Effect of atorvastatin on different fibrinolyis mechanisms in hypercholesterolemic subjects

HMG-CoA reductase inhibitors and the attenuation of risk for disseminated intravascular coagulation in patients with sepsis

BACKGROUND

Disseminated Intravascular Coagulation (DIC) is a syndrome of dysregulated coagulation. Patients with sepsis are at increased risk for DIC. HMG-CoA Reductase Inhibitors (Statins) are primarily used as lipid-lowering agents; however, studies have suggested statins may possess anti-inflammatory, antithrombotic, anticoagulant, and endothelial stabilizing properties. These mechanisms may oppose those that underlie the pathogenesis of septic DIC.

METHODS

To evaluate whether statins may be protective against the development of DIC, we conducted a multi-center, retrospective case-control study where 86,638 critically ill patients admitted to the ICU with sepsis, severe sepsis or septic shock were identified during a 3-year period. Patients who developed DIC during their hospitalization were identified and stratified by whether they received a statin or not during their hospitalization. Odds ratios for development of DIC was calculated by composite of any statin, as well as low, moderate, and high intensity statins.

RESULTS

2236 patients would develop DIC compared to 84,402 who did not. The use of any statin was associated with a reduced likelihood for developing DIC (odds ratio [OR], 0.69; 95% CI, 0.61-0.78). This was observed with use of both moderate (OR, 0.64; 95% CI, 0.53-0.77) and high (OR, 0.72; 95% CI, 0.61-0.84) but not low intensity statins (OR, 0.84; 95% CI, 0.53-1.32).

CONCLUSIONS

The use of moderate and high intensity statins was associated with a significantly reduced odds of developing DIC in critically ill patients with sepsis. This present study may be the first to suggest that statin medications may independently reduce the frequency of DIC in critically ill patients with severe sepsis or septic shock. More research is needed to investigate the potential for this class of medication to be protective against DIC.

Effects of proprotein convertase subtilisin-kexin type 9 inhibitors on inflammatory and hemostatic parameters in post myocardial infarction patients

Despite progress in treatment, elevated levels of low-density lipoprotein cholesterol (LDL-C) and lipoprotein (a) (Lp(a)), represent a significant part of the residual risk. Both are associated with inflammation and the coagulation fibrinolytic system. The purpose of our research was to evaluate the effect of proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) on lipid parameters and indicators of inflammation, coagulation and fibrinolysis. We included 100 post myocardial infarction (MI) patients with insufficiently controlled LDL-C values despite the maximum dose of statin, and highly elevated Lp(a). Patients received alirocumab or evolocumab (150 mg sc or 140 mg sc every two weeks, respectively), or placebo for 6 months. In patients receiving PCSK9i, a significant decrease in total cholesterol (TC), LDL-C, triglycerides (TG) and Lp(a), and an increase in high density lipoprotein cholesterol (p < 0.001 for all) was found. Before treatment, the concentrations of TC, LDL-C and TG correlated with the concentrations of thrombin activatable fibrinolysis inhibitor (r = 0.41, p < 0.001; r = 0.353, p < 0.001; r = 0.311, p = 0.003, respectively), and plasminogen activator inhibitor-1 (r = 0.302, p = 0.007; r = 0.218, p = 0.049; r = 0.278; p = 0.013, respectively). The concentrations of TC and LDL-C correlated with overall fibrinolytic potential (r = -0.220, p = 0.034; r = -0.207, p = 0.047, respectively). The concentration of TG was related to the concentration of interleukin 6 (r = 0.290, p = 0.004) and interleukin 8 (r = 0.332, p = 0.001). No correlations between Lp(a) and inflammatory or hemostatic variables were found. No associations were found after treatment. Our results show that inflammatory cytokines and fibrinolytic parameters are related to LDL-C and not Lp(a) in post-MI patients before and with neither of them following PCSK9i treatment. The trial registration number: NCT04613167, Date of registration: November 3, 2020.

Pleiotropic Effects of Atorvastatin Result in a Downregulation of the Carboxypeptidase U System (CPU, TAFIa, CPB2) in a Mouse Model of Advanced Atherosclerosis

Statins (hydroxymethyl-glutaryl-CoA-reductase inhibitors) lower procarboxypeptidase U (proCPU, TAFI, proCPB2). However, it is challenging to prove whether this is a lipid or non-lipid-related pleiotropic effect, since statin treatment decreases cholesterol levels in humans. In apolipoprotein E-deficient mice with a heterozygous mutation in the fibrillin-1 gene (ApoE^−/−Fbn1^C1039G+/−), a model of advanced atherosclerosis, statins do not lower cholesterol. Consequently, studying cholesterol-independent effects of statins can be achieved more straightforwardly in these mice. Female ApoE ^−/−Fbn1C^1039G+/− mice were fed a Western diet (WD). At week 10 of WD, mice were divided into a WD group (receiving WD only) and a WD + atorvastatin group (receiving 10 mg/kg/day atorvastatin +WD) group. After 15 weeks, blood was collected from the retro-orbital plexus, and the mice were sacrificed. Total plasma cholesterol and C-reactive protein (CRP) were measured with commercially available kits. Plasma proCPU levels were determined with an activity-based assay. Total plasma cholesterol levels were not significantly different between both groups, while proCPU levels were significantly lower in the WD + atorvastatin group. Interestingly proCPU levels correlated with CRP and circulating monocytes. In conclusion, our results confirm that atorvastatin downregulates proCPU levels in ApoE^−/−Fbn1^C1039G+/− mice on a WD, and evidence was provided that this downregulation is a pleiotropic effect of atorvastatin treatment.

