Muscle Cell Content Research Articles

EphA2 blockage ALW-II-41-27 alleviates atherosclerosis by remodeling gut microbiota to regulate bile acid metabolism.

Coronary artery disease (CAD), a critical condition resulting from systemic inflammation, metabolic dysfunction, and gut microbiota dysbiosis, poses a global public health challenge. ALW-II-41-27, a specific inhibitor of the EphA2 receptor, has shown anti-inflammatory prosperities. However, the impact of ALW-II-41-27 on atherosclerosis has not been elucidated. This study aimed to examine the roles of pharmacologically inhibiting EphA2 and the underlying mechanism in ameliorating atherosclerosis. ALW-II-41-27 was administered to apoE-/- mice fed a high-fat diet via intraperitoneal injection. We first discovered that ALW-II-41-27 led to a significant reduction in atherosclerotic plaques, evidenced by reduced lipid and macrophage accumulation, alongside an increase in collagen and smooth muscle cell content. ALW-II-41-27 also significantly lowered plasma and hepatic cholesterol levels, as well as the colonic inflammation. Furthermore, gut microbiota was analyzed by metagenomics and plasma metabolites by untargeted metabolomics. ALW-II-41-27-treated mice enriched Enterococcus, Akkermansia, Eggerthella and Lactobaccilus, accompanied by enhanced secondary bile acids production. To explore the causal link between ALW-II-41-27-associated gut microbiota and atherosclerosis, fecal microbiota transplantation was employed. Mice that received ALW-II-41-27-treated mouse feces exhibited the attenuated atherosclerotic plaque. In clinical, lower plasma DCA and HDCA levels were determined in CAD patients using quantitative metabolomics and exhibited a negative correlation with higher monocytes EphA2 expression. Our findings underscore the potential of ALW-II-41-27 as a novel therapeutic agent for atherosclerosis, highlighting its capacity to modulate gut microbiota composition and bile acid metabolism, thereby offering a promising avenue for CAD.

Effects of age, elastin density, and glycosaminoglycan accumulation on the delamination strength of human thoracic and abdominal aortas

Aortic dissection is a life-threatening condition caused by layer separation. Despite extensive research, the relationship between the aortic wall's structural integrity and dissection risk remains unclear. Glycosaminoglycan (GAG) accumulation and elastin loss are suspected to play significant roles. We investigated how age-related changes in aortic structure affect dissection susceptibility. Peeling tests were performed on longitudinal and circumferential thoracic (TA) and abdominal aortic (AA) strips from 35 donors aged 13–76 years (mean 38 ± 15 years, 34 % female). GAG, elastin, collagen, and smooth muscle cell (SMC) contents were assessed using bidirectional histology. Young TAs resisted longitudinal peeling better than circumferential, with delamination strengths of 65.4 mN/mm and 44.2 mN/mm, respectively. Delamination strength decreased with age in both directions, more rapidly longitudinally, equalizing at ∼20–25 mN/mm in older TAs. Delamination strength in AAs was 22 % higher than in TAs. No sex differences were observed. GAG density increased, while elastin density decreased by 2.5 % and 4 % per decade, respectively. Collagen density did not change with age, while SMC density decreased circumferentially. GAGs partially mediated the reduction in longitudinal delamination strength due to aging, while circumferential strength reduction was not mediated by changes in either GAG or elastin densities. This study explains why aortic dissections are more common in TAs, especially in older individuals, and why they typically propagate spirally. TAs exhibit lower delamination strength compared to AAs and experience strength reduction with age, a phenomenon linked to increased GAG accumulation and elastin loss. These findings enhance our understanding of the pathophysiological mechanisms behind aortic dissection. Statement of significanceThis work explores the age-dependent relationships between delamination strength in human aortas and wall structural content. We investigated 35 human aortas from donors aged 13 to 76 years, providing new insights into the biomechanical and histological factors that influence aortic dissection risk. Our findings elucidate how variations in elastin, glycosaminoglycan, collagen, and smooth muscle cell densities impact the structural integrity of the aorta, contributing significantly to the understanding of aortic dissection mechanisms.

Low to moderate dose 137Cs (γ) radiation promotes M2 type macrophage skewing and reduces atherosclerotic plaque CD68+ cell content in ApoE(−/−) mice

