Nrf2-inducing and HMG-CoA reductase inhibitory activities of a polyphenol-rich fraction of Guazuma ulmifolia leaves

To fractionate and identify polyphenols from Guazuma ulmifolia Lam. leaves, and to explore their antioxidant, 5-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitory, and Nrf2 modulatory activities. Methods: The 1,1-diphenyl-2-picrylhydrazyl assay was used to evaluate the antioxidant activity of a polyphenolic fraction of the extract of Guazuma ulmifolia Lam. leaves. THP-1 gene reporter cell lines constructed with a transcriptional response element specific for Nrf2 and a minimal promoter for the firefly luciferase–green fluorescent protein transgene were used to determine the effect of the polyphenolic fraction on the Nrf2 signaling pathway. Furthermore, an assay of HMG-CoA reductase inhibitory activity was performed by using a commercial enzyme kit. Polyphenolic compounds were identified by liquid chromatography-tandem mass spectrometry. Results: The polyphenolic fraction showed fairly strong antioxidant activity [IC50 = (14.90 ± 4.70) μg/mL] and inhibited HMG-CoA reductase activity by 69.10％, which was slightly lower than that by pravastatin (84.37％) and quercetin (84.25％). Additionally, the polyphenolic fraction activated the Nrf2 antioxidant signaling pathway at 500 μg/mL. Eleven subfractions resulting from the column chromatography separation of the polyphenolic fraction also showed relatively strong antioxidant activities (IC50: 17.46–217.14 μg/mL). The subfraction (F6) stimulated the Nrf2 signaling pathway and had HMG-CoA reductase inhibitory activity (65.43％). Moreover, the subfraction contained two main flavonoids: quercetin and quercimeritrin. Conclusions: The polyphenolic fraction of Guazuma ulmifolia could induce antioxidant genes via the Nrf2/antioxidant regulatory elements pathway, and is a promising candidate for an inhibitor of HMG-CoA reductase.

Effect of Rosuvastatin on Bovine Pericardial Aortic Tissue Valve Calcification in a Rat Subdermal Implantation Model

BACKGROUND AND OBJECTIVES: There are pathophysiologic similarities between calcification and atherosclerosis because both are the product of an active inflammatory process. The aim of this study was to examine the effects of statin treatment on calcification in bovine pericardial tissue valves. MATERIALS AND METHODS: Forty Sprague-Dawley rats were randomly divided into 4 groups according to hypercholesterolemia induction and statin intake (Group 1, n=10: normal diet without statin treatment, Group 2, n=10: normal diet with statin treatment, Group 3, n=10: high fat diet without statin treatment, Group 4, n=10: high fat diet with statin treatment). Serum lipid levels were measured just before the experiment and after 4 and 12 weeks. Bovine pericardial tissue valve cusps were surgically implanted in rat dorsal subcutis at 4 weeks. After the surgery, statin was administered daily to Groups 2 and 4. Serum interleukin-6 (IL-6) level was measured at 5 weeks. Cusps were explanted at 12 weeks and calcium levels were determined by atomic absorption spectroscopy. RESULTS: Mean IL-6 was significantly higher in Group 3 at 5 weeks (7.14, 2.03, 31.70, and 6.90 pg/dL for each group, respectively). Mean calcium level in Group 3 was significantly higher among groups but Group 4 was significantly lower compared to Group 3 and was similar to Group 1, 2 (1.86, 1.92, 2.55, and 1.80 mg/g for each group, respectively, p<0.01). CONCLUSION: Hypercholesterolemia may be a significant risk factor for bovine pericardial valve calcification. Statin treatment significantly attenuated calcification of bovine pericardial valve tissue in a rat subdermal implantation model and might prolong the durability of bioprostheses.

Myotonic Potentials in the Myopathy Induced by HMG-CoA Reductase Inhibitor

HMG-CoA reductase inhibitor is widely used for the treatment of dyslipidemia, and for the prevention of stroke and cardiovascular disease. However, it is necessary to consider the adverse effects associated with this drug. Myopathy is a well-known side effect of statin therapy, but myotonic potentials in cases with statin myopathy have thus far been reported only rarely. We report four cases of myopathy with myotonic potentials on electromyography after multidrug administration. All of the patients recovered shortly after statin withdrawal.

