Metabolism Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA.
Harvard Chan Bioinformatics Core, Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA.
JCI Insight. 2020 Aug 20;5(16):140134. doi: 10.1172/jci.insight.140134.
Nonalcoholic fatty liver disease (NAFLD) is a common comorbidity among people living with HIV that has a more aggressive course than NAFLD among the general population. In a recent randomized placebo-controlled trial, we demonstrated that the growth hormone-releasing hormone analog tesamorelin reduced liver fat and prevented fibrosis progression in HIV-associated NAFLD over 1 year. As such, tesamorelin is the first strategy that has shown to be effective against NAFLD among the population with HIV. The current study leveraged paired liver biopsy specimens from this trial to identify hepatic gene pathways that are differentially modulated by tesamorelin versus placebo. Using gene set enrichment analysis, we found that tesamorelin increased hepatic expression of hallmark gene sets involved in oxidative phosphorylation and decreased hepatic expression of gene sets contributing to inflammation, tissue repair, and cell division. Tesamorelin also reciprocally up- and downregulated curated gene sets associated with favorable and poor hepatocellular carcinoma prognosis, respectively. Notably, among tesamorelin-treated participants, these changes in hepatic expression correlated with improved fibrosis-related gene score. Our findings inform our knowledge of the biology of pulsatile growth hormone action and provide a mechanistic basis for the observed clinical effects of tesamorelin on the liver.
非酒精性脂肪性肝病 (NAFLD) 是 HIV 感染者常见的合并症,其病程比普通人群中的 NAFLD 更为侵袭。在最近一项随机安慰剂对照试验中,我们证明了生长激素释放激素类似物特立莫林可在 1 年内减少 HIV 相关性 NAFLD 的肝脂肪并防止纤维化进展。因此,特立莫林是针对 HIV 人群中 NAFLD 显示有效的第一种策略。本研究利用该试验的配对肝活检标本,鉴定了特立莫林与安慰剂相比差异调节的肝基因途径。使用基因集富集分析,我们发现特立莫林增加了与氧化磷酸化相关的标志性基因集在肝脏中的表达,并降低了与炎症、组织修复和细胞分裂相关的基因集在肝脏中的表达。特立莫林还分别上调和下调了与肝细胞癌预后良好和不良相关的经过精心整理的基因集。值得注意的是,在接受特立莫林治疗的参与者中,这些肝表达的变化与改善的纤维化相关基因评分相关。我们的研究结果丰富了我们对脉冲生长激素作用生物学的认识,并为观察到的特立莫林对肝脏的临床效果提供了机制基础。