Inhibitory effect of statins on inflammatory cytokine production from human bronchial epithelial cells

The Association between Statins Intake and Risk of Post Stroke Pneumonia: A Systematic Review and Meta-Analysis

AIM

This research aimed to examine the relationship between the intake of statins and the risk of post-stroke pneumonia in a systematic review and meta-analysis study.

METHODS

An extensive search of published articles on March 21st, 2023, was done in several databases, like Web of Science (ISI), PubMed, Cochrane Library, Embase, Scopus, and Google Scholar. The Newcastle Ottawa Scale (NOS) checklist was employed to evaluate the quality of observational studies. Statistical tests (Chi-square test and I2) and graphical techniques (Forest plot) were used to determine whether heterogeneity existed in the meta-analysis studies. Funnel plots and Begg and Egger's tests were used to assess the publication bias.

RESULTS

Seven studies (5 cohort and 2 case-control studies) were retrieved to examine the association between statins and post-stroke pneumonia. The sample size of the studies compiled in the meta- analysis was obtained to be 68,966 participants. Meta-analysis demonstrated that the overall odds of post-stroke pneumonia in the statin group was equal to 0.87 (95% CI: 0.67 - 1.13; p-value 0.458). Subgroup analysis indicated that the odds of post-stroke pneumonia in the statin group was equal to 0.93 (95% CI: 0.73-1.18; p-value = 0.558) in the cohort studies, and equal to 0.92 (95% CI: 0.37-2.26; p-value = 0.857) in the case-control studies. The examination of the association between the intake of statins and post-stroke pneumonia showed no evidence of publication bias (Begg's test, p-value = 0.368; Eggers test, p-value = 0.282).

CONCLUSION

In this study, no relationship has been observed between receiving statins and the risk of post-stroke pneumonia.

Pravastatin attenuates isoprenaline induced cardiac fibrosis in a mouse model

We investigated the effects of pravastatin (PRAVA) on isoprenaline (ISP) induced cardiac fibrosis using four groups of mice: untreated control, PRAVA, ISP, ISP + PRAVA groups. ISP, 20 mg/kg, was administered subcutaneously daily for 14 days. PRAVA, 20 mg/kg, was administered orally daily for 14 days. Mice were sacrificed on day15 and heart and blood samples were collected to investigate cardiac injury markers. The mean body weight for the ISP group on day 15 was decreased significantly compared to day 0; PRAVA increased the mean body weight slightly on day 15 of treatment compared to day 0. The heart:body weight ratio was increased in the ISP group compared to the control group, but the ratio was returned to near control ratio in the PRAVA + ISP group. The serum creatine kinase-myocardial band (CK-MB) level was reduced significantly in the PRAVA + ISP group compared to the ISP group. Serum triglyceride level was decreased significantly in ISP + PRAVA group compared to the ISP group. PRAVA administration significantly reduced tissue collagen I and III levels in the ISP + PRAVA group compared to the ISP group. Lipid oxidation was decreased and reduced glutathione activity was increased in the PRAVA + ISP group compared to the ISP group. IL-6, α-SMA, CTGF, TGF-β and SMAD-3 gene expressions were decreased in the PRAVA + ISP group compared to the ISP group. We found fewer inflammatory cells and less fibrosis in heart tissue in the PRAVA + ISP group compared to the ISP group. PRAVA decreased ISP induced cardiac fibrosis by reducing oxidative stress, collagen deposition and inflammation, as well as by decreasing expression of TGF-β, SMAD-3 and CTGF genes.

Previous use of statins does not improve the outcome of bloodstream infection after kidney transplantation

Previous studies have suggested that exposure to statins confers a protective effect in bloodstream infection (BSI) due to the anti-inflammatory and immunomodulatory properties attributed to these lipid-lowering drugs. Scarce evidence is available for the solid organ transplant population. Therefore, we compared the time to clinical cure (primary outcome) and the time to fever resolution, new requirement of intensive care unit admission or renal replacement therapy, and 30-day all-cause mortality (secondary outcomes) between kidney transplant (KT) recipients with post-transplant BSI that were receiving or not statin therapy for at least the previous 30 days. We included 80 KT recipients that developed 109 BSI episodes (43 [39.4%] and 66 [60.6%] episodes within the statin and non-statin groups, respectively). The median interval since the initial prescription to BSI was 512 days (interquartile range [IQR]: 172-1388). Most episodes were of urinary source and due to Enterobacterales. There were no differences in the median time to clinical cure in the statin and non-statin groups (3.4 [IQR: 3-6.8] versus 4 [IQR: 2-6] days; p-value = .112). The lack of effect was confirmed by multiple linear regression analysis adjusted for confounding factors (standardized β coefficient = 0.040; p-value = .709). No significant differences were observed for any of the secondary outcomes either. Vital signs and laboratory values at BSI onset and after 72-96 h were similar in both groups. In conclusion, previous statin therapy had no apparent protective effect on the outcome of post-transplant BSI among KT recipients.

Lipopolysaccharide and statin-mediated immune-responsive protein networks revealed in macrophages through affinity purification spacer-arm controlled cross-linking (AP-SPACC) proteomics

Toll-like receptor 4 (TLR4), a pattern recognition receptor, is activated by lipopolysaccharides (LPS) and induces the MyD88 pathway, which subsequently produces pro-inflammatory cytokines through activation of transcriptional nuclear factor (NF)-κB. Statins have been widely prescribed to reduce cholesterol synthesis for patients with cardiovascular disease. Statins may have pleiotropic effects, which include anti- and pro-inflammatory effects on cells. The molecular mechanism of the sequential influence of LPS and statin on the innate immune system remains unknown. We employed affinity purification-spacer-arm controlled cross-linking (AP-SPACC) MS-based proteomics analysis to identify the LPS- and statin-LPS-responsive proteins and their networks. LPS-stimulated RAW 264.7 macrophage cells singly and combined with the drug statin used in this study. Two chemical cross-linkers with different spacer chain lengths were utilized to stabilize the weak and transient interactors. Proteomic analysis identified 1631 differentially expressed proteins. We identified 151 immune-response proteins through functional enrichment analysis and visualized their interaction networks. Selected candidate protein-coding genes were validated, specifically squamous cell carcinoma antigens recognized by T cells 3, sphingosine-1-phosphate lyase 1, Ras-related protein Rab-35, and tumor protein D52 protein-coding genes through transcript-level expression analysis. The expressions of those genes were significantly increased upon statin treatment and decreased in LPS-stimulated macrophage cells. Therefore, we presumed that the expression changes of genes occurred due to immune response during activation of inflammation. These results highlight the immune-responsive proteins network, providing a new platform for novel investigations and discovering future therapeutic targets for inflammatory diseases.

Statin and aspirin as adjuvant therapy in hospitalised patients with SARS-CoV-2 infection: a randomised clinical trial (RESIST trial)

Background

Statins and aspirin have been proposed for treatment of COVID-19 because of their anti-inflammatory and anti-thrombotic properties. Several observational studies have shown favourable results. There is a need for a randomised controlled trial.

Methods

In this single-center, open-label, randomised controlled trial, 900 RT-PCR positive COVID-19 patients requiring hospitalisation, were randomly assigned to receive either atorvastatin 40 mg (Group A, n = 224), aspirin 75 mg (Group B, n = 225), or both (Group C, n = 225) in addition to standard of care for 10 days or until discharge whichever was earlier or only standard of care (Group D, n = 226). The primary outcome variable was clinical deterioration to WHO Ordinal Scale for Clinical Improvement ≥ 6. The secondary outcome was change in serum C-reactive protein, interleukin-6, and troponin I.

Results

The primary outcome occurred in 25 (2.8%) patients: 7 (3.2%) in Group A, 3 (1.4%) in Group B, 8 (3.6%) in Group C, and 7 (3.2%) in Group D. There was no difference in primary outcome across the study groups (P = 0.463). Comparison of all patients who received atorvastatin or aspirin with the control group (Group D) also did not show any benefit [Atorvastatin: HR 1.0 (95% CI 0.41–2.46) P = 0.99; Aspirin: HR 0.7 (95% CI 0.27–1.81) P = 0.46]. The secondary outcomes revealed lower serum interleukin-6 levels among patients in Groups B and C. There was no excess of adverse events.