Effect of Statin Therapy on the Carboxypeptidase U (CPU, TAFIa, CPB2) System in Patients With Hyperlipidemia: A Proof-of-concept Observational Study

PURPOSE

Statins are commonly used in patients with hypercholesterolemia to lower their cholesterol levels and to reduce their cardiovascular risk. There is also considerable evidence that statins possess a range of cholesterol-independent effects, including profibrinolytic properties. This pilot study aimed to explore the influence of statins on procarboxypeptidase U (proCPU) biology and to search for possible effects and associations that can be followed up in a larger study.

METHODS

Blood was collected from 16 patients with hyperlipidemia, before and after 3 months of statin therapy (simvastatin 20 mg or atorvastatin 20 mg). Fifteen age-matched normolipemic persons served as control subjects. Lipid parameters and markers of inflammation and fibrinolysis (proCPU levels and clot lysis times) were determined in all samples.

FINDINGS

Mean (SD) proCPU levels were significantly higher in patients with hypercholesterolemia compared to control subjects (1186 [189] U/L vs 1061 [60] U/L). Treatment of these patients with a statin led to a significant average decrease of 11.6% in proCPU levels and brought the proCPU concentrations to the same level as in the control subjects. On a functional level, enhancement in plasma fibrinolytic potential was observed in the statin group, with the largest improvement in fibrinolysis seen in patients with the highest baseline proCPU levels and largest proCPU decrease upon statin treatment.

IMPLICATIONS

Increased proCPU levels are present in patients with hyperlipidemia. Statin treatment significantly decreased proCPU levels and improved plasma fibrinolysis in these patients. Moreover, our study indicates that patients with high baseline proCPU levels are most likely to benefit from statin therapy. The latter should be examined further in a large cohort.

Rosuvastatin use increases plasma fibrinolytic potential: a randomised clinical trial

We conducted a study to assess the effect of rosuvastatin use on fibrinolysis in patients with previous venous thromboembolism (VTE). This was a post hoc analysis within the STAtins Reduce Thrombophilia (START) study (NCT01613794). Plasma fibrinolytic potential, fibrinogen, plasmin inhibitor, plasminogen activator inhibitor‐1 (PAI‐1) and thrombin‐activatable fibrinolysis inhibitor (TAFI) were measured before and after four weeks of rosuvastatin or no treatment in participants with prior confirmed VTE, after ending anticoagulant therapy. In the non‐rosuvastatin group (n = 121), plasma fibrinolytic potential and individual fibrinolysis parameters did not change at the end of the study versus the baseline, whereas in the rosuvastatin group (n = 126), plasma fibrinolytic potential increased: the mean clot lysis time decreased by 8·75 min (95% CI −13·8 to −3·72), and plasmin inhibitor levels and TAFI activity were lower at the end of the study (−0·05 U/ml; 95% CI −0·07 to −0·02 and −4·77%; 95% CI −6·81 to −2·73, respectively). PAI‐1 levels did not change and fibrinogen levels were 0·17 g/l (95% CI 0·04–0·29) higher. In participants with prior VTE, rosuvastatin use led to an increased fibrinolytic potential compared with non‐statin use. Our findings support the need for further studies on the possible role for statins in the secondary prevention of VTE.

The effect of atorvastatin on haemostatic parameters in apparently healthy dogs

OBJECTIVE

To determine the effect of atorvastatin on haemostatic parameters as measured by prothrombin time, activated partial thromboplastin time and thromboelastography in apparently healthy dogs administered 2 mg/kg orally once daily for 1 week.

MATERIALS AND METHODS

Prospective study of 20 apparently healthy client-owned dogs at a small animal specialty hospital. Dogs had a baseline complete blood count, serum chemistry profile, fibrinogen, platelet count, prothrombin time, activated partial thromboplastin time and thromboelastography performed. Each dog was then administered approximately 2 mg/kg of atorvastatin orally once daily for 1 week, and the laboratory tests were repeated. Adverse effects attributed to atorvastatin were recorded.

RESULTS

All 20 enrolled dogs completed the study. Dogs received a median dose of 2.06 mg/kg (range 1.94 to 2.44 mg/kg) atorvastatin once daily, which was associated with a significant increase in pulse rate, mean corpuscular haemoglobin concentration, albumin and a significant decrease in mean corpuscular volume, cholesterol and lipase values compared with baseline. On thromboelastography, there was a significant increase in maximum amplitude, G, coagulation index, amplitude at 30 minutes, amplitude at 60 minutes and significant decrease in percentage of clot lysed at 30 minutes and percentage of clot lysed at 60 minutes values compared with baseline. Six dogs had a noticeable increase in appetite.

