Role of Rho-Associated Kinase in the Pathophysiology of Cerebral Cavernous Malformations.

Cerebral cavernous malformations (CCMs) are vascular lesions characterized by a porous endothelium. The lack of a sufficient endothelial barrier can result in microbleeds and frank intracerebral hemorrhage. A primary mechanism for lesion development is a sequence variant in at least 1 of the 3 CCM genes (CCM1, CCM2, and CCM3), which influence various signaling pathways that lead to the CCM phenotype. A common downstream process associated with CCM gene loss of function involves overactivation of RhoA and its effector Rho-associated kinase (ROCK). In this study, we review RhoA/ROCK-related mechanisms involved in CCM pathophysiology as potential therapeutic targets. Literature searches were conducted in PubMed using combinations of search terms related to RhoA/ROCK and CCMs. In endothelial cells, CCM1, CCM2, and CCM3 proteins normally associate to form the CCM protein complex, which regulates the functions of a wide variety of protein targets (e.g., MAP3K3, SMURF1, SOK-1, and ICAP-1) that directly or indirectly increase RhoA/ROCK activity. Loss of CCM complex function and increased RhoA/ROCK activity can lead to the formation of stress fibers that contribute to endothelial junction instability. Other RhoA/ROCK-mediated pathophysiologic outcomes include a shift to a senescence-associated secretory phenotype (primarily mediated by ROCK2), which is characterized by endothelial cell migration, cell cycle arrest, extracellular matrix degradation, leukocyte chemotaxis, and inflammation. ROCK represents a potential therapeutic target, and direct (fasudil, NRL-1049) and indirect (statins) ROCK inhibitors have demonstrated various levels of efficacy in reducing lesion burden in preclinical models of CCM. Current (atorvastatin) and planned (NRL-1049) clinical studies will determine the efficacy of ROCK inhibitors for CCM in humans, for which no US Food and Drug Administration-approved or EU-approved pharmacologic treatment exists.

Understanding the molecular mechanisms of statin pleiotropic effects.

Statins represent the cornerstone of pharmacotherapy for the prevention of atherosclerotic cardiovascular disease. These medications not only reduce low-density lipoprotein cholesterol (LDL-C) via inhibition of 3-hydroxy-3-methylglutarate attached to CoA reductase, the key rate-limiting step in the cholesterol biosynthetic pathway, but also upregulate expression of the low-density lipoprotein receptor, improving serum clearance. Given LDL-C is a causal risk factor for the development of atherosclerosis, these complementary mechanisms largely explain why statin therapy leads to reductions in major adverse cardiovascular events. However, decades of basic and clinical research have suggested that statins may exert other effects independent of LDL-C lowering, termed pleiotropic effects, which have become a topic of debate among the scientific community. While some literature suggests statins may improve plaque stability, reduce inflammation and thrombosis, decrease oxidative stress, and improve endothelial function and vascular tone, other studies have suggested potential harmful pleiotropic effects related to increased risk of muscle-related side effects, diabetes, hemorrhagic stroke, and cognitive decline. Furthermore, the introduction of newer, non-statin LDL-C lowering therapies, including ezetimibe, proprotein convertase subtilisin/Kexin Type 9, and bempedoic acid, have challenged the statin pleiotropy theory. This review aims to provide a historical background on the development of statins, explore the mechanistic underpinnings of statin pleiotropy, review the available literature, and provide up to date examples that suggest statins may exert effects outside of LDL-C lowering and the cardiovascular system.

A Novel HIF-2α/ARNT Signaling Pathway Protects Against Microvascular Dysfunction and heart failure After Myocardial Infarction.

