EFFECT OF CAPSAICIN ON PHOSPHOLIPASE A(2) ACTIVITY AND SUPEROXIDE GENERATION IN MACROPHAGES

The mechanism of inhibition of Ca2+ - triggered phospholipase A(2) (PL A(2)) activity and respiratory burst in macrophages by shown that caps aicin inhibits calcium-ionophore stimulated pro-inflammatory responses in macrophages such as generation of superoxide anion, PLA(2) activit y (IC50 = 20 uM) and membrane liquid peroxidation (IC50 = 10 uM). Both capsaicin and PLA(2) and dose dependent manner. Arachidonic acid, lin oleic acid and SDS restored capsaicin inhibited respiratory burst. Cap saicin and known PLA(2) inhibitors, dexamethasone and indomethacin, in hibited Ca2+-dependent PLA(2) activity in vitro from macrophages. Inhi bition of PLA(2) activity by capsaicin is independent of Ca2+ and subs trate concentration. Fluorescence studies studies suggest that capsaic in interacts directly with partially purified macrophage PLA(2). Final ly, the antioxidant property of capsaicin was comparable to that of bu tylated hydroxy toludine (BHT). Taken together these results show that capsaicin an antiinflammatory agent with potential clinical applicati on.