[Chiral separation of fluvastatin enantiomers with in vitro cellular method]

OBJECTIVE

To establish a chiral separation method for determination of fluvastatin enantiomer with in vitro cellular model.

METHODS

The determination was performed on Chiralpak AD column (4.6 mm × 250 mm); and the phase consisted of hexane-isopropanol-trifluoroacetic acid (90:10:0.1) at a flow rate of 0.5 ml/min with UV detection of 239 nm.

RESULT

The standard curve was linear over the concentration range of 20 μmol/L-300 μmol/L (r² = 0.9993, r² = 0.9997). The recovery for this assay was (99.4 ± 0.8)%, precision for inter-assay and intra-assay was <10 %.

CONCLUSION

The normal-phase HPLC chiral separation method was accurate and suitable for study on the stereoselectivity of fluvastatin with in vitro cellular model.

Fluvastatin attenuates myocardial interstitial fibrosis and cardiac dysfunction in diabetic rats by inhibiting over-expression of connective tissue growth factor

BACKGROUND

Diabetic myocardiopathy is characterized by myocardial interstitial fibrosis and cardiac dysfunction. Statins were found to exert protective effects on cardiovascular disease by suppressing activation of small G proteins, independently of their lipid-lowering effect. The study investigated the effect of fluvastatin on myocardial interstitial fibrosis, cardiac function and mechanism of its action in diabetic rats.

METHODS

Twenty-four male SD rats were randomly assigned to 3 groups: control rats (n = 8), streptozotocin (STZ)-induced diabetic rats (n = 8), and diabetic rats treated with fluvastatin (administered fluvastatin orally, 10 mg/kg body weight per day, n = 8). Twelve weeks later, miniature cardiac catheter was inserted into the left ventricle to conduct hemodynamic examination. Then myocardium tissues were collected, collagen content was detected by picro-sirius red staining, real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of connective tissue growth factor (CTGF), and Western blotting was used to detect the protein expression of CTGF. Rho activity was determined by pull-down assay.

RESULTS

After 12 weeks, the left ventricular systolic pressure (LVSP) and maximum rate of left ventricular (LV) pressure rise and fall (+dP/dt max and -dP/dt max) were significantly lower and left ventricular end diastolic pressure (LVEDP) was higher in the diabetic rats than those in the control rats (P < 0.01). Moreover, in LV myocardial tissue of diabetic rats the collagen content, fibronectin, mRNA and protein expression of CTGF and the activity of RhoA were all significantly increased compared with the control rats (P < 0.01). Administration of fluvastain obviously improved the cardiac function of diabetic rats, attenuated fibronectin expression, mRNA and protein expression of CTGF and the activity of RhoA in LV myocardium of diabetic rats.

CONCLUSIONS

Fluvastatin attenuates cardiac dysfunction and myocardial interstitial fibrosis of diabetic rat by inhibiting activity of RhoA to down-regulate the overexpression of CTGF, and Rho/Rho-kinase pathway may be an important target in the treatment of diabetic cardiomyopathy.

Comparative study between high-dose fluvastatin and low-dose fluvastatin and ezetimibe with regard to the effect on endothelial function in diabetic patients

It is well established that statins improve the prognosis of patients with coronary artery disease. However, it is still unclear whether the protective effects of statins relate to lipid lowering alone or whether other pleiotropic effects may contribute. Thus, we compared the endothelial function among two groups of diabetic patients treated with fluvastatin 60 mg (F60) or fluvastatin 20 mg combined with ezetimibe 10 mg (F20/E10). The endothelial function was evaluated by measuring flow-mediated vasodilatation (FMD) at baseline and follow-up at 10 weeks. Similar improvements in FMD were observed in the two groups. The reduction in low-density lipoprotein cholesterol (LDL-C) was less pronounced in the F60 group, compared with the F20/E10 group. A significant reduction in remnant-like lipoprotein particles cholesterol (RLP-C) was observed in the F20/E10 group, but not in the F60 group. A correlation between the observed reduction in LDL-C or RLP-C and the improvement in FMD was observed in F20/E10 group. These results suggest that high-dose fluvastatin might have pleiotropic effects of potential clinical benefit, and that the combination of ezetimibe with a reduced dose of fluvastatin may also significantly improve endothelial function with reduction of LDL-C and RLP-C.