The Effects of Combined Treatment with an HMG-CoA Reductase Inhibitor and PPARgamma Agonist on the Activation of Rat Pancreatic Stellate Cells

BACKGROUND/AIMS: Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) and peroxisome proliferator-activated receptor gamma (PPARgamma) ligands can modulate cellular differentiation, proliferation, and apoptosis through various pathways. It has been shown that HMG-CoA reductase inhibitors and PPARgamma agonists separately inhibit pancreatic stellate cell (PaSC) activation. We studied the effects of a combination of both types of drugs on activated PaSCs via platelet-derived growth factor (PDGF), which has not previously been reported. The present study was performed to elucidate the underlying mechanisms of these effects by focusing on the impact of the signaling associated with cell-cycle progression. METHODS: Primary cultures of rat PaSCs were exposed to simvastatin and troglitazone. Proliferation was quantified using the BrdU method, and cell-cycle analysis was performed using a fluorescent activated cell sorter. The protein expression levels of smooth muscle actin (SMA), extracellular signal-regulated kinase (ERK), and a cell cycle machinery protein (p27Kip1) were investigated using Western blot analysis. RESULTS: Simvastatin reversed the effects of PDGF on cell proliferation in a dose-dependent manner. The combination of a low concentration of simvastatin (1 mM) and troglitazone (10 mM) synergistically reversed the effects of PDGF on cell proliferation but had no effect on cell viability. The expression of a-SMA was markedly attenuated by combining the two drugs, which blocked the cell cycle beyond the G0/G1 phase by reducing the levels of phosphorylated ERK and reversed the expression of p27Kip1 interrupted by PDGF. CONCLUSIONS: Simvastatin and troglitazone synergistically inhibited cell proliferation in activated PaSCs by blocking the cell cycle beyond the G0/G1 phase. This inhibition was due to the synergistic modulation of the ERK pathway and the cell cycle machinery protein p27Kip1.

Comparative Clinical Evaluation of the Efficacy and Safety between the Original Drug and Generic Products (II) / 医薬品情報学

<b>Objective: </b>The purpose of this study is to compare the clinical efficacy between original drugs and generic products.  Candidate drugs included two types of hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitors, simvastatin and pravastatin, because of their importance at reducing the health expenditure for hyperlipidemia.<br><b>Design: </b>We retrospectively evaluated the efficacy (total cholesterol, triglyceride, low-density lipoprotein and high-density lipoprotein levels), safety (biochemical parameters), and medication adherence based on patient data.  We set the follow-up period at 6 months before and after substitution.  Data were analyzed by paired-sample <i>t</i>-tests (statistical significance level of 0.05).<br><b>Methods: </b>The subjects included in this study were ambulatory patients visiting Nakajima Hospital for dyslipidemia treatment.  Selected patients included those taking both the original drug and the generic product; i.e., patients who had substituted the original drug Lipovas® for the generic product Simvastatin OHARA, or those who had substituted the original drug Mevalotin® for the generic drug Pravatin®.<br><b>Results: </b>A total of 118 patients in the simvastatin study and 43 patients in the pravastatin study were candidates for the present study.  We found that there were no significant differences before and after substitution.  Even though there were differences in some of the biochemical parameters, the range remained within normal levels.  With regard to medication adherence, we found no significant differences.<br><b>Conclusion: </b>In this study, we found no significant differences before and after substituting medications with generic drugs.  Additionally, we found no subjective symptom changes after substitution.  To develop clinical information on generic products and to store such information, it is important that pharmaceutical products be used appropriately.

