MTA1 coregulation of transglutaminase 2 expression and function during inflammatory response

Although both metastatic tumor antigen 1 (MTA1), a master chromatin modifier, and transglutaminase 2 (TG2), a multifunctional enzyme, are known to be activated during inflammation, it remains unknown whether these molecules regulate inflammatory response in a coordinated manner. Here we investigated the role of MTA1 in the regulation of TG2 expression in bacterial lipopolysaccharide (LPS)-stimulated mammalian cells. While studying the impact of MTA1 status on global gene expression, we unexpectedly discovered that MTA1 depletion impairs the basal as well as the LPS-induced expression of TG2 in multiple experimental systems. We found that TG2 is a chromatin target of MTA1 and of NF-κB signaling in LPS-stimulated cells. In addition, LPS-mediated stimulation of TG2 expression is accompanied by the enhanced recruitment of MTA1, p65RelA, and RNA polymerase II to the NF-κB consensus sites in the TG2 promoter. Interestingly, both the recruitment of p65 and TG2 expression are effectively blocked by a pharmacological inhibitor of the NF-κB pathway. These findings reveal an obligatory coregulatory role of MTA1 in the regulation of TG2 expression and of the MTA1-TG2 pathway, at least in part, in LPS modulation of the NF-κB signaling in stimulated macrophages.     

Solid state degradation of paddy straw by Phlebia floridensis in the presence of different supplements for improving its nutritive status

Effect of different supplements on the degradation of paddy (rice) straw by Phlebia floridensis was studied and the conditions for best ligninolysis, lower loss in total organic matter (TOM) and enhancement in in vitro digestibility (IVD) were established. Effect of different supplements on lignocellulolytic enzymes production, degradation of cell wall fibres of paddy straw and their resultant effect on its nutritional quality was studied. Ammonium chloride, soya bean meal and moisture content were selected for response surface study on the basis of their important role in degradation. Finally, the process was successfully scaled up from 5 g to 200 g under optimized sold state conditions and the straw quality was upgraded in terms of increased IVD (40%) with a moderate loss (6%) in TOM during 20 days of incubation. Protein content, amino acid, total phenolics and antioxidant properties of the paddy straw improved with its fermentation.     

Novel 3-chlorooxazolidin-2-ones as antimicrobial agents

Antimicrobial resistance against many known therapeutics is on the rise. We examined derivatives of 3-chlorooxazolidin-2-one 1a (X = H) as antibacterial and antifungal agents. The key findings were that the activity and apparent in vitro cytotoxicity could be controlled by the substitution of charged solubilizers at the 4- and 5- positions. These changes both significantly increase the antifungal potency and decrease cytotoxicity. Particularly effective were trialkylammonium groups which led to 400- to 600-fold increases in the antifungal therapeutic index when compared to their unsubstituted counterparts.     

Synthesis and antihyperglycemic activity of phenolic C-glycosides

Various phenolic C-glycosides were evaluated for their in vitro and in vivo antihyperglycemic activity employing glucose uptake by rat muscle cell lines (L-6) and low dosed-streptozotocin-induced diabetic rats, respectively. Some of phenolic C-glycosides were isolated from Pterocarpus marsupium and Ulmus wallichiana and other were synthesized by unprotected sugar and phloroacetophenone using Sc(OTf)₃ in aqueous ethanol. Eight among tested compounds showed significant lowering of blood glucose level on low dosed-streptozotocin-induced diabetic rats. The compound 24 lowered the blood glucose levels by 34.9% and 33.6% during 0-5 h and 0-24 h, respectively, at the dose of 25 mg/kg body weight which is comparable to standard antidiabetic drug metformin.     

