Polyphenol Compounds Attenuate High‐Dose PUFA‐Induced Oxidative Damage in Adipocytes

Abstract

Although polyunsaturated fatty acids (PUFAs) are beneficial fatty acids, their excessive deposition can easily lead to lipid‐induced oxidation damage. It has recently been shown that diets rich in particular polyphenols may improve the oxidative status of tissues with high PUFA content. However, the underlying mechanism for this remains elusive. Therefore, a model is created of high‐dose PUFA injury in adipocytes, which investigates the effects of rosmarinic acid (RA) and caffeic acid (CA) on the alleviation of oxidative damage induced by high doses of PUFAs. It is observed that high‐dose linolenic acids (ALA) enhance lipid oxidation, inflammation, and autophagy in adipocytes. However, RA and CA attenuate the high‐dose ALA‐enhanced expression of inflammatory cytokines and microtubule‐associated protein 1, light chain 3, beta (MAP1LC3B). In addition, they reduce the intracellular levels of malondialdehyde (MDA) that are elevated by high doses of ALA, and modulate the activities of superoxide dismutase (SOD), catalase antioxidant (CAT), and glutathione peroxidase (GSH‐Px) enzymes. The protective effects of RA and CA on adipocyte oxidative stress are in part associated with their capacity to improve the activities of antioxidant enzymes and exert free radical‐scavenging activity. Collectively, these results suggest that RA and CA may have potential benefits in protecting adipose cells from high‐dose PUFA‐induced oxidative damage.Practical Applications: It is known that a diet rich in PUFAs has beneficial effects on cardiovascular disease. However, an accumulation of unsaturated fatty acids in tissues is more susceptible to lipid oxidation. In this study, it is found that polyphenols have the potential to protect adipose cells from high‐dose PUFAs‐induced damage. It has also been suggested that the consumption of a diet enriched in polyphenols could be beneficial for the prevention of lipid peroxidation and maintaining the balance between oxidative and anti‐oxidative processes.Polyphenols suppress the formation of lipid peroxy radical species. The process of lipid peroxidation consists of initiation, propagation, and termination. In the termination reaction, polyphenols may donate a hydrogen atom to the lipid radical, resulting in the termination of lipid peroxy radical species formation. In addition, polyphenols may improve the activity of antioxidant enzymes, thereby suppressing the formation of lipid peroxy radical species.