Statins in neurological disorders: An overview and update

Mechanisms of inflammation after ischemic stroke in brain-peripheral crosstalk

Stroke is a devastating disease with high morbidity, disability, and mortality, among which ischemic stroke is more common. However, there is still a lack of effective methods to improve the prognosis and reduce the incidence of its complications. At present, there is evidence that peripheral organs are involved in the inflammatory response after stroke. Moreover, the interaction between central and peripheral inflammation includes the activation of resident and peripheral immune cells, as well as the activation of inflammation-related signaling pathways, which all play an important role in the pathophysiology of stroke. In this review, we discuss the mechanisms of inflammatory response after ischemic stroke, as well as the interactions through circulatory pathways between peripheral organs (such as the gut, heart, lung and spleen) and the brain to mediate and regulate inflammation after ischemic stroke. We also propose the potential role of meningeal lymphatic vessels (MLVs)-cervical lymph nodes (CLNs) as a brain-peripheral crosstalk lymphatic pathway in ischemic stroke. In addition, we also summarize the mechanisms of anti-inflammatory drugs in the treatment of ischemic stroke.

Updates on brain regions and neuronal circuits of movement disorders in Parkinson's disease

Parkinson's disease (PD) is a progressive neurodegenerative disease with a global burden that affects more often in the elderly. The basal ganglia (BG) is believed to account for movement disorders in PD. More recently, new findings in the original regions in BG involved in motor control, as well as the new circuits or new nucleuses previously not specifically considered were explored. In the present review, we provide up-to-date information related to movement disorders and modulations in PD, especially from the perspectives of brain regions and neuronal circuits. Meanwhile, there are updates in deep brain stimulation (DBS) and other factors for the motor improvement in PD. Comprehensive understandings of brain regions and neuronal circuits involved in motor control could benefit the development of novel therapeutical strategies in PD.

Low-dose atorvastatin protects skeletal muscle mitochondria in high-fat diet-fed mice with mitochondrial autophagy inhibition and fusion enhancement

Despite the great clinical benefits of statins in cardiovascular diseases, their widespread use may lead to adverse muscle reactions associated with mitochondrial dysfunction. Some studies have demonstrated that statins provide substantial improvement to skeletal muscle health in mice. Our previous study found that oral treatment with atorvastatin (Ator, 3 mg/kg) protected myocardial mitochondria in high-fat diet (HFD)-fed mice. Therefore, this study aimed to explore the influence of low-dose Ator (3 mg/kg) on mitochondria in skeletal muscle under cholesterol overload. Male C57BL/6J mice were fed a HFD for 18 weeks and orally administered Ator (3 mg/kg) during the last 12 weeks. Ator treatment had no effects on elevated serum cholesterol and glucose levels in HFD-fed mice. Serum creatine kinase levels and the cross-sectional area of muscle cells were not affected by HFD feeding or Ator treatment. Increased expression of PINK1-LC3 II (activated mitophagy), MFN2 (fusion), and PGC-1α (biogenesis) proteins was induced in the skeletal muscles of HFD-fed mice. Treatment with Ator inhibited PINK1 and LC3 II protein expression, but further promoted MFN1, MFN2, and OPA1 expression. The impairments in mitochondrial quality and morphology in HFD-fed mice were attenuated by treatment with Ator. Furthermore, Ator treatment enhanced glucose oxidation capacity and restored ATP production in the skeletal muscles of HFD-fed mice. The study reveals that low-dose Ator has a protective effect on muscle mitochondria in mice, likely through inhibiting mitophagy and enhancing mitochondrial fusion. This suggests that skeletal muscle mitochondria may be one of low-dose Ator-mediated protective targets.

Association between the Use of Statins and Brain Tumors

This study aimed to investigate the effects of statin use on the incidence of brain tumors. The Korean National Health Insurance Service-National Sample Cohort from 2005 to 2019 was used. The 1893 patients who were diagnosed with brain tumors were matched with 7572 control patients for demographic variables. The history of dyslipidemia was collected, and their history of prescription of statins before diagnosis of brain tumor was examined. The participants without dyslipidemia were set as a reference population. Then, the odds for brain tumors were analyzed in dyslipidemia patients without statin use, dyslipidemia patients who were prescribed statins for less than 365 days, and dyslipidemia patients who were prescribed statins for 365 days or more. Propensity score overlap weighted multivariable logistic regression analysis was used and adjusted for demographics and comorbidities. Secondary analyses were conducted according to types of statins, malignancy of brain tumors, and histories of demographics or comorbidities. A total of 11.78% of brain tumor patients and 10.95% of control participants had histories of statin use for 365 days or more. Dyslipidemia patients with 365 days or more duration of statin use demonstrated 1.22 times higher odds for brain tumors than normal participants (95% confidence intervals [CI] = 1.06-1.14, p = 0.007). Dyslipidemia patients with less than 365 days of statin use had higher odds of brain tumors than other groups (odds ratio = 1.60, 95% CI = 1.36-1.87, p < 0.001). The higher odds for brain tumors in short-term statin users (<365 days) than in long-term statin users (≥365 days) were consistent in secondary analyses according to types of statins, malignancy of brain tumors, and histories of demographics or comorbidities. Long-term statin use in dyslipidemia patients was related to a lower risk of brain tumors than short-term statin use in patients with dyslipidemia.

DHCR24 reverses Alzheimer's disease-related pathology and cognitive impairment via increasing hippocampal cholesterol levels in 5xFAD mice

Accumulating evidences reveal that cellular cholesterol deficiency could trigger the onset of Alzheimer's disease (AD). As a key regulator, 24-dehydrocholesterol reductase (DHCR24) controls cellular cholesterol homeostasis, which was found to be downregulated in AD vulnerable regions and involved in AD-related pathological activities. However, DHCR24 as a potential therapeutic target for AD remains to be identified. In present study, we demonstrated the role of DHCR24 in AD by employing delivery of adeno-associated virus carrying DHCR24 gene into the hippocampus of 5xFAD mice. Here, we found that 5xFAD mice had lower levels of cholesterol and DHCR24 expression, and the cholesterol loss was alleviated by DHCR24 overexpression. Surprisingly, the cognitive impairment of 5xFAD mice was significantly reversed after DHCR24-based gene therapy. Moreover, we revealed that DHCR24 knock-in successfully prevented or reversed AD-related pathology in 5xFAD mice, including amyloid-β deposition, synaptic injuries, autophagy, reactive astrocytosis, microglial phagocytosis and apoptosis. In conclusion, our results firstly demonstrated that the potential value of DHCR24-mediated regulation of cellular cholesterol level as a promising treatment for AD.

Wound Healing Efficacy of Rosuvastatin Transethosomal Gel, I Optimal Optimization, Histological and In Vivo Evaluation

This study aimed to make a formulation and statistical optimization of transethosomal formulations of rosuvastatin (ROS) to enhance its topical wound healing efficiency. Design-Expert^® software was used to employ I optimal design. The formulation variables in the study were surfactant concentration (%w/v), ethanol concentration (%w/v) and surfactant type (span 60 or tween 80), while the dependent responses were entrapment efficiency percent (EE%), vesicle size (VS) and zeta potential (ZP). The numerical optimization process employed by the design expert software resulted in an optimum formula composed of 0.819439 (%w/v) span 60, 40 (%w/v) ethanol and 100 mg lecithin with a desirability of 0.745. It showed a predicted EE% value of 66.5517 vs. 277.703 nm and a ZP of -33. When it was prepared and validated, it showed less than a 5% deviation from the predicted values. The optimum formula was subjected to further characterizations, such as DSC, XRD, TEM, in vitro release, the effect of aging and wound healing efficiency. The DSC thermogram made a confirmation of the compatibility of ROS with the ingredients used in the formulation. XRD showed the encapsulation of ROS in the transethosomal vesicles. The TEM image pointed out the spherical nature of the nanovesicles with the absence of aggregation. Additionally, the optimum formula revealed an enhancement of drug release in comparison with the drug suspension. It also showed good stability for one month. Furthermore, it revealed good wound healing efficiency when compared with the standard silver sulphadiazine (1% w/w) ointment or the drug-loaded gel, which could be related to the enhanced penetration of the nanosized vesicles of TESMs into the skin, which enhances the wound healing process. So, it could be regarded as a promising carrier of ROS for the treatment of chronic wounds.