CLINICAL SIGNIFICANCE

The results of this study suggest that atorvastatin may produce a procoagulant effect in dogs, although the clinical significance is unclear. Polyphagia was the most commonly reported adverse effect.

The role of oral fluvastatin on postoperative peritoneal adhesion formation in an experimental rat model

BACKGROUND

Postoperative peritoneal adhesions are a momentousness complication after abdominal surgery. Although varied means have been used to prevent and treat adhesions, the effects have not been satisfactory. Fluvastatin, a HMG-CoA reductase inhibitors, exhibits a variety of pharmacological effects. Aim of this study was to evaluate the effect of fluvastatin on postoperative peritoneal adhesion formation.

METHODS

Seventy-five male Wistar rats weighting 220-250g were randomly assigned equally to three groups. Group A was given sham operation without treatment, Group B was the model group in which postoperative peritoneal adhesion model was created without medication, and Group C was given oral fluvastatin treatment after postoperative peritoneal adhesion model created. After laparotomy on day 7, macroscopic and pathological assessment were evaluated, IL-1β and t-PA in plasma were performed to measure, and tissue samples were taken to measure MMP-9 protein.

RESULTS

There were significant differences between the groups on adhesion grade (p < .05), IL-1β content of the plasma and t-PA activity of the adhesions (p < .05). The grading of adhesion demonstrated significant differences between all groups. The levels of the IL-1β content of plasma, t-PA activity and MMP-9 of adhesion showed pivotal changes in Group B compared with Group A and C, while the difference between Group A and C was not statistically significant.

CONCLUSION

Oral fluvastatin application could reduce formation of intra-abdominal adhesion by promoting expression of MMP-9 level, lowering the levels of IL-1β and increasing the activity of t-PA after abdominal surgery.

Impact of von Willebrand factor on coronary plaque burden in coronary artery disease patients treated with statins

High von Willebrand factor (VWF) levels have been reported to be associated with an increased risk of cardiovascular events. However, the relationship between VWF levels and coronary atherosclerosis in patients with coronary artery disease (CAD) who have already received stain treatment is still unclear. We examined the association between VWF levels and coronary plaque as assessed by intravascular ultrasound (IVUS) in CAD patients treated with statins. Ninety-one CAD patients who underwent percutaneous coronary intervention under IVUS guidance, and who were already receiving statin treatment based on Japanese guidelines, were included. An IVUS examination was performed for the culprit lesion, and plasma VWF antigen levels were measured using enzyme-linked immuno sorbent assay. In all of the patients, the low-density lipoprotein cholesterol levels just before the IVUS examination were low (86 ± 26 mg/dL). The VWF levels were positively correlated with the plaque burden expressed as percent atheroma volume (PAV) (r = 0.39, P = .001), while there was no significant association between VWF and plaque composition. Multivariate stepwise regression analysis showed that higher VWF levels were independently associated with increased PAV (β=0.26, P = .01). In CAD patients who had already been treated with statins, higher VWF levels were associated with a higher coronary plaque burden, suggesting that a high VWF level may be a marker of the residual cardiovascular risk after statin treatment.

Decrements in the Thrombin Activatable Fibrinolysis Inhibitor (TAFI) Levels in Association with Orlistat Treatment in Obesity

Obesity and its associated metabolic complications can impair the physiologic regulation of fibrinolysis, leading to a hyper coagulable state. We aimed to assess circulating thrombin activatable fibrinolysis inhibitor (TAFI) levels in obese female patients and to test the effects of orlistat-induced weight loss on basal TAFI concentrations. Obese female outpatients age 18 and older, with a body mass index (BMI, calculated as weight in kilograms divided by the square of height in meters) of at least 30, were included into the study. Thirteen nonobese (median BMI, 22.60 kg/m2) age-matched females were taken as controls. Plasma TAFI levels were measured before orlistat administration and after 6 months of orlistat treatment in the obese group and only one measurement was done in the control group. Twenty-seven obese patients were recruited into the study. The median TAFI level of the control group was 124.00; this value was significantly lower than the basal TAFI level of the obese group (p < 0.001). TAFI levels after orlistat therapy were statistically significantly lower than basal TAFI levels (p < 0.001) in the obese group. Hemostatic abnormalities including TAFI alterations represent a link between obesity and vascular thrombosis. Effective interventions should be considered in improving the obesity-associated prothrombotic risk profile.

Lipid-lowering efficacy of atorvastatin

BACKGROUND

This represents the first update of this review, which was published in 2012. Atorvastatin is one of the most widely prescribed drugs and the most widely prescribed statin in the world. It is therefore important to know the dose-related magnitude of effect of atorvastatin on blood lipids.

OBJECTIVES

Primary objective To quantify the effects of various doses of atorvastatin on serum total cholesterol, low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol and triglycerides in individuals with and without evidence of cardiovascular disease. The primary focus of this review was determination of the mean per cent change from baseline of LDL-cholesterol. Secondary objectives • To quantify the variability of effects of various doses of atorvastatin.• To quantify withdrawals due to adverse effects (WDAEs) in placebo-controlled randomised controlled trials (RCTs).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 11, 2013), MEDLINE (1966 to December Week 2 2013), EMBASE (1980 to December Week 2 2013), Web of Science (1899 to December Week 2 2013) and BIOSIS Previews (1969 to December Week 2 2013). We applied no language restrictions.

