Effect of fluoride ion on proliferation of Vero cell line cells: growth acceleration by sodium fluoride.

Abstract

The effect of fluoride ion (NaF) on proliferation was examined in Vero cells derived from kidney tissue of Cercopithecus aethiops. Fluoride ion concentrations in the growth medium of 0.1, 1, 10, and 100 ppm were employed in the first experiment and of 0.1, 0.2, 0.5, 1, 2, 5, 10, 20, 50, and 100 ppm in the second. Simplified replicate cultures were prepared and cultivated for about five days. After cultivation, cell growth was estimated by enumerating cell nuclei concentration. A relationship between cell proliferation and fluoride concentrations in the growth medium was confirmed statistically and details from control and experimental cell growth were investigated. Cell growth was accelerated by 17-18% with increasing fluoride ion concentrations of 1-10 ppm in first experiment. Maximum proliferation occurred at 2 ppm in the second experiment with a 22.6% rate of increase. Thereafter cell growth was reduced with increasing fluoride ion concentrations until near 100 ppm, at which concentration cell growth was completely stopped in both experiments. Introduction The relationship between cell proliferation and fluoride concentrations in growth medium has been studied by many investigators. In these studies here we have examined the proliferative potency and cellular metabolic alteration accompanying changes in fluoride concentrations. In 1960, Pace and Elrod, in their papers on effects of respiratory inhibitors, reported that 10-3M sodium fluoride (ca. 19 ppm F-) decreased L cell growth by 24%1). Berry and Trillwood reported in 1963 that 0.1-10.0 mg/l NaF (ca. 0.045-4.5 ppm F-) appreciably ca. 15-35%) depressed HeLa S-3 oxf and mouse fibroblast L (clone 12/oxf) cell growth2).However Albright and Armstrong et al. questioned these results. Then, Albright reported in 1964 that examining murine leukemic lymphoblasts, L5178Y strain, 3x 10-4M (5-6 ppm) Fdid not produce significant growth inhibition, and he also suggested that 4.4X 10-4 M (8-9 ppm) Fmight indicate incipient growth depressions). Armstrong et al. reported in 1965 that 10 ppm fluoride had no effect on HeLa and Minn. EE cell multiplication. But Berry and Trillwood responded that Armstrong et al. failed to get significant cell growth5). Against this criticism, Armstrong et al.immediately stated that 10 ppm Fdid not cause growth inhibition under satisfactory conditions6).Nias, who provided HeLa and L cells to Berry and Trillwood, concluded the arguments with his observation that 1 ppm NaF did not inhibit HeLa cell growth under experimental conditions similar to those of 55 * Department of Preventive Dentistry , Niigata University school of Dentistry(Director: Professor Kin-ichi HORII) *新 潟 大学歯学部予防歯科学教室(主 任:堀 井欣一教授) 昭和 56 年 8 月 12 日受付