The effects of low doses of ionizing radiation on atherosclerosis remain uncertain, particularly as regards the generation of pro- or anti-inflammatory responses, and the time scale at which such effects can occur following irradiation. To explore these phenomena, we exposed atheroprone ApoE(−/−) mice to a single dose of 0, 0.05, 0.5 or 1 Gy of 137Cs (γ) administered at a 10.35 mGy min−1 dose rate and evaluated short-term (1–10 days) and long-term consequences (100 days). Bone marrow-derived macrophages were derived from mice 1 day after exposure. Irradiation was associated with a significant skewing of M0 and M2 polarized macrophages towards the M2 phenotype, as demonstrated by an increased mRNA expression of Retnla, Arg1, and Chil3 in cells from mice exposed to 0.5 or 1 Gy compared with non-irradiated animals. Minimal effects were noted in M1 cells or M1 marker mRNA. Concurrently, we observed a reduced secretion of IL-1β but enhanced IL-10 release from M0 and M2 macrophages. Effects of irradiation on circulating monocytes were most marked at day 10 post-exposure, when the 1 Gy dose was associated with enhanced numbers of both Ly6CHigh and Ly6Low cells. By day 100, levels of circulating monocytes in irradiated and non-irradiated mice were equivalent, but anti-inflammatory Ly6CLow monocytes were significantly increased in the spleen of mice exposed to 0.05 or 1 Gy. Long term exposures did not affect atherosclerotic plaque size or lipid content, as determined by Oil red O staining, whatever the dose applied. Similarly, irradiation did not affect atherosclerotic plaque collagen or smooth muscle cell content. However, we found that lesion CD68+ cell content tended to decrease with rising doses of radioactivity exposure, culminating in a significant reduction of plaque macrophage content at 1 Gy. Taken together, our results show that short- and long-term exposures to low to moderate doses of ionizing radiation drive an anti-inflammatory response, skewing bone marrow-derived macrophages towards an IL-10-secreting M2 phenotype and decreasing plaque macrophage content. These results suggest a low-grade athero-protective effect of low and moderate doses of ionizing radiation.

#2799 Myoglobin removal by hemadsorption: ex-vivo adsorption kinetics

Abstract Background and Aims Myoglobin, due to its molecular weight of 17 kDa and a Einstein-Stoke radius greater than expected, is classed as a middle molecular weight uremic toxin and presents a two-compartment model of distribution in the body. Rhabdomyolysis is a condition in which muscle cell content including myoglobin, are released into blood circulation due to severe injury to the muscle. Circulating myoglobin induces renal injury with several mechanisms: reduced concentration of nitric oxide in medullary renal arterioles, production of free radicals with oxidative stress, tubular necrosis as a consequence of tubular obstruction by myoglobin and cellular debris. A possible therapeutic option is the use of High Cut-off membranes but with the risk of significant loss of albumin and other proteins. The use of adsorption can overcome these limitations. The aim of our study is to assess the adsorption of myoglobin with neutral microporous styrene-divinylbenzene copolymer sorbent (e.g., HA330/380, Jafron Biomedical CO, Lts, Zhuhai City, China). Method Using a downscaled module of HA380 Cartridge, we set up an ex-vivo circulation experiment in which 1 liter of plasma containing 0.1 mg of myoglobin was pumped through the cartridge. We collected samples (3 mL) at different timepoints to measure Myoglobin concentration. We calculated the removal ratio (RR) and mass adsorbed at a given timepoints. Results Initial myoglobin concentration was 99.3 ng/ml. Final myoglobin concentration after 4 hours of experiment was 30.6 ng/ml. Removal Ratio at 4 hour was 69 % and mass adsorption of 0.068 mg of myoglobin. Conclusion To our knowledge, this is the first experiment that assessed the adsorption capacity of polystyrene-divinylbenzene sorbent. Our study, demonstrated high adsorption capacity in the first 4 hours of treatment therefore, confirming the possibility to use adsorption as an effective treatment option in rhabdomyolysis and avoiding complications associated to current dialytic treatment.

Abstract 3079: Overexpression Of Abca1 In Carotid Endothelium Of Hyperlipidemic Rabbits Decreases Vascular Inflammation

