Pioglitazone modulates the proliferation and apoptosis of vascular smooth muscle cells via peroxisome proliferators-activated receptor-gamma
- Jing Wan†1Email author,
- Zhichao Xiao†2,
- Shengping Chao1,
- Shixi Xiong1,
- Xuedong Gan1,
- Xuguang Qiu2,
- Chang Xu2,
- Yexin Ma2 and
- Xin Tu3
© Wan et al.; licensee BioMed Central Ltd. 2014
Received: 19 January 2014
Accepted: 10 August 2014
Published: 19 September 2014
PPARγ is a member of the nuclear hormone receptor superfamily. It has been considered as a mediator regulating metabolism, anti-inflammation, and pro-proliferation in the Vascular Smooth Muscle Cells (VSMCs). Thiazolidinediones (TZDs), synthetic ligands of PPARγ, have anti-proliferative and pro-apoptotic effects on VSMCs, which prevent the formation and progression of atherosclerosis and restenosis following percutaneous coronary intervention (PCI). However, the underlying mechanism remains elusive. This present study therefore aimed to investigate the signaling pathway by which pioglitazone, one of TZDs, inhibits proliferation and induces apoptosis of VSMCs.
The effects of pioglitazone on VSMC proliferation and apoptosis were studied. Cell proliferation was determined using BrdU incorporation assay. Cell apoptosis was monitored with Hoechst and Annexin V staining. The expression of caspases and cyclins was determined using real-time PCR and Western blot.
Pioglitazone treatment and PPARγ overexpression inhibited proliferation and induced apoptosis of VSMCs, whereas blocking by antagonist or silencing by siRNA of PPARγ significantly attenuated pioglitazone’s effect. Furthermore, pioglitazone treatment or PPARγ overexpression increased caspase 3 and caspase 9 expression, and decreased the expression of cyclin B1 and cyclin D1 in VSMCs.
Pioglitazone inhibits VSMCs proliferation and promotes apoptosis of VSMCs through a PPARγ signaling pathway. Up-regulation of caspase 3 and down-regulation of cyclins mediates pioglitazone’s anti-proliferative and pro-apoptotic effects. Our results imply that pioglitazone prevents the VSMCs proliferation via modulation of caspase and cyclin signaling pathways in a PPARγ-dependent manner.
KeywordsPeroxisome proliferators-activated receptor gamma Thiazolidinedione Apoptosis Caspase Cyclins
Proliferation and apoptosis of the Vascular Smooth Muscle Cells (VSMCs) play a key role in the development and progression of the atherosclerosis and restenosis after percutaneous coronary intervention (PCI) [1, 2]. Several signaling pathways are involved in the progression of atherosclerosis and restenosis and the key players include peroxisome proliferators-activated receptor gamma (PPARγ) , platelet-derived growth factors (PDGF) , endothelin-1 (ET-1) , thrombin, fibroblast growth factor (FGF) . Activation and interplay of these molecules induce the proliferation and migration of VSMCs, leading to formation of artery plaque. Several drugs, such as pioglitazone, a synthetic ligand of PPARγ, have been developed to treat and prevent the proliferation of VSMCs by targeting individual factors of these pathways.
PPARγ is a member of the nuclear hormone receptor superfamily . It has been initially considered as a mediator regulating glucose and lipid metabolism. More recently, studies have revealed the presence of PPARγ in endothelial cells (ECs), VSMCs, macrophages and cardiomyocytes. PPARγ has multiple functions, including anti-inflammation and pro-proliferation in VSMCs . Apoptosis is an important contributor to the formation of atherosclerosis, especially in the process of restenosis after PCI. PPARγ has anti-apoptotic effect herein by modulation of caspase 3 .
Pioglitazone is commonly used as a primary anti-diabetic drug. Previous studies have shown that pioglitazone was able to inhibit the proliferation and induce apoptosis of VSMCs [10, 11]. However, the underlying mechanisms have not been well understood yet. Hence, the aim of present study was to determine if pioglitazone regulates cell cycle and caspase cascades, leading to an inhibition in VSMCs proliferation.
