Jia Fu1, Jingjuan Huang1, Man Lin1, Tingting Xie1, Tianhui You2. 1. School of Nursing, Guangdong Pharmaceutical University, Guangzhou, China; Guangzhou Key Laboratory of Construction and Application of New Drug Screening Model Systems, Guangdong Pharmaceutical University, Guangzhou, China; Key Laboratory of New Drug Discovery and Evaluation of Ordinary Universities of Guangdong Province, Guangdong Pharmaceutical University, Guangzhou, China. 2. School of Nursing, Guangdong Pharmaceutical University, Guangzhou, China; Guangzhou Key Laboratory of Construction and Application of New Drug Screening Model Systems, Guangdong Pharmaceutical University, Guangzhou, China; Key Laboratory of New Drug Discovery and Evaluation of Ordinary Universities of Guangdong Province, Guangdong Pharmaceutical University, Guangzhou, China. Electronic address: youth888cn@aliyun.com.
Abstract
BACKGROUND: For patients with diabetes mellitus, excessive and long-lasting inflammatory reactions at the wound site commonly lead to the delayed refractory wound healing. The polarization of macrophages in terms of M1 and M2 phenotypes is closely related to the production of inflammatory cytokines. Quercetin is traditionally recognized to have anti-inflammatory effect; however, whether quercetin modulates macrophage polarization from M1 to M2 and thus promotes diabetic wound healing remain unknown. MATERIALS AND METHODS: Wounded male diabetic rats were equally divided into five groups: model group, solvent control group (10% DMSO), and three drug groups treated with quercetin (Q) at concentrations of 10 mg/mL (Q-LD [low dose]), 20 mg/mL (Q-MD [medium dose]), and 40 mg/mL (Q-HD [high dose]), respectively. The anti-inflammatory effect of quercetin on diabetic wounds was observed. Immunohistochemistry and quantificational real-time polymerase chain reaction were applied to test the changes in macrophage polarization and inflammatory responses. RESULTS: The wound contraction was fastest in Q-HD group. Hematoxylin and eosin (H&E) and Masson's trichrome staining revealed that fibroblast distribution and collagen deposition in quercetin-treated groups were significantly higher than those in the model group. Immunohistochemistry tests showed more CD206-positive cells and less iNOS-positive cells in quercetin-treated groups. Furthermore, the levels of proinflammatory factors in quercetin-treated groups were lower than those in the model group, whereas the levels of the anti-inflammatory factors and angiogenesis-related factors were relatively higher. CONCLUSIONS: In short, quercetin inhibits inflammatory reactions via modulating macrophage polarization switching from M1 to M2 phenotype, thereby accelerating the diabetic wound repair.
BACKGROUND: For patients with diabetes mellitus, excessive and long-lasting inflammatory reactions at the wound site commonly lead to the delayed refractory wound healing. The polarization of macrophages in terms of M1 and M2 phenotypes is closely related to the production of inflammatory cytokines. Quercetin is traditionally recognized to have anti-inflammatory effect; however, whether quercetin modulates macrophage polarization from M1 to M2 and thus promotes diabetic wound healing remain unknown. MATERIALS AND METHODS: Wounded male diabeticrats were equally divided into five groups: model group, solvent control group (10% DMSO), and three drug groups treated with quercetin (Q) at concentrations of 10 mg/mL (Q-LD [low dose]), 20 mg/mL (Q-MD [medium dose]), and 40 mg/mL (Q-HD [high dose]), respectively. The anti-inflammatory effect of quercetin on diabetic wounds was observed. Immunohistochemistry and quantificational real-time polymerase chain reaction were applied to test the changes in macrophage polarization and inflammatory responses. RESULTS: The wound contraction was fastest in Q-HD group. Hematoxylin and eosin (H&E) and Masson's trichrome staining revealed that fibroblast distribution and collagen deposition in quercetin-treated groups were significantly higher than those in the model group. Immunohistochemistry tests showed more CD206-positive cells and less iNOS-positive cells in quercetin-treated groups. Furthermore, the levels of proinflammatory factors in quercetin-treated groups were lower than those in the model group, whereas the levels of the anti-inflammatory factors and angiogenesis-related factors were relatively higher. CONCLUSIONS: In short, quercetin inhibits inflammatory reactions via modulating macrophage polarization switching from M1 to M2 phenotype, thereby accelerating the diabetic wound repair.
Authors: Huaikai Shi; Tsun-Ho Lo; Duncan Ma; Brenton Condor; Brian Lesmana; Roxanne J Parungao; Kevin H-Y Tsai; Sarah Kim; Hsiao-Ting Chen; Pablo A Silveira; Zhe Li; Mark S Cooper; Ulla Simanainen; David J Handelsman; Peter K Maitz; Yiwei Wang Journal: Int J Mol Sci Date: 2020-08-28 Impact factor: 5.923