This study examined the effect of artesunate (Art) on the proliferation, DNA replication, cell cycles and apoptosis of vascular smooth muscle cells (VSMCs). Primary cultures of VSMCs were established from aortas of mice and artesunate of different concentrations was added into the medium. The number of VSMCs was counted and the curve of cell growth was recorded. The activity of VSMCs was assessed by using MTT method and inhibitory rate was calculated. DNA replication was evaluated by [3H]-TdR method and apoptosis by DNA laddering and HE staining. Flowmetry was used for simultaneous analysis of cell apoptosis and cell cycles. Compared with the control group, VSMCs proliferation in Art interfering groups were inhibited and [3H]-TdR incorprating rate were decreased as well as cell apoptosis was induced. The progress of cell cycle was blocked in G0/G1 by Art in a dose-dependent manner. It is concluded that Art inhibits VSMCs proliferation by disturbing DNA replication, inducing cell apoptosis and blocking cell cycle in G0/G1 phase.
Aorta/cytology ; Apoptosis/*drug effects ; Artemisinins/*pharmacology ; Cell Cycle/drug effects ; Cells, Cultured ; DNA Replication/*drug effects ; Muscle, Smooth, Vascular/*cytology ; Sesquiterpenes/*pharmacology

OBJECTIVETo investigate the effects of tanshinone IIA (TA, one of the active components of Salvia miltiorrhiza Bge), on the proliferation of cultured rat vascular smooth muscle cells (VSMC), and to clarity the probable mechanism.

METHODCell culture technique was used in vitro and treated with or without 10% FBS. The inhibitory effect of TA on proliferation of VSMC was observed by cell count, MTU metabolism measuring and BrdU incorporation assay. Flow cytometry was performed to track cell cycle progression. Western bolts were performed to evaluate ERK1/2 activity. The expression of c-fos was examined by RT-PCR.

RESULTThe results of cell number, MTU assay and BrdU incorporation showed that TA cound significantly inhibit 10% FBS induced proliferation in a dose-dependent manner. Flow cytometry (FCM) analysis indicated that the G5/G1 phase fraction ratio of TA group was higher than that of 10% FBS group, while the S-phase fraction ratio was lower than that of 10% FBS group. Western blot's results displayed that TA inhibited the phosphorylation of ERK1/2, and in accordance with this findings. TA could decrease the early elevation of c-fos expression.

CONCLUSIONThese results suggest that TA can inhibit 10% FBS induced the proliferation of VSMC. This effect may be related to its blocking VSMCs cell cycle in G0/G1 phase, inhibiting of the ERK1/2 activity, and decreasing the expression of c-fos.

Animals ; Aorta ; cytology ; drug effects ; Cell Cycle ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Diterpenes, Abietane ; Down-Regulation ; Gene Expression ; drug effects ; Myocytes, Smooth Muscle ; cytology ; drug effects ; Phenanthrenes ; pharmacology ; Proto-Oncogene Proteins c-fos ; genetics ; metabolism ; Rats

BACKGROUNDDicycloplatin is a relatively safe third generation platinum-complex anti-cancer drug. The present study focused on the effects of dicycloplatin on in vitro proliferation and apoptosis of human aortic smooth muscle cells (HASMC) and human aortic endothelial cells (HAEC).

METHODSProliferation of HASMC and HAEC, DNA content, and cellular levels of proliferation- and apoptosis-related proteins were assessed using the (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) (MTS) assay, flow cytometry and Western blotting assays, respectively.

RESULTSDicycloplatin at 10 ng/ml significantly inhibited HASMC proliferation, however, 10 µg/ml were required to significantly inhibit HAEC proliferation. Cell cycle analysis showed that dicycloplatin was a non-specific inhibitor of the cell cycle. Although dicycloplatin significantly decreased proliferating cell nuclear antigen (PCNA) expression in HASMC at all concentrations tested, it did not significantly affect PCNA expression in HAEC; Bax and p53 protein expression was upregulated in dicycloplatin groups.

CONCLUSIONSDicycloplatin at nanogram concentrations significantly inhibits HASMC proliferation, although the effect is relatively weaker than that of sirolimus. In contrast, the effect of dicycloplatin on inhibition of HAEC proliferation is much less pronounced than that on HASMC. The latter characteristics point to the potential for use of dicycloplatin in drug-eluting stents.

