PPARγ, NF-κB and the UPR pathway as new molecular targets in the anti-inflammatory actions of NSAIDs: Novel applications in cancers and central nervous system diseases?

Non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin, diclofenac, ibuprofen, or celecoxib have a well-established and unquestionable role in the human therapeutic arsenal, but still new perspectives are being discovered. This review presents new anti-inflammatory mechanisms of NSAIDs action, other than the classical one, i.e., the inhibition of cyclooxygenase (COX) isoforms leading to the prostanoids synthesis blockage. Literature data show that this group of drugs can activate anti-inflammatory peroxisome proliferator-activated receptor gamma (PPARγ), inhibit pro-inflammatory nuclear factor-κB (NF-κB) activation or modulate the components of the unfolded protein response (UPR) pathway. These alternative pathways induced by NSAIDs may not only enhance their basic anti-inflammatory mechanism of action but also promote other effects of the drugs such as anti-cancer. It was also proved that neuroinflammation, with the involvement of NF-κB, PPARγ and the components of the UPR pathway has an essential impact on the development of central nervous system (CNS) diseases. Thus, it seems possible that these new molecular targets may expand the use of NSAIDs, e.g., in the treatment of cancers and/or CNS disorders.

Antagonists of Vitamin K-Popular Coumarin Drugs and New Synthetic and Natural Coumarin Derivatives.

Many natural coumarins and their chemically synthesized analogs and derivatives exert diverse properties, such as anticancer, antioxidant, anti-inflammatory, or anticoagulant, with the latter being of the utmost importance. The widely used warfarin, acenocoumarol, and phenprocoumon exert anticoagulant properties by inhibiting the vitamin K epoxide reductase complex. In this interdisciplinary review, we present biochemical principles of the coagulation processes and possible methods for their tuning based on the use of coumarins. We also summarize chemical methods of synthesis of coumarins and discuss structures and properties of those that have been used for a long time, as well as newly synthesized compounds. Brief information on the clinical use of coumarins and other anticoagulant drugs is given, including the severe effects of overdosing and methods for reversing their action.

Analysis of genetic polymorphisms of glutathione S-transferase (GSTP1, GSTM1, and GSTT1) in Polish patients with systemic sclerosis.

AIM: It is commonly assumed that a genetically determined polymorphism of xenobiotic biotransformation plays a particular role in the development of such disease entities in which chemical compounds and environmental pollutants are relevant etiologic factors. Systemic sclerosis (SSc, scleroderma) belongs to diseases of connective tissue, characterized by chronic inflammation developing on an autoimmune background. The current state of knowledge on the etiopathogenesis of autoimmune diseases indicates the existence of many factors affecting the development of the disease, including factors of the external environment. Considering all the above, a study on a role of genetic polymorphisms of glutathione S-transferase has been undertaken in which predisposition to SSc in a Polish population was assessed. METHODS: The study was carried out in 161 subjects: 61 patients with SSc and 100 healthy volunteers. A determination of the polymorphism of GSTM1 and GSTT1 was performed with a multiplex PCR (polymerase chain reaction). The GSTP1 polymorphism was determined by using the PCR restriction fragment length polymorphism. RESULTS: The risk of developing SSc was 3-fold higher for persons with the null GSTM1 and GSTT1 genotypes (odds ratio [OR] = 3.3; P = .0051). The risk for SSc was also demonstrated to be over 2.5-fold greater in the GSTP1 Ile/Val genotype individuals (OR = 2.62; P = .0037). Carriers of the GSTP1 Val variant allele had a greater than 2-fold increase in SSc risk (OR = 2.41; P = .0006). CONCLUSION: The genetic polymorphism of glutathione S-transferase may affect the risk of SSc in a Polish population.

Haplotypes of ABCB1 1236C >T (rs1128503), 2677G >T/A (rs2032582), and 3435C >T (rs1045642) in patients with bullous pemphigoid.