Fluvastatin, a lipophilic statin, induces apoptosis in human hepatocellular carcinoma cells through mitochondria-operated pathway

Fluvastatin, a lipophilic statin, was known to inhibit proliferation and induce apoptosis in many cancer cells. Its potential anticancer was evaluated in three hepatocellular carcinoma (HCC) cell lines (HepG2, SMMC-7721 and MHCC-97H). Cells were treated with fluvastatin in vitro and its effect on cell proliferation, cell cycle, invasion and apoptosis was determined. Mechanism of apoptosis induced by fluvastatin on HCC cell lines was also investigated through western blotting and mitochondrial membrane potential (MMP) analysis. It was observed that fluvastatin inhibited proliferation of HCC cells by inducing apoptosis and G2/M phase arrest in a dose-dependent manner. The results of cell invasion assay revealed that fluvastatin significantly decreased the invasion potency of HCC cells. A mitochondria-operated mechanism for fluvastatin induced apoptosis might be involved and was supported by Western blotting and MMP analysis. After fluvastatin treatment, expression of Bcl-2 and procaspase-9 were downregulated, cytochrome c (cytosolic extract), Bax and cleaved-caspase-3 protein expression were increased. Furthermore, a breakdown of MMP in HCC cells was observed. To conclude, these results have provided a rationale for clinical investigations of fluvastatin in future as a potential anticancer reagent for growth control of HCC.

[Fluvastatin's effect on atherogenesis in apolipoprotein-E knockout mice infected by cytomegalovirus]

OBJECTIVE

The goal of this study was to investigate whether murine cytomegalovirus (MCMV) is able to exacerbate the atherosclerotic process in apolipoprotein E knockout (apoE -/-) mice, and the effect of fluvastatin on the atherogenesis.

METHODS

The apoE-/- mice kept on a west diet were given low dosage of MCMV. At 14,18 and 24 weeks post infection, AS lesion were measured on aorta. The fluvastatin was administered, and AS lesion were measured accordingly above.

RESULTS

We observed that in the chronic phase of the infection, AS lesion area was significantly increased. MCMV gB mRNA was not amplified by real-time PCR from the arterial wall. The IgG antibody level of MCMV in blood plasma and the content of virus DNA in salivary gland were not correlated with AS lesions. After the administration of fluvastatin, there was no significant difference of AS lesions between MCMV infected group and mock-infected group.

CONCLUSION

MCMV may aggravate the AS lesion in apoE -/- mice in the chronic phase of infection, and promote more severe type of AS lesions. But it might not be the direct effects of mechanism of MCMV on the local lesion of AS. Fluvastatin could meliorate the progression of AS after MCMV infection, but this was not accomplished by decreasing MCMV duplication.

Induced expression of lectin-like oxidized ldl receptor-1 in vascular smooth muscle cells following Chlamydia pneumoniae infection and its down-regulation by fluvastatin

Microorganisms such as Chlamydia pneumoniae have been shown to infect vascular cells and are believed to contribute to vascular inflammation and atherosclerotic plaque development. Plasma levels of oxidized low density lipoprotein (oxLDL) have received considerable attention as potential predictors of prognosis in atherosclerotic diseases. Lectin-like oxidized LDL receptor-1 (LOX-1) is one of the major receptors for oxidized LDL. It was investigated whether C. pneumoniae infection can stimulate expression of LOX-1 in vascular smooth muscle cells. Expression of LOX-1 in VSMC was measured by RT-PCR and immunoblotting following C. pneumoniae infection. To examine the pharmacological effect of a HMG-CoA reductase inhibitor on LOX-1 expression, cells were co-incubated with fluvastatin immediately after infection. A dose and time dependent expression of LOX-1mRNA and protein was found in C. pneumoniae infected SMC. After heat and UV light treatment of the chlamydial inoculum the level of LOX-1 was reduced to that of mock-infected cultures. Furthermore, treatment of infected cells with fluvastatin decreased LOX-1 expression to baseline levels. The up-regulation of LOX-1 induced by C. pneumoniae could lead to continued lipid accumulation in atherosclerotic lesions. Together with the widespread expression of LOX-1, this might contribute to the epidemiologic link between C. pneumoniae infection and atherosclerosis. The effect of lowering the LOX-1 expression by fluvastatin may provide a pharmacological option of limiting oxLDL uptake via its scavenger receptor.