Aorta ; cytology ; Blotting, Western ; Cell Proliferation ; drug effects ; Drug Combinations ; Drug-Eluting Stents ; Endothelial Cells ; cytology ; drug effects ; Flow Cytometry ; Glutamates ; pharmacology ; Humans ; Muscle, Smooth, Vascular ; cytology ; drug effects ; Organoplatinum Compounds ; pharmacology ; Sirolimus ; pharmacology

OBJECTIVETo study the effect of THW-4, an extract from Trypterygium hypoglaucum on proliferation and apoptosis of vascular smooth muscle cells (VSMC).

METHODSVSMC derived from rabbit aorta were cultured in vitro and different concentrations of THW-4 were added in experimental groups. Cell proliferation was evaluated by MTT and apoptosis by transmission electron microscopy (TEM), TUNEL assay and Annexin V-FITC/PI double labelled assay.

RESULTSThe inhibitory effects of THW-4 on proliferation of VSMC displayed dose-time dependently, with the IC50 value of 15.6 microg/L at 48 hrs. Incubated with THW-4 (10-100 microg/L) for 56 hrs, VSMC mainly appeared early stage apoptosis and the percentage of apoptosis was found to raise along with the increase of the THW-4 concentration. Typical images of apoptosis could be observed under TEM and TUNEL assay showed increase of DNA segments with karyorrhexis and pyknosis after THW-4 treatment for 72 hrs. Analysis of cell cycle indicated the THW-4 mainly lead to the blockage of VSMC in G2/M stage.

CONCLUSIONTHW-4 could inhibit the proliferation and induce the apoptosis of VSMC in vitro, suggesting that THW-4 is a potential agent for prevention of restenosis following angioplasty.

Animals ; Aorta ; cytology ; Apoptosis ; drug effects ; Cell Division ; drug effects ; Cells, Cultured ; Coronary Restenosis ; prevention & control ; Drugs, Chinese Herbal ; pharmacology ; Male ; Muscle, Smooth, Vascular ; cytology ; Rabbits ; Tripterygium ; chemistry

The aim of this study was to elucidate the effects of anti-hypertensive drugs, nifedipine, furosemide, hydrochlorothiazide, captopril, and atenolol on DNA synthesis and proliferation of cultured rat aortic smooth muscle cells induced by fetal calf serum. Aortic smooth muscle cells from Sprague-Dawley rats were isolated, cultured, and seeded in multi-well plates. When confluent, cells were cultured in a conditioned medium without fetal calf serum. After 72 hours, cells were cultured in the medium retaining 10% fetal calf serum with or without anti-hypertensive drugs by increasing the concentration between 10(-8) and 10(-4) M. DNA synthesis was assessed by [3H]-thymidine uptake and proliferation by cell numbers using a hemocytometer. Nifedipine at a concentration of 10(-5) M and 5 x 10(-5) M inhibited serum-induced DNA synthesis significantly by 50.8% and 86.6%, respectively (p < 0.05). The results of cell numbers paralleled those of 3H-thymidine incorporation. Serum-induced DNA synthesis was also reduced by 32.6% at the highest dose of furosemide (10(-4) M), but there was no statistical significance. Hydrochlorothiazide, captopril, and atenolol did not show anti-proliferative effect throughout any of the doses. In conclusion, among the various anti-hypertensive drugs, nifedipine seems to be most beneficial in view of its direct inhibitory effect on DNA synthesis and proliferation of smooth muscle cells, as well as for its anti-hypertensive effect.
Animal ; Antihypertensive Agents/pharmacology* ; Aorta/metabolism* ; Aorta/drug effects* ; Cell Division/drug effects ; Cells, Cultured ; DNA/biosynthesis* ; Male ; Muscle, Smooth, Vascular/metabolism* ; Muscle, Smooth, Vascular/drug effects* ; Muscle, Smooth, Vascular/cytology ; Rats ; Rats, Sprague-Dawley

AIMIn order to evaluate the regulatory effects of nucleotides and adenosine on ATP-sensitive potassium channel (K(ATP)) in artery smooth muscles, the effects of them on vascular relaxation induced by K(ATP) opener pinacidil(Pin) were investigated.

METHODSThe isolated endothelium- denuded aorta rings were preincubated with nucleotides or nucleotides and glibenclamide (Gli) for 10 min, the vascular relaxation induced by Pin in aorta precontracted with 20 mmol x L(-1) KCl was observed.

