Different Concentrations Of Rosiglitazone Research Articles

Protective effect of rosiglitazone on microscopic and oxidative stress parameters of ram sperm after freeze-thawing

The purpose of this study was to investigate the effects of rosiglitazone on ram semen after cryopreservation on the quality of thawed sperm. Sperm motility, membrane functionality, viability, total abnormality, acrosome membrane integrity, mitochondrial activity, reactive oxygen species production, ATP content and apoptotic features were assessed after thawing. Rosiglitazone at concentration of 60 µM resulted in the highest (P < 0.05) total motility, progressive motility and straight-line velocity. The percentages of average path velocity and curvilinear velocity were greater in the 60 µM group. Different concentrations of rosiglitazone did not have significant effects on amplitude of the lateral head displacement, linearity and straightness. The highest amounts of membrane functionality and mitochondrial activity after freeze-thawing were observed in groups containing 60 µM. By increasing the rosiglitazone level to 80 µM, no positive effect was observed in most of the evaluated parameters. The lowest ROS concentration was recorded in 60 µM rosiglitazone group (P < 0.05). The group containing 60 µM rosiglitazone also produced the lowest significant percentage of apoptosis-like changes and dead sperm. A greater (P < 0.05) percentage of acrosome integrity in frozen-thawed spermatozoa was observed in the 60 µM rosiglitazone group. There was no significant difference between 40 and 60 µM rosiglitazone in intact acrosome of ram thawed semen. The result showed that supplementation in ram semen extender with rosiglitazone had a positive role in the regulation of ram sperm motility and had strong protective effect on the sperm membrane and acrosome integrity.

PPARγ-Independent Side Effects of Thiazolidinediones on Mitochondrial Redox State in Rat Isolated Hearts.

The effect of anti-diabetic thiazolidinediones (TZDs) on contributing to heart failure and cardiac ischemia/reperfusion (IR) injury is controversial. In this study we investigated the effect of select TZDs on myocardial and mitochondrial function in Brown Norway rat isolated hearts. In a first set of experiments, the TZD rosiglitazone was given acutely before global myocardial IR, and pre- and post-IR function and infarct size were assessed. In a second set of experiments, different concentrations of rosiglitazone and pioglitazone were administered in the presence or absence of the specific PPARγ antagonist GW9662, and their effects on the mitochondrial redox state were measured by online NADH and FAD autofluorescence. The administration of rosiglitazone did not significantly affect myocardial function except for transiently increasing coronary flow, but it increased IR injury compared to the control hearts. Both TZDs resulted in dose-dependent, reversible increases in mitochondrial oxidation which was not attenuated by GW9662. Taken together, these data suggest that TZDs cause excessive mitochondrial uncoupling by a PPARγ-independent mechanism. Acute rosiglitazone administration before IR was associated with enhanced cardiac injury. If translated clinically, susceptible patients on PPARγ agonists may experience enhanced myocardial IR injury by mitochondrial dysfunction.

Protective influence of rosiglitazone against time-dependent deterioration of boar spermatozoa preserved at 17°C.

Spermatozoa are highly specialized cells, and energy metabolism plays an important role in modulating sperm viability and function. Rosiglitazone is an antidiabetic drug in the thiazolidinedione class that regulates metabolic flexibility and glucose uptake in various cell types, but its effects on boar sperm metabolism are unknown. In this study, we investigated the potential effect of rosiglitazone against time-dependent deterioration of boar spermatozoa during liquid preservation at 17°C. Freshly ejaculated semen was diluted with Beltsville Thawing Solution (BTS) containing different concentrations of rosiglitazone, and the motility, membrane and acrosome integrity of sperm were detected. Besides, we measured glucose uptake capacity, l-lactate production level, mitochondrial membrane potential, adenosine triphosphate (ATP) content and mitochondrial reactive oxygen species (mROS) production of sperm after boar semen had been incubated with or without rosiglitazone, iodoacetate (glycolysis inhibitor) and rotenone (electron transport chain inhibitor) for 5days. The addition of rosiglitazone significantly enhanced sperm quality and had a strong protective effect on the sperm membrane and acrosome integrity during storage. BTS containing 50μM rosiglitazone maintained the total motility of liquid-preserved sperm above 60% for 7days. Rosiglitazone improved sperm quality by regulating energy metabolism manner of preserved sperm, protected the sperm mitochondrial membrane potential, enhanced sperm ATP production and in the meanwhile reduced mROS through enhancing glycolysis but not oxidative phosphorylation. The data suggested the practical feasibility of using rosiglitazone for improving boar spermatozoa quality during semen preservation.

Suppression of multidrug resistance by rosiglitazone treatment in human ovarian cancer cells through downregulation of FZD1 and MDR1 genes.

