Estrous Cycle Cessation Caused via Activating the Apoptotic Pathway by NNSS2 Isolated from Naja naja Shedded Skin

The snake shed skin has long been used in the Chinese and Indian traditional, folk medicine for various medicinal purposes. Previously it was reported that N. naja shedded skin caused temporary cessation of the estrous cycle. Based on these reviews and reports this work was undertaken to purify, characterize bioactive compound from Naja naja shedded skin and to assess its bioactivity in animal model. The N. naja shed skin extract was subjected to thin layer chromatography, HPLC for purification to obtain active factor, and it was characterized (MALDI, CD spectral analysis, H1NMR & XRD). Purified fraction was injected subcutaneously in female Swiss albino mice. Serum progesterone, estradiol, IL-1β, TNF-α levels were assessed; histopathology of uterus and ovary was done. Uterine and ovarian apoptotic marker expressions were studied. NNSS2 was purified having molecular weight of 882.6 Dalton. It caused cessation of estrous cycle for 5 days, decreased serum progesterone, P4-E2 ratio, increased IL-1β, caspase 3,9, Bax, decreased BCL2, HSP70, HSP90 expressions and cleaved PARP. Histological studies of ovary showed immature follicles; and uterus displayed constricted structure. NNSS2 influenced reproductive cycle of female albino mice by altering hormones, cytokine profiles, apoptotic markers, and by involvement of intrinsic apoptotic pathway. This study provided a novel outline of the probable bioactive compounds present in the N. naja shedded skin.