Risperidone-induced metabolic dysfunction is attenuated by Curcuma longa extract administration in mice.

Antipsychotics, such as risperidone, increase food intake and induce alteration in glucose and lipid metabolism concomitantly with overweight and body fat increase, these biological abnormalities belong to the metabolic syndrome definition (high visceral adiposity, hypertriglyceridemia, hyperglycemia, low HDL-cholesterol and high blood pressure). Curcumin is a major component of traditional turmeric (Curcuma longa) which has been reported to improve lipid and glucose metabolism and to decrease weight in obese mice. We questioned the potential capacity of curcumin, contained in Curcuma longa extract (Biocurcuma™), to attenuate the risperidone-induced metabolic dysfunction. Two groups of mice were treated once a week, for 22 weeks, with intraperitoneal injection of risperidone (Risperdal) at a dose 12.5 mpk. Two other groups received intraperitoneal injection of the vehicle of Risperdal following the same schedule. Mice of one risperidone-treated groups and of one of vehicle-treated groups were fed a diet with 0.05% Biocurcuma™ (curcumin), while mice of the two other groups received the standard diet. Curcumin limited the capacity of risperidone to reduce spontaneous motricity, but failed to impede risperidone-induced increase in food intake. Curcumin did not reduce the capacity of risperidone to induce weight gain, but decreased visceral adiposity and decreased the risperidone-induced hepatomegaly, but not steatosis. Furthermore, curcumin repressed the capacity of risperidone to induce the hepatic over expression of enzymes involved in lipid metabolism (LXRα, FAS, ACC1, LPL, PPARγ, ACO, SREBP2) and decreased risperidone-induced glucose intolerance and hypertriglyceridemia. Curcumin decreased risperidone-induced increases in serum markers of hepatotoxicity (ALAT, ASAT), as well as of one major hepatic pro-inflammatory transcription factor (NFκB: p105 mRNA and p65 protein). These findings support that nutritional doses of curcumin contained in Curcuma longa extract are able to partially counteract the risperidone-induced metabolic dysfunction in mice, suggesting that curcumin ought to be tested to reduce the capacity of risperidone to induce the metabolic syndrome in human.

Paullinia pinnata extracts rich in polyphenols promote vascular relaxation via endothelium-dependent mechanisms.

Paullinia pinnata L. (Sapindaceae) is an African tropical plant whose roots and leaves are used in traditional medicine for many purposes, especially for erectile dysfunction, but its action mechanism is unknown. P. pinnata root and leaf methanolic extracts are rich in phenolic compounds. This study shows that both extracts are highly antioxidative and induce a slight transcriptional activity of peroxisome proliferator activated receptor-alpha. They also increased and decreased endothelial nitric oxide synthase and endothelin-1 mRNA levels in bovine aortic endothelial cells, respectively. In this study P. pinnata methanolic extracts in cumulative doses elicited in a dose-dependent manner the relaxation of phenylephrine precontracted isolated rat aortic rings. N-nitro-L-arginine methyl ester significantly attenuated the capacity of both extracts to induce arterial relaxation, indicating that this arterial relaxation was mediated by endothelial nitric oxide release. It could be suggested that the arterial relaxation induced by both extracts could be mainly linked to their capacities to inhibit nitric oxide oxidation through their antioxidant properties.