Comprehensive analysis of differences of RNA 5-methylcytosine in hepatic lipid metabolism

As living standards have risen, particularly with the widespread consumption of high-fat diets, non-alcoholic fatty liver disease (NAFLD) has emerged as the leading chronic liver condition globally, affecting nearly 30% of adults in China. Recent studies emphasize the role of 5-methylcytosine (m5C), an RNA modification, in key biological functions. Nevertheless, the connection between m5C methylation and NAFLD remains enigmatic. In this research, by leveraging RNA transcriptome sequencing (RNA-Seq) and methylated RNA bisulfite sequencing (Bis-Seq) in leptin receptor-deficient mice, we uncovered that genes associated with hypermethylation were primarily tied to lipid metabolism. Our analysis identified 156 overlapping and differentially expressed genes (DEGs) that showed significant alterations in both m5C modification and mRNA expression levels. Notably, 72 genes showed heightened expression and increased m5C modification, suggesting a positive correlation between m5C RNA modifications and NAFLD. These findings underscore the potential importance of m5C methylation in the progression of NAFLD. Male C57BL/6J and db/db mice aged 8 weeks were purchased from the GemPharmatech ( Shanghai, China). Mice were anesthetized with 10% chloral hydrate.

随着生活水平不断提升，尤其是高脂饮食的广泛流行，非酒精性脂肪性肝病（non-alcoholic fatty liver disease, NAFLD）已成为全球范围内首要的慢性肝脏疾病，在中国影响了近30%的成年人口。近年来的研究凸显了RNA修饰5-甲基胞嘧啶（5-methylcytosine, m5C）在核心生物学功能中的作用。然而，m5C甲基化与非酒精性脂肪性肝病之间的关联仍不明朗。本研究通过对瘦素受体缺陷小鼠（leptin receptor-deficient mice）开展RNA转录组测序（RNA transcriptome sequencing, RNA-Seq）与甲基化RNA亚硫酸氢盐测序（methylated RNA bisulfite sequencing, Bis-Seq），揭示了高甲基化相关基因主要与脂质代谢密切相关。本分析共鉴定出156个重叠差异表达基因（differentially expressed genes, DEGs），该类基因在m5C修饰水平与mRNA表达水平上均发生了显著改变。值得注意的是，其中72个基因的表达水平与m5C修饰水平均呈升高趋势，提示m5C RNA修饰与非酒精性脂肪性肝病之间存在正相关关系。上述研究结果凸显了m5C甲基化在非酒精性脂肪性肝病进展过程中的潜在重要价值。本研究使用的8周龄雄性C57BL/6J小鼠与db/db小鼠均购自中国上海的GemPharmatech公司。小鼠以10%水合氯醛进行麻醉。