Novel Models of Diabetic Nephropathy

糖尿病肾病的新模型

基本信息

批准号：
7682089
负责人：
MOSHE LEVI
金额：
$ 30.81万
依托单位：
UNIVERSITY OF COLORADO DENVER
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-09-30 至 2011-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7682089
关键词：
Advanced Glycosylation End Products Albuminuria Attenuated Binding Proteins Biochemical Blood Pressure Breeding Calmodulin Carbohydrates Cholesterol Crossbreeding Development Diabetic Nephropathy Diabetic mouse Diet Diffuse Enzymes Fibrosis Genetic Glomerular Filtration Rate Growth Factor Inflammation Inflammatory Injury Insulin Insulin Resistance Insulin-Dependent Diabetes Mellitus Kidney Knockout Mice Lipids Mediating Modeling Mus Non-Insulin-Dependent Diabetes Mellitus Obesity Oxidative Stress Pathogenesis Phenotype Play Predisposition Proteinuria Response Elements Role SRE-1 binding protein SRE-2 binding protein Structure of glomerular mesangium Transgenes Transgenic Mice Triglycerides base carbohydrate metabolism cytokine db/db mouse diabetic glomerulosclerosis mouse model novel overexpression podocyte prevent promoter protein expression receptor

项目摘要

DESCRIPTION (provided by applicant): Background: In a) OVE26 mice with type 1 diabetes, b) C57BI/6 mice with diet induced obesity and insulin resistance, and c) db/db mice with type 2 diabetes mellitus, we have found increased renal expression of the transcriptional factors, i) the sterol regulatory element binding proteins 1 and 2 (SREBP-1 and SREBP-2), and ii) the carbohydrate response element binding protein (ChREBP), which result in increased synthesis and accumulation of triglyceride and cholesterol. The lipid accumulation is associated with development of robust glomerulosclerosis, tubulointerstitial fibrosis, and proteinuria. We have also found that the Farnesoid X Receptor (FXR) is highly expressed in the kidney and the expression of FXR and its target enzymes is decreased in the diabetic kidney. Furthermore we have determined that FXR is an important regulator of SREBP-1 and ChREBP expression as well as oxidative stress, advanced glycation end products (AGEs/RAGE), pro-inflammatory cytokines, and fibrosis inducing growth factors. Hypothesis: Based on these finding we propose that FXR plays an important role on the pathogenesis of diabetic nephropathy. We hypothesize that deletion of FXR will markedly enhance and overexpression of FXR will attenuate diabetic nephropathy in mouse models of type 1 (OVE26) and type 2 (db/db) diabetes. Mouse Model 1: A) We will generate FXR knockout mice, currently on the C57BI/6 genetic background, on Background: In a) OVE26 mice with type 1 diabetes, b) C57BI/6 mice with diet induced obesity and insulin the FVB, and if need be and DBA/2J genetic backgrounds, 2 genetic backgrounds that have been documented to have increased susceptibility to diabetic nephropathy. B) We will then cross breed FXR KO mice on FVB background with i) OVE26 mice (type 1 diabetes) on FVB background or ii) db/db mice (type 2 diabetes) on FVB background to determine if FXR deletion accentuates and accelerates diabetic nephropathy. C) We will generate renal podocyte specific FXR knockout mice on FVB background using the Lox-Cre approach (FXRf/f mice crossed with Nphs2 Cre mice). D) We will then crossbreed podocyte FXR KO mice with i) OVE26 mice or ii) db/db mice. Mouse Model 2: A) We will generate renal podocyte specific conditional and inducible FXR transgenic mice in the FVB Background. B) We will then crossbreed the podocyte specific FXR transgenic mice with OVE26 or db/db mice to determine if increased expression of FXR attenuates or prevents diabetic nephropathy. Phenotyping: In these mice we will determine a) the manifestation of diabetic nephropathy, including glomerular filtration rate, glomerulosclerosis, tubulointerstitial fibrosis, and proteinuria and b) the cellular and biochemical mechanisms that mediate diabetic renal injury including lipid and carbohydrate metabolism, inflammation, fibrosis, oxidative stress, and AGEs/RAGE.

描述（由申请人提供）：背景：在 a) 患有 1 型糖尿病的 OVE26 小鼠、b) 患有饮食诱导肥胖和胰岛素抵抗的 C57BI/6 小鼠和 c) 患有 2 型糖尿病的 db/db 小鼠中，我们发现转录因子的肾脏表达增加， i) 甾醇调节元件结合蛋白 1 和 2（SREBP-1 和 SREBP-2），以及 ii) 碳水化合物反应元件结合蛋白 (ChREBP)，这会导致甘油三酯和胆固醇。脂质积累与严重的肾小球硬化、肾小管间质纤维化和蛋白尿的发生有关。我们还发现法尼醇X受体（FXR）在肾脏中高表达，并且FXR及其靶酶在糖尿病肾脏中的表达降低。此外，我们还确定 FXR 是 SREBP-1 和 ChREBP 表达以及氧化应激、晚期糖基化终产物 (AGEs/RAGE)、促炎细胞因子和纤维化诱导生长因子的重要调节因子。假设：基于这些发现，我们提出 FXR 在糖尿病肾病的发病机制中发挥重要作用。我们假设，在 1 型 (OVE26) 和 2 型 (db/db) 糖尿病小鼠模型中，FXR 缺失将显着增强糖尿病肾病，而 FXR 过度表达将减轻糖尿病肾病。小鼠模型 1：A) 我们将生成 FXR 敲除小鼠，目前具有 C57BI/6 遗传背景，背景：a) 患有 1 型糖尿病的 OVE26 小鼠，b) 患有饮食诱导肥胖和胰岛素 FVB 的 C57BI/6 小鼠，如果需要的话，还有 DBA/2J 遗传背景，2 种已被证明对糖尿病肾病易感性增加的遗传背景。 B) 然后，我们将 FVB 背景的 FXR KO 小鼠与 i) FVB 背景的 OVE26 小鼠（1 型糖尿病）或 ii) FVB 背景的 db/db 小鼠（2 型糖尿病）杂交，以确定 FXR 缺失是否会加剧和加速糖尿病肾病。 C) 我们将使用 Lox-Cre 方法在 FVB 背景上生成肾足细胞特异性 FXR 敲除小鼠（FXRf/f 小鼠与 Nphs2 Cre 小鼠杂交）。 D) 然后我们将足细胞 FXR KO 小鼠与 i) OVE26 小鼠或 ii) db/db 小鼠杂交。小鼠模型 2：A) 我们将在 FVB 背景中生成肾足细胞特异性条件性和可诱导的 FXR 转基因小鼠。 B) 然后，我们将足细胞特异性 FXR 转基因小鼠与 OVE26 或 db/db 小鼠杂交，以确定 FXR 表达的增加是否会减轻或预防糖尿病肾病。表型分析：在这些小鼠中，我们将确定 a) 糖尿病肾病的表现，包括肾小球滤过率、肾小球硬化、肾小管间质纤维化和蛋白尿，以及 b) 介导糖尿病肾损伤的细胞和生化机制，包括脂质和碳水化合物代谢、炎症、纤维化、氧化应激和 AGE/RAGE。