Abstract:

BACKGROUND: A certain concentration of strontium is beneficial for the human body. Strontium can affect the proliferation and enzyme activity of a variety of cells in the human body.
OBJECTIVE: To investigate the effects of strontium mineral waters with different concentrations on the proliferation and Na+-K+-adenosine-triphosphatase (Na+-K+-ATPase) activity of human renal tubular epithelial cells (HK-2 cells).
METHODS: Human renal tubular epithelial cells were cultured in vitro. After cultured in a normal Dulbecco’s Modified Eagle’s Medium (high glucose) for 24 hours, the cells were cultured in the conditioned medium containing 2, 4, 6, 8 mg/L strontium mineral waters and double distilled water. The proliferation of HK-2 cells was observed by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide (MTT) assay at hours 48, 72, 96 and 110. The Na+-K+-ATPase activity of the cells cultured for 110 hours was judged by measuring the amount of inorganic phosphorus.
RESULTS AND CONCLUSION: The results of MTT showed that 2 mg/L strontium mineral water could not affect the proliferation of HK-2 cells. When the cells were cultured for 110 hours, the cells in the double distilled water group were found growth inhibition, while the proliferation of the cells in the 6, 8, 10 mg/L strontium mineral water groups could still keep vigorous (P < 0.05). Moreover, the cell growth cycle was prolonged in the 6, 8, 10 mg/L strontium mineral water groups, especially in the 4 mg/L strontium mineral water group (P < 0.05). Compared with the double distilled water group, the Na+-K+-ATPase activity of strontium mineral waters groups was higher in the strontium mineral water groups (P < 0.05), especially in the 6 mg/L strontium mineral water group (P < 0.05). These findings suggest that the strontium mineral water with higher concentration can prolong proliferation cycle of renal tubular cells and promote the transport function of renal tubular cells.