Molecular Toxinology Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Assam, 784028, India.
Molecular Ecology and Evolution at Bangor, School of Natural Sciences, Bangor University, Bangor, LL57 2UW, Gwynedd, UK.
Toxicon. 2022 Apr 30;210:66-77. doi: 10.1016/j.toxicon.2022.02.014. Epub 2022 Feb 22.
Green pit vipers, a name that can refer to several unrelated species, comprise a large group of venomous snakes found across the humid areas of tropical and sub-tropical Asia, and are responsible for most of the bite cases across this region. In India, green pit vipers belonging to several genera are prevalent in the northern and north-eastern hilly region, unrelated to species present in the peninsular region. In the present study, crude venom of representative species of green pit vipers present in the north and north-eastern hilly region of India (Trimeresurus erythrurus, T. septentrionalis, Viridovipera medoensis, and Popiea popieorum) were characterized to elucidate venom composition and venom variation. Profiling of crude venoms using SDS-PAGE and RP-HPLC methods revealed quantitative differences among the species. Further, in vitro biochemical assays reveal variable levels of phospholipase activity, coagulation activity, thrombin-like activity, fibrinogenolytic and haemolytic activity. This correlates with the pseudo-procoagulant effects on the haemostatic system of victims, which causes consumptive coagulopathy, frequently observed in patients bitten by green pit vipers. The immunoreactivity of Indian polyvalent antivenom and Thai green pit viper antivenom towards crude venoms were also evaluated by western blotting and inhibition of biochemical activities. The results exhibited poor efficacy of Indian polyvalent antivenom in neutralizing the venom toxins of crude venoms; however, Thai green pit viper antivenin (raised against the venom of Trimeresurus allbolabris, not present in India) showed higher immunoreactivity towards congeneric venoms tested. Analysis of green pit viper bite patients records from a community health centre in Assam, India, further revealed the inability of Indian polyvalent antivenom to reverse the extended coagulopathy featured.
绿林蝮，一个可指代多个不相关物种的名称，包含了一大类广泛分布于亚洲热带和亚热带潮湿地区的毒蛇，并且是该地区大多数咬伤案例的罪魁祸首。在印度，几种属的绿林蝮常见于北部和东北部丘陵地区，与半岛地区的物种无关。在本研究中，对印度北部和东北部丘陵地区的代表性绿林蝮（Trimeresurus erythrurus、T. septentrionalis、Viridovipera medoensis 和 Popiea popieorum）的粗毒液进行了表征，以阐明毒液成分和毒液变异。使用 SDS-PAGE 和 RP-HPLC 方法对粗毒液进行分析，揭示了物种之间的定量差异。此外，体外生化测定显示出不同水平的磷脂酶活性、凝血活性、类凝血酶活性、纤维蛋白原酶活性和溶血活性。这与受害者止血系统中假促凝作用相关，这种作用导致消耗性凝血障碍，经常在被绿林蝮咬伤的患者中观察到。还通过 Western blot 和生化活性抑制评估了印度多价抗蛇毒血清和泰国绿林蝮抗蛇毒血清对粗毒液的免疫反应性。结果显示，印度多价抗蛇毒血清在中和粗毒液毒素方面效果不佳；然而，泰国绿林蝮抗蛇毒血清（针对未在印度发现的 Trimeresurus allbolabris 毒液制备）对测试的同种毒液表现出更高的免疫反应性。对印度阿萨姆邦一个社区卫生中心的绿林蝮咬伤患者记录的分析进一步表明，印度多价抗蛇毒血清无法逆转特征性的凝血障碍延长。