Multidrug resistance (MDR) is a major obstacle in the successful treatment of ovarian cancer. One of the most common causes of MDR is overexpression of P-glycoprotein (P-gp), encoded by the MDR1 gene. The MDR1 gene is a direct target of the Wnt/β-catenin signaling pathway, which plays an important role in ovarian cancer. Peroxisome proliferator-activated receptor γ (PPARγ) ligands have been found to protect against development of cancer through the Wnt/β-catenin pathway. To investigate the effect of PPARγ ligands on MDR1/P-gp expression, we treated a MDR ovarian cancer cell subline, A2780/Taxol, with different concentrations of rosiglitazone (Rosi), a member of the synthetic PPARγ ligands. Rosi downregulated FZD1 and MDR1/P-gp expression in a concentration-dependent manner. In addition, nuclear β-catenin levels and its transcriptional activity decreased significantly. In conclusion, Rosi may reverse MDR of ovarian cancer cells by downregulating the Wnt/β-catenin pathway with the suppression of FZD1.

Rosiglitazone suppresses angiogenesis in multiple myeloma via downregulation of hypoxia-inducible factor-1α and insulin-like growth factor-1 mRNA expression.

Rosiglitazone (RGZ) is a thiazolidinedione ligand of peroxisome proliferator-activated receptor-γ. Our previous studies have confirmed that RGZ possesses antitumoral properties. Bone marrow angiogenesis exhibits an important role in multiple myeloma (MM), and angiogenesis often correlates with the prognosis and disease burden of MM. However, to the best of our knowledge, inhibition of angiopoiesis by RGZ in MM has not yet been reported. The present study aimed to investigate whether RGZ prevents angiogenesis and the possible underlying mechanism of this effect in MM. RPMI‑8226 cells, primary myeloma cells from patients with MM or mononuclear cells from healthy patients were treated with different concentrations of RGZ, and various biological responses were detected using MTT, reverse transcription-polymerase chain reaction and western blot assays. The expression levels of hypoxia-inducible transcription factor‑1α (HIF1α) and insulin-like growth factor‑1 (IGF1) were significantly increased in the RPMI-8226 cells and the primary myeloma cells from the patients with MM compared with those in the mononuclear cells from the healthy patients. The results also showed that RGZ was able to inhibit proliferation and reduce viability of RPMI-8226 cells in a concentration-and time-dependent manner. RGZ was able to concentration‑dependently inhibit the expression of HIF1α and IGF1 mRNA in RPMI-8226 and primary myeloma cells from patients with MM. RGZ also inhibited the expression of pAKT and downregulated the expression levels of phosphorylated extracellular signal-regulated kinase (ERK) in RPMI-8226 cells. The results suggested that RGZ inhibits the angiopoiesis of tumors by interfering with the phosphatidylinositol 3-kinase/AKT and ERK signaling pathways.

Effects of rosiglitazone on expression of matrix metalloproteinase-2 and matrix metalloproteinase-9 in hepatic stellate cells

Objective To investigate the effects of rosiglitazone,a ligand of peroxisome proliferators activated receptor gamma (PPAR-γ),on the expression of matrix metalloproteinase (MMP)-2 and MMP-9 in hepatic stellate cells (HSCs).Methods HSCs were cultured in medium containing different concentrations of rosiglitazone (5,10,15,20 μmol/L respectively),and harvested at 24 h.The expression of MMP-2 and MMP-9 was detected by using reverse transcription polymerase chain reaction.Results The MMP-2 expression in HSCs cultured with different concentrations of rosiglitazone (5,10,15,20 μmol/L)was 0.5708 ±0.0609,0.8900 ±0.0823,1.1348 ±0.1205 and 1.4490 ±0.0832 respectively,and it in control group was 0.3237 ± 0.0796.The MMP-9 expression in HSCs cultured with different concentrations of rosiglitazone (5,10,15,20 μmol/L) was 0.5487 ±0.0770,0.7554 ±0.0510,0.9497 ±0.0451 and 1.1088 ±0.0777 respectively,and it in control group was 0.3220 ±0.0592.Conclusion PPAR-γ ligand rosiglitazone may up-regulate the expression of MMP-2 and MMP-9 in HSCs dose-dependently to some extent. Key words: Hepatic stellate cell; Peroxisome proliferators activated receptor gamma; Rosiglitazone ; Matrix metalloproteinase

Effects of rosiglitazone on expression of type I collagen and type III collagen in hepatic stellate cells

