Investigating the Effect of SIRT1 Gene on Macrophages and Wound Healing

• Main Authors: Hung,Yi-Wun, 洪怡雯
• Other Authors: Shieh,Yi-Shing
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/j657fz

碩士 === 國防醫學院 === 生物化學研究所 === 107 === Background. Chronic wound problems plague many people, and it is a major clinical and economic problem for older people to avoid wound healing. Macrophages are thought to play a critical regulatory role in many stages of wound healing, including angiogenesis, re-epithelialization, and remodeling. SIRT1 is a key regulator of macrophage self-renewal that integrates cell cycle and longevity pathways. Studies have also shown that SIRT1 can speed up angiogenesis and re-epithelialization. Aim. To investigate the role of SIRT1 in macrophage polarization and in promoting wound healing. Method. Human monocyte cell line THP-1 was used for macrophage induction by addition of PMA for 24 hours. Knockdown SIRT1 in macrophages was performed by small interference RNA (si-RNA). Condition medium (CM) from control si-SIRT1 and macrophage were collected and used to treat human immortalized keratinocyte HaCaT cell. M1/M2 cytokines expression in control and SIRT1 knockdown macrophage were measured by RT-PCR, QPCR and ELISA. Function change in control and si-SIRT1 macrophages were investigated by phagocytosis. The effect of CM on epithelial migration was examined by wound healing assay. Result. The amount of M1-related cytokines in the SIRT1 knockdown macrophages of was higher than that in the control group, whereas M2 cytokines were lower than the control group which indicated macrophages polarize toward the M1 phenotype. The vascular endothelial growth factor (VEGF) expression was lower than of the control group. Moreover, macrophages with si-SIRT1 knockdown that favored the M1 phenotype were also less able to phagocytosis than control cells. The migration rate of HaCaT cells decreased in treating with CM from macrophages with si-SIRT1 as compared to control group. Conclusion. To sum up, these results in our experiment demonstrated the potential effect SIRT1 on the function and polarization of macrophages. In addition, SIRT1 is potentially involved in accelerating wound healing.