spherical shape with an average size of 21 nm in transmission electron microscopy, and crystalline nature in X-ray powder diffraction studies were observed for the synthesized AgNPs. Fourier transform infrared analysis indicated that proteins of F. carica might have a vital role in AgNP synthesis and stabilization. AgNPs were found to inhibit urease, a key enzyme responsible for the survival and pathogenesis of the bacterium, Helicobacter pylori. Inhibition of urease by AgNPs was monitored spectrophotometrically by the evaluation of ammonia release. The urease inhibition potential of AgNPs can be explored in the treatment of H. pylori by preparing novel combinations of standard drugs with AgNPs- or AgNPs-encapsulated drug molecules. © 2015 International Union of Biochemistry and Molecular Biology, Inc.

NSs protein of Schmallenberg virus counteracts the antiviral response of the cell by inhibiting its transcriptional machinery.

Science.gov (United States)

Barry, Gerald; Varela, Mariana; Ratinier, Maxime; Blomström, Anne-Lie; Caporale, Marco; Seehusen, Frauke; Hahn, Kerstin; Schnettler, Esther; Baumgärtner, Wolfgang; Kohl, Alain; Palmarini, Massimo

2014-08-01

Bunyaviruses have evolved a variety of strategies to counteract the antiviral defence systems of mammalian cells. Here we show that the NSs protein of Schmallenberg virus (SBV) induces the degradation of the RPB1 subunit of RNA polymerase II and consequently inhibits global cellular protein synthesis and the antiviral response. In addition, we show that the SBV NSs protein enhances apoptosis in vitro and possibly in vivo, suggesting that this protein could be involved in SBV pathogenesis in different ways. © 2014 The Authors.

Hidradenitis suppurativa : From pathogenesis to emerging treatment options

NARCIS (Netherlands)

Dickinson-Blok, Janine Louise

2015-01-01

Hidradenitis suppurativa (HS) is a chronic skin disease that is characterized by inflammation of the hair follicles. The cause of HS is largely unknown and the disease remains difficult to treat. Mrs. Janine Dickinson-Blok studied the pathogenesis of HS and the efficacy of existing and emerging

Persistent perineal sinus. Incidence, pathogenesis, risk factors, and management

International Nuclear Information System (INIS)

Lohsiriwat, V.

2009-01-01

This review discusses the incidence, pathogenesis, risk factors, diagnosis, and therapeutic options for persistent perineal sinus (PPS), defined as a perineal wound that remains unhealed more than 6 months after surgery. The incidence of PPS after surgery for inflammatory bowel disease (IBD) ranges from 3% to 70% and after abdominoperineal resection (APR) for Low rectal cancer, it can be up to 30%. These unhealed wounds are frequently related to perioperative pelvic or perineal sepsis. Crohn's disease (CD) and neoadjuvant radiation therapy are also important risk factors. The management of PPS is based on an understanding of pathogenesis and clinical grounds. The advantages and disadvantages of the current therapeutic approaches, including the topical administration of various drugs, vacuum-assisted closure, and perineal reconstruction with a muscle flap or a myocutaneous flap are also discussed. (author)

Genes, autoimmunity and pathogenesis of rheumatic heart disease

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Guilherme, L; Köhler, K F; Postol, E; Kalil, J

2011-01-01

Pathogenesis of rheumatic heart disease (RHD) remains incompletely understood. Several genes associated with RHD have been described; most of these are involved with immune responses. Single nucleotide polymorphisms in a number of genes affect patients with RHD compared to controls. Molecular mimicry between streptococcal antigens and human proteins, including cardiac myosin epitopes, vimentin and other intracellular proteins is central to the pathogenesis of RHD. Autoreactive T cells migrate from the peripheral blood to the heart and proliferate in the valves in response to stimulation with specific cytokines. The types of cells involved in the inflammation as well as different cytokine profiles in these patients are being investigated. High TNF alpha, interferon gamma, and low IL4 are found in the rheumatic valve suggesting an imbalance between Th1 and Th2 cytokines and probably contributing to the progressive and permanent valve damage. Animal model of ARF in the Lewis rat may further contribute towards understanding the ARF

Invasive Mold Infections: Virulence and Pathogenesis of Mucorales

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Giulia Morace

2012-01-01

Full Text Available Mucorales have been increasingly reported as cause of invasive fungal infections in immunocompromised subjects, particularly in patients with haematological malignancies or uncontrolled diabetes mellitus and in those under deferoxamine treatment or undergoing dialysis. The disease often leads to a fatal outcome, but the pathogenesis of the infection is still poorly understood as well as the role of specific virulence determinants and the interaction with the host immune system. Members of the order Mucorales are responsible of almost all cases of invasive mucormycoses, the majority of the etiological agents belonging to the Mucoraceae family. Mucorales are able to produce various proteins and metabolic products toxic to animals and humans, but the pathogenic role of these potential virulence factors is unknown. The availability of free iron in plasma and tissues is believed to be crucial for the pathogenesis of these mycoses. Vascular invasion and neurotropism are considered common pathogenic features of invasive mucormycoses.

Penile cancer: epidemiology, pathogenesis and prevention.

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Bleeker, M C G; Heideman, D A M; Snijders, P J F; Horenblas, S; Dillner, J; Meijer, C J L M

2009-04-01

Penile cancer is a disease with a high morbidity and mortality. Its prevalence is relatively rare, but the highest in some developing countries. Insight into its precursor lesions, pathogenesis and risk factors offers options to prevent this potentially mutilating disease. This review presents an overview of the different histologically and clinically identified precursor lesions of penile cancer and discusses the molecular pathogenesis, including the role of HPV in penile cancer development. A systematic review of the literature evaluating penile carcinogenesis, risk factors and molecular mechanisms involved. Careful monitoring of men with lichen sclerosis, genital Bowen's disease, erythroplasia of Queyrat and bowenoid papulosis seems useful, thereby offering early recognition of penile cancer and, subsequently, conservative therapeutic options. Special attention is given to flat penile lesions, which contain high numbers of HPV. Their role in HPV transmission to sexual partners is highlighted, but their potential to transform as a precursor lesion into penile cancer has been unsatisfactorily explored. Further research should not only focus on HPV mediated pathogenic pathways but also on the non-HPV related molecular and genetic factors that play a role in penile cancer development. Options for prevention of penile cancer include (neonatal) circumcision, limitation of penile HPV infections (either by prophylactic vaccination or condom use), prevention of phimosis, treatment of chronic inflammatory conditions, limiting PUVA treatment, smoking cessation and hygienic measures.

Channelopathy Pathogenesis in Autism Spectrum Disorders

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Galina eSchmunk

2013-11-01

Full Text Available Autism spectrum disorder (ASD is a syndrome that affects normal brain development and is characterized by impaired social interaction as well as verbal and non-verbal communication and by repetitive, stereotypic behavior. ASD is a complex disorder arising from a combination of multiple genetic and environmental factors that are independent from racial, ethnic and socioeconomical status. The high heritability of ASD suggests a strong genetic basis for the disorder. Furthermore, a mounting body of evidence implies a role of various ion channel gene defects (channelopathies in the pathogenesis of autism. Indeed, recent genome-wide association, and whole exome- and whole- genome resequencing studies linked polymorphisms and rare variants in calcium, sodium and potassium channels and their subunits with susceptibility to ASD, much as they do with bipolar disorder, schizophrenia and other neuropsychiatric disorders, and animal models with these genetic variations recapitulate endophenotypes considered to be correlates of autistic behavior seen in patients. An ion flux across the membrane regulates a variety of cell functions, from generation of action potentials to gene expression and cell morphology, thus it is not surprising that channelopathies have profound effects on brain functions. In the present work, we summarize existing evidence for the role of ion channel gene defects in the pathogenesis of autism with a focus on calcium signaling and its downstream effects.

Ursodeoxycholic acid inhibits TNFα-induced IL-8 release from monocytes.

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O'Dwyer, Aoife M; Lajczak, Natalia K; Keyes, Jennifer A; Ward, Joseph B; Greene, Catherine M; Keely, Stephen J

2016-08-01

Monocytes are critical to the pathogenesis of inflammatory bowel disease (IBD) as they infiltrate the mucosa and release cytokines that drive the inflammatory response. Ursodeoxycholic acid (UDCA), a naturally occurring bile acid with anti-inflammatory actions, has been proposed as a potential new therapy for IBD. However, its effects on monocyte function are not yet known. Primary monocytes from healthy volunteers or cultured U937 monocytes were treated with either the proinflammatory cytokine, TNFα (5 ng/ml) or the bacterial endotoxin, lipopolysaccharide (LPS; 1 μg/ml) for 24 h, in the absence or presence of UDCA (25-100 μM). IL-8 release into the supernatant was measured by ELISA. mRNA levels were quantified by qPCR and changes in cell signaling proteins were determined by Western blotting. Toxicity was assessed by measuring lactate dehydrogenase (LDH) release. UDCA treatment significantly attenuated TNFα-, but not LPS-driven, release of IL-8 from both primary and cultured monocytes. UDCA inhibition of TNFα-driven responses was associated with reduced IL-8 mRNA expression. Both TNFα and LPS stimulated NFκB activation in monocytes, while IL-8 release in response to both cytokines was attenuated by an NFκB inhibitor, BMS-345541. Interestingly, UDCA inhibited TNFα-, but not LPS-stimulated, NFκB activation. Finally, TNFα, but not LPS, induced phosphorylation of TNF receptor associated factor (TRAF2), while UDCA cotreatment attenuated this response. We conclude that UDCA specifically inhibits TNFα-induced IL-8 release from monocytes by inhibiting TRAF2 activation. Since such actions would serve to dampen mucosal immune responses in vivo, our data support the therapeutic potential of UDCA for IBD. Copyright © 2016 the American Physiological Society.

Effects of protease-activated receptor 1 inhibition on anxiety and fear following status epilepticus.

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Bogovyk, Ruslan; Lunko, Oleksii; Fedoriuk, Mihail; Isaev, Dmytro; Krishtal, Oleg; Holmes, Gregory L; Isaeva, Elena

2017-02-01

Protease-activated receptor 1 (PAR1) is an important contributor to the pathogenesis of a variety of brain disorders associated with a risk of epilepsy development. Using the lithium-pilocarpine model of temporal lobe epilepsy (TLE), we recently showed that inhibition of this receptor during the first ten days after pilocarpine-induced status epilepticus (SE) results in substantial anti-epileptogenic and neuroprotective effects. As PAR1 is expressed in the central nervous system regions of importance for processing emotional reactions, including amygdala and hippocampus, and TLE is frequently associated with a chronic alteration of the functions of these regions, we tested the hypothesis that PAR1 inhibition could modulate emotionally driven behavioral responses of rats experiencing SE. We showed that SE induces a chronic decrease in the animals' anxiety-related behavior and an increase of locomotor activity. PAR1 inhibition after SE abolished the alteration of the anxiety level but does not affect the increase of locomotor activity in the open field and elevated plus maze tests. Moreover, while PAR1 inhibition produces an impairment of memory recall in the context fear conditioning paradigm in the control group, it substantially improves contextual and cued fear learning in rats experiencing SE. These data suggest that PAR1-dependent signaling is involved in the mechanisms underlying emotional disorders in epilepsy. Copyright © 2016 Elsevier Inc. All rights reserved.

Pathogenesis and immunotherapy in cutaneous psoriasis: what can rheumatologists learn?

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Alexander, Helen; Nestle, Frank O

2017-01-01

This review presents our current understanding of the pathogenesis and treatment of psoriasis with a particular focus on recent areas of research and emerging concepts. Psoriasis arises in genetically predisposed individuals who have an abnormal innate and adaptive immune response to environmental factors. Recent studies have identified novel genetic, epigenetic and immunological factors that play a role in the disease pathogenesis. There is emerging evidence for the role of the skin microbiome in psoriasis. Studies have shown reduced diversity and altered composition of the skin microbiota in psoriasis. Recent advances in our understanding of the complex immunopathogenesis of psoriasis have led to the identification of crucial cytokines and cell signalling pathways that are targeted by a range of immunotherapies.

Toll-like receptor activation in the pathogenesis of lupus nephritis.

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Lorenz, Georg; Lech, Maciej; Anders, Hans-Joachim

2017-12-01

The pathogenesis of systemic lupus erythematosus (SLE) and lupus nephritis is complex but no longer enigmatic. Much progress has been made to on the polygenetic origin of lupus in identifying gene variants that permit the loss of tolerance against nuclear autoantigens. Along the same line in about 50% of lupus patients additional genetic weaknesses promote immune complex glomerulonephritis and filtration barrier dysfunction. Here we briefly summarize the pathogenesis of SLE with a focus on loss of tolerance and the role of toll-like receptors in the "pseudo"-antiviral immunity concept of systemic lupus. In addition, we discuss the local role of Toll-like receptors in intrarenal inflammation and kidney remodeling. Copyright © 2016 Elsevier Inc. All rights reserved.

Bioinformatics Analysis Reveals Genes Involved in the Pathogenesis of Ameloblastoma and Keratocystic Odontogenic Tumor.

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Santos, Eliane Macedo Sobrinho; Santos, Hércules Otacílio; Dos Santos Dias, Ivoneth; Santos, Sérgio Henrique; Batista de Paula, Alfredo Maurício; Feltenberger, John David; Sena Guimarães, André Luiz; Farias, Lucyana Conceição

2016-01-01

Pathogenesis of odontogenic tumors is not well known. It is important to identify genetic deregulations and molecular alterations. This study aimed to investigate, through bioinformatic analysis, the possible genes involved in the pathogenesis of ameloblastoma (AM) and keratocystic odontogenic tumor (KCOT). Genes involved in the pathogenesis of AM and KCOT were identified in GeneCards. Gene list was expanded, and the gene interactions network was mapped using the STRING software. "Weighted number of links" (WNL) was calculated to identify "leader genes" (highest WNL). Genes were ranked by K-means method and Kruskal-Wallis test was used (Preview data was used to corroborate the bioinformatics data. CDK1 was identified as leader gene for AM. In KCOT group, results show PCNA and TP53 . Both tumors exhibit a power law behavior. Our topological analysis suggested leader genes possibly important in the pathogenesis of AM and KCOT, by clustering coefficient calculated for both odontogenic tumors (0.028 for AM, zero for KCOT). The results obtained in the scatter diagram suggest an important relationship of these genes with the molecular processes involved in AM and KCOT. Ontological analysis for both AM and KCOT demonstrated different mechanisms. Bioinformatics analyzes were confirmed through literature review. These results may suggest the involvement of promising genes for a better understanding of the pathogenesis of AM and KCOT.

Inhibition of neutral sphingomyelinase decreases elevated levels of inducible nitric oxide synthase and apoptotic cell death in ocular hypertensive rats

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Aslan, Mutay, E-mail: mutayaslan@akdeniz.edu.tr [Department of Medical Biochemistry, Akdeniz University Faculty of Medicine, Antalya (Turkey); Basaranlar, Goksun [Department of Biophysics, Akdeniz University Faculty of Medicine, Antalya (Turkey); Unal, Mustafa [Department of Ophthalmology, Akdeniz University Faculty of Medicine, Antalya (Turkey); Ciftcioglu, Akif [Department of Pathology, Akdeniz University Faculty of Medicine, Antalya (Turkey); Derin, Narin [Department of Biophysics, Akdeniz University Faculty of Medicine, Antalya (Turkey); Mutus, Bulent [Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario (Canada)

2014-11-01

Endoplasmic reticulum (ER) stress and excessive nitric oxide production via induction of inducible nitric oxide synthase (NOS2) have been implicated in the pathogenesis of neuronal retinal cell death in ocular hypertension. Neutral sphingomyelinase (N-SMase)/ceramide pathway can regulate NOS2 expression, hence this study determined the role of selective neutral sphingomyelinase (N-SMase) inhibition on retinal NOS2 levels, ER stress, apoptosis and visual evoked potentials (VEPs) in a rat model of elevated intraocular pressure (EIOP). NOS2 expression and retinal protein nitration were significantly greater in EIOP and significantly decreased with N-SMase inhibition. A significant increase was observed in retinal ER stress markers pPERK, CHOP and GRP78 in EIOP, which were not significantly altered by N-SMase inhibition. Retinal TUNEL staining showed increased apoptosis in all EIOP groups; however N-SMase inhibition significantly decreased the percent of apoptotic cells in EIOP. Caspase-3, -8 and -9 activities were significantly increased in EIOP and returned to baseline levels following N-SMase inhibition. Latencies of all VEP components were significantly prolonged in EIOP and shortened following N-SMase inhibition. Data confirm the role of nitrative injury in EIOP and highlight the protective effect of N-SMase inhibition in EIOP via down-regulation of NOS2 levels and nitrative stress. - Highlights: • Inhibition of N-SMase decreases NOS2 levels in ocular hypertension. • Inhibition of N-SMase decreases protein nitration in ocular hypertension. • Inhibition of N-SMase decreases caspase activation in ocular hypertension. • Inhibition of N-SMase decreases apoptosis in ocular hypertension.

Epstein-Barr Virus-Encoded RNAs: Key Molecules in Viral Pathogenesis

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Iwakiri, Dai [Institute for Genetic Medicine, Hokkaido University, N15 W7 Kita-Ku, Sapporo 060-0815 (Japan)

2014-08-06

The Epstein-Barr virus (EBV) is known as an oncogenic herpesvirus that has been implicated in the pathogenesis of various malignancies. EBV-encoded RNAs (EBERs) are non-coding RNAs expressed abundantly in latently EBV-infected cells. Herein, I summarize the current understanding of the functions of EBERs, including the interactions with cellular factors through which EBERs contribute to EBV-mediated pathogenesis. Previous studies have demonstrated that EBERs are responsible for malignant phenotypes in lymphoid cells, and can induce several cytokines that can promote the growth of various EBV-infected cancer cells. EBERs were also found to bind retinoic acid-inducible gene I (RIG-I) and thus activate its downstream signaling. Furthermore, EBERs induce interleukin-10, an autocrine growth factor for Burkitt’s lymphoma cells, by activating RIG-I/interferon regulatory factor 3 pathway, suggesting that EBER-mediated innate immune signaling modulation contributes to EBV-mediated oncogenesis. Recently, EBV-infected cells were reported to secret EBERs, which were then recognized by toll-like receptor 3 (TLR3), leading to the induction of type I interferon and inflammatory cytokines, and subsequent immune activation. Furthermore, EBER1 was detected in the sera of patients with active EBV-infectious diseases, suggesting that EBER1-meidated TLR3 signaling activation could account for the pathogenesis of active EBV-infectious diseases.

Epstein-Barr Virus-Encoded RNAs: Key Molecules in Viral Pathogenesis

International Nuclear Information System (INIS)

Iwakiri, Dai

2014-01-01

The Epstein-Barr virus (EBV) is known as an oncogenic herpesvirus that has been implicated in the pathogenesis of various malignancies. EBV-encoded RNAs (EBERs) are non-coding RNAs expressed abundantly in latently EBV-infected cells. Herein, I summarize the current understanding of the functions of EBERs, including the interactions with cellular factors through which EBERs contribute to EBV-mediated pathogenesis. Previous studies have demonstrated that EBERs are responsible for malignant phenotypes in lymphoid cells, and can induce several cytokines that can promote the growth of various EBV-infected cancer cells. EBERs were also found to bind retinoic acid-inducible gene I (RIG-I) and thus activate its downstream signaling. Furthermore, EBERs induce interleukin-10, an autocrine growth factor for Burkitt’s lymphoma cells, by activating RIG-I/interferon regulatory factor 3 pathway, suggesting that EBER-mediated innate immune signaling modulation contributes to EBV-mediated oncogenesis. Recently, EBV-infected cells were reported to secret EBERs, which were then recognized by toll-like receptor 3 (TLR3), leading to the induction of type I interferon and inflammatory cytokines, and subsequent immune activation. Furthermore, EBER1 was detected in the sera of patients with active EBV-infectious diseases, suggesting that EBER1-meidated TLR3 signaling activation could account for the pathogenesis of active EBV-infectious diseases

Calpain Inhibition Reduces Axolemmal Leakage in Traumatic Axonal Injury

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János Sándor

2009-12-01

Full Text Available Calcium-induced, calpain-mediated proteolysis (CMSP has recently been implicated to the pathogenesis of diffuse (traumatic axonal injury (TAI. Some studies suggested that subaxolemmal CMSP may contribute to axolemmal permeability (AP alterations observed in TAI. Seeking direct evidence for this premise we investigated whether subaxolemmal CMSP may contribute to axolemmal permeability alterations (APA and pre-injury calpain-inhibition could reduce AP in a rat model of TAI. Horseradish peroxidase (HRP, a tracer that accumulates in axons with APA was administered one hour prior to injury into the lateral ventricle; 30 min preinjury a single tail vein bolus injection of 30 mg/kg MDL-28170 (a calpain inhibitor or its vehicle was applied in Wistar rats exposed to impact acceleration brain injury. Histological detection of traumatically injured axonal segments accumulating HRP and statistical analysis revealed that pre-injury administration of the calpain inhibitor MDL-28170 significantly reduced the average length of HRP-labeled axonal segments. The axono-protective effect of pre-injury calpain inhibition recently demonstrated with classical immunohistochemical markers of TAI was further corroborated in this experiment; significant reduction of the length of labeled axons in the drug-treated rats implicate CMSP in the progression of altered AP in TAI.

Basal cell carcinoma pathogenesis and therapy involving hedgehog signaling and beyond.

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Bakshi, Anshika; Chaudhary, Sandeep C; Rana, Mehtab; Elmets, Craig A; Athar, Mohammad

2017-12-01

Basal cell carcinoma (BCC) of the skin is driven by aberrant hedgehog signaling. Thus blocking this signaling pathway by small molecules such as vismodegib inhibits tumor growth. Primary cilium in the epidermal cells plays an integral role in the processing of hedgehog signaling-related proteins. Recent genomic studies point to the involvement of additional genetic mutations that might be associated with the development of BCCs, suggesting significance of other signaling pathways, such as WNT, NOTCH, mTOR, and Hippo, aside from hedgehog in the pathogenesis of this human neoplasm. Some of these pathways could be regulated by noncoding microRNA. Altered microRNA expression profile is recognized with the progression of these lesions. Stopping treatment with Smoothened (SMO) inhibitors often leads to tumor reoccurrence in the patients with basal cell nevus syndrome, who develop 10-100 of BCCs. In addition, the initial effectiveness of these SMO inhibitors is impaired due to the onset of mutations in the drug-binding domain of SMO. These data point to a need to develop strategies to overcome tumor recurrence and resistance and to enhance efficacy by developing novel single agent-based or multiple agents-based combinatorial approaches. Immunotherapy and photodynamic therapy could be additional successful approaches particularly if developed in combination with chemotherapy for inoperable and metastatic BCCs. © 2017 Wiley Periodicals, Inc.

Influenza A Virus-Host Protein Interactions Control Viral Pathogenesis.

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Zhao, Mengmeng; Wang, Lingyan; Li, Shitao

2017-08-01

The influenza A virus (IAV), a member of the Orthomyxoviridae family, is a highly transmissible respiratory pathogen and represents a continued threat to global health with considerable economic and social impact. IAV is a zoonotic virus that comprises a plethora of strains with different pathogenic profiles. The different outcomes of viral pathogenesis are dependent on the engagement between the virus and the host cellular protein interaction network. The interactions may facilitate virus hijacking of host molecular machinery to fulfill the viral life cycle or trigger host immune defense to eliminate the virus. In recent years, much effort has been made to discover the virus-host protein interactions and understand the underlying mechanisms. In this paper, we review the recent advances in our understanding of IAV-host interactions and how these interactions contribute to host defense and viral pathogenesis.

Animal Models of Zika Virus Infection, Pathogenesis, and Immunity.

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Morrison, Thomas E; Diamond, Michael S

2017-04-15

Zika virus (ZIKV) is an emerging mosquito-transmitted flavivirus that now causes epidemics affecting millions of people on multiple continents. The virus has received global attention because of some of its unusual epidemiological and clinical features, including persistent infection in the male reproductive tract and sexual transmission, an ability to cross the placenta during pregnancy and infect the developing fetus to cause congenital malformations, and its association with Guillain-Barré syndrome in adults. This past year has witnessed an intensive effort by the global scientific community to understand the biology of ZIKV and to develop pathogenesis models for the rapid testing of possible countermeasures. Here, we review the recent advances in and utility and limitations of newly developed mouse and nonhuman primate models of ZIKV infection and pathogenesis. Copyright © 2017 American Society for Microbiology.

Pathogenesis of pulmonary emphysema – cellular and molecular events

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Antonio Di Petta

2010-06-01

Full Text Available Pulmonary emphysema is a chronic obstructive disease, resulting fromimportant alterations in the whole distal structure of terminal bronchioles, either by enlargement of air spaces or by destruction of the alveolar wall, leading to loss of respiratory surface, decreased elastic recoil and lung hyperinflation. For many years, the hypothesis of protease-antiprotease unbalance prevailed as the central theme in the pathogenesis of pulmonary emphysema. According to this hypothesis, the release of active proteolytic enzymes, produced mainly by neutrophils and macrophages, degrades the extracellular matrix, affecting the integrity of its components, especially collagen and elastic fibers. However, new concepts involving cellular and molecular events were proposed, including oxidative stress, cell apoptosis, cellular senescence and failed lung tissue repair. The aim of this review paper was to evaluate the cellular and molecular mechanisms seen in the pathogenesis of pulmonary emphysema.

miR-186 inhibits cell proliferation in multiple myeloma by repressing Jagged1

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Liu, Zengyan; Zhang, Guoqiang; Yu, Wenzheng; Gao, Na; Peng, Jun

2016-01-01

MicroRNAs (miRNAs) are small, noncoding ribonucleic acids that regulate gene expression by targeting mRNAs for translational repression and degradation. Accumulating experimental evidence supports a causal role of miRNAs in hematology tumorigenesis. However, the specific functions of miRNAs in the pathogenesis of multiple myeloma (MM) remain to be established. In this study, we demonstrated that miR-186 is commonly downregulated in MM cell lines and patient MM cells. Ectopic expression of miR-186 significantly inhibited cell growth, both in vitro and in vivo, and induced cell cycle G_0/G_1 arrest. Furthermore, miR-186 induced downregulation of Jagged1 protein expression by directly targeting its 3′-untranslated region (3′-UTR). Conversely, overexpression of Jagged1 rescued cells from miR-186-induced growth inhibition. Our collective results clearly indicate that miR-186 functions as a tumor suppressor in MM, supporting its potential as a therapeutic target for the disease. - Highlights: • miR-186 expression is decreased in MM. • miR-186 inhibits MM cell proliferation in vitro and in vivo. • Jagged1 is regulated by miR-186. • Overexpression of Jagged1 reverses the effects of miR-186.

miR-186 inhibits cell proliferation in multiple myeloma by repressing Jagged1

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Liu, Zengyan [Department of Hematology, Qilu Hospital, Shandong University, 107 Wenhuaxi Road, Jinan, Shandong 250012 (China); Department of Hematology, Hospital Affiliated to Binzhou Medical University, 661 Second Huanghe Street, Binzhou 256603 (China); Zhang, Guoqiang [Department of Thyroid and Breast Surgery, Hospital Affiliated to Binzhou Medical University, 661 Second Huanghe Street, Binzhou 256603 (China); Yu, Wenzheng; Gao, Na [Department of Hematology, Hospital Affiliated to Binzhou Medical University, 661 Second Huanghe Street, Binzhou 256603 (China); Peng, Jun, E-mail: junpeng885@sina.com [Department of Hematology, Qilu Hospital, Shandong University, 107 Wenhuaxi Road, Jinan, Shandong 250012 (China)

2016-01-15

MicroRNAs (miRNAs) are small, noncoding ribonucleic acids that regulate gene expression by targeting mRNAs for translational repression and degradation. Accumulating experimental evidence supports a causal role of miRNAs in hematology tumorigenesis. However, the specific functions of miRNAs in the pathogenesis of multiple myeloma (MM) remain to be established. In this study, we demonstrated that miR-186 is commonly downregulated in MM cell lines and patient MM cells. Ectopic expression of miR-186 significantly inhibited cell growth, both in vitro and in vivo, and induced cell cycle G{sub 0}/G{sub 1} arrest. Furthermore, miR-186 induced downregulation of Jagged1 protein expression by directly targeting its 3′-untranslated region (3′-UTR). Conversely, overexpression of Jagged1 rescued cells from miR-186-induced growth inhibition. Our collective results clearly indicate that miR-186 functions as a tumor suppressor in MM, supporting its potential as a therapeutic target for the disease. - Highlights: • miR-186 expression is decreased in MM. • miR-186 inhibits MM cell proliferation in vitro and in vivo. • Jagged1 is regulated by miR-186. • Overexpression of Jagged1 reverses the effects of miR-186.

Zinc binding activity of human metapneumovirus M2-1 protein is indispensable for viral replication and pathogenesis in vivo.

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Cai, Hui; Zhang, Yu; Ma, Yuanmei; Sun, Jing; Liang, Xueya; Li, Jianrong

2015-06-01

Human metapneumovirus (hMPV) is a member of the Pneumovirinae subfamily in the Paramyxoviridae family that causes respiratory tract infections in humans. Unlike members of the Paramyxovirinae subfamily, the polymerase complex of pneumoviruses requires an additional cofactor, the M2-1 protein, which functions as a transcriptional antitermination factor. The M2-1 protein was found to incorporate zinc ions, although the specific role(s) of the zinc binding activity in viral replication and pathogenesis remains unknown. In this study, we found that the third cysteine (C21) and the last histidine (H25) in the zinc binding motif (CCCH) of hMPV M2-1 were essential for zinc binding activity, whereas the first two cysteines (C7 and C15) play only minor or redundant roles in zinc binding. In addition, the zinc binding motif is essential for the oligomerization of M2-1. Subsequently, recombinant hMPVs (rhMPVs) carrying mutations in the zinc binding motif were recovered. Interestingly, rhMPV-C21S and -H25L mutants, which lacked zinc binding activity, had delayed replication in cell culture and were highly attenuated in cotton rats. In contrast, rhMPV-C7S and -C15S strains, which retained 60% of the zinc binding activity, replicated as efficiently as rhMPV in cotton rats. Importantly, rhMPVs that lacked zinc binding activity triggered high levels of neutralizing antibody and provided complete protection against challenge with rhMPV. Taken together, these results demonstrate that zinc binding activity is indispensable for viral replication and pathogenesis in vivo. These results also suggest that inhibition of zinc binding activity may serve as a novel approach to rationally attenuate hMPV and perhaps other pneumoviruses for vaccine purposes. The pneumoviruses include many important human and animal pathogens, such as human respiratory syncytial virus (hRSV), hMPV, bovine RSV, and avian metapneumovirus (aMPV). Among these viruses, hRSV and hMPV are the leading causes of acute

Inhibition of Histone Deacetylases Attenuates Morphine Tolerance and Restores MOR Expression in the DRG of BCP Rats

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Xiao-Tao He

2018-05-01

Full Text Available The easily developed morphine tolerance in bone cancer pain (BCP significantly hindered its clinical use. Increasing evidence suggests that histone deacetylases (HDACs regulate analgesic tolerance subsequent to continuous opioid exposure. However, whether HDACs contribute to morphine tolerance in the pathogenesis of BCP is still unknown. In the current study, we explored the possible engagement of HDACs in morphine tolerance during the pathogenesis of BCP. After intra-tibia tumor cell inoculation (TCI, we found that the increased expression of HDACs was negatively correlated with the decreased expression of MOR in the DRG following TCI. The paw withdrawal threshold (PWT and percentage maximum possible effects (MPEs decreased rapidly in TCI rats when morphine was used alone. In contrast, the concomitant use of SAHA and morphine significantly elevated the PWT and MPEs of TCI rats compared to morphine alone. Additionally, we found that SAHA administration significantly elevated MOR expression in the DRG of TCI rats with or without morphine treatment. Moreover, the TCI-induced increase in the co-expression of MOR and HDAC1 in neurons was significantly decreased after SAHA administration. These results suggest that HDACs are correlated with the downregulation of MOR in the DRG during the pathogenesis of BCP. Inhibition of HDACs using SAHA can be used to attenuate morphine tolerance in BCP.

Pathogenesis and pharmacologic treatment of obesity: the role of energy regulatory mechanism.

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Manulu, Mangatas S M; Sutanegara, I N Dwi

2006-01-01

Obesity has become a worldwide public health problem affecting millions of people. This is a chronic, stigmatized, and costly disease, rarely curable and is increasing in prevalence to a point today where we define obesity as an epidemic disease that not only in developed but also on developing countries. The pathogenesis of obesity is largely unknown, especially about energy regulatory mechanism that involved wide area of neuroendocrinology that is very interesting but very complex and makes internists "refuse" to learn. Obesity occurs through a longstanding imbalance between energy intake and energy expenditure, influenced by a complex biologic system that regulates appetite and adiposity. Obesity influences the pathogenesis of hypertension, type 2 diabetes, dyslipidemia, kidney, heart, and cerebrovascular disease. It is very wise for every internist to learn the pathogenesis and treatment of this worldwide diseases. Until now, the available treatments, including drugs, are palliative and are effective only while the treatment is being actively used; and besides so many side effects reported.

Molecular Pathogenesis of NASH

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Alessandra Caligiuri

2016-09-01

Full Text Available Nonalcoholic steatohepatitis (NASH is the main cause of chronic liver disease in the Western world and a major health problem, owing to its close association with obesity, diabetes, and the metabolic syndrome. NASH progression results from numerous events originating within the liver, as well as from signals derived from the adipose tissue and the gastrointestinal tract. In a fraction of NASH patients, disease may progress, eventually leading to advanced fibrosis, cirrhosis and hepatocellular carcinoma. Understanding the mechanisms leading to NASH and its evolution to cirrhosis is critical to identifying effective approaches for the treatment of this condition. In this review, we focus on some of the most recent data reported on the pathogenesis of NASH and its fibrogenic progression, highlighting potential targets for treatment or identification of biomarkers of disease progression.

Emotion modelling towards affective pathogenesis.

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Bas, James Le

2009-12-01

Objective: There is a need in psychiatry for models that integrate pathological states with normal systems. The interaction of arousal and emotion is the focus of an exploration of affective pathogenesis. Method: Given that the explicit causes of affective disorder remain nascent, methods of linking emotion and disorder are evaluated. Results: A network model of emotional families is presented, in which emotions exist as quantal gradients. Morbid emotional states are seen as the activation of distal emotion sites. The phenomenology of affective disorders is described with reference to this model. Recourse is made to non-linear dynamic theory. Conclusions: Metaphoric emotion models have face validity and may prove a useful heuristic.

[AETIOLOGY AND PATHOGENESIS GASTRO-DUODENALES ULCERATIVE LESIONS IN ELDERLY].

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Chernekhovskaya, N E; Povalayev, A V; Layshenko, G A

2015-01-01

In review today conceptions of view to aetiology and pathogenesis gastro-duodenales ulcerative lesions in elderly. Atherosclerosis, ischemic disease of the heart and hypertension are reasons of acute ulcers and erosions in elderly. The breaking of microcirculation are very importance.

Extrahepatic manifestations of cholestatic liver diseases: pathogenesis and therapy

NARCIS (Netherlands)

Pusl, Thomas; Beuers, Ulrich

2005-01-01

Pruritus, fatigue, and metabolic bone disease are frequent complications of cholestatic liver diseases, which can be quite distressing for the patient and can considerably reduce the quality of life. The molecular pathogenesis of these extrahepatic manifestations of cholestasis is poorly understood,

Osteoclast inhibition impairs chondrosarcoma growth and bone destruction.

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Otero, Jesse E; Stevens, Jeff W; Malandra, Allison E; Fredericks, Douglas C; Odgren, Paul R; Buckwalter, Joseph A; Morcuende, Jose

2014-12-01

Because Chondrosarcoma is resistant to available chemotherapy and radiation regimens, wide resection is the mainstay in treatment, which frequently results in high morbidity and which may not prevent local recurrence. There is a clear need for improved adjuvant treatment of this malignancy. We have observed the presence of osteoclasts in the microenvironment of chondrosarcoma in human pathological specimens. We utilized the Swarm rat chondrosarcoma (SRC) model to test the hypothesis that osteoclasts affect chondrosarcoma pathogenesis. We implanted SRC tumors in tibia of Sprague-Dawley rats and analyzed bone histologically and radiographically for bone destruction and tumor growth. At three weeks, tumors invaded local bone causing cortical disruption and trabecular resorption. Bone destruction was accompanied by increased osteoclast number and resorbed bone surface. Treatment of rats with the zoledronic acid prevented cortical destruction, inhibited trabecular resorption, and resulted in decreased tumor volume in bone. To confirm that inhibition of osteoclasts per se, and not off-target effects of drug, was responsible for the prevention of tumor growth and bone destruction, we implanted SRC into osteopetrotic rat tibia. SRC-induced bone destruction and tumor growth were impaired in osteopetrotic bone compared with control bone. The results from our animal model demonstrate that osteoclasts contribute to chondrosarcoma-mediated bone destruction and tumor growth and may represent a therapeutic target in particular chondrosarcoma patients. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Cell-cycle inhibition by Helicobacter pylori L-asparaginase.

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Claudia Scotti

Full Text Available Helicobacter pylori (H. pylori is a major human pathogen causing chronic gastritis, peptic ulcer, gastric cancer, and mucosa-associated lymphoid tissue lymphoma. One of the mechanisms whereby it induces damage depends on its interference with proliferation of host tissues. We here describe the discovery of a novel bacterial factor able to inhibit the cell-cycle of exposed cells, both of gastric and non-gastric origin. An integrated approach was adopted to isolate and characterise the molecule from the bacterial culture filtrate produced in a protein-free medium: size-exclusion chromatography, non-reducing gel electrophoresis, mass spectrometry, mutant analysis, recombinant protein expression and enzymatic assays. L-asparaginase was identified as the factor responsible for cell-cycle inhibition of fibroblasts and gastric cell lines. Its effect on cell-cycle was confirmed by inhibitors, a knockout strain and the action of recombinant L-asparaginase on cell lines. Interference with cell-cycle in vitro depended on cell genotype and was related to the expression levels of the concurrent enzyme asparagine synthetase. Bacterial subcellular distribution of L-asparaginase was also analysed along with its immunogenicity. H. pylori L-asparaginase is a novel antigen that functions as a cell-cycle inhibitor of fibroblasts and gastric cell lines. We give evidence supporting a role in the pathogenesis of H. pylori-related diseases and discuss its potential diagnostic application.

Myriocin significantly increases the mortality of a non-mammalian model host during Candida pathogenesis.

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Nadja Rodrigues de Melo

Full Text Available Candida albicans is a major human pathogen whose treatment is challenging due to antifungal drug toxicity, drug resistance and paucity of antifungal agents available. Myrocin (MYR inhibits sphingosine synthesis, a precursor of sphingolipids, an important cell membrane and signaling molecule component. MYR also has dual immune suppressive and antifungal properties, potentially modulating mammalian immunity and simultaneously reducing fungal infection risk. Wax moth (Galleria mellonella larvae, alternatives to mice, were used to establish if MYR suppressed insect immunity and increased survival of C. albicans-infected insects. MYR effects were studied in vivo and in vitro, and compared alone and combined with those of approved antifungal drugs, fluconazole (FLC and amphotericin B (AMPH. Insect immune defenses failed to inhibit C. albicans with high mortalities. In insects pretreated with the drug followed by C. albicans inoculation, MYR+C. albicans significantly increased mortality to 93% from 67% with C. albicans alone 48 h post-infection whilst AMPH+C. albicans and FLC+C. albicans only showed 26% and 0% mortalities, respectively. MYR combinations with other antifungal drugs in vivo also enhanced larval mortalities, contrasting the synergistic antifungal effect of the MYR+AMPH combination in vitro. MYR treatment influenced immunity and stress management gene expression during C. albicans pathogenesis, modulating transcripts putatively associated with signal transduction/regulation of cytokines, I-kappaB kinase/NF-kappaB cascade, G-protein coupled receptor and inflammation. In contrast, all stress management gene expression was down-regulated in FLC and AMPH pretreated C. albicans-infected insects. Results are discussed with their implications for clinical use of MYR to treat sphingolipid-associated disorders.

Genome-wide association studies on HIV susceptibility, pathogenesis and pharmacogenomics

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van Manen Daniëlle

2012-08-01

Full Text Available Abstract Susceptibility to HIV-1 and the clinical course after infection show a substantial heterogeneity between individuals. Part of this variability can be attributed to host genetic variation. Initial candidate gene studies have revealed interesting host factors that influence HIV infection, replication and pathogenesis. Recently, genome-wide association studies (GWAS were utilized for unbiased searches at a genome-wide level to discover novel genetic factors and pathways involved in HIV-1 infection. This review gives an overview of findings from the GWAS performed on HIV infection, within different cohorts, with variable patient and phenotype selection. Furthermore, novel techniques and strategies in research that might contribute to the complete understanding of virus-host interactions and its role on the pathogenesis of HIV infection are discussed.

Estrogen signalling in the pathogenesis of age-related macular degeneration.

Science.gov (United States)

Kaarniranta, Kai; Machalińska, Anna; Veréb, Zoltán; Salminen, Antero; Petrovski, Goran; Kauppinen, Anu

2015-02-01

Age-related macular degeneration (AMD) is a multifactorial eye disease that is associated with aging, family history, smoking, obesity, cataract surgery, arteriosclerosis, hypertension, hypercholesterolemia and unhealthy diet. Gender has commonly been classified as a weak or inconsistent risk factor for AMD. This disease is characterized by degeneration of retinal pigment epithelial (RPE) cells, Bruch's membrane, and choriocapillaris, which secondarily lead to damage and death of photoreceptor cells and central visual loss. Pathogenesis of AMD involves constant oxidative stress, chronic inflammation, and increased accumulation of lipofuscin and drusen. Estrogen has both anti-oxidative and anti-inflammatory capacity and it regulates signaling pathways that are involved in the pathogenesis of AMD. In this review, we discuss potential cellular signaling targets of estrogen in retinal cells and AMD pathology.

Critical role of environmental factors in the pathogenesis of psoriasis.

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Zeng, Jinrong; Luo, Shuaihantian; Huang, Yumeng; Lu, Qianjin

2017-08-01

Psoriasis is a common cutaneous disease with multifactorial etiology including genetic and non-genetic factors, such as drugs, smoking, drinking, diet, infection and mental stress. Now, the role of the interaction between environmental factors and genetics are considered to be a main factor in the pathogenesis of psoriasis. However, it is a challenge to explore the mechanisms how the environmental factors break the body balance to affect the onset and development of psoriasis. In this article, we review the pathogenesis of psoriasis and summarize numerous clinical data to reveal the association between environmental factors and psoriasis. In addition, we focus on the mechanisms of environmental risk factors impact on psoriasis and provide a series of potential treatments against environmental risk factors. © 2017 Japanese Dermatological Association.

Structural basis of kynurenine 3-monooxygenase inhibition.

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Amaral, Marta; Levy, Colin; Heyes, Derren J; Lafite, Pierre; Outeiro, Tiago F; Giorgini, Flaviano; Leys, David; Scrutton, Nigel S

2013-04-18

Inhibition of kynurenine 3-monooxygenase (KMO), an enzyme in the eukaryotic tryptophan catabolic pathway (that is, kynurenine pathway), leads to amelioration of Huntington's-disease-relevant phenotypes in yeast, fruitfly and mouse models, as well as in a mouse model of Alzheimer's disease. KMO is a flavin adenine dinucleotide (FAD)-dependent monooxygenase and is located in the outer mitochondrial membrane where it converts l-kynurenine to 3-hydroxykynurenine. Perturbations in the levels of kynurenine pathway metabolites have been linked to the pathogenesis of a spectrum of brain disorders, as well as cancer and several peripheral inflammatory conditions. Despite the importance of KMO as a target for neurodegenerative disease, the molecular basis of KMO inhibition by available lead compounds has remained unknown. Here we report the first crystal structure of Saccharomyces cerevisiae KMO, in the free form and in complex with the tight-binding inhibitor UPF 648. UPF 648 binds close to the FAD cofactor and perturbs the local active-site structure, preventing productive binding of the substrate l-kynurenine. Functional assays and targeted mutagenesis reveal that the active-site architecture and UPF 648 binding are essentially identical in human KMO, validating the yeast KMO-UPF 648 structure as a template for structure-based drug design. This will inform the search for new KMO inhibitors that are able to cross the blood-brain barrier in targeted therapies against neurodegenerative diseases such as Huntington's, Alzheimer's and Parkinson's diseases.

Protein Arginine Methyltransferase 5 Inhibition Upregulates Foxp3+ Regulatory T Cells Frequency and Function during the Ulcerative Colitis

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Yingxia Zheng

2017-05-01

Full Text Available Ulcerative colitis (UC pathogenesis is related to imbalance of immune responses, and the equilibrium between inflammatory T cells and Foxp3+ regulatory T cells (Tregs plays an important role in the intestinal homeostasis. Protein arginine methyltransferases (PRMTs regulate chromatin remodeling and gene expression. Here, we investigated whether inhibition of PRMTs affects colitis pathogenesis in mice and inflammatory bowel disease patients and further explored the underlying mechanisms. In this study, we found that protein arginine N-methyltransferase inhibitor 1 (AMI-1 treatments increased Tregs frequency, function, and reduced colitis incidence. Adoptive transfer of AMI-1-treated Tregs could reduce the colitis incidence. Colitis was associated with increased local PRMT5 expression, which was inhibited by AMI-1 treatment. Additionally, PRMT5 knockdown T cells produced a better response to TGFβ and promoted Tregs differentiation through decreased DNA methyltransferase 1 (DNMT1 expression. PRMT5 also enhanced H3K27me3 and DNMT1 binding to Foxp3 promoter, which restricted Tregs differentiation. Furthermore, PRMT5 knockdown led to decreased Foxp3 promoter methylation during Tregs induction. PRMT5 expression had a negative relationship with Tregs in UC patients, knockdown of PRMT5 expression increased Tregs frequency and decreased TNFα, IL-6, and IL-13 levels. Our study outlines a novel regulation of PRMT5 on Tregs development and function. Strategies to decrease PRMT5 expression might have therapeutic potential to control UC.

Antipsychotics, chlorpromazine and haloperidol inhibit voltage-gated proton currents in BV2 microglial cells.

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Shin, Hyewon; Song, Jin-Ho

2014-09-05

Microglial dysfunction and neuroinflammation are thought to contribute to the pathogenesis of schizophrenia. Some antipsychotic drugs have anti-inflammatory activity and can reduce the secretion of pro-inflammatory cytokines and reactive oxygen species from activated microglial cells. Voltage-gated proton channels on the microglial cells participate in the generation of reactive oxygen species and neuronal toxicity by supporting NADPH oxidase activity. In the present study, we examined the effects of two typical antipsychotics, chlorpromazine and haloperidol, on proton currents in microglial BV2 cells using the whole-cell patch clamp method. Chlorpromazine and haloperidol potently inhibited proton currents with IC50 values of 2.2 μM and 8.4 μM, respectively. Chlorpromazine and haloperidol are weak bases that can increase the intracellular pH, whereby they reduce the proton gradient and affect channel gating. Although the drugs caused a marginal positive shift of the activation voltage, they did not change the reversal potential. This suggested that proton current inhibition was not due to an alteration of the intracellular pH. Chlorpromazine and haloperidol are strong blockers of dopamine receptors. While dopamine itself did not affect proton currents, it also did not alter proton current inhibition by the two antipsychotics, indicating dopamine receptors are not likely to mediate the proton current inhibition. Given that proton channels are important for the production of reactive oxygen species and possibly pro-inflammatory cytokines, the anti-inflammatory and antipsychotic activities of chlorpromazine and haloperidol may be partly derived from their ability to inhibit microglial proton currents. Copyright © 2014 Elsevier B.V. All rights reserved.

Diabetic polyneuropathy: pathogenesis, classification, clinical presentation, and treatment

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Marina Valentinovna Nesterova

2013-01-01

Full Text Available Diabetes mellitus (DM is a global epidemic followed by late complications as diabetic polyneuropathy (DPN and diabetic foot syndrome, leading to appreciable social and economic consequences. Virtually all patients with DM develop DPN in different periods. There is a clear correlation between the presence and magnitude of painful DPN and the duration of DM and the level of glycosylated hemoglobin and the severity of DPN. In spite of the abundance of theories of the development of DPN, its main identified pathogenetic factor is hyperglycemia. The literature gives no universal classification due to the variability of clinical symptoms. The main goals of treatment are to affect the pathogenesis of the disease and to prescribe symptomatic medications. The pathogenetic treatment of DPN includes compensation for carbohydrate metabolism and use of neurometabolic drugs. Pain from DPN may be controlled with antidepressants, anticonvulsants, local anesthetics and opioid analgesics. Although much evidence for the pathogenesis of peripheral nervous system injury has been recently accumulated, a universal standard for the effective therapy of DPN and the follow-up of these patients has not yet been developed.

The roles of environmental pollutants in the pathogenesis and ...