Perspectives on the Molecular Mediators of Oxidative Stress and Antioxidant Strategies in the Context of Neuroprotection and Neurolongevity: An Extensive Review

Molecules with at least one unpaired electron in their outermost shell are known as free radicals. Free radical molecules are produced either within our bodies or by external sources such as ozone, cigarette smoking, X-rays, industrial chemicals, and air pollution. Disruption of normal cellular homeostasis by redox signaling may result in cardiovascular, neurodegenerative diseases and cancer. Although ROS (reactive oxygen species) are formed in the GI tract, little is known about how they contribute to pathophysiology and disease etiology. When reactive oxygen species and antioxidants are in imbalance in our bodies, they can cause cell structure damage, neurodegenerative diseases, diabetes, hypercholesterolemia, atherosclerosis, cancer, cardiovascular diseases, metabolic disorders, and other obesity-related disorders, as well as protein misfolding, mitochondrial dysfunction, glial cell activation, and subsequent cellular apoptosis. Neuron cells are gradually destroyed in neurodegenerative diseases. The production of inappropriately aggregated proteins is strongly linked to oxidative stress. This review's goal is to provide as much information as possible about the numerous neurodegenerative illnesses linked to oxidative stress. The possibilities of multimodal and neuroprotective therapy in human illness, using already accessible medications and demonstrating neuroprotective promise in animal models, are highlighted. Neuroprotection and neurolongevity may improve from the use of bioactive substances from medicinal herbs like Allium stadium, Celastrus paniculatus, and Centella asiatica. Many neuroprotective drugs' possible role has been addressed. Preventing neuroinflammation has been demonstrated in several animal models.

The impact of statins on wound healing: an ally in treating the highly comorbid patient

OBJECTIVE

To identify the impact that HMG-CoA reductase inhibitors (statins) use has on wound healing outcomes in patients with comorbidities.

METHOD

A retrospective chart review evaluating all new patients presenting to our tertiary wound care centre in 2013 with lower extremity wounds. Patients were divided into two groups depending on whether they took statins or not. Data on wound healing outcomes and wound/patient characteristics were collected. Primary outcomes included healing rate and progression to complete wound healing. Patients were excluded if they had incomplete data or were lost to follow-up before healing status could be confirmed.

RESULTS

A total of 194 patients met the inclusion criteria and were allocated to either the statin group (n=89) or to the non-statin group (n=105). Median initial wound size was 0.6cm³ (Interquartile range (IQR): 0.15-2.4) (p=0.684). In the statin group, 54 (60.6%) patients progressed to complete wound healing compared with 47 (44.7%) in the non-statin group (p=0.027). Median rate of wound healing was 6.7×10^-3cm³/day (IQR: 1.5×10^-3-2.6×10^-2) compared with 3.8×10^-3cm³/day (IQR: 1.7×10^-3-1.3×10^-2) in the non-statin group (p=0.773). Increased age and a higher number of comorbidities were reported in the statin group (p<0.001), respectively). A total of seven patients required amputation: five patients in the statin group and two patients in the non-statin group (p=0.250).

CONCLUSION

This study revealed increased progression to wound healing in patients who were taking statins. The influence of statins on wound healing is promising, but future trials are needed to justify use of this medication class independent of cardiovascular benefit and exclusively for wound healing.

Statin use and pneumonia risk in Parkinson's disease

INTRODUCTION

Previous studies reported that statin use was related to a lower risk of pneumonia in the general population. This study investigated the association between statin use and pneumonia risk in patients with Parkinson's disease (PD).

METHODS

Patients that had been newly diagnosed with PD between 2004 and 2006 in the 2002-2017 National Health Insurance Service database in South Korea were identified. PD patients who had received one or more statin prescriptions, and experienced pneumonia during the observation period were included in the self-controlled case series (SCCS) analysis. Patients who had no previous statin prescription record were included in the Cox proportional hazard model with a time-varying covariate (statin use). The risk of pneumonia in PD patients with statin use was estimated after adjusting potential confounders.

RESULTS

Of the 10,159 patients with PD, 337 individuals were eligible for the SCCS analysis. The median duration of statin exposure was 2.63 years (IQR, 0.83-5.83). The incidence of pneumonia was reduced in the statin-exposed period compared to the unexposed period (incidence rate ratio, 0.88; 95% CI, 0.86-0.91). A total of 8,022 patients were included in the Cox proportional hazard model. Statin use was related to a significantly reduced pneumonia risk (adjusted hazard ratio, 0.69; 95% CI, 0.62-0.78).

CONCLUSIONS

Statin use was associated with a lower risk of pneumonia in PD patients. Statins might affect pneumonia occurrence by lowering cholesterol levels or slowing the progression of PD as neuroprotective agents. Further clinical studies are needed to delineate our findings with the underlying biological mechanisms.

Effects of statins on dopamine loss and prognosis in Parkinson's disease

Statins are more widely used not only for the primary and secondary prevention of cardiovascular disease by blocking cholesterol biosynthesis but also for the potential neuroprotective agents during neurological disorders due to their pleiotropic effects. In this study, we investigate whether the prior use of statins affect baseline nigrostriatal dopamine loss at the time of diagnosis and longitudinal motor and cognitive outcomes in patients with Parkinson's disease. Five hundred drug-naïve patients with Parkinson's disease who underwent dopamine transporter imaging were classified into two groups according to the prior use of statins: patients with and without statin use. Multivariate linear regression was used to determine inter-group differences in dopamine transporter availability. We evaluated the longitudinal changes in levodopa-equivalent dose and dementia conversion between the groups using a linear mixed model and survival analysis, respectively. In addition, mediation analysis was applied to examine the effect of total cholesterol. Patients with Parkinson's disease treated with statin had a lower baseline dopamine transporter availability in the anterior (2.13 ± 0.55 vs. 2.37 ± 0.67; p = 0.002), posterior (1.31 ± 0.43 vs. 1.49 ± 0.54; p = 0.003), and ventral putamina (1.40 ± 0.39 vs. 1.56 ± 0.47; p = 0.002) than that in matched patients with Parkinson's disease without statin. After adjusting for age at symptom onset, sex, disease duration and vascular risk factors, linear regression models showed that a prior treatment of statin remained significantly and independently associated with more severely decreased dopamine transporter availability in the anterior putamen (Beta = -0.140, p = 0.004), posterior putamen (Beta = -0.162, p = 0.001), and ventral putamen (Beta = -0.140, p = 0.004). A linear mixed model revealed that patients with Parkinson's disease being treated with statin had a faster longitudinal increase in levodopa-equivalent dose than those without statin. A survival analysis showed that the rate of dementia conversion was significantly higher in patients with Parkinson's disease with statin (hazard ratio, 2.019; 95% CI, 1.108 - 3.678; P = 0.022) than those without statin. Mediation analyses revealed that the effect of statin treatment on baseline dopamine transporter availability and longitudinal outcome was not mediated by total cholesterol levels. This study suggests that statin use may have a detrimental effect on baseline nigrostriatal dopamine degeneration and long-term outcomes in patients with Parkinson's disease.

Statins and risk of amyotrophic lateral sclerosis: a systematic review and meta-analysis

Amyotrophic lateral sclerosis (ALS) is a paralytic, heterogeneous and progressive disease characterized by the degeneration of both upper and lower motor neurons. Several studies about the effects of statins drug on the risk of ALS showed contradictory results and evidence for this is inconclusive. So we aimed to perform a meta-analysis on previous studies to clarify the association between statin use and risk of ALS. The databases including PubMed, Scopus, and Web of science were searched in February 2021 for studies that reported the association between statin use and risk of ALS. The eligible studies had to provide a report on the effect of statin and the incidence of ALS while comparing it to the control group. Articles that had low statin exposure time, the absence of a control group and an unknown number of ALS patients were excluded. The rate ratio and 95% confidence interval (CI) were used for association measures in case-control and cohort studies. After full-text and abstract review, data from 8 studies with a total of 547,622 participants and 13,890 cases of ALS were entered in the present meta-analysis. We combined eight studies using a random-effect model and the RR for statin users among groups was 0.98 (95% CI 0.80-1.20) which indicates no association between statin and incidence of ALS. Also high heterogeneity was detected across the studies (Q value = 26.62, P = .00; I² = 72.71%). In our meta-analysis study, we found no association between statin use and an increase in ALS incidence. This result is in line with some previous studies and provides strong evidence that denies the possible association between statin uptake and disease induction.