HMG CoA Reductase Inhibitors Inhibit HCV RNA Replication of HCV Genotype 1b but Not 2a

Replication of hepatitis C virus (HCV) is regulated by statin, one of 3-hydroxy-3-methylglutaryl CoA reducatase (HMG CoA reductase) inhibitors that block mevalonate pathway and cholesterol biosyntheis, which has been used usefully for health improvement and disease control in clinic. In order to know which statin can be used to inhibit HCV replication, we examined the effects of HCV genotype 1b replication by 6 kinds of statins with different structure. We treated six statins to HCV genotype 1b replicon cell. Atorvastatin, simvastatin, fluvastatin, mevastatin, and lovastatin inhibited HCV RNA replication and HCV protein expression in HCV genotype 1b replicon cells, though pravastatin did not affect HCV replication. In order to know whether inhibition of HCV replication by statin is depended on HCV genotype, we treated the statins to HCV genotype 2a producing cells, and investigated HCV RNA replication and HCV protein expression. HCV RNA replication and protein expression was not affected in HCV genotype 2a producing cells by treatment of statins and cholesterol inhibitor. These results suggest that HMG-CoA reductase and cholesterol inhibitors might be used depending on HCV genotype. In addition, inhibition of HCV genotype 1b replication by statins has been depended on structure of various statins which should be seriously selected for HCV clinic. In future, we will study on inhibition of another HCV genotype replication by HMG-CoA reductase and cholesterol inhibitors.

The Anti-Inflammatory Effects of Statin in 5/6 Nephrectomized Rats / 대한내과학회지

BACKGROUND/AIMS: In a previous study, statin therapy reduced proteinuria and ameliorated the progression of chronic kidney disease. However, in patients with chronic renal failure (CRF), the beneficial effect of statin therapy on the preservation of renal function has not been determined. Thus, we determined the effect of rosuvastatin on CRF. METHODS: Male Sprague-Dawley rats (6 weeks old) were subjected to 5/6 nephrectomy. Six weeks after the procedure, the rats were divided into control and rosuvastatin-treated groups. Body weight and blood/urine biochemical parameters were measured 6 weeks after 5/6 nephrectomy and 8 weeks after the start of rosuvastatin treatment. Remnant kidneys were harvested at 6 (n = 4) and 14 (n = 8) weeks after 5/6 nephrectomy. RESULTS: During rosuvastatin treatment, changes in body weight and serum total and low-density lipoprotein cholesterol did not differ significantly between the control and rosuvastatin-treated groups. Although serum creatinine and proteinuria increased in both groups, the differences were not significant (p = 0.24 and 0.77, respectively). Immunohistochemical staining, enzyme-linked immunosorbent assays, and western blotting showed that the expression of transforming growth factor-beta1 and intracellular adhesion molecule-1 were reduced in the rosuvastatin-treated group. CONCLUSIONS: Long-term statin treatment may attenuate the inflammatory process in the progression of renal failure.

The Anti-Inflammatory Effects of Statin in 5/6 Nephrectomized Rats / 대한내과학회지

BACKGROUND/AIMS: In a previous study, statin therapy reduced proteinuria and ameliorated the progression of chronic kidney disease. However, in patients with chronic renal failure (CRF), the beneficial effect of statin therapy on the preservation of renal function has not been determined. Thus, we determined the effect of rosuvastatin on CRF. METHODS: Male Sprague-Dawley rats (6 weeks old) were subjected to 5/6 nephrectomy. Six weeks after the procedure, the rats were divided into control and rosuvastatin-treated groups. Body weight and blood/urine biochemical parameters were measured 6 weeks after 5/6 nephrectomy and 8 weeks after the start of rosuvastatin treatment. Remnant kidneys were harvested at 6 (n = 4) and 14 (n = 8) weeks after 5/6 nephrectomy. RESULTS: During rosuvastatin treatment, changes in body weight and serum total and low-density lipoprotein cholesterol did not differ significantly between the control and rosuvastatin-treated groups. Although serum creatinine and proteinuria increased in both groups, the differences were not significant (p = 0.24 and 0.77, respectively). Immunohistochemical staining, enzyme-linked immunosorbent assays, and western blotting showed that the expression of transforming growth factor-beta1 and intracellular adhesion molecule-1 were reduced in the rosuvastatin-treated group. CONCLUSIONS: Long-term statin treatment may attenuate the inflammatory process in the progression of renal failure.

