Evaluation of the effects of extracts of Maytenus imbricata (Celastraceae) on the treatment of inflammatory and metabolic dysfunction induced by high-refined carbohydrate diet.

The Maytenus genus is a member of the Celastraceae family. Numerous medicinal uses were assigned to species of this genus, with the use of roots, bark, and leaves for the treatment of gastric ulcers, as anti-inflammatory, analgesic, antiallergic, antitumor, among others. Several studies have demonstrated that natural products derived from plants have an important role in the prevention and treatment of obesity. Accordingly, we evaluated the effect of Maytenus imbricata extracts in the treatment of obesity induced by diet rich in refined carbohydrate (HC). BALB/c mice were fed chow or HC diet for 8 weeks. At the beginning of the 9th week, the HC group was subdivided into three groups: (i) group of animals that continued to consume only HC diet; (ii) the group of animals fed HC diet supplemented with ethyl acetate extract of M. imbricata roots (HC + EAE); (iii) the group of animals fed HC diet supplemented with extract in hexane/ethyl ether (HC + HEE). The period of extracts supplementation was 4 weeks. It was observed that EAE and EHE when added to the HC diet modulated the metabolic and inflammatory changes, such as: reduced the adipocytes area, improved glucose intolerance, reduced the levels of triglycerides and resistin in serum, and the number of total leukocytes in blood. In the epididymal adipose tissue, the extracts reduced proinflammatory mediators' concentration. According to the results, it was concluded that the species Maytenus imbricata has the potential to be used for the treatment of obesity.

Tingenone, a pentacyclic triterpene, induces peripheral antinociception due to cannabinoid receptors activation in mice.

Several works have shown that triterpenes induce peripheral antinociception by activation of cannabinoid receptors and endocannabinoids; besides, several research groups have reported activation of cannabinoid receptors in peripheral antinociception. The aim of this study was to assess the involvement of the cannabinoid system in the antinociceptive effect induced by tingenone against hyperalgesia evoked by prostaglandin E2 (PGE2) at peripheral level. The paw pressure test was used and the hyperalgesia was induced by intraplantar injection of PGE2 (2 µg/paw). All drugs were injected subcutaneously in the hind paws of male Swiss mice. Tingenone (200 µg/paw) administered into the right hind paw induced a local antinociceptive effect, that was antagonized by AM630, a selective antagonist to CB2 cannabinoid receptor. AM251, a selective antagonist to CB1 cannabinoid receptor, did not alter the peripheral antinociceptive effect of tingenone. MAFP, a fatty acid amide hydrolase (FAAH) inhibitor; VDM11, an anandamide reuptake inhibitor; and JZL184, monoacylglycerol lipase (MAGL) inhibitor did not potentiate the peripheral antinociceptive effect of the lower dose of tingenone (50 µg/paw). The results suggest that tingenone induced a peripheral antinociceptive effect via cannabinoid receptor activation. Therefore, this study suggests a pharmacological potential for a new analgesic drug.