The inhibitory effect of statins on urinary 11-dehydrothromboxane levels

AIM

Elevated urinary 11-dehydrothromboxane levels place patients at an increased risk for experiencing cardiovascular events. Statins exert an inhibitory effect on platelets. The aim of our study was to determine the effect of 3-month statin therapy on 11-dehydrothromboxane elimination in two groups of patients, one not receiving antiplatelet therapy with acetylsalicylic acid and the other receiving 100 mg acetylsalicylic acid per day.

METHODS

We examined the urinary levels of 11-dehydrothromboxane in a total of 58 patients before and after 3-month therapy with a statin at standard doses (simvastatin, fluvastatin, atorvastatin). We also examined the plasma levels of total cholesterol, triglycerides, LDL- and HDL-cholesterol, C-reactive protein, and blood glucose.

RESULTS

After 3-month statin therapy, both groups of patients (with and without antiplatelet therapy) showed a significant decrease in urinary 11-dehydrothromboxane levels. Significant decreases were also seen in LDL- and total cholesterol, and C-reactive protein. Changes in the other parameters were not significant.

CONCLUSION

Three-month statin therapy significant reduces the rate of 11-dehydrothromboxane elimination, even in patients on acetylsalicylic acid. In addition to its usual lipid-lowering effect, it significantly decreases the plasma levels of C-reactive protein. Combination therapy with a statin plus acetylsalicylic acid may be effective even in patients with incomplete thromboxane inhibition on antiplatelet therapy with acetylsalicylic acid.

Effects of fluvastatin therapy on serum interleukin-18 and interleukin-10 levels in patients with acute coronary syndrome

OBJECTIVE

Experimental data demonstrate that inflammation plays an important role in the initiation, progression, and complications of atherosclerosis. Statins were shown to downregulate inflammatory cytokines.We conducted this study to investigate the effects of fluvastatin therapy on plasma interleukin-18 (IL-18) and interleukin-10 (IL-10) concentration in patients with acute coronary syndrome.

METHODS AND RESULTS

Serum IL-18 and IL-10 levels were measured in 90 patients with acute coronary syndrome, 47 patients with stable angina pectoris, and 55 normal control subjects. Patients in the acute coronary syndrome group were randomly assigned to a fluvastatin group and a routine group.The fluvastatin group was given fluvastatin 40 mg/day and the routine group a placebo.After one month of follow-up, serum IL-18, IL-10 levels, and serum lipid concentration were measured again. Serum IL-18 levels were significantly higher in the acute coronary syndrome group than in the stable angina pectoris group and the control group. However, serum IL-10 levels were significantly lower than in the stable angina pectoris group and the control group.After one month of treatment, the serum IL-18 levels decreased significantly and the serum IL-10 levels increased significantly in all patients with acute coronary syndrome, but the changes of serum IL-18 and IL-10 levels were more pronounced in the fluvastatin group. No relationship was observed between the rate of decrease of serum IL-18 or the rate of increase of serum IL-10 and serum lipids levels.

CONCLUSION

Inflammation plays an important role in the initiation of acute coronary syndromes. Fluvastatin possesses an anti-inflammatory effect, independent of its lipid-lowering action.