RATIONALE: Cardiac microvascular leakage and inflammation are triggered during myocardial infarction (MI) and contribute to heart failure. Hypoxia-inducible factor 2α (Hif2α) is highly expressed in endothelial cells (ECs) and rapidly activated by myocardial ischemia, but whether it has a role in endothelial barrier function during MI is unclear. OBJECTIVE: To test our hypothesis that the expression of Hif2α and its binding partner aryl hydrocarbon nuclear translocator (ARNT) in ECs regulate cardiac microvascular permeability in infarcted hearts. METHODS AND RESULTS: Experiments were conducted with mice carrying an inducible EC-specific Hif2α-knockout (ecHif2α-/-) mutation, with mouse cardiac microvascular endothelial cells (CMVECs) isolated from the hearts of ecHif2α-/- mice after the mutation was induced, and with human CMVECs and umbilical-vein endothelial cells transfected with ecHif2α siRNA. After MI induction, echocardiographic assessments of cardiac function were significantly lower, while measures of cardiac microvascular leakage (Evans blue assay), plasma IL6 levels, and cardiac neutrophil accumulation and fibrosis (histology) were significantly greater, in ecHif2α-/- mice than in control mice, and RNA-sequencing analysis of heart tissues from both groups indicated that the expression of genes involved in vascular permeability and collagen synthesis was enriched in ecHif2α-/- hearts. In cultured ECs, ecHif2α deficiency was associated with declines in endothelial barrier function (electrical cell impedance assay) and the reduced abundance of tight-junction proteins, as well as an increase in the expression of inflammatory markers, all of which were largely reversed by the overexpression of ARNT. We also found that ARNT, but not Hif2α, binds directly to the IL6 promoter and suppresses IL6 expression. CONCLUSIONS: EC-specific deficiencies in Hif2α expression significantly increase cardiac microvascular permeability, promote inflammation, and reduce cardiac function in infarcted mouse hearts, and ARNT overexpression can reverse the upregulation of inflammatory genes and restore endothelial-barrier function in Hif2α-deficient ECs.

Tie2-Cre-Induced Inactivation of Non-Nuclear Estrogen Receptor-α Signaling Abrogates Estrogen Protection Against Vascular Injury.

Using the Cre-loxP system, we generated the first mouse model in which estrogen receptor-α non-nuclear signaling was inactivated in endothelial cells. Estrogen protection against mechanical vascular injury was impaired in this model. This result indicates the pivotal role of endothelial estrogen receptor-α non-nuclear signaling in the vasculoprotective effects of estrogen.

Involvement of Rho-Associated Coiled-Coil Containing Kinase (ROCK) in BCR-ABL1 Tyrosine Kinase Inhibitor Cardiovascular Toxicity.

Background: Second- and third-generation BCR-ABL1 tyrosine kinase inhibitors (TKIs) are associated with cardiovascular adverse events (CVAEs) in patients with Philadelphia chromosome-positive (Ph+) leukemia. Objectives: We hypothesized that second- and third-generation BCR-ABL1 TKIs may cause CVAEs through the activation of Rho-associated coiled-coil containing kinase (ROCK). Methods: Peripheral blood mononuclear cells from 53 Ph+ patients on TKIs and 15 control patients without Ph+ leukemia were assessed for ROCK activity through capillary electrophoresis (median follow-up = 26 months [Q1-Q3: 5-37 months]). We also investigated the effects of TKIs and ROCK on endothelial dysfunction in vitro, which could contribute to CVAEs. Results: Patients receiving second- and third-generation TKIs had 1.6-fold greater ROCK activity compared with patients receiving imatinib and control patients. Elevated ROCK activity was associated with an increased incidence of CVAEs in Ph+ leukemia patients. In endothelial cells in vitro, we found that dasatinib and ponatinib treatment led to changes in actin intensity and endothelial permeability, which can be reversed by pharmacologic inhibition of ROCK. Ponatinib led to decreased cell proliferation, but this was not accompanied by senescence. Dasatinib and ponatinib treatment led to phosphor-inhibition of endothelial nitric oxide synthase and decreased nitric oxide production. ROCK inhibition reversed endothelial permeability and endothelial nitric oxide synthase-related endothelial dysfunction. Imatinib and nilotinib induce phosphorylation of p190RhoGAP. Conclusions: Our findings suggest ROCK activity may be a prognostic indicator of CVAEs in patients receiving BCR-ABL1 TKIs. With further study, ROCK inhibition may be a promising approach to reduce the incidence of CVAEs associated with second- and third-generation BCR-ABL1 TKIs.

Emerging views of statin pleiotropy and cholesterol lowering.

