Joshua DeLeon

The gut microbiome and elevated cardiovascular risk in obesity and autoimmunity

Cardiovascular disease associated with obesity and autoimmunity is the leading cause of death in these populations and significant residual risk remains despite current treatment approaches. Obesity, type 1 diabetes mellitus (T1DM), rheumatoid arthritis (RA), and systemic lupus erythematosus (SLE) are linked to chronic inflammation, and subjects with these disorders have characteristic shifts in their gut microbiome composition. Recent data suggest that alterations in gut microbial and metabolic composition may be responsible, in part, for induction of chronic inflammation, thus promoting cardiovascular disease. Common microbiome changes observed in obesity, T1DM, RA, and SLE include a decrease in the ratio of bacteria, such as Gram-positive Firmicutes to Gram-negative Bacteroidetes, as well as an overabundance or depletion of certain species, including Prevotella copri. The consequent effects of these shifts include alterations in the metabolic composition of the gut, hyper-activation of toll-like receptor 4 (TLR-4), upregulation of inflammatory pathways, e.g. c-Jun N-terminal kinase and nuclear factor-kappa B (NFκB), increased intestinal permeability, increased C-reactive protein, and increased levels of trimethylamine N-oxide (TMAO). Differential microbiome compositions may also explain sex differences observed in autoimmunity, where a male gut microbiome promotes anti-inflammatory processes as compared to a female pro-inflammatory gut microbiome. Intervention at the level of the microbiota appears to attenuate symptoms in these inflammatory syndromes with probiotic treatment, such as Lactobacilli, playing a uniquely beneficial role in restoring intestinal health, decreasing inflammation, and reducing cardiovascular disease. This review will discuss obesity, T1DM, RA, and SLE in the context of how each unique microbiome profile contributes to elevated cardiovascular risk.

Resveratrol counters systemic lupus erythematosus-associated atherogenicity by normalizing cholesterol efflux.

Resveratrol is a bioactive molecule used in dietary supplements and herbal medicines and consumed worldwide. Numerous investigations by our group and others have indicated cardioprotective and anti-inflammatory properties of resveratrol. The present study explored potential atheroprotective actions of resveratrol on cholesterol efflux in cultured human macrophages exposed to plasma from systemic lupus erythematosus (SLE) patients. These results were confirmed in ApoE−/−Fas−/− double knockout mice, displaying a lupus profile with accelerated atherosclerosis. Resveratrol treatment attenuated atherosclerosis in these mice. THP-1 human macrophages were exposed to 10% pooled or individual plasma from patients who met diagnostic criteria for SLE. Expression of multiple proteins involved in reverse cholesterol transport (ABCA1, ABCG1, SR-B1, and cytochrome P450 27-hydroxylase) was assessed using QRT-PCR and Western blotting techniques. Ten-week-old ApoE−/−Fas−/− double knockout mice (n = 30) were randomly divided into two equal groups of 15, one of which received 0.01% resveratrol for 10 consecutive weeks. Atherosclerosis progression was evaluated in murine aortas. Bone marrow-derived macrophages (BMDM) were cultured and expression of cholesterol efflux proteins was analyzed in each group of mice. Our data indicate that inhibition of cholesterol efflux by lupus plasma in THP-1 human macrophages is rescued by resveratrol. Similarly, administration of resveratrol in a lupus-like murine model reduces plaque formation in vivo and augments cholesterol efflux in BMDM. This study presents evidence for a beneficial role of resveratrol in atherosclerosis in the specific setting of SLE. Therefore, resveratrol may merit investigation as an additional resource available to reduce lipid deposition and atherosclerosis in humans, especially in such vulnerable populations as lupus patients.

Is intra‐procedure three‐dimensional transesophageal echocardiogram an alternative to preprocedure multidetector computed tomography for the measurement of the aortic annulus in patients undergoing transcatheter aortic valve replacement?

