The Role of Bacterial Extracellular Membrane Nanovesicles in Atherosclerosis: Unraveling a Potential Trigger.

PURPOSE OF REVIEW: In this review, we explore the intriguing and evolving connections between bacterial extracellular membrane nanovesicles (BEMNs) and atherosclerosis development, highlighting the evidence on molecular mechanisms by which BEMNs can promote the athero-inflammatory process that is central to the progression of atherosclerosis. RECENT FINDINGS: Atherosclerosis is a chronic inflammatory disease primarily driven by metabolic and lifestyle factors; however, some studies have suggested that bacterial infections may contribute to the development of both atherogenesis and inflammation in atherosclerotic lesions. In particular, the participation of BEMNs in atherosclerosis pathogenesis has attracted special attention. We provide some general insights into how the immune system responds to potential threats such as BEMNs during the development of atherosclerosis. A comprehensive understanding of contribution of BEMNs to atherosclerosis pathogenesis may lead to the development of targeted interventions for the prevention and treatment of the disease.

hTERT Peptide Fragment GV1001 Prevents the Development of Porphyromonas gingivalis-Induced Periodontal Disease and Systemic Disorders in ApoE-Deficient Mice.

GV1001, an anticancer vaccine, exhibits other biological functions, including anti-inflammatory and antioxidant activity. It also suppresses the development of ligature-induced periodontitis in mice. Porphyromonas gingivalis (Pg), a major human oral bacterium implicated in the development of periodontitis, is associated with various systemic disorders, such as atherosclerosis and Alzheimer's disease (AD). This study aimed to explore the protective effects of GV1001 against Pg-induced periodontal disease, atherosclerosis, and AD-like conditions in Apolipoprotein (ApoE)-deficient mice. GV1001 effectively mitigated the development of Pg-induced periodontal disease, atherosclerosis, and AD-like conditions by counteracting Pg-induced local and systemic inflammation, partly by inhibiting the accumulation of Pg DNA aggregates, Pg lipopolysaccharides (LPS), and gingipains in the gingival tissue, arterial wall, and brain. GV1001 attenuated the development of atherosclerosis by inhibiting vascular inflammation, lipid deposition in the arterial wall, endothelial to mesenchymal cell transition (EndMT), the expression of Cluster of Differentiation 47 (CD47) from arterial smooth muscle cells, and the formation of foam cells in mice with Pg-induced periodontal disease. GV1001 also suppressed the accumulation of AD biomarkers in the brains of mice with periodontal disease. Overall, these findings suggest that GV1001 holds promise as a preventive agent in the development of atherosclerosis and AD-like conditions associated with periodontal disease.

Impact of Probiotic Lactiplantibacillus plantarum ATCC 14917 on atherosclerotic plaque and its mechanism.

Atherosclerosis is viewed as not just as a problem of lipid build-up in blood vessels, but also as a chronic inflammatory disease involving both innate and acquired immunity. In atherosclerosis, the inflammation of the arterial walls is the key characteristic that significantly contributes to both the instability of plaque and the occlusion of arteries by blood clots. These events ultimately lead to stroke and acute coronary syndrome. Probiotics are living microorganisms that, when consumed in the right quantities, offer advantages for one's health. The primary objective of this study was to investigate the influence of Lactiplantibacillus plantarum ATCC 14917 (ATCC 14917) on the development of atherosclerotic plaques and its underlying mechanism in Apo lipoprotein E-knockout (Apoe-/- mice). In this study, Apoe-/- mice at approximately 8 weeks of age were randomly assigned to three groups: a Normal group that received a normal chow diet, a high fat diet group that received a gavage of PBS, and a Lactiplantibacillus plantarum ATCC 14917 group that received a high fat diet and a gavage of 0.2 ml ATCC 14917 (2 × 109 CFU/mL) per day for a duration of 12 weeks. Our strain effectively reduced the size of plaques in Apoe-/- mice by regulating the expression of inflammatory markers, immune cell markers, chemokines/chemokine receptors, and tight junction proteins (TJPs). Specifically, it decreased the levels of inflammatory markers (ICAM-1, CD-60 MCP-1, F4/80, ICAM-1, and VCAM-1) in the thoracic aorta, (Ccr7, cd11c, cd4, cd80, IL-1ß, TNF-α) in the colon, and increased the activity of ROS-scavenging enzymes (SOD-1 and SOD-2). It also influenced the expression of TJPs (occludin, ZO-1, claudin-3, and MUC-3). In addition, the treatment of ATCC 14917 significantly reduced the level of lipopolysaccharide in the mesenteric adipose tissue. The findings of our study demonstrated that our strain effectively decreased the size of atherosclerotic plaques by modulating inflammation, oxidative stress, intestinal integrity, and intestinal immunity.

The Gut Microbiome Affects Atherosclerosis by Regulating Reverse Cholesterol Transport.

The human system's secret organ, the gut microbiome, has received considerable attention. Emerging research has yielded substantial scientific evidence indicating that changes in gut microbial composition and microbial metabolites may contribute to the development of atherosclerotic