Effects of hypoxia on cell proliferation and cell survival and on gene expression profile of cytokines such as IL8, CCL8, IFNγ, TNF and IL10 , in human bone marrow derived mesenchymal stem cells

Abstract

Mesenchymal stem cells are Spindle-shaped cells with the ability of self-renewal and differentiation into various lineage and adherence to plastic surface. These cells can be derived from different tissues including: dental pulp, bone marrow, adipose tissue, endometrial, placenta and cord blood. Human mesenchymal stem cells (hMSCs) due to their ability to self-renewal and differentiation to various cell lineage, have created high hopes to cell and gene therapy. Oxygen is an important gene expression regulatory molecule in the animal tissues, and is one of the most important effective agents on stem cells regulation. Bone marrow derived human mesenchymal stem cells are adapted to low oxygen pressure at physiological condition while the oxygen concentration at in vitro cell culture medium is equal to atmosphere pressure that is 21%. The reaction of these cells in the transmission from the in vivo to in vitro condition or vice versa, affects their biological aspects. In this thesis the effect of hypoxia on gene expression of IL10, TNF, IFNγ, CCL8 and IL8 was investigated in vitro and compared to the results gained in normoxic contion.

Aim: The aim of this study was to evaluate the effects of hypoxia on expression level of bone marrow derived hMSCs secreted cytokines.

Materials and Methods: The cellular RNA is extracted and is transcripted to cDNA. The gene expression level was analyzed by the real-time PCR.

Results: The results of this study demonstrated that the hypoxia increased the gene expression of IFNγ and CCL8 in a dose depended manner in bone marrow derived mesenchymal stem cells. However the expression of TNF, IL10 and IL8 did not significantly changed in hypoxia condition.

Conclution: The hypoxia changes the cytokine expression profile of bone marrow derived hMSCs compared to normoxic condition in in vitro cultured cells dose dependently.