Conclusions

Among patients admitted with mild to moderate COVID-19 infection, additional treatment with aspirin, atorvastatin, or a combination of the two does not prevent clinical deterioration.

Trial Registry Number CTRI/2020/07/026791 (http://ctri.nic.in; registered on 25/07/2020)

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07570-5.

Pravastatin attenuates sepsis-induced acute lung injury through decreasing pulmonary microvascular permeability via inhibition of Cav-1/eNOS pathway

BACKGROUND

Disruption of alveolar endothelial barrier caused by inflammation drives the progression of septic acute lung injury (ALI). Pravastatin, an inhibitor of HMG Co-A reductase, has potent anti-inflammatory effects. In the present study, we aim to explore the beneficial role of pravastatin in sepsis-induced ALI and its related mechanisms.

METHODS

A septic ALI model was established by cecal ligation and puncture (CLP) in mice. The pulmonary microvascular endothelial cells (PMVECs) were challenged with lipopolysaccharide (LPS). The pathological changes in lung tissues were examined by HE staining. The pulmonary microvascular permeability was determined by lung wet-to-dry (W/D) weight ratio and Evans blue staining. The total protein concentration in bronchoalveolar lavage fluid (BALF) was detected by BCA assay. The levels of TNF-α, IL-1β, and IL-6 were assessed by qRT-PCR and ELISA. Apoptosis was determined by flow cytometry and TUNEL. Western blotting was performed for detection of target protein levels. The expression of VE-Cadherin in lung tissues was evaluated by immunohistochemical staining.

RESULTS

Pravastatin improved survival rate, attenuated lung pathological changes and reduced pulmonary microvascular permeability in septic mice. In addition, pravastatin restrained sepsis-induced inflammatory response and apoptosis in the lung tissues and PMVECs. Moreover, pravastatin up-regulated the levels of junction proteins ZO-1, JAM-C, and VE-Cadherin. Finally, pravastatin suppressed inflammation, apoptosis and enhanced the expression of junction proteins via regulating Cav-1/eNOS signaling pathway in LPS-exposed PMVECs.

CONCLUSION

Pravastatin ameliorates sepsis-induced ALI through improving alveolar endothelial barrier disruption via modulating Cav-1/eNOS pathway, which may be an effective candidate for treating septic ALI.

Statin use is associated with lower disease severity in COVID-19 infection

We aim to study the association of hyperlipidemia and statin use with COVID-19 severity. We analysed a retrospective cohort of 717 patients admitted to a tertiary centre in Singapore for COVID-19 infection. Clinical outcomes of interest were oxygen saturation ≤ 94% requiring supplemental oxygen, intensive-care unit (ICU) admission, invasive mechanical-ventilation and death. Patients on long term dyslipidaemia medications (statins, fibrates or ezetimibe) were considered to have dyslipidaemia. Logistic regression models were used to study the association between dyslipidaemia and clinical outcomes adjusted for age, gender and ethnicity. Statin treatment effect was determined, in a nested case-control design, through logistic treatment models with 1:3 propensity matching for age, gender and ethnicity. All statistical tests were two-sided, and statistical significance was taken as p < 0.05. One hundred fifty-six (21.8%) patients had dyslipidaemia and 97% of these were on statins. Logistic treatment models showed a lower chance of ICU admission for statin users when compared to non-statin users (ATET: Coeff (risk difference): - 0.12 (- 0.23, - 0.01); p = 0.028). There were no other significant differences in other outcomes. Statin use was independently associated with lower ICU admission. This supports current practice to continue prescription of statins in COVID-19 patients.

Effect of Statins on the Risk of Poststroke Pneumonia: National Population-Based Cohort Study

Purpose

Statins are widely prescribed medications for treatment of dyslipidemia and prevention of cardiovascular disease. Beyond their lipid-lowering property, statins exhibit multiple pleiotropic and antimicrobial effects. We aimed to investigate the effect of statins on the long-term risk of pneumonia after acute ischemic stroke.

Methods

This retrospective observational research was performed using South Korean National Health Insurance Service claim data, which consist of population-based random sampling. We included patients discharged with acute ischemic stroke (I63 in the ICD10) and no prior history of pneumonia. The primary outcome measure was the occurrence of pneumonia determined based on ICD10 code J09–J18. Treatment with statins during follow-up was collected as a time-dependent variable based on prescription records.

Results

A total of 7,001 subjects with acute ischemic stroke and no prior history of pneumonia were included. During the mean 3.96-year follow-up, pneumonia occurred in 1,715 subjects (24.5%). On multivariate time-dependent Cox proportional hazard–regression analyses, significant preventive benefit of treatment with statins against pneumonia was noted (adjusted HR 0.86, 95% CI 0.77–0.97). Compared to no use of statin, adjusted HRs (95% CIs) for current use of low–intermediate high-intensity statins were 0.88 (0.78–0.99) and 0.49 (0.27–0.87), respectively.

Conclusion

Our retrospective national cohort study found reduced risk of poststroke pneumonia with statin therapy after acute ischemic stroke. Our study suggests that treatment with statins may have a preventive effect against the common complication of poststroke pneumonia.

Anti-Proliferative Effect of Statins Is Mediated by DNMT1 Inhibition and p21 Expression in OSCC Cells

Statins, also known as HMG-CoA reductase inhibitors, are a class of cholesterol-lowering drugs and their anti-cancer effects have been studied in different types of malignant diseases. In the present study, we investigated the anti-proliferative effects of statins, including cerivastatin and simvastatin, on oral squamous cell carcinoma (OSCC) cells. Our data showed that statins inhibited the proliferation of three OSCC cell lines in a dose-dependent manner and this growth inhibition was confirmed through G₀/G₁ cell cycle arrest. Accordingly, we found the upregulation of p21 and downregulation of cyclin-dependent kinases, including CDK2, CDK4, and CDK6, in the statin-treated cells. Importantly, we clearly showed that statins were able to inhibit the expression of DNA methyltransferase 1 (DNMT1) and further promote the expression of p21. Taken together, our data demonstrated that the anti-proliferative effect of statins is mediated by suppressing DNMT1 expression, thus promoting p21 expression and leading to G₀/G₁ cell cycle arrest in OSCC cells.

Adjuvant drug-assisted bone healing: Part III - Further strategies for local and systemic modulation

In this third in a series of reviews on adjuvant drug-assisted bone healing, further approaches aiming at influencing the healing process are discussed. Local and systemic modulation of bone metabolism is pursued with use of a number of drugs with completely different indications, which are characterized by a pleiotropic spectrum of action. These include drugs used to treat lipid disorders (HMG-CoA reductase inhibitors), hypertension (ACE inhibitors), osteoporosis (bisphosphonates), cancer (proteasome inhibitors) and others. Potential applications to enhance bone healing are discussed.

Targeting defective pulmonary innate immunity - A new therapeutic option?

Chronic pulmonary conditions now account for 1 in 15 deaths in the US and mortality is increasing. Chronic obstructive pulmonary disease (COPD) is due to become the 3rd largest cause of mortality by 2030 and mortality from other respiratory conditions such as asthma, idiopathic pulmonary fibrosis and cystic fibrosis are not reducing. There is an urgent need for novel therapies to address this problem as many of the current strategies targeting inflammation are not sufficient. The innate immune system of the lung is an important defence against invading pathogens, but in many chronic pulmonary diseases, this system mounts an inappropriate response. In COPD, macrophages are increased in number, but fail to clear pathogens correctly and become highly activated. This leads to increased damage and remodelling of the airways. In idiopathic fibrosis, there is a switch of macrophage phenotype to a cell that promotes abnormal repair. Neutrophils also display dysfunction in COPD where aberrant migratory profiles may lead to increased damage to lung tissue and emphysema; while in cystic fibrosis the proteolytic lung environment damages neutrophil receptors leading to ineffective phagocytosis and migration. Targeting the innate immune system to restore 'normal function' could have enormous benefits. Improving phagocytosis of pathogens could reduce exacerbations and hence the associated decline in lung function, and novel therapeutics such as sulforaphane appear to do this in vitro. Other natural products such as resveratrol and derivatives also have anti-inflammatory properties. Statins have traditionally been used to manage cholesterol levels in hypercholesterolaemia, however these molecules also have beneficial effects on the innate immune cells. Statins have been shown to be anti-inflammatory and restore aberrant neutrophil chemotaxis in aged cells. Other possible agents that may be efficacious are senolytics. These compounds include natural products such as quercetin which have anti-inflammatory properties but can also suppress viral replication. As viruses have been shown to suppress phagocytosis of macrophages, it is possible that these compounds could have benefit during viral exacerbations to protect this innate response. These compounds demonstrate that it is possible to address defective innate responses in the lung but a better understanding of the mechanisms driving defective innate immunity in pulmonary disease may lead to improved therapeutics.

