Decreased Expression of Plasma MicroRNA in Patients with Methamphetamine (MA) Use Disorder.

Recent research have revealed that circulating miRNAs may offer noninvasive biomarkers for human disease, offering the prospect for earlier diagnosis, and improved precision of diagnoses. The diagnoses of drug use disorders is still mainly based on subjective report and no objective biomarkers available. Many animal and cell studies found that miRNAs were involved in substance use disorders, including alcohol, morphine, cocaine and amphetamine use disorders. However, no study on circulating miRNAs for drug use disorders so far. We investigated the differential expression of plasma miRNAs in 124 patients with methamphetamine (MA) use disorders. Based on the preliminary results from microarray screen, plasma expression of 6 candidate miRNAs were measured by Quantitative real-time RT-PCR. We found that the expression of miR181a, miR15b, miR- let-7e, miR- let-7d in plasma were decreased compared to normal controls. The expression of the altered miRNAs were negative correlated with drug use frequencies in past months. Our findings suggested that miR-181a, miR-15b, miR-let-7e and miR-let-7d may play a potential role in the pathology of MA use disorder, and could serve as a potential peripheral biomarker for MA use disorder when confirmed by future studies. Further study are needed to elucidate the molecular mechanism modulated by miRNAs and explore potential novel intervention targets.