PHARMACOLOGICAL RESCUE OF MUTANT LAMININ IN NEPHROTIC SYNDROME

突变层粘连蛋白对肾病综合征的药理学拯救

基本信息

批准号：
9110975
负责人：
Ying Maggie Chen
金额：
$ 7.63万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-08-01 至 2018-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9110975
关键词：
Accounting Animal Model Apoptosis Apoptotic Attenuated Biological Assay Cells Chemicals Combined Modality Therapy Complex DNA Sequence Alteration Data Destinations Development End stage renal failure Endoplasmic Reticulum Functional disorder Genes Genetic Goals Health Human Hypoalbuminemia In Vitro Individual Injury Kidney Diseases Kidney Failure Knock-out Laminin Lead MG132 Mediating Missense Mutation Molecular Chaperones Morbidity - disease rate Mus Mutant Strains Mice Mutate Mutation Nephrotic Syndrome Pathway interactions Patients Pharmaceutical Preparations Pharmacologic Substance Preclinical Testing Proteasome Inhibitor Protein Conformation Proteins Proteinuria Rattus Renal function Research Risk Signal Transduction System Taurodeoxycholate Therapeutic Therapeutic Intervention Therapeutic Uses Time Transgenic Mice Ubiquitin Western Blotting Wild Type Mouse attenuation base biological adaptation to stress cost effective therapy endoplasmic reticulum stress glomerular basement membrane improved in vivo innovation lamin B2 loss of function mortality mouse model multicatalytic endopeptidase complex mutant nephrin novel strategies novel therapeutics podocyte promoter protein degradation protein misfolding small molecule trafficking treatment effect treatment strategy

项目摘要

DESCRIPTION (provided by applicant): Nephrotic syndrome (NS) is characterized by heavy proteinuria, hypoalbuminemia, and increased risk of progressive loss of kidney function. It causes serious morbidity and high mortality, accounting for 15% of prevalent end-stage renal disease at an annual cost of more than $3 billion in the US. There is no effective treatment for most cases of NS associated with genetic mutations. Our research has been focused on a monogenic form of NS caused by missense mutations of LAMB2, one of the most commonly mutated genes in NS. Laminin ß2 encoded by LAMB2 is a component of laminin-521 (α5ß2γ1), the major laminin trimer of the glomerular basement membrane (GBM). Using our established cell and knockout/transgenic mouse models, we have found that inhibited secretion of misfolded C321R-LAMB2 from podocytes to the GBM and the resulting podocyte endoplasmic reticulum (ER) stress lead to proteinuria. In addition, increased accumulation of the mutant in the GBM alleviates proteinuria. Therefore, restoring defective trafficking of the mutant laminin and rescuing misfolded 2 proteins to reach their functional destination are hopeful therapeutic strategies. The overall goal of this research is to investigate a novel strategy for therapeutic intervention in genetic forms of NS. To accomplish our research goal, we have generated a NS mouse model (Lamb2-/-; NEPH- C321R-LAMB2 mice) in which podocyte-targeted expression of the mutant form of rat LAMB2 (C321R-LAMB2) via the mouse nephrin promoter (NEPH) replaces the wild-type mouse LAMB2. Our preliminary data show that the misfolded mutant protein is much more susceptible to protein degradation, which is mediated by the ubiquitin-proteasome pathway. More excitingly, a combination of a chemical chaperone correcting protein misfolding and a proteasome inhibitor blocking protein degradation elicit a much more pronounced pro- secretion effect as compared to the chemical chaperone alone in vitro. Thus, the effect of combined treatment regulating both protein misfolding and degradation will be further investigated in our NS mouse model. The proposed study will assay the feasibility for therapeutic use of chemical chaperones in combination with proteasome inhibitors in a NS animal model. The results may have significant therapeutic implications for the treatment of familial or sporadic NS patients caused by aberrant ER proteostasis and podocyte ER dysfunction.

描述（由适用提供）：肾病综合征（NS）的特征是重蛋白尿，低藻症和增加肾功能丧失的风险增加。它导致严重的发病率和高死亡率，占美国普遍存在的末期肾脏疾病的15％，在美国的年费用超过30亿美元。对于大多数与基因突变相关的NS病例，没有有效的治疗方法。我们的研究集中在由LAMB2的错义突变引起的NS的单基因形式，LAMB2是NS中最常见的突变基因之一。 LAMB2编码的层粘连蛋白ß2是层粘连蛋白-521（α5ß2γ1）的成分，这是肾小球基底膜（GBM）的主要层粘连蛋白触发。使用我们已建立的细胞和基因敲除/转基因小鼠模型，我们发现抑制了从足细胞到GBM的c321R-LAMB2的分泌，以及由此产生的足细胞内质网应力（ER）胁迫导致蛋白尿。另外，GBM中突变体的积累增加减轻了蛋白尿。因此，恢复突变层粘连蛋白的有缺陷的贩运并营救了错误折叠的2种蛋白质以达到其功能性目的地，这是充满希望的治疗策略。这项研究的总体目标是研究NS遗传形式的治疗干预策略的新策略。为了实现我们的研究目标，我们已经生成了NS小鼠模型（LAMB2 - / - ; NEPH- C321R-LAMB2小鼠），其中大鼠羊羔2（C321R-LAMB2）突变形式的Podocyte-Target靶向表达通过小鼠肾蛋白启动子（NEPH）替代了野生型野生型小鼠LAMB 2。我们的初步数据表明，脱皮的突变蛋白更容易受到蛋白质降解的影响，蛋白质降解是由泛素 - 蛋白酶体途径介导的。更令人兴奋的是，与单独的体外化学链酮相比，化学链酮校正蛋白质错误折叠和蛋白酶体抑制剂阻断蛋白降解的组合会产生更明显的促尿液分泌效应。这是在我们的NS小鼠模型中进一步研究蛋白质错误折叠和降解的联合治疗调节的效果。拟议的研究将主张化学链酮与NS动物模型中蛋白酶体抑制剂结合使用的治疗性使用的可行性。该结果可能对因异常蛋白抑制剂和足球功能障碍引起的家庭或零星NS患者的治疗具有显着的治疗意义。