Interleukin-8 in Hyperlipidemia and Coronary Heart Disease in Thai Patients Taking Statin Cholesterol-Lowering Medication While Undergoing Coronary Artery Bypass Grafting Treatment

The role of interleukin-8 (IL-8), a pivotal chemokine in atherogenesis and coronary heart disease (CHD) development, is diverse and remains unclear. This cross-sectional study investigates the association of the IL-8 expression in hyperlipidemia (H) and CHD patients who have been treated with statin cholesterol-lowering drugs while undergoing coronary artery bypass grafting treatment. Fifty-five Thai volunteers including 13 normal (N), 24 H, and 18 CHD patients were enrolled for the investigation. All the CHD patients had been treated continuously with statin cholesterol-lowering medications since the disease was diagnosed and were undergoing coronary bypass grafting approximately one month later. Therefore, the CHD group was representative of a pathogenesis improvement in CHD. The IL8 mRNA expression was determined by real-time quantitative PCR in the peripheral blood mononuclear cells from heparinized blood. The plasma IL-8 levels were assessed by enzyme-linked immunosorbent assay. The result shows that the IL8 mRNA expression in the H group tended to increase; however, in the CHD group, there was a significant decrease (p=0.0111) compared to the N group. The IL8 mRNA expression and the plasma levels in the CHD group were significantly lower than those in the H group (p < 0.05). A significant negative correlation between the IL8 mRNA (r = -0.499) or plasma IL-8 (r = -0.3875) expression and CHD progression was observed (p < 0.05). In conclusion, the transcriptomic and the phenotypic IL-8 expression decreased significantly in the Thai CHD patients who had continuously received statin-group medications compared to the H and N group participants. Therefore, IL-8 should serve as a feasible marker and could be used to evaluate the therapeutic effects of statins and illustrate the pathology of CHD treatment.

The Use of Platelet-Rich Plasma and Rosuvastatin in Wound Healing in Rabbits: A Longitudinal Study

OBJECTIVE

To test the hypothesis that platelet-rich plasma (PRP) improves wound healing in rabbits by analyzing morphologic alterations in lesions with the use of PRP alone or combined with rosuvastatin (RSV).

METHODS

Eight adult male New Zealand rabbits were used in this study. Researchers created four wounds on the back of each rabbit with an 8-mm punch. The control wound was treated with a 0.9% sodium chloride solution. Experimental wounds were treated with PRP, RSV, or both PRP and RSV. Dressings were changed with a new application of PRP and RSV every 4 days for 16 days. Wounds were biopsied on days 0, 7, 10, 14, and 17 for histopathologic evaluation of the scar tissue.

MAIN RESULTS

Histopathology revealed reepithelialization in 100% of wounds treated with PRP alone after 17 days of treatment, compared with 50% of wounds treated with RSV alone and 75% of the wounds treated with PRP and RSV. Further, combining RSV and PRP reduced blood loss. The use of PRP alone induced 100% neovascularization, compared with 50% and 62.5% in wounds treated with PRP and RSV and RSV alone, respectively. All experimental wounds had a higher percentage of collagen fibers on day 17 postlesion when compared with control wounds (78.27% ± 4.69%). There were no significant differences among treatments; however, wounds treated with RSV alone had the lowest amount of collagen fibers (85.98% ± 3.51%). Wounds treated with PRP alone or PRP and RSV had 90.07% ± 6.20% and 90.76% ± 3.51% collagen fibers, respectively.

CONCLUSIONS

The results of this study indicate that PRP elicits higher healing activity in the first 7 days postlesion. Treatments with RSV alone or RSV and PRP did enhance other healing phases.

Pitavastatin Exerts Potent Anti-Inflammatory and Immunomodulatory Effects via the Suppression of AP-1 Signal Transduction in Human T Cells

Statins inhibiting 3-hydroxy-3-methylglutaryl-CoA reductase are the standard treatment for hypercholesterolemia in atherosclerotic cardiovascular disease (ASCVD), mediated by inflammatory reactions within vessel walls. Several studies highlighted the pleiotropic effects of statins beyond their lipid-lowering properties. However, few studies investigated the effects of statins on T cell activation. This study evaluated the immunomodulatory capacities of three common statins, pitavastatin, atorvastatin, and rosuvastatin, in activated human T cells. The enzyme-linked immunosorbent assay (ELISA) and quantitative real time polymerase chain reaction (qRT-PCR) results demonstrated stronger inhibitory effects of pitavastatin on the cytokine production of T cells activated by phorbol 12-myristate 13-acetate (PMA) plus ionomycin, including interleukin (IL)-2, interferon (IFN)-γ, IL-6, and tumor necrosis factor α (TNF-α). Molecular investigations revealed that pitavastatin reduced both activating protein-1 (AP-1) DNA binding and transcriptional activities. Further exploration showed the selectively inhibitory effect of pitavastatin on the signaling pathways of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK), but not c-Jun N-terminal kinase (JNK). Our findings suggested that pitavastatin might provide additional benefits for treating hypercholesterolemia and ASCVD through its potent immunomodulatory effects on the suppression of ERK/p38/AP-1 signaling in human T cells.

Statin Effects on Incidence, Treatment Success, and Mortality of Clostridium difficile Infections

PURPOSE

To review the effects of statin use in patients at risk for or diagnosed with Clostridium difficile infection (CDI) on CDI incidence, treatment success, and mortality.

METHODS

A literature search was performed through January 2019 using the following terms: statins, HMG-CoA inhibitors, Clostridium difficile, Clostridium difficile associated diarrhea, and Clostridium difficile infection. Additional references were identified from a review of literature citations. Studies evaluating statin effects on C difficile-related outcomes were included.

RESULTS

A total of 8 studies were identified for inclusion in this review. All studies were retrospective. Five studies reported the association between statin use and the development of CDI, suggesting that statins may decrease risk of CDI development in patients already on statin. In one study, there was an improved treatment response against CDI with the use of statin. Three retrospective studies evaluated statin use and mortality from CDI and only one study found significant mortality benefit in statin users.

CONCLUSIONS

Statin use may have a protective effect against the development of CDI and improve CDI treatment success; however, it is unclear if use confers a mortality benefit. Current data remain sparse and larger, prospective studies are needed to confirm current results and identify the specific population that may benefit the most from this intervention.

Heme oxygenase-1-Dependent anti-inflammatory effects of atorvastatin in zymosan-injected subcutaneous air pouch in mice

Statins exert pleiotropic and beneficial anti-inflammatory and antioxidant effects. We have previously reported that macrophages treated with statins increased the expression of heme oxygenase-1 (HO-1), an inducible anti-inflammatory and cytoprotective stress protein, responsible for the degradation of heme. In the present study, we investigated the effects of atorvastatin on inflammation in mice and analyzed its mechanism of action in vivo. Air pouches were established in 8 week-old female C57BL/6J mice. Atorvastatin (5 mg/kg, i.p.) and/or tin protoporphyrin IX (SnPPIX), a heme oxygenase inhibitor (12 mg/kg, i.p.), were administered for 10 days. Zymosan, a cell wall component of Saccharomyces cerevisiae, was injected in the air pouch to trigger inflammation. Cell number and levels of inflammatory markers were determined in exudates collected from the pouch 24 hours post zymosan injection by flow cytometry, ELISA and quantitative PCR. Analysis of the mice treated with atorvastatin alone displayed increased expression of HO-1, arginase-1, C-type lectin domain containing 7A, and mannose receptor C-type 1 in the cells of the exudate of the air pouch. Flow cytometry analysis revealed an increase in monocyte/macrophage cells expressing HO-1 and in leukocytes expressing MRC-1 in response to atorvastatin. Mice treated with atorvastatin showed a significant reduction in cell influx in response to zymosan, and in the expression of proinflammatory cytokines and chemokines such as interleukin-1α, monocyte chemoattractant protein-1 and prostaglandin E₂. Co-treatment of mice with atorvastatin and tin protoporphyrin IX (SnPPIX), an inhibitor of heme oxygenase, reversed the inhibitory effect of statin on cell influx and proinflammatory markers, suggesting a protective role of HO-1. Flow cytometry analysis of air pouch cell contents revealed prevalence of neutrophils and to a lesser extent of monocytes/macrophages with no significant effect of atorvastatin treatment on the modification of their relative proportion. These findings identify HO-1 as a target for the therapeutic actions of atorvastatin and highlight its potential role as an in vivo anti-inflammatory agent.