Pitavastatin Ameliorates Lipopolysaccharide-Induced Blood-Brain Barrier Dysfunction

Statins have neuroprotective effects on neurological diseases, including a pleiotropic effect possibly related to blood–brain barrier (BBB) function. In this study, we investigated the effects of pitavastatin (PTV) on lipopolysaccharide (LPS)-induced BBB dysfunction in an in vitro BBB model comprising cocultured primary mouse brain endothelial cells, pericytes, and astrocytes. LPS (1 ng/mL, 24 h) increased the permeability and lowered the transendothelial electrical resistance of the BBB, and the co-administration of PTV prevented these effects. LPS increased the release of interleukin-6, granulocyte colony-stimulating factor, keratinocyte-derived chemokine, monocyte chemotactic protein-1, and regulated on activation, normal T-cell expressed and secreted from the BBB model. PTV inhibited the LPS-induced release of these cytokines. These results suggest that PTV can ameliorate LPS-induced BBB dysfunction, and these effects might be mediated through the inhibition of LPS-induced cytokine production. Clinically, therapeutic approaches using statins combined with novel strategies need to be designed. Our present finding sheds light on the pharmacological significance of statins in the treatment of central nervous system diseases.

Role of inflammatory, oxidative, and ER stress signaling in the neuroprotective effect of atorvastatin against doxorubicin-induced cognitive impairment in rats

Doxorubicin (DOX) is a potent chemotherapeutic agent widely used for the treatment of several malignancies. Despite its effectiveness, DOX has been implicated in induced neurotoxicity manifested as cognitive dysfunction with varying degrees, commonly referred to as chemobrain. DOX-induced chemobrain is presumed to be due to cytokine-induced inflammatory, oxidative, and apoptotic responses damaging the brain. Atorvastatin (ATV), 3-hydroxy 3-methylglutaryl co-enzyme A (HMG Co-A) reductase inhibitor, is a cholesterol-lowering statin possessing beneficial pleiotropic effects, including anti-inflammatory, antioxidant, and anti-apoptotic properties. Therefore, this study aims to investigate the potential neuroprotective effects of ATV against DOX-induced cognitive impairment studying the possible involvement of heme oxygenase-1 (HO-1) and endoplasmic reticulum (ER) stress biomarkers. Rats were treated with DOX (2 mg/kg/week), i.p. for 4 weeks. Oral treatment with ATV (10 mg/kg) ameliorated DOX-induced behavioral alterations, protected brain histological features, and attenuated DOX-induced inflammatory, oxidative, and apoptotic biomarkers. In addition, ATV upregulated the protective HO-1 expression levels and downregulated the DOX-induced apoptotic ER stress biomarkers. In conclusion, ATV (10 mg/kg) exhibited neuroprotective properties against DOX-induced cognitive impairment which could possibly be attributed to their anti-inflammatory, antioxidant, and anti-apoptotic effects in the brain.

Involvement of agmatine in antidepressant-like effect of HMG-CoA reductase inhibitors in mice

3-Hydroxy-3-methyl-glutaryl-co-enzyme-A (HMG-CoA) reductase inhibitors (statins) are popularly used for the treatment of obesity and hypercholesterolemia with established safety profile. Statins exhibits a wide range of neurobehavioral effects in addition to their peripheral actions, and may be beneficial in treatment of psychiatric conditions. Present study investigated the role of agmatine and imidazoline receptors in antidepressant-like effect of statins in mouse forced swimming test (FST). The antidepressant-like effect of atorvastatin (5 mg/kg, p.o.) and simvastatin (10 mg/kg, p.o.) was potentiated by pretreatment with agmatine (5 mg/kg, i.p.) as well as the drugs known to increase endogenous agmatine levels in brain viz., L-arginine (40 μg/mouse, i.c.v.), an agmatine biosynthetic precursor; arcaine (50 μg/mouse, i.c.v), agmatinase inhibitor; and aminoguanidine (6.5 μg/mouse, i.c.v.), a diamine oxidase inhibitor. Further, both the statins increased agmatine levels within hippocampus and prefrontal cortex. Conversely, prior administration of I₁ receptor antagonist, efaroxan (1 mg/kg, i.p.) and I₂ receptor antagonist, idazoxan (0.25 mg/kg, i.p.) blocked the antidepressant-like effect of statins and their synergistic combination with agmatine. These results demonstrate the involvement of agmatine and imidazoline receptors in antidepressant-like effect of statins and suggest as a potential therapeutic target for the treatment of depressive disorders.

24S-hydroxycholesterol: Cellular effects and variations in brain diseases

The adult brain exhibits a characteristic cholesterol homeostasis, with low synthesis rate and active catabolism. Brain cholesterol turnover is possible thanks to the action of the enzyme cytochrome P450 46A1 (CYP46A1) or 24-cholesterol hydroxylase, that transforms cholesterol into 24S-hydroxycholesterol (24S-HC). But before crossing the blood-brain barrier (BBB), this oxysterol, that is the most abundant in the brain, can act locally, affecting the functioning of neurons, astrocytes, oligodendrocytes, and vascular cells. The first part of this review addresses different aspects of 24S-HC production and elimination from the brain. The second part concentrates in the effects of 24S-HC at the cellular level, describing how this oxysterol affects cell viability, amyloid β production, neurotransmission, and transcriptional activity. Finally, the role of 24S-HC in Alzheimer, Huntington and Parkinson diseases, multiple sclerosis and amyotrophic lateral sclerosis, as well as the possibility of using this oxysterol as predictive and/or evolution biomarker in different brain disorders is discussed.

Environmental enrichment-inspired pharmacological tools for the treatment of addiction

Environmental enrichment (EE) has been shown to produce powerful beneficial effects in animal models of addiction. In particular, the ability of EE to promote abstinence and prevent relapse may allow for the identification of brain mechanisms responsible for the recovery from addiction. Indeed, the effects of EE on specific brain mechanisms could be mimicked by old or new molecules, which may become novel medications, called enviromimetics. Here, we review the best known enviromimetics for the treatment of addiction and suggest that, whereas these compounds may be relatively ineffective by themselves, they may be useful complements for existing therapeutic approaches to manage addiction which includes behavioural, environmental and pharmacological interventions.

Statins combined with niacin reduce the risk of peripheral neuropathy

Statins are a class of lipid-lowering medications that reduce illness and mortality in those who are at a high risk of developing cardiovascular disease. They are the most common cholesterol-lowering drugs. A case control study published in 2002 indicated that statins may increase the risk of peripheral neuropathy. Statin users were 14-fold more likely to develop peripheral neuropathy than non-users, although the overall risk of developing neuropathy was minimal. However, a number of other studies have produced conflicting results regarding neuropathy and statins. Statins are frequently combined with niacin (vitamin B3). Due to its beneficial effects on lipid profiles, niacin has been prescribed for the prevention of heart disease for >40 years. Among the B vitamins, niacin has long been recognized as a key mediator of neuronal development and survival, and may be of value for the treatment of neuropathy. The present study aimed to assess whether the combination of niacin and statin may reduce the risk of peripheral neuropathy attributed to statins. For this purpose, data from MedWatch, the Food and Drug Administration (FDA) Safety Information and Adverse Event Reporting Program were analyzed. The online tool OpenVigil 2.1 was used to query the databases. The results revealed that the majority of statins alone were related to neuropathy. Pitavastatin was the only exception. The association with neuropathy was most pronounced in the lipophilic statins: Atorvastatin and fluvastatin. The association was weaker for other lipophilic statins, such as lovastatin and simvastatin. Two hydrophilic statins, rosuvastatin and pravastatin, exhibited a similarly weaker association with neuropathy, while no reports of any association of pitavastatin with neuropathy were found. Statins + niacin were unrelated to neuropathy. On the whole, the findings of the present study demonstrate that the controversial association of statins with neuropathy may be due to the fact that previous studies have not included the use of niacin and the potential neuroprotective effects of niacin. Multiple reports have stated that niacin is no longer beneficial for the management of hyperlipidemia and should be abandoned. However, given the apparent ability of niacin to reduce the risk of neuropathy, perhaps niacin should not be discarded before further studies are performed to provide more in depth information.