Local application of fluvastatin improves peri-implant bone quantity and mechanical properties: a rodent study

Statins are known to stimulate osteoblast activity and bone formation. This study examines whether local application of fluvastatin enhances osteogenesis around titanium implants in vivo. Ten-week-old rats received a vehicle gel (propylene glycol alginate (PGA)) or PGA containing fluvastatin (3, 15, 75 or 300 microg) in their tibiae just before insertion of the implants. For both histological and histomorphometric evaluations undecalcified ground sections were obtained and the bone-implant contact (BIC), peri-implant osteoid volume and mineralized bone volume (MBV) were calculated after 1, 2 and 4 weeks. Using the same models mechanical push-in tests were also performed to evaluate the implant fixation strength. After 1 week the MBV and push-in strength were significantly lower in the 300 microg fluvastatin-treated group than in the other groups (P<0.01). At 2 weeks, however, the BIC and MBV were both significantly higher in the 75 microg fluvastatin-treated group than in the non-fluvastatin-treated groups (P<0.01). Similar tendencies were observed at week 4. Furthermore, the data showed a good correlation between the MBV and the push-in strength. These results demonstrate positive effects of locally applied fluvastatin on the bone around titanium implants and suggest that this improvement in osseointegration may be attributed to calcification of the peri-implant bone.

A gene score of nine LDL and HDL regulating genes is associated with fluvastatin-induced cholesterol changes in women

While conventional pharmacogenetic studies have considered single gene effects, we tested if a genetic score of nine LDL- and HDL-associated single nucleotide polymorphisms, previously shown to predict cardiovascular disease, is related to fluvastatin-induced lipid change. In patients with asymptomatic plaque in the right carotid artery, thus candidates for statin therapy, we related score LDL [APOB(rs693), APOE(rs4420638), HMGCR(rs12654264), LDLR(rs1529729), and PCSK9(rs11591147)] and score HDL [ABCA1(rs3890182), CETP(rs1800775), LIPC(rs1800588), and LPL(rs328)] as well as the combined score LDL+HDL to fluvastatin-induced LDL reduction (+/- metoprolol) (n = 395) and HDL increase (n = 187) following 1 year of fluvastatin treatment. In women, an increasing number of unfavorable alleles (i.e., alleles conferring higher LDL and lower HDL) of score LDL+HDL (P = 0.037) and of score LDL (P = 0.023) was associated with less pronounced fluvastatin-induced LDL reduction. Furthermore, in women, both score LDL+HDL (P = 0.001) and score HDL (P = 0.022) were directly correlated with more pronounced fluvastatin-induced HDL increase, explaining 5.9-11.6% of the variance in treatment response in women. There were no such associations in men. This suggests that a gene score based on variation in nine different LDL- and HDL-associated genes is of importance for the magnitude of fluvastatin HDL increase in women with asymptomatic plaque in the carotid artery.

Statin-induced apoptosis linked with membrane farnesylated Ras small G protein depletion, rather than geranylated Rho protein

Rhabdomyolysis is a severe adverse effect of 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins). This myopathy is strongly enhanced by the combination with statins and fibrates, another hypolipidaemic agent. We have evaluated the initial step of statin-induced apoptosis by the detection of membrane flip-flop using flow cytometric analysis. L6 rat myoblasts were treated with various statins (atorvastatin (3 μm), cerivastatin (3 μm), fluvastatin (3 μm), pravastatin (3 mm), or simvastatin (3 μm)) for 2, 4 or 6 h followed by reacting with FITC-conjugated annexin V for the detection of initial apoptosis signal (flip-flop). Various statin-treated myoblasts were significantly stained with FITC-annexin V at 6 h, whereas they were not detected at 2 h. Moreover, immunoblot analysis indicated that when the cells were treated with cerivastatin (3 μm), membrane-associated Ras protein was activated and detached until 6 h, resulting in cell death through the consequent activation of caspase-8. On the other hand, since cytosolic Ras activation did not activate, there is still an unknown mechanism in statin-related Ras depletion. In conclusion, statin-induced apoptosis in muscular tissue was directly initiated by the farnesyl-anchored Ras protein depletion from cell membrane with subsequent apoptosis.

Role of cellular cholesterol in pharmacologic preconditioning with cyclosporine in experimental kidney transplantation

BACKGROUND/AIMS

Ischemia reperfusion injury in the early posttransplant period affects immediate graft function and late allograft dysfunction. Recently, we showed that pharmacologic preconditioning with a calcineurin inhibitor improved transplant outcomes in rat syngeneic kidney transplantation. There is also evidence that cellular cholesterol content increases after many types of renal injury.