Materials and methods
Cell culture and in vitro cell treatment
Human coronary artery smooth muscle cells (Lonza, Basel Switzerland) were grown and maintained in SmGM-2 media (Lonza, Basel Switzerland) supplemented with 2% fetal calf serum, 10 ng/mL human epidermal growth factor, 1.0 mg/ml hydrocortisone, 12 mg/mL bovine brain extract, 50 mg/mL gentamicin, and 50 ng/mL amphotericin B at 37°C in 5% CO2 atmosphere. The purity of each VSMCs preparation in culture (>99%) was confirmed by immunocytochemistry for α-smooth muscle actin. VSMCs between passage 2 and 6 were used for following experiments. VSMCs (1 × 106) were treated for 24 h in medium containing vehicle (0.5% methyl cellulose), 10 uM pioglitazone or 1 uM GW9662, (Sigma). To over-express PPARγ-1 in VSMCs, cells were transduced with the recombinant adenovirus at titers of 100 MOI for 24 hours. Wild type PPARγ-1 adenovirus (Ad-wt-PPARγ) and mutation PPARγ-1 adenovirus were kind gifts from Dr. Qinglin Yang (Morehouse School of Medicine, Atlanta, USA). According to the principles of siRNA design and the PPARγ gene sequence (GenBank Accession No. NM_005037), the duplexes of specific siRNA sequences 5′-GTTCAAACACATCACCCCC-3′ was synthesized, non targeting siRNA: 5′-GCATATTGTCTATGACCAACT-3′.
Adenoviral transduction of VSMCs
The resultant recombinant virusmids were transfected into packaging cells HEK293 to generate recombinant adenoviruses. The primary crude lysates of the recombinant adenoviruses were prepared and purified by cesium chloride gradient ultracentrifugation as viral stocks and titrated using a standard plaque assay. VSMCs were seeded at a density of 2 × 105 in one 6-cm dish in antibiotic-free medium containing 10% serum before incubation with the transduction reagent Oligofectamine (Invitrogen Carlsbad, CA). One day later, cells were transduced with the recombinant adenovirus at titers of 100 MOI for 24 hours following the manufacturer’s protocols. For co-transduction studies, attractene (Qiagen) was employed as the transduction agent following the manufacturer’s recommendations, and non-targeting siRNA was used as experimental controls. During the final 24 hours of transfection, cells were treated with either vehicle (0.5% methyl cellulose) or pioglitazone (1 μM) .
BrdU cell proliferation assay
The cell proliferation assay was performed by measuring 5-Bromo-2′-deoxy-uridine (BrdU) (Roche Applied Science, USA) incorporation into the newly synthesized DNA of replicating cells. To determine cell proliferation, VSMCs were plated in 96-well plates and allowed to attach for 24 hours. Cells were then treated with 1 uM Pioglitazone, 10 uM GW9662 or transduced with the recombinant adenovirus for 24 hours. The cells were loaded with BrdU in the last 4 hours of treatment. BrdU incorporation was quantified by an immunofluorescence assay kit (Roche Applied Science, USA) following manufacturer’s instructions. Three fields were chosen randomly from various sections to ensure objectivity of sampling. Digital images were acquired using a confocal microscope. Each assay repeated three times. The total 100 cells from each field were counted, and BrdU positive cell and the ratio of BrdU positive cell versus 100 cells were calculated using a confocal microscope. Each assay repeated three times.
Apoptosis of VSMCs detected by Hoechst staining
To evaluate morphologic changes of apoptotic VSMCs, morphology and apoptosis assay were performed using the Hoechst staining as described previously . Briefly, cells were seeded on chamber slides, treated with 1 uM Pioglitazone, 10 uM GW9662 or transduced with the recombinant adenovirus for 24 h. Cells then were washed, fixed and stained with Hoechst 33258 (Sigma, St. Louis, MO). Dead cells and apoptotic bodies were identified by condensed or fragmented nuclei using a Nikon confocal microscope. The apoptotic scores were counted from five randomly selected fields by direct counting 500 cells in each sample using a blinded method . The percentage of apoptotic cells was calculated as the number of apoptotic cells divided by the number of total cells.
Measurement of apoptosis by flow cytometry
Apoptosis was measured using the FITC-Annexin V Apoptosis Detection kit (BD Bioscience, San Diego, CA) as described previously with modifications . Briefly, VSMCs were harvested, incubated and treated with 10 uM GW9662, 1 uM pioglitazone or transduced with the recombinant adenovirus for 24 h. After cell treatment, VSMCs were washed twice with cold PBS and resuspended in 1× binding buffer, (10 mM HEPES/NaOH, pH 7.4, 140 mM NaCl, 2.5 mM CaCl2) at a concentration of 1 × 106 cells/ml. Then 1 × 105 cells in 100 μl binding buffer were transferred to 5 ml tubes and stained with 5 μl of FITC-Annexin V and 5 μl propidium iodide (PI). The cells were gently mixed and incubated at room temperature for 15 min. After washing the cells with 1× binding buffer to remove the excess FITC-Annexin V and PI, the cells were analyzed on a FACScan flow cytometer, which the wavelength of excitation and emission were 488 nm and 525 nm, respecrively. The data were analyzed using CellQuest software.
