**Background**
Vitamin B12 deficiency can lead to severe hematological and neurological complications, including pernicious anemia. Beyond its nutritional role, certain forms of vitamin B12 exhibit unique pharmacological properties that are critical in emergency medicine and toxicology. Specifically, the ability to bind nitric oxide (NO) and detoxify lethal poisons such as cyanide and sodium hydrosulfide (NaSH) makes these compounds essential for treating acute poisoning and vasoplegic syndromes. Understanding the Hydroxocobalamin biological activity in these contexts is vital for developing rescue therapies for cardiovascular collapse and chemical toxicity. In this context, we will introduce a natural vitamin B12 derivative – Hydroxocobalamin.
**Definition**
Hydroxocobalamin is an injectable natural vitamin B12 (human endogenous metabolite) with the molecular formula C64H91CoN13O16P. It acts as a scavenger for cyanide and nitric oxide, effectively reducing hypotension and detoxifying various sulfur-containing toxins.
**In Vitro and In Vivo Studies**
According to the Hydroxocobalamin technical information, this compound demonstrates distinct protective effects across various models. Hydroxocobalamin in vitro studies indicate that while 1 mM acetate does not significantly improve mitochondrial respiratory states or attenuate superoxide production in cyanide-poisoned peripheral blood mononuclear cells (PBMC) and human aortic smooth muscle cells (HASMC), a concentration of 50-100 μM acetate effectively prevents hepatocyte cytotoxicity induced by NaSH in isolated rat hepatocytes.
Hydroxocobalamin In Vivo research has further validated its therapeutic potential. In LPS-treated mice and rats, a single intravenous dose of 20 mg/kg attenuated hypotension, increased plasma reactive nitrogen intermediates (RNI), and decreased mortality. In rats with cyanide poisoning induced by oral amygdalin ingestion, intravenous administration of 25-50 mg/kg over 14 days reduced blood cyanide and serum lactate levels in a dose-dependent manner, while normalizing blood pH and hemoglobin concentration. Furthermore, in adult beagle dogs with acute potassium cyanide poisoning, doses of 75-150 mg/kg significantly reduced mortality and led to rapid cardiovascular recovery within 1-3 minutes post-infusion. Additionally, an intraperitoneal dose of 0.25 mmol/kg administered 2 minutes after NaSH administration effectively prevented death in mice at 24 hours. In conclusion, Hydroxocobalamin is a potent detoxifying agent and cardiovascular stabilizer used extensively in research related to vitamin B12 deficiency and acute chemical poisoning.
Keywords
Hydroxocobalamin, 22465-48-1, Vitamin B12a, NO Synthase, Nitric oxide synthases, NOS, albino rats, beagle dogs, mice, HASMC, PBMC, hypotension, Inhibitor, inhibitor, inhibit
References
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