Plasma microRNA (miR)-9 has been identified as a promising diagnostic biomarker for traumatic brain injury (TBI). This study aims to investigate the possible role and mechanisms of miR-9a-5p affecting TBI. Microarray-based gene expression profiling of TBI was used for screening differentially expressed miRNAs and genes. TBI rat models were established. miR-9a-5p, ELAVL1 and VEGF expression in the brain tissue of TBI rats was detected. The relationship among miR-9a-5p, ELAVL1 and VEGF was tested. TBI modeled rats were injected with miR-9a-5p-, ELAVL1 or VEGF-related sequences to identify their effects on TBI. miR-9a-5p was poorly expressed in the brain tissue of rats with TBI. ELAVL1 was a downstream target gene of miR-9a-5p, which could negatively regulate its expression. Enforced miR-9a-5p expression prevented brain tissue damage in TBI rats by targeting ELAVL1. Meanwhile, ELAVL1 could increase the expression of VEGF, which was highly expressed in the brain tissue of rats with TBI. In addition, ectopically expressed miR-9a-5p alleviated brain tissue damage in TBI rats by downregulating the ELAVL1/VEGF axis. Overall, miR-9a-5p can potentially reduce brain tissue damage in TBI rats by targeting ELAVL1 and down-regulating VEGF expression.

中文翻译：

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microRNA-9a-5p 破坏 ELAVL1/VEGF 轴以减轻创伤性脑损伤

血浆 microRNA (miR)-9 已被确定为一种有前途的创伤性脑损伤 (TBI) 诊断生物标志物。本研究旨在探讨miR-9a-5p影响TBI的可能作用和机制。基于微阵列的 TBI 基因表达谱用于筛选差异表达的 miRNA 和基因。建立TBI大鼠模型。检测TBI大鼠脑组织中miR-9a-5p、ELAVL1、VEGF的表达量。测试miR-9a-5p、ELAVL1和VEGF之间的关系。 TBI 模型大鼠被注射 miR-9a-5p-、ELAVL1 或 VEGF 相关序列，以鉴定它们对 TBI 的影响。 miR-9a-5p 在 TBI 大鼠的脑组织中表达较差。 ELAVL1是miR-9a-5p的下游靶基因，可以负调控其表达。通过靶向 ELAVL1，强制表达 miR-9a-5p 可预防 TBI 大鼠的脑组织损伤。同时，ELAVL1可以增加VEGF的表达，VEGF在TBI大鼠的脑组织中高表达。此外，异位表达的 miR-9a-5p 通过下调 ELAVL1/VEGF 轴来减轻 TBI 大鼠的脑组织损伤。总体而言，miR-9a-5p 可以通过靶向 ELAVL1 和下调 VEGF 表达来减少 TBI 大鼠的脑组织损伤。