SELECTION CRITERIA

Randomised controlled and uncontrolled before-and-after trials evaluating the dose response of different fixed doses of atorvastatin on blood lipids over a duration of three to 12 weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility criteria for studies to be included and extracted data. We collected information on withdrawals due to adverse effects from placebo-controlled trials.

MAIN RESULTS

In this update, we found an additional 42 trials and added them to the original 254 studies. The update consists of 296 trials that evaluated dose-related efficacy of atorvastatin in 38,817 participants. Included are 242 before-and-after trials and 54 placebo-controlled RCTs. Log dose-response data from both trial designs revealed linear dose-related effects on blood total cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides. The Summary of findings table 1 documents the effect of atorvastatin on LDL-cholesterol over the dose range of 10 to 80 mg/d, which is the range for which this systematic review acquired the greatest quantity of data. Over this range, blood LDL-cholesterol is decreased by 37.1% to 51.7% (Summary of findings table 1). The slope of dose-related effects on cholesterol and LDL-cholesterol was similar for atorvastatin and rosuvastatin, but rosuvastatin is about three-fold more potent. Subgroup analyses suggested that the atorvastatin effect was greater in females than in males and was greater in non-familial than in familial hypercholesterolaemia. Risk of bias for the outcome of withdrawals due to adverse effects (WDAEs) was high, but the mostly unclear risk of bias was judged unlikely to affect lipid measurements. Withdrawals due to adverse effects were not statistically significantly different between atorvastatin and placebo groups in these short-term trials (risk ratio 0.98, 95% confidence interval 0.68 to 1.40).

AUTHORS' CONCLUSIONS

This update resulted in no change to the main conclusions of the review but significantly increases the strength of the evidence. Studies show that atorvastatin decreases blood total cholesterol and LDL-cholesterol in a linear dose-related manner over the commonly prescribed dose range. New findings include that atorvastatin is more than three-fold less potent than rosuvastatin, and that the cholesterol-lowering effects of atorvastatin are greater in females than in males and greater in non-familial than in familial hypercholesterolaemia. This review update does not provide a good estimate of the incidence of harms associated with atorvastatin because included trials were of short duration and adverse effects were not reported in 37% of placebo-controlled trials.

Evaluation of topical application and systemic administration of rosuvastatin in preventing epidural fibrosis in rats

BACKGROUND CONTEXT

Epidural fibrosis is a major challenge in spine surgery, with some patients having recurrent symptoms secondary to excessive formation of scar tissue resulting in neurologic compression. One of the most important factors initiating the epidural fibrosis is assumed to be the transforming growth factor-1β (TGF-1β). Rosuvastatin (ROS) has shown to demonstrate preventive effects over fibrosis via inhibiting the TGF-1β.

PURPOSE

We hypothesized that ROS might have preventive effects over epidural fibrosis through the inhibition of TGF-1β pathways.

STUDY DESIGN

Experimental animal study.

METHODS

Forty-eight adult male Wistar Albino rats were equally and randomly divided into four groups (laminectomy, spongostan, topical ROS, and systemic ROS). Laminectomy was performed at the L3 level in all rats. Four weeks later, the extent of epidural fibrosis was assessed both macroscopically and histopathologically.

RESULTS

Our data revealed that topical application and systemic administration of ROS both were effective in reducing epidural fibrosis formation. Furthermore, the systemic administration of ROS yielded better results than topical application.

CONCLUSIONS

Both topical application and systemic administration of ROS show meaningful preventive effects over epidural fibrosis through multiple mechanisms. The results of our study provide the first experimental evidence of the preventive effects of ROS over epidural fibrosis.

Human tissue-type plasminogen activator

Tissue-type plasminogen activator (t-PA ) plays an important role in the removal of intravascular fibrin deposits and has several physiological roles and pathological activities in the brain. Its production by many other cell types suggests that t-PA has additional functions outside the vascular and central nervous system. Activity of t-PA is regulated at the level of its gene transcription, its mRNA stability and translation, its storage and regulated release, its interaction with cofactors that enhance its activity, its inhibition by inhibitors such as plasminogen activator inhibitor type 1 or neuroserpin, and its removal by clearance receptors. Gene transcription of t-PA is modulated by a large number of hormones, growth factors, cytokines or drugs and t-PA gene responses may be tissue-specific. The aim of this review is to summarise current knowledge on t-PA function and regulation of its pericellular activity, with an emphasis on regulation of its gene expression.

Can statins prevent pregnancy complications?

Statins are potent inhibitors of cholesterol biosynthesis. The beneficial effects of the statins in preventing cardiovascular diseases are not entirely due to cholesterol reduction. Numerous studies suggest that the benefits observed with statins may be mediated by pleiotropic effects that are cholesterol-independent. There is now compelling evidence that statin therapy may diminish inflammation and oxidative stress, increase angiogenesis, inhibit the coagulation cascade and protect the endothelium. Several animal studies demonstrated that statins prevent pregnancy complications such as recurrent miscarriages and preeclampsia. Epidemiological data collected to date suggest that statins are not major teratogens. Clinical trials should be performed to demonstrate the effectiveness of statins in preventing bad pregnancy outcomes in women. Some of these trials recently started. This article summarizes the numerous effects of statins that can contribute to the pregnancy protection observed in animal models.

