Oxytocin improves the expression of cardiac specific markers in porcine bone marrow stem cells differentiation

DNA methyltransferase inhibitor 5-azacytidine in high dose promotes ultrastructural maturation of cardiomyocyte

Background

The adult human heart muscle cells, cardiomyocytes are not capable of regenerate after injury. Stem cells are a powerful means for future regenerative medicine because of their capacity for self-renewal and multipotency. Several studies have reported the cardiogenic potential in human adipose tissue-derived stem cells (ADSCs) differentiation, but there is still no efficient protocol for the induction of cardiac differentiation by 5-azacytidine (5-Aza). The present study involves characterization and mainly, the ultrastructure of ADSCs derived cardiomyocyte-like cells.

Methods

The cultured ADSCs were treated with 50 µM 5-Aza for 24 hours, followed by a 10-week extension. At different time points, cardiomyocyte-like cells were assessed by qRT-PCR and were evaluated by transmission electron microscopy at 10^th week.

Results

The expression of cardiac-specific markers entailing cardiac troponin I (cTnI), connexin 43, myosin light chain-2v (Mlc-2v), increased over 10 weeks and the highest expression was at 10^th week. The expression of the β-myosin heavy chain (β-MHC) increased significantly over 5 weeks and then decreased. At the ultrastructural level myofibrils, transverse tubules (T-tubules), sarcoplasmic reticular membrane, and intercalated discs were present.

Conclusions

These data suggest that treatment with 5-Aza in high dose could promote differentiation of ADSCs into cardiomyocyte-like cells. These differentiated cells could be used for regeneration of damaged cardiomyocytes with the 3D scaffold for delivery of the cells.

Influence of the Type of Delivery, Use of Oxytocin, and Maternal Age on POU5F1 Gene Expression in Stem Cells Derived from Wharton's Jelly within the Umbilical Cord

The paper presents an evaluation of the POU5F1 gene expression in mesenchymal stem cells derived from Wharton's jelly within the umbilical cord, collected from 36 patients during labor. The study is the first one to show that the expression of POU5F1 in mesenchymal stem cells has been dependent on maternal age, birth order, route of delivery, and use of oxytocin. Our research proves that the POU5F1 gene expression in mesenchymal stem cells decreases with each subsequent pregnancy and delivery. Wharton's jelly stem cells obtained from younger women and during their first delivery, as well as patients treated with oxytocin, show higher POU5F1 gene expression when compared with the subsequent deliveries. This leads to a conclusion that they are characterized by a lower level of differentiation, which in turn results in their greater plasticity and greater proliferative potential. Probably, they are also clinically more useful.

Antagonistic Effect of Oxytocin and Tacrolimus Combination on Adipose Tissue - Derived Mesenchymal Stem Cells: Antagonistic effect of oxytocin and tacrolimus

Tacrolimus (FK506) is a chemotherapeutic agent, which uses calcineurin pathway via inhibiting the stimulation of T cells to prevent the formation of immune response in the recipient individual in organ transplants. FK506 is mainly metabolized in the liver by cytochrome P450 enzyme system and is known that it has high toxic effects on different cells. Mesenchymal stem cells (MSCs) have recently gained importance since their potential to be used in cellular therapy and tissue regeneration. In some clinical cases, MSCs are transferred into the patient after the organ transplantations in order to support the treatment. Because of their immunomodulatory actions and assistance to the regeneration, popularity of MSCs have been increasing recently. However, since immunosuppressive agents have a potential cytotoxic and apoptotic effect on MSCs, researches have attempted to use it as a combination with an agent that alleviates these effects. Oxytocin (OT) is primarily acting as a neuromodulator in humans and is a peptide hormone secreted by the pituitary gland of the neurohypophysis. OT has such effects on cells as to confer resistance against oxidative stress on cells and to increase the proliferation and help regeneration. Studies on the active substance of FK506 were aimed to investigate the cytotoxic effects on human adipose tissue derived MSCs. The purpose of this study was to determine the cytotoxic, apoptotic and morphological effects of FK506, an immunosuppressive agent, on adipose tissue - derived MSC (ADMSC) which has the potential to be used for immune suppression. In addition, it was aimed to determine whether the agent could reduce the cytotoxic, apoptotic, and morphological effects on ADMSCs when used in combination with OT. For this purpose, the cytotoxic effects of the FK506 and OT on ADMSCs were determined by time and dose dependent manner by the WST-1 test. Isobologram analysis was evaluated using the WST-1 test according to IC₅₀ values of FK506 and OT. The apoptotic effects of the agents on the ADMSCs were determined by the Annexin V method. Immunofluorescence staining was performed to determine morphological changes. Changes in the levels of oxidative stress markers were measured by colorimetric and flourometric methods using lipid peroxidation, superoxide dismutase activity, catalase activity and glutathione peroxidase assays. The IC₅₀ values of FK506 and OT on ADMSCs were calculated as 17.44μM and 13.43μM, respectively.FK506 and OT were found to have antagonistic activity on ADMSCs (CI value of the combination was 1.24). The effects of the agents individually and in combination on the levels of apoptosis and oxidative stress markers have been evaluated. When the results obtained from the study are evaluated, the adipose- tissue derived mesenchymal stem cells used with takrolimus and oxytocin combination have a potential for novel treatment approaches.