Toll-Like Receptor-4 Disruption Suppresses Adipose Tissue Remodeling and Increases Survival in Cancer Cachexia Syndrome

Cancer-induced cachexia, characterized by systemic inflammation, body weight loss, adipose tissue (AT) remodeling and muscle wasting, is a malignant metabolic syndrome with undefined etiology. Here, we show that both genetic ablation and pharmacological inhibition of TLR4 were able to attenuate the main clinical markers of cachexia in mice bearing Lewis lung carcinoma (LLC). AT remodelling was not found in LLC tumor-bearing (TB) TLR4^−/− mice due to reduced macrophage infiltration and adipocyte atrophy. TLR4^−/− mice were also resistant to cold-induced browning of subcutaneous AT (scAT). Importantly, pharmacological inhibition of TLR4 (Atorvastatin) reproduced the main protective effect against AT remodeling found in TLR4^−/− TB mice. Moreover, the treatment was effective in prolonging survival and attenuating tumor mass growth when compared to non-treated-TB animals. Furthermore, tumor-induced elevation of circulating pro-inflammatory cytokines was similarly abolished in both genetic ablation and pharmacological inhibition of TLR4. These data suggest that TLR4 is a critical mediator and a promising target for novel anti-cachexia therapies.

Hyperlipidemia, statin use and dengue severity

Multiple in vitro and mice model studies suggest statins may attenuate dengue severity. However, little is known about statin use and dengue severity in adult dengue patients with hyperlipidemia. We conducted a retrospective cohort study from 2004–2008 and 2012–2013 in Tan Tock Seng Hospital, Singapore on adult dengue patients with hyperlipidemia, comparing those with and without statin usage at hospitalization in terms of primary outcome of dengue hemorrhagic fever (DHF) or shock syndrome (DSS), and severe dengue (SD). Of 13,975 subjects screened, 257 dengue patients were included; 191 (74.3%) were statin users and 66 (25.7%) were non-users. Compared with non-users, statin use was not associated with decreased risk of DHF/DSS (adjusted risk ratio [aRR] = 0.66, 95%confidence interval [CI]: 0.41–1.08, P = 0.10) and SD (aRR = 1.43, 95%CI: 0.84–2.43, P = 0.19). Therefore, statin usage had minimal effect on dengue severity in our study population in Singapore.

Repurposing simvastatin as a therapy for preterm labor: evidence from preclinical models

Preterm birth (PTB), the leading cause of neonatal morbidity and mortality, urgently requires novel therapeutic agents. Spontaneous PTB, resulting from preterm labor, is commonly caused by intrauterine infection/inflammation. Statins are well-established, cholesterol-lowering drugs that can reduce inflammation and inhibit vascular smooth muscle contraction. We show that simvastatin reduced the incidence of PTB in a validated intrauterine LPS-induced PTB mouse model, decreased uterine proinflammatory mRNA concentrations (IL-6, Cxcl1, and Ccl2), and reduced serum IL-6 concentration. In human myometrial cells, simvastatin reduced proinflammatory mediator mRNA and protein expression (IL-6 and IL-8) and increased anti-inflammatory cytokine mRNA expression (IL-10 and IL-13). Critically, simvastatin inhibited myometrial cell contraction, basally and during inflammation, and reduced phosphorylated myosin light chain concentration. Supplementation with mevalonate and geranylgeranyl pyrophosphate, but not farnesyl pyrophosphate, abolished these anticontractile effects, indicating that the Rho/Rho-associated protein kinase pathway is critically involved. Thus, simvastatin reduces PTB incidence in mice, inhibits myometrial contractions, and exhibits key anti-inflammatory effects, providing a rationale for investigation into the repurposing of statins to treat preterm labor in women.—Boyle, A. K., Rinaldi, S. F., Rossi, A. G., Saunders, P. T. K., Norman, J. E. Repurposing simvastatin as a therapy for preterm labor: evidence from preclinical models.

Cytokines and statin therapy in chronic obstructive pulmonary disease patients

Cytokines are biological response modifiers involved in the pathophysiology of chronic obstructive pulmonary disease (COPD). This study investigated the potential use of cytokines as disease severity biomarkers in COPD patients and the possible effect of statin therapy on cytokine expression. Possible associations between cytokines, body mass index (BMI) and smoking have also been studied. Cytokines IFN-γ, IL-2, IL-12 p70, TNF-α, TNF-β, IL-4, IL-5, IL-6, IL-10, IL-1β and IL-8 were measured in the plasma of 100 clinically stable COPD patients using a fluorescent bead immunoassay on a flow cytometer. When patients were grouped according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage (A-D), no significant differences in cytokine concentrations were found (p > .05). Significantly decreased concentrations of IL-1β, IL-2, IL-4, IL-8, IL-10, IL-12p70 and TNF-α were found in COPD patients receiving statin therapy in comparison with COPD patients not receiving statin therapy (p < .05). COPD patients with increased BMI (>25) had decreased IL-2 (p=.038), IL-8 (p = .039) and IL-10 (p = .005) concentrations compared to normal BMI (20-25) patients. Current COPD smokers had increased concentrations of IL-5 (p = .037) compared to former COPD smokers. Hierarchical cluster analysis showed several patterns of measured cytokines in serum of patients with stable COPD. Statin therapy is associated with decreased expression of selected Th1 and Th2 cytokines in COPD, and this effect could be of relevance in COPD patients with increased cardiovascular risk. Concentrations of Th1 and Th2 cytokines in plasma cannot be used as biomarkers of disease severity or progression of COPD.

Interactions between dyslipidemia and the immune system and their relevance as putative therapeutic targets in atherosclerosis

Cardiovascular disease (CVD) continues to be a leading cause of death worldwide with atherosclerosis being the major underlying pathology. The interplay between lipids and immune cells is believed to be a driving force in the chronic inflammation of the arterial wall during atherogenesis. Atherosclerosis is initiated as lipid particles accumulate and become trapped in vessel walls. The subsequent immune response, involving both adaptive and immune cells, progresses plaque development, which may be exacerbated under dyslipidemic conditions. Broad evidence, especially from animal models, clearly demonstrates the effect of lipids on immune cells from their development in the bone marrow to their phenotypic switching in circulation. Interestingly, recent research has also shown a long-lasting epigenetic signature from lipids on immune cells. Traditionally, cardiovascular therapies have approached atherosclerosis through lipid-lowering medications because, until recently, anti-inflammatory therapies have been largely unsuccessful in clinical trials. However, the recent Canakinumab Antiinflammatory Thrombosis Outcomes Study (CANTOS) provided pivotal support of the inflammatory hypothesis of atherosclerosis in man spurring on anti-inflammatory strategies to treat atherosclerosis. In this review, we describe the interactions between lipids and immune cells along with their specific outcomes as well as discuss their future perspective as potential cardiovascular targets.

Innovations in asthma therapy: is there a role for inhaled statins?

INTRODUCTION

Asthma manifests as chronic airflow obstruction with persistent inflammation and airway hyperresponsiveness. The immunomodulatory and anti-inflammatory properties of the HMG-CoA reductase (HMGCR) inhibitors (a.k.a. statins), suggest a therapeutic role in chronic inflammatory lung diseases. However, despite positive laboratory investigations and promising epidemiological data, clinical trials using statins for the treatment of asthma have yielded conflicting results. Inadequate statin levels in the airway compartment could explain these findings. Areas covered: HMGCR is in the mevalonate (MA) pathway and MA signaling is fundamental to lung biology and asthma. This article will discuss clinical trials of oral statins in asthma, review lab investigations relevant to the systemic versus inhaled administration of statins, address the advantages and disadvantages of inhaled statins, and answer the question: is there a role for inhaled statins in the treatment of asthma? Expert commentary: If ongoing investigations show that oral administration of statins has no clear clinical benefits, then repurposing statins for delivery via inhalation is a logical next step. Inhalation of statins bypasses first-pass metabolism by the liver, and therefore, allows for delivery of significantly lower doses to the airways at greater potency. Statins could become the next major class of novel inhalers for the treatment of asthma.

