Statins in therapy: Understanding their hydrophilicity, lipophilicity, binding to 3-hydroxy-3-methylglutaryl-CoA reductase, ability to cross the blood brain barrier and metabolic stability based on electrostatic molecular orbital studies

Statin use, hyperlipidemia, and risk of glioma

Background Statins have previously been shown to have protective effects for other cancers, but no prospective studies of statin use and glioma have been conducted. Methods We evaluated the association between statin use and risk of glioma in the female Nurses' Health Study (NHS, n = 114,419) and Nurses' Health Study II (NHSII, n = 115,813) and the male Health Professionals Follow-up Study (HPFS, n = 50,223). Glioma cases were confirmed by medical record review. Age and multivariable-adjusted hazard ratios of glioma by statin use were estimated using Cox proportional hazards models. Results In 4,430,700 person-years of follow-up, we confirmed 483 incident cases of glioma. Compared with never-users, ever statin use was associated with borderline increased risk of glioma in the combined cohorts (age-adjusted HR = 1.23, 95% CI 0.99-1.54), as was longer duration of statin use (HR = 1.48, 95% CI 1.08-2.03 comparing > 8 years of use to never use, p-trend = 0.01). We also observed a significant inverse association between hyperlipidemia and glioma in multivariable models (HR = 0.74, 95% CI 0.59-0.93 in combined cohorts), which was attenuated in lagged analyses. Compared to never use, in multivariable-adjusted models, ever statin use (HR = 1.43, 95% CI 1.10-1.86) and statin use duration (HR = 1.72, 95% CI 1.21-2.45, for > 8 years of use, p-trend = 0.003) were each significantly associated with increased glioma risk. Conclusion In contrast to case-control studies reporting inverse associations, we found borderline increased risk of glioma with statin use. Results were strengthened after adjustment for cardiovascular risk factors due to an unexpected inverse association between hyperlipidemia and glioma risk. Further studies of statin use, hyperlipidemia, and glioma risk are warranted.

Cataracts and statins. A disproportionality analysis using data from VigiBase

The basis of the association between statin use and cataract has been explored using the World Health Organization (WHO) global database of individual case safety reports (ICSRs) for drug monitoring (VigiBase) through January 2019. The reporting odds ratios (RORs) as a measure of disproportionality for reported cataracts and individual statins have been calculated. Subgroup analyses according statin lipophilicity, sex, and age groups have been performed. Moreover, RORs have been calculated for non-statin lipid lowering drugs. An increased disproportionality have been found for most individual statins lovastatin: [ROR: 14.80, 95% confidence interval (CI): 13.30, 16.46)], atorvastatin (ROR: 3.48, 95% CI 3.19-3.80), pravastatin (ROR: 3.15, 95% CI: 2.54-3.90), rosuvastatin (ROR: 2.90, 95% CI: 2.53-3.31), simvastatin (ROR: 2.27, 95%CI: 1.99-2.60), fluvastatin (ROR: 2.03, 95% CI: 1.33-3.08) and statins (overall) ROR: 3.66, 95% CI:3.46-3.86). Increased disproportionality for cataract and statins (drug-class) have been found regardless of statin lipophilicity, sex and group age (more or less than 65 years old). No disproportionality was found for other lipid-lowering drugs (ezetimibe, fibrates or PCSK9 inhibitors). These findings suggest an increased risk of cataract associated with statins as a drug-class. Further studies to characterize the risk are advised. Benefits and potential harms should be considered before starting treatment with statins.

Clinically relevant drug interactions between statins and antidepressants

WHAT IS KNOWN AND OBJECTIVE

Statins, also known as 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors, and antidepressant drugs are frequently used in combination due to the high and growing incidence of cardiovascular diseases and psychiatric disorders worldwide. Several aspects on management, the risk of adverse events (AEs) occurrence and the potential clinically relevant pharmacokinetic (PK) and pharmacodynamic (PD) drug-drug interactions (DDIs) between these two classes have not been well investigated. The aim of the present review was to describe the PK and PD interactions, of clinical relevance, between statins and antidepressant drugs and provide a comprehensive overview of their pharmacological features for appropriate multiple drug regimens.

