miR-885-5p Predicts the Risk and Development of Intracranial Hemorrhage in Traumatic Brain Injury and Regulates Inflammation in Microglia

Abstract

Intracranial hemorrhage (ICH) is the most critical secondary lesion of traumatic brain injury (TBI). Identifying novel biomarkers for the prediction of ICH occurrence and development in TBI patients would benefit the prognosis of TBI and provide targeted nursing strategies for ICH secondary to TBI. The study enrolled a total of 208 TBI patients, where 105 patients had ICH. Serum samples were collected and analyzed with PCR to evaluate the expression of miR-885-5p. The significance of miR-885-5p in predicting the risk and progression of ICH in TBI patients was assessed. Microglia was induced by lipopolysaccharide (LPS) and transfected with miR-885-5p mimic. The inflammation in microglia was estimated by the levels of TNF-α, IL-6, and IL-1β using ELISA. Significant downregulation of miR-885-5p was observed in ICH patients secondary to TBI, which was identified as a risk factor for ICH and discriminated TBI-ICH patients from TBI patients without secondary lesions. Reduced serum miR-885-5p was significantly associated with lower GCS score, lower NIHSS score, increasing intracranial hemorrhage, increasing edema volume of peripheral tissues, and dysregulated coagulation function of ICH patients. In microglia, LPS induced the downregulation of miR-885-5p and increasing levels of TNF-α, IL-6, and IL-1β. The overexpression of miR-885-5p could alleviate LPS-induced inflammation in microglia. Downregulated miR-885-5p predicted the occurrence and severity of ICH secondary to TBI and regulated neuroinflammation in microglia.