Comparison of effects of simvastatin versus atorvastatin on oxidative stress in patients with coronary heart disease

The Antinociceptive Effects of Combined Treatment With Atorvastatin and Vitamin C in the Chronic Constriction Injury Model of Rats

Introduction

Neuropathic pain (NP) is caused by damage to the somatosensory system. Nerve damage often results in chronic pain states, including hyperalgesia and allodynia. This study aims to evaluate the anti-nociceptive effects of atorvastatin, vitamin C, and their combination on various laboratory tests in an experimental model NP in rats.

Methods

To assess the analgesic effects of atorvastatin (5 and 10 mg/kg), vitamin C (500 mg/kg), and their co-administration on chronic constriction injury (CCI) was induced in rats. Behavioral tests, motor nerve conduction velocity (MNCV), pro-inflammatory cytokines, and oxidative markers were measured. Furthermore, histopathological examination was performed.

Results

In the present study, it was found that the CCI model can significantly cause hyperalgesia and allodynia on the 21st postoperative day. It was found that the co-administration of vitamin C and atorvastatin has attenuating effects on allodynia and hyperalgesia. Co-administration of vitamin C and atorvastatin also improved MNCV. In the treatment groups, the inflammatory reactions and oxidative markers decreased. Moreover, the co-administration of atorvastatin and vitamin C decreased the perineural inflammation around the sciatic nerve.

Conclusion

The results of this study showed that vitamin C potentiates the analgesic effects of atorvastatin in this model of experimental pain, and simultaneous consumption of these medications may be considered as effective therapeutics for NP. The protective properties of atorvastatin, and vitamin C, and their combination on the NP that were assessed can be regarded as a novelty for this study.

Highlights

The co-administration of atorvastatin and vitamin C significantly decreases inflammatory cytokines.The co-administration of atorvastatin and vitamin C significantly decreases stress oxidant markers.The co-administration of atorvastatin and vitamin C significantly attenuated nociceptive effects.

Plain Language Summary

Nerve damage causes the deposition of inflammatory factors and or oxidative stress at the site of injury, which in turn activates glial cells that are involved in increasing the inflammatory process by producing and releasing pro-inflammatory agents and oxidative stress. Among statins, atorvastatin is a drug to reduce inflammation, and its effectiveness has been recorded as an antioxidant effect. Vitamin C is known as a neuroprotective agent. Ascorbate inhibits the production of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in monocytes in high doses (20 mM) by inhibiting them. The rats were randomly divided into 7 groups of 10 animals as follows: 1: Sham-operated, 2: Chronic constriction injury (CCI), 3: CCI+vitamin C (500 mg/kg), 4: CCI+atorvastatin (5 mg/kg), 5: CCI+atorvastatin (10 mg/kg), 6: CCI+vitamin C (500 mg/kg)+atorvastatin (5 mg/kg), and 7: CCI+vitamin C (500 mg/kg)+atorvastatin (10 mg/kg). The results of the present study indicated that the anti-inflammatory, antioxidant, and neuroprotective properties of vitamin C and atorvastatin improved the effects of CCI in an empirical neuropathic in rats. Moreover, it was shown that the associated treatment with vitamin C and atorvastatin can reduce inflammatory factors, such as TNF-α and IL-6, and oxidative markers, such as glutathione peroxidase (GPx), superoxide dismutase (SOD), and malonaldehyde (MDA), while the nerve conduction velocity enhanced and inflammation decreased in histology studies in CCI rats.

Could a lipid oxidative biomarker be applied to improve risk stratification in the prevention of cardiovascular disease?

There is significant evidence demonstrating the influence of oxidative stress on atherosclerosis and cardiovascular diseases (CVD). However, oxidative biomarkers have not been applied to follow patients under primary or secondary prevention. Many factors can explain this paradox: the higher complexity of the methods applied to quantify oxidative markers, the high variability observed among the studies, the lack of reference values, and the weak correlation with clinical endpoints. This review presents the role of the major reactive oxygen species (ROS) involved in cardiovascular pathophysiology and how they can be neutralized by endogenous and exogenous antioxidants based on classical and recent studies, highlighting the importance of the secondary products of fatty acid oxidation as potential biomarkers. Furthermore, we discuss the great variability of oxidative stress biomarkers, using as an example data obtained from 55 studies. Among the molecules directly formed from lipid oxidation, such as malondialdehyde (MDA), oxidized LDL (oxLDL), and isoprostanes (F₂-IsoP), and those associated with general oxidative conditions (ferric-reducing antioxidant power (FRAP), superoxide dismutase (SOD), glutathione (GSH)), MDA was the most lipid biomarker evaluated in the treatments and proved to be an independent factor compared with traditional markers used in the algorithms to stratify the patient's risk. Finally, this review suggests four steps to follow, aiming to include MDA in the algorithms applied to estimate CVD risk.

Effect of Moderate Wine Consumption on Oxidative Stress Markers in Coronary Heart Disease Patients

Evidence from research studies reports that wine consumption is associated with lower cardiovascular disease risk, partly through the amelioration of oxidative stress. The aim of the present study was to examine the effect of regular light to moderate wine consumption from coronary heart disease (CHD) patients compared to the effect induced by alcohol intake without the presence of wine microconstituents, on oxidation-induced macromolecular damage as well as on endogenous antioxidant enzyme activity. A randomized, single-blind, controlled, three-arm parallel intervention was carried out, in which 64 CHD patients were allocated to three intervention groups. Group A consumed no alcohol, and Group B (wine) and Group C (ethanol) consumed 27 g of alcohol/day for 8 weeks. Blood and urine samples were collected at baseline and at 4 and 8 weeks. Urine oxidized guanine species levels, protein carbonyls, thiobarbituric acid substances (TBARS) levels, as well as superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, were measured. Oxidized guanine species and protein carbonyl levels were significantly increased in the ethanol group during the intervention and were significantly decreased in the wine group. These results support the idea that wine’s bioactive compounds may exert antioxidant actions that counteract the macromolecular oxidative damage induced by alcohol in CHD patients.

Simvastatin ameliorates oxidative stress levels in HepG2 cells and hyperlipidemic rats

Simvastatin is an established anti-hyperlipidemic drug and few studies have indicated its role in the mitigation of oxidative stress. However, a systematic study considering molecular binding/interaction of simvastatin with anti-oxidant enzymes followed by confirmational in vitro and in vivo studies have never been done. We investigated the molecular binding of simvastatin with multiple anti-oxidant enzymes and assessed their levels after the treatment of simvastatin in vitro and in vivo. This study is the first to show the molecular binding of simvastatin to catalase through molecular docking analysis. Moreover, the anti-oxidative properties of simvastatin have not been studied in Lipopolysaccharide (LPS) induced oxidative stress in HepG2 cells. We found that simvastatin effectively attenuated oxidative stress in LPS induced HepG2 cells and high-fat diet (HFD) fed hyperlipidemic rats by increasing the levels of antioxidant enzymes. The activity of catalase and superoxide dismutase (SOD) both increased significantly in oxidatively stressed HepG2 cells after the treatment with simvastatin (10 ​μM, 24 ​h). In addition to this, he original cell morphology of oxidatively stressed cells was restored by simvastatin, and an increase in antioxidant enzymes, catalase (0.08 U/cells to 0.12 U/cells), and SOD (0.57 U/cells to 0.74 U/cells) was also noted in HepG2 cells. Furthermore, a significant increase in the antioxidant enzymes such as Catalase, SOD, and reduced glutathione (GSH) was noted after simvastatin treatment in the HFD model. Moreover, we also observed degradation of by-products of lipid peroxidation thiobarbituric acid reactive substances (TBARs), nitric oxide (NO), and protein carbonyl levels. This indicates that simvastatin enhances anti-oxidant enzyme activities and can be repurposed for the treatment of oxidative stress in liver diseases in humans after extensive clinical trials.

