Effect of Celecoxib on Ca²⁺Fluxes and Proliferation in MDCK Renal Tubular Cells

Abstract

The effect of celecoxib on renal tubular cells is largely unexplored. In Madin Darby canine kidney (MDCK) cells, the effect of celecoxib on intracellular CaCa2+ concentration ([Ca2+]i) and proliferation was examined by using the Ca(2 +)-sensitive fluorescent dye fura-2 and the viability detecting fluorescent dye tetrazolium, respectively. Celecoxib (> or =1 micro M) caused an increase of [CaCa2+]i in a concentration-dependent manner. Celecoxib-induced [CaCa2+]i increase was partly reduced by removal of extracellular CaCa2+. Celecoxib-induced CaCa2+ influx was independently suggested by MnCa2+ influx-induced fura-2 fluorescence quench. In Ca(2 +)-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca(2 +)-ATPase, caused a monophasic [CaCa2+]i increase, after which celecoxib only induced a tiny [CaCa2+]i increase; conversely, pretreatment with celecoxib completely inhibited thapsigargin-induced [CaCa2+]i increases. U73122, an inhibitor of phospholipase C, abolished ATP (but not celecoxib)-induced [CaCa2+]i increases. Overnight incubation with 1 or 10 micro M celecoxib decreased cell viability by 80% and 100%, respectively. These data indicate that celecoxib evokes a [CaCa2+]i increase in renal tubular cells by stimulating both extracellular CaCa2+ influx and intracellular CaCa2+ release and is highly toxic to renal tubular cells in vitro.

Effect of Methoxychlor on Ca2+ Movement and Viability in MDCK Renal Tubular Cells

“…The intracellular Ca 2+ store involved in methoxychlor‐induced [Ca 2+ ] i rise was explored. Previous studies have shown that the endoplasmic reticulum is the major Ca 2+ store in MDCK cells . Figure A shows that in Ca 2+ ‐free medium, addition of 20 μM methoxychlor induced a [Ca 2+ ] i rise of 35 ± 2 nM (n = 3).…”

“…The MDCK cell line is a useful model for renal research. It has been shown that in this cell type, several ligands can cause a [Ca 2+ ] i rise, such as sulforaphane , anandamide , celecoxib , and endogenous ligands like ATP and bradykinin , via causing Ca 2+ entry and Ca 2+ release.…”

Effect of capsaicin on Ca2+ fluxes in Madin‐Darby canine renal tubular cells

“…Ca 21 signaling plays a crucial role in the function of almost all cell types including MDCK renal tubular cells [Jan et al, 1998[Jan et al, , 2000Wang et al, 2005;Yeh et al, 2006;Liu et al, 2008]. A change in [Ca 21 ] i in renal tubular cells may affect many functions including cell volume regulation and transport [Vallon, 2008].…”

“…Experiments were performed to explore the Ca 21 entry pathway of the capsaicin-induced response. Three store-operated Ca 21 influx inhibitors, nifedipine, econczole, and SKF96365 [Harper et al, 2003;Ishikawa et al, 2003;Jiang et al, 2006;Quinn et al, 2004], the protein kinase C activator, phorbol Previous reports have shown that the endoplasmic reticulum is the major Ca 21 store in MDCK cells [Jan et al, 1998[Jan et al, , 2000Wang et al, 2005;Yeh et al, 2006;Liu et al, 2008]. Thapsigargin, an inhibitor of endoplasmic reticulum Ca 21 pumps [Thastrup et al, 1990], was used to deplete endoplasmic reticulum Ca 21 stores to see whether capsaicin utilized this store to cause intracellular Ca 21 release.…”

Effect of capsazepine on [Ca2+]i in MDCK renal tubular cells

“…The Madin Darby canine kidney (MDCK) (renal tubular) cell line is a useful model for renal research. It has been shown in this cell line that [Ca 2+ ] i increases in response to stimulation via exogenous ligands such as melittin [Liu et al, 2008], anandamide [Yeh et al, 2006], celecoxib [Wang et al, 2005], and endogenous ligands like ATP [Huang and Jan, 2001] and bradykinin [Jan et al, 2000]. In the present study, using fura‐2 as a fluorescent Ca 2+ ‐sensitive dye, we show that capsazepine induces concentration‐dependent [Ca 2+ ] i increases both in the presence and absence of extracellular Ca 2+ in MDCK cells.…”