Effects of Catechin, Quercetin and Taxifolin on Redox Parameters and Metabolites Linked with Renal Health in Rotenone-toxified Rats.

Nephrotoxicity, with the attendant risk of progression to kidney failure, is a growing problem in many parts of the world. Current orthodox treatment options for nephrotoxicity and kidney failure are limited and there is need for alternative or complementary approaches. This study aimed at evaluating the effect of three structurally related flavonoids, catechin, quercetin and taxifolin on renal redox and metabolite biochemical disturbances in rotenone intoxicated animals. Male Wistar rats were administered 1.5 mg/kg rotenone (s.c.) for ten days followed by post-treatment with catechin (5, 10 or 20 mg/kg), quercetin (5, 10, or 20 mg/kg) and taxifolin (0.25, 0.5 or 1.0 mg/kg) (s.c.), for 3 days. Renal redox indices and levels of renal-related metabolites (creatinine, urea and uric acid) were assessed after sacrifice of animals. Catechin, quercetin and taxifolin significantly attenuated rotenone-induced effects on oxidative stress markers and metabolites linked to renal health.  Quercetin was clearly more effective than catechin. The activity demonstrated by taxifolin, despite being administered at the lowest doses, was compelling. The results highlight the potential of these phytochemicals in the management of renal dysfunction. The findings additionally suggest a correlation between the structure of the flavonoids and their activity but also indicate that additional structural considerations beyond conventionally acknowledged ones may be involved.

Rutin and quercetin show greater efficacy than nifedipin in ameliorating hemodynamic, redox, and metabolite imbalances in sodium chloride-induced hypertensive rats.

Rutin and quercetin were investigated for their effects on blood pressure and antioxidant defense system of rats fed with 8% sodium chloride-supplemented diet (high salt diet) for 6 weeks. Animals fed with high salt diet demonstrated an increase in systolic, diastolic, pulse, and mean arterial blood pressures (p < 0.05) as well as lipid peroxidation but decreases in the activities of antioxidant enzymes compared with control group. Groups post-treated with rutin and quercetin for 2 weeks showed significant reversals in the values of these indices compared with the group fed with only the high salt diet but not post-treated. The high salt diet also led to significant increase in serum glucose, urea, creatinine, triglycerides, low-density-lipoprotein, and total cholesterol concentrations. Treatment with rutin and quercetin ameliorated the effects of high salt diet on these biochemical indices. The reference standard, nifedipin was less effective than rutin and quercetin. The results of this study highlight the risk of high salt consumption on cardiovascular health and the potent antioxidant and antihypertensive property of rutin and quercetin.