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Increased oxygen consumption and OXPHOS potential in superhealer mesenchymal stem cells.

Hughey CC, Alfaro MP, Belke DD, Rottman JN, Young PP, Wasserman DH, Shearer J - Cell Regen (Lond) (2012)

Bottom Line: Additionally, glutamate/malate succinate-supported oxygen consumption in permeabilized cells was elevated approximately 1.25- and 1.4-fold in the MRL-MSCs, respectively.The results from intact and permeabilized MSCs indicate MRL-MSCs exhibit a greater reliance on and capacity for aerobic metabolism.The greater capacity for oxidative metabolism may provide a protective effect by increasing ATP synthesis per unit substrate and prevent glycolysis-mediated acidosis and subsequent cell death upon transplantation into the glucose-and oxygen-deprived environment of the infarcted heart.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Calgary, Calgary, AB T2N 1N4 Canada ; University of Calgary, KNB Rm 3318. 2500 University Dr. NW, Calgary, Alberta Canada T2N 1N4.

ABSTRACT

Background: Cell-based therapies show promise in repairing cardiac tissue and improving contractile performance following a myocardial infarction. Despite this, ischemia-induced death of transplanted cells remains a major hurdle to the efficacy of treatment. 'Superhealer' MRL/MpJ mesenchymal stem cells (MRL-MSCs) have been reported to exhibit increased engraftment resulting in reduced infarct size and enhanced contractile function. This study determines whether intrinsic differences in mitochondrial oxidative phosphorylation (OXPHOS) assist in explaining the enhanced cellular survival and engraftment of MRL-MSCs.

Findings: Compared to wild type MSCs (WT-MSCs), mitochondria from intact MRL-MSCs exhibited an increase in routine respiration and maximal electron transport capacity by 2.0- and 3.5-fold, respectively. When routine oxygen utilization is expressed as a portion of maximal cellular oxygen flux, the MRL-MSCs have a greater spare respiratory capcity. Additionally, glutamate/malate succinate-supported oxygen consumption in permeabilized cells was elevated approximately 1.25- and 1.4-fold in the MRL-MSCs, respectively.

Conclusion: The results from intact and permeabilized MSCs indicate MRL-MSCs exhibit a greater reliance on and capacity for aerobic metabolism. The greater capacity for oxidative metabolism may provide a protective effect by increasing ATP synthesis per unit substrate and prevent glycolysis-mediated acidosis and subsequent cell death upon transplantation into the glucose-and oxygen-deprived environment of the infarcted heart.

No MeSH data available.


Related in: MedlinePlus

Oxygen flux in permeabilized wild-type mesenchymal stem cells (WT-MSC) and MRL/MpJ mesenchymal stem cells (MRL-MSC). (A) Routine respiration in MiR05 (RMiR05) in intact MSCs. State 2 oxygen consumption through Complex I supported by glutamate and malate (VCI) in digitoin-permabilized MSCs. State 3 or maximal oxygen consumption through Complex I supported by glutamate and malate (VMAX-CI) in digitoin-permabilized MSCs. State 3 or maximal oxygen consumption through Complex II supported by succinate (VMAX-CII) in digitoin-permabilized MSCs. (B) Given MSCs are transplanted into the infarcted heart, isolated, primary cardiac myocyte oxygen utilization is provided as a metabolic reference state. Cardiac myocyte state 2 oxygen consumption through Complex I supported by glutamate and malate (VCI) in digitoin-permabilized cardiac myocytes. State 3 or maximal oxygen consumption through Complex I supported by glutamate and malate (VMAX-CI) in digitoin-permabilized cardiac myocytes. State 3 or maximal oxygen consumption through Complex II supported by succinate (VMAX-CII) in digitoin-permabilized cardiac myocytes. (C) Acceptor control ratio (ACR; defined as VMAX-CI/VCI). n = 6-9, data are mean ± S.E.M. *p < 0.05 vs. WT-MSC. †p < 0.05 vs. MRL-MSC
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Fig2: Oxygen flux in permeabilized wild-type mesenchymal stem cells (WT-MSC) and MRL/MpJ mesenchymal stem cells (MRL-MSC). (A) Routine respiration in MiR05 (RMiR05) in intact MSCs. State 2 oxygen consumption through Complex I supported by glutamate and malate (VCI) in digitoin-permabilized MSCs. State 3 or maximal oxygen consumption through Complex I supported by glutamate and malate (VMAX-CI) in digitoin-permabilized MSCs. State 3 or maximal oxygen consumption through Complex II supported by succinate (VMAX-CII) in digitoin-permabilized MSCs. (B) Given MSCs are transplanted into the infarcted heart, isolated, primary cardiac myocyte oxygen utilization is provided as a metabolic reference state. Cardiac myocyte state 2 oxygen consumption through Complex I supported by glutamate and malate (VCI) in digitoin-permabilized cardiac myocytes. State 3 or maximal oxygen consumption through Complex I supported by glutamate and malate (VMAX-CI) in digitoin-permabilized cardiac myocytes. State 3 or maximal oxygen consumption through Complex II supported by succinate (VMAX-CII) in digitoin-permabilized cardiac myocytes. (C) Acceptor control ratio (ACR; defined as VMAX-CI/VCI). n = 6-9, data are mean ± S.E.M. *p < 0.05 vs. WT-MSC. †p < 0.05 vs. MRL-MSC

