Antioxidative/oxidative effects and retarding osteoconductivity of ciprofloxacin-loaded porous polyvinyl alcohol/bioactive glass hybrid.

This study investigated the effect of bioglass (melting)-polyvinyl alcohol (BG (M)-PVA) and bioglass (melting)-polyvinyl alcohol-20 %ciprofloxacin (BG(M)-PVA-20Cip) in improving antioxidant activity and regenerating bone capacity. These composites were implanted in femoral condyles of ovariectomized Wistar rats and compared to that of controls groups. After the different period of implantation (15, 30, 60 and 90 days), the treatment of ovariectomized rats with BG(M)-PVA-20Cip showed a significantly higher malondialdehyde concentration when compared to that of BG(M)-PVA group. The superoxide dismutase, glutathione peroxidase and catalase in BG(M)-PVA-20Cip group showed significantly lower activities when compared to those in BG(M)-PVA group. So, BG(M)-PVA is more tolerated by organism than BG(M)-PVA-20Cip. Moreover, the alkaline phosphatase and acid phosphatase activities showed an excellent osteoinductive property of BG (M)-PVA. This property decreased with the presence of ciprofloxacin which is confirmed by histopathological analysis. Several physicochemical techniques showed a rapid reduction in Si and Na in one hand and an accelerator rise in Ca and P ions concentrations in other hand in BG(M)-PVA than in the BG(M)-PVA-20Cip. Therefore, the incorporation of ciprofloxacin in BG(M)-PVA is characterized by a prooxidant effect in oxidant-antioxidant balance at the beginning of treatment and a retard effect of formation of apatitic phase.

Substitution effects of a carbonated hydroxyapatite biomaterial against intoxication chloride nickel-exposed rats.

AIMS: This study aimed to investigate the potential effects of a synthetic apatite (carbonated hydroxyapatite) on the detoxification of a group of male "Wistar" rats exposed to nickel chloride. METHODS: Toxicity was evaluated by rats' bioassay of nickel chloride. Wistar rats received this metal daily by gavage for seven days (4 mg/ml nickel chloride/200 g body weight, BW). To detoxify this organism, a subcutaneous implantation of the apatite is made. RESULTS: The results revealed that exposure to nickel induced oxidative stress, disorders in the balances of ferric phosphocalcic, renal failures, liver toxicity and significant increase in nickel rates in the bones of intoxicated rats. The application of the carbonated hydroxyapatite presented in this study restored those disorders back to normal. The synthetic apatite protected the rats against the toxic effects of nickel by lowering the levels of lipid peroxidation markers and improving the activities of defense enzymes. It also amended ferric and phosphocalcic equilibriums, protected liver and kidney functions and reduced the nickel rate in the bones of the rats. Overall, the results provided strong support for the protective role of carbonated hydroxyapatite in the detoxification of rats exposed to nickel. Those beneficial effects were further confirmed by physico-chemical characterization (X-ray diffraction and infrared spectroscopy), which revealed its property of anionic and cationic substitution, thus supporting its promising candidacy for future biomedical application. CONCLUSION: The hydroxyapatite is an effective biomaterial to solve health problems, particularly detoxification against metals (nickel).