linoleic-acid and capsiate

The activity of a single IP administration (15 or 30 mg/Kg body weight) of vanillyl nonanoate, a simplified analog of capsiate, on ferric nitrilotriacetate (Fe-NTA)-mediated oxidative damage was investigated. A sub-lethal dose of Fe-NTA (15 mg Fe/Kg body weight) was administered IP to rats; animals were sacrificed, and kidney and plasma were collected 1 h after injection. In response to the Fe-NTA administration, a reduction of the levels of total lipids, total unsaturated fatty acids and cholesterol was observed, accompanied by a rise in the concentrations of malondialdehyde (MDA), conjugated dienes fatty acids hydroperoxides and 7-ketocholesterol in plasma and kidney 1 h after administration. A pre-treatment with synthetic capsiate (SCPT) showed remarkable protective effect on the reduction of the levels of total lipids, total unsaturated fatty acids and cholesterol, and the cellular antioxidant vitamin E, inhibiting the increase of MDA, conjugated dienes fatty acids hydroperoxides and 7-ketocholesterol in the plasma and kidney. The protective effect of SCPT and two analogues (vanillyl alcohol and vanillin) during the linoleic acid and cholesterol oxidation was investigated in in vitro systems, providing evidence of definite structure-activity relationships.

Topics: Analysis of Variance; Animals; Antioxidants; Body Weight; Capsaicin; Cholesterol; Chromatography, High Pressure Liquid; Fatty Acids; Ferric Compounds; Hydrogen Peroxide; Ketocholesterols; Kidney; Linoleic Acid; Lipid Peroxidation; Lipids; Malondialdehyde; Models, Chemical; Models, Statistical; Mutagens; Nitrilotriacetic Acid; Oxidative Stress; Oxygen; Rats; Rats, Wistar; Structure-Activity Relationship; Time Factors; Vanillic Acid

Hot peppers are a good source of dietary antioxidants, encompassing, apart from widespread compounds (flavonoids, phenolic acids, carotenoids, vitamin A, ascorbic acid, tocopherols), also specific constituents such as the pungent capsaicinoids (capsaicin, dihydrocapsaicin, and related analogues). We have shown that capsinoids also show remarkable antioxidant activity. These benign analogues of capsaicin could protect linoleic acid against free radical attack in simple in vitro systems, inhibiting both its autoxidation and its iron- or EDTA-mediated oxidation. These properties were retained in some simple synthetic analogues (vanillyl nonanoate and its dimerization products). Capsiate, dihydrocapsiate, and their analogues were devoid of pro-oxidant activity and showed a highly significant antioxidant activity in all systems investigated. Vanillyl nonanoate, a simple capsinoid mimic, was also tested on cell cultures for cytotoxic activity and the capacity to inhibit FeCl(3)-induced oxidation.

Topics: Antioxidants; Capsaicin; Capsicum; Cell Death; Cell Line; Embryo, Mammalian; Fibroblasts; Fruit; Humans; Linoleic Acid; Oxidation-Reduction