Detection of active caspases 3/7, 8 and 9 in VSMCs
Caspases activities were measured using the Vybrant FAM caspase 3/7, 8 and 9 Assay Kit (Molecular Probes, Invitrogen) according to the manufacturer’s recommendations after the incubation of cells with pioglitazone (1uM), GW9662 (10uM), or transduced with the recombinant adenovirus for 24 h. The assay was performed on a fluorescent inhibitor of caspases (FLICA) methodology. The increase in the caspases activities was determined by comparing these results with the level of the untreated control. Samples analyzed on a FACScan flow cytometry with 488 nm excitation and green emission for the FLICA-stained cells.
After cell treatment, VSMCs were washed with phosphate-buffered saline (PBS) and lysed in RIPA buffer (Biotech, Shanghai, China). After one freeze/thaw cycle, lysates were centrifuged. Protein concentration was determined by a BCA protein assay (Biotech, Shanghai, China) using bovine serum albumin as the standard. A quantity amounting to 10 μg of protein sample was subjected to SDS-polyacrylamide gel electrophoresis. Proteins were then transferred to an ECL nitrocellulose membrane (Millipore). Incubating the membrane in Superblock (Pierce) for 1 h blocked nonspecific binding. Membranes were then incubated overnight at 4°C in primary antibodies, PPARγ1, Cyclin D1, Cyclin B1/cdc2 and β-actin (AbCam: ab8924, ab95281, ab7959, ab1801). All primary antibodies dilution was 1:1000 in each reaction. The blots were washed three times with TBST buffer and then incubated for 1 h at room temperature with anti-rabbit secondary antibody conjugated with horseradish peroxidase. Western blot analysis was conducted according to standard procedures using Supersignal chemiluminescence detection substrate (Pierce).
Real time RT-PCR
Total RNA was extracted from VSMCs using TRIZOL reagent (Invitrogen, Carlsbad, CA, USA). cDNA was synthesized from 0.5 μg of total RNA with superscriptor reverse transcriptase (Invitrogen, Carlsbad, CA, USA). The following specific primers were used: PPARγ-forward: 5′-GCCCTTTACCACAGTTGATTTCTCCA-3′; PPARγ-reverse: 5′-TATCCCCACAGACTCGGCACTCA-3′; Cyclin B1/cdc2-forward: 5′-CTGGGTCGGGAAGTCACTGGAAAC-3′; Cyclin B1/cdc2-reverse: 5′-GCAGCATCTTCTTGGGCACACA-3′; Cyclin D1-forward: 5′-AGGCGGAGGAGAACAAACAGATCA-3′; Cyclin D1-reverse: 5′-AGAGGAAGCGTGTGAGGCGGTAGTA-3′; β-actin-forward: 5′-TTTTGTGCCTTGATAGTTCGC-3′; β-actin- reverse: 5′-GAGTCCTTCTGACCCATACCC-3′. The real-time PCR analysis was performed using SyBR-Green mix (Applied Biosystems, Carlsbad, CA) on a 7500 Real Time PCR station (Applied Biosystems). The results for real-time PCR were calculated as ratio target gene expression (experimental/ control) and were expressed as fold change.
SPSS 11.0 software was used to for data analysis. Data were presented as mean ± SEM. Student’s t-test was employed to assess the statistical significance. P < 0.05 was regarded as significant.
Manipulation of PPARγ expression in VSMCs
Pioglitazone inhibits VSMCs proliferation through PPARγ signaling pathway
We next determined if PPARγ pathway mediates pioglitazone’s anti-proliferative effect. VSMCs were treated with GW9662, a potent antagonist of PPARγ. GW9662 treatment significantly enhanced VSMCs proliferation (0.248 ± 0.054 vs. 0.175 ± 0.031, P < 0.05) (Figure 2). Furthermore, PPARγ silenced VSMCs were treated with pioglitazone. Interestingly, PPARγ silencing by siRNA in VSMCs totally abolished the inhibitory effects of PIO (0.279 ± 0.009 vs. 0.051 ± 0.01, P < 0.001) (Figure 2). Our results indicate that anti-proliferative effect of pioglitazone is mediated by PPARγ signaling pathway.
