Fluvastatin, a new inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, suppresses very low-density lipoprotein secretion in puromycin aminonucleoside-nephrotic rats

Effects of rosuvastatin on glomerular capillary size-selectivity function in rats with renal mass ablation

BACKGROUND

Evidence is accumulating that statins can reduce proteinuria and disease progression in chronic kidney disease. However, some safety concerns have been recently raised on the use of these agents, mainly due to transient episodes of proteinuria observed in patients receiving high doses of rosuvastatin.

METHODS

We investigated in rats with renal mass ablation (RMR) whether rosuvastatin (5 or 20 mg/day) worsens proteinuria as compared to untreated RMR animals. Moreover, we also examined whether rosuvastatin-induced changes in proteinuria would be due to the effect of the drug on permselective properties of glomerular capillary barrier, measured by the fractional clearance of graded-size Ficoll molecules and/or by proximal tubular mechanisms, by assessing urinary excretion of beta(2)-microglobulin.

RESULTS

RMR rats given rosuvastatin for 28 days showed a progressive increase in proteinuria, with values numerically but not significantly higher than those in RMR animals given the vehicle. In RMR rats, rosuvastatin did not significantly affect the fractional clearance of Ficoll as compared to vehicle-treated RMR animals. A significant correlation was found between urinary protein and beta(2)-microglobulin excretion in rats treated with rosuvastatin (r = 0.936, p < 0.001), but not in those given vehicle. Renal function, glomerular and tubulointerstitial injury were comparable in rosuvastatin-treated and untreated RMR rats at the end of the 28-day follow-up.

CONCLUSION

In rats with RMR, rosuvastatin mildly enhances urinary protein excretion rate. This, however, was not the result of further changes in the size-permselective function of glomerular capillary barrier.

Effect of the lipoprotein lipase activator NO-1886 on adriamycin-induced nephrotic syndrome in rats

Hyperlipidemia associated with nephrotic syndrome may play a role in the deterioration of renal function. Tsutsumi et al have previously reported that the novel compound NO-1886 increases lipoprotein lipase (LPL) activity, resulting in a reduction of plasma triglycerides and an elevation of high-density lipoprotein (HDL) cholesterol in normal rats. The aim of this study was to ascertain whether NO-1886 suppresses the renal injury by treatment of the hyperlipidemia in an Adriamycin (Kyowa Hakko Kogyo, Tokyo, Japan) induced nephrosis rat model fed a high-protein diet that induced renal dysfunction and tubulointerstitial injury. Administration of Adriamycin caused hyperlipidemia, proteinuria, and edema with ascites in rats in 4 weeks. Furthermore, a combination of Adriamycin and a high-protein diet increased plasma creatinine and blood urea nitrogen (BUN) and decreased plasma albumin. Histologically, in Adriamycin-treated rats, marked interstitial cellular infiltration, tubular lumen dilation, and tubular cast formation in the kidney were observed. NO-1886 decreased plasma triglyceride and increased HDL cholesterol in Adriamycin-induced nephrotic rats. NO-1886 treatment reduced plasma creatinine and BUN levels and increased plasma albumin in Adriamycin-treated rats; it also ameliorated the ascites and proteinuria. Histologically, NO-1886-treated rats showed a quantitatively significant preservation of tubulointerstitial lesions. These data suggest that NO-1886 may have a protective effect against Adriamycin-induced nephrosis with tubulointerstitial nephritis in rats by a modification of the plasma lipid disorder.

Flow cytometric assessment of effects of fluvastatin on low-density lipoprotein receptor activity in stimulated T-lymphocytes from patients with heterozygous familial hypercholesterolemia

To test the effects of fluvastatin on low-density lipoprotein (LDL) receptor activity in patients with heterozygous familial hypercholesterolemia, the authors measured LDL receptor activity in stimulated T-lymphocytes prepared from 34 patients before and after treatment with 40 mg fluvastatin daily for 12 weeks. Maximally induced pretreatment LDL receptor activities did not correlate with pretreatment plasma cholesterol levels or with changes in plasma cholesterol levels during treatment, and there were no significant changes in LDL receptor activity during treatment. Barring methodological problems, two explanations are possible. Insofar that LDL receptor activity in lymphocytes reflects LDL receptor activity in the liver, the results suggest that the primary response to treatment with fluvastatin in heterozygous familial hypercholesterolemia (FH) patients is not enhanced LDL receptor activity. Alternatively, fluvastatin increases LDL receptor activity in hepatocytes but has little effect on receptor-dependent lipoprotein catabolism in extrahepatic tissues in vivo.

Fluvastatin: a review of its pharmacology and use in the management of hypercholesterolaemia

Fluvastatin, a member of the group of drugs known as HMG-CoA reductase inhibitors, is used in the treatment of patients with hypercholesterolaemia. In clinical trials in patients with primary hypercholesterolaemia, fluvastatin 20 or 40 mg/day achieved marked reductions from baseline in serum levels of low density lipoprotein (LDL)-cholesterol (19 to 31%) and total cholesterol (15 to 21%), along with modest declines in serum triglyceride levels (1 to 12%) and small increases in high density lipoprotein (HDL)-cholesterol levels (2 to 10%). These beneficial effects on the serum lipid profile were similar to those demonstrated with other HMG-CoA reductase inhibitors, although direct comparative trials are limited. Concomitant administration of fluvastatin plus another lipid-lowering agent, such as a bile acid sequestrant, a fibrate or nicotinic acid, usually reduced serum levels of total cholesterol and LDL-cholesterol by at least a further 5 to 10% from baseline compared with fluvastatin monotherapy. Fluvastatin has a similar tolerability profile to that of other HMG-CoA reductase inhibitors. Gastrointestinal disturbances, which are usually mild and transient, were the most frequently reported adverse events with fluvastatin in clinical trials. Persistent elevation of serum transaminase levels occurred in approximately 1% of fluvastatin recipients, which is similar to the rate for other HMG-CoA reductase inhibitors. Unlike other HMG-CoA reductase inhibitors, which have been infrequently associated with myopathy and rarely with rhabdomyolysis, these events have not been associated with fluvastatin to date, although fluvastatin has not been used as extensively as agents such as lovastatin. HMG-CoA reductase inhibitors other than fluvastatin, when given in combination with drugs such as fibrates, nicotinic acid, cyclosporin or erythromycin, can increase the risk of these potentially serious adverse events. Thus far, myopathy or rhabdomyolysis have not been reported among patients receiving fluvastatin concomitantly with any of these drugs. Therefore, fluvastatin can be given with caution in combination with fibrates, nicotinic acid, cyclosporin or erythromycin. In conclusion, fluvastatin has similar efficacy and tolerability profiles to other HMG-CoA reductase inhibitors, which are among the most effective agents available for treating patients with hypercholesterolaemia. Pharmacoeconomic studies performed to date suggest an advantage for fluvastatin over other HMG-CoA reductase inhibitors, predominantly because of its relatively low acquisition costs (at least in those countries in which the evaluations were conducted). Thus, fluvastatin is effective and well tolerated in patients with hypercholesterolaemia and appears to have an economic advantage over other HMG-CoA reductase inhibitors, primarily as a result of its relatively low acquisition costs.