Over the past four decades, no class of drugs has had more impact on cardiovascular health than the 3-hydroxy-methylglutaryl coenzyme A reductase inhibitors or statins. Developed as potent lipid-lowering agents, statins were later shown to reduce morbidity and mortality of patients who are at risk for cardiovascular disease. However, retrospective analyses of some of these clinical trials have uncovered some aspects of their clinical benefits that may be additional to their lipid-lowering effects. Such 'pleiotropic' effects of statins garnered intense interest and debate over its contribution to cardiovascular risk reduction. This review will provide a brief background of statin pleiotropy, assess the available clinical evidence for and against their non-lipid-lowering benefits, and propose future research directions in this field.

Vascular Stiffening Mediated by Rho-Associated Coiled-Coil Containing Kinase Isoforms.

Background The pathogenesis of vascular stiffening and hypertension is marked by non-compliance of vessel wall because of deposition of collagen fibers, loss of elastin fibers, and increased vascular thickening. Rho/Rho-associated coiled-coil containing kinases 1 and 2 (ROCK1 and ROCK2) have been shown to regulate cellular contraction and vascular remodeling. However, the role of ROCK isoforms in mediating pathogenesis of vascular stiffening and hypertension is not known. Methods and Results Hemizygous Rock mice (Rock1+/- and Rock2+/-) were used to determine the role of ROCK1 and ROCK2 in age-related vascular dysfunction. Both ROCK activity and aortic stiffness increased to a greater extent with age in wild-type mice compared with that of Rock1+/- and Rock2+/- mice. As a model for age-related vascular stiffening, we administered angiotensin II (500 ng/kg per minute) combined with nitric oxide synthase inhibitor, L-Nω-nitroarginine methyl ester (0.5 g/L) for 4 weeks to 12-week-old male Rock1+/- and Rock2+/- mice. Similar to advancing age, angiotensin II/L-Nω-nitroarginine methyl ester caused increased blood pressure, aortic stiffening, and vascular remodeling, which were attenuated in Rock2+/-, and to a lesser extent, Rock1+/- mice. The reduction of aortic stiffening in Rock2+/- mice was accompanied by decreased collagen deposition, relatively preserved elastin content, and less aortic wall hypertrophy. Indeed, the upregulation of collagen I by transforming growth factor-ß1 or angiotensin II was greatly attenuated in Rock2-/- mouse embryonic fibroblasts. Conclusions These findings indicate that ROCK1 and ROCK2 mediate both age-related and pharmacologically induced aortic stiffening, and suggest that inhibition of ROCK2, and to a lesser extent ROCK1, may have therapeutic benefits in preventing age-related vascular stiffening.

Increase in Blood-Brain Barrier (BBB) Permeability Is Regulated by MMP3 via the ERK Signaling Pathway.

BACKGROUND: The blood-brain barrier (BBB) regulates the exchange of molecules between the brain and peripheral blood and is composed primarily of microvascular endothelial cells (BMVECs), which form the lining of cerebral blood vessels and are linked via tight junctions (TJs). The BBB is regulated by components of the extracellular matrix (ECM), and matrix metalloproteinase 3 (MMP3) remodels the ECM's basal lamina, which forms part of the BBB. Oxidative stress is implicated in activation of MMPs and impaired BBB. Thus, we investigated whether MMP3 modulates BBB permeability. METHODS: Experiments included in vivo assessments of isoflurane anesthesia and dye extravasation from brain in wild-type (WT) and MMP3-deficient (MMP3-KO) mice, as well as in vitro assessments of the integrity of monolayers of WT and MMP3-KO BMVECs and the expression of junction proteins. RESULTS: Compared to WT mice, measurements of isoflurane usage and anesthesia induction time were higher in MMP3-KO mice and lower in WT that had been treated with MMP3 (WT+MMP3), while anesthesia emergence times were shorter in MMP3-KO mice and longer in WT+MMP3 mice than in WT. Extravasation of systemically administered dyes was also lower in MMP3-KO mouse brains and higher in WT+MMP3 mouse brains, than in the brains of WT mice. The results from both TEER and Transwell assays indicated that MMP3 deficiency (or inhibition) increased, while MMP3 upregulation reduced barrier integrity in either BMVEC or the coculture. MMP3 deficiency also increased the abundance of TJs and VE-cadherin proteins in BMVECs, and the protein abundance declined when MMP3 activity was upregulated in BMVECs, but not when the cells were treated with an inhibitor of extracellular signal related-kinase (ERK). CONCLUSION: MMP3 increases BBB permeability following the administration of isoflurane by upregulating the ERK signaling pathway, which subsequently reduces TJ and VE-cadherin proteins in BMVECs.

