Dimethyl-2-oxoglutarate improves redox balance and mitochondrial function in muscle pericytes of individuals with diabetes mellitus

Faulkner, A; Tamiato, A; Cathery, W; Rampin, A; Caravaggi, C M; Jover, E; Allen, S; Mellor, H; Hauton, D; Heather, L C; Spinetti, G; Madeddu, P

Abstract

Aims/hypothesis Treatment of vascular complications of diabetes remains inadequate. We reported that muscle pericytes (MPs) from limb muscles of vascular patients with diabetes mellitus display elevated levels of oxidative stress causing a dysfunctional phenotype. Here, we investigated whether treatment with dimethyl-2-oxoglutarate (DM-2OG), a tricarboxylic acid cycle metab- olite with antioxidant properties, can restore a healthy metabolic and functional phenotype.
Methods MPs were isolated from limb muscles of diabetes patients with vascular disease (D-MPs) and from non-diabetic control participants (ND-MPs). Metabolic status was assessed in untreated and DM-2OG-treated (1 mmol/l) cells using an extracellular flux analyser and anion-exchange chromatography–mass spectrometry (IC-MS/MS). Redox status was measured using commercial kits and IC-MS/MS, with antioxidant and metabolic enzyme expression assessed by quanti- tative RT-PCR and western blotting. Myogenic differentiation and proliferation and pericyte–endothelial interaction were assessed as functional readouts.
Results D-MPs showed mitochondrial dysfunction, suppressed glycolytic activity and reduced reactive oxygen species- buffering capacity, but no suppression of antioxidant systems when compared with ND-MP controls. DM-2OG supple- mentation improved redox balance and mitochondrial function, without affecting glycolysis or antioxidant systems. Nonetheless, this was not enough for treated D-MPs to regain the level of proliferation and myogenic differentiation of ND-MPs. Interestingly, DM-2OG exerted a positive effect on pericyte–endothelial cell interaction in the co-culture angiogenesis assay, independent of the diabetic status.
Conclusions/interpretation These novel findings support the concept of using DM-2OG supplementation to improve pericyte redox balance and mitochondrial function, while concurrently allowing for enhanced pericyte–endothelial crosstalk. Such effects may help to prevent or slow down vasculopathy in skeletal muscles of people with diabetes.

Citation

Faulkner, A., Tamiato, A., Cathery, W., Rampin, A., Caravaggi, C. M., Jover, E., …Madeddu, P. (2020). Dimethyl-2-oxoglutarate improves redox balance and mitochondrial function in muscle pericytes of individuals with diabetes mellitus. Diabetologia, 63(10), 2205-2217

• Journal Article Type: Article
• Acceptance Date: May 22, 2020
• Publication Date: Jul 30, 2020
• Deposit Date: Sep 11, 2020
• Publicly Available Date: Sep 11, 2020
• Journal: Diabetologia
• Print ISSN: 0012-186X
• Publisher: Springer
• Peer Reviewed: Peer Reviewed
• Volume: 63
• Issue: 10
• Pages: 2205-2217
• Public URL: https://rvc-repository.worktribe.com/output/1376526
• Publisher URL: https://doi.org/10.1007/s00125-020-05230-4