Title Page
Contents
ABSTRACT 12
Ⅰ. INTRODUCTION 15
Ⅱ. LITERATURE REVIEW 19
1. FOLFIRI-induced muscle atrophy 19
1) The chemotherapeutic effect of FOLFIRI 19
2) Mitochondrial dysfunction induced by FOLFIRI 25
3) The molecular mechanisms of the chemotherapy-induced muscle atrophy 29
2. Therapeutic strategies for alleviating FOLFIRI-induced muscle atrophy 34
1) Mitochondrial targeted drug therapy against muscle atrophy 34
2) Nutritional approaches 35
3. Characteristics of Camellia japonica 37
1) General features of Camellia 37
2) Biological properties of Camellia japonica 37
4. Aims of the study 41
Ⅲ. Materials and Methods 44
1. Preparation of CJT 44
2. Cell culture and treatment 44
3. Imunofluorescence staining 45
4. Western blot 45
5. Mitochondrial mass 46
6. ADP/ATP assay 47
7. Mitochondrial ROS production 47
8. Mitochondrial membrane potential 47
9. Zebrafish maintenance and experimental protocols 48
10. Whole mount immunostaining and measurement of muscle fiber width 48
11. Confocal live imaging and measurement of EGFP and mitochondrial length 49
12. Real-time quantitative polymerase chain reaction (RT-qPCR) 49
13. Statistical analysis 53
Ⅳ. RESULTS 54
1. Effects of CJT on muscle differentiation and mitochondrial function 54
1) CJT stimulates myogenesis and elevates muscle protein synthesis in C2C12 cells 54
2) CJT improves mitochondrial content and mitochondrial function in C2C12 cells 59
2. Effects of CJT on FOLFIRI-induced muscle atrophy in C2C12 myotubes and zebrafish embryos 65
1) CJT attenuates FOLFIRI-induced myotube atrophy by inhibiting muscle proteolytic system in C2C12 myotubes 65
2) CJT alleviates FOLFIRI-induced mitochondrial depletion in C2C12 myotubes 71
3) CJT inhibits FOLFIRI-induced mitochondrial dysfunction in C2C12 myotubes 75
4) CJT mitigates muscle atrophy and mitochondrial damage induced by FOLFIRI in zebrafish embryos 81
Ⅴ. DISCUSSION 87
Ⅵ. SUMMARY AND CONCLUSION 95
Ⅶ. REFERENCES 100
ABSTRACT IN KOREAN 113
Table 1. Oligonucleotide primer sequences used for the RT-qPCR analysis 51
Figure 1. Mechanism of action of FOLFIRI 24
Figure 2. The hypothesis of the study 42
Figure 3. Overall experimental scheme 43
Figure 4. CJT promotes mature multinucleated myotube formation in C2C12 cells. 56
Figure 5. CJT stimulates myoblast differentiation in C2C12 cells. 57
Figure 6. CJT elevates muscle protein synthesis by increasing PI3K/Akt/mTOR/p70S6K pathway in C2C12 cells. 58
Figure 7. CJT elevates mitochondrial biogenesis in C2C12 cells. 61
Figure 8. CTJ improves mitochondrial dynamics in C2C12 cells. 62
Figure 9. CJT increases mitochondrial mass in C2C12 cells. 63
Figure 10. CJT stimulates mitochondrial oxidative phosphorylation in C2C12 cells. 64
Figure 11. CJT protects myotubes against myotube atrophy in FOLFIRI-treatedC2C12 myotubes. 67
Figure 12. CJT prevents inhibition of MHC protein expression in FOLFIRI-treated C2C12 myotubes. 68
Figure 13. CJT alleviates the protein expression of muscle specific E3 ligases by inhibiting FoxO1 and NFκB pathway in FOLFIRI-... 69
Figure 14. CJT inhibits the autophagy progression in FOLFIRI-treated C2C12 myotubes. 70
Figure 15. CJT restored the FOLFIRI-induced mitochondrial depletion in FOLFIRI-treated C2C12 myotubes 72
Figure 16. CJT mitigates the mitochondrial biogenesis in FOLFIRI-treated C2C12 myotubes. 73
Figure 17. CJT improves an imbalance in mitochondrial dynamics in FOLFIRI-treated C2C12 myotubes. 74
Figure 18. CJT restored mitochondrial oxidative phosphorylation in FOLFIRI-treated C2C12 myotubes. 76
Figure 19. CJT impedes the reduction of ATP levels in FOLFIRI-treated C2C12 myotubes. 77
Figure 20. CJT prevents myotubes against a decrease in mitochondrial membrane potential in FOLFIRI-induced C2C12 myotubes. 78
Figure 21. CJT alleviates an increase in the production of mitochondrial ROS production in FOLFIRI-induced C2C12 myotubes. 79
Figure 22. CJT inhibits apoptosis by reducing AMPK activation in FOLFIRI-treated C2C12 myotubes. 80
Figure 23. CJT protects myofibers from muscle atrophy in FOLFIRI-treated zebrafish embryos. 83
Figure 24. CJT increases the mitochondrial mass and the mitochondrial length in FOLFIRI-treated Tg(mito:EGFP) zebrafish embryos. 84
Figure 25. CJT increases slow- and fast-twitch myofibers in FOLFIRI-treated zebrafish embryos. 85
Figure 26. CJT prevents myofibers against altered mitochondrial function in FOLFIRI-treated zebrafish embryos. 86
Figure 27. Summary of the effects of CJT on muscle hypertrophy. 98
Figure 28. Summary of the effects of CJT on FOLFIRI-induced muscle atrophy. 99