Chinese Journal of Tissue Engineering Research ›› 2020, Vol. 24 ›› Issue (31): 4954-4960.doi: 10.3969/j.issn.2095-4344.2147

Previous Articles     Next Articles

Relationship between mitochondrial autophagy and chondrogenesis of bone marrow mesenchymal stem cells

Li Yuanqi1, 2, Lin Hai2, Luo Hongrong2, Zhang Xingdong1, 2   

  1. 1Guangxi Collaborative Innovation Center for Biomedicine, Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, China; 2Engineering Research Center in Biomaterials, Sichuan University, Chengdu 610064, Sichuan Province, China

  • Received:2020-04-16 Revised:2020-04-20 Accepted:2020-05-09 Online:2020-11-08 Published:2020-09-03
  • Contact: Zhang Xingdong, MD, Professor, Guangxi Collaborative Innovation Center for Biomedicine, Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, China; Engineering Research Center in Biomaterials, Sichuan University, Chengdu 610064, Sichuan Province, China Lin Hai, MD, Associate researcher, Engineering Research Center in Biomaterials, Sichuan University, Chengdu 610064, Sichuan Province, China
  • About author:Li Yuanqi, Master candidate, Guangxi Collaborative Innovation Center for Biomedicine, Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, China; Engineering Research Center in Biomaterials, Sichuan University, Chengdu 610064, Sichuan Province, China
  • Supported by:
    the National Key Research and Development Program of China during the 13th Five-Year Plan Period, No. 2018YFC1106203 ; the Key Science and Technology Program of Guangxi Zhuang Autonomous Region, No. Guike AA17204085-2 

Abstract:

BACKGROUND: It has been found that mitochondrial autophagy plays an important role in cartilage defect repair. Therefore, it is necessary to study the influence and regulatory method of mitochondrial autophagy on the chondrogenesis of bone marrow mesenchymal stem cells, which will lay a foundation for further elucidating the cartilage-inducing mechanism and understanding how biomaterials regulate the differentiation and fate of bone marrow mesenchymal stem cells.

OBJECTIVE: To establish and verify characterization methods of mitochondrial status and degree of autophagy, to observe the relationship of mitochondrial autophagy with chondrocyte development and the differentiation of bone marrow mesenchymal stem cells into cartilage.

METHODS: Chondrocytes from neonatal neonates, 1-month-old rabbits, 18-month-old rabbits and neonatal neonatal rabbit bone marrow mesenchymal stem cells were separated and cultured. According to the instructions in the kit, Mito Tracker Red staining was conducted. The second-generation bone marrow mesenchymal stem cells were selected, and cultured with complete cartilage induction medium. Mitochondrial marker Mito Tracker Red staining was performed on days 1, 3, and 7 according to the kit instructions. The bone marrow mesenchymal stem cells of passage 2 were selected and cultured with complete cartilage induction medium for 24 hours. The induction group was added with 10 μmol/L autophagy inducer rapamycin for 10 hours, and the inhibition group was added with 5 μmol/L autophagy inhibitor chloroquine for 10 hours. After that, it was replaced with complete cartilage culture medium, and stained with mitochondrial autophagy kit Mitophagy Detection Kit on days 1, 3, and 7 to observe the situation of mitochondrial autophagy.

RESULTS AND CONCLUSION: (1) Mitochondrial staining of chondrocytes from rabbits at different ages: The mitochondrial number in chondrocytes from young rabbits was higher than that from old rabbits. (2) Mitochondrial staining of bone marrow mesenchymal stem cells and newborn rabbit chondrocytes: The mitochondrial morphology in chondrocytes was spot dispersion, while that in bone marrow mesenchymal stem cells was linear distribution. (3) Mitochondrial staining during bone marrow mesenchymal stem cells differentiation: With the increase of induction culture time, the mitochondrial morphology in stem cells changed from the tubular network structure to a spotted situation, and the microfilament structure which promotes the formation of autophagy gradually decreases during the bone marrow mesenchymal stem cells differentiation. (4) The effect of mitochondrial autophagy on chondrogenic differentiation of bone marrow mesenchymal stem cells: Rapamycin promotes the mitochondrial autophagy pathway, and further promotes the chondrogenic differentiation of bone marrow mesenchymal stem cells.  

Key words: stem cells,  bone marrow mesenchymal stem cells,  chondrocytes,  mitochondria,  autophagy,  rapamycin,  chloroquine,  experiment

CLC Number: