The Effect of Royal Jelly and Tocotrienol-rich Fraction Along With Calorie Restriction on Hypothalamic Endoplasmic Reticulum Stress and Adipose Tissue Inflammation in Diet-induced Obese Rats

Abstract

<jats:title>Abstract</jats:title> <jats:p>Objectives Endoplasmic reticulum (ER) stress causes adipose tissue dysfunction and chronic inflammation in obesity. Royal jelly (RJ) and tocotrienol-rich fraction (TRF) are reported to ameliorate inflammation. However, the improving effects of RJ and TRF on inflammation from ER stress modulating view have not been assessed so far. Hence, we investigated the effect of RJ and TRF on ER stress and some adipose tissue-derived inflammatory markers in the high-fat diet (HFD)-induced obesity. Wistar obese rats randomly allocated into 5 groups: HFD, calorie restriction diet (CRD), RJ + CRD, TRF + CRD, RJ + TRF + CRD. After 8-week intervention, adipose tissues and hypothalamus were dissected and serum was collected. Results RJ reduced glucose-regulated protein-78 (GRP78) expression as ER stress indicator in WAT and hypothalamus compared to CRD. Beside RJ diminished the expression of inflammatory markers in white adipose tissue (WAT) and also decreased the serum concentration of them. TRF reduced inflammatory markers in the serum of obese rats but the effect of TRF on ER stress was not remarkable. Overall, RJ decreased WAT and hypothalamic ER stress and diminished secretion of inflammatory markers of WAT in obesity. Thereby RJ has protective effect against adipose tissue dysfunction and inflammation then suggested as a therapeutic approach to reduce some obesity-related complications.</jats:p>