Suniti Misra

Bio: Suniti Misra is an academic researcher from University of Calcutta. The author has contributed to research in topics: Sterol & Wax. The author has an hindex of 10, co-authored 16 publications receiving 403 citations. Previous affiliations of Suniti Misra include Bose Institute.

Targeted disruption of hormone-sensitive lipase results in male sterility and adipocyte hypertrophy, but not in obesity

Abstract: Hormone-sensitive lipase (HSL) is known to mediate the hydrolysis not only of triacylglycerol stored in adipose tissue but also of cholesterol esters in the adrenals, ovaries, testes, and macrophages. To elucidate its precise role in the development of obesity and steroidogenesis, we generated HSL knockout mice by homologous recombination in embryonic stem cells. Mice homozygous for the mutant HSL allele (HSL−/−) were superficially normal except that the males were sterile because of oligospermia. HSL−/− mice did not have hypogonadism or adrenal insufficiency. Instead, the testes completely lacked neutral cholesterol ester hydrolase (NCEH) activities and contained increased amounts of cholesterol ester. Many epithelial cells in the seminiferous tubules were vacuolated. NCEH activities were completely absent from both brown adipose tissue (BAT) and white adipose tissue (WAT) in HSL−/− mice. Consistently, adipocytes were significantly enlarged in the BAT (5-fold) and, to a lesser extent in the WAT (2-fold), supporting the concept that the hydrolysis of triacylglycerol was, at least in part, impaired in HSL−/− mice. The BAT mass was increased by 1.65-fold, but the WAT mass remained unchanged. Discrepancy of the size differences between cell and tissue suggests the heterogeneity of adipocytes. Despite these morphological changes, HSL−/− mice were neither obese nor cold sensitive. Furthermore, WAT from HSL−/− mice retained 40% of triacylglycerol lipase activities compared with the wild-type WAT. In conclusion, HSL is required for spermatogenesis but is not the only enzyme that mediates the hydrolysis of triacylglycerol stored in adipocytes.

Bioactivities, bioactive compounds and chemical constituents of mangrove plants

Abstract: This review article presents the traditional and medicinal uses, and examines recent investigations on the biological activities of extracts, and chemicals identified from mangroves and mangal associates. Metabolites identified from mangrove plants are classified according to ‘chemical classes’, and some of their structures are illustrated. The article also presents some of the functions of the chemicals present and attempt to emphasize and create an awareness of the great of potential mangroves and mangal associates possess as a source of novel agrochemicals, compounds of medicinal value, and a new source of many already known biologically active compounds.