EGCG Restores Keratinocyte Autophagy to Promote Diabetic Wound Healing through the AMPK/ULK1 Pathway

Chao Tian; Yuchao Feng; Tianhua Chen; Zuyang Zhang; Xiaojie He; Liangdong Jiang; Mingjiang Liu

doi:10.31083/j.fbl2812324

Frontiers in Bioscience-Landmark (Dec 2023)

EGCG Restores Keratinocyte Autophagy to Promote Diabetic Wound Healing through the AMPK/ULK1 Pathway

Chao Tian,
Yuchao Feng,
Tianhua Chen,
Zuyang Zhang,
Xiaojie He,
Liangdong Jiang,
Mingjiang Liu

Affiliations

Chao Tian: Department of Orthopaedics, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, 410004 Changsha, Hunan, China
Yuchao Feng: Department of Orthopaedics, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, 410004 Changsha, Hunan, China
Tianhua Chen: Department of Orthopaedics, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, 410004 Changsha, Hunan, China
Zuyang Zhang: Department of Orthopaedics, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, 410004 Changsha, Hunan, China
Xiaojie He: Institute of Pediatrics, Laboratory of Pediatric Nephrology, Central South University, 410011 Changsha, Hunan, China
Liangdong Jiang: Department of Orthopaedics, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, 410004 Changsha, Hunan, China
Mingjiang Liu: Department of Orthopaedics, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, 410004 Changsha, Hunan, China

DOI: https://doi.org/10.31083/j.fbl2812324
Journal volume & issue: Vol. 28, no. 12
p. 324

Abstract

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Background: Delayed wound healing, a common problem in patients with diabetes mellitus (DM), is associated with impaired keratinocyte autophagy. Epigallocatechin gallate (EGCG), a catechin, has been proven to promote diabetic wound healing. This study aims to explore the therapeutic mechanism of EGCG on diabetic wound healing. Methods: High glucose (HG)-induced keratinocytes and streptozotocin (STZ)-induced DM rats were prepared and intervened with EGCG to examine its therapeutic effects in in vivo and in vitro settings. The AMPK inhibitor, Compound C, was utilized to determine whether EGCG exerted its therapeutic effects through the AMPK/ULK1 pathway. Results: In vitro, EGCG improved HG-induced autophagy impairment in keratinocytes by increasing LC3II/LC3I, Becline1, and ATG5 levels and decreasing p62 level. Mechanically, EGCG activated the AMPK/ULK1 pathway, thereby promoting keratinocyte autophagy through the phosphorylation of AMPK and ULK1. Notably, EGCG promoted the proliferation, migration, synthesis and release of C-C motif chemokine ligand 2 (CCL2) in HG-treated keratinocytes. Furthermore, EGCG indirectly promoted the activation of fibroblasts, as evidenced by increased alpha-smooth muscle actin (α-SMA) and Collagen I levels. In vivo, EGCG promoted wound healing in DM rats, primarily by reducing inflammatory infiltration and increasing granulation tissue to promote wound epithelialization. Besides, EGCG promoted ATG5, KRT10, KRT14, TGF-β1, Collagen I, and α-SMA expressions in the neonatal epithelial tissues of DM rats. However, the use of Compound C reversed the effects of EGCG. Conclusions: These findings indicated that EGCG restored keratinocyte autophagy to promote diabetic wound healing through the AMPK/ULK1 pathway.

Published in Frontiers in Bioscience-Landmark

ISSN: 2768-6701 (Print); 2768-6698 (Online)
Publisher: IMR Press
Country of publisher: Singapore
LCC subjects: Science: Chemistry: Organic chemistry: Biochemistry; Science: Biology (General)
Website: https://www.imrpress.com/journal/FBL

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