Lovastatin producing by wild strain of Aspergillus terreus isolated from Brazil

Lovastatin is a drug in the statin class which acts as a natural inhibitor of 3-hydroxy-3-methylglutaryl, a coenzyme reductase reported as being a potential therapeutic agent for several diseases: Alzheimer's, multiple sclerosis, osteoporosis and due to its anti-cancer properties. Aspergillus terreus is known for producing a cholesterol reducing drug. This study sets out to evaluate the production of lovastatin by Brazilian wild strains of A. terreus isolated from a biological sample and natural sources. Carbon and nitrogen sources and the best physicochemical conditions using factorial design were also evaluated. The 37 fungal were grown to produce lovastatin by submerged fermentation. A. terreus URM5579 strain was the best lovastatin producer with a level of 13.96 mg/L. Soluble starch and soybean flour were found to be the most suitable substrates for producing lovastatin (41.23 mg/L) and biomass (6.1 mg/mL). The most favorable production conditions were found in run 16 with 60 g/L soluble starch, 15 g/L soybean flour, pH 7.5, 200 rpm and maintaining the solution at 32 °C for 7 days, which led to producing 100.86 mg/L of lovastatin and 17.68 mg/mL of biomass. Using natural strains and economically viable substrates helps to optimize the production of lovastatin and promote its use.

Simvastatin, edaravone and dexamethasone protect against kainate-induced brain endothelial cell damage

BACKGROUND

Excitotoxicity is a central pathological pathway in many neurological diseases with blood-brain barrier (BBB) dysfunction. Kainate, an exogenous excitotoxin, induces epilepsy and BBB damage in animal models, but the direct effect of kainate on brain endothelial cells has not been studied in detail. Our aim was to examine the direct effects of kainate on cultured cells of the BBB and to test three anti-inflammatory and antioxidant drugs used in clinical practice, simvastatin, edaravone and dexamethasone, to protect against kainate-induced changes.

METHODS

Primary rat brain endothelial cell, pericyte and astroglia cultures were used to study cell viability by impedance measurement. BBB permeability was measured on a model made from the co-culture of the three cell types. The production of nitrogen monoxide and reactive oxygen species was followed by fluorescent probes. The mRNA expression of kainate receptors and nitric oxide synthases were studied by PCR.

RESULTS

Kainate damaged brain endothelial cells and made the immunostaining of junctional proteins claudin-5 and zonula occludens-1 discontinuous at the cell border indicating the opening of the barrier. The permeability of the BBB model for marker molecules fluorescein and albumin and the production of nitric oxide in brain endothelial cells were increased by kainate. Simvastatin, edaravone and dexamethasone protected against the reduced cell viability, increased permeability and the morphological changes in cellular junctions caused by kainate. Dexamethasone attenuated the elevated nitric oxide production and decreased the inducible nitric oxide synthase (NOS2/iNOS) mRNA expression increased by kainate treatment.

CONCLUSION

Kainate directly damaged cultured brain endothelial cells. Simvastatin, edaravone and dexamethasone protected the BBB model against kainate-induced changes. Our results confirmed the potential clinical usefulness of these drugs to attenuate BBB damage.

Nutraceuticals and physical activity: Their role on oxysterols-mediated neurodegeneration

Over the past few years, the contribution of oxysterols to the onset and development of some of the major neurodegenerative diseases (such as Alzheimer's and Parkinson's diseases) has been scientifically asserted, being mainly related to altered brain cholesterol homeostasis. To counteract oxysterol induced inflammation at neuronal level, one possible intervention approach is the administration of some nutrients and/or plant secondary metabolites. On the other hand, the pleiotropic beneficial effects of physical activity seem to play an important role on prevention and counteraction of neurodegenerative diseases, through the modulation of oxysterol homeostasis and the prevention of demyelination. The present review provides a picture of the promising role of nutraceuticals and physical activity on oxysterol-mediated neurodegeneration, pointing out also the different in vitro and in vivo aspects that need to be further investigated for a better understanding of the association of these three counterparts and their overall effect on people at increased risk for neurodegenerative diseases.

Association between Statin Use and Sepsis Risk in Patients with Dementia: A Retrospective Cohort Study

This study investigated the association of statin use with sepsis risk in patients with dementia. This retrospective cohort study was conducted in Taiwan by using data from the National Health Insurance Research Database. We identified and enrolled 308 patients with newly diagnosed dementia who used statin after dementia diagnosis. These patients were individually propensity score matched (1:1) according to age, sex, hypertension, hyperlipidemia, diabetes, cerebrovascular disease, renal disease, liver disease, asthma, malignancy, parkinsonism, and dementia drugs used (donepezil, rivastigmine, galantamine, and memantine) with 251 controls (statin non-users). A Cox proportional hazard model was used to estimate the adjusted hazard ratio for sepsis in statin users and non-users. After adjustment for other confounding factors, the incidence of sepsis in statin users was 1.42-fold higher than that in non-users (95% confidence interval = 0.81–2.5). In conclusion, our analysis showed no positive association of sepsis with statin use in patients with dementia.

Statins and the Brain: More than Lipid Lowering Agents?

Background:

Statins represent a class of medications widely prescribed to efficiently treat dyslipidemia. These drugs inhibit 3-βhydroxy 3β-methylglutaryl Coenzyme A reductase (HMGR), the rate-limiting enzyme of mevalonate (MVA) pathway. Besides cholesterol, MVA pathway leads to the production of several other compounds, which are essen-tial in the regulation of a plethora of biological activities, including in the central nervous system. For these reasons, statins are able to induce pleiotropic actions, and acquire increased interest as potential and novel modulators in brain processes, es-pecially during pathological conditions.

Objective:

The purpose of this review is to summarize and examine the current knowledge about pharmacokinetic and phar-macodynamic properties of statins in the brain. In addition, effects of statin on brain diseases are discussed providing the most up-to-date information.

Methods:

Relevant scientific information was identified from PubMed database using the following keywords: statins and brain, central nervous system, neurological diseases, neurodegeneration, brain tumors, mood, stroke.

Results:

315 scientific articles were selected and analyzed for the writing of this review article. Several papers highlighted that statin treatment is effective in preventing or ameliorating the symptomatology of a number of brain pathologies. Howev-er, other studies failed to demonstrate a neuroprotective effect.

Conclusion:

Even though considerable research studies suggest pivotal functional outcomes induced by statin therapy, addi-tional investigation is required to better determine the pharmacological effectiveness of statins in the brain, and support their clinical use in the management of different neuropathologies.

Biocatalyzed Synthesis of Statins: A Sustainable Strategy for the Preparation of Valuable Drugs

Statins, inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, are the largest selling class of drugs prescribed for the pharmacological treatment of hypercholesterolemia and dyslipidaemia. Statins also possess other therapeutic effects, called pleiotropic, because the blockade of the conversion of HMG-CoA to (R)-mevalonate produces a concomitant inhibition of the biosynthesis of numerous isoprenoid metabolites (e.g., geranylgeranyl pyrophosphate (GGPP) or farnesyl pyrophosphate (FPP)). Thus, the prenylation of several cell signalling proteins (small GTPase family members: Ras, Rac, and Rho) is hampered, so that these molecular switches, controlling multiple pathways and cell functions (maintenance of cell shape, motility, factor secretion, differentiation, and proliferation) are regulated, leading to beneficial effects in cardiovascular health, regulation of the immune system, anti-inflammatory and immunosuppressive properties, prevention and treatment of sepsis, treatment of autoimmune diseases, osteoporosis, kidney and neurological disorders, or even in cancer therapy. Thus, there is a growing interest in developing more sustainable protocols for preparation of statins, and the introduction of biocatalyzed steps into the synthetic pathways is highly advantageous—synthetic routes are conducted under mild reaction conditions, at ambient temperature, and can use water as a reaction medium in many cases. Furthermore, their high selectivity avoids the need for functional group activation and protection/deprotection steps usually required in traditional organic synthesis. Therefore, biocatalysis provides shorter processes, produces less waste, and reduces manufacturing costs and environmental impact. In this review, we will comment on the pleiotropic effects of statins and will illustrate some biotransformations nowadays implemented for statin synthesis.

