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Abaszadeh S, Ahmadipour B, Pirany N, Hassanpour H, Khajali F. Effect of dietary inclusion of atorvastatin, garlic, and dill on growth performance, antioxidant defense, gut, and cardio-pulmonary function, and lipogenesis in broiler chickens. Trop Anim Health Prod 2023; 55:216. [PMID: 37212936 DOI: 10.1007/s11250-023-03639-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Accepted: 05/16/2023] [Indexed: 05/23/2023]
Abstract
In the present study, we evaluated the antihyperlipidemic and antioxidant effects of garlic and dill in comparison with atorvastatin to combat lipogenesis in broiler chickens. A total of 400 1-day-old chicks (Ross 308 strain) were randomly distributed into four experimental diets. Dietary treatments included a control diet, the control diet plus atorvastatin at 20 mg/kg, the control diet plus garlic dry powder (GDP) at 7.5 g/kg, and the control diet plus dill dry powder (DDP) at 7.5 g/kg. Chicks were maintained on experimental diets for 42 days under the recommended environmental conditions set out by the strain management manual. The results showed that weight gain, feed conversion ratio (FCR), and duodenal, jejunal, and ileal dimensions of villi (height, width, and the surface absorptive area) were improved by in-feed atorvastatin, GDP, or DDP when compared to the control (P < 0.05). The inclusion of atorvastatin or phytobiotic products increased circulatory levels of nitric oxide (NO) but decreased circulatory levels of malondialdehyde (MDA), triacylglycerol (TAG), and low-density lipoproteins cholesterol (LDL), with concomitant reductions in the T, R, and S waves amplitudes in the Lead 2 electrocardiogram (ECG) (P < 0.05). Dietary supplements caused an up-regulation of inducible nitric oxide synthase (iNOS), superoxide dismutase 1 (SOD1), and glutathione peroxidase (GPX) but reduced the expression of key hepatic lipogenic enzymes (fatty acid synthase (FAS) and hydroxy-methylglutaryl-CoA reductase (HMGCR) (P < 0.05). In conclusion, feed supplementation with atorvastatin, GDP, or DDP suppressed lipogenesis, enhanced antioxidant response, and improved gut and cardio-pulmonary function in broiler chicks subjected to hypobaric hypoxia.
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Affiliation(s)
- Samira Abaszadeh
- Department of Animal Science, Faculty of Agriculture, Shahrekord University, Shahrekord, 88186 34141, Iran
| | - Behnam Ahmadipour
- Department of Animal Science, Faculty of Agriculture, Shahrekord University, Shahrekord, 88186 34141, Iran.
| | - Nasrollah Pirany
- Department of Animal Science, Faculty of Agriculture, Shahrekord University, Shahrekord, 88186 34141, Iran
| | - Hossein Hassanpour
- Department of Basic Sciences, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran
| | - Fariborz Khajali
- Department of Animal Science, Faculty of Agriculture, Shahrekord University, Shahrekord, 88186 34141, Iran
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Nicol P, Bulin A, Castellanos MI, Stöger M, Obermeier S, Lewerich J, Lenz T, Hoppmann P, Baumgartner C, Fischer J, Steiger K, Haude M, Joner M. Preclinical investigation of neoatherosclerosis in magnesium-based bioresorbable scaffolds versus thick-strut drug-eluting stents. EUROINTERVENTION 2020; 16:e922-e929. [PMID: 32583804 DOI: 10.4244/eij-d-19-00747] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
AIMS Neoatherosclerosis is a frequent finding after implantation of permanent metallic stents. Bioresorbable scaffolds (BRS) are considered to reduce the incidence of neoatherosclerosis owing to their dissolution and consequent vascular restoration. The aim of this study was to evaluate the formation of neoatherosclerosis between magnesium-based BRS and thick-strut metallic drug-eluting stents (DES) in a rabbit model of neoatherosclerosis and in proportion to the effect of high-dose statin medication. METHODS AND RESULTS Fully bioresorbable magnesium scaffolds (BRS, n=45) and thick-strut permanent metallic DES of equivalent geometry and design (n=45) were implanted into the iliac arteries of New Zealand White rabbits (n=45) following endothelial balloon injury and exposure to a cholesterol diet. Endothelialisation was assessed in 12 animals after 35 days using scanning electron microscopy (SEM), showing significantly enhanced re-endothelialisation above struts in the BRS (n=13) compared to DES (n=10). Eleven (11) animals were terminated for baseline assessment after 91 days while the remaining 22 animals were randomised to receive high-dose statin treatment (3 mg/kg) or placebo. BRS-treated vessels showed a significant reduction in foam cell infiltration as a sign of early neoatherosclerosis by histology and OCT when compared to thick-strut DES-treated vessels. Statin treatment resulted in significant reduction of foam cell infiltration in BRS and DES by histology. CONCLUSIONS Our findings suggest reduced neoatherosclerosis formation in magnesium-based BRS relative to thick-strut DES. High-dose statin treatment may be a promising measure to reduce neoatherosclerosis progression, both on its own and in synergy with site-targeted device-based treatment.
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Affiliation(s)
- Philipp Nicol
- Deutsches Herzzentrum München and Deutsches Zentrum für Herz-Kreislaufforschung e.V., Munich, Germany
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Plasma Metabolic Signature of Atherosclerosis Progression and Colchicine Treatment in Rabbits. Sci Rep 2020; 10:7072. [PMID: 32341369 PMCID: PMC7184732 DOI: 10.1038/s41598-020-63306-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 03/30/2020] [Indexed: 01/02/2023] Open
Abstract
Balloon catheter endothelial denudation in New Zealand white rabbits fed high cholesterol diet is a validated atherosclerosis model. Well-characterized in terms of atherosclerosis induction and progression, the metabolic changes associated with the atherosclerosis progression remain indeterminate. Non-targeted metabolomics permits to develop such elucidation and allows to evaluate the metabolic consequences of colchicine treatment, an anti-inflammatory drug that could revert these changes. 16 rabbits underwent 18 weeks of atherosclerosis induction by diet and aortic denudation. Thereafter animals were randomly assigned to colchicine treatment or placebo for 18 weeks while on diet. Plasma samples were obtained before randomization and at 36 weeks. Multiplatform (GC/MS, CE/MS, RP-HPLC/MS) metabolomics was applied. Plasma fingerprints were pre-processed, and the resulting matrixes analyzed to unveil differentially expressed features. Different chemical annotation strategies were accomplished for those significant features. We found metabolites associated with either atherosclerosis progression, or colchicine treatment, or both. Atherosclerosis was profoundly associated with an increase in circulating bile acids. Most of the changes associated with sterol metabolism could not be reverted by colchicine treatment. However, the variations in lysine, tryptophan and cysteine metabolism among others, have shown new potential mechanisms of action of the drug, also related to atherosclerosis progression, but not previously described.
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Baumgartner C, Brandl J, Münch G, Ungerer M. Rabbit models to study atherosclerosis and its complications – Transgenic vascular protein expression in vivo. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2016; 121:131-41. [DOI: 10.1016/j.pbiomolbio.2016.05.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 05/01/2016] [Indexed: 12/30/2022]
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Birnbaum Y, Ye Y. Pleiotropic effects of statins: the role of eicosanoid production. Curr Atheroscler Rep 2012; 14:135-9. [PMID: 22286195 DOI: 10.1007/s11883-012-0232-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Affiliation(s)
- Yochai Birnbaum
- The Department of Medicine, Section of Cardiology, Baylor College of Medicine, Houston, TX 77030, USA.
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Lerakis S, El-Chami MF, Patel AD, Veledar E, Alexopoulos E, Zacharoulis A, Triantafyllou A. Effect of lipid levels and lipid-lowering therapy on restenosis after coronary artery stenting. Am J Med Sci 2006; 331:270-3. [PMID: 16702797 DOI: 10.1097/00000441-200605000-00007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Recent experimental and clinical data suggest that lowering serum lipid levels with statins may prevent or delay the process of restenosis. The purpose of this trial is to determine whether lipid levels relate to restenosis and/or whether statin therapy can prevent or delay the process of restenosis after intracoronary stenting. METHODS One hundred thirty-six patients who underwent single coronary artery stenting from June 1995 to June 1997 in our institution were included in the study. All these patients were followed for at least 9 months (mean 392+/-148 days) for major adverse cardiac events (MACE). We defined as MACE the occurrence of death, myocardial infarction, or need for target lesion revascularization. From this cohort, 103 patients had at least one lipid parameter from the lipid profile evaluated within 2 months from the date of the procedure. Patients who had the stent because of an acute myocardial infarction were included in the study only if their lipid profile was evaluated before or at least 6 weeks after the event. Patients with triglyceride levels above 500 had both triglyceride and low-density lipoprotein cholesterol levels excluded from the statistical analysis. Patients were divided into two groups based on lipid levels: normal (Group I; n=31) and elevated (Group II; n=72). Patient outcomes were also analyzed by statin therapy use. RESULTS There was no significant difference in MACE rates between the two groups when outcomes were analyzed by lipid levels (22.6% versus 20.8% P=0.8). Furthermore, outcomes were analyzed by use of statin therapy (Group III, n=53, on statin versus Group IV, n=50, on no statin). There was also no difference in MACE rates between the two groups (20.8% versus 22%; P=0.8). CONCLUSION The process of restenosis has unique features that differentiate it from atherosclerosis. Although lipid-lowering therapy is crucial in delaying the process of atherosclerosis, its role in the prevention of restenosis is yet to be proven.
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Affiliation(s)
- Stamatios Lerakis
- Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
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Mahfouz MM, Kummerow FA. Atorvastatin reduces the plasma lipids and oxidative stress but did not reverse the inhibition of prostacyclin generation by aortas in streptozotocin diabetic rats. Prostaglandins Other Lipid Mediat 2005; 76:59-73. [PMID: 15967162 DOI: 10.1016/j.prostaglandins.2004.12.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2004] [Revised: 12/09/2004] [Accepted: 12/11/2004] [Indexed: 11/23/2022]
Abstract
The effect of atorvastatin (Lipitor) on diabetes-induced changes in plasma lipids, oxidative stress and the ability of aortic tissues to generate prostacyclin was studied in streptozotocin diabetic rats. In diabetic rats, plasma total cholesterol, triglycerides and serum glucose significantly increased compared to nondiabetic rats. Atorvastatin administration to diabetic rats did not affect hyperglycemia but significantly reduced plasma total cholesterol and triglycerides compared to diabetic rats. The oxidative stress markers urinary isoprostane, liver thiobarbituric acid reactive substances (TBARS) and plasma protein carbonyl content significantly increased in diabetic rats compared to nondiabetic rats. Atorvastatin admnistration to diabetic rats significantly reduced oxidative stress levels compared to diabetic rats, but urinary isoprostane and liver TBARS remained significantly higher than nondiabetic rats. Prostacyclin (PGI(2)) generation by aortic tissues significantly decreased in diabetic rats compared to nondiabetic rats. Atorvastatin administration to diabetic rats did not reverse that inhibition. These results were discussed in the light of the possible effects of hyperglycemia and statins on NAD(P)H-oxidase and cyclooxygenase-2 activities and the genetic difference between rats and other mammals regarding the level of vascular superoxide dismutase (SOD) activity.
