Résumé:
The present study was conducted to evaluate the protective effects and biological properties of the two endemic plants P. coronopifolia and G. reboudiana. The ethyl acetate acetate and nbutanol extracts of the P. coronopifolia plant as well as the metanolic extract of the G. reboudiana plant show richness in phenolic compounds and particularly flavonoids. These compounds provided a very important total antioxidant activity compared to standards antioxidant. This activity is justified in vitro by the reducing power and the large trapping capacity of the ROS, metal chelation, inhibition of lipid peroxidation, and plasmid DNA protection against oxidative damage induced by ROS. Thus, a potent antiproliferative activity of higher concentration has been proven in our various extracts, and especially in the extracts examined from the plant P. coronopifolia against the C6 and HeLa cancer cell lines. Another study was carried out in order to prove the in vivo antioxidant effect and the protective effect of these extracts against functional and structural alterations in livers, kidneys and hearts following PCP-induced toxicity in adult rats (with a dose of 20 mg / kg/ day during two weeks). These extracts act on the maintenance of the antioxidant system against xenobiotics. In addition, PCP treatment caused damage to the electrical system in cells membranes via a significant increase in MDA levels, a decreased GPx activity, a decreased GSH levels and a significant disruption of serum biochemical parameters (increased levels of AST, ALT, total bilirubin, urea, creatine, cholesterol and triglycerides). Pre-treatment of rats with n-butanol extracts of the P. coronopifolia plant and metanolic extract of the G. reboudiana showed that they are able to normalize the MDA reduced glutathione levels and GPx activities (of liver, kidney and heart) and capable to regularise the biochemical parameters in serums of PCP-treated rats. Pretreatment with these extracts has shown that they can act as radical chain terminators that converts reactive free radicals into stable, non-reactive products, and also as chemo-protectors against cellular oxidative damage (in liver, kidney and heart cells) induced by the PCP-treatment. Following our in vitro and in vivo studies, a histological study was carried out to confirm their protective effects against PCP-induced toxicity, by protecting the architecture of liver, kidney and heart and decreasing the functional and structural alterations of these organs. Our extracts showed strong antioxidant activity, DNA-protective capacity, high-potency anticancer effects and protective effects against PCP-induced toxicity in Witar Albinos rats.