METHODS

Relevant studies were identified through a literature search of PubMed and the Cochrane databases focusing on clinically relevant DDIs between statins and antidepressants. Only papers in English were included in the search.

RESULTS AND DISCUSSION

Pharmacodynamic (PD) drug-drug interactions (DDIs) are unlikely to occur as statins are highly selective inhibitors of HMG-CoA reductase with no relevant effect on other enzymes or receptor systems. Despite the numerous PK studies on individual drugs belonging to statins and antidepressant agents, only a few case reports regarding specific DDIs are present in the literature and no clinical studies have been performed. PK data allow to speculate on potential DDIs, comparing the metabolic pathways, intestinal and liver transporters and elimination routes. Overall, second-generation antidepressants, in particular citalopram, escitalopram, mirtazapine, reboxetine and venlafaxine, have weak inhibitory effects on various cytochrome (CYP) isozymes and seem to have a more advantageous DDIs profile in vivo. Conversely, nefazodone, fluoxetine, paroxetine and fluvoxamine influence considerably CYPs activity with potential effects on statins plasma levels, although pravastatin, pitavastatin and rosuvastatin are not susceptible to inhibition by any CYP. Albeit no studies have been performed on P-glycoprotein (P-gp), interactions of clinical relevance are unlikely.

WHAT IS NEW AND CONCLUSION

Although DDIs with antidepressants are potentially, but rarely clinically significant, the use of antidepressants with a more favourable drug interaction profile is advisable. An evaluation on DDIs between these drugs can be useful for future PK/PD studies on drug-drug interaction to provide clinicians with more data for appropriate multiple drug regimens.

Biodegradable polymerized simvastatin stimulates bone formation

Previous research from our labs demonstrated the synthesis of polymerized simvastatin by ring-opening polymerization and slow degradation with controlled release of simvastatin in vitro. The objective of the present study was to evaluate the degradation and intramembranous bone-forming potential of simvastatin-containing polyprodrugs in vivo using a rat calvarial onlay model. Poly(ethylene glycol)-block-poly(simvastatin) and poly(ethylene glycol)-block-poly(simvastatin)-ran-poly(glycolide) were compared with simvastatin conventionally encapsulated in poly(lactic-co-glycolic acid) (PLGA) and pure PLGA. The rate of degradation was higher for PLGA with and without simvastatin relative to the simvastatin polyprodrugs. Significant new bone growth at the circumference of poly(ethylene glycol)-block-poly(simvastatin) disks was observed beginning at 4 weeks, whereas severe bone resorption (4 weeks) and bone loss (8 weeks) were observed for PLGA loaded with simvastatin. No significant systemic effects were observed for serum total cholesterol and body weight. Increased expression of osteogenic (BMP-2, Runx2, and ALP), angiogenic (VEGF), and inflammatory cytokines (IL-6 and NF-ĸB) genes was seen with all polymers at the end of 8 weeks. Poly(ethylene glycol)-block-poly(simvastatin), with slow degradation and drug release, controlled inflammation, and significant osteogenic effect, is a candidate for use in bone regeneration applications. STATEMENT OF SIGNIFICANCE: Traditional drug delivery systems, e.g., drug encapsulated in poly(lactic-co-glycolic acid) (PLGA), are typically passive and have limited drug payload. As an alternative, we polymerized the drug simvastatin, which has multiple physiological effects, into macromolecules ("polysimvastatin") via ring-opening polymerization. We previously demonstrated that the rate of degradation and drug (simvastatin) release can be adjusted by copolymerizing it with other monomers. The present results demonstrate significant new bone growth around polysimvastatin, whereas severe bone loss occurred for PLGA loaded with simvastatin. This degradable biomaterial with biofunctionality integrated into the polymeric backbone is a useful candidate for bone regeneration applications.

