Oxidative phosphorylation arsenate inhibition

Arsenic Inorganic arsenic salts Gastrointestinal, respiratory (all mucosal surfaces), skin Predominantly soft tissues (highest in liver, kidney). Avidly bound in skin, hair, nails Cardiovascular shock, arrhythmias. CNS encephalopathy, peripheral neuropathy. Gastroenteritis pancytopenia cancer (many sites) Inhibits enzymes interferes with oxidative phosphorylation alters cell signaling, gene expression Methylation. Renal (major) sweat and feces (minor)... 

The toxicity of Sb is a function of the water solubility and the oxidation state of the Sb species under consideration. Antimony toxicity often parallels that of arsenic, although antimony salts are less readily absorbed than arsenic. It is presumed that antimony, like arsenic, complexes with sulfhydryl groups of essential enzymes and other proteins. By analogy, antimony can uncouple oxidative phosphorylation, which would inhibit the production of energy necessary for cellular functions. Antimony s trivalent compounds are more toxic than its pentavalent compounds. 

Energy generation will be inhibited because arsenate will uncouple oxidation and phosphorylation. The arsenate will establish a small futile cycle that will shuttle between 3-phosphoglycerate and l-arseno-3-phosphoglycerate. If the conditions also are anaerobic, NADH will accumulate, and NAD will become unavailable for the continuation of sustained glycolysis. 

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