African Journals Online (AJOL)

... rise worldwide with a growing suspicion of association between environmental pollutants and diabetes. This paper reviewed the roles of environmental pollutants in the pathogenesis and increasing incidence of diabetes. Relevant information was retrieved from reliable sources in the internet using Google search engine.

[Neurosis and genetic theory of etiology and pathogenesis of ulcer disease].

Science.gov (United States)

Kolotilova, M L; Ivanov, L N

2014-01-01

Based on the analysis of literature data and our own research, we have developed the original concept of etiology and pathogenesis of peptic ulcer disease. An analysis of the literature shows that none of the theories of pathogenesis of peptic ulcer disease does not cover the full diversity of the involved functions and their shifts, which lead to the development of ulcers in the stomach and the duodenum. Our neurogenic-genetic theory of etiology and pathogenesis of gastric ulcer and duodenal ulcer very best explains the cause-and-effect relationships in the patient peptic ulcer, allowing options for predominance in one or the other case factors of neurosis or genetic factors. However, it is clear that the only other: combination of neurogenic factor with genetically modified reactivity of gastroduodenal system (the presence of the target organ) cause the chronicity of the sores. The theory of peptic ulcer disease related to psychosomatic pathologies allows us to develop effective schema therapy, including drugs with psychocorrective action. On the basis of our theory of the role of Helicobacter pylori infection is treated as a pathogenetic factor in the development of peptic ulcer disease.

Citric acid inhibits development of cataracts, proteinuria and ketosis in streptozotocin (type1) diabetic rats

Science.gov (United States)

Nagai, Ryoji; Nagai, Mime; Shimasaki, Satoko; Baynes, John W.; Fujiwara, Yukio

2010-01-01

Although many fruits such as lemon and orange contain citric acid, little is known about beneficial effects of citric acid on health. Here we measured the effect of citric acid on the pathogenesis of diabetic complications in streptozotocin-induced diabetic rats. Although oral administration of citric acid to diabetic rats did not affect blood glucose concentration, it delayed the development of cataracts, inhibited accumulation of advanced glycation end products (AGEs) such as Nε-(carboxyethyl)lysine (CEL) and Nε-(carboxymethyl)lysine (CML) in lens proteins, and protected against albuminuria and ketosis . We also show that incubation of protein with acetol, a metabolite formed from acetone by acetone monooxygenase, generate CEL, suggesting that inhibition of ketosis by citric acid may lead to the decrease in CEL in lens proteins. These results demonstrate that the oral administration of citric acid ameliorates ketosis and protects against the development of diabetic complications in an animal model of type 1 diabetes. PMID:20117096

Allicin from garlic inhibits the biofilm formation and urease activity of Proteus mirabilis in vitro.

Science.gov (United States)

Ranjbar-Omid, Mahsa; Arzanlou, Mohsen; Amani, Mojtaba; Shokri Al-Hashem, Seyyedeh Khadijeh; Amir Mozafari, Nour; Peeri Doghaheh, Hadi

2015-05-01

Several virulence factors contribute to the pathogenesis of Proteus mirabilis. This study determined the inhibitory effects of allicin on urease, hemolysin and biofilm of P. mirabilis ATCC 12453 and its antimicrobial activity against 20 clinical isolates of P. mirabilis. Allicin did not inhibit hemolysin, whereas it did inhibit relative urease activity in both pre-lysed (half-maximum inhibitory concentration, IC50 = 4.15 μg) and intact cells (IC50 = 21 μg) in a concentration-dependent manner. Allicin at sub-minimum inhibitory concentrations (2-32 μg mL(-1)) showed no significant effects on the growth of the bacteria (P > 0.05), but it reduced biofilm development in a concentration-dependent manner (P mirabilis isolates were determined to be 128 and 512 μg mL(-1), respectively. The results suggest that allicin could have clinical applications in controlling P. mirabilis infections. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Inhibition of nuclear factor-kappa B activation decreases survival of Mycobacterium tuberculosis in human macrophages.

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Xiyuan Bai

Full Text Available Nuclear factor-kappa B (NFκB is a ubiquitous transcription factor that mediates pro-inflammatory responses required for host control of many microbial pathogens; on the other hand, NFκB has been implicated in the pathogenesis of other inflammatory and infectious diseases. Mice with genetic disruption of the p50 subunit of NFκB are more likely to succumb to Mycobacterium tuberculosis (MTB. However, the role of NFκB in host defense in humans is not fully understood. We sought to examine the role of NFκB activation in the immune response of human macrophages to MTB. Targeted pharmacologic inhibition of NFκB activation using BAY 11-7082 (BAY, an inhibitor of IκBα kinase or an adenovirus construct with a dominant-negative IκBα significantly decreased the number of viable intracellular mycobacteria recovered from THP-1 macrophages four and eight days after infection. The results with BAY were confirmed in primary human monocyte-derived macrophages and alveolar macrophages. NFκB inhibition was associated with increased macrophage apoptosis and autophagy, which are well-established killing mechanisms of intracellular MTB. Inhibition of the executioner protease caspase-3 or of the autophagic pathway significantly abrogated the effects of BAY. We conclude that NFκB inhibition decreases viability of intracellular MTB in human macrophages via induction of apoptosis and autophagy.

The H.E.S.S. Galactic plane survey

Science.gov (United States)

H. E. S. S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Benkhali, F. Ait; Angüner, E. O.; Arakawa, M.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Tjus, J. Becker; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bonnefoy, S.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Büchele, M.; Bulik, T.; Capasso, M.; Carrigan, S.; Caroff, S.; Carosi, A.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Colafrancesco, S.; Condon, B.; Conrad, J.; Davids, I. D.; Decock, J.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'C.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Emery, G.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gallant, Y. A.; Garrigoux, T.; Gast, H.; Gaté, F.; Giavitto, G.; Giebels, B.; Glawion, D.; Glicenstein, J. F.; Gottschall, D.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holch, T. L.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khélifi, B.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Malyshev, D.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Ndiyavala, H.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Paz Arribas, M.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poireau, V.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Rauth, R.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Rieger, F.; Rinchiuso, L.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Safi-Harb, S.; Sahakian, V.; Saito, S.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schandri, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Shiningayamwe, K.; Simoni, R.; Sol, H.; Spanier, F.; Spir-Jacob, M.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Steppa, C.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsirou, M.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Zorn, J.; Żywucka, N.

2018-04-01

We present the results of the most comprehensive survey of the Galactic plane in very high-energy (VHE) γ-rays, including a public release of Galactic sky maps, a catalog of VHE sources, and the discovery of 16 new sources of VHE γ-rays. The High Energy Spectroscopic System (H.E.S.S.) Galactic plane survey (HGPS) was a decade-long observation program carried out by the H.E.S.S. I array of Cherenkov telescopes in Namibia from 2004 to 2013. The observations amount to nearly 2700 h of quality-selected data, covering the Galactic plane at longitudes from ℓ = 250° to 65° and latitudes |b|≤ 3°. In addition to the unprecedented spatial coverage, the HGPS also features a relatively high angular resolution (0.08° ≈ 5 arcmin mean point spread function 68% containment radius), sensitivity (≲1.5% Crab flux for point-like sources), and energy range (0.2-100 TeV). We constructed a catalog of VHE γ-ray sources from the HGPS data set with a systematic procedure for both source detection and characterization of morphology and spectrum. We present this likelihood-based method in detail, including the introduction of a model component to account for unresolved, large-scale emission along the Galactic plane. In total, the resulting HGPS catalog contains 78 VHE sources, of which 14 are not reanalyzed here, for example, due to their complex morphology, namely shell-like sources and the Galactic center region. Where possible, we provide a firm identification of the VHE source or plausible associations with sources in other astronomical catalogs. We also studied the characteristics of the VHE sources with source parameter distributions. 16 new sources were previously unknown or unpublished, and we individually discuss their identifications or possible associations. We firmly identified 31 sources as pulsar wind nebulae (PWNe), supernova remnants (SNRs), composite SNRs, or gamma-ray binaries. Among the 47 sources not yet identified, most of them (36) have possible

MicroRNA-99a inhibits insulin-induced proliferation, migration, dedifferentiation, and rapamycin resistance of vascular smooth muscle cells by inhibiting insulin-like growth factor-1 receptor and mammalian target of rapamycin

International Nuclear Information System (INIS)

Zhang, Zi-wei; Guo, Rui-wei; Lv, Jin-lin; Wang, Xian-mei; Ye, Jin-shan; Lu, Ni-hong; Liang, Xing; Yang, Li-xia

2017-01-01

Patients with type 2 diabetes mellitus (T2DM) are characterized by insulin resistance and are subsequently at high risk for atherosclerosis. Hyperinsulinemia has been associated with proliferation, migration, and dedifferentiation of vascular smooth muscle cells (VSMCs) during the pathogenesis of atherosclerosis. Moreover, insulin-like growth factor-1 receptor (IGF-1R) and mammalian target of rapamycin (mTOR) have been demonstrated to be the underlying signaling pathways. Recently, microRNA-99a (miR-99a) has been suggested to regulate the phenotypic changes of VSMCs in cancer cells. However, whether it is involved in insulin-induced changes of VSCMs has not been determined. In this study, we found that insulin induced proliferation, migration, and dedifferentiation of mouse VSMCs in a dose-dependent manner. Furthermore, the stimulating effects of high-dose insulin on proliferation, migration, and dedifferentiation of mouse VSMCs were found to be associated with the attenuation of the inhibitory effects of miR-99a on IGF-1R and mTOR signaling activities. Finally, we found that the inducing effect of high-dose insulin on proliferation, migration, and dedifferentiation of VSMCs was partially inhibited by an active mimic of miR-99a. Taken together, these results suggest that miR-99a plays a key regulatory role in the pathogenesis of insulin-induced proliferation, migration, and phenotype conversion of VSMCs at least partly via inhibition of IGF-1R and mTOR signaling. Our results provide evidence that miR-99a may be a novel target for the treatment of hyperinsulinemia-induced atherosclerosis. - Highlights: • Suggesting a new mechanism of insulin-triggered VSMC functions. • Providing a new therapeutic strategies that target atherosclerosis in T2DM patients. • Providing a new strategies that target in-stent restenosis in T2DM patients.

Structural studies of human glioma pathogenesis-related protein 1

Energy Technology Data Exchange (ETDEWEB)

Asojo, Oluwatoyin A., E-mail: oasojo@unmc.edu [College of Medicine, Nebraska Medical Center, Omaha, NE 68198-6495 (United States); Koski, Raymond A.; Bonafé, Nathalie [L2 Diagnostics LLC, 300 George Street, New Haven, CT 06511 (United States); College of Medicine, Nebraska Medical Center, Omaha, NE 68198-6495 (United States)

2011-10-01

Structural analysis of a truncated soluble domain of human glioma pathogenesis-related protein 1, a membrane protein implicated in the proliferation of aggressive brain cancer, is presented. Human glioma pathogenesis-related protein 1 (GLIPR1) is a membrane protein that is highly upregulated in brain cancers but is barely detectable in normal brain tissue. GLIPR1 is composed of a signal peptide that directs its secretion, a conserved cysteine-rich CAP (cysteine-rich secretory proteins, antigen 5 and pathogenesis-related 1 proteins) domain and a transmembrane domain. GLIPR1 is currently being investigated as a candidate for prostate cancer gene therapy and for glioblastoma targeted therapy. Crystal structures of a truncated soluble domain of the human GLIPR1 protein (sGLIPR1) solved by molecular replacement using a truncated polyalanine search model of the CAP domain of stecrisp, a snake-venom cysteine-rich secretory protein (CRISP), are presented. The correct molecular-replacement solution could only be obtained by removing all loops from the search model. The native structure was refined to 1.85 Å resolution and that of a Zn{sup 2+} complex was refined to 2.2 Å resolution. The latter structure revealed that the putative binding cavity coordinates Zn{sup 2+} similarly to snake-venom CRISPs, which are involved in Zn{sup 2+}-dependent mechanisms of inflammatory modulation. Both sGLIPR1 structures have extensive flexible loop/turn regions and unique charge distributions that were not observed in any of the previously reported CAP protein structures. A model is also proposed for the structure of full-length membrane-bound GLIPR1.

Urinary Tract Infection: Pathogenesis and Outlook

Science.gov (United States)

McLellan, Lisa K.; Hunstad, David A.

2016-01-01

The clinical syndromes comprising urinary tract infection (UTI) continue to exert significant impact on millions of patients worldwide, most of whom are otherwise healthy women. Antibiotic therapy for acute cystitis does not prevent recurrences, which plague up to one fourth of women after an initial UTI. Rising antimicrobial resistance among uropathogenic bacteria further complicates therapeutic decisions, necessitating new approaches based on fundamental biological investigation. In this review, we highlight contemporary advances in the field of UTI pathogenesis and how these might inform both our clinical perspective and future scientific priorities. PMID:27692880

Caspase-9 mediates synaptic plasticity and memory deficits of Danish dementia knock-in mice: caspase-9 inhibition provides therapeutic protection

Directory of Open Access Journals (Sweden)

Tamayev Robert

2012-12-01

Full Text Available Abstract Background Mutations in either Aβ Precursor protein (APP or genes that regulate APP processing, such as BRI2/ITM2B and PSEN1/PSEN2, cause familial dementias. Although dementias due to APP/PSEN1/PSEN2 mutations are classified as familial Alzheimer disease (FAD and those due to mutations in BRI2/ITM2B as British and Danish dementias (FBD, FDD, data suggest that these diseases have a common pathogenesis involving toxic APP metabolites. It was previously shown that FAD mutations in APP and PSENs promote activation of caspases leading to the hypothesis that aberrant caspase activation could participate in AD pathogenesis. Results Here, we tested whether a similar mechanism applies to the Danish BRI2/ITM2B mutation. We have generated a genetically congruous mouse model of FDD, called FDDKI, which presents memory and synaptic plasticity deficits. We found that caspase-9 is activated in hippocampal synaptic fractions of FDDKI mice and inhibition of caspase-9 activity rescues both synaptic plasticity and memory deficits. Conclusion These data directly implicate caspase-9 in the pathogenesis of Danish dementia and suggest that reducing caspase-9 activity is a valid therapeutic approach to treating human dementias.

Inhibition of HDAC6 protects against rhabdomyolysis-induced acute kidney injury.

Science.gov (United States)

Shi, Yingfeng; Xu, Liuqing; Tang, Jinhua; Fang, Lu; Ma, Shuchen; Ma, Xiaoyan; Nie, Jing; Pi, Xiaoling; Qiu, Andong; Zhuang, Shougang; Liu, Na

2017-03-01

Histone deacetylase 6 (HDAC6) inhibition has been reported to protect against ischemic stroke and prolong survival after sepsis in animal models. However, it remains unknown whether HDAC6 inhibition offers a renoprotective effect after acute kidney injury (AKI). In this study, we examined the effect of tubastatin A (TA), a highly selective inhibitor of HDAC6, on AKI in a murine model of glycerol (GL) injection-induced rhabdomyolysis. Following GL injection, the mice developed severe acute tubular injury as indicated by renal dysfunction; expression of neutrophil gelatinase-associated lipocalin (NGAL), an injury marker of renal tubules; and an increase of TdT-mediated dUTP nick-end labeling (TUNEL)-positive tubular cells. These changes were companied by increased HDAC6 expression in the cytoplasm of renal tubular cells. Administration of TA significantly reduced serum creatinine and blood urea nitrogen levels as well as attenuated renal tubular damage in injured kidneys. HDAC6 inhibition also resulted in decreased expression of NGAL, reduced apoptotic cell, and inactivated caspase-3 in the kidney after acute injury. Moreover, injury to the kidney increased phosphorylation of nuclear factor (NF)-κB and expression of multiple cytokines/chemokines including tumor necrotic factor-α and interleukin-6 and monocyte chemoattractant protein-1, as well as macrophage infiltration. Treatment with TA attenuated all those responses. Finally, HDAC6 inhibition reduced the level of oxidative stress by suppressing malondialdehyde (MDA) and preserving expression of superoxide dismutase (SOD) in the injured kidney. Collectively, these data indicate that HDAC6 contributes to the pathogenesis of rhabdomyolysis-induced AKI and suggest that HDAC6 inhibitors have therapeutic potential for AKI treatment. Copyright © 2017 the American Physiological Society.

Myeloid DLL4 Does Not Contribute to the Pathogenesis of Non-Alcoholic Steatohepatitis in Ldlr-/- Mice.

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Mike L J Jeurissen

Full Text Available Non-alcoholic steatohepatitis (NASH is characterized by liver steatosis and inflammation. Currently, the underlying mechanisms leading to hepatic inflammation are not fully understood and consequently, therapeutic options are poor. Non-alcoholic steatohepatitis (NASH and atherosclerosis share the same etiology whereby macrophages play a key role in disease progression. Macrophage function can be modulated via activation of receptor-ligand binding of Notch signaling. Relevantly, global inhibition of Notch ligand Delta-Like Ligand-4 (DLL4 attenuates atherosclerosis by altering the macrophage-mediated inflammatory response. However, the specific contribution of macrophage DLL4 to hepatic inflammation is currently unknown. We hypothesized that myeloid DLL4 deficiency in low-density lipoprotein receptor knock-out (Ldlr-/- mice reduces hepatic inflammation. Irradiated Ldlr-/- mice were transplanted (tp with bone marrow from wild type (Wt or DLL4f/fLysMCre+/0 (DLL4del mice and fed either chow or high fat, high cholesterol (HFC diet for 11 weeks. Additionally, gene expression was assessed in bone marrow-derived macrophages (BMDM of DLL4f/fLysMCreWT and DLL4f/fLysMCre+/0 mice. In contrast to our hypothesis, inflammation was not decreased in HFC-fed DLL4del-transplanted mice. In line, in vitro, there was no difference in the expression of inflammatory genes between DLL4-deficient and wildtype bone marrow-derived macrophages. These results suggest that myeloid DLL4 deficiency does not contribute to hepatic inflammation in vivo. Since, macrophage-DLL4 expression in our model was not completely suppressed, it can't be totally excluded that complete DLL4 deletion in macrophages might lead to different results. Nevertheless, the contribution of non-myeloid Kupffer cells to notch signaling with regard to the pathogenesis of steatohepatitis is unknown and as such it is possible that, DLL4 on Kupffer cells promote the pathogenesis of steatohepatitis.

The potential implication of eosinophil activation in the pathogenesis ...

African Journals Online (AJOL)

Ehab

The potential implication of eosinophil activation in the pathogenesis of childhood asthma. INTRODUCTION. Asthma is recognized as an eosinophil mediated inflammation of the airways1. Eosinophils are major contributors to the damage in the airways of asthmatic patients which when activated, degranulate and release ...

NEW DEVELOPMENTS IN THE PATHOGENESIS OF PREECLAMPSIA

OpenAIRE

Naljayan, Mihran V.; Karumanchi, S. Ananth

2013-01-01

Preeclampsia affecting 3-5% of all pregnancies is a major cause of maternal and perinatal morbidity and mortality worldwide. This disorder is characterized by a constellation of signs and symptoms, most notably new onset hypertension and proteinuria during the last trimester of pregnancy. In this review, the molecular mechanisms of preeclampsia with an emphasis on the role of circulating anti-angiogenic proteins in the pathogenesis of preeclampsia and its complications will be discussed.

Selective inhibition of prostaglandin E2 receptors EP2 and EP4 inhibits adhesion of human endometriotic epithelial and stromal cells through suppression of integrin-mediated mechanisms.

Science.gov (United States)

Lee, JeHoon; Banu, Sakhila K; Burghardt, Robert C; Starzinski-Powitz, Anna; Arosh, Joe A

2013-03-01

Endometriosis is a chronic gynecological disease of reproductive age women characterized by the presence of functional endometrial tissues outside the uterine cavity. Interactions between the endometriotic cells and the peritoneal extracellular matrix proteins (ECM) are crucial mechanisms that allow adhesion of the endometriotic cells into peritoneal mesothelia. Prostaglandin E2 (PGE2) plays an important role in the pathogenesis of endometriosis. In previous studies, we have reported that selective inhibition of PGE2 receptors PTGER2 and PTGER4 decreases survival and invasion of human endometriotic epithelial and stromal cells through multiple mechanisms. Results of the present study indicates that selective inhibition of PTGER2- and PTGER4-mediated PGE2 signaling 1) decreases the expression and/or activity of specific integrin receptor subunits Itgb1 (beta1) and Itgb3 (beta3) but not Itgb5 (beta5), Itga1 (alpha1), Itga2 (alpha2), Itga5 (alpha5), and Itgav (alphav); 2) decreases integrin-signaling components focal adhesion kinase or protein kinase 2 (PTK2) and talin proteins; 3) inhibits interactions between Itgb1/Itgb3 subunits, PTK2, and talin and PTGER2/PTGER4 proteins through beta-arrestin-1 and Src kinase protein complex in human endometriotic epithelial cells 12Z and stromal cells 22B; and 4) decreases adhesion of 12Z and 22B cells to ECM collagen I, collagen IV, fibronectin, and vitronectin in a substrate-specific manner. These novel findings provide an important molecular framework for further evaluation of selective inhibition of PTGER2 and PTGER4 as potential nonsteroidal therapy to expand the spectrum of currently available treatment options for endometriosis in child-bearing age women.

Molecular pathogenesis of hepatocellular carcinoma and impact of therapeutic advances

Science.gov (United States)

Dhanasekaran, Renumathy; Bandoh, Salome; Roberts, Lewis R.

2016-01-01

Hepatocellular carcinoma (HCC) is a leading cause of cancer mortality and has an increasing incidence worldwide. HCC can be induced by multiple etiologies, is influenced by many risk factors, and has a complex pathogenesis. Furthermore, HCCs exhibit substantial heterogeneity, which compounds the difficulties in developing effective therapies against this highly lethal cancer. With advances in cancer biology and molecular and genetic profiling, a number of different mechanisms involved in the development and progression of HCC have been identified. Despite the advances in this area, the molecular pathogenesis of hepatocellular carcinoma is still not completely understood. This review aims to elaborate our current understanding of the most relevant genetic alterations and molecular pathways involved in the development and progression of HCC, and anticipate the potential impact of future advances on therapeutic drug development. PMID:27239288

Recovery of active pathogenesis-related enzymes from the apoplast ...

African Journals Online (AJOL)

Overall protease activity intensity was higher in the symplast. Maximum symplast contamination of the apoplast was 2% as estimated by glucose 6-phosphate dehydrogenase activity, a biochemical marker for symplast. Accumulation of pathogenesis-related enzymatic activities in the apoplast of M. acuminata leaf tissue was ...

The puzzle of polymorphous light eruption : Patients and pathogenesis

NARCIS (Netherlands)

Schornagel, I.J.

2007-01-01

Polymorphous light eruption (PLE) is a photosensitivity disorder of which the pathogenesis is not fully understood. Patient history in PLE is important since lesions are transient and often not present at time of consultation. Phototesting is done to reproduce the PLE skin lesions and to obtain

HIV Infection of Macrophages: Implications for Pathogenesis and Cure

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Kiera Leigh Clayton

2017-05-01

Full Text Available Although CD4+ T cells represent the major reservoir of persistent HIV and SIV infection, accumulating evidence suggests that macrophages also contribute. However, investigations of the role of macrophages are often underrepresented at HIV pathogenesis and cure meetings. This was the impetus for a scientific workshop dedicated to this area of study, held in Cambridge, MA in January 2017. The workshop brought together experts in the fields of HIV/SIV immunology/virology, macrophage biology and immunology, and animal models of HIV/SIV infection to facilitate discussions regarding the role of macrophages as a physiologically relevant viral reservoir, and the implications of macrophage infection for HIV pathogenesis and cure strategies. An emerging consensus that infected macrophages likely persist in the setting of combination antiretroviral therapy, driving persistent inflammation and contributing to the viral reservoir, indicate the importance of addressing macrophages as well as CD4+ T cells with future therapeutic strategies.

Genetic determinants of pathogenesis by feline infectious peritonitis virus.

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Brown, Meredith A

2011-10-15

Feline infectious peritonitis (FIP) is a fatal, immune-augmented, and progressive viral disease of cats associated with feline coronavirus (FCoV). Viral genetic determinants specifically associated with FIPV pathogenesis have not yet been discovered. Viral gene signatures in the spike, non-structural protein 3c, and membrane of the coronavirus genome have been shown to often correlate with disease manifestation. An "in vivo mutation transition hypothesis" is widely accepted and postulates that de novo virus mutation occurs in vivo giving rise to virulence. The existence of "distinct circulating avirulent and virulent strains" is an alternative hypothesis of viral pathogenesis. It may be possible that viral dynamics from both hypotheses are at play in the occurrence of FIP. Epidemiologic data suggests that the genetic background of the cat contributes to the manifestation of FIP. Further studies exploring both viral and host genetic determinants of disease in FIP offer specific opportunities for the management of this disease. Copyright © 2011 Elsevier B.V. All rights reserved.

New discoveries in the pathogenesis and classification of vitiligo.

Science.gov (United States)

Rodrigues, Michelle; Ezzedine, Khaled; Hamzavi, Iltefat; Pandya, Amit G; Harris, John E

2017-07-01

Vitiligo is a common autoimmune disease that progressively destroys melanocytes in the skin, resulting in the appearance of patchy depigmentation. This disfiguring condition frequently affects the face and other visible areas of the body, which can be psychologically devastating. The onset of vitiligo often occurs in younger individuals and progresses for life, resulting in a heavy burden of disease and decreased quality of life. Presentation patterns of vitiligo vary, and recognition of these patterns provides both diagnostic and prognostic clues. Recent insights into disease pathogenesis offer a better understanding of the natural history of the disease, its associations, and potential for future treatments. The first article in this continuing medical education series outlines typical and atypical presentations of vitiligo, how they reflect disease activity, prognosis, and response to treatment. Finally, we discuss disease associations, risk factors, and our current understanding of disease pathogenesis. Copyright © 2016 American Academy of Dermatology, Inc. All rights reserved.

Tubuloreticular structures in different types of myositis: implications for pathogenesis

NARCIS (Netherlands)

Bronner, Irene M.; Hoogendijk, Jessica E.; Veldman, Henk; Ramkema, Marja; van den Bergh Weerman, Marius A.; Rozemuller, Annemieke J. M.; de Visser, Marianne

2008-01-01

In dermatomyositis (DM) there is strong histopathological evidence of a microvascular pathogenesis, including endothelial microtubular inclusions. In nonspecific myositis, perimysial and perivascular infiltrates in the muscle biopsy similar to DM are found. Microtubular inclusions in endothelial

Tubuloreticular structures in different types of myositis: Implications for pathogenesis

NARCIS (Netherlands)

Bronner, I.M.; Hoogendijk, J.E.; Veldman, H.; Ramkema, M; Weerman, M.A.V.; Rozemuller, A.J.M.; Visser, M.

2008-01-01

In dermatomyositis (DM) there is strong histopathological evidence of a microvascular pathogenesis, including endothelial microtubular inclusions. In nonspecific myositis, perimysial and perivascular infiltrates in the muscle biopsy similar to DM are found. Microtubular inclusions in endothelial

Filovirus pathogenesis and immune evasion: insights from Ebola virus and Marburg virus

Energy Technology Data Exchange (ETDEWEB)

Messaoudi, Ilhem; Amarasinghe, Gaya K.; Basler, Christopher F.

2015-10-06

Ebola viruses and Marburg viruses, members of the filovirus family, are zoonotic pathogens that cause severe disease in people, as highlighted by the latest Ebola virus epidemic in West Africa. Filovirus disease is characterized by uncontrolled virus replication and the activation of host responses that contribute to pathogenesis. Underlying these phenomena is the potent suppression of host innate antiviral responses, particularly the type I interferon response, by viral proteins, which allows high levels of viral replication. In this Review, we describe the mechanisms used by filoviruses to block host innate immunity and discuss the links between immune evasion and filovirus pathogenesis.

Helicobacter pylori infection: An overview of bacterial virulence factors and pathogenesis

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Cheng-Yen Kao

2016-02-01

Full Text Available Helicobacter pylori pathogenesis and disease outcomes are mediated by a complex interplay between bacterial virulence factors, host, and environmental factors. After H. pylori enters the host stomach, four steps are critical for bacteria to establish successful colonization, persistent infection, and disease pathogenesis: (1 Survival in the acidic stomach; (2 movement toward epithelium cells by flagella-mediated motility; (3 attachment to host cells by adhesins/receptors interaction; (4 causing tissue damage by toxin release. Over the past 20 years, the understanding of H. pylori pathogenesis has been improved by studies focusing on the host and bacterial factors through epidemiology researches and molecular mechanism investigations. These include studies identifying the roles of novel virulence factors and their association with different disease outcomes, especially the bacterial adhesins, cag pathogenicity island, and vacuolating cytotoxin. Recently, the development of large-scale screening methods, including proteomic, and transcriptomic tools, has been used to determine the complex gene regulatory networks in H. pylori. In addition, a more available complete genomic database of H. pylori strains isolated from patients with different gastrointestinal diseases worldwide is helpful to characterize this bacterium. This review highlights the key findings of H. pylori virulence factors reported over the past 20 years.

Evolving Concepts in the Pathogenesis of NASH: Beyond Steatosis and Inflammation

Directory of Open Access Journals (Sweden)

William Peverill

2014-05-01

Full Text Available Non-alcoholic steatohepatitis (NASH is characterised by hepatic steatosis and inflammation and, in some patients, progressive fibrosis leading to cirrhosis. An understanding of the pathogenesis of NASH is still evolving but current evidence suggests multiple metabolic factors critically disrupt homeostasis and induce an inflammatory cascade and ensuing fibrosis. The mechanisms underlying these changes and the complex inter-cellular interactions that mediate fibrogenesis are yet to be fully elucidated. Lipotoxicity, in the setting of excess free fatty acids, obesity, and insulin resistance, appears to be the central driver of cellular injury via oxidative stress. Hepatocyte apoptosis and/or senescence contribute to activation of the inflammasome via a variety of intra- and inter-cellular signalling mechanisms leading to fibrosis. Current evidence suggests that periportal components, including the ductular reaction and expansion of the hepatic progenitor cell compartment, may be involved and that the Th17 response may mediate disease progression. This review aims to provide an overview of the pathogenesis of NASH and summarises the evidence pertaining to key mechanisms implicated in the transition from steatosis and inflammation to fibrosis. Currently there are limited treatments for NASH although an increasing understanding of its pathogenesis will likely improve the development and use of interventions in the future.

Roles of microRNA-34a in the pathogenesis of placenta accreta.

Science.gov (United States)

Umemura, Kota; Ishioka, Shin-Ichi; Endo, Toshiaki; Ezaka, Yoshiaki; Takahashi, Madoka; Saito, Tsuyoshi

2013-01-01

MicroRNA-34a (miR-34a) is associated with invasion and metastasis of various cancers. The trophoblastic cells of placenta accreta invade into the myometrium in a similar way to the invasion of cancers. We studied the roles of miR-34a in the pathogenesis of placenta accreta. The human choriocarcinoma cell line JAR was used for in vitro experiments as a model of trophoblasts, and placental tissues from the operative specimen of patients with or without placenta accreta were used for experiments in vivo. Morpholino antisense oligomer against miR-34a (miR-34a Morpho/AS) was added to JAR, and the expression of miR-34a and plasminogen activator inhibitor-1 (PAI-1) was determined by real time PCR. The effects of antisense, interleukin (IL)-6 and IL-8 in the process of invasion were studied with an invasion assay. Expression of miR-34a in vivo was studied with the use of fluorescent in situ hybridization (FISH). Expression of miR-34a was inhibited by 65% with the administration of antisense, and a slight increase in miR-34a expression was observed with the addition of IL-6 and IL-8. PAI-1 expression decreased with the addition of IL-6 and IL-8, and increased with the administration of antisense. There was an increase in invasive capacity through the inhibition of miR-34a expression. Strong FISH expression of miR-34a was observed in trophoblast cells of non-placenta accreta, and a clear decrease in miR-34a expression was observed in those of placenta accreta. Expression of miR-34a was downregulated in placenta accreta. In vitro experiments also showed that the invasive potential of JAR increased by suppressing miR-34a, probably through the expression of PAI-1. © 2012 The Authors. Journal of Obstetrics and Gynaecology Research © 2012 Japan Society of Obstetrics and Gynecology.

Central N-acetyl aspartylglutamate deficit: a possible pathogenesis of schizophrenia.

Science.gov (United States)

Tsai, Shih-Jen

2005-09-01

The "glutamate hypothesis" of schizophrenia has emerged from the finding that phencyclidine (PCP) induces psychotic-like behaviors in rodents, possibly by blocking the N-methyl-D-aspartate (NMDA) subtype of glutamate receptor, thereby causing increased glutamate release. N-acetyl aspartylglutamate (NAAG), an endogenous peptide abundant in mammalian nervous systems, is localized in certain brain cells, including cortical and hippocampal pyramidal neurons. NAAG is synthesized from N-acetylaspartate (NAA) and glutamate, and NAA availability may limit the rate of NAAG synthesis. Although NAAG is known to have some neurotransmitter-like functions, NAA does not. NAAG is a highly selective agonist of the type 3 metabotropic glutamate receptor (mGluR3, a presynaptic autoreceptor) and can inhibit glutamate release. In addition, at low levels, NAAG is an NMDA receptor antagonist, and blocking of NMDA receptors may increase glutamate release. Taken together, low central NAAG levels may antagonize the effect of glutamate at NMDA receptors and decrease its agonistic effect on presynaptic mGluR3; both activities could increase glutamate release, similar to the increase demonstrated in the PCP model of schizophrenia. In this report, it is suggested that the central NAAG deficit, possibly through decreased synthesis or increased degradation of NAAG, may play a role in the pathogenesis of schizophrenia. Evidence is presented and discussed from magnetic resonance, postmortem, animal model, schizophrenia treatment, and genetic studies. The central NAAG deficit model of schizophrenia could explain the disease process, from the perspectives of both neurodevelopment and neurodegeneration, and may point to potential treatments for schizophrenia.

[Pathomechanism of diabetic neuropathy: background of the pathogenesis-oriented therapy].

Science.gov (United States)

Winkler, Gábor; Kempler, Péter

2010-06-13

The pathomechanism of diabetic neuropathy remains still poorly understood, however, a broad spectrum of novel findings associated with therapeutic consequences emerged during the last decades. Both disturbed function of primary hemostasis and increased activity of coagulation system contribute to the reduced endoneurial blood flow. Increased superoxide anion production induced by hyperglycemia leads to decreased activity of glycerinaldehid-3-phosphate dehydrogenase and to consequential increased activity of alternative pathways, including the polyol-, hexosamine-, diacilglycerol protein kinase-C- and advanced glycation pathways. Advanced glycation endproducts increase the activity of the nuclear-factor kappa-B, as well as the production of vasoactive factors and cytokines (interleukin-1, -6, tumor necrosis factor alpha). The aim of pathogenetic oriented treatment is to slow down, stop or reverse the progression of neuropathy. Components of pathogenetic oriented treatment are glycaemic control, management of risk factors, benfotiamine and alpha-lipoic acid. On one hand, transketolase-activator benfotiamine inhibits alternative pathways induced by hyperglycemia (the polyol-, hexosamine-, diacilglycerol protein kinase-C-, and advanced glycation pathways), while, on the other hand, it increases the activity of the pentose-phosphate-shunt. The clinical effectiveness of benfotiamine has been shown in many international and Hungarian trials. Alpha-lipoic acid as a powerful antioxidant decreases oxidative stress and this way increases the activity of glycerinaldehid-3-phosphate dehydrogenase. Alpha-lipoic acid administered in infusion or oral treatment decreases both symptoms of neuropathy and neuropathic deficit. In conclusion, the case of diabetic neuropathy illustrates well, how widening of our knowledge on pathogenesis might contribute to successful therapy.

Enterobacterial involvement in the pathogenesis of secondary ankylosing spondylitis.

Science.gov (United States)

van Bohemen, C G; Weterings, E; Goei The, H S; Grumet, F C; Zanen, H C

1988-01-01

Ankylosing spondylitis (AS) is closely associated with the histocompatibility antigen HLA-B27. Pathogenesis of AS is thought to involve interactions between B27 and certain enterobacterial antigens. However, this is uncertain and contested by some. The present paper argues that the presence of statistically raised specific serum IgA to a common enterobacterial heat modifiable major outer membrane protein (h-momp; Mr 35,000) in active AS (N = 25; IgA = 1485 +/- 20) in comparison to controls, most notably hospital patients without known arthropathies or gastrointestinal disease (N = 12; IgA = 548 +/- 59), supports an inductive contribution of enterobacterial antigens to the pathogenesis of secondary AS. Serum IgG and IgM did not statistically differ. Raised specific serum IgA to h-momp might indicate enterobacterial antigenic stimulation from the gastrointestinal tract. It does not necessarily imply direct involvement in the pathogenesis of primary AS. H-momp appears to be a convenient tool for serological studies of AS and at present is likely to be more suitable than other bacterial antigens, notably those with B27-like epitopes. Namely, the confirmed presence in AS of enterobacteria with freely accessible B27-like antigenic epitopes on their cell surface might induce unusual tolerance to these organisms in B27 positive hosts, thus causing chronic inflammation, initially sacroiliitis (and spondylitis) due to the proximity of presacral and para-aortic colon draining lymph nodes, later becoming more generalized (for reasons unclear) to include other lesions (e.g. peripheral arthritis, uveitis, enthesopathies). Thus, antibodies to B27-like antigenic epitopes need not be detectable or may be absent. Also, cellular immune responsiveness to these antigens might be involved.

Intranuclear interactomic inhibition of NF-κB suppresses LPS-induced severe sepsis

International Nuclear Information System (INIS)

Park, Sung-Dong; Cheon, So Yeong; Park, Tae-Yoon; Shin, Bo-Young; Oh, Hyunju; Ghosh, Sankar; Koo, Bon-Nyeo; Lee, Sang-Kyou

2015-01-01

Suppression of nuclear factor-κB (NF-κB) activation, which is best known as a major regulator of innate and adaptive immune responses, is a potent strategy for the treatment of endotoxic sepsis. To inhibit NF-κB functions, we designed the intra-nuclear transducible form of transcription modulation domain (TMD) of RelA (p65), called nt-p65-TMD, which can be delivered effectively into the nucleus without influencing the cell viability, and work as interactomic inhibitors via disruption of the endogenous p65-mediated transcription complex. nt-p65-TMD effectively inhibited the secretion of pro-inflammatory cytokines, including TNF-α, IL-1β, or IL-6 from BV2 microglia cells stimulated by lipopolysaccharide (LPS). nt-p65-TMD did not inhibit tyrosine phosphorylation of signaling mediators such as ZAP-70, p38, JNK, or ERK involved in T cell activation, but was capable of suppressing the transcriptional activity of NF-κB without the functional effect on that of NFAT upon T-cell receptor (TCR) stimulation. The transduced nt-p65-TMD in T cell did not affect the expression of CD69, however significantly inhibited the secretion of T cell-specific cytokines such as IL-2, IFN-γ, IL-4, IL-17A, or IL-10. Systemic administration of nt-p65-TMD showed a significant therapeutic effect on LPS-induced sepsis model by inhibiting pro-inflammatory cytokines secretion. Therefore, nt-p65-TMD can be a novel therapeutics for the treatment of various inflammatory diseases, including sepsis, where a transcription factor has a key role in pathogenesis, and further allows us to discover new functions of p65 under normal physiological condition without genetic alteration. - Highlights: • The nt-p65-TMD is intra-nuclear interactomic inhibitor of endogenous p65. • The nt-p65-TMD effectively inhibited the secretion of pro-inflammatory cytokines. • The excellent therapeutic potential of nt-p65-TMD was confirmed in sepsis model

Intranuclear interactomic inhibition of NF-κB suppresses LPS-induced severe sepsis

Energy Technology Data Exchange (ETDEWEB)

Park, Sung-Dong [Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Cheon, So Yeong [Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Park, Tae-Yoon; Shin, Bo-Young [Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Oh, Hyunju; Ghosh, Sankar [Department of Microbiology and Immunology, College of Physicians and Surgeons, Columbia University, New York, NY 10032 (United States); Koo, Bon-Nyeo, E-mail: koobn@yuhs.ac [Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Lee, Sang-Kyou, E-mail: sjrlee@yonsei.ac.kr [Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of)

2015-08-28

Suppression of nuclear factor-κB (NF-κB) activation, which is best known as a major regulator of innate and adaptive immune responses, is a potent strategy for the treatment of endotoxic sepsis. To inhibit NF-κB functions, we designed the intra-nuclear transducible form of transcription modulation domain (TMD) of RelA (p65), called nt-p65-TMD, which can be delivered effectively into the nucleus without influencing the cell viability, and work as interactomic inhibitors via disruption of the endogenous p65-mediated transcription complex. nt-p65-TMD effectively inhibited the secretion of pro-inflammatory cytokines, including TNF-α, IL-1β, or IL-6 from BV2 microglia cells stimulated by lipopolysaccharide (LPS). nt-p65-TMD did not inhibit tyrosine phosphorylation of signaling mediators such as ZAP-70, p38, JNK, or ERK involved in T cell activation, but was capable of suppressing the transcriptional activity of NF-κB without the functional effect on that of NFAT upon T-cell receptor (TCR) stimulation. The transduced nt-p65-TMD in T cell did not affect the expression of CD69, however significantly inhibited the secretion of T cell-specific cytokines such as IL-2, IFN-γ, IL-4, IL-17A, or IL-10. Systemic administration of nt-p65-TMD showed a significant therapeutic effect on LPS-induced sepsis model by inhibiting pro-inflammatory cytokines secretion. Therefore, nt-p65-TMD can be a novel therapeutics for the treatment of various inflammatory diseases, including sepsis, where a transcription factor has a key role in pathogenesis, and further allows us to discover new functions of p65 under normal physiological condition without genetic alteration. - Highlights: • The nt-p65-TMD is intra-nuclear interactomic inhibitor of endogenous p65. • The nt-p65-TMD effectively inhibited the secretion of pro-inflammatory cytokines. • The excellent therapeutic potential of nt-p65-TMD was confirmed in sepsis model.

Tetrahydroxystilbene glucoside improves TNF-α-induced endothelial dysfunction: involvement of TGFβ/Smad pathway and inhibition of vimentin expression.

Science.gov (United States)

Yao, Wenjuan; Gu, Chengjing; Shao, Haoran; Meng, Guoliang; Wang, Huiming; Jing, Xiang; Zhang, Wei

2015-01-01

Endothelial dysfunction plays an important role in the pathogenesis of atherogenesis. 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside (TSG), an active component of the rhizome extract from Polygonum multiflorum (PM), exhibits significant anti-atherosclerotic activity. Here, we used human umbilical vein endothelial cells (HUVECs) induced by tumor necrosis factor-α (TNF-α) in vitro to investigate the cytoprotective effects of TSG on TNF-α-induced endothelial injury and the related mechanisms. Pretreatment with 50 and 100 μM TSG markedly attenuated TNF-α-induced loss of cell viability and release of lactate dehydrogenase (LDH) and inhibited TNF-α-induced cell apoptosis. The inhibition of vimentin expression was involved in the cytoprotection afforded by TSG. Using inhibitors for PI3K and TGFβ or siRNA for Akt and Smad2, we found that vimentin production in HUVECs is regulated by TGFβ/Smad signaling, but not by PI3K-Akt-mTOR signaling. Meanwhile, TSG inhibited both the expression of TGFβ1 and the phosphorylation of Smad2 and Smad3, and TSG suppressed the nuclear translocation of Smad4 induced by TNF-α. These results suggest that TSG protects HUVECs against TNF-α-induced cell damage by inhibiting vimentin expression via the interruption of the TGFβ/Smad signaling pathway.

Edaravone protected PC12 cells against MPP(+)-cytoxicity via inhibiting oxidative stress and up-regulating heme oxygenase-1 expression.

Science.gov (United States)

Cheng, Baohua; Guo, Yunliang; Li, Chuangang; Ji, Bingyuan; Pan, Yanyou; Chen, Jing; Bai, Bo

2014-08-15

Oxidative stress is involved in the pathogenesis of Parkinson's disease (PD). Edaravone has been shown to have a neuroprotective effect. In the present work, we investigated the effect of edaravone on 1-methyl-4-phenylpyridinium (MPP(+))-treated PC12 cells. Edaravone inhibited the decrease of cell viability and apoptosis induced by MPP(+) in PC12 cells. In addition, edaravone alleviated intracellular reactive oxygen species (ROS) production. MPP(+) induced heme oxygenase-1 (HO-1) expression, which was further enhanced by edaravone. The inhibitor of HO-1 zinc protoporphyrin-IX attenuated the neuroprotection of edaravone. So edaravone protected PC12 cells against MPP(+)-cytoxicity via inhibiting oxidative stress and up-regulating HO-1 expression. The data showed that edaravone was neuroprotective and could be potentially therapeutics for PD in future. Copyright © 2014 Elsevier B.V. All rights reserved.

Host Lipid Mediators in Leprosy: The Hypothesized Contributions to Pathogenesis

Directory of Open Access Journals (Sweden)

Carlos A. M. Silva

2018-02-01

Full Text Available The spectrum of clinical forms observed in leprosy and its pathogenesis are dictated by the host’s immune response against Mycobacterium leprae, the etiological agent of leprosy. Previous results, based on metabolomics studies, demonstrated a strong relationship between clinical manifestations of leprosy and alterations in the metabolism of ω3 and ω6 polyunsaturated fatty acids (PUFAs, and the diverse set of lipid mediators derived from PUFAs. PUFA-derived lipid mediators provide multiple functions during acute inflammation, and some lipid mediators are able to induce both pro- and anti-inflammatory responses as determined by the cell surface receptors being expressed, as well as the cell type expressing the receptors. However, little is known about how these compounds influence cellular immune activities during chronic granulomatous infectious diseases, such as leprosy. Current evidence suggests that specialized pro-resolving lipid mediators (SPMs are involved in the down-modulation of the innate and adaptive immune response against M. leprae and that alteration in the homeostasis of pro-inflammatory lipid mediators versus SPMs is associated with dramatic shifts in the pathogenesis of leprosy. In this review, we discuss the possible consequences and present new hypotheses for the involvement of ω3 and ω6 PUFA metabolism in the pathogenesis of leprosy. A specific emphasis is placed on developing models of lipid mediator interactions with the innate and adaptive immune responses and the influence of these interactions on the outcome of leprosy.

Current insights in sepsis: from pathogenesis to new treatment targets

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Wiersinga, W. Joost

2011-01-01

Sepsis continues to be a leading cause of ICU death. This review summarizes current knowledge on sepsis pathogenesis and new therapeutical strategies. Although systemic inflammatory response syndrome predominates in early sepsis, the compensatory anti-inflammatory response syndrome causes

Urinary Tract Infection: Pathogenesis and Outlook.

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McLellan, Lisa K; Hunstad, David A

2016-11-01

The clinical syndromes comprising urinary tract infection (UTI) continue to exert significant impact on millions of patients worldwide, most of whom are otherwise healthy women. Antibiotic therapy for acute cystitis does not prevent recurrences, which plague up to one fourth of women after an initial UTI. Rising antimicrobial resistance among uropathogenic bacteria further complicates therapeutic decisions, necessitating new approaches based on fundamental biological investigation. In this review, we highlight contemporary advances in the field of UTI pathogenesis and how these might inform both our clinical perspective and future scientific priorities. Copyright © 2016 Elsevier Ltd. All rights reserved.

High Glucose Promotes Aβ Production by Inhibiting APP Degradation

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Zhang, Shuting; Song, Weihong

2013-01-01

Abnormal deposition of neuriticplaques is the uniqueneuropathological hallmark of Alzheimer’s disease (AD).Amyloid β protein (Aβ), the major component of plaques, is generated from sequential cleavage of amyloidβ precursor protein (APP) by β-secretase and γ-secretase complex. Patients with diabetes mellitus (DM), characterized by chronic hyperglycemia,have increased risk of AD development.However, the role of high blood glucose in APP processing and Aβ generation remains elusive. In this study, we investigated the effect of high glucose on APP metabolism and Aβ generation in cultured human cells. We found that high glucose treatment significantly increased APP protein level in both neuronal-like and non-neuronal cells, and promoted Aβ generation. Furthermore, we found that high glucose-induced increase of APP level was not due to enhancement of APP gene transcription but resulted from inhibition of APP protein degradation. Taken together, our data indicated that hyperglycemia could promote AD pathogenesis by inhibiting APP degradation and enhancing Aβ production. More importantly, the elevation of APP level and Aβ generation by high glucose was caused by reduction of APP turnover rate.Thus,our study provides a molecular mechanism of increased risk of developing AD in patients withDMand suggests thatglycemic control might be potentially beneficial for reducing the incidence of AD in diabetic patients and delaying the AD progression. PMID:23894546

Comparative Pathogenesis and Systems Biology for Biodefense Virus Vaccine Development

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Gavin C. Bowick

2010-01-01

Full Text Available Developing vaccines to biothreat agents presents a number of challenges for discovery, preclinical development, and licensure. The need for high containment to work with live agents limits the amount and types of research that can be done using complete pathogens, and small markets reduce potential returns for industry. However, a number of tools, from comparative pathogenesis of viral strains at the molecular level to novel computational approaches, are being used to understand the basis of viral attenuation and characterize protective immune responses. As the amount of basic molecular knowledge grows, we will be able to take advantage of these tools not only to rationally attenuate virus strains for candidate vaccines, but also to assess immunogenicity and safety in silico. This review discusses how a basic understanding of pathogenesis, allied with systems biology and machine learning methods, can impact biodefense vaccinology.