Pioglitazone induced apoptosis in VSMCs
Pioglitazone treatment activates caspase3/7 and 8
Effect of pioglitazone on cyclins in VSMCs
The restenosis after PCI has become one of the most concerned issues worldwide . The proliferation and apoptosis of VSMCs play critical roles in this pathologic process . Thus, many therapeutic treatments focused on preventing VSMC proliferation and inducing apoptosis in VSMCs. TZD is one of the most well studied agents. TZDs are synthetic ligands of PPARγ, which is a member of the nuclear hormone receptor super-family. TZDs are primarily used as anti-diabetes drugs. TZD has also been indicated to have an anti-proliferative function in rat renal arteriolar smooth muscle cells . Recently, given their anti-proliferative and pro-apoptotic effect, TZDs have been considered as novel drugs to prevent or even reverse the formation of atherosclerosis and post-PCI restenosis. Importantly, TZDs do not increase the risk of overall cardiovascular morbidity or mortality in comparison with standard glucose-lowering drugs [18, 19], although there was the controversy that TZDs might potentially lead to serious adverse cardiovascular effects, such as heart failure after treatment with rosiglitazone for type 2 diabetes [20–22] . However, the mechanisms by which TZDs regulate VSMC proliferation have not been determined.
Previous studies have shown that TZDs suppress the expression of inflammatory molecules, including TNF (tumor necrosis factor)-α, MCP (monocyte chemotactic protein)-1, IL-1β and IL-6 in VSMCs [23, 24]. Moreover, recent studies have revealed that c-fos was involved in PPARγ agonists- induced growth suppression in VSMCs, and TZDs inhibited the expression of c-fos via the blockade of MAPK pathway . Furthermore, Eukaryotic initiation factor 4E-binding protein (4EBP) and Src homology 2–containing inositol phosphatase 2 (SHIP2) mediate the inhibitory effects of TZD on cell growth . Finally, it has been shown that TZDs prevent G1/S phase transition in PDGF or insulin stimulated VSMCs, suggesting that TZDs can induce cell cycle arrest .
It has been known that TZDs have anti-proliferative effect in different cell types via PI3-Kinase pathway . However, whether this effect is PPARγ-dependent remains to be clarified [29, 30]. The effects of PPARγ in the vascular cells indicate its beneficial function in vascular disorders including hypertension and atherosclerosis . Goetze group  has shown that troglitazone inhibited insulin-induced mitogenic signaling through a PPARγ-mediated inhibition of ERK-dependent phosphorylation and activation of nuclear transcription factors. However, this group revealed that TZDs activated MEK/ERK pathway through PI3-kinase and promoted c-fos mRNA expression and DNA synthesis, a process independent of PPARγ pathway . Cersosimo group suggested pioglitazone preserved Akt phosphorylation and attenuates MAPK signaling in insulin-stimulated VSMCs, and may play a role in arterial smooth muscle cells migration, proliferation, and inflammation in conditions of acute hyperinsulinemia . In our study, we found that pioglitazone treatment and PPARγ overexpression inhibited VSMC proliferation. Whereas silencing PPARγ with siRNA attenuated the inhibitory effects. These results clearly indicate that the PPARγ signaling pathway is involved in anti-proliferative effect of pioglitazone. Pioglitazone is already shown to inhibit in-stent neointimal formation in humans .
Cyclins play critical roles in cell cycle regulation, especially cyclin B1 and cyclin D1 . PPARγ ligands inhibited G1 to S transition by inhibiting the expression of minichromosome maintenance (MCM) gene, one of the downstream effector factors of pRB/E2F pathway . Stimulation of PPARγ induced the arrest of cell cycle, accompanied by the down-regulation of cyclin D and cyclin B in VSMCs [36–39]. To determine the detailed mechanisms by which pioglitazone regulates VSMC proliferation, in this study the mRNA and protein levels of cyclin B1 and cyclin D1 were tested. We found that pioglitazone treatment and PAPRγ overexpression significantly down-regulated both mRNA and protein levels of cyclin B1 and cyclin D1. These results suggest that the beneficial functions of the TZDs are mediated, at least in part, by regulating the expression and transcription of cyclin B and cyclin D.