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Affiliation(s)
- M M Mahfouz
- University of Illinois, The H. E. Moore Heart Research Foundation Champaign, IL 61820, USA
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Van Doornum S, McColl G, Wicks IP. Atorvastatin reduces arterial stiffness in patients with rheumatoid arthritis. Ann Rheum Dis 2004; 63:1571-5. [PMID: 15547080 PMCID: PMC1754856 DOI: 10.1136/ard.2003.018333] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND Chronic systemic inflammation may contribute to accelerated atherosclerosis and increased arterial stiffness in patients with rheumatoid arthritis (RA). In addition to lowering cholesterol, statins have immunomodulatory effects which may be especially beneficial in patients with RA who have systemic immune activation. OBJECTIVE To investigate the effect of atorvastatin on the augmentation index (AIx: a measure of arterial stiffness) and systemic inflammation in RA. METHODS 29 patients with RA (mean (SD) age 55 (13) years) with moderately active disease of long duration were studied. AIx, lipid levels, serum inflammatory markers, and disease activity score were measured before and after 12 weeks of atorvastatin 20 mg daily. RESULTS AIx improved significantly from 34.1 (11.6)% to 29.9 (11)% (p = 0.0002), with the greatest improvements in AIx occurring in those subjects with the highest disease activity scores (r = -0.5, p = 0.007). Total and LDL cholesterol were reduced from 5.5 (0.9) to 3.9 (0.7) mmol/l and 3.3 (0.8) to 1.9 (0.6) mmol/l, respectively (p = 0.0001). Serum inflammatory markers remained unchanged during the study. CONCLUSIONS Atorvastatin significantly reduced arterial stiffness in patients with RA. The greatest improvements were seen in patients with more active disease, suggesting that, in addition to the beneficial effects of cholesterol reduction, immune modulation may contribute to the cardioprotective effect of statins.
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Affiliation(s)
- S Van Doornum
- Department of Rheumatology, The Royal Melbourne Hospital, Parkville VIC 3050 Australia.
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Kumai T, Oonuma S, Matsumoto N, Takeba Y, Taniguchi R, Kamio K, Miyazu O, Koitabashi Y, Sekine S, Tadokoro M, Kobayashi S. Anti-lipid deposition effect of HMG-CoA reductase inhibitor, pitavastatin, in a rat model of hypertension and hypercholesterolemia. Life Sci 2004; 74:2129-42. [PMID: 14969717 DOI: 10.1016/j.lfs.2003.09.051] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2003] [Accepted: 09/16/2003] [Indexed: 10/26/2022]
Abstract
Since the rat is an atherosclerosis-resistant species, the study of atherosclerosis using rats is limited. The present study was undertaken to develop an atherosclerotic model in rats, to investigate the effect of nitric oxide (NO) inactivation and hyperlipidemia, and to evaluate the effect of pitavastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) inhibitor, on NO inactivation and on hyperlipidemia-induced changes in the cardiovascular system. Four-month-old male spontaneously hypertensive hyperlipidemic rats (SHHR) and Sprague-Dawley (SD) rats were used to study 1) the effect of the period of treatment with N(G)-nitro-L-arginine methyl ester (L-NAME, 100 mg/L) on high fat diet (HFD)-treated SHHR and SD rats, and 2) the effect of pitavastatin (Pit, 0.3 mg/kg/day) on the changes in the aorta of L-NAME- and HFD-treated SHHR and SD rats. L-NAME administration for 1 month then HFD feeding for 2 months markedly increased the deposition of lipids and the thickness of the endothelium in SHHR. Continuous L-NAME treatment with HFD produced severe injury and stripped of endothelium in both strains. The plasma total cholesterol of L-NAME + HFD-treated and L-NAME + HFD + Pit-treated SHHR was significantly higher than that of control SHHR. Lipid deposition, however, was comparatively less in the aorta of L-NAME + HFD + Pit-treated SHHR. The concentration of cholesterol in the aorta of control SHHR was significantly lower than that in the aorta of L-NAME + HFD-treated SHHR, whereas that of L-NAME + HFD + Pit-treated SHHR was the same as that in control SHHR. These data indicated that Pit blocked lipid deposition in the aorta of L-NAME + HFD treated SHHR without changing plasma lipid profiles. In conclusion, NO inactivation and HFD induce lipid deposition in the endothelium, and the HMG-CoA reductase inhibitor blocks the deposition in SHHR.
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Affiliation(s)
- Toshio Kumai
- Department of Pharmacology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae, Kawasaki 216-8511, Japan.
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Herdeg C, Fitzke M, Oberhoff M, Baumbach A, Schroeder S, Karsch KR. Effects of atorvastatin on in-stent stenosis in normo- and hypercholesterolemic rabbits. Int J Cardiol 2003; 91:59-69. [PMID: 12957730 DOI: 10.1016/s0167-5273(02)00588-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND In-stent stenosis is characterized by a prolonged proliferation and inflammatory reactions around the stent struts. Potentially the antiproliferative and lipid-lowering effects of atorvastatin can synergistically limit neointima formation after stenting. METHODS Palmaz-Schatz stents were placed in the iliac arteries of white New Zealand rabbits. One half of the animals was fed an 0.5% hypercholesterolemic diet, the other half was normocholesterolemic. Both groups received either atorvastatin (3 mg/kg bodyweight) daily or placebo (n=10 each in the four groups). After 28 days the segments were excised. RESULTS Injury scores as a result of vessel trauma induced by stent-overstretch injury differed significantly between the four groups (median 1.0-1.9) and the stent-induced injury outweighed the beneficial effects of statin therapy on neointima formation by far. Smooth-muscle-cell proliferation was significantly increased in both hypercholesterolemic groups. Intimal and medial proliferation as well as inflammatory infiltrates around the stent strut were reduced by 20-40% in animals that received statin therapy although the injury score in both statin groups was 19 and 60% higher than in control animals. CONCLUSION Thus, the data of this study indicate that smooth muscle cell proliferation and inflammation in stented vessels can be reduced by atorvastatin both in hypercholesterolemic rabbits and in animals with normal lipid levels.
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Affiliation(s)
- Christian Herdeg
- Department of Medicine, University of Tuebingen, Otfried-Mueller-Strasse 10, D-72076 Tuebingen, Germany.
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Delsing DJM, Jukema JW, van de Wiel MA, Emeis JJ, van der Laarse A, Havekes LM, Princen HMG. Differential effects of amlodipine and atorvastatin treatment and their combination on atherosclerosis in ApoE*3-Leiden transgenic mice. J Cardiovasc Pharmacol 2003; 42:63-70. [PMID: 12827028 DOI: 10.1097/00005344-200307000-00010] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This study was designed to investigate the potential antiatherosclerotic effects of the calcium antagonist amlodipine as compared with the HMG-CoA reductase inhibitor atorvastatin and the combination of both in ApoE*3-Leiden transgenic mice. Four groups of 15 ApoE*3-Leiden mice were put on a high-cholesterol diet. One group received 0.002% (wt/wt) amlodipine in the diet, which had no effect on plasma cholesterol levels. Another group received 0.01% (wt/wt) atorvastatin, resulting in a decrease of plasma cholesterol by 50% by a reduction in very low density lipoprotein production. The combination group received both amlodipine and atorvastatin. After 28 weeks, atherosclerosis in the aortic root was quantified. Treatment with amlodipine had no significant effect on atherosclerotic lesion area, whereas atorvastatin markedly reduced atherosclerosis by 77% compared with the control group. Atorvastatin also reduced inflammation markers. The combination of amlodipine and atorvastatin tended to reduce lesion area by 61% compared with the atorvastatin-only group; however, this effect did not reach statistical significance. Amlodipine treatment significantly reduced calcification in the lesions, whereas atorvastatin alone had no effect. The combination of amlodipine and atorvastatin resulted in a near absence of calcium deposits in the lesions. This study demonstrates that amlodipine treatment alone does not significantly reduce atherosclerotic lesion development. Atorvastatin was shown to have strong antiatherosclerotic effects, and cotreatment with amlodipine may potentiate the antiatherosclerotic effect of atorvastatin.
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van de Poll SWE, Delsing DJM, Jukema JW, Princen HMG, Havekes LM, Puppels GJ, van der Laarse A. Raman spectroscopic investigation of atorvastatin, amlodipine, and both on atherosclerotic plaque development in APOE*3 Leiden transgenic mice. Atherosclerosis 2002; 164:65-71. [PMID: 12119194 DOI: 10.1016/s0021-9150(02)00055-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Raman spectroscopy allows quantitative, non-destructive evaluation of entire, intact atherosclerotic plaques. We quantified the anti-atherosclerotic effects of atorvastatin and amlodipine on progression of atherosclerosis using post-mortem Raman spectroscopic plaque imaging in 28 APOE*3 Leiden transgenic mice who were fed a high fat/high cholesterol diet for 28 weeks. Mice were assigned to a control group receiving the diet alone or to groups that received the diet with either 0.01% w/w atorvastatin, 0.002% w/w amlodipine, or the combination. The entire excised aortic arch was scanned with Raman microspectroscopy for quantitation of the distribution of cholesterol and calcification content. When mice had been treated with atorvastatin, cholesterol accumulation and calcification in the aortic arch was reduced by 91 and 98%, respectively, (both P<0.001). Amlodipine did not reduce the cholesterol content but reduced calcification of the aorta by 69% (P<0.05). The combination of amlodipine and atorvastatin was as effective as atorvastatin alone. This study demonstrates the strong atheroprotective potential of atorvastatin. In addition it is demonstrated that amlodipine reduces mineralization of atherosclerotic plaque. No synergistic effect of the combination of amlodipine and atorvastatin on plaque development is demonstrated. This study encourages Raman spectroscopic evaluations of anti-atherosclerotic drugs in larger animals and humans in vivo.
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Affiliation(s)
- Sweder W E van de Poll
- Department of Cardiology, C5-P, Leiden University Medical Center, P.O. Box 9600, 2300 RC, Leiden, The Netherlands
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Baetta R, Camera M, Comparato C, Altana C, Ezekowitz MD, Tremoli E. Fluvastatin reduces tissue factor expression and macrophage accumulation in carotid lesions of cholesterol-fed rabbits in the absence of lipid lowering. Arterioscler Thromb Vasc Biol 2002; 22:692-8. [PMID: 11950712 DOI: 10.1161/01.atv.0000012802.69414.a8] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The expression of tissue factor (TF), mainly by infiltrated inflammatory cells, has been shown to be responsible for the thrombogenicity associated with atheroma. The contribution of the nonlipid-related effects of statins to the clinical benefits of statin therapy is currently under intense investigation. In this study, we evaluated the ability of fluvastatin to modulate TF expression and macrophage accumulation in rabbit carotid intimal lesions independently of cholesterol lowering. Male rabbits were fed for 30 days a 1% cholesterol-rich diet with or without fluvastatin at 5 mg/kg per day. Two weeks from the start of treatment, a silastic collar was placed around the carotid artery. Fifteen days later, the animals were killed, and carotid segments were excised and processed. The atherogenic diet caused a consistent increase in plasma cholesterol levels (610+/-231 mg/dL versus 50+/-9 mg/dL at baseline), which were not affected by fluvastatin (603+/-248 mg/dL). In the rabbits fed a high cholesterol diet without fluvastatin, an intimal lesion with macrophage accumulation and TF expression was detected. Fluvastatin significantly reduced TF and macrophage content of the lesion (-50% for both). Results indicate that fluvastatin may attenuate the inflammatory and thrombogenic potential of atherosclerotic lesions through a mechanism(s) other than cholesterol reduction, providing new insight regarding the complex mode of action of statins.