SALAD-BAAR: A numerical risk score for hospital admission or emergency department presentation in ambulatory patients with cardiovascular disease.

BACKGROUND: While many interventions to reduce hospital admissions and emergency department (ED) visits for patients with cardiovascular disease have been developed, identifying ambulatory cardiac patients at high risk for admission can be challenging. HYPOTHESIS: A computational model based on readily accessible clinical data can identify patients at risk for admission. METHODS: Electronic health record (EHR) data from a tertiary referral center were used to generate decision tree and logistic regression models. International Classification of Disease (ICD) codes, labs, admissions, medications, vital signs, and socioenvironmental variables were used to model risk for ED presentation or hospital admission within 90 days following a cardiology clinic visit. Model training and testing were performed with a 70:30 data split. The final model was then prospectively validated. RESULTS: A total of 9326 patients and 46 465 clinic visits were analyzed. A decision tree model using 75 patient characteristics achieved an area under the curve (AUC) of 0.75 and a logistic regression model achieved an AUC of 0.73. A simplified 9-feature model based on logistic regression odds ratios achieved an AUC of 0.72. A further simplified numerical score assigning 1 or 2 points to each variable achieved an AUC of 0.66, specificity of 0.75, and sensitivity of 0.58. Prospectively, this final model maintained its predictive performance (AUC 0.63-0.60). CONCLUSION: Nine patient characteristics from routine EHR data can be used to inform a highly specific model for hospital admission or ED presentation in cardiac patients. This model can be simplified to a risk score that is easily calculated and retains predictive performance.

Regulator of G-Protein Signaling 5 Maintains Brain Endothelial Cell Function in Focal Cerebral Ischemia.

Background Regulator of G-protein signaling 5 (RGS5) is a negative modulator of G-protein-coupled receptors. The role of RGS5 in brain endothelial cells is not known. We hypothesized that RGS5 in brain microvascular endothelial cells may be an important mediator of blood-brain barrier function and stroke severity after focal cerebral ischemia. Methods and Results Using a transient middle cerebral artery occlusion model, we found that mice with global and endothelial-specific deletion of Rgs5 exhibited larger cerebral infarct size, greater neurological motor deficits, and increased brain edema. In our in vitro models, we observed increased Gq activity and elevated intracellular Ca2+ levels in brain endothelial cells. Furthermore, the loss of endothelial RGS5 leads to decreased endothelial NO synthase expression and phosphorylation, relocalization of endothelial tight junction proteins, and increased cell permeability. Indeed, RGS5 deficiency leads to increased Rho-associated kinase and myosin light chain kinase activity, which were partially reversed in our in vitro model by pharmacological inhibition of Gq, metabotropic glutamate receptor 1, and ligand-gated ionotropic glutamate receptor. Conclusions Our findings indicate that endothelial RGS5 plays a novel neuroprotective role in focal cerebral ischemia. Loss of endothelial RGS5 leads to hyperresponsiveness to glutamate signaling pathways, enhanced Rho-associated kinase- and myosin light chain kinase-mediated actin-cytoskeleton reorganization, endothelial dysfunction, tight junction protein relocalization, increased blood-brain barrier permeability, and greater stroke severity. These findings suggest that preservation of endothelial RGS5 may be an important therapeutic strategy for maintaining blood-brain barrier integrity and limiting the severity of ischemic stroke.

Serine-threonine kinase ROCK2 regulates germinal center B cell positioning and cholesterol biosynthesis.