Effect of initiating statin therapy on long-term outcomes of patients with dyslipidemia after intracerebral hemorrhage

BACKGROUND AND AIMS

Intracerebral hemorrhage (ICH) has a higher mortality than ischemic stroke. Statin is beneficial for stroke, but high potency statin treatment has been associated with the risk of hemorrhagic stroke. The aim of this study was to assess the impact of initiating statin therapy after ICH on cardiovascular outcomes.

METHODS

Dyslipidemic patients were retrieved from the ICH population from the National Health Insurance Research Database in Taiwan. We retrospectively compared patients prescribed with and without statin treatment after ICH. Outcomes of interest were mortality, myocardial infarction, ischemic stroke, and hemorrhagic stroke during 5 years of follow-up.

RESULTS

Of 17,980 adult patients with ICH and dyslipidemia, 8927 were eligible for analysis over the study period, including 1613 patients receiving statin therapy and 7314 patients not taking statins. After propensity score matching, the mean age was 61.2 ± 12.2 years in the statin group and 61.6 ± 13.0 years in the non-statin group. Hypertension was dominant, followed by diabetes mellitus, and the mean estimated NIHSS score was 12.9. The patients who received statin therapy were associated with lower risks of all-cause mortality (12.7% vs. 21.3%; hazard ratio [HR], 0.54; 95% confidence interval [CI], 0.45-0.65), cardiovascular death (4.0% vs. 7.1%; HR, 0.54; 95% CI, 0.39-0.75) and ICH (5.4% vs. 8.5%; HR, 0.62; 95% CI, 0.46-0.83) compared to those who did not receive statins.

CONCLUSIONS

Initiating statin therapy after ICH was associated with a decreased risk of recurrent ICH and mortality for dyslipidemia patients.

Contribution of Statins towards Periodontal Treatment: A Review

The pleiotropic effects of statins have been evaluated to assess their potential benefit in the treatment of various inflammatory and immune-mediated diseases including periodontitis. Herein, the adjunctive use of statins in periodontal therapy in vitro, in vivo, and in clinical trials was reviewed. Statins act through several pathways to modulate inflammation, immune response, bone metabolism, and bacterial clearance. They control periodontal inflammation through inhibition of proinflammatory cytokines and promotion of anti-inflammatory and/or proresolution molecule release, mainly, through the ERK, MAPK, PI3-Akt, and NF-κB pathways. Moreover, they are able to modulate the host response activated by bacterial challenge, to prevent inflammation-mediated bone resorption and to promote bone formation. Furthermore, they reduce bacterial growth, disrupt bacterial membrane stability, and increase bacterial clearance, thus averting the exacerbation of infection. Local statin delivery as adjunct to both nonsurgical and surgical periodontal therapies results in better periodontal treatment outcomes compared to systemic delivery. Moreover, combination of statin therapy with other regenerative agents improves periodontal healing response. Therefore, statins could be proposed as a potential adjuvant to periodontal therapy. However, optimization of the combination of their dose, type, and carrier could be instrumental in achieving the best treatment response.

Lipophilic statins inhibit growth and reduce invasiveness of human endometrial stromal cells

PURPOSE

To compare effects of lipid-soluble statins (simvastatin, lovastatin, atorvastatin) and water-soluble statin (pravastatin) on growth and invasiveness of human endometrial stromal (HES) cells.

METHODS

Endometrial biopsies were collected during the proliferative phase from five volunteers. HES cells were isolated and cultured in the absence or in the presence of simvastatin, lovastatin, atorvastatin, and pravastatin. Effects of statins on DNA synthesis, cell viability, activity of caspases 3/7 and invasiveness were evaluated.

RESULTS

The proliferation of HES cells was significantly decreased by simvastatin (by 47-89%), lovastatin (by 46-78%), and atorvastatin (by 21-48%) in a concentration-dependent manner. Activity of executioner caspases 3/7 was significantly increased by simvastatin (by 10-25%), lovastatin (by 19%) and atorvastatin (by 7-10%) in a concentration-dependent manner. The greatest effects were observed in response to simvastatin. Accounting for the effects of statins on cell number, the invasiveness of HES cells was significantly decreased in cells treated with simvastatin (by 49%), lovastatin (by 54%), and atorvastatin (by 53%). Pravastatin had little or no effects on any of the tested endpoints.