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Affiliation(s)
- Roberta Baetta
- Department of Pharmacological Sciences, University of Milan, Milan, Italy
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Malhotra HS, Goa KL. Atorvastatin: an updated review of its pharmacological properties and use in dyslipidaemia. Drugs 2002; 61:1835-81. [PMID: 11693468 DOI: 10.2165/00003495-200161120-00012] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
UNLABELLED Atorvastatin is a synthetic hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitor. In dosages of 10 to 80 mg/day, atorvastatin reduces levels of total cholesterol, low-density lipoprotein (LDL)-cholesterol, triglyceride and very low-density lipoprotein (VLDL)-cholesterol and increases high-density lipoprotein (HDL)-cholesterol in patients with a wide variety of dyslipidaemias. In large long-term trials in patients with primary hypercholesterolaemia. atorvastatin produced greater reductions in total cholesterol. LDL-cholesterol and triglyceride levels than other HMG-CoA reductase inhibitors. In patients with coronary heart disease (CHD), atorvastatin was more efficacious than lovastatin, pravastatin. fluvastatin and simvastatin in achieving target LDL-cholesterol levels and, in high doses, produced very low LDL-cholesterol levels. Aggressive reduction of serum LDL-cholesterol to 1.9 mmol/L with atorvastatin 80 mg/day for 16 weeks in patients with acute coronary syndromes significantly reduced the incidence of the combined primary end-point events and the secondary end-point of recurrent ischaemic events requiring rehospitalisation in the large. well-designed MIRACL trial. In the AVERT trial, aggressive lipid-lowering therapy with atorvastatin 80 mg/ day for 18 months was at least as effective as coronary angioplasty and usual care in reducing the incidence of ischaemic events in low-risk patients with stable CHD. Long-term studies are currently investigating the effects of atorvastatin on serious cardiac events and mortality in patients with CHD. Pharmacoeconomic studies have shown lipid-lowering with atorvastatin to be cost effective in patients with CHD, men with at least one risk factor for CHD and women with multiple risk factors for CHD. In available studies atorvastatin was more cost effective than most other HMG-CoA reductase inhibitors in achieving target LDL-cholesterol levels. Atorvastatin is well tolerated and adverse events are usually mild and transient. The tolerability profile of atorvastatin is similar to that of other available HMG-CoA reductase inhibitors and to placebo. Elevations of liver transaminases and creatine phosphokinase are infrequent. There have been rare case reports of rhabdomyolysis occurring with concomitant use of atorvastatin and other drugs. CONCLUSION Atorvastatin is an appropriate first-line lipid-lowering therapy in numerous groups of patients at low to high risk of CHD. Additionally it has a definite role in treating patients requiring greater decreases in LDL-cholesterol levels. Long-term studies are under way to determine whether achieving very low LDL-cholesterol levels with atorvastatin is likely to show additional benefits on morbidity and mortality in patients with CHD.
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Affiliation(s)
- H S Malhotra
- Adis International Limited, Mairangi Bay, Auckland, New Zealand
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Ferrier KE, Muhlmann MH, Baguet JP, Cameron JD, Jennings GL, Dart AM, Kingwell BA. Intensive cholesterol reduction lowers blood pressure and large artery stiffness in isolated systolic hypertension. J Am Coll Cardiol 2002; 39:1020-5. [PMID: 11897445 DOI: 10.1016/s0735-1097(02)01717-5] [Citation(s) in RCA: 230] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVES We sought to investigate the effects of intensive cholesterol reduction on large artery stiffness and blood pressure in normolipidemic patients with isolated systolic hypertension (ISH). BACKGROUND Isolated systolic hypertension is associated with elevated cardiovascular morbidity and mortality and is primarily due to large artery stiffening, which has been independently related to cardiovascular mortality. Cholesterol-lowering therapy has been efficacious in reducing arterial stiffness in patients with hypercholesterolemia, and thus may be beneficial in ISH. METHODS In a randomized, double-blinded, cross-over study design, 22 patients with stage I ISH received three months of atorvastatin therapy (80 mg/day) and three months of placebo treatment. Systemic arterial compliance was measured noninvasively using carotid applanation tonometry and Doppler velocimetry of the ascending aorta. RESULTS Atorvastatin treatment reduced total and low-density lipoprotein cholesterol and triglyceride levels by 36 +/- 2% (p < 0.001), 48 +/- 3% (p < 0.001) and 23 +/- 5% (p = 0.003), respectively, and increased high density lipoprotein cholesterol by 7 +/- 3% (p = 0.03). Systemic arterial compliance was higher after treatment (placebo vs. atorvastatin: 0.36 +/- 0.03 vs. 0.43 +/- 0.05 ml/mm Hg, p = 0.03). Brachial systolic blood pressure was lower after atorvastatin treatment (154 +/- 3 vs. 148 +/- 2 mm Hg, p = 0.03), as were mean (111 +/- 2 vs. 107 +/- 2 mm Hg, p = 0.04) and diastolic blood pressures (83 +/- 1 vs. 81 +/- 2 mm Hg, p = 0.04). There was a trend toward a reduction in pulse pressure (71 +/- 3 vs. 67 +/- 2 mm Hg, p = 0.08). CONCLUSIONS Intensive cholesterol reduction may be beneficial in the treatment of patients with ISH and normal lipid levels, through a reduction in large artery stiffness.
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Affiliation(s)
- Kathryn E Ferrier
- Alfred and Baker Medical Unit, Baker Medical Research Institute, Melbourne, Victoria, Australia
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17
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Carneado J, Alvarez de Sotomayor M, Perez-Guerrero C, Jimenez L, Herrera MD, Pamies E, Martin-Sanz MDV, Stiefel P, Miranda M, Bravo L, Marhuenda E. Simvastatin improves endothelial function in spontaneously hypertensive rats through a superoxide dismutase mediated antioxidant effect. J Hypertens 2002; 20:429-37. [PMID: 11875310 DOI: 10.1097/00004872-200203000-00018] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Hydroxymethylglutaryl coenzyme A (HMGCoA) reductase inhibitors have beneficial effects beyond their cholesterol-lowering properties. The antioxidant mechanism of HMGCoA reductase inhibitors is not completely understood. OBJECTIVES To elucidate the antioxidant effect of simvastatin. METHODS We studied the influence of simvastatin treatment on the development of hypertension, modification of antioxidant systems, and reactivity of aortic rings in Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats. RESULTS Simvastatin had no effect on blood pressure (BP). Simvastatin treatment (either 1 or 2 mg/kg body weight for 12 or 20 weeks) increased superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities in SHR rats compared with untreated control SHR rats. Carbachol-induced relaxation of aortic rings was impaired in control SHR rats and was restored by simvastatin treatment. Addition of SOD improved the response in control SHR rats and did not have any effect in treated SHR rats. Addition of diethyldithiocarbamic acid, a selective inhibitor of SOD, produced a mild non-significant impairment in carbachol-induced relaxation in control SHR rats, suggesting a deficient antioxidant system in these animals. However, in treated SHR and in WKY rats, impairment of the relaxation was marked, implying that SOD activity in these animals was important to maintain endothelial function. In aortic rings without endothelium from SHR rats, contraction induced by free radicals was substantially higher than in WKY rats. This effect was attenuated in 1-mg-treated rats and abolished in 2-mg-treated rats. CONCLUSIONS Simvastatin promotes intracellular antioxidant systems, fundamentally SOD, restoring endothelial function but not having any effect on blood pressure.
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Affiliation(s)
- Joaquin Carneado
- Hypertension and Lipids Unit, Department of Internal Medicine, Virgen del Rocío University Hospital, Seville, Spain.
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18
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Grip O, Janciauskiene S, Lindgren S. Atorvastatin activates PPAR-gamma and attenuates the inflammatory response in human monocytes. Inflamm Res 2002; 51:58-62. [PMID: 11926313 DOI: 10.1007/bf02684000] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVE To investigate the ability of statins to activate the nuclear receptor peroxisome proliferator-activated receptor gamma (PPAR-gamma) in primary human monocytes in culture. MATERIALS AND METHODS Human peripheral monocytes were incubated with atorvastatin (0.1-10 micromol/1) for up to 24 hours. PPAR-gamma expression was analysed by electrophoretic mobility shift assay. Pro-inflammatory cytokines were measured by enzyme-linked immunosorbent assays, and oxygen consumption was determined polarographically with a Clark-type oxygen electrode. RESULTS We found that atorvastatin activates PPAR-gamma and inhibits the production of tumour necrosis factor-alpha up to 38% (p < 0.05), monocyte chemoattractant protein-1 up to 85% (p < 0.05), and gelatinase B up to 73% (p < 0.05), in a concentration-dependent manner. Moreover, atorvastatin shows concentration-dependent inhibition of cellular oxygen consumption up to 41%. CONCLUSIONS These findings contribute to the growing knowledge of the anti-inflammatory effects of statins, and have led us to the suggestion that statins may control inflammatory responses by the regulation of intracellular lipid homeostasis.
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Affiliation(s)
- O Grip
- Department of Medicine, Lund University, University Hospital MAS, Malmö, Sweden.
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19
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Zelvyte I, Dominaitiene R, Crisby M, Janciauskiene S. Modulation of inflammatory mediators and PPARgamma and NFkappaB expression by pravastatin in response to lipoproteins in human monocytes in vitro. Pharmacol Res 2002; 45:147-54. [PMID: 11846628 DOI: 10.1006/phrs.2001.0922] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Statins are inhibitors of the rate-limiting step of cellular cholesterol synthesis. In vitro and in vivo studies suggest that statins have anti-inflammatory properties independent of their cholesterol-lowering effects. These observations prompted us to examine the effects of pravastatin (50 microM) and native or oxidized low density lipoprotein (nLDL or oxLDL) (50 microg ml(-1)) on primary human monocytes. We found that cells treated with pravastatin prior to nLDL and cells pre-treated with oxLDL prior to pravastatin showed increased activity of peroxisome proliferator-activated receptor gamma (PPAR gamma). Treatment of cells with drug either before incubation with oxLDL or afterwards suppressed nuclear factor kappa B (NF kappa B) expression and reduced uptake of(125)I-oxLDL by 1.7- and 1.5-fold, respectively. Pravastatin also increased PPAR gamma levels and abolished NF kappa B activity in non-stimulated monocytes. Statin added to monocytes prior to or after treatment with nLDL or oxLDL significantly inhibited generation of matrix metalloproteinases (MMPs), monocyte chemotactic protein-1 (MCP-1) and tumor necrosis factor alpha (TNF- alpha). These data corroborate previous findings of the pleiotropic role of statins and also suggest the involvement of transcription factors such as PPAR gamma and NF kappa B in the modulation of the inflammatory processes by statins.
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Affiliation(s)
- Inga Zelvyte
- Department of Medicine, Lund University, University Hospital MAS, S-20502 Malmö, Sweden
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20
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Effects of feeding various tocotrienol sources on plasma lipids and aortic atherosclerotic lesions in cholesterol-fed rabbits. Food Res Int 2002. [DOI: 10.1016/s0963-9969(01)00192-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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21
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Abstract
Normal embryonic development, tissue differentiation and repair in the eukaryote requires a tightly regulated apoptosis, or programmed cell death. Apoptosis also plays an essential role in different pathological processes including atherosclerosis, in which it affects all cell types in the atherosclerotic lesion, including endothelial cells, vascular smooth muscle cells, and macrophages. During atherosclerosis progression, pro- and anti-apoptotic signals abound in the evolving lesion. Apoptosis limits the number of a particular cell type that accumulates in the lesion and slows down the overall progression of the lesion. On the other hand, it contributes to the production of unstable plaques. Many pharmacological agents used to treat cardiovascular and lipid disorders have pro- or/and anti-apoptotic effects. Pharmaceuticals that modulate apoptosis in specific types of cell can potentially serve as anti-atherogenic agents. However, to develop agents for clinical use requires a thorough knowledge of the pathophysiology of apoptosis in atheromatous lesions, a highly cell-specific process. Here we review our current understanding of the process to provide a background for future pharmacological research in the area.
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Affiliation(s)
- N V Guevara
- Department of Physical Science, University of Texas at Brownsville, Brownsville, TX 78520, USA
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22
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Lee CH, Jeong TS, Choi YK, Hyun BH, Oh GT, Kim EH, Kim JR, Han JI, Bok SH. Anti-atherogenic effect of citrus flavonoids, naringin and naringenin, associated with hepatic ACAT and aortic VCAM-1 and MCP-1 in high cholesterol-fed rabbits. Biochem Biophys Res Commun 2001; 284:681-8. [PMID: 11396955 DOI: 10.1006/bbrc.2001.5001] [Citation(s) in RCA: 173] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The anti-atherogenic effects of the citrus flavonoids, naringin and naringenin, were evaluated in high cholesterol-fed rabbits. At 3 months of age, 30 male New Zealand White (NZW) rabbits were divided into three groups (n = 10 per group). The rabbits were fed a 1% cholesterol diet alone (control group) or a diet supplemented with either 0.1% naringin or 0.05% naringenin for 8 weeks. The plasma lipoprotein levels, total cholesterol, triglyceride, and high-density lipoprotein showed no significant differences in the control and experimental groups. Hepatic acyl-CoA:cholesterol acyltransferase (ACAT) activity was slightly low in naringin (5.0%)- and naringenin (15.0%)-fed rabbits, compared to control group. The aortic fatty streak areas were significantly lower in both the naringin (19.2 +/- 5.6%)- and naringenin (18.1 +/- 6.5%)-supplemented groups than in the control group (60.4 +/- 14.0%). The expression levels of vascular cell adhesion molecule-1 (VCAM-1) and monocyte chemotactic protein-1 (MCP-1), by semiquantitative RT-PCR analysis of the thoracic aorta, were significantly lower in the flavonoids supplemented groups than in the control group. These results suggest that the anti-atherogenic effect of the citrus flavonoids, naringin and naringenin, is involved with a decreased hepatic ACAT activity and with the downregulation of VCAM-1 and MCP-1 gene expression.