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In silico, molecular docking analysis shows that simvastatin binds to the active site of the catalase enzyme.

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Simvastatin attenuates LPS induced oxidative stress in HepG2 cells by increasing the amount of antioxidant enzymes catalase and SOD.

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Simvastatin significantly reduces triglycerides, cholesterol, LDL, VLDL, and increases HDL level in HFD induced oxidative stress in Wistar rats.

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Simvastatin can be repurposed for the treatment of oxidative stress in liver diseases.

Roles of Simvastatin and Sildenafil in Modulation of Cranial Irradiation-Induced Bystander Multiple Organs Injury in Rats

In radiobiology and radiation oncology fields, the observation of a phenomenon called radiation-induced bystander effect (RIBE) has introduced the prospect of remotely located tissues' affection. This phenomenon has been broadly developed to involve the concept of RIBE, which are relevant to the radiation-induced response of a distant tissue other than the irradiated one. The current study aimed at investigating each of the RIBE of cranial irradiation on oxidative and inflammatory status in different organs such as liver, kidney, heart, lung, and spleen. Being a vital target of the cholinergic anti-inflammatory response to an inflammatory stimulus, the splenic α-7-nicotinic acetylcholine receptor (α-7nAchR) was evaluated and the hepatic contents of thioredoxin, peroxisome proliferator-activated receptor-alpha and paraoxinase-1 (Trx/PPAR-α/PON) were also assessed as indicators for the liver oxidative stress and inflammatory responses. Being reported to act as antioxidant and anti-inflammatory agents, simvastatin (SV) and/or sildenafil (SD) were investigated for their effects against RIBE on these organs. These objectives were achieved via the biochemical assessments and the histopathological tissues examinations. Five experimental groups, one sham irradiated and four irradiated groups, were exposed to cranial irradiation at dose level of 25 Gy using an experimental irradiator with a Cobalt (Co60) source, RIBE, RIBE + SV (20 mg.(kg.bw)-1 day-1), RIBE + SD (75 mg.(kg.bw)-1 day-1), and RIBE + SV + SD. Cranial irradiation induced structural, biochemical, and functional dys-regulations in non-targeted organs. RIBE-induced organs' injuries have been significantly corrected by the administration of SV and/or SD. Our results suggest the possibility of a potentiated interaction between SV and SD in the modulation of the RIBE associated with head and neck radiotherapy.

The role of anti-proliferative effects of atorvastatin on uterine fibroids: findings from a clinical study

AIM

Uterine myomas/fibroids are one of the most common benign tumors of the reproductive system in women. Given pleiotropic effects of statins, the aim of this study is to evaluate the therapeutic effects of atorvastatin on uterine fibroids in women of reproductive age.

MATERIALS AND METHODS

This randomized clinical study included 90 women aged 35-45 years with uterine fibroids. The patients were randomly allocated into the intervention group (received one tablet, 20 mg of atorvastatin every day for three months) and placebo. Ultrasound was performed every month, and the change in the size of fibroids was recorded for each patient. At the end of the study, the data obtained were analyzed using SPSSv22 and a p value < .05 was considered statistically significant.

RESULTS

The mean age in the placebo and intervention group was 39.63 ± 36.3 and 40.35 ± 3.32 years, respectively. The number and location of the tumor was comparable for the two groups. We observed a statically significant reduction in fibroid size from the treatment initiation until completion of three months, (41.06 ± 6.68 mm³ vs 35.16 ± 6.67 mm³) p = .0001. However, the decrease in fibroid size from 1st month to the 3rd month was not statistically significant, p = .189 (36.71 ± 5.54 mm³ vs 35.16 ± 6.67 mm³).

CONCLUSION

This study shows that treatment with atorvastatin might positively reduce the size of fibroids. The decrease was only statistically significant during the first month. Further studies with a detailed analysis of the intervention's clinical impact are required to consider statins as a therapeutic tool.

Statins: Neurobiological underpinnings and mechanisms in mood disorders

Statins (3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors) treat dyslipidaemia and cardiovascular disease by inhibiting cholesterol biosynthesis. They also have immunomodulatory and anti-inflammatory properties. Beyond cardiovascular disease, cholesterol and inflammation appear to be components of the pathogenesis and pathophysiology of neuropsychiatric disorders. Statins may therefore afford some therapeutic benefit in mood disorders. In this paper, we review the pathophysiology of mood disorders with a focus on pharmacologically relevant pathways, using major depressive disorder and bipolar disorder as exemplars. Statins are discussed in the context of these disorders, with particular focus on the putative mechanisms involved in their anti-inflammatory and immunomodulatory effects. Recent clinical data suggest that statins may have antidepressant properties, however given their interactions with many known biological pathways, it has not been fully elucidated which of these are the major determinants of clinical outcomes in mood disorders. Moreover, it remains unclear what the appropriate dose, or appropriate patient phenotype for adjunctive treatment may be. High quality randomised control trials in concert with complementary biological investigations are needed if the potential clinical effects of statins on mood disorders, as well as their biological correlates, are to be better understood.

PCSK9 inhibitor effectively attenuates cardiometabolic impairment in obese-insulin resistant rats

Long-term high-fat diet consumption causes obese-insulin resistance and cardiac mitochondrial dysfunction, leading to impaired left ventricular (LV) function. Atorvastatin effectively improved lipid profiles in obese patients. However, inadequate reduction in low density lipoprotein cholesterol (LDL-C) level was found. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor effectively reduced LDL-C levels. We hypothesized that this PCSK9 inhibitor has a greater efficacy in attenuating cardiometabolic impairments than atorvastatin in obese-insulin resistant rats. Female rats were fed with either a high fat or normal diet for 12 weeks. High fat diet fed rats (HFD) were then divided into 3 groups and were given vehicle, atorvastatin (40 mg/kg/day; s.c.), or PCSK9 inhibitor (4 mg/kg/day; s.c.) for additional 3 weeks. The metabolic parameters, cardiac and mitochondrial function and [Ca²⁺]_i transients were determined. HFD rats developed obese-insulin resistance as indicated by increased plasma insulin and HOMA index. Although high-fat diet fed rats treated with vehicle (HFV) rats had markedly impaired LV function as indicated by reduced %LVFS, impaired cardiac mitochondrial function, and [Ca²⁺]_i transient regulation, these impairments were attenuated in high-fat diet fed rats treated with atorvastatin (HFA) and high-fat diet fed rats treated with PCSK9 inhibitor (HFP) rats. However, these improvements were greater in HFP rats than HFA rats. Our findings indicated that the PCSK9 inhibitor exerted greater cardioprotection than atorvastatin through improved mitochondrial function in obese-insulin resistant rats.