Bullous pemphigoid (BP) constitutes the most prevalent disease in the group of bullous dermatoses with the autoimmune background. Some authors suggest that certain cytokines (IL-2, IFN-γ) may be transported by P-glycoprotein (P-gp), the product of the ABCB1 gene. ABCB1 polymorphism might affect not only the effectiveness of treatment with drugs that are P-gp substrates but also contribute to the development of diseases, including BP. In the present work, we resolved to conduct a haplotype analysis of ABCB1 in patients with BP and to answer the question of whether any of the haplotypes are able to affect the incidence of this entity. The study involved 71 patients with BP and 100 healthy volunteers. Determination of polymorphisms 1236C > T and 3435C > T in ABCB1 was carried out with the PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphism) method. The 2677G > T/A ABCB1 polymorphism was analyzed with the allele-specific PCR method. It was observed that the 1236T-2677G-3435T haplotype occurred with a statistically significantly lower frequency in patients with BP than in controls (1.4 vs. 10.0%). Carriers of this haplotype were also shown to have had a low relative risk for BP (OR = 0.13, p = 0.003). Haplotype analysis of ABCB1 conducted in patients with BP demonstrated that the 1236T-2677G-3435T haplotype may protect against development of this entity.

Assessment of release factors of b-type natriuretic peptide during the exercise test in patients with diabetes and after myocardial infarction with preserved left ventricular systolic function.

INTRODUCTION: The increased concentration of B-type natriuretic peptide (BNP) is an expression of overload of the heart, regardless of the cause. Exercise test is a helpful method of assessing the exercise tolerance and myocardial ischemia. THE AIM: The aim of the study is to determine the factors that cause the release of BNP during the exercise test. MATERIAL AND METHODS: The study included 99 patients with diabetes and after myocardial infarction with preserved left ventricular ejection fraction (EF≥40%). Before performing the exercise test (ExT) echocardiography was performed and blood sample was taken to determine BNP. Immediately after the exercise test another blood sample was taken to determine BNP. RESULTS: In 22 patients (22%) an increase in BNP ≥35pg/ml after the exercise test was observed. In patients with EF.

ABCB1-Gen-Polymorphismus in einer polnischen Kohorte ist mit Risiko für bullöses Pemphigoid assoziiert.

HINTERGRUND UND ZIELE: Polymorphismen im ABCB1-Gen, das für das P-Glykoprotein kodiert, können die intrazelluläre Konzentration von Xenobiotika beeinflussen und so zur Entwicklung von Autoimmunerkrankungen, einschließlich des bullösen Pemphigoids (BP), beitragen. In der vorliegenden Studie sollte untersucht werden, ob in einer polnischen Kohorte die C3435T- und G2677T/A-Polymorphismen im ABCB1-Gen mit dem Risiko für ein BP assoziiert sind. PATIENTEN UND METHODIK: Die Studie umfasste 71 Patienten mit BP und 156 gesunde Probanden. Der C3435T-Polymorphismus wurde mittels PCR-RFLP bestimmt und der G2677T/A-Polymorphismus mittels Allel-spezifischer PCR. ERGEBNISSE: Es gab zwar keine Korrelation zwischen dem C3435-Polymorphismus und dem BP-Risiko, aber wir konnten eine derartige Assoziation hinsichtlich des G2677T/A-Polymorphismus nachweisen. Das relative Risiko eines BP war bei Personen mit dem 2677TA-Genotyp um mehr als den Faktor fünf erhöht (OR = 5,52; p = 0,0063) und bei Trägern des 2677TT-Genotyps mehr als verdoppelt (OR = 2,40; p = 0,0076). Mit 2,40 (p = 0,000018) war die OR bei Trägern des 2677T-Allels ebenfalls erhöht. Die höhere Prävalenz des 2677GG-Genotyps und des 2677G-Allels bei der Kontrollgruppe sowie eine OR < 1,0 (0,22 beziehungsweise 0,33) legen eine Schutzfunktion des 2677G-Allels hinsichtlich der Ausbildung eines BP nahe. SCHLUSSFOLGERUNGEN: Die Ergebnisse der vorliegenden Studie zeigen, dass der G2677T/A-Polymorphismus im ABCB1-Gen das Risiko für die Entstehung eines BP beeinflussen könnte.

Genotype and haplotype analysis of ABCB1 at 1236, 2677 and 3435 among systemic sclerosis patients.

