MicroRNA-21-Mediated Inhibition of Mast Cell Degranulation Involved in the Protective Effect of Berberine on 2,4-Dinitrofluorobenzene-Induced Allergic Contact Dermatitis in Rats via p38 Pathway

AbstractThe study aimed to investigate the effect of berberine on allergic contact dermatitis (ACD) in rats and explore its underlying mechanisms. Firstly, ACD model was established by sensitizing and challenging with 2,4-dinitrofluorobenzene (DNFB) topically, and the rats were treated with berberine. Ear swelling was assessed, and cytokine, IgE, and histamine productions were measured. The ear biopsies were obtained for histology analysis. Additionally, rat peritoneal mast cells (RPMCs) were isolated for detection of microRNA-21 (miR-21) expression, mitogen-activated protein kinase (MAPK) signaling, and MC degranulation. Lastly, RPMCs were transfected with miR-21 mimic or miR-21 inhibitor to investigate the relationship between miR-21 and p38 pathway in MC. Our results showed that berberine significantly attenuated ear swelling in DNFB-induced ACD (ACDvs high dose of berberine 0.48  ± 0.03vs. 0.33  ± 0.03 mm,P <  0.01), inhibited inflammatory cell infiltration (86 ± 5.16vs. 58  ± 4.32 cells/mm2,P <  0.01), reduced MC recruitment (61 ± 4.07vs. 39  ± 3.42 mast cells/mm2,P <  0.01), as well as decreased inflammatory cytokine, IgE, and histamine productions (allP <  0.05). Berberine treatment inhibited miR-21 expression, suppressed β-hexosaminidase and histamine release, and prevented p38 phosphorylation (allP <  0.05), which was abrogated by pretreatment with miR-21 overexpression. These findings indicate that miR-21...
Source: Inflammation - Category: Allergy & Immunology Source Type: research