Animals ; Endothelium, Vascular ; drug effects ; Humans ; Pyrazines ; pharmacology

Experimental data suggest that Resveratrol, a compound found in grapes and other fruits may influence cell proliferation and apoptosis. The aim of our experiments was to study the effect of Resveratrol on tumor cell cultures and an endothelial cell culture in order to examine the effect of various doses of this compound on active cell death and cell proliferation. Human tumor (HT-29, SW-620, HT-1080) and endothelial (HUV-EC-C) cells were treated with various doses of (0.1 to 100.0 microg/ml) Resveratrol in vitro. Cell number, apoptotic and mitotic index was measured 24, 48 and 72 h after treatment. Low doses (0.1-1.0 microg/ml) of Resveratrol enhance cell proliferation, higher doses (10.0-100.0 microg/ml) induce apoptosis and decrease mitotic activity, which is reflected in changes of cell number. Resveratrol influences dose dependently the proliferative and apoptotic activity of human tumor and endothelial cells. The possible role of formaldehyde in the mechanism of action of Resveratrol is discussed.
Antineoplastic Agents, Phytogenic/pharmacology* ; Apoptosis* ; Cells, Cultured ; Dose-Response Relationship, Drug ; Endothelium/drug effects* ; Endothelium/cytology ; Human ; Mitosis/drug effects* ; Stilbenes/pharmacology* ; Tumor Cells, Cultured

OBJECTIVETo explore the effect of genistein on proliferation of human endometrial endothelial cells (HEECs) and glandular epithelium.

METHODSIn vitro HEECs and human endometrial cancer-1B cell (HEC-1B) were cultured with 0, 1, 10, 50, 100, and 200 micromol/L of genistein alone or indicated concentrations of genistein combined with 0.2 or 1 nmol/L 17beta-estradiol (17beta-E2). Cell proliferation was determined by [3H]-thymidine incorporation and cell cycle was measured by flow cytometry.

RESULTSAfter 96 hours of treatment, genistein inhibited the proliferation of HEECs in a dose-dependent manner. The stimulation index reduced from 100% (without genistein treatment) to about 1% (200 micromol/L genistein). HEECs were arrested at G1/0 and G2/M phase when treated with genistein for 96 hours. When the concentration of genistein was 200 micromol/L, the percentages of HEECs at G1/0, G2/M, and S phase were 96.0%, 2.1%, and 1.9%, respectively. However, when HEECs were treated without genistein, the percentages of HEECs at G1/0, G2/M, and S phase were 76.7%, 8.5%, and 14.7%, respectively. 17beta-E2 could not influence the effects of genistein on the proliferation of HEECs. Meanwhile, genistein could suppress the proliferation of HEC-1B. If the stimulation index of HEC-1B was defined as 100% when HEC-1B was treated with different doses of 17beta-E2 (without genistein), it was 67%, 19%, as well as 32% when cell was supplemented with 200 micromol/L genistein combined with 0, 0.2, or 1 nmol/L 17beta-E2, respectively.

CONCLUSIONGenistein at the concentration of 200 micromol/L can sufficiently inhibit the proliferation of HEECs and endometrial glandular epithelium simultaneously in vitro.

Cell Cycle ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Endometrium ; cytology ; drug effects ; Endothelium ; cytology ; drug effects ; Female ; Flow Cytometry ; Genistein ; pharmacology ; Humans

AIMTo compare the differences of pharmacological characteristics of the endothelial target for acetylcholine (ETA) between rat aorta and tail artery.

METHODSDifferences in the endothelium-dependent relaxation induced by acetylcholine (ACh: 10(-8) - 10(-4) mol/L) were studied using isolated rat tail artery helical strips and aortic rings, so that the pharmacological characteristics of ETA in small artery can be observed.

RESULTSACh-induced endothelium-dependent relaxation was observed both in rat tail artery strips and in aortic rings precontracted with potassium chloride (60 mmol/L) in a concentration-dependent manner. In tail artery this effect was partially blocked by L-N(omega)-Nitro-arginine methyl ester (L-NAME: 10(-4) mol/L) or methylene blue (MB: 10(-5) mol/L), together with indomethacin (Indo: 10(-4) mol/L), but in aorta it was completely blocked by L-NAME or MB.

CONCLUSIONIt is different of the pharmacological characteristics of ETA between big artery and small artery. A non-NO and non-PGI2 relaxing factor, together with nitric oxide (NO) and prostacyclin (PGI2), mediates endothelium-dependent vasorelaxation induced by ACh in small artery, but NO may be the principal endothelial vasodilator substance in big artery.

