Ehab M. Abdella

Brown seaweeds protect against azoxymethane-induced hepatic repercussions through up-regulation of peroxisome proliferator-activated receptor gamma and attenuation of oxidative stress

Abstract Context: Seaweeds of the genera Turbinaria and Padina have long been used as food and in traditional medicine for treating several diseases. Objective: The current study determines the protective efficacy of the brown seaweeds Turbinaria ornata (Turner) J. Agardh (Sargassaceae) and Padina pavonia (Linnaeus) J.V. Lamouroux (Dictyotaceae) against liver injury induced by azoxymethane (AOM). Materials and methods: Male Swiss mice received 10 mg/kg AOM once a week for two consecutive weeks and then 100 mg/kg daily dose of either T. ornata or P. pavonia ethanolic extract. Thirteen weeks after the first AOM administration and 24 h after the last treatment, overnight fasted mice were sacrificed and samples collected. Results: Compared with the AOM group, both T. ornata and P. pavonia significantly decreased the activity of aminotransferases and the concentration of bilirubin while increased albumin levels in the serum. The antioxidative effect of both extracts was observed from the increased activity of superoxide dismutase and glutathione peroxidase activities in the liver, both of which were decreased by AOM. Moreover, the levels of malondialdehyde and nitric oxide were reduced, and histological findings also confirmed the antihepatotoxic activity. In addition, treatment with T. ornata and P. pavonia significantly increased PPARγ and decreased NF-κB expression in the liver of AOM-administered mice. Discussion and conclusion: Our findings indicate that the protective function of T. ornata and P. pavonia on AOM-induced liver injury may be possibly exerted by multiple pathways including abolishment of inflammation and oxidative damage, and activation of PPARγ.

Protective Effects of Turbinaria ornata and Padina pavonia against Azoxymethane-Induced Colon Carcinogenesis through Modulation of PPAR Gamma, NF-κB and Oxidative Stress.

The aim of this study was to investigate the antiproliferative and protective effects of the brown seaweeds, Turbinaria ornata and Padina pavonia, against azoxymethane (AOM)‐induced colon carcinogenesis in mice. Both algal extracts showed anti‐proliferative effects on the human carcinoma cell line HCT‐116 in vitro, with T. ornata demonstrating a more potent effect. Male albino Swiss mice received intraperitoneal injections of AOM (10 mg/kg) once a week for two consecutive weeks and 100 mg/kg of either T. ornata or P. pavonia extracts. AOM‐induced mice exhibited alterations in the histological structure of the colon, elevated lipid peroxidation and nitric oxide, declined glutathione content and reduced activity of superoxide dismutase and glutathione peroxidase. In addition, AOM induced downregulation of peroxisome proliferator activated receptor gamma (PPARγ) and p53 mRNA expression, with concomitant upregulation of nuclear factor‐kappa B (NF‐κB) in colon tissue. Administration of either algal extract markedly alleviated the recorded alterations. In conclusion, the current study suggests that T. ornata and P. pavonia, through their antioxidant and anti‐inflammatory effects, are able to attenuate colon inflammation by downregulating NF‐κB expression. Furthermore, the protective effects of both algae against AOM‐initiated carcinogenesis were attributed, at least in part, to their ability to upregulate colonic PPARγ and p53 expression. Copyright

Protective effect of ellagic acid against cyclosporine A-induced histopathological, ultrastructural changes, oxidative stress, and cytogenotoxicity in albino rats

ABSTRACT Cyclosporine A (CsA) is an immunosuppressor agent, which is most frequently used in transplant surgeries and in the treatment of autoimmune diseases. This study was undertaken to investigate the protective effects of ellagic acid (EA) against CsA-induced testicular histopathology and ultrastructure changes, oxidative stress, and cytogenotoxicity in male albino rats. Rats were divided into six groups; the first group was used as a control, the second group received a subcutaneous injection of slightly alkaline solution, the third group received olive oil orally, the fourth group was injected subcutaneously with EA at a dose of 10 mg/kg b. wt./day, the fifth group was treated with CsA as oral solution at a dose of 15 mg/kg b. wt for 30 days, and the sixth group was treated with CsA simultaneously with EA. Treatment with EA simultaneously with CsA resulted in significant protection. The positive control animals taking CsA alone showed marked histopathological, ultrastructure, and genetic manifestations accompanied by an elevated content of lipid peroxidation and marked reduction of catalase (CAT), peroxidase (Px) activity, and glutathione concentration in the homogenate of testis tissues. The toxic side effects in testis and bone marrow tissues were greatly ablated with a significant reduction in lipid peroxidation level and elevation in CAT and Px activities and glutathione concentration when using EA. Thus, EA may be used in combination with CsA to improve the histopathological, oxidative stress, and cytogenotoxicity parameters of testicular toxicity induced by CsA due to its antioxidant effects.