Kawaguchi Takumi, Itou Minoru, Taniguchi Eitaro, Sata Michio
Division of Gastroenterology, Department of Medicine, Kurume University School of Medicine, Kurume 830‑0011, Japan.
Int J Mol Med. 2014 Sep;34(3):782-7. doi: 10.3892/ijmm.2014.1826. Epub 2014 Jun 27.
Glucagon‑like peptide‑1 (GLP‑1) is involved in the development of non‑alcoholic steatohepatitis (NASH), which is characterized by fatty acid imbalance. The aim of this study was to investigate the effects of the GLP‑1 receptor (GLP‑1R) agonist, exendin‑4 (Ex‑4), on hepatic fatty acid metabolism and its key enzyme, Δ‑5‑desaturase, in a murine model of NASH. NASH was induced in db/db mice fed a methionine‑choline deficient (MCD) diet. Ex‑4 (n=4) or saline [control (CON); n=4] was administered intraperitoneally for 8 weeks. Steatohepatitis activity was evaluated by non‑alcoholic fatty liver disease (NAFLD) activity score. Hepatic fatty acid composition and Δ‑5‑desaturase index were analyzed by gas chromatography. Ex‑4 treatment significantly reduced body weight and the NAFLD activity score. Hepatic concentrations of long‑chain saturated fatty acids (SFAs) were significantly higher in the Ex‑4 group compared to the CON group (23240±955 vs. 31710±8436 µg/g•liver, P<0.05).Ex‑4 significantly reduced hepatic n‑3 polyunsaturated fatty acid (PUFA)/n‑6 PUFA ratio compared to the CON group (13.83±3.15 vs. 8.73±1.95, P<0.05). In addition, the hepatic Δ‑5‑desaturase index was significantly reduced in the Ex‑4 group compared to the CON group (31.1±12.4 vs. 10.5±3.1, P<0.05). In conclusion, the results showed that Ex‑4 improved steatohepatitis in a murine model of NASH. Furthermore, Ex‑4 altered hepatic long‑chain saturated and PUFA composition and reduced the Δ‑5‑desaturase index. Thus, Ex‑4 may improve NASH by regulating hepatic fatty acid metabolism.
胰高血糖素样肽-1(GLP-1)参与非酒精性脂肪性肝炎(NASH)的发生发展,其特征为脂肪酸失衡。本研究旨在探讨GLP-1受体(GLP-1R)激动剂艾塞那肽-4(Ex-4)对NASH小鼠模型肝脏脂肪酸代谢及其关键酶Δ-5-去饱和酶的影响。通过给db/db小鼠喂食蛋氨酸-胆碱缺乏(MCD)饮食诱导NASH。将Ex-4(n = 4)或生理盐水[对照组(CON);n = 4]腹腔注射8周。通过非酒精性脂肪性肝病(NAFLD)活动评分评估脂肪性肝炎活动度。采用气相色谱法分析肝脏脂肪酸组成和Δ-5-去饱和酶指数。Ex-4治疗显著降低体重和NAFLD活动评分。与CON组相比,Ex-4组肝脏长链饱和脂肪酸(SFA)浓度显著更高(23240±955 vs. 31710±8436 µg/g•肝脏,P<0.05)。与CON组相比,Ex-4显著降低肝脏n-3多不饱和脂肪酸(PUFA)/n-6 PUFA比值(13.83±3.15 vs. 8.73±1.95,P<0.05)。此外,与CON组相比,Ex-4组肝脏Δ-5-去饱和酶指数显著降低(31.1±12.4 vs. 10.5±3.1,P<0.05)。总之,结果表明Ex-4改善了NASH小鼠模型的脂肪性肝炎。此外,Ex-4改变了肝脏长链饱和脂肪酸和PUFA组成,并降低了Δ-5-去饱和酶指数。因此,Ex-4可能通过调节肝脏脂肪酸代谢改善NASH。