RESULTSAfter the isolated endothelium-denuded aorta rings were preincubated with ATP, ADP, UDP, GTP and adenosine (Ade) 100 micromol x L(-1) respectively, the vascular relaxation induced by Pin was changed as following: (1) ATP could inhibit the K(ATP) activation by Pin and enhance the blockade of K(ATP) by Gli. (2) ADP could inhibit the K(ATP) activation by Pin and attenuate the blockade of K(ATP) by Gli. (3) The regulatory effect of Ade on K(ATP) was similar with that of ADP. (4) UDP could enhance the K(ATP) activation by Pin and attenuate the blockade of K(ATP) by Gli. (5) GTP could enhance the K(ATP) activation by Pin, but had no effects on the blockade of K(ATP) by Gli.

CONCLUSIONNucleotides and adenosine, related to energy metabolism, could modulate the functions of K(ATP) in vascular smooth muscle. But their pharmacological characteristics were different.

Animals ; Aorta ; cytology ; drug effects ; Glyburide ; pharmacology ; In Vitro Techniques ; KATP Channels ; metabolism ; Male ; Muscle, Smooth, Vascular ; drug effects ; Nucleotides ; pharmacology ; Pinacidil ; pharmacology ; Rats ; Rats, Wistar ; Vasodilator Agents ; pharmacology

AIMTo study the effect of puerarin on vascular endothelial cells apoptosis induced by chemical hypoxia-ischemia in vitro.

METHODSThe chemical hypoxia-ischemia model was performed by treating cultured bovine aortic endothelial cells (BAECs) with NaCN in glucose-free medium. Cell viability was determined by trypan blue staining. Cell apoptosis was defined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), flow cytometry and Hoechst 33342 staining. The expression of Caspase-3 in endothelial cells was detected by immunocytochemical method.

RESULTSChemical hypoxia-ischemia was shown to initiate bovine aortic endothelial cell apoptosis. Puerarin (0.5-3 mmol.L-1) was found to inhibit endothelial cell apoptosis effectively, and reduce the expression of Caspase-3 significantly.

CONCLUSIONPuerarin can protect apoptotic endothelial cells induced by chemical hypoxia-ischemia markedly and the effect was performed partly by decreasing Caspase-3 expression.

Animals ; Aorta, Thoracic ; cytology ; Apoptosis ; Caspase 3 ; Caspases ; metabolism ; Cattle ; Cell Hypoxia ; drug effects ; Cells, Cultured ; DNA Damage ; drug effects ; Endothelium, Vascular ; cytology ; drug effects ; Isoflavones ; pharmacology ; Protective Agents ; pharmacology

AIMTo explore the effects of sinomenine(Sin) on intracellular free calcium ([Ca2+]i) and the activity of PKC (protein kinase C) of the cultured aortic vascular smooth muscle cells (VSMC) during ischemia and hypoxia.

METHODSThe effect of Sin on changes in [Ca2+]i were determined in cultured rabbit VSMC after exposure to high K+, norepinephrine (NE) and caffeine (Caf). Fluorescent Ca2+ -indicater fura-2/AM was used. The effects of Sin were compared with that of verapamil (Ver). The hypoxia model was made, then the activity of PKC was measured by y scintillation counting instrument.

RESULTSSin (10 x 10(-6) mol x L(-1), 3 x 10(-5) mol x L(-1) 10(-4) mol x L(-1)) inhibited the elevation of [Ca2+]i induced by high K+ -depolarization in a concentration dependent manner. In addition, Sin inhibited the elevation of [Ca2+]i induced by NE in the presence of extracellular Ca2+. In the absence of extracellular Ca2+, Sin (3 x 10(-5) mol.L(-1)) also had no blocking effect on the NE-induced [Ca2+]i increase. It was found that the activity of PKC treated with Sin in VSMC cytoplasm and cell membrane in normal condition increased, the activity of PKC in cytoplasm in ischemia and hypoxia situation increased, but the activity of PKC in cell membrane decreased. When VSMC was treated with Sin, the activity of PKC in cytoplasm decreased and that of cell membrane increased.

CONCLUSIONThe results suggest that Sin might decrease the[Ca2+] i of VSMC by blocking both VDC and ROC, could regulate the PKC activities induced by ischemia and hypoxia.