Acetylcholine ; pharmacology ; Animals ; Aorta ; drug effects ; Arteries ; drug effects ; Endothelium, Vascular ; drug effects ; physiology ; In Vitro Techniques ; Male ; Rats ; Rats, Wistar ; Vasodilation ; drug effects

OBJECTIVETo investigate the vasorelaxant effect of taurine (Tau) in rat aortic rings and the mechanism.

METHODThe isolated thoracic aortic rings of male Wistar rats were mounted on the organ bath. The effect of Tau 10, 20, 40, 80 mmol x L(-1) on the rings with endothelium intact or endothelium denuded precontracted by the phenylephrine (1 micromol x L(-1)) or KCl (60 mmol x L(-1)), and the effect of Tau on the vessel reaction induced by various drugs were recorded with biological signal analytical system.

RESULTTaurine completely relaxed the contractions induced by KCl and phenylephrine in a concentration-dependent manner in endothelium-intact and endothelium-denuded rat aorta. Taurine attenuated the contraction to PE both in the absence and presence of calcium, but had no significant effect on the contraction induced by caffeine. The relaxant effect of taurine was significantly inhibited by pretreatment of endothelium-denuded aorta with potassium channel antagonists glibenclamide and tetraethylamine but not by BaCl2 or 4-aminopyridine.

CONCLUSIONTaurine induces an endothelium-independent relaxation in rat aortic rings. The mechanisms may involve the reduction in Ca2+-influx and Ca2+-release and the participation of the potassium channels (KATP and KCa, but not Kir or KV).

Animals ; Aorta ; drug effects ; physiology ; Endothelium, Vascular ; drug effects ; physiology ; Male ; Models, Animal ; Muscle Relaxation ; drug effects ; Rats ; Rats, Wistar ; Taurine ; pharmacology ; Vasodilation ; drug effects ; Vasodilator Agents ; pharmacology

The change of endothelial cell viability due to corticosteroid treatment in stored rabbit corneas was investigated. Hydrocortisone was injected into the anterior chamber of enucleated eyeballs which were stored in a moist chamber. After 24,48, or 72 hours of storage, the cornea was removed and stained with trypan blue. The unstained endothelial cells were counted under the light microscope in order to determine the density of viable endothelial cells. The same procedures were done on the contralateral eye with normal saline injected into the anterior chamber instead of hydrocortisone as a control. The density of viable endothelial cells in the corticosteroid-treated group was higher than that of the control group by 1.75%,14.39%, and 27.40% in 24,45, and 72 hour-stored corneas, respectively.
Animals ; Cell Survival/drug effects ; Endothelium, Corneal/*drug effects ; Female ; Hydrocortisone/*pharmacology/physiology ; Male ; Rabbits ; Time Factors ; Tissue Preservation/*methods

OBJECTIVESTo investigate the effects of glucose and free fatty acids (FFAs) on the proliferation and cell cycle of human vascular endothelial cells in vitro, and to examine whether the combined presence of elevated FFAs and glucose may cross-amplify their individual injurious effects.

METHODSCultured human vascular endothelial cells (ECV304) were incubated with various concentrations of glucose and/or FFAs (palmitate and/or oleate) for 24 - 96 h. Morphologic alterations were observed using a phase contrast microscope and an electron microscope. Inhibition of proliferation was measured by a colorimetric 3-[4, 5-dimethyl thiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay. Cell viability was determined using trypan blue exclusion. Distribution of cells along phases of the cell cycle was analyzed by flow cytometry.

RESULTSGlucose 15 or 30 mmol/L, palmitate (PA) 0.25 or 0.5 mmol/L, and oleate (OA) 0.5 mmol/L inhibited proliferation and accelerated death of endothelial cells in a dose-and-time-dependent manner. After treatment with elevated glucose and/or FFAs, the G(0)/G(1) phase cells increased, whereas S phase cells decreased, suggesting that high glucose and/or FFAs mainly arrested endothelial cells at G(0)/G(1) phase. The inhibitive rates of proliferation and population of dead cells in endothelial cells incubated with glucose plus FFAs (glucose 30 mmol/L + PA 0.25 mmol/L, glucose 30 mmol/L + OA 0.5 mmol/L, glucose 30 mmol/L + PA 0.25 mmol/L + OA 0.5 mmol/L) increased more markedly than those treated with high glucose or FFAs (PA and/or OA) alone.

CONCLUSIONBoth high ambient glucose and FFAs can inhibit proliferation and accelerate death of endothelial cells in vitro. These changes were cross-amplified in the combined presence of high levels of glucose and FFAs.

Cell Division ; drug effects ; Cell Survival ; drug effects ; Cells, Cultured ; Endothelium, Vascular ; cytology ; Fatty Acids, Nonesterified ; pharmacology ; Glucose ; pharmacology ; Humans

AIMTo examine the effect of HO-1 inducer hemin on hydrogen peroxide (H2O2) caused decrease in contraction of isolated rat aortic rings, and to elucidate the underlying mechanism.

