Equine metabolic syndrome impairs adipose stem cells osteogenic differentiation by predominance of autophagy over selective mitophagy

Abstract

Adipose‐derived mesenchymal stem cells (ASC) hold great promise in the treatment of many disorders including musculoskeletal system, cardiovascular and/or endocrine diseases. However, the cytophysiological condition of cells, used for engraftment seems to be fundamental factor that might determine the effectiveness of clinical therapy. In this study we investigated growth kinetics, senescence, accumulation of oxidative stress factors, mitochondrial biogenesis, autophagy and osteogenic differentiation potential of ASC isolated from horses suffered from equine metabolic syndrome (EMS). We demonstrated that EMS condition impairs multipotency/pluripotency in ASCs causes accumulation of reactive oxygen species and mitochondria deterioration. We found that, cytochrome c is released from mitochondria to the cytoplasm suggesting activation of intrinsic apoptotic pathway in those cells. Moreover, we observed up‐regulation of p21 and decreased ratio of Bcl‐2/BAX. Deteriorations in mitochondria structure caused alternations in osteogenic differentiation of ASCEMS resulting in their decreased proliferation rate and reduced expression of osteogenic markers BMP‐2 and collagen type I. During osteogenic differentiation of ASCEMS, we observed autophagic turnover as probably, an alternative way to generate adenosine triphosphate and amino acids required to increased protein synthesis during differentiation. Downregulation of PGC1α, PARKIN and PDK4 in differentiated ASCEMS confirmed impairments in mitochondrial biogenesis and function. Hence, application of ASCEMS into endocrinological or ortophedical practice requires further investigation and analysis in the context of safeness of their application.

Macroautophagy and Selective Mitophagy Ameliorate Chondrogenic Differentiation Potential in Adipose Stem Cells of Equine Metabolic Syndrome: New Findings in the Field of Progenitor Cells Differentiation

“…It is tempting to speculate that similar, paradox, mechanism is switched on in EMS horses, standing as an adaptation to help animals maintain their metabolic help. Moreover, feeding mice on high-fat diet accelerated FGF21 beneficial effect; thus activating FGF21 by deteriorated mitochondria may be indeed the protective mechanism in individuals suffering from diabetes and metabolic syndrome, especially the fact that mitochondrial dysfunction in both of these diseases was proved in many studies [10, 31–33]. …”

Combination of resveratrol and 5‐azacytydine improves osteogenesis of metabolic syndrome mesenchymal stem cells

“…This hypothesis may be supported by PARKIN knockdown, which resulted in the down‐regulation of RUNX and Coll‐1; this in turn underlines its role in the course of osteogenic differentiation. Our previous research demonstrated that ASC EMS had impaired mitophagy, as decreased PGC1α, PARKIN and PDK4 activities together with reduced osteogenic differentiation potential were recorded 28. Thus, the obtained data indicate that pre‐treatment of ASC EMS with AZA/RES enhances osteogenic properties of these cells via increased mitophagy.…”

“…It was demonstrated that excessive accumulation of OS factors, ie ROS and NO, together with significantly decreased antioxidant protection, might be associated with reduced osteogenic differentiation potential and extracellular matrix formation 28, 33. In turn, many studies including ours, have shown that RES significantly attenuates OS by modulating SOD activity and mitochondrial dynamics 34, 35, 36.…”

“…##P < .01, ###P < .001, *P < .05, ***P < .001 osteogenic differentiation potential and extracellular matrix formation. 28,33 In turn, many studies including ours, have shown that RES significantly attenuates OS by modulating SOD activity and mitochondrial dynamics. [34][35][36] Consistent with these studies, we observed that the ex vivo application of AZA/RES significantly reduced the level of both ROS and NO.…”

“…Previous studies have shown that ASCs isolated from EMS horses (ASC EMS ) suffered from reduced proliferative activity, progressive apoptosis, ageing and senescence, which eventually impaired their multipotency and osteogenic differentiation potential. [27][28][29] It was shown that ASCs EMS exhibited reduced secretion of extracellular microvesicels (ExMVs) rich in bone morphogenetic protein 2 (BMP-2), collagen type II (COll-2) or osteocalcin (OCN)-all fundamental for ontogenesis. Deterioration of differentiation potential was caused by dysfunction of mitochondrial metabolism and dynamics.…”