Project description:Podocyte injury in diabetic kidney disease contributes to the development of albuminuria and subsequent renal decline. Clinically, gastric bypass surgery is associated with reductions in albuminuria, and rodent studies demonstrate coherent improvements in renal histology. We aimed to investigate the mechanisms underpinning remission of albuminuria following gastric bypass focussing on podocyte injury. Firstly, we tracked the evolution of albuminuria and cognate evidence of histological and ultrastructural damage to the glomerulus in male Zucker Diabetic Fatty rats. Secondly, we examined the impact of gastric bypass in these rats, focussing on podocyte injury. Thirdly, we conducted a global transcriptomic study profiling the shift in the renal transcriptome in the Zucker Diabetic Fatty rats rat and its relevance to human disease. Lastly, we explored whether gastric bypass could reverse the changes seen in the disease associated transcriptome. Albuminuria in the Zucker Diabetic Fatty rat developed by 12 weeks of age. This was accompanied by glomerulomegaly, podocyte stress and ultrastructural evidence of podocyte dedifferentiation. When animals underwent gastric bypass at 12 weeks of age, marked reductions in albuminuria in association with normalisation of glomerular tuft size, attenuation of podocyte stress and improvements in podocyte foot process morphology were observed within 2 months of surgery. A characteristic disease associated gene expression signature was observed in the kidneys of Zucker Diabetic Fatty rats, with a core set of alterations conserved in global analysis of the human DKD transcriptome. Many of the shared gene expression alterations were reversed by gastric bypass. Reductions in podocyte injury represent a key mechanism underpinning the remission of albuminuria following gastric bypass.
Project description:Albuminuria is significantly reduced following Roux-en-Y gastric bypass (RYGB) surgery, suggesting a renoprotective effect of the intervention. Herein, we assess the relative impact of RYGB and RYGB equivalent non-surgical weight loss and glycaemic improvement on glomerular injury and global renal transcriptomic responses in the Zucker diabetic fatty rat (ZDF) model of diabetic nephropathy. We coined the term "medical bypass" (MB) to describe the intensive diet and pharmacotherapy based non-surgical intervention Adult ZDF rats underwent sham surgery (n=15) or RYGB (n=9). Nine sham-operated rats were calorie restricted and received insulin, liraglutide, metformin, ramipril, rosuvastatin and fenofibrate for 2 months (MB). Zucker fa/+ rats acted as healthy controls throughout. Bodyweight, glycaemia, albuminuria and glomerular injury specifically podocyte number, density and ultrastructure were assessed at follow up. Renal transcriptomes were compared by RNA-seq. RYGB resulted in 20-30% weight loss, normalized glycaemia and albuminuria and reduced indices of glomerular injury, specifically podocyte injury (foot process effacement). RYGB equivalent outcomes were obtained on all parameters following MB.
Project description:This SuperSeries is composed of the following subset Series: GSE30528: Transcriptome Analysis of Human Diabetic Kidney Disease (DKD Glomeruli vs. Control Glomeruli) GSE30529: Transcriptome Analysis of Human Diabetic Kidney Disease (DKD Tubuli vs. Control Tubuli) GSE30566: Transcriptome Analysis of Human Diabetic Kidney Disease (Control Glomeruli vs. Control Tubuli) Refer to individual Series
Project description:Analysis of gene expression changes in differentiated human podocytes treated with the serum from patients with (DKD+) or without (DKD-) diabetic kidney disease when compared to normal subjects (C). The hypothesis is that the three groups can be distinghed by their differential gene expression pattern. The results obtained revealed important information regarding differences in gene expression in human podocytes treated with the serum from patients with (DKD+) or without (DKD-) diabetic kidney disease when compared to normal subjects (C). Human podocytes were contacted with the serum from patients with diabetes and kidney disease (DKD+) or without kidney disease (DKD-) and compared to normal human podocytes contacted with serum from patients without diabetes (C).
Project description:Analysis of gene expression changes in differentiated human podocytes treated with the serum from patients with (DKD+) or without (DKD-) diabetic kidney disease when compared to normal subjects (C). The hypothesis is that the three groups can be distinghed by their differential gene expression pattern. The results obtained revealed important information regarding differences in gene expression in human podocytes treated with the serum from patients with (DKD+) or without (DKD-) diabetic kidney disease when compared to normal subjects (C). Human podocytes were contacted with the serum from patients with diabetes and kidney disease (DKD+) or without kidney disease (DKD-) and compared to normal human podocytes contacted with serum from patients without diabetes (C).
Project description:We report results from renal cortical transcriptomic analysis of responses to RYGB surgery alone and the combination of RYGB surgery and medical therapy in the Zucker Diabetic Sprague Dawley (ZDSD) rat model of diabetic kidney disease.
Project description:Since the etiology of diabetic chronic kidney disease (CKD) is multifactorial, studies on DNA methylation for kidney function deterioration have rarely been performed despite the need for an epigenetic approach. Therefore, this study aimed to identify epigenetic markers associated with CKD progression based on the decline in the estimated glomerular filtration rate in diabetic CKD in Korea.
