Prokaryotic and eukaryotic integral membrane proteins have similar architecture

Integral membrane proteins constitute a major constituent of lipid bilayer both in prokaryotes and eukaryotes. The statistical analysis was carried out to determine the bias in amino acid distribution between prokaryotic and eukaryotic integral membrane proteins (pIntMPs and eIntMPs). Our results indicate that both pIntMPs and eIntMPs demonstrate the striking similarity in amino acid distribution in their transmembrane and extramembranous region. pIntMPs have relatively greater functional importance for Gly and Asn in comparison to eIntMPs.     

Methionine aminopeptidase-2 blockade reduces chronic collagen-induced arthritis: potential role for angiogenesis inhibition

The enzyme methionine aminopeptidase-2 (MetAP-2) is thought to play an important function in human endothelial cell proliferation, and as such provides a valuable target in both inflammation and cancer. Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with increased synovial vascularity, and hence is a potential therapeutic target for angiogenesis inhibitors. We examined the use of PPI-2458, a selective non-reversible inhibitor of MetAP-2, in disease models of RA, namely acute and chronic collagen-induced arthritis (CIA) in mice. Whilst acute CIA is a monophasic disease, CIA induced with murine collagen type II manifests as a chronic relapsing arthritis and mimics more closely the disease course of RA. Our study showed PPI-2458 was able to reduce clinical signs of arthritis in both acute and chronic CIA models. This reduction in arthritis was paralleled by decreased joint inflammation and destruction. Detailed mechanism of action studies demonstrated that PPI-2458 inhibited human endothelial cell proliferation and angiogenesis in vitro, without affecting production of inflammatory cytokines. Furthermore, we also investigated release of inflammatory cytokines and chemokines from human RA synovial cell cultures, and observed no effect of PPI-2458 on spontaneous expression of cytokines and chemokines, or indeed on the angiogenic molecule vascular endothelial growth factor (VEGF). These results highlight MetAP-2 as a good candidate for therapeutic intervention in RA.     

Computational insights into diverse aspects of glutathione S-transferase gene family in Papaver somniferum

Journal of Plant Research - Plant glutathione S-transferases are an ancient protein superfamily having antioxidant activity. These proteins are primarily involved in diverse plant functions such as...     

TNF-alpha induced NFκB signaling and p65 (RelA) overexpression repress Cldn5 promoter in mouse brain endothelial cells

Inflammatory cytokine TNFα enhances permeability of brain capillaries constituting blood brain barrier (BBB). In the monoculture endothelial models of BBB TNFα alters tight junction (TJ) structure and protein content. Claudin-5 (Cldn5) is a key TJ protein whose expression in the brain endothelial cells is critical to the function of BBB. TNFα reduces Cldn5 promoter activity and mRNA expression in mouse brain derived endothelial cells but the regulatory elements and signaling mechanism involved are not defined. Here we report that TNFα acts through NFκB signaling and requires a conserved promoter region for the down-regulation of Cldn5 expression. Overexpression of the NFκB subunit p65 (RelA) alone repressed Cldn5 promoter activity in mouse brain endothelial cells. We observed partial loss of Cldn5 protein expression after prolonged TNFα treatment in primary endothelial culture isolated from C56BL/6 mice brain. Taken together, our results confirm and extend previous observations of TNFα induced down-regulation of Cldn5 expression in mouse brain endothelial cells.     

Impact of season on antioxidants,nutritional metabolic status,cortisol and heat shock proteins in Hariana and Sahiwal cattle