PCSK9 inhibitor and atorvastatin reduce cardiac impairment in ovariectomized prediabetic rats via improved mitochondrial function and Ca2+ regulation

Post‐menopausal women have a higher risk of developing cardiometabolic dysfunction. Atorvastatin attenuates dyslipidaemia and cardiac dysfunction but it can have undesirable effects including increased risk of diabetes and myalgia. Currently, the proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor efficiently reduces low‐density lipoprotein cholesterol (LDL‐C) levels more effectively than atorvastatin. We have been suggested that PCSK9 inhibitor attenuated cardiometabolic impairment more effectively than atorvastatin in ovariectomized prediabetic rats. Female Wistar rats (n = 48) were fed a normal diet (ND) or high‐fat diet (HFD) for 12 weeks. Then, HFD rats were assigned to a sham‐operated (Sham) or ovariectomized (OVX) group. Six weeks after surgery, the OVX group was subdivided into 4 treatment groups: vehicle (HFOV), atorvastatin (HFOA) (40 mg/kg/day; s.c.), PCSK9 inhibitor (HFOP) (4 mg/kg/day; s.c.) and oestrogen (HFOE₂) (50 µg/kg/day; s.c.) for an additional 3 weeks. Metabolic parameters, cardiac and mitochondrial function, and [Ca²⁺]_i transients were evaluated. All HFD rats became obese‐insulin resistant. HFS rats had significantly impaired left ventricular (LV) function, cardiac mitochondrial function and [Ca²⁺]_i transient dysregulation. Oestrogen deprivation (HFOV) aggravated all of these impairments. Our findings indicated that the atorvastatin, PCSK9 inhibitor and oestrogen shared similar efficacy in the attenuation in cardiometabolic impairment in ovariectomized prediabetic rats.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor exerts greater efficacy than atorvastatin on improvement of brain function and cognition in obese rats

The accumulation of lipid as a result of long-term consumption of a high-fat diet (HFD) may lead to metabolic and brain dysfunction. Atorvastatin, a recommended first-line lipid-lowering agent, has shown beneficial effects on metabolic and brain functions in several models. Recently, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor was approved as an effective therapeutic drug for dyslipidemia patients. However, few studies have reported on the effect of this PCSK9 inhibitor on brain function. In addition, the comparative efficacy on the improvement of metabolic and brain functions between PCSK9 inhibitor and atorvastatin in obese models have not been elucidated. We hypothesized that PCSK9 inhibitor improves metabolic and brain functions in an obese model to a greater extent than atorvastatin. Thirty-two female rats were fed with either a normal diet (ND) or HFD for 15 weeks. At week 13, ND rats were given normal saline and HFD rats were given either normal saline, atorvastatin (40 mg/kg/day) or PCSK9 inhibitor (4 mg/kg/day) for 3 weeks. Oxidative stress, blood brain barrier breakdown, microglial hyperactivity, synaptic dysplasticity, apoptosis, amyloid proteins production in the hippocampus and cognitive decline were found in HFD-fed rats. Atorvastatin and PCSK9 inhibitor therapies equally attenuated hippocampal apoptosis and amyloid protein production in HFD-fed rats. Interestingly, PCSK9 inhibitor had the greater efficacy than atorvastatin on the amelioration of hippocampal oxidative stress, blood brain barrier breakdown, microglial hyperactivity, synaptic dysplasticity in the hippocampus and cognitive decline. These findings suggest that PCSK9 inhibitor may be another drug of choice for improving brain function in the obese condition with discontinued statin therapy.

Anti-inflammatory latex proteins of the medicinal plant Calotropis procera: a promising alternative for oral mucositis treatment

OBJECTIVE AND DESIGN

Oral mucositis (OM) is an intense inflammatory reaction progressing to tissue damage and ulceration. The medicinal uses of Calotropis procera are supported by anti-inflammatory capacity. PII-IAA, a highly homogenous cocktail of laticifer proteins (LP) prepared from the latex of C. procera, with recognized pharmacological properties was tested to treat OM.

MATERIALS AND SUBJECTS

Male Golden Sirius hamsters were used in all treatments.

TREATMENT

The latex protein samples were injected i.p. (5 mg/Kg) 24 h before mucositis induction (mechanical trauma) and 24 h later.

METHODS

Histology, cytokine measurements [ELISA], and macroscopic evaluation [scores] were performed.

RESULTS

PII-IAA eliminated OM, accompanied by total disappearance of myeloperoxidase activity and release of IL-1b, as well as reduced TNF-a. Oxidative stress was relieved by PII-IAA treatment, as revealed by MDA and GSH measurements. PII-IAA also reduced the expression of adhesion molecules (ICAM-1) and Iba-1, two important markers of inflammation, indicating modulatory effects. Histological analyses of the cheek epithelium revealed greater deposition of type I collagen fibers in animals given PII-IAA compared with the control group. This performance was only reached when LPPII was treated with iodoacetamide (IAA), an irreversible inhibitor of proteolytic activity of cysteine proteases. The endogenous proteolytic activity of LPPII induced adverse effects in animals. Candidate proteins involved in the phytomodulatory activity are proposed.

CONCLUSIONS

Therapy was successful in treating OM with the laticifer protein fraction, containing peptidases and osmotin, from Calotropis procera. The effective candidate from the latex proteins for therapeutic use is PII-IAA.

Crataegus Aronia protects and reverses vascular inflammation in a high fat diet rat model by an antioxidant mechanism and modulating serum levels of oxidized low-density lipoprotein

CONTEXT

Crataegus aronia (Willd.) Bosc (Rosaceae) (syn. Azarolus L) is traditionally used to treat cardiovascular disorders.

OBJECTIVES

To investigate C. aronia protection against a high-fat diet (HFD)-induced vascular inflammation in rats.

MATERIALS AND METHODS

Wistar Male rats (180-220 g) were divided (n = 10/group) as control fed a standard diet (STD), STD + C. aronia (200 mg/kg, orally), HFD, HFD + C. aronia and HFD post-treated with C. aronia. Simvastatin (20 mg/kg) was co- or post-administered as a positive control drug. HFD was given for 8 weeks, and all other treatments were administered for 4 weeks.

RESULTS

Most significantly, co-administration of C. aronia to HFD-fed rats reduced the thickness of aorta tunica media (90 ± 5 vs. 160 ± 11.3 µm) and adventitia (54.3 ± 3.8 vs. 93.6 ± 9.4 µm). It also lowered protein levels of TNF-α (0.51 ± 0.15 and 0.15 ± 0.16 vs. 0.1 ± 0.09%) and IL-6 (0.52 ± 0.19 vs. 1.0 ± 0.2%) in their aorta or serum (5.9 ± 0.91 vs. 12.98 ± 1.3 ng/mL and 78.1 ± 6.7 vs. 439 ± 78 pg/mL, respectively). It also lowered all serum lipids and increased aorta levels of GSH levels (70.4 ± 4.0 vs. 40.7 µM) and activity of SOD (5.7 ± 0.7 vs. 2.9 ± 0.6 U/mg) and decreased serum levels of ox-LDL-c (566.7 ± 46 vs. 1817 ± 147 ng/mL). Such effects were more profound than all other treatments.