Lipid lowering efficacy of atorvastatin

BACKGROUND

Atorvastatin is one of the most widely prescribed drugs and the most widely prescribed statin in the world. It is therefore important to know the dose-related magnitude of effect of atorvastatin on blood lipids.

OBJECTIVES

To quantify the dose-related effects of atorvastatin on blood lipids and withdrawals due to adverse effects (WDAE).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library Issue 4, 2011, MEDLINE (1966 to November 2011), EMBASE (1980 to November 2011), ISI Web of Science (1899 to November 2011) and BIOSIS Previews (1969 to November 2011). No language restrictions were applied.

SELECTION CRITERIA

Randomised controlled and uncontrolled before-and-after trials evaluating the dose response of different fixed doses of atorvastatin on blood lipids over a duration of 3 to 12 weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. WDAE information was collected from the placebo-controlled trials.

MAIN RESULTS

Two hundred fifty-four trials evaluated the dose-related efficacy of atorvastatin in 33,505 participants. Log dose-response data revealed linear dose-related effects on blood total cholesterol, low-density lipoprotein (LDL)-cholesterol and triglycerides. Combining all the trials using the generic inverse variance fixed-effect model for doses of 10 to 80 mg/day resulted in decreases of 36% to 53% for LDL-cholesterol. There was no significant dose-related effects of atorvastatin on blood high-density lipoprotein (HDL)-cholesterol. WDAE were not statistically different between atorvastatin and placebo for these short-term trials (risk ratio 0.99; 95% confidence interval 0.68 to 1.45).

AUTHORS' CONCLUSIONS

Blood total cholesterol, LDL-cholesterol and triglyceride lowering effect of atorvastatin was dependent on dose. Log dose-response data was linear over the commonly prescribed dose range. Manufacturer-recommended atorvastatin doses of 10 to 80 mg/day resulted in 36% to 53% decreases of LDL-cholesterol. The review did not provide a good estimate of the incidence of harms associated with atorvastatin because of the short duration of the trials and the lack of reporting of adverse effects in 37% of the placebo-controlled trials.

Postoperative adhesion prevention using a statin-containing cellulose film in an experimental model

BACKGROUND

Intraperitoneal adhesions are a common problem in abdominal surgery. The aim of this study was to compare the effectiveness of Statofilm, a novel antiadhesive film based on cross-linked carboxymethylcellulose and atorvastatin, with that of sodium hyaluronate-carboxymethylcellulose (Seprafilm(®)) in the prevention of postoperative intraperitoneal adhesions in rats.

METHODS

One hundred male Wistar rats underwent a laparotomy and adhesions were induced by caecal abrasion. The animals were allocated to five groups: a control group with no adhesion barrier, Seprafilm(®) group, placebo group with a film containing carboxymethylcellulose without atorvastatin, and low- and high-dose groups with films containing carboxymethylcellulose and atorvastatin 0·125 and 1 mg per kg bodyweight respectively. Adhesions were classified by two independent surgeons 2 weeks after surgery. Caecal biopsies were obtained for histological evaluation of fibrosis, inflammation and vascular proliferation.

RESULTS

All antiadhesive film groups (Seprafilm(®), placebo, low-dose and high-dose) had statistically significant adhesion reduction compared with the control group (P < 0·001, P = 0·015, P < 0·001 and P < 0·001 respectively). The low-dose Statofilm was superior to Seprafilm(®) in terms of adhesion prevention (P = 0·001). Adhesions were present in three-quarters of rats in the Seprafilm(®) group, but only one-quarter in the low-dose Statofilm group.

CONCLUSION

The data suggest that the newly developed adhesion barrier Statofilm has better results than Seprafilm(®) in preventing postoperative adhesions in rats. A low-dose atorvastatin-containing film, such as Statofilm, could be evaluated for future clinical application.

Clot lysis time in platelet-rich plasma: method assessment, comparison with assays in platelet-free and platelet-poor plasmas, and response to tranexamic acid