Objective To investigate the effects of rosiglitazone,a ligand of peroxisome proliferators activated receptor gamma (PPARγ),on the expression of type Ⅰ collagen (COL Ⅰ) and type Ⅲ collagen (COL Ⅲ) in hepatic stellate cells (HSCs).Methods HSCs were cultured in medium containing different concentrations of rosiglitazone (5,10,15,20 μmol/L respectively),and harvested at 24 h.The expression of COL Ⅰ and COLⅢ was detected by using reverse transcription polymerase chain reaction.Results The COL Ⅰ expression of HSCs cultured with different concentrations of rosiglitazone (5,10,15,20 μmoL/L) was 2.9755 ± 0.0853,1.9866 ± 0.0938,1.4935 ± 0.1078 and 0.9603 ± 0.1365 respectively,and it in control group was 3.4802 ±0.1331.The COLⅢ gene expression in HSCs cultured with different concentrations of rosiglitazone (5,10,15,20 μ mol/L) was 3.6207 ± 0.0461,2.6150 ±0.0793,2.0051 ± 0.0830 and 1.4175 ± 0.0862 respectively,and it in control group was 4.2714 ±0.4652.Conclusion PPARγ ligand rosiglitazone may down-regulate the gene expression of COL Ⅰ and COLll in HSCs dose-dependently to some extent. Key words: Hepatic stellate cell; Peroxisome proliferators activated receptor gamma; Rosiglitazone; Type Ⅰ collagen ; Type Ⅲ collagen

Rosiglitazone attenuates activation of human Tenon’s fibroblasts induced by transforming growth factor -β1

To investigate the influence of rosiglitazone on activation of human Tenon's fibroblasts (HTFs) and to access the possible mechanism. Cultured human Tenon's fibroblasts were pretreated in two different concentrations of rosiglitazone (5μmol/l and 10μmol/l) before being stimulated with 5ng/ml transforming growth factor β1 (TGF-β1). The viability and proliferation of cells were accessed by cell count kit-8 assay; Cell migration was examined by the wound closure assay; Alpha smooth muscle actin (α-SMA), connective tissue growth factor (CTGF) and type I collagen (COL I) transcription were detected by RT-qPCR; The expression and localization of α-SMA protein were examined by Western-blot analysis and Immunofluorescence staining; Western-blot analysis was also used to check the expression of CTGF, COL I peroxisome proliferator-activated receptor gamma (PPAR-γ), and phosphorylation of the signaling protein Smad2/3 Rosiglitazone is able to attenuate the up-regulation of α-SMA, CTGF, and COL I transcription, as well as affect protein expression, proliferation, and migration of cells; rosiglitazone also can increase PPAR-γ expression and attenuate Smad2/3 phosphorylation. Rosiglitazone can effectively attenuate activation of HTFs induced by TGF-β1 without obvious toxicity. The possible mechanism might be that rosiglitazone interferes with TGF-β/Smad signaling pathway.

Effect of peroxisome proliferator activated receptor γ2 on the proliferation and differentiation of rat osteoblasts

Objective To study the effect of peroxisome proliferator activated receptor2 (PPARγ2) on the proliferation and differentiation of osteoblasts. MethodsAfter cell culturing, identify the cells by ALP staining and mineralized nodules. Methyl thiazol tetrazolium (MTT) assay and PNPP assay were used to observe the effects of PPARγ2 on proliferation and differentiation of the cell. Results Rosiglitazone doesn't effect osteoblasts proliferation (F =1. 335 ,P ＞0. 05) but it could inhibit osteoblasts differentiation. ALP activity in osteoblasts were inhibited differently at the different concentrations of Rosiglitazone ( F =82. 304, P ＜ 0. 01 ). Conclusion Rosiglitazone may inhibit bone formation in a direct fashion by induction of differentiation of osteoblasts. Key words: Peroxisome proliferator activated receptorγ2 ; Rosiglitazone; Osteoblasts; Proliferation; Differentiation

All‐trans retinoic acid can intensify the growth inhibition and differentiation induction effect of rosiglitazone on multiple myeloma cells