CONCLUSIONS

C. aronia inhibits the HFD-induced vascular inflammation and its use in clinical trials is recommended.

Simvastatin improves olanzapine-induced dyslipidemia in rats through inhibiting hepatic mTOR signaling pathway

Second-generation antipsychotic drug (SGA)-induced metabolic abnormalities, such as dyslipidemia, are a major clinical problem for antipsychotic therapy. Accumulated evidences have shown the efficacy of statins in reducing SGA-induced dyslipidemia, but the underlying mechanisms are unclear. In this study, we explored whether mTOR signaling was involved in olanzapine (OLZ)-induced dyslipidemia as well as the lipid-lowering effects of cotreatment of simvastatin (Sim) in rats. Model rats received OLZ (1.0 mg/kg, t.i.d.) for 7 weeks; from the third week a group of model rats were cotreatment of Sim (3.0 mg/kg, t.i.d.) for 5 weeks. We found that OLZ treatment significantly increased the plasma triglyceride (TG) and total cholesterol (TC) levels, and promoted lipid accumulation in the liver, whereas cotreatment of Sim reversed OLZ-induced dyslipidemia. Hepatic mTORC1 and p-mTORC1 expression was accelerated in the OLZ treatment group, with upregulation of mRNA expression of sterol regulatory element-binding protein 1c (SREBP1c) and its target genes, whereas these alterations were ameliorated by Sim cotreatment. In HepG2 cells, rapamycin (a mTOR inhibitor) significantly reduced the OLZ-stimulated hepatocellular lipid contents and weakened the ability of Sim to lower lipids via a mechanism associated with the upregulation of SREBP1c-mediated de novo lipogenesis. Our data suggest that OLZ induces lipid accumulation in both plasma and liver, and Sim ameliorates OLZ-induced lipid metabolic dysfunction through its effects on mTOR signaling via reducing SREBP1c activation and the downregulation of gene expression involved in lipogenesis. These data provide a new insight into the prevention of metabolic side effects induced by antipsychotic drugs.

Effect of statin treatment on circulating malondialdehyde concentrations: a systematic review and meta-analysis

Background

The effect of statins on oxidative stress markers, such as malondialdehyde (MDA), is still a matter of debate. We sought to address this issue by conducting a systematic review and meta-analysis of published data on the effect of statin treatment on systemic MDA concentrations.

Methods

A literature search was conducted on MEDLINE/PubMed, ISI Web of Sciences and Scopus. Data were pooled using a random-effects model.

Results

A total of 35 studies assessing MDA concentrations before and after statin treatment in 1512 participants (mean age 53.6 years, 48.7% males) were identified. Extreme between-study heterogeneity was observed (I² = 96.0%, p < 0.001). Pooled standardized mean difference (SMD) showed a significant reduction in plasma MDA concentrations after treatment (SMD = -1.47 µmol/l, 95% confidence interval = -1.89 to -1.05 μmol/l; p < 0.001). Similarly, a subgroup analysis of 10 studies that also included a placebo group showed a significant reduction in plasma MDA concentrations with statins (-1.03 μmol/l, 95% confidence interval = -1.52 to -0.29 μmol/l; p = 0.036).

Conclusions

This systematic review and meta-analysis showed that statin treatment significantly reduces systemic MDA concentrations. However, the results should be interpreted with caution because of extreme between-study heterogeneity, which warrants further intervention studies.

Protective effect of atorvastatin on oxidative stress in streptozotocin-induced diabetic rats independently their lipid-lowering effects

In the present study, we investigate the effects of atorvastatin on the lipid profile, oxidative stress, and liver enzyme markers, and its protective activity against diabetic complications, in streptozotocin (STZ)-induced diabetic rats. Fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), and high-density lipoprotein (HDL) levels, as well as alanine aminotransferase (ALT) and aspartate aminotransferase (AST) enzyme activities, were measured 7 weeks after the administration of STZ and atorvastatin. Thiobarbituric acid reactive substances (TBARS), non-protein associated sulfhydryl (NP-SH), total sulfhydryl (T-SH), and nitric oxide (NO) levels were measured to evaluate oxidative stress. Atorvastatin was found to inhibit ALT and AST activities and to reduce FBG levels in rats with STZ-induced diabetes. Moreover, atorvastatin treatment significantly reduced lipid peroxidation in kidney, heart, and eye tissues (P < 0.001, for all), and resulted in a significant increase in NP-SH levels in brain tissues (P < 0.001). Total NO and nitrate levels increased significantly after atorvastatin treatment (P < 0.01). Our results revealed that atorvastatin has a protective effect against STZ-induced oxidative damage by reducing TBARS levels and increasing NP-SH levels, has a hepatoprotective effect by decreasing ALT and AST activities. It also shows the antihyperglycemic activity by lowering FBG levels.

Efficiency of atorvastatin and simvastatin in improving cardiac function during the different degrees of hyperhomocysteinemia

The aim of this study was to assess the impact of atorvastatin and simvastatin on myocardial contractility during the different degrees of hyperhomocysteinemia (HHcy) in rats. Study was conducted on adult male Wistar albino rats (n = 90; 4 weeks old; 100 ± 15 g body mass) in which HHcy was achieved by dietary manipulation. Animals were exposed to pharmacology treatment with atorvastatin in dose of 3 mg/kg per day i.p. or simvastatin in dose of 5 mg/kg per day i.p. at the same time every day, according to equivalent therapeutic doses of these statins (10 mg atorvastatin = 20 mg simvastatin). After the dietary manipulation and pharmacological treatment and confirmation of HHcy, all animals were sacrificed, hearts were isolated, and cardiac function was tested according to the Langendorff technique. Size of recovery of maximum rate of left ventricular development (dp/dtmax), minimum rate of left ventricular development (dp/dtmin), systolic left ventricular development, diastolic left ventricular development, heart rate, and coronary flow at the 40, 60, 80, 100, and 120 cmH2O coronary perfusion pressure were measured in state of physiological condition (homocysteine less than 15 μmol/L), mild HHcy, and moderate HHcy. Atorvastatin treatment significantly attenuated homocysteine-induced impairment of myocyte contractility and dominantly decreased dp/dtmax, dp/dtmin, and heart rate and induced greater changes in systolic left ventricular development compared with simvastatin. Treatment with atorvastatin seems able to revert systolic abnormalities and improve contractility during the different degrees of HHcy.

Understanding mitochondrial biogenesis through energy sensing pathways and its translation in cardio-metabolic health

Mitochondria play a pivotal role in physiological energy governance. Mitochondrial biogenesis comprises growth and division of pre-existing mitochondria, triggered by environmental stressors such as endurance exercise, caloric restriction, cold exposure and oxidative stress. For normal physiology, balance between energy intake, storage and expenditure is of utmost important for the coordinated regulation of energy homeostasis. In contrast, abnormalities in these regulations render the individual susceptible to cardiometabolic disorders. This review provides a comprehensive coverage and understanding on mitochondrial biogenesis achieved through energy-sensing pathways. This includes the complex coordination of nuclear, cytosolic and mitochondrial events involving energy sensors, transcription factors, coactivators and regulators. It focuses on the importance of mitochondrial biogenesis in cardiometabolic health. Lastly, converging on the benefits of caloric restriction and endurance exercise in achieving cardiometabolic health.

