Department of Gastroenterology, Graduate School of Medicine, Kanazawa University, Kanazawa, Japan.
Liver Int. 2015 Feb;35(2):582-90. doi: 10.1111/liv.12685. Epub 2014 Oct 10.
BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) is closely related to insulin resistance and lipid metabolism. Recent studies have suggested that the quality of fat accumulated in the liver is associated with the development of nonalcoholic steatohepatitis (NASH). In this study, we investigated the fatty acid composition in liver tissue and its association with the pathology in NAFLD patients.
One hundred and three patients diagnosed with NAFLD [simple steatosis (SS): 63, NASH: 40] were examined and their hepatic fatty acids were measured using gas chromatography. In addition, relationships between the composition and composition ratios of various fatty acids and patient backgrounds, laboratory test values, histology of the liver, and expression of fat metabolism-related enzymes were investigated.
The C16:1n7 content, the C16:1n7/C16:0 and C18:1n9/C18:0 ratios were increased and the C18:0/C16:0 ratio was decreased in the NASH group. The C18:0/C16:0 and C18:1n9/C18:0 ratios were associated with the steatosis score in liver tissue, and the C16:1n7/C16:0 ratio was associated with the lobular inflammation score. The expressions levels of genes: SCD1, ELOVL6, SREBP1c, FAS and PPARγ were enhanced in the NASH group. In multivariate analysis, the C18:0/C16:0 ratio was the most important factor that was correlated with the steatosis score. In contrast, the C16:1n7/C16:0 ratio was correlated with lobular inflammation.
The fatty acid composition in liver tissue and expression of genes related to fatty acid metabolism were different between the SS and NASH groups, suggesting that the acceleration of fatty acid metabolism is deeply involved in pathogenesis of NASH.
非酒精性脂肪性肝病（NAFLD）与胰岛素抵抗和脂质代谢密切相关。最近的研究表明，肝脏中积累的脂肪的质量与非酒精性脂肪性肝炎（NASH）的发展有关。在本研究中，我们研究了肝组织中的脂肪酸组成及其与 NAFLD 患者病理的关系。
检查了 103 名诊断为 NAFLD 的患者[单纯性脂肪变性（SS）：63 例，NASH：40 例]，并使用气相色谱法测量了他们的肝脂肪酸。此外，还研究了各种脂肪酸的组成及其组成比与患者背景、实验室检查值、肝组织学和脂肪代谢相关酶的表达之间的关系。
NASH 组的 C16:1n7 含量、C16:1n7/C16:0 和 C18:1n9/C18:0 比值增加，C18:0/C16:0 比值降低。C18:0/C16:0 和 C18:1n9/C18:0 比值与肝组织脂肪变性评分相关，C16:1n7/C16:0 比值与小叶炎症评分相关。NASH 组中 SCD1、ELOVL6、SREBP1c、FAS 和 PPARγ 基因的表达水平增强。在多变量分析中，C18:0/C16:0 比值是与脂肪变性评分最相关的最重要因素。相比之下，C16:1n7/C16:0 比值与小叶炎症相关。
SS 和 NASH 组肝组织脂肪酸组成和与脂肪酸代谢相关基因的表达不同，提示脂肪酸代谢的加速与 NASH 的发病机制密切相关。
