Department of Clinical Biochemistry, Chinese People's Liberation Army General Hospital, 28 Fu-Xing Road, Beijing, China.
Lipids Health Dis. 2010 Jul 26;9:78. doi: 10.1186/1476-511X-9-78.
Non-alcoholic fatty liver disease (NAFLD), which is characterized by hepatic steatosis, can be reversed by early treatment. Several case reports have indicated that the administration of recombinant growth hormone (GH) could improve fatty liver in GH-deficient patients. Here, we investigated whether chronic exogenous GH levels could improve hepatic steatosis induced by a high-fat diet in rats, and explored the underlying mechanisms.
High-fat diet-fed rats developed abdominal obesity, fatty liver and insulin resistance. Chronic exogenous GH improved fatty liver, by reversing dyslipidaemia, fat accumulation and insulin resistance. Exogenous GH also reduced serum tumour necrosis factor-alpha (TNF-alpha) levels, and ameliorated hepatic lipid peroxidation and oxidative stress. Hepatic fat deposition was also reduced by exogenous GH levels, as was the expression of adipocyte-derived adipokines (adiponectin, leptin and resistin), which might improve lipid metabolism and hepatic steatosis. Exogenous GH seems to improve fatty liver by reducing fat weight, improving insulin sensitivity and correcting oxidative stress, which may be achieved through phosphorylation or dephosphorylation of a group of signal transducers and activators of hepatic signal transduction pathways.
Chronic exogenous GH has positive effects on fatty liver and may be a potential clinical application in the prevention or reversal of fatty liver. However, chronic secretion of exogenous GH, even at a low level, may increase serum glucose and insulin levels in rats fed a standard diet, and thus increase the risk of insulin resistance.
非酒精性脂肪性肝病（NAFLD）的特征为肝脂肪变性，早期治疗可逆转。一些病例报告表明，重组生长激素（GH）的给药可以改善 GH 缺乏症患者的脂肪肝。在这里，我们研究了慢性外源性 GH 水平是否可以改善高脂肪饮食诱导的大鼠肝脂肪变性，并探讨了潜在的机制。
高脂肪饮食喂养的大鼠出现腹部肥胖、脂肪肝和胰岛素抵抗。慢性外源性 GH 通过逆转血脂异常、脂肪堆积和胰岛素抵抗改善了脂肪肝。外源性 GH 还降低了血清肿瘤坏死因子-α（TNF-α）水平，并改善了肝脂质过氧化和氧化应激。外源性 GH 还降低了肝脂肪沉积，以及脂肪细胞衍生的脂肪因子（脂联素、瘦素和抵抗素）的表达，这可能改善了脂质代谢和肝脂肪变性。外源性 GH 通过减少脂肪重量、改善胰岛素敏感性和纠正氧化应激来改善脂肪肝，这可能是通过磷酸化或去磷酸化一组肝信号转导途径的信号转导物和激活物来实现的。
慢性外源性 GH 对脂肪肝有积极作用，可能是预防或逆转脂肪肝的潜在临床应用。然而，即使在低水平下，慢性分泌外源性 GH 也会增加标准饮食喂养大鼠的血清葡萄糖和胰岛素水平，从而增加胰岛素抵抗的风险。