Ellagic acid promotes A{beta}42 fibrillization and inhibits A{beta}42-induced neurotoxicity

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Feng, Ying [Department of Histology and Embryology, College of Basic Medical Science, China Medical University, Shenyang 110001 (China); Tsinghua University School of Medicine, Haidian District, Beijing 100084 (China); Yang, Shi-gao; Du, Xue-ting; Zhang, Xi; Sun, Xiao-xia; Zhao, Min [Tsinghua University School of Medicine, Haidian District, Beijing 100084 (China); Sun, Gui-yuan, E-mail: sungy2004@sohu.com [Department of Histology and Embryology, College of Basic Medical Science, China Medical University, Shenyang 110001 (China); Liu, Rui-tian, E-mail: rtliu@tsinghua.edu.cn [Tsinghua University School of Medicine, Haidian District, Beijing 100084 (China)

2009-12-25

Smaller, soluble oligomers of {beta}-amyloid (A{beta}) play a critical role in the pathogenesis of Alzheimer's disease (AD). Selective inhibition of A{beta} oligomer formation provides an optimum target for AD therapy. Some polyphenols have potent anti-amyloidogenic activities and protect against A{beta} neurotoxicity. Here, we tested the effects of ellagic acid (EA), a polyphenolic compound, on A{beta}42 aggregation and neurotoxicity in vitro. EA promoted A{beta} fibril formation and significant oligomer loss, contrary to previous results that polyphenols inhibited A{beta} aggregation. The results of transmission electron microscopy (TEM) and Western blot displayed more fibrils in A{beta}42 samples co-incubated with EA in earlier phases of aggregation. Consistent with the hypothesis that plaque formation may represent a protective mechanism in which the body sequesters toxic A{beta} aggregates to render them harmless, our MTT results showed that EA could significantly reduce A{beta}42-induced neurotoxicity toward SH-SY5Y cells. Taken together, our results suggest that EA, an active ingredient in many fruits and nuts, may have therapeutic potential in AD.

Gene knockout of tau expression does not contribute to the pathogenesis of prion disease.

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Lawson, Victoria A; Klemm, Helen M; Welton, Jeremy M; Masters, Colin L; Crouch, Peter; Cappai, Roberto; Ciccotosto, Giuseppe D

2011-11-01

Prion diseases or transmissible spongiform encephalopathies are a group of fatal and transmissible disorders affecting the central nervous system of humans and animals. The principal agent of prion disease transmission and pathogenesis is proposed to be an abnormal protease-resistant isoform of the normal cellular prion protein. The microtubule-associated protein tau is elevated in patients with Creutzfeldt-Jakob disease. To determine whether tau expression contributes to prion disease pathogenesis, tau knockout and control wild-type mice were infected with the M1000 strain of mouse-adapted human prions. Immunohistochemical analysis for total tau expression in prion-infected wild-type mice indicated tau aggregation in the cytoplasm of a subpopulation of neurons in regions associated with spongiform change. Western immunoblot analysis of brain homogenates revealed a decrease in total tau immunoreactivity and epitope-specific changes in tau phosphorylation. No significant difference in incubation period or other disease features were observed between tau knockout and wild-type mice with clinical prion disease. These results demonstrate that, in this model of prion disease, tau does not contribute to the pathogenesis of prion disease and that changes in the tau protein profile observed in mice with clinical prion disease occurs as a consequence of the prion-induced pathogenesis.

Pathogenesis of Idiopathic Pulmonary Fibrosis

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Wolters, Paul J.; Collard, Harold R.; Jones, Kirk D.

2014-01-01

Idiopathic pulmonary fibrosis (IPF) is a fibrosing interstitial lung disease associated with aging that is characterized by the histopathological pattern of usual interstitial pneumonia. Although an understanding of the pathogenesis of IPF is incomplete, recent advances delineating specific clinical and pathologic features of IPF have led to better definition of the molecular pathways that are pathologically activated in the disease. In this review we highlight several of these advances, with a focus on genetic predisposition to IPF and how genetic changes, which occur primarily in epithelial cells, lead to activation of profibrotic pathways in epithelial cells. We then discuss the pathologic changes within IPF fibroblasts and the extracellular matrix, and we conclude with a summary of how these profibrotic pathways may be interrelated. PMID:24050627

Unraveling the Pathogenesis of MDS: The NLRP3 Inflammasome and Pyroptosis Drive the MDS Phenotype.

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Sallman, David A; Cluzeau, Thomas; Basiorka, Ashley A; List, Alan

2016-01-01

Myelodysplastic syndromes (MDS) are characterized by bone marrow cytological dysplasia and ineffective hematopoiesis in the setting of recurrent somatic gene mutations and chromosomal abnormalities. The underlying pathogenic mechanisms that drive a common clinical phenotype from a diverse array of genetic abnormalities have only recently begun to emerge. Accumulating evidence has highlighted the integral role of the innate immune system in upregulating inflammatory cytokines via NF-κB activation in the pathogenesis of MDS. Recent investigations implicate activation of the NLRP3 inflammasome in hematopoietic stem/progenitor cells as a critical convergence signal in MDS with consequent clonal expansion and pyroptotic cell death though caspase-1 maturation. Specifically, the alarmin S100A9 and/or founder gene mutations trigger pyroptosis through the generation of reactive oxygen species leading to assembly and activation of the redox-sensitive NLRP3 inflammasome and β-catenin, assuring propagation of the MDS clone. More importantly, targeted inhibition of varied steps in this pathway restore effective hematopoiesis. Together, delineation of the role of pyroptosis in the clinical phenotype of MDS patients has identified novel therapeutic strategies that offer significant promise in the treatment of MDS.

The involvement of T lymphocytes in the pathogenesis of endometriotic tissues overgrowth in women with endometriosis

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Krzysztof Szyllo

2003-01-01

Full Text Available Background: Endometriosis, uncontrolled proliferation of ectopic and eutopic endometriotic tissues, is common in women at reproductive age, and may affect fertility. The role of macrophages in the pathogenesis is well proved, but engagement of T cells in the pathogenesis of endometriosis is a matter of controversy

Biofilm inhibition activity of compounds isolated from two Eunicea species collected at the Caribbean Sea

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Yenny Martínez Díaz

Full Text Available Abstract Biofilm has a primary role in the pathogenesis of diseases and in the attachment of multicellular organisms to a fouled surface. Because of that, the control of bacterial biofilms has been identified as an important target. In the present study, five lipid compounds isolated from soft coral Eunicea sp. and three terpenoids together with a mixture of sterols from Eunicea fusca collected at the Colombian Caribbean Sea showed different effectiveness against biofilm formation by three marine bacteria associated with immersed fouled surfaces, Ochrobactrum pseudogringnonense,Alteromona macleodii and Vibrio harveyi, and against two known biofilm forming bacteria, Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 25923. The pure compounds were characterized by NMR, HRESI-MS, HRGC-MS and optical rotation. The most effective compounds were batyl alcohol (1 and fuscoside E peracetate (6, acting against four strains without affecting their microbial growth. Compound 1 showed biofilm inhibition greater than 30% against A. macleodii, and up to 60% against O. pseudogringnonense,V. harveyi and S. aureus. Compound 6 inhibited O. pseudogringnonense and V. harveyi between 25 and 50%, and P. aeruginosa or S. aureus up to 60% at 0.5 mg/ml. The results suggest that these compounds exhibit specific biofilm inhibition with lower antimicrobial effect against the bacterial species assayed.

Airborne geoid mapping of land and sea areas of East Malaysia

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Jamil, H.; Kadir, M.; Forsberg, R.; Olesen, A.; Isa, M. N.; Rasidi, S.; Mohamed, A.; Chihat, Z.; Nielsen, E.; Majid, F.; Talib, K.; Aman, S.

2017-02-01

This paper describes the development of a new geoid-based vertical datum from airborne gravity data, by the Department of Survey and Mapping Malaysia, on land and in the South China Sea out of the coast of East Malaysia region, covering an area of about 610,000 square kilometres. More than 107,000 km flight line of airborne gravity data over land and marine areas of East Malaysia has been combined to provide a seamless land-to-sea gravity field coverage; with an estimated accuracy of better than 2.0 mGal. The iMAR-IMU processed gravity anomaly data has been used during a 2014-2016 airborne survey to extend a composite gravity solution across a number of minor gaps on selected lines, using a draping technique. The geoid computations were all done with the GRAVSOFT suite of programs from DTU-Space. EGM2008 augmented with GOCE spherical harmonic model has been used to spherical harmonic degree N = 720. The gravimetric geoid first was tied at one tide-gauge (in Kota Kinabalu, KK2019) to produce a fitted geoid, my_geoid2017_fit_kk. The fitted geoid was offset from the gravimetric geoid by +0.852 m, based on the comparison at the tide-gauge benchmark KK2019. Consequently, orthometric height at the six other tide gauge stations was computed from HGPS Lev = hGPS - Nmy_geoid2017_.t_kk. Comparison of the conventional (HLev) and GPS-levelling heights (HGPS Lev) at the six tide gauge locations indicate RMS height difference of 2.6 cm. The final gravimetric geoidwas fitted to the seven tide gauge stations and is known as my_geoid2017_fit_east. The accuracy of the gravimetric geoid is estimated to be better than 5 cm across most of East Malaysia land and marine areas

Psilocybin-Induced Deficits in Automatic and Controlled Inhibition are Attenuated by Ketanserin in Healthy Human Volunteers

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Quednow, Boris B; Kometer, Michael; Geyer, Mark A; Vollenweider, Franz X

2012-01-01

The serotonin-2A receptor (5-HT2AR) has been implicated in the pathogenesis of schizophrenia and related inhibitory gating and behavioral inhibition deficits of schizophrenia patients. The hallucinogen psilocybin disrupts automatic forms of sensorimotor gating and response inhibition in humans, but it is unclear so far whether the 5-HT2AR or 5-HT1AR agonist properties of its bioactive metabolite psilocin account for these effects. Thus, we investigated whether psilocybin-induced deficits in automatic and controlled inhibition in healthy humans could be attenuated by the 5-HT2A/2CR antagonist ketanserin. A total of 16 healthy participants received placebo, ketanserin (40 mg p.o.), psilocybin (260 μg/kg p.o.), or psilocybin plus ketanserin in a double-blind, randomized, and counterbalanced order. Sensorimotor gating was measured by prepulse inhibition (PPI) of the acoustic startle response. The effects on psychopathological core dimensions and behavioral inhibition were assessed by the altered states of consciousness questionnaire (5D-ASC), and the Color-Word Stroop Test. Psilocybin decreased PPI at short lead intervals (30 ms), increased all 5D-ASC scores, and selectively increased errors in the interference condition of the Stroop Test. Stroop interference and Stroop effect of the response latencies were increased under psilocybin as well. Psilocybin-induced alterations were attenuated by ketanserin pretreatment, whereas ketanserin alone had no significant effects. These findings suggest that the disrupting effects of psilocybin on automatic and controlled inhibition processes are attributable to 5-HT2AR stimulation. Sensorimotor gating and attentional control deficits of schizophrenia patients might be due to changes within the 5-HT2AR system. PMID:21956447

MERS-CoV Accessory ORFs Play Key Role for Infection and Pathogenesis

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Menachery, Vineet D.; Mitchell, Hugh D.; Cockrell, Adam S.; Gralinski, Lisa E.; Yount, Boyd L.; Graham, Rachel L.; McAnarney, Eileen T.; Douglas, Madeline G.; Scobey, Trevor; Beall, Anne; Dinnon, Kenneth; Kocher, Jacob F.; Hale, Andrew E.; Stratton, Kelly G.; Waters, Katrina M.; Baric, Ralph S.; Racaniello, Vincent R.

2017-08-22

While dispensable for viral replication, coronavirus (CoV) accessory open reading frame (ORF) proteins often play critical roles during infection and pathogenesis. Utilizing a previously generated mutant, we demonstrate that the absence of all four Middle East respiratory syndrome CoV (MERS-CoV) accessory ORFs (deletion of ORF3, -4a, -4b, and -5 [dORF3-5]) has major implications for viral replication and pathogenesis. Importantly, attenuation of the dORF3-5 mutant is primarily driven by dysregulated host responses, including disrupted cell processes, augmented interferon (IFN) pathway activation, and robust inflammation.In vitroreplication attenuation also extends toin vivomodels, allowing use of dORF3-5 as a live attenuated vaccine platform. Finally, examination of ORF5 implicates a partial role in modulation of NF-κB-mediated inflammation. Together, the results demonstrate the importance of MERS-CoV accessory ORFs for pathogenesis and highlight them as potential targets for surveillance and therapeutic treatments moving forward.

IMPORTANCEThe initial emergence and periodic outbreaks of MERS-CoV highlight a continuing threat posed by zoonotic pathogens to global public health. In these studies, mutant virus generation demonstrates the necessity of accessory ORFs in regard to MERS-CoV infection and pathogenesis. With this in mind, accessory ORF functions can be targeted for both therapeutic and vaccine treatments in response to MERS-CoV and related group 2C coronaviruses. In addition, disruption of accessory ORFs in parallel may offer a rapid response platform to attenuation of future emergent strains based on both SARS- and MERS-CoV accessory ORF mutants.

Online testable concept maps: benefits for learning about the pathogenesis of disease.

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Ho, Veronica; Kumar, Rakesh K; Velan, Gary

2014-07-01

Concept maps have been used to promote meaningful learning and critical thinking. Although these are crucially important in all disciplines, evidence for the benefits of concept mapping for learning in medicine is limited. We performed a randomised crossover study to assess the benefits of online testable concept maps for learning in pathology by volunteer junior medical students. Participants (n = 65) were randomly allocated to either of two groups with equivalent mean prior academic performance, in which they were given access to either online maps or existing online resources for a 2-week block on renal disease. Groups then crossed over for a 2-week block on hepatic disease. Outcomes were assessed using timed online quizzes, which included questions unrelated to topics in the pathogenesis maps as an internal control. Questionnaires were administered to evaluate students' acceptance of the maps. In both blocks, the group with access to pathogenesis maps achieved significantly higher average scores than the control group on quiz questions related to topics covered by the maps (Block 1: p online testable pathogenesis maps are well accepted and can improve learning of concepts in pathology by medical students. © 2014 John Wiley & Sons Ltd.

High-throughput screening for novel anti-infectives using a C. elegans pathogenesis model.

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Conery, Annie L; Larkins-Ford, Jonah; Ausubel, Frederick M; Kirienko, Natalia V

2014-03-14

In recent history, the nematode Caenorhabditis elegans has provided a compelling platform for the discovery of novel antimicrobial drugs. In this protocol, we present an automated, high-throughput C. elegans pathogenesis assay, which can be used to screen for anti-infective compounds that prevent nematodes from dying due to Pseudomonas aeruginosa. New antibiotics identified from such screens would be promising candidates for treatment of human infections, and also can be used as probe compounds to identify novel targets in microbial pathogenesis or host immunity. Copyright © 2014 John Wiley & Sons, Inc.

CC-Chemokine CCL15 Expression and Possible Implications for the Pathogenesis of IgE-Related Severe Asthma

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Yasuo Shimizu

2012-01-01

Full Text Available Airway inflammation is accompanied by infiltration of inflammatory cells and an abnormal response of airway smooth muscle. These cells secrete chemokines and express the cell surface chemokine receptors that play an important role in the migration and degranulation of inflammatory cells. Omalizumab is a monoclonal antibody directed against immunoglobulin E, and its blocking of IgE signaling not only reduces inflammatory cell infiltration mediated by the Th2 immune response but also inhibits other immune responses. The chemokine CCL15 is influenced by omalizumab, and the source of CCL15 has been reported to be airway smooth muscle cells and basophils. CCL15 binds to its receptor CCR1, which has been reported to be expressed by various inflammatory cells and also by airway smooth muscle cells. Therefore, CCL15/CCR1 signaling could be a target for the treatment of asthma. We review the role of CCL15 in the pathogenesis of asthma and also discuss the influence of IgE-mediated immunomodulation via CCL15 and its receptor CCR1.

The Involvement of Mutual Inhibition of ERK and mTOR in PLCγ1-Mediated MMP-13 Expression in Human Osteoarthritis Chondrocytes

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Zejun Liu

2015-08-01

Full Text Available The issue of whether ERK activation determines matrix synthesis or degradation in osteoarthritis (OA pathogenesis currently remains controversial. Our previous study shows that PLCγ1 and mTOR are involved in the matrix metabolism of OA cartilage. Investigating the interplays of PLCγ1, mTOR and ERK in matrix degradation of OA will facilitate future attempts to manipulate ERK in OA prevention and therapy. Here, cultured human normal chondrocytes and OA chondrocytes were treated with different inhibitors or transfected with expression vectors, respectively. The levels of ERK, p-ERK, PLCγ1, p-PLCγ1, mTOR, p-mTOR and MMP-13 were then evaluated by Western blotting analysis. The results manifested that the expression level of ERK in human OA chondrocytes was lower than that in human normal articular chondrocytes, and the up-regulation of ERK could promote matrix synthesis, including the decrease in MMP-13 level and the increase in Aggrecan level in human OA chondrocytes. Furthermore, the PLCγ1/ERK axis and a mutual inhibition of mTOR and ERK were observed in human OA chondrocytes. Interestingly, activated ERK had no inhibitory effect on MMP-13 expression in PLCγ1-transformed OA chondrocytes. Combined with our previous study, the non-effective state of ERK activation by PLCγ1 on MMP-13 may be partly attributed to the inhibition of the PLCγ1/mTOR axis on the PLCγ1/ERK axis. Therefore, the study indicates that the mutual inhibition of ERK and mTOR is involved in PLCγ1-mediated MMP-13 expression in human OA chondrocytes, with important implication for the understanding of OA pathogenesis as well as for its prevention and therapy.

PATHOGENESIS OF OSTEOARTHRITIS AND SUBSTANTIATION OF THE USE OF STRONTIUM RANELATE

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Elena Mikhailovna Zaitseva

2013-01-01

Full Text Available Osteoarthritis (OA is one of the most common diseases, pain and joint dysfunction being its main symptoms. Although OA is a progressive disease causing disability, rapid progression is observed only in some patients. According to the data obtained by different authors, the progressive course of gonarthrosis is typical of 34–55% patients, which is likely to be attributed to variability of the risk factors of disease progression that every single patient has. As the reasons behind OA progression have been studied more thoroughly, the notion of the disease pathogenesis has recently changed. While articular cartilage lesion was considered to be the main reason and the joint space narrowing and concomitant changes in the subchondral bone (SCB were regarded as a secondary process SCB is now believed to play the initiating role in disease evolution. It was found that acceleration of metabolic processes in SCB in OA patients causes incomplete mineralization of bone and reduces its biomechanical properties. These data initiated the search for new approaches to therapy for OA. A large number of medications that are potentially able to inhibit disease progression are being actively studied. Special attention is paid to the agents affecting the processes of bone tissue remodeling. In addition to bisphosphonates and calcitonin (whose effectiveness in treating OA has been studied over the past decades, much attention has recently been paid to strontium derivatives, in particular, to strontium ranelate (SR. It has been proved that SR stimulates preosteoblast replication, osteoblast differentiation, type 1 collagen synthesis, and mineralization of bone matrix. Meanwhile, SR inhibits osteoclast differentiation and activity, resulting in the reduction of SCB resorption, which is a potentially significant effect in OA therapy. In addition to its effect on SCB, SR can influence the bone tissue. It wasfound during the studies that SR reliably enhances

Cutting edge: Antimalarial drugs inhibit IFN-β production through blockade of cyclic GMP-AMP synthase-DNA interaction.

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An, Jie; Woodward, Joshua J; Sasaki, Tomikazu; Minie, Mark; Elkon, Keith B

2015-05-01

Type I IFN is strongly implicated in the pathogenesis of systemic autoimmune diseases, such as lupus, and rare monogenic IFNopathies, including Aicardi-Goutières syndrome. Recently, a new DNA-activated pathway involving the enzyme cyclic GMP-AMP synthase (cGAS) was described and potentially linked to Aicardi-Goutières syndrome. To identify drugs that could potentially inhibit cGAS activity, we performed in silico screening of drug libraries. By computational analysis, we identified several antimalarial drugs (AMDs) that were predicted to interact with the cGAS/dsDNA complex. Our studies validated that several AMDs were effective inhibitors of IFN-β production and that they functioned by inhibiting dsDNA stimulation of cGAS. Because AMDs have been widely used in human diseases and have an excellent safety profile, our findings suggest new therapeutic strategies for the treatment of severe debilitating diseases associated with type I IFNs due to cGAS activation. Copyright © 2015 by The American Association of Immunologists, Inc.

Curcumin serves as a human kv1.3 blocker to inhibit effector memory T lymphocyte activities.

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Lian, Yi-Tian; Yang, Xiao-Fang; Wang, Zhao-Hui; Yang, Yong; Yang, Ying; Shu, Yan-Wen; Cheng, Long-Xian; Liu, Kun

2013-09-01

Curcumin, the principal active component of turmeric, has long been used to treat various diseases in India and China. Recent studies show that curcumin can serve as a therapeutic agent for autoimmune diseases via a variety of mechanisms. Effector memory T cells (T(EM), CCR7⁻ CD45RO⁺ T lymphocyte) have been demonstrated to play a crucial role in the pathogenesis of T cell-mediated autoimmune diseases, such as multiple sclerosis (MS) or rheumatoid arthritis (RA). Kv1.3 channels are predominantly expressed in T(EM) cells and control T(EM) activities. In the present study, we examined the effect of curcumin on human Kv1.3 (hKv1.3) channels stably expressed in HEK-293 cells and its ability to inhibit proliferation and cytokine secretion of T(EM) cells isolated from patients with MS or RA. Curcumin exhibited a direct blockage of hKv1.3 channels in a time-dependent and concentration-dependent manner. Moreover, the activation curve was shifted to a more positive potential, which was consistent with an open-channel blockade. Paralleling hKv1.3 inhibition, curcumin significantly inhibited proliferation and interferon-γ secretion of T(EM) cells. Our findings demonstrate that curcumin is able to inhibit proliferation and proinflammatory cytokine secretion of T(EM) cells probably through inhibition of hKv1.3 channels, which contributes to the potency of curcumin for the treatment of autoimmune diseases. This is probably one of pharmacological mechanisms of curcumin used to treat autoimmune diseases. Copyright © 2012 John Wiley & Sons, Ltd.

Propionibacterium acnes in the pathogenesis and immunotherapy of acne vulgaris.

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Liu, Pei-Feng; Hsieh, Yao-Dung; Lin, Ya-Ching; Two, Aimee; Shu, Chih-Wen; Huang, Chun-Ming

2015-01-01

Acne vulgaris, a multi-factorial disease, is one of the most common skin diseases, affecting an estimated 80% of Americans at some point during their lives. The gram-positive and anaerobic Propionibacterium acnes (P. acnes) bacterium has been implicated in acne inflammation and pathogenesis. Therapies for acne vulgaris using antibiotics generally lack bacterial specificity, promote the generation of antibiotic-resistant bacterial strains, and cause adverse effects. Immunotherapy against P. acnes or its antigens (sialidase and CAMP factor) has been demonstrated to be effective in mice, attenuating P. acnes-induced inflammation; thus, this method may be applied to develop a potential vaccine targeting P. acnes for acne vulgaris treatment. This review summarizes reports describing the role of P. acnes in the pathogenesis of acne and various immunotherapy-based approaches targeting P. acnes, suggesting the potential effectiveness of immunotherapy for acne vulgaris as well as P. acnes-associated diseases.

Oral submucous fibrosis: An update on current theories of pathogenesis.

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Arakeri, Gururaj; Rai, Kirthi Kumar; Hunasgi, Santosh; Merkx, M A W; Gao, Shan; Brennan, Peter A

2017-07-01

Over the last 40 years, many theories linking oral submucous fibrosis (OSMF) to various risk factors have been proposed. Spicy, pungent foods and irritants such as supari (areca nut), paan (betel leaves), tobacco (through chewing or smoking)-the common Asian habits of chewing the aforementioned agents-have all been incriminated as causative agents. Systemic factors such as nutritional deficiency, genetic predisposition and autoimmunity have also been proposed in the pathogenesis of OSMF. However, the precise aetiology of OSMF is still unknown, and no conclusive evidence has been found despite many extensive investigations on implicated factors. Most of the ideas proposed have been derived from the existing clinical and epidemiological data. We present a comprehensive review of the various theories regarding the pathogenesis of the condition, but have not concentrated on malignant transformation in this article. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Neutralizing Antibodies and Pathogenesis of Hepatitis C Virus Infection

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Françoise Stoll-Keller

2012-10-01

Full Text Available Hepatitis C virus (HCV infection is a major cause of chronic liver disease worldwide. The interplay between the virus and host innate and adaptive immune responses determines the outcome of infection. There is increasing evidence that host neutralizing responses play a relevant role in the resulting pathogenesis. Furthermore, viral evasion from host neutralizing antibodies has been revealed to be an important contributor in leading both to viral persistence in acute liver graft infection following liver transplantation, and to chronic viral infection. The development of novel model systems to study HCV entry and neutralization has allowed a detailed understanding of the molecular mechanisms of virus-host interactions during antibody-mediated neutralization. The understanding of these mechanisms will ultimately contribute to the development of novel antiviral preventive strategies for liver graft infection and an urgently needed vaccine. This review summarizes recent concepts of the role of neutralizing antibodies in viral clearance and protection, and highlights consequences of viral escape from neutralizing antibodies in the pathogenesis of HCV infection.

Invasive mold infections : virulence and pathogenesis of mucorales

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Morace, G.; Borghi, E.

2012-01-01

Mucorales have been increasingly reported as cause of invasive fungal infections in immunocompromised subjects, particularly in patients with haematological malignancies or uncontrolled diabetes mellitus and in those under deferoxamine treatment or undergoing dialysis. The disease often leads to a fatal outcome, but the pathogenesis of the infection is still poorly understood as well as the role of specific virulence determinants and the interaction with the host immune system. Members of the...

Pathogenesis and treatment of diabetic glomerulopathy

International Nuclear Information System (INIS)

Marre, M.; Le Jeune, J.J.

1995-01-01

Diabetic glomerulopathy is the consequence, at the glomerular level, of diabetes. Diagnosis is based on the association of proteinuria, arterial hypertension and an early reduction of glomerular filtration in a diabetic patient, generally insulin-dependent. Diabetic glomerulopathy is a complication of type I diabetes, which begins in childhood or adolescence, but can also be discovered in type II diabetes. A definite diagnosis requires histological evidences ; glomerular clearance measurements ( 125 I-iodothalamate or 51 Cr-EDTA) yield important information concerning glomerular filtration. The authors subsequently address pathogenesis and therapeutic regimens, and they report on the particularities of this condition in type II diabetes. (authors). 30 refs., 2 tabs

The pathogenesis of Ebola hemorrhagic fever.

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Takada, A; Kawaoka, Y

2001-10-01

Ebola virus causes lethal hemorrhagic disease in humans, yet there are still no satisfactory biological explanations to account for its extreme virulence. This review focuses on recent findings relevant to understanding the pathogenesis of Ebola virus infection and developing vaccines and effective therapy. The available data suggest that the envelope glycoprotein and the interaction of some viral proteins with the immune system are likely to play important roles in the extraordinary pathogenicity of this virus. There are also indications that genetically engineered vaccines, including plasmid DNA and viral vectors expressing Ebola virus proteins, and passive transfer of neutralizing antibodies could be feasible options for the control of Ebola virus-associated disease.

Why do motor neurons degenerate? Actualization in the pathogenesis of amyotrophic lateral sclerosis.

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Riancho, J; Gonzalo, I; Ruiz-Soto, M; Berciano, J

2016-02-04

Amyotrophic lateral sclerosis (ALS) is the most common neurodegenerative disease affecting motor neurons. Although a small proportion of ALS cases are familial in origin and linked to mutations in specific genes, most cases are sporadic and have a multifactorial aetiology. Some recent studies have increased our knowledge of ALS pathogenesis and raised the question of whether this disorder is a proteinopathy, a ribonucleopathy, an axonopathy, or a disease related to the neuronal microenvironment. This article presents a review of ALS pathogenesis. To this end, we have reviewed published articles describing either ALS patients or ALS animal models and we discuss how the main cellular pathways (gene processing, protein metabolism, oxidative stress, axonal transport, relationship with neuronal microenvironment) may be involved in motor neurons degeneration. ALS pathogenesis has not been fully elucidated. Recent studies suggest that although initial triggers may differ among patients, the final motor neurons degeneration mechanisms are similar in most patients once the disease is fully established. Copyright © 2016 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.

Leprosy and the eye a review of epidemiology, pathogenesis, ocular ...

African Journals Online (AJOL)

Objectives: 1. To update knowledge on the current trends in the epidemiology, pathogenesis, and treatment of leprosy 2. To highlight the ocular complications associated with leprosy. Methodology:Current literature on various aspects of leprosy research obtained from the Internet and supplemented by available journals ...

Protein kinase Cɛ inhibition restores megakaryocytic differentiation of hematopoietic progenitors from primary myelofibrosis patients.

Science.gov (United States)

Masselli, E; Carubbi, C; Gobbi, G; Mirandola, P; Galli, D; Martini, S; Bonomini, S; Crugnola, M; Craviotto, L; Aversa, F; Vitale, M

2015-11-01

Among the three classic Philadelphia chromosome-negative myeloproliferative neoplasms, primary myelofibrosis (PMF) is the most severe in terms of disease biology, survival and quality of life. Abnormalities in the process of differentiation of PMF megakaryocytes (MKs) are a hallmark of the disease. Nevertheless, the molecular events that lead to aberrant megakaryocytopoiesis have yet to be clarified. Protein kinase Cɛ (PKCɛ) is a novel serine/threonine kinase that is overexpressed in a variety of cancers, promoting aggressive phenotype, invasiveness and drug resistance. Our previous findings on the role of PKCɛ in normal (erythroid and megakaryocytic commitment) and malignant (acute myeloid leukemia) hematopoiesis prompted us to investigate whether it could be involved in the pathogenesis of PMF MK-impaired differentiation. We demonstrate that PMF megakaryocytic cultures express higher levels of PKCɛ than healthy donors, which correlate with higher disease burden but not with JAK2V617F mutation. Inhibition of PKCɛ function (by a negative regulator of PKCɛ translocation) or translation (by target small hairpin RNA) leads to reduction in PMF cell growth, restoration of PMF MK differentiation and inhibition of PKCɛ-related anti-apoptotic signaling (Bcl-xL). Our data suggest that targeting PKCɛ directly affects the PMF neoplastic clone and represent a proof-of-concept for PKCɛ inhibition as a novel therapeutic strategy in PMF.

TFF1 inhibits proliferation and induces apoptosis of gastric cancer cells in vitro

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Yanli Ge

2012-05-01

Full Text Available Trefoil Factor Family (TFF plays an essential role in the intestinal epithelial restitution, but the relationship between TFF1 and gastric cancer (GC is still unclear. The present study aimed to determine the role of TFF1 in repairing gastric mucosa and in the pathogenesis of GC.The TFF1 expression in different gastric mucosas was measured with immunohistochemistry. Then, siRNA targeting TFF1 or plasmids expressing TFF1 gene were transfected into BGC823 cells, SGC7901 cells and GES-1 cells. The cell proliferation was detected with MTT assay and apoptosis and cell cycle measured by flow cytometry.From normal gastric mucosa to mucosa with dysplasia and to gastric cancer, the TFF1 expression had a decreasing trend. Down-regulation of TFF1 expression significantly reduced the apoptosis of three cell lines and markedly facilitated their proliferation but had no significant effect on cell cycle. Over-expression of TFF1 could promote apoptosis of three cell lines and inhibit proliferation but had no pronounced effect on cell cycle. TFF1 can inhibit proliferation and induce apoptosis of GC cells in vitro.

Biomechanical considerations in the pathogenesis of osteoarthritis of the knee

NARCIS (Netherlands)

Heijink, Andras; Gomoll, Andreas H.; Madry, Henning; Drobnič, Matej; Filardo, Giuseppe; Espregueira-Mendes, João; van Dijk, C. Niek

2012-01-01

Osteoarthritis is the most common joint disease and a major cause of disability. The knee is the large joint most affected. While chronological age is the single most important risk factor of osteoarthritis, the pathogenesis of knee osteoarthritis in the young patient is predominantly related to an

Neutrophil extracellular traps contribute to the pathogenesis of acid-aspiration-induced ALI/ARDS.

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Li, Haitao; Zhou, Xiaoting; Tan, Hongyi; Hu, Yongbin; Zhang, Lemeng; Liu, Shuai; Dai, Minhui; Li, Yi; Li, Qian; Mao, Zhi; Pan, Pinhua; Su, Xiaoli; Hu, Chengpin

2018-01-05

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a manifestation of systemic inflammation in the lungs, but the factors that trigger inflammation in ALI/ARDS are unclear. We hypothesized that neutrophil extracellular traps (NETs) contribute to the pathogenesis of acid aspiration-induced ALI/ARDS. Analysis of bronchial aspirates from ARDS patients showed that NETs were significantly correlated with the degree of ARDS (r = -0.5846, p = 0.0359). NETs in bronchoalveolar lavage fluid of acid-aspiration mice were significantly higher (141.6 ± 23.08) at 3 h after injury than those in the sham group (1234 ± 101.9; p = 0.003, n = 5 per group). Exogenous NETs aggravated lung injury, while alvelestat and DNase markedly attenuated the intensity of ARDS. We investigated whether NETs are involved in the severity of gastric aspiration-induced ARDS. Then, a hydrochloric acid aspiration-induced ALI murine model was used to assess whether NETs are pathogenic and whether targeting NETs is protective. Exogenous NETs were administered to mice. Alvelestat can inhibit neutrophil elastase (NE), which serves an important role in NET formation, so we investigated whether alvelestat could protect against ALI in cell and mouse models. NETs may contribute to ALI/ARDS by promoting tissue damage and systemic inflammation. Targeting NETs by alvelestat may be a potential therapeutic strategy.

Pathogenesis of thyroid autoimmune disease: the role of cellular mechanisms.

Science.gov (United States)

Ramos-Leví, Ana Maria; Marazuela, Mónica

2016-10-01

Hashimoto's thyroiditis (HT) and Graves' disease (GD) are two very common organ-specific autoimmune diseases which are characterized by circulating antibodies and lymphocyte infiltration. Although humoral and cellular mechanisms have been classically considered separately in the pathogenesis of autoimmune thyroid diseases (AITD), recent research suggests a close reciprocal relationship between these two immune pathways. Several B- and T-cell activation pathways through antigen-presenting cells (APCs) and cytokine production lead to specific differentiation of T helper (Th) and T regulatory (Treg) cells. This review will focus on the cellular mechanisms involved in the pathogenesis of AITD. Specifically, it will provide reasons for discarding the traditional simplistic dichotomous view of the T helper type 1 and 2 pathways (Th1/Th2) and will focus on the role of the recently characterized T cells, Treg and Th17 lymphocytes, as well as B lymphocytes and APCs, especially dendritic cells (DCs). Copyright © 2016 SEEN. Publicado por Elsevier España, S.L.U. All rights reserved.

Tissue and cellular tropism, pathology and pathogenesis of Ebola and Marburg viruses.

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Martines, Roosecelis Brasil; Ng, Dianna L; Greer, Patricia W; Rollin, Pierre E; Zaki, Sherif R

2015-01-01

Ebola viruses and Marburg viruses include some of the most virulent and fatal pathogens known to humans. These viruses cause severe haemorrhagic fevers, with case fatality rates in the range 25-90%. The diagnosis of filovirus using formalin-fixed tissues from fatal cases poses a significant challenge. The most characteristic histopathological findings are seen in the liver; however, the findings overlap with many other viral and non-viral haemorrhagic diseases. The need to distinguish filovirus infections from other haemorrhagic fevers, particularly in areas with multiple endemic viral haemorrhagic agents, is of paramount importance. In this review we discuss the current state of knowledge of filovirus infections and their pathogenesis, including histopathological findings, epidemiology, modes of transmission and filovirus entry and spread within host organisms. The pathogenesis of filovirus infections is complex and involves activation of the mononuclear phagocytic system, with release of pro-inflammatory cytokines, chemokines and growth factors, endothelial dysfunction, alterations of the innate and adaptive immune systems, direct organ and endothelial damage from unrestricted viral replication late in infection, and coagulopathy. Although our understanding of the pathogenesis of filovirus infections has rapidly increased in the past few years, many questions remain unanswered. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Transforming growth factor-β: activation by neuraminidase and role in highly pathogenic H5N1 influenza pathogenesis.

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Christina M Carlson

2010-10-01

Full Text Available Transforming growth factor-beta (TGF-β, a multifunctional cytokine regulating several immunologic processes, is expressed by virtually all cells as a biologically inactive molecule termed latent TGF-β (LTGF-β. We have previously shown that TGF-β activity increases during influenza virus infection in mice and suggested that the neuraminidase (NA protein mediates this activation. In the current study, we determined the mechanism of activation of LTGF-β by NA from the influenza virus A/Gray Teal/Australia/2/1979 by mobility shift and enzyme inhibition assays. We also investigated whether exogenous TGF-β administered via a replication-deficient adenovirus vector provides protection from H5N1 influenza pathogenesis and whether depletion of TGF-β during virus infection increases morbidity in mice. We found that both the influenza and bacterial NA activate LTGF-β by removing sialic acid motifs from LTGF-β, each NA being specific for the sialic acid linkages cleaved. Further, NA likely activates LTGF-β primarily via its enzymatic activity, but proteases might also play a role in this process. Several influenza A virus subtypes (H1N1, H1N2, H3N2, H5N9, H6N1, and H7N3 except the highly pathogenic H5N1 strains activated LTGF-β in vitro and in vivo. Addition of exogenous TGF-β to H5N1 influenza virus-infected mice delayed mortality and reduced viral titers whereas neutralization of TGF-β during H5N1 and pandemic 2009 H1N1 infection increased morbidity. Together, these data show that microbe-associated NAs can directly activate LTGF-β and that TGF-β plays a pivotal role protecting the host from influenza pathogenesis.

The Role of microRNAs in the Pathogenesis of Herpesvirus Infection.

Science.gov (United States)

Piedade, Diogo; Azevedo-Pereira, José Miguel

2016-06-02

MicroRNAs (miRNAs) are small non-coding RNAs important in gene regulation. They are able to regulate mRNA translation through base-pair complementarity. Cellular miRNAs have been involved in the regulation of nearly all cellular pathways, and their deregulation has been associated with several diseases such as cancer. Given the importance of microRNAs to cell homeostasis, it is no surprise that viruses have evolved to take advantage of this cellular pathway. Viruses have been reported to be able to encode and express functional viral microRNAs that target both viral and cellular transcripts. Moreover, viral inhibition of key proteins from the microRNA pathway and important changes in cellular microRNA pool have been reported upon viral infection. In addition, viruses have developed multiple mechanisms to avoid being targeted by cellular microRNAs. This complex interaction between host and viruses to control the microRNA pathway usually favors viral infection and persistence by either reducing immune detection, avoiding apoptosis, promoting cell growth, or promoting lytic or latent infection. One of the best examples of this virus-host-microRNA interplay emanates from members of the Herperviridae family, namely the herpes simplex virus type 1 and type 2 (HSV-1 and HSV-2), human cytomegalovirus (HCMV), human herpesvirus 8 (HHV-8), and the Epstein-Barr virus (EBV). In this review, we will focus on the general functions of microRNAs and the interactions between herpesviruses, human hosts, and microRNAs and will delve into the related mechanisms that contribute to infection and pathogenesis.

The Emerging Role of Zinc in the Pathogenesis of Multiple Sclerosis

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Bo Young Choi

2017-09-01

Full Text Available Our lab has previously demonstrated that multiple sclerosis-induced spinal cord white matter damage and motor deficits are mediated by the pathological disruption of zinc homeostasis. Abnormal vesicular zinc release and intracellular zinc accumulation may mediate several steps in the pathophysiological processes of multiple sclerosis (MS, such as matrix metallopeptidase 9 (MMP-9 activation, blood-brain barrier (BBB disruption, and subsequent immune cell infiltration from peripheral systems. Oral administration of a zinc chelator decreased BBB disruption, immune cell infiltration, and spinal white matter myelin destruction. Therefore, we hypothesized that zinc released into the extracellular space during MS progression is involved in destruction of the myelin sheath in spinal cord white mater and in generation of motor deficits. To confirm our previous study, we employed zinc transporter 3 (ZnT3 knockout mice to test whether vesicular zinc depletion shows protective effects on multiple sclerosis-induced white matter damage and motor deficits. ZnT3 gene deletion profoundly reduced the daily clinical score of experimental autoimmune encephalomyelitis (EAE by suppression of inflammation and demyelination in the spinal cord. ZnT3 gene deletion also remarkably inhibited formation of multiple sclerosis-associated aberrant synaptic zinc patches, MMP-9 activation, and BBB disruption. These two studies strongly support our hypothesis that zinc release from presynaptic terminals may be involved in multiple sclerosis pathogenesis. Further studies will no doubt continue to add mechanistic detail to this process and with luck, clarify how these observations may lead to development of novel therapeutic approaches for the treatment of multiple sclerosis.

The Emerging Role of Zinc in the Pathogenesis of Multiple Sclerosis.

Science.gov (United States)

Choi, Bo Young; Jung, Jong Won; Suh, Sang Won

2017-09-28

Our lab has previously demonstrated that multiple sclerosis-induced spinal cord white matter damage and motor deficits are mediated by the pathological disruption of zinc homeostasis. Abnormal vesicular zinc release and intracellular zinc accumulation may mediate several steps in the pathophysiological processes of multiple sclerosis (MS), such as matrix metallopeptidase 9 (MMP-9) activation, blood-brain barrier (BBB) disruption, and subsequent immune cell infiltration from peripheral systems. Oral administration of a zinc chelator decreased BBB disruption, immune cell infiltration, and spinal white matter myelin destruction. Therefore, we hypothesized that zinc released into the extracellular space during MS progression is involved in destruction of the myelin sheath in spinal cord white mater and in generation of motor deficits. To confirm our previous study, we employed zinc transporter 3 ( ZnT3 ) knockout mice to test whether vesicular zinc depletion shows protective effects on multiple sclerosis-induced white matter damage and motor deficits. ZnT3 gene deletion profoundly reduced the daily clinical score of experimental autoimmune encephalomyelitis (EAE) by suppression of inflammation and demyelination in the spinal cord. ZnT3 gene deletion also remarkably inhibited formation of multiple sclerosis-associated aberrant synaptic zinc patches, MMP-9 activation, and BBB disruption. These two studies strongly support our hypothesis that zinc release from presynaptic terminals may be involved in multiple sclerosis pathogenesis. Further studies will no doubt continue to add mechanistic detail to this process and with luck, clarify how these observations may lead to development of novel therapeutic approaches for the treatment of multiple sclerosis.

Porcine Circovirus-Like Virus P1 Inhibits Wnt Signaling Pathway in Vivo and in Vitro.

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Zhu, Xuejiao; Wen, Libin; Sheng, Shaoyang; Wang, Wei; Xiao, Qi; Qu, Meng; Hu, Yiyi; Liu, Chuanmin; He, Kongwang

2018-01-01

Porcine circovirus-like virus P1 is an important pathogen of the current pig industry, the infection mechanism is not entirely clear. Wnt signaling pathway plays an important role in the growth of young animals and infection of some viruses. This study was designed to demonstrate the effects of P1 infection on the Wnt signaling pathway. In vivo experiments, we demonstrated the down-regulatory effects of P1 infection in piglets and mice on the downstream components expression levels of Wnt signaling pathway, and the effects of Wnt signaling pathway activation on the pathogenesis of P1. In vitro studies, we found P1 infection down-regulated protein level of β-catenin and mRNA level of mmp2, prevented the β-catenin from entering into nucleus, abolished the TCF/LEF promoter activity, proved that P1 could inhibit the activation of Wnt signaling pathway in vitro . Finally, we found that VP1 of P1 virus also had the inhibitory effects on Wnt signaling pathway in vitro , elucidated the mechanism of P1's inhibitory effects on the Wnt signaling pathway and offered the possibility that the suppression of Wnt signaling pathway was involved in the post-weaning multisystemic wasting syndrome (PMWS), laying a foundation for elucidating the pathogenesis of P1.

Role of Endogenous Peptides and Enzymes in the Pathogenesis of ...

African Journals Online (AJOL)

Acute pancreatitis is an inflammatory disease with the clinical manifestation of acute abdominal pain. Several factors are involved in the pathogenesis of acute pancreatitis. The exact mechanism(s) by which diverse etiological factors induce an attack are still unclear. However, one of the proposed mechanisms for induction ...

ER Stress and β-Cell Pathogenesis of Type 1 and Type 2 Diabetes and Islet Transplantation

OpenAIRE

Kataoka, Hitomi Usui; Noguchi, Hirofumi

2013-01-01

Endoplasmic reticulum (ER) stress affects the pathogenesis of diabetes. ER stress plays important roles, both in type 1 and type 2 diabetes, because pancreatic β-cells possess highly developed ER for insulin secretion. This review summarizes the relationship between ER stress and the pathogenesis of type 1 and type 2 diabetes. In addition, the association between islet transplantation and ER stress is discussed.

Psilocybin-induced deficits in automatic and controlled inhibition are attenuated by ketanserin in healthy human volunteers.

Science.gov (United States)

Quednow, Boris B; Kometer, Michael; Geyer, Mark A; Vollenweider, Franz X

2012-02-01

The serotonin-2A receptor (5-HT(2A)R) has been implicated in the pathogenesis of schizophrenia and related inhibitory gating and behavioral inhibition deficits of schizophrenia patients. The hallucinogen psilocybin disrupts automatic forms of sensorimotor gating and response inhibition in humans, but it is unclear so far whether the 5-HT(2A)R or 5-HT(1A)R agonist properties of its bioactive metabolite psilocin account for these effects. Thus, we investigated whether psilocybin-induced deficits in automatic and controlled inhibition in healthy humans could be attenuated by the 5-HT(2A/2C)R antagonist ketanserin. A total of 16 healthy participants received placebo, ketanserin (40 mg p.o.), psilocybin (260 μg/kg p.o.), or psilocybin plus ketanserin in a double-blind, randomized, and counterbalanced order. Sensorimotor gating was measured by prepulse inhibition (PPI) of the acoustic startle response. The effects on psychopathological core dimensions and behavioral inhibition were assessed by the altered states of consciousness questionnaire (5D-ASC), and the Color-Word Stroop Test. Psilocybin decreased PPI at short lead intervals (30 ms), increased all 5D-ASC scores, and selectively increased errors in the interference condition of the Stroop Test. Stroop interference and Stroop effect of the response latencies were increased under psilocybin as well. Psilocybin-induced alterations were attenuated by ketanserin pretreatment, whereas ketanserin alone had no significant effects. These findings suggest that the disrupting effects of psilocybin on automatic and controlled inhibition processes are attributable to 5-HT(2A)R stimulation. Sensorimotor gating and attentional control deficits of schizophrenia patients might be due to changes within the 5-HT(2A)R system.

Biological roles of cysteine proteinases in the pathogenesis of Trichomonas vaginalis

Science.gov (United States)

Hernández, Hilda M.; Marcet, Ricardo; Sarracent, Jorge

2014-01-01

Human trichomonosis, infection with Trichomonas vaginalis, is the most common non-viral sexually transmitted disease in the world. The host-parasite interaction and pathophysiological processes of trichomonosis remain incompletely understood. This review focuses on the advancements reached in the area of the pathogenesis of T. vaginalis, especially in the role of the cysteine proteinases. It highlights various approaches made in this field and lists a group of trichomonad cysteine proteinases involved in diverse processes such as invasion of the mucous layer, cytoadherence, cytotoxicity, cytoskeleton disruption of red blood cells, hemolysis, and evasion of the host immune response. A better understanding of the biological roles of cysteine proteinases in the pathogenesis of this parasite could be used in the identification of new chemotherapeutic targets. An additional advantage could be the development of a vaccine in order to reduce transmission of T. vaginalis. PMID:25348828

A review of the role of oxidative stress in the pathogenesis of eye diseases

Directory of Open Access Journals (Sweden)

O. A. Oduntan

2011-12-01

Full Text Available Free radicals, referred to as oxidants are molecules in the body with unpaired electrons, hence are unstable and ready to bond with other molecules with unpaired electrons.  They include Reactive Oxygen Species (ROS such as superoxide anion radicals (·O¯, hydrogen peroxide (H202, and hydroxyl free radicals (·OH.  Endogenous sources of ROS include metabolic and other organic processes, while exogenous sources include ultraviolet radiation and environmental toxins such as smoke.  Antioxidants (oxidant scavengers such as ascorbate, alpha-tocopherol and glutathione as well as various enzymatic compounds such as superoxide dismutase (SOD, catalase and glutathione reductase are also present in the body and in manyfoods or food supplements.  An imbalance between oxidants and antioxidants in favour of oxidantsis termed oxidative stress and can lead to cell or tissue damage and aging. Oxidative stress has been implicated in the pathogenesis of many serious systemic diseases such as diabetes, cancer and neurological disorders.  Also, laboratory and epidemiological studies have implicated oxidative stress in the pathogenesis of the majority of common serious eye diseases such as cataract, primary open angle glaucoma and age-related macular degeneration. In this article, we reviewed the current information on the roles of oxidative stress in the pathogenesis of various eye diseases and the probable roles of antioxidants.  Eye care practitioners will find this article useful as it provides information on the pathogenesis of common eye diseases. (S Afr Optom 2011 70(4 182-190

Inhibition of GSK-3 ameliorates Abeta pathology in an adult-onset Drosophila model of Alzheimer's disease.

