Transfer of mitochondria from mesenchymal stem cells derived from induced pluripotent stem cells attenuates hypoxia-ischemia-induced mitochondrial dysfunction in PC12 cells

Yan Yang; Gen Ye; Yue-Lin Zhang; Hai-Wei He; Bao-Qi Yu; Yi-Mei Hong; Wei You; Xin Li

doi:10.4103/1673-5374.266058

Transfer of mitochondria from mesenchymal stem cells derived from induced pluripotent stem cells attenuates hypoxia-ischemia-induced mitochondrial dysfunction in PC12 cells

Neural Regen Res. 2020 Mar;15(3):464-472. doi: 10.4103/1673-5374.266058.

Authors

Yan Yang¹, Gen Ye², Yue-Lin Zhang³, Hai-Wei He³, Bao-Qi Yu⁴, Yi-Mei Hong³, Wei You³, Xin Li³

Affiliations

¹ Department of Emergency Medicine, Department of Emergency and Critical Care Medicine, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences; Department of Emergency, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China.
² Department of Emergency Medicine, Department of Emergency and Critical Care Medicine, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou; Shantou University Medical College, Shantou, Guangdong Province, China.
³ Department of Emergency Medicine, Department of Emergency and Critical Care Medicine, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong Province, China.
⁴ Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Key Laboratory of Remodelling-related Cardiovascular Diseases, Ministry of Education, Beijing, China.

Abstract

Mitochondrial dysfunction in neurons has been implicated in hypoxia-ischemia-induced brain injury. Although mesenchymal stem cell therapy has emerged as a novel treatment for this pathology, the mechanisms are not fully understood. To address this issue, we first co-cultured 1.5 × 10⁵ PC12 cells with mesenchymal stem cells that were derived from induced pluripotent stem cells at a ratio of 1:1, and then intervened with cobalt chloride (CoCl₂) for 24 hours. Reactive oxygen species in PC12 cells was measured by Mito-sox. Mitochondrial membrane potential (?Ψm) in PC12 cells was determined by JC-1 staining. Apoptosis of PC12 cells was detected by terminal deoxynucleotidal transferase-mediated dUTP nick end-labeling staining. Mitochondrial morphology in PC12 cells was examined by transmission electron microscopy. Transfer of mitochondria from the mesenchymal stem cells derived from induced pluripotent stem cells to damaged PC12 cells was measured by flow cytometry. Mesenchymal stem cells were induced from pluripotent stem cells by lentivirus infection containing green fluorescent protein in mitochondria. Then they were co-cultured with PC12 cells in Transwell chambers and treated with CoCl₂ for 24 hours to detect adenosine triphosphate level in PC12 cells. CoCl₂-induced PC12 cell damage was dose-dependent. Co-culture with mesenchymal stem cells significantly reduced apoptosis and restored ?Ψm in the injured PC12 cells under CoCl₂ challenge. Co-culture with mesenchymal stem cells ameliorated mitochondrial swelling, the disappearance of cristae, and chromatin margination in the injured PC12 cells. After direct co-culture, mitochondrial transfer from the mesenchymal stem cells stem cells to PC12 cells was detected via formed tunneling nanotubes between these two types of cells. The transfer efficiency was greatly enhanced in the presence of CoCl₂. More importantly, inhibition of tunneling nanotubes partially abrogated the beneficial effects of mesenchymal stem cells on CoCl₂-induced PC12 cell injury. Mesenchymal stem cells reduced CoCl₂-induced PC12 cell injury and these effects were in part due to efficacious mitochondrial transfer.

Keywords: PC12 cells; apoptosis; brain injury; hypoxia-ischemia; induced pluripotent stem cells; mesenchymal stem cells; mitochondrial membrane potential; mitochondrial transfer; tunneling nanotubes.