Studies on the Effects of Nutritional Mineral Elements Zinc and Germanium on Human Monocytic Cell Line U937

• Main Authors: Yi-Wen Li, 李怡玟
• Other Authors: Kee-Lung Chang
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/80146103369117298183

碩士 === 高雄醫學大學 === 生物化學研究所 === 99 === Zinc and germanium both are essential trace elements of human and with the functions of wound repair, and immune regulation and of analgesia and anti-tumor respectively. However, it has reported that extensive intake of trace elements would cause body damage. Up to now, there isn’t evidence to demonstrate what the dosage of zinc and germanium is to affect physiological functions and how it works. Therefore, this study was designed to explore the effects of zinc or germanium on the human monocytic cell line U937. Results showed zinc at the concentrations of 10-20 μM could promote U937 cells’ proliferation and increase their phagocytic ability. Moreover, we also showed the increase of phagocytosis by zinc was through the activation of MAPK pathway-mediated MEK 2, c-jun, c-fos and NF-κB gene expression accompanied by up-regulation of the cytokines of TNF-α and IL-8. In contract, the dose higher than 1000 μM of germanium would inhibit U937 cells’ growth, cause DNA fragmentation and increase the percentage of sub G1 phase of cell cycle phases suggesting germanium induce cell death via apoptosis. At the same time, the production of reaction oxygen species dissipation of mitochondrial membrane potential ( ΔΨm ) were increased. These results indicated that zinc at physiological concentrations can enhance immunity, while extensive dose of germanium cause immune cell death. Conclusively, supplement of proper dosage of trace elements is important for health.