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Oyinkan Sofola

2010-09-01

Full Text Available Abeta peptide accumulation is thought to be the primary event in the pathogenesis of Alzheimer's disease (AD, with downstream neurotoxic effects including the hyperphosphorylation of tau protein. Glycogen synthase kinase-3 (GSK-3 is increasingly implicated as playing a pivotal role in this amyloid cascade. We have developed an adult-onset Drosophila model of AD, using an inducible gene expression system to express Arctic mutant Abeta42 specifically in adult neurons, to avoid developmental effects. Abeta42 accumulated with age in these flies and they displayed increased mortality together with progressive neuronal dysfunction, but in the apparent absence of neuronal loss. This fly model can thus be used to examine the role of events during adulthood and early AD aetiology. Expression of Abeta42 in adult neurons increased GSK-3 activity, and inhibition of GSK-3 (either genetically or pharmacologically by lithium treatment rescued Abeta42 toxicity. Abeta42 pathogenesis was also reduced by removal of endogenous fly tau; but, within the limits of detection of available methods, tau phosphorylation did not appear to be altered in flies expressing Abeta42. The GSK-3-mediated effects on Abeta42 toxicity appear to be at least in part mediated by tau-independent mechanisms, because the protective effect of lithium alone was greater than that of the removal of tau alone. Finally, Abeta42 levels were reduced upon GSK-3 inhibition, pointing to a direct role of GSK-3 in the regulation of Abeta42 peptide level, in the absence of APP processing. Our study points to the need both to identify the mechanisms by which GSK-3 modulates Abeta42 levels in the fly and to determine if similar mechanisms are present in mammals, and it supports the potential therapeutic use of GSK-3 inhibitors in AD.

miR-125b-1-3p inhibits trophoblast cell invasion by targeting sphingosine-1-phosphate receptor 1 in preeclampsia.

Science.gov (United States)

Li, Qinghua; Pan, Zhifang; Wang, Xuejian; Gao, Zhiqin; Ren, Chune; Yang, Weiwei

2014-10-10

Preeclampsia (PE) is the leading cause of maternal and perinatal mortality and morbidity. Understanding the molecular mechanisms underlying placentation facilitates the development of better intervention of this disease. MicroRNAs are strongly implicated in the pathogenesis of this syndrome. In current study, we found that miR-125b-1-3p was elevated in placentas derived from preeclampsia patients. Transfection of miR-125b-1-3p mimics significantly inhibited the invasiveness of human trophoblast cells, whereas miR-125b-1-3p inhibitor enhanced trophoblast cell invasion. Luciferase assays identified that S1PR1 was a novel direct target of miR-125b-1-3p in the placenta. Overexpression of S1PR1 could reverse the inhibitory effect of miR-125b-1-3p on the invasion of trophoblast cells. These findings suggested that abnormal expression of miR-125b-1-3p might contribute to the pathogenesis of preeclampsia. Copyright © 2014 Elsevier Inc. All rights reserved.

MicroRNAs in the pathogenesis of cystic kidney disease.

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Phua, Yu Leng; Ho, Jacqueline

2015-04-01

Cystic kidney diseases are common renal disorders characterized by the formation of fluid-filled epithelial cysts in the kidneys. The progressive growth and expansion of the renal cysts replace existing renal tissue within the renal parenchyma, leading to reduced renal function. While several genes have been identified in association with inherited causes of cystic kidney disease, the molecular mechanisms that regulate these genes in the context of post-transcriptional regulation are still poorly understood. There is increasing evidence that microRNA (miRNA) dysregulation is associated with the pathogenesis of cystic kidney disease. In this review, recent studies that implicate dysregulation of miRNA expression in cystogenesis will be discussed. The relationship of specific miRNAs, such as the miR-17∼92 cluster and cystic kidney disease, miR-92a and von Hippel-Lindau syndrome, and alterations in LIN28-LET7 expression in Wilms tumor will be explored. At present, there are no specific treatments available for patients with cystic kidney disease. Understanding and identifying specific miRNAs involved in the pathogenesis of these disorders may have the potential to lead to the development of novel therapies and biomarkers.

Review article: Pathogenesis and management of gastric carcinoid tumours.

Science.gov (United States)

Burkitt, M D; Pritchard, D M

2006-11-01

Gastric carcinoid tumours are rare, but are increasing in incidence. To discuss tumour pathogenesis and outline current approaches to patient management. Review of published articles following a Pubmed search. Although interest in gastric carcinoids has increased since it was recognized that they are associated with achlorhydria, to date there is no definite evidence that humans taking long-term acid suppressing medication are at increased risk. Type I tumours are associated with autoimmune atrophic gastritis and hypergastrinaemia, type II are associated with Zollinger-Ellison syndrome, multiple endocrine neoplasia-1 and hypergastrinaemia and sporadic type III carcinoids are gastrin-independent and carry the worst prognosis. Careful investigation of these patients is required, particularly to identify the tumour type, the source of hypergastrinaemia and the presence of metastases. Treatment can be directed at the source of hypergastrinaemia if type I or II tumours are still gastrin responsive and not growing autonomously. Type III tumours should be treated surgically. Advances in our understanding of the pathogenesis of gastric carcinoids have led to recent improvements in investigation and management. Challenges remain in identifying the genetic and environmental factors, in addition to hypergastrinaemia, that are responsible for tumour development in susceptible patients.

Pathogenesis of post-traumatic ankylosis of the temporomandibular joint: a critical review.

Science.gov (United States)

Arakeri, Gururaj; Kusanale, Atul; Zaki, Graeme A; Brennan, Peter A

2012-01-01

Many factors have been implicated in the development of bony ankylosis following trauma to the temporomandibular joint (TMJ) or ankylosis that recurs after surgical treatment for the condition. Although many reports have been published, to our knowledge very little has been written about the pathogenesis of the process and there are few scientific studies. Over the last 70 years various treatments have been described. Different methods have been used with perceived favourable outcomes although recurrence remains a problem in many cases, and ankylosis presents a major therapeutic challenge. We present a critical review of published papers and discuss the various hypotheses regarding the pathogenesis of the condition. Copyright © 2010 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Integral Role of PTP1B in Adiponectin-Mediated Inhibition of Oncogenic Actions of Leptin in Breast Carcinogenesis

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LaTonia Taliaferro-Smith

2013-01-01

Full Text Available The molecular effects of obesity are mediated by alterations in the levels of adipocytokines. High leptin level associated with obese state is a major cause of breast cancer progression and metastasis, whereas adiponectin is considered a “guardian angel adipocytokine” for its protective role against various obesity-related pathogenesis including breast cancer. In the present study, investigating the role of adiponectin as a potential inhibitor of leptin, we show that adiponectin treatment inhibits leptin-induced clonogenicity and anchorage-independent growth. Leptin-stimulated migration and invasion of breast cancer cells is also effectively inhibited by adiponectin. Analyses of the underlying molecular mechanisms reveal that adiponectin suppresses activation of two canonical signaling molecules of leptin signaling axis: extracellular signal-regulated kinase (ERK and Akt. Pretreatment of breast cancer cells with adiponectin protects against leptin-induced activation of ERK and Akt. Adiponectin increases expression and activity of the physiological inhibitor of leptin signaling, protein tyrosine phosphatase 1B (PTP1B, which is found to be integral to leptin-antagonist function of adiponectin. Inhibition of PTP1B blocks adiponectin-mediated inhibition of leptin-induced breast cancer growth. Our in vivo studies show that adenovirus-mediated adiponectin treatment substantially reduces leptin-induced mammary tumorigenesis in nude mice. Exploring therapeutic strategies, we demonstrate that treatment of breast cancer cells with rosiglitazone results in increased adiponectin expression and inhibition of migration and invasion. Rosiglitazone treatment also inhibits leptin-induced growth of breast cancer cells. Taken together, these data show that adiponectin treatment can inhibit the oncogenic actions of leptin through blocking its downstream signaling molecules and raising adiponectin levels could be a rational therapeutic strategy for breast

The pathogenesis of HIV infection: stupid may not be so dumb after all

Directory of Open Access Journals (Sweden)

Smith Stephen M

2006-09-01

Full Text Available Abstract In the mid-1990's, researchers hypothesized, based on new viral load data, that HIV-1 causes CD4+ T-cell depletion by direct cytopathic effect. New data from non-human primate studies has raised doubts about this model of HIV-1 pathogenesis. Despite having high levels of viremia, most SIV infections are well tolerated by their natural hosts. Two recent studies of these models provide information, which may be useful in determining how HIV-1 causes CD4+ T-cell loss. A full understanding of pathogenesis may lead to novel therapies, which preserve the immune system without blocking virus replication.

Feline Coronaviruses: Pathogenesis of Feline Infectious Peritonitis.

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Tekes, G; Thiel, H-J

2016-01-01

Feline infectious peritonitis (FIP) belongs to the few animal virus diseases in which, in the course of a generally harmless persistent infection, a virus acquires a small number of mutations that fundamentally change its pathogenicity, invariably resulting in a fatal outcome. The causative agent of this deadly disease, feline infectious peritonitis virus (FIPV), arises from feline enteric coronavirus (FECV). The review summarizes our current knowledge of the genome and proteome of feline coronaviruses (FCoVs), focusing on the viral surface (spike) protein S and the five accessory proteins. We also review the current classification of FCoVs into distinct serotypes and biotypes, cellular receptors of FCoVs and their presumed role in viral virulence, and discuss other aspects of FIPV-induced pathogenesis. Our current knowledge of genetic differences between FECVs and FIPVs has been mainly based on comparative sequence analyses that revealed "discriminatory" mutations that are present in FIPVs but not in FECVs. Most of these mutations result in amino acid substitutions in the S protein and these may have a critical role in the switch from FECV to FIPV. In most cases, the precise roles of these mutations in the molecular pathogenesis of FIP have not been tested experimentally in the natural host, mainly due to the lack of suitable experimental tools including genetically engineered virus mutants. We discuss the recent progress in the development of FCoV reverse genetics systems suitable to generate recombinant field viruses containing appropriate mutations for in vivo studies. © 2016 Elsevier Inc. All rights reserved.

TW-01, a piperazinedione-derived compound, inhibits Ras-mediated cell proliferation and angioplasty-induced vascular restenosis

Energy Technology Data Exchange (ETDEWEB)

Lin, Chao-Feng [The Ph.D. Program for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 11031, Taiwan (China); Department of Medicine, MacKay Medical College, New Taipei City, Taiwan (China); Division of Cardiology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan (China); Division of Cardiology, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan (China); Huang, Han-Li [The Ph.D. Program for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 11031, Taiwan (China); Peng, Chieh-Yu [Chinese Medicine Research and Development Center, China Medical University Hospital, Taichung 404, Taiwan (China); School of Pharmacy, College of Pharmacy, China Medical University, Taichung 404, Taiwan (China); Lee, Yu-Ching [The Center of Translational Medicine, Taipei Medical University, Taipei, Taiwan (China); Ph.D. Program for Biotechnology in Medicine, Taipei Medical University, Taipei, Taiwan (China); Wang, Hui-Po [College of Pharmacy, Taipei Medical University, Taipei 11031, Taiwan (China); Teng, Che-Ming [College of Pharmacy, Taipei Medical University, Taipei 11031, Taiwan (China); Pharmacological Institute, College of Medicine, National Taiwan University, Taipei 100, Taiwan (China); Pan, Shiow-Lin, E-mail: slpan@tmu.edu.tw [The Ph.D. Program for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 11031, Taiwan (China); Department of Pharmacology, College of Medicine, Taipei Medical University, Taipei 10031, Taiwan (China)

2016-08-15

Purpose: Vascular smooth muscle cell (VSMC) proliferation plays a critical role in the pathogenesis of atherosclerosis and restenosis. This study investigated piperazinedione derived compound TW-01-mediated inhibitory effects on VSMC proliferation and intimal hyperplasia. Methods: Cell proliferation was determined using [{sup 3}H]-thymidine incorporation and MTT assay; cell cycle distribution was measured using flow cytometry; proteins and mRNA expression were determined using western blotting and RT-PCR analyses; DNA binding activity of nuclear factor-κB (NF-κB), as measured using enzyme-linked immunosorbent assays (ELISA); in vivo effects of TW-01 were determined using balloon angioplasty in the rat. Results: TW-01 significantly inhibited cell proliferation. At the concentrations used, no cytotoxic effects were observed. Three predominant signaling pathways were inhibited by TW-01: (a) extracellular signal-regulated kinase (ERK)1/2 mitogen-activated protein kinase (MAPK) activation and its downstream effectors of c-fos, c-jun, and c-myc; (b) DNA binding activity of nuclear factor-κB (NF-κB); and, (c) Akt/protein kinase B (PKB) and cell cycle progression. Furthermore, TW-01 also inhibited Ras activation, a shared upstream event of each of these signaling cascades. In vascular injury studies, oral administration of TW-01 significantly suppressed intimal hyperplasia induced by balloon angioplasty. Conclusion: The present study suggests that TW-01 might be a potential candidate for atherosclerosis treatment. - Highlights: • TW-01significantly inhibits vascular smooth muscle cell proliferation. • TW-01 inhibits ERK, Akt and Ras pathway and DNA binding activity of NF-κB. • TW-01 significantly suppresses intimal hyperplasia induced by balloon angioplasty. • TW-01 might be a potential candidate for atherosclerosis treatment.

TW-01, a piperazinedione-derived compound, inhibits Ras-mediated cell proliferation and angioplasty-induced vascular restenosis

International Nuclear Information System (INIS)

Lin, Chao-Feng; Huang, Han-Li; Peng, Chieh-Yu; Lee, Yu-Ching; Wang, Hui-Po; Teng, Che-Ming; Pan, Shiow-Lin

2016-01-01

Purpose: Vascular smooth muscle cell (VSMC) proliferation plays a critical role in the pathogenesis of atherosclerosis and restenosis. This study investigated piperazinedione derived compound TW-01-mediated inhibitory effects on VSMC proliferation and intimal hyperplasia. Methods: Cell proliferation was determined using [ 3 H]-thymidine incorporation and MTT assay; cell cycle distribution was measured using flow cytometry; proteins and mRNA expression were determined using western blotting and RT-PCR analyses; DNA binding activity of nuclear factor-κB (NF-κB), as measured using enzyme-linked immunosorbent assays (ELISA); in vivo effects of TW-01 were determined using balloon angioplasty in the rat. Results: TW-01 significantly inhibited cell proliferation. At the concentrations used, no cytotoxic effects were observed. Three predominant signaling pathways were inhibited by TW-01: (a) extracellular signal-regulated kinase (ERK)1/2 mitogen-activated protein kinase (MAPK) activation and its downstream effectors of c-fos, c-jun, and c-myc; (b) DNA binding activity of nuclear factor-κB (NF-κB); and, (c) Akt/protein kinase B (PKB) and cell cycle progression. Furthermore, TW-01 also inhibited Ras activation, a shared upstream event of each of these signaling cascades. In vascular injury studies, oral administration of TW-01 significantly suppressed intimal hyperplasia induced by balloon angioplasty. Conclusion: The present study suggests that TW-01 might be a potential candidate for atherosclerosis treatment. - Highlights: • TW-01significantly inhibits vascular smooth muscle cell proliferation. • TW-01 inhibits ERK, Akt and Ras pathway and DNA binding activity of NF-κB. • TW-01 significantly suppresses intimal hyperplasia induced by balloon angioplasty. • TW-01 might be a potential candidate for atherosclerosis treatment.

[EBOLA HEMORRHAGIC FEVER; ETIOLOGY, EPIDEMIOLOGY, PATHOGENESIS, AND CLINICAL SYMPTOMS].

Science.gov (United States)

Zhdanov, K W; Zakharenko, S M; Kovalenko, A N; Semenov, A V; Fusin, A Ya

2015-01-01

The data on the prevalence of disease caused by Ebola virus, biological features of its pathogen, character of the epidemiological process, pathogenesis and clinical symptoms are presented. The disease is characterized by suppression of protective immunological mechanisms and systemic inflammatory reaction accounting for the lesions of vascular endothelium, hemostatic and immune systems. It eventually leads to polyorgan insufficiency and severe shock. Lethality amounts to 50%.

The fundamental role of endothelial cells in hantavirus pathogenesis

OpenAIRE

Hepojoki, Jussi; Vaheri, Antti; Strandin, Tomas

2014-01-01

Hantavirus, a genus of rodent- and insectivore-borne viruses in the family Bunyaviridae, is a group of emerging zoonotic pathogens. Hantaviruses cause hemorrhagic fever with renal syndrome and hantavirus cardiopulmonary syndrome in man, often with severe consequences. Vascular leakage is evident in severe hantavirus infections, and increased permeability contributes to the pathogenesis. This review summarizes the current knowledge on hantavirus interactions with hematopoietic and endothelial ...

Methylmercury inhibits gap junctional intercellular communication in primary cultures of rat proximal tubular cells

Energy Technology Data Exchange (ETDEWEB)

Yoshida, Minoru; Sumi, Yawara [Department of Chemistry, St. Marianna University School of Medicine, Kawasagi (Japan); Kujiraoka, Toru [Department of Physiology, St. Marianna University School of Medicine, Kawasagi (Japan); Hara, Masayuki [Department of Anatomy, St. Marianna University School of Medicine, Kawasagi (Japan); Nakazawa, Hirokazu [Department of Chemistry, Faculty of Sciences, Meisei University (Japan)

1998-03-01

Methylmercury (MeHg) causes renal injury in addition to central and peripheral neuropathy. To clarify the mechanism of nephrotoxicity by MeHg, we investigated the effect of this compound on intercellular communication through gap junction channels in primary cultures of rat renal proximal tubular cells. Twenty minutes after exposure to 30 {mu}M MeHg, gap junctional intercellular communication (GJIC), which was assessed by dye coupling, was markedly inhibited before appearance of cytotoxicity. When the medium containing MeHg was exchanged with MeHg-free medium, dye coupling recovered abruptly. However, the dye-coupling was abolished again 30 min after replacement with control medium, and the cells were damaged. Intracellular calcium concentration, [Ca{sup 2+}]{sub i}, which modulates the function of gap junctions, significantly increased following exposure of the cells to 30 {mu}M MeHg and returned to control level following replacement with MeHg-free medium. These results suggest that the inhibiting effect of MeHg on GJIC is related to the change in [Ca{sup 2+}]{sub i}, and may be involved in the pathogenesis of renal dysfunction. (orig.) With 5 figs., 23 refs.

Inhibition of Rac controls NPM–ALK-dependent lymphoma development and dissemination

Energy Technology Data Exchange (ETDEWEB)

Colomba, A [INSERM, U1048, Université Toulouse III, Toulouse, Institut des Maladies Métaboliques et Cardiovasculaires, Toulouse (France); Giuriato, S; Dejean, E [Centre de Recherches en Cancérologie de Toulouse, UMR1037-Université Toulouse III, IFR150-IFRBMT, Toulouse (France); Thornber, K [INSERM, U1048, Université Toulouse III, Toulouse, Institut des Maladies Métaboliques et Cardiovasculaires, Toulouse (France); Delsol, G [Centre de Recherches en Cancérologie de Toulouse, UMR1037-Université Toulouse III, IFR150-IFRBMT, Toulouse (France); Tronchère, H [INSERM, U1048, Université Toulouse III, Toulouse, Institut des Maladies Métaboliques et Cardiovasculaires, Toulouse (France); Meggetto, F [Centre de Recherches en Cancérologie de Toulouse, UMR1037-Université Toulouse III, IFR150-IFRBMT, Toulouse (France); Payrastre, B; Gaits-Iacovoni, F [INSERM, U1048, Université Toulouse III, Toulouse, Institut des Maladies Métaboliques et Cardiovasculaires, Toulouse (France)

2011-06-01

Nucleophosmin-anaplastic lymphoma kinase (NPM–ALK) is a tyrosine kinase oncogene responsible for the pathogenesis of the majority of human ALK-positive lymphomas. We recently reported that it activated the Rac1 GTPase in anaplastic large-cell lymphoma (ALCL), leading to Rac-dependent formation of active invadopodia required for invasiveness. Herein, we went further into the study of this pathway and used the inhibitor of Rac, NSC23766, to validate its potential as a molecular target in ALCL in vitro and in vivo in a xenograft model and in a conditional model of NPM–ALK transgenic mice. Our data demonstrate that Rac regulates important effectors of NPM–ALK-induced transformation such as Erk1/2, p38 and Akt. Moreover, inhibition of Rac signaling abrogates NPM–ALK-elicited disease progression and metastasis in mice, highlighting the potential of small GTPases and their regulators as additional therapic targets in lymphomas.

Inhibition of Rac controls NPM–ALK-dependent lymphoma development and dissemination

International Nuclear Information System (INIS)

Colomba, A; Giuriato, S; Dejean, E; Thornber, K; Delsol, G; Tronchère, H; Meggetto, F; Payrastre, B; Gaits-Iacovoni, F

2011-01-01

Nucleophosmin-anaplastic lymphoma kinase (NPM–ALK) is a tyrosine kinase oncogene responsible for the pathogenesis of the majority of human ALK-positive lymphomas. We recently reported that it activated the Rac1 GTPase in anaplastic large-cell lymphoma (ALCL), leading to Rac-dependent formation of active invadopodia required for invasiveness. Herein, we went further into the study of this pathway and used the inhibitor of Rac, NSC23766, to validate its potential as a molecular target in ALCL in vitro and in vivo in a xenograft model and in a conditional model of NPM–ALK transgenic mice. Our data demonstrate that Rac regulates important effectors of NPM–ALK-induced transformation such as Erk1/2, p38 and Akt. Moreover, inhibition of Rac signaling abrogates NPM–ALK-elicited disease progression and metastasis in mice, highlighting the potential of small GTPases and their regulators as additional therapic targets in lymphomas

Polycystic Kidney Disease: Pathogenesis and Potential Therapies

Science.gov (United States)

Takiar, Vinita; Caplan, Michael J.

2011-01-01

Autosomal dominant polycystic kidney disease (ADPKD) is a prevalent, inherited condition for which there is currently no effective specific clinical therapy. The disease is characterized by the progressive development of fluid-filled cysts derived from renal tubular epithelial cells which gradually compress the parenchyma and compromise renal function. Current interests in the field focus on understanding and exploiting signaling mechanisms underlying disease pathogenesis as well as delineating the role of the primary cilium in cystogenesis. This review highlights the pathogenetic pathways underlying renal cyst formation as well as novel therapeutic targets for the treatment of PKD. PMID:21146605

Molecular pathogenesis and mechanisms of thyroid cancer

Science.gov (United States)

Xing, Mingzhao

2013-01-01

Thyroid cancer is a common endocrine malignancy. There has been exciting progress in understanding its molecular pathogenesis in recent years, as best exemplified by the elucidation of the fundamental role of several major signalling pathways and related molecular derangements. Central to these mechanisms are the genetic and epigenetic alterations in these pathways, such as mutation, gene copy-number gain and aberrant gene methylation. Many of these molecular alterations represent novel diagnostic and prognostic molecular markers and therapeutic targets for thyroid cancer, which provide unprecedented opportunities for further research and clinical development of novel treatment strategies for this cancer. PMID:23429735

Involvement of regulatory T cells and selected cytokines in the pathogenesis of bronchial asthma

Directory of Open Access Journals (Sweden)

Monika Zuśka-Prot

2016-06-01

Full Text Available Asthma pathogenesis is complex and involves the interplay of many factors and actions. Airway inflammation in allergic asthma is characterized by an exaggerated activation of T helper type 2 cells, IgE production and infiltration and activation of eosinophils. The results of studies conducted in recent years indicate that the deficit of naturally occurring Foxp3+CD25+CD4+ and Foxp3+CD25+CD8+ regulatory T cells and type 1 regulatory T cells plays a pivotal role in the development of this disease. Moreover, numerous studies have provided convincing evidence that a decrease in IL-10 production and an increase in IL-17 production have an important place in the pathophysiology of asthma. TGF-β is another important cytokine involved in this disease. TGF-β has a paradoxical status in relation to asthma pathogenesis because it seems to play a role in both suppressing and promoting asthma development. This review discusses briefly clinical and experimental data concerning the involvement of T regulatory cells and IL-10, IL-17 and TGF-β in the pathogenesis of asthma.

Multi-platform ’Omics Analysis of Human Ebola Virus Disease Pathogenesis

Energy Technology Data Exchange (ETDEWEB)

Eisfeld, Amie J.; Halfmann, Peter J.; Wendler, Jason P.; Kyle, Jennifer E.; Burnum-Johnson, Kristin E.; Peralta, Zuleyma; Maemura, Tadashi; Walters, Kevin B.; Watanabe, Tokiko; Fukuyama, Satoshi; Yamashita, Makoto; Jacobs, Jon M.; Kim, Young-Mo; Casey, Cameron P.; Stratton, Kelly G.; Webb-Robertson, Bobbie-Jo M.; Gritsenko, Marina A.; Monroe, Matthew E.; Weitz, Karl K.; Shukla, Anil K.; Tian, Mingyuan; Neumann, Gabriele; Reed, Jennifer L.; van Bakel, Harm; Metz, Thomas O.; Smith, Richard D.; Waters, Katrina M.; N' jai, Alhaji; Sahr, Foday; Kawaoka, Yoshihiro

2017-12-01

The pathogenesis of human Ebola virus disease (EVD) is complex. EVD is characterized by high levels of virus replication and dissemination, dysregulated immune responses, extensive virus- and host-mediated tissue damage, and disordered coagulation. To clarify how host responses contribute to EVD pathophysiology, we performed multi-platform ’omics analysis of peripheral blood mononuclear cells and plasma from EVD patients. Our results indicate that EVD molecular signatures overlap with those of sepsis, imply that pancreatic enzymes contribute to tissue damage in fatal EVD, and suggest that Ebola virus infection may induce aberrant neutrophils whose activity could explain hallmarks of fatal EVD. Moreover, integrated biomarker prediction identified putative biomarkers from different data platforms that differentiated survivors and fatalities early after infection. This work reveals insight into EVD pathogenesis, suggests an effective approach for biomarker identification, and provides an important community resource for further analysis of human EVD severity.

Inhibiting cycloxygenase and ornithine decarboxylase by diclofenac and alpha-difluoromethylornithine blocks cutaneous SCCs by targeting Akt-ERK axis.

Science.gov (United States)

Arumugam, Aadithya; Weng, Zhiping; Talwelkar, Sarang S; Chaudhary, Sandeep C; Kopelovich, Levy; Elmets, Craig A; Afaq, Farrukh; Athar, Mohammad

2013-01-01

Non-melanoma skin cancer (NMSC) is the most common type of skin cancer in Caucasian populations. Its increasing incidence has been a major public health concern. Elevated expressions of ODC and COX-2 are associated with both murine and human NMSCs. Inhibition of these molecular targets singly employing their respective small molecule inhibitors showed limited success. Here, we show that combined blockade of ODC and COX-2 using their potent inhibitors, DFMO and diclofenac respectively abrogates growth of A431 epidermal xenograft tumors in nu/nu mice by more than 90%. The tumor growth inhibition was associated with a diminution in the proliferation and enhancement in apoptosis. The proliferation markers such as PCNA and cyclin D1 were reduced. TUNEL-positive apoptotic cells and cleaved caspase-3 were increased in the residual tumors. These agents also manifested direct target-unrelated effects. Reduced expression of phosphorylated MAPKAP-2, ERK, and Akt (ser(473) & thr(308)) were noticed. The mechanism by which combined inhibition of ODC/COX attenuated tumor growth and invasion involved reduction in EMT. Akt activation by ODC+COX-2 over-expression was the key player in this regard as Akt inhibition manifested effects similar to those observed by the combined inhibition of ODC+COX-2 whereas forced over-expression of Akt resisted against DFMO+diclofenac treatment. These data suggest that ODC+COX-2 over-expression together leads to pathogenesis of aggressive and invasive cutaneous carcinomas by activating Akt signaling pathway, which through augmenting EMT contributes to tumor invasion.

Inhibiting cycloxygenase and ornithine decarboxylase by diclofenac and alpha-difluoromethylornithine blocks cutaneous SCCs by targeting Akt-ERK axis.

Directory of Open Access Journals (Sweden)

Aadithya Arumugam

Full Text Available Non-melanoma skin cancer (NMSC is the most common type of skin cancer in Caucasian populations. Its increasing incidence has been a major public health concern. Elevated expressions of ODC and COX-2 are associated with both murine and human NMSCs. Inhibition of these molecular targets singly employing their respective small molecule inhibitors showed limited success. Here, we show that combined blockade of ODC and COX-2 using their potent inhibitors, DFMO and diclofenac respectively abrogates growth of A431 epidermal xenograft tumors in nu/nu mice by more than 90%. The tumor growth inhibition was associated with a diminution in the proliferation and enhancement in apoptosis. The proliferation markers such as PCNA and cyclin D1 were reduced. TUNEL-positive apoptotic cells and cleaved caspase-3 were increased in the residual tumors. These agents also manifested direct target-unrelated effects. Reduced expression of phosphorylated MAPKAP-2, ERK, and Akt (ser(473 & thr(308 were noticed. The mechanism by which combined inhibition of ODC/COX attenuated tumor growth and invasion involved reduction in EMT. Akt activation by ODC+COX-2 over-expression was the key player in this regard as Akt inhibition manifested effects similar to those observed by the combined inhibition of ODC+COX-2 whereas forced over-expression of Akt resisted against DFMO+diclofenac treatment. These data suggest that ODC+COX-2 over-expression together leads to pathogenesis of aggressive and invasive cutaneous carcinomas by activating Akt signaling pathway, which through augmenting EMT contributes to tumor invasion.

Inhibition of cAMP-activated intestinal chloride secretion by diclofenac: cellular mechanism and potential application in cholera.

Science.gov (United States)

Pongkorpsakol, Pawin; Pathomthongtaweechai, Nutthapoom; Srimanote, Potjanee; Soodvilai, Sunhapas; Chatsudthipong, Varanuj; Muanprasat, Chatchai

2014-09-01

Cyclic AMP-activated intestinal Cl- secretion plays an important role in pathogenesis of cholera. This study aimed to investigate the effect of diclofenac on cAMP-activated Cl- secretion, its underlying mechanisms, and possible application in the treatment of cholera. Diclofenac inhibited cAMP-activated Cl- secretion in human intestinal epithelial (T84) cells with IC50 of ∼ 20 µM. The effect required no cytochrome P450 enzyme-mediated metabolic activation. Interestingly, exposures of T84 cell monolayers to diclofenac, either in apical or basolateral solutions, produced similar degree of inhibitions. Analyses of the apical Cl- current showed that diclofenac reversibly inhibited CFTR Cl- channel activity (IC50 ∼ 10 µM) via mechanisms not involving either changes in intracellular cAMP levels or CFTR channel inactivation by AMP-activated protein kinase and protein phosphatase. Of interest, diclofenac had no effect on Na(+)-K(+) ATPases and Na(+)-K(+)-Cl- cotransporters, but inhibited cAMP-activated basolateral K(+) channels with IC50 of ∼ 3 µM. In addition, diclofenac suppressed Ca(2+)-activated Cl- channels, inwardly rectifying Cl- channels, and Ca(2+)-activated basolateral K(+) channels. Furthermore, diclofenac (up to 200 µM; 24 h of treatment) had no effect on cell viability and barrier function in T84 cells. Importantly, cholera toxin (CT)-induced Cl- secretion across T84 cell monolayers was effectively suppressed by diclofenac. Intraperitoneal administration of diclofenac (30 mg/kg) reduced both CT and Vibrio cholerae-induced intestinal fluid secretion by ∼ 70% without affecting intestinal fluid absorption in mice. Collectively, our results indicate that diclofenac inhibits both cAMP-activated and Ca(2+)-activated Cl- secretion by inhibiting both apical Cl- channels and basolateral K+ channels in intestinal epithelial cells. Diclofenac may be useful in the treatment of cholera and other types of secretory diarrheas resulting from intestinal

Inhibition of cAMP-activated intestinal chloride secretion by diclofenac: cellular mechanism and potential application in cholera.

Directory of Open Access Journals (Sweden)

Pawin Pongkorpsakol

2014-09-01

Full Text Available Cyclic AMP-activated intestinal Cl- secretion plays an important role in pathogenesis of cholera. This study aimed to investigate the effect of diclofenac on cAMP-activated Cl- secretion, its underlying mechanisms, and possible application in the treatment of cholera. Diclofenac inhibited cAMP-activated Cl- secretion in human intestinal epithelial (T84 cells with IC50 of ∼ 20 µM. The effect required no cytochrome P450 enzyme-mediated metabolic activation. Interestingly, exposures of T84 cell monolayers to diclofenac, either in apical or basolateral solutions, produced similar degree of inhibitions. Analyses of the apical Cl- current showed that diclofenac reversibly inhibited CFTR Cl- channel activity (IC50 ∼ 10 µM via mechanisms not involving either changes in intracellular cAMP levels or CFTR channel inactivation by AMP-activated protein kinase and protein phosphatase. Of interest, diclofenac had no effect on Na(+-K(+ ATPases and Na(+-K(+-Cl- cotransporters, but inhibited cAMP-activated basolateral K(+ channels with IC50 of ∼ 3 µM. In addition, diclofenac suppressed Ca(2+-activated Cl- channels, inwardly rectifying Cl- channels, and Ca(2+-activated basolateral K(+ channels. Furthermore, diclofenac (up to 200 µM; 24 h of treatment had no effect on cell viability and barrier function in T84 cells. Importantly, cholera toxin (CT-induced Cl- secretion across T84 cell monolayers was effectively suppressed by diclofenac. Intraperitoneal administration of diclofenac (30 mg/kg reduced both CT and Vibrio cholerae-induced intestinal fluid secretion by ∼ 70% without affecting intestinal fluid absorption in mice. Collectively, our results indicate that diclofenac inhibits both cAMP-activated and Ca(2+-activated Cl- secretion by inhibiting both apical Cl- channels and basolateral K+ channels in intestinal epithelial cells. Diclofenac may be useful in the treatment of cholera and other types of secretory diarrheas resulting from intestinal

Role of phosphoinositide 3-kinase in the pathogenesis of acute pancreatitis.

Science.gov (United States)

Lupia, Enrico; Pigozzi, Luca; Goffi, Alberto; Hirsch, Emilio; Montrucchio, Giuseppe

2014-11-07

A large body of experimental and clinical data supports the notion that inflammation in acute pancreatitis has a crucial role in the pathogenesis of local and systemic damage and is a major determinant of clinical severity. Thus, research has recently focused on molecules that can regulate the inflammatory processes, such as phosphoinositide 3-kinases (PI3Ks), a family of lipid and protein kinases involved in intracellular signal transduction. Studies using genetic ablation or pharmacologic inhibitors of different PI3K isoforms, in particular the class I PI3Kδ and PI3Kγ, have contributed to a greater understanding of the roles of these kinases in the modulation of inflammatory and immune responses. Recent data suggest that PI3Ks are also involved in the pathogenesis of acute pancreatitis. Activation of the PI3K signaling pathway, and in particular of the class IB PI3Kγ isoform, has a significant role in those events which are necessary for the initiation of acute pancreatic injury, namely calcium signaling alteration, trypsinogen activation, and nuclear factor-κB transcription. Moreover, PI3Kγ is instrumental in modulating acinar cell apoptosis, and regulating local neutrophil infiltration and systemic inflammatory responses during the course of experimental acute pancreatitis. The availability of PI3K inhibitors selective for specific isoforms may provide new valuable therapeutic strategies to improve the clinical course of this disease. This article presents a brief summary of PI3K structure and function, and highlights recent advances that implicate PI3Ks in the pathogenesis of acute pancreatitis.

Pathogenic Leptospira: Advances in understanding the molecular pathogenesis and virulence

Science.gov (United States)

Ghazaei, Ciamak

2018-01-01

Leptospirosis is a common zoonotic disease has emerged as a major public health problem, with developing countries bearing disproportionate burdens. Although the diverse range of clinical manifestations of the leptospirosis in humans is widely documented, the mechanisms through which the pathogen causes disease remain undetermined. In addition, leptospirosis is a much-neglected life-threatening disease although it is one of the most important zoonoses occurring in a diverse range of epidemiological distribution. Recent advances in molecular profiling of pathogenic species of the genus Leptospira have improved our understanding of the evolutionary factors that determine virulence and mechanisms that the bacteria employ to survive. However, a major impediment to the formulation of intervention strategies has been the limited understanding of the disease determinants. Consequently, the association of the biological mechanisms to the pathogenesis of Leptospira, as well as the functions of numerous essential virulence factors still remain implicit. This review examines recent advances in genetic screening technologies, the underlying microbiological processes, the virulence factors and associated molecular mechanisms driving pathogenesis of Leptospira species. PMID:29445617

Scleroderma: nomenclature, etiology, pathogenesis, prognosis, and treatments: facts and controversies.

Science.gov (United States)

Fett, Nicole

2013-01-01

Scleroderma refers to a heterogeneous group of autoimmune fibrosing disorders. The nomenclature of scleroderma has changed dramatically in recent years, with morphea (localized scleroderma), limited cutaneous systemic sclerosis, diffuse cutaneous systemic sclerosis, and systemic sclerosis sine scleroderma encompassing the currently accepted disease subtypes. Major advances have been made in the molecular studies of morphea and systemic sclerosis; however, their etiologies and pathogenesis remain incompletely understood. Although morphea and systemic sclerosis demonstrate activation of similar inflammatory and fibrotic pathways, important differences in signaling pathways and gene signatures indicate they are likely biologically distinct processes. Morphea can cause significant morbidity but does not affect mortality, whereas systemic sclerosis has the highest disease-specific mortality of all autoimmune connective tissue diseases. Treatment recommendations for morphea and systemic sclerosis are based on limited data and largely expert opinions. Current collaborative efforts in morphea and systemic sclerosis research will hopefully lead to better understanding of the etiology and pathogenesis of these rare and varied diseases and improved treatment options. Published by Elsevier Inc.

Epigenetics in Medullary Thyroid Cancer: From Pathogenesis to Targeted Therapy.

Science.gov (United States)

Vitale, Giovanni; Dicitore, Alessandra; Messina, Erika; Sciammarella, Concetta; Faggiano, Antongiulio; Colao, Annamaria

2016-01-01

Medullary thyroid carcinoma (MTC) originates from the parafollicular C cells of the thyroid gland. Mutations of the RET proto-oncogene are implicated in the pathogenesis of MTC. Germline activating mutations of this gene have been reported in about 88-98% of familial MTCs, while somatic mutations of RET gene have been detected in about 23-70% of sporadic forms. Although these genetic events are well characterized, much less is known about the role of epigenetic abnormalities in MTC. The present review reports a detailed description of epigenetic abnormalities (DNA methylation, histone modifications and miRNA profile), probably involved in the pathogenesis and progression of MTC. A systematic review was performed using Pubmed and Google patents databases. We report the current understanding of epigenetic patterns in MTC and discuss the potential use of current knowledge in designing novel therapeutic strategies through epigenetic drugs, focusing on recent patents in this field. Taking into account the reversibility of epigenetic alterations and the recent development in this field, epigenetic therapy may emerge for clinical use in the near future for patients with advanced MTC.

MicroRNA involvement in glioblastoma pathogenesis

International Nuclear Information System (INIS)

Novakova, Jana; Slaby, Ondrej; Vyzula, Rostislav; Michalek, Jaroslav

2009-01-01

MicroRNAs are endogenously expressed regulatory noncoding RNAs. Altered expression levels of several microRNAs have been observed in glioblastomas. Functions and direct mRNA targets for these microRNAs have been relatively well studied over the last years. According to these data, it is now evident, that impairment of microRNA regulatory network is one of the key mechanisms in glioblastoma pathogenesis. MicroRNA deregulation is involved in processes such as cell proliferation, apoptosis, cell cycle regulation, invasion, glioma stem cell behavior, and angiogenesis. In this review, we summarize the current knowledge of miRNA functions in glioblastoma with an emphasis on its significance in glioblastoma oncogenic signaling and its potential to serve as a disease biomarker and a novel therapeutic target in oncology.

RLIP76, a glutathione-conjugate transporter, plays a major role in the pathogenesis of metabolic syndrome.

Directory of Open Access Journals (Sweden)

Jyotsana Singhal

Full Text Available PURPOSE: Characteristic hypoglycemia, hypotriglyceridemia, hypocholesterolemia, lower body mass, and fat as well as pronounced insulin-sensitivity of RLIP76⁻/⁻ mice suggested to us the possibility that elevation of RLIP76 in response to stress could itself elicit metabolic syndrome (MSy. Indeed, if it were required for MSy, drugs used to treat MSy should have no effect on RLIP76⁻/⁻ mice. RESEARCH DESIGN AND METHODS: Blood glucose (BG and lipid measurements were performed in RLIP76⁺/⁺ and RLIP76⁻/⁻ mice, using Ascensia Elite Glucometer® for glucose and ID Labs kits for cholesterol and triglycerides assays. The ultimate effectors of gluconeogenesis are the three enzymes: PEPCK, F-1,6-BPase, and G6Pase, and their expression is regulated by PPARγ and AMPK. The activity of these enzymes was tested by protocols standardized by us. Expressions of RLIP76, PPARα, PPARγ, HMGCR, pJNK, pAkt, and AMPK were performed by Western-blot and tissue staining. RESULTS: The concomitant activation of AMPK and PPARγ by inhibiting transport activity of RLIP76, despite inhibited activity of key glucocorticoid-regulated hepatic gluconeogenic enzymes like PEPCK, G6Pase and F-1,6-BP in RLIP76⁻/⁻ mice, is a salient finding of our studies. The decrease in RLIP76 protein expression by rosiglitazone and metformin is associated with an up-regulation of PPARγ and AMPK. CONCLUSIONS/SIGNIFICANCE: All four drugs, rosiglitazone, metformin, gemfibrozil and atorvastatin failed to affect glucose and lipid metabolism in RLIP76⁻/⁻ mice. Studies confirmed a model in which RLIP76 plays a central role in the pathogenesis of MSy and RLIP76 loss causes profound and global alterations of MSy signaling functions. RLIP76 is a novel target for single-molecule therapeutics for metabolic syndrome.

Inhibition of CD147 (Cluster of Differentiation 147) Ameliorates Acute Ischemic Stroke in Mice by Reducing Thromboinflammation.

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Jin, Rong; Xiao, Adam Y; Chen, Rui; Granger, D Neil; Li, Guohong

2017-12-01

Inflammation and thrombosis currently are recognized as critical contributors to the pathogenesis of ischemic stroke. CD147 (cluster of differentiation 147), also known as extracellular matrix metalloproteinase inducer, can function as a key mediator of inflammatory and immune responses. CD147 expression is increased in the brain after cerebral ischemia, but its role in the pathogenesis of ischemic stroke remains unknown. In this study, we show that CD147 acts as a key player in ischemic stroke by driving thrombotic and inflammatory responses. Focal cerebral ischemia was induced in C57BL/6 mice by a 60-minute transient middle cerebral artery occlusion. Animals were treated with anti-CD147 function-blocking antibody (αCD147) or isotype control antibody. Blood-brain barrier permeability, thrombus formation, and microvascular patency were assessed 24 hours after ischemia. Infarct size, neurological deficits, and inflammatory cells invaded in the brain were assessed 72 hours after ischemia. CD147 expression was rapidly increased in ischemic brain endothelium after transient middle cerebral artery occlusion. Inhibition of CD147 reduced infarct size and improved functional outcome on day 3 after transient middle cerebral artery occlusion. The neuroprotective effects were associated with (1) prevented blood-brain barrier damage, (2) decreased intravascular fibrin and platelet deposition, which in turn reduced thrombosis and increased cerebral perfusion, and (3) reduced brain inflammatory cell infiltration. The underlying mechanism may include reduced NF-κB (nuclear factor κB) activation, MMP-9 (matrix metalloproteinase-9) activity, and PAI-1 (plasminogen activator inhibitor-1) expression in brain microvascular endothelial cells. Inhibition of CD147 ameliorates acute ischemic stroke by reducing thromboinflammation. CD147 might represent a novel and promising therapeutic target for ischemic stroke and possibly other thromboinflammatory disorders. © 2017 American Heart

Q fever in pregnant Goats: PAthogenesis and excretion of Coxiella burnetii

NARCIS (Netherlands)

Roest, H.I.J.; Gelderen, van E.; Dinkla, A.; Frangoulidis, D.; Zijderveld, van F.G.; Rebel, J.M.J.; Keulen, van L.J.M.

2012-01-01

Coxiella burnetii is an intracellular bacterial pathogen that causes Q fever. Infected pregnant goats are a major source of human infection. However, the tissue dissemination and excretion pathway of the pathogen in goats are still poorly understood. To better understand Q fever pathogenesis, we

Toll-like receptors in the pathogenesis of human B cell malignancies

NARCIS (Netherlands)

Isaza-Correa, Johana M.; Liang, Zheng; van den Berg, Anke; Diepstra, Arjan; Visser, Lydia

2014-01-01

Toll-like receptors (TLRs) are important players in B-cell activation, maturation and memory and may be involved in the pathogenesis of B-cell lymphomas. Accumulating studies show differential expression in this heterogeneous group of cancers. Stimulation with TLR specific ligands, or agonists of

Understanding Zika virus pathogenesis: an interview with Catherine Spong

OpenAIRE

Spong, Catherine Y.

2016-01-01

A recent outbreak of Zika virus has been linked to fetal abnormalities in pregnant women who have been infected. The scientific community is working toward understanding Zika virus pathogenesis to better manage affected women and children. In an interview with Dr. Catherine Spong, we discuss the aims and challenges of a forthcoming longitudinal study of a cohort of pregnant women in areas of current active Zika virus transmission.

Mesenchymal Stem Cells Inhibit Transmission of α-Synuclein by Modulating Clathrin-Mediated Endocytosis in a Parkinsonian Model

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Se Hee Oh

2016-02-01

Full Text Available Ample evidence suggests that α-synuclein is released from cells and propagated from one area of the brain to others via cell-to-cell transmission. In terms of their prion-like behavior, α-synuclein propagation plays key roles in the pathogenesis and progression of α-synucleinopathies. Using α-synuclein-enriched models, we show that mesenchymal stem cells (MSCs inhibited α-synuclein transmission by blocking the clathrin-mediated endocytosis of extracellular α-synuclein via modulation of the interaction with N-methyl-D-aspartate receptors, which led to a prosurvival effect on cortical and dopaminergic neurons with functional improvement of motor deficits in α-synuclein-enriched models. Furthermore, we identify that galectin-1, a soluble factor derived from MSCs, played an important role in the transmission control of aggregated α-synuclein in these models. The present data indicated that MSCs exert neuroprotective properties through inhibition of extracellular α-synuclein transmission, suggesting that the property of MSCs may act as a disease-modifying therapy in subjects with α-synucleinopathies.

The role of O-GlcNAc signaling in the pathogenesis of diabetic retinopathy.