Germinal center (GC) responses require B cells to respond to a dynamic set of intercellular and microenvironmental signals that instruct B cell positioning, differentiation, and metabolic reprogramming. RHO-associated coiled-coil-containing protein kinase 2 (ROCK2), a serine-threonine kinase that can be therapeutically targeted by ROCK inhibitors or statins, is a key downstream effector of RHOA GTPases. Although RHOA-mediated pathways are emerging as critical regulators of GC responses, the role of ROCK2 in B cells is unknown. Here, we found that ROCK2 was activated in response to key T cell signals like CD40 and IL-21 and that it regulated GC formation and maintenance. RNA-Seq analyses revealed that ROCK2 controlled a unique transcriptional program in GC B cells that promoted optimal GC polarization and cholesterol biosynthesis. ROCK2 regulated this program by restraining AKT activation and subsequently enhancing FOXO1 activity. ATAC-Seq (assay for transposase-accessible chromatin with high-throughput sequencing) and biochemical analyses revealed that the effects of ROCK2 on cholesterol biosynthesis were instead mediated via a novel mechanism. ROCK2 directly phosphorylated interferon regulatory factor 8 (IRF8), a crucial mediator of GC responses, and promoted its interaction with sterol regulatory element-binding transcription factor 2 (SREBP2) at key regulatory regions controlling the expression of cholesterol biosynthetic enzymes, resulting in optimal recruitment of SREBP2 at these sites. These findings thus uncover ROCK2 as a multifaceted and therapeutically targetable regulator of GC responses.

Community Health Workers Reduce Rehospitalizations and Emergency Department Visits for Low-Socioeconomic Urban Patients With Heart Failure.

BACKGROUND: Low-socioeconomic, urban, minority patients with heart failure (HF) often have unique barriers to care. Community health workers (CHWs) are specially trained laypeople who serve as liaisons between underserved communities and the health system. It is not known whether CHWs improve outcomes in low-socioeconomic, urban, minority patients with HF. HYPOTHESIS: CHWs reduce rehospitalizations, emergency department (ED) visits, and healthcare costs for low-socioeconomic urban patients with HF. METHODS: Patients admitted with acute decompensated HF were assigned to receive weekly visits by CHW after discharge. Patients were propensity score matched with controls who received usual care. HF-related rehospitalizations, ED visits, and inpatient costs were compared for 12 months following index admission versus the same period before. RESULTS: Twenty-eight patients who received weekly visits from a CHW for 12 months after discharge were matched with 28 control patients who did not receive CHWs. Patients who received a CHW had a 75% decrease in HF-related ED visits (0.71 vs. 0.18 visits per patient, P < 0.001), an 89% decrease in HF-related readmissions (0.64 vs. 0.07 admissions per patient, P < 0.005), and a significant decrease in inpatient cost for HF-related visits. In controls receiving usual care, there was no significant change in hospitalizations, ED visits, or costs. CONCLUSIONS: In conclusion, CHWs are associated with reduced rehospitalizations, ED visits, and inpatient costs in low-socioeconomic, urban, minority patients with HF. CHWs may be a cost-effective method to reduce health care utilization and improve outcomes for this population.

Targeting Rho-associated coiled-coil forming protein kinase (ROCK) in cardiovascular fibrosis and stiffening.

Introduction: Pathological cardiac fibrosis, through excessive extracellular matrix protein deposition from fibroblasts and pro-fibrotic immune responses and vascular stiffening is associated with most forms of cardiovascular disease. Pathological cardiac fibrosis and stiffening can lead to heart failure and arrythmias and vascular stiffening may lead to hypertension. ROCK, a serine/threonine kinase downstream of the Rho-family of GTPases, may regulate many pro-fibrotic and pro-stiffening signaling pathways in numerous cell types.Areas covered: This article outlines the molecular mechanisms by which ROCK in fibroblasts, T helper cells, endothelial cells, vascular smooth muscle cells, and macrophages mediate fibrosis and stiffening. We speculate on how ROCK could be targeted to inhibit cardiovascular fibrosis and stiffening.Expert opinion: Critical gaps in knowledge must be addressed if ROCK inhibitors are to be used in the clinic. Numerous studies indicate that each ROCK isoform may play differential roles in regulating fibrosis and may have opposing roles in specific tissues. Future work needs to highlight the isoform- and tissue-specific contributions of ROCK in fibrosis, and how isoform-specific ROCK inhibitors in murine models and in clinical trials affect the pathophysiology of cardiac fibrosis and stiffening. This could progress knowledge regarding new treatments for heart failure, arrythmias and hypertension and the repair processes after myocardial infarction.

A Brain-Targeted Orally Available ROCK2 Inhibitor Benefits Mild and Aggressive Cavernous Angioma Disease.