Aside from the impact of proliferation of VSMCs on the formation of atherosclerosis and restenosis, the apoptosis of VSMC also plays an important role in these processes. The pro-apoptotic effect of PPARγ in VSMCs has been reported. Bruemmer’s group revealed that the Oct-1 protein was regulated by the TZDs, which in turn induced overexpression of the growth arrest and DNA damage inducible protein 45(GADD45) gene, ultimately leading to the apoptosis of VSMCs . Other groups have shown that pioglitazone also activated TGF (Transforming Growth Factor)-β-smad2-GADD45 pathway [41, 42]. Pioglitazone induced apoptosis in VSMCs through Smad2 phosphorylation . Caspases are a family of cysteine proteases that play important roles in apoptosis. Caspase 8 and caspase 9 are the two initiative caspases involved in both extrinsic and intrinsic apoptotic pathways, while caspase 3 is a terminal effector caspase . Bruedigam group showed that rosiglitazone stimulated mineralization by induction of caspase-dependent apoptosis . Here, we found that pioglitazone treatment and PPARγ overexpression induced activation of caspase 8 and caspase 3/7, indicating that pioglitazone induces VSMC apoptosis through the extrinsic caspase pathway.
In summary, our study shows for the first time the regulatory pathways involved in the anti-proliferative effect of pioglitazone in VSMCs. Pioglitazone treatment inhibits proliferation of the VSMCs and induces VSMC apoptosis in a PPARγ-dependent pathway. Down-regulation of cyclin B1 and cyclin D1 and activation of caspase 8 and caspase 3/7 may be one of the mechanisms by which pioglitazone inhibits VSMC proliferation.
Peroxisome proliferators-activated receptor gamma
Vascular smooth muscle cells
Percutaneous coronary intervention
Coronary artery disease
Platelet-derived growth factors
Fibroblast growth factor
Tumor necrosis factor
Monocyte chemotactic protein
Eukaryotic initiation factor 4E-binding protein
Src homology 2–containing inositol phosphatase 2
Growth Arrest and DNA Damage
Transforming growth factor
This paper was supported by the National Natural Science Foundation of China, it is youth fund, the number is 81200220.
- Zwolak RM, Adams MC, Clowes AW: Kinetics of vein graft hyperplasia: association with tangential stress. J Vasc Surg. 1987, 5 (1): 126-136. 10.1016/0741-5214(87)90203-5.View ArticlePubMedGoogle Scholar
- Ross R: Cell biology of atherosclerosis. Annu Rev Physiol. 1995, 57: 791-804. 10.1146/annurev.ph.57.030195.004043.View ArticlePubMedGoogle Scholar
- Dannoura A, Giraldo A, Pereira I, Gibbins JM, Dash PR, Bicknell KA, Brooks G: Ibuprofen inhibits migration and proliferation of human coronary artery smooth muscle cells by inducing a differentiated phenotype: role of peroxisome proliferator-activated receptor γ. J Pharm Pharmacol. 2014, 10 (112): 2301-2314.Google Scholar
- Ho HC, Chang HC, Ting CT, Kuo CY, Yang VC: Caffeic acid phenethyl ester inhibits proliferation and migration, and induces apoptosis in platelet-derived growth factor-BB-stimulated human coronary smooth muscle cells. J Vasc Res. 2012, 49 (1): 24-32. 10.1159/000329819.View ArticlePubMedGoogle Scholar
- Kitada K, Ohkita M: Matsumura YPathological importance of the endothelin-1/ET (B) receptor system on vascular diseases. Cardiol Res Pract. 2012, 1212: 731-738.Google Scholar
- Brisset AC, Hao H, Camenzind E, Bacchetta M, Geinoz A, Sanchez JC, Chaponnier C, Gabbiani G, Bochaton-Piallat ML: Intimal smooth muscle cells of porcine and human coronary artery express S100A4, a marker of the rhomboid phenotype in vitro. Circ Res. 2007, 100 (7): 1055-1062. 10.1161/01.RES.0000262654.84810.6c.View ArticlePubMedGoogle Scholar