Unfolding the pleiotropic facades of rosuvastatin in therapeutic intervention of myriads of neurodegenerative disorders

Rosuvastatin, a 3-hydroxy-3-methylglutaryl-coenzyme (HMG-CoA) reductase inhibitor, and one of the most popular antihyperlipidemic medications have been found to possess pharmacodynamic activities much different from its usual indication. Recent research studies have revealed the efficacy of rosuvastatin in attenuating neuroinflammation, reducing the progression of Alzheimer's disease, providing protection against cerebral ischaemia and spinal cord injury as well as ameliorating epilepsy. Mechanisms behind the neuroprotective potential of rosuvastatin can be attributed to its pleiotropic effects, independent of its ability to inhibit HMG-CoA reductase. These processes include modulation of several cellular pathways, isoprenylation, effects on oxidative stress, nitrosative levels, inflammation, and immune response. This review aims to assimilate and summarize recent findings on the pharmacological actions of rosuvastatin in attenuating neurological disorders in order to guide future research in this space.

The Antineuroinflammatory Effect of Simvastatin on Lipopolysaccharide Activated Microglial Cells

Microglial cells, upon hyperactivation, produce proinflammatory cytokines and other oxidative stress mediators causing neuroinflammation, which is associated with the progress of many neurodegenerative diseases. Suppressing the microglial activation has hence been used as an approach for treating such diseases. In this study, the antineuroinflammatory effect of simvastatin was examined in lipopolysaccharide (LPS)-activated rat C6 glioma cells. The cell proliferation and cytotoxic effect of LPS and simvastatin on C6 glioma cells was evaluated by (MTT) assay. Neuroinflammation was induced in differentiated cell lines by treatment with 3.125 μg/mL of LPS for 12 h. Upon induction, the cell lines were treated with different concentrations (3.125, 6.25, 12.5, 25, 50, 100 μM) of simvastatin and incubated in a humidified CO₂ incubator for 24 to 48 h. The optimum concentrations of LPS and simvastatin were found to be 3.125 μg/mL and 25 μM, respectively, with a cell viability of more than 90% at 24 h postincubation. Furthermore, proinflammatory marker expression was analyzed by flow cytometry and showed a decrease in interferon-γ, interleukin 6, nuclear factor-κB p65, and tumor necrosis factor-α in simvastatin-treated and LPS-induced neuroinflammatory cells, and the mean fluorescent values were found to be 21.75 ± 0.76, 20.9 ± 1.90, 19.72 ± 1.29, and 16.82 ± 0.97, respectively, as compared to the untreated cells. Thus, we show that simvastatin has the potential to regulate the anti-inflammatory response in microglial cells upon LPS challenge. Hence, simvastatin can be employed as a potent anti-inflammatory drug against neuroinflammatory diseases and neurodegenerative disorders.

Does taking statins affect the pathological burden in autopsy-confirmed Alzheimer's dementia?

BACKGROUND

The efficacy of cholesterol lowering agents, specifically statins, in slowing the rate of decline of cognitive function in Alzheimer's disease (AD) patients is not yet fully understood. Our team's previously published paper showed that patients who used statins demonstrated no increase in cognitive decline in mild cognitive impairment when compared with nonusers. Further, AD patients on statins demonstrated a slight decreasing trend in cognitive decline. The purpose of this study is therefore to investigate the association between stain use in AD confirmed by clinical diagnosis and autopsy and the pathological burden (plaques, tangles, Braak stage). The hypothesis leading this investigation is that prolonged statin use associates with lower AD pathology at autopsy.

METHODS

We queried the National Alzheimer's Coordinating Center (NACC) database for autopsy-confirmed AD cases. Of the Uniform Data Set (UDS) participants who are deceased, 16,163 were diagnosed with dementia at their last UDS visit prior to death, and autopsy data are available for 3945 patients. These patients were then stratified into two groups based upon statin use. The two groups were then analyzed for their pathological AD burden, including total plaques, total tangles, age at death, age of onset, and Braak stage.

RESULTS

NACC data were available for 1816 subjects with clinically and pathologically confirmed AD; 1558 were not on statins and 258 were on statins. No significant differences in age at death, age at onset, Braak stages, mean total tau, and mean total amyloid were found between the two subject groups. When statin use was analyzed by apolipoprotein E (ApoE) genotype carrier statins, the presence of ApoE4 did not influence the effects (or lack thereof) of statin use.

CONCLUSIONS

Prolonged statin use in pathologically confirmed AD dementia does not appear to influence the amount of burden of plaques and tangles or Braak stage. These observations were not altered by the presence of absence of ApoE4.

The Therapeutic Potential of Metformin in Neurodegenerative Diseases

The search for treatments for neurodegenerative diseases is a major concern in light of today's aging population and an increasing burden on individuals, families, and society. Although great advances have been made in the last decades to understand the underlying genetic and biological cause of these diseases, only some symptomatic treatments are available. Metformin has long since been used to treat Type 2 Diabetes and has been shown to be beneficial in several other conditions. Metformin is well-tested in vitro and in vivo and an approved compound that targets diverse pathways including mitochondrial energy production and insulin signaling. There is growing evidence for the benefits of metformin to counteract age-related diseases such as cancer, cardiovascular disease, and neurodegenerative diseases. We will discuss evidence showing that certain neurodegenerative diseases and diabetes are explicitly linked and that metformin along with other diabetes drugs can reduce neurological symptoms in some patients and reduce disease phenotypes in animal and cell models. An interesting therapeutic factor might be how metformin is able to balance survival and death signaling in cells through pathways that are commonly associated with neurodegenerative diseases. In healthy neurons, these overarching signals keep energy metabolism, oxidative stress, and proteostasis in check, avoiding the dysfunction and neuronal death that defines neurodegenerative disease. We will discuss the biological mechanisms involved and the relevance of neuronal vulnerability and potential difficulties for future trials and development of therapies.

The Therapeutic Potential of Metformin in Neurodegenerative Diseases

The search for treatments for neurodegenerative diseases is a major concern in light of today's aging population and an increasing burden on individuals, families, and society. Although great advances have been made in the last decades to understand the underlying genetic and biological cause of these diseases, only some symptomatic treatments are available. Metformin has long since been used to treat Type 2 Diabetes and has been shown to be beneficial in several other conditions. Metformin is well-tested in vitro and in vivo and an approved compound that targets diverse pathways including mitochondrial energy production and insulin signaling. There is growing evidence for the benefits of metformin to counteract age-related diseases such as cancer, cardiovascular disease, and neurodegenerative diseases. We will discuss evidence showing that certain neurodegenerative diseases and diabetes are explicitly linked and that metformin along with other diabetes drugs can reduce neurological symptoms in some patients and reduce disease phenotypes in animal and cell models. An interesting therapeutic factor might be how metformin is able to balance survival and death signaling in cells through pathways that are commonly associated with neurodegenerative diseases. In healthy neurons, these overarching signals keep energy metabolism, oxidative stress, and proteostasis in check, avoiding the dysfunction and neuronal death that defines neurodegenerative disease. We will discuss the biological mechanisms involved and the relevance of neuronal vulnerability and potential difficulties for future trials and development of therapies.