Introduction: Vascular gene therapy that reduces inflammation or increases cholesterol efflux might reduce atherosclerosis. ATP-binding cassette subfamily A member 1 (ABCA1) has both anti-inflammatory and cholesterol efflux activities. We tested whether vessel wall overexpression of ABCA1 would reduce inflammation, vessel wall lipid accumulation, and atherosclerotic lesion size. Methods: We used a helper-dependent adenoviral vector (HDAdABCA1) to overexpress ABCA1 in carotid endothelium of rabbits fed a normal or high-fat diet (HFD). Control arteries received a “Null” vector. We measured ABCA1 expression in transduced carotids of rabbits fed both diets. We used HFD-fed rabbits (n=30) to test whether HDAdABCA1 infusion reduced atherosclerosis. Measurements were made on whole carotid extracts, on extracts of laser-microdissected endothelium, and on histologic sections. Results: At 3 days after infusion, HDAdABCA1 increased whole vessel ABCA1 mRNA by ~2-fold in rabbits fed a normal diet (P=0.07) or a HFD (P=0.04). Endothelial ABCA1 protein was ~1.6-fold higher in HFD-fed rabbits (P=0.06). 24 wks after vector infusion in HFD-fed rabbits, endothelial ABCA1 mRNA was increased (46%; P=0.07), but whole vessel ABCA1 mRNA was slightly decreased (10%; P=0.004). Whole vessel CD68 expression was decreased, as were mRNA encoding several markers of M1-like macrophages: IL-1β: –44%; IL-6: –40%; MCP1: –25%; (P=0.02 for all) and M2-like macrophages: TGF-β1: –13% (P<0.001); ARG-1: –27% (P=0.03); IL-10: –23% (P=0.09). mRNA encoding IL-6 (100%; P<0.001) and TNF-α (P<0.05) was also reduced in endothelium of HDAdABCA1 arteries. Intimal/medial area ratio was slightly less in HDAdABCA1 carotids (–11%; P=0.06). Intimal lipid as well as macrophage and smooth muscle cell content were unchanged (P≥0.5 for all). Mass spectrometry showed no difference in unesterified or esterified cholesterol (P≥0.6 for both). Conclusion: ABCA1 overexpression in carotid endothelium reduced CD68 expression along with levels of several M1- and M2-like macrophage markers and inflammatory cytokines. ABCA1 overexpression had a small effect on intimal mass and did not reduce intimal lipid accumulation. ABCA1 overexpression in endothelium has mild atheroprotective effects.

Heparanase promotes the onset and progression of atherosclerosis in apolipoprotein E gene knockout mice

Background and aimsAtherosclerosis is the primary underlying cause of myocardial infarction and stroke, which are the major causes of death globally. Heparanase (Hpse) is a pro-inflammatory extracellular matrix degrading enzyme that has been implicated in atherogenesis. However, to date the precise roles of Hpse in atherosclerosis and its mechanisms of action are not well defined. This study aims to provide new insights into the contribution of Hpse in different stages of atherosclerosis in vivo. MethodsWe generated Hpse gene-deficient mice on the atherosclerosis-prone apolipoprotein E gene knockout (ApoE−/−) background to investigate the impact of Hpse gene deficiency on the initiation and progression of atherosclerosis after 6 and 14 weeks high-fat diet feeding, respectively. Atherosclerotic lesion development, blood serum profiles, lesion composition and aortic immune cell populations were evaluated. ResultsHpse-deficient mice exhibited significantly reduced atherosclerotic lesion burden in the aortic sinus and aorta at both time-points, independent of changes in plasma cholesterol levels. A significant reduction in the necrotic core size and an increase in smooth muscle cell content were also observed in advanced atherosclerotic plaques of Hpse-deficient mice. Additionally, Hpse deficiency reduced circulating and aortic levels of VCAM-1 at the initiation and progression stages of disease and circulating MCP-1 levels in the initiation but not progression stage. Moreover, the aortic levels of total leukocytes and dendritic cells in Hpse-deficient ApoE−/− mice were significantly decreased compared to control ApoE−/−mice at both disease stages. ConclusionsThis study identifies Hpse as a key pro-inflammatory enzyme driving the initiation and progression of atherosclerosis and highlighting the potential of Hpse inhibitors as novel anti-inflammatory treatments for cardiovascular disease.

A histological examination of the effects of Ferula elaeochytris extract on kidney and liver tissues in myoglobinuric acute renal failure

ABSTRACT Myoglobinuric acute renal failure (MARF) is a structural and functional disorder that occurs in the kidney following the release of muscle cell contents into the circulation. In this present study, possible protective and curative effects of Ferula elaeochytris extract against kidney and liver damage in experimentally induced MARF in a rat model were investigated. 3–4 Month-old, 200–250 g Sprague Dawley rats were divided into 8 equal groups with 7 rats per group. Group I was a no-intervention Control group. All groups except for the Group I were dehydrated for 16 hours. Following this dehydration, 50% v/v aqueous glycerol solution was injected into both hind leg muscles of the animals, at a dose of 8 ml/kg. The rats were given physiological saline (SF) once orally before the model was administered (Group II) and after the model was administered (Group V). Similarly, two different doses of Ferula elaeochytris root extract (40 mg/kg and 80 mg/kg) were dissolved in 2 ml of SF and administered orally before (Groups III and IV) and after (Group VI, VII) the model was created. Following the experimental period, kidney and liver tissues were removed from all groups, and fixed in 10% neutral formaldehyde solution for light microscopic examinations. Intracellular vacuolization, enlargement in the Bowman’s space, widespread atrophy in the tubular structures, luminal enlargement, and desquamation were detected in the kidney tissue sections of all the experimental model groups. In the liver tissue sections, was detected hepatocyte degeneration, intracellular vacuolization, irregularity in cell membrane borders, and apoptotic bodies. These histopathological consequences of MARF were evaluated for all groups, and whereas a curative effect of Ferula elaeochytris could be seen, its protective effect was higher than its curative effect.