Science.gov (United States)

Semba, Richard D; Huang, Hu; Lutty, Gerard A; Van Eyk, Jennifer E; Hart, Gerald W

2014-04-01

Diabetic retinopathy is a leading cause of blindness worldwide. Despite laser and surgical treatments, antiangiogenic and other therapies, and strict metabolic control, many patients progress to visual impairment and blindness. New insights are needed into the pathophysiology of diabetic retinopathy in order to develop new methods to improve the detection and treatment of disease and the prevention of blindness. Hyperglycemia and diabetes result in increased flux through the hexosamine biosynthetic pathway, which, in turn, results in increased PTM of Ser/Thr residues of proteins by O-linked β-N-acetylglucosamine (O-GlcNAc). O-GlcNAcylation is involved in regulation of many nuclear and cytoplasmic proteins in a manner similar to protein phosphorylation. Altered O-GlcNAc signaling has been implicated in the pathogenesis of diabetes and may play an important role in the pathogenesis of diabetic retinopathy. The goal of this review is to summarize the biology of the hexosamine biosynthesis pathway and O-GlcNAc signaling, to present the current evidence for the role of O-GlcNAc signaling in diabetes and diabetic retinopathy, and to discuss future directions for research on O-GlcNAc in the pathogenesis of diabetic retinopathy. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Alpha-Amylase Inhibition and Antioxidative Capacity of Some Antidiabetic Plants Used by the Traditional Healers in Southeastern Nigeria

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Sunday O. Oyedemi

2017-01-01

Full Text Available Oxidative stress plays a significant role in the pathogenesis of metabolic syndrome including diabetes mellitus (DM. The inhibition of alpha-amylase is an important therapeutic target in the regulation of postprandial increase of blood glucose in diabetic patients. The present study investigated the alpha-amylase inhibitory and antioxidant potential of selected herbal drugs used in the treatment of DM by the traditional healers in Isiala Mbano and Ikwuano regions of southeastern Nigeria. Antioxidant activity was evaluated in terms of free radical scavenging, reducing power, and total phenolic (TPC and flavonoid content (TFC in consonance with the TLC profiling. The results showed that methanol crude extracts from Anacardium occidentale (AO and Ceiba pentandra (CP recorded higher TPC and TFC, potent free radical scavenging, and efficient reducing power (RP as compared with other plant samples. All the plant extracts exhibited a relative alpha-amylase inhibition apart from Strophanthus hispidus (SH extract with a negative effect. We discovered a mild to weak correlation between alpha-amylase inhibition or antioxidative capacity and the total phenol or flavonoid content. At least in part, the results obtained in this work support the traditional use of certain plant species in the treatment of patients with DM.

Alpha-Amylase Inhibition and Antioxidative Capacity of Some Antidiabetic Plants Used by the Traditional Healers in Southeastern Nigeria

Science.gov (United States)

Oyedemi, Blessing O.; Ijeh, Ifeoma I.; Ohanyerem, Princemartins E.; Aiyegoro, Olayinka A.

2017-01-01

Oxidative stress plays a significant role in the pathogenesis of metabolic syndrome including diabetes mellitus (DM). The inhibition of alpha-amylase is an important therapeutic target in the regulation of postprandial increase of blood glucose in diabetic patients. The present study investigated the alpha-amylase inhibitory and antioxidant potential of selected herbal drugs used in the treatment of DM by the traditional healers in Isiala Mbano and Ikwuano regions of southeastern Nigeria. Antioxidant activity was evaluated in terms of free radical scavenging, reducing power, and total phenolic (TPC) and flavonoid content (TFC) in consonance with the TLC profiling. The results showed that methanol crude extracts from Anacardium occidentale (AO) and Ceiba pentandra (CP) recorded higher TPC and TFC, potent free radical scavenging, and efficient reducing power (RP) as compared with other plant samples. All the plant extracts exhibited a relative alpha-amylase inhibition apart from Strophanthus hispidus (SH) extract with a negative effect. We discovered a mild to weak correlation between alpha-amylase inhibition or antioxidative capacity and the total phenol or flavonoid content. At least in part, the results obtained in this work support the traditional use of certain plant species in the treatment of patients with DM. PMID:28367491

Ibrutinib targets microRNA-21 in multiple myeloma cells by inhibiting NF-κB and STAT3.

Science.gov (United States)

Ma, Jing; Gong, Wei; Liu, Su; Li, Qian; Guo, Mengzheng; Wang, Jinhan; Wang, Suying; Chen, Naiyao; Wang, Yafei; Liu, Qiang; Zhao, Hui

2018-01-01

The oncogenic microRNA-21 contributes to the pathogenesis of multiple myeloma. Ibrutinib (also referred to as PCI-32765), an inhibitor of Bruton's tyrosine kinase, while its effects on multiple myeloma have not been well described. Here, we show that microRNA-21 is an oncogenic marker closely linked with progression of multiple myeloma. Moreover, ibrutinib attenuates microRNA-21 expression in multiple myeloma cells by inhibiting nuclear factor-κB and signal transducer and activator of transcription 3 signaling pathways. Taken together, our results suggest that ibrutinib is a promising potential treatment for multiple myeloma. Further investigation of mechanisms of ibrutinib function in multiple myeloma will be necessary to evaluate its use as a novel multiple myeloma treatment.

Melatonin alleviates inflammasome-induced pyroptosis through inhibiting NF-κB/GSDMD signal in mice adipose tissue.

Science.gov (United States)

Liu, Zhenjiang; Gan, Lu; Xu, Yatao; Luo, Dan; Ren, Qian; Wu, Song; Sun, Chao

2017-08-01

Pyroptosis is a proinflammatory form of cell death that is associated with pathogenesis of many chronic inflammatory diseases. Melatonin is substantially reported to possess anti-inflammatory properties by inhibiting inflammasome activation. However, the effects of melatonin on inflammasome-induced pyroptosis in adipocytes remain elusive. Here, we demonstrated that melatonin alleviated lipopolysaccharides (LPS)-induced inflammation and NLRP3 inflammasome formation in mice adipose tissue. The NLRP3 inflammasome-mediated pyroptosis was also inhibited by melatonin in adipocytes. Further analysis revealed that gasdermin D (GSDMD), the key executioner of pyroptosis, was the target for melatonin inhibition of adipocyte pyroptosis. Importantly, we determined that nuclear factor κB (NF-κB) signal was required for the GSDMD-mediated pyroptosis in adipocytes. We also confirmed that melatonin alleviated adipocyte pyroptosis by transcriptional suppression of GSDMD. Moreover, GSDMD physically interacted with interferon regulatory factor 7 (IRF7) and subsequently formed a complex to promote adipocyte pyroptosis. Melatonin also attenuated NLRP3 inflammasome activation and pyroptosis, which was induced by LPS or obesity. In summary, our results demonstrate that melatonin alleviates inflammasome-induced pyroptosis by blocking NF-κB/GSDMD signal in mice adipose tissue. Our data reveal a novel function of melatonin on adipocyte pyroptosis, suggesting a new potential therapy for melatonin to prevent and treat obesity caused systemic inflammatory response. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

MDS: Recent progress in molecular pathogenesis and clinical aspects.

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Harada, Hironori

2017-01-01

Myelodysplastic syndromes (MDS) are defined as hematopoietic stem cell disorders caused by various gene abnormalities. Recent analysis using next generation sequencing has provided great progress in identifying relationships between gene mutations and clinical phenotypes of MDS. It is estimated that one or more gene mutations occur in greater than 90% of MDS patients. More than 50 gene mutations affecting RNA splicing machinery, DNA methylation, histone modifications, transcription factors, signal transduction proteins, and components of the cohesion complex participate in the pathogenesis of MDS. The sequential accumulation of additional cooperating mutations drives disease evolution from clonal hematopoiesis of indeterminate potential (CHIP) to symptomatic MDS and from MDS to acute myelogenous leukemia (AML). Mutations in RNA splicing and DNA methylation occur early and are considered founding mutations, whereas others that occur later are regarded as subclonal mutations. RUNX1 mutations are more likely to be subclonal; however, they apparently play a pivotal role in familial MDS. In addition, large alterations of chromosomes are involved in the pathogenesis of MDS. 5q- syndrome, which leads to haploinsufficiency of the located genes, has consistent clinical features. Understanding gene abnormalities of MDS patients can provide clinical information, including diagnosis, prognostic score, and prediction of response to therapy.

The role of endotoxin in the pathogenesis of acute bovine laminitis.

Science.gov (United States)

Boosman, R; Mutsaers, C W; Klarenbeek, A

1991-07-01

To study the possible role of endotoxin in the pathogenesis of bovine laminitis, local and systemic injections of endotoxin (E. coli 0111 B4) with different doses were given to three groups of four cows each. Clinical and haematologic parameters indicated an acute-phase response, including positive plasma ethanol gelation (soluble fibrin), the occurrence of fibrin degradation products and decreased thrombocyte counts. Local Shwartzman reactions were not evoked. Clinical examination of the claws and the gait of the animals revealed no signs of laminitis. However, on histopathological examination of the claw corium signs of laminitis such as vacuolisation of the Stratum basale, lymphocyte and leucocyte infiltration and thrombosis were found. These results indicate that endotoxin indeed may be involved in the pathogenesis of laminitis. For the development of a clinical acute laminitis model in cattle either another dosage, other toxins or factors in addition to the endotoxin used in this experiment are needed.

Physiology and pathogenesis of gastroesophageal reflux disease.

Science.gov (United States)

Mikami, Dean J; Murayama, Kenric M

2015-06-01

Gastroesophageal reflux disease (GERD) is one of the most common problems treated by primary care physicians. Almost 20% of the population in the United States experiences occasional regurgitation, heartburn, or retrosternal pain because of GERD. Reflux disease is complex, and the physiology and pathogenesis are still incompletely understood. However, abnormalities of any one or a combination of the three physiologic processes, namely, esophageal motility, lower esophageal sphincter function, and gastric motility or emptying, can lead to GERD. There are many diagnostic and therapeutic approaches to GERD today, but more studies are needed to better understand this complex disease process. Copyright © 2015 Elsevier Inc. All rights reserved.

Atomic Force Microscopy Provides New Mechanistic Insights into the Pathogenesis of Pemphigus

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Franziska Vielmuth

2018-03-01

Full Text Available Autoantibodies binding to the extracellular domains of desmoglein (Dsg 3 and 1 are critical in the pathogenesis of pemphigus by mechanisms leading to impaired function of desmosomes and blister formation in the epidermis and mucous membranes. Desmosomes are highly organized protein complexes which provide strong intercellular adhesion. Desmosomal cadherins such as Dsgs, proteins of the cadherin superfamily which interact via their extracellular domains in Ca2+-dependent manner, are the transmembrane adhesion molecules clustered within desmosomes. Investigations on pemphigus cover a wide range of experimental approaches including biophysical methods. Especially atomic force microscopy (AFM has recently been applied increasingly because it allows the analysis of native materials such as cultured cells and tissues under near-physiological conditions. AFM provides information about the mechanical properties of the sample together with detailed interaction analyses of adhesion molecules. With AFM, it was recently demonstrated that autoantibodies directly inhibit Dsg interactions on the surface of living keratinocytes, a phenomenon which has long been considered the main mechanism causing loss of cell cohesion in pemphigus. In addition, AFM allows to study how signaling pathways altered in pemphigus control binding properties of Dsgs. More general, AFM and other biophysical studies recently revealed the importance of keratin filaments for regulation of Dsg binding and keratinocyte mechanical properties. In this mini-review, we reevaluate AFM studies in pemphigus and keratinocyte research, recapitulate what is known about the interaction mechanisms of desmosomal cadherins and discuss the advantages and limitations of AFM in these regards.

Fetal/Neonatal Alloimmune Thrombocytopenia: Pathogenesis, Diagnostics and Prevention.

Science.gov (United States)

Brojer, Ewa; Husebekk, Anne; Dębska, Marzena; Uhrynowska, Małgorzata; Guz, Katarzyna; Orzińska, Agnieszka; Dębski, Romuald; Maślanka, Krystyna

2016-08-01

Fetal/neonatal alloimmune thrombocytopenia (FNAIT) is a relatively rare condition (1/1000-1/2000) that was granted orphan status by the European Medicines Agency in 2011. Clinical consequences of FNAIT, however, may be severe. A thrombocytopenic fetus or new-born is at risk of intracranial hemorrhage that may result in lifelong disability or death. Preventing such bleeding is thus vital and requires a solution. Anti-HPA1a antibodies are the most frequent cause of FNAIT in Caucasians. Its pathogenesis is similar to hemolytic disease of the newborn (HDN) due to anti-RhD antibodies, but is characterized by platelet destruction and is more often observed in the first pregnancy. In 75 % of these women, alloimmunization by HPA-1a antigens, however, occurs at delivery, which enables development of antibody-mediated immune suppression to prevent maternal immunization. As for HDN, the recurrence rate of FNAIT is high. For advancing diagnostic efforts and treatment, it is thereby crucial to understand the pathogenesis of FNAIT, including cellular immunity involvement. This review presents the current knowledge on FNAIT. Also described is a program for HPA-1a screening in identifying HPA-1a negative pregnant women at risk of immunization. This program is now performed at the Institute of Hematology and Transfusion Medicine in cooperation with the Department of Obstetrics and Gynecology of the Medical Centre of Postgraduate Education in Warsaw as well as the UiT The Arctic University of Norway.

Hand osteoarthritis: diagnosis, pathogenesis, treatment

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R. M. Balabanova

2018-01-01

Full Text Available Due to the development of synovitis, early-stage hand osteoarthritis (HOA mimics hand joint injury in rheumatoid arthritis (RA. However, the topography of synovitis is diverse in these diseases:  distal interphalangeal and thumb joints are involved in the process in HOA. In the latter, tests are negative for immunological markers  (anti-cyclic citrullinated peptide antibodies, which is typical of RA.  The differences between HOA and RA are prominent, as evidenced  by hand X-rays and magnetic resonance imaging. Investigations  suggest that cytokine profile imbalance is implicated in the  pathogenesis of osteoarthritis, which brings it closer to RA. However, therapy for HOA has not been practically developed; there are only a few works on the use of disease-modifying antirheumatic drugs and  biological agents in these patients. It is necessary to work out Russian guidelines for the treatment of HOA.

[The evolution of related names of Bi syndrome and the theory of etiology and pathogenesis].

Science.gov (United States)

Dai, Jian-hua; Shi, Ying-jie; Yin, Hai-bo; Du, Hui

2009-07-01

In the Traditional Chinese medical literature of ancient times, Bi referred to the pathogenesis, or the symptoms as well as the name of the disease. As the name of a disease, Bi has the different meanings of broad and narrow., joint-running, joint-running wind, white tiger joint-running, gout etc. referring to the narrow meaning of Bi disease. The theory of etiology and pathogenesis of the narrow meaning of Bi disease developed from damp-impediment, wind-cold-damp impediment to damp-hot impediment, stasis-hot impediment, which reflected the constant deepening of cognition.

Zebrafish Functional Genetics Approach to the Pathogenesis of Well-Differentiated Liposarcoma

Science.gov (United States)

2015-12-01

Roderick JE, LaBelle JL, Bird G, Mathieu R, Bodaar K, Colon D, Pyati U, Stevenson KE, Qi J, Harris M, Silverman LB, Sallan SE, Bradner JL, Neuberg DS...pathogenesis of high-risk T-cell acute lymphoblastic leukemia. Our approach combines human cancer genomics with functional genetics, biochemistry and

How can macroscopically normal peritoneum contribute to the pathogenesis of endometriosis?

Science.gov (United States)

Fassbender, Amelie; Overbergh, Lut; Verdrengh, Eefje; Kyama, Cleophas M; Vodolazakaia, Alexandra; Bokor, Attila; Meuleman, Christel; Peeraer, Karen; Tomassetti, Carla; Waelkens, Etienne; Mathieu, Chantal; D'Hooghe, Thomas

2011-09-01

This study indicates that the immunobiology of macroscopically normal peritoneum is relevant to understand the pathogenesis of endometriosis. Peritoneal interleukin 6, interleukin 12, and ferritin were differentially expressed in women with and without endometriosis. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Functional modeling of the craniospinal system for in-vitro parameter studies on the pathogenesis of NPH

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Benninghaus Anne

2017-09-01

Full Text Available Normal Pressure Hydrocephalus (NPH has become a common disease in the elderly coming along with typical symptoms of dementia, gait ataxia and urinary incontinence, which make the differential diagnosis with other forms of dementia difficult. Furthermore the pathogenesis of NPH is still not understood. About 10% of all demented patients might be suffering from NPH [1]. Many hypotheses suggest that modified biomechanical boundary conditions affect the craniospinal dynamics inducing the pathogenesis of NPH. We present a novel approach for an in-vitro model of the craniospinal system to investigate important hydrodynamic influences on the system such as (dynamic compliance of the vascular system and especially the spinal subarachnoid space (SAS as well as reabsorption and hydrostatics. The experimental set-up enables the individual adjustment of relevant parameters for sensitivity analyses regarding the impact of resulting CSF dynamics on the pathogenesis of NPH.

Overexpression of Mitofusin 2 inhibited oxidized low-density lipoprotein induced vascular smooth muscle cell proliferation and reduced atherosclerotic lesion formation in rabbit

International Nuclear Information System (INIS)

Guo Yanhong; Chen Kuanghueih; Gao Wei; Li Qian; Chen Li; Wang Guisong; Tang Jian

2007-01-01

Our previous studies have implies that Mitofusin 2 (Mfn2), which was progressively reduced in arteries from ApoE -/- mice during the development of atherosclerosis, may take part in pathogenesis of atherosclerosis. In this study, we found that overexpression of Mfn2 inhibited oxidized low-density lipoprotein or serum induced vascular smooth muscle cell proliferation by down-regulation of Akt and ERK phosphorylation. Then we investigated the in vivo role of Mfn2 on the development of atherosclerosis in rabbits using adenovirus expressing Mitofusin 2 gene (AdMfn2). By morphometric analysis we found overexpression of Mfn2 inhibited atherosclerotic lesion formation and intima/media ratio by 66.7% and 74.6%, respectively, compared with control group. These results suggest that local Mfn2 treatment suppresses the development of atherosclerosis in vivo in part by attenuating the smooth muscle cell proliferation induced by lipid deposition and vascular injury

Pathogenesis of Mycobacterium bovis Infection: the Badger Model As a Paradigm for Understanding Tuberculosis in Animals

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Eamonn Gormley

2018-01-01

Full Text Available Tuberculosis in animals is caused principally by infection with Mycobacterium bovis and the potential for transmission of infection to humans is often the fundamental driver for surveillance of disease in livestock and wild animals. However, with such a vast array of species susceptible to infection, it is often extremely difficult to gain a detailed understanding of the pathogenesis of infection––a key component of the epidemiology in all affected species. This is important because the development of disease control strategies in animals is determined chiefly by an understanding of the epidemiology of the disease. The most revealing data from which to formulate theories on pathogenesis are that observed in susceptible hosts infected by natural transmission. These data are gathered from detailed studies of the distribution of gross and histological lesions, and the presence and distribution of infection as determined by highly sensitive bacteriology procedures. The information can also be used to establish the baseline for evaluating experimental model systems. The European badger (Meles meles is one of a very small number of wild animal hosts where detailed knowledge of the pathogenesis of M. bovis infection has been generated from observations in natural-infected animals. By drawing parallels from other animal species, an experimental badger infection model has also been established where infection of the lower respiratory tract mimics infection and the disease observed in natural-infected badgers. This has facilitated the development of diagnostic tests and testing of vaccines that have the potential to control the disease in badgers. In this review, we highlight the fundamental principles of how detailed knowledge of pathogenesis can be used to evaluate specific intervention strategies, and how the badger model may be a paradigm for understanding pathogenesis of tuberculosis in any affected wild animal species.

Pathogenesis and symptomatics of the acute radiation syndrome

International Nuclear Information System (INIS)

Fliedner, T.M.; Haen, M.; Carbonell, F.

1980-01-01

The pathogenesis and symptomatics of the acute radiation syndrome are discussed. Diagnosis and therapy would be impossible without detailed knowledge in these fields. The concept of acute radiation syndrome is explained, and a pathophysiological analysis of the various forms of radiation syndrome - haematological, intestinal and affecting the central nervous system is attempted. The developments in the diagnosis and therapy of acute radiation syndrome since its first description - 35 years ago - are reviewed. Today, whole-body doses of 100 rd and more can be treated by radiotherapy. (orig./MG) [de

Combined Effects of Feedforward Inhibition and Excitation in Thalamocortical Circuit on the Transitions of Epileptic Seizures

Science.gov (United States)

Fan, Denggui; Duan, Lixia; Wang, Qian; Luan, Guoming

2017-01-01

The mechanisms underlying electrophysiologically observed two-way transitions between absence and tonic-clonic epileptic seizures in cerebral cortex remain unknown. The interplay within thalamocortical network is believed to give rise to these epileptic multiple modes of activity and transitions between them. In particular, it is thought that in some areas of cortex there exists feedforward inhibition from specific relay nucleus of thalamus (TC) to inhibitory neuronal population (IN) which has even more stronger functions on cortical activities than the known feedforward excitation from TC to excitatory neuronal population (EX). Inspired by this, we proposed a modified computational model by introducing feedforward inhibitory connectivity within thalamocortical circuit, to systematically investigate the combined effects of feedforward inhibition and excitation on transitions of epileptic seizures. We first found that the feedforward excitation can induce the transition from tonic oscillation to spike and wave discharges (SWD) in cortex, i.e., the epileptic tonic-absence seizures, with the fixed weak feedforward inhibition. Thereinto, the phase of absence seizures corresponding to strong feedforward excitation can be further transformed into the clonic oscillations with the increasing of feedforward inhibition, representing the epileptic absence-clonic seizures. We also observed the other fascinating dynamical states, such as periodic 2/3/4-spike and wave discharges, reversed SWD and clonic oscillations, as well as saturated firings. More importantly, we can identify the stable parameter regions representing the tonic-clonic oscillations and SWD discharges of epileptic seizures on the 2-D plane composed of feedforward inhibition and excitation, where the physiologically plausible transition pathways between tonic-clonic and absence seizures can be figured out. These results indicate the functional role of feedforward pathways in controlling epileptic seizures and

Combined Effects of Feedforward Inhibition and Excitation in Thalamocortical Circuit on the Transitions of Epileptic Seizures

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Denggui Fan

2017-07-01

Full Text Available The mechanisms underlying electrophysiologically observed two-way transitions between absence and tonic-clonic epileptic seizures in cerebral cortex remain unknown. The interplay within thalamocortical network is believed to give rise to these epileptic multiple modes of activity and transitions between them. In particular, it is thought that in some areas of cortex there exists feedforward inhibition from specific relay nucleus of thalamus (TC to inhibitory neuronal population (IN which has even more stronger functions on cortical activities than the known feedforward excitation from TC to excitatory neuronal population (EX. Inspired by this, we proposed a modified computational model by introducing feedforward inhibitory connectivity within thalamocortical circuit, to systematically investigate the combined effects of feedforward inhibition and excitation on transitions of epileptic seizures. We first found that the feedforward excitation can induce the transition from tonic oscillation to spike and wave discharges (SWD in cortex, i.e., the epileptic tonic-absence seizures, with the fixed weak feedforward inhibition. Thereinto, the phase of absence seizures corresponding to strong feedforward excitation can be further transformed into the clonic oscillations with the increasing of feedforward inhibition, representing the epileptic absence-clonic seizures. We also observed the other fascinating dynamical states, such as periodic 2/3/4-spike and wave discharges, reversed SWD and clonic oscillations, as well as saturated firings. More importantly, we can identify the stable parameter regions representing the tonic-clonic oscillations and SWD discharges of epileptic seizures on the 2-D plane composed of feedforward inhibition and excitation, where the physiologically plausible transition pathways between tonic-clonic and absence seizures can be figured out. These results indicate the functional role of feedforward pathways in controlling epileptic

Porcine Circovirus-Like Virus P1 Inhibits Wnt Signaling Pathway in Vivo and in Vitro

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Xuejiao Zhu

2018-03-01

Full Text Available Porcine circovirus-like virus P1 is an important pathogen of the current pig industry, the infection mechanism is not entirely clear. Wnt signaling pathway plays an important role in the growth of young animals and infection of some viruses. This study was designed to demonstrate the effects of P1 infection on the Wnt signaling pathway. In vivo experiments, we demonstrated the down-regulatory effects of P1 infection in piglets and mice on the downstream components expression levels of Wnt signaling pathway, and the effects of Wnt signaling pathway activation on the pathogenesis of P1. In vitro studies, we found P1 infection down-regulated protein level of β-catenin and mRNA level of mmp2, prevented the β-catenin from entering into nucleus, abolished the TCF/LEF promoter activity, proved that P1 could inhibit the activation of Wnt signaling pathway in vitro. Finally, we found that VP1 of P1 virus also had the inhibitory effects on Wnt signaling pathway in vitro, elucidated the mechanism of P1’s inhibitory effects on the Wnt signaling pathway and offered the possibility that the suppression of Wnt signaling pathway was involved in the post-weaning multisystemic wasting syndrome (PMWS, laying a foundation for elucidating the pathogenesis of P1.

Origin and pathogenesis of antiphospholipid antibodies

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C.M. Celli

1998-06-01

Full Text Available Antiphospholipid antibodies (aPL are a heterogeneous group of antibodies that are detected in the serum of patients with a variety of conditions, including autoimmune (systemic lupus erythematosus, infectious (syphilis, AIDS and lymphoproliferative disorders (paraproteinemia, myeloma, lymphocytic leukemias. Thrombosis, thrombocytopenia, recurrent fetal loss and other clinical complications are currently associated with a subgroup of aPL designating the antiphospholipid syndrome. In contrast, aPL from patients with infectious disorders are not associated with any clinical manifestation. These findings led to increased interest in the origin and pathogenesis of aPL. Here we present the clinical features of the antiphospholipid syndrome and review the origin of aPL, the characteristics of experimentally induced aPL and their historical background. Within this context, we discuss the most probable pathogenic mechanisms induced by these antibodies.

Renal glucose handling in diabetes and sodium glucose cotransporter 2 inhibition

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Resham Raj Poudel

2013-01-01

Full Text Available The kidneys play a major role in glucose homeostasis through its utilization, gluconeogenesis, and reabsorption via sodium glucose cotransporters (SGLTs. The defective renal glucose handling from upregulation of SGLTs, mainly the SGLT2, plays a fundamental role in the pathogenesis of type 2 diabetes mellitus. Genetic mutations in a SGLT2 isoform that results in benign renal glycosuria, as well as clinical studies with SGLT2 inhibitors in type 2 diabetes support the potential of this approach. These studies indicate that inducing glycosuria by suppressing SGLT2 can reduce plasma glucose and A1c levels, as well as decrease weight, resulting in improved β-cell function and enhanced insulin sensitivity in liver and muscle. Because the mechanism of SGLT2 inhibition is independent of insulin secretion and sensitivity, these agents can be combined with other antidiabetic agents, including exogenous insulin. This class represents a novel therapeutic approach with potential for the treatment of both type 2 and type 1 diabetes.

PATHOGENESIS OF OPTIC DISC EDEMA IN RAISED INTRACRANIAL PRESSURE

Science.gov (United States)

Hayreh, Sohan Singh

2015-01-01

Optic disc edema in raised intracranial pressure was first described in 1853. Ever since, there has been a plethora of controversial hypotheses to explain its pathogenesis. I have explored the subject comprehensively by doing basic, experimental and clinical studies. My objective was to investigate the fundamentals of the subject, to test the validity of the previous theories, and finally, based on all these studies, to find a logical explanation for the pathogenesis. My studies included the following issues pertinent to the pathogenesis of optic disc edema in raised intracranial pressure: the anatomy and blood supply of the optic nerve, the roles of the sheath of the optic nerve, of the centripetal flow of fluids along the optic nerve, of compression of the central retinal vein, and of acute intracranial hypertension and its associated effects. I found that, contrary to some previous claims, an acute rise of intracranial pressure was not quickly followed by production of optic disc edema. Then, in rhesus monkeys, I produced experimentally chronic intracranial hypertension by slowly increasing in size space-occupying lesions, in different parts of the brain. Those produced raised cerebrospinal fluid pressure (CSFP) and optic disc edema, identical to those seen in patients with elevated CSFP. Having achieved that, I investigated various aspects of optic disc edema by ophthalmoscopy, stereoscopic color fundus photography and fluorescein fundus angiography, and light microscopic, electron microscopic, horseradish peroxidase and axoplasmic transport studies, and evaluated the effect of opening the sheath of the optic nerve on the optic disc edema. This latter study showed that opening the sheath resulted in resolution of optic disc edema on the side of the sheath fenestration, in spite of high intracranial CSFP, proving that a rise of CSFP in the sheath was the essential pre-requisite for the development of optic disc edema. I also investigated optic disc edema with

Dysregulated microRNAs in neural system: Implication in pathogenesis and biomarker development in Parkinson's disease.

Science.gov (United States)

Lu, Jiangkun; Xu, Yan; Quan, Zhenzhen; Chen, Zixuan; Sun, Zhenzhen; Qing, Hong

2017-12-04

Parkinson's disease is a debilitating neurodegenerative movement disorder, characterized by the progressive and selective loss of dopaminergic neurons located in the substantia nigra, leading to clinical motor symptoms. The factors involved in PD are rather multifaceted. There are many cellular pathways contributing to its neuro-pathogenesis, which include abnormal protein aggregation, impaired ubiquitin proteasome system, autophagy, and neuroinflammation. However, despite years of investigation, still little is known about early events in the molecular pathogenesis. MicroRNAs are small non-coding RNAs that can regulate post-transcriptional expression of mRNAs. Since they somewhat modulate many mRNA targets simultaneously, many cellular pathways may be affected by one individual miRNA. Moreover, miRNAs can stably circulate in cerebrospinal fluid and blood, and their expression pattern can reflect the molecular pathophysiology, thus making them promising biomarkers in PD diagnosis and prognosis. In this review, we will review the recent progress on miRNA's mechanism in PD pathogenesis and discuss the possibilities of miRNAs as PD molecular biomarkers. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Anxiety and retrieval inhibition: support for an enhanced inhibition account.

Science.gov (United States)

Nuñez, Mia; Gregory, Josh; Zinbarg, Richard E

2017-02-01

Retrieval inhibition of negative associations is important for exposure therapy for anxiety, but the relationship between memory inhibition and anxiety is not well understood-anxiety could either be associated with enhanced or deficient inhibition. The present study tested these two competing hypotheses by measuring retrieval inhibition of negative stimuli by related neutral stimuli. Non-clinically anxious undergraduates completed measures of trait and state anxiety and completed a retrieval induced forgetting task. Adaptive forgetting varied with state anxiety. Low levels of state anxiety were associated with no evidence for retrieval inhibition for either threatening or non-threatening categories. Participants in the middle tertile of state anxiety scores exhibited retrieval inhibition for non-threatening categories but not for threatening categories. Participants in the highest tertile of state anxiety, however, exhibited retrieval inhibition for both threatening and non-threatening categories with the magnitude of retrieval inhibition being greater for threatening than non-threatening categories. The data are in line with the avoidance aspect of the vigilance-avoidance theory of anxiety and inhibition. Implications for cognitive behavioural therapy practices are discussed.

Huperzine A inhibits CCL2 production in experimental autoimmune encephalomyelitis mice and in cultured astrocyte.

Science.gov (United States)

Tian, G X; Zhu, X Q; Chen, Y; Wu, G C; Wang, J

2013-01-01

The active role of chemokines and inflammatory cytokines in the central nervous system (CNS) during the pathogenesis of experimental autoimmune encephalomyelitis (EAE) has been clearly established. Recent studies from our laboratory reported that Huperzine A (HupA) can attenuate the disease process in EAE by the inhibition of inflammation, demyelination, and axonal injury in the spinal cord as well as encephalomyelitic T-cell proliferation. In this study, the effects of low dose HupA on CCL2, TNF-alpha, IL-6, and IL-1beta expression were evaluated in EAE. The effect of HupA on lipopolysachharide (LPS)-induced inflammatory molecule secretion was investigated in cultured-astrocytes in vitro. In MOG35-55-induced EAE mice, intraperitoneal injections of HupA (0.1 mg/kg•d−1) significantly suppressed the expression of CCL2, IL-6, TNF-alpha, and IL-1beta in the spinal cord. HupA also repressed LPS-induced CCL2 production, but with little influence on pro-inflammatory cytokines in primary cultured astrocytes. The inhibition effect of HupA on CCL2 is PPARgamma-dependent and nicotine receptor-independent. Conditioned culture media from HupA-treated astrocyte decreased PBMC migration in vitro. Collectively, these results suggest that HupA can ameliorate EAE by inhibiting CCL2 production in astrocyte, which may consequently decrease inflammatory cell infiltration in the spinal cord. HupA may have a potential therapeutic value for the treatment of MS and other neuroinflammatory diseases.

Membranous nephropathy: A review on the pathogenesis, diagnosis, and treatment

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Wei Ling Lai

2015-02-01

Full Text Available In adults, membranous nephropathy (MN is a major cause of nephrotic syndrome. However, the etiology of approximately 75% of MN cases is idiopathic. Secondary causes of MN are autoimmune diseases, infection, drugs, and malignancy. The pathogenesis of MN involves formation of immune complex in subepithelial sites, but the definite mechanism is still unknown. There are three hypotheses about the formation of immune complex, including preformed immune complex, in situ immune-complex formation, and autoantibody against podocyte membrane antigen. The formation of immune complex initiates complement activation, which subsequently leads to glomerular damage. Recently, the antiphospholipase A2 receptor antibody was found to be associated with idiopathic MN. This finding may be useful in the diagnosis and prognosis of MN. The current treatment includes best supportive care, which consists of the use of angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers, lipid-lowering agents, and optimal control of blood pressure. Immunosuppressive agents should be used for patients who suffer from refractory proteinuria or complications associated with nephrotic syndrome. Existing evidence supports the use of a combination of steroid and alkylating agents. This article reviews the epidemiology, pathogenesis, diagnosis, and the treatment of MN.

Molecular Pathogenesis of Liver Steatosis Induced by Hepatitis C Virus

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Cheng Jun

2012-09-01

Full Text Available Liver steatosis is a pathological hallmark in patients with chronic hepatitis C (CHC. Increased lipid uptake, decreased lipid secretion, increased lipid synthesis and decreased lipid degradation are all involved in pathogenesis of steatosis induced by hepatitic C virus (HCV infection. Level of low density lipoprotein receptor (LDL-R and activity of peroxisome proliferator-activated receptor (PPAR α is related to liver uptake of lipid from circulation, and affected by HCV. Secretion via microsomal triglyceride transfer protein (MTTP, and formation of very low density lipoprotein (VLDL have been hampered by HCV infection. Up-regulation of lipid synthesis related genes, such as sterol regulatory element-binding protein (SREBP-1, SREBP-2, SREBP-1c, fatty acid synthase (FASN, HMG CoA reductase (HMGCR, liver X receptor (LXR, acetyl-CoA carboxylase 1 (ACC1, hepatic CB (1 receptors, retinoid X receptor (RXR α, were the main stay of liver steatosis pathogenesis. Degradation of lipid in liver is decreased in patients with CHC. There is strong evidence that heterogeneity of HCV core genes of different genotypes affect their effects of liver steatosis induction. A mechanism in which steatosis is involved in HCV life cycle is emerging.

Association between pretreatment Glasgow prognostic score and gastric cancer survival and clinicopathological features: a meta-analysis

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Zhang CX

2016-06-01

Full Text Available Chun-Xiao Zhang,* Shu-Yi Wang,* Shuang-Qian Chen, Shuai-Long Yang, Lu Wan, Bin Xiong Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan, Hubei, People’s Republic of China *These authors contributed equally to this work Background: Glasgow prognostic score (GPS is widely known as a systemic inflammatory-based marker. The relationship between pretreatment GPS and gastric cancer (GC survival and clinicopathological features remains controversial. The aim of the study was to conduct a meta-analysis of published studies to evaluate the association between pretreatment GPS and survival and clinicopathological features in GC patients. Methods: We searched PubMed, Embase, MEDLINE, and BioMed databases for relevant studies. Combined analyses were used to assess the association between pretreatment GPS and overall survival, disease-free survival, and clinicopathological parameters by Stata Version 12.0. Results: A total of 14 studies were included in this meta-analysis, including 5,579 GC patients. The results indicated that pretreatment high GPS (HGPS predicted poor overall survival (hazard ratio =1.51, 95% CI: 1.37–1.66, P<0.01 and disease-free survival (hazard ratio =1.45, 95% CI: 1.26–1.68, P<0.01 in GC patients. Pretreatment HGPS was also significantly associated with advanced tumor–node–metastasis stage (odds ratio [OR] =3.09, 95% CI: 2.11–4.53, P<0.01, lymph node metastasis (OR =4.60, 95% CI: 3.23–6.56, P<0.01, lymphatic invasion (OR =3.04, 95% CI: 2.00–4.62, P<0.01, and venous invasion (OR =3.56, 95% CI: 1.81–6.99, P<0.01. Conclusion: Our meta-analysis indicated that pretreatment HGPS could be a predicative factor of poor survival outcome and clinicopathological features for GC patients. Keywords: Glasgow prognostic score, gastric cancer, survival, clinicopathological feature

Differential histopathologic parameters in colorectal cancer liver metastases resected after triplets plus bevacizumab or cetuximab: a pooled analysis of five prospective trials.

Science.gov (United States)

Cremolini, Chiara; Milione, Massimo; Marmorino, Federica; Morano, Federica; Zucchelli, Gemma; Mennitto, Alessia; Prisciandaro, Michele; Lonardi, Sara; Pellegrinelli, Alessio; Rossini, Daniele; Bergamo, Francesca; Aprile, Giuseppe; Urbani, Lucio; Morelli, Luca; Schirripa, Marta; Cardellino, Giovanni Gerardo; Fassan, Matteo; Fontanini, Gabriella; de Braud, Filippo; Mazzaferro, Vincenzo; Falcone, Alfredo; Pietrantonio, Filippo

2018-04-01

Many factors, including histopathologic parameters, seem to influence the prognosis of patients undergoing resection of colorectal cancer liver metastases (CRCLM), although their relative weight is unclear. Histopathologic growth patterns (HGPs) of CRCLM may affect sensitivity to antiangiogenics. We aimed at evaluating differences in histopathologic parameters of response according to the use of bevacizumab or cetuximab as first-line targeted agents, and at exploring the prognostic and predictive role of HGPs. We performed a comprehensive histopathologic characterisation of CRCLM from 159 patients who underwent secondary resection, after receiving triplets FOLFOXIRI (folinic acid, 5-fluorouracil, oxaliplatin, and irinotecan) or COI (capecitabine, oxaliplatin, and irinotecan) plus bevacizumab (N = 103) vs cetuximab (N = 56) in five first-line no-profit clinical trials. Both major histopathologic response (tumour regression grade TRG1-2, 32 vs 14%, p = 0.013) and infarct-like necrosis (80 vs 64%, p = 0.035) were significantly higher in the bevacizumab than in the cetuximab group. Achieving major response positively affected relapse-free survival (RFS) (p = 0.012) and overall survival (OS) (p = 0.045), also in multivariable models (RFS, p = 0.008; OS, p = 0.033). In the desmoplastic HGP (N = 28), a higher percentage of major response was reported (57 vs 17% in pushing and 22% in replacement HGP, p < 0.001) and an unsignificant advantage from cetuximab vs bevacizumab was evident in RFS (p = 0.116). In the pushing HGP (N = 66), a significant benefit from bevacizumab vs cetuximab (p = 0.017) was observed. No difference was described in the replacement HGP (N = 65, p = 0.615). The histopathologic response is the only independent determinant of survival in patients resected after triplets plus a biologic. When associated with triplet chemotherapy, bevacizumab induces a higher histopathologic response rate than

IL-1 inhibition in systemic juvenile idiopathic arthritis

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Gabriella Giancane

2016-12-01

Full Text Available Systemic juvenile idiopathic arthritis (sJIA is the form of childhood arthritis whose treatment is most challenging. The demonstration of the prominent involvement of interleukin (IL-1 in disease pathogenesis has provided the rationale for the treatment with biologic medications that antagonize this cytokine. The three IL-1 blockers that have been tested so far (anakinra, canakinumab and rilonacept have all been proven effective and safe, although only canakinumab is currently approved for use in sJIA. The studies on IL-1 inhibition in sJIA published in the past few years suggest that children with fewer affected joints, higher neutrophil count, younger age at disease onset, shorter disease duration, or, possibly, higher ferritin level may respond better to anti-IL-1 treatment. In addition, it has been postulated that use of IL-1 blockade as first-line therapy may take advantage of a window of opportunity, in which disease pathophysiology can be altered to prevent the occurrence of chronic arthritis. In this review, we analyze the published literature on IL-1 inhibitors in sJIA and discuss the rationale underlying the use of these medications, the results of therapeutic studies, and the controversial issues.

The fundamental role of endothelial cells in hantavirus pathogenesis

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Jussi eHepojoki

2014-12-01

Full Text Available Hantavirus, a genus of rodent- and insectivore-borne viruses in the family Bunyaviridae, is a group of emerging zoonotic pathogens. Hantaviruses cause hemorrhagic fever with renal syndrome (HFRS and hantavirus cardiopulmonary syndrome (HCPS in man, often with severe consequences. Vascular leakage is evident in severe hantavirus infections, and increased permeability contributes to the pathogenesis. This review summarizes the current knowledge on hantavirus interactions with endothelial cells, and their effects on the increased vascular permeability.

Renin-angiotensin system inhibition ameliorates CCl4-induced liver fibrosis in mice through the inactivation of nuclear transcription factor kappa B.

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Saber, Sameh; Mahmoud, Amr A A; Helal, Noha S; El-Ahwany, Eman; Abdelghany, Rasha H

2018-06-01

Therapeutic interventions for liver fibrosis are still limited due to the complicated molecular pathogenesis. Renin-angiotensin system (RAS) seems to contribute to the development of hepatic fibrosis. Therefore, we aimed to examine the effect of RAS inhibition on CCl 4 -induced liver fibrosis. Mice were treated with silymarin (30 mg·kg -1 ), perindopril (1 mg·kg -1 ), fosinopril (2 mg·kg -1 ), or losartan (10 mg·kg -1 ). The administration of RAS inhibitors improved liver histology and decreased protein expression of alpha smooth muscle actin (α-SMA) and hepatic content of hydroxyproline. These effects found to be mediated via inactivation of nuclear transcription factor kappa B (NFκB) pathway by the inhibition of NFκB p65 phosphorylation at the Ser536 residue and phosphorylation-induced degradation of nuclear factor kappa-B inhibitor alpha (NFκBia) subsequently inhibited NFκB-induced TNF-α and TGF-β1, leading to lower levels of tissue inhibitor of metalloproteinase-1 (TIMP-1) and vascular endothelial growth factor (VEGF). We concluded that the tissue affinity of the angiotensin converting enzyme inhibitors (ACEIs) has no impact on its antifibrotic activity and that interfering the RAS either through the inhibition of ACE or the blockade of AT1R has the same therapeutic benefit. These results suggest RAS inhibitors as promising candidates for further clinical trials in the management of hepatic fibrosis.

The role of adenoidal obstruction in the pathogenesis of Otitis media ...

African Journals Online (AJOL)

Background: Although adenoidectomy is generally applied in the treatment of otitis media with effusion (OME), there is still much debate about the role of adenoid in the pathogenesis of OME. The purpose of this study is to determine the incidence of OME in children with obstructive adenoid disease in comparison with ...

Studies on the pathogenesis and management of prostate carcinoma in dogs

NARCIS (Netherlands)

L'Eplattenier, H.F.

2009-01-01

The dog is one of the few species to develop spontaneous prostate carcinoma (PCA) and is thus an attractive model for the study of the disease in humans. Many of the features of the disease in the dog are similar to its human counterpart, however a number of aspects of the pathogenesis, diagnosis

Atractylenolide I restores HO-1 expression and inhibits Ox-LDL-induced VSMCs proliferation, migration and inflammatory responses in vitro

Energy Technology Data Exchange (ETDEWEB)

Li, Weifeng, E-mail: liwf@mail.xjtu.edu.cn; Zhi, Wenbing; Liu, Fang; He, Zehong; Wang, Xiuei; Niu, Xiaofeng, E-mail: niuxf@mail.xjtu.edu.cn

2017-04-01

Pathogenesis of atherosclerosis is characterized by the proliferation and migration of vascular smooth muscle cells (VSMCs) and inflammatory lesions. The aim of this study is to elucidate the effect of atractylenolide I (AO-I) on smooth muscle cell inflammation, proliferation and migration induced by oxidized modified low density lipoprotein (Ox-LDL). Here, We found that atractylenolide I inhibited Ox-LDL-induced VSMCs proliferation and migration in a dose-dependent manner, and decreased the production of inflammatory cytokines and the expression of monocyte chemoattractant protein-1 (MCP-1) in VSMCs. The study also identified that AO-I prominently inhibited p38-MAPK and NF-κB activation. More importantly, the specific heme oxygenase-1 (HO-1) inhibitor zinc protoporphyrin (ZnPP) IX partially abolished the beneficial effects of atractylenolide I on Ox-LDL-induced VSMCs. Furthermore, atractylenolide I blocked the foam cell formation in macrophages induced by Ox-LDL. In summary, inhibitory roles of AO-I in VSMCs proliferation and migration, lipid peroxidation and subsequent inflammatory responses might contribute to the anti-atherosclerotic property of AO-I. - Highlights: • AO-I inhibited Ox-LDL-induced VSMCs proliferation and migration. • AO-I alleviated inflammatory response via inhibiting TNF-α, IL-6 and NO production. • AO-I restored HO-1 expression and down-regulated PCNA expression. • MCP-1 overexpression is potentially regulated by NF-κB and p38 MAPK pathway. • AO-I possesses strong anti-lipid peroxidation effect.

Understanding rare disease pathogenesis: a grand challenge for model organisms.

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Hieter, Philip; Boycott, Kym M

2014-10-01

In this commentary, Philip Hieter and Kym Boycott discuss the importance of model organisms for understanding pathogenesis of rare human genetic diseases, and highlight the work of Brooks et al., "Dysfunction of 60S ribosomal protein L10 (RPL10) disrupts neurodevelopment and causes X-linked microcephaly in humans," published in this issue of GENETICS. Copyright © 2014 by the Genetics Society of America.

Biology of Acinetobacter baumannii: Pathogenesis, Antibiotic Resistance Mechanisms, and Prospective Treatment Options

Science.gov (United States)

Lee, Chang-Ro; Lee, Jung Hun; Park, Moonhee; Park, Kwang Seung; Bae, Il Kwon; Kim, Young Bae; Cha, Chang-Jun; Jeong, Byeong Chul; Lee, Sang Hee

2017-01-01

Acinetobacter baumannii is undoubtedly one of the most successful pathogens responsible for hospital-acquired nosocomial infections in the modern healthcare system. Due to the prevalence of infections and outbreaks caused by multi-drug resistant A. baumannii, few antibiotics are effective for treating infections caused by this pathogen. To overcome this problem, knowledge of the pathogenesis and antibiotic resistance mechanisms of A. baumannii is important. In this review, we summarize current studies on the virulence factors that contribute to A. baumannii pathogenesis, including porins, capsular polysaccharides, lipopolysaccharides, phospholipases, outer membrane vesicles, metal acquisition systems, and protein secretion systems. Mechanisms of antibiotic resistance of this organism, including acquirement of β-lactamases, up-regulation of multidrug efflux pumps, modification of aminoglycosides, permeability defects, and alteration of target sites, are also discussed. Lastly, novel prospective treatment options for infections caused by multi-drug resistant A. baumannii are summarized. PMID:28348979

The role of EBV in MS pathogenesis

DEFF Research Database (Denmark)

Christensen, Tove

2006-01-01

Environmental factors operate on a background of genetic susceptibility in the pathogenesis of MS. Human herpesviruses, notably Epstein-Barr virus (EBV), and human endogenous retroviruses are factors associated with MS. EBV association is found in epidemiological surveys where late EBV infection...... confers a higher risk of MS, and EBV reactivation also appears to be linked to disease activity in early MS. MS patients have elevated anti-EBV antibody responses, both in serum and cerebrospinal fluid. Molecular mimicry is found between certain EBV and myelin epitopes in the cell-mediated immune response....... EBV cannot stand alone as a causal factor of MS, but is likely to play an indirect role as an activator of the underlying disease process....

Actinic Keratosis Pathogenesis Update and New Patents.

Science.gov (United States)

Cantisani, Carmen; Paolino, Giovanni; Melis, Marcello; Faina, Valentina; Romaniello, Federico; Didona, Dario; Cardone, Michele; Calvieri, Stefano

2016-01-01

Actinic keratosis is a common premalignant skin lesion. Because of its increasing incidence, several efforts have been made to earlier detectection and to improve knowledge on photocarcinogenic pathways of keratinocytes. As a consequence, recently new discoveries have been done in this field. Starting from our previous review on actinic keratosis, we reviewed the literature focusing on pathogenesis and new patents in order to highlight the most recent progresses in diagnosis and therapeutic approach. Although several efforts have been done in the field of photodamaged skin, new upgrades in diagnosis and therapy are needed to detect superficial actinic keratosis earlier, to improve the disease free survival of patient and to better treat the field cancerization.

Pathogenesis of Insulin Resistance in Skeletal Muscle

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Muhammad A. Abdul-Ghani

2010-01-01

Full Text Available Insulin resistance in skeletal muscle is manifested by decreased insulin-stimulated glucose uptake and results from impaired insulin signaling and multiple post-receptor intracellular defects including impaired glucose transport, glucose phosphorylation, and reduced glucose oxidation and glycogen synthesis. Insulin resistance is a core defect in type 2 diabetes, it is also associated with obesity and the metabolic syndrome. Dysregulation of fatty acid metabolism plays a pivotal role in the pathogenesis of insulin resistance in skeletal muscle. Recent studies have reported a mitochondrial defect in oxidative phosphorylation in skeletal muscle in variety of insulin resistant states. In this review, we summarize the cellular and molecular defects that contribute to the development of insulin resistance in skeletal muscle.