Comparison of a Rat Primary Cell-Based Blood-Brain Barrier Model With Epithelial and Brain Endothelial Cell Lines: Gene Expression and Drug Transport

Cell culture-based blood-brain barrier (BBB) models are useful tools for screening of CNS drug candidates. Cell sources for BBB models include primary brain endothelial cells or immortalized brain endothelial cell lines. Despite their well-known differences, epithelial cell lines are also used as surrogate models for testing neuropharmaceuticals. The aim of the present study was to compare the expression of selected BBB related genes including tight junction proteins, solute carriers (SLC), ABC transporters, metabolic enzymes and to describe the paracellular properties of nine different culture models. To establish a primary BBB model rat brain capillary endothelial cells were co-cultured with rat pericytes and astrocytes (EPA). As other BBB and surrogate models four brain endothelial cells lines, rat GP8 and RBE4 cells, and human hCMEC/D3 cells with or without lithium treatment (D3 and D3L), and four epithelial cell lines, native human intestinal Caco-2 and high P-glycoprotein expressing vinblastine-selected VB-Caco-2 cells, native MDCK and MDR1 transfected MDCK canine kidney cells were used. To test transporter functionality, the permeability of 12 molecules, glucopyranose, valproate, baclofen, gabapentin, probenecid, salicylate, rosuvastatin, pravastatin, atorvastatin, tacrine, donepezil, was also measured in the EPA and epithelial models. Among the junctional protein genes, the expression level of occludin was high in all models except the GP8 and RBE4 cells, and each model expressed a unique claudin pattern. Major BBB efflux (P-glycoprotein or ABCB1) and influx transporters (GLUT-1, LAT-1) were present in all models at mRNA levels. The transcript of BCRP (ABCG2) was not expressed in MDCK, GP8 and RBE4 cells. The absence of gene expression of important BBB efflux and influx transporters BCRP, MRP6, -9, MCT6, -8, PHT2, OATPs in one or both types of epithelial models suggests that Caco-2 or MDCK models are not suitable to test drug candidates which are substrates of these transporters. Brain endothelial cell lines GP8, RBE4, D3 and D3L did not form a restrictive paracellular barrier necessary for screening small molecular weight pharmacons. Therefore, among the tested culture models, the primary cell-based EPA model is suitable for the functional analysis of the BBB.

Randomised controlled trial of simvastatin treatment for autism in young children with neurofibromatosis type 1 (SANTA)

Background

Neurofibromatosis 1 (NF1) is a monogenic model for syndromic autism. Statins rescue the social and cognitive phenotype in animal knockout models, but translational trials with subjects > 8 years using cognition/behaviour outcomes have shown mixed results. This trial breaks new ground by studying statin effects for the first time in younger children with NF1 and co-morbid autism and by using multiparametric imaging outcomes.

Methods

A single-site triple-blind RCT of simvastatin vs. placebo was done. Assessment (baseline and 12-week endpoint) included peripheral MAPK assay, awake magnetic resonance imaging spectroscopy (MRS; GABA and glutamate+glutamine (Glx)), arterial spin labelling (ASL), apparent diffusion coefficient (ADC), resting state functional MRI, and autism behavioural outcomes (Aberrant Behaviour Checklist and Clinical Global Impression).

Results

Thirty subjects had a mean age of 8.1 years (SD 1.8). Simvastatin was well tolerated. The amount of imaging data varied by test. Simvastatin treatment was associated with (i) increased frontal white matter MRS GABA (t(12) = - 2.12, p = .055), GABA/Glx ratio (t(12) = - 2.78, p = .016), and reduced grey nuclei Glx (ANCOVA p < 0.05, Mann-Whitney p < 0.01); (ii) increased ASL perfusion in ventral diencephalon (Mann-Whitney p < 0.01); and (iii) decreased ADC in cingulate gyrus (Mann-Whitney p < 0.01). Machine-learning classification of imaging outcomes achieved 79% (p < .05) accuracy differentiating groups at endpoint against chance level (64%, p = 0.25) at baseline. Three of 12 (25%) simvastatin cases compared to none in placebo met 'clinical responder' criteria for behavioural outcome.

Conclusions

We show feasibility of peripheral MAPK assay and autism symptom measurement, but the study was not powered to test effectiveness. Multiparametric imaging suggests possible simvastatin effects in brain areas previously associated with NF1 pathophysiology and the social brain network.

Trial registration

EU Clinical Trial Register (EudraCT) 2012-005742-38 (www.clinicaltrialsregister.eu).

Post-Operative Cognitive Dysfunction: An exploration of the inflammatory hypothesis and novel therapies

Post-Operative Cognitive Dysfunction (POCD) is a highly prevalent condition with significant clinical, social and financial impacts for patients and their communities. The underlying pathophysiology is becoming increasingly understood, with the role of neuroinflammation and oxidative stress secondary to surgery and anaesthesia strongly implicated. This review aims to describe the putative mechanisms by which surgery-induced inflammation produces cognitive sequelae, with a focus on identifying potential novel therapies based upon their ability to modify these pathways.

The renin-angiotensin system: a possible new target for depression

Depression remains a debilitating condition with an uncertain aetiology. Recently, attention has been given to the renin-angiotensin system. In the central nervous system, angiotensin II may be important in multiple pathways related to neurodevelopment and regulation of the stress response. Studies of drugs targeting the renin-angiotensin system have yielded promising results. Here, we review the potential beneficial effects of angiotensin blockers in depression and their mechanisms of action. Drugs blocking the angiotensin system have efficacy in several animal models of depression. While no randomised clinical trials were found, case reports and observational studies showed that angiotensin-converting enzyme inhibitors or angiotensin receptor blockers had positive effects on depression, whereas other antihypertensive agents did not. Drugs targeting the renin-angiotensin system act on inflammatory pathways implicated in depression. Both preclinical and clinical data suggest that these drugs possess antidepressant properties. In light of these results, angiotensin system-blocking agents offer new horizons in mood disorder treatment.

Pharmacological Approaches to the Management of Secondary Progressive Multiple Sclerosis

It is well recognised that the majority of the impact of multiple sclerosis (MS), both personal and societal, arises in the progressive phase where disability accumulates inexorably. As such, progressive MS (PMS) has been the target of pharmacological therapies for many years. However, there are no current licensed treatments for PMS. This stands in marked contrast to relapsing remitting MS (RRMS) where trials have resulted in numerous licensed therapies. PMS has proven to be a more difficult challenge compared to RRMS and this review focuses on secondary progressive MS (SPMS), where relapses occur before the onset of gradual, irreversible disability, and not primary progressive MS where disability accumulation occurs without prior relapses. Although there are similarities between the two forms, in both cases pinpointing when PMS starts is difficult in a condition in which disability can vary from day to day. There is also an overlap between the pathology of relapsing and progressive MS and this has contributed to the lack of well-defined outcomes, both surrogates and clinically relevant outcomes in PMS. In this review, we used the search term 'randomised controlled clinical drug trials in secondary progressive MS' in publications since 1988 together with recently completed trials where results were available. We found 34 trials involving 21 different molecules, of which 38% were successful in reaching their primary outcome. In general, the trials were well designed (e.g. double blind) with sample sizes ranging from 35 to 1949 subjects. The majority were parallel group, but there were also multi-arm and multidose trials as well as the more recent use of adaptive designs. The disability outcome most commonly used was the Expanded Disability Status Scale (EDSS) in all phases, but also magnetic resonance imaging (MRI)-measured brain atrophy has been utilised as a surrogate endpoint in phase II studies. The majority of the treatments tested in SPMS over the years were initially successful in RRMS. This has a number of implications in terms of targeting SPMS, but principally implies that the optimal strategy to target SPMS is to utilise the prodrome of relapses to initiate a therapy that will aim to both prevent progression and slow its accumulation. This approach is in agreement with the early targeting of MS but requires treatments that are both effective and safe if it is to be used before disability is a major problem. Recent successes will hopefully result in the first licensed therapy for PMS and enable us to test this approach.

Rosuvastatin ameliorates cognitive impairment in rats fed with high-salt and cholesterol diet via inhibiting acetylcholinesterase activity and amyloid beta peptide aggregation

Amyloid beta (Aβ) peptide aggregation and cholinergic neurodegeneration are involved in the development of cognitive impairment. Therefore, in this article, we examined rosuvastatin (RSV), an oral hypolipidemic drug, to determine its potential as a dual inhibitor of acetylcholinesterase (AChE) and Aβ peptide aggregation for the treatment of cognitive impairment. Molecular docking study was done to examine the affinity of RSV with Aβ_1-42 and AChE in silico. We also employed neurobehavioral activity tests, biochemical estimation, and histopathology to study the anti-Aβ_1-42 aggregation capability of RSV in vivo. Molecular docking study provided evidence that RSV has the best binding conformer at its receptor site or active site of an enzyme. The cognitive impairment in female Wistar rats was induced by high-salt and cholesterol diet (HSCD) ad libitum for 8 weeks. RSV ameliorated serum cholesterol level, AChE activity, and Aβ_1-42 peptide aggregations in HSCD induced cognitive impairment. In addition, RSV-treated rats showed greater scores in the open field (locomotor activity) test. Moreover, the histopathological studies in the hippocampus and cortex of rat brain also supported that RSV markedly reduced the cognitive impairment and preserved the normal histoarchitectural pattern of the hippocampus and cortex. Taken together, these data indicate that RSV may act as a dual inhibitor of AChE and Aβ_1-42 peptide aggregation, therefore suggesting a therapeutic strategy for cognitive impairment treatment.