CONCLUSIONS

Present findings demonstrate that only lipid-soluble among tested statins were effective in inhibition of growth and invasiveness of HES cells. These findings may have clinical relevance in treatment of endometriosis.

Statin therapy and association with ovarian cancer risk in the New England Case Control (NEC) study

Statins are widely used to lower blood cholesterol and reduce risk for cardiovascular diseases, but attention has recently focused on a role in cancer prevention or therapy. Here we present data from a large case-control study addressing whether statin use can lower the risk for epithelial ovarian cancer (EOC). Between 1992 and 2008, data including medications used for at least 6 months were collected from 2,040 cases with EOC and 2,100 frequency-matched controls without the disease who participated in the New England Case Control study. We used unconditional logistic regression controlling for matching factors and potential confounders to examine the association between statin use and the risk for EOC. Overall, women who used statins had 32% lower risk of ovarian cancer compared to non-users (Odds ratio (OR) 0.68, 95% Confidence Interval (CI): 0.54-0.85), adjusting for the matching factors and other covariates. The reduced risk was most apparent in women taking a lipophilic statin who began use after age 49, and who had used them 2-4.9 years. Statin use was associated with lower risks for both serous and non-serous histologic subtypes with the strongest effect seen for mucinous and mixed epithelial subtypes. The association became apparent about a decade after the introduction of statins and did not appear to be confounded by indications for use of statins or medications used concomitantly. In this case-control study, statins were found to lower the risk for both serous and non-serous EOC and especially mucinous EOC.

Comparative risk of lipophilic and hydrophilic statins on incident depression: A retrospective cohort study

OBJECTIVES

To evaluate the risk of new-onset depression in a cohort of US adult patients initiating lipophilic statin therapy compared to hydrophilic statin therapy.

DESIGN

Retrospective cohort study.

SETTING

Large US commercial claims database PARTICIPANTS: 1:1 propensity score matched cohort of lipophilic (atorvastatin, lovastatin and simvastatin) and hydrophilic (pravastatin and rosuvastatin) statin initiators between January 2009 to June 2015.

OUTCOME

New onset of depression.

RESULTS

In a propensity-score matched cohort of 299,298 statin initiators, the crude incidence of depression in the hydrophilic and lipophilic group was 136.6 and 142.8 per 10,000 person-years respectively. Compared to hydrophilic statin use, lipophilic statin use was not associated with a statistically significant increase in the risk of depression, adjusted HR 1.05 (95% CI, 1.00-1.10, p = 0.078) and excess incidence of 6.3 (95% CI, -0.7-13.7) per 10,000 person-years. Findings were consistent across the subgroups of patients with history of psychiatric conditions HR 1.05 (95% CI, 0.94-1.16, p = 0.41), and those initiating statins for primary or secondary prevention, HR 1.03 (95% CI, 0.97-1.10, p = 0.33) and 1.07 (95% CI, 0.99-1.16, p = 0.10) respectively. Within individual lipophilic statins, only simvastatin was associated with a moderate increase in the risk of depression HR 1.09 (95% CI, 1.02-1.16, p = 0.003), followed by lovastatin HR 1.07 (95% CI, 0.93-1.24, p = 0.34) and atorvastatin HR 1.05 (95% CI, 0.97-1.13, p = 0.27).

LIMITATIONS

Findings are generalizable to patients with commercial insurance.

CONCLUSIONS

Lipophilic statin use was not associated with a significant increase in the risk of incident depression.

