Alterations in Gc levels and complexing in septic shock.

Septic shock involves increased generation of eicosanoids from arachidonic acid. Gc (vitamin D-binding protein) has been recently found to bind the parent molecule arachidonic acid but can also complex actin released as a result of tissue damage which causes displacement of bound arachidonic acid. Possible changes in serum levels of Gc and extent of complexing were therefore investigated in patients with gram-negative sepsis. As compared to healthy controls, serum levels of Gc were significantly decreased in patients with septic shock (P less than 0.01). Moreover, the percentages of Gc circulating in complexed form were significantly increased (P less than 0.01) and correlated strongly with disease severity, with levels often greater than 90% in patients who died (normal mean 8% +/- 3). These results suggest a hitherto unsuspected role for Gc in septic shock syndrome.