Effects of Ezetimibe Added to Ongoing Statin Therapy on C-Reactive Protein Levels in Hypercholesterolemic Patients

BACKGROUND AND OBJECTIVES: Ezetimibe alone does not decrease C-reactive protein (CRP) levels in hypercholesterolemic patients. However, several reports have suggested that ezetimibe might potentiate the effect of statin not only on cholesterol but also on CRP when administered together. We investigated the effect of ezetimibe on CRP levels in patients taking statins. SUBJECTS AND METHODS: Patients who had not achieved recommended low density lipoprotein-cholesterol (LDL-C) goals with statin therapy were divided into two groups, the ezetimibe group (n=60) and the control group (n=60). A third group of hypercholesterolemic patients without statin therapy was treated with statin (n=59). Patients with CRP level 10 mg/L were excluded. Lipid and CRP levels were measured before therapy commenced, and after 2 months of therapy. RESULTS: Ezetimibe decreased cholesterol and LDL-C levels by 20.2% (p=0.000) and 28.1% (p=0.000) respectively. However, ezetimibe did not reduce CRP levels (from 0.83+/-0.68 to 1.14+/-1.21 mg/dL, p=0.11). CRP levels remained unchanged in the control group (p=0.42). In contrast, statin lowered CRP levels (from 0.82+/-0.73 to 0.65+/-0.57 mg/dL, p=0.008). In patients taking statins, changes in CRP levels were not associated with changes in LDL-C (r=-0.02, p=0.87), but with baseline CRP levels (r=-0.38, p=0.000). CONCLUSION: Ezetimibe failed to reduce CRP levels in hypercholesterolemic patients taking statins despite significant reduction of LDL-C. This finding suggests that the anti-inflammatory effect of statin may not be secondary to cholesterol reduction, but via other mechanisms.

Effect of Additional Statin Therapy on Endothelial Function and Prognosis in Patients With Vasospastic Angina

BACKGROUND AND OBJECTIVES: Vasospastic angina is correlated with endothelial dysfunction. We compared endothelial function using flow-mediated vasodilatation (FMD) and circulating endothelial progenitor cells (EPCs) between patients with vasospasm and those without vasospasm and studied the effect of statin therapy on the changes of FMD and EPCs in vasospastic angina patients. SUBJECTS AND METHODS: In 133 patients who underwent an ergonovine provocation test, endothelial function was compared based on the presence or absence of spasm. The patients with coronary artery spasm (74 patients) were randomly assigned to either the 10 mg rosuvastatin group or the placebo group. We compared changes in the FMD and EPCs level for 6 months from the time of enrollment between the two groups. RESULTS: The incidence of cigarette smokers was higher in vasospastic angina patients than in those without spasm (p<0.001). The number of EPCs (68.6+/-36.1 vs. 103.7+/-39.3/200 microliter, p<0.001) and the FMD (7.1+/-4.5 vs. 8.6+/-3.6%, p=0.044) were significantly lower in patients with coronary artery spasm than in those without spasm. After 6 months of rosuvastatin treatment, the number of CD45(low)CD34(+) vascular endothelial growth factor receptor 2 (VEGFR2)(+) cells, which was defined as EPCs, increased significantly from 73.1+/-37.8/200 microliter to 99.1+/-37.8/200 microliter (p=0.002). The FMD was significantly ameliorated from 7.3+/-4.1 to 9.3+/-3.4% after 6 months of treatment (p<0.001). The FMD was correlated with the EPCs count before treatment (r=0.229, p=0.049) and after 6 months of treatment (r=0.268, p=0.020). CONCLUSION: The number of circulating EPCs and the FMD were reduced in vasospastic angina, and statin treatment increased the number of EPCs and the FMD. The EPCs level was correlated with the FMD.

Renoprotective effect of simvastatin on adriamycin-induced nephropathy in rats / 第三军医大学学报

Objective To investigate the role of interleukin-1 beta (IL-1?) in glomerulosclerosis secondary to adriamycin (ADR)-induced nephropathy in rats, and the effect of simvastatin on the expression of IL-1?. Methods Male Sprague-Dawley rats were randomly divided into normal control, ADR-induced nephropathy (model), and simvastatin-treated ADR nephropathy (treatment) groups. After ADR-induced nephropathy establishment in model and treatment groups, and eleven weeks of intragastrical administer of normal saline in normal control and model groups and of simvastatin in treatment group, the expression of IL-1? was detected by immunohistochemistry, RT-PCR and ELISA. Histopathological change of renal tissues was observed under light microscope, and glomerulosclerosis index (GSI) was also evaluated. Results Higher expression of IL-1? in kidney and GSI, as well as more severe loss of renal function were observed in model group than those in control group (all P