Fibrinolysis dysfunctions cause bleeding or predisposition to thrombosis. Platelets contain several factors of the fibrinolytic system, which could up or down regulate this process. However, the temporal relationship and relative contributions of plasma and platelet components in clot lysis are mostly unknown. We developed a clot lysis time (CLT) assay in platelet-rich plasma (PRP-CLT, with and without stimulation) and compared it to a similar one in platelet-free plasma (PFP) and to another previously reported test in platelet-poor plasma (PPP). We also studied the differential effects of a single dose of tranexamic acid (TXA) on these tests in healthy subjects. PFP- and PPP-CLT were significantly shorter than PRP-CLT, and the three assays were highly correlated (p < 0.0001). PFP- and PPP-, but more significantly PRP-CLT, were positively correlated with age and plasma PAI-1, von Willebrand factor, fibrinogen, LDL-cholesterol, and triglycerides (p < 0.001). All these CLT assays had no significant correlations with platelet aggregation/secretion, platelet counts, and pro-coagulant tests to explore factor X activation by platelets, PRP clotting time, and thrombin generation in PRP. Among all the studied variables, PFP-CLT was independently associated with plasma PAI-1, LDL-cholesterol, and triglycerides and, additionally, stimulated PRP-CLT was also independently associated with plasma fibrinogen. A single 1 g dose of TXA strikingly prolonged all three CLTs, but in contrast to the results without the drug, the lysis times were substantially shorter in non-stimulated or stimulated PRP than in PFP and PPP. This standardized PRP-CLT may become a useful tool to study the role of platelets in clot resistance and lysis. Our results suggest that initially, the platelets enmeshed in the clot slow down the fibrinolysis process. However, the increased clot resistance to lysis induced by TXA is overcome earlier in platelet-rich clots than in PFP or PPP clots. This is likely explained by the display of platelet pro-fibrinolytic effects. Focused research is needed to disclose the mechanisms for the relationship between CLT and plasma cholesterol and its potential pathophysiologic and clinical relevance.

Preventing intraperitoneal adhesions with atorvastatin and sodium hyaluronate/carboxymethylcellulose: a comparative study in rats

OBJECTIVES

The aim of this study was to compare the effectiveness of atorvastatin with the sodium hyaluronate/carboxymethylcellulose (HA/CMC, Seprafilm; Genzyme; Genzyme Biosurgery Corporation, Cambridge, MA) in preventing postoperative intraperitoneal adhesion formation in rats.

METHODS

Sixty Wistar rats underwent a laparotomy, and adhesions A were induced by cecal abrasion. The animals were divided into 4 groups: group 1, control A; group 2, (A + atorvastatin); group 3, (A + HA/CMC), and group 4, (A + atorvastatin + HA/CMC). The atorvastatin (groups 2 and 4) and HA/CMC (groups 3 and 4) were administered intraperitoneally before the abdominal wall was closed. After 14 days, adhesions were classified by 2 independent surgeons.

RESULTS

The adhesion scores (mean +/- standard deviation) for groups 1, 2, 3, and 4 were 2.93 +/- .59, 1.85 +/- 1.07, 1.80 +/- .86, and 1.93 +/- .70, respectively. The differences in adhesion scores among all 3 preventive groups (groups 2, 3, and 4) were statistically significant when compared with the control group (P = .005, P = .002, and P = .009, respectively).

CONCLUSIONS

These data suggest that atorvastatin, administered intraperitoneally, is as effective as HA/CMC without an expectable additive effect in preventing postoperative adhesions in rats.

Early effects of low versus high dose atorvastatin treatment on coagulation and inflammation parameters in patients with acute coronary syndromes

AIM

To demonstrate the efficacy of low or high dose statin treatment on C-reactive protein (CRP), von Willebrand Factor (vWF) and Factor VII (FVII) during the first two weeks of acute coronary syndromes.

PATIENTS AND METHODS

Patients with acute coronary syndromes (n=60) were randomly and prospectively allocated in three different groups. They received 10 mg (low dose), 80 mg (high dose) of atorvastatin and placebo for two weeks. Plasma levels of CRP, vWF and FVII were compared at baseline, first and second weeks of treatment.

RESULTS

Low dose therapy resulted in non-significant elevation of CRP at first week, although high dose therapy significantly lowered its level (7.75+/-3.57 vs 7.13+/-2.95; p=.04). Both low and high dose therapies effectively suppressed the production and elevation of vWF in contrast to placebo (121.15+/-31.99 vs 139.7+/-28.53; p=.04).

CONCLUSIONS

High dose atorvastatin significantly decreased CRP during the early days of acute coronary syndromes. Although vWF significantly increased in placebo group, both low and high dose atorvastatin treatments effectively suppressed its increased production.

Atorvastatin induces associated reductions in platelet P-selectin, oxidized low-density lipoprotein, and interleukin-6 in patients with coronary artery diseases

The development and progression of atherosclerosis comprises various processes, such as endothelial dysfunction, chronic inflammation, thrombus formation, and lipid profile modification. Statins are 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors that have pleiotropic effects in addition to cholesterol-lowering properties. However, the mechanisms of these effects are not completely understood. Here, we investigated whether atorvastatin affects the levels of malondialdehyde-modified low-density lipoprotein (MDALDL), an oxidized LDL, the proinflammatory cytokine interleukin-6 (IL-6), or platelet P-selectin, a marker of platelet activation, relative to that of LDL cholesterol (LDL-C). Forty-eight patients with coronary artery disease and hyperlipidemia were separated into two groups that were administered with (atorvastatin group) or without (control group) atorvastatin. The baseline MDA-LDL level in all participants significantly correlated with LDL-C (r = 0.71, P < 0.01) and apolipoprotein B levels (r = 0.66, P < 0.01). Atorvastatin (10 mg/day) significantly reduced the LDL-C level within 4 weeks and persisted for a further 8 weeks of administration. Atorvastatin also reduced the MDA-LDL level within 4 weeks and further reduced it over the next 8 weeks. Platelet P-selectin expression did not change until 4 weeks of administration and then significantly decreased at 12 weeks, whereas the IL-6 level was gradually, but not significantly, reduced at 12 weeks. In contrast, none of these parameters significantly changed in the control group within these time frames. The reduction (%) in IL-6 between 4 and 12 weeks after atorvastatin administration significantly correlated with that of MDALDL and of platelet P-selectin (r = 0.65, P < 0.05 and r = 0.70, P < 0.05, respectively). These results suggested that the positive effects of atorvastatin on the LDL-C oxidation, platelet activation and inflammation that are involved in atherosclerotic processes are exerted in concert after lowering LDL-C.