Cavernous angioma (CA) is a vascular pathology caused by loss of function in one of the 3 CA genes (CCM1, CCM2, and CCM3) that result in rho kinase (ROCK) activation. We investigated a novel ROCK2 selective inhibitor for the ability to reduce brain lesion formation, growth, and maturation. We used genetic methods to explore the use of a ROCK2-selective kinase inhibitor to reduce growth and hemorrhage of CAs. The role of ROCK2 in CA was investigated by crossing Rock1 or Rock2 hemizygous mice with Ccm1 or Ccm3 hemizygous mice, and we found reduced lesions in the Rock2 hemizygous mice. A ROCK2-selective inhibitor, BA-1049 was used to investigate efficacy in reducing CA lesions after oral administration to Ccm1+/- and Ccm3+/- mice that were bred into a mutator background. After assessing the dose range effective to target brain endothelial cells in an ischemic brain model, Ccm1+/- and Ccm3+/- transgenic mice were treated for 3 (Ccm3+/-) or 4 months (Ccm1+/-), concurrently, randomized to receive one of three doses of BA-1049 in drinking water, or placebo. Lesion volumes were assessed by micro-computed tomography. BA-1049 reduced activation of ROCK2 in Ccm3+/-Trp53-/- lesions. Ccm1+/-Msh2-/- (n=68) and Ccm3+/-Trp53-/- (n=71) mice treated with BA-1049 or placebo showed a significant dose-dependent reduction in lesion volume after treatment with BA-1049, and a reduction in hemorrhage (iron deposition) near lesions at all doses. These translational studies show that BA-1049 is a promising therapeutic agent for the treatment of CA, a disease with no current treatment except surgical removal of the brain lesions.

Association of Rising Violent Crime With Blood Pressure and Cardiovascular Risk: Longitudinal Evidence From Chicago, 2014-2016.

BACKGROUND: The purpose of this study was to examine the longitudinal association between rising violent crime and elevated blood pressure (BP). METHODS: We analyzed 217,816 BP measurements from 17,783 adults during a temporal surge in violent crime in Chicago (2014-2016). Serial observations were abstracted from the electronic health record at an academic medical center and paired to the City of Chicago Police Data Portal. The violent crime rate (VCR) was calculated as the number of violent crimes per 1,000 population per year for each census tract. Longitudinal multilevel regression models were implemented to assess elevated BP (systolic BP ≥ 140 mm Hg or diastolic BP ≥ 90 mm Hg) as a function of the VCR, adjusting for patient characteristics, neighborhood characteristics, and time effects. Secondary dependent measures included elevated heart rate, obesity, missed outpatient appointments, all-cause hospital admissions, and cardiovascular hospital admissions. RESULTS: At baseline, the median VCR was 41.3 (interquartile range: 15.2-66.8), with a maximum rise in VCR of 59.1 over the 3-year surge period. A 20-unit rise in the VCR was associated with 3% higher adjusted odds of having elevated BP (95% confidence interval [CI]: 1.01-1.06), 8% higher adjusted odds of missing an outpatient appointment (95% CI: 1.03-1.13), and 6% higher adjusted odds of having a cardiovascular-related hospital admission (95% CI: 1.01-1.12); associations were not significant for elevated heart rate and obesity. CONCLUSION: Rising violent crime was associated with increased BP during a temporal crime surge.

Rho Kinase Inhibition Blunts Lesion Development and Hemorrhage in Murine Models of Aggressive Pdcd10/Ccm3 Disease.

Background and Purpose- Previously, murine models Krit1 +/- Msh2 -/- and Ccm2 +/- Trp53 -/- showed a reduction or no effect on cerebral cavernous malformation (CCM) burden and favorable effects on lesional hemorrhage by the robust Rock (Rho-associated protein kinase) inhibitor fasudil and by simvastatin (a weak pleiotropic inhibitor of Rock). Herein, we concurrently investigated treatment of the more aggressive Pdcd10/Ccm3 model with fasudil, simvastatin, and higher dose atorvastatin to determined effectiveness of Rock inhibition. Methods- The murine models, Pdcd10 +/- Trp53 -/- and Pdcd10 +/- Msh2 -/-, were contemporaneously treated from weaning to 5 months of age with fasudil (100 mg/kg per day in drinking water, n=9), simvastatin (40 mg/kg per day in chow, n=11), atorvastatin (80 mg/kg per day in chow, n=10), or with placebo (n=16). We assessed CCM volume in mouse brains by microcomputed tomography. Lesion burden was calculated as lesion volume normalized to total brain volume. We analyzed chronic hemorrhage in CCM lesions by quantitative intensity of Perls staining in brain sections. Results- The Pdcd10 +/- Trp53 -/- /Msh2 -/- models showed a mean CCM lesion burden per mouse reduction from 0.0091 in placebos to 0.0042 ( P=0.027) by fasudil, and to 0.0047 ( P=0.025) by atorvastatin treatment, but was not changed significantly by simvastatin. Hemorrhage intensity per brain was commensurately decreased by Rock inhibition. Conclusions- These results support the exploration of proof of concept effect of high-dose atorvastatin on human CCM disease for potential therapeutic testing.