T cell specific deletion of Casitas B lineage lymphoma-b reduces atherosclerosis, but increases plaque T cell infiltration and systemic T cell activation.

Atherosclerosis is a lipid-driven inflammatory disease of the arterial wall, and the underlying cause of the majority of cardiovascular diseases. Recent advances in high-parametric immunophenotyping of immune cells indicate that T cells constitute the major leukocyte population in the atherosclerotic plaque. The E3 ubiquitin ligase Casitas B-lymphoma proto-oncogene-B (CBL-B) is a critical intracellular regulator that sets the threshold for T cell activation, making CBL-B a potential therapeutic target to modulate inflammation in atherosclerosis. We previously demonstrated that complete knock-out of CBL-B aggravated atherosclerosis in Apoe-/- mice, which was attributed to increased macrophage recruitment and increased CD8+ T cell activation in the plaque. To further study the T cell specific role of CBL-B in atherosclerosis, Apoe-/- CD4cre Cblb fl/fl (Cbl-bcKO) mice and Apoe-/-CD4WTCblbfl/fl littermates (Cbl-bfl/fl) were fed a high cholesterol diet for ten weeks. Cbl-bcKO mice had smaller atherosclerotic lesions in the aortic arch and root compared to Cbl-bfl/fl, and a substantial increase in CD3+ T cells in the plaque. Collagen content in the plaque was decreased, while other plaque characteristics including plaque necrotic core, macrophage content, and smooth muscle cell content, remained unchanged. Mice lacking T cell CBL-B had a 1.4-fold increase in CD8+ T cells and a 1.8-fold increase in regulatory T cells in the spleen. Splenic CD4+ and CD8+ T cells had increased expression of C-X-C Motif Chemokine Receptor 3 (CXCR3) and interferon-γ (IFN-γ), indicating a T helper 1 (Th1)-like/effector CD8+ T cell-like phenotype. In conclusion, Cbl-bcKO mice have reduced atherosclerosis but show increased T cell accumulation in the plaque accompanied by systemic T cell activation.

Mapping microarchitectural degeneration in the dilated ascending aorta with ex vivo diffusion tensor imaging.

Thoracic aortic aneurysms (TAAs) carry a risk of catastrophic dissection. Current strategies to evaluate this risk entail measuring aortic diameter but do not image medial degeneration, the cause of TAAs. We sought to determine if the advanced magnetic resonance imaging (MRI) acquisition strategy, diffusion tensor imaging (DTI), could delineate medial degeneration in the ascending thoracic aorta. Porcine ascending aortas were subjected to enzyme microinjection, which yielded local aortic medial degeneration. These lesions were detected by DTI, using a 9.4 T MRI scanner, based on tensor disorientation, disrupted diffusion tracts, and altered DTI metrics. High-resolution spatial analysis revealed that fractional anisotropy positively correlated, and mean and radial diffusivity inversely correlated, with smooth muscle cell (SMC) and elastin content (P < 0.001 for all). Ten operatively harvested human ascending aorta samples (mean subject age 61.6 ± 13.3 years, diameter range 29-64 mm) showed medial pathology that was more diffuse and more complex. Nonetheless, DTI metrics within an aorta spatially correlated with SMC, elastin, and, especially, glycosaminoglycan (GAG) content. Moreover, there were inter-individual differences in slice-averaged DTI metrics. Glycosaminoglycan accumulation and elastin degradation were captured by reduced fractional anisotropy (R2 = 0.47, P = 0.043; R2 = 0.76, P = 0.002), with GAG accumulation also captured by increased mean diffusivity (R2 = 0.46, P = 0.045) and increased radial diffusivity (R2 = 0.60, P = 0.015). Ex vivo high-field DTI can detect ascending aorta medial degeneration and can differentiate TAAs in accordance with their histopathology, especially elastin and GAG changes. This non-destructive window into aortic medial microstructure raises prospects for probing the risks of TAAs beyond lumen dimensions.

Olfactory receptor 2 signaling drives experimental abdominal aortic aneurysm formation