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Affiliation(s)
- C H Lee
- Genetic Resources Center, Korea Research Institute of Bioscience and Biotechnology, Taejon 305-600, Korea
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23
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Grip O, Janciauskiene S, Lindgren S. Pravastatin down-regulates inflammatory mediators in human monocytes in vitro. Eur J Pharmacol 2000; 410:83-92. [PMID: 11134659 DOI: 10.1016/s0014-2999(00)00870-0] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
There is experimental evidence that pravastatin, which is designed to inhibit the rate-limiting enzyme of cholesterol synthesis, can affect cell metabolism and proliferation. We therefore studied the effects of pravastatin on the generation of inflammatory mediators in non-stimulated and stimulated primary human monocytes in vitro. In our experimental model, pravastatin induced a dose-dependent inhibition of monocyte cholesterol synthesis (up to 67%), up-regulation of low density lipoprotein receptor mRNA (by about 35%) and reduction in intracellular cholesterol accumulation. In parallel, exposure of non-stimulated monocytes to various doses of pravastatin resulted in inhibition of monocyte chemoattractant protein-1 protein expression (up to 15-fold), reduction of tumour necrosis factor alpha (TNF-alpha) levels (up to 2.4-fold) and a total loss of metalloproteinase-9 activity in stimulated cells. Pravastatin at concentrations of 5, 100 and 500 microM caused an inhibition of TNF-alpha-induced cellular oxygen consumption from 2. 4- to 5.5-fold. These data extend the findings of potential anti-inflammatory actions of statins and also suggest the possibility for pravastatin use in a broader spectrum of inflammatory situations.
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Affiliation(s)
- O Grip
- Department of Medicine, Division of Gastroenterology and Hepatology, Lund University, University Hospital MAS, S-20502, Malmö, Sweden.
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24
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Gentile S, Turco S, Guarino G, Sasso CF, Amodio M, Magliano P, Salvatore T, Corigliano G, Agrusta M, De Simone G, Gaeta I, Oliviero B, Torella R. Comparative efficacy study of atorvastatin vs simvastatin, pravastatin, lovastatin and placebo in type 2 diabetic patients with hypercholesterolaemia. Diabetes Obes Metab 2000; 2:355-62. [PMID: 11225965 DOI: 10.1046/j.1463-1326.2000.00106.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Although there is little information from primary or secondary prevention trials on cholesterol-lowering medication in diabetic patients, the reduction of elevated cholesterol is widely recommended for this group. The American Diabetes Association (ADA) recommends drug therapy in diabetic patients if low density lipoprotein (LDL)-cholesterol remains at > 130 mg/dl, or > 100 mg/dl in patients with macroangiopathy, after dietary intervention. When cholesterollowering medication is indicated, the choice of the drug must take into account the other lipid abnormalities that are often present and the need to maintain optimal glycaemic control. In the present study we compared the efficacy and safety of the novel HMG-CoA reductase inhibitor atorvastatin at the dose of 10 mg/day with simvastatin , lovastatin and pravastatin at doses of 10, 20 and 20 mg/day, respectively, and placebo, in type 2 diabetic patients with moderate elevation of LDL-cholesterol with or without elevation of triglycerides. All the quoted agents are enzyme inhibitors effective in lowering LDL-cholesterol in humans. The efficacy endpoints were the mean per cent changes in plasma LDL-cholesterol (primary), total cholesterol, triglycerides, and high-density lipoprotein (HDL)-cholesterol concentrations from baseline to the end of treatment (24 weeks). Atorvastatin at a dose of 10 mg/day produced: (1) a significant reduction in LDL-cholesterol (-37%) in comparison with equivalent doses of simvastatin (-26%), pravastatin (-23%), lovastatin (-21%), and placebo (-1%); (2) HDL-cholesterol increases (7.4%) comparable to or greater than those obtained with simvastatin (7.1%), pravastatin (3.2%), lovastatin (7.21%), and placebo (-0.5%); (3) a significantly greater reduction in total cholesterol (- 29%) than that obtained with simvastatin (-21%), pravastain (-16%), lovastatin (-18%), and placebo (1%); and (4) a significantly greater reduction in triglycerides than that obtained with all the other drugs and placebo. In all treatment groups no significant variation in fibrinogen concentration was observed. All reductase inhibitors studied had similar levels of tolerance. There were no incidents of persistent elevations of serum aminotransferases or myositis.
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Affiliation(s)
- S Gentile
- Department of Geriatrics and Metabolic Diseases, Second University of Naples, Italy.
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25
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Arruzazabala ML, Noa M, Menéndez R, Más R, Carbajal D, Valdés S, Molina V. Protective effect of policosanol on atherosclerotic lesions in rabbits with exogenous hypercholesterolemia. Braz J Med Biol Res 2000; 33:835-40. [PMID: 10881060 DOI: 10.1590/s0100-879x2000000700015] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Policosanol is a mixture of higher aliphatic alcohols purified from sugar cane wax, with cholesterol-lowering effects demonstrable in experimental models and in patients with type II hypercholesterolemia. The protective effects of policosanol on atherosclerotic lesions experimentally induced by lipofundin in rabbits and rats and spontaneously developed in stumptail monkeys have been described. The present study was conducted to determine whether policosanol administered orally to rabbits with exogenous hypercholesterolemia also protects against the development of atherosclerotic lesions. Male New Zealand rabbits weighing 1.5 to 2 kg were randomly divided into three experimental groups which received 25 or 200 mg/kg policosanol (N = 7) orally for 60 days with acacia gum as vehicle or acacia gum alone (control group, N = 9). All animals received a cholesterol-rich diet (0.5%) during the entire period. Control animals developed marked hypercholesterolemia, macroscopic lesions and arterial intimal thickening. Intima thickness was significantly less (32.5 +/- 7 and 25.4 +/- 4 microm) in hypercholesterolemic rabbits treated with policosanol than in controls (57.6 +/- 9 microm). In most policosanol-treated animals, atherosclerotic lesions were not present, and in others, thickness of fatty streaks had less foam cell layers than in controls. We conclude that policosanol has a protective effect on the atherosclerotic lesions occurring in this experimental model.
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Affiliation(s)
- M L Arruzazabala
- Department of Pharmacology, Center of Natural Products, National Center of Scientific Research, Havana, Cuba
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26
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Johnston TP, Baker JC, Hall D, Jamal S, Palmer WK, Emeson EE. Regression of poloxamer 407-induced atherosclerotic lesions in C57BL/6 mice using atorvastatin. Atherosclerosis 2000; 149:303-13. [PMID: 10729380 DOI: 10.1016/s0021-9150(99)00339-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
HMG-CoA reductase inhibitor drugs or 'statins' have been shown to effectively reduce plasma total cholesterol (CHOL), CHOL associated with low-density-lipoprotein (LDL), and triglycerides (TG). In addition, slight elevations in HDL-CHOL are also typically observed. Poloxamer 407 (P-407), a nonionic surfactant, effectively elevates both plasma CHOL and especially TG in a dose-controlled fashion and results in formation of atherosclerotic lesions in the aortas of C57BL/6 mice without the requirement of dietary cholic acid [1,2]. The purpose of the present study was to assess whether a typical statin, namely atorvastatin (Lipitor(R)) would significantly reduce P-407-induced hypercholesterolemia and hypertriglyceridemia as well as cause regression of atherosclerotic lesions resulting from administration of P-407 to C57BL/6 mice. C57BL/6 mice in the present study were treated with either normal saline (C, controls), 0.5 g/kg of P-407 (P), or a high-fat, high-cholesterol, cholate-containing diet (HF) for 120 days. Mice in all groups were then equally and randomly divided and treated with either atorvastatin or saline for an additional 120 days. Beginning at Day 121 and using mice in groups P and HF as an example, one-fourth of the mice in each group received 20 mg/kg per day of atorvastatin with either concomitant HF feeding or P-407 administration ('progression' treatment groups), one-fourth received 20 mg/kg per day of atorvastatin following cessation of HF feeding or P-407 administration, one-fourth received saline (placebo) with either simultaneous HF feeding or P-407 administration ('progression' placebo groups), and one-fourth received saline (placebo) following cessation of HF feeding or P-407 administration. Total plasma CHOL was significantly (P<0.01) lower for mice in groups P and HF when administered atorvastatin relative to saline, but remained significantly (P<0.05) elevated compared to total plasma CHOL of C mice. With discontinuation of either P-407 administration or HF feeding, total plasma CHOL declined rapidly in both P and HF mice with atorvastatin-treated mice generally demonstrating lower plasma CHOL concentrations relative to saline-treated mice. Total plasma TG was significantly (P<0.01) lower for mice in group P administered atorvastatin relative to saline, but remained significantly (P<0.05) elevated compared to plasma TG of C mice. With discontinuation of P-407 administration, total plasma TG declined rapidly in P mice with atorvastatin-treated mice typically demonstrating lower plasma TG concentrations relative to saline-treated P mice. Aortas of mice treated with 20 mg/kg per day of atorvastatin in both groups P and HF, whether maintained on the HF-diet or treated with P-407 from Day 120 to 240 or whether each treatment was terminated at Day 120, revealed no presence of atherosclerotic lesions relative to saline-treated mice and were indistinguishable from aortas retrieved from C mice. Atorvastatin at a dose of 20 mg/kg per day not only significantly reduced the plasma CHOL and TG concentrations, but also resulted in regression of atherosclerotic lesions induced in C57BL/6 mice by administration of P-407 or ingestion of a HF-diet containing cholic acid.
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Affiliation(s)
- T P Johnston
- Division of Pharmaceutical Sciences, Rm. 211A, School of Pharmacy, University of Missouri, 5100 Rockhill Rd., Kansas City, MO 64110-2499, USA.
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Abstract
The beneficial effects of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) on coronary events have generally been attributed to their hypocholesterolaemic properties. However, as mevalonate and other intermediates of cholesterol synthesis (isoprenoids) are necessary for cell proliferation and other important cell functions, effects other than cholesterol reduction may explain the pharmacological properties of statins. In the present review, we discuss the current knowledge on the nonlipid-related effects of statins, with a special emphasis on their potential benefits in different diseases, such as atherosclerosis and cancer. The mechanism(s) responsible for their favourable properties are also reviewed.