Molecular cloning and characterisation of a pathogenesis-related protein CsPR10 from Crocus sativus.

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Gómez-Gómez, L; Rubio-Moraga, A; Ahrazem, O

2011-03-01

Plants have developed many mechanisms to protect themselves against most potential microbial pathogens and diseases. Among these mechanisms, pathogenesis-related proteins are produced as part of the active defence to prevent attack. In this study, a full-length cDNA encoding the CsPR10 protein was identified in fresh saffron stigmas (Crocus sativus). The deduced amino acid sequence from the nucleotide sequence of the coding region showed homology with PR10 proteins. The clone expressed as a protein in fusion with a GST tag produced a 47-kDa protein in E. coli. CsPR10 had ribonuclease activity, with features common to class II-type ribonucleases; its specific activity was quantified as 68.8 U·mg(-1) protein, thus falling within the range of most PR10 proteins exhibiting RNase activity. Antifungal activity of CsPR10 was assayed against Verticillium dahliae, Penicillium sp. and Fusarium oxysporum. CsPR10 inhibited only F. oxysporum growth, and antifungal potency was reflected in a IC(50) of 8.3 μm. Expression analysis showed the presence of high transcript levels in anther and tepal tissues, low levels in stigmas and roots, and no signal detected in leaves. This protein seems to be involved in the active defence response through activation of the jasmonic acid pathway. © 2010 German Botanical Society and The Royal Botanical Society of the Netherlands.

Salivary proteomics in lichen planus: A relationship with pathogenesis?

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Souza, M M; Florezi, G P; Nico, Mms; de Paula, F; Paula, F M; Lourenço, S V

2018-01-30

Oral lichen planus is a chronic, T-cell-mediated, inflammatory disease that affects the oral cavity. The oral lichen planus pathogenesis is still unclear, however, the main evidence is that the mechanisms of activation of different T lymphocyte pathway induce apoptosis with an increase in Th1 and Th17 subtypes cells, triggered by the release of cytokines. This study analysed saliva proteomics to identify protein markers that might be involved in the pathogenesis and development of the disease. Proteins differentially expressed by oral lichen planus and healthy controls were screened using mass spectrometry; the proteins found in oral lichen planus were subjected to bioinformatics analysis, including gene ontology and string networks analysis. The multiplex analysis validation allowed the correlation between the proteins identified and the involved cytokines in Th17 response. One hundred and eight proteins were identified in oral lichen planus, of which 17 proteins showed a high interaction between them and indicated an association with the disease. Expression of these proteins was correlated with the triggering of cytokines, more specifically the Th17 cells. Proteins, such as S100A8, S100A9, haptoglobin, can trigger cytokines and might be associated with a pathological function and antioxidant activities in oral lichen planus. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.

Mesenchymal Stem Cells from Patients with Rheumatoid Arthritis Display Impaired Function in Inhibiting Th17 Cells

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Yue Sun

2015-01-01

Full Text Available Mesenchymal stem cells (MSCs possess multipotent and immunomodulatory properties and are suggested to be involved in the pathogenesis of immune-related diseases. This study explored the function of bone marrow MSCs from rheumatoid arthritis (RA patients, focusing on immunomodulatory effects. RA MSCs showed decreased proliferative activity and aberrant migration capacity. No significant differences were observed in cytokine profiles between RA and control MSCs. The effects of RA MSCs on proliferation of peripheral blood mononuclear cells (PBMCs and distribution of specific CD4+ T cell subtypes (Th17, Treg, and Tfh cells were investigated. RA MSCs appeared to be indistinguishable from controls in suppressing PBMC proliferation, decreasing the proportion of Tfh cells, and inducing the polarization of Treg cells. However, the capacity to inhibit Th17 cell polarization was impaired in RA MSCs, which was related to the low expression of CCL2 in RA MSCs after coculture with CD4+ T cells. These findings indicated that RA MSCs display defects in several important biological activities, especially the capacity to inhibit Th17 cell polarization. These functionally impaired MSCs may contribute to the development of RA disease.

Re-appraisal of keratinocytes' role in vitiligo pathogenesis

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Ola Ahmed Bakry

2018-01-01

Full Text Available Background: Vitiligo is a common pigmentary disorder. Studies on its pathogenesis extensively investigated melanocytes' abnormalities and few studies searched for keratinocytes' role in disease development. Liver X receptor-α (LXR-α is a member of nuclear hormone receptors that acts as a transcription factor. Its target genes are the main regulators of melanocyte functions. Aim: The aim of this study is to investigate keratinocytes' role in vitiligo pathogenesis through immunohistochemical expression of LXR-α in lesional, perilesional, and distant nonlesional vitiligo skin. Materials and Methods: This case–control study was carried out on 44 participants. These included 24 patients with vitiligo and 20 age- and sex-matched normal individuals as a control group. Biopsies, from cases, were taken from lesional, perilesional, and distant nonlesional areas. Evaluation was done using immunohistochemical technique. Results: Keratinocyte LXR-α expression was upregulated in the lesional and perilesional skin (follicular and interfollicular epidermis compared with control skin (P<0.001 for all. There was significant association between higher histoscore (H-score in lesional epidermis (P<0.001 and in hair follicle (P=0.001 and the presence of angiogenesis. There was significant association between higher H-score in lesional epidermis and suprabasal vacuolization (P=0.02. No significant association was found between H-score or expression percentage and clinical data of selected cases. Conclusion: LXR-α upregulation is associated with keratinocyte damage in vitiligo lesional skin that leads to decreased keratinocyte-derived mediators and growth factors supporting the growth and/or melanization of surrounding melanocytes. Therefore, melanocyte function and survival are affected.

Psoriatic arthritis: from pathogenesis to therapy.

LENUS (Irish Health Repository)

Fitzgerald, Oliver

2012-02-01

Psoriatic arthritis is a multigenic autoimmune disease that involves synovial tissue, entheseal sites and skin, and that may result in significant joint damage. Although there are no diagnostic tests for psoriatic arthritis, research has identified consistent features that help to distinguish the condition from other common rheumatic diseases. Comparison of HLA-B and HLA-C regions in psoriatic arthritis with those in psoriasis without joint involvement demonstrates significant differences, such that psoriatic arthritis cannot be viewed simply as a subset of genetically homogeneous psoriasis. T-cell receptor phenotypic studies have failed to identify antigen-driven clones, and an alternative hypothesis for CD8 stimulation involving innate immune signals is proposed. Finally, imaging studies have highlighted entheseal involvement in psoriatic arthritis, and it is possible that entheseal-derived antigens may trigger an immune response that is critically involved in disease pathogenesis.

Protein misfolding disorders: pathogenesis and intervention

DEFF Research Database (Denmark)

Gregersen, Niels

2006-01-01

of the functional structure of cellular proteins. Aberrant proteins, the result of production errors, inherited or acquired amino acid substitutions or damage, especially oxidative modifications, can in many cases not fold correctly and will be trapped in misfolded conformations. To rid the cell of misfolded...... be accompanied by a gain-of-function pathogenesis, which in many cases determines the pathological and clinical features. Examples are Parkinson and Huntington diseases. Although a number of strategies have been tried to decrease the amounts of accumulated and aggregated proteins, a likely future strategy seems......Newly synthesized proteins in the living cell must go through a folding process to attain their functional structure. To achieve this in an efficient fashion, all organisms, including humans, have evolved a large set of molecular chaperones that assist the folding as well as the maintenance...

Thrombocytopenia in leukemia: Pathogenesis and prognosis.

Science.gov (United States)

Shahrabi, Saeid; Behzad, Masumeh Maleki; Jaseb, Kaveh; Saki, Najmaldin

2018-02-20

Leukemias, a heterogeneous group of hematological disorders, are characterized by ineffective hematopoiesis and morphologic abnormalities of hematopoietic cells. Thrombocytopenia is a common problem among leukemia types that can lead to hemorrhagic complications in patients. The purpose of this review article is to identify the conditions associated with the incidence of thrombocytopenia in leukemias. It can be stated that although translocations have been considered responsible for this complication in many studies, other factors such as bone marrow failure, genes polymorphism, a mutation in some transcription factors, and the adverse effects of treatment could be associated with pathogenesis and poor prognosis of thrombocytopenia in leukemias. Considering the importance of thrombocytopenia in leukemias, it is hoped that the recognition of risk factors increasing the incidence of this complication in leukemic patients would be useful for prevention and treatment of this disorder.

STUDIES ON THE PATHOGENESIS OF FEVER

Science.gov (United States)

Atkins, Elisha; Wood, W. Barry

1955-01-01

Further studies have been made of a pyrogenic substance which appears in the circulation of rabbits during the course of experimental fever induced by injection of typhoid vaccine. With the use of a passive transfer method and pyrogen-tolerant recipients, the biological properties of this substance have been differentiated from those of the uncleared vaccine in the circulation. The newly identified factor resembles leucocytic pyrogen in the rapidity with which it produces fever and in its failure to exhibit cross-tolerance with bacterial pyrogen. This striking similarity of properties suggests that the circulating factor is of endogenous origin and may arise from cell injury. A close correlation between its presence in the circulation and the existence of fever has been demonstrated. The possible relationship of these findings to the pathogenesis of fever is evident. PMID:13271667

HEART FAILURE AND DIABETES MELLITUS: SELECTED ISSUES OF ETIOLOGY AND PATHOGENESIS, PROGNOSIS AND TREATMENT

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B. U. Mardanov

2016-01-01

Full Text Available This review is devoted to the study of issues relating to the features of associated course of chronic heart failure (CHF and diabetes mellitus (DM. The modern views on the epidemiology, pathogenesis of DM and CHF are systematized. The pathogenesis of diabetic cardiomyopathy is described in details. The results of the well-known studies that show the negative impact of DM on CHF prognosis are presented. The principles of CHF pathogenetic therapy in patients with DM including the role of neurohormonal modulators are analyzed. The results of multicenter studies in patients with CHF and concomitant DM type 2 show that almost all first-line drugs recommended for CHF treatment are effective in patients with DM.

Immunological Factors in the Pathogenesis and Treatment of Age-Related Macular Degeneration

NARCIS (Netherlands)

Kijlstra, A.; Heij, La E.C.; Hendrikse, F.

2005-01-01

Recent findings indicate that immunological factors are involved not only in the pathogenesis of age-related macular degeneration (AMD), but also in its treatment. Earlier data showing the presence of inflammatory cells in affected areas of AMD retinas support this statement. Although a possible

Salmonella Disrupts Host Endocytic Trafficking by SopD2-Mediated Inhibition of Rab7

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Vanessa M. D’Costa

2015-09-01

Full Text Available Intracellular bacterial pathogens of a diverse nature share the ability to evade host immunity by impairing trafficking of endocytic cargo to lysosomes for degradation, a process that is poorly understood. Here, we show that the Salmonella enterica type 3 secreted effector SopD2 mediates this process by binding the host regulatory GTPase Rab7 and inhibiting its nucleotide exchange. Consequently, this limits Rab7 interaction with its dynein- and kinesin-binding effectors RILP and FYCO1 and thereby disrupts host-driven regulation of microtubule motors. Our study identifies a bacterial effector capable of directly binding and thereby modulating Rab7 activity and a mechanism of endocytic trafficking disruption that may provide insight into the pathogenesis of other bacteria. Additionally, we provide a powerful tool for the study of Rab7 function, and a potential therapeutic target.

Pathogenesis of Nonsteroidal Anti-Inflammatory Drug Gastropathy: Clues to Preventative Therapy

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Salim MA Bastaki

1999-01-01

Full Text Available Gastric ulceration and bleeding are major impediments to the chronic use of nonsteroidal anti-inflammatory drugs (NSAIDs. The development of effective therapies for prevention of these adverse effects requires better understanding of their pathogenesis. Several features of NSAIDs contribute to the development of damage in the stomach, including the topical irritant effects of these drugs on the epithelium, impairment of the barrier properties of the mucosa, suppression of gastric prostaglandin synthesis, reduction of gastric mucosal blood flow and interference with the repair of superficial injury. The presence of acid in the lumen of the stomach also contributes to the pathogenesis of NSAID-induced ulcers and bleeding in a number of ways. Acid impairs the restitution process, interferes with hemostasis and can inactivate several growth factors that are important in mucosal integrity and repair. Profound suppression of gastric acid secretion has been shown to be effective in preventing NSAID-induced ulceration. There is a strong possibility that new NSAIDs entering the market will have greatly reduced toxicity in the gastrointestinal tract.

Arousal from sleep: implications for obstructive sleep apnea pathogenesis and treatment.

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Eckert, Danny J; Younes, Magdy K

2014-02-01

Historically, brief awakenings from sleep (cortical arousals) have been assumed to be vitally important in restoring airflow and blood-gas disturbances at the end of obstructive sleep apnea (OSA) breathing events. Indeed, in patients with blunted chemical drive (e.g., obesity hypoventilation syndrome) and in instances when other defensive mechanisms fail, cortical arousal likely serves an important protective role. However, recent insight into the pathogenesis of OSA indicates that a substantial proportion of respiratory events do not terminate with a cortical arousal from sleep. In many cases, cortical arousals may actually perpetuate blood-gas disturbances, breathing instability, and subsequent upper airway closure during sleep. This brief review summarizes the current understanding of the mechanisms mediating respiratory-induced cortical arousal, the physiological factors that influence the propensity for cortical arousal, and the potential dual roles that cortical arousal may play in OSA pathogenesis. Finally, the extent to which existing sedative agents decrease the propensity for cortical arousal and their potential to be therapeutically beneficial for certain OSA patients are highlighted.

Interleukin-1 beta induced transient diabetes mellitus in rats. A model of the initial events in the pathogenesis of insulin-dependent diabetes mellitus?

DEFF Research Database (Denmark)

Reimers, J I

1998-01-01

When aiming at preventing IDDM in man, knowledge of the molecular mechanisms leading to beta cell destruction may facilitate identification of new possible intervention modalities. A model of IDDM pathogenesis in man suggests that cytokines, and IL-1 in particular, are of major importance...... of preventing IDDM in man, the aim af this review was to investigate the effects of rhIL-1 beta on beta-cell function and viability in normal rats. This review discussed 1) the pharmacokinetics of IL-1 beta in rats as the basis for choice of route of administration and dose of rhIL-1 beta, 2) the effects...... and molecular mechanisms of IL-1 beta on temperature and food intake used as control parameters for successful injection of rhIL-1 beta in rats, 3) the effects of one or more injection of IL-1 beta on rat beta cell function, 4) the molecular mechanisms leading to IL-1 beta induced beta cell inhibition in vivo...

Resveratrol Suppresses Growth and Migration of Myelodysplastic Cells by Inhibiting the Expression of Elevated Cyclin D1 (CCND1).

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Zhou, Wei; Xu, Shilin; Ying, Yi; Zhou, Ruiqing; Chen, Xiaowei

2017-11-01

Myelodysplastic syndromes (MDS) are a group of heterogeneous diseases characterized by poorly formed blood cells. We wanted to elucidate the underlying molecular mechanism to better determine pathogenesis, prognosis, diagnosis, and treatment for patients with MDS. We compared gene expression levels between normal and MDS tissue samples by immunohistochemical analysis. We studied the proliferation, survival, and migration of MDS cells using the EDU assay, colony formation, and transwell assays. We assessed the apoptotic rate and cell cycle status using flow cytometry and Hoechst staining. Finally, we evaluated RNA and protein expressions using polymerase chain reaction and Western blots, respectively. We found that resveratrol suppressed SKM-1 (an advanced MDS cell line) proliferation in a dose-dependent manner. Consistent with this finding, the EDU and colony formation assays also showed that resveratrol inhibited SKM-1 growth. Moreover, flow cytometry and Hoechst 33258 staining demonstrated that resveratrol induced apoptosis and a change in cell cycle status in SKM-1 cells, while the transwell assay showed that resveratrol reduced the migratory ability of SKM-1 cells. Resveratrol also decreased the expression of CCND1 (a gene that encodes the cyclin D1 protein) and increased expressions of KMT2A [lysine (K)-specific methyltransferase 2A] and caspase-3, suggesting that resveratrol exerts its effect by regulating CCND1 in SKM-1 cells. In addition, a combination of resveratrol and the PI3K/AKT inhibitor LY294002 exhibited a stronger inhibitory effect on the SKM-1 cells, compared with resveratrol alone. Our study proved that resveratrol suppresses SKM-1 growth and migration by inhibiting CCND1 expression. This finding provides novel insights into the pathogenesis of MDS and might help develop new diagnosis and treatment for patients with MDS.

Quorum Sensing Inhibition and Structure–Activity Relationships of β-Keto Esters

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Stephanie Forschner-Dancause

2016-07-01

Full Text Available Traditional therapeutics to treat bacterial infections have given rise to multi-drug resistant pathogens, which pose a major threat to human and animal health. In several pathogens, quorum sensing (QS—a cell-cell communication system in bacteria—controls the expression of genes responsible for pathogenesis, thus representing a novel target in the fight against bacterial infections. Based on the structure of the autoinducers responsible for QS activity and other QS inhibitors, we hypothesize that β-keto esters with aryl functionality could possess anti-QS activity. A panel of nineteen β-keto ester analogs was tested for the inhibition of bioluminescence (a QS-controlled phenotype in the marine pathogen Vibrio harveyi. Initial screening demonstrated the need of a phenyl ring at the C-3 position for antagonistic activity. Further additions to the phenyl ring with 4-substituted halo groups or a 3- or 4-substituted methoxy group resulted in the most active compounds with IC50 values ranging from 23 µM to 53 µM. The compounds additionally inhibit green fluorescent protein production by E. coli JB525. Evidence is presented that aryl β-keto esters may act as antagonists of bacterial quorum sensing by competing with N-acyl homoserine lactones for receptor binding. Expansion of the β-keto ester panel will enable us to obtain more insight into the structure–activity relationships needed to allow for the development of novel anti-virulence agents.

Targeted inhibition of the phosphoinositide 3-kinase impairs cell proliferation, survival, and invasion in colon cancer.

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Yang, Fei; Gao, Jun-Yi; Chen, Hua; Du, Zhen-Hua; Zhang, Xue-Qun; Gao, Wei

2017-01-01

Colon cancer is the third most common cancer in the world, and its metastasis and drug resistance are challenging for its effective treatment. The PI3K/Akt/mTOR pathway plays a crucial role in the pathogenesis of colon cancer. The aim of this study was to investigate the targeting of PI3K in colon cancer cells HT-29 and HCT-116 in vitro. In HT-29 and HCT-116 cells, BEZ235, a dual inhibitor of PI3K/mTOR, and shRNAtarget to PI3KCA were used to inhibit PI3K/Akt/mTOR pathway. The inhibition efficiency of PI3K/Akt/mTOR pathway was detected by RT-PCR and Western blot. Cell proliferation, migration, invasion, and apoptosis were evaluated by Cell Counting Kit-8, Transwell, and flow cytometry assays. The expression of apoptosis-related proteins (cleavage caspase 3, Bcl-2, Bax, and Bim) were also detected. We found that in HT-29 and HCT-116 cells, the treatment of BEZ235 (1 μM) and PI3KCA knockdown inhibited the activation of PI3K/Akt/mTOR pathway and significantly suppressed cell proliferation, migration, and invasion of HT-29 and HCT-116 cells. In addition, we confirmed that knockdown of BEZ235 and PI3KCA induced cell apoptosis through the upregulated levels of cleavage caspase 3 and Bax and downregulated expression of Bcl-2 and Bim. Our results indicated that targeted inhibition of the PI3K/Akt/mTOR pathway impaired cell proliferation, survival, and invasion in human colon cancer.

The efficacy of sarang semut extract (Myrmecodia pendens Merr & Perry in inhibiting Porphyromonas gingivalis biofilm formation

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Zulfan M. Alibasyah

2017-06-01

Full Text Available Background: Porphyromonas gingivalis (P. gingivalis is a pathogenic bacteria present in the oral cavity involved in the pathogenesis of chronic periodontitis and biofilm. This mass of microorganisms represents one of the virulent factors of P. gingivalis which plays an important role as an attachment initiator in host cells. Sarang semut is a natural material possessing the ability to inhibit the growth of P. gingivalis. Purpose: This study aims to analyze the effect of sarang semut extract on the formation of P. gingivalis biofilm. Methods: The study used methanol sarang semut extract and P. gingivalis ATCC 33277 and phosphomycin as a positive control. Treatment was initiated by means of culturing. Biofilm test and P. gingivalis biofilm formation observation were subsequently performed by means of a light microscope at a magnification of 400x. Results: The formation of P. gingivalis biofilms tended to increase at 3, 6, and 9 hours. Results of the violet crystal test showed that concentrations of 100% and 75% of the sarang semut extract successfully inhibited the formation of P. gingivalis biofilm according to the incubation time. Meanwhile, the sarang semut extracts at concentrations of 50%, 25%, 12.5%, and 6.125% resulted in weak inhibition of the formation of P. gingivalis biofilm. The biofilm mass profile observed by a microscope tended to decrease as an indicator of the effects of the sarang semut extract. Conclusion: Sarang semut extract can inhibit the formation of P. gingivalis biofilm, especially at concentrations of 100% and 75%. Nevertheless, phosphomycin has stronger antibiofilm of P. gingivalis effects than those of the sarang semut extract at all of the concentrations listed above.

Andrographolide inhibits the migration, invasion and matrix metalloproteinase expression of rheumatoid arthritis fibroblast-like synoviocytes via inhibition of HIF-1α signaling.

Science.gov (United States)

Li, Guo-feng; Qin, Yu-hua; Du, Peng-qiang

2015-09-01

Hypoxia is implicated in the pathogenesis of rheumatoid arthritis (RA), contributing to the tumor-like phenotypes of RA fibroblast-like synoviocytes (RA-FLSs). Andrographolide is the main bioactive component of Andrographis paniculata, an herbal medicine that shows therapeutic benefits in RA patients. Here, we explored the effects of andrographolide on hypoxia-induced migration and invasion of RA-FLSs. RA-FLSs were exposed to hypoxia in the presence or absence of andrographolide and cell migration and invasion were tested by Transwell assays. The expression of hypoxia-inducible factor-1 alpha (HIF-1α), matrix metalloproteinase (MMP)-1, MMP-3 and MMP-9 was measured by semi-quantitative reverse transcription polymerase chain reaction and Western blot analysis. HIF-1α DNA binding activity was assessed by electrophoretic mobility shift assay. The effects of overexpression of exogenous HIF-1α on the action of andrographolide in RA-FLSs were investigated. Andrographolide inhibited FLS migration and invasion under hypoxic conditions in a dose-dependent manner. The upregulation of MMP-1, MMP-3 and MMP-9 in response to hypoxia was significantly (Pandrographolide. Moreover, the expression and DNA binding activity of HIF-1α were dose-dependently decreased in andrographolide-treated cells under hypoxic conditions. Overexpression of HIF-1α almost completely reversed the suppressive effects of andrographolide on the migration, invasion and MMP expression of hypoxic RA-FLSs. These results indicate the ability of andrographolide to attenuate hypoxia-induced invasiveness of RA-FLSs via inhibition of HIF-1α signaling, and warrant further exploration of andrographolide for the treatment of RA. Copyright © 2015. Published by Elsevier Inc.

Kushenin induces the apoptosis of HCV-infected cells by blocking the PI3K-Akt-mTOR pathway via inhibiting NS5A

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Zhou, Yi; Chen, Na; Liu, Xiaojing; Lin, Shumei [Department of Infectious Diseases, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi 710061 (China); Luo, Wenjuan, E-mail: wenjuanluoxa@163.com [School of Pharmacy, Xi’an Jiaotong University, Xi’an, Shaanxi 710061 (China); Liu, Min, E-mail: minliusx@163.com [Department of Infectious Diseases, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi 710061 (China)

2016-07-01

With the increased burden induced by HCV, there is an urgent need to develop better-tolerated agents with good safety. In this study, we evaluated the anti-HCV capability of kushenin, as well as the possible mechanism to Huh7.5-HCV cells. The results demonstrated that kushenin significantly inhibited the HCV-RNA level. Similarly, the expression of HCV-specific protein NS5A was also decreased. Molecular docking results displayed that kushenin bonded well to the active pockets of HCV NS5A, further confirming the effects of kushenin on HCV replication. Coimmunoprecipitation assay determined that kushenin suppressed the interaction between PI3K and NS5A in HCV-replicon cells. Furthermore, kushenin exerted an obviously induced function on HCV-replicon cells apoptosis by inhibiting PI3K-Akt-mTOR pathway, which could be ameliorated by the specific activator IGF-1 addition. Taken together, kushenin possesses the ability to inhibit HCV replication, and contributes to the increased apoptosis of HCV-infected cells by blocking the PI3K-Akt-mTOR pathway via inhibiting NS5A. Our results provide important evidence for a better understanding of the pathogenesis of HCV infection, and suggest that kushenin has the potential to treat HCV disease. - Highlights: • Kushenin inhibits HCV replication. • Kushenin bonds directly to NS5A protein. • Kushenin induces the apoptosis of HCV-infected cells. • kushenin suppresses the interaction between PI3K and NS5A. • Kushenin inhibits PI3K-Akt-mTOR pathway.

Kushenin induces the apoptosis of HCV-infected cells by blocking the PI3K-Akt-mTOR pathway via inhibiting NS5A

International Nuclear Information System (INIS)

Zhou, Yi; Chen, Na; Liu, Xiaojing; Lin, Shumei; Luo, Wenjuan; Liu, Min

2016-01-01

With the increased burden induced by HCV, there is an urgent need to develop better-tolerated agents with good safety. In this study, we evaluated the anti-HCV capability of kushenin, as well as the possible mechanism to Huh7.5-HCV cells. The results demonstrated that kushenin significantly inhibited the HCV-RNA level. Similarly, the expression of HCV-specific protein NS5A was also decreased. Molecular docking results displayed that kushenin bonded well to the active pockets of HCV NS5A, further confirming the effects of kushenin on HCV replication. Coimmunoprecipitation assay determined that kushenin suppressed the interaction between PI3K and NS5A in HCV-replicon cells. Furthermore, kushenin exerted an obviously induced function on HCV-replicon cells apoptosis by inhibiting PI3K-Akt-mTOR pathway, which could be ameliorated by the specific activator IGF-1 addition. Taken together, kushenin possesses the ability to inhibit HCV replication, and contributes to the increased apoptosis of HCV-infected cells by blocking the PI3K-Akt-mTOR pathway via inhibiting NS5A. Our results provide important evidence for a better understanding of the pathogenesis of HCV infection, and suggest that kushenin has the potential to treat HCV disease. - Highlights: • Kushenin inhibits HCV replication. • Kushenin bonds directly to NS5A protein. • Kushenin induces the apoptosis of HCV-infected cells. • kushenin suppresses the interaction between PI3K and NS5A. • Kushenin inhibits PI3K-Akt-mTOR pathway.

An Angiotensin II Type 1 Receptor Blocker Prevents Renal Injury via Inhibition of the Notch Pathway in Ins2 Akita Diabetic Mice

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Masaya Koshizaka

2012-01-01

Full Text Available Recently, it has been reported that the Notch pathway is involved in the pathogenesis of diabetic nephropathy. In this study, we investigated the activation of the Notch pathway in Ins2 Akita diabetic mouse (Akita mouse and the effects of telmisartan, an angiotensin II type1 receptor blocker, on the Notch pathway. The intracellular domain of Notch1 (ICN1 is proteolytically cleaved from the cell plasma membrane in the course of Notch activation. The expression of ICN1 and its ligand, Jagged1, were increased in the glomeruli of Akita mice, especially in the podocytes. Administration of telmisartan significantly ameliorated the expression of ICN1 and Jagged1. Telmisartan inhibited the angiotensin II-induced increased expression of transforming growth factor β and vascular endothelial growth factor A which could directly activate the Notch signaling pathway in cultured podocytes. Our results indicate that the telmisartan prevents diabetic nephropathy through the inhibition of the Notch pathway.

UTIs in small animal patients: part 1: etiology and pathogenesis.

Science.gov (United States)

Smee, Nicole; Loyd, Kimberly; Grauer, Greg

2013-01-01

Understanding how urinary tract infections (UTIs) can occur and how to classify them can help the practitioner to make a plan for treatment. This review summarizes the etiology, pathogenesis, and host defense mechanisms associated with bacterial UTIs in dogs and cats. UTIs in Small Animal Patients: Part 2: Diagnosis, Treatment, and Complications will appear in the March/April 2013 issue of the Journal of the American Animal Hospital Association.

Achondroplasia: Development, pathogenesis, and therapy.

Science.gov (United States)

Ornitz, David M; Legeai-Mallet, Laurence

2017-04-01

Autosomal dominant mutations in fibroblast growth factor receptor 3 (FGFR3) cause achondroplasia (Ach), the most common form of dwarfism in humans, and related chondrodysplasia syndromes that include hypochondroplasia (Hch), severe achondroplasia with developmental delay and acanthosis nigricans (SADDAN), and thanatophoric dysplasia (TD). FGFR3 is expressed in chondrocytes and mature osteoblasts where it functions to regulate bone growth. Analysis of the mutations in FGFR3 revealed increased signaling through a combination of mechanisms that include stabilization of the receptor, enhanced dimerization, and enhanced tyrosine kinase activity. Paradoxically, increased FGFR3 signaling profoundly suppresses proliferation and maturation of growth plate chondrocytes resulting in decreased growth plate size, reduced trabecular bone volume, and resulting decreased bone elongation. In this review, we discuss the molecular mechanisms that regulate growth plate chondrocytes, the pathogenesis of Ach, and therapeutic approaches that are being evaluated to improve endochondral bone growth in people with Ach and related conditions. Developmental Dynamics 246:291-309, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Molecular Pathogenesis of MALT Lymphoma

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Katharina Troppan

2015-01-01

Full Text Available Approximately 8% of all non-Hodgkin lymphomas are extranodal marginal zone B cell lymphoma of mucosa associated lymphoid tissue (MALT, also known as MALT lymphoma, which was first described in 1983 by Isaacson and Wright. MALT lymphomas arise at a wide range of different extranodal sites, with the highest frequency in the stomach, followed by lung, ocular adnexa, and thyroid, and with a low percentage in the small intestine. Interestingly, at least 3 different, apparently site-specific, chromosomal translocations and missense and frameshift mutations, all pathway-related genes affecting the NF-κB signal, have been implicated in the development and progression of MALT lymphoma. However, these genetic abnormalities alone are not sufficient for malignant transformation. There is now increasing evidence suggesting that the oncogenic product of translocation cooperates with immunological stimulation in oncogenesis, that is, the association with chronic bacterial infection or autoaggressive process. This review mainly discusses MALT lymphomas in terms of their genetic aberration and association with chronic infections and summarizes recent advances in their molecular pathogenesis.

TG101209, a small molecule JAK2-selective kinase inhibitor potently inhibits myeloproliferative disorder-associated JAK2V617F and MPLW515L/K mutations.

Science.gov (United States)

Pardanani, A; Hood, J; Lasho, T; Levine, R L; Martin, M B; Noronha, G; Finke, C; Mak, C C; Mesa, R; Zhu, H; Soll, R; Gilliland, D G; Tefferi, A

2007-08-01

JAK2V617F and MPLW515L/K represent recently identified mutations in myeloproliferative disorders (MPD) that cause dysregulated JAK-STAT signaling, which is implicated in MPD pathogenesis. We developed TG101209, an orally bioavailable small molecule that potently inhibits JAK2 (IC(50)=6 nM), FLT3 (IC(50)=25 nM) and RET (IC(50)=17 nM) kinases, with significantly less activity against other tyrosine kinases including JAK3 (IC(50)=169 nM). TG101209 inhibited growth of Ba/F3 cells expressing JAK2V617F or MPLW515L mutations with an IC(50) of approximately 200 nM. In a human JAK2V617F-expressing acute myeloid leukemia cell line, TG101209-induced cell cycle arrest and apoptosis, and inhibited phosphorylation of JAK2V617F, STAT5 and STAT3. Therapeutic efficacy of TG101209 was demonstrated in a nude mouse model. Furthermore, TG101209 suppressed growth of hematopoietic colonies from primary progenitor cells harboring JAK2V617F or MPL515 mutations.

3',5'-Cyclic diguanylic acid (c-di-GMP) inhibits basal and growth factor-stimulated human colon cancer cell proliferation

International Nuclear Information System (INIS)

Karaolis, David K.R.; Cheng, Kunrong; Lipsky, Michael; Elnabawi, Ahmed; Catalano, Jennifer; Hyodo, Mamoru; Hayakawa, Yoshihiro; Raufman, Jean-Pierre

2005-01-01

The novel cyclic dinucleotide, 3',5'-cyclic diguanylic acid, cGpGp (c-di-GMP), is a naturally occurring small molecule that regulates important signaling mechanisms in prokaryotes. Recently, we showed that c-di-GMP has 'drug-like' properties and that c-di-GMP treatment might be a useful antimicrobial approach to attenuate the virulence and pathogenesis of Staphylococcus aureus and prevent or treat infection. In the present communication, we report that c-di-GMP (≤50 μM) has striking properties regarding inhibition of cancer cell proliferation in vitro. c-di-GMP inhibits both basal and growth factor (acetylcholine and epidermal growth factor)-induced cell proliferation of human colon cancer (H508) cells. Toxicity studies revealed that exposure of normal rat kidney cells and human neuroblastoma cells to c-di-GMP at biologically relevant doses showed no lethal cytotoxicity. Cyclic dinucleotides, such as c-di-GMP, represent an attractive and novel 'drug-platform technology' that can be used not only to develop new antimicrobial agents, but also to develop novel therapeutic agents to prevent or treat cancer

Curcumin Inhibits NTHi-Induced MUC5AC Mucin Overproduction in Otitis Media via Upregulation of MAPK Phosphatase MKP-1

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Anuhya Sharma Konduru

2017-01-01

Full Text Available Otitis media (OM, characterized by the presence of mucus overproduction and excess inflammation in the middle ear, is the most common childhood infection. Nontypeable Haemophilus influenzae (NTHi pathogen is responsible for approximately one-third of episodes of bacteria-caused OM. Current treatments for bacterial OM rely on the systemic use of antibiotics, which often leads to the emergence of multidrug resistant bacterial strains. Therefore there is an urgent need for developing alternative therapies strategies for controlling mucus overproduction in OM. MUC5AC mucin has been shown to play a critical role in the pathogenesis of OM. Here we show that curcumin derived from Curcuma longa plant is a potent inhibitor of NTHi-induced MUC5AC mucin expression in middle ear epithelial cells. Curcumin inhibited MUC5AC expression by suppressing activation of p38 MAPK by upregulating MAPK phosphatase MKP-1. Thus, our study identified curcumin as a potential therapeutic for inhibiting mucin overproduction in OM by upregulating MKP-1, a known negative regulator of inflammation.

Gut microbiota in relation to pathogenesis of obesity and type 2 diabetes

NARCIS (Netherlands)

Udayappan, S.D.

2018-01-01

Alterations in the gut microbiota composition are strongly associated with the pathogenesis of obesity and Type 2 diabetes (T2DM). In this thesis, we investigated the putative role of the gut microbiota in human metabolic diseases. In this context, intestinal bacteria such as Eubacterium hallii and

Perindopril, fosinopril and losartan inhibited the progression of diethylnitrosamine-induced hepatocellular carcinoma in mice via the inactivation of nuclear transcription factor kappa-B.

Science.gov (United States)

Saber, Sameh; Mahmoud, Amr A A; Goda, Reham; Helal, Noha S; El-Ahwany, Eman; Abdelghany, Rasha H

2018-05-31

Hepatocellular carcinoma (HCC) is a major global health problem. Therapeutic interventions of HCC are still limited because of its complicated molecular pathogenesis. Many reports showed that renin-angiotensin system (RAS) contributes to the development of different types of malignancies. Therefore, the present study aimed to examine the effect of RAS inhibition using perindopril (1 mg/kg), fosinopril (2 mg/kg), or losartan (10 mg/kg) on diethylnitrosamine-induced HCC compared to sorafenib (30 mg/kg). The administration of RAS inhibitors resulted in improved liver function and histologic picture with a reduction in AFP levels. These effects found to be mediated through inactivation of NFкB pathway by the inhibition of NFĸB p65 phosphorylation at the Ser536 residue and inhibition of the phosphorylation-induced degradation of NFĸBia. Consequently, expression levels of cyclin D1 mRNA were significantly lowered. In addition, NFкB-induced TNF-α and TGF-β1 levels were reduced leading to lower levels of MMP-2 and VEGF. We concluded that RAS inhibition either through inhibiting the ACE or the blockade of AT1R has the same therapeutic benefit and that the tissue affinity of the ACEIs has no impact on its anti-tumor activity. These results suggest that ACEIs and ARBs can serve as promising candidates for further clinical trials in the management of HCC. Copyright © 2018 Elsevier B.V. All rights reserved.

A Possible Role of Intestinal Microbiota in the Pathogenesis of Ankylosing Spondylitis

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Lianjun Yang

2016-12-01

Full Text Available Ankylosing spondylitis (AS is a chronic inflammatory disease primarily affecting the sacroiliac joints and the spine, for which the pathogenesis is thought to be a result of the combination of host genetic factors and environmental triggers. However, the precise factors that determine one’s susceptibility to AS remain to be unraveled. With 100 trillion bacteria residing in the mammalian gut having established a symbiotic relation with their host influencing many aspects of host metabolism, physiology, and immunity, a growing body of evidence suggests that intestinal microbiota may play an important role in AS. Several mechanisms have been suggested to explain the potential role of the microbiome in the etiology of AS, such as alterations of intestinal permeability, stimulation of immune responses, and molecular mimicry. In this review, the existing evidence for the involvement of the microbiome in AS pathogenesis was discussed and the potential of intestinal microbiome-targeting strategies in the prevention and treatment of AS was evaluated.

Urine metabolic profiling for the pathogenesis research of erosive oral lichen planus.

Science.gov (United States)

Li, Xu-Zhao; Yang, Xu-Yan; Wang, Yu; Zhang, Shuai-Nan; Zou, Wei; Wang, Yan; Li, Xiao-Nan; Wang, Ling-Shu; Zhang, Zhi-Gang; Xie, Liang-Zhen

2017-01-01

Oral lichen planus (OLP) is a relatively common chronic immune-pathological and inflammatory disease and potentially oral precancerous lesion. Erosive OLP patients show the higher rate of malignant transformation than patients with non-erosive OLP. Identifying the potential biomarkers related to erosive OLP may help to understand the pathogenesis of the diseases. Metabolic profiles were compared in control and patient subjects with erosive OLP by using ultra-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UPLC-QTOF-MS) coupled with pattern recognition methods An integrative analysis was used to identify the perturbed metabolic pathways and pathological processes that may be associated with the disease. In total, 12 modulated metabolites were identified and considered as the potential biomarkers of erosive OLP. Multiple metabolic pathways and pathological processes were involved in erosive OLP. The dysregulations of these metabolites could be used to explain the pathogenesis of the disease, which could also be the potential therapeutic targets for the disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

Occipital plagiocephaly: deformation or lambdoid synostosis ? II. a unifying theory regarding pathogenesis

International Nuclear Information System (INIS)

Dias, M.S.; Klein, D.M.

1997-01-01

Occipital plagiocephaly is characterized by both unilateral occipital flattening and ipsilateral frontal prominence with anterior deviation of the ipsilateral ear, yielding a characteristic parallelogram shape to the cranium. Radiographic changes in the lambdoid suture are often evident, but the lambdoid suture is usually patent over most or all of its length on skull X-rays and/or CT scans. Both lambdoid synostosis and deformational forces have been implicated as potentially causal in the pathogenesis of this deformity. We propose a unifying theory which incorporates a common pathogenesis for both deformational plagiocephaly and most cases of lambdoid ''synostosis''. According to this hypothesis, intrauterine and/or postnatal deformational forces are responsible for the primary calvarial deformation. These forces initially act in a reversible manner to produce the typical parallelogram-shaped skull deformity. How-ever, with continued deformation, more enduring secondary pathological changes may eventually occur in the lambdoid suture and basicranium which are more difficult to correct even if the offending deformational forces are subsequently removed or reversed. (authors)

Immunological Mechanisms Implicated in the Pathogenesis of Chronic Urticaria and Hashimoto Thyroiditis.

Science.gov (United States)

Berghi, Nicolae Ovidiu

2017-08-01

Autoimmunity represents the attack of the immune system of an organism against its own cells and tissues. Autoimmune diseases may affect one organ (Hashimoto thyroiditis) or can be systemic (chronic urticaria). Many factors are implicated in the pathogenesis of autoimmunity (white cells, cytokines, chemokines). Hashimoto thyroiditis has been associated with chronic urticaria in the last 3 decades in a number of clinical studies. Anti-thyroid antibodies have been documented in a proportion ranging from 10% to 30% in chronic urticaria patients in different countries from 3 continents. Two of the factors involved in the mechanism of autoimmunity are present both in the pathophysiology of Hashimoto thyroiditis and chronic urticaria. According to recent studies, IL6 is implicated in the pathogenesis of both diseases. TregsCD4+CD25+Foxp3+ cells have also been implicated in the pathological mechanisms of these 2 entities. This review offers an explanation of the clinical and statistical association between these two diseases from the pathophysiological point of view.

Hydroxychavicol, a novel betel leaf component, inhibits platelet aggregation by suppression of cyclooxygenase, thromboxane production and calcium mobilization.

Science.gov (United States)

Chang, M C; Uang, B J; Tsai, C Y; Wu, H L; Lin, B R; Lee, C S; Chen, Y J; Chang, C H; Tsai, Y L; Kao, C J; Jeng, J H

2007-09-01

Platelet hyperactivity is important in the pathogenesis of cardiovascular diseases. Betel leaf (PBL) is consumed by 200-600 million betel quid chewers in the world. Hydroxychavicol (HC), a betel leaf component, was tested for its antiplatelet effect. We tested the effect of HC on platelet aggregation, thromboxane B(2) (TXB(2)) and reactive oxygen species (ROS) production, cyclooxygenase (COX) activity, ex vivo platelet aggregation and mouse bleeding time and platelet plug formation in vivo. The pharmacokinetics of HC in rats was also assessed. HC inhibited arachidonic acid (AA) and collagen-induced platelet aggregation and TXB(2) production. HC inhibited the thrombin-induced TXB(2) production, but not platelet aggregation. SQ29548, suppressed collagen- and thrombin-induced TXB(2) production, but not thrombin-induced platelet aggregation. HC also suppressed COX-1/COX-2 enzyme activity and the AA-induced ROS production and Ca(2+) mobilization. HC further inhibited the ex vivo platelet aggregation of platelet-rich plasma (>100 nmole/mouse) and prolonged platelet plug formation (>300 nmole/mouse) in mesenteric microvessels, but showed little effect on bleeding time in mouse tail. Moreover, pharmacokinetics analysis found that more than 99% of HC was metabolized within 3 min of administration in Sprague-Dawley rats in vivo. HC is a potent COX-1/COX-2 inhibitor, ROS scavenger and inhibits platelet calcium signaling, TXB(2) production and aggregation. HC could be a potential therapeutic agent for prevention and treatment of atherosclerosis and other cardiovascular diseases through its anti-inflammatory and antiplatelet effects, without effects on haemostatic functions.

Wild-Type, but Not Mutant N296H, Human Tau Restores Aβ-Mediated Inhibition of LTP in Tau−/− mice

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Mariana Vargas-Caballero

2017-04-01

Full Text Available Microtubule associated protein tau (MAPT is involved in the pathogenesis of Alzheimer's disease and many forms of frontotemporal dementia (FTD. We recently reported that Aβ-mediated inhibition of hippocampal long-term potentiation (LTP in mice requires tau. Here, we asked whether expression of human MAPT can restore Aβ-mediated inhibition on a mouse Tau−/− background and whether human tau with an FTD-causing mutation (N296H can interfere with Aβ-mediated inhibition of LTP. We used transgenic mouse lines each expressing the full human MAPT locus using bacterial artificial chromosome technology. These lines expressed all six human tau protein isoforms on a Tau−/− background. We found that the human wild-type MAPT H1 locus was able to restore Aβ42-mediated impairment of LTP. In contrast, Aβ42 did not reduce LTP in slices in two independently generated transgenic lines expressing tau protein with the mutation N296H associated with frontotemporal dementia (FTD. Basal phosphorylation of tau measured as the ratio of AT8/Tau5 immunoreactivity was significantly reduced in N296H mutant hippocampal slices. Our data show that human MAPT is able to restore Aβ42-mediated inhibition of LTP in Tau−/− mice. These results provide further evidence that tau protein is central to Aβ-induced LTP impairment and provide a valuable tool for further analysis of the links between Aβ, human tau and impairment of synaptic function.

Botryoid odontogenic cyst developing from lateral periodontal cyst: A rare case and review on pathogenesis

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Piyush Arora

2012-01-01

Full Text Available Botryoid odontogenic cyst (BOC is considered to be a polycystic variant of the lateral periodontal cyst (LPC as the specimen resembled a cluster of grapes. It is a non-inflammatory odontogenic cyst. The BOCs can be unicystic or multicystic. These cysts have potential to extend in the bone and become multilocular and they have a high recurrence rate. Till now, only 73 cases of BOC have been reported. The pathogenesis of BOC is still debatable. We review different pathogenesis proposed for BOC and discuss a rare case of BOC developing from lining of an abnormally large LPC which showed aggressive behaviour in terms of growth and size.

How a sugary bug gets through the day: Recent developments in understanding fundamental processes impacting Campylobacter jejuni pathogenesis

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Szymanski, Christine M.; Gaynor, Erin

2012-01-01

Campylobacter jejuni is a highly prevalent yet fastidious bacterial pathogen that poses a significant health burden worldwide. Lacking many hallmark virulence factors, it is becoming increasingly clear that C. jejuni pathogenesis involves different strategies compared with other well-characterized enteric organisms. This includes the involvement of basic biological processes and cell envelope glycans in a number of aspects related to pathogenesis. The past few years have seen significant prog...

Diet, gut microbes, and the pathogenesis of inflammatory bowel diseases.

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Dolan, Kyle T; Chang, Eugene B

2017-01-01

The rising incidence of inflammatory bowel diseases in recent decades has notably paralleled changing lifestyle habits in Western nations, which are now making their way into more traditional societies. Diet plays a key role in IBD pathogenesis, and there is a growing appreciation that the interaction between diet and microbes in a susceptible person contributes significantly to the onset of disease. In this review, we examine what is known about dietary and microbial factors that promote IBD. We summarize recent findings regarding the effects of diet in IBD epidemiology from prospective population cohort studies, as well as new insights into IBD-associated dysbiosis. Microbial metabolism of dietary components can influence the epithelial barrier and the mucosal immune system, and understanding how these interactions generate or suppress inflammation will be a significant focus of IBD research. Our knowledge of dietary and microbial risk factors for IBD provides important considerations for developing therapeutic approaches through dietary modification or re-shaping the microbiota. We conclude by calling for increased sophistication in designing studies on the role of diet and microbes in IBD pathogenesis and disease resolution in order to accelerate progress in response to the growing challenge posed by these complex disorders. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Truncated prelamin A expression in HGPS-like patients: a transcriptional study

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Barthelemy, F.; Navarro, C; Fayek, R.; Silva, N.; Roll, P.; Sigaudy, S.; Oshima, J.; Bonne, G.; Papadopoulou-Legbelou, K.; Evangeliou, A.E.; Spilioti, M.; Lemerrer, M.; Wevers, R.A.; Morava, E.; Robaglia-Schlupp, A.; Levy, N.; Bartoli, M.; Sandre-Giovannoli, A. De

2015-01-01

Premature aging syndromes are rare genetic disorders mimicking clinical and molecular features of aging. A recently identified group of premature aging syndromes is linked to mutation of the LMNA gene encoding lamins A and C, and is associated with nuclear deformation and dysfunction.

Deregulation of protein translation control, a potential game-changing hypothesis for Parkinson's disease pathogenesis.

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Taymans, Jean-Marc; Nkiliza, Aurore; Chartier-Harlin, Marie-Christine

2015-08-01

Protein translation is one of the most fundamental and exquisitely controlled processes in biology, and is energetically demanding. The deregulation of this process is deleterious to cells, as demonstrated by several diseases caused by mutations in protein translation machinery. Emerging evidence now points to a role for protein translation in the pathogenesis of Parkinson's disease (PD); a debilitating neurodegenerative movement disorder. In this paper, we propose a hypothesis that protein translation machinery, PD-associated proteins and PD pathology are connected in a functional network linking cell survival to protein translation control. This hypothesis is a potential game changer in the field of the molecular pathogenesis of PD, with implications for the development of PD diagnostics and disease-modifying therapies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Clinical Relevance of Environmental Factors in the Pathogenesis of Autoimmune Thyroid Disease

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Wiersinga, Wilmar M.