RHOA GTPase Controls YAP-Mediated EREG Signaling in Small Intestinal Stem Cell Maintenance

RHOA, a founding member of the Rho GTPase family, is critical for actomyosin dynamics, polarity, and morphogenesis in response to developmental cues, mechanical stress, and inflammation. In murine small intestinal epithelium, inducible RHOA deletion causes a loss of epithelial polarity, with disrupted villi and crypt organization. In the intestinal crypts, RHOA deficiency results in reduced cell proliferation, increased apoptosis, and a loss of intestinal stem cells (ISCs) that mimic effects of radiation damage. Mechanistically, RHOA loss reduces YAP signaling of the Hippo pathway and affects YAP effector epiregulin (EREG) expression in the crypts. Expression of an active YAP (S112A) mutant rescues ISC marker expression, ISC regeneration, and ISC-associated Wnt signaling, but not defective epithelial polarity, in RhoA knockout mice, implicating YAP in RHOA-regulated ISC function. EREG treatment or active β-catenin Catnb^lox(ex3) mutant expression rescues the RhoA KO ISC phenotypes. Thus, RHOA controls YAP-EREG signaling to regulate intestinal homeostasis and ISC regeneration.

Statin therapy in patients with community-acquired pneumonia

Community-acquired pneumonia (CAP) is the leading cause of death from infection in developed countries. There is evidence of an association between improved survival from infection and statin use. The possible beneficial effects of statins are complicated by the common use of macrolide antibiotics for pneumonia, with current guidance suggesting that concurrent macrolide and statin use is contraindicated.We conducted an observational study of statin use in patients with CAP. Of 2,067 patients with CAP, 30.4% were on statin therapy at admission. Statin users were more likely to survive the admission (p<0.001). In addition, we conducted a survey of doctors and found that knowledge regarding concurrent macrolide and statin use was lacking.These data suggest a potential role of statins in the management of CAP. Further research using high-dose statins is required to assess their safe use in subjects with mild to moderate infections.

Cholesterol is required for stability and infectivity of influenza A and respiratory syncytial viruses

Cholesterol-rich lipid raft microdomains in the plasma membrane are considered to play a major role in the enveloped virus lifecycle. However, the functional role of cholesterol in assembly, infectivity and stability of respiratory RNA viruses is not fully understood. We previously reported that depletion of cellular cholesterol by cholesterol-reducing agents decreased production of human parainfluenza virus type 1 (hPIV1) particles by inhibiting virus assembly. In this study, we analyzed the role of cholesterol on influenza A virus (IAV) and respiratory syncytial virus (RSV) production. Unlike hPIV1, treatment of human airway cells with the agents did not decrease virus particle production. However, the released virions were less homogeneous in density and unstable. Addition of exogenous cholesterol to the released virions restored virus stability and infectivity. Collectively, these data indicate a critical role of cholesterol in maintaining IAV and RSV membrane structure that is essential for sustaining viral stability and infectivity.

Pravastatin and simvastatin inhibit the adhesion, replication and proliferation of Toxoplasma gondii (RH strain) in HeLa cells

The conventional treatment for toxoplasmosis with pyrimethamine and sulfadiazine shows toxic effects to the host, and it is therefore necessary to search for new drugs. Some studies suggest the use of statins, which inhibit cholesterol synthesis in humans and also the initial processes of isoprenoid biosynthesis in the parasite. Thus, the objective of this study was to evaluate the activity of the statins pravastatin and simvastatin in HeLa cells infected in vitro with the RH strain of T. gondii. HeLa cells (1×10⁵) were infected with T. gondii tachyzoites (5×10⁵) following two different treatment protocols. In the first protocol, T. gondii tachyzoites were pretreated with pravastatin (50 and 100μg/mL) and simvastatin (1.56 and 3.125μg/mL) for 30min prior to infection. In the second, HeLa cells were first infected (5×10⁵) with tachyzoites and subsequently treated with pravastatin and simvastatin for 24h at the concentrations noted above. Initially, we evaluated the cytotoxicity of drugs by the MTT assay, number of tachyzoites adhered to cells, number of infected cells, and viability of tachyzoites by trypan blue exclusion. The supernatant of the cell cultures was collected post-treatment for determination of the pattern of Th1/Th2/Th17 cytokines by cytometric bead array. There was no cytotoxicity to HeLa cells with 50 and 100μg/mL pravastatin and 1.56 and 3.125μg/mL simvastatin. There was no change in the viability of tachyzoites that received pretreatment. Regarding the pre- and post-treatment of the cells with pravastatin and simvastatin alone, there was a reduction in adhesion, invasion and proliferation of cells to T. gondii. As for the production of cytokines, we found that IL-6 and IL-17 were significantly reduced in cells infected with T. gondii and treated with pravastatin and simvastatin, when compared to control. Based on these results, we can infer that pravastatin and simvastatin alone possess antiproliferative effects on tachyzoites forms of T. gondii, giving these drugs new therapeutic uses.

Roles of the Mevalonate Pathway and Cholesterol Trafficking in Pulmonary Host Defense

The mevalonic acid synthesis pathway, cholesterol, and lipoproteins play fundamental roles in lung physiology and the innate immune response. Recent literature investigating roles for cholesterol synthesis and trafficking in host defense against respiratory infection was critically reviewed. The innate immune response and the cholesterol biosynthesis/trafficking network regulate one another, with important implications for pathogen invasion and host defense in the lung. The activation of pathogen recognition receptors and downstream cellular host defense functions are critically sensitive to cellular cholesterol. Conversely, microorganisms can co-opt the sterol/lipoprotein network in order to facilitate replication and evade immunity. Emerging literature suggests the potential for harnessing these insights towards therapeutic development. Given that >50% of adults in the U.S. have serum cholesterol abnormalities and pneumonia remains a leading cause of death, the potential impact of cholesterol on pulmonary host defense is of tremendous public health significance and warrants further mechanistic and translational investigation.

Association of medications for lifestyle-related diseases with reflux esophagitis

BACKGROUND

Because of a change in lifestyle, especially adoption of westernized eating habits, lifestyle-related diseases have become increasingly prevalent. The aim of this study was to investigate the association of medications for lifestyle-related diseases with reflux esophagitis (RE).

METHODS

We conducted a hospital-based, cross-sectional retrospective study of consecutive outpatients who received an upper gastrointestinal endoscopy in our department from February 2008 to November 2014, which was performed by one specialist who was a member of the Japan Gastroenterological Endoscopy Society. We investigated the patient profile, Helicobacter pylori (H. pylori) infection status, medications for lifestyle-related diseases (including calcium channel blockers, statins, and bisphosphonates), and upper gastrointestinal endoscopic findings (RE, hiatal hernia, Barrett's mucosa, and endoscopic gastric mucosal atrophy [EGA]). Patients with gastrectomy, peptic ulcer disease, gastric or esophageal malignant disease, and those who used proton pump inhibitors or histamine-2 receptor antagonists were excluded. We divided the subjects into a group without RE (RE(-)) and a RE (RE(+)) group as judged by endoscopy, and investigated the risk factors for RE.

RESULTS

Of 1,744 consecutive cases, 590 cases (300 males and 290 females; mean age 60.5±13.2 years) were eligible. RE(-) and RE(+) cases numbered 507 and 83, respectively. Bivariate analysis showed significant positive associations of RE with male sex, body mass index (BMI), calcium channel blockers, Barrett's mucosa, hiatal hernia and negative associations of RE with H. pylori positivity, EGA. Multivariate analysis showed significant positive associations of RE with BMI (odds ratio [OR]: 1.20, 95% confidence interval [95% CI]: 1.10-1.29), use of calcium channel blockers (OR: 2.12, 95% CI: 1.16-3.87), Barrett's mucosa (OR: 2.97, 95% CI: 01.64-5.38), hiatal hernia (OR: 3.13, 95% CI: 1.79-5.47) and negative associations of RE with H. pylori positivity (OR: 0.20, 95% CI: 0.07-0.57), use of statins (OR: 0.42, 95% CI: 0.18-0.96), and EGA (OR: 0.83, 95% CI: 0.70-0.98).