Mentions: Oxygen consumption in permeabilized cells was evaluated to obtain a greater understanding of the OXPHOS function. Suspension of intact MSCs in MiR05 did not change routine respiration. RMiR05 remained significantly lower in the WT-MSCs, 37.3 ± 4.7 vs. 63.5 ± 3.3 pmol O2/s/106 cells (Figure 2A). State 2 respiration (VCI), was similar between WT- and MRL-MSCs. WT-MSC state 2 respiration was 11.4 ± 0.6 pmol O2/s/106 cells compared to the MRL-MSC respiration of 21.8 ± 2.7 pmol O2/s 106 cells (Figure 2A). Following the addition of ADP, state 3 (VMAX-CI) was lower in the WT-MSCs compared to the MRL-MSCs, 90.0 ± 13.0 vs. 112.0 ± 2.7 pmol O2/s/106 cells (Figure 2A). In addition, state 3 in WT-MSCs supported by succinate alone (VMAX-CII) was 102.0 ± 2.8 pmol O2/s/106 cells. This was significantly lower than the VMAX-CII exhibited by MRL-MSCs, 140.1 ± 5.7 pmol O2/s/106 cells (Figure 2A). As a comparison, isolated cardiac myocyte oxygen flux was higher than that of both WT- and MRL-MSCs. Isolated, cardiac myocyte VCI, VMAX-CI and VMAX-CII were 1.44 ± 0.24, 6.84 ± 1.08 and 18.33 ± 2.18 nmol O2/s/106 cells, respectively (Inset, Figure 2B). Additionally, the ACR did not differ between WT- and MRL-MSCs (Figure 2C).Figure 2


Increased oxygen consumption and OXPHOS potential in superhealer mesenchymal stem cells.

Hughey CC, Alfaro MP, Belke DD, Rottman JN, Young PP, Wasserman DH, Shearer J - Cell Regen (Lond) (2012)

Oxygen flux in permeabilized wild-type mesenchymal stem cells (WT-MSC) and MRL/MpJ mesenchymal stem cells (MRL-MSC). (A) Routine respiration in MiR05 (RMiR05) in intact MSCs. State 2 oxygen consumption through Complex I supported by glutamate and malate (VCI) in digitoin-permabilized MSCs. State 3 or maximal oxygen consumption through Complex I supported by glutamate and malate (VMAX-CI) in digitoin-permabilized MSCs. State 3 or maximal oxygen consumption through Complex II supported by succinate (VMAX-CII) in digitoin-permabilized MSCs. (B) Given MSCs are transplanted into the infarcted heart, isolated, primary cardiac myocyte oxygen utilization is provided as a metabolic reference state. Cardiac myocyte state 2 oxygen consumption through Complex I supported by glutamate and malate (VCI) in digitoin-permabilized cardiac myocytes. State 3 or maximal oxygen consumption through Complex I supported by glutamate and malate (VMAX-CI) in digitoin-permabilized cardiac myocytes. State 3 or maximal oxygen consumption through Complex II supported by succinate (VMAX-CII) in digitoin-permabilized cardiac myocytes. (C) Acceptor control ratio (ACR; defined as VMAX-CI/VCI). n = 6-9, data are mean ± S.E.M. *p < 0.05 vs. WT-MSC. †p < 0.05 vs. MRL-MSC
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4230749&req=5

