# Molecular mechanisms of propolis in adipogenesis, lipid metabolism and white adipose tissue Browning: a systematic review of preclinical studies

## TL;DR

This review explores how propolis, a natural substance, may help reduce obesity by promoting the conversion of white fat into brown fat in preclinical studies.

## Contribution

The paper systematically reviews preclinical evidence on propolis's molecular mechanisms in regulating fat metabolism and promoting white adipose tissue browning.

## Key findings

- Propolis and its compounds modulate adipogenic transcription factors and reduce lipid accumulation in preclinical models.
- In vivo studies show propolis reduces body weight, fat accumulation, and promotes thermogenesis.
- Biomarkers of browning are increased in cellular and animal models treated with propolis.

## Abstract

White adipose tissue (WAT) browning has gained increasing attention as potential strategy for obesity management. The conversion of WAT into brown adipose tissue (BAT) enhances energy expenditure and improves metabolic health. Propolis, natural resinous substance produced by honeybees, contains bioactive compounds such as caffeic acid phenethylester, chrysin and quercetin, which are thought to regulate adipogenesis and promote WAT browning. This systematic review aimed to synthesize preclinical evidence on the molecular mechanisms by which propolis and its bioactive compounds regulate adipogenesis, lipid metabolism and the browning of white adipose tissue. We conducted a systematic search of electronic databases, including PubMed, Scopus and Google Scholar, without time restrictions, using relevant keywords related to propolis and obesity. A total of 7 preclinical studies (animal and in vitro) met the inclusion criteria. These studies indicate that propolis and its bioactive compounds, modulate adipogenic transcription factors, reduce lipid accumulation and increase expression of browning markers in cellular and animal models. Studies in vivo demonstrate reductions in body weight, fat accumulation and adipocyte differentiation, accompanied by increased thermogenesis. Preclinical evidence suggests that propolis modulates adipogenesis, lipid metabolism and WAT browning; however, clinical trials assessing mechanistic endpoints are lacking and necessary before translational recommendations can be made.