Current insights into pathogenesis of Parkinson's disease: Approach to mevalonate pathway and protective role of statins

Although Parkinson's disease (PD) is considered as the second most common life threatening age-related neurodegenerative disorder, but the underlying mechanisms for pathogenesis of PD are remained to be fully found. However, a complex relationship between genetic and environmental predisposing factors are involved in progression of PD. Dopaminergic neuronal cell death caused by mutations and accumulation of α-synuclein in Lewy bodies and neurites was suggested as the main strategy for PD, but current studies have paid attention to the role of mevalonate pathway in incidence of neurodegenerative diseases including PD. The discovery may change the therapeutic protocols from symptomatic treatment by dopamine precursors and agonists to neurodegenerative process halting drugs. Moreover, the downstream metabolites of mevalonate pathway may be used as diagnostic biomarkers for early diagnosis of PD. Statins, as cholesterol lowering drugs, may ameliorate the enzyme complex dysfunction, a key step in the progression of the neurodegenerative disorders, oxidative stress-induced damage and neuro-inflammation. Statins exert the neuroprotective effects on striatal dopaminergic neurons through blocking the mevalonate pathway. In the present review, we have focused on the new approaches to pathogenesis of PD regarding to mevalonate pathway, in addition to the previous understood mechanisms for the disease. It tries to elucidate the novel findings about PD for the development of future diagnostic and therapeutic strategies. Moreover, we explain the controversial role of statins in improvement or progression of PD and the position of these drugs in neuroprotection in PD patients.

Pravastatin Chronic Treatment Sensitizes Hypercholesterolemic Mice Muscle to Mitochondrial Permeability Transition: Protection by Creatine or Coenzyme Q10

Statins are efficient cholesterol-lowering medicines utilized worldwide. However, 10% of patients suffer from adverse effects specially related to skeletal muscle function. Pro- or anti-oxidant effects of statins have been reported. Here we hypothesized that statins induce muscle mitochondrial oxidative stress leading to mitochondrial permeability transition (MPT) which may explain statin muscle toxicity. Thus, our aims were to investigate the effects of statin chronic treatment on muscle mitochondrial respiration rates, MPT and redox state indicators in the context of hypercholesterolemia. For this purpose, we studied muscle biopsies of the hypercholesterolemic LDL receptor knockout mice (LDLr^-/-) treated with pravastatin during 3 months. Plantaris, but not soleus muscle of treated mice showed significant inhibition of respiration rates induced by ADP (–14%), oligomycin (–20%) or FCCP (–40%). Inhibitions of respiratory rates were sensitive to EGTA (Ca²⁺ chelator), cyclosporin A (MPT inhibitor), ruthenium red (inhibitor of mitochondria Ca²⁺ uptake) and coenzyme Q₁₀ (antioxidant), indicating that pravastatin treatment favors Ca²⁺ induced MPT. Diet supplementation with creatine (antioxidant) also protected treated mice against pravastatin sensitization to Ca²⁺ induced MPT. Among several antioxidant enzymes analyzed, only catalase activity was increased by 30% in plantaris muscle of pravastatin treated mice. Oxidized lipids, but not proteins biomarkers were identified in treated LDLr^-/- plantaris muscle. Taken together, the present results suggest that chronic pravastatin administration to a model of familial hypercholesterolemia promotes mitochondrial dysfunctions in plantaris muscle that can be counteracted by antioxidants administered either in vitro (CoQ₁₀) or in vivo (creatine). Therefore, we propose that inhibition of muscle mitochondrial respiration by pravastatin leads to an oxidative stress that, in the presence of calcium, opens the permeability transition pore. This mitochondrial oxidative stress caused by statin treatment also signals for cellular antioxidant system responses such as catalase upregulation. These results suggest that the detrimental effects of statins on muscle mitochondria could be prevented by co-administration of a safe antioxidant such as creatine or CoQ10.

Effects of Atorvastatin on Serum High-Sensitive C-Reactive Protein and Total Cholesterol Levels in Asian Patients With Atrial Fibrillation

Elevated serum levels of high-sensitive C-reactive protein (hs-CRP) and total cholesterol (TC) correlate with atherosclerotic vascular disease and increased frequency of vascular events. In this study, we investigated the effect of atorvastatin treatment on serum hs-CRP and TC levels, and the recurrence rate of atrial fibrillation (AF) in patients. Furthermore, a meta-analysis was performed to confirm the findings in this study. A total of 105 patients with AF were recruited to this study, including 55 patients with AF who were treated with amiodarone and atorvastatin (the treatment group) and 50 patients with AF who were treated with only amiodarone (the control group). Patients were treated for 12 months and followed up regularly for 1 year. Serum hs-CRP and TC levels in patients before and after treatment were recorded, and AF recurrence rate at 3, 6, and 12 months of treatment was obtained. Statistical analyses were performed with R 3.1.0 software and STATA 12.0 software. For patients in both treatment and control groups, serum hs-CRP and TC levels were high before the treatments began (both P < 0.05). However, after 12 months of treatment, serum hs-CRP and TC levels in the treatment group was dramatically reduced compared with the control group (hs-CRP: 3.63 ± 2.14 mg/L vs. 2.75 ± 1.89 mg/L, t = 2.24, P = 0.027; TC: 4.66 ± 1.13 mmol/L vs. 4.20 ± 1.06 mmol/L, t = 2.15, P = 0.034). After 12 months of treatment, the AF recurrence rate in the treatment group was significantly lower than the control group (16.4% vs. 34.0%; χ = 4.37; P = 0.037). In addition, 13 studies were selected for meta-analysis. Pooled results of the meta-analysis showed that serum hs-CRP and TC levels decreased significantly in the treatment group compared with the case group [hs-CRP: SMD = 0.95, 95% confidence interval (CI) = 0.62-1.29, and P < 0.001; TC: SMD = 1.39, 95% CI = 0.65-2.13, and P < 0.001]. Our study presents compelling evidence that atorvastatin is highly effective in reducing serum hs-CRP and TC levels and lowering the recurrence rate of AF.

The Effect of Statins on Rate of Cognitive Decline in Mild Cognitive Impairment

Introduction

This study's aims are to identify whether a relationship between statin use and rate of cognitive decline exists. The relationship between statins and mild cognitive impairment (MCI) has been investigated in the past with the evidence showing mixed results.

Methods

Seven hundred sixty-eight subjects were identified with MCI. Subjects were stratified into six possible groups according to apolipoprotein E (APOE) ε4 allele status and statin use and assessed for decline in cognitive function.

Results

All cognitive assessments trended toward less decline with statin use. Alzheimer’s Disease Assessment Scale 11 (ADAS 11) showed the biggest difference in mean change between statin users and nonusers (−0.82 vs. −1.22, respectively). Change reached marginal significance on the ADAS 11 when stratified by APOE ε4–negative subjects.

Discussion

All cognitive assessments trended toward less decline when subjects were concurrently treated with a statin, supporting the position that statins do not have a net negative effect on cognitive assessment and suggesting a potential treatment benefit.

Statin-induced changes in mitochondrial respiration in blood platelets in rats and human with dyslipidemia

3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) are widely used drugs for lowering blood lipid levels and preventing cardiovascular diseases. However, statins can have serious adverse effects, which may be related to development of mitochondrial dysfunctions. The aim of study was to demonstrate the in vivo effect of high and therapeutic doses of statins on mitochondrial respiration in blood platelets. Model approach was used in the study. Simvastatin was administered to rats at a high dose for 4 weeks. Humans were treated with therapeutic doses of rosuvastatin or atorvastatin for 6 weeks. Platelet mitochondrial respiration was measured using high-resolution respirometry. In rats, a significantly lower physiological respiratory rate was found in intact platelets of simvastatin-treated rats compared to controls. In humans, no significant changes in mitochondrial respiration were detected in intact platelets; however, decreased complex I-linked respiration was observed after statin treatment in permeabilized platelets. We propose that the small in vivo effect of statins on platelet energy metabolism can be attributed to drug effects on complex I of the electron transport system. Both intact and permeabilized platelets can be used as a readily available biological model to study changes in cellular energy metabolism in patients treated with statins.