Systemic sclerosis (SSc) belongs to the group of systemic diseases of the connective tissue, which are characterized by a chronic autoimmune inflammatory process. P-glycoprotein, initially associated with the drug resistance in patients with cancer, becomes more and more often a subject of considerations in terms of its significance in the development of illnesses, including autoimmune diseases. The aim of the study was an attempt to answer the question whether there was a relationship between ABCB1 polymorphisms and morbidity of systemic sclerosis in a Polish population. The study was carried out in 61 patients with SSc and 100 healthy volunteers. Determination of polymorphisms C1236T and C3435T in ABCB1 was carried out with the PCR-RFLP (polymerase chain reaction - restriction fragment length polymorphism) method. The G2677T/A ABCB1 polymorphism was analysed with the allele-specific PCR method. No statistically significant differences were observed in the frequencies of ABCB1 genotypes and alleles between SSc patients and the control group. It was observed that haplotype 1236 C-2677 G-3435 T occurred in the group of patients with SSc statistically more frequently than in the group of healthy volunteers (25% vs. 15%; p = .032). Carriers of the haplotype demonstrated almost a twofold greater risk of SSc (OR = 1.85; p = .032). No statistically significant correlations for the other nine haplotypes were found. Presented results concerning the relationship of ABCB1 polymorphisms with susceptibility to systemic sclerosis are the first ones that were obtained in a Polish population. They imply that single nucleotide polymorphisms do not affect the risk for SSc, but the 1236 C-2677 G-3435 T haplotype might increase this risk.

ABCB1 gene is associated with the risk of bullous pemphigoid in a polish population.

BACKGROUND AND OBJECTIVES: Polymorphisms in the P-glycoprotein-encoding ABCB1 gene may affect the intracellular concentration of xenobiotics, and thus contribute to the development of autoimmune diseases, including bullous pemphigoid (BP). The objective of the present study was to investigate whether there is an association between the C3435T and G2677T/A polymorphisms in the ABCB1 gene and the risk of BP in a Polish population. PATIENTS AND METHODS: The study included 71 patients with BP and 156 healthy volunteers. Determination of the C3435T polymorphism was carried out using PCR-RFLP; the G2677T/A polymorphism, using allele-specific PCR. RESULTS: While there was no correlation between the C3435T polymorphism and the risk of BP, we did find such an association with respect to the G2677T/A polymorphism. The relative risk of BP was more than five times greater in individuals with the 2677TA genotype (OR = 5.52, p = 0.0063), and more than twice as high in carriers of the 2677TT genotype (OR = 2.40, p = 0.0076). At 2.40 (0.000018), the OR in carriers of the 2677T allele was also increased. The greater prevalence of the 2677GG genotype and the 2677G allele in the control group, as well as the OR < 1.0 (0.22 and 0.33, respectively), suggest a protective role of the 2677G allele with respect to the development of BP. CONCLUSIONS: The results of the present study indicate that the G2677T/A polymorphism in the ABCB1 gene may affect the risk of developing BP.

Rosuvastatin intensifies the beneficial effects of rho-kinase inhibitor in reversal of monocrotaline-induced pulmonary hypertension.

INTRODUCTION: It remains controversial whether statins have a beneficial effect on pulmonary arterial hypertension (PAH). This study is intended to evaluate whether statin, co-administered with Rho-kinase inhibitor, could enhance its efficacy. Although Rho-kinase inhibitors, including fasudil, have been reported to improve pulmonary hypertension in experimental and clinical studies, the combination of these agents has not been tested in the treatment of pulmonary hypertension (PH). MATERIAL AND METHODS: The effects of such a regimen on hemodynamics, right ventricle hypertrophy, and Rho-associated protein kinase (ROCK) activity in experimental monocrotaline (MCT)-induced pulmonary hypertension were examined. Fourteen days after monocrotaline injection (60 mg/kg), male rats were treated orally for another 14 days with fasudil (15 mg/kg per day), or with a combination of fasudil + rosuvastatin (10 mg/kg per day). RESULTS: The drug combination reversed the MCT-induced increase in right ventricle pressure (RVP) and reduced right ventricular hypertrophy (RV/LV + S ratio) more than Rho kinase inhibitor alone. The simultaneous administration of fasudil and rosuvastatin caused a further decrease of RhoA kinase activity in isolated lung tissues as compared to fasudil alone. CONCLUSIONS: The results indicate that rosuvastatin intensifies the beneficial effects of Rho-kinase inhibitor on the Rho/Rho-kinase pathway and such a combination may represent an option for the treatment of pulmonary arterial hypertension.

THE EFFECT OF IBUPROFEN ON bFGF, VEGF SECRETION AND CELL PROLIFERATION IN THE PRESENCE OF LPS IN HMEC-1 CELLS.