Effects of Simvastatin Alone or Combined With Ramipril on Nitric Oxide Bioactivity and Inflammation Markers in Hypercholesterolemic Patients

BACKGROUND AND OBJECTIVES: Because the mechanisms of the biological effects of statin and antiotensin converting enzyme inhibitor therapies differ, the vascular responses to these therapies were studied in hypercholesterolemic patients. MATERIALS AND METHODS: Simvastatin, 20 mg, placebo or ramipril, 10 mg, were administered daily for 2 months, with a 2 month washout, to 32 hypercholesterolemic patients. This was a randomized, double-blind, placebo-controlled, crossover in design study. RESULTS: Simvastatin alone, or in combination with ramipril, significantly changed the lipoproteins, and improved the percentage of the flow-mediated dilator response to hyperemia by 46+/-48% and by 59+/-66%, respectively, relative to the baseline measurements (both p<0.001). The plasma malondialdehyde levels were reduced, relative to baseline measurements, by 6+/-57% (p=0.045) and 13+/-47% (p=0.045 and p<0.001, respectively) and plasma levels of monocyte chemoattractant protein-1 by 3+/-27% and by 9+/-16%, respectively (p=0.113 and p=0.001, respectively). The C-reactive protein were also reduced, relative to baseline measurements, by 17+/-75% and by 17+/-37%, respectively (p=0.003 and p=0.001, respectively). However, simvastatin combined with ramipril changed, to a greater extent, but was statistically insignificant, the percentage of the flow-mediated dilator response to hyperemia, and the plasma monocyte chemoattractant protein-1 levels, than simvastatin alone. CONCLUSION: Compared with simvastatin alone, the addition of ramipril improved the endothelial function to greater extent, but was statistically insignificant, in hypercholes-terolemic patients.

The Effects of Long Term Use of HMG-CoA Reductase Inhibitor on the Level of Lp (a)

BACKGROUND: Lipoprotein (a) concentration is mainly determined by apo (a) genotype, but elevated in the atherosclerotic vascular disease more than in normal group with the same apo (a) phenotype. It has been known that Lp (a) has independent metabolism in contrast with other lipoproteins and that the use of cholesterol lowering agent such as HMG-CoA reductase inhibitor for 6 months does not change the level of Lp (a). The results of several studies suggests that Lp (a) may be related to inflammation of atherosclerotic plaque and therefore, long term use of cholesterol lowering agents make plaque stable by reduction of inflammation at plaque. We hypothesized that there is a relationship between long term use of HMG-CoA reductase inhibitor and change of Lp (a) level. We prospectively measured Lp (a), lipids and inflammatory markers before and after long term use of HMG-CoA reductase inhibitor to examine our hypothesis. METHODS: Forty-nine subjects (M:F=28:21, age=59.1+/-12.0) with hyperlipidemia were administered HMG-CoA reductase inhibitor for 15 months (minimum 6 months, maximun 44 months), and Lp (a), lipids and inflammatory markers were measured before and after use of the HMG-CoA reductase inhibitor. In control group (ninty-nine subjects, M:F=60:39, age=61.2+/-9.2), these parameters were measured more than 6 months. RESULTS: In the hyperlipidemia group who were given HMG-CoA reductase inhibitor, baseline levels of total cholesterol, TG, LDL were significantly elevated more than those of the control group, but Lp (a) and inflammatory markers were not significantly different. After use of HMG-CoA reductase inhibitor, the level of Lp (a) was reduced significantly (before 28.9+/-29.3 mg/dl, after 20.0+/-19.0 mg/dl, p=0.009), but not significantly in the control group. There was a minimal relation between baseline Lp (a) levels and percent changes of Lp (a) levels. Total cholesterol and LDL levels reduced significantly after use of the drug, but inflammatory markers did not. CONCLUSION: These data showed that Lp (a) level in the hyperlipidemia group after the long term use of HMG-CoA reductase inhibitor decreased significantly. We suggest that these changes of Lp (a) level may be one of reliable markers for plaque stability in atherosclerotic vascular disease.

