Suppression of Propionibacterium acnes‐stimulated proinflammatory cytokines by Chinese bayberry extracts and its active constituent myricetin in human sebocytes in vitro

Abstract

Myrica rubra Sieb. et Zucc. (Myricaceae), known as Chinese bayberry, is traditionally used as folk medicine in Asian countries. The interaction of Propionibacterium acnes signalling with sebocytes is considered important in the pathogenesis of acne. In the present study, extracts and active compounds of Chinese bayberry were used to determine chemical antioxidant activity and anti-inflammatory effects in P. acnesstimulated human SZ95 sebocytes. A high-performance liquid chromatography with electrochemical detection system was used to analyse the phenolic composition of bayberry extracts. Accordingly, the flavonols, myricitrin and myricetin, were found to be abundant in the unhydrolysed and hydrolysed extracts of Chinese bayberry fruits, respectively. The anthocyanin cyanidin-3-glucoside was also predominantly found in the unhydrolysed extracts. Quantification of human inflammatory cytokines indicated that cell-free extracts of P. acnes stimulated IL-8 and IL-6 production, which was inhibited by myricetin, rather than its glycoside or anthocyanin. Myricetin also exhibited inhibitory effects in P. acnes-stimulated gene expression of Toll-like receptor (TLR) 2 and protein phosphorylation of p70 S6 kinase. In conclusion, myricetin shows a suppressive effect on P. acnes-induced cytokine production through regulation of the TLR and mammalian target of rapamycin pathways. Myricetin goes beyond previous research findings to potentially modulate inflammatory signalling in human sebocytes. These results will be valuable in developing anti-inflammatory agents against skin acne.

Overexpression of miR-651-5p inhibits ultraviolet radiation-induced malignant biological behaviors of sebaceous gland carcinoma cells by targeting ZEB2

“…The immortalized human sebaceous gland cell line SZ95 ( 31 ) was purchased from BeNa Culture Collection (BNCC338262, BNCC, China) and cultured in Sebomed ® Basal Medium (#F8025; Biochrom, Berlin, Germany) containing 10% fetal bovine serum (FBS, #16140071; Gibco; Thermo Fisher Scientific, Inc., USA) and 5 ng/mL recombinant human epidermal growth factor (#PHG0313; Gibco; Thermo Fisher Scientific, Inc., USA) at 37 ℃ and 5% CO 2 according to a previous report ( 32 ).…”

Anthocyanin Effects in Reducing Platelet Hyperactivity and Thrombotic Risk in Type 2 Diabetes

“…Few other studies have also measured the effect of AC in lowering pro-inflammatory biomarkers, but the sample population, type of inflammatory markers, and the source of AC were different. It has been shown by other studies which implemented diverse sample populations and doses and duration of AC treatment, that AC has demonstrated more powerful impact on lowering inflammatory markers [47][48][49][50][51][52].…”

An overview of the nutritional value, health properties, and future challenges of Chinese bayberry

“…Similarly, proanthocyanidins derived from CB leaves exhibit pronounced anti-oxidant potency ( Fu et al, 2014 ), while cyanidin-3-O-glucoside extracted from CB fruit can protect neonatal porcine islets against reactive oxygen species-induced injury ( Li et al, 2017a ). Cyanidin-3-O-glucoside and myricetin additionally exhibit anti-inflammatory activity when used to treat P. acnes -stimulated human SZ95 sebocytes, making them promising modulators of inflammatory signaling pathways in the treatment of skin acne ( Chen et al, 2019 ). Phenolic-rich extracts derived from CB can additionally prevent protein glycation and advanced glycation end-products formation, in addition to exhibiting anti-aging properties ( Zhang et al, 2021 ) ( Table 2 ).…”