Ibuprofen belongs to the group of non-selective cyclooxygenase (COX) inhibitors, also known as traditional non-steroidal anti-inflammatory drugs (NSAIDs). Bacterial lipopolysaccharide, an inflammatory mimicking agent, is responsible for the production of prostaglandins and growth factors (VEGF and bFGF), and as inflammation and angiogenesis are closely associated with osteoarthritis, these factors play a functional role in the cardiovascular system. Therefore, the main aim of our study was to examine the effect of ibuprofen on cell viability and proliferation of HMEC-1 cells and VEGF and bFGF secretion under the inflammatory conditions. The effect of NSAID and LPS on bFGF and VEGF was analyzed by ELISA. Cell viability was measured by the MTT method and the proliferation by the [3H-thymidine test. LPS at 100 µg/mL stimulated the secretion of VEGF and bFGF by HMEC-1 cells. Ibuprofen at concentrations of 0.1 and 1 mM intensified the secretion of LPS-induced VEGF in a statistically significant manner (p < 0.05). Both concentrations of ibuprofen inhibited LPS-stimulated bFGF secretion (p < 0.05) in HMEC-1 in a concentration-dependent manner. The non-selective COX inhibitor decreased proliferation and cell viability induced by LPS in a concentration-dependent manner. The observed effects of ibuprofen on endothelial cells may further explain its effects as well as other NSAIDs on the cardiovascular system function in cardiovascular diseases.

The effect of hypoxia on PGE2-stimulated cAMP generation in HMEC-1.

Prostaglandin E2 (PGE2) is generated in various cells, including endothelial cells, and is responsible for various functions, such as vascular relaxation and angiogenesis. Effects of PGE2 are mediated via receptors EP1-EP4, among which EP2 and EP4 are coupled to Gs protein which activates adenylate cyclase (AC) and cAMP synthesis. The aim of this work was to study the ability of human microvascular endothelial cells (HMEC-1) to synthesize cAMP in the presence of PGE2, and to determine the effect of hypoxia on the PGE2- stimulated cAMP level. It was decided to evaluate the effect of PGE2 on the secretion of VEGF, an inducer of angiogenesis. In summary, our findings show that PGE2 induces cAMP production, but hypoxia may impair PGE2-stimulated activity of the AC-cAMP signaling pathway. These results suggest that the cardioprotective effect of PGE2/EP4/cAMP may be attenuated during ischemia. Furthermore, this study indicates that the pro-angiogenic effect of PGE2 is not associated with VEGF secretion in HMEC-1 cells.

HMG-COA reductase inhibitors: An opportunity for the improvement of imatinib safety. An experimental study in rat pulmonary hypertension.

BACKGROUND: Co-administration of statin with imatinib is thought to result in greater improvement in pulmonary arterial hypertension (PAH) than imatinib treatment alone, and hence may allow greater effectiveness of imatinib therapy at lower doses. METHODS: The effects of imanitib at dose of 20 and 50mg/kg bw given together with rosuvastatin or simvastatin were investigated with respect to right ventricle pressure (RVP), arterial blood pressure and right ventricle hypertrophy (RVH) in experimental monocrotaline (MCT)-induced pulmonary hypertension. Fourteen days after MCT injection, male rats were treated orally for another 14 days with imatinib, statin or a combination of the two. RESULTS: Concurrent administration of statin (lipophilic simvastatin, hydrophilic rosuvastatin) and higher dose imatinib reversed the MCT-induced increase in RVP more than each drug alone and decreased RV hypertrophy (RV/LV+S ratio), significantly. The increased RVP and RV hypertrophy was found to be reversed when a lower dose of imatinib was co-administered with rosuvastatin or simvastatin. CONCLUSIONS: Statins may intensify the beneficial effects of imatinib in PAH, which may be due to the additional influence of statin on the decrease of platelet-derived growth factor (PDGF)-induced effects. These properties allow the dose of imatinib used in PAH treatment to be reduced and thereby might improve its safety profile.

Rosuvastatin, sildenafil and their combination in monocrotaline-induced pulmonary hypertension in rat.

There is considerable interest in the pleiotropic effects of statins and their potential role in the treatment of pulmonary hypertension. Previous experimental findings indicate that a combination of lipophilic statins with phosphodiesterase type-5 inhibitor, sildenafil, can offer preventive effects on rat monocrotaline-induced pulmonary hypertension. The present study is aimed to assess whether therapeutic regimen provides any benefits. Seven days after pulmonary hypertension induction, hydrophilic rosuvastatin and sildenafil were given for 14 days to male Wistar outbred rats. Right ventricular pressure, right ventricle mass and three biomarkers were evaluated after 21 days: brain natriuretic peptide, high-density lipoprotein cholesterol and vascular endothelial growth factor. The present study demonstrates that administration of hydrophilic statin with sildenafil results in reduction of pulmonary vascular remodeling and right ventricular pressure. The results of biochemical measurements may suggest that statins play a positive role in right ventricle function or the process of angiogenesis in pulmonary hypertension development.