Immunotropic Effects and Proposed Mechanism of Action for 3-Hydroxy-3-methylglutaryl-coenzyme A Reductase Inhibitors (Statins)

Inhibitors of HMG-CoA reductase (statins) are the major group of lipid-lowering drugs. Along with hypocholesterolemic activity, statins exhibit anti-inflammatory and immunomodulatory properties that expand their clinical use, particularly, in the treatment of chronic inflammatory and autoimmune disorders. In this review, we critically analyze the data of statin effects on immune cells (e.g., monocytes and T cells) involved in the development of atherosclerosis and other chronic inflammatory diseases. We (i) discuss the properties of statins and routes of cell entry, as well as their major intracellular targets; (ii) evaluate the data on the effects of statins on the subset composition of circulatory monocytes, ability of monocytes to migrate to the site of inflammation (cell motility and expression of adhesion molecules and chemokine receptors), production of cytokines, matrix metalloproteinases, and reactive oxygen species by monocytes/macrophages, and antigen-presenting activity in peripheral blood monocyte-derived dendritic cells; and (iii) summarize the data on the regulation of proliferation and differentiation of various CD4+ T cell subsets (type 1/2/17 helper T cells and regulatory T cells) by statins.

ADME properties evaluation in drug discovery: in silico prediction of blood-brain partitioning

The absorption, distribution, metabolism and excretion properties are important for drugs, and prediction of these properties in advance will save the cost of drug discovery substantially. The ability to penetrate the blood-brain barrier is critical for drugs targeting central nervous system, which is represented by the ratio of its concentration in brain and in blood. Herein, a quantitative structure-property relationship study was carried out to predict blood-brain partitioning coefficient (logBB) of a data set consisting of 287 compounds. Four different methods including support vector machine, multivariate linear regression, multivariate adaptive regression splines and random forest were employed to build prediction models with 116 molecular descriptors selected by Boruta algorithm. The RF model had best performance in training set ([Formula: see text] = 0.938), test set ([Formula: see text] = 0.840) and tenfold cross-validation ([Formula: see text] = 0.788). Finally, we found that the polar surface area and octanol-water partition coefficient have the greatest influence on blood-brain partitioning. Results suggest that the proposed model is a useful and practical tool to predict the logBB values of drug candidates.

An update on efflux and uptake transporters as determinants of statin response

INTRODUCTION

Statins are used in the treatment of dyslipidemia promoting primary and secondary prevention against detrimental cardiovascular events. ATP-binding cassette (ABC) and solute carrier (SLC) membrane transporters transport statins across the cell membrane. Differences in drug transporter tissue expression and activity contribute to variability in statin pharmacokinetics (PK) and response. Areas covered: The purpose of this review is to discuss factors impacting transporter expression and the effect this has on statin efficacy and safety. Previous studies have demonstrated that genetic polymorphisms, drug-drug interactions (DDI), nuclear receptors, and microRNAs affect statin PK and pharmacodynamics. Expert opinion: Genetic variants of ABCG2 and SLCO1B1 transporters affect statin PK and, as a result, the intended lipid-lowering response. However, the effect size is small, limiting its applicability in clinical practice. Furthermore, genetic variants do not totally explain the observed intervariability in statin response. Thus, it is likely that transcriptional and post-transcriptional regulation of drug transporters are also highly involved. Further studies are required to understand the contribution of each of these new factors in statin disposition and toxicity.

An analysis of the effect of statins on the risk of Non-Hodgkin's Lymphoma in the Women's Health Initiative cohort

Statins have been shown to induce a phosphoprotein signature that modifies MYC (myelocytomatosis viral oncogene) activation and to have anti‐inflammatory activity that may impact the risk of Non‐Hodgkin's lymphoma (NHL). We analyzed the relationship between statins and risk of NHL using data from the Women's Health Initiative (WHI). The study population included 161,563 postmenopausal women ages 50–79 years from which 712 cases of NHL were diagnosed after 10.8 years of follow‐up. Information on statin use and other risk factors was collected by self‐ and interviewer‐administered questionnaires. Multivariable‐adjusted HR and 95% CI evaluating the relationship between statin use at baseline, as well as in a time‐dependent manner and risk of NHL, were computed from Cox proportional hazards analyses. A separate analysis was performed for individual NHL subtypes: diffuse large B‐Cell lymphoma (DLBCL) (n = 228), follicular lymphoma (n = 169), and small lymphocytic lymphoma (n = 74). All statistical tests were two‐sided. There was no significant association between use of statins at baseline and risk of NHL (HR 0.85, 95% C.I. 0.67–1.08). However, in the multivariable‐adjusted time‐dependent models, statin use was associated with a borderline lower risk of NHL (HR 0.81, 95% C.I. 0.66–1.00). Considering subtypes of NHL, statin use was associated with a lower risk of DLBCL (HR 0.62, 95% C.I. 0.42–0.91). This effect was driven by lipophilic statins (HR 0.62, 95% C.I. 0.40–0.96). In the WHI, statins were associated with a lower overall risk of DLBCL, particularly attributable to lipophilic statins. These results may have impact on primary or secondary prevention of NHL, particularly DLBCL.