METHODSThe thoracic aortic rings with endothelium of male Sprague-Dawley rats were mounted on a bath system. Isometric contractions of aortic rings were measured.

RESULTS(1) After intraperitoneal injection of HO-1 inducer hemin, HO-1 activity of thoracic aorta and COHb concentration in rat blood enhanced. And it also prevented the decrease in contraction responses to PE which pretreatment of arteries with 300 micromol/L H2O2. (2) Pretreatment of ATP-sensitive potassium channel inhibitor glibenclamide, but not GC inhibitor methylene blue, could partly abolish the protection of hemin in arteries with H2O2 exposure. (3) Hemin could not influence the shift of concentration-response curve to [Ca2+]o in arteries with H2O2 exposure. (4) In Ca(2+) -free K-H solution, exposure of H2O2 reduced caffeine and PE-induced constriction in the rat aortic rings. After pretreatment of hemin, could prevent the decrease in contraction responses to caffeine and PE.

CONCLUSIONIncrease in HO-1 activity could prevent the H2O2 induced decrease in contraction responses to PE in intact aortic rings. The mechanism might be involved in activation of ATP-sensitive potassium channel and mobilization of intracellular calcium stores, but had no relationship with the GC pathway.

Animals ; Aorta, Thoracic ; drug effects ; physiology ; Endothelium, Vascular ; Heme Oxygenase-1 ; pharmacology ; Hydrogen Peroxide ; adverse effects ; KATP Channels ; drug effects ; Male ; Rats ; Rats, Sprague-Dawley ; Vasoconstriction ; drug effects

Pingyangmycin (bleomycin A5 hydrochloride, PYM) is one of the anti-neoplastic agents which have been commonly used to treat venous malformations. However, the underlying mechanism by which PYM treats venous malformations remains poorly understood. It was reported that venous endothelial cells could recruit neutrophils via adhesion molecules (E-selectin, ICAM-1, ICAM-3, VCAM-1) during the acute/chronic inflammation and subsequent histological fibrosis after sclerotherapy with PYM. This study explored if the expression of E-selectin, ICAM-1, ICAM-3 and VCAM-1 in human venous malformation endothelial cells could be affected by PYM. HVMECs were cultured from human venous malformation tissue. Expressions of E-selectin, ICAM-1, ICAM-3 and VCAM-1 on HVMECs in response to PYM were analyzed by cell ELISA. The relative levels of mRNA expression in the cells were semi-quantified. The results showed that PYM up-regulated the expressions of E-selectin, ICAM-3, VCAM-1 and ICAM-1 in both time- and concentration-dependent manner. Our findings suggested that PYM could induce the expression of adhesion molecules in HVMECs, which might be a possible mechanism by which sclerotherapy by intralesional injection of PYM treats venous malformations.
Bleomycin ; analogs & derivatives ; pharmacology ; Cell Adhesion Molecules ; genetics ; metabolism ; Cells, Cultured ; Endothelial Cells ; drug effects ; metabolism ; Endothelium, Vascular ; drug effects ; metabolism ; Gene Expression ; drug effects ; genetics ; Humans

Oxidized low density lipoprotein (oxLDL) can trigger intracellular production of reactive oxygen species and lipid peroxidation (LPO), and is thought to contribute to initiation and progression of atherosclerosis. In order to understand the correlation between oxLDL and macromolecular damage, we measured levels of LPO-derived miscoding etheno-DNA adducts and LPO-modified proteins in cultured human vascular endothelial and smooth muscle cells after incubation with oxLDL for up to 48 h. A semi-quantative analysis method for 1, N6-ethenodeoxyadenosine (ɛdA) by immunohistochemistry was applied. After oxLDL stimulation, ɛdA-stained nuclei were significantly increased in both endothelial and smooth muscle cells. Similarly, 4-hydroxy-2-nonenal (4-HNE)-modified proteins, as analyzed by immunohistochemistry and Western blotting, were also 3-5 fold increased. It was concluded LPO-derived etheno-DNA adducts and LPO-modified proteins are strongly induced by oxLDL in human vascular endothelial and smooth muscle cells. This macromolecular damage may contribute to the dysfunction of arterial endothelium and the onset of atherosclerosis.
DNA ; metabolism ; Endothelium, Vascular ; cytology ; drug effects ; metabolism ; Humans ; Lipid Peroxidation ; drug effects ; Lipoproteins, LDL ; pharmacology ; Muscle, Smooth ; cytology ; drug effects ; metabolism ; Proteins ; metabolism