- Willson TM, Lambert MH, Kliewer SA: Peroxisome proliferator-activated receptor gamma and metabolic disease. Annu Rev Biochem. 2001, 70: 341-367. 10.1146/annurev.biochem.70.1.341.View ArticlePubMedGoogle Scholar
- Rangwala SM, Lazar MA: Peroxisome proliferator-activated receptor gamma in diabetes and metabolism. Trends Pharmacol Sci. 2004, 25 (6): 331-336. 10.1016/j.tips.2004.03.012.View ArticlePubMedGoogle Scholar
- Xiao Y, Yuan T, Yao W, Liao K: 3 T3-L1 adipocyte apoptosis induced by thiazolidinediones is peroxisome proliferator-activated receptor-gamma-dependent and mediated by the caspase-3-dependent apoptotic pathway. FEBS J. 2010, 277 (3): 687-696. 10.1111/j.1742-4658.2009.07514.x.View ArticlePubMedGoogle Scholar
- Yuan X, Zhang Z, Gong K, Zhao P, Qin J, Liu N: Inhibition of reactive oxygen species/extracellular signal-regulated kinases pathway by pioglitazone attenuates advanced glycation end products-induced proliferation of vascular smooth muscle cells in rats. Biol Pharm Bull. 2011, 34 (5): 618-623. 10.1248/bpb.34.618.View ArticlePubMedGoogle Scholar
- Ruiz E, Redondo S, Gordillo-Moscoso A, Tejerina T: Pioglitazone induces apoptosis in human vascular smooth muscle cells from diabetic patients involving the transforming growth factor-beta/activin receptor-like kinase-4/5/7/Smad2 signaling pathway. J Pharmacol Exp Ther. 2007, 321 (2): 431-438. 10.1124/jpet.106.114934.View ArticlePubMedGoogle Scholar
- Tashiro K, Kawabata K, Sakurai H, Kurachi S, Sakurai F, Yamanishi K, Mizuguchi H: Efficient adenovirus vector-mediated PPAR gamma gene transfer into mouse embryoid bodies promotes adipocyte differentiation. J Gene Med. 2008, 10 (5): 498-507. 10.1002/jgm.1171.View ArticlePubMedGoogle Scholar
- Akimoto T, Kusano E, Inaba T, Iimura O, Takahashi H, Ikeda H, Ito C, Ando Y, Ozawa K, Asano Y: Erythropoietin regulates vascular smooth muscle cell apoptosis by a phosphatidylinositol 3 kinase-dependent pathway. Kidney Int. 2000, 58 (1): 269-282. 10.1046/j.1523-1755.2000.00162.x.View ArticlePubMedGoogle Scholar
- Tsao PN, Su YN, Li H, Huang PH, Chien CT, Lai YL, Lee CN, Chen CA, Cheng WF, Wei SC: Overexpression of placenta growth factor contributes to the pathogenesis of pulmonary emphysema. Am J Respir Crit Care Med. 2004, 169 (4): 505-511. 10.1164/rccm.200306-774OC.View ArticlePubMedGoogle Scholar
- American Heart Association: Heart Disease and Stroke Statistics—2004 Update. 2004, Dallas, TX: American Heart AssociationGoogle Scholar
- Karsch KR, Haase KK, Wehrmann M, Hassenstein S, Hanke H: Smooth muscle cell proliferation and restenosis after stand alone coronary excimer laser angioplasty. J Am Coll Cardiol. 1991, 17: 991-994. 10.1016/0735-1097(91)90886-E.View ArticlePubMedGoogle Scholar
- Dubey RK, Zhang HY, Reddy SR, Boegehold MA, Kotchen TA: Pioglitazone attenuates hypertension and inhibits growth of renal arteriolar smooth muscle in rats. Am J Physiol. 1993, 265 (4): 726-732.Google Scholar
- Home PD, Phil D, Pocock SJ, Henning B-N, Ramón G, Markolf H, Jones NP, Michel K, John JV MM: Rosiglitazone Evaluated for Cardiovascular Outcomes — An Interim Analysis. N Engl J Med. 2007, 357: 28-38. 10.1056/NEJMoa073394.View ArticlePubMedGoogle Scholar
- Lago RM, Singh PP, Nesto RW: Congestive heart failure and cardiovascular death in patients with prediabetes and type 2 diabetes given thiazolidinediones: a meta-analysis of randomised clinical trials. N Engl J Med. 2007, 356: 2457-2471. 10.1056/NEJMoa072761.View ArticleGoogle Scholar
