Medications Activating Tubular Fatty Acid Oxidation Enhance the Protective Effects of Roux-en-Y Gastric Bypass Surgery in a Rat Model of Early Diabetic Kidney Disease

• Published in: Frontiers in endocrinology (Lausanne) Vol. 12; p. 757228
• Main Authors: Martin, William P, Chuah, Yeong H D, Abdelaal, Mahmoud, Pedersen, Anders, Malmodin, Daniel, Abrahamsson, Sanna, Hutter, Michaela, Godson, Catherine, Brennan, Eoin P, Fändriks, Lars, le Roux, Carel W, Docherty, Neil G
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 26.01.2022
• Subjects: animal experiment; animal model; animal tissue; Animals; bariatric surgery; bioinformatics; controlled study; Diabetes Mellitus; diabetic kidney disease; Diabetic Nephropathies - etiology; Diabetic Nephropathies - genetics; diabetic nephropathy; disease severity; down regulation; Endocrinology; Endocrinology and Diabetes; Endokrinologi och diabetes; epithelium cell; fatty acid oxidation; Fatty Acids; fenofibrate; Fontan procedure; Gastric Bypass - methods; gastric bypass surgery; gene expression; gene ontology; genetic transcription; glomerulus basement membrane; glycemic control; glycolysis; hemodynamics; hypertension; immunohistochemistry; kidney biopsy; kidney cortex tissue; lipid composition; lipid metabolism; male; messenger RNA; metabolic regulation; metabolome; metabolomics; metformin; mitochondria; mitochondrial biogenesis; mitochondrial respiration; morphometry; nonhuman; nuclear RNA; peroxisome; peroxisome proliferator activated receptor alpha; podocyte; PPAR-alpha; prevalence; proteomics; proton nuclear magnetic resonance; quality control; ramipril; rat; Rats; Rats, Sprague-Dawley; Rats, Zucker; real time polymerase chain reaction; risk factor; RNA sequencing; rosuvastatin; Roux-en-Y gastric bypass; Sprague Dawley rat; transcription initiation; transcriptome; transcriptomics; transmission electron microscopy; treatment response; triacylglycerol; upregulation; Zucker diabetic fatty rat; diabetic kidney disease; bariatric surgery; mitochondria; transcriptome; PPAR-alpha; peroxisome; fatty acid oxidation; metabolome
• ISSN: 1664-2392; 1664-2392
• DOI: 10.3389/fendo.2021.757228

Roux-en-Y gastric bypass surgery (RYGB) improves biochemical and histological parameters of diabetic kidney disease (DKD). Targeted adjunct medical therapy may enhance renoprotection following RYGB. The effects of RYGB and RYGB plus fenofibrate, metformin, ramipril, and rosuvastatin (RYGB-FMRR) on metabolic control and histological and ultrastructural indices of glomerular and proximal tubular injury were compared in the Zucker Diabetic Sprague Dawley (ZDSD) rat model of DKD. Renal cortical transcriptomic (RNA-sequencing) and urinary metabolomic ( H-NMR spectroscopy) responses were profiled and integrated. Transcripts were assigned to kidney cell types through deconvolution in kidney single-nucleus RNA-sequencing and microdissected tubular epithelial cell proteomics datasets. Medication-specific transcriptomic responses following RYGB-FMRR were explored using a network pharmacology approach. Omic correlates of improvements in structural and ultrastructural indices of renal injury were defined using a molecular morphometric approach. RYGB-FMRR was superior to RYGB alone with respect to metabolic control, albuminuria, and histological and ultrastructural indices of glomerular injury. RYGB-FMRR reversed DKD-associated changes in mitochondrial morphology in the proximal tubule to a greater extent than RYGB. Attenuation of transcriptomic pathway level activation of pro-fibrotic responses was greater after RYGB-FMRR than RYGB. Fenofibrate was found to be the principal medication effector of gene expression changes following RYGB-FMRR, which led to the transcriptional induction of PPARα-regulated genes that are predominantly expressed in the proximal tubule and which regulate peroxisomal and mitochondrial fatty acid oxidation (FAO). After omics integration, expression of these FAO transcripts positively correlated with urinary levels of PPARα-regulated nicotinamide metabolites and negatively correlated with urinary tricarboxylic acid (TCA) cycle intermediates. Changes in FAO transcripts and nicotinamide and TCA cycle metabolites following RYGB-FMRR correlated strongly with improvements in glomerular and proximal tubular injury. Integrative multi-omic analyses point to PPARα-stimulated FAO in the proximal tubule as a dominant effector of treatment response to combined surgical and medical therapy in experimental DKD. Synergism between RYGB and pharmacological stimulation of FAO represents a promising combinatorial approach to the treatment of DKD in the setting of obesity.