Department of Drug Safety Sciences Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan.
Toxicol Sci. 2018 Nov 1;166(1):228-239. doi: 10.1093/toxsci/kfy200.
Recently, studies on circulating microRNAs (miRNAs) as potential biomarkers of drug-induced liver injury (DILI) have received increasing attention. It has been demonstrated that miR-122 and miR-192, which are liver enriched, could be potential biomarkers of DILI; however, these miRNAs cannot discern types of injuries. In the present study, we comprehensively analyzed time-dependent plasma miRNA profiles in rats with drug- or chemical-induced hepatocellular injury, cholestasis, and steatosis with high-throughput miRNA sequencing. To enable the comparison of miRNA expression levels between DILI models with different severity and peak time of injuries, the stages of injury were defined as early, middle, and late, according to cluster patterns of miRNA expression profiles. Through differential analysis, we characterized miRNAs that were specifically up- or down-regulated in each DILI model. Several miRNAs were dramatically changed earlier than traditional biomarkers such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST). For example, in an acetaminophen (APAP)-induced hepatocellular injury model, plasma let-7b-5p was up-regulated as early as 3 h after dosing, whereas a significant change in ALT level was observed at 12 h. We then focused on the DILI type-specific miRNAs in plasma that were up-regulated at the early stage of injury. RT-qPCR analysis validated that let-7b-5p and miR-1-3p for hepatocellular injury, miR-143-3p and miR-218a-5p for cholestasis, and miR-320-3p for steatosis models showed significant increases in the early stage of the injuries. The present study suggests the utility of miRNAs as specific biomarkers for the early detection of DILI.
最近，人们对循环 microRNAs（miRNAs）作为药物性肝损伤（DILI）潜在生物标志物的研究越来越关注。研究表明，肝脏特异性富集的 miR-122 和 miR-192 可能是 DILI 的潜在生物标志物，但这些 miRNA 无法区分损伤类型。在本研究中，我们通过高通量 miRNA 测序，全面分析了药物或化学诱导的肝细胞损伤、胆汁淤积和脂肪变性大鼠的血浆 miRNA 谱。为了能够比较不同严重程度和损伤峰值时间的 DILI 模型之间的 miRNA 表达水平，根据 miRNA 表达谱的聚类模式，将损伤阶段定义为早期、中期和晚期。通过差异分析，我们鉴定了每个 DILI 模型中特异性上调或下调的 miRNA。与丙氨酸氨基转移酶（ALT）和天冬氨酸氨基转移酶（AST）等传统生物标志物相比，一些 miRNA 的变化出现得更早。例如，在乙酰氨基酚（APAP）诱导的肝细胞损伤模型中，血浆 let-7b-5p 在给药后 3 小时即被上调，而 ALT 水平的显著变化则发生在 12 小时。然后，我们关注了在损伤早期上调的 DILI 型特异性血浆 miRNA。实时 qPCR 分析验证了 let-7b-5p 和 miR-1-3p 用于肝细胞损伤，miR-143-3p 和 miR-218a-5p 用于胆汁淤积，miR-320-3p 用于脂肪变性模型，在损伤的早期阶段均有明显增加。本研究表明，miRNA 可作为 DILI 早期检测的特异性生物标志物。
