Mechanisms and Research Progress of Leech in Diabetic Ulcer Fibrosis.

Delayed wound healing is a major complication of diabetes, with its core pathological process being pathological fibrosis driven by persistent inflammation, metabolic disorders and vascular dysfunction under hyperglycemia. This process involves pathological retention of inflammatory cells, abnormal expression of pro-fibrotic factors, and excessive deposition of extracellular matrix. As a traditional Chinese medicine, leech possesses multiple pharmacological effects including anticoagulation, anti-inflammation and improvement of microcirculation, exerting its therapeutic roles through regulating coagulation, modulating inflammatory responses, and enhancing vascular microcirculation. Simultaneously, leech can reduce epithelial-mesenchymal transition and extracellular matrix deposition by synergistically inhibiting multiple key signalling pathways associated with fibrosis. Future research should focus on elucidating the bioactive components of leech and their synergistic regulatory networks across multiple signalling pathways, providing a theoretical reference for developing leech-based anti-fibrotic drugs.