Concurrent rho-kinase and tyrosine kinase platelet-derived growth factor inhibition in experimental pulmonary hypertension.

BACKGROUND: We hypothesized that inhibition of Rho-kinase by fasudil, together with tyrosine kinase platelet-derived growth factor (PDGF) receptor inhibition by imatinib, results in greater pulmonary arterial hypertension (PAH) improvement. METHODS: The effects of such regimens were investigated on hemodynamics, right ventricle hypertrophy, PDGF and ROCK in experimental monocrotaline (MCT)-induced pulmonary hypertension. Fourteen days after MCT injection, male rats were treated orally for another 14 days with imatinib, fasudil or their combination. RESULTS: Concurrent imatinib and fasudil administration reversed an MCT-induced increase in right ventricular pressure more than either drug alone and decreased right ventricle hypertrophy (right ventricle weight to left ventricle plus septum weight ratio) significantly. The simultaneous administration of fasudil and imatinib caused a further decrease in plasma PDGF-BB levels compared to either drug alone. CONCLUSIONS: Inhibition of Rho-kinase by fasudil in addition to tyrosine kinase PDGF inhibition by imatinib can result in further PAH improvement. Such outcome may result from additional impact of the Rho-kinase inhibitor on the decrease in PDGF-induced effects.

The beneficial impact of fasudil and sildenafil on monocrotaline-induced pulmonary hypertension in rats: a hemodynamic and biochemical study.

Pulmonary arterial hypertension (PAH) still cannot be cured effectively, hence the search for novel treatments continues. The effects of sildenafil (25 mg/kg body weight) and fasudil (30 mg/kg body weight) given alone or in combination, on normalization of right ventricular pressure (RVP), right ventricle mass, as well as the levels of several biomarkers (HDL-C, BNP, VEGF-A), were assessed in a rat model of monocrotaline (MCT)-induced PAH. MCT (60 mg/kg body weight) induced clear PAH in male Wistar rats. After 21 days, a significant decrease in RVP accompanied by a reduction of right ventricular hypertrophy - a significant decrease in the right ventricle/left ventricle plus septum ratio - as a result of sildenafil or fasudil administration was assessed. The administration of fasudil and sildenafil alone or in combination caused a significant decrease in plasma BNP level as compared to MCT-treated rats. Fasudil alone or with sildenafil, but not sildenafil alone, significantly increased HDL-C level as compared to MCT-treated rats. Fasudil and sildenafil given alone or in combination caused a significant increase in plasma VEGF-A level as compared to rats exposed to MCT.

Concomitant administration of simvastatin with ivabradine in contrast to metoprolol intensifies slowing of heart rate in normo- and hypercholesterolemic rats.

INTRODUCTION: ß-Blockers play a significant role in therapeutic heart rate (HR) management and angina control. In patients who are unable to tolerate ß-blockers ivabradine could be particularly useful. The aim of the study was to establish whether concomitant administration of simvastatin with ivabradine or metoprolol had any effect on rat HR and blood pressure (BP). MATERIAL AND METHODS: The experiments were performed in hyper- and normocholesterolemic outbred Wistar rats. Animals were divided into 2 groups: receiving during 4 weeks normal diet (normocholesterolemic rats) or diet with 5% cholesterol and 2.5% cholic acid (hypercholesterolemic rats). Then rats received placebo (0.1% methylcellulose), 2) metoprolol 30 mg/kg bw; 3) ivabradine 10 mg/kg bw; 4) simvastatin 10 mg/kg bw; 5) simvastatin 10 mg/kg bw + metoprolol 30 mg/kg bw; 6) simvastatin 10 mg/kg bw + ivabradine 10 mg/kg bw. Drugs were given during a 4-week period. HR and BP measure were provided by an Isotec pressure transducer connected to a direct current bridge amplifier. For the further lipid profile examination, 0.25 ml of blood samples were taken. RESULTS: After administration of ivabradine with simvastatin to normocholesterolemic and hypercholesterolemic rats the mean HR was significantly reduced as compared to rats receiving simvastatin (312.0 ±30.2 min(-1) vs. 430.7 ±27.8 min(-1), p<0.05); (329.8 ±24.2 min(-1) vs. 420.5 ±9.2 min(-1), p<0.05) or ivabradine alone (312.0 ±30.2 min(-1) vs. 350.2 ±16.0 min(-1), p<0.05); (329.8 ±24.2 min(-1) vs. 363.0 ±21.7 min(-1), p<0.05). CONCLUSIONS: Concomitant administration of simvastatin with ivabradine intensified slowing of HR, although it did not influence BP in normo-and hypercholesterolemic rats. Statin-induced intensification of HR deceleration after metoprolol administration was not observed.