The Effect of Atorvastatin on Obsessive-compulsive Symptoms of Refractory Obsessive-compulsive Disorder (Add-on Therapy)

Background

Considering the effect of statins on the regulation of dopamine neurotransmitters and glutamates and importance of the treatment of obsessive-compulsive disorder (OCD) due to its relatively high prevalence and disability of available drugs in treatment of many patients, we came to the point to examine effectiveness of statins in patients with OCD.

Materials and Methods

This study is a double-blind randomized clinical trial, which is done in OCD clinic of Isfahan Shariati in 2014 for 1 year. The target population consists of 64 patients with OCD; one group is given a daily 40 mg atorvastatin tablets and the other group receives placebo. At baseline, 4- and 8-week severities of obsessive-compulsive symptoms are measured using Yale-Brown scale and compared in the two groups.

Results

The study results show a statistically significant difference between the two groups of intervention and control (P < 0.001). Furthermore, the results show the intervention effect at the end of the 4^th week and 8^th week (P < 0.001) that this change is evident in the 4^th week but remained almost constant in the 8^th week.

Conclusion

Overall, the evidences obtained from the study declare the effects of adding statins to treat obsessive-compulsive symptoms.

Atorvastatin and insulin equally mitigate brain pathology in diabetic rats

Although insulin and atorvastatin have been shown to exert glycemic control and could improve brain function, the effects of atorvastatin or insulin as well as the combination of atorvastatin plus insulin on brain pathology in diabetes mellitus type 1 (T1DM) are unclear. Therefore, this study investigated the effect of atorvastatin, insulin or combined drugs on brain pathology in streptozotocin-induced diabetic rats. Thirty-six male rats were divided into two groups, a control group (n = 12) and a diabetic or experimental group (n = 24). Diabetic rats were further divided into four groups (n = 6/group) and the groups received either a vehicle (normal saline), atorvastatin (10 mg/kg/day), insulin (4 U/day) or a combination of the drugs for 4 weeks. The control group rats were divided into two groups (n = 6/group) to receive either just the vehicle or atorvastatin for 4 weeks. We found that streptozotocin-induced diabetic rats developed hyperglycemia, showing evidence of increased brain oxidative stress, impaired brain mitochondrial function, increased brain apoptosis, increased tau protein expression, increased phosphorylation of tau protein expression and amyloid beta levels, and decreased dendritic spine density. Although atorvastatin and insulin therapies led to an equal reduction in plasma glucose level in these diabetic rats, the combined drug therapy showed the greatest efficacy in decreasing plasma glucose level. Interestingly, atorvastatin, insulin and the combined drugs equally mitigated brain pathology. Our findings indicate that the combined drug therapy showed the greatest efficacy in improving metabolic parameters. However, atorvastatin, insulin and the combined drug therapy shared a similar efficacy in preventing brain damage in T1DM rats.

Oxidative stress and kidney injury in trans-radial catheterization

Oxidative stress is linked to coronary artery disease and is a major mechanism in contrast-induced nephropathy. Trans-radial approach in coronary angiography (CA) with minimized peri-procedural bleeding is expected to reduce acute kidney injury incidence. In the present study, oxidative stress patterns observed in radial CA and their associations with early manifestations of kidney injury are described. A total of 20 stable coronary disease patients submitted to CA and 17 sex-matched patients undergoing computed tomography for myoskeletal reasons were enrolled. Reduced glutathione, catalase, thiobarbituric acid reactive species (TBARS) levels and total anti-oxidant status were measured at various time points postangiography. In ischemic patients baseline TBARS levels were 2-fold lower compared to controls, while carbonyls levels were 35% higher. Glutathione was almost 4-fold lower than the control group. Glutathione and lipid peroxidation in ischemic patients gradually increased after contrast medium administration and reached 180% (P<0.001) and 20% (P=0.021) after 4–6 h, respectively. Four patients presented early evidence of contrast-induced nephropathy postangiography, while no control patient developed acute kidney injury. In the multiple logistic regression analysis, only the creatinine levels at baseline influenced the frequency of early contrast-induced nephropathy development (β =0.36, 95% CI: 0.285–0.438, P=0.01). Glutathione low levels were dominant in the baseline values of ischemic patients who developed contrast-induced nephropathy. Glutathione levels rapidly increased while protein oxidation decreased at the expense of lipid peroxidation. In conclusion, early oxidative stress changes occur in trans-radial CA patients with a mild profile, sufficient to mobilize patient antioxidant defenses.

Effects of atorvastatin and simvastatin on oxidative stress in diet-induced hyperhomocysteinemia in Wistar albino rats: a comparative study

Considering the well-known antioxidant properties of statins, it seems important to assess their impact on major markers of oxidative stress (superoxide anion radical, nitric oxide, and index of lipid peroxidation) to compare the antioxidative potentials of atorvastatin and simvastatin during the different degrees of hyperhomocysteinemia (HHcy) in rats. This study was conducted on adult male Wistar albino rats (n = 90; 4 weeks old; 100 ± 15 g body mass) in which HHcy was achieved by dietary manipulation. For 4 weeks, the animals were fed with one of the following diets: standard rodent chow, diet enriched in methionine with no deficiency in B vitamins (folic acid, B6, and B12), or diet enriched in methionine and deficient in B vitamins (folic acid, B6, and B12). At the same time, animals were treated with atorvastatin at doses of 3 mg/kg/day i.p. or simvastatin at doses of 5 mg/kg/day i.p. Levels of superoxide anion radical and TBARS were significantly decreased by administration of simvastatin in normal and high-homocysteine (Hcy) groups (p < 0.05). At 4 weeks after feeding with purified diets, the concentrations of the GSH, CAT, and SOD antioxidants were significantly affected among all groups (p < 0.05). Our results indicated that statin therapy had variable effects on the redox status in hyperhomocysteinemic rats, and simvastatin demonstrated stronger antioxidant effects than did atorvastatin.

Comparative evaluation of efficacy of subgingivally delivered 1.2% Atorvastatin and 1.2% Simvastatin in the treatment of intrabony defects in chronic periodontitis: a randomized controlled trial

Background. Statins are the recently evolved agents that aid in periodontal regeneration and ultimately in attaining periodontal health. Atorvastatin (ATV) and Simvastatin (SMV) are specific competitive inhibitors of 3-hydroxy-2-methyl-glutaryl coenzyme A reductase. The current study was conducted to compare the effectiveness of 1.2% ATV and 1.2% SMV, in addition to scaling and root planing (SRP), in the treatment of intrabony defects in subjects with chronic periodontitis. Methods. Ninety-six individuals were categorized into three treatment groups: SRP plus 1.2% ATV, SRP plus 1.2% SMV and SRP plus placebo. Clinical parameters of full-mouth plaque index (PI), modified sulcus bleeding index (mSBI), probing depth (PD), and relative attachment level (RAL) were recorded at baseline before SRP and at 3, 6 and 9 months. Bone fill was assessed using percentage radiographic defect depth reduction at baseline, 6 months and 9 months. Results. Both ATV and SMV showed significant PD reduction and RAL gain than placebo. ATV group showed greater mean PD reduction and mean RAL gain as compared to SMV group at 3, 6 and 9 months. Furthermore, ATV group sites exhibited a significantly greater percentage of radiographic defect depth reduction (33.23 ± 3.11%; 34.84 ± 3.07%) as compared to SMV (30.39 ± 3.36%; 32.15 ± 3.37%) at 6 and 9 months. Conclusion. ATV resulted in greater improvements in clinical parameters with higher percentage of radiographic defect depth reduction as compared to SMV in the treatment of intrabony defects in CP subjects.

