In this study, we have investigated the effect of an antioxidant probiotic pretreatment toward an overdose of diclofenac in rats (100 mg/kg bw). Rats were treated daily with the probiotic Streptococcus salivarius St.sa (10 9 CFU) during seven successive days and then received a single treatment with diclofenac overdose in distilled water. Liver transaminases (alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase), histology, glutathione (GSH) and malondialdehyde (MDA) level were investigated. In addition, both antioxidant enzyme activity and its mRNA gene expression were studied to evaluate diclofenac hepatotoxicity. The results indicated that probiotic pretreatment reduced diclofenac-induced hepatotoxicity through enhancement of the studied hepatic markers and regulation of antioxidant enzyme expression and activity. These findings indicate that the probiotic pretreatment protects rat liver against the oxidative stress induced by diclofenac overdose.

Background: Propolis (PRS) and probiotic bacteria Lactobacillus are natural products used as dietary supplement for their therapeutic benefits. This study was performed to examine the possible hepatoprotective effect of PRS and probiotics (PRCs) against carbon tetrachloride-induced liver injury. Methods: Experimentally, intoxicated rats received 0.5 ml/kg CCl4 (i.p.) daily for six days, pretreated rats received per os PRS 100 mg/kg or PRCs 109 CFU for six days followed by a single dose of 0.5 ml/kg CCl4. Control groups received either PRS, PRCs or olive oil for six days. Then, serum biochemistry (total protein, cholesterol, triglycerides and albumin) and oxidative stress parameters were measured. Results: We showed that CCl4 treatment was associated with an increase of the serum aspartate amino transferase (AST), alanine aminotransferase (ALT), cholesterol and triglycerides levels. In parallel, serum total protein, albumin and blood sugar levels were significantly decreased. Regarding the oxidative stress parameters, catalase and glutathione S-transferase (GST) levels were lower, conversely to the lipid peroxidation (MDA). Conclusion: Our results strongly support that administration of PRS and PRCs may significantly protect liver against CCl4-induced toxicity by enhancing antioxidative stress pathway and preventing lipid peroxidation.

Many researchers are focusing on the investigation of new molecules and substances to help the body fighting oxidative stress; among them are probiotic bacteria. In this study we investigated the probiotic properties and the antioxidative activity of Lactobacillus plantarum 15 isolated from milk. Therefore, to evaluate probiotic potential of the selected strain, the antibacterial activity and resistance to acidic pH and bile salts conditions were evaluated. Moreover, several methods were used to analyze the antioxidant potential of this strain. The evaluation of probiotic properties showed that Lb. plantarum 15 resists to acidity and to bile salts (survival rate was 86.40% and 80.58%, respectively). The isolate showed a broad inhibitory activity against several bacterial strains. The antioxidant potential assessed by the DPPH method showed that Lb. plantarum 15 cells as well as the cell-free supernatant have important scavenger effect (82.65% and 72.21%, respectively). Furthermore, the strain showed a good resistance to hydrogen peroxide (76.12%), hydroxyl radicals (46.15%) and a considerable iron chelating ability (20.52 %). Thus, Lb. plantarum 15 could be effectively considered as potent antioxidant probiotic food supplement.