Discovery of 2,4-bis-arylamino-1,3-pyrimidines as insulin-like growth factor-1 receptor (IGF-1R) inhibitors

The insulin-like growth factor-1 receptor (IGF-1R) plays an important role in the regulation of cell growth and differentiation, and in protection from apoptosis. IGF-1R has been shown to be an appealing target for the treatment of human cancer. Herein, we report the synthesis, structure-activity relationships (SAR), X-ray cocrystal structure and in vivo tumor study results for a series of 2,4-bis-arylamino-1,3-pyrimidines.     

Synthesis and anti-inflammatory activity of novel biscoumarin-chalcone hybrids

A series of synthesized novel biscoumarin-chalcone hybrids were evaluated for their anti-inflammatory and antioxidant activity. The tested compounds significantly inhibit the carrageenin induced paw oedema in albino rats and also exhibit important scavenging activities. These compounds thus constitute an interesting template for the design of new therapeutic tools against inflammation.     

Combinatorial reshaping of a lipase structure for thermostability: Additive role of surface stabilizing single point mutations

Thermostable lipases are of high priority for industrial applications. In the present study, targeted improvement of the thermostability of a lipase from metagenomic origin was examined by using a combinatorial protein engineering approach exploring additive effects of single amino acid substitutions. A variant (LipR5) was generated after combination of two thermostabilizing mutations (R214C & N355K). Thermostability of the variant enzyme was analyzed by half-life measurement and circular dichroism (CD). To assess whether catalytic properties were affected by mutation, the optimal reaction conditions were determined. The protein LipR5, displayed optimum activity at 50 °C and pH 8.0. It showed two fold enhancement in thermostability (at 60 °C) as compared to LipR3 (R214C) and nearly 168 fold enhancement as compared to parent enzyme (LipR1). Circular dichroism and fluorescence study suggest that the protein structure had become more rigid and stable to denaturation. Study of 3D model suggested that Lys355 was involved in formation of a Hydrogen bond with OE1 of Glu284. Lys355 was also making salt bridge with OE2 of Glu284.     

Mammalian Target of Rapamycin (mTOR) Inhibition with Rapamycin Improves Cardiac Function in Type 2 Diabetic Mice: POTENTIAL ROLE OF ATTENUATED OXIDATIVE STRESS AND ALTERED CONTRACTILE PROTEIN EXPRESSION*

Elevated mammalian target of rapamycin (mTOR) signaling contributes to the pathogenesis of diabetes, with increased morbidity and mortality, mainly because of cardiovascular complications. Because mTOR inhibition with rapamycin protects against ischemia/reperfusion injury, we hypothesized that rapamycin would prevent cardiac dysfunction associated with type 2 diabetes (T2D). We also investigated the possible mechanisms and novel protein targets involved in rapamycin-induced preservation of cardiac function in T2D mice. Adult male leptin receptor null, homozygous db/db, or wild type mice were treated daily for 28 days with vehicle (5% DMSO) or rapamycin (0.25 mg/kg, intraperitoneally). Cardiac function was monitored by echocardiography, and protein targets were identified by proteomics analysis. Rapamycin treatment significantly reduced body weight, heart weight, plasma glucose, triglyceride, and insulin levels in db/db mice. Fractional shortening was improved by rapamycin treatment in db/db mice. Oxidative stress as measured by glutathione levels and lipid peroxidation was significantly reduced in rapamycin-treated db/db hearts. Rapamycin blocked the enhanced phosphorylation of mTOR and S6, but not AKT in db/db hearts. Proteomic (by two-dimensional gel and mass spectrometry) and Western blot analyses identified significant changes in several cytoskeletal/contractile proteins (myosin light chain MLY2, myosin heavy chain 6, myosin-binding protein C), glucose metabolism proteins (pyruvate dehydrogenase E1, PYGB, Pgm2), and antioxidant proteins (peroxiredoxin 5, ferritin heavy chain 1) following rapamycin treatment in db/db heart. These results show that chronic rapamycin treatment prevents cardiac dysfunction in T2D mice, possibly through attenuation of oxidative stress and alteration of antioxidants and contractile as well as glucose metabolic protein expression.