Simvastatin enhances the hippocampal klotho in a rat model of streptozotocin-induced cognitive decline

Brain oxidative status is a crucial factor in the development of sporadic Alzheimer's disease (AD). Klotho, an anti-aging protein, diminishes oxidative stress by the induction of manganese superoxide dismutase (MnSOD). Thus, the substances that increase klotho expression could be considered as a potential treatment for Alzheimer's disease when the oxidative imbalance is present. Statins are suggested to up-regulate klotho expression. We examined the effect of simvastatin (5mg/kg, daily for 3weeks) on hippocampal klotho and MnSOD expression in the cognitive declined animal model induced by intracerebroventricular (ICV)-streptozotocin (STZ) administration. Cognitive assessment was performed by the Morris Water Maze (MWM) test. The results indicated that mean escape latency and distance were prolonged in the ICV-STZ group compared with the control group. The expression of klotho and MnSOD were also down regulated in the hippocampus. Furthermore, improved spatial performance was observed in simvastatin-treated animals. This effect could be related to increase in oxidative stress tolerance as evidenced by klotho and MnSOD up-regulation. Our current study indicates that klotho upregulation may be a neuroprotective mechanism of simvastatin against cognitive decline in AD.

Alternative Interventions to Prevent Oxidative Damage following Ischemia/Reperfusion

Ischemia/reperfusion (I/R) lesions are a phenomenon that occurs in multiple pathological states and results in a series of events that end in irreparable damage that severely affects the recovery and health of patients. The principal therapeutic approaches include preconditioning, postconditioning, and remote ischemic preconditioning, which when used separately do not have a great impact on patient mortality or prognosis. Oxidative stress is known to contribute to the damage caused by I/R; however, there are no pharmacological approaches to limit or prevent this. Here, we explain the relationship between I/R and the oxidative stress process and describe some pharmacological options that may target oxidative stress-states.

Platelet-Rich Fibrin Combined With 1.2% Atorvastatin for Treatment of Intrabony Defects in Chronic Periodontitis: A Randomized Controlled Clinical Trial

BACKGROUND

Platelet-rich fibrin (PRF), a second-generation platelet concentrate, and atorvastatin (ATV), a potent member of the statin group, are known to promote tissue regeneration. The current study is designed to evaluate combined efficacy of PRF and 1.2% ATV gel with open flap debridement (OFD) in treatment of intrabony defects (IBDs) in individuals with chronic periodontitis (CP).

METHODS

Ninety-six individuals with single defects were categorized into three groups: 1) OFD with PRF; 2) OFD with PRF + 1.2% ATV; and 3) OFD alone. Clinical parameters: 1) site-specific plaque index; 2) modified sulcus bleeding index; 3) probing depth (PD); 4) relative clinical attachment level (rCAL); and 5) gingival marginal level were recorded at baseline before surgery and 9 months postoperatively. Percentage radiographic IBD depth reduction was evaluated at baseline and 9 months.

RESULTS

PRF + 1.2% ATV and PRF alone showed significantly greater PD reduction and rCAL gain compared with OFD alone at 9 months. Furthermore, PRF + 1.2% ATV showed a similar percentage radiographic defect depth reduction (50.96% ± 4.88%) compared with PRF alone (47.91% ± 4.79%), and a greater reduction compared with OFD alone (5.54% ± 1.71%) at 9 months.

CONCLUSIONS

PRF + 1.2% ATV showed similar improvements in clinical parameters with a greater percentage radiographic defect depth reduction compared with PRF alone in treatment of IBDs in individuals with CP. Thus, 1.2% ATV failed to augment the regenerative potential of PRF alone in periodontal IBDs.

Simvastatin and oxidative stress in humans: A randomized, double-blinded, placebo-controlled clinical trial

Simvastatin reduces the blood concentration of cholesterol by inhibiting hydroxymethylglutaryl-coenzyme A reductase, the rate-limiting enzyme in cholesterol synthesis, and thereby reduces the risk of cardiovascular disease. In addition, simvastatin treatment leads to a reduction in fluxes in mitochondrial respiratory complexes I and II and might thereby reduce the formation of reactive oxygen species, which have been implicated in the pathogenesis of arteriosclerosis. Therefore, we hypothesized that simvastatin may reduce oxidative stress in humans in vivo.

We conducted a randomized, double-blinded, placebo-controlled study in which subjects were treated with either 40 mg of simvastatin or placebo for 14 days. The endpoints were six biomarkers for oxidative stress, which represent intracellular oxidative stress to nucleic acids, lipid peroxidation and plasma antioxidants, that were measured in urine and plasma samples.

A total of 40 participants were included, of which 39 completed the trial. The observed differences between simvastatin and placebo groups in the primary outcomes, DNA and RNA oxidation, were small and nonsignificant (p=0.68), specifically, 3% in the simvastatin group compared to 7.1% in the placebo group for DNA oxidation and 7.3% in the simvastatin group compared to 3.4% in the placebo group. The differences in biomarkers related to plasma were not statistically significant between the treatments groups, with the exception of total vitamin E levels, which, as expected, were reduced in parallel with the reduction in plasma cholesterol.

In healthy young male volunteers, short-term simvastatin treatment, which considerably reduces cholesterol, does not lead to a clinically relevant reduction in a panel of measures of oxidative stress. Whether simvastatin has effects on oxidative stress in diseased populations, such as diabetes or hemochromatosis, where oxidative stress is prominent, is unknown but seems unlikely.

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Simvastatin reduces plasma cholesterol but not oxidative stress.

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Oxidative stress was measured in both intracellular and extracellular compartments.

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Simvastatin does not influence nuclelic acid oxidation.

Omega 3 Fatty Acids Supplementation and Oxidative Stress in HIV-Seropositive Patients. A Clinical Trial

HIV-seropositive patients show high incidence of coronary heart disease and oxidative stress has been described as relevant key in atherosclerosis development. The aim of this study was to assess the effect of omega 3 fatty acids on different markers of oxidative stress in HIV-seropositive patients. We performed a randomized parallel controlled clinical trial in The Instituto Mexicano del Seguro Social, a public health hospital. 70 HIV-seropositive patients aged 20 to 55 on clinical score A1, A2, B1 or B2 receiving highly active antiretroviral therapy (HAART) were studied. They were randomly assigned to receive omega 3 fatty acids 2.4 g (Zonelabs, Marblehead MA) or placebo for 6 months. At baseline and at the end of the study, anthropometric measurements, lipid profile, glucose and stress oxidative levels [nitric oxide catabolites, lipoperoxides (malondialdehyde plus 4-hydroxialkenals), and glutathione] were evaluated. Principal HAART therapy was EFV/TDF/FTC (55%) and AZT/3TC/EFV (15%) without difference between groups. Treatment with omega 3 fatty acids as compared with placebo decreased triglycerides (-0.32 vs. 0.54 mmol/L; p = 0.04), but oxidative stress markers were not different between groups.