The role of three‐dimensional transesophageal echocardiography (3DTEE) vs multidetector computed tomography (MDCT) in aortic annular sizing has been poorly defined in patients undergoing transcatheter aortic valve replacements (TAVR). We set to determine the correlation between 3DTEE and MDCT in measuring the aortic annulus prior to TAVR.

BMI-DEPENDENT EFFECTS OF ADIPOSE TISSUE EXOSOMES ON HUMAN MACROPHAGE CHOLESTEROL TRANSPORT GENE EXPRESSION

Obesity, a major risk for atherosclerotic cardiovascular disease, has quadrupled in adolescents in the last 30 years. How adipose tissue influences the pathological process of atherosclerosis is not well understood. This study compares cholesterol efflux gene expression in human macrophages exposed

MP1: CORRECTING ATHEROGENIC EFFECTS OF LUPUS PLASMA ON MACROPHAGES WITH RESVERATROL AND MYCOPHENOLATE

Purpose of Study Premature atherosclerosis with coronary artery disease is a major cause of morbidity in Systemic Lupus Erythematosus (SLE). SLE patient plasma induces a pro-atherogenic profile of cholesterol transport genes in macrophages. A common immunosuppressive treatment for SLE, mycophenolate (MMF) reduces scavenger receptors thus reducing lipid influx. We have demonstrated atheroprotective properties of the polyphenol resveratrol on cholesterol efflux. This study determines whether MMF and resveratrol work synergistically to regulate cholesterol transport in macrophages exposed to pro-atherogenic SLE plasma. Methods Used THP-1 human macrophages (106/ml) were incubated in 10% SLE plasma with: media (control); MMF (1 µg/ml); resveratrol (50 µM); and MMF+resveratrol. After 24 h incubation, total RNA and protein were isolated. Message level of scavenger receptors CD36, LOX1, and SRA1; and efflux proteins 27-hydroxylase, ATP binding cassette transporter (ABC)A1, and ABCG1 were evaluated by QRT-PCR and confirmed by immunoblot. Cholesterol efflux was measured by Amplex Red Cholesterol Assay kit run±cholesterol esterase. Summary of Results In 10% SLE plasma, MMF suppressed efflux genes ABCA1 and ABCG1 (58.38±3.5% and 72.98±3.3%) vs. SLE plasma alone (p<0.0001) while MMF+resveratrol corrected this suppression. In SLE plasma, MMF+resveratrol decreased ScrA1 and LOX-1 by 15±2.5% and 47±1.0%, respectively vs. resveratrol alone (p<0.0001). SLE plasma promoted cholesterol accumulation in THP-1 macrophages and prevented efflux into medium. It increased the ratio of cholesterol esters to free cholesterol (ChE/FC). Resveratrol decreased intracellular cholesterol and restored ChE/FC ratios to that of cells in healthy control plasma. Conclusions MMF and resveratrol exhibit complimentary effects on macrophages exposed to SLE plasma. Both agents combined restore cholesterol influx and efflux gene expression to that of cells treated with control plasma. Resveratrol additionally reverses cholesterol accumulation caused by SLE plasma. Further evaluation of resveratrol+MMF in atherosclerosis in SLE may lead to improved treatment.

3: INHIBITION OF THE RECEPTOR FOR ADVANCED GLYCATION END PRODUCTS RESTORES CHOLESTEROL EFFLUX IN THP-1 HUMAN MACROPHAGES EXPOSED TO PLASMA FROM TYPE 1 DIABETES MELLITUS PATIENTS

