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Kaempferol, a flavonoid, promotes osteoblast mineralization in vitro and bone formation in vivo; however, its mechanism of action is yet unknown. We adopted proteomic approach to identify the differential effect of kaempferol on rat primary calvarial osteoblasts during mineralization. The primary rat calvarial osteoblasts were treated with kaempferol (5.0 microM) for 9 days under mineralizing condition that resulted in significant increase in alkaline phosphatase activity and mineralization of the cells. Further, 2-D analysis of the kaempferol-treated osteoblast lysates revealed 18 differentially expressed proteins (nine upregulated and nine downregulated) on the basis of >/<2.0-fold as cut-off (p<0.01) that were then identified by MALDI-TOF MS. These included cytoskeletal proteins, intracellular signaling protein, chaperone, extracellular matrix protein, and proteins involved in glycolysis and cell-matrix interactions. Proteomics data were confirmed by Western blotting and quantitative real-time PCR by randomly selecting two upregulated and two downregulated proteins. Western blot analysis confirmed upregulation of HSP-70 and cytokeratin-14 levels, and downregulation of aldose reductase and caldesmon expression. We further demonstrated that kaempferol treatment inhibits aldose reductase activity in osteoblasts indicating an altered cellular metabolism by decelerating polyol pathway that was associated with the kaempferol-induced osteoblast mineralization. In conclusion, this is a first comprehensive study on the differential regulation of proteins by kaempferol in primary osteoblast, which would further help to elucidate the role of the identified proteins in the process of osteoblast mineralization. Source

We investigated the hypolipidemic effect of glycyrrhizic acid (GA) focused on the mRNA expression and hepatic HMG-CoA reductase (HMGR) activity in hamsters fed a high-fat diet. Male Syrian Golden hamsters were fed a high fat diet for 8 weeks for induction of dyslipidemia and were treated with GA and fenofibrate. The concentrations of plasma total cholesterol and triglyceride were significantly lower in the GA-treated group than in the control group. The GA treatment significantly decreased Apo B, Lp(a), and cholesterol-ester-transport protein (CETP) concentrations, but increased Apo A-I levels and the Apo A-I/ Apo B ratio. The contents of cholesterol and triglyceride in hepatic tissue were significantly lower in the GA group than in the control group. Real-time PCR analysis revealed that HMGR mRNA expression was significantly lower in the GA group than in the control group. These results indicate that GA treatment reduces plasma cholesterol by down-regulating hepatic HMGR mRNA expression in hamsters fed a high fructose-fat diet. Source

Mishra P.R.,Central Drug Research Institute
Journal of Biomedical Nanotechnology | Year: 2011

A ciprofloxacin (CFn)-loaded lipid emulsion was developed for treatment of intra-abdominal infections, especially sepsis. Loading efficiency depended on the proportion of chitosan (CH) and sodium deoxycholate (SDC). The average globule size was 225 to 325 nm. Animal survival improved when the prototype formulation was administered to LPS-induced septic mice. At 4 μg/ml, reduction in TNF-α and NO production were observed (P < 0.05) but at lower concentration these changes were not significant (P > 0.05) as compared to positive control (LPS-1 μg/ml). This indicates that chitosan can modify LPS interaction with macrophages, and that formulations have potential to control inflammation associated with sepsis. Copyright © 2011 American Scientific Publishers All rights reserved. Source

Shaha C.,National Institute of Immunology | Tripathi R.,National Institute of Immunology | Prasad Mishra D.,Central Drug Research Institute
Philosophical Transactions of the Royal Society B: Biological Sciences | Year: 2010

Cellular apoptosis appears to be a constant feature in the adult testis and during early development. This is essential because mammalian spermatogenesis is a complex process that requires precise homeostasis of different cell types. This review discusses the latest information available on male germ cell apoptosis induced by hormones, toxins and temperature in the context of the type of apoptotic pathway either the intrinsic or the extrinsic that may be used under a variety of stimuli. The review also discusses the importance of mechanisms pertaining to cellular apoptosis during testicular development, which is independent of exogenous stimuli. Since instances of germ cell carcinoma have increased over the past few decades, the current status of research on apoptotic pathways in teratocarcinoma cells is included. One other important aspect that is covered in this review is microRNA-mediated control of germ cell apoptosis, a field of research that is going to see intense activity in near future. Since knockout models of various kinds have been used to study many aspects of germ cell development, a comprehensive summary of literature on knockout mice used in reproduction studies is also provided. © 2010 The Royal Society. Source

Singh A.P.,Central Drug Research Institute | Rajender S.,Central Drug Research Institute
Reproductive BioMedicine Online | Year: 2015

A number of physiological events, such as sperm hyperactivation, chemotaxis towards the egg, capacitation and acrosome reaction, are triggered by activation of sperm ion channels in response to a diverse range of chemical cues. Cation channel of sperm (CatSper), a sperm-specific ion channel, is unique in orchestrating the events for fertilization, and seems to be exclusively evolved for sperm function and male fertility. CatSper acts as a polymodal, chemosensory calcium channel and plays a vital role in the regulation of sperm hyperactivation. CatSper knockout models and application of patch clamp recordings have shown that it is indispensable for male fertility, and mutations and deletions in CatSper gene(s) may lead to infertility. In fact, mutations in CatSper1 and 2 have been identified in infertile individuals; however, CatSper3 and 4 have not been explored. Restricted localization and expression of CatSper in sperm offer an added advantage to developing gamete-based safe non-hormonal contraceptives. This review concisely covers identification, structure, function, and mechanism of action of CatSper channels. The functional importance of this complex ion channel in sperm motility and male fertility is highlighted for further research on male fertility, infertility, and contraception. © 2014 Reproductive Healthcare Ltd. Published by Elsevier Inc. All rights reserved. Source

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