ABSTRACT
Carvacrol, a monoterpenic phenol compound, has been shown to possess various biological effects in different models. However, the effect of carvacrol on intracellular Ca²âº and its related physiology in human prostate cancer is unknown. This study explored the effect of carvacrol on cytosolic free Ca²âº levels ([Ca²âº]i) and viability in PC3 human prostate cancer cells. Fura-2, a Ca²âº- sensitive fluorescent dye, was used to assess [Ca²âº]i. Cell viability was measured by the detecting reagent WST-1. Carvacrol at concentrations of 200-800 µM caused [Ca²âº]i rises in a concentration-dependent manner. Removal of extracellular Ca²âº reduced carvacrol's effect by approximately 60%. Carvacrol-induced Ca²âº entry was confirmed by Mn²âº entry-induced quench of fura-2 fluorescence, and was inhibited by approximately 30% by nifedipine, econazole, SKF96365, and the protein kinase C (PKC) inhibitor GF109203X. In Ca²âº-free medium, treatment with the endoplasmic reticulum Ca²âº pump inhibitor thapsigargin (TG) abolished carvacrol-induced [Ca²âº]i rises. Treatment with carvacrol also abolished TG-induced [Ca²âº]i rises. Carvacrol-induced Ca²âº release from the endoplasmic reticulum was abolished by inhibition of phospholipase C (PLC). Carvacrol killed cells at concentrations of 200-600 µM in a concentration-dependent fashion. Chelating cytosolic Ca²âº with BAPTA/AM did not prevent carvacrol's cytotoxicity. Together, in PC3 cells, carvacrol induced [Ca²âº]i rises by inducing PLC-dependent Ca²âº release from the endoplasmic reticulum and Ca²âº entry via PKC-sensitive store-operated Ca²âº channels and other unknown channels. Carvacrol also induced Ca²âº-dissociated cell death.
Subject(s)
Calcium/metabolism , Monoterpenes/pharmacology , Prostatic Neoplasms/drug therapy , Cell Line, Tumor , Cell Survival/drug effects , Cymenes , Humans , Male , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Type C Phospholipases/physiologyABSTRACT
Safrole is a carcinogen found in plants. The effect of safrole on cytosolic free Ca²âº concentrations ([Ca²âº](i)) and viability in SCM1 human gastric cancer cells was explored. The Ca²âº-sensitive fluorescent dye fura-2 was applied to measure [Ca²âº](i). Safrole at concentrations of 150-450 µM induced a [Ca²âº](i) rise in a concentration-dependent manner. The response was reduced by 60% by removing extracellular Ca²âº. Safrole-evoked Ca²âº entry was not altered by nifedipine, econazole, SKF96365, and protein kinase C activator or inhibitor. In Ca²âº-free medium, treatment with the endoplasmic reticulum Ca²âº pump inhibitor thapsigargin or 2,5-di-tert-butylhydroquinone (BHQ) abolished safrole-evoked [Ca²âº](i) rises. Conversely, treatment with safrole abolished thapsigargin or BHQ-evoked [Ca²âº](i) rises. Inhibition of phospholipase C (PLC) with U73122 abolished safrole-induced [Ca²âº](i) rises. At 250-550 µM, safrole decreased cell viability concentration-dependently, which was not reversed by chelating cytosolic Ca²âº with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid/acetoxy methyl (BAPTA/AM). Annexin V/propidium iodide staining data suggest that safrole (350-550 µM) induced apoptosis concentration-dependently. These studies suggest that in SCM1 human gastric cancer cells, safrole induced [Ca²âº](i) rises by inducing PLC-dependent Ca²âº release from the endoplasmic reticulum and Ca²âº influx via non-store-operated Ca²âº entry pathways. Safrole-induced cell death may involve apoptosis.
