Abstract
Pituitary adenylate cyclase-activating polypeptide (PACAP) is a structurally endogenous peptide with many biological roles. Maxadilan, a 61-amino acid vasodilatory peptide, specifically activates the PACAP type I receptor (PAC1). Although PAC1 has been identified in embryonic stem cells, little is known about its presence or effects in human induced pluripotent stem (iPS) cells. In the present study, we investigated the expression of PAC1 in human iPS cells by reverse transcriptase polymerase chain reaction (RT-PCR) and western blot analysis. To study the physiological effects mediated by PAC1, we evaluated the role of maxadilan in preventing apoptotic cell death induced by ultraviolet C (UVC). After exposure to UVC, the iPS cells showed a marked reduction in cell viability and a parallel increase of apoptotic cells, as demonstrated by WST-8 analysis, annexin V/propidium iodide (PI) analysis and the terminal transferase dUTP nick end labeling (TUNEL) assay. The addition of 30 nM of maxadilan dramatically increased iPS cell viability and reduced the percentage of apoptotic cells. The anti-apoptotic effects of maxadilan were correlated to the downregulation of caspase-3 and caspase-9. Concomitantly, immunofluorescence, western blot analysis, real-time quantitative polymerase chain reaction (RT-qPCR) analysis and in vitro differentiation results showed that maxadilan did not affect the pluripotent state of iPS cells. Moreover, karyotype analysis showed that maxadilan did not affect the karyotype of iPS cells. In summary, these results demonstrate that PAC1 is present in iPS cells and that maxadilan effectively protects iPS cells against UVC-induced apoptotic cell death while not affecting the pluripotent state or karyotype.
Highlights
Traditional stem cell therapies face various impediments, including the ethical and immunological challenges to clinical application
Test of induced pluripotent stem (iPS) cell viability after ultraviolet C (UVC) irradiation Maxadilan markedly affected cell survival after UVC irradiation (Figure 2). iPS cells that were exposed to 50 J/m2, 75 J/m2 and 100 J/m2 UVC and treated with 30 nM maxadilan showed a significant increase in cell viability compared with iPS cells that were not treated with maxadilan. iPS cells that were irradiated with 50 J/m2, 75 J/m2 and 100 J/m2 UVC showed a 64.63%, 67.23% and 70.8% reduction in cell viability, respectively, compared with the control group
The addition of 30 nM maxadilan resulted in a 51.75%, 53.1% and 52.43% decrease in cell viability, respectively, compared with the control group. iPS cells exposed to 100 J/m2 UVC and treated with 50 nM of maxadilan showed a significant increase in cell viability compared with iPS cells that were not treated with maxadilan
Summary
Traditional stem cell therapies face various impediments, including the ethical and immunological challenges to clinical application. Through the retrovirus-mediated transfection of four transcription factors (Oct, SOX2, c-Myc, and Klf-4), they successfully reprogrammed murine fibroblasts into a state that was similar to an embryonic stem cell [1], a type of reprogrammed cell termed an induced pluripotent stem (iPS) cell. These iPS cells were difficult to distinguish from embryonic stem (ES) cells in morphology, proliferative abilities, surface antigens, gene expression, epigenetic status of pluripotent cell-specific genes and telomerase activity [2]. The identification of an anti-apoptotic drug that can effectively prevent apoptosis in the iPS cell culture medium will be important for generating iPS cells at a scale that can accommodate future clinical applications
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