- Home PD, Pocock SJ, Beck-Nielsen H, Curtis PS, Gomis R, Hanefeld M, Jones NP, Komajda M, McMurray JJ: Rosiglitazone evaluated for cardiovascular outcomes in oral agentcombination therapy for type 2 diabetes (RECORD): a multicentre, randomised, open-label trial.; RECORD Study Team. Lancet. 2009, 373 (9681): 2125-2135. 10.1016/S0140-6736(09)60953-3.View ArticlePubMedGoogle Scholar
- Nissen SE, Kathy W: Effect of rosiglitazone on the risk of myocardial infarction and death from cardiovascular causes. N Engl J Med. 2007, 356 (24): 2457-2471. 10.1056/NEJMoa072761.View ArticlePubMedGoogle Scholar
- Sonal S, Loke YK, Furberg CD: Long-term risk of cardiovascular events with rosiglitazone, a meta-analysis. JAMA. 2007, 298 (10): 1189-1195. 10.1001/jama.298.10.1189.View ArticleGoogle Scholar
- Park KG, Lee KM, Chang YC, Magae J, Ando K, Kim KB, Kim YN, Kim HS, Park JY, Lee KU, Lee IK: The ascochlorin derivative, AS-6, inhibits TNF-alpha-induced adhesion molecule and chemokine expression in rat vascular smooth muscle cells. Life Sci. 2006, 80 (2): 120-126. 10.1016/j.lfs.2006.08.030.View ArticlePubMedGoogle Scholar
- Takata Y, Kitami Y, Yang ZH, Nakamura M, Okura T, Hiwada K: Vascular inflammation is negatively autoregulated by interaction between CCAAT/enhancer-binding protein-delta and peroxisome proliferator-activated receptor-gamma. Circ Res. 2002, 91 (5): 427-433. 10.1161/01.RES.0000031271.20771.4F.View ArticlePubMedGoogle Scholar
- Law RE, Meehan WP, Xi XP, Graf K, Wuthrich DA, Coats W, Faxon D, Hsueh WA: Troglitazone inhibits vascular smooth muscle cell growth and intimal hyperplasia. J Clin Invest. 1996, 98 (8): 1897-1905. 10.1172/JCI118991.PubMed CentralView ArticlePubMedGoogle Scholar
- Benkirane K, Amiri F, Diep QN, El Mabrouk M, Schiffrin EL: PPAR-gamma inhibits ANG II-induced cell growth via SHIP2 and 4E-BP1. Am J Physiol Heart Circ Physiol. 2006, 290 (1): H390-H397.View ArticlePubMedGoogle Scholar
- Wakino S, Kintscher U, Kim S, Yin F, Hsueh WA, Law RE: Peroxisome proliferator-activated receptor gamma ligands inhibit retinoblastoma phosphorylation and G1 S transition in vascular smooth muscle cells. J Biol Chem. 2000, 275 (29): 22435-22441. 10.1074/jbc.M910452199.View ArticlePubMedGoogle Scholar
- Mishra P, Paramasivam SK, Thylur RP, Rana A, Rana B: Peroxisome proliferator-activated receptor gamma ligand-mediated apoptosis of hepatocellular carcinoma cells depends upon modulation of PI3Kinase pathway independent of Akt. J Mol Signal. 2010, 5: 20-10.1186/1750-2187-5-20.PubMed CentralView ArticlePubMedGoogle Scholar
- Goetze S, Kim S, Xi XP, Graf K, Yang DC, Fleck E, Meehan WP, Hsueh WA, Law RE: Troglitazone inhibits mitogenic signaling by insulin in vascular smooth muscle cells. J Cardiovasc Pharmacol. 2000, 35 (5): 749-757. 10.1097/00005344-200005000-00011.View ArticlePubMedGoogle Scholar
- Takeda K, Ichiki T, Tokunou T, Iino N, Takeshita A: 15-Deoxy-delta 12,14-prostaglandin J2 and thiazolidinediones activate the MEK/ERK pathway through phosphatidylinositol 3-kinase in vascular smooth muscle cells. J Biol Chem. 2001, 276 (52): 48950-48955. 10.1074/jbc.M108722200.View ArticlePubMedGoogle Scholar
- Duan SZ, Usher MG, Mortensen RM: Peroxisome proliferator-activated receptor-gamma-mediated effects in the vasculature. Circ Res. 2008, 102 (3): 283-294. 10.1161/CIRCRESAHA.107.164384.View ArticlePubMedGoogle Scholar
- Cersosimo E, Xu X, Musi N: Potential role of insulin signaling on vascular smooth muscle cell migration, proliferation, and inflammation pathways. Am J Physiol Cell Physiol. 2012, 302 (4): 652-657. 10.1152/ajpcell.00022.2011.View ArticleGoogle Scholar
