微小RNA（microRNA, miR）作为内源性非编码RNA，参与转录后调控。miR⁃378a在骨骼肌高表达，对肌生成、稳态维持及疾病进程有重要作用。研究表明，miR⁃378a可通过调控组蛋白去乙酰化酶4、丝裂原活化蛋白激酶1等分子，参与成肌分化、能量代谢及肌纤维类型转化等过程。miR⁃378a异常表达与肌肉疾病相关：在杜氏肌营养不良症中，表达水平与病情严重程度呈负相关，过表达可改善表型；在3型肢带型肌营养不良症、横纹肌肉瘤、肌少症及脊髓性肌萎缩症中，其作为潜在生物标志物或治疗靶点的价值已受到关注。该综述总结miR⁃378a的分子特性及其在骨骼肌发育与相关疾病中的作用，为临床转化提供参考。

MicroRNAs (miRNAs) are endogenous noncoding RNAs involved in post-transcriptional regulation. miR-378a is highly expressed in skeletal muscle and plays important roles in myogenesis, maintenance of muscle homeostasis, and disease progression. Studies indicate that miR-378a participates in myogenic differentiation, energy metabolism, and muscle fiber-type switching by regulating molecules such as histone deacetylase 4 and mitogen-activated protein kinase 1. Dysregulated miR-378a is associated with muscle diseases: in Duchenne muscular dystrophy, its expression level negatively correlates with disease severity, and overexpression can ameliorate disease phenotypes; in limb-girdle muscular dystrophy type 3, rhabdomyosarcoma, sarcopenia, and spinal muscular atrophy, its potential value as a biomarker or therapeutic target has attracted increasing attention. This review summarizes the molecular characteristics of miR-378a and its roles in skeletal muscle development and related diseases, providing a reference for clinical translation.