Antiproliferative effect of HMG CoA reductase inhibitor on ADPKD cyst-lining epithelial cell and its mechanism / 中华肾脏病杂志

Objective To investigate the antiproliferative effect of HMG CoA reductase inhibitor on ADPKD cyst-lining epithelial cells and its possible mechanism. Methods Cell viability was assayed by MTT. Membrane-bounded p2lras was detected by immunoblotting. The expression of c-jun and c-fos was examined by immunocytochemistry. Results After ADPKD cyst-lining epithelial cells were exposed to HMG CoA reductase inhibitor, proliferation was markedly inhibited( P

Effect of Pravastatin on Serum Lipids of Patient with Primary Hyperlipidemia

A new hypolipidemic drug, pravastatin, hydroxymethylglutaryl coenzyme A reductase inhibitor was administered to 33 patients with primary hyperlipidemia, 10mg daily for 8 weeks and sequential changes of lipid profile were analysed as follows. 1) Mean value at baseline period of total cholesterol, triglyceride, high and low density lipoprotein cholesterol were 260, 220, 51 and 163mg/dl respectively. 2) Total cholesterol showed 21% decrease at the end of 8 weeks and that of LDL-cholesterol were 30%. 3) Triglyceride decreased 16% at the end of 8 weeks and increment of HDL-cholesterol was 8% at the end of 8 weeks. 4) No serious side reactions were observed except one patient, who showed generalized skin rash which last 3 days and did not prevent further medication. In conclusion, pravastatin is a safe and useful hypolipidemic agent for the patient with primary hyperlipidemia.

Effect of fluvastatin on the expression of myocardial IL-1? in rats with heart failure after acute myocardial infarction / 中国药理学通报

Aim To investigate the effect of fluvastatin(FV)on the expression of IL-1? mRNA of left ventricular(LV) myocardium in rats with heart failure after acute myocardial infarction(AMI).Methods 6 h after ligating left coronary artery,surviving AMI female SD rats were randomly assigned to: ①AMI control;②AMI+FV;③sham-operated group,which was randomly selected as non-infarction control.After 8 weeks of therapy,we assessed cardiac function,hemodynamics,ventricular remodeling parameters and IL-1? mRNA expression in the infarcted and non-infarcted area(IA,NIA).Results Compared with the sham-operated group,LV end-diastolic dimension(LVEDD),LV end-diastolic volume(LVEDV),E-wave,E-wave deceleration,E/A ratio,LV end diastolic pressure(LVEDP),relative weight(LVRW),right ventricular relative weight(RVRW),collagen volume fraction(CVF) and IL-1? mRNA in NIA were all significantly increased in the AMI group(all P

Role of intracellular calcium in proliferation inhibition of MCF-7 cells induced by HMG-CoA reductase inhibitor / 第三军医大学学报

Objective To study the effects of HMG CoA reductase inhibitor, lovastatin (LOV), on the proliferation of human breast cancer cell MCF 7 and the role of intracellular calcium concentration ([Ca 2+ ]i) in this event. Methods After treated with LOV at the dosages of 4, 8 and 16 ?mol/L for 1-3 d respectively, the proliferation of MCF 7 cells was examined with MTT, and the distributions of cell cycles with FCM assay. Meanwhile, the change of [Ca 2+ ]i of MCF 7 cells was observed with laser scanning confocal microscopy, and the expression of plasma membrane calcium ATPase isoform 1 (PMCA1) mRNA with RT PCR. Results Lovastatin, inhibited the proliferation of MCF 7 cells and arrested MCF 7 cells in the G 0/G 1 phase of cell cycle, in a dose and time dependent manner. However, apoptosis of LOV treated MCF 7 cells was not obvious. Simultaneously, LOV increased [Ca 2+ ]i of MCF 7 cells, but didn't change the expression of PMCA1 mRNA. Conclusion The results suggest that LOV has the capabilities of inhibiting the proliferation of MCF 7 cells and arresting them in G 0/G 1 phase. These effects of LOV maybe correlate with LOV changing the function of PMCA1and increasing [Ca 2+ ]i of MCF 7 cells.