Effect of hypoxia on equine mesenchymal stem cells derived from bone marrow and adipose tissue.
BACKGROUND
Mesenchymal stem cells (MSCs) derived from bone marrow (BM-MSCs) and adipose tissue (AT-MSCs) are being applied to equine cell therapy. The physiological environment in which MSCs reside is hypoxic and does not resemble the oxygen level typically used in in vitro culture (20% O2). This work compares the growth kinetics, viability, cell cycle, phenotype and expression of pluripotency markers in both equine BM-MSCs and AT-MSCs at 5% and 20% O2.


RESULTS
At the conclusion of culture, fewer BM-MSCs were obtained in hypoxia than in normoxia as a result of significantly reduced cell division. Hypoxic AT-MSCs proliferated less than normoxic AT-MSCs because of a significantly higher presence of non-viable cells during culture. Flow cytometry analysis revealed that the immunophenotype of both MSCs was maintained in both oxygen conditions. Gene expression analysis using RT-qPCR showed that statistically significant differences were only found for CD49d in BM-MSCs and CD44 in AT-MSCs. Similar gene expression patterns were observed at both 5% and 20% O2 for the remaining surface markers. Equine MSCs expressed the embryonic markers NANOG, OCT4 and SOX2 in both oxygen conditions. Additionally, hypoxic cells tended to display higher expression, which might indicate that hypoxia retains equine MSCs in an undifferentiated state.


CONCLUSIONS
Hypoxia attenuates the proliferative capacity of equine MSCs, but does not affect the phenotype and seems to keep them more undifferentiated than normoxic MSCs.
Laboratorio de Genética Bioquímica, Facultad de Veterinaria, Universidad de Zaragoza, 50013 Zaragoza, Spain.
Beatriz
B
Ranera
Ana Rosa
AR
Remacha
Samuel
S
Álvarez-Arguedas
Antonio
A
Romero
Francisco José
FJ
Vázquez
Pilar
P
Zaragoza
Inmaculada
I
Martín-Burriel
Clementina
C
Rodellar
D000818:Animals; D015415:Biomarkers; D001854:Bone Marrow Cells / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D018929:Cell Culture Techniques; D002455:Cell Division / Q000187:drug effects; D049109:Cell Proliferation; D002470:Cell Survival; D005786:Gene Expression Regulation / Q000187:drug effects; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D010100:Oxygen / Q000494:pharmacology*
D015415:Biomarkers; D008565:Membrane Proteins; D010100:Oxygen