Concomitant administration of different doses of simvastatin with ivabradine influence on PAI-1 and heart rate in normo- and hypercholesterolaemic rats.

Ivabradine is a novel heart rate lowering agent that inhibits I(f) ionic current in the sinus node and demonstrates antiischaemic and antianginal activity. The aim of the paper was to investigate the effect its dose-dependent drug-drug interaction with simvastatin inhibitor HMGCo-A has on PAI-1 blood level, heart rate and blood pressure. The experiments were performed in hyper- and normocholesterolemic Wistar rats receiving simvastatin (1 and 20 mg × kg(-1) bw) with ivabradine (10 mg × kg(-1) bw) during a 4-week period. Ivabradine exacerbated the decrease of PAI-1 in normocholesterolemic animals receiving simvastatin at a dose of 1 mg/kg bw and was not observed to have any significant influence on the PAI-1 values in rats receiving 20 mg × kg(-1) bw simvastatin. Ivabradine, coadministered with simvastatin given at a dose of 20 mg × kg(-1) bw, significantly slowed the heart rate in normocholesterolaemic and hypercholesterolaemic groups as compared to the group receiving ivabradine alone. Conclusion. The administration of ivabradine to normocholesterolaemic and hypercholesterolaemic rats receiving simvastatin significantly exacerbated the slowing of heart rate with no effect on blood pressure. The administration of ivabradine has been shown to demonstrate different effects on PAI-1 values depending on lipid disorders.

Effects of 4-week administration of simvastatin in different doses on heart rate and blood pressure after metoprolol injection in normocholesterolaemic and normotensive rats.

INTRODUCTION: Statins and ß1-adrenergic antagonists are well established in cardiovascular events therapy and prevention. The previous study showed that statins might impact on ß-adrenergic signalling and blood pressure in a dose-dependent manner. The aim of the study was to evaluate the impact of 4-week administration of simvastatin given at different doses on the heart rate and blood pressure after injection of metoprolol in rats. MATERIAL AND METHODS: The experiments were performed in normocholesterolaemic and normotensive Wistar rats. Rats received simvastatin in doses of 1, 10 and 20 mg/kg body weight (bw) for 4 weeks. The control group received 0.2% methylcellulose. For the further estimation of the heart rate and blood pressure, metoprolol at 5 mg/kg bw or 0.9% NaCl was injected intraperitoneally. RESULTS: Simvastatin at doses of 1, 10 and 20 mg/kg bw did not influence the heart rate or blood pressure as compared to the control group. Metoprolol injection statistically significantly decreased the heart rate (439.29±14.03 min(-1) vs. 374.41±13.32 min(-1); p<0.05). In rats receiving simvastatin during the 4-week period after metoprolol injection, heart rate and blood pressure (mean, systolic, diastolic) were similar as compared to the group receiving metoprolol alone. CONCLUSIONS: Simvastatin administration during a 4-week period in different doses did not influence the heart rate or blood pressure after metoprolol injection in normocholesterolaemic and normotensive rats.

Novel mechanistic and clinical implications concerning the safety of statin discontinuation.

The beneficial effects of statins have been discussed widely, and their preventative role has been confirmed in cardiovascular disorders, primary and secondary prevention settings, and in asymptomatic subjects with a high cardiovascular risk. Despite these benefits, discontinuation of statins is frequent in cardiac patients and might be associated with adverse outcomes in several conditions involving acute coronary syndromes or acute stroke. In this review, we focus on the mechanistic background of statins that might contribute to such negative changes and that extend beyond cholesterol-lowering effects, including the so-called pleiotropic statin activity. In particular, findings regarding the detrimental impact of statin withdrawal on endothelial function, inflammation, platelet activity or AT1 signaling are discussed, along with the possible clinical implications for statin safety.