Effects Of Hypoxia in Long‐Term In Vitro Expansion of Human Bone Marrow Derived Mesenchymal Stem Cells

• Published in: Journal of cellular biochemistry Vol. 118; no. 10; pp. 3072 - 3079
• Main Authors: Pezzi, Annelise, Amorin, Bruna, Laureano, Álvaro, Valim, Vanessa, Dahmer, Alice, Zambonato, Bruna, Sehn, Filipe, Wilke, Ianaê, Bruschi, Lia, Silva, Maria Aparecida Lima da, Filippi‐Chiela, Eduardo, Silla, Lucia
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.10.2017
• Subjects: AUTOPHAGY; Bone marrow; Bone Marrow Cells - cytology; Bone Marrow Cells - metabolism; Bone marrow transplantation; Cell culture; Cell Culture Techniques; Cell Hypoxia; Cell proliferation; Cell size; Complexity; Cultivation; Differentiation; Female; Heterogeneity; Humans; HYPOXIA; In vitro methods and tests; Male; MESENCHYMAL STEM CELL; Mesenchymal stem cells; Mesenchymal Stromal Cells - cytology; Mesenchymal Stromal Cells - metabolism; Mesenchyme; Mitochondria; Mitochondria - metabolism; MITOCHONDRIAL ACTIVITY; Optimization; Oxidative stress; Oxygen; Oxygen Consumption; Oxygen tension; Phagocytosis; Physical characteristics; Plastic foam; REACTIVE OXYGEN SPECIES; Stem cell transplantation; Stem cells; Time Factors; REACTIVE OXYGEN SPECIES; AUTOPHAGY; MITOCHONDRIAL ACTIVITY; HYPOXIA; MESENCHYMAL STEM CELL
• DOI: 10.1002/jcb.25953
• ISSN: 0730-2312; 1097-4644

ABSTRACT Mesenchymal stem cells (MSC) are considered multipotent stromal, non‐hematopoietic cells with properties of self‐renovation and differentiation. Optimal conditions for culture of MSC have been under investigation. The oxygen tension used for cultivation has been studied and appears to play an important role in biological behavior of mesenchymal cells. The aim is characterize MSC in hypoxia and normoxia conditions comparing their morphological and functional characteristics. Bone marrow‐derived mesenchymal stem cells obtained from 15 healthy donors and cultured. MSC obtained from each donor were separated into two cultivation conditions normoxia (21% O2) and hypoxia (three donors at 1%, three donors at 2%, five donors at 3%, and four donors at 4% O2) up to second passage. MSC were evaluated for proliferation, differentiation, immunophenotyping, size and cell complexity, oxidative stress, mitochondrial activity, and autophagy. Culture conditions applied did not seem to affect immunophenotypic features and cellular plasticity. However, cells subjected to hypoxia showed smaller size and greater cellular complexity, besides lower proliferation (P < 0.002). Furthermore, cells cultured in low O2 tension had lower mitochondrial activity (P < 0.03) and a reduced tendency to autophagy, although oxidative stress did not vary among groups (P < 0.39). Oxygen tension seems to be a key regulator of cellular adaptation in vitro, and metabolic effects underlying this variable remain undescribed. Heterogeneity or even lack of results on the impact of oxygen concentration used for expanding MSC highlights the need for further research, in order to optimize conditions of cultivation and expansion and achieve greater safety and therapeutic efficacy. J. Cell. Biochem. 118: 3072–3079, 2017. © 2017 Wiley Periodicals, Inc. Cells subjected to hypoxia showed smaller size and greater cellular complexity, besides lower proliferation (P < 0.002). Furthermore, cells cultured in low O2 tension had lower mitochondrial activity (P < 0.03) and a reduced tendency to autophagy, although oxidative stress did not vary among groups (P < 0.39).