Portulaca oleracea aqueous extract reduces oxidative stress in erythrocytes and tissues, in rats fed enriched-cholesterol diet -

Objective: The aim of this study was to determine the effect of aqueous extract of Portulaca oleracea (Po) on lipid peroxidation as well as antioxidant enzymes activities in erythrocytes and tissues, in hypercholesterolemic rat. Methods: Male Wistar rats were fed on 1% cholesterol-enriched diet for 10 days, and were divided into two groups fed the same diet supplemented (Po-HC) or not (HC) with Po (0.5%) for four weeks. Results: Thiobarbituric acid reactive substances were significantly decreased in erythrocytes (-48%), adipose tissue (-37%) and heart (-37%) in Po-HC. Superoxide dismutase activity in erythrocytes, liver, muscle, heart and kidney was respectively, 1.2-, 1.3-, 1.2-, 1.5- and 1.2-fold higher in Po-HC group. Catalase activity in erythrocytes, liver and heart was respectively, 1.6-, 1.7- and 1.5-fold higher in Po-HC. Glutathione peroxidase activity was 1.2-fold increased in adipose tissue, whereas that of glutathione reductase was respectively 1.4 and 1.6-fold increased in adipose tissue and liver. Conclusion: Po is able to reduce oxidative stress in hypercholesterolemic rats by decreasing the lipid peroxidation and increasing the antioxidant enzymes activities of erythrocytes and tissues. The high content of phytoconstituents present in Po as flavonoids, alkaloids, omega-3 fatty acids, β-carotene, vitamin C, saponins and tannins are considered to be responsible for this effect.