Statins (HMG-CoA reductase inhibitors) decrease postoperative adhesions by increasing peritoneal fibrinolytic activity

OBJECTIVES

The aims of this study were to determine if statins reduce adhesion formation in vivo and to identify the mechanism of action in vitro.

BACKGROUND

: Intraperitoneal adhesions develop in up to 95% of patients following laparotomy. Adhesions are reduced by mechanisms that up-regulate fibrinolysis within the peritoneum. Statins promote fibrinolysis in the cardiovascular system and may play a role in the prevention of adhesions.

METHODS

Adhesions were induced in rats (n = 102) using our previously described ischemic button model. Rats received vehicle (controls), lovastatin (30 mg/kg), or atorvastatin (30 mg/kg) as a single intraperitoneal dose at the time of laparotomy. Animals were killed and adhesions were quantified at day 7. Peritoneal fluid and tissue were collected at day 1 to measure tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) by real-time PCR and ELISA. To assess the effects of statins on wound healing, burst pressures were measured in anastomoses of the colon. The effects of lovastatin on tPA and PAI-1 production were measured in vitro in human mesothelial cells (HMC) in the presence or absence of mevalonate (MVA), geranylgeranyl-pyrophosphate (GGPP) and farnesyl-pyrophosphate (FPP), all intermediates in the cholesterol pathway downstream of HMG-CoA. The effect of a Rho protein inhibitor, exoenzyme C3 transferase, on tPA production was also determined.

RESULTS

Lovastatin and atorvastatin reduced adhesion formation by 26% and 58%, respectively (P < 0.05), without affecting anastomotic burst pressure. At 24 hours, tPA mRNA levels in peritoneal tissue and tPA activity in peritoneal fluid from lovastatin-treated animals were increased by 57% and 379%, respectively (P < 0.05), while PAI-1 levels were unchanged. HMC incubated with either lovastatin or atorvastatin showed concentration-dependent increases in tPA production and decreases in PAI-1 production (P < 0.05). These lovastatin-induced changes in tPA and PAI-1 production were significantly reversed by the addition of MVA, GGPP, and FPP. The Rho protein inhibitor increased tPA production and rescued tPA production from the inhibitory effect of GGPP.

CONCLUSION

These data suggest that statins administered within the peritoneum can up-regulate local fibrinolysis, while the in vitro studies show that this effect may be mediated, in part, by intermediates of the cholesterol biosynthetic pathway that regulate Rho protein signaling.

Elevated thrombin activatable fibrinolysis inhibitor (TAFI) antigen levels in overt and subclinical hypothyroid patients were reduced by levothyroxine replacement

The influence of hypothyroidism on haemostasis is an active research area. Not only bleeding tendency but also hypercoagulable states have been reported in hypothyroid patients. Decreased and increased fibrinolytic activity in hypothyroid patients has been shown in several studies. Thrombin activatable fibrinolysis inhibitor (TAFI) is an inhibitor of fibrinolysis, which has been recently isolated from human plasma. The aim of our study was to determine plasma TAFI antigen levels in overt and subclinical hypothyroidism, and to investigate the effect of levothyroxine treatment on TAFI levels. The study was performed in age- and sex-matched 30 overt hypothyroid, 30 subclinical hypothyroid patients, and 30 healthy controls. Blood samples were obtained from patients with overt and subclinical hypothyroidism before levothyroxine replacement, and one month after achieving a euthyroid state with levothyroxine. TAFI antigen levels were measured using Enzyme-Linked ImmunoSorbent Assay kits (Affinity Biologicals; Ontario, Canada). In baseline evaluation both the overt and subclinical hypothyroid groups had higher TAFI antigen levels than control group (p<0.05). High levels of TAFI antigen were correlated with the degree of thyroid failure. After achieving euthyroid state with levothyroxine replacement, TAFI antigen levels decreased significantly in patients with overt and subclinical hypothyroidism (p<0.05). Our data suggest that there are elevated plasma levels of TAFI antigen both in overt and subclinical hypothyroidism, which may be associated with hypofibrinolysis and elevated risk of thrombosis. Normalization of thyroid state by levothyroxine replacement seems to be effective in lowering of TAFI antigen levels in hypothyroidism.

Effects of early administration of atorvastatin treatment on thrombotic process in normocholesterolemic patients with unstable angina

BACKGROUND

Although statin-treatment during the acute phase of unstable coronary syndromes improve the outcome their effects on thrombosis/fibrinolysis system in normocholesterolemic patients admitted with unstable angina remain obscure. We assessed the effects of short-term atorvastatin treatment on thrombotic/fibrinolysis markers in normocholesterolemic in patients with unstable angina.