Neuroprotective effects of statins against amyloid β-induced neurotoxicity

A growing body of evidence suggests that disruption of the homeostasis of lipid metabolism affects the pathogenesis of Alzheimer's disease (AD). In particular, dysregulation of cholesterol homeostasis in the brain has been reported to considerably increase the risk of developing AD. Thus, dysregulation of lipid homeostasis may increase the amyloid β (Aβ) levels by affecting amyloid precursor protein (APP) cleavage, which is the most important risk factor involved in the pathogenesis of AD. Previous research demonstrated that Aβ can trigger neuronal insulin resistance, which plays an important role in response to Aβ-induced neurotoxicity in AD. Epidemiological studies also suggested that statin use is associated with a decreased incidence of AD. Therefore, statins are believed to be a good candidate for conferring neuroprotective effects against AD. Statins may play a beneficial role in reducing Aβ-induced neurotoxicity. Their effect involves a putative mechanism beyond its cholesterol-lowering effects in preventing Aβ-induced neurotoxicity. However, the underlying molecular mechanisms of the protective effect of statins have not been clearly determined in Aβ-induced neurotoxicity. Given that statins may provide benefits beyond the inhibition of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, these drugs may also improve the brain. Thus, statins may have beneficial effects on impaired insulin signaling by activating AMP-activated protein kinase (AMPK) in neuronal cells. They play a potential therapeutic role in targeting Aβ-mediated neurotoxicity.

Therapy with atorvastatin versus rosuvastatin reduces urinary podocytes, podocyte-associated molecules, and proximal tubule dysfunction biomarkers in patients with type 2 diabetes mellitus: a pilot study

BACKGROUND

Diabetic nephropathy is a severe complication of Type 2 diabetes. Tubular lesions may play an important role in its early stages. The aim of our study was to determine if atorvastatin protects the podocytes and the proximal tubule in patients with Type 2 diabetes.

METHODS

A total of 63 patients with Type 2 diabetes completed this 6-months prospective pilot study. They were randomized to continue rosuvastatin therapy (control group) or to be administered an equipotent dose of atorvastatin (intervention group), and were assessed regarding urinary podocytes, podocyte-associated molecules, and biomarkers of proximal tubule dysfunction.

RESULTS

The patients from the intervention group presented a significant reduction in podocyturia (from 7.0 to 4.0 cells/ml, p < .05), urinary nephrin (from 1.7 to 1.3 mg/g, p < .001), urinary vascular endothelial growth factor (from 262.8 to 256.9, p < .01), urinary alpha1-microglobulin (from 10.0 to 8.3 mg/g, p < .01), urinary kidney injury molecule-1 (from 139.5 to 136.3 ng/g, p < .001), and urinary advanced glycation end-products (from 112.6 to 101.3 pg/ml, p < .001). Podocyturia correlated directly with the podocyte damage biomarkers, proximal tubule dysfunction biomarkers, albumin to creatinine ratio, and advanced glycation end-products, and inversely with the glomerular filtration rate.

CONCLUSIONS

In patients with Type 2 diabetes, atorvastatin exerts favorable effects on the kidney. There is a correlation between the evolution of the podocytes and of the proximal tubule biomarkers, supporting the hypothesis that the glomerular changes parallel proximal tubule dysfunction in the early stages of diabetic nephropathy.

