Methamphetamine-induced alterations in intestinal mucosal barrier function occur via the microRNA-181c/TNF-α/tight junction axis

An enterogenic infection occurs when intestinal mucosal disruption is followed by the invasion of intestinal bacteria into the blood and distant organs, which can result in severe diseases or even death. Our previous study using Rhesus monkeys as an in vivo model revealed that methamphetamine (MA) induced intestinal mucosal barrier damage, which poses a high risk of enterogenic infection. However, how methamphetamine causes intestinal mucosal barrier damage remains largely unknown. In this study, we employed an in vitro model, and found that MA treatment could inhibit the expression of miR-181c, which directly targets and regulates TNF-alpha, and ultimately induces apoptosis and damages the intestinal barrier. Moreover, we measured TNF-alpha serum levels as well as the intestinal mucosal barrier damage indicators (diamine oxidase, D-lactic acid, and exotoxin) and found that their levels were significantly higher in MA-dependents than in healthy controls (P < 0.001). To the best of our knowledge, this is the first report evidencing that miR-181c is involved in MA-induced intestinal barrier injury via TNF-alpha regulation, which introduces novel potential therapeutic targets for MA-dependent intestinal diseases.