METHODS

In this study, we looked at the effect of cyclosporine (CsA) on the donor kidney free cholesterol (FC) content in this model. Donor rats were pretreated with one dose of CsA 10 mg/kg administered 24 h or 7 days before being subjected to 2 h cold ischemia and then transplanted.

RESULTS

Pharmacologic preconditioning with CsA significantly improved renal function and histology and increased donor kidney FC content. On the other hand, fluvastatin co-administration with CsA abrogated that beneficial effect in association with a decrease in donor kidney FC content.

CONCLUSION

CsA preconditioning leads to better outcomes in kidney transplantation and is associated with up-regulation of renal FC content. The latter may then contribute to acquired cytoresistance, possibly by stabilizing the plasma membrane. Thus, use of statins around the time of transplantation may need to be evaluated until further studies are conducted to determine the clinical relevance of this observation.

Lovastatin and fluvastatin reduce viremia and the pro-inflammatory cytokines in the patients with chronic hepatitis C

BACKGROUNDS/AIMS

Certain statins interfere with the mechanism of the hepatitis C virus replication. We aimed at studying the effect of statins on the level of viremia and of the pro-and anti-inflammatory cytokines in the patients with chronic hepatitis C.

METHODOLOGY

We took in our study all the patients with chronic hepatitis C placed in the evidence of the clinics of internal medicine of the Emergency County Clinical Hospitals of Braşov, Oradea and Sibiu, who had been identified with viremias. The patients were treated with fluvastatin 40 mg/day or lovastatin 20 mg/day for 28 days. The level of viremia, hemoleukogram, hepatic biochemical tests and the pro and anti-inflammatory hepatic cytokines were analysed before and after the treatment. The final results were compared with the initial ones, as well as between the 2 groups.

RESULTS

Regarding those 99 analysed patients, the initial average viremia was of 2376074 +/- 3427596 UI/ml, while the final one was of 1321136 +/- 1343570 UI/ml (p = 0.000987). Both, in the group treated with lovastatin, as well as in that treated with fluvastatin, the decrease of viremia was significant from the statistics point of view (p = 0.032, respectively p = 0.00092). Lovastatin administration resulted in the significant decrease of the pro-inflammatory cytokines IL-6 and TNF-alfa, while that of fluvastatin brought about the significant decrease of the serum levels of IL-6, IL-8 and TNF-alfa. There were no significant differences, statistically speaking, between the 2 determinations, regarding the levels of IL-10 (anti-inflammatory cytokine) and those of erythropoietin. Transaminases average level did not vary significantly after those 4 weeks of statins treatment.

CONCLUSIONS

Lovastatin and fluvastatin, significantly decrease the level of viremia, of IL-6 and TNF-alpha in the patients with chronic hepatitis C.

Fluvastatin and perioperative events in patients undergoing vascular surgery

BACKGROUND

Adverse cardiac events are common after vascular surgery. We hypothesized that perioperative statin therapy would improve postoperative outcomes.

METHODS

In this double-blind, placebo-controlled trial, we randomly assigned patients who had not previously been treated with a statin to receive, in addition to a beta-blocker, either 80 mg of extended-release fluvastatin or placebo once daily before undergoing vascular surgery. Lipid, interleukin-6, and C-reactive protein levels were measured at the time of randomization and before surgery. The primary end point was the occurrence of myocardial ischemia, defined as transient electrocardiographic abnormalities, release of troponin T, or both, within 30 days after surgery. The secondary end point was the composite of death from cardiovascular causes and myocardial infarction.

RESULTS

A total of 250 patients were assigned to fluvastatin, and 247 to placebo, a median of 37 days before vascular surgery. Levels of total cholesterol, low-density lipoprotein cholesterol, interleukin-6, and C-reactive protein were significantly decreased in the fluvastatin group but were unchanged in the placebo group. Postoperative myocardial ischemia occurred in 27 patients (10.8%) in the fluvastatin group and in 47 (19.0%) in the placebo group (hazard ratio, 0.55; 95% confidence interval [CI], 0.34 to 0.88; P=0.01). Death from cardiovascular causes or myocardial infarction occurred in 12 patients (4.8%) in the fluvastatin group and 25 patients (10.1%) in the placebo group (hazard ratio, 0.47; 95% CI, 0.24 to 0.94; P=0.03). Fluvastatin therapy was not associated with a significant increase in the rate of adverse events.