Abstract Background Abdominal aortic aneurysms (AAA) are defined as enlargement above 3cm or 50% of its original diameter. Therapeutic options are limited to surgical and endovascular treatment, while no pharmacological interventions are available. Chronic inflammation of the vessel wall and in particularly macrophage infiltration has been associated with disease progression, leading to extensive tissue remodeling, yet the underlying mechanisms are incompletely understood. A recent study has shown extra-nasal expression of the olfactory receptor 2 (OLFR2) on vascular macrophages, in which activation induced a pro-atherogenic response. The role of macrophage OLFR2 signaling in AAA, however, is unknown. Methods &amp; Results To determine whether the OLFR2 ortholog OR6A2 is expressed in human AAA, we performed in silico micro-array analysis of human AAA tissue. OR6A2 was shown to be specifically upregulated in AAA tissue with thrombus formation compared to healthy control tissue. We confirmed OR6A2 expression on macrophages by immunofluorescence. To determine OLFR2 expression among vascular immune cells in mice, we induced AAA formation by porcine pancreas (PPE) infusion into the infrarenal aorta of C57BL6/J (WT) mice and performed spectral cytometry utilizing a 26-marker panel at baseline, day 7 and day 28. OLFR2 expression peaked at day 7 and decreased to baseline levels at day 28 particularly on pro-inflammatory monocytes, mixed resident / migratory-like macrophages and pro-inflammatory macrophages, while OLFR2 was not detectable on tissue resident-like macrophages. To assess a functional role of OLFR2 in AAA formation, we induced AAA in OLFR2-deficient (KO) mice and WT controls by PPE. Ultrasound analysis of the abdominal aorta revealed protection from AAA formation in KO mice. Histological analysis showed significantly reduced macrophage while increased smooth muscle cell content in aortic sections of KO mice compared to WT controls. This was accompanied by higher collagen content in KO mice. Additionally, plasma levels of the pro-inflammatory cytokines TNF-alpha and Interferon-gamma were significantly reduced in KO mice 28 days post PPE. Bulk transcriptome analysis corroborated these findings and indicated increased pathways associated with vascular smooth muscle cell contractility while decreased leukocyte activation in KO aortas. Conclusion We show that OLFR2 deficiency in mice attenuates abdominal aortic aneurysm development, aortic remodeling and pro-inflammatory response. OLFR2 might thus present a novel target for drug-based AAA therapies.

PCSK6 ablation increases atherosclerotic burden, but provides plaque stability by regulating TH17 and smooth muscle cell content

PCSK6 ablation increases atherosclerotic burden, but provides plaque stability by regulating TH17 and smooth muscle cell content

Neutrophil-specific STAT4 deficiency attenuates atherosclerotic burden and improves plaque stability via reduction in neutrophil activation and recruitment into aortas of Ldlr-/- mice.

Neutrophils drive atheroprogression and directly contribute to plaque instability. We recently identified signal transducer and activator of transcription 4 (STAT4) as a critical component for bacterial host defense in neutrophils. The STAT4-dependent functions of neutrophils in atherogenesis are unknown. Therefore, we investigated a contributory role of STAT4 in neutrophils during advanced atherosclerosis. We generated myeloid-specific Stat4ΔLysMLdlr-/-, neutrophil-specific Stat4ΔS100A8Ldlr-/-, and control Stat4fl/flLdlr-/- mice. All groups were fed a high-fat/cholesterol diet (HFD-C) for 28 weeks to establish advanced atherosclerosis. Aortic root plaque burden and stability were assessed histologically by Movat pentachrome staining. Nanostring gene expression analysis was performed on isolated blood neutrophils. Flow cytometry was utilized to analyze hematopoiesis and blood neutrophil activation. In vivo homing of neutrophils to atherosclerotic plaques was performed by adoptively transferring prelabeled Stat4ΔLysMLdlr-/- and Stat4fl/flLdlr-/- bone marrow cells into aged atherosclerotic Apoe-/- mice and detected by flow cytometry. STAT4 deficiency in both myeloid-specific and neutrophil-specific mice provided similar reductions in aortic root plaque burden and improvements in plaque stability via reduction in necrotic core size, improved fibrous cap area, and increased vascular smooth muscle cell content within the fibrous cap. Myeloid-specific STAT4 deficiency resulted in decreased circulating neutrophils via reduced production of granulocyte-monocyte progenitors in the bone marrow. Neutrophil activation was dampened in HFD-C fed Stat4ΔLysMLdlr-/- mice via reduced mitochondrial superoxide production, attenuated surface expression of degranulation marker CD63, and reduced frequency of neutrophil-platelet aggregates. Myeloid-specific STAT4 deficiency diminished expression of chemokine receptors CCR1 and CCR2 and impaired in vivo neutrophil trafficking to atherosclerotic aorta. Our work indicates a pro-atherogenic role for STAT4-dependent neutrophil activation and how it contributes to multiple factors of plaque instability during advanced atherosclerosis in mice.

Cationic proteins from eosinophils bind bone morphogenetic protein receptors promoting vascular calcification and atherogenesis.