Human sterol 14α-demethylase as a target for anticancer chemotherapy: towards structure-aided drug design

Rapidly multiplying cancer cells synthesize greater amounts of cholesterol to build their membranes. Cholesterol-lowering drugs (statins) are currently in clinical trials for anticancer chemotherapy. However, given at higher doses, statins cause serious side effects by inhibiting the formation of other biologically important molecules derived from mevalonate. Sterol 14α-demethylase (CYP51), which acts 10 steps downstream, is potentially a more specific drug target because this portion of the pathway is fully committed to cholesterol production. However, screening a variety of commercial and experimental inhibitors of microbial CYP51 orthologs revealed that most of them (including all clinical antifungals) weakly inhibit human CYP51 activity, even if they display high apparent spectral binding affinity. Only one relatively potent compound, (R)-N-(1-(3,4'-difluorobiphenyl-4-yl)-2-(1H-imidazol-1-yl)ethyl)-4-(5-phenyl-1,3,4-oxadiazol-2-yl)benzamide (VFV), was identified. VFV has been further tested in cellular experiments and found to decrease proliferation of different cancer cell types. The crystal structures of human CYP51-VFV complexes (2.0 and 2.5 Å) both display a 2:1 inhibitor/enzyme stoichiometry, provide molecular insights regarding a broader substrate profile, faster catalysis, and weaker susceptibility of human CYP51 to inhibition, and outline directions for the development of more potent inhibitors.

Statins Reduce the Risks of Relapse to Addiction in Rats

Statins are drugs that have been used for decades in humans for the treatment of hypercholesterolemia. More recently, several lines of evidence demonstrate that statins, in addition to their peripheral effects, produce a wide variety of effects in the brain and may be beneficial in neurological and psychiatric conditions. In this study, we allowed rats to self-administer cocaine for several weeks and, at the end of self-administration training, we treated them with low doses of statins daily for a 21-day period of abstinence. Chronic administration of brain-penetrating statins, simvastatin (1 mg/kg) and atorvastatin (1 mg/kg), reduced cocaine seeking compared with vehicle, whereas administration of pravastatin (2 mg/kg), a statin with low brain penetrability, did not. Importantly, the effects of brain-penetrating statins persisted even after discontinuation of the treatment and were specific for drug seeking because drug taking was not altered by simvastatin treatment. Finally, the effects of simvastatin were found to generalize to another drug of abuse such as nicotine, but not to food reward, and to reinstatement of cocaine seeking induced by stress. These results demonstrate that brain-penetrating statins can reduce risks of relapse to addiction. Given their well-known safety profile in humans, statins could be a novel effective treatment for relapse to cocaine and nicotine addiction and their use could be implemented in clinical settings without major health risks.

Statin Use and the Risk of Parkinson's Disease: An Updated Meta-Analysis

INTRODUCTION

In response to the ongoing debate over the relationship between the use of statins and the risk of Parkinson's disease (PD), we performed a systematic review and meta-analysis of observational studies to examine their association.

METHODS

We conducted a review of the literature using electronic databases supplemented by a manual search to identify potentially relevant case-control or cohort studies. Summary relative risk (RRs) and 95% confidence intervals (CIs) were calculated using a random-effects model. Sensitivity and subgroup analyses were also conducted.

RESULTS

Eleven studies (five case-control and six cohort) with a total of 3,513,209 participants and 21,011 PD cases were included. Statin use was associated with a lower risk of PD, with a summary RR of 0.81 (95% CI 0.71-0.92). Sensitivity analysis demonstrated the robustness of results. Subgroup analyses showed that neither study design nor study region significantly influenced the effect estimates. However, subgroup studies adjusted for age or sex had a greater inverse association than did unadjusted analyses (age-adjusted RR 0.75, 95% CI 0.60-0.95; age-unadjusted RR 0.86, 95% CI 0.75-0.99 and sex-adjusted RR 0.76, 95% CI 0.59-0.98; sex-unadjusted RR 0.85, 95% CI 0.79-0.92).

CONCLUSIONS

Results of this systematic review suggest that statin use is associated with a reduced PD risk. However, randomized controlled trials and more observational studies should be performed before strong conclusions are drawn.

Exploring novel AEDs from drugs used for treatment of non-epileptic disorders

Epilepsy is a chronic neurological disease. Although many anti-epileptic drugs (AEDs) have been developed for clinical use, they have no effect on 20-30% of patients and do not generally prevent epileptogenesis. Because of the long development cycle for new AEDs and the high cost, increasing efforts are being made to find anti-epileptic effects among drugs that are already listed for the treatment of other diseases and repurpose them as potential anti-epileptic treatments. Here, we review the progress that has been made in this field as a result of animal and clinical trials of drugs such as rapamycin, everolimus, losartan, celecoxib, bumetanide and other non-epileptic drugs. These drugs can prevent the epileptogenesis, reduce the epileptic pathological changes, and even be used to treat intractable epilepsy. Their mechanisms of action are completely different from those of existing AEDs, prompting researchers to change their perspectives in the search for new AEDs.

Temporal profiles of blood pressure, circulating nitric oxide, and adrenomedullin as predictors of clinical outcome in acute ischemic stroke patients

Stroke remains an important health and social challenge. The present study investigated whether blood pressure (BP) parameters and circulating levels of nitric oxide metabolites (NOx) and adrenomedullin (AM) may predict clinical outcomes of stroke. Patients (n=76) diagnosed with acute ischemic stroke were admitted to the stroke unit and clinical history data and monitored parameters were recorded. Blood plasma was collected at days 1, 2, and 7 to measure NOx and AM levels. Infarct volume, neurological severity [on the National Institutes of Health Stroke Scale (NIHSS)], and functional prognosis (on the Rankin scale) were measured as clinical outcomes. Patients with higher BP had more severe symptoms (NIHSS >3; P<0.01) and BP variability predicted neurological severity and growth of infarct volume. NOx values were significantly lower in stroke patients than in healthy controls (P<0.01). An increase in NOx levels from day 1 to day 2 was beneficial for the patients as measured by NIHSS at 7 days and 3 months, and by Rankin at 3 months [odds ratio (OR), 0.91] whereas a steep increase from day 2 to day 7 was detrimental and associated with an increase in infarct volume (OR, 35.3). AM levels were significantly higher in patients at day 1 and 2 than in healthy individuals (P<0.01) and these levels returned to normal at day 7. Patients with high AM levels at day 2 had significantly higher NIHSS scores measured at day 1 (P<0.05) and 7 (P<0.01). A receiving operating characteristic curve analysis identified that AM levels at day 2 of >522.13 pg/ml predicted increased neurological severity at day 7 (area under the curve=0.721). Multivariate logistic regression indicated that AM levels at day 2 predicted increased neurological severity at 7 days and at 3 months. BP parameters and changing levels for NOx and AM predicted long-term clinical outcomes as measured by infarct volume, neurological severity scale, and functional prognosis.

Antioxidant effect of simvastatin throught oxidative imbalance caused by lisdexamfetamine dimesylate

The present study aims to directly investigate the behavioral and antioxidant effects of simvastatin in a model of bipolar mania induced by lisdexamfetamine dimesylate. Wistar rats were treated for 30 days with simvastatin. On the 24th day after the start of treatment, each rat was administered lisdexamfetamine dimesylate for 7 days. The results suggest that simvastatin combined with lisdexamfetamine dimesylate induced a significant increased locomotion and lisdexamfetamine dimesylate administration causes an oxidative imbalance determined by an increment in lipid peroxidation, protein oxidation and alterations in the activities of antioxidant enzymes in brain areas; moreover, in the presence of simvastatin, most of these effects were prevented. These findings contribute to a better understanding of the critical roles of lisdexamfetamine dimesylate in the treatment of neuropsychiatric disorders, associated with increased oxidative stress and changes in antioxidant enzymatic defense. In view of the central role played by lisdexamfetamine dimesylate, the established antioxidant effect of simvastatin therapy is of major interest.