6-Paradol Acts as a Potential Anti-obesity Vanilloid from Grains of Paradise

Scope Grains of Paradise (GOP), the seeds of Aframomum melegueta, has anti-obesity effects. However, the mechanisms underlying the effects remain unclear. Methods and results We set up to study the anti-obesity impact and homeostatic effects of 6-paradol, a major vanilloid found in GOP, and investigated the physiological outputs and the lipometabolism-related gene in fat and liver in high-fat-induced obese mice with a comparison with structurally similar vanilloids (6-gingerol and 6-shogaol). The vanilloids were synthesized in adequate quantities for performing animal experiments and orally administered to six-week-old male mice over two weeks. We found that 6-paradol decreased body weight gain and visceral and subcutaneous fats in two weeks, whereas 6-gingerol and 6-shogaol had no effect. Additionally, 6-paradol suppressed the hepatic cholesterol and triglyceride and significantly decreased the gene expression related to fatty acid synthesis, lipid transportation, and adipocyte differentiation in both liver and adipose tissue. Moreover, phosphorylation of AMP-activated protein kinase (AMPK) that greatly contributes to lipometabolism was promoted by 6-gingerol but not 6-paradol. Conclusion These results suggest that 6-paradol regulates several obesity-related genes in an AMPK-independent manner. Therefore, it could be the principal active vanilloid in GOP giving it anti-obesity properties with a different mechanism. This article is protected by copyright. All rights reserved.