Accelerated Wound Healing in Diabetic Rat by miRNA-185-5p and Its Anti-Inflammatory Activity

Abstract

Aim Addressing both inflammation and epithelialization during the treatment of diabetic foot ulcers is an important step, but current treatment options are limited. MiRNA has important prospects in the treatment of diabetic foot refractory wound ulcers. Previous studies have reported that miR-185-5p reduces hepatic glycogen production and fasting blood glucose levels. We herein hypothesized that miR-185-5p might play an important role in the field of diabetic foot wounds. Materials and Methods MiR-185-5p in skin tissue samples from patients with diabetic ulcers and diabetic rats were measured using quantitative real-time PCR (qRT-PCR). The streptozotocin-induced diabetes rat model (male Sprague-Dawley rats) for diabetic wound healing was conducted. The therapeutic potential was observed by subcutaneous injection of miR-185-5p mimic into diabetic rat wounds. The anti-inflammation roles of miR-185-5p on human dermal fibroblast cells were analyzed. Results We found that miR-185-5p is significantly downregulated in diabetic skin (people with DFU and diabetic rats) compared to controls. Further, in vitro upregulation of miR-185-5p decreased the inflammatory factors (IL-6, TNF-α) and intercellular adhesion molecule 1 (ICAM-1) of human skin fibroblasts under advanced glycation end products (AGEs). Meanwhile, the increase of miR-185-5p promoted cell migration. Our results also confirmed that the topical increase of miR-185-5p decreases diabetic wound p-nuclear factor-κB (p-NF-κB), ICAM-1, IL-6, TNF-α, and CD68 expression in diabetic wounds. MiR-185-5p overexpression boosted re-epithelization and expedited wound closure of diabetic rats. Conclusion MiR-185-5p accelerated wound healing of diabetic rats, reepithelization, and inhibited the inflammation of diabetic wounds in the healing process, a potentially new and valid treatment for refractory diabetic foot ulcers.

Immunomodulation in diabetic wounds healing: The intersection of macrophage reprogramming and immunotherapeutic hydrogels

“…Restoration of these specific miRNAs has demonstrated effective mitigation of wound inflammation, acceleration of wound healing, and promotion of epithelialization. 86 , 87 Furthermore, myofibroblasts secrete exosomes enriched with miR-224 and transfer them to macrophages within an inflammatory milieu, thereby inhibiting M2 polarization, while the M1 secretome further stimulates myofibroblast proliferation and induces an exacerbated inflammatory response. 88 Alternatively, stem cells involved in wound repair also modulate macrophage polarization by releasing exosomes enriched with specific miRNAs.…”