Purpose of Study Advanced glycation end products (AGE), proteins formed by nonenzymatic glycation, are prevalent in patients with diabetes mellitus (DM) and contribute to the development of atherosclerosis. We have demonstrated that plasma from patients with type 1 DM (T1DM) decreases expression of cholesterol efflux proteins in cultured THP-1 macrophages compared to healthy control (HC) plasma. Here we explore a mechanism that restores cholesterol efflux in T1DM plasma through blockade of the receptor for AGE (RAGE). Methods Used Carboxy-methyl-lysine-modified proteins (CML-MP), the most prevalent AGE in vivo, were measured in the plasma of 20 pediatric T1DM patients and 20 sex and age-matched HC by ELISA. THP-1 macrophages (106/ml) were incubated for 18 h in RPMI media in the presence of 10% plasma from each enrolled patient in triplicate±anti-RAGE antibody. Cholesterol efflux proteins: ATP binding cassette transporter (ABC)A1 and 27-hydroxylase were quantified by real-time RT-PCR using specific primers for each gene. Summary of Results The level of CML-MP was significantly elevated in T1DM plasma (1.65±1.3 ng/ml) versus HC plasma (1.05±0.4 ng/ml) (P<0.05, n=20). ABCA1 expression was significantly lower in macrophages exposed to T1DM plasma (1.108±0.8 U) versus HC plasma (1.624±0.6) (P<0.05, n=20). Exposure of THP-1 macrophages to T1DM plasma downregulated 27-hydroxylase mRNA to 1.94±0.9 U in T1DM versus 3.4±2.9 U in HC (P<0.01, n=20). Inactivation of RAGE before exposure to T1DM plasma increased ABCA1 expression by 20%. However, we observed no effect on the level of 27-hydroxylase. Conclusions We demonstrate that elevated AGE in plasma of T1DM patients inhibits cholesterol efflux and suppresses intracellular cholesterol processing via 27-hydroxylase and ABCA1 in naïve macrophages. RAGE inactivation restores mRNA level of the ABCA1 transporter, but not the 27-hydroxylase enzyme. These findings impart new targets for prevention of cardiovascular disease in DM and suggest that factors other than AGE may impact cholesterol transport.

Indications and Outcome of PPM and ICD Placement

The use of synchronized atrioventricular (AV) pacing devices and implantable cardioverter-defibrillators (ICDs) plays a critical role in the management of hypertrophic cardiomyopathy (HCM). Indications for pacing and defibrillators follow the standard guidelines for treatment of conduction disease and arrhythmias in the general population, with distinct additional indications for HCM patients based on the potential to mitigate diastolic dysfunction and outflow tract gradients and the potential to prevent and treat life-threatening ventricular arrhythmia and sudden cardiac death. ICDs can be a life-saving therapy in high-risk HCM patients, but the early placement of these devices in younger patients may expose them to a higher lifetime risk of complications. Given the unique nature of HCM, specific procedural and programming considerations should be taken into account.

INCREASED CARDIAC READMISSIONS IN PATIENTS WITH LEFT VENTRICULAR NONCOMPACTION COMPARED TO NONISCHEMIC CARDIOMYOPATHY

Left ventricular noncompaction (LVNC) is an incompletely understood form of cardiomyopathy that can lead to heart failure, ventricular arrhythmias, and sudden cardiac death; however, outcome studies in this disease are lacking. Therefore we examined patients found to have cardiomyopathy by cardiac

ASSESSMENT OF CHANGE IN CLINICAL PRACTICE USING THE UPDATED 2009 AMERICAN COLLEGE OF CARDIOLOGY/ AMERICAN SOCIETY OF NUCLEAR CARDIOLOGY FOR APPROPRIATENESS CRITERIA SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY MYOCARDIAL PERFUSION IMAGING

In 2009 the American College of Cardiology/ American Society of Nuclear Cardiology (ACC/ASNC) updated the 2005 appropriateness criteria categorizing the various indications for the performance of Single-Photon Emission Computed Tomography Myocardial Perfusion Imaging (SPECT MPI). We sought to

IMPACT OF THE UPDATED 2009 AMERICAN COLLEGE OF CARDIOLOGY/ AMERICAN SOCIETY OF NUCLEAR CARDIOLOGY APPROPRIATENESS CRITERIA FOR SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY MYOCARDIAL PERFUSION IMAGING

In 2009 the American College of Cardiology/ American Society of Nuclear Cardiology (ACC/ASNC) updated the 2005 appropriateness criteria categorizing the various indications for the performance of Single-Photon Emission Computed Tomography Myocardial Perfusion Imaging (SPECT MPI). We sought to