Anti-obesity efficacy of nanoemulsion oleoresin capsicum in obese rats fed a high-fat diet

Abstract

Joo-Yeon Kim,1,* Mak-Soon Lee,1,* Sunyoon Jung,1 Hyunjin Joo,1 Chong-Tai Kim,2 In-Hwan Kim,3 Sangjin Seo,1 Soojung Oh,1 Yangha Kim11Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, Republic of Korea; 2Functional Materials Research Group, Korea Food Research Institute, Seongnam, Gyeonggi, Republic of Korea; 3Department of Food and Nutrition, Korea University, Seoul, Republic of Korea *These authors contributed equally to this workPurpose: This study determined the effects of oleoresin capsicum (OC) and nanoemulsion OC (NOC) on obesity in obese rats fed a high-fat diet.Methods: The rats were randomly separated into three groups: a high-fat (HF) diet group, HF + OC diet group, and HF + NOC diet group. All groups were fed the diet and water ad libitum for 14 weeks.Results: NOC reduced the body weight and adipose tissue mass, whereas OC did not. OC and NOC reduced mRNA levels of adipogenic genes, including peroxisome proliferator-activated receptor (PPAR)-γ, sterol regulatory element-binding protein-1c, and fatty acid-binding protein in white adipose tissue. The mRNA levels of genes related to β-oxidation or thermogenesis including PPAR-α, palmitoyltransferase-1α, and uncoupling protein-2 were increased by the OC and NOC relative to the HF group. Both OC and NOC clearly stimulated AMP-activated protein kinase (AMPK) activity. In particular, PPAR-α, palmitoyltransferase-1α, uncoupling protein-2 expression, and AMPK activity were significantly increased in the NOC group compared to in the OC group. NOC decreased glycerol-3-phosphate dehydrogenase activity whereas OC did not.Conclusion: From these results, NOC could be suggested as a potential anti-obesity agent in obese rats fed a HF diet. The effects of the NOC on obesity were associated with changes of multiple gene expression, activation of AMPK, and inhibition of glycerol-3-phosphate dehydrogenase in white adipose tissue.Keywords: oleoresin capsicum, nanoemulsion, anti-obesity, gene expression, AMP-activated protein kinase, rats