Animals ; Aorta ; cytology ; drug effects ; Calcium ; metabolism ; Cell Hypoxia ; Cells, Cultured ; Cytoplasm ; metabolism ; Morphinans ; pharmacology ; Muscle, Smooth, Vascular ; cytology ; drug effects ; Myocytes, Smooth Muscle ; drug effects ; metabolism ; physiology ; Protein Kinase C ; metabolism ; Rabbits

Migration of adventitial fibroblasts (AF) is involved in the neointimal formation which is one of the common pathological processes in several vascular diseases. The observation of whether the migratory response of AF from hypertensive animal is different from that of controls may provide an explanation of vascular remodeling in hypertension. We examined whether there is any difference between the migratory activity of AF derived from spontaneously hypertensive rat (SHR) and that from their normotensive counterpart Wistar-Kyoto rats (WKY). In addition, the role of osteopontin (OPN) in cell migration was also examined. Primary cultures of aortic adventitial fibroblasts were derived from SHR and age-matched WKY. Migration of fibroblasts was determined with the Transwell method. The mRNA expression level of OPN was measured by a real-time quantitative PCR. When compared with WKY-derived cells, migration of adventitial fibroblasts from SHR exhibited an increased response when stimulated by 10% serum (cell number per field 35.20+/-5.26 vs 22.2+/-3.27, p<0.05). Chemotaxis induced by 10 ng/ml bFGF showed a similar difference (cell number per field 30.23+/-4.54 vs 19.20+/-4.47, p<0.05). We also found that SHR-derived fibroblasts expressed a higher level of OPN mRNA than the cells from WKY (1863.23+/-43.91 vs 326.24+/-68.29, p<0.01). To verify if OPN is associated with the enhanced migratory ability in AF from SHR, we designed the antisense oligonucleotide of OPN. The results showed that the antisense OPN oligonucleotide significantly inhibited AF migration (cell number per field 38.60+/-5.98 vs 26.61+/-3.84, p<0.05), while sense and mismatch OPN oligonucleotide had no effect on cell migration. Therefore, the migration of adventitial fibroblasts appeared to be enhanced in cultures derived from SHR. OPN might be involved in the difference observed.
Animals ; Aorta ; cytology ; Cell Movement ; drug effects ; Cells, Cultured ; Fibroblasts ; cytology ; Hypertension ; physiopathology ; Male ; Osteopontin ; Phosphoproteins ; pharmacology ; Rats ; Rats, Inbred SHR ; Rats, Inbred WKY ; Sialoglycoproteins ; pharmacology

The purpose of this study was to clarify the characteristics of the pacemaker cells in the left ventricular outflow tract (aortic vestibule) and compare them with those of the cells in the sinoatrial node (SAN). By using conventional intracellular microelectrode technique to record their action potentials, some ionic channel blockers were used to observe their electrophysiological effects on the two types of pacemaker cells in the rabbit, especially on the ionic movement during phase 0 and phase 4. The results obtained are as follows. (1) Perfusion with 1 micromol/L verapamil (VER) resulted in a significant reduction in the amplitude of action potential (APA), maximal rate of depolarization (V(max)), absolute value of the maximal diastolic potential (MDP), velocity of diastolic depolarization (VDD) and rate of pacemaker firing (RPF), and also a prolongation of the 90% of the duration of action potential (APD(90)) in the pacemaker cells of the SAN and aortic vestibule (P<0.05). (2) Perfusion with 180 micromol/L nickel chloride (NiCl2) resulted in a decrease in VDD in the two types of the pacemaker cells (P<0.01). APA, V(max) and RPF fell notably, and the APD(90) prolonged in the sinoatrial node cells (P<0.05). (3) 2 mmol/L 4-aminopyridine (4-AP) led to a increase in VDD in both types of pacemaker cells (P<0.01). At the same time the absolute values of MDP, APA and V(max) decreased significantly, and APD(90) prolonged notably (P<0.05). During the perfusion, RPF in SAN increased markedly, while RPF in aortic vestibule exhibited no significant change. (4) 2 mmol/L cesium chloride (CsCl) led to a decrease in VDD and RPF in the two types of the pacemaker cells (P<0.05).These results suggested: (1) the ion currents in phase 0 and phase 4 of depolarization and repolarization of slow-response activity in aortic vestibule are similar to those in dominant pacemaker cells of sinoatrial node; (2) for the pacemaker cells in the left ventricular outflow tract, Ca(2+) current is the main depolarizing ion current of the phase 0, K(+) current is the main factor responsible for the repolarization. Attenuation of K(+) current is responsible for the phase 4 spontaneous depolarization. In addition, it seems that I(Ca-T), I(Ca-L) and I(f ) play some role in the pacemaker currents.
4-Aminopyridine ; pharmacology ; Action Potentials ; drug effects ; Animals ; Aorta, Thoracic ; cytology ; physiology ; Female ; Male ; Nickel ; pharmacology ; Periodicity ; Rabbits ; Sinoatrial Node ; cytology ; physiology ; Verapamil ; pharmacology