1.NPC-14686, a novel anti-inflammatory agent, increased intracellular Ca(2+) concentrations in MDCK renal tubular cells.
Jan CR1, Wang JL, Chou KJ, Cheng JS, Lee KC, Tseng LL, Wang SP, Tang KY, Huang JK. Int J Immunopharmacol. 2000 Nov;22(11):915-21.
The effect of NPC-14686 (Fmoc-L-homophenylalanine), a novel anti-inflammatory agent on intracellular free Ca(2+) concentrations ([Ca(2+)](i)) in Madin Darby canine kidney (MDCK) renal tubular cells, was investigated, using fura-2 as a Ca(2+) dye. At concentrations between 10 and 200 microM NPC-14686 increased [Ca(2+)](i) concentration dependently. The [Ca(2+)](i) signal comprised an initial rise and a sustained phase. Ca(2+) removal inhibited the Ca(2+) signals by 90%. In Ca(2+)-free medium, pretreatment with 100 microM NPC-14686 nearly abolished the [Ca(2+)](i) increase induced by 1 microM thapsigargin (an endoplasmic reticulum Ca(2+) pump inhibitor) and abolished the [Ca(2+)](i) increase induced by 2 microM carbonylcyanide m-chlorophenylhydrazone (CCCP) (a mitochondrial uncoupler). NPC-14686 (100 microM) induced a slight [Ca(2+)](i) increase after pretreatment with 2 microM CCCP and 1 microM thapsigargin. Addition of 3 mM Ca(2+) elicited a [Ca(2+)](i) increase in cells pretreated with 100 microM NPC-14686 in Ca(2+)-free medium.
2.Effect of NPC-14686 (Fmoc-l-Homophenylalanine) on Ca²⁺ Homeostasis and Viability in OC2 Human Oral Cancer Cells.
Li YD1, Chou CT2,3, Liang WZ4, Tseng HW5, Fang YC1, Hung TY1, Chang HT6, Kuo DH7, Kuo CC8, Ho CM4, Shieh P7, Chen FA7, Jan CR4. Chin J Physiol. 2015 Oct 31;58(5):285-93. doi: 10.4077/CJP.2015.BAD311.
The effect of the anti-inflammatory compound NPC-14686 on intracellular Ca²⁺ concentration ([Ca²⁺](i)) and viability in OC2 human oral cancer cells was investigated. The Ca²⁺-sensitive fluorescent probe fura-2 was used to examine [Ca²⁺](i). NPC-14686 induced [Ca²⁺](i) rises in a concentration-dependent fashion. The effect was reduced approximately by 10% by removing extracellular Ca²⁺. NPC-14686- elicited Ca²⁺ signal was decreased by nifedipine, econazole, SKF96365, and GF109203X. In Ca²⁺-free medium, incubation with the endoplasmic reticulum Ca²⁺ pump inhibitor thapsigargin or 2,5-di-tert-butylhydroquinone (BHQ) abolished NPC-14686-induced [Ca²⁺](i) rises. Conversely, pretreatment with NPC-14686 abolished thapsigargin or BHQ-induced [Ca²⁺](i) rises. Inhibition of phospholipase C with U73122 abolished NPC-14686-induced [Ca²⁺](i) rises. At 20-100 μM, NPC-14686 inhibited cell viability, which was not reversed by chelating cytosolic Ca²⁺ with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'- tetraacetic acid-acetoxymethyl ester (BAPTA/AM).
3.The mechanism of NPC-14686-induced [Ca²⁺]i rises and non-Ca²⁺-triggered cell death in MG63 human osteosarcoma cells.
Chien JM1, Chou CT, Liang WZ, Kuo DH, Kuo CC, Ho CM, Shieh P, Jan CR. Chin J Physiol. 2014 Jun 30;57(3):158-66. doi: 10.4077/CJP.2014.BAB178.
NPC-14686 has been shown to have anti-inflammatory effect in previous studies, but the mechanisms are unclear. The effect of NPC-14686 on cytosolic Ca²⁺ concentrations ([Ca²⁺]i) and viability in MG63 human osteosarcoma cells was explored. The Ca²⁺-sensitive fluorescent dye fura-2 was applied to measure [Ca²⁺]i. NPC-14686 at concentrations of 100-500 μM induced a [Ca²⁺]i rise in a concentration-dependent manner. The response was reduced by 80% by removing Ca²⁺. NPC-14686 induced Mn²⁺ influx leading to quenching of fura-2 fluorescence. NPC-14686-evoked Ca²⁺ entry was suppressed by nifedipine, econazole, SK&F96365, and protein kinase C inhibitor. Inhibition of phospholipase C with U73122 abolished NPC-14686-induced [Ca²⁺]i rise. At 20-50 μM, NPC-14686 decreased cell viability, which was not reversed by chelating cytosolic Ca²⁺ 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 NPC-14686 (30-50 μM) induced apoptosis in a concentration-dependent manner.
4.Effect of NPC-14686 (Fmoc-L-homophenylalanine) on intracellular Ca2+ levels in human hepatoma cells.
Jan CR1, Kuo SY, Cheng JS, Lo YK, Liu CP, Chen WC. Life Sci. 2003 Apr 25;72(23):2571-80.
The effect of NPC-14686, a potential anti-inflammatory drug, on cytosolic free Ca(2+) levels ([Ca(2+)](i)) in HA22/VGH human hepatoma cells was explored by using fura-2 as a fluorescent Ca(2+) indicator. NPC-14686 at concentrations above 10 microM increased [Ca(2+)](i) in a concentration-dependent manner with an EC(50) value of 100 microM. The Ca(2+) signal was reduced by removing extracellular Ca(2+) or by 10 microM nifedipine and was not changed by verapamil or diltiazem. Pretreatment with 1 microM thapsigargin (an endoplasmic reticulum Ca(2+) pump inhibitor) to deplete the endoplasmic reticulum Ca(2+) abolished 200 microM NPC-14686-induced Ca(2+) release; and conversely pretreatment with NPC-14686 abolished thapsigargin-induced Ca(2+) release. The Ca(2+) release induced by 200 microM NPC-14686 was not changed by inhibiting phospholipase C with 2 microM U73122. Together, the results suggest that in human hepatoma cells, NPC-14686 induced a [Ca(2+)](i) increase by causing store Ca(2+) release from the endoplasmic reticulum in an phospholipase C-independent manner, and by inducing nifedipine-sensitive Ca(2+) influx.