Blood eosinophil count and eosinophil cationic protein (ECP) concentration are risk factors of cardiovascular diseases. This study tested whether and how eosinophils and ECP contribute to vascular calcification and atherogenesis. Immunostaining revealed eosinophil accumulation in human and mouse atherosclerotic lesions. Eosinophil deficiency in ΔdblGATA mice slowed atherogenesis with increased lesion smooth muscle cell (SMC) content and reduced calcification. This protection in ΔdblGATA mice was muted when mice received donor eosinophils from wild-type (WT), Il4-/-, and Il13-/- mice or mouse eosinophil-associated-ribonuclease-1 (mEar1), a murine homologue of ECP. Eosinophils or mEar1 but not interleukin (IL) 4 or IL13 increased the calcification of SMC from WT mice but not those from Runt-related transcription factor-2 (Runx2) knockout mice. Immunoblot analyses showed that eosinophils and mEar1 activated Smad-1/5/8 but did not affect Smad-2/3 activation or expression of bone morphogenetic protein receptors (BMPR-1A/1B/2) or transforming growth factor (TGF)-β receptors (TGFBR1/2) in SMC from WT and Runx2 knockout mice. Immunoprecipitation showed that mEar1 formed immune complexes with BMPR-1A/1B but not TGFBR1/2. Immunofluorescence double-staining, ligand binding, and Scatchard plot analysis demonstrated that mEar1 bound to BMPR-1A and BMPR-1B with similar affinity. Likewise, human ECP and eosinophil-derived neurotoxin (EDN) also bound to BMPR-1A/1B on human vascular SMC and promoted SMC osteogenic differentiation. In a cohort of 5864 men from the Danish Cardiovascular Screening trial and its subpopulation of 394 participants, blood eosinophil counts and ECP levels correlated with the calcification scores of different arterial segments from coronary arteries to iliac arteries. Eosinophils release cationic proteins that can promote SMC calcification and atherogenesis using the BMPR-1A/1B-Smad-1/5/8-Runx2 signalling pathway.

(+)-CatechinAttenuatesMultipleAtherosclerosis-Associated Processes In Vitro, Modulates Disease-Associated Risk Factors in C57BL/6J Mice and Reduces Atherogenesis in LDL Receptor Deficient Mice by Inhibiting Inflammation and Increasing Markers of Plaque Stability.

A prospective study of 34492 participants shows an inverse association between (+)-catechin intake and coronary heart disease. The effects of (+)-catechin on atherosclerosis and associated risk factors are poorly understood and are investigated. (+)-Catechin attenuates reactive oxygen species production in human macrophages, endothelial cells and vascular smooth muscle cells, chemokine-driven monocytic migration, and proliferation of human macrophages and their expression of several pro-atherogenic genes. (+)-Catechin also improves oxidized LDL-mediated mitochondrial membrane depolarization in endothelial cells and attenuates growth factor-induced smooth muscle cell migration. In C57BL/6J mice fed high fat diet (HFD) for 3 weeks, (+)-catechin attenuates plasma levels of triacylglycerol and interleukin (IL)-1β and IL-2, produces anti-atherogenic changes in liver gene expression, and reduces levels of white blood cells, myeloid-derived suppressor cells, Lin- Sca+ c-Kit+ cells, and common lymphoid progenitor cells within the bone marrow. In LDL receptor deficient mice fed HFD for 12 weeks, (+)-catechin attenuates atherosclerotic plaque burden and inflammation with reduced macrophage content and increased markers of plaque stability; smooth muscle cell and collagen content. This study provides novel, detailed insights into the cardio-protective actions of (+)-catechin together with underlying molecular mechanisms and supports further assessments of its beneficial effects in human trials.

MP27-11 CORRELATION OF PENILE GRAYSCALE PHARMACO-ULTRASONOGRAPHY WITH ERECTILE TISSUE COMPOSITION IN MEN WITH ERECTILE DYSFUNCTION

