Our results shown that miR-26a, miR-133, and miR-221 were upregulated in ASM from horses with asthma exacerbation compared with asthma remission and controls.
We verified that chemokine (C-X-C motif) ligand (CXCL) 17, an anti-inflammatory chemokine, is a target of miR-221-3p, and epithelial CXCL17 expression significantly increased in asthma.
FCS + TGF-β inhibited p21(WAF1) and p27(kip1) expression, and increased microRNA-221 (miR-221) expression in ASMCs from individuals with severe asthma. miR-221, and not miR-222, mimics the increased proliferation and IL-6 release induced by FCS + TGF in healthy ASM, whereas in patients with severe asthma, the inhibition of miR-221, but not miR-222, inhibited proliferation and IL-6 release. miR-221 inhibition led to the increased expression of FCS + TGF-β-induced p21(WAF1) and p27(kip1).