The aim of this study was to evaluate the effects of summer and winter seasons on antioxidant status, body reserve mobilization and biomarkers of stress in Hariana and Sahiwal cows. Twelve lactating cows (six of each Hariana and Sahiwal cows) were included in summer (May to July) and winter season (November to January) study. Microclimatic observations were recorded on daily basis during the experimental period. In both seasons, blood samples were collected at fortnightly intervals for analysis of total antioxidant activity, non-esterified fatty acids (NEFA), β-Hydroxybutyric acid (BHBA), heat shock protein 70 and 90 (HSP70 and HSP90). Antioxidant activity reduced significantly (p < 0.05) in Hariana cattle during summers as compared to winters; whereas, seasonal variation exerts no effect on antioxidant activity in Sahiwal. Blood NEFA concentration was similar among both the breeds over both the seasons but reduced significantly (p < 0.05) during summer season as compared to winters in both the breeds. BHBA concentration was significantly higher (p < 0.05) in Hariana cows than Sahiwal cows during winters, however, no effect on BHBA level was observed during summer season in both the breeds. Significantly, lower plasma cortisol level (p < 0.05) was found during winter season in Sahiwal as well as Hariana cows. Further, Sahiwal exhibited lower plasma cortisol as compared to Hariana in both the seasons. HSP 70 and 90 showed non-significant differences between breeds within both the seasons. However, significantly, lower plasma HSP 70 levels (p < 0.05) were reported during winter season in Sahiwal as well as in Hariana cows. Results of present study revealed that indigenous Sahiwal is more heat tolerant as compared to Hariana breed.     

Association of homocysteine and methylene tetrahydrofolate reductase (MTHFR C677T) gene polymorphism with coronary artery disease (CAD) in the population of North India

The implications of the methylene tetrahydrofolate reductase (MTHFR) gene and the level of homocysteine in the pathogenesis of coronary artery disease (CAD) have been extensively studied in various ethnic groups. Our aim was to discover the association of MTHFR (C677T) polymorphism and homocysteine level with CAD in north Indian subjects. The study group consisted of 329 angiographically proven CAD patients, and 331 age and sex matched healthy individuals as controls. MTHFR (C677T) gene polymorphism was detected based on the polymerase chain reaction and restriction digestion with HinfI. Total homocysteine plasma concentration was measured using immunoassay. T allele frequency was found to be significantly higher in patients than in the control group. We found significantly elevated levels of mean homocysteine in the patient group when compared to the control group (p = 0.00). Traditional risk factors such as diabetes, hypertension, smoking habits, a positive family history and lipid profiles (triglyceride, total cholesterol, HDL-cholesterol, LDL-cholesterol, VLDL-cholesterol), were found significantly associated through univariate analysis. Furthermore, multivariable logistics regression analysis revealed that CAD is significantly and variably associated with diabetes, hypertension, smoking, triglycerides and HDL-cholesterol. Our findings showed that MTHFR C677T polymorphism and homocysteine levels were associated with coronary artery disease in the selected population.     

Cadmium and lead interactive effects on oxidative stress and antioxidative responses in rice seedlings

Interactive effects of two heavy metal pollutants Cd and Pb in the growth medium were examined on their uptake, production of reactive oxygen species (ROS), induction of oxidative stress and antioxidative defence responses in Indica rice (Oryza sativa L.) seedlings. When rice seedlings in sand culture were exposed to 150 μM Cd (NO₃)₂ or 600 μM Pb (CH₃COO)₂ individually or in combination for 8–16 days, a significant reduction in root/shoot length, fresh weight, relative water content, photosynthetic pigments and increased production of ROS (O₂˙^? and H₂O₂) was observed. Both Cd and Pb were readily taken up by rice roots and localisation of absorbed metals was greater in roots than in shoots. When present together in the growth medium, uptake of both the metals Cd and Pb declined by 25–40 %. Scanning electron microscope (SEM) imaging of leaf stomata revealed that Pb caused more distortion in the shape of guard cells than Cd. Dithizone staining of roots showed localisation of absorbed Cd on root hairs and epidermal cells. Both Cd and Pb caused increased lipid peroxidation, protein carbonylation, decline in protein thiol and increase in non-protein thiol. The level of reduced forms of non-enzymic antioxidants glutathione (GSH) and ascorbate (AsA) and their redox ratios (GSH/AsA) declined, whereas the activities of antioxidative enzymes superoxide dismutase (SOD) and guaiacol peroxidase (GPX) increased in metal treated seedlings compared to controls. In-gel activity staining also revealed increased intensities of SOD and GPX isoforms with metal treatments. Catalase (CAT) activity increased during early days (8 days) of metal exposure and declined by 16 days. Results suggest that oxidative stress is an important component in expression of Cd and Pb toxicities in rice, though uptake of both metals gets reduced considerably when present together in the medium.