METHODS

Forty-five patients with unstable angina were allocated into two groups to receive atorvastatin 10 mg/day (n = 24) or no statin (n = 21) for 6 weeks. Circulating levels of von Willebrand Factor (vWF), factor V (fV), protein C (prC), tissue plasminogen activator (tPA) and antithrombin III (ATIII) were measured by enzyme linked immunosorbent assay, by the patients admission and at the 1st and 6th week of the study.

RESULTS

After 1 week of treatment, a significant increase of ATIII (p < 0.05), fV (p < 0.01) and vWF (p < 0.05) was found in the control group, but not in atorvastatin-treated group. Similarly, at 6 weeks after admission, plasma levels of ATIII were still significantly higher than at baseline in controls (p < 0.05), but not in atorvastatin-treated group. Plasma levels of PrtC were significantly increased in both controls (p < 0.01) and atorvastatin-treated patients (p < 0.05) at 1 week, while remained unaffected in atorvastatin-treated group at 6th week. There was no significant difference in the variations of plasma levels of tPA, PrtS and fVII between the two groups at 1 and 6 weeks after admission.

CONCLUSIONS

In normocholesterolemic patients admitted with unstable angina the early administration of atorvastatin, significantly affects von Willebrand factor levels and the expression of liver-derived components of both thrombosis and fibrinolysis system.

Atorvastatin

The introduction of statins has drastically changed the treatment and prevention of atherosclerotic vascular disease. By lowering lipid levels and reducing the risk of coronary heart disease, these drugs are among the most effective at reducing morbidity and mortality available to clinical practice. In fact, these compounds have demonstrated the reversible nature of the process of atherosclerosis and can be considered the most useful drugs we currently have in our armamentarium in the prevention of atherosclerosis and its clinical sequelae. Atorvastatin provides pronounced lipid lowering in a broad range of individuals with hypercholesterolaemia and, as such, is an appropriate first-line therapy for patients at low to high risk of coronary heart disease. Reductions in total and low-density lipoprotein cholesterol achieved with atorvastatin have been shown to translate into reductions in risk of cardiovascular morbidity and mortality in both primary and secondary prevention settings. Significant clinical benefits have specifically been observed among patients with Type 2 diabetes and in those with acute coronary syndromes. In common with other members of the statin class, atorvastatin is well tolerated, and adverse events are generally mild and transient in nature. Despite the significant clinical benefits provided by atorvastatin, its full potential in the management of atherosclerotic disease has yet to be wholly explored; however, studies currently ongoing will answer many of the outstanding questions.

Hypolipidemic Drugs Affect Monocyte IL-1β Gene Expression and Release in Patients with IIa and IIb Dyslipidemia

Because atherosclerosis has been proven to be an inflammatory disease, it became obvious that the proper treatment of dyslipidemic patients should not only correct lipid parameters but also inhibit the inflammatory state. One of the crucial proinflammatory and procoagulant cytokines participating in the pathogenesis of atherosclerosis is interleukin-1beta (IL-1beta). Therefore, the aim of the study was to asses the effect of statin and fibrate therapy (for dyslipidemia IIa and IIb, respectively) on IL-1beta gene expression and monocyte release evaluated in each patient. Additionally, the effect of hypolipidemic therapy on fibrinolysis was evaluated. The study was carried out in 37 patients: 12 with biochemically confirmed type IIa dyslipidemia (treated with atorvastatin), 12 with type IIb dyslipidemia (treated with fenofibrate), and 13 age- and sex-matched normolipidemic persons (control). IL-1beta concentrations in cultured monocytes and PAI-1 (Plasminogen Activator Inhibitor) plasma levels were measured using the ELISA method. To evaluate the expression of IL-1beta gene in monocytes, a semiquantitive RT-PCR procedure was performed. The results were normalized with the expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a housekeeping gene. Although IL-1beta monocyte release was markedly elevated in patients with atherogenic dyslipidemias, IL-1beta gene expression was only slightly and nonsignificantly higher in the studied groups versus control. We have observed significant reduction of IL-1beta mRNA expression after 30-day treatment with the examined drugs (atorvastatin, 2.10 +/- 0.50 versus 1.05 +/- 0.15; P < 0.001, fenofibrate; 2.27 +/- 0.48 versus 1.23 +/- 0.27; P < 0.01). There was no significant difference between statin and fibrate effect on IL-1beta mRNA expression. Similarly, we have noticed significant reduction of IL-1beta release by cultured monocytes after 30-day statin therapy (133.0 +/- 5.7 pg/mL versus 77.0 +/- 3.6 pg/mL; P < 0.01) and fibrate therapy (143.9 +/- 6.5 pg/mL versus 86.2 +/- 5.9 pg/mL; P < 0.01). Besides this antiinflammatory effect, we have observed a 30% reduction of PAI-1 plasma levels in both treated groups. In conclusion, effective 1-month hypolipidemic therapy with atorvastatin or fenofibrate diminished plasma levels of proinflammatory and procoagulatory state markers.