CONCLUSIONS

In patients undergoing vascular surgery, perioperative fluvastatin therapy was associated with an improvement in postoperative cardiac outcome. (Current Controlled Trials number, ISRCTN83738615.)

[The effect of valsartan and fluvastatin on the connective tissue growth factor expression in experimental diabetic cardiomyopathy]

OBJECTIVE

To investigate the effect of valsartan and fluvastatin on the expression of connective tissue growth factor in early diabetic cardiomyopathy.

METHODS

Forty male SD rats were randomly divided into five groups: normal control group, diabetic model (DM) group, DM + valsartan group (30 mg x kg(-1) x d(-1)), DM + fluvastatin group (4 mg x kg(-1) x d(-1) ) and DM + valsartan + fluvastatin group (valsartan 30 mg x kg(-1) x d(-1) + fluvastatin 4 mg x kg(-1) x d(-1)). After 12 weeks, miniature cardiac catheter was inserted into the left ventricle to conduct hemodynamic examination. Then myocardial tissue was collected and collagen content was detected with Van-Gieson staining. The levels of connective tissue growth factor (CTGF) mRNA expression in myocardium were determined using RT-PCR and Western blot was used to detect the protein expression of transforming growth factor (TGF) beta, CTGF, collagen I and III.

RESULTS

By the end of the experiment, left ventricular diastolic function was significantly decreased in the DM group in comparison with the control group (P < 0.05). As compared with the normal control group, myocardial collagen content was significantly increased 1.1 fold (P < 0.05), and the heart weight/body weight ratio was increased 37% in the DM group, but it was significantly reduced in the valsartan group and the fluvastatin group in comparison with the DM group (both P < 0.05). The mRNA expression of CTGF was significantly higher in the DM group than in the control group, but it was significantly lower in the valsartan group and fluvastatin group than that in the DM group (both P < 0.05). The values of protein expression of CTGF, TGFbeta, collagen I and III were all significantly higher in the DM group than those in the control group (all P < 0.05). The protein expression of CTGF, TGFbeta, collagen I and III in the valsartan group and fluvastatin group was all significantly lower than that in the DM group (P < 0.05). It was shown that treatment with valsartan or fluvastatin was effective for myocardial fibrosis in diabetic SD rats and valsartan combined with fluvastatin would be still better.

CONCLUSION

Valsartan and fluvastatin can reduce myocardial fibrosis, resulting in prevention of left ventricular remodeling and improvement of cardiac function in an experimental model of diabetic cardiomyopathy. The process was related to the inhibition of the overexpression of CTGF and TGFbeta and reduction in cardiac extracellular matrix collagen content. It is also shown that a better result may be obtained with the coadministration of the two drugs than using one alone.

Inhibitors of Differentiation/DNA Binding Proteins Id1 and Id3 Are Regulated by Statins in Endothelial Cells

Id proteins (inhibitors of differentiation), which are involved in the control of cell cycle progression, can delay cellular differentiation and senescence and have been implicated in angiogenesis. The regulation of Id proteins in endothelial cells (ECs) by proangiogenic statins has not been investigated yet and remains unresolved. In this study, human dermal microvascular ECs (HDMECs) were stimulated with fluvastatin, vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and serum in vitro. The regulation of Id1, Id3, p21, p27, and p53 and the phosphorylation of AKT was investigated by Western blotting. Id1 was up-regulated by fluvastatin and serum, but not by VEGF and HGF. Fluvastatin did not regulate p21 and p27, but down-regulated Id3 and p53 slightly. In contrast to VEGF and HGF, fluvastatin did not result in AKT phosphorylation, indicating that this pathway is not involved in the control of endothelial Id1 expression. These experiments demonstrate for the first time that Id1 can be up-regulated and p53 down-regulated by a statin in HDMECs. Regulation of these proteins in ECs may account for the proangiogenic effect of statins.