2016-01-01

Genetic factors contribute for about 70% to 80% and environmental factors for about 20% to 30% to the pathogenesis of autoimmune thyroid disease (AITD). Relatives of AITD patients carry a risk to contract AITD themselves. The 5-year risk can be quantified by the so-called Thyroid Events

Epigenetic perturbations in the pathogenesis of mustard toxicity; hypothesis and preliminary results

International Nuclear Information System (INIS)

Korkmaz, A.; Yaren, H.; Kunak, I.; Uysal, B.; Kurt, B.; Topal, T.

2009-01-01

The pathogenesis of sulfur mustard (SM) toxicity is not fully understood, although it is related to reactive oxygen and nitrogen species, oxidative stress, DNA damage, poly (ADP-ribose) polymerase activation within the affected cell. We, therefore, made an attempt whether epigenetic aberrations may contribute to pathogenesis of SM poisoning in rats' lung. A total of 40 male SD rats were divided into 4 groups. Group 1 served as control and given 2 ml saline, three groups received single dose of mechlorethamine (MEC) (3.5 mg/kg subcutaneously) with the same time intervals. Group 2 received MEC only; group 3 received histone deacetylase (HDAC) inhibitor (Trichostatine A) (1 mg/kg) and group 4 received DNA methyl transferase (DNMT) inhibitor (5-Azacytidine) (0.02 mg/kg), intraperitoneally. MEC injection resulted in severe lung toxicity with strong interstitial and alveolar edema, hemorrhage, emphysematous changes as well as mild inflammatory cell infiltration and septal thickening. In group 3, the HDAC inhibitor significantly reduced interstitial and alveolar edema, hemorrhage and inflammatory cell infiltration. On the other hand, we have observed severe lung damage by using DNMT inhibitor (group 4). In HDAC inhibitor group, the results were close to sham group. In DNMT inhibitor group, however, lungs were worse than MEC group results. These preliminary results revealed that, SM itself and/or its intracellular metabolites may perturb the epigenetic environment of the affected cell in lung tissue. Hypothetically, MEC may cause HDAC induction leading to a variety of gene silencing. Trichostatine A can reduce the active enzyme level and can reactivate the already silenced genes. Further studies are needed to clarify the involvement of epigenetic perturbations in the pathogenesis of mustard toxicity.(author)

The complement system: a gateway to gene-environment interactions in schizophrenia pathogenesis.

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Nimgaonkar, V L; Prasad, K M; Chowdari, K V; Severance, E G; Yolken, R H

2017-11-01

The pathogenesis of schizophrenia is considered to be multi-factorial, with likely gene-environment interactions (GEI). Genetic and environmental risk factors are being identified with increasing frequency, yet their very number vastly increases the scope of possible GEI, making it difficult to identify them with certainty. Accumulating evidence suggests a dysregulated complement pathway among the pathogenic processes of schizophrenia. The complement pathway mediates innate and acquired immunity, and its activation drives the removal of damaged cells, autoantigens and environmentally derived antigens. Abnormalities in complement functions occur in many infectious and autoimmune disorders that have been linked to schizophrenia. Many older reports indicate altered serum complement activity in schizophrenia, though the data are inconclusive. Compellingly, recent genome-wide association studies suggest repeat polymorphisms incorporating the complement 4A (C4A) and 4B (C4B) genes as risk factors for schizophrenia. The C4A/C4B genetic associations have re-ignited interest not only in inflammation-related models for schizophrenia pathogenesis, but also in neurodevelopmental theories, because rodent models indicate a role for complement proteins in synaptic pruning and neurodevelopment. Thus, the complement system could be used as one of the 'staging posts' for a variety of focused studies of schizophrenia pathogenesis. They include GEI studies of the C4A/C4B repeat polymorphisms in relation to inflammation-related or infectious processes, animal model studies and tests of hypotheses linked to autoimmune diseases that can co-segregate with schizophrenia. If they can be replicated, such studies would vastly improve our understanding of pathogenic processes in schizophrenia through GEI analyses and open new avenues for therapy.

Positron emission tomography measurement of brain MAO-B inhibition in patients with Alzheimer's disease and elderly controls after oral administration of sembragiline

International Nuclear Information System (INIS)

Sturm, Stefan; Forsberg, Anton; Stenkrona, Per; Varrone, Andrea; Fazio, Patrik; Nakao, Ryuji; Halldin, Christer; Nave, Stephane; Jamois, Candice; Ricci, Benedicte; Seneca, Nicholas; Comley, Robert A.; Ejduk, Zbigniew; Al-Tawil, Nabil; Akenine, Ulrika; Andreasen, Niels

2017-01-01

In Alzheimer's disease (AD), increased metabolism of monoamines by monoamine oxidase type B (MAO-B) leads to the production of toxic reactive oxygen species (ROS), which are thought to contribute to disease pathogenesis. Inhibition of the MAO-B enzyme may restore brain levels of monoaminergic neurotransmitters, reduce the formation of toxic ROS and reduce neuroinflammation (reactive astrocytosis), potentially leading to neuroprotection. Sembragiline (also referred as RO4602522, RG1577 and EVT 302 in previous communications) is a potent, selective and reversible inhibitor of MAO-B developed as a potential treatment for AD. This study assessed the relationship between plasma concentration of sembragiline and brain MAO-B inhibition in patients with AD and in healthy elderly control (EC) subjects. Positron emission tomography (PET) scans using [ 11 C]- L -deprenyl-D 2 radiotracer were performed in ten patients with AD and six EC subjects, who received sembragiline each day for 6-15 days. At steady state, the relationship between sembragiline plasma concentration and MAO-B inhibition resulted in an E max of ∝80-90 % across brain regions of interest and in an EC 50 of 1-2 ng/mL. Data in patients with AD and EC subjects showed that near-maximal inhibition of brain MAO-B was achieved with 1 mg sembragiline daily, regardless of the population, whereas lower doses resulted in lower and variable brain MAO-B inhibition. This PET study confirmed that daily treatment of at least 1 mg sembragiline resulted in near-maximal inhibition of brain MAO-B enzyme in patients with AD. (orig.)

Pathogenesis of Brain Edema and Investigation into Anti-Edema Drugs

OpenAIRE

Shotaro Michinaga; Yutaka Koyama

2015-01-01

Brain edema is a potentially fatal pathological state that occurs after brain injuries such as stroke and head trauma. In the edematous brain, excess accumulation of extracellular fluid results in elevation of intracranial pressure, leading to impaired nerve function. Despite the seriousness of brain edema, only symptomatic treatments to remove edema fluid are currently available. Thus, the development of novel anti-edema drugs is required. The pathogenesis of brain edema is classified as vas...

The pathogenesis of allergic rhinitis : cellular aspects with special emphasis on Langerhans cells

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W.J. Fokkens (Wytske)

1991-01-01

textabstractPresent ideas concerning the pathogenesis of allergic rhinitis are largely deduced from systemic investigations and extrapolated from studies in the skin and the lung. Studies on allergic rhinitis generally comprise clinical aspects and/or biochemical, humoral and cellular features of

ENDOCRINE PATHOLOGY. ETIOLOGY AND PATHOGENESIS OF ENDOCRINOPATHY: DYSFUNCTION OF THYROID AND PARATHYROIND GLANDS

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P. F. Litvitskii

2012-01-01

Full Text Available This lecture deals with etiology, pathogenesis and clinical presentation of thyroid and parathyroid hyper — and hypofunction, adrenal pathology. This lecture is also supplemented with multiple choice tests and a clinical case with keys for self testing.

Bacterial Signaling Nucleotides Inhibit Yeast Cell Growth by Impacting Mitochondrial and Other Specifically Eukaryotic Functions

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Andy Hesketh

2017-07-01

Full Text Available We have engineered Saccharomyces cerevisiae to inducibly synthesize the prokaryotic signaling nucleotides cyclic di-GMP (cdiGMP, cdiAMP, and ppGpp in order to characterize the range of effects these nucleotides exert on eukaryotic cell function during bacterial pathogenesis. Synthetic genetic array (SGA and transcriptome analyses indicated that, while these compounds elicit some common reactions in yeast, there are also complex and distinctive responses to each of the three nucleotides. All three are capable of inhibiting eukaryotic cell growth, with the guanine nucleotides exhibiting stronger effects than cdiAMP. Mutations compromising mitochondrial function and chromatin remodeling show negative epistatic interactions with all three nucleotides. In contrast, certain mutations that cause defects in chromatin modification and ribosomal protein function show positive epistasis, alleviating growth inhibition by at least two of the three nucleotides. Uniquely, cdiGMP is lethal both to cells growing by respiration on acetate and to obligately fermentative petite mutants. cdiGMP is also synthetically lethal with the ribonucleotide reductase (RNR inhibitor hydroxyurea. Heterologous expression of the human ppGpp hydrolase Mesh1p prevented the accumulation of ppGpp in the engineered yeast and restored cell growth. Extensive in vivo interactions between bacterial signaling molecules and eukaryotic gene function occur, resulting in outcomes ranging from growth inhibition to death. cdiGMP functions through a mechanism that must be compensated by unhindered RNR activity or by functionally competent mitochondria. Mesh1p may be required for abrogating the damaging effects of ppGpp in human cells subjected to bacterial infection.

HIV protease inhibitors disrupt lipid metabolism by activating endoplasmic reticulum stress and inhibiting autophagy activity in adipocytes.

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Beth S Zha

Full Text Available HIV protease inhibitors (PI are core components of Highly Active Antiretroviral Therapy (HAART, the most effective treatment for HIV infection currently available. However, HIV PIs have now been linked to lipodystrophy and dyslipidemia, which are major risk factors for cardiovascular disease and metabolic syndrome. Our previous studies have shown that HIV PIs activate endoplasmic reticulum (ER stress and disrupt lipid metabolism in hepatocytes and macrophages. Yet, little is known on how HIV PIs disrupt lipid metabolism in adipocytes, a major cell type involved in the pathogenesis of metabolic syndrome.Cultured and primary mouse adipocytes and human adipocytes were used to examine the effect of frequently used HIV PIs in the clinic, lopinavir/ritonavir, on adipocyte differentiation and further identify the underlying molecular mechanism of HIV PI-induced dysregulation of lipid metabolism in adipocytes. The results indicated that lopinavir alone or in combination with ritonavir, significantly activated the ER stress response, inhibited cell differentiation, and induced cell apoptosis in adipocytes. In addition, HIV PI-induced ER stress was closely linked to inhibition of autophagy activity. We also identified through the use of primary adipocytes of CHOP(-/- mice that CHOP, the major transcriptional factor of the ER stress signaling pathway, is involved in lopinavir/ritonavir-induced inhibition of cell differentiation in adipocytes. In addition, lopinavir/ritonavir-induced ER stress appears to be associated with inhibition of autophagy activity in adipocytes.Activation of ER stress and impairment of autophagy activity are involved in HIV PI-induced dysregulation of lipid metabolism in adipocytes. The key components of ER stress and autophagy signaling pathways are potential therapeutic targets for HIV PI-induced metabolic side effects in HIV patients.

Alzheimer’s Pathogenesis and Its Link to the Mitochondrion

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C. Simoncini

2015-01-01

Full Text Available Alzheimer’s disease (AD is the most common form of dementia in the elderly. This neurodegenerative disorder is clinically characterized by impairment of cognitive functions and changes in behaviour and personality. The pathogenesis of AD is still unclear. Recent evidence supports some role of mitochondria dysfunction and oxidative stress in the development of the neurodegenerative process. In this review, we discuss the role of mitochondrial dysfunction in AD, focusing on the mechanisms that lead to mitochondrial impairment, oxidative stress, and neurodegeneration, a “vicious circle” that ends in dementia.

JAK-inhibitor tofacitinib suppresses interferon alfa production by plasmacytoid dendritic cells and inhibits arthrogenic and antiviral effects of interferon alfa.

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Boor, Patrick P C; de Ruiter, Petra E; Asmawidjaja, Patrick S; Lubberts, Erik; van der Laan, Luc J W; Kwekkeboom, Jaap

2017-10-01

Tofacitinib is an oral Janus kinase inhibitor that is effective for the treatment of rheumatoid arthritis and shows encouraging therapeutic effects in several other autoimmune diseases. A prominent adverse effect of tofacitinib therapy is the increased risk of viral infections. Despite its advanced stage of clinical development, the modes of action that mediate the beneficial and adverse effects of tofacitinib in autoimmune diseases remain unclear. Interferon alfa (IFNα) produced by plasmacytoid dendritic cells (PDCs) is critically involved in the pathogenesis of many systemic autoimmune diseases and in immunity to viral infections. Using in vitro culture models with human cells, we studied the effects of tofacitinib on PDC survival and IFNα production, and on arthrogenic and antiviral effects of IFNα. Tofacitinib inhibited the expression of antiapoptotic BCL-A1 and BCL-XL in human PDC and induced PDC apoptosis. TLR7 stimulation upregulated the levels of antiapoptotic Bcl-2 family members and prevented the induction of PDC apoptosis by tofacitinib. However, tofacitinib robustly inhibited the production of IFNα by toll like receptor-stimulated PDC. In addition, tofacitinib profoundly suppressed IFNα-induced upregulation of TLR3 on synovial fibroblasts, thereby inhibiting their cytokine and protease production in response to TLR3 ligation. Finally, tofacitinib counteracted the suppressive effects of IFNα on viral replication. Tofacitinib inhibits PDC survival and IFNα production and suppresses arthrogenic and antiviral effects of IFNα signaling. Inhibition of the IFNα pathway at 2 levels may contribute to the beneficial effects of tofacitinib in autoimmune diseases and explain the increased viral infection rates observed during tofacitinib treatment. Copyright © 2016 Elsevier Inc. All rights reserved.

Kaposi sarcoma herpesvirus pathogenesis

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Koch, Sandra; Schulz, Thomas F.

2017-01-01

Kaposi sarcoma herpesvirus (KSHV), taxonomical name human gammaherpesvirus 8, is a phylogenetically old human virus that co-evolved with human populations, but is now only common (seroprevalence greater than 10%) in sub-Saharan Africa, around the Mediterranean Sea, parts of South America and in a few ethnic communities. KSHV causes three human malignancies, Kaposi sarcoma, primary effusion lymphoma, and many cases of the plasmablastic form of multicentric Castleman's disease (MCD) as well as occasional cases of plasmablastic lymphoma arising from MCD; it has also been linked to rare cases of bone marrow failure and hepatitis. As it has colonized humans physiologically for many thousand years, cofactors are needed to allow it to unfold its pathogenic potential. In most cases, these include immune defects of genetic, iatrogenic or infectious origin, and inflammation appears to play an important role in disease development. Our much improved understanding of its life cycle and its role in pathogenesis should now allow us to develop new therapeutic strategies directed against key viral proteins or intracellular pathways that are crucial for virus replication or persistence. Likewise, its limited (for a herpesvirus) distribution and transmission should offer an opportunity for the development and use of a vaccine to prevent transmission. This article is part of the themed issue ‘Human oncogenic viruses’. PMID:28893942

The Gut Microbiome and HIV-1 Pathogenesis: A Two Way Street

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Dillon, Stephanie M.; Frank, Daniel N.; Wilson, Cara C.

2016-01-01

HIV-1 infection is associated with substantial damage to the gastrointestinal (GI) tract resulting in structural impairment of the epithelial barrier and a disruption of intestinal homeostasis. The accompanying translocation of microbial products and potentially microbes themselves from the lumen into systemic circulation has been linked to immune activation, inflammation, and HIV-1 disease progression. The importance of microbial translocation in the setting of HIV-1 infection has led to a recent focus on understanding how the communities of microbes that make up the intestinal microbiome are altered during HIV-1 infection and how they interact with mucosal immune cells to contribute to inflammation. This review details the dysbiotic intestinal communities associated with HIV-1 infection and their potential link to HIV-1 pathogenesis. We detail studies that begin to address the mechanisms driving microbiota-associated immune activation and inflammation and the various treatment strategies aimed at correcting dysbiosis and improving the overall health of HIV-1 infected individuals. Finally, we discuss how this relatively new field of research can advance to provide a more comprehensive understanding of the contribution of the gut microbiome to HIV-1 pathogenesis. PMID:27755100

Subclassification of fatty liver by its pathogenesis: cIEFing is believing.

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Byrne, Frances L; Hoehn, Kyle L

2016-05-01

Fatty liver, also termed hepatic steatosis or fatty liver disease, is a condition characterized by excess fat accumulation in the liver. Common causes of fatty liver include obesity, ageing, medications, genetic disorders, viral hepatitis, excess alcohol or toxins. This diversity in pathogenesis is matched by an equally diverse spectrum of consequences, whereby some individuals remain asymptomatic yet others progress through a series of inflammatory, fibrotic and metabolic disorders that can lead to liver failure, cancer or diabetes. Current treatment approaches for fatty liver do not differ by disease aetiology and primarily involve weight loss strategies or management of co-morbidities. In a recent paper published in this journal, Urasaki et al used capillary isoelectric focusing (cIEF) to create profiles of protein post-translational modifications that distinguish four different models of fatty liver in mice. Importantly, this new cIEF approach has the potential to provide rapid individualized diagnosis of fatty liver pathogenesis that may enable more accurate and personalized treatment strategies. Further testing and optimization of cIEF as a diagnostic screening tool in humans is warranted. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Pathogenesis of Nonalcoholic Steatohepatitis: Interactions between Liver Parenchymal and Nonparenchymal Cells

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Nancy Magee

2016-01-01

Full Text Available Nonalcoholic fatty liver disease (NAFLD is the most common type of chronic liver disease in the Western countries, affecting up to 25% of the general population and becoming a major health concern in both adults and children. NAFLD encompasses the entire spectrum of fatty liver disease in individuals without significant alcohol consumption, ranging from nonalcoholic fatty liver (NAFL to nonalcoholic steatohepatitis (NASH and cirrhosis. NASH is a manifestation of the metabolic syndrome and hepatic disorders with the presence of steatosis, hepatocyte injury (ballooning, inflammation, and, in some patients, progressive fibrosis leading to cirrhosis. The pathogenesis of NASH is a complex process and implicates cell interactions between liver parenchymal and nonparenchymal cells as well as crosstalk between various immune cell populations in liver. Lipotoxicity appears to be the central driver of hepatic cellular injury via oxidative stress and endoplasmic reticulum (ER stress. This review focuses on the contributions of hepatocytes and nonparenchymal cells to NASH, assessing their potential applications to the development of novel therapeutic agents. Currently, there are limited pharmacological treatments for NASH; therefore, an increased understanding of NASH pathogenesis is pertinent to improve disease interventions in the future.

Development and Validation of a Novel Dual Luciferase Reporter Gene Assay to Quantify Ebola Virus VP24 Inhibition of IFN Signaling

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Elisa Fanunza

2018-02-01

Full Text Available The interferon (IFN system is the first line of defense against viral infections. Evasion of IFN signaling by Ebola viral protein 24 (VP24 is a critical event in the pathogenesis of the infection and, hence, VP24 is a potential target for drug development. Since no drugs target VP24, the identification of molecules able to inhibit VP24, restoring and possibly enhancing the IFN response, is a goal of concern. Accordingly, we developed a dual signal firefly and Renilla luciferase cell-based drug screening assay able to quantify IFN-mediated induction of Interferon Stimulated Genes (ISGs and its inhibition by VP24. Human Embryonic Kidney 293T (HEK293T cells were transiently transfected with a luciferase reporter gene construct driven by the promoter of ISGs, Interferon-Stimulated Response Element (ISRE. Stimulation of cells with IFN-α activated the IFN cascade leading to the expression of ISRE. Cotransfection of cells with a plasmid expressing VP24 cloned from a virus isolated during the last 2014 outbreak led to the inhibition of ISRE transcription, quantified by a luminescent signal. To adapt this system to test a large number of compounds, we performed it in 96-well plates; optimized the assay analyzing different parameters; and validated the system by calculating the Z′- and Z-factor, which showed values of 0.62 and 0.53 for IFN-α stimulation assay and VP24 inhibition assay, respectively, indicative of robust assay performance.

Age-Related Macular Degeneration: Pathogenesis, Genetic Background, and the Role of Nutritional Supplements

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Marilita M. Moschos

2014-01-01

Full Text Available Age-related macular degeneration (ARMD is the leading cause of severe vision loss and blindness worldwide, mainly affecting people over 65 years old. Dry and wet ARDM are the main types of the disease, which seem to have a multifactorial background. The aim of this review is to summarize the mechanisms of ARMD pathogenesis and exhibit the role of diet and nutritional supplements in the onset and progression of the disease. Environmental factors, such as smoking, alcohol, and, diet appear to interact with mutations in nuclear and mitochondrial DNA, contributing to the pathogenesis of ARMD. Inflammatory mediators and oxidative stress, induced by the daily exposure of retina to high pressure of oxygen and light radiation, have been also associated with ARMD lesions. Other than medical and surgical therapies, nutritional supplements hold a significant role in the prevention and treatment of ARMD, eliminating the progression of macular degeneration.

Ammonia inhibits long-term potentiation via neurosteroid synthesis in hippocampal pyramidal neurons.

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Izumi, Y; Svrakic, N; O'Dell, K; Zorumski, C F

2013-03-13

Neurosteroids are a class of endogenous steroids synthesized in the brain that are believed to be involved in the pathogenesis of neuropsychiatric disorders and memory impairment. Ammonia impairs long-term potentiation (LTP), a synaptic model of learning, in the hippocampus, a brain region involved in memory acquisition. Although mechanisms underlying ammonia-mediated LTP inhibition are not fully understood, we previously found that the activation of N-methyl-d-aspartate receptors (NMDARs) is important. Based on this, we hypothesize that metabolic stressors, including hyperammonemia, promote untimely NMDAR activation and result in neural adaptations that include the synthesis of allopregnanolone (alloP) and other GABA-potentiating neurosteroids that dampen neuronal activity and impair LTP and memory formation. Using an antibody against 5α-reduced neurosteroids, we found that 100 μM ammonia acutely enhanced neurosteroid immunostaining in pyramidal neurons in the CA1 region of rat hippocampal slices. The enhanced staining was blocked by finasteride, a selective inhibitor of 5α-reductase, a key enzyme required for alloP synthesis. Finasteride also overcame LTP inhibition by 100 μM ammonia, as did picrotoxin, an inhibitor of GABA-A receptors. These results indicate that GABA-enhancing neurosteroids, synthesized locally within pyramidal neurons, contribute significantly to ammonia-mediated synaptic dysfunction. These results suggest that the manipulation of neurosteroid synthesis could provide a strategy to improve cognitive function in individuals with hyperammonemia. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

Pathogenesis of chronic pancreatitis: an evidence-based review of past theories and recent developments.

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Stevens, Tyler; Conwell, Darwin L; Zuccaro, Gregory

2004-11-01

In the past several decades, four prominent theories of chronic pancreatitis pathogenesis have emerged: the toxic-metabolic theory, the oxidative stress hypothesis, the stone and duct obstruction theory, and the necrosis-fibrosis hypothesis. Although these traditional theories are formulated based on compelling scientific observations, substantial contradictory data also exist for each. Furthermore, the basic premises of some of these theories are directly contradictory. Because of the recent scientific progress in the underlying genetic, cellular, and molecular pathophysiology, there have been substantial advances in the understanding of chronic pancreatitis pathogenesis. This paper will provide an evidence-based review and critique of the traditional pathogenic theories, followed by a discussion of the new advances in pancreatic fibrogenesis. Moreover, we will discuss plausible pathogenic sequences applied to each of the known etiologies.

Overview of the pathogenesis and treatment of chronic inflammatory demyelinating polyneuropathy with intravenous immunoglobulins

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Mohamed Mahdi-Rogers

2010-03-01

Full Text Available Mohamed Mahdi-Rogers, Yusuf A RajaballyNeuromuscular Clinic, Department of Neurology, University Hospitals of Leicester, Leicester, UKAbstract: Chronic inflammatory demyelinating polyneuropathy (CIDP is an acquired heterogeneous disorder of immune origin affecting the peripheral nerves, causing motor weakness and sensory symptoms and signs. The precise pathophysiology of CIDP remains uncertain although B and T cell mechanisms are believed to be implicated. Intravenous immunoglobulins (IVIg have been shown in a number of trials to be an effective treatment for CIDP. IVIg is thought to exert its immunomodulatory effects by affecting several components of the immune system including B-cells, T-cells, macrophages and complement. This article provides an overview of the pathogenesis of CIDP and of its treatment with IVIg.Keywords: chronic inflammatory demyelinating polyneuropathy, intravenous immunoglobulin, pathogenesis, treatment

Etiology and pathogenesis of antisperm antibody

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farhad Shahsavar

2011-06-01

Full Text Available Antisperm antibodies (ASA occur in men and women and may significantly impair fertility. In this case, the testis is an immunologically privileged site where germ cell antigens are protected from autoimmune attack. However, due to disruption of the blood-testis barrier occurring from testicular injury, or as a consequence of trauma to the epididymis or vas deferens many testicular proteins get autoantigenic during immunological challenges resulting in the formation of ASA in the blood serum, seminal plasma or located on the sperm membrane. ASA have also been reported to be associated with inflammation, cryptorchidism, varicocele and surgical intervention in the genital organs. ASA may interfere with different sperm functions, which are essential for the fertilization process.This review article will help to increase our understanding of the specific mechanisms that elicit the autoimmune response to sperm and of the pathogenesis of ASA that leads to an antibody-mediated infertility.

Role of the Lung Microbiome in the Pathogenesis of Chronic Obstructive Pulmonary Disease.

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Wang, Lei; Hao, Ke; Yang, Ting; Wang, Chen

2017-09-05

The development of culture-independent techniques for microbiological analysis shows that bronchial tree is not sterile in either healthy or chronic obstructive pulmonary disease (COPD) individuals. With the advance of sequencing technologies, lung microbiome has become a new frontier for pulmonary disease research, and such advance has led to better understanding of the lung microbiome in COPD. This review aimed to summarize the recent advances in lung microbiome, its relationships with COPD, and the possible mechanisms that microbiome contributed to COPD pathogenesis. Literature search was conducted using PubMed to collect all available studies concerning lung microbiome in COPD. The search terms were "microbiome" and "chronic obstructive pulmonary disease", or "microbiome" and "lung/pulmonary". The papers in English about lung microbiome or lung microbiome in COPD were selected, and the type of articles was not limited. The lung is a complex microbial ecosystem; the microbiome in lung is a collection of viable and nonviable microbiota (bacteria, viruses, and fungi) residing in the bronchial tree and parenchymal tissues, which is important for health. The following types of respiratory samples are often used to detect the lung microbiome: sputum, bronchial aspirate, bronchoalveolar lavage, and bronchial mucosa. Disordered bacterial microbiome is participated in pathogenesis of COPD; there are also dynamic changes in microbiota during COPD exacerbations. Lung microbiome may contribute to the pathogenesis of COPD by manipulating inflammatory and/or immune process. Normal lung microbiome could be useful for prophylactic or therapeutic management in COPD, and the changes of lung microbiome could also serve as biomarkers for the evaluation of COPD.

Significance of endothelial dysfunction in the pathogenesis of early and delayed radiation enteropathy

Institute of Scientific and Technical Information of China (English)

Junru Wang; Marjan Boerma; Qiang Fu; Martin Hauer-Jensen

2007-01-01

This review summarizes the current state of knowledge regarding the role of endothelial dysfunction in the pathogenesis of early and delayed intestinal radiation toxicity and discusses various endothelial-oriented interventions aimed at reducing the risk of radiation enteropathy. Studies published in the biomedical literature during the past four decades and cited in PubMed, as well as clinical and laboratory data from our own research program are reviewed. The risk of injury to normal tissues limits the cancer cure rates that can be achieved with radiation therapy. During treatment of abdominal and pelvic tumors, the intestine is frequently a major dose-limiting factor. Microvascular injury is a prominent feature of both early (inflammatory), as well as delayed (fibroproliferative) radiation injuries in the intestine and in many other normal tissues. Evidence from our and other laboratories suggests that endothelial dysfunction, notably a deficiency of endothelial thrombomodulin, plays a key role in the pathogenesis of these radiation responses. Deficient levels of thrombomodulin cause loss of vascular thromboresistance, excessive activation of cellular thrombin receptors by thrombin, and insufficient activation of protein C, a plasma protein with anticoagulant, anti-inflammatory, and cytoprotective properties. These changes are presumed to be critically involved in many aspects of early intestinal radiation toxicity and may sustain the fibroproliferative processes that lead to delayed intestinal dysfunction, fibrosis, and clinical complications. In conclusion, injury of vascular endothelium is important in the pathogenesis of the intestinal radiation response. Endothelial-oriented interventions are appealing strategies to prevent or treat normal tissue toxicity associated with radiation treatment of cancer.

Foodborne Campylobacter: Infections, Metabolism, Pathogenesis and Reservoirs

Directory of Open Access Journals (Sweden)

Sharon V. R. Epps

2013-11-01

Full Text Available Campylobacter species are a leading cause of bacterial-derived foodborne illnesses worldwide. The emergence of this bacterial group as a significant causative agent of human disease and their propensity to carry antibiotic resistance elements that allows them to resist antibacterial therapy make them a serious public health threat. Campylobacter jejuni and Campylobacter coli are considered to be the most important enteropathogens of this genus and their ability to colonize and survive in a wide variety of animal species and habitats make them extremely difficult to control. This article reviews the historical and emerging importance of this bacterial group and addresses aspects of the human infections they cause, their metabolism and pathogenesis, and their natural reservoirs in order to address the need for appropriate food safety regulations and interventions.

Pathogenesis of Graves' disease and therapeutic implications

International Nuclear Information System (INIS)

Seif, F.J.

1997-01-01

Graves' disease presents itself clinically mainly as hyperthyroidism and infiltrative ophthalmopathy and to a minimal extent also as dermopathy and acropachy. Autoimmune processes are the basic pathogenesis. Stimulating antibodies against the TSH receptor cause hyperthyroidism. Autoantibodies and autoreactive T lymphocytes against primarily thyroidal antigens cross-react with similar antigens of the eye muscles and orbital connective tissue, thus spreading the disease from the thyroid to the eyes. The therapeutic goal comprises not only the treatment of hyperthyroidism, but also the induction of a steady immuntolerance in order to minimize the irreversible damage to the eye. The therapeutic armamentarium is formed by antithyroid drugs, glucocorticoids, retrobulbar radition and thyroid ablation, either by nearly total thyroidectomy or by radioiodine. The different indications for both ablative procedures are discussed. (orig.) [de

Circulating microbial products and acute phase proteins as markers of pathogenesis in lymphatic filarial disease.

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R Anuradha

Full Text Available Lymphatic filariasis can be associated with development of serious pathology in the form of lymphedema, hydrocele, and elephantiasis in a subset of infected patients. Dysregulated host inflammatory responses leading to systemic immune activation are thought to play a central role in filarial disease pathogenesis. We measured the plasma levels of microbial translocation markers, acute phase proteins, and inflammatory cytokines in individuals with chronic filarial pathology with (CP Ag+ or without (CP Ag- active infection; with clinically asymptomatic infections (INF; and in those without infection (endemic normal [EN]. Comparisons between the two actively infected groups (CP Ag+ compared to INF and those without active infection (CP Ag- compared to EN were used preliminarily to identify markers of pathogenesis. Thereafter, we tested for group effects among all the four groups using linear models on the log transformed responses of the markers. Our data suggest that circulating levels of microbial translocation products (lipopolysaccharide and LPS-binding protein, acute phase proteins (haptoglobin and serum amyloid protein-A, and inflammatory cytokines (IL-1β, IL-12, and TNF-α are associated with pathogenesis of disease in lymphatic filarial infection and implicate an important role for circulating microbial products and acute phase proteins.

Procyanidins Mitigate Osteoarthritis Pathogenesis by, at Least in Part, Suppressing Vascular Endothelial Growth Factor Signaling

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Angela Wang

2016-12-01

Full Text Available Procyanidins are a family of plant metabolites that have been suggested to mitigate osteoarthritis pathogenesis in mice. However, the underlying mechanism is largely unknown. This study aimed to determine whether procyanidins mitigate traumatic injury-induced osteoarthritis (OA disease progression, and whether procyanidins exert a chondroprotective effect by, at least in part, suppressing vascular endothelial growth factor signaling. Procyanidins (extracts from pine bark, orally administered to mice subjected to surgery for destabilization of the medial meniscus, significantly slowed OA disease progression. Real-time polymerase chain reaction revealed that procyanidin treatment reduced expression of vascular endothelial growth factor and effectors in OA pathogenesis that are regulated by vascular endothelial growth factor. Procyanidin-suppressed vascular endothelial growth factor expression was correlated with reduced phosphorylation of vascular endothelial growth factor receptor 2 in human OA primary chondrocytes. Moreover, components of procyanidins, procyanidin B2 and procyanidin B3 exerted effects similar to those of total procyanidins in mitigating the OA-related gene expression profile in the primary culture of human OA chondrocytes in the presence of vascular endothelial growth factor. Together, these findings suggest procyanidins mitigate OA pathogenesis, which is mediated, at least in part, by suppressing vascular endothelial growth factor signaling.

The role of oxytocin in the pathogenesis and treatment of schizophrenia

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Jusiak Katarzyna

2017-12-01

Full Text Available Introduction: Until recently, oxytocin was mainly associated with the pathophysiology of childbirth and sexual functions, but lately this hormone has become the object of interest to psychiatry and psychology due to the significant influence of oxytocin on human behavior in the field of social and emotional functioning. Current scientific research focuses on the participation of oxytocin in the pathogenesis and therapy of mental disorders.

HIF-1α inhibition blocks the cross talk between multiple myeloma plasma cells and tumor microenvironment

Energy Technology Data Exchange (ETDEWEB)

Borsi, Enrica, E-mail: enrica.borsi2@unibo.it [Department of Experimental Diagnostic and Specialty Medicine (DIMES), “L. and A. Seràgnoli”, Bologna University School of Medicine, S. Orsola' s University Hospital (Italy); Perrone, Giulia [Fondazione IRCCS Istituto Nazionale dei Tumori, Hematology Department, Via Venezian 1, 20133 Milano (Italy); Terragna, Carolina; Martello, Marina; Zamagni, Elena; Tacchetti, Paola; Pantani, Lucia; Brioli, Annamaria; Dico, Angela Flores; Zannetti, Beatrice Anna; Rocchi, Serena; Cavo, Michele [Department of Experimental Diagnostic and Specialty Medicine (DIMES), “L. and A. Seràgnoli”, Bologna University School of Medicine, S. Orsola' s University Hospital (Italy)

2014-11-01

Multiple myeloma (MM) is a malignant disorder of post-germinal center B cells, characterized by the clonal proliferation of malignant plasma cells (PCs) within the bone marrow (BM). The reciprocal and complex interactions that take place between the different compartments of BM and the MM cells result in tumor growth, angiogenesis, bone disease, and drug resistance. Given the importance of the BM microenvironment in MM pathogenesis, we investigated the possible involvement of Hypoxia-Inducible transcription Factor-1 alpha (HIF-1α) in the PCs-bone marrow stromal cells interplay. To test this hypothesis, we used EZN-2968, a 3rd generation antisense oligonucleotide against HIF-1α, to inhibit HIF-1α functions. Herein, we provide evidence that the interaction between MM cells and BM stromal cells is drastically reduced upon HIF-1α down-modulation. Notably, we showed that upon exposure to HIF-1α inhibitor, neither the incubation with IL-6 nor the co-culture with BM stromal cells were able to revert the anti-proliferative effect induced by EZN-2968. Moreover, we observed a down-modulation of cytokine-induced signaling cascades and a reduction of MM cells adhesion capability to the extracellular matrix proteins in EZN-2968-treated samples. Taken together, these results strongly support the concept that HIF-1α plays a critical role in the interactions between bone BM cells and PCs in Multiple Myeloma. - Highlights: • HIF-1α inhibition induces a mild apoptotic cell death. • Down-modulation of cytokine-induced signaling cascades upon HIF-1α inhibition. • Reduced interaction between MM cells and BMSCs upon HIF-1α down-modulation. • Reduced PCs adhesion to the extracellular matrix protein induced by EZN-2968. • HIF-1α inhibition may be an attractive therapeutic strategy for Multiple Myeloma.

The role of intrinsic spinal mechanisms in the pathogenesis of adolescent idiopathic scoliosis

NARCIS (Netherlands)

Kouwenhoven, J.W.M.

2007-01-01

Despite numerous years of dedicated research into the origin of idiopathic scoliosis, the pathogenesis of this classic orthopaedic disorder has so far remained elusive. A striking feature of idiopathic scoliosis is the fact that it does not occur in vertebrates other than humans, despite many

The Pathogenesis of Lupus Nephritis

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Lech, Maciej

2013-01-01

Lupus nephritis is an immune complex GN that develops as a frequent complication of SLE. The pathogenesis of lupus nephritis involves a variety of pathogenic mechanisms. The extrarenal etiology of systemic lupus is based on multiple combinations of genetic variants that compromise those mechanisms normally assuring immune tolerance to nuclear autoantigens. This loss of tolerance becomes clinically detectable by the presence of antinuclear antibodies. In addition, nucleic acids released from netting or apoptotic neutrophils activate innate and adaptive immunity via viral nucleic acid-specific Toll-like receptors. Therefore, many clinical manifestations of systemic lupus resemble those of viral infection. In lupus, endogenous nuclear particles trigger IFN-α signaling just like viral particles during viral infection. As such, dendritic cells, T helper cells, B cells, and plasma cells all contribute to the aberrant polyclonal autoimmunity. The intrarenal etiology of lupus nephritis involves antibody binding to multiple intrarenal autoantigens rather than the deposition of circulating immune complexes. Tertiary lymphoid tissue formation and local antibody production add to intrarenal complement activation as renal immunopathology progresses. Here we provide an update on the pathogenic mechanisms that lead to lupus nephritis and provide the rationale for the latest and novel treatment strategies. PMID:23929771

Gemfibrozil, a lipid lowering drug, inhibits the activation of primary human microglia via peroxisome proliferator-activated receptor β.

Science.gov (United States)

Jana, Malabendu; Pahan, Kalipada

2012-08-01

Microglial activation participates in the pathogenesis of various neuroinflammatory and neurodegenerative diseases. However, mechanisms by which microglial activation could be controlled are poorly understood. Peroxisome proliferator-activated receptors (PPAR) are transcription factors belonging to the nuclear receptor super family with diverse effect. This study underlines the importance of PPARβ/δ in mediating the anti-inflammatory effect of gemfibrozil, an FDA-approved lipid-lowering drug, in primary human microglia. Bacterial lipopolysachharides (LPS) induced the expression of various proinflammatory molecules and upregulated the expression of microglial surface marker CD11b in human microglia. However, gemfibrozil markedly suppressed proinflammatory molecules and CD11b in LPS-stimulated microglia. Human microglia expressed PPAR-β and -γ, but not PPAR-α. Interestingly, either antisense knockdown of PPAR-β or antagonism of PPAR-β by a specific chemical antagonist abrogated gemfibrozil-mediated inhibition of microglial activation. On the other hand, blocking of PPAR-α and -γ had no effect on gemfibrozil-mediated anti-inflammatory effect in microglia. These results highlight the fact that gemfibrozil regulates microglial activation by inhibiting inflammatory gene expression in a PPAR-β dependent pathway and further reinforce its therapeutic application in several neuroinflammatory and neurodegenerative diseases.

A Novel Anti-Inflammatory Role for Ginkgolide B in Asthma via Inhibition of the ERK/MAPK Signaling Pathway

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Xiao Chu

2011-09-01

Full Text Available Ginkgolide B is an anti-inflammatory extract of Ginkgo biloba and has been used therapeutically. It is a known inhibitor of platelet activating factor (PAF, which is important in the pathogenesis of asthma. Here, a non-infectious mouse model of asthma is used to evaluate the anti-inflammatory capacity of ginkgolide B (GKB and characterize the interaction of GKB with the mitogen activated protein kinase (MAPK pathway. BALB/c mice that were sensitized and challenged to ovalbumin (OVA were treated with GKB (40 mg/kg one hour before they were challenged with OVA. Our study demonstrated that GKB may effectively inhibit the increase of T-helper 2 cytokines, such as interleukin (IL-5 and IL-13 in bronchoalveolar lavage fluid (BALF. Furthermore, the eosinophil count in BALF significantly decreased after treatment of GKB when compared with the OVA-challenged group. Histological studies demonstrated that GKB substantially inhibited OVA-induced eosinophilia in lung tissue and mucus hyper-secretion by goblet cells in the airway. These results suggest that ginkgolide B may be useful for the treatment of asthma and its efficacy is related to suppression of extracellular regulating kinase/MAPK pathway.

Pathogenesis of Hepatitis C Virus Infection in Tupaia belangeri▿†

Science.gov (United States)

Amako, Yutaka; Tsukiyama-Kohara, Kyoko; Katsume, Asao; Hirata, Yuichi; Sekiguchi, Satoshi; Tobita, Yoshimi; Hayashi, Yukiko; Hishima, Tsunekazu; Funata, Nobuaki; Yonekawa, Hiromichi; Kohara, Michinori

2010-01-01

The lack of a small-animal model has hampered the analysis of hepatitis C virus (HCV) pathogenesis. The tupaia (Tupaia belangeri), a tree shrew, has shown susceptibility to HCV infection and has been considered a possible candidate for a small experimental model of HCV infection. However, a longitudinal analysis of HCV-infected tupaias has yet to be described. Here, we provide an analysis of HCV pathogenesis during the course of infection in tupaias over a 3-year period. The animals were inoculated with hepatitis C patient serum HCR6 or viral particles reconstituted from full-length cDNA. In either case, inoculation caused mild hepatitis and intermittent viremia during the acute phase of infection. Histological analysis of infected livers revealed that HCV caused chronic hepatitis that worsened in a time-dependent manner. Liver steatosis, cirrhotic nodules, and accompanying tumorigenesis were also detected. To examine whether infectious virus particles were produced in tupaia livers, naive animals were inoculated with sera from HCV-infected tupaias, which had been confirmed positive for HCV RNA. As a result, the recipient animals also displayed mild hepatitis and intermittent viremia. Quasispecies were also observed in the NS5A region, signaling phylogenic lineage from the original inoculating sequence. Taken together, these data suggest that the tupaia is a practical animal model for experimental studies of HCV infection. PMID:19846521

Mechanisms that synergistically regulate η-secretase processing of APP and Aη-α protein levels: relevance to pathogenesis and treatment of Alzheimer's disease.

Science.gov (United States)

Ward, Joseph; Wang, Haizhi; Saunders, Aleister J; Tanzi, Rudolph E; Zhang, Can

2017-02-01

The pathophysiology of Alzheimer's disease (AD) is characterized by the formation of cerebral β-amyloid plaque from a small peptide amyloid-β (Aβ). Aβ is generated from the canonical amyloid-β precursor protein (APP) proteolysis pathway through β- and γ-secretases. Decreasing Aβ levels through targeting APP processing is a very promising direction in clinical trials for AD. A novel APP processing pathway was recently identified, in which η-secretase processing of APP occurs and results in the generation of the carboxy-terminal fragment-η (CTF-η or η-CTF) (Wang et al., 2015) and Aη-α peptide (Willem et al., 2015). η-Secretase processing of APP may be up-regulated by at least two mechanisms: either through inhibition of lysosomal-cathepsin degradation pathway (Wang et al., 2015) or through inhibition of BACE1 that competes with η-secretase cleavage of APP (Willem et al., 2015). A thorough characterization of η-processing of APP is critical for a better understanding of AD pathogenesis and insights into results of clinical trials of AD. Here we further investigated η-secretase processing of APP using well-characterized cell models of AD. We found that these two mechanisms act synergistically toward increasing η-secretase processing of APP and Aη-α levels. Furthermore, we evaluated the effects of several other known secretase modulators on η-processing of APP. The results of our study should advance the understanding of pathophysiology of AD, as well as enhance the knowledge in developing effective AD treatments or interventions related to η-secretase processing of APP.

Concepts on the pathogenesis of adolescent idiopathic scoliosis. Bone growth and mass, vertebral column, spinal cord, brain, skull, extra-spinal left-right skeletal length asymmetries, disproportions and molecular pathogenesis.

Science.gov (United States)

Burwell, R Geoffrey; Dangerfield, Peter H; Freeman, Brian J C

2008-01-01

There is no generally accepted scientific theory for the causes of adolescent idiopathic scoliosis (AIS). Encouraging advances thought to be related to AIS pathogenesis have recently been made in several fields including anthropometry of bone growth, bone mass, spinal growth modulation, extra-spinal left-right skeletal length asymmetries and disproportions, magnetic resonance imaging of vertebral column, spinal cord, brain, skull, and molecular pathogenesis. These advances are leading to the evaluation of new treatments including attempts at minimally invasive surgery on the spine and peri-apical ribs. Several concepts of AIS are outlined indicating their clinical applications but not their research potential. The concepts, by derivation morphological, molecular and mathematical, are addressed in 15 sections: 1) initiating and progressive factors; 2) relative anterior spinal overgrowth; 3) dorsal shear forces that create axial rotational instability; 4) rotational preconstraint; 5) uncoupled, or asynchronous, spinal neuro-osseous growth; 6) brain, nervous system and skull; 7) a novel neuro-osseous escalator concept based on a putative abnormality of two normal polarized processes namely, a) increasing skeletal dimensions, and b) the CNS body schema - both contained within a neuro-osseous timing of maturation (NOTOM) concept; 8) transverse plane pelvic rotation, skeletal asymmetries and developmental theory; 9) thoraco-spinal concept; 10) origin in contracture at the hips; 11) osteopenia; 12) melatonin deficiency; 13) systemic melatonin-signaling pathway dysfunction; 14) platelet calmodulin dysfunction; and 15) biomechanical spinal growth modulation. From these concepts, a collective model for AIS pathogenesis is formulated. The central concept of this model includes the body schema of the neural systems, widely-studied in adults, that control normal posture and coordinated movements with frames of reference in the posterior parietal cortex. The escalator concept

Prostate Cancer Diagnostics and Prognostics Based on Interphase Spatial Genome Positioning

Science.gov (United States)

2016-03-01

in lamin A/C and include Emery-Dreifuss muscular dystrophy (EDMD) and the premature aging disease Hutchison-Gilford progeria syndrome (HGPS) (Burke...P a g e Zhang Y, McCord RP, Ho YJ, Lajoie BR, Hildebrand DG, Simon AC, Becker MS, Alt FW, Dekker J (2012) Spatial organization of the mouse...diseases characterized by mutations in lamin A/C, and includes Emery-Dreifuss 483 muscular dystrophy and the premature aging disease Hutchinson-Gilford

Andrographolide Inhibits Oxidized LDL-Induced Cholesterol Accumulation and Foam Cell Formation in Macrophages.

Science.gov (United States)

Lin, Hung-Chih; Lii, Chong-Kuei; Chen, Hui-Chun; Lin, Ai-Hsuan; Yang, Ya-Chen; Chen, Haw-Wen

2018-01-01

oxLDL is involved in the pathogenesis of atherosclerotic lesions through cholesterol accumulation in macrophage foam cells. Andrographolide, the bioactive component of Andrographis paniculata, possesses several biological activities such as anti-inflammatory, anti-oxidant, and anticancer functions. Scavenger receptors (SRs), including class A SR (SR-A) and CD36, are responsible for the internalization of oxLDL. In contrast, receptors for reverse cholesterol transport, including ABCA1 and ABCG1, mediate the efflux of cholesterol from macrophage foam cells. Transcription factor liver X receptor [Formula: see text] (LXR[Formula: see text] plays a key role in lipid metabolism and inflammation as well as in the regulation of ABCA1 and ABCG1 expression. Because of the contribution of inflammation to macrophage foam cell formation and the potent anti-inflammatory activity of andrographolide, we hypothesized that andrographolide might inhibit oxLDL-induced macrophage foam cell formation. The results showed that andrographolide reduced oxLDL-induced lipid accumulation in macrophage foam cells. Andrographolide decreased the mRNA and protein expression of CD36 by inducing the degradation of CD36 mRNA; however, andrographolide had no effect on SR-A expression. In contrast, andrographolide increased the mRNA and protein expression of ABCA1 and ABCG1, which were dependent on LXR[Formula: see text]. Andrographolide enhanced LXR[Formula: see text] nuclear translocation and DNA binding activity. Treatment with the LXR[Formula: see text] antagonist GGPP and transfection with LXR[Formula: see text] siRNA reversed the ability of andrographolide to stimulate ABCA1 and ABCG1 protein expression. In conclusion, inhibition of CD36-mediated oxLDL uptake and induction of ABCA1- and ABCG1-dependent cholesterol efflux are two working mechanisms by which andrographolide inhibits macrophage foam cell formation, which suggests that andrographolide could be a potential candidate to prevent

A Chimeric Peptide Composed of a Dermaseptin Derivative and an RNA III-Inhibiting Peptide Prevents Graft-Associated Infections by Antibiotic-Resistant Staphylococci

Science.gov (United States)

Balaban, Naomi; Gov, Yael; Giacometti, Andrea; Cirioni, Oscar; Ghiselli, Roberto; Mocchegiani, Federico; Orlando, Fiorenza; D'Amato, Giuseppina; Saba, Vittorio; Scalise, Giorgio; Bernes, Sabina; Mor, Amram

2004-01-01

Staphylococcal bacteria are a prevalent cause of infections associated with foreign bodies and indwelling medical devices. Bacteria are capable of escaping antibiotic treatment through encapsulation into biofilms. RNA III-inhibiting peptide (RIP) is a heptapeptide that inhibits staphylococcal biofilm formation by obstructing quorum-sensing mechanisms. K4-S4(1-13)a is a 13-residue dermaseptin derivative (DD13) believed to kill bacteria via membrane disruption. We tested each of these peptides as well as a hybrid construct, DD13-RIP, for their ability to inhibit bacterial proliferation and suppress quorum sensing in vitro and for their efficacy in preventing staphylococcal infection in a rat graft infection model with methicillin-resistant Staphylococcus aureus (MRSA) or S. epidermidis (MRSE). In vitro, proliferation assays demonstrated that RIP had no inhibitory effect, while DD13-RIP and DD13 were equally effective, and that the chimeric peptide but not DD13 was slightly more effective than RIP in inhibiting RNA III synthesis, a regulatory RNA molecule important for staphylococcal pathogenesis. In vivo, the three peptides reduced graft-associated bacterial load in a dose-dependent manner, but the hybrid peptide was most potent in totally preventing staphylococcal infections at the lowest dose. In addition, each of the peptides acted synergistically with antibiotics. The data indicate that RIP and DD13 act in synergy by attacking bacteria simultaneously by two different mechanisms. Such a chimeric peptide may be useful for coating medical devices to prevent drug-resistant staphylococcal infections. PMID:15215107

Ventriculoperitoneal shunt-related infections caused by Staphylococcus epidermidis: pathogenesis and implications for treatment.