Elevated oxidative stress among coronary artery disease patients on statin therapy: A cross sectional study

BACKGROUND

Statins are a major group of drugs that reduces LDL-C levels, which are proven to have other beneficial effects such as preventing coronary events. The objective of this study was to evaluate oxidative stress and select novel coronary artery disease risk factors among coronary artery disease patients on statins.

METHODS

In this observational, cross-sectional study, we compared total cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol, apolipoprotein B, lipoprotein (a), homocysteine, reduced glutathione, glutathione peroxidase, superoxide dismutase, ascorbic acid, malondialdehyde and oxidized LDL among male coronary artery disease patients on statin therapy (group 2, n = 151) with sex-matched, diabetic patients (group 3, n = 80) as well as healthy controls (group 1, n = 84).

RESULTS

Total cholesterol, triglycerides, HDL-cholesterol and LDL-cholesterol were significantly lower among subjects of group 2 compared to other two groups. The novel risk factors studied did not differ significantly between groups, except for a higher homocysteine level among group 2 subjects compared to the other two groups. Elevated oxidative stress, indicated by lower reduced glutathione, glutathione peroxidase, and ascorbic acid as well as higher malondialdehyde and oxidized LDL was observed among group 2 subjects. Triglycerides, HDL-cholesterol, ascorbic acid and malondialdehyde were found to be independent predictors for coronary artery disease among this study population.

CONCLUSIONS

Though coronary artery disease subjects had healthy lipid profile, oxidative stress, a recognized risk factor for coronary events, was still elevated among this patient group. Novel risk factors were not found to be major predictors for coronary artery disease among the study subjects.

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.

Short term high dose atorvastatin for the prevention of contrast-induced nephropathy in patients undergoing computed tomography angiography

BACKGROUND

Statins are shown effective by some studies in preventing contrast-induced nephropathy (CIN). We evaluated the effectiveness of atorvastatin in the prevention of CIN in computed tomography angiography (CTA) candidates.

METHODS

This study was conducted on patients referring for elective CTA with normal renal function. Patients received atorvastatin (80 mg/day) or placebo from 24 h before to 48 h after administration of the contrast material. Serum creatinine was measured before and 48 h after contrast material injection. CIN was defined as an increase in serum creatinine level of ≥ 0.5 mg/dl or ≥ 25% of the baseline creatinine.

RESULTS

A total of 236 patients completed the study; 115 atorvastatin, 121 placebo, mean age = 58.40 ± 9.80 year, 68.6% male. Serum creatinine increased after contrast material injection in both the atorvastatin (1.00 ± 0.16-1.02 ± 0.15 mg/dl, P = 0.017) and placebo groups (1.03 ± 0.17-1.08 ± 0.18 mg/dl, P < 0.001). Controlling for age, gender, comorbidities, drug history, and baseline serum creatinine level, patients who received atorvastatin experienced less increase in serum creatinine after contrast material injection (beta = 0.127, P = 0.034). However, there was no difference between the atorvastatin and placebo groups in the incidence of CIN (4.3 vs. 5.0%, P = 0.535).

CONCLUSION

In patients undergoing CTA, a short-term treatment with high dose atorvastatin is effective in preventing contrast-induced renal dysfunction, in terms of less increase in serum creatinine level after contrast material injection. Further trials including larger sample of patients and longer follow-ups are warranted.

Statin Therapy for Primary Prevention of Atrial Fibrillation: Guided by CHADS2/CHA2DS2VASc Score

Atrial fibrillation (AF) is the most common arrhythmia and is associated with increased cardiovascular morbidity and mortality. The anti-arrhythmic effect of statins on AF prevention appears to be highly significant in most clinical studies. However, some discrepancies do exist among different clinical studies. Different clinical settings and types of stains used may explain these differences between trials. The CHADS₂ and CHA₂DS₂VASc scoring systems have been used for stroke risk stratification in AF patients. The recent study suggested that these scores can also be used to guide statin therapy for AF prevention. Patients with higher scores had a higher risk of developing AF and gained more benefits from statins therapy than those with lower scores. This review article focused on the ability of these scores to predict AF prevention by statins.

The effect of atorvastatin and simvastatin on vitamin D, oxidative stress and inflammatory marker concentrations in patients with type 2 diabetes: a crossover study

The pleiotropic effect of statins may be mediated in part through raising 25 hydroxy vitamin D (25OHD) concentrations. It has also been shown that an increase in oxidative stress and inflammatory markers are a feature of the patients with type 2 diabetes (T2DM). A cross-over study of 26 patients with T2DM taking either simvastatin 40 mg or atorvastatin 10 mg was undertaken. After 3 months on one statin, lipids, C-reactive protein (hsCRP), 25OHD and malondialdehyde (MDA) were measured repeatedly. The same procedure was then followed taking the other statin. Despite similar lipid-lowering, the mean 25OHD was higher on atorvastatin compared with simvastatin and the mean MDA and hsCRP levels lower, irrespective of which statin the patients were taking before crossover. The changes in 25OHD predicted changes in CRP and MDA levels. Thus, compared with simvastatin, atorvastatin shows apparently beneficial pleiotropic effects with respect to 25OHD concentrations as well as markers of oxidative stress and inflammation in patients with T2DM.

Pharmacologic strategies to target oxidative stress in heart failure

Reactive oxygen species (ROS), which are involved in normal physiological functions at low concentrations, can have deleterious effects when produced in excess. Over time, ROS may result in a pathological state of imbalance known as oxidative stress. Oxidative stress has long been implicated in many diseases, and is consistently associated with poor outcomes in heart failure. Most therapies that are currently being used may provide some reduction in oxidative stress, but there is no consensus on the clinical outcomes of various antioxidants. Currently, there are no antioxidant therapies that are being used routinely to specifically target oxidative stress in patients with heart failure. This article reviews the current understanding of ROS generation, and the potential for novel pharmacologic strategies to target oxidative stress in heart failure.

Protective effects of l-carnitine and piracetam against mitochondrial permeability transition and PC3 cell necrosis induced by simvastatin

Mitochondrial oxidative stress followed by membrane permeability transition (MPT) has been considered as a possible mechanism for statins cytotoxicity. Statins use has been associated with reduced risk of cancer incidence, especially prostate cancer. Here we investigated the pathways leading to simvastatin-induced prostate cancer cell death as well as the mechanisms of cell death protection by l-carnitine or piracetam. These compounds are known to prevent and/or protect against cell death mediated by oxidative mitochondrial damage induced by a variety of conditions, either in vivo or in vitro. The results provide evidence that simvastatin induced MPT and cell necrosis were sensitive to either l-carnitine or piracetam in a dose-dependent fashion and mediated by additive mechanisms. When combined, l-carnitine and piracetam acted at concentrations significantly lower than they act individually. These results shed new light into both the cytotoxic mechanisms of statins and the mechanisms underlying the protection against MPT and cell death by the compounds l-carnitine and piracetam.