The Pleiotropic Effects of Statins - From Coronary Artery Disease and Stroke to Atrial Fibrillation and Ventricular Tachyarrhythmia.

Statins, 3-hydroxy-methylglutaryl coenzyme A reductase inhibitors, have been used for decades for the prevention of coronary artery disease and stroke. They act primarily by lowering serum cholesterol through the inhibition of cholesterol synthesis in the liver, which results in the upregulation of low-density lipoprotein receptors in the liver. This results in the removal of low-density lipoproteincholesterol. Studies have suggested that statins may demonstrate additional effects that are independent of their effects on low-density lipoprotein-cholesterol. These have been termed "pleiotropic" effects. Pleiotropic effects may be due to the inhibition of isoprenoid intermediates by statins. Isoprenoid inhibition has effects on the small guanosine triphosphate binding proteins Rac and Rho which in turn effects nicotinamide adenine dinucleotide phosphate oxidases. Therefore, there are changes in endothelial nitric oxide synthase expression, atherosclerotic plaque stability, pro-inflammatory cytokines and reactive oxygen species production, platelet reactivity, and cardiac fibrosis and hypetrophy development. Recently, statins have been compared to the ezetimibe and the recently published outcomes data on the proprotein convertase subtilisin kexin type 9 inhibitors has allowed for a reexamination of statin pleiotropy. As a result of these diverse effects, it has been suggested that statins also have anti-arrhythmic effects. This review focuses on the mechanisms of statin pleiotropy and discusses evidence from the statin clinical trials as well as examining the possible anti-arrhythmic effects atrial fibrillation and ventricular tachyarrhythmias.

Atorvastatin Treatment of Cavernous Angiomas with Symptomatic Hemorrhage Exploratory Proof of Concept (AT CASH EPOC) Trial.

BACKGROUND: More than a million Americans harbor a cerebral cavernous angioma (CA), and those who suffer a prior symptomatic hemorrhage have an exceptionally high rebleeding risk. Preclinical studies show that atorvastatin blunts CA lesion development and hemorrhage through inhibiting RhoA kinase (ROCK), suggesting it may confer a therapeutic benefit. OBJECTIVE: To evaluate whether atorvastatin produces a difference compared to placebo in lesional iron deposition as assessed by quantitative susceptibility mapping (QSM) on magnetic resonance imaging in CAs that have demonstrated a symptomatic hemorrhage in the prior year. Secondary aims shall assess effects on vascular permeability, ROCK activity in peripheral leukocytes, signal effects on clinical outcomes, adverse events, and prespecified subgroups. METHODS: The phase I/IIa placebo-controlled, double-blinded, single-site clinical trial aims to enroll 80 subjects randomized 1-1 to atorvastatin (starting dose 80 mg PO daily) or placebo. Dosing shall continue for 24-mo or until reaching a safety endpoint. EXPECTED OUTCOMES: The trial is powered to detect an absolute difference of 20% in the mean percent change in lesional QSM per year (2-tailed, power 0.9, alpha 0.05). A decrease in QSM change would be a signal of potential benefit, and an increase would signal a safety concern with the drug. DISCUSSION: With firm mechanistic rationale, rigorous preclinical discoveries, and biomarker validations, the trial shall explore a proof of concept effect of a widely used repurposed drug in stabilizing CAs after a symptomatic hemorrhage. This will be the first clinical trial of a drug aimed at altering rebleeding in CA.