Subject(s)
Apoptosis/drug effects , Calcium/metabolism , Safrole/adverse effects , Stomach/drug effects , Cell Death , Cell Line, Tumor , Fura-2 , Humans , Type C Phospholipases/metabolismABSTRACT
Protriptyline, a tricyclic anti-depressant, is used primarily to treat the combination of symptoms of anxiety and depression. However, the effect of protriptyline on prostate caner is unknown. This study examined whether the anti-depressant protriptyline altered Ca(2+) movement and cell viability in PC3 human prostate cancer cells. The Ca(2+)-sensitive fluorescent dye fura-2 was used to measure [Ca(2+)](i). Protriptyline evoked [Ca(2+)](i) rises concentration-dependently. The response was reduced by removing extracellular Ca(2+). Protriptyline-evoked Ca(2+) entry was inhibited by store-operated channel inhibitors (nifedipine, econazole and SKF96365), protein kinase C activator (phorbol 12-myristate 13 acetate, PMA) and protein kinase C inhibitor (GF109203X). Treatment with the endoplasmic reticulum Ca(2+) pump inhibitor 2,5-di-tert-butylhydr-oquinone (BHQ) in Ca(2+)-free medium inhibited 60% of protriptyline-evoked [Ca(2+)](i) rises. Conversely, treatment with protriptyline abolished BHQ-evoked [Ca(2+)](i) rises. Inhibition of phospholipase C with U73122 suppressed 50% of protriptyline-evoked [Ca(2+)](i) rises. At concentrations of 50-70 µM, protriptyline decreased cell viability in a concentration-dependent manner; which were not reversed by chelating cytosolic Ca(2+) with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM). Collectively, in PC3 cells, protriptyline evoked [Ca(2+)](i) rises by inducing phospholipase C-associated Ca(2+) release from the endoplasmic reticulum and other stores, and Ca(2+) influx via protein kinase C-sensitive store-operated Ca(2+) channels. Protriptyline caused cell death that was independent of [Ca(2+)](i) rises.
Subject(s)
Apoptosis/drug effects , Calcium Signaling/drug effects , Calcium/metabolism , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Protriptyline/administration & dosage , Biological Transport, Active/drug effects , Cell Line, Tumor , Dose-Response Relationship, Drug , Humans , Male , Prostatic Neoplasms/drug therapyABSTRACT
The effect of sertraline, a selective serotonin reuptake inhibitor (SSRI), on cytosolic free Ca²âº concentrations ([Ca²âº](i)) in a rabbit corneal epithelial cell line (SIRC) is unclear. This study explored whether sertraline changed basal [Ca²âº](i) levels in suspended SIRC cells by using fura-2 as a Ca²âº-sensitive fluorescent dye. Sertraline at concentrations between 10-100 µM increased [Ca²âº](i) in a concentration-dependent manner. The Ca²âº signal was reduced by 23% by removing extracellular Ca²âº. Sertraline induced Mn²âº influx, leading to quench of fura-2 fluorescence, suggesting Ca²âº influx. This Ca²âº influx was inhibited by phospholipase A2 inhibitor aristolochic acid, but not by store-operated Ca²âº channel blockers and protein kinase C/A modulators. In Ca²âº-free medium, pretreatment with the endoplasmic reticulum Ca²âº pump inhibitor thapsigargin, cyclopiazonic acid or 2,5-di-tert-butylhydroquinone greatly inhibited sertraline-induced Ca²âº release. Inhibition of phospholipase C with U73122 abolished sertraline-induced [Ca²âº](i) rise. At concentrations of 5-50 µM, sertraline killed cells in a concentration-dependent manner. The cytotoxic effect of 25 µM sertraline was not reversed by prechelating cytosolic Ca²âº with BAPTA/AM. Collectively, in SIRC cells, sertraline induced [Ca²âº](i) rises by causing phospholipase C-dependent Ca²âº release from the endoplasmic reticulum and Ca²âº influx via phospholipase A2-sensitive Ca²âº channels. Sertraline-caused cytotoxicity was mediated by Ca²âº-independent pathways.
Subject(s)
Calcium Signaling/physiology , Calcium/metabolism , Epithelial Cells/metabolism , Epithelium, Corneal/cytology , Epithelium, Corneal/metabolism , Sertraline/administration & dosage , Animals , Calcium Signaling/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Epithelial Cells/drug effects , Epithelium, Corneal/drug effects , Rabbits , Selective Serotonin Reuptake Inhibitors/administration & dosageABSTRACT
Melamine is thought to be an endocrine disrupter that affects physiology in cells. This study examined the effect of melamine on cytosolic free Ca(2+) concentrations ([Ca(2+)]i) and viability in PC3 human prostate cancer cells. Melamine evoked [Ca(2+)]i rises concentration-dependently. Melamine-evoked Ca(2+) entry was inhibited by nifedipine, econazole, SKF96365, GF109203X and phorbol 12-myristate 13 acetate. In Ca(2+)-free medium, treatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin inhibited melamine-evoked [Ca(2+)]i rise. Conversely, treatment with melamine abolished thapsigargin-evoked [Ca(2+)]i rise. Inhibition of phospholipase C with U73122 did not alter melamine-evoked [Ca(2+)]i rise. Melamine at 500-800µM decreased cell viability, which was not reversed by pretreatment with the Ca(2+) chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM). Collectively, our data suggest that in PC3 cells, melamine induced [Ca(2+)]i rises by evoking phospholipase C-independent Ca(2+) release from the endoplasmic reticulum, and Ca(2+) entry via protein kinase C-regulated store-operated Ca(2+) entry. Melamine also caused Ca(2+)-independent cell death.
