No abstract available.
Mitochondria* ; Staurosporine*

FLT3 gene mutations occurred in approximately 30% of acute myeloid leukemia (AML) patients, which is closely associated with the occurrence, development and poor prognosis of AML. The therapy targeting at FLT3 mutations might be a promising treatment for AML. Midostaurin can inhibit the activities of III receptor tyrosine kinase encoded by FLT3 gene, induce cell cycle arrest and has a apoptotic effect on primitive AML cells of FLT3 -mutant, FLT3 wild-type and the expression of FLT3 mutated receptor. In view of this, the association between FLT3 mutations and AML, and research advances and clinical applications of midostaurin on the treatment of AML especially for FLT3 mutated AML, are reviewed.
Humans ; Leukemia, Myeloid, Acute ; Mutation ; Staurosporine ; analogs & derivatives

[Ca2+]i transients by reverse mode of cardiac Na+/Ca2+ exchanger (NCX1) were recorded in fura-2 loaded BHK cells with stable expression of NCX1. Repeated stimulation of reverse NCX1 produced a long-lasting decrease of Ca2+ transients ('rundown'). Rundown of NCX1 was independent of membrane PIP2 depletion. Although the activation of protein kinase C (PKC) was observed during the Ca2+ transients, neither a selective PKC inhibitor (calphostin C) nor a PKC activator (PMA) changed the degrees of rundown. By comparison, a non-specific PKC inhibitor, staurosporine (STS), reversed rundown in a dose-dependent and reversible manner. The action of STS was unaffected by pretreatment of the cells with calphostin C, PMA, or forskolin. Taken together, the results suggest that the stimulation of reverse NCX1 by STS is independent of PKC and/or PKA inhibition.
Forskolin ; Fura-2 ; Membranes ; Naphthalenes ; Protein Kinase C ; Staurosporine

PURPOSE: In order to determine whether the Tonicity responsive enhancer binding protein (TonEBP) is expressed by hypertonic and hyperosmolar stress, TonEBP expression was investigated in the retinal ganglion cell (RGC) line, RGC-5 cells. METHODS: After RGC-5 cells were cultured by Staurosporine, TonEBP expression was measured with Western immunoblotting analysis and real-time reverse transcription-polymerase chain reaction in 50 mM NaCl, 100 mM mannitol, 50 mM glucose, or 100 mM glucose at 3, 6, 12, and 24 hours after exposure to each environment. RESULTS: In this study, the protein expression of TonEBP was determined to be statistically significantly checked in 50 mM NaCl after 3, and 6 hours, in 100 mM mannitol after 6 hours, and in 100 mM glucose after 3, and 6 hours. TonEBP messenger Ribonucleic acid (mRNA) expression was determined to be statistically significantly checked in 50 mM NaCl after 3 hours, in 100 mM mannitol after 3, and 24 hours, and in 50 mM glucose after 3, and 24 hours. CONCLUSIONS: These results suggested that TonEBP was expressed by hypertonic and hyperosmolar stress at the protein and mRNA levels. Further studies are nedded to determine the role of TonEBP and the mechanism of expression and regulation of TonEBP.
Blotting, Western ; Glucose ; Mannitol ; NFATC Transcription Factors ; Osmotic Pressure ; Retinal Ganglion Cells ; RNA ; RNA, Messenger ; Staurosporine

Calbindin-D28K has been implicated in the regulation of neuronal cell death. Previously, we demonstrated that calbindin-D28K prevents staurosporine (STS)-induced caspase activation and subsequent apoptosis in a neuronal cell line. However, the role of calbindin-D28K in STS-induced activation of calpain and necrotic cell death was not identified. Staurosporine induced the elevation of intracellular calcium after 1 hr of treatment. Overexpression of calbindin-D28K and presence of a calcium chelator, BAPTA, prevented the increase of calcium in STS-treated cells. Cleavage of Bax by calpain was prevented by the overexpressed calbindin-D28K. Permeabilization of the plasma membrane, a factor in necrosis, as well as apoptotic change of the nucleolus induced by STS, was prevented by calbindin-D28K. Thus, our study suggests that calbindin-D28K may exert its protective functions by preventing calpain activation in necrotic cell death, in addition to its effect on the caspase-apoptosis pathway.
Apoptosis ; Calbindin 1* ; Calcium ; Calpain ; Cell Death ; Cell Line ; Cell Membrane ; Membranes* ; Necrosis ; Neurons ; Staurosporine

