Adipose-Derived Stem Cells Conditioned Media Promote In Vitro Osteogenic Differentiation of Hypothyroid Mesenchymal Stem Cells

Thyroid hormones have many effects on the physiological functions of cells, including growth, differentiation, and metabolism.

Recently, studies have shown that the adipose-derived mesenchymal stem cells conditioned medium (ADMSCs-CM) has many osteogenic factors, such as IGF-1, IL-6, and FGFs.

In the current study, mesenchymal stem cells (MSCs) were isolated from two sources; the adipose tissue of the testicular fat pad and the bone marrow of rat, and then characterized by flow cytometry. ADMSCs-CM was collected from the ADMSC in the healthy adult male rats. Hypothyroidism was induced by the administration of the Methimazole during 60 days and confirmed by the analysis of the serum level of T4 and TSH hormones. Cell proliferation and osteogenic differentiation potential of bone marrow stem cells (BMSCs) derived from hypothyroid rats were investigated in the presence and absence of the CM by MTT assay, alkaline phosphatase (ALP) activity, calcium content assay, and bone-related gene expression. Healthy BMSCs were assigned to the control group.

Although Cell proliferation was decreased in the hypothyroid BMSCs, there was no significant difference between the control and the hypothyroid-CM groups. Similarly, osteogenic potential was significantly reduced in the hypothyroid group compared to the control and hypothyroid-CM groups according to the ALP, calcium content assays, and gene expression results. There was no significant difference between the hypothyroid-CM group and control.

Our results indicated that hypothyroidism can decrease cell proliferation and osteogenic differentiation of BMSCs. Although ADMSCs-CM improved these parameters, it may be a promising candidate for the bone regeneration of the hypothyroidism cases.