You have accessJournal of UrologyCME1 Apr 2023MP27-11 CORRELATION OF PENILE GRAYSCALE PHARMACO-ULTRASONOGRAPHY WITH ERECTILE TISSUE COMPOSITION IN MEN WITH ERECTILE DYSFUNCTION Noel Kim, Alyssa Yee, Andrew Goldstein, Sue Goldstein, and Irwin Goldstein Noel KimNoel Kim More articles by this author , Alyssa YeeAlyssa Yee More articles by this author , Andrew GoldsteinAndrew Goldstein More articles by this author , Sue GoldsteinSue Goldstein More articles by this author , and Irwin GoldsteinIrwin Goldstein More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003255.11AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Previous studies have shown that pre-operative in-office erectile function testing (pharmacocavernosometry) was correlated with erectile tissue composition (ETC) as determined by color histomorphometry on tissue samples removed during penile prosthesis insertion. Corporal veno-occlusive function (CVOF) was found to be normal at 45-50% smooth muscle cell content (SMCC). CVOF significantly worsened in an exponential relationship when SMCC was 40-25%. Below 25% SMCC, there was no recordable CVOF. We previously reported that using Grayscale pharmaco-ultrasonography (GPUS), a less invasive diagnostic assessment for ED than pharmacocavernosometry, % hypoechoic area (HA) in the corpora cavernosa (CC) negatively correlates with the erectile function domain score of the IIEF. In this study, we examined the relationship between % HA on GPUS and ETC in men with ED. METHODS: Pre-operative proximal shaft axial plane GPUS images were obtained using a 15.4 MHz probe (Aixplorer), gain setting 45%, dynamic range 70dB. % HA within the CC was assessed by computer-assisted image analysis using Image J. During penile prosthesis surgery, CC tissue from the proximal shaft was biopsied for histological analysis (n=10). Formalin-fixed (10%), paraffin-embedded tissue sections (5 µm) were stained with Masson’s trichrome. Photomicrographs were also analyzed by Image J using the Masson trichrome vector of the color deconvolution plugin. ETC was determined by assessing fractional areas of cellular content, consistent with SMCC, and extracellular matrix (ECM), consistent with erectile tissue fibrosis, from the red and blue channels, respectively. RESULTS: % HA was poorly correlated to % ECM area by linear regression analysis (r2=0.267). However, a non-linear regression model (exponential growth curve) provided a better fit (r2=0.660) with an inflection point at 40% ECM (see Figure 5). The abrupt shift is similar to the previously reported CVOF curve using pharmacocavernosometry. CONCLUSIONS: Estimation of % HA on GPUS images may be a useful, non-invasive assessment of ETC. Larger cohorts of ED patients are needed to verify the clinical utility of GPUS to predict CVOF. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e366 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Noel Kim More articles by this author Alyssa Yee More articles by this author Andrew Goldstein More articles by this author Sue Goldstein More articles by this author Irwin Goldstein More articles by this author Expand All Advertisement PDF downloadLoading ...

Desipramine enhances the stability of atherosclerotic plaque in rabbits monitored with molecular imaging.

Acid sphingomyelinase (ASM) promotes atherogenesis and acute cardiovascular events. We previously demonstrated ASM inhibitor desipramine attenuated oxidized-LDL-induced macrophage apoptosis in vitro. Here, we aim to determine whether ASM-mediated apoptosis in plaque improves stability in vivo. In this study, rabbits with abdominal aorta balloon injury and a 12-week high-cholesterol diet (HCD) were used to simulate an atherosclerotic plaque model. Atherosclerotic rabbits received oral administration of saline (Control group), atorvastatin (Ator group), or desipramine (DES group). ASM activity and ceramide level were measured by ultra-performance liquid chromatography (UPLC). Plaque morphology was assessed by histochemistry and immunohistochemistry. Apoptosis was evaluated by SPECT/CT imaging of 99mTc-duramycin uptake and TUNEL. We found that increasing ASM activity and ceramide level in atherosclerotic rabbits was abated by additional atorvastatin and desipramine treatment. Meanwhile, the DES and Ator groups were similar in plaque stability, with smaller plaque size, areas of macrophages, higher smooth muscle cell content, and decreased apoptosis and matrix metalloproteinase (MMP) activities relative to the Control group. 99mTc-duramycin uptake of rabbit aorta was significantly higher in Control than in the Normal group, while it was reduced by desipramine and atorvastatin administration. Moreover, the uptake of 99mTc-duramycin positively correlated with apoptotic cell number, macrophage infiltration, and plaque instability. The present study demonstrated that desipramine exerted plaque-stabilizing effects partially by suppressing apoptosis and MMP activity in a rabbit model. And 99mTc-duramycin SPECT/CT imaging allowed noninvasively monitoring of atherosclerotic disease and evaluation of anti-atherosclerotic therapy.

RNA-Seq Study on the Longissimus thoracis Muscle of Italian Large White Pigs Fed Extruded Linseed with or without Antioxidants and Polyphenols

The addition of n-3 polyunsaturated fatty acids (n-3 PUFAs) to the swine diet increases their content in muscle cells, and the additional supplementation of antioxidants promotes their oxidative stability. However, to date, the functionality of these components within muscle tissue is not well understood. Using a published RNA-seq dataset and a selective workflow, the study aimed to find the differences in gene expression and investigate how differentially expressed genes (DEGs) were implicated in the cellular composition and metabolism of muscle tissue of 48 Italian Large White pigs under different dietary conditions. A functional enrichment analysis of DEGs, using Cytoscape, revealed that the diet enriched with extruded linseed and supplemented with vitamin E and selenium promoted a more rapid and massive immune system response because the overall function of muscle tissue was improved, while those enriched with extruded linseed and supplemented with grape skin and oregano extracts promoted the presence and oxidative stability of n-3 PUFAs, increasing the anti-inflammatory potential of the muscular tissue.

