The carcinogen safrole increases intracellular free Ca2+ levels and causes death in MDCK cells.

@article{citeulike:1475367, abstract = {The effect of the carcinogen safrole on intracellular Ca2+ movement in renal tubular cells has not been explored previously. The present study examined whether safrole could alter Ca2+ handling in Madin-Darby canine kidney (MDCK) cells. Cytosolic free Ca2+ levels ([Ca2+]i) in populations of cells were measured using fura-2 as a fluorescent Ca2+ probe. Safrole at concentrations above 33 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 400 microM. The Ca2+ signal was reduced by 90\% by removing extracellular Ca2+, but was not affected by nifedipine, verapamil, or diltiazem. Addition of Ca2+ after safrole had depleted intracellular Ca(2+)-induced dramatic Ca2+ influx, suggesting that safrole caused store-operated Ca2+ entry. In Ca(2+)-free medium, after pretreatment with 650 microM safrole, 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) failed to release more Ca 2+. Inhibition of phospholipase C with 2 microM U73122 did not affect safrole-induced Ca2+ release. Trypan blue exclusion assays revealed that incubation with 650 microM safrole for 30 min did not kill cells, but killed 70\% of cells after incubation for 60 min. Collectively, the data suggest that in MDCK cells, safrole induced a [Ca2+] increase by causing Ca2+ release from the endoplasmic reticulum in a phospholipase C-independent fashion, and by inducing Ca2+ influx via store-operated Ca2+ entry. Furthermore, safrole can cause acute toxicity to MDCK cells.}, address = {Department of Surgery, Ping-Tung Christian Hospital, Ping-Tung 900, Taiwan, ROC.}, author = {Chen, W. C. and Cheng, H. H. and Huang, C. J. and Lu, Y. C. and Chen, I. S. and Liu, S. I. and Hsu, S. S. and Chang, H. T. and Huang, J. K. and Chen, J. S. and Jan, C. R. }, citeulike-article-id = {1475367}, issn = {0304-4920}, journal = {Chin J Physiol}, month = {February}, number = {1}, pages = {34--40}, posted-at = {2007-07-23 16:29:57}, priority = {2}, title = {The carcinogen safrole increases intracellular free Ca2+ levels and causes death in MDCK cells.}, url = {http://view.ncbi.nlm.nih.gov/pubmed/17593801}, volume = {50}, year = {2007} }

TY - JOUR ID - citeulike:1475367 L3 - citeulike-article-id:1475367 TI - The carcinogen safrole increases intracellular free Ca2+ levels and causes death in MDCK cells. JF - Chin J Physiol VL - 50 IS - 1 SP - 34 EP - 40 AD - Department of Surgery, Ping-Tung Christian Hospital, Ping-Tung 900, Taiwan, ROC. SN - 0304-4920 N2 - The effect of the carcinogen safrole on intracellular Ca2+ movement in renal tubular cells has not been explored previously. The present study examined whether safrole could alter Ca2+ handling in Madin-Darby canine kidney (MDCK) cells. Cytosolic free Ca2+ levels ([Ca2+]i) in populations of cells were measured using fura-2 as a fluorescent Ca2+ probe. Safrole at concentrations above 33 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 400 microM. The Ca2+ signal was reduced by 90% by removing extracellular Ca2+, but was not affected by nifedipine, verapamil, or diltiazem. Addition of Ca2+ after safrole had depleted intracellular Ca(2+)-induced dramatic Ca2+ influx, suggesting that safrole caused store-operated Ca2+ entry. In Ca(2+)-free medium, after pretreatment with 650 microM safrole, 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) failed to release more Ca 2+. Inhibition of phospholipase C with 2 microM U73122 did not affect safrole-induced Ca2+ release. Trypan blue exclusion assays revealed that incubation with 650 microM safrole for 30 min did not kill cells, but killed 70% of cells after incubation for 60 min. Collectively, the data suggest that in MDCK cells, safrole induced a [Ca2+] increase by causing Ca2+ release from the endoplasmic reticulum in a phospholipase C-independent fashion, and by inducing Ca2+ influx via store-operated Ca2+ entry. Furthermore, safrole can cause acute toxicity to MDCK cells. AU - Chen, WC AU - Cheng, HH AU - Huang, CJ AU - Lu, YC AU - Chen, IS AU - Liu, SI AU - Hsu, SS AU - Chang, HT AU - Huang, JK AU - Chen, JS AU - Jan, CR PY - 2007/02/28/ UR - http://view.ncbi.nlm.nih.gov/pubmed/17593801 ER -