Exosomal miR-19b-3p communicates tubular epithelial cells and M1 macrophage

Accumulating evidence has demonstrated that microRNAs (miRNAs), one type of noncoding RNAs, often have short nucleotides (18–25) in length, and negatively regulate gene expression in post-transcriptional level through inhibition of mRNAs or cleavage of mRNAs. Clearly, miRNAs exert their various activities due to the fact that their downstream targets have different biological functions. Recently, miR-19b-3p has been characterized to play a crucial role via different molecular mechanisms in various diseases (Fig. 1 ). For example, miR-19b-3p is identified to modulate Japanese encephalitis virus (JEV)-mediated inflammation through repression of ring finger protein 11 (RNF11), indicating that miR-19b-3p could be useful for treating viral encephalitis 1 . One study dissected that miR-19b-3p is significantly decreased in exosomes derived from cerebrospinal fluid in the patients with Parkinson’s disease (PD) 2 . However, another study elucidated that plasma miR-19b-3p level is higher in the PD patients compared with healthy persons and multiple-system atrophy (MSA) patients, indicating that miR-19b-3p could be involved in pathophysiology or symptoms of PD and MSA 3 . Notably, miR-19b-3p is reported to be a potential candidate for prediction of autism spectrum disorder (ASD) 4 . Interestingly, miR-19b-3p was reported to play a pivotal role in coordinated guidance of osteoblastic differentiation. Strikingly, miR-19b-3p governs osteogenic differentiation in muscle cells with PDGFRα expression via targeting phosphate and tension homology deleted on chromosome ten (PTEN) 5 . One group revealed that circulating miR-19b-3p could be a potent biomarker for diffuse myocardial fibrosis in hypertrophic cardiomyopathy 6 . In line with this, circulating miR-19b-3p level is correlated to the myocardium level in diabetic cardiomyopathy development, suggesting that this miRNA might be a suitable biomarker in asymptomatic diabetic patients for detection of cardiac dysfunction 7 . Interestingly, miR-19b-3p is involved in liver fibrosis via inhibition of C–C motif chemokine receptor (CCR2). Moreover, miR-19b-3p is dissected to play a potential role in ovarian response to gonadotropins 8 . Low serum expression of miR-19b-3p is observed, and associates with a phenotype of structuring Crohn’s disease 9 . These reports delineate that miR-19b-3p critically participated in the development of human diseases. Fig. 1: Molecular mechanism of miR-19b-3p is illustrated in cellular functions. MiR-19b-3p has been characterized to play a critical role in multiple human diseases via inhibition of its multiple targets that are involved in cell proliferation, drug resistance, EMT, metastasis, inflammation, and radiosensitivity Full size image