RESUMO
Naja atra bites often result in immediate and severe illness. The venom of N. atra contains a complex mixture of toxins that can cause significant damage to the patient's skin tissue. If left untreated, this condition can progress to localized necrosis, potentially resulting in impairment or even amputation in severe cases. Despite the known effects of the venom, the exact mechanisms underlying this tissue necrosis are not fully understood. This study aimed to investigate the protein components responsible for tissue necrosis induced by N. atra venom at both the organism-wide and molecular levels. To achieve this, venom was injected into Bama miniature pigs to cause ulcers, and exudate samples were collected at various time points after injection. Label-free proteomics analysis identified 1119, 1016, 938, 864, and 855 proteins in the exudate at 6, 12, 24, 36, and 48 h post-injection, respectively. Further analysis revealed 431 differentially expressed proteins, with S100A8, MMP-2, MIF, and IDH2 identified as proteins associated with local tissue necrosis. In this study, we established a Bama miniature pig model for N. atra venom injection and performed proteomic analysis of the wound exudate, which provides important insights into the molecular pathology of snakebite-induced tissue necrosis and potential theoretical bases for clinical treatment. Proteomic data from this study can be accessed through ProteomeXchange using the identifier PXD052498.
RESUMO
Background: Bungarus multicinctus is one of the most dangerous venomous snakes prone to cardiopulmonary damage with extremely high mortality. In our previous work, we found that glutamine (Gln) and glutamine synthetase (GS) in pig serum were significantly reduced after Bungarus multicinctus bite. In the present study, to explore whether there is a link between the pathogenesis of cardiopulmonary injury and Gln metabolic changes induced by Bungarus multicinctus venom. We investigated the effect of Gln supplementation on the lung and heart function after snakebite. Methods: We supplemented different concentrations of Gln to mice that were envenomated by Bungarus multicinctus to observe the biological behavior, survival rate, hematological and pathological changes. Gln was supplemented immediately or one hour after the venom injection, and then changes in Gln metabolism were analyzed. Subsequently, to further explore the protective mechanism of glutamine on tissue damage, we measured the expression of heat-shock protein70 (HSP70), NF-κB P65, P53/PUMA by western blotting and real-time polymerase in the lung and heart. Results: Gln supplementation delayed the envenoming symptoms, reduced mortality, and alleviated the histopathological changes in the heart and lung of mice bitten by Bungarus multicinctus. Additionally, Gln increased the activity of glutamine synthetase (GS), glutamate dehydrogenase (GDH) and glutaminase (GLS) in serum. It also balanced the transporter SLC7A11 expression in heart and lung tissues. Bungarus multicinctus venom induced the NF-κB nuclear translocation in the lung, while the HO-1 expression was suppressed. At the same time, venom activated the P53/PUMA signaling pathway and the BAX expression in the heart. Gln treatment reversed the above phenomenon and increased HSP70 expression. Conclusion: Gln alleviated the glutamine metabolism disorder and cardiopulmonary damage caused by Bungarus multicinctus venom. It may protect lungs and heart against venom by promoting the expression of HSP70, inhibiting the activation of NF-κB and P53/PUMA, thereby delaying the process of snake venom and reducing mortality. The present results indicate that Gln could be a potential treatment for Bungarus multicinctus bite.