A nerve growth factor from the venom of Chinese cobra (Naja naja atra) and its effects on male reproductive system in rats

Seasonal expressions of nerve growth factor (NGF), and its receptor TrkA and p75 in the scent glands of muskrats (Ondatra zibethicus)

NGF, also known as nerve growth factor, is crucial for the survival and differentiation of the nervous system, in addition to being involved in a number of non-neuronal systems. The aim of this work was to investigate the immunolocalization and expression patterns of NGF, its receptor, tyrosine kinase receptor A (TrkA), and p75 in the scent glands of muskrats (Ondatra zibethicus) throughout the breeding and non-breeding seasons. The scent gland mass showed considerable seasonal variations, with higher values during the breeding season and comparatively lower levels during the non-breeding season. While no immunostaining was observed in the interstitial cells, NGF, TrkA, and p75 were immunolocalized in the scent glandular cells and epithelial cells during both breeding and non-breeding seasons. NGF, TrkA, and p75 protein and mRNA expression levels were higher in the scent glands during breeding season compared to the non-breeding season. Circulating levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T), and T in the scent gland were all significantly higher throughout the breeding season. The relative levels of the hormones in the plasma and the scent glands as well as NGF, TrkA, and p75 were positively associated with each other. Additionally, transcriptome analysis of the scent glands revealed that differentially expressed genes may be linked to steroid biosynthesis, the estrogen signaling pathway, and neurotransmitter transmembrane transporter function. These results suggest a potential role for NGF, TrkA, and p75 in controlling seasonal variations in the muskrats' scent gland functioning.

In Vivo Toxicity Profile of NN-32 and Nanogold Conjugated GNP-NN-32 from Indian Spectacled Cobra Venom

BACKGROUND

NN-32 toxin, which was obtained from Naja naja venom and showed cytotoxicity on cancer cell lines. As the toxicity of NN-32 is the main hurdle in the process of drug development; hence, we have conjugated NN-32 toxin with gold nanoparticles (GNP-NN-32) in order to decrease the toxicity of NN-32 without reducing its efficacy, GNP-NN-32 alleviated the toxicity of NN-32 in in vitro studies during the course of earlier studies. In continuation, we are evaluating in vivo toxicity profile of NN-32 and GNP-NN-32 in the present study.

OBJECTIVE

To study in vivo toxicity profile of NN-32 and nanogold conjugated GNP-NN-32 from Naja naja venom.

MATERIALS AND METHODS

We have carried out in vivo acute toxicity study to determine LD50 dose of GNP-NN-32, in vivo sub-chronic toxicity for 30 days, haematology, serum biochemical parameters and histopathology study on various mice tissues and in vitro cellular and tissue toxicity studies.

RESULTS

The LD50 dose of GNP-NN-32 was found to be 2.58 mg/kg (i.p.) in Swiss male albino mice. In vivo sub-chronic toxicity showed significantly reduced toxicity of GNP-NN-32 as compared to NN-32 alone.

DISCUSSION

In vitro cellular toxicity studies on human lymphocyte and mouse peritoneal macrophage showed significant inhibition of cells by NN-32 alone.

CONCLUSION

Conjugated GNP-NN-32 toxin showed less in vivo toxicity as compared to pure NN-32.

Anti-Inflammatory and Immune Regulatory Actions of Naja naja atra Venom

Naja naja atra venom (NNAV) is composed of various proteins, peptides, and enzymes with different biological and pharmacological functions. A number of previous studies have reported that NNAV exerts potent analgesic effects on various animal models of pain. The clinical studies using whole venom or active components have confirmed that NNAV is an effective and safe medicine for treatment of chronic pain. Furthermore, recent studies have demonstrated that NNAV has anti-inflammatory and immune regulatory actions in vitro and in vivo. In this review article, we summarize recent studies of NNAV and its components on inflammation and immunity. The main new findings in NNAV research show that it may enhance innate and humoral immune responses while suppressing T lymphocytes-mediated cellular immunity, thus suggesting that NNAV and its active components may have therapeutic values in the treatment of inflammatory and autoimmune diseases.

Two-step chromatographic method for separation and purification of nerve growth factor from venom of Chinese cobra

By selecting the different combination schemes, a simple, fast and highly efficient method for separation and purification of nerve growth factor (NGF) from venom of Chinese cobra is reported in this paper. This purification process consists of a two-step chromatographic separation on DEAE-Sepharose F.F. anion-exchange medium followed by a Sephadex G-50 gel filtration. On reducing and non-reducing sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), the nerve growth factor obtained with this process proved to be homogeneous and its molecular weight was separately estimated to be approximately 14.5 and 29.0kD, which was consistent with that reported in literature; and on high performance size-exclusion chromatography and reversed-phase chromatography, its purity was about 99%. The yield of this purification method was 0.51% and the nerve growth factor obtained had the activity of eliciting neurite outgrowth from chick embryonic dorsal root ganglia. The optimum concentration of nerve growth factor was 5-100ng/ml and the minimal concentration eliciting neurite outgrowth from chick embryonic dorsal root ganglia was 5.0 ng/ml.