Role of Dietary Polyphenols in Adipose Tissue Browning: A Narrative Review

Abstract

<jats:sec> <jats:title>:</jats:title> <jats:p>Lifestyle modifications such as energy restriction and increased physical activity are highly effective in the management of obesity. However, adherence to these therapeutic approaches is poor. On the other hand, synthetic drugs used for obesity control are plagued by adverse effects. Despite these failures, adipose tissue is still an attractive therapeutic target for novel molecules, and thus, the characterisation of new and safer anti-obesity drugs is of significant interest. For this reason, in recent years, phenolic constituents of diverse plants have drawn much attention due to their health-promoting properties, opening new research lines related to brown adipose tissue activation and white adipose tissue (WAT) browning. The goal is to increase energy expenditure levels through thermogenic activity activation by multiple factors, like polyphenols. The suggested mechanisms by which polyphenols can modulate thermogenesis include Nor-epinephrine/Catechol-O-Methyl-Transferase (NE/COMT) inhibition, PPARγ co-activator alpha (PGC-1α)-dependent pathways activation, mitochondrial biogenesis, among others. Although polyphenols such as quercetin, catechins, chrysin, luteolin, curcumin, resveratrol, gallic acid, and lignans have shown a positive effect on Non-Shivering Thermogenesis and WAT browning, most of them have only been active in murine models or in vitro systems, and their reproducibility in humans has to be proved. Probably in the future, an approach that includes these compounds as part of the nutritional regime in conjunction with physical exercise, pharmacological and surgical therapy, would allow modulating a pathophysiological mechanism that is still elusive.</jats:p> </jats:sec>

Madecassoside Inhibits Body Weight Gain via Modulating SIRT1-AMPK Signaling Pathway and Activating Genes Related to Thermogenesis

“…Obesity can be effectively suppressed by inhibiting the differentiation of adipocytes or promoting the decomposition of adipocytes. Moreover, it is also essential to activate brown adipose tissue and browning of white adipose tissue for anti-obesity treatment ( 26 – 28 ). Our experiment revealed that MA treatment can inhibit weight gain of KKay mice, and it may be at least partially mediated by the following three mechanisms:…”

Is Propolis a Potential Anti-Obesogenic Agent for Obesity?

“…Catechins are polyphenols that have been claimed to have strong thermogenic and anti-obesogenic effects. Activation of PGC-1-dependent pathways, norepinephrine/catechol-O-methyl-transferase (NE/COMT) inhibition, and mitochondrial biogenesis activation have all been linked to catechins’ ability to influence thermogenesis [ 67 , 68 ]. By inhibiting COMT, a protein that is present in almost all tissues, catechins have been shown to stop the breakdown of catecholamines like norepinephrine.…”

Diet-Derived Antioxidants and Their Role in Inflammation, Obesity and Gut Microbiota Modulation

“…Thanks to these activities, cells produce energy with greater efficiency, and the replacement of defective mitochondria (notoriously associated with aging diseases) promotes energy expenditure, increasing lipid oxidation and promoting thermogenesis [ 52 ]. Thermogenesis could also be promoted by inhibiting noradrenaline degradation at the BAT-synapse level, due to the fact that the COMT enzyme, which catabolizes this catecholamine, is inhibited by some polyphenols [ 53 ].…”