Authors studied the regulatory mechanism of protein kinase C on the action of acetylcholine in rabbit carotid artery. The arterial rings were myographied isometrically in an isolated organ bath. In this study, acetylcholine relaxed phenylephrine-induced contraction of rabbit carotid artery in the presence of endothelium. In the pretreatment of methylene blue or nitro-L-arginine, the action of acetylchioline was reduced. Pretreatment of phorbol 12-myristate 13-acetate(PMA) attenuated the action of acetylcholine, but PMA did not attenuated it in the presence of staurosporine, suggesting that protein kinase C suppressed the action of acetylcholine. The potency of phorbol ester on the action of acetylcholine was PMA>phorbol 12, 13-dibutyrate(PDBu)>phorbol 12,13-diacetate(PDA), but the direct effect of phorbol on the contraction of arterial rings was PDBu>PMA>PDA. This implied that protein kinase C involved in the contraction of smooth muscle and the attenuation of the action of acetylcholine were different. PMA did not affect on A23187- and sodium nitroprusside-induced vasorelaxation. Acetylcholine increased tissue cGMP contents, which was reduced by PMA. These results suggest that in rabbit carotid artery protein kinase C reduce acetylcholine-stimuated endothelium derived relaxing factor(EDRF) release by affecting membrane receptor, and do not affect on the function of EDRF and cGMP production in the smooth muscle.
Acetylcholine* ; Baths ; Carotid Arteries* ; Endothelium ; Membranes ; Methylene Blue ; Muscle, Smooth ; Protein Kinase C ; Sodium ; Staurosporine ; Vasodilation

BACKGROUND: Impairment of relaxing response and augmentation of contractile response to vasoactive substances have been reported in atherosclerotic arteries. These alterations in vascular reactivity are considered as an underlying mechanism for the development of acute vasospasm in atherosclerotic coronary artery. Recently, it has been reported that lysophophatidylcholine (LPC), an oxidative metabolite of low density lipoprotein causes this functional abnormality. However, the precise mechanism of LPC induced change of vascular reactivity is still uncertain. METHOD: In this study, to elucidate the underlying mechanisms of abnormal vascular reactivity in atherosclerotic coronary artery, we examined the effect of LPC on whole cell K+current using patch clamping technique in rabbit coronary smooth muscle cells. RESULTS: Application of LPC(1microM) showed dual effect on whole cell outward current which depends on the magnitude of test potentials. At relatively high depolarizing test potentials (> 10 mV), LPC increased amplitude of outward current which was blocked by Gd3+ not by iberiotoxin (100 nM) and TEA (1 mM). Reversal potential of this Gd3+sensitive, LPC-induced current was -9.7 +/- 0.6 mV. At less depolarizing test potentials (< 10 mV), LPC decreased whole cell K+currents in a dose dependent manner (from 0.01 to 10 microM) in the range of -30 mV to +0 mV. Half maximal inhibition of K+current was 1.509 microM at 0 mV test potential (n =5). Depolarizing holding potential (0 mV) prevented this LPC-induced inhibition of K+current. Steady state activation and inactivation parameters of K+current were significantly shifted to the positive direction by application of LPC (p < 0.01, n =8). Pretreatment of staurosporine (100 nM), a blocker of protein kinase C partially blocked LPC-induced decrease of K+currents. CONCLUSION: LPC-induced inhibition of voltage dependent K+current may explain abnormal vascular reactivity in atherosclerotic coronary artery.
Arteries ; Constriction ; Coronary Vessels ; Lipoproteins ; Lysophosphatidylcholines* ; Muscle, Smooth* ; Myocytes, Smooth Muscle* ; Protein Kinase C ; Staurosporine ; Tea

