Low molecular weight heparin inhibits circulating fibrocytes differentiation by modulating neuronal nitric oxide synthase and TGF-β1/Smad pathway

AT2R Activation Improves Wound Healing in a Preclinical Mouse Model

Abnormal skin healing resulting in chronic wounds or hypertrophic scarring remains a major healthcare burden. Here, the antifibrotic angiotensin II type 2 receptor (AT2R) signaling pathway was modulated to determine its impact on cutaneous wound healing. Balb/c mice received two splinted full-thickness wounds. Topical treatments with the selective AT2R agonist compound 21 (C21) and/or selective antagonist PD123319 or saline vehicle were administered until sacrifice on post-wounding days 7 or 10. The rate of wound re-epithelialization was accelerated by PD123319 and combination treatments. In vitro, C21 significantly reduced human fibroblast migration. C21 increased both collagen and vascular densities at days 7 and 10 post-wounding and collagen I:III ratio at day 10, while PD123319 and combination treatments decreased them. Genes associated with regeneration and repair were upregulated by C21, while PD123319 treatment increased the expression of genes associated with inflammation and immune cell chemotaxis. C21 treatment reduced wound total leukocyte and neutrophil staining densities, while PD123319 increased these and macrophage densities. Overall, AT2R activation with C21 yields wounds that mature more quickly with structural, cellular, and gene expression profiles more closely approximating unwounded skin. These findings support AT2R signal modulation as a potential therapeutic target to improve skin quality during wound healing.

Adipose-derived stem/stromal cells with heparin-enhanced anti-inflammatory and antifibrotic effects mitigate induced pulmonary fibrosis in mice

Interstitial lung disease (ILD) is a life-threatening pathological condition that causes respiratory failure and often presents as pulmonary fibrosis. Although it is treated using immunosuppressive and antifibrotic agents, the beneficial effects of these agents remain limited. Thus, the development of new therapeutic strategies for lung fibrosis is crucial. Mesenchymal stem/stromal cells (MSCs) have multilineage differentiation potential; additionally, they have anti-inflammatory and antifibrotic effects as well as the ability to modulate the immune response and modify the microenvironment at the site of engraftment. Numerous adipose-derived MSCs (ASCs) are present in the adipose tissue. Heparin and low-molecular-weight heparin (LMWH) mediate the secretion of several cytokines and growth factors with cell migratory and antifibrotic effects. This study aimed to confirm the therapeutic effect of LMWH-activated ASCs on ILD. Mouse ASCs (mASCs) were cultured in an LMWH-supplemented medium. LMWH significantly increased the number of mASC and enhanced their migratory, anti-inflammatory, and antifibrotic effects. Furthermore, mice with bleomycin-induced pulmonary fibrosis were intravenously administered LMWH-activated mASCs. The relative mRNA expression of inflammation-related genes in ILD lungs was significantly lower in the treatment group than in the pathological model group. Our findings suggest that LMWH-activated mASC administration reduces lung fibrosis.