Atorvastatin Promotes Phagocytosis and Attenuates Pro-Inflammatory Response in Human Retinal Pigment Epithelial Cells

Phagocytosis of daily shed photoreceptor outer segments is an important function of the retinal pigment epithelium (RPE) and it is essential for retinal homeostasis. RPE dysfunction, especially impairment of its phagocytic ability, plays an essential role in the pathogenesis of age-related macular degeneration (AMD). Statins, or HMG CoA (3-hydroxy-3-methylglutaryl-coenzyme A) reductase inhibitors, are drugs with multiple properties that have been extensively used to treat hyperlipidemia. However, their effect on RPE cells has not been fully elucidated. Here we report that high dose atorvastatin increased the phagocytic function of ARPE-19 cells, as well as rescue the cells from the phagocytic dysfunction induced by cholesterol crystals and oxidized low-density lipoproteins (ox-LDL), potentially by increasing the cellular membrane fluidity. Similar effects were observed when evaluating two other hydrophobic statins, lovastatin and simvastatin. Furthermore, atorvastatin was able to block the induction of interleukins IL-6 and IL-8 triggered by pathologic stimuli relevant to AMD, such as cholesterol crystals and ox-LDL. Our study shows that statins, a well-tolerated class of drugs with rare serious adverse effects, help preserve the phagocytic function of the RPE while also exhibiting anti-inflammatory properties. Both characteristics make statins a potential effective medication for the prevention and treatment of AMD.

Regression of Some High-risk Features of Age-related Macular Degeneration (AMD) in Patients Receiving Intensive Statin Treatment

Importance

Age-related macular degeneration (AMD) remains the leading cause of blindness in developed countries, and affects more than 150 million worldwide. Despite effective anti-angiogenic therapies for the less prevalent neovascular form of AMD, treatments are lacking for the more prevalent dry form. Similarities in risk factors and pathogenesis between AMD and atherosclerosis have led investigators to study the effects of statins on AMD incidence and progression with mixed results. A limitation of these studies has been the heterogeneity of AMD disease and the lack of standardization in statin dosage.

Objective

We were interested in studying the effects of high-dose statins, similar to those showing regression of atherosclerotic plaques, in AMD.

Design

Pilot multicenter open-label prospective clinical study of 26 patients with diagnosis of AMD and the presence of many large, soft drusenoid deposits. Patients received 80 mg of atorvastatin daily and were monitored at baseline and every 3 months with complete ophthalmologic exam, best corrected visual acuity (VA), fundus photographs, optical coherence tomography (OCT), and blood work (AST, ALT, CPK, total cholesterol, TSH, creatinine, as well as a pregnancy test for premenopausal women).

Results

Twenty-three subjects completed a minimum follow-up of 12 months. High-dose atorvastatin resulted in regression of drusen deposits associated with vision gain (+ 3.3 letters, p = 0.06) in 10 patients. No subjects progressed to advanced neovascular AMD.

Conclusions

High-dose statins may result in resolution of drusenoid pigment epithelial detachments (PEDs) and improvement in VA, without atrophy or neovascularization in a high-risk subgroup of AMD patients. Confirmation from larger studies is warranted.

•

High dose lipophilic statin administration was associated with regression of large soft drusen and vision gain in 10/23 AMD patients.

•

Duration of treatment before a positive response was observed was usually 1–1.5 years.

•

Patients on high-dose statin appeared to be protected from progression to “wet” neovascular-AMD.

There is a lack of effective therapies for dry age-related macular degeneration (AMD), one of the leading causes of blindness affecting millions. Although AMD shares similarities with atherosclerosis, prior studies on statins and AMD have failed to show improvement. A limitation of these studies has been the heterogeneity of AMD disease and the lack of standardization in statin dosage. Here, we present for the first time evidence that treatment with high-dose atorvastatin (80 mg) is associated with regression of lipid deposits and improvement in visual acuity, without atrophy or neovascularization, in high-risk AMD patients.

Review article: inhibition of methanogenic archaea by statins as a targeted management strategy for constipation and related disorders

BACKGROUND

Observational studies show a strong association between delayed intestinal transit and the production of methane. Experimental data suggest a direct inhibitory activity of methane on the colonic and ileal smooth muscle and a possible role for methane as a gasotransmitter. Archaea are the only confirmed biological sources of methane in nature and Methanobrevibacter smithii is the predominant methanogen in the human intestine.

