Cell Biochem Biophys. 2014 Jan;68(1):25-35. doi: 10.1007/s12013-013-9679-4.
Diabetic cardiomyopathy is a leading cause of morbidity and mortality, and Insulin2 mutant (Ins2+/-) Akita is a genetic mice model of diabetes relevant to humans. Dicer, miRNAs, and inflammatory cytokines are associated with heart failure. However, the differential expression of miRNAs, dicer, and inflammatory molecules are not clear in diabetic cardiomyopathy of Akita. We measured the levels of miRNAs, dicer, pro-inflammatory tumor necrosis factor alpha (TNFα), and anti-inflammatory interleukin 10 (IL-10) in C57BL/6J (WT) and Akita hearts. The results revealed increased heart to body weight ratio and robust expression of brain natriuretic peptide (BNP: a hypertrophy marker) suggesting cardiac hypertrophy in Akita. The multiplex RT-PCR, qPCR, and immunoblotting showed up regulation of dicer, whereas miRNA array elicited spread down regulation of miRNAs in Akita including dramatic down regulation of let-7a, miR-130, miR-142-3p, miR-148, miR-338, miR-345-3p, miR-384-3p, miR-433, miR-450, miR-451, miR-455, miR-494, miR-499, miR-500, miR-542-3p, miR-744, and miR-872. Conversely, miR-295 is induced in Akita. Cardiac TNFα is upregulated at mRNA (RT-PCR and qPCR), protein (immunoblotting), and cellular (immunohistochemistry and confocal microscopy) levels, and is robust in hypertrophic cardiomyocytes suggesting direct association of TNFα with hypertrophy. Contrary to TNFα, cardiac IL-10 is downregulated in Akita. In conclusion, induction of dicer and TNFα, and attenuation of IL-10 and majority of miRNA are associated with cardiomyopathy in Akita and could be used for putative therapeutic target for heart failure in diabetics.
糖尿病性心肌病是发病率和死亡率的主要原因，胰岛素 2 突变（Ins2+/-）Akita 是一种与人相关的糖尿病相关的遗传小鼠模型。Dicer、miRNAs 和炎性细胞因子与心力衰竭有关。然而，在 Akita 的糖尿病性心肌病中，miRNAs、Dicer 和炎性分子的差异表达尚不清楚。我们测量了 C57BL/6J（WT）和 Akita 心脏中的 miRNAs、Dicer、促炎肿瘤坏死因子-α（TNFα）和抗炎白细胞介素 10（IL-10）的水平。结果表明，心脏与体重比增加，脑钠肽（BNP：肥大标志物）的表达强劲，提示 Akita 存在心肌肥大。多重 RT-PCR、qPCR 和免疫印迹显示 Dicer 上调，而 miRNA 阵列显示 Akita 中的 miRNAs 广泛下调，包括 let-7a、miR-130、miR-142-3p、miR-148、miR-338、miR-345-3p、miR-384-3p、miR-433、miR-450、miR-451、miR-455、miR-494、miR-499、miR-500、miR-542-3p、miR-744 和 miR-872 的显著下调。相反，miR-295 在 Akita 中被诱导。心脏 TNFα 在 mRNA（RT-PCR 和 qPCR）、蛋白（免疫印迹）和细胞（免疫组织化学和共聚焦显微镜）水平上调，在肥大心肌细胞中非常强烈，表明 TNFα 与肥大直接相关。与 TNFα 相反，心脏 IL-10 在 Akita 中下调。总之，Dicer 和 TNFα 的诱导，以及 IL-10 和大多数 miRNA 的衰减与 Akita 的心肌病有关，可用于糖尿病患者心力衰竭的潜在治疗靶点。