- Takagi T, Okura H, Kobayashi Y, Kataoka T, Taguchi H, Toda I, Tamita K, Yamamuro A, Sakanoue Y, Ito A, Yanagi S, Shimeno K, Waseda K, Yamasaki M, Fitzgerald PJ, Ikeno F, Honda Y, Yoshiyama M, Yoshikawa J: A prospective, multicenter, randomized trial to a ssess efficacy of pioglitazone on in-stent neointimal suppression in type 2 diabetes: POPPS (Prevention of In-Stent Neointimal Proliferation by Pioglitazone Study). JACC Cardiovasc Interv. 2009, 2 (6): 524-531. 10.1016/j.jcin.2009.04.007.View ArticlePubMedGoogle Scholar
- Morgan DO: Principles of CDK regulation. Nature. 1995, 374 (6518): 131-134. 10.1038/374131a0.View ArticlePubMedGoogle Scholar
- Florence G, Dennis B: Transcriptional control of vascular smooth muscle cell proliferation by peroxisome proliferator-activated receptor-γ: therapeutic implications for cardiovascular diseases. PPAR Res. 2008, 2008: 429123-Google Scholar
- Santucci MA, Mercatali L, Brusa G, Pattacini L, Barbieri E, Perocco P: Cell-cycle deregulation in BALB/c 3T3 cells transformed by 1,2-dibromoethane and folpet pesticides. Environ Mol Mutagen. 2003, 41 (5): 315-321. 10.1002/em.10162.View ArticlePubMedGoogle Scholar
- Kim EJ, Park KS, Chung SY, Sheen YY, Moon DC, Song YS, Kim KS, Song S, Yun YP, Lee MK, Oh KW, Yoon DY, Hong JT: Peroxisome proliferator-activated receptor-gamma activator 15-deoxy-Delta12,14-prostaglandin J2 inhibits neuroblastoma cell growth through induction of apoptosis: association with extracellular signal-regulated kinase signal pathway. J Pharmacol Exp Ther. 2003, 307 (2): 505-517. 10.1124/jpet.103.053876.View ArticlePubMedGoogle Scholar
- Strakova N, Ehrmann J, Dzubak P, Bouchal J, Kolar Z: The synthetic ligand of peroxisome proliferator-activated receptor-gamma ciglitazone affects human glioblastoma cell lines. J Pharmacol Exp Ther. 2004, 309 (3): 1239-1247. 10.1124/jpet.103.063438.View ArticlePubMedGoogle Scholar
- Jeon EM, Choi HC, Lee KY, Chang KC, Kang YJ: Hemin inhibits hypertensive rat vascular smooth muscle cell proliferation through regulation of cyclin D and p21. Arch Pharm Res. 2009, 32 (3): 375-382. 10.1007/s12272-009-1310-2.View ArticlePubMedGoogle Scholar
- Bruemmer D, Yin F, Liu J, Berger JP, Sakai T, Blaschke F, Fleck E, Van Herle AJ, Forman BM, Law RE: Regulation of the growth arrest and DNA damage-inducible gene 45 (GADD45) by peroxisome proliferator-activated receptor gamma in vascular smooth muscle cells. Circ Res. 2003, 93 (4): e38-e47. 10.1161/01.RES.0000088344.15288.E6.View ArticlePubMedGoogle Scholar
- Redondo S, Ruiz E, Santos-Gallego CG, Padilla E, Tejerina T: Pioglitazone induces vascular smooth muscle cell apoptosis through a peroxisome proliferator-activated receptor-gamma, transforming growth factor-beta1, and a Smad2-dependent mechanism. Diabetes. 2005, 54 (3): 811-817. 10.2337/diabetes.54.3.811.View ArticlePubMedGoogle Scholar
- Yoo J, Ghiassi M, Jirmanova L, Balliet AG, Hoffman B, Fornace AJ, Liebermann DA, Bottinger EP, Roberts AB: Transforming growth factor-beta-induced apoptosis is mediated by Smad-dependent expression of GADD45b through p38 activation. J Biol Chem. 2003, 278 (44): 43001-43007. 10.1074/jbc.M307869200.View ArticlePubMedGoogle Scholar
- Gustafsson AB, Gottlieb RA: Bcl-2 family members and apoptosis, taken to heart. Am J Physiol Cell Physiol. 2007, 292 (1): C45-C51.View ArticlePubMedGoogle Scholar
- Bruedigam C, Eijken M, Koedam M, Chiba H, Van Leeuwen JP: Opposing actions of rosiglitazone and resveratrol on mineralization in human vascular smooth muscle cells. J Mol Cell Cardiol. 2011, 51 (5): 862-871. 10.1016/j.yjmcc.2011.07.020.View ArticlePubMedGoogle Scholar
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