Good news! Probably, many people in Western countries have no or little idea how much snake bites are still a problem in the rest of the world.
"The anticoagulant heparin could be repurposed as a cheap and effective drug to treat cobra bites across Asia and Africa. According to the World Health Organization (WHO), up to 2 million people are envenomed by snakes each year in Asia, while in Africa there are an estimated 435,000 to 580,000 snake bites annually that need treatment.
New Australian research has found the drug can prevent cobra-venom induced necrosis in human cells and mice. Necrosis, the death of tissue around the bite, cannot currently be treated with available antivenoms. ...
They showed heparin treatment could promote human cell survival and inhibit cell death after exposure to different cobra venoms, including the African red (Naja pallida) and black-necked (Naja nigricollis) spitting cobra, the monocled cobra (Naja kaouthia), the Chinese cobra (Naja atra) and the Indian spectacled cobra (Naja naja). ..."
From the editor's summary and abstract:
"Editor’s summary
Snakebite is considered a neglected tropical disease by the World Health Organization, and although antibody-based antivenoms exist, they are species specific, are expensive, and require cold storage as well as intravenous administration in a health care setting. Here, Du and colleagues conducted a whole-genome CRISPR knockout screen to identify genes required for spitting cobra venom cytotoxicity. This screen highlighted genes involved in proteoglycan biosynthesis, suggesting that heparinoids could potentially block spitting cobra venom cytotoxicity. The heparinoid tinzaparin, given subcutaneously at the time of intradermal venom injection, effectively reduced the size of the resulting dermonecrotic lesions in mice, supporting the further evaluation of this drug for the treatment of local tissue damage from spitting cobra envenoming. ...
Abstract
Snakebites affect about 1.8 million people annually. The current standard of care involves antibody-based antivenoms, which can be difficult to access and are generally not effective against local tissue injury, the primary cause of morbidity. Here, we used a pooled whole-genome CRISPR knockout screen to define human genes that, when targeted, modify cell responses to spitting cobra venoms. A large portion of modifying genes that conferred resistance to venom cytotoxicity was found to control proteoglycan biosynthesis, including EXT1, B4GALT7, EXT2, EXTL3, XYLT2, NDST1, and SLC35B2, which we validated independently. This finding suggested heparinoids as possible inhibitors. Heparinoids prevented venom cytotoxicity through binding to three-finger cytotoxins, and the US Food and Drug Administration–approved heparinoid tinzaparin was found to reduce tissue damage in mice when given via a medically relevant route and dose. Overall, our systematic molecular dissection of cobra venom cytotoxicity provides insight into how we can better treat cobra snakebite envenoming."
Molecular dissection of cobra venom highlights heparinoids as an antidote for spitting cobra envenoming (open access)
Fig. 5. Snake venom–induced dermonecrosis is inhibited by heparinoids in vivo.
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