Atorvastatin improves erectile dysfunction in patients initially irresponsive to Sildenafil by the activation of endothelial nitric oxide synthase

This study aimed at comparing the effects of atorvastatin and vitamin E on erectile dysfunction in patients initially irresponsive to sildenafil, with investigation into the underlying possible mechanisms. Sixty patients were randomly divided into three groups: the atorvastatin group received 80 mg daily, the vitamin E group received 400 IU daily and the control group received placebo capsules. Patients were examined both before and after 6 weeks of treatment for biochemical tests; Superoxide dismutase (SOD), glutathione peroxidase (GPO), C-reactive protein (CRP), interleukin-6 (IL-6), nitric oxide (NO) and endothelial nitric oxide synthase (eNOS) and for erectile function tests; International index of erectile function (IIEF-5) scores and Rigiscan. Both atorvastatin and vitamin E showed a statistically significant GPO increase (P<0.05) and a statistically significant IL-6 decrease (P<0.05). Only atorvastatin showed a statistically significant increase in NO (15.19%, P<0.05), eNOS (20.58%, P<0.01), IIEF-5 score (53.1%, P<0.001) and Rigiscan rigidity parameters (P<0.01), in addition to a statistically significant decrease in CRP (57.9%, P<0.01). However, SOD showed a statistically significant increase only after vitamin E intake (23.1%, P<0.05). Both atorvatstain and vitamin E had antioxidant and anti-inflammatory activities. Although activating eNOS by atorvastatin was the real difference, and expected to be the main mechanism for NO increase and for improving erectile dysfunction. Atorvastatin, but not vitamin E, is a promising drug for sildenafil nonresponders.

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.

Atorvastatin reduces malondialdehyde concentrations in patients with polycystic ovary syndrome

BACKGROUND

It has been shown that there is an increase in oxidative stress in polycystic ovary syndrome (PCOS). Statins are considered to have a pleiotropic effect other than their lipid-lowering effect. These effects may be mediated in part by reducing oxidative stress.

METHODS

This randomized, double-blind, placebo-controlled study was conducted to assess the effect of atorvastatin on serum malondialdehyde (MDA) concentrations as a marker of oxidative stress in patients with PCOS. Forty medication-naïve patients with PCOS were randomized to either atorvastatin 20 mg daily or placebo for 3 months. A 3-month extension study for both groups of patients was undertaken with metformin 1500 mg daily after completing initial 3 months of atorvastatin or placebo.

RESULTS

There was a significant decrease of MDA concentrations with atorvastatin [mean (sem)] [0.29 (0.04) vs. 0.25 (0.02) μmol/liter; P < 0.01] compared with placebo [0.28 (0.02) vs. 0.29 (0.12) μmol/liter; P = 0.52]. Three months treatment with metformin resulted in further reduction of MDA levels with atorvastatin compared with baseline [0.25 (0.02) baseline vs. 0.23 (0.03) μmol/liter for atorvastatin treated; P = 0.02]. There was also a significant correlation between the reduction in MDA with a reduction in high-sensitivity C-reactive protein (r = 0.71, P < 0.01), an increase in 25-hydroxyvitamin D (25OHD; r = -0.68, P = 0.02), and a reduction in testosterone levels (r = 0.63, P = 0.01). Multiple linear regression analysis revealed Δ25OHD, ΔC-reactive protein, and Δtestosterone were independent predictors of changes in MDA after atorvastatin treatment. No correlation was observed between the reductions in serum MDA concentrations with changes in the lipid parameters.

CONCLUSIONS

Twelve weeks of atorvastatin led to a significant reduction in oxidative stress as determined by MDA concentrations among patients with polycystic ovary syndrome that was independently predicted by changes in testosterone, 25OHD, and high-sensitivity C-reactive protein.

Susceptibility to simvastatin-induced toxicity is partly determined by mitochondrial respiration and phosphorylation state of Akt

Statins are widely used to prevent cardiovascular diseases. They are well-tolerated, with side-effects mainly seen in skeletal muscle. How these side-effects are caused is unknown. We compared isolated primary mouse skeletal muscle myocytes, C2C12 myotubes and liver HepG2 cells to detect differences that could uncover why statins are toxic in skeletal muscle but less so in the liver. 10μM simvastatin caused a decrease in mitochondrial respiration in the primary mouse myocytes and C2C12 myotubes, but had no effect in the HepG2 cells. Mitochondrial integrity is maintained by multiple signaling pathways. One of these pathways, Igf-1/Akt signaling, is also heavily implicated in causing statin-induced toxicity by upregulating atrogin-1. We found that phosphorylated Akt was reduced in C2C12 myotubes but not in HepG2 cells. HepG2 mitochondrial respiration became susceptible to simvastatin-treatment after Akt inhibition, and mitochondrial respiration was rescued in Igf-1-treated C2C12 myotubes. These results suggest that disruption of Igf-1/Akt signaling is a causative factor in simvastatin-induced mitochondrial dysfunction in C2C12 myotubes, whereas HepG2 cells are protected by maintaining Igf-1/Akt signaling. We conclude that phosphorylation of Akt is a key indicator of susceptibility to statin-induced toxicity. How statins can disrupt Igf-1/Akt signaling is unknown. Statins reduce geranylgeranylation of small GTPases, such as Rap1. Previous studies implicate Rap1 as a link between cAMP/Epac and Igf-1/Akt signaling. Transient transfection of constitutively active Rap1 into C2C12 myotubes led to a partial rescue of simvastatin-induced inhibition of mitochondrial respiration, providing a novel link between signaling and respiration.

Long-term high-dose atorvastatin decreases brain oxidative and nitrosative stress in a preclinical model of Alzheimer disease: a novel mechanism of action

Alzheimer disease (AD) is an age-related neurodegenerative disorder characterized by progressive memory loss, inability to perform the activities of daily living and personality changes. Unfortunately, drugs effective for this disease are limited to acetylcholinesterase inhibitors that do not impact disease pathogenesis. Statins, which belong to the class of cholesterol-reducing drugs, were proposed as novel agents useful in AD therapy, but the mechanism underlying their neuroprotective effect is still unknown. In this study, we show that atorvastatin may have antioxidant effects, in aged beagles, that represent a natural higher mammalian model of AD. Atorvastatin (80 mg/day for 14.5 months) significantly reduced lipoperoxidation, protein oxidation and nitration, and increased GSH levels in parietal cortex of aged beagles. This effect was specific for brain because it was not paralleled by a concomitant reduction in all these parameters in serum. In addition, atorvastatin slightly reduced the formation of cholesterol oxidation products in cortex but increased the 7-ketocholesterol/total cholesterol ratio in serum. We also found that increased oxidative damage in the parietal cortex was associated with poorer learning (visual discrimination task). Thus, a novel pharmacological effect of atorvastatin mediated by reducing oxidative damage may be one mechanism underlying benefits of this drug in AD.