AIM

To review the biosynthesis and composition of archaeal cell membranes, archaeal methanogenesis and the mechanism of action of statins in this context.

METHODS

Narrative review of the literature.

RESULTS

Statins can inhibit archaeal cell membrane biosynthesis without affecting bacterial numbers as demonstrated in livestock and humans. This opens the possibility of a therapeutic intervention that targets a specific aetiological factor of constipation while protecting the intestinal microbiome. While it is generally believed that statins inhibit methane production via their effect on cell membrane biosynthesis, mediated by inhibition of the HMG-CoA reductase, there is accumulating evidence for an alternative or additional mechanism of action where statins inhibit methanogenesis directly. It appears that this other mechanism may predominate when the lactone form of statins, particularly lovastatin lactone, is administered.

CONCLUSIONS

Clinical development appears promising. A phase 2 clinical trial is currently in progress that evaluates the effect of lovastatin lactone on methanogenesis and symptoms in patients with irritable bowel syndrome with constipation. The review concludes with an outlook for the future and subsequent work that needs to be done.

Binding energies of tyrosine kinase inhibitors: Error assessment of computational methods for imatinib and nilotinib binding

The binding energies of imatinib and nilotinib to tyrosine kinase have been determined by quantum mechanical (QM) computations, and compared with literature binding energy studies using molecular mechanics (MM). The potential errors in the computational methods include these critical factors. Errors in X-ray structures such as structural distortions and steric clashes give unrealistically high van der Waals energies, and erroneous binding energies.MM optimization gives a very different configuration to the QM optimization for nilotinib, whereas the imatinib ion gives similar configurations. Solvation energies are a major component of the overall binding energy. The QM based solvent model (PCM/SMD) gives different values from those used in the implicit PBSA solvent MM models. A major error in inhibitor—kinase binding lies in the non-polar solvation terms. Solvent transfer free energies and the required empirical solvent accessible surface area factors for nilotinib and imatinib ion to give the transfer free energies have been reverse calculated. These values differ from those used in the MM PBSA studies.An intertwined desolvation—conformational binding selectivity process is a balance of thermodynamic desolvation and intramolecular conformational kinetic control.The configurational entropies (TΔS) are minor error sources.

Statins and breast cancer stage and mortality in the Women's Health Initiative

PURPOSE

To evaluate the association between statins and breast cancer stage and mortality in the Women's Health Initiative.

METHODS

The study population included 128,675 postmenopausal women aged 50-79 years, out of which there were 7,883 newly diagnosed cases of in situ (19%), local (61%)-, regional (19%)- and distant (1%)-stage breast cancer and 401 deaths due to breast cancer after an average of 11.5 (SD = 3.7) years of follow-up. Stage was coded using SEER criteria and was stratified into early (in situ and local)- versus late (regional and distant)-stage disease. Information on statins and other risk factors were collected by self- and interviewer-administered questionnaires. Cause of death was based on medical record review. Multivariable-adjusted hazards ratios (HR) and 95% confidence intervals (CIs) evaluating the relationship between statin use (at baseline only and in a time-dependent manner) and diagnosis of late-stage breast cancer and breast cancer-specific mortality were computed from Cox proportional hazards analyses after adjusting for appropriate confounders.

RESULTS

Statins were used by 10,474 women (8%) at baseline. In the multivariable-adjusted time-dependent model, use of lipophilic statins was associated with a reduction in diagnosis of late-stage breast cancer (HR 0.80, 95% CI 0.64-0.98, p = 0.035) which was also significant among women with estrogen receptor-positive disease (HR 0.72, 95% CI 0.56-0.93, p = 0.012). Breast cancer mortality was marginally lower in statin users compared with nonusers (HR 0.59, 95 % CI 0.32-1.06, p = 0.075).

CONCLUSIONS

Prior statin use is associated with lower breast cancer stage at diagnosis.