Fig2: Oxygen flux in permeabilized wild-type mesenchymal stem cells (WT-MSC) and MRL/MpJ mesenchymal stem cells (MRL-MSC). (A) Routine respiration in MiR05 (RMiR05) in intact MSCs. State 2 oxygen consumption through Complex I supported by glutamate and malate (VCI) in digitoin-permabilized MSCs. State 3 or maximal oxygen consumption through Complex I supported by glutamate and malate (VMAX-CI) in digitoin-permabilized MSCs. State 3 or maximal oxygen consumption through Complex II supported by succinate (VMAX-CII) in digitoin-permabilized MSCs. (B) Given MSCs are transplanted into the infarcted heart, isolated, primary cardiac myocyte oxygen utilization is provided as a metabolic reference state. Cardiac myocyte state 2 oxygen consumption through Complex I supported by glutamate and malate (VCI) in digitoin-permabilized cardiac myocytes. State 3 or maximal oxygen consumption through Complex I supported by glutamate and malate (VMAX-CI) in digitoin-permabilized cardiac myocytes. State 3 or maximal oxygen consumption through Complex II supported by succinate (VMAX-CII) in digitoin-permabilized cardiac myocytes. (C) Acceptor control ratio (ACR; defined as VMAX-CI/VCI). n = 6-9, data are mean ± S.E.M. *p < 0.05 vs. WT-MSC. †p < 0.05 vs. MRL-MSC
Mentions: Oxygen consumption in permeabilized cells was evaluated to obtain a greater understanding of the OXPHOS function. Suspension of intact MSCs in MiR05 did not change routine respiration. RMiR05 remained significantly lower in the WT-MSCs, 37.3 ± 4.7 vs. 63.5 ± 3.3 pmol O2/s/106 cells (Figure 2A). State 2 respiration (VCI), was similar between WT- and MRL-MSCs. WT-MSC state 2 respiration was 11.4 ± 0.6 pmol O2/s/106 cells compared to the MRL-MSC respiration of 21.8 ± 2.7 pmol O2/s 106 cells (Figure 2A). Following the addition of ADP, state 3 (VMAX-CI) was lower in the WT-MSCs compared to the MRL-MSCs, 90.0 ± 13.0 vs. 112.0 ± 2.7 pmol O2/s/106 cells (Figure 2A). In addition, state 3 in WT-MSCs supported by succinate alone (VMAX-CII) was 102.0 ± 2.8 pmol O2/s/106 cells. This was significantly lower than the VMAX-CII exhibited by MRL-MSCs, 140.1 ± 5.7 pmol O2/s/106 cells (Figure 2A). As a comparison, isolated cardiac myocyte oxygen flux was higher than that of both WT- and MRL-MSCs. Isolated, cardiac myocyte VCI, VMAX-CI and VMAX-CII were 1.44 ± 0.24, 6.84 ± 1.08 and 18.33 ± 2.18 nmol O2/s/106 cells, respectively (Inset, Figure 2B). Additionally, the ACR did not differ between WT- and MRL-MSCs (Figure 2C).Figure 2

Bottom Line: Additionally, glutamate/malate succinate-supported oxygen consumption in permeabilized cells was elevated approximately 1.25- and 1.4-fold in the MRL-MSCs, respectively.The results from intact and permeabilized MSCs indicate MRL-MSCs exhibit a greater reliance on and capacity for aerobic metabolism.The greater capacity for oxidative metabolism may provide a protective effect by increasing ATP synthesis per unit substrate and prevent glycolysis-mediated acidosis and subsequent cell death upon transplantation into the glucose-and oxygen-deprived environment of the infarcted heart.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Calgary, Calgary, AB T2N 1N4 Canada ; University of Calgary, KNB Rm 3318. 2500 University Dr. NW, Calgary, Alberta Canada T2N 1N4.

ABSTRACT

Background: Cell-based therapies show promise in repairing cardiac tissue and improving contractile performance following a myocardial infarction. Despite this, ischemia-induced death of transplanted cells remains a major hurdle to the efficacy of treatment. 'Superhealer' MRL/MpJ mesenchymal stem cells (MRL-MSCs) have been reported to exhibit increased engraftment resulting in reduced infarct size and enhanced contractile function. This study determines whether intrinsic differences in mitochondrial oxidative phosphorylation (OXPHOS) assist in explaining the enhanced cellular survival and engraftment of MRL-MSCs.

Findings: Compared to wild type MSCs (WT-MSCs), mitochondria from intact MRL-MSCs exhibited an increase in routine respiration and maximal electron transport capacity by 2.0- and 3.5-fold, respectively. When routine oxygen utilization is expressed as a portion of maximal cellular oxygen flux, the MRL-MSCs have a greater spare respiratory capcity. Additionally, glutamate/malate succinate-supported oxygen consumption in permeabilized cells was elevated approximately 1.25- and 1.4-fold in the MRL-MSCs, respectively.

Conclusion: The results from intact and permeabilized MSCs indicate MRL-MSCs exhibit a greater reliance on and capacity for aerobic metabolism. The greater capacity for oxidative metabolism may provide a protective effect by increasing ATP synthesis per unit substrate and prevent glycolysis-mediated acidosis and subsequent cell death upon transplantation into the glucose-and oxygen-deprived environment of the infarcted heart.

No MeSH data available.


Related in: MedlinePlus