Srivastava R.A.K.,Piramal Life science Ltd.
Atherosclerosis | Year: 2011
Background: Fenofibrate, a PPAR-α agonist and rosiglitazone, a PPAR-γ agonist, reduce triglycerides and fatty acids in humans and in animal disease models. The efficacy of PPAR-α agonists in mouse model of human atherosclerosis disease has shown mixed results, and efficacy of PPAR-γ and liver X receptor (LXR) agonists has not been evaluated in cholesterol ester transfer protein (CETP) producing animal models. Methods and results: The efficacy of PPAR-α, PPAR-γ and LXR agonists on lipid lowering and antiatherosclerotic activities was studied in atherosclerosis-susceptible F 1B hamster that showed greater responsiveness to dietary fat and cholesterol (HFHC) diet and increased severity of atherosclerosis compared to Golden Syrian (GS) hamsters (aortic lesion 0.3% in GS vs 5% in F 1B). F 1B hamsters were fed HFHC diet and simultaneously treated with fenofibrate, rosiglitazone, and T0901317 (a pan LXR agonist) for 8 weeks. Fenofibrate lowered triglycerides and LDL-C by >80%, rosiglitazone did not significantly impact plasma lipid levels, and as expected, T0901317 increased triglycerides by 3-fold and HDL-C by 50%. The lesions in the aortic arch area as measured by en face method, decreased by 81%, 38% and 35%, following fenofibrate, rosiglitazone, and T0901317 treatments, respectively. In F 1B hamster regression model, fenofibrate decreased levels of triglycerides and LDL-C by >85%, and LDL-C by >70%, respectively, which resulted in ∼50% regression of aortic lesions compared to vehicle treated group, and ∼36% compared to baseline. Conclusions: These results demonstrate that: (a) F 1B hamster is more sensitive to developing diet-induced hyperlipidemia and atherosclerosis; and (b) the greater antiatherosclerotic efficacy of fenofibrate occurred primarily via reductions in proatherogenic lipoproteins. Thus, PPAR-α selective agonist shows a greater anti-atherosclerotic response compared to PPAR-γ and LXR agonists in diet-induced atherosclerosis-susceptible F 1B hamster. © 2010 Elsevier Ireland Ltd.
Mahajan G.B.,Piramal Life science Ltd. |
Balachandran L.,Karmaveer Bhaurao Patil College
Frontiers in Bioscience - Elite | Year: 2012
The discovery of Penicillin in 1928 and that of Streptomycin in 1943, has been pivotal to the exploration of nature as a source of new lead molecules. Globally, the microbiologist today is acknowledged as a crucial player in the drug discovery program. The microbial products, especially those from actinomycetes have been a phenomenal success for the past seven decades. Bioprospecting for new leads are often compounded by the recurrence of known antibiotics in newer microbial isolates. Despite all these deterrents, actinomycetes have proved to be a sustained mine of novel antibiotics, which selectively destroys the pathogens without affecting the host tissues. Each of these antibiotics is unique in their mode of action. Their versatility and immense economic value is something, which is extremely noteworthy. The anti-infective turn-over of over 79 billion US dollars in 2009, includes about 166 antibiotics and derivatives such as the Beta-lactam peptide antibiotics, the macrolide polyketide erythromycin, tetracyclines, aminoglycosides, daptomycin, tigecycline, most of which are produced by actinomycetes (1). Actinomycetes continue to play a highly significant role in drug discovery and development. Among the bioactive compounds that have been obtained so far from microbes, 45% are produced by actinomycetes, 38% by fungi and 17% by unicellular eubacteria (2). Further many chemically synthesized drugs owe their origin to natural sources. In this review article, we highlight the recent antibiotics from actinomycetes with emphasis on their source, structures, activity, mechanism of action and current status.
Oncotest Gmbh and PIRAMAL LIFE science Ltd | Date: 2010-11-15
PIRAMAL LIFE science Ltd | Date: 2011-08-31
The present invention provides novel compounds represented by the general formula (I): their stereoisomers, pharmaceutically acceptable salts and their pharmaceutically acceptable solvates thereof, which are useful in treating metabolic disorders related to insulin resistance or hyperglycemia. The invention also relates to a process for the manufacture of compounds of formula (I) and pharmaceutical compositions containing them.
Piramal Life science Ltd | Date: 2010-08-11
Compounds of formula 1: are disclosed, wherein V is CH