CONCLUSION

Calcium channel blockers were positively associated with RE and statins were negatively associated with RE, while bisphosphonates were not associated with RE.

A review of the effects of statins in systemic sclerosis

OBJECTIVES

We performed a literature review assessing possible benefits of statins in systemic sclerosis (SSc).

METHODS

PubMed, Embase, Cochrane Databases, and Medline were searched. Full-text English publications were identified in which the effects of statins in SSc were examined. Letters, review articles, and studies on morphea were excluded.

RESULTS

In all, 18 of 404 studies were relevant. In vitro, statins decreased transcription and translation of IL-6 and collagen, with reversal via mevalonate. Animal studies demonstrated reduced production of Ras (a protein superfamily of GTPases), Rho (part of the Ras superfamily), and extracellular signal-regulated kinases (ERK), less fibrosis and myofibroblast transdifferentiation, and improved macrovasculature. In human studies, IL-6, an inflammatory cytokine, was reduced. Usually endothelial progenitor cell concentrations increased, and flow-mediated dilatation improved. Raynaud's phenomenon, digital ulcers, and physician global assessments improved in the majority of studies of statin treatment in SSc. None of the 256 patients receiving statins experienced transaminitis or myopathy.

CONCLUSIONS

Not all findings were consistent. However, in general, in vitro, animal, and human studies demonstrated benefit in SSc pathophysiology, likely mediated through inhibition of lipid intermediate synthesis. Clinical improvement in SSc circulatory complications was observed. Statins seemed safe and well tolerated in SSc. Larger longer-term multi-site randomized trials are needed to further determine the role of statins as adjunctive treatment of this complex, heterogeneous connective tissue disease.

Intratracheal instillation of pravastatin for the treatment of murine allergic asthma: a lung-targeted approach to deliver statins

Systemic treatment with statins mitigates allergic airway inflammation, T_H2 cytokine production, epithelial mucus production, and airway hyperreactivity (AHR) in murine models of asthma. We hypothesized that pravastatin delivered intratracheally would be quantifiable in lung tissues using mass spectrometry, achieve high drug concentrations in the lung with minimal systemic absorption, and mitigate airway inflammation and structural changes induced by ovalbumin. Male BALB/c mice were sensitized to ovalbumin (OVA) over 4 weeks, then exposed to 1% OVA aerosol or filtered air (FA) over 2 weeks. Mice received intratracheal instillations of pravastatin before and after each OVA exposure (30 mg/kg). Ultra performance liquid chromatography – mass spectrometry was used to quantify plasma, lung, and bronchoalveolar lavage fluid (BALF) pravastatin concentration. Pravastatin was quantifiable in mouse plasma, lung tissue, and BALF (BALF > lung > plasma for OVA and FA groups). At these concentrations pravastatin inhibited airway goblet cell hyperplasia/metaplasia, and reduced BALF levels of cytokines TNFα and KC, but did not reduce BALF total leukocyte or eosinophil cell counts. While pravastatin did not mitigate AHR, it did inhibit airway hypersensitivity (AHS). In this proof-of-principle study, using novel mass spectrometry methods we show that pravastatin is quantifiable in tissues, achieves high levels in mouse lungs with minimal systemic absorption, and mitigates some pathological features of allergic asthma. Inhaled pravastatin may be beneficial for the treatment of asthma by having direct airway effects independent of a potent anti-inflammatory effect. Statins with greater lipophilicity may achieve better anti-inflammatory effects warranting further research.

Rosuvastatin improves hepatopulmonary syndrome through inhibition of inflammatory angiogenesis of lung. Clin Sci (Lond). 2015;129:449-460. [PMID: 25940601 DOI: 10.1042/cs20140622]

The hepatopulmonary syndrome (HPS) is characterized by hypoxia and increased intrapulmonary shunts in cirrhotic patients. Emerging evidence showed promising results of treating HPS by abolishment of intrapulmonary inflammation and angiogenesis. Rosuvastatin is a kind of 3-hydroxy-methyl-3-glutamyl coenzyme A reductase inhibitor. In addition to lipid-lowering effects, it has anti-inflammation and anti-angiogenesis properties. We postulated that rosuvastatin treatment can ameliorate HPS. Common bile duct ligation (CBDL) was applied in an experimental HPS animal model. CBDL rats received 2-week rosuvastatin (20 mg/kg/day) treatments from the fifteenth day after operation. The haemodynamic data, blood gas analysis, liver biochemistries, tumour necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF) were examined after rosuvastatin treatment. The liver and lung tissues were dissected for histopathological studies and protein analyses. In the parallel groups, intrapulmonary shunts were determined. The haemodynamic and liver biochemistries were not changed after rosuvastatin treatment in CBDL rats, but the alveolar-arterial oxygen pressure gradient was significantly decreased, implying that HPS-induced hypoxia was reversed after rosuvastatin treatment. In addition, rosuvastatin treatment reduced intrapulmonary shunts and plasma levels of VEGF and TNF-α. Besides, the intrapulmonary protein expression of nuclear factor kappa B (NF-κB), VEGF receptor (VEGFR)-1,2 and Rho-associated A kinase were significantly down-regulated and the intrapulmonary angiogenesis was ameliorated. We concluded that rosuvastatin alleviates experimental HPS through blockade of pulmonary inflammatory angiogenesis via TNF-α/NF-κB and VEGF/Rho-associated A kinase pathways down-regulation.

Novel applications of statins for bone regeneration

The use of statins for bone regeneration is a promising and growing area of research. Statins, originally developed to treat high cholesterol, are inhibitors of the enzyme 3-hydroxy-3-methylglutaryl, the rate-limiting enzyme of the mevalonate pathway. Because the mevalonate pathway is responsible for the synthesis of a wide variety of important biochemical molecules, including cholesterol and other isoprenoids, the effects of statins are pleiotropic. In particular, statins can greatly affect the process of bone turnover and regeneration via effects on important cell types, including mesenchymal stem cells, osteoblasts, endothelial cells, and osteoclasts. Statins have also been shown to have anti-inflammatory and antimicrobial properties that may be useful since infection can derail normal bone healing. This review will explore the pleiotropic effects of statins, discuss the current use of statins for bone regeneration, particularly with regard to biomaterials-based controlled delivery, and offer perspectives on the challenges and future directions of this emerging area of bone tissue engineering.

The impact of simvastatin on pulmonary effectors of Pseudomonas aeruginosa infection

The statin family of cholesterol-lowering drugs is known to have pleiotropic properties which include anti-inflammatory and immunomodulatory effects. Statins exert their pleiotropic effects by altering expression of human immune regulators including pro-inflammatory cytokines. Previously we found that statins modulate virulence phenotypes of the human pathogen Pseudomonas aeruginosa, and sought to investigate if simvastatin could alter the host response to this organism in lung epithelial cells. Simvastatin increased the expression of the P. aeruginosa target genes KLF2, KLF6, IL-8 and CCL20. Furthermore, both simvastatin and P. aeruginosa induced alternative splicing of KLF6. The novel effect of simvastatin on wtKLF6 expression was found to be responsible for induction of the KLF6 regulated genes CCL20 and iNOS. Simvastatin also increased the adhesion of P. aeruginosa to host cells, without altering invasion or cytotoxicity. This study demonstrated that simvastatin had several novel effects on the pulmonary cellular immune response.

Statins and asthma: where we stand, and the next critical steps in research

Asthma remains a formidable public health problem with ever increasing annual costs and prevalence. There are 300 million people with asthma worldwide. Per the Centers for Disease Control and Prevention, there are over 25 million Americans with asthma (both children and adults), i.e. one in 12 people have asthma, and this is increasing annually. Asthma results in approximately half a million hospitalizations and two million emergency department (ED) visits per year. In 2007 alone, 185 children and 3262 adults died from asthma, i.e. nine to ten patients die a day from asthma. This resulted in an annual cost of $56 billion in medical costs, lost work/school days, and early deaths. Therefore, we need novel and innovative therapies for asthma. In this Editorial, I review results from a study by Tse et al. evaluating the therapeutic potential of statins, within the context of our current state of knowledge. I review observational studies and clinical trials, highlight some potential pitfalls in clinical trial design, and discuss important questions for future research.

