Kelder Bruce, Boyce Keith, Kriete Andres, Clark Ryan, Berryman Darlene E, Nagatomi Sheila, List Edward O, Braughler Mark, Kopchick John J
Edison Biotechnology Institute, Ohio University, Athens, OH 45701, USA.
Comp Hepatol. 2007 May 1;6:4. doi: 10.1186/1476-5926-6-4.
Increased levels of circulating fatty acids caused by insulin resistance and increased adipocyte lipolysis can accumulate within the liver resulting in steatosis. This steatosis sensitizes the liver to inflammation and further injury which can lead to liver dysfunction. We performed microarray analysis on normal mouse liver tissue at different ages and type 2 diabetic liver exhibiting steatosis to identify differentially expressed genes involved in lipid accumulation and liver dysfunction.
Microarray analysis identified CIDE-A as the most differentially expressed gene as a function of age. Mice fed a high fat diet developed hyperinsulinemia, hyperglycemia and liver steatosis, all features of the human metabolic syndrome. Increased CIDE-A expression was observed in type 2 diabetic liver and the elevated CIDE-A expression could be reversed by weight loss and normalization of plasma insulin. Also, CIDE-A expression was found to be correlated with hepatic lipid accumulation.
The corresponding increase in CIDE-A expression with hyperinsulinemia and liver steatosis suggests a novel pathway for lipid accumulation in the liver.
胰岛素抵抗和脂肪细胞脂解增加导致循环脂肪酸水平升高,可在肝脏内蓄积,导致脂肪变性。这种脂肪变性使肝脏对炎症和进一步损伤敏感,进而可导致肝功能障碍。我们对不同年龄的正常小鼠肝脏组织和出现脂肪变性的2型糖尿病肝脏进行了微阵列分析,以鉴定参与脂质蓄积和肝功能障碍的差异表达基因。
微阵列分析确定CIDE-A是随年龄变化差异表达最显著的基因。喂食高脂饮食的小鼠出现高胰岛素血症、高血糖和肝脏脂肪变性,这些都是人类代谢综合征的特征。在2型糖尿病肝脏中观察到CIDE-A表达增加,体重减轻和血浆胰岛素正常化可使升高的CIDE-A表达逆转。此外,发现CIDE-A表达与肝脏脂质蓄积相关。
CIDE-A表达随高胰岛素血症和肝脏脂肪变性相应增加,提示肝脏脂质蓄积的新途径。