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Affiliation(s)
- S Bellosta
- Institute of Pharmacological Sciences, University of Milan, Italy
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28
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Bocan TM, Krause BR, Rosebury WS, Mueller SB, Lu X, Dagle C, Major T, Lathia C, Lee H. The ACAT inhibitor avasimibe reduces macrophages and matrix metalloproteinase expression in atherosclerotic lesions of hypercholesterolemic rabbits. Arterioscler Thromb Vasc Biol 2000; 20:70-9. [PMID: 10634802 DOI: 10.1161/01.atv.20.1.70] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Given the significance of cholesteryl ester (CE) accumulation in macrophage foam cell formation, we hypothesized that inhibitors of acyl-CoA:cholesterol O-acyltransferase (ACAT) would produce a histologically stable lesion by limiting macrophage enrichment and thereby a source of matrix metalloproteinases (MMPs). Male New Zealand White rabbits were sequentially fed a cholesterol/fat diet for 9 weeks, a fat-only diet for 6 weeks, and 25 mg/kg avasimibe for 7 to 8 weeks. Avasimibe had no effect on plasma total cholesterol exposure. Plasma avasimibe maximal concentration and 24-hour area-under-the-curve levels were 178 ng/mL and 2525 ng. h/mL, respectively, after 7 weeks of treatment with 25 mg/kg avasimibe. The median inhibitory concentration against human monocyte-macrophage ACAT was 12 ng/mL when determined in the absence of albumin, and aortic arch avasimibe levels were 25 ng/g of tissue wet weight. Avasimibe reduced thoracic aortic and iliac-femoral CE content by 39%, the extent of thoracic aortic lesions by 41%, aortic arch cross-sectional lesions area by 35%, and monocyte-macrophage area by 27%. The reduction in monocyte-macrophage area reflected a change in cell number and not cell size. In the iliac-femoral artery, avasimibe decreased monocyte-macrophage content by 77% and reduced the macrophage-to-lesion ratio from 0.16 to 0.05. Within the aortic arch, the catalytic activity of latent and active MMP-9 was reduced by 65% and 33%, respectively; latent and active MMP-1 and MMP-3 activity measured collectively was decreased by 52% and 60%, respectively, and MMP-2 was unchanged. Aortic arch MMP-9, tissue inhibitor of matrix metalloproteinase (TIMP)-1, and TIMP-2 mRNA levels were reduced 29% to 39%, and MMP-2 mRNA levels increased. We conclude that the bioavailable ACAT inhibitor avasimibe can directly limit macrophage accumulation, resulting in the histological appearance of mainly fibromuscular lesions, and can potentially stabilize preestablished atherosclerotic lesions by reducing MMP expression within the lesion.
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Affiliation(s)
- T M Bocan
- Departments of Cardiovascular Therapeutics , Parke-Davis Pharmaceutical Research, Division of Warner-Lambert, 2800 Plymouth Rd, Ann Arbor, MI 48105, USA.
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Corsini A, Bellosta S, Baetta R, Fumagalli R, Paoletti R, Bernini F. New insights into the pharmacodynamic and pharmacokinetic properties of statins. Pharmacol Ther 1999; 84:413-28. [PMID: 10665838 DOI: 10.1016/s0163-7258(99)00045-5] [Citation(s) in RCA: 523] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The beneficial effects of statins are assumed to result from their ability to reduce cholesterol biosynthesis. However, because mevalonic acid is the precursor not only of cholesterol, but also of many nonsteroidal isoprenoid compounds, inhibition of 3-hydroxy-3-methylglutaryl coenzyme A reductase may result in pleiotropic effects. It has been shown that several statins decrease smooth muscle cell migration and proliferation and that sera from fluvastatin-treated patients interfere with its proliferation. Cholesterol accumulation in macrophages can be inhibited by different statins, while both fluvastatin and simvastatin inhibit secretion of metalloproteinases by human monocyte-derived macrophages. The antiatherosclerotic effects of statins may be achieved by modifying hypercholesterolemia and the arterial wall environment as well. Although statins rarely have severe adverse effects, interactions with other drugs deserve attention. Simvastatin, lovastatin, cerivastatin, and atorvastatin are biotransformed in the liver primarily by cytochrome P450-3A4, and are susceptible to drug interactions when co-administered with potential inhibitors of this enzyme. Indeed, pharmacokinetic interactions (e.g., increased bioavailability), myositis, and rhabdomyolysis have been reported following concurrent use of simvastatin or lovastatin and cyclosporine A, mibefradil, or nefazodone. In contrast, fluvastatin (mainly metabolized by cytochrome P450-2C9) and pravastatin (eliminated by other metabolic routes) are less subject to this interaction. Nevertheless, a 5- to 23-fold increase in pravastatin bioavailability has been reported in the presence of cyclosporine A. In summary, statins may have direct effects on the arterial wall, which may contribute to their antiatherosclerotic actions. Furthermore, some statins may have lower adverse drug interaction potential than others, which is an important determinant of safety during long-term therapy.
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Affiliation(s)
- A Corsini
- Institute of Pharmacological Sciences, University of Milan, Italy.
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30
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Alfon J, Guasch JF, Berrozpe M, Badimon L. Nitric oxide synthase II (NOS II) gene expression correlates with atherosclerotic intimal thickening. Preventive effects of HMG-CoA reductase inhibitors. Atherosclerosis 1999; 145:325-31. [PMID: 10488960 DOI: 10.1016/s0021-9150(99)00084-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
HMG-CoA reductase inhibitors have been shown to be effective in primary and secondary prevention of coronary heart disease. Their mechanism of action is attributed to their cholesterol lowering activity but recent results seem to indicate additional effects related to the modulation of other processes that regulate the presentation of vascular diseases. Our objective has been to study the effects of atorvastatin and simvastatin, two HMG-CoA reductase inhibitors, on lesion composition and expression of genes involved in lesion development in a diet-induced atherosclerotic rabbit model. Both HMG-CoA reductase inhibitors were administered at identical doses of 2.5 mg/kg per day with the hyperlipemic diet for 10 weeks. Both statins significantly prevented the diet-induced increase in cholesterol levels. Relative lesion composition in fibrinogen, macrophages and smooth muscle cells was unaltered by the treatment although lesion size was reduced; therefore, both HMG-CoA reductase inhibitors reduced total amounts of fibrinogen, macrophages and smooth muscle cells (simvastatin, P < 0.05). NOS II gene expression was positively and significantly correlated with lesion size and inversely correlated with HDL plasma levels. NOS II expression was markedly downregulated in simvastatin treated animals while MCP-1 was unaltered. Therefore, HMG-CoA reductase inhibition seems to interfere with atherosclerotic lesion development by reducing intimal thickening development and the expression of the cytotoxic NOS II.
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Affiliation(s)
- J Alfon
- Cardiovascular Research Center, CSIC-HSCSP-UAB, Barcelona, Spain
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Verd JC, Peris C, Alegret M, Díaz C, Hernández G, Vázquez M, Adzet T, Laguna JC, Sánchez RM. Different effect of simvastatin and atorvastatin on key enzymes involved in VLDL synthesis and catabolism in high fat/cholesterol fed rabbits. Br J Pharmacol 1999; 127:1479-85. [PMID: 10455299 PMCID: PMC1760655 DOI: 10.1038/sj.bjp.0702668] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/1998] [Revised: 03/26/1999] [Accepted: 04/20/1999] [Indexed: 12/14/2022] Open
Abstract
The effects of atorvastatin (3 mg kg(-1)) and simvastatin (3 mg kg(-1)) on hepatic enzyme activities involved in very low density lipoprotein metabolism were studied in coconut oil/cholesterol fed rabbits. Plasma cholesterol and triglyceride levels increased 19 and 4 fold, respectively, after 7 weeks of feeding. Treatment with statins during the last 4 weeks of feeding abolished the progression of hypercholesterolaemia and reduced plasma triglyceride levels. 3-Hydroxy-3-methyl-glutaryl Coenzyme A reductase, acylcoenzyme A:cholesterol acyltransferase, phosphatidate phosphohydrolase and diacylglycerol acyltransferase activities were not affected by drug treatment. Accordingly, hepatic free cholesterol, cholesteryl ester and triglyceride content were not modified. Simvastatin treatment caused an increase (72%) in lipoprotein lipase activity without affecting hepatic lipase activity. Atorvastatin caused a reduction in hepatic phospholipid content and a compensatory increase in CTP:phosphocholine cytidylyl transferase activity. The results presented in this study suggest that, besides the inhibitory effect on 3-hydroxy-3-methyl-glutaryl Coenzyme A reductase, simvastatin and atorvastatin may have additional effects that contribute to their triglyceride-lowering ability.
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Affiliation(s)
- J C Verd
- Unidad de Farmacología y Farmacognosia, Dept. Farmacología y Química Terapéutica, Facultad de Farmacia, Núcleo Universitario de Pedralbes, Barcelona, Spain
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32
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Sliskovic DR, Krause BR, Bocan TM. Chapter 10. Atherosclerosis: Emerging Pharmacological Approaches. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 1999. [DOI: 10.1016/s0065-7743(08)60572-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
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Burnett JR, Barrett PH, Vicini P, Miller DB, Telford DE, Kleinstiver SJ, Huff MW. The HMG-CoA reductase inhibitor atorvastatin increases the fractional clearance rate of postprandial triglyceride-rich lipoproteins in miniature pigs. Arterioscler Thromb Vasc Biol 1998; 18:1906-14. [PMID: 9848883 DOI: 10.1161/01.atv.18.12.1906] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We have previously shown in vivo that the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor atorvastatin decreases hepatic apolipoprotein B (apoB) secretion into plasma. To test the hypothesis that atorvastatin modulates exogenous triglyceride-rich lipoprotein (TRL) metabolism in vivo, an oral fat load (2 g fat/kg body wt) containing retinol (50 000 IU) was given to 6 control miniature pigs and to 6 animals after 28 days of treatment with atorvastatin 3 mg. kg-1. d-1. A multicompartmental model was developed by use of SAAM II and kinetic analysis performed on the plasma retinyl palmitate (RP) data. Peak TRL (d<1.006 g/mL; Sf>20) triglyceride concentrations were decreased 29% by atorvastatin, and the time to achieve this peak was delayed (5.2 versus 2.3 hours; P<0.01). The TRL triglyceride 0- to 12-hour area under the curve was decreased by 24%. In contrast, atorvastatin treatment had no effect on peak TRL RP concentrations, time to peak, or its rate of appearance into plasma; however, the TRL RP 0- to 12-hour area under the curve was decreased by 20%. Analysis of the RP kinetic parameters revealed that the TRL fractional clearance rate was increased significantly, 1.4-fold (3.093 versus 2.276 pools/h; P=0.012), with atorvastatin treatment. The percent conversion of TRL RP from the rapid-turnover to the slow-turnover compartment was decreased by 47% with atorvastatin treatment. The TRL RP fractional clearance rate was negatively correlated with very low density lipoprotein apoB production rate measured in the fasting state (r=-0.49). Thus, although atorvastatin had no effect on intestinal TRL assembly and secretion, plasma TRL clearance was significantly increased, an effect that may relate to a decreased competition for removal processes by hepatic very low density lipoprotein.
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Affiliation(s)
- J R Burnett
- Department of Medicine and The John P. Robarts Research Institute, University of Western Ontario, London, Ontario, Canada
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Guijarro C, Blanco-Colio LM, Ortego M, Alonso C, Ortiz A, Plaza JJ, Díaz C, Hernández G, Egido J. 3-Hydroxy-3-methylglutaryl coenzyme a reductase and isoprenylation inhibitors induce apoptosis of vascular smooth muscle cells in culture. Circ Res 1998; 83:490-500. [PMID: 9734471 DOI: 10.1161/01.res.83.5.490] [Citation(s) in RCA: 265] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recent evidence suggests that apoptosis may be involved in the control of vascular smooth muscle cell (VSMC) number in atherosclerotic lesions. 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors have been reported to induce apoptosis in a variety of tumor cell lines. To evaluate whether these agents also induce apoptosis of VSMCs, cultured rat VSMCs were treated with increasing doses of atorvastatin in the presence of FBS as a survival factor. The presence of apoptosis was evaluated by morphological criteria, annexin V binding, and DNA fragmentation and quantified as the proportion of hypodiploid cells by flow cytometry. Atorvastatin induced apoptosis in a dose-dependent manner, an effect also seen with simvastatin and lovastatin, but not with the hydrophilic drug pravastatin. The proapoptotic effect of statins was seen only when the inhibition of acetate incorporation into sterols was >95% and was fully reversed by mevalonate, farnesyl pyrophosphate, and geranylgeranyl pyrophosphate but not by isopentenyl adenosine, ubiquinone, or squalene, suggesting a role for prenylated proteins in the regulation of VSMC apoptosis. To further assess the role of protein prenylation, VSMCs were exposed to the prenyl transferase inhibitors perillic acid and manumycin A. Both agents induced VSMC apoptosis as evaluated by the above-mentioned criteria. Finally, VSMC treatment with lipophilic statins was associated with decreased prenylation of p21-Rho B, further supporting the role of protein prenylation inhibition in statin-induced VSMC apoptosis. The present data suggest that interference with protein prenylation by HMG-CoA reductase inhibitors or other agents may provide new strategies for the prevention of neointimal thickening.
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Affiliation(s)
- C Guijarro
- Instituto de Investigación Médica, Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Spain
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35
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Krause BR, Princen HM. Lack of predictability of classical animal models for hypolipidemic activity: a good time for mice? Atherosclerosis 1998; 140:15-24. [PMID: 9733211 DOI: 10.1016/s0021-9150(98)00141-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Hypolipidemic drugs that are efficacious in man are not always active in classical animal models of dyslipidemia. Inhibitors of HMG-CoA reductase (statins) do not lower plasma cholesterol in rats, but yet this species was alone in providing activity for fibrate-type drugs. Nicotinic acid possesses many desirable features with regard to clinical use, but most of these actions are lacking in rats and monkeys. The metabolism of low density lipoproteins in hamsters is widely thought to be similar to that in humans, yet neither statins or fibrates lower plasma lipids in these species. With the advent of mouse models expressing specific human genes (or disruption of genes) it is now possible to re-examine the effect of established drugs and to characterize new hypolipidemic compounds with respect to site and mechanism of action. Drug responses observed in humans are now being seen in such mouse models (e.g. HDL elevation with fenofibrate in mice with the human apo A-I gene). Moreover, mice are now being screened for compounds that lower plasma (human) Lp(a), or lower plasma cholesterol in the absence of LDL receptors. It is proposed that these new genetic mouse models may afford a more focused examination of drug action and provide, for new compounds, better prediction of the human response.
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Affiliation(s)
- B R Krause
- Parke-Davis Pharmaceutical Research, Warner-Lambert Company, Ann Arbor, MI 48105, USA.
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36
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Bocan TM, Mueller SB, Brown EQ, Lee P, Bocan MJ, Rea T, Pape ME. HMG-CoA reductase and ACAT inhibitors act synergistically to lower plasma cholesterol and limit atherosclerotic lesion development in the cholesterol-fed rabbit. Atherosclerosis 1998; 139:21-30. [PMID: 9699888 DOI: 10.1016/s0021-9150(98)00046-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Given the beneficial effects of HMG-CoA reductase and ACAT inhibitors on hypercholesterolemia and atherosclerosis, we hypothesized that coadministration would improve the hypolipidemic response and not only limit lesion development but also alter the cellular composition of atherosclerotic lesions so as to induce a stable atherosclerotic lesion morphology. Plasma total cholesterol exposure was reduced 29 and 39% with atorvastatin (2.5 mg/kg) and CI-976 (5 mg/kg), respectively, and 60% upon coadministration due primarily to reductions in VLDL-cholesterol. Modest changes in liver cholesterol ester (CE) content were observed with atorvastatin or CI-976; however, a striking 48% reduction was noted upon coadministration. Liver HMG-CoA reductase mRNA levels were reduced 73% by cholesterol feeding and drug treatment did not prevent the reduction; however, atorvastatin alone and upon coadministration blunted the decrease in LDL receptor mRNA levels. The CE content of the iliac-femoral was unaffected by atorvastatin but was reduced 35% by CI-976 and 53% upon coadministration. Thoracic aortic CE content was reduced 38% by atorvastatin, 48% by CI-976 and 80% upon coadministration. Iliac-femoral lesion and macrophage area were reduced 48 and 67% by atorvastatin, respectively, and 68 and 81% by CI-976 but upon coadministration only an 85% reduction in macrophage area was noted. Aortic arch cross-sectional lesion and macrophage area were unaffected by atorvastatin, decreased 72-80% by CI-976 and reduced 87-92% upon coadministration. We conclude that inhibition of HMG-CoA reductase and ACAT acts synergistically to lower plasma total and lipoprotein cholesterol levels and to limit the development of atherosclerotic lesions in the cholesterol-fed rabbit by presumably regulating cholesterol trafficking pathways within liver and vascular cells.
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Affiliation(s)
- T M Bocan
- Department of Vascular and Cardiac Diseases, Parke-Davis Pharmaceutical Research, Division of Warner Lambert Company, Ann Arbor, MI 48105, USA.
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37
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Kowala MC, Valentine M, Recce R, Beyer S, Goller N, Durham S, Aberg G. Enhanced reduction of atherosclerosis in hamsters treated with pravastatin and captopril: ACE in atheromas provides cellular targets for captopril. J Cardiovasc Pharmacol 1998; 32:29-38. [PMID: 9676717 DOI: 10.1097/00005344-199807000-00005] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase and angiotensin-converting enzyme (ACE) reduce experimental atherosclerosis by different mechanisms. To determine whether dual-drug therapy additively retards the progression of early lesions, control hyperlipidemic hamsters were compared with those treated with pravastatin, captopril, and pravastatin plus captopril. After 8 weeks of treatment, pravastatin (34 mg/kg/day) reduced plasma total cholesterol and triglycerides by 41 and 84%, respectively, whereas captopril (100 mg/kg/day) reduced normal blood pressure by 21%. The combination of pravastatin and captopril (33 and 100 mg/kg/day) decreased plasma total cholesterol and triglycerides by 44 and 84%, and blood pressure was decreased by 14%. In the aortic arch, pravastatin reduced macrophage-foam cell size and fatty streak area by 21 and 31%, respectively, whereas captopril decreased macrophage-foam cell number and fatty streak area by 34 and 35%. Pravastatin plus captopril decreased macrophage-foam cell number, foam cell size, and fatty streak area by 38, 24, and 67%. ACE inhibitors were previously reported to retard atherosclerosis without affecting blood pressure, suggesting that these agents acted on the artery wall. Therefore the expression of arterial ACE was determined in normal and atherosclerotic hamster aortas. ACE messenger RNA (mRNA) and protein were detected in endothelial cells, intimal macrophage-foam cells and medial smooth-muscle cells of atherosclerotic arteries indicating an upregulation of ACE expression with hyperlipidemia and atherosclerosis. In conclusion, dual-therapy with pravastatin and captopril produced an additive reduction in fatty streak area compared with either drug alone and suggested that atherogenesis can be retarded beyond the level achieved with monotherapy. The presence of ACE in endothelial cells and intimal macrophage-foam cells provides cellular targets for captopril to directly modify the formation of early atherosclerotic lesions.
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Affiliation(s)
- M C Kowala
- Department of Cardiovascular Drug Discovery, Bristol-Myers Squibb Pharmaceutical Research Institute, Princeton, New Jersey 08543-4000, USA
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38
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Hernández-Perera O, Pérez-Sala D, Navarro-Antolín J, Sánchez-Pascuala R, Hernández G, Díaz C, Lamas S. Effects of the 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors, atorvastatin and simvastatin, on the expression of endothelin-1 and endothelial nitric oxide synthase in vascular endothelial cells. J Clin Invest 1998; 101:2711-9. [PMID: 9637705 PMCID: PMC508862 DOI: 10.1172/jci1500] [Citation(s) in RCA: 532] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Endothelial dysfunction associated with atherosclerosis has been attributed to alterations in the L-arginine-nitric oxide (NO)-cGMP pathway or to an excess of endothelin-1 (ET-1). The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) have been shown to ameliorate endothelial function. However, the physiological basis of this observation is largely unknown. We investigated the effects of Atorvastatin and Simvastatin on the pre-proET-1 mRNA expression and ET-1 synthesis and on the endothelial NO synthase (eNOS) transcript and protein levels in bovine aortic endothelial cells. These agents inhibited pre-proET-1 mRNA expression in a concentration- and time-dependent fashion (60-70% maximum inhibition) and reduced immunoreactive ET-1 levels (25-50%). This inhibitory effect was maintained in the presence of oxidized LDL (1-50 microg/ml). No significant modification of pre-proET-1 mRNA half-life was observed. In addition, mevalonate, but not cholesterol, reversed the statin-mediated decrease of pre-proET-1 mRNA levels. eNOS mRNA expression was reduced by oxidized LDL in a dose-dependent fashion (up to 57% inhibition), whereas native LDL had no effect. Statins were able to prevent the inhibitory action exerted by oxidized LDL on eNOS mRNA and protein levels. Hence, these drugs might influence vascular tone by modulating the expression of endothelial vasoactive factors.
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Affiliation(s)
- O Hernández-Perera
- Centro de Investigaciones Biológicas, Instituto Reina Sofía de Investigaciones Nefrológicas, Consejo Superior de Investigaciones Científicas, 28006 Madrid, Spain
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Abstract
Atherosclerosis is characterized as a chronic inflammatory-fibroproliferative disease of the vessel wall. The attachment of monocytes and T-lymphocytes to the injured endothelium followed by their migration into the intima is one of the first and most crucial steps in lesion development. The co-localization of CD4+ T-cells and macrophages in the lesion, the abundant expression of HLA Class II molecules and the co-stimulatory molecule CD40 and its ligand (CD40L) indicate a contribution of cell-mediated immunity to atherogenesis. Transgenic mouse models revealed that dependent on the model T- and B-cells may promote lesion progression, monocytes and macrophages are in contrast essential for the development of atherosclerotic lesions. Apart from the local process in the vessel wall, systemic signs of an inflammatory reaction are also associated with lesion development. Thus plasma levels of C-reactive protein and fibrinogen and the white blood cell count are positively correlated to the risk of cardiovascular disease. Recently, an inflammatory phenotype of circulating peripheral blood monocytes could be demonstrated as a specific cellular correlate to lipid and lipoprotein risk factors. Thus the pool size of LPS receptor (CD14)dim and Fc gamma IIIa receptor (CD16a)+ monocytes positively correlates to plasma cholesterol levels, to triglycerides levels and to the apolipoprotein E4 (apo E4) phenotype in contrast to a negative correlation to the high density lipoprotein (HDL) cholesterol concentration. This CD14dim CD16a+ monocytes are further characterized by a high expression of beta 1- and beta 2-integrins, suggesting a higher capacity for attachment at sites of inflammation. A proinflammatory cytokine pattern and an expansion of these cells in other inflammatory diseases are indicating that these cells promote the inflammatory process during atherogenesis. Surface expression of the activation antigen CD45RA on monocytes in correlation to plasma LDL cholesterol and Lp(a) levels further indicates an inflammatory reaction. Regarding the potential mechanisms of the phenotypic changes of peripheral blood monocytes, in a serum free in vitro differentiation model supplemented with M-CSF monocytes from probands which are homozygous for apo E4 showed a significantly higher increase of CD16a expression compared to apo E3/E3 cells indicating that a genetic polymorphism of a single apolipoprotein gene locus may affect monocyte differentiation. The further characterization of the cellular immunology of monocytes and T-lymphocytes in lesion development will provide new specific diagnostic and therapeutic targets in atherogenesis.
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Affiliation(s)
- G Schmitz
- Institute for Clinical Chemistry and Laborary Medicine, University of Regensburg.
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Mohammadi A, Macri J, Newton R, Romain T, Dulay D, Adeli K. Effects of atorvastatin on the intracellular stability and secretion of apolipoprotein B in HepG2 cells. Arterioscler Thromb Vasc Biol 1998; 18:783-93. [PMID: 9598838 DOI: 10.1161/01.atv.18.5.783] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We investigated the effects of atorvastatin, a new 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, on the biogenesis of apolipoprotein B (apoB) in intact and permeabilized HepG2 cells. Intact cells were pretreated either with single or multiple doses of atorvastatin (0.1 to 20 micromol/L) for periods of 6 to 20 hours and pulsed with [35S]methionine. In some cases the cells were permeabilized with digitonin. Experiments were performed to investigate the effects of atorvastatin on (1) the rates of lipid synthesis and secretion, (2) the synthesis and accumulation of apoB, (3) the intracellular stability of apoB, (4) the amount of apoB-containing lipoprotein particles assembled in HepG2 microsomes, and (5) the secretion and accumulation of apoB into the culture medium. ApoB synthesis, degradation, and secretion were measured by pulse-chase experiments with [35S]methionine in both intact and permeabilized HepG2 cells. Lipid synthesis was assessed by pulse-labeling experiments with [3H]acetate or [3H]oleate bound to bovine serum albumin. Comparisons were made under basal conditions and in the presence of oleate (0.36 micromol/L). Atorvastatin acutely inhibited the synthesis of cholesterol and cholesterol ester but did not have a significant effect on triglyceride or phospholipid synthesis. Atorvastatin did not affect the uptake of [35S]methionine by the cells nor did it influence the synthesis of apoB or a control protein, albumin. However, atorvastatin reduced the secretion of apoB into the culture medium, apparently by enhancing the degradation of apoB in the cell under basal and induced conditions with oleate. The stability of apoB associated with the lipoprotein particles was also significantly lowered by atorvastatin. The stimulated degradation of apoB in atorvastatin-treated cells was sensitive to MG132, a proteasome inhibitor. The net effect of atorvastatin was a reduction in the number of apoB-containing lipoprotein particles of different sizes isolated from microsomes and a reduction in apoB secretion into the culture medium. The data suggest that atorvastatin may impair the translocation of apoB into the lumen of the endoplasmic reticulum, thus increasing the amount of apoB degraded intracellularly. It is hypothesized that atorvastatin alters these parameters primarily as a result of inhibiting cholesterol synthesis and limiting the availability of cholesterol and/or cholesterol ester for the normal assembly of apoB-containing lipoprotein particles.
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Affiliation(s)
- A Mohammadi
- Department of Chemistry and Biochemistry, University of Windsor, Ontario, Canada
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Corsini A, Pazzucconi F, Arnaboldi L, Pfister P, Fumagalli R, Paoletti R, Sirtori CR. Direct effects of statins on the vascular wall. J Cardiovasc Pharmacol 1998; 31:773-8. [PMID: 9593078 DOI: 10.1097/00005344-199805000-00017] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The beneficial effects of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) on coronary events have generally been attributed to their hypocholesterolemic properties. Mevalonate and other intermediates of cholesterol synthesis (isoprenoids) are necessary for cell proliferation and other important cell functions; thus effects other than cholesterol reduction may help to explain the antiatherosclerotic properties of statins. Recently we provided in vitro and in vivo evidence of decreased smooth-muscle cell (SMC) proliferation and migration by fluvastatin and simvastatin, but not by pravastatin, independent of plasma cholesterol reduction. The ability of fluvastatin to interfere with arterial SMC proliferation at therapeutic concentrations (0.1-1 microM) prompted us to investigate the pharmacologic activity of sera from 10 patients treated with fluvastatin, 40 mg once daily, on the proliferation of cultured human arterial myocytes. Pravastatin, 40 mg once daily, displays a lipid-lowering activity similar to that of fluvastatin without affecting SMC proliferation and was investigated as a control for assessing this non-lipid-related effect of fluvastatin. Fluvastatin and pravastatin, given for 6 days to patients with type IIa hypercholesterolemia, resulted in a similar decrease in low-density-lipoprotein (LDL) cholesterol. However, the addition of 15% whole-blood sera from patients treated with fluvastatin to the culture medium resulted in a 43% inhibition of cholesterol synthesis in SMCs (p < 0.01) that mirrored the pharmacokinetic profile of fluvastatin. When SMC proliferation was investigated, a significant inhibition of cell growth (-30%; p < 0.01) was detected with sera obtained 6 h after the last dose. No effect on SMC proliferation or cholesterol biosynthesis was observed when sera from patients treated with pravastatin were evaluated. These results suggest that statins exert a direct antiproliferative effect on the arterial wall, beyond their effects on plasma lipids, which could prevent significant cardiovascular disease.
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Affiliation(s)
- A Corsini
- Institute of Pharmacological Sciences, University of Milan, Italy
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Bellosta S, Bernini F, Ferri N, Quarato P, Canavesi M, Arnaboldi L, Fumagalli R, Paoletti R, Corsini A. Direct vascular effects of HMG-CoA reductase inhibitors. Atherosclerosis 1998; 137 Suppl:S101-9. [PMID: 9694549 DOI: 10.1016/s0021-9150(97)00319-5] [Citation(s) in RCA: 162] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Several studies have demonstrated that any beneficial effect of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) on coronary events are linked to their hypocholesterolemic properties. However, since mevalonic acid (MVA), the product of the enzyme reaction, is the precursor of numerous metabolites, inhibition of HMG-CoA reductase has the potential to result in pleiotropic effects. MVA and other intermediates of cholesterol synthesis (isoprenoids) are necessary for cell proliferation and other important cell functions, hence effects other than cholesterol reduction may help to explain the antiatherosclerotic properties of statins. Recently, we provided in vitro evidence that fluvastatin, simvastatin, lovastatin, cerivastatin, but not pravastatin, dose-dependently decrease smooth muscle cells (SMC) migration and proliferation, independently of their ability to reduce plasma cholesterol. Moreover, statins are able to reduce the in vitro cholesterol accumulation in macrophages, by blocking cholesterol esterification and endocytosis of modified lipoproteins. This in vitro inhibition was completely prevented by the addition of mevalonate and partially by all-trans farnesol and all-trans geranylgeraniol, confirming the specific role of isoprenoid metabolites--probably through a prenylated protein(s)--in regulating these cellular events. The inhibitory effect of lipophilic statins on SMC proliferation has been recently shown in different models of proliferating cells such as cultured arterial myocytes and rapidly proliferating carotid and femoral intimal lesions in rabbits. Finally, ex vivo studies recently showed that sera from fluvastatin-treated patients interfere with smooth muscle cell proliferation. These results suggest that HMG-CoA reductase inhibitors exert a direct antiatherosclerotic effect in the arterial wall, beyond their effects on plasma lipids, that could translate into a more significant prevention of cardiovascular disease.
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Affiliation(s)
- S Bellosta
- Institute of Pharmacological Sciences, University of Milan, Milano, Italy
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43
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Dallongeville J, Fruchart JC, Maigret P, Bertolini S, Bon GB, Campbell MM, Farnier M, Langan J, Mahla G, Pauciullo P, Sirtori C. Double-Blind Comparison of Apolipoprotein and Lipoprotein Particle Lowering Effects of Atorvastatin and Pravastatin Monotherapy in Patients With Primary Hypercholesterolemia. J Cardiovasc Pharmacol Ther 1998; 3:103-110. [PMID: 10684487 DOI: 10.1177/107424849800300202] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
METHODS AND RESULTS: A total of 305 subjects with primary hypercholesterolemia were randomized in a 3:1 ratio to receive either atorvastatin 10 mg daily or pravastatin 20 mg daily according to a 16-week double-blind comparative study of the effect on apolipoprotein and lipoprotein particle levels. All patients had low-density lipoprotein (LDL)-cholesterol levels between 4.2 and 6.6 mM and triglyceride concentrations below 4.5 mM at baseline. After 16 weeks of treatment, apoB (-27% and -16%; P <.001), apoE (-13.3% and -5.6%; P <.05) and the triglyceride-rich LpC-III:B particle (-33% and -26%; P <.05) levels were reduced to a significantly greater extent in the atorvastatin than in the pravastatin treatment group. Both atorvastatin and pravastatin increased apoA-I levels, an effect that was more pronounced in the pravastatin group (+7% and +11%; P <.002). The increased apoA-I levels predominated on LpA-I in the atorvastatin group (+11%) and on LpA-I:A-II in the pravastatin group (+13%). ApoA-II levels were decreased with atorvastatin to a greater extent than with pravastatin (-1% and +2.8%; P <.05). CONCLUSIONS: Although atorvastatin and pravastatin belong to the same therapeutic family, they produce different effects in apoliprotein concentrations in hypercholesterolemic patients. Atorvastatin, an agent of the new generation, appears to efficiently reduce apoB-containing lipoprotein particles containing apoC-III.
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44
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Bocan TM, Rosebury WS, Mueller SB, Kuchera S, Welch K, Daugherty A, Cornicelli JA. A specific 15-lipoxygenase inhibitor limits the progression and monocyte-macrophage enrichment of hypercholesterolemia-induced atherosclerosis in the rabbit. Atherosclerosis 1998; 136:203-16. [PMID: 9543090 DOI: 10.1016/s0021-9150(97)00204-9] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Oxidant signalling and lipoprotein oxidation may play important roles in atherosclerotic lesion development. Given coincident localization of 15-lipoxygenase (15-LO), stereospecific products of 15-LO and epitopes of modified LDL in atherosclerotic lesions, we hypothesized that inhibition of 15-LO by PD146176, an inhibitor of 15-LO with an IC50 in cells or isolated enzyme of 0.5-0.8 microM, may limit atherosclerotic lesion development through regulation of monocyte-macrophage enrichment. Rabbits exposed to chronic endothelial denudation of the iliac-femoral artery were meal-fed a 0.25% cholesterol (C), 3% peanut oil (PNO), 3% coconut oil (CNO) diet twice daily with and without 175 mg/kg PD146176 for 12 weeks. In a second study, atherosclerotic lesions were pre-established in rabbits through chronic endothelial denudation and meal-fed a 0.5% C, 3% PNO, 3% CNO diet for 9 weeks and a 0% C/fat diet for 6 weeks prior to an 8 week administration of PD146176 at 175 mg/kg, q.d. Plasma total and lipoprotein cholesterol exposure were similar in control and PD146176-treated animals in both studies but PD146176 increased plasma triglyceride exposure 2- to 4-fold. Plasma PD146176 concentrations ranged from 99 to 214 ng/ml at 2 h post-dose. In the progression study, the iliac-femoral monocyte-macrophage area was reduced 71%, cross-sectional lesion area was unchanged and cholesteryl ester (CE) content was reduced 63%. In the regression study, size and macrophage content of iliac-femoral, fibrous plaque-like lesions were decreased 34%, CE content was reduced 19% and gross extent of thoracic aortic lesions were reduced 41%. We conclude that PD146176 can limit monocyte macrophage enrichment of atherosclerotic lesions and can attenuate development of fibrofoamy and fibrous plaque lesions in the absence of changes in plasma total or lipoprotein cholesterol concentrations.
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Affiliation(s)
- T M Bocan
- Department of Vascular and Cardiac Diseases, Parke-Davis Pharmaceutical Research, Division of Warner Lambert Company, Ann Arbor, MI 48105, USA.
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45
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Bergstrom JD, Bostedor RG, Rew DJ, Geissler WM, Wright SD, Chao YS. Hepatic responses to inhibition of 3-hydroxy-3-methylglutaryl-CoA reductase: a comparison of atorvastatin and simvastatin. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1389:213-21. [PMID: 9512650 DOI: 10.1016/s0005-2760(97)00182-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We have compared the cellular responses to simvastatin (Simva) and atorvastatin (Atorva), two potent HMG-CoA reductase inhibitors. The two drugs exhibited similar IC50's for inhibition of either rat or human reductase, and single oral dosing in rats showed the compounds to be nearly equipotent at inhibiting hepatic cholesterol synthesis. Treatment of rats with Simva or Atorva in the feed for four days yielded comparable inductions of hepatic reductase activity and reductase protein. For example, 0.05% Simva induced reductase activity 27.3 +/- 9.1 fold and 0.05% Atorva induced activity 26.9 +/- 4.7 fold. This adaptive response was also studied in HepG2 cells, a human hepatoblastoma line, cultured for 24 h in delipidated serum and then for an additional 24 h with Simva or Atorva. Over a broad range (10 nM-10 microM), both drugs caused similar inductions of reductase activity, reductase protein, and reductase mRNA. Under all conditions, the drugs induced similar changes in the ratio of mRNA/protein suggesting that Simva and Atorva have similar effects on both transcriptional and post-transcriptional regulatory machinery. Moreover, reductase in cells treated with Simva or Atorva for 22 h responded similarly to subsequent challenge with 25-hydroxycholesterol. Finally, we measured the ability of the two reductase inhibitors to reduce ApoB secretion by HepG2 cells. Simva and Atorva at 0.5 microM inhibited ApoB secretion nearly identically, 38% and 42% respectively. We conclude that these two drugs induce similar adaptive responses in cells and that their actions are qualitatively and mechanistically identical. Human studies have shown that plasma is cleared of Atorva much more slowly than it is of Simva. The large pharmacokinetic difference in man, rather than some difference in mechanism, is the most likely explanation for the finding that the equipotent dose ratio for cholesterol lowering in humans of Simva to Atorva is about 2/1.
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Affiliation(s)
- J D Bergstrom
- Department of Biochemistry, Merck Research Laboratories, Rahway, NJ 07065-0900, USA.
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46
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Burnett JR, Wilcox LJ, Telford DE, Kleinstiver SJ, Barrett PH, Newton RS, Huff MW. Inhibition of HMG-CoA reductase by atorvastatin decreases both VLDL and LDL apolipoprotein B production in miniature pigs. Arterioscler Thromb Vasc Biol 1997; 17:2589-600. [PMID: 9409231 DOI: 10.1161/01.atv.17.11.2589] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In the present studies, the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor atorvastatin was used to test the hypothesis that inhibition of cholesterol biosynthesis in vivo with a consequent reduction in the availability of hepatic cholesterol for lipoprotein synthesis, would (1) reduce very low density lipoprotein (VLDL) apolipoprotein B (apoB) secretion into the plasma, (2) reduce the conversion of VLDL apoB to LDL apoB, and (3) reduce LDL apoB direct synthesis. ApoB kinetic studies were carried out in six control miniature pigs and in six animals after 21 days of administration of atorvastatin (3 mg/kg per day). Pigs were fed a fat- (34% of calories; polyunsaturated to monounsaturated to saturated ratio, 1:1:1) and cholesterol- (400 mg/d cholesterol; 0.1%; 0.2 mg/kcal) containing pig chow-based diet. Atorvastatin treatment significantly reduced plasma total cholesterol, LDL cholesterol, total triglyceride, and VLDL triglyceride concentrations by 16%, 31%, 19%, and 28%, respectively (P < .01). Autologous 131I-VLDL, 125I-LDL, and [3H]leucine were injected simultaneously into each pig, and apoB kinetic data were analyzed using multicompartmental analysis (SAAM II). The VLDL apoB pool size decreased by 29% (0.46 versus 0.65 mg/kg; P = .002), which was entirely due to a 34% reduction in the VLDL apoB production rate (PR) (1.43 versus 2.19 mg/kg per hour; P = .027). The fractional catabolic rate (FCR) was unchanged. The LDL apoB pool size decreased by 30% (4.74 versus 6.75 mg/kg; P = .0004), which was due to a 22% reduction in the LDL apoB PR (0.236 versus 0.301 mg/kg per hour; P = .004), since the FCR was unchanged. The reduction in LDL apoB PR was primarily due to a 34% decrease in conversion of VLDL apoB to LDL apoB; however, this reduction was not statistically significant (P = .114). Hepatic apoB mRNA abundance quantitated by RNase protection assay was decreased by 13% in the atorvastatin-treated animals (P = .003). Hepatic and intestinal LDL receptor mRNA abundances were not affected. We conclude that inhibition of hepatic HMG-CoA reductase by atorvastatin reduces both VLDL and LDL apoB concentrations, primarily by decreasing apoB secretion into the plasma and not by an increase in hepatic LDL receptor expression. This decrease in apoB secretion may, in part, be due to a reduction in apoB mRNA abundance.
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MESH Headings
- Animals
- Anticholesteremic Agents/pharmacology
- Apolipoproteins B/biosynthesis
- Apolipoproteins B/blood
- Apolipoproteins B/genetics
- Apolipoproteins B/metabolism
- Atorvastatin
- Cholesterol/biosynthesis
- Cholesterol/blood
- Depression, Chemical
- Dietary Fats/administration & dosage
- Female
- Gene Expression Regulation/drug effects
- Heptanoic Acids/pharmacology
- Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology
- Intestine, Small/drug effects
- Intestine, Small/metabolism
- Kinetics
- Lipoproteins, LDL/biosynthesis
- Lipoproteins, LDL/blood
- Lipoproteins, VLDL/biosynthesis
- Lipoproteins, VLDL/blood
- Liver/drug effects
- Liver/metabolism
- Male
- Models, Biological
- Pyrroles/pharmacology
- RNA, Messenger/biosynthesis
- Receptors, LDL/biosynthesis
- Receptors, LDL/genetics
- Swine
- Swine, Miniature
- Triglycerides/blood
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Affiliation(s)
- J R Burnett
- Department of Medicine, University of Western Ontario, London, Canada
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47
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Marais AD, Naoumova RP, Firth JC, Penny C, Neuwirth CK, Thompson GR. Decreased production of low density lipoprotein by atorvastatin after apheresis in homozygous familial hypercholesterolemia. J Lipid Res 1997. [DOI: 10.1016/s0022-2275(20)37137-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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48
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Sakai M, Kobori S, Matsumura T, Biwa T, Sato Y, Takemura T, Hakamata H, Horiuchi S, Shichiri M. HMG-CoA reductase inhibitors suppress macrophage growth induced by oxidized low density lipoprotein. Atherosclerosis 1997; 133:51-9. [PMID: 9258407 DOI: 10.1016/s0021-9150(97)00118-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors ameliorate atherosclerotic diseases in several models of vascular disease. This is largely due to their ability to reduce plasma cholesterol levels in vivo. Proliferation of cellular components is one of the major events in the development and progression of atherosclerotic lesions. We recently demonstrated that oxidized low density lipoprotein (Ox-LDL), a likely atherogenic lipoprotein present in vivo, is capable of inducing macrophage growth in vitro. In the present study, we investigated the effect of HMG-CoA reductase inhibitors, simvastatin and pravastatin, on Ox-LDL-induced macrophage growth. Our results demonstrated that these inhibitors effectively suppressed Ox-LDL-induced macrophage growth with concentrations required for 50% inhibition by simvastatin and pravastatin being 0.1 and 80 microM, respectively, and that this inhibitory effect was reversed by mevalonate but not by squalene. Under these conditions, simvastatin did not affect the endocytic degradation of Ox-LDL, nor subsequent accumulation of intracellular cholesteryl esters. Our results suggest that a non-cholesterol metabolites(s) of mevalonate pathway may play an important role in Ox-LDL-induced macrophage growth. Since it is well known that macrophage-derived foam cells are the key cellular element in the early stage of atherosclerosis, a significant inhibition of Ox-LDL-induced macrophage growth by HMG-CoA reductase inhibitors in vitro, particularly simvastatin, may also explain, at least in part, their anti-atherogenic action in vivo.
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Affiliation(s)
- M Sakai
- Department of Metabolic Medicine, Kumamoto University School of Medicine, Japan
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49
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Lea AP, McTavish D. Atorvastatin. A review of its pharmacology and therapeutic potential in the management of hyperlipidaemias. Drugs 1997; 53:828-47. [PMID: 9129869 DOI: 10.2165/00003495-199753050-00011] [Citation(s) in RCA: 200] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Atorvastatin is a synthetic HMG-CoA reductase inhibitor which lowers plasma cholesterol levels by inhibiting endogenous cholesterol synthesis. It also reduces triglyceride levels through an as yet unproven mechanism. Dose-dependent reductions in total cholesterol, low density lipoprotein (LDL)-cholesterol and triglyceride levels have been observed with atorvastatin in patients with hypercholesterolaemia and in patients with hypertriglyceridaemia. In large trials involving patients with hypercholesterolaemia, atorvastatin produced greater reductions in total cholesterol, LDL-cholesterol, apolipoprotein B and triglyceride levels than lovastatin, pravastatin and simvastatin. In patients with primary hypercholesterolaemia, the combination of atorvastatin and colestipol tended to produce larger reductions in LDL-cholesterol levels and smaller reductions in triglyceride levels than atorvastatin monotherapy. Although atorvastatin induced smaller reductions in triglyceride levels and more modest increases in high density lipoprotein (HDL)-cholesterol levels than either fenofibrate or nicotinic acid in patients with combined hyperlipidaemia, it produced larger reductions in total cholesterol and LDL-cholesterol. As with other HMG-CoA reductase inhibitors, the most frequently reported adverse events associated with atorvastatin are gastrointestinal effects. In comparative trials, atorvastatin had a similar adverse event profile to that of other HMG-CoA reductase inhibitors. Clinical data with atorvastatin are limited at present. However, with its ability to markedly reduce LDL-cholesterol levels, atorvastatin is likely to join other members of its class as a first-line agent for the treatment of patients with hypercholesterolaemia, if changes in lipid levels with atorvastatin convert to reductions in CHD mortality and morbidity. Atorvastatin may be particularly suitable for patients with heterozygous or homozygous familial hypercholesterolaemia because of the marked reductions in LDL-cholesterol experienced with the drug. Additionally, because of its triglyceride-lowering properties, atorvastatin appears to have the potential to become an appropriate treatment for patients with combined hyperlipidaemia or hypertriglyceridaemia.
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Affiliation(s)
- A P Lea
- Adis International Limited, Auckland, New Zealand
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50
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Igarashi M, Takeda Y, Mori S, Ishibashi N, Komatsu E, Takahashi K, Fuse T, Yamamura M, Kubo K, Sugiyama Y, Saito Y. Suppression of neointimal thickening by a newly developed HMG-CoA reductase inhibitor, BAYw6228, and its inhibitory effect on vascular smooth muscle cell growth. Br J Pharmacol 1997; 120:1172-8. [PMID: 9134232 PMCID: PMC1564576 DOI: 10.1038/sj.bjp.0701018] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
1. The aim of this study was to determine whether BAYw6228 (BAYw), a newly developed 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitor, could suppress an atherogenic process such as intimal thickening by a mechanism other than lowering the level of serum cholesterol. 2. First, we evaluated the in vitro effect of BAYw on the proliferation of vascular smooth muscle cells (SMC) from various species: Sprague-Dawley (SD) rats. New Zealand (NZ) white rabbits, intimal cells from Watanabe hereditary hyperlipidemic (WHHL) rabbit and SMC from the new-born human aorta. The increasing rate of total protein content of these cells was inhibited by the addition of BAYw in a dose-dependent fashion. In the presence of 2% foetal calf serum (FCS), the value of IC50 was 1.0 microM in SD rats, 2.1 microM in NZ white rabbits, and 0.3 microM in WHHL rabbits. With human SMC, the value was 0.02 microM in the presence of 10% FCS and 0.2 microM with a mixture of growth factors. 3. Based on these above in vitro findings, we next examined the in vivo effect of the agent to determine whether it could suppress rabbit intimal thickening induced by balloon catheterization. A balloon catheter was inserted from a peripheral branch of the left external carotid artery to the aorta to denude the endothelium of the left common carotid artery in Japanese white rabbits. After 12 days they were divided into control and BAYw groups. The former were subcutaneously injected with saline and the latter with BAYw 1 mg kg-1 day-1. Two days after the beginning of treatment, a second balloon injury was performed to the previously injured left common carotid artery in both groups. After another two weeks, the left common carotid artery was removed and variously stained. Although the total serum cholesterol in the BAYw group was significantly lower than in the control (P < 0.05), the difference was not enough to affect intimal thickening. In addition, the BAYw group had a smaller intima/media ratio than the control group, decreasing to 45% of control (P < 0.05). By anti-alpha smooth muscle actin antibody staining, these intimal thickening areas were entirely occupied by SMCs, and their amount was attenuated by BAYw. By anti-rabbit macrophage antibody (RAM 11) staining, the number of positive cells in the intimal thickening was markedly decreased in the BAYw group compared to control (P < 0.01). 4. These results indicate that BAYw has an inhibitory effect on intimal thickening by attenuating intimal SMC proliferation and infiltration of macrophages, suggesting that BAYw could be effective in the prevention of the progression of atherosclerotic plaque-like restenosis after angioplasty.
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Affiliation(s)
- M Igarashi
- Department of Laboratory Medicine, Yamagata University School of Medicine, Japan
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