Statin use in asthmatics on inhaled corticosteroids is associated with decreased risk of emergency department visits

OBJECTIVE

Statins are hypothesized to have beneficial effects in asthma management through their pleiotropic anti-inflammatory effects. Several studies have examined this relationship, but have yielded conflicting results. This study investigates the effect of statin use on asthma-related hospitalizations and/or emergency department (ED) visits, and whether this relationship varies by concomitant inhaled corticosteroid (ICS) in a large cohort of asthma patients.

METHODS

Subjects with asthma, a recent history of asthma exacerbation, and who were 18 years or older were selected from the population-based Medco Health Solutions administrative database over a 1 year period. Prescription claims for statins and asthma medications, and asthma-related hospitalizations and/or ED visits were ascertained over a 12 month follow-up period. Subjects were stratified into two groups based on their ICS use.

RESULTS

A total of 3747 ICS users and 2905 non-ICS users were included in this study. Statin users represented 21% of ICS users and 11% of non-users. Among ICS users, statin use was significantly associated with decreased odds of asthma-related ED visits (OR = 0.77, 95% CI 0.64-0.94, p = 0.008), but not with asthma-related hospitalizations (OR = 1.09, 95% CI 0.92-1.30, p = 0.31). No significant associations were found among non-ICS users (for asthma-related ED visits: OR = 0.92, 95% CI 0.57-1.49, p = 0.73; asthma-related hospitalizations: OR = 1.10, 95% CI 0.85-1.41, p = 0.48). The statistical interactions between ICS and statin use on asthma-related hospitalizations and/or ED visits were not significant.

CONCLUSION

Statin use is associated with fewer ED visits in asthma patients who are using ICS.

The pleiotropic effects of the hydroxy-methyl-glutaryl-CoA reductase inhibitors in renal disease

It is well known that statins exert their main effect by inhibiting cholesterol synthesis through the inhibition of the 3-hydroxy-3-methyl-glutaryl-CoA reductase enzyme. The pleiotropic effects of statins, which are independent of their inhibition of cholesterol synthesis, have explained many of the beneficial effects of these drugs in a variety of disorders such as malignancies, infection, and sepsis, as well as in cardiovascular and rheumatologic disorders. However, the role of these drugs in renal disorders remains controversial. In the present review, we examine the most recent findings involving statins and renal disease among different clinical scenarios, including chronic kidney disease, contrast-induced nephropathy, renal injury after coronary artery bypass surgery, and renal transplant patients.

Targeting the mevalonate cascade as a new therapeutic approach in heart disease, cancer and pulmonary disease

The cholesterol biosynthesis pathway, also known as the mevalonate (MVA) pathway, is an essential cellular pathway that is involved in diverse cell functions. The enzyme 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase (HMGCR) is the rate-limiting step in cholesterol biosynthesis and catalyzes the conversion of HMG-CoA to MVA. Given its role in cholesterol and isoprenoid biosynthesis, the regulation of HMGCR has been intensely investigated. Because all cells require a steady supply of MVA, both the sterol (i.e. cholesterol) and non-sterol (i.e. isoprenoid) products of MVA metabolism exert coordinated feedback regulation on HMGCR through different mechanisms. The proper functioning of HMGCR as the proximal enzyme in the MVA pathway is essential under both normal physiologic conditions and in many diseases given its role in cell cycle pathways and cell proliferation, cholesterol biosynthesis and metabolism, cell cytoskeletal dynamics and stability, cell membrane structure and fluidity, mitochondrial function, proliferation, and cell fate. The blockbuster statin drugs ('statins') directly bind to and inhibit HMGCR, and their use for the past thirty years has revolutionized the treatment of hypercholesterolemia and cardiovascular diseases, in particular coronary heart disease. Initially thought to exert their effects through cholesterol reduction, recent evidence indicates that statins also have pleiotropic immunomodulatory properties independent of cholesterol lowering. In this review we will focus on the therapeutic applications and mechanisms involved in the MVA cascade including Rho GTPase and Rho kinase (ROCK) signaling, statin inhibition of HMGCR, geranylgeranyltransferase (GGTase) inhibition, and farnesyltransferase (FTase) inhibition in cardiovascular disease, pulmonary diseases (e.g. asthma and chronic obstructive pulmonary disease (COPD)), and cancer.

Inhibitory effects of pitavastatin on fibrogenic mediator production by human lung fibroblasts

AIMS

Idiopathic pulmonary fibrosis continues to be a devastating clinical disorder for which there are few therapeutic options, and the pathogenesis of this disease remains largely unknown. Statins are inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase in cholesterol biosynthesis, and they have been reported to exert pleiotropic effects on the cellular signaling involved in tissue inflammation and in organ fibrosis/remodeling. We examined the preventive effects of statins on fibrogenic mediator expression and production in normal human lung fibroblasts (NHLF).

MAIN METHODS

NHLF were pretreated with 100nM pitavastatin or medium alone (control), and were then stimulated with transforming growth factor-β1 (TGF-β1). mRNA expression and protein secretion of several mediators from cells were analyzed by real-time polymerase chain reaction, enzyme-linked immunosorbent assay or multiplex assay.

KEY FINDINGS

TGF-β1-induced expression or production of mediators, such as collagen-1, vascular endothelial growth factor and chemokine C-X-C motif ligand 8, in NHLF pretreated with pitavastatin was significantly suppressed with inhibition of Smad-3 phosphorylation, as compared to untreated controls. In addition, the inhibitory effects of pitavastatin were negated by addition of mevalonate.

SIGNIFICANCE

Pitavastatin appeared to inhibit TGF-β1-induced fibrogenic mediator production from lung fibroblasts via the mevalonic cascade. Although further evaluation of the signaling pathways for these phenomena is necessary, our results suggest the potential benefits of pitavastatin.

Statin use and asthma control in patients with severe asthma

OBJECTIVES

We hypothesised that severe asthmatics taking a statin drug, in addition to inhaled corticosteroids/long-acting β-agonist inhaler therapy, would have better asthma symptom control and improved lung function compared to their controls.

STUDY DESIGN

A retrospective, cross-sectional study of 165 patients with severe asthma seen from 2001-2008. Hierarchical linear and logistic regression models were used for modelling fitting.

SETTING

University of California, Davis Medical Center (Sacramento, California, USA). Academic, single-centre, severe asthma subspecialty clinic.

PARTICIPANTS

612 screened, 223 eligible and 165 adult patients were included in the final study (N=165; 31 statin users and 134 non-users).

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary endpoint was asthma control as measured by the Asthma Control Test (ACT). The secondary endpoints included lung function, symptoms and the need for corticosteroid burst and peripheral eosinophil count.

RESULTS

At baseline, statin users compared to non-users were older, had lower lung function (FEV1% predicted, FEV1, forced vital capacity and FEF25-75%) and had a higher prevalence of comorbid conditions. Statin use was associated with more aspirin and ipratropium inhaler use than in non-users. Patients in both groups were obese (body mass index ≥ 30). Statin users had better asthma symptom control compared to non-users (higher adjusted mean ACT score by 2.2±0.94 points, p<0.02). Median statin use was for 1 year. There were no statistically significant differences in lung function, corticosteroid or rescue bronchodilator use or peripheral eosinophilia between the two groups.

CONCLUSIONS

In our severe asthma referral population, statin users already taking inhaled controller therapy achieved better asthma control compared to non-users. The implications of this study is that patients with severe asthma could potentially benefit from added statin treatment. Because our study population was on average obese, the obese severe asthmatic may be a viable asthma subphenotype for further studies. Prospective randomised clinical trials evaluating the safety and efficacy of statins in severe asthma are warranted.

