Impact of scorpion venom as an acute stressor on the neuroendocrine-immunological network

Abstract

Although immunomodulatory property and many other pharmaceutical applications of scorpion venom have been addressed before, no studies were reported about its application as a neuroimmunomodulator at therapeutic dose. In this study, we conceptualized the property of scorpion venom, capable of inducing the acute pain and neurotoxicity can cause acute stress resulting in the modulation of immune cells through HPA axis. The whole venom from Hottentotta rugiscutis, a widely seen scorpion in the region of eastern Karnataka, was extracted and injected a single dose of 1 mg/kg b.w. to Swiss albino mice and then erythrocytes and leukogram were measured. Whole brain AChE activity, corticosterone, cytokines and NO levels in plasma were also evaluated at various time points. Hrv didn't show any histopathological changes in the lymphoid organs and at the site of injection. However, lymphocytes and neutrophils did get altered at 2 h post-injection. Plasma corticosterone, cytokine levels such as IL-1β, IL-6, TNF-α and IL-10 and the AChE activity were significantly increased in a time-dependent manner. Based on these results, it may be predicted, Hrv's ability to cause acute stress resulted in the activation of HPA axis, which stimulates the release of glucocorticoid hormones which in turn elicits the immunomodulation of leukocytes by altering the levels of pro and anti-inflammatory cytokines. Thus, we can conclude, the impact of acute stress induced by Hrv can intercommunicate the signals between neuroendocrine-immune systems.