LENUS (Irish Health Repository)

Stevens, Niall T

2012-12-01

The insertion of medical devices, such as intraventricular shunts, is often complicated by infection leading to ventriculitis. Frequently, such infections result from colonisation and subsequent biofilm formation on the surfaces of the shunts by Staphylococcus epidermidis. The pathogenesis of neurosurgical shunt-related infection is complex with interactions between the pathogen, the device and the unique local immunological environment of the central nervous system (CNS). An ability to form biofilm, the main virulence determinant of Staphylococcus epidermidis, facilitates protection of the organism from the host defences while still initiating an immunological response. The presence of the blood brain barrier (BBB) and the biofilm itself also complicates treatment, which presents many challenges when managing shunt infections. A greater understanding of the interplay between S. epidermidis and the CNS could potentially improve the diagnosis, treatment and management of such infections. This review describes the pathogenesis, treatment and implications of S. epidermidis ventriculoperitoneal shunt-related infections, concentrating on recent research and the implications for treatment.

Vibrio parahaemolyticus: A Review on the Pathogenesis, Prevalence and Advance Molecular Identification Techniques

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Vengadesh eLetchumanan

2014-12-01

Full Text Available Vibrio parahaemolyticus is a Gram-negative halophilic bacterium that is found in estuarine, marine and coastal environments. Vibrio parahaemolyticus is the leading causal agent of human acute gastroenteritis following the consumption of raw, undercooked or mishandled marine products. In rare cases, Vibrio parahaemolyticus causes wound infection, ear infection or septicaemia in individuals with pre-existing medical conditions. Vibrio parahaemolyticus has two hemolysins virulence factors that are thermostable direct hemolysin (tdh-a pore-forming protein that contributes to the invasiveness of the bacterium in humans, and TDH-related hemolysin (trh, which plays a similar role as thermostable direct hemolysin (tdh in the disease pathogenesis. In addition, the bacterium is also encodes for adhesions and type III secretion systems (T3SS1 and T3SS2 to ensure its survival in the environment. This review aims at discussing the Vibrio parahemolyticus growth and characteristics, pathogenesis, prevalence and advances in molecular identification techniques.

Basal Cell Carcinoma: Pathogenesis, Epidemiology, Clinical Features, Diagnosis, Histopathology, and Management

Science.gov (United States)

Marzuka, Alexander G.; Book, Samuel E.

2015-01-01

Basal cell carcinoma (BCC) is the most common malignancy. Exposure to sunlight is the most important risk factor. Most, if not all, cases of BCC demonstrate overactive Hedgehog signaling. A variety of treatment modalities exist and are selected based on recurrence risk, importance of tissue preservation, patient preference, and extent of disease. The pathogenesis, epidemiology, clinical features, diagnosis, histopathology, and management of BCC will be discussed in this review. PMID:26029015

Implication of microRNAs in the Pathogenesis of MDS

Science.gov (United States)

Fang, Jing; Varney, Melinda; Starczynowski, Daniel T.

2016-01-01

MicroRNAs (miRNAs) are significant regulators of human hematopoietic stem cells (HSC), and their deregulation contributes to hematological malignancies. Myelodysplastic syndromes (MDS) represent a spectrum of hematological disorders characterized by dysfunctional HSC, ineffective blood cell production, progressive marrow failure, and an increased risk of developing acute myeloid leukemia (AML). Although miRNAs have been primarily studied in AML, only recently have similar studies been performed on MDS. In this review, we describe the normal function and expression of miRNAs in human HSC, and describe mounting evidence that deregulation of miRNAs contributes to the pathogenesis of MDS. PMID:22571695

The inhibition of cAMP-dependent protein kinase by full-length hepatitis C virus NS3/4A complex is due to ATP hydrolysis.

Science.gov (United States)

Aoubala, M; Holt, J; Clegg, R A; Rowlands, D J; Harris, M

2001-07-01

Hepatitis C virus (HCV) is an important cause of chronic liver disease, but the molecular mechanisms of viral pathogenesis remain to be established. The HCV non-structural protein NS3 complexes with NS4A and has three enzymatic activities: a proteinase and a helicase/NTPase. Recently, catalytically inactive NS3 fragments containing an arginine-rich motif have been reported to interact with, and inhibit, the catalytic subunit of cAMP-dependent protein kinase (PKA C-subunit). Here we demonstrate that full-length, catalytically active NS3/4A, purified from recombinant baculovirus-infected insect cells, is also able to inhibit PKA C-subunit in vitro. This inhibition was abrogated by mutation of either the arginine-rich motif or the conserved helicase motif II, both of which also abolished NTPase activity. As PKA C-subunit inhibition was also enhanced by poly(U) (an activator of NS3 NTPase activity), we hypothesized that PKA C-subunit inhibition could be due to NS3/4A-mediated ATP hydrolysis. This was confirmed by experiments in which a constant ATP concentration was maintained by addition of an ATP regeneration system--under these conditions PKA C-subunit inhibition was not observed. Interestingly, the mutations also abrogated the ability of wild-type NS3/4A to inhibit the PKA-regulated transcription factor CREB in transiently transfected hepatoma cells. Our data are thus not consistent with the previously proposed model in which the arginine-rich motif of NS3 was suggested to act as a pseudosubstrate inhibitor of PKA C-subunit. However, in vivo effects of NS3/4A suggest that ATPase activity may play a role in viral pathology in the infected liver.

Reciprocal products of chromosomal translocations in human cancer pathogenesis: key players or innocent bystanders?

Science.gov (United States)

Rego, Eduardo M; Pandolfi, Pier Paolo

2002-08-01

Chromosomal translocations are frequently involved in the pathogenesis of leukemias, lymphomas and sarcomas. They can lead to aberrant expression of oncogenes or the generation of chimeric proteins. Classically, one of the products is thought to be oncogenic. For example, in acute promyelocytic leukaemia (APL), reciprocal chromosomal translocations involving the retinoic acid receptor alpha (RARalpha) gene lead to the formation of two fusion genes: X-RARalpha and RARalpha-X (where X is the alternative RARalpha fusion partner: PML, PLZF, NPM, NuMA and STAT 5b). The X-RARalpha fusion protein is indeed oncogenic. However, recent data indicate that the RARalpha-X product is also critical in determining the biological features of this leukemia. Here, we review the current knowledge on the role of reciprocal products in cancer pathogenesis, and highlight how their expression might impact on the biology of their respective tumour types.

Positron emission tomography measurement of brain MAO-B inhibition in patients with Alzheimer's disease and elderly controls after oral administration of sembragiline

Energy Technology Data Exchange (ETDEWEB)

Sturm, Stefan [Roche Pharmaceutical Research and Early Development, Roche Innovation Center Basel, Basel (Switzerland); F. Hoffmann-La Roche Ltd, Basel (Switzerland); Forsberg, Anton; Stenkrona, Per; Varrone, Andrea; Fazio, Patrik; Nakao, Ryuji; Halldin, Christer [Karolinska Institutet, Department of Clinical Neuroscience, Centre for Psychiatric Research, Stockholm (Sweden); Nave, Stephane; Jamois, Candice; Ricci, Benedicte [Roche Pharmaceutical Research and Early Development, Roche Innovation Center Basel, Basel (Switzerland); Seneca, Nicholas [AstraZeneca Translational Science Center, Stockholm (Sweden); Comley, Robert A. [AbbVie, North Chicago, IL (United States); Ejduk, Zbigniew [Miedzyleski Specialistic Hospital, Internal Disease and Gastroenterology, Warsaw (Poland); Al-Tawil, Nabil [Karolinska University Hospital, Karolinska Trial Alliance Phase 1 Unit, Stockholm (Sweden); Akenine, Ulrika; Andreasen, Niels [Karolinska University Hospital, Karolinska Institutet Alzheimer Disease Research Centre and Clinical Trial Unit, Geriatric Clinic, Huddinge (Sweden)

2017-03-15

In Alzheimer's disease (AD), increased metabolism of monoamines by monoamine oxidase type B (MAO-B) leads to the production of toxic reactive oxygen species (ROS), which are thought to contribute to disease pathogenesis. Inhibition of the MAO-B enzyme may restore brain levels of monoaminergic neurotransmitters, reduce the formation of toxic ROS and reduce neuroinflammation (reactive astrocytosis), potentially leading to neuroprotection. Sembragiline (also referred as RO4602522, RG1577 and EVT 302 in previous communications) is a potent, selective and reversible inhibitor of MAO-B developed as a potential treatment for AD. This study assessed the relationship between plasma concentration of sembragiline and brain MAO-B inhibition in patients with AD and in healthy elderly control (EC) subjects. Positron emission tomography (PET) scans using [{sup 11}C]-{sub L}-deprenyl-D{sub 2} radiotracer were performed in ten patients with AD and six EC subjects, who received sembragiline each day for 6-15 days. At steady state, the relationship between sembragiline plasma concentration and MAO-B inhibition resulted in an E{sub max} of ∝80-90 % across brain regions of interest and in an EC{sub 50} of 1-2 ng/mL. Data in patients with AD and EC subjects showed that near-maximal inhibition of brain MAO-B was achieved with 1 mg sembragiline daily, regardless of the population, whereas lower doses resulted in lower and variable brain MAO-B inhibition. This PET study confirmed that daily treatment of at least 1 mg sembragiline resulted in near-maximal inhibition of brain MAO-B enzyme in patients with AD. (orig.)

The role of arterial vascularity in pathogenesis of infected pseudoarthrosis of the lower leg

International Nuclear Information System (INIS)

Konarski, K.

1993-01-01

A series of 250 femoral arteriographies performed in patients with leg pseudoarthrosis served to asses condition of arteries of the extremity. It was found that vascular injuries contribute significantly to pathogenesis of union disorders in lower leg fractures. (author)

Porcine reproductive and respiratory syndrome virus (PRRSV): pathogenesis and interaction with the immune System

Science.gov (United States)

This review addresses important issues of porcine reproductive and respiratory syndrome virus (PRRSV) infection, immunity, pathogenesis and control. Worldwide PRRS is the most economically important infectious disease of pigs. We highlight the latest information on viral genome structure, pathogenic...

Innate immunity in the pathogenesis of psoriasis.

LENUS (Irish Health Repository)

Sweeney, Cheryl M

2011-12-01

Psoriasis is a common, immune-mediated inflammatory skin disorder. T helper(h)1 and Th17 lymphocytes contribute to the pathogenesis of psoriasis through the release of inflammatory cytokines that promote further recruitment of immune cells, keratinocyte proliferation and sustained inflammation. The innate immune system is the first line of defence against infection and plays a crucial role in the initiation of the adaptive immune response. The presence of innate immune cells and their products in psoriatic skin plaques suggests a role for innate immunity in this disease. In addition, the innate immune system can direct the development of pathogenic Th cells in psoriasis. In this article, we will summarise the role of the innate immune system in psoriasis with particular emphasis on the role of cytokines, signalling pathways and cells of the innate immune system.

Pathogenesis could be one of the anti-cheating mechanisms for Pseudomonas aeruginosa society.

Science.gov (United States)

Huang, Zhengwei; Jiang, Yuntao; Liang, Jingping

2011-02-01

Pseudomonas aeruginosa is the major pathogen of chronic lung infections in individuals with cystic fibrosis (CF). Traditionally, it has been regarded as living in planktonic form, and as being able to perform only simple physiological activities. Recent studies in biofilm infections in CF patients, however, show that P. aeruginosa can perform many social behaviors, like cooperation and cheating. Based on the theory of "survival of the fittest", it may be presumed that every individual will take advantage of cheating instead of cooperation to increase its fitness, at the cost of group survival. In reality, however, a bacterial society can remain stable, even though cheaters arise frequently in the population. It is therefore possible that there are anti-cheating mechanisms in a bacterial society. The cheaters of P. aeruginosa will cause the loss or the decrease of the pathogenesis of the microorganism in the cystic fibrosis host. These defects in pathogenesis will be disadvantageous to bacterial colonization and compromise the resistance to host immunity. We therefore propose the hypothesis that the pathogenesis in cystic fibrosis lung infections could be one of the anti-cheating mechanisms that contribute to the hidden costs of the cheater strains. To test this hypothesis, we designed an experiment in an animal model of CF. If this hypothesis can be confirmed, it will illustrate that nontrivial analogies exist between microbial social behaviors and the social traits that are observed in the more traditional model systems for sociobiology. This will not only provide a genetic model for sociobiology research, but also cast light on the social control of chronic bacterial infections. Copyright © 2010. Published by Elsevier Ltd.

Pharmacogenomic and clinical data link non-pharmacokinetic metabolic dysregulation to drug side effect pathogenesis

DEFF Research Database (Denmark)

Zielinski, Daniel C.; Filipp, F. V.; Bordbar, A.

2015-01-01

Drug side effects cause a significant clinical and economic burden. However, mechanisms of drug action underlying side effect pathogenesis remain largely unknown. Here, we integrate pharmacogenomic and clinical data with a human metabolic network and find that non-pharmacokinetic metabolic pathways...

The Role of Intracellular Organisms in the Pathogenesis of Inflammatory Arthritis

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Animesh Singh

2014-01-01

Full Text Available Inflammatory arthritis is a condition which is characterised by recurrent episodes of joint pain and swelling. It encompasses a spectrum of disorders ranging from rheumatoid arthritis to ankylosing spondylitis. In these conditions, for reasons that are poorly understood, the immune system raises an inflammatory response within the joint space. In some cases, autoantigens have been identified (e.g., anticitrullinated peptides in rheumatoid arthritis, but the absence of these, in the seronegative arthritides, for example, raises question as to the underlying pathogenesis. Interest has, therefore, turned to host-pathogen interactions and whether aberrant immune responses to these could explain the development of arthritis. This has been most widely studied in reactive arthritis (ReA, where an infectious episode precedes the development of the joint symptoms. In this review, we present the evidence for the role of host-bacterial interactions in the pathogenesis of joint inflammation with particular emphasis on ReA. We discuss a range of possible mechanisms including molecular mimicry, persistent low grade infections, and abnormal host responses to common bacterial causes of reactive arthritis as well as discussing some of the clinical challenges that we face in making the diagnosis and in treatment of persistent symptoms.

Advances in the microbial etiology and pathogenesis of early childhood caries

Science.gov (United States)

Hajishengallis, Evlambia; Parsaei, Yassmin; Klein, Marlise I.; Koo, Hyun

2016-01-01

Early childhood caries (ECC) is one of the most prevalent infectious diseases affecting children worldwide. ECC is an aggressive form of dental caries, which left untreated, can result in rapid and extensive cavitation in teeth (rampant caries) that is painful and costly to treat. Furthermore, it affects mostly children from impoverished background, and thus constitutes a major challenge in public health. The disease is a prime example of the consequences arising from complex, dynamic interactions between microorganisms, host and diet, leading to the establishment of highly pathogenic (cariogenic) biofilms. To date, there are no effective methods to identify those at risk of developing ECC or control the disease in affected children. Recent advances in deep-sequencing technologies, novel imaging methods and (meta)proteomics-metabolomics approaches provide an unparalleled potential to reveal new insights to illuminate our current understanding about the etiology and pathogenesis of the disease. In this concise review, we provide a broader perspective about the etiology and pathogenesis of ECC based on previous and current knowledge on biofilm matrix, microbial diversity and host-microbe interactions which could have direct implications for developing new approaches for improved risk assessment and prevention of this devastating and costly childhood health condition. PMID:26714612

MicroRNAs as Active Players in the Pathogenesis of Multiple Sclerosis

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Elio Scarpini

2012-10-01

Full Text Available MicroRNAs (miRNAs are a recently discovered group of small noncoding RNAs that regulate gene expression post-transcriptionally. They are highly expressed in cells of the immune system, as well as in the central nervous system, and they are deregulated in various neurological disorders. Emerging evidence underlines an involvement of miRNAs in the pathogenesis of Multiple Sclerosis (MS. A number of miRNAs have been found to be dysregulated in blood cells from MS patients, in brain lesions, as well as in biological fluids such as serum and plasma. Despite miRNA altered expression likely showing a high tissue specificity, some profile similarities could be observed for certain miRNAs such as miR-326—such as upregulation in both active lesions and blood—though not for others such as miR-323, which demonstrated upregulation in whole blood, active brain lesions, and T-reg cells, but not in the serum of MS patients. In this review, the possible role of miRNAs in MS pathogenesis will be discussed according to all the available literature, with a particular emphasis on the possibility of considering extracellular miRNAs as a new source for both biomarker identification and therapeutic target discovery.

MicroRNAs as Active Players in the Pathogenesis of Multiple Sclerosis

Science.gov (United States)

Fenoglio, Chiara; Ridolfi, Elisa; Galimberti, Daniela; Scarpini, Elio

2012-01-01

MicroRNAs (miRNAs) are a recently discovered group of small noncoding RNAs that regulate gene expression post-transcriptionally. They are highly expressed in cells of the immune system, as well as in the central nervous system, and they are deregulated in various neurological disorders. Emerging evidence underlines an involvement of miRNAs in the pathogenesis of Multiple Sclerosis (MS). A number of miRNAs have been found to be dysregulated in blood cells from MS patients, in brain lesions, as well as in biological fluids such as serum and plasma. Despite miRNA altered expression likely showing a high tissue specificity, some profile similarities could be observed for certain miRNAs such as miR-326—such as upregulation in both active lesions and blood—though not for others such as miR-323, which demonstrated upregulation in whole blood, active brain lesions, and T-reg cells, but not in the serum of MS patients. In this review, the possible role of miRNAs in MS pathogenesis will be discussed according to all the available literature, with a particular emphasis on the possibility of considering extracellular miRNAs as a new source for both biomarker identification and therapeutic target discovery. PMID:23202949

Pathogenesis of Lafora Disease: Transition of Soluble Glycogen to Insoluble Polyglucosan.

Science.gov (United States)

Sullivan, Mitchell A; Nitschke, Silvia; Steup, Martin; Minassian, Berge A; Nitschke, Felix

2017-08-11

Lafora disease (LD, OMIM #254780) is a rare, recessively inherited neurodegenerative disease with adolescent onset, resulting in progressive myoclonus epilepsy which is fatal usually within ten years of symptom onset. The disease is caused by loss-of-function mutations in either of the two genes EPM2A (laforin) or EPM2B (malin). It characteristically involves the accumulation of insoluble glycogen-derived particles, named Lafora bodies (LBs), which are considered neurotoxic and causative of the disease. The pathogenesis of LD is therefore centred on the question of how insoluble LBs emerge from soluble glycogen. Recent data clearly show that an abnormal glycogen chain length distribution, but neither hyperphosphorylation nor impairment of general autophagy, strictly correlates with glycogen accumulation and the presence of LBs. This review summarizes results obtained with patients, mouse models, and cell lines and consolidates apparent paradoxes in the LD literature. Based on the growing body of evidence, it proposes that LD is predominantly caused by an impairment in chain-length regulation affecting only a small proportion of the cellular glycogen. A better grasp of LD pathogenesis will further develop our understanding of glycogen metabolism and structure. It will also facilitate the development of clinical interventions that appropriately target the underlying cause of LD.

Vanillin Protects Dopaminergic Neurons against Inflammation-Mediated Cell Death by Inhibiting ERK1/2, P38 and the NF-κB Signaling Pathway.

Science.gov (United States)

Yan, Xuan; Liu, Dian-Feng; Zhang, Xiang-Yang; Liu, Dong; Xu, Shi-Yao; Chen, Guang-Xin; Huang, Bing-Xu; Ren, Wen-Zhi; Wang, Wei; Fu, Shou-Peng; Liu, Ju-Xiong

2017-02-12

Neuroinflammation plays a very important role in the pathogenesis of Parkinson's disease (PD). After activation, microglia produce pro-inflammatory mediators that damage surrounding neurons. Consequently, the inhibition of microglial activation might represent a new therapeutic approach of PD. Vanillin has been shown to protect dopaminergic neurons, but the mechanism is still unclear. Herein, we further study the underlying mechanisms in lipopolysaccharide (LPS)-induced PD models. In vivo, we firstly established rat models of PD by unilateral injection of LPS into substantia nigra (SN), and then examined the role of vanillin in motor dysfunction, microglial activation and degeneration of dopaminergic neurons. In vitro, murine microglial BV-2 cells were treated with vanillin prior to the incubation of LPS, and then the inflammatory responses and the related signaling pathways were analyzed. The in vivo results showed that vanillin markedly improved the motor dysfunction, suppressed degeneration of dopaminergic neurons and inhibited microglial over-activation induced by LPS intranigral injection. The in vitro studies demonstrated that vanillin reduces LPS-induced expression of inducible nitric oxide (iNOS), cyclooxygenase-2 (COX-2), IL-1β, and IL-6 through regulating ERK1/2, p38 and NF-κB signaling. Collectively, these data indicated that vanillin has a role in protecting dopaminergic neurons via inhibiting inflammatory activation.

The HBZ gene, a key player in HTLV-1 pathogenesis

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Green Patrick L

2009-08-01

Full Text Available Abstract Human T-cell leukemia virus type 1 (HTLV-1 causes adult T-cell leukemia/lymphoma (ATL and is also associated with a variety of lymphocyte-mediated diseases. The HTLV-1 basic leucine zipper (HBZ gene, found to be consistently expressed in ATL, has recently been the subject of intensive research efforts. In this review, we summarize recent findings about HBZ and discuss its roles and functions not only in the virus life cycle, but also in HTLV-1 disease pathogenesis.

Pulmonary capillary hemangiomatosis: a focus on the EIF2AK4 mutation in onset and pathogenesis

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Ma L

2015-08-01

Full Text Available Lijiang Ma,1,* Ruijun Bao2,*1Department of Pediatrics and Medicine, Division of Molecular Genetics, Columbia University Medical Center, New York, NY, 2The Children's IBD Center, Mount Sinai Hospital, New York, NY, USA *These authors contributed equally to this work Abstract: Pulmonary capillary hemangiomatosis (PCH is a pulmonary vascular disease that mainly affects small capillaries in the lung, and is often misdiagnosed as pulmonary arterial hypertension or pulmonary veno-occlusive disease due to similarities in their clinical presentations, prognosis, and management. In patients who are symptomatic, there is a high mortality rate with median survival of 3 years after diagnosis. Both idiopathic and familial PCH cases are being reported, indicating there is genetic component in disease etiology. Mutations in the eukaryotic translation initiation factor 2α kinase 4 (EIF2AK4 gene were identified in familial and idiopathic PCH cases, suggesting EIF2AK4 is a genetic risk factor for PCH. EIF2AK4 mutations were identified in 100% (6/6 of autosomal recessively inherited familial PCH and 20% (2/10 of sporadic PCH cases. EIF2AK4 is a member of serine/threonine kinases. It downregulates protein synthesis in response to a variety of cellular stress such as hypoxia, viral infection, and amino acid deprivation. Bone morphogenetic protein receptor 2 (BMPR2 is a major genetic risk factor in pulmonary arterial hypertension and EIF2AK4 potentially connects with BMPR2 to cause PCH. L-Arginine is substrate of nitric oxide synthase, and L-arginine is depleted during the production of nitric oxide, which may activate EIF2AK4 to inhibit protein synthesis and negatively regulate vasculogenesis. Mammalian target of rapamycin and EIF2α kinase are two major pathways for translational regulation. Mutant EIF2AK4 could promote proliferation of small pulmonary arteries by crosstalk with mammalian targets of the rapamycin signaling pathway. EIF2AK4 may regulate

Sustained NFκB inhibition improves insulin sensitivity but is detrimental to muscle health.

Science.gov (United States)

Zhang, Ning; Valentine, Joseph M; Zhou, You; Li, Mengyao E; Zhang, Yiqiang; Bhattacharya, Arunabh; Walsh, Michael E; Fischer, Katherine E; Austad, Steven N; Osmulski, Pawel; Gaczynska, Maria; Shoelson, Steven E; Van Remmen, Holly; Chen, Hung I; Chen, Yidong; Liang, Hanyu; Musi, Nicolas

2017-08-01

Older adults universally suffer from sarcopenia and approximately 60-70% are diabetic or prediabetic. Nonetheless, the mechanisms underlying these aging-related metabolic disorders are unknown. NFκB has been implicated in the pathogenesis of several aging-related pathologies including sarcopenia and type 2 diabetes and has been proposed as a target against them. NFκB also is thought to mediate muscle wasting seen with disuse, denervation, and some systemic diseases (e.g., cancer, sepsis). We tested the hypothesis that lifelong inhibition of the classical NFκB pathway would protect against aging-related sarcopenia and insulin resistance. Aged mice with muscle-specific overexpression of a super-repressor IκBα mutant (MISR) were protected from insulin resistance. However, MISR mice were not protected from sarcopenia; to the contrary, these mice had decreases in muscle mass and strength compared to wild-type mice. In MISR mice, NFκB suppression also led to an increase in proteasome activity and alterations in several genes and pathways involved in muscle growth and atrophy (e.g., myostatin). We conclude that the mechanism behind aging-induced sarcopenia is NFκB independent and differs from muscle wasting due to pathologic conditions. Our findings also indicate that, while suppressing NFκB improves insulin sensitivity in aged mice, this transcription factor is important for normal muscle mass maintenance and its sustained inhibition is detrimental to muscle function. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Proactive modulation of long-interval intracortical inhibition during response inhibition

Science.gov (United States)

Cowie, Matthew J.; MacDonald, Hayley J.; Cirillo, John

2016-01-01

Daily activities often require sudden cancellation of preplanned movement, termed response inhibition. When only a subcomponent of a whole response must be suppressed (required here on Partial trials), the ensuing component is markedly delayed. The neural mechanisms underlying partial response inhibition remain unclear. We hypothesized that Partial trials would be associated with nonselective corticomotor suppression and that GABAB receptor-mediated inhibition within primary motor cortex might be responsible for the nonselective corticomotor suppression contributing to Partial trial response delays. Sixteen right-handed participants performed a bimanual anticipatory response inhibition task while single- and paired-pulse transcranial magnetic stimulation was delivered to elicit motor evoked potentials in the left first dorsal interosseous muscle. Lift times, amplitude of motor evoked potentials, and long-interval intracortical inhibition were examined across the different trial types (Go, Stop-Left, Stop-Right, Stop-Both). Go trials produced a tight distribution of lift times around the target, whereas those during Partial trials (Stop-Left and Stop-Right) were substantially delayed. The modulation of motor evoked potential amplitude during Stop-Right trials reflected anticipation, suppression, and subsequent reinitiation of movement. Importantly, suppression was present across all Stop trial types, indicative of a “default” nonselective inhibitory process. Compared with blocks containing only Go trials, inhibition increased when Stop trials were introduced but did not differ between trial types. The amount of inhibition was positively correlated with lift times during Stop-Right trials. Tonic levels of inhibition appear to be proactively modulated by task context and influence the speed at which unimanual responses occur after a nonselective “brake” is applied. PMID:27281744

Synthesis, characterization, X-ray crystallography, acetyl cholinesterase inhibition and antioxidant activities of some novel ketone derivatives of gallic hydrazide-derived Schiff bases.

Science.gov (United States)

Gwaram, Nura Suleiman; Ali, Hapipah Mohd; Abdulla, Mahmood Ameen; Buckle, Michael J C; Sukumaran, Sri Devi; Chung, Lip Yong; Othman, Rozana; Alhadi, Abeer A; Yehye, Wageeh A; Hadi, A Hamid A; Hassandarvish, Pouya; Khaledi, Hamid; Abdelwahab, Siddig Ibrahim

2012-02-28

Alzheimer's disease (AD) is the most common form of dementia among older people and the pathogenesis of this disease is associated with oxidative stress. Acetylcholinesterase inhibitors with antioxidant activities are considered potential treatments for AD. Some novel ketone derivatives of gallic hydrazide-derived Schiff bases were synthesized and examined for their antioxidant activities and in vitro and in silico acetyl cholinesterase inhibition. The compounds were characterized using spectroscopy and X-ray crystallography. The ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays revealed that all the compounds have strong antioxidant activities. N-(1-(5-bromo-2-hydroxyphenyl)-ethylidene)-3,4,5-trihydroxybenzohydrazide (2) was the most potent inhibitor of human acetyl cholinesterase, giving an inhibition rate of 77% at 100 μM. Molecular docking simulation of the ligand-enzyme complex suggested that the ligand may be positioned in the enzyme's active-site gorge, interacting with residues in the peripheral anionic subsite (PAS) and acyl binding pocket (ABP). The current work warrants further preclinical studies to assess the potential for these novel compounds for the treatment of AD.

Direct antioxidant properties of methotrexate: Inhibition of malondialdehyde-acetaldehyde-protein adduct formation and superoxide scavenging

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Matthew C. Zimmerman

2017-10-01

Full Text Available Methotrexate (MTX is an immunosuppressant commonly used for the treatment of autoimmune diseases. Recent observations have shown that patients treated with MTX also exhibit a reduced risk for the development of cardiovascular disease (CVD. Although MTX reduces systemic inflammation and tissue damage, the mechanisms by which MTX exerts these beneficial effects are not entirely known. We have previously demonstrated that protein adducts formed by the interaction of malondialdehyde (MDA and acetaldehyde (AA, known as MAA-protein adducts, are present in diseased tissues of individuals with rheumatoid arthritis (RA or CVD. In previously reported studies, MAA-adducts were shown to be highly immunogenic, supporting the concept that MAA-adducts not only serve as markers of oxidative stress but may have a direct role in the pathogenesis of inflammatory diseases. Because MAA-adducts are commonly detected in diseased tissues and are proposed to mitigate disease progression in both RA and CVD, we tested the hypothesis that MTX inhibits the generation of MAA-protein adducts by scavenging reactive oxygen species. Using a cell free system, we found that MTX reduces MAA-adduct formation by approximately 6-fold, and scavenges free radicals produced during MAA-adduct formation. Further investigation revealed that MTX directly scavenges superoxide, but not hydrogen peroxide. Additionally, using the Nrf2/ARE luciferase reporter cell line, which responds to intracellular redox changes, we observed that MTX inhibits the activation of Nrf2 in cells treated with MDA and AA. These studies define previously unrecognized mechanisms by which MTX can reduce inflammation and subsequent tissue damage, namely, scavenging free radicals, reducing oxidative stress, and inhibiting MAA-adduct formation.

TYPE 2 DIABETES IN CHILDREN AND ADOLESCENT: FROM PATHOGENESIS TO TREATMENT

OpenAIRE

A.B. Resnenko

2011-01-01

Dramatic rising prevalence of type 2 diabetes among children and adolescent required from health care providers to develop a new strategies for screening, treatment and prevention of diabetes at this age. Many medications have been developed for treatment of type 2 diabetes in adult. Despite on this, therapeutic modalities in children and adolescent remain extremely limited. This review discussed modern data about pathogenesis diabetes type 2 and main risk-factors. Author presents an update o...

The Jeremiah Metzger Lecture. The pathogenesis of fever in human subjects.

OpenAIRE

Wolff, S. M.; Dinarello, C. A.

1980-01-01

The pathogenesis of fever in man begins with the production of endogenous pyrogen by phagocytic leukocytes in response to exogenous pyrogens (toxic, immunologic or infectious agents). Endogenous pyrogen, a protein, is released from a variety of phagocytic leukocytes and enters the circulation after new messenger RNA and protein are synthesized. Fever is caused by an interaction of endogenous pyrogen with specialized receptors on or near thermosensitive neurons in the thermoregulatory center o...

Ketogenic Diet Improves Brain Ischemic Tolerance and Inhibits NLRP3 Inflammasome Activation by Preventing Drp1-Mediated Mitochondrial Fission and Endoplasmic Reticulum Stress

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Min Guo

2018-03-01

Full Text Available Background: Neuroprotective effects of ketogenic diets (KD have been reported in stroke models, and nucleotide-binding domain (NOD-like receptor protein 3 (NLRP3 inflammasome has also been implicated in the pathogenesis of stroke. This study aimed to investigate the effects of KD on NLRP3 inflammasome and explore the potential molecular mechanisms.Methods: In in vivo study, mice were fed with KD for 3 weeks and then subjected to middle cerebral artery occlusion/reperfusion (MCAO/R-injury. In in vitro study, SH-SY-5Y cells were treated with β-hydroxybutyrate (BHB followed by oxygen–glucose deprivation/reoxygenation (OGD/R. NLRP3 inflammasome activation and related regulatory mechanisms were evaluated.Results: Mice fed with KD had increased tolerance to MCAO/R. KD inhibited endoplasmic reticulum (ER stress and suppressed TXNIP/NLRP3 inflammasome activation in the brain. The in vitro study showed BHB (10 mM prevented the mitochondrial translocation of dynamin-related protein 1 (Drp1 to inhibit mitochondrial fission. Furthermore, BHB decreased reactive oxygen species (ROS generation, inhibited ROS-NLRP3 pathway in OGD/R-treated cells, and suppressed ER stress-induced NLRP3 inflammasome activation.Conclusions: KD may suppress ER stress and protect mitochondrial integrity by suppressing the mitochondrial translocation of Drp1 to inhibit NLRP3 inflammasome activation, thus exerting neuroprotective effects. Our findings provide evidence for the potential application of KD in the prevention of ischemic stroke.

Advancements in the Underlying Pathogenesis of Schizophrenia: Implications of DNA Methylation in Glial Cells.

Science.gov (United States)

Chen, Xing-Shu; Huang, Nanxin; Michael, Namaka; Xiao, Lan

2015-01-01

Schizophrenia (SZ) is a chronic and severe mental illness for which currently there is no cure. At present, the exact molecular mechanism involved in the underlying pathogenesis of SZ is unknown. The disease is thought to be caused by a combination of genetic, biological, psychological, and environmental factors. Recent studies have shown that epigenetic regulation is involved in SZ pathology. Specifically, DNA methylation, one of the earliest found epigenetic modifications, has been extensively linked to modulation of neuronal function, leading to psychiatric disorders such as SZ. However, increasing evidence indicates that glial cells, especially dysfunctional oligodendrocytes undergo DNA methylation changes that contribute to the pathogenesis of SZ. This review primarily focuses on DNA methylation involved in glial dysfunctions in SZ. Clarifying this mechanism may lead to the development of new therapeutic interventional strategies for the treatment of SZ and other illnesses by correcting abnormal methylation in glial cells.

Advancements in the Underlying Pathogenesis of Schizophrenia: Implications of DNA Methylation in Glial Cells

Directory of Open Access Journals (Sweden)

Xin-Shu eChen

2015-12-01

Full Text Available Schizophrenia (SZ）is a chronic and severe mental illness for which currently there is no cure. At present, the exact molecular mechanism involved in the underlying pathogenesis of SZ is unknown. The disease is thought to be caused by a combination of genetic, biological, psychological, and environmental factors. Recent studies have shown that epigenetic regulation is involved in SZ pathology. Specifically, DNA methylation, one of the earliest found epigenetic modifications, has been extensively linked to modulation of neuronal function, leading to psychiatric disorders such as SZ. However, increasing evidence indicates that glial cells, especially dysfunctional oligodendrocytes undergo DNA methylation changes that contribute to the pathogenesis of SZ. This review primarily focuses on DNA methylation involved in glial dysfunctions in SZ. Clarifying this mechanism may lead to the development of new therapeutic interventional strategies for the treatment of SZ and other illnesses by correcting abnormal methylation in glial cells.

Immunogenetics and genetic susceptibility in the pathogenesis of autoimmune hepatitis

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Das Anup K

2014-11-01

Full Text Available vAutoimmune hepatitis is a progressive liver disease. Its pathogenesis is unclear, but needs a ‘trigger’ to initiate the disease in a genetically susceptible person. The susceptibility is partly related to MHCII class genes, and more so with human leukocyte antigen (HLA. Several mechanisms have been proposed which, however, cannot fully explain the immunologic findings in autoimmune hepatitis. The susceptibility to any autoimmune disease is determined by several factors where genetic and immunological alterations, along with, environmental factor are active. MHCII antigens as a marker for AIH, or a predictor of treatment response and prognosis has been investigated. Since MHCII antigens show significant ethnic heterogeneity, mutations in MHCII may merely act as only precursors of the surface markers of immune cells, which can be of significance, because the changes in HLA and MHC are missing in certain populations. One such marker is the CTLA-4 (CD152 gene mutation, reported in the phenotypes representing susceptibility to AIH. Other candidate genes of cytokines, TNF, TGF-beta1 etc, have also been investigated but with unvalidated results. Paediatric AIH show differences in genetic susceptibility. Genetic susceptibility or resistance to AIH may be associated with polypeptides in DRB1 with certain amino-acid sequences. Understanding which genes are implicated in genesis and/or disease progression will obviously help to identify key pathways in AIH and provide better insights into its pathogenesis. But studies to identify responsible genes are complex because of the complex trait of AIH.

Pathogenesis and biomarkers of carcinogenesis in ulcerative colitis

DEFF Research Database (Denmark)

Thorsteinsdottir, Sigrun; Gudjonsson, Thorkell; Nielsen, Ole Haagen

2011-01-01

on the current understanding of the pathogenesis of ulcerative colitis-associated colorectal cancer and how this knowledge can be transferred into patient management to assist clinicians and pathologists in identifying patients with ulcerative colitis who have an increased risk of colorectal cancer. Inflammation......One of the most serious complications of ulcerative colitis is the development of colorectal cancer. Screening patients with ulcerative colitis by standard histological examination of random intestinal biopsy samples might be inefficient as a method of cancer surveillance. This Review focuses......-driven mechanisms of DNA damage, including the generation and effects of reactive oxygen species, microsatellite instability, telomere shortening and chromosomal instability, are reviewed, as are the molecular responses to genomic stress. We also discuss how these mechanisms can be translated into usable biomarkers...

HIV-1 Nef in Macrophage-Mediated Disease Pathogenesis

Science.gov (United States)

Lamers, Susanna L.; Fogel, Gary B.; Singer, Elyse J.; Salemi, Marco; Nolan, David J.; Huysentruyt, Leanne C.; McGrath, Michael S.

2013-01-01

Combined anti-retroviral therapy (cART) has significantly reduced the number of AIDS-associated illnesses and changed the course of HIV-1 disease in developed countries. Despite the ability of cART to maintain high CD4+ T-cell counts, a number of macrophage-mediated diseases can still occur in HIV-infected subjects. These diseases include lymphoma, metabolic diseases, and HIV-associated neurological disorders. Within macrophages, the HIV-1 regulatory protein “Nef” can modulate surface receptors, interact with signaling pathways, and promote specific environments that contribute to each of these pathologies. Moreover, genetic variation in Nef may also guide the macrophage response. Herein, we review findings relating to the Nef–macrophage interaction and how this relationship contributes to disease pathogenesis. PMID:23215766

Inhibition of multiple pathogenic pathways by histone deacetylase inhibitor SAHA in a corneal alkali-burn injury model

Science.gov (United States)

Li, Xinyu; Zhou, Qinbo; Hanus, Jakub; Anderson, Chastain; Zhang, Hongmei; Dellinger, Michael; Brekken, Rolf; Wang, Shusheng

2013-01-01

Neovascularization (NV) in the cornea is a major cause of vision impairment and corneal blindness. Hemangiogenesis and lymphangiogenesis induced by inflammation underlie the pathogenesis of corneal NV. The current mainstay treatment, corticosteroid, treats the inflammation associated with corneal NV, but is not satisfactory due to such side effects as cataract and the increase in intraocular pressure. It is imperative to develop a novel therapy that specifically targets the hemangiogenesis, lymphangiogenesis and inflammation pathways underlying corneal NV. Histone deacetylase inhibitors (HDACi) have been in clinical trials for cancer and other diseases. In particular, HDACi suberoylanilide hydroxamic acid (SAHA, vorinostat, Zolinza) has been approved by the FDA for the treatment of cutaneous T-cell lymphoma. The functional mechanism of SAHA in cancer and especially in corneal NV remains unclear. Here, we show that topical application of SAHA inhibits neovascularization in an alkali-burn corneal injury model. Mechanistically, SAHA inhibits corneal NV by repressing hemangiogenesis, inflammation pathways and previously overlooked lymphangiogenesis. Topical SAHA is well tolerated on the ocular surface. In addition, the potency of SAHA in corneal NV appears to be comparable to the current steroid therapy. SAHA may possess promising therapeutic potential in alkali-burn corneal injury and other inflammatory neovascularization disorders. PMID:23186311

β-Cell Autophagy in Diabetes Pathogenesis.

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Marasco, Michelle R; Linnemann, Amelia K

2018-05-01

Nearly 100 years have passed since Frederick Banting and Charles Best first discovered and purified insulin. Their discovery and subsequent improvements revolutionized the treatment of diabetes, and the field continues to move at an ever-faster pace with respect to unique treatments for both type 1 and type 2 diabetes. Despite these advances, we still do not fully understand how apoptosis of the insulin-producing β-cells is triggered, presenting a challenge in the development of preventative measures. In recent years, the process of autophagy has generated substantial interest in this realm due to discoveries highlighting its clear role in the maintenance of cellular homeostasis. As a result, the number of studies focused on islet and β-cell autophagy has increased substantially in recent years. In this review, we will discuss what is currently known regarding the role of β-cell autophagy in type 1 and type 2 diabetes pathogenesis, with an emphasis on new and exciting developments over the past 5 years. Further, we will discuss how these discoveries might be translated into unique treatments in the coming years.

Fibromyalgia Pathogenesis and Treatment Options Update.

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Chinn, Steven; Caldwell, William; Gritsenko, Karina

2016-04-01

This review article presents and summarizes up-to-date literature on the clinical manifestations, diagnosis, pathophysiological mechanisms, and treatment options for fibromyalgia patients. First, the most recent diagnostic criteria for fibromyalgia, as put forth by the American College of Rheumatology will be summarized. Clinical features, including chronic widespread pain, hyperalgesia, mood disorders, anxiety, and disturbed sleep patterns will be explored in-depth. The pathogenesis and pathophysiology of fibromyalgia involves alterations in multiple ascending and descending central nervous system pathways, as well as peripheral pathways, leading to heightened pain sensitivity. Risk factors have been studied extensively, and the most recent research focuses on various genetic influences and the contributions of stress and poor sleep. Lastly, the discussion in this article focuses on treatment options for fibromyalgia; some have been mainstay options for many years. Pharmacological agents include tricyclic antidepressants, anti-epileptic drugs, selective serotonin reuptake inhibitors, norepinephrine/serotonin reuptake inhibitors, as well as some investigational agents. The evidence behind non-pharmacologic treatments, including massage therapy, exercise, and acupuncture, are discussed.

Qi-Dong-Huo-Xue-Yin Inhibits Inflammation in Acute Lung Injury in Mice via Toll-Like Receptor 4/Caveolin-1 Signaling

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Li-Ying Xu

2018-01-01

Full Text Available Acute lung injury (ALI is a critical illness with no current effective treatment. Caveolin-1 indirectly activates inflammation-associated signaling pathways by inhibiting endothelial nitric oxide synthase (eNOS. This induces an imbalance between pro- and anti-inflammatory cytokine levels, which are involved in the pathogenesis of ALI. The compound Chinese prescription Qi-Dong-Huo-Xue-Yin (QDHXY is efficacious for ALI treatment via an anti-inflammatory effect; however, the exact underlying mechanism is unknown. Therefore, we explored the protective effect of QDHXY against lipopolysaccharide- (LPS- induced ALI in mice. Histopathological changes in mouse lung tissues were studied. Furthermore, alterations in the serum levels of pro- and anti-inflammatory cytokines were investigated. The levels of tumor necrosis factor- (TNF-α, interleukin- (IL- 6, IL-1β, and interferon-γ-induced protein 10 in bronchoalveolar lavage fluid were measured. Additionally, the expression levels of myeloid differentiation factor 88 (MyD88, caveolin-1, and eNOS were assessed. QDHXY significantly reduced lung infiltration with inflammatory cells and the production of serum pro- and anti-inflammatory cytokines and inhibited the expression of TNF-α, IL-1β, caveolin-1, and MyD88 but not eNOS. These indicate that QDHXY significantly improved the balance between pro- and anti-inflammatory cytokine levels, possibly by inhibiting the caveolin-1 signaling pathway. Therefore, QDHXY may be a potential treatment for ALI.

Recent Insights into the Pathogenesis of Type AA Amyloidosis

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J. C. H. van der Hilst

2011-01-01

Full Text Available The amyloidoses are a group of life-threatening diseases in which fibrils made of misfolded proteins are deposited in organs and tissues. The fibrils are stable, insoluble aggregates of precursor proteins that have adopted an antiparallel β-sheet structure. In type AA, or reactive, amyloidosis, the precursor protein of the fibrils is serum amyloid A (SAA. SAA is a 104-amino-acid protein that is produced in the liver in response to proinflammatory cytokines. Although the protein that is produced by the liver contains 104 amino acids, only the N-terminal 66–76 amino acids are found in amyloid fibrils. Furthermore, SAA has been shown to have an α-helical structure primarily. Thus, for SAA to be incorporated into an amyloid fibril, two processes have to occur: C-terminal cleavage and conversion into a β-sheet. Only a minority of patients with elevated SAA levels develop amyloidosis. Factors that contribute to the risk of amyloidosis include the duration and degree of SAA elevation, polymorphisms in SAA, and the type of autoinflammatory syndrome. In the Hyper-IgD syndrome, amyloidosis is less prevalent than in the other autoinflammatory diseases. In vitro work has shown that the isoprenoid pathway influences amyloidogenesis by farnesylated proteins. Although many proteins contain domains that have a potential for self-aggregation, amyloidosis is only a very rare event. Heat shock proteins (HSPs are chaperones that assist other proteins to attain, maintain, and regain a functional conformation. In this review, recent insights into the pathogenesis of amyloidosis are discussed, in addition to a new hypothesis for a role of HSPs in the pathogenesis of type AA.

The pathogenesis of amyloidosis in periodic disease: Some aspects

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Z. T. Djndoyan

2014-07-01

Full Text Available Sufficient information indicating the implication of dysfunction of interleukins (IL-6 and IL-1 in particular in the pathogenesis of amyloidosis in a number of autoinflammatory, rheumatic, and autoimmune diseases, including those in periodic disease (PD, has been recently accumulated. Its genetic defect – pirin mutation – gives rise to an alternative innate immune response (phagocytic cell activation to secrete IL-1 by macrophages and to activate T-helper cells. This causes imbalance in the synthesis of proinflammatory (IL-6, IL-8, and TNF-α and anti-inflammatory (IL-4, IL-10, and IL-1 receptor antagonist cytokines. Moreover, the uncontrolled macrophage (monocyte secretion of a great deal of IL-6 that together with IL-1 is a mediator of the synthesis of the serum amyloid fibril protein precursor SAA by hepatocytes, neutrophils, and fibroblasts plays one of the key roles in the pathogenesis of PD through amyloidosis. With this, IL-6 stimulates the inflammatory process, by enhancing the release of lysosomal enzymes, reactive oxygen species, and eicosanoids (prostaglandins, leukotrienes, thromboxane from the polymorphic nuclear leukocytes, macrophages, endotheliocytes, and fibroblasts and by augmenting the chemotaxis of macrophages and neutrophils, and the degranulation of the latter, i.e. through its action on the effector cells of inflammation, and prepares the tissue basis for amyloid deposits in this fashion. Thus, the analysis of literary and own materials gives grounds to suggest that pirin mutation is a trigger of the synthesis of IL-1 and IL-6 in PD and their hypersecretion is an initial link of the synthesis of SAA.