Redox markers and inflammation are differentially affected by atorvastatin, pravastatin or simvastatin administered before endotoxin-induced acute lung injury

Statins are standard therapy for the treatment of lipid disorders, and the field of redox biology accepts that statins have antioxidant properties. Our aim in this report was to consider the pleiotropic effects of atorvastatin, pravastatin and simvastatin administered prior to endotoxin-induced acute lung injury. Male mice were divided into 5 groups and intraperitoneally injected with LPS (10 mg/kg), LPS plus atorvastatin (10 mg/kg/day; A + LPS group), LPS plus pravastatin (5 mg/kg/day; P + LPS group) or LPS plus simvastatin (20 mg/kg/day; S + LPS group). The control group received saline. All mice were sacrificed one day later. There were fewer leukocytes in the P + LPS and S + LPS groups than in the LPS group. MCP-1 cytokine levels were lower in the P + LPS group, while IL-6 levels were lower in the P + LPS and S + LPS groups. TNF-α was lower in all statin-treated groups. Levels of redox markers (superoxide dismutase and catalase) were lower in the A + LPS group (p < 0.01). The extent of lipid peroxidation (malondialdehyde and hydroperoxides) was reduced in all statin-treated groups (p < 0.05). Myeloperoxidase was lower in the P + LPS group (p < 0.01). Elastance levels were significantly greater in the LPS group compared to the statin groups. Our results suggest that atorvastatin and pravastatin but not simvastatin exhibit anti-inflammatory and antioxidant activity in endotoxin-induced acute lung injury.

Simvastatin treatment ameliorates injury of rat testes induced by cadmium toxicity

Cadmium-induced testicular toxicity is mediated through oxidative stress and inflammation which eventually lead to cell death. Simvastatin, the antihyperlipidemic agent, exhibits additional antioxidant and anti-inflammatory activities. The aim of the present work was to investigate the protective effect of simvastatin against cadmium-induced testicular toxicity in rats. The rats received a single intraperitoneal (i.p.) injection of cadmium chloride (2 mg/kg). Simvastatin treatment (5 mg/kg/day, i.p.) was applied for three consecutive days, starting 1 day before cadmium administration. Cadmium significantly decreased serum testosterone, and testicular reduced glutathione and catalase activity, and significantly increased testicular malondialdehyde, nitric oxide, and cadmium ion levels. Simvastatin significantly ameliorated the biochemical changes induced by cadmium. Cadmium-induced testicular tissue injury observed by histopathological examination was attenuated by simvastatin. In addition, simvastatin significantly decreased the expression of inducible nitric oxide synthase, cyclooxygenase-2, tumor necrosis factor-α, nuclear factor-κB, and caspase-3, and increased heme oxygenase-1 expression in testicular tissue of rats exposed to cadmium toxicity. It was concluded that simvastatin, through its antioxidant and anti-inflammatory activities, provided a significant protective effect against cadmium-induced testicular toxicity in rats. However, starting treatment with simvastatin before cadmium exposure, as done in the present work, is not clinically applicable. Therefore, other investigations are needed to assess the protective effect of simvastatin treatment following induction of cadmium testicular toxicity.

The immunomodulatory effects of statins in community-acquired pneumonia: a systematic review

OBJECTIVE

To evaluate the potential immunomodulatory effects of statins in community-acquired pneumonia.

METHODS

We performed a systematic review of available literature on experimental and clinical studies. We used a PubMed/MEDLINE and EMBASE search to identify potential articles.

RESULTS

We identified 34 original studies, 17 experimental and 17 clinical studies, published up to March 2013.

CONCLUSIONS

Statins attenuated pulmonary inflammation by modulating neutrophil function, by reducing cytokine expression and release, and by protecting against disruption of pulmonary integrity. However, additional experimental studies are needed to fully elucidate the exact mechanisms. Several clinical studies suggested a decreased risk of CAP or a reduction in mortality due to CAP for current statin users, but the mostly observational design of these studies hampers the interpretation of their results. Therefore, appropriately designed studies, such as randomised controlled trials, are required to demonstrate the usefulness of statins in the prevention and treatment of CAP.

Atorvastatin inhibits RhoC function and limits head and neck cancer metastasis

OBJECTIVE

RhoC oncogene is a well characterized marker of metastasis in a majority of invasive cancers, including HNSCC. Elevated RhoC expression has been found to be associated with distant metastasis. Statins are a class of drugs that are used to reduce cholesterol levels by inhibiting HMG-CoA reductase activity which in turns prevents mevalonate synthesis, which is a precursor for synthesis of cholesterol and prenylation. Interestingly, the proper function of Rho proteins depends on prenylation. Significantly, it has been reported that metastasis in human melanoma can be reduced by atorvastatin which inhibits RhoC activity by preventing its geranylgeranylation. Given that RhoC is a key oncogene involved in metastasis, we hypothesized Atorvastatin can reduce head and neck metastasis by inhibiting RhoC activity.

METHODS

In vitro and in vivo studies were carried out to evaluate the ability of Atorvastatin to inhibit RhoC function and HNSCC metastasis. Cell motility, proliferation, cell invasion, and colony formation assays were performed according to the standard protocols.

RESULTS

Atorvastatin treatment significantly reduced the active form of RhoC in vitro and diminished cell motility, invasion, proliferation and colony formation. Importantly, we observed a significant decrease in p-ERK1/2 and p-STAT3 in Atorvastatin treated cell lines. In vivo experiments revealed inhibition of angiogenesis and lung metastases with Atorvastatin therapy.

CONCLUSIONS

This study is the first of its kind to establish a potential role of Atorvastatin in head and neck cancer therapy. These findings suggest that Atorvastatin can be a potential low risk adjuvant therapy to minimize metastases in aggressive forms of HNSCC.

Chromatin remodeling by rosuvastatin normalizes TSC2-/meth cell phenotype through the expression of tuberin

Tuberous sclerosis complex (TSC) is a multi-systemic syndrome caused by mutations in TSC1 or TSC2 gene. In TSC2-null cells, Rheb, a member of the Ras family of GTPases, is constitutively activated. Statins inhibit 3-hydroxy-3-methylglutaryl coenzyme A reductase and block the synthesis of isoprenoid lipids with inhibition of Rheb farnesylation and RhoA geranylgeranylation. The effects of rosuvastatin on the function of human TSC2(-/-) and TSC2(-/meth) α-actin smooth muscle (ASM) cells have been investigated. The TSC2(-/-) and TSC2(-/meth) ASM cells, previously isolated in our laboratory from the renal angiomyolipoma of two TSC patients, do not express tuberin and bear loss of heterozigosity caused by a double hit on TSC2 and methylation of TSC2 promoter, respectively. Exposure to rosuvastatin affected TSC2(-/meth) ASM cell growth and promoted tuberin expression by acting as a demethylating agent. This occurred without changes in interleukin release. Rosuvastatin also reduced RhoA activation in TSC2(-/meth) ASM cells, and it required coadministration with the specific mTOR (mammalian target of rapamycin) inhibitor rapamycin to be effective in TSC2(-/-) ASM cells. Rapamycin enhanced rosuvastatin effect in inhibiting cell proliferation in TSC2(-/-) and TSC2(-/meth) ASM cells. Rosuvastatin alone did not alter phosphorylation of S6 and extracellular signal-regulated kinase (ERK), and at the higher concentration, rosuvastatin and rapamycin slightly decreased ERK phosphorylation. These results suggest that rosuvastatin may potentially represent a treatment adjunct to the therapy with mTOR inhibitors now in clinical development for TSC. In particular, rosuvastatin appears useful when the disease is originated by epigenetic defects.

HMG-CoA Reductase Inhibitors for Prevention and Treatment of Severe Sepsis

HMG-CoA reductase inhibitors, or statins, are among the most commonly prescribed pharmaceuticals in the world, especially among the elderly. The remarkable conjuncture of this fact with the rising incidence of severe sepsis among people over age 65 could prove to be of serendipitous benefit, because numerous actions of the statins make them of potential use in the prevention and treatment of severe sepsis. Severe sepsis continues to be a highly lethal condition, for which there are, as yet, no effective pharmacological treatments, save antibiotics. We explore the biological plausibility of statins as prophylaxis agents and as treatment for severe sepsis and thoroughly review the preclinical and clinical studies that have explored the effects of statins in infected and septic patients. Statins remain only promising treatments for severe sepsis, without convincing evidence that they reduce patient mortality. Ongoing randomized trials may provide conclusive evidence, whether positive or negative.