Ultraviolet radiation‐induced lipid peroxidation in liposomal membrane: Modification by capsaicin

Ultraviolet‐radiation has been reported to cause lipid peroxidation in the liposomal membrane. In the present study, treatment with capsaicin, (8‐methyl‐n‐vanillyl‐6‐nonenamide), the pungent principle of red hot pepper, was shown to modify UV‐induced lipid peroxidation in the liposomal membrane. Treatment with low doses of capsaicin (less than 0.1 μg/mL of phosphatidyl choline liposome) produced a significant increase in UV‐induced lipid peroxidation, while high doses (0.1–0.5 μg/mL of PC liposome) caused a significant decrease of UV‐induced peroxidation. These pro‐oxidant and antioxidant activities of capsaicin over UV‐induced liposomal lipid peroxidation were also comparable to experiments modulated with standard pro‐oxidant ferrous sulphate and antioxidant sodium azide. The observed dual nature of capsaisin's action on the UV‐induced lipid peroxidation of the liposomal membrane may be attributed to the previously reported “activation” followed by “desensitization” action of capsaicin on other membrane lipid systems.