Activation of PPARgamma by its ligands has shown potential anti-neoplastic effects in solid tumors. In this study, we investigate the effects of rosiglitazone (RGZ) alone as well as in combination with all trans-retinoic acid (ATRA) on human myeloma cell lines and try to address its potential mechanism. U266, RPMI-8226 and primary myeloma cells from patients were treated with different concentrations of RGZ in the presence or absence of ATRA and various biological responses were studied by the methods of [3H] thymidine incorporation, MTT, cell cycle analysis, Annexin V-PI staining, Wright-Giemsa staining, CD49e expression assay, light chain protein detection, RT-PCR and caspase-3 activity assay. We report that exposure to RGZ induced proliferation inhibition and viability reduction in a dose-dependent manner in both U266 and RPMI-8226 cells. A similar exposure to RGZ also induced cell cycle arrest and cell apoptosis of myeloma cells. A combination of RGZ with ATRA enhanced the effects of RGZ and induced cell cycle arrest and apoptosis more profoundly in both cell lines. RGZ treated cells displayed morphological characteristics of cell differentiation, and more evident signs of differentiation were observed when combined with ATRA. These changes were confirmed by the detection of CD49e expression and light chain protein secretion. Similar cell apoptosis and differentiation were observed when primary CD138+ myeloma cells were treated with RGZ and ATRA. The mRNA expressions of FLIP, XIAP and survivin were detected in both cell lines and the levels decreased significantly after culture with RGZ. The addition of ATRA in culture medium made these changes more apparently. Caspase-3 activity was increased upon exposure to RGZ in both U266 and RPMI-8226 cells while combination of RGZ and ATRA brought out more effective activation of caspase-3. Similar apoptosis and cell differentiation induced by RGZ and ATRA can also be observed in primary CD138+ cells from myeloma patients. Concomitant RXRalpha activation by ATRA enhanced the inhibitory effects of RGZ on myeloma cell proliferation, cell cycle, apoptosis and differentiation. Combination of RGZ and ATRA may be a useful therapy for human multiple myeloma.

Effect of Rosiglitazone on the proliferation and the production of transforming growth factor-beta 1 in cultured human Tenon' s capsule fibroblasts

To investigate the effect of Rosiglitazone on the proliferation and the production of transforming growth factor-beta 1 (TGF-beta 1) in cultured humans Tenon's capsule fibroblasts (HTFs). It was a experimental study. HTFs were cultured and subcultured in vitro. After HTFs were treated with different concentrations of Rosiglitazone, the proliferation was detected by MTT assay. The migration ability was detected by a scratch method. The production of TGF-beta 1 was determined by ELISA. TGF-beta 1 mRNA expression was examined by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). Compared with control group, Rosiglitazone significantly (F = 178.293, P < 0.01) inhibited the proliferation (0.33 +/- 0.01 vs 0.29 +/- 0.02) and the migration of HTFs in a dose-dependent manner with the concentrations ranged from 20 to 500 mg/L. Rosiglitazone also significantly (F = 86.404, P < 0.01) reduced the production of TGF-beta 1 in HTFs (323.48 +/- 13.69 vs 267.48 +/- 20.31). TGF-beta 1 mRNA was significantly (F = 176.102, P < 0.01) down-regulated (0.69 +/- 0.02 vs 0.55 +/- 0.02). This study suggests that the inhibition of the proliferation of Tenon's capsule and the migration of HTFs by Rosiglitazone is due, at least in part, to decrease the production of TGF-beta 1.

Inhibition of proliferation and transforming growth factor β3 protein expression by peroxisome proliferators-activated receptor γ ligands in human uterine leiomyoma cells

Rosiglitazone is known as the most potent and specific peroxisome proliferators-activated receptor gamma (PPAR-gamma) ligand. It has potentially far-reaching effects on pathophysiological processes, from cancer to atherosclerosis and diabetes. However, it is not clear whether rosiglitazone affects the protein expression of transforming growth factor beta3 (TGF-beta3) and the cell proliferation in human uterine leiomyoma cells in vitro. Human uterine leiomyoma tissues were dissected and cultured. Cells were divided into 5 groups: one control group and other four groups with different concentrations of rosiglitazone (10(-7), 10(-8), 10(-9) and 10(-10) mol/L). Cells were cultured for 72 hours in serum-free Dulbecco's modified Eagle's medium. MTT reduction assay was used to detect the cell proliferation. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of PPAR-gamma and TGF-beta3. Immunofluorescence staining was used to detect the expressions of PPAR-gamma and TGF-beta3 proteins. MTT reduction assay indicated that the treatment with rosiglitazone (from 10(-7) to 10(-9) mol/L) resulted in an inhibition of the cell growths after 72 hours (P < 0.01). RT-PCR analysis revealed that 10(-7) mol/L rosiglitazone significantly affected the gene expression at 72-hour: PPAR-gamma mRNA expression was up-regulated and TGF-beta3 mRNA was down-regulated and rosiglitazone at the concentration of 10(-7) mol/L affected these most effectively (P < 0.01). Immunofluorescence staining demonstrated that treatment with 10(-7) mol/L rosiglitazone resulted in the significant changes of PPAR-gamma and TGF-beta3 protein expressions compared with the other treatment groups and the control group at 72-hour (P < 0.01). All the effects of rosiglitazone on uterine leiomyoma cells were dose- and time-dependent in vitro. The present study demonstrates that the PPAR-gamma activator, rosiglitazone, inhibits the cell proliferation partly through the regulations of PPAR-gamma and TGF-beta3 expressions. The cross-talk between the signal pathways of PPAR-gamma and TGF-beta3 may be involved in the process.