Diabetes is a complex multifactorial disorder associated with hyperglycemia, oxidative stress, and inflammation. The pathological microenvironment impairs mesenchymal stem cell (MSC) viability and dysregulates their proregenerative and immune-modulatory function causing maladaptive tissue damage. Targeting stem cells to protect them against impairment could thus delay the onset of complications and enhance the quality of life in diabetes mellitus patients. The aim of this study was to investigate the efficacy of N-acetylcysteine (NAC) and ascorbic-acid-2-phosphate (AAP) oral supplementation as preventative measure against MSC impairment. Healthy wild-type control (C57BL/6J) (male, n = 24) and obese diabetic (B6.C-Lepob/J) (ob/ob) (male, n = 24) mice received either placebo or antioxidant (NAC/AAP) supplementation for a period of 6 weeks. Metabolic parameters (weight and blood glucose) and the oxidative status (serum total serum antioxidant capacity, malondialdehyde) of animals were assessed. At the end of the 6-week supplementation period, bone marrow MSCs were isolated and their functionality (growth rate, viability, adipogenesis, and osteogenesis) assessed ex vivo. Real time quantitative polymerase chain reaction microarray analysis was also performed to assess the expression of 84 genes related to oxidative stress in MSCs. Despite no change in the metabolic profile, NAC/AAP supplementation improved the antioxidant status of diabetic animals and reduced lipid peroxidation, which is indicative of cellular damage. NAC/AAP also improved the population doubling time of MSCs (first 6-days postisolation) and significantly downregulated the expression of two genes (Nox1 and Rag2) associated with oxidative stress compared to placebo treatment. Taken together, this study has shown reduced oxidative stress and improvements in MSC function following in vivo antioxidant supplementation in healthy control and type 2 diabetic mice.
Keywords: Nox1; Rag2; antioxidants; diabetes; mesenchymal stem cells; oxidative stress.