Myeloid-restricted CD68 deficiency attenuates atherosclerosis via inhibition of ROS-MAPK-apoptosis axis

In atherosclerosis, macrophages derived from blood monocytes contribute to non-resolving inflammation, which subsequently primes necrotic core formation, and ultimately triggers acute thrombotic vascular disease. Nevertheless, little is known about how inflammatory cells, especially the macrophages fuel atherosclerosis. CD68, a unique class D scavenger receptor (SRD) family member, is specifically expressed in monocytes/macrophages and remarkably up-regulated upon oxidized low-density lipoprotein (ox-LDL) stimulation. Nonetheless, whether and how myeloid-specific CD68 affects atherosclerosis remains to be defined. To determine the essential in vivo role and mechanism linking CD68 to atherosclerosis, we engineered global and myeloid-specific CD68-deficient mice on an ApoE-null background. On Western diet, both the mice with global and the myeloid-restricted deletion of CD68 on ApoE-null background attenuated atherosclerosis, accompanied by diminished immune/inflammatory cell burden and necrotic core content, but increased smooth muscle cell content in atherosclerotic plaques. In vitro experiments revealed that CD68 deficiency in macrophages resulted in attenuated ox-LDL-induced macrophage apoptosis. Additionally, CD68 deficiency suppressed ROS production, while removal of ROS can markedly reversed this effect. We further showed that CD68 deficiency affected apoptosis through inactivation of the mitogen-activated protein kinase (MAPK) pathway. Our findings establish CD68 as a macrophage lineage-specific regulator of “ROS-MAPK-apoptosis” axis, thus providing a previously unknown mechanism for the prominence of CD68 as a risk factor for coronary artery disease. Its therapeutic inhibition may provide a potent lever to alleviate the cardiovascular disease.

The relationship between physical activity and diabetes in middle-aged and elderly people.

To investigate the association between diabetes symptoms and physical activity (PA) levels among middle-aged and older Chinese adults. Data for this study were obtained from 2018 Charles data. Z test, logistic regression analysis, and linear hierarchical regression analysis were performed in 5352 individuals aged ≥50 years with complete information. In terms of diabetes, 6.8% of the middle-aged and elderly people with diabetes were detected, and 93.2% of the middle-aged and elderly people without diabetes symptoms. The proportion of middle-aged and elderly people with high PA levels was 50.5%, and the proportion of middle-aged and elderly people with low PA was 49.5%. There was a significant positive correlation between low PA and diabetes (P < .05). After adjusting demographic characteristics (gender, registered permanent residence type, education level, age, widowhood) and health status characteristics (poor mood, asthma, hyperlipidemia, disability, memory disease, self-assessment of health status, hypertension, smoking, stroke, depression), there was still a statistical significance between PA level and diabetes (P < .05). The risk of diabetes of middle-aged and elderly people in China increases with age, while the risk of diabetes of middle-aged and elderly people with low level of PA is higher. The risk of diabetes is high among middle-aged and elderly people who are old, have poor self-evaluation health, suffer from hyperlipidemia, memory disease, and asthma. The middle-aged and old people should increase their PA levels to prevent and improve diabetes.

Arsenic causes distinct gene expression changes in macrophages polarized in vitro with either interferon-γ or interleukin-4.

Arsenic exposure is correlated with atherosclerosis in epidemiological studies and in animal models. We have previously shown that arsenic exposure enhanced the atherosclerotic plaque size, increased the plaque lipid content, and decreased the plaque smooth muscle cell and collagen contents in the apolipoprotein E knockout (apoE-/-) mice. However, the percentage of plaque-resident macrophages, the primary drivers of atherosclerosis remained unchanged. Therefore, we hypothesized that although arsenic does not change the quantity of macrophages, it alters the macrophage transcriptome towards a proatherogenic state. To test this hypothesis, we used bone marrow-derived macrophages, polarized them to either interferon-γ (IFN-ɣ) stimulated, proinflammatory or interleukin-4 (IL-4) stimulated, alternatively activated macrophages in the presence or absence of 0.67 µM (50 ppb) arsenic and performed RNA sequencing. Arsenic exposure altered the gene expression of the macrophages in a subtype-specific manner. Most differentially expressed genes (88%) were altered specifically in either IFN-ɣ- or IL-4-stimulated macrophages, whereas in the remaining 12% of genes that changed in both cell types, did so in opposite directions. In IL-4-stimulated macrophages, arsenic significantly downregulated the genes involved in cholesterol biosynthesis and the chemokines CCL17/CCL22, whereas in IFN-ɣ-stimulated macrophages, the genes associated with the liver X receptor (LXR) pathway were downregulated by arsenic. Using a bone marrow transplant experiment, we validated that the deletion of LXRα from the hematopoietic compartment rescued arsenic-enhanced atherosclerosis in the apoE-/- mouse model. Together, these data suggest that arsenic modulates subtype-specific transcriptomic changes in macrophages and further emphasize the need to define macrophage heterogeneity in atherosclerotic plaques in order to evaluate the proatherogenic role of arsenic.