atorvastatin Lipitor
Relationship between LDL-C and non-HDL-C levels and clinical outcome in the GREek Atorvastatin and Coronary-heart-disease Evaluation (GREACE) Study.

Athyros VG, Mikhailidis DP, Papageorgiou AA, Symeonidis AN, Daskalopoulou SS, Kakafika AI, Pehlivanidis AN, Bouloukos VI, Langer A; GREACE Study Collaborative Group.

Atherosclerosis Unit, Aristotelian University, Hippocration Hospital, Thessaloniki, Greece. athyros med.auth.gr

BACKGROUND: Although available guidelines suggest reducing low-density lipoprotein cholesterol (LDL-C) to below 100 mg/dL (2.6 mmol/L), the importance of target-oriented therapy remains controversial. To assess whether achieving guideline-based targets is of benefit, the relationship between clinical outcomes and lipid levels (baseline and on-study) was evaluated in the GREek Atorvastatin and Coronary-heart-disease Evaluation (GREACE) study. This study demonstrated significant reductions in morbidity and mortality associated with active dose titration of atorvastatin and structured management of dyslipidaemia. METHODS AND RESULTS: Intention-to-treat analysis (Cox proportional hazards model) was used to assess the relationship between lipid values and coronary events. Higher levels of LDL-C at baseline were associated with a greater risk of subsequent events among patients randomized to usual care. Reducing the LDL-C and the non-high density lipoprotein cholesterol (non-HDL-C) level to the National Cholesterol Educational Program (NCEP) Adult Treatment Panel (ATP) III goals required greater doses of atorvastatin for the higher baseline quartile of LDL-C. During the study there was a greater reduction in the risk of coronary heart disease (CHD) events in atorvastatin-treated patients who were in the highest quartile of LDL-C at baseline, after achieving the LDL-C treatment goal, in comparison to the usual care patients in the highest baseline LDL-C quartile. CONCLUSIONS: Achieving the NCEP ATP III LDL-C and non-HDL-C goals by titrating up the dose of atorvastatin was associated with a significant reduction in vascular events in patients with CHD. The greatest benefit was seen in those patients with the highest baseline LDL-C levels.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15383187&dopt=Abstract atorvastatin Lipitor



atorvastatin Lipitor
The effects of high glucose and atorvastatin on endothelial cell matrix production.

McGinn S, Poronnik P, Gallery ED, Pollock CA.

Renal Research Group, Kolling Institute, Royal North Shore Hospital, University of Sydney, NSW, Australia.

BACKGROUND: Statins are known to enhance atherosclerotic plaque stability through influences on extracellular matrix homeostasis. Net matrix production reflects the relative balance of matrix production and degradation through enzymes such as matrix metalloproteinases (MMPs) and their inhibitors, tissue inhibitor of MMP (TIMPs). The effects of statins on endothelial cell production of these parameters following co-exposure with a proatherogenic stimulus such as high glucose are not known. METHODS: Human endothelial cells were exposed for 72 h to 5 mm (control) or 25 mm (high) glucose +/- atorvastatin (1 micromol/l). Extracellular matrix homeostasis was assessed by measuring matrix metalloproteinase (MMP)-2 secretion, tissue inhibitor of MMP (TIMP)-1 and -2 secretion and net collagen IV production. Results were expressed as percentage +/- SEM of control values. RESULTS: Exposure to high glucose increased cellular collagen IV expression to 190.1 +/- 11.7% (P < 0.0001) of control levels. No change in MMP-2 secretion (111.6 +/- 5.2%; P > 0.05) was observed but both TIMP-1 and TIMP-2 expression were increased to 136.3 +/- 6.4% and 144.0 +/- 27.5%, respectively (both P < 0.05). The presence of atorvastatin in high glucose conditions reduced collagen IV expression to 136.1 +/- 20.6%. This was paralleled by increased secretion of MMP-2 to 145.8 +/- 7.8% (P < 0.01), increased TIMP-2 expression to 208.0 +/- 21.3% (P < 0.005 compared with high glucose) but no change in TIMP-1 expression (155.1 +/- 14.6%) compared with high glucose alone. The presence of atorvastatin in control conditions did not affect levels of collagen IV expression (114.5 +/- 13.2%). CONCLUSIONS: Endothelial cell exposure to high glucose was associated with a MMP/TIMP profile that increased extracellular matrix production which was attenuated by concurrent exposure to atorvastatin. Consequently, a mechanism by which the atherosclerotic plaque regression that is observed in patients taking these drugs has been demonstrated.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15384957&dopt=Abstract atorvastatin Lipitor



atorvastatin Lipitor
Circulating adiponectin and resistin levels in relation to metabolic factors, inflammatory markers, and vascular reactivity in diabetic patients and subjects at risk for diabetes.

Shetty GK, Economides PA, Horton ES, Mantzoros CS, Veves A.

Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.

OBJECTIVE: Adiponectin and resistin, two recently discovered adipocyte-secreted hormones, may link obesity with insulin resistance and/or metabolic and cardiovascular risk factors. We performed a cross-sectional study to investigate the association of adiponectin and resistin with inflammatory markers, hyperlipidemia, and vascular reactivity and an interventional study to investigate whether atorvastatin mediates its beneficial effects by altering adiponectin or resistin levels. RESEARCH DESIGN AND METHODS: Associations among vascular reactivity, inflammatory markers, resistin, and adiponectin were assessed cross-sectionally using fasting blood samples obtained from 77 subjects who had diabetes or were at high risk to develop diabetes. The effect of atorvastatin on adiponectin and resistin levels was investigated in a 12-week-long randomized, double-blind, placebo-controlled study. RESULTS: In the cross-sectional study, we confirm prior positive correlations of adiponectin with HDL and negative correlations with BMI, triglycerides, C-reactive protein (CRP), and plasma activator inhibitor (PAI)-1 and report a negative correlation with tissue plasminogen activator. The positive association with HDL and the negative association with PAI-1 remained significant after adjusting for sex and BMI. We also confirm prior findings of a negative correlation of resistin with HDL and report for the first time a positive correlation with CRP. All of these associations remained significant after adjusting for sex and BMI. No associations of adiponectin or resistin with any aspects of vascular reactivity were detected. In the interventional study, atorvastatin decreased lipid and CRP levels, but adiponectin and resistin were not specifically altered. CONCLUSIONS: We conclude that adiponectin is significantly associated with inflammatory markers, in part, through an underlying association with obesity, whereas resistin's associations with inflammatory markers appear to be independent of BMI. Lipid profile and inflammatory marker changes produced by atorvastatin cannot be attributed to changes of either adiponectin or resistin. Copyright 2004 American Diabetes Association

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15451915&dopt=Abstract atorvastatin Lipitor



atorvastatin Lipitor
An HPLC method for the determination of atorvastatin and its impurities in bulk drug and tablets.

Erturk S, Sevinc Aktas E, Ersoy L, Ficicioglu S.

Department of Analytical Chemistry, Faculty of Pharmacy, Istanbul University, Beyazit, 34116 Istanbul, Turkey. serturk yahoo.com

A simple high-performance liquid chromatographic (HPLC) method was developed for the analysis of atorvastatin (AT) and its impurities in bulk drug and tablets. This method has shown good resolution for AT, desfluoro-atorvastatin (DFAT), diastereomer-atorvastatin (DSAT), unknown impurities and formulation excipients of tablets. A gradient reverse-phase HPLC assay was used with UV detection. Some solvent systems prepared using methanol or acetonitrile and water or buffer systems with different pH values were tested. Capacity factors of related substances were calculated at all tested systems. Best resolution has been determined using a Luna C18 column with acetonitrile-ammonium acetate buffer pH 4-tetrahydrofuran (THF) as mobile phase. Samples were eluted gradiently with the mobile phase at flowrate 1.0 ml min(-1) and detected at 248 nm. The proposed method was applied to the determination of impurities and were found to contain 0.057-0.081, 0.072-0.097, 0.608-0.664% of the DFAT, DSAT and total impurity, respectively.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=14656592&dopt=Abstract atorvastatin Lipitor



atorvastatin Lipitor
Absence of interaction between atorvastatin or other statins and clopidogrel: results from the interaction study.

Serebruany VL, Midei MG, Malinin AI, Oshrine BR, Lowry DR, Sane DC, Tanguay JF, Steinhubl SR, Berger PB, O'Connor CM, Hennekens CH.

HeartDrug Research, LLC, Baltimore, MD, USA. Heartdrug aol.com

BACKGROUND: Some, but not all, post hoc analyses have suggested that the antiplatelet effects of clopidogrel are inhibited by atorvastatin. We sought to address this issue prospectively by performing serial measurements of 19 platelet characteristics using conventional aggregometry, rapid analyzers, and flow cytometry. METHODS: The Interaction of Atorvastatin and Clopidogrel Study (Interaction Study) was designed for patients undergoing coronary stenting. All patients (n = 75) received 325 mg of aspirin daily for at least 1 week and 300 mg of clopidogrel immediately prior to stent implantation. They had been taking atorvastatin (n = 25), any other statin (n = 25), or no statin (n = 25) for at least 30 days prior to stenting. The main outcome measure was comparison of platelet biomarkers 4 and 24 hours after clopidogrel administration between study groups. RESULTS: At baseline, patients from both statin groups exhibited diminished platelet aggregation and reduced platelet expression of G-protein-coupled protease-activated thrombin receptor (PAR)-1. There were no significant differences in measured platelet characteristics among the study groups 4 and 24 hours after clopidogrel intake, with the exception of a lower collagen-induced aggregation at 24 hours and a constantly diminished expression of PAR-1 in patients treated with any statin. CONCLUSIONS: Statins in general, and atorvastatin in particular, do not affect the ability of clopidogrel to inhibit platelet function in patients undergoing coronary stenting. These prospective data also suggest that statins may inhibit platelets directly via yet unknown mechanism(s) possibly related to the regulation of the PAR-1 thrombin receptors.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15477442&dopt=Abstract atorvastatin Lipitor



atorvastatin Lipitor
Progesterone abolishes estrogen and/or atorvastatin endothelium dependent vasodilatory effects.

Faludi AA, Aldrighi JM, Bertolami MC, Saleh MH, Silva RA, Nakamura Y, Pereira IR, Abdalla DS, Ramires JA, Sousa JE.

Dante Pazzanese Institute of Cardiology, Sao Paulo, Brazil. afaludi uol.com.br

This double blind randomized placebo controlled study assessed the effects of atorvastatin, estradiol and norethisterone, isolated and in combination, on the lipid profile and on vascular reactivity, in post-menopausal women with hypercholesterolemia and arterial hypertension. Ninety-four women aged 50-65 were selected. All have received dietary counseling (4 weeks), placebo (4 weeks), and drug therapy (12 weeks): 17-beta estradiol 2mg/day (E) (n=17); E + norethisterone acetate 1mg/day (P) (n=18); Atorvastatin 10mg/day (A) (n=20); E + A (n=21) and E + P + A (n=18). All treatment modalities have significantly reduced total cholesterol (TC) (E=8.8%, E + P=10.1%, A=27.9%, A + E=29.4% and E + P + A=35.7%) and LDL-cholesterol (LDL-c) levels (E + P + A=46.6%, E + A=45.9%, A=40.2%, E=20.3%, and E + P=12.1%). As concerns HDL-cholesterol (HDL-c), Groups E and E + A had increases of 15.5% and 13.1%, respectively. The addition of a progesterone compound reduced its concentration (Group E + P=-9.1%, and Group E + P + A=-9.5%). By random, approximately half of the patients in each group were designated to the endothelial function evaluation (brachial artery ultrasound). We observed that in Group A (n=10), in Group E (n=10) and with the association (Group E + A) (n=7), there was a significant increase in the flow-mediated vasodilatation as compared to basal measurements. The addition of a progestin has annulled these benefits. CONCLUSIONS: Atorvastatin has promoted more beneficial effects on TC and LDL-c, whereas estradiol was responsible for an increase in HDL-c. The addition of a progesterone derivative abolished these benefits. Atorvastatin, estradiol or both together improved endothelial function, an effect suppressed by the addition of norethisterone.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15488870&dopt=Abstract atorvastatin Lipitor