Department of Pharmacology, German Institute of Human Nutrition Potsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany.
Diabetologia. 2010 Feb;53(2):309-20. doi: 10.1007/s00125-009-1576-4. Epub 2009 Nov 10.
AIMS/HYPOTHESIS: Numerous new genes have recently been identified in genome-wide association studies for type 2 diabetes. Most are highly expressed in beta cells and presumably play important roles in their function. However, these genes account for only a small proportion of total risk and there are likely to be additional candidate genes not detected by current methodology. We therefore investigated islets from the polygenic New Zealand mouse (NZL) model of diet-induced beta cell dysfunction to identify novel genes and pathways that may play a role in the pathogenesis of diabetes.
NZL mice were fed a diabetogenic high-fat diet (HF) or a diabetes-protective carbohydrate-free HF diet (CHF). Pancreatic islets were isolated by laser capture microdissection (LCM) and subjected to genome-wide transcriptome analyses.
In the prediabetic state, 2,109 islet transcripts were differentially regulated (>1.5-fold) between HF and CHF diets. Of the genes identified, 39 (e.g. Cacna1d, Chd2, Clip2, Igf2bp2, Dach1, Tspan8) correlated with data from the Diabetes Genetics Initiative and Wellcome Trust Case Control Consortium genome-wide scans for type 2 diabetes, thus validating our approach. HF diet induced early changes in gene expression associated with increased cell-cycle progression, proliferation and differentiation of islet cells, and oxidative stress (e.g. Cdkn1b, Tmem27, Pax6, Cat, Prdx4 and Txnip). In addition, pathway analysis identified oxidative phosphorylation as the predominant gene-set that was significantly upregulated in response to the diabetogenic HF diet.
CONCLUSIONS/INTERPRETATION: We demonstrated that LCM of pancreatic islet cells in combination with transcriptional profiling can be successfully used to identify novel candidate genes for diabetes. Our data strongly implicate glucose-induced oxidative stress in disease progression.
目的/假设：最近在 2 型糖尿病的全基因组关联研究中发现了许多新基因。大多数在β细胞中高度表达，推测在其功能中发挥重要作用。然而，这些基因仅占总风险的一小部分，并且可能存在当前方法未检测到的其他候选基因。因此，我们研究了多基因新西兰小鼠（NZL）模型的胰岛，以确定可能在糖尿病发病机制中起作用的新基因和途径。
NZL 小鼠喂食致糖尿病的高脂肪饮食（HF）或糖尿病保护的无碳水化合物 HF 饮食（CHF）。通过激光捕获显微解剖（LCM）分离胰岛，并进行全基因组转录组分析。
在糖尿病前期，HF 和 CHF 饮食之间有 2109 个胰岛转录本差异调节（> 1.5 倍）。鉴定的基因中，39 个（例如 Cacna1d、Chd2、Clip2、Igf2bp2、Dach1、Tspan8）与糖尿病遗传学倡议和威康信托基金会病例对照联盟全基因组扫描 2 型糖尿病的数据相关，从而验证了我们的方法。HF 饮食诱导与胰岛细胞增殖和分化以及氧化应激相关的早期基因表达变化（例如 Cdkn1b、Tmem27、Pax6、Cat、Prdx4 和 Txnip）。此外，通路分析确定氧化磷酸化为对致糖尿病 HF 饮食有显著上调反应的主要基因集。
结论/解释：我们证明了胰腺胰岛细胞的 LCM 与转录谱分析相结合可成功用于鉴定糖尿病的新候选基因。我们的数据强烈表明葡萄糖诱导的氧化应激在疾病进展中起作用。