OBJECTIVE: A major limiting factor in human cancer chemotherapy is toxicity in normal cells and tissues. Our goal was to determine whether normal proliferating cells could be protected from chemotherapeutic agents by taking advantage of the differential drug sensitivity of cell cycle G1 checkpoint in normal and cancer cells. METHODS: Normal peripheral blood mononuclear cells (PBMC) and ovarian cancer cell lines (OVCAR- 3 and SKOV-3) were initially treated with 10 nM of staurosporine for 48 hours. After removal of staurosporine contained media, both PBMC and ovarian cancer cells were treated with 20 nM of paclitaxel for 24 hours. Cells were then allowed to recover in drug-free medium for 4 days. The DNA contents and cell cycle changes were detected by FACScan flow cytometer in the cells harvested whenever the medium was changed. RESULTS: After pretreatment of ovarian cancer cell lines (OVCAR-3 and SKOV-3) with 10 nM of staurosporine followed by treatment with 20 nM of paclitaxel, both OVCAR-3 and SKOV-3 cells were selectively arrested in G2M phase of cell cycle by paclitaxel and they resumed their proliferative cycle to some extents after the drugs were removed and cultured with fresh media. However. pretreatment with 10 nM of staurosporine protected normal circulating PBMC that had been induced to proliferate in vitro with phytohemagglutinin from paclitaxel. Staurosporine-induced arrest of PBMC in G0/G1 phase was reversible, and arrested cells tolerated 10 nM of paclitaxel in culture. CONCLUSION: OVCAR-3 and SKOV-3 cancer cells can be targeted specifically with paclitaxel, following staurosporine-mediated, selective and reversible G0/G1 arrest in PBMC.
Cell Cycle ; Cell Line ; Cytoprotection ; DNA ; Drug Therapy* ; Humans ; Ovarian Neoplasms ; Paclitaxel ; Staurosporine

OBJECTIVE: The effects of the staurosporine on contraction of self-assembled constructs and extracellular matrix syntheses of goat temporomandibular joint discs were investigated. METHODS: Goat temporomandibular joint disc cells were isolated and cultured to P3, and 5.5×10⁶ cells were combined with different concentrations of staurosporine (0, 0.1, 1, 10, 100 nmol·L⁻¹) in agarose wells and cultured for one week. The samples were frozen and sectioned. Safranin-O,  Picro-sirius red and immunohistochemical staining were performed to observe the distributions of the extracellular matrix and the expression of alpha-smooth muscle actin (α-SMA). Enzyme linked immunosorbent assay (ELISA) and Blyscan kits were utilized to quan--titatively detect the contents of type Ⅰ collagen (ColⅠ) and glycosaminoglycans (GAGs). RESULTS: Each group of goat temporo-mandibular joint disc cells in the agarose wells were gathered to self-assemble into a disc-shaped base for 4 hours and then to gradually contract into a round shape. The Picro-sirius red staining was strong and indicated collagen distribution. The Safranin-O staining observed GAGs throughout the entire construct. The expression of ColⅠ was strongly posi-tive in the staurosporine groups; however, the expression of α-SMA was weak. ColⅠ and GAGs contents in the stau-rosporine groups were greater than that of the control group, especially in the 10 nmol·L⁻¹ group (P<0.01). CONCLUSIONS Staurosporine has a certain effect on the shrinkage of self-assembled constructs; however, such effect is not prominent. Staurosporine contributes to the construction synthesis of extracellular matrix.
Animals ; Collagen Type I ; Glycosaminoglycans ; Goats ; Staurosporine ; pharmacology ; Temporomandibular Joint ; Temporomandibular Joint Disc ; cytology ; drug effects

The present study was undertaken to examine the role of phospholipase A2 (PLA2) in oxidant-induced inhibition of phosphate transport in primary cultured rabbit renal proximal tubule cells. Uptakes of phosphate and glucose were dose-dependently inhibited by an oxidant t-butylhydroperoxide (tBHP), and the significant inhibition appeared at 0.025 mM of tBHP, whereas tBHP-induced alterations in lipid peroxidation and cell viability were seen at 0.5 mM. tBHP stimulated arachidonic acid (AA) release in a dose-dependent fashion. A PLA2 inhibitor mepacrine prevented tBHP-induced AA release, but it did not alter the inhibition of phosphate uptake and the decrease in cell viability induced by tBHP. tBHP-induced inhibition of phosphate transport was not affected by a PKC inhibitor, staurosporine. tBHP at 0.1 mM did not produce the inhibition of Na+-K+-ATPase activity in microsomal fraction, although it significantly inhibited at 1.0 mM. These results suggest that tBHP can inhibit phosphate uptake through a mechanism independent of PLA2 activation, irreversible cell injury, and lipid peroxidation in primary cultured rabbit renal proximal tubular cells.
Arachidonic Acid ; Cell Survival ; Glucose ; Lipid Peroxidation ; Phospholipases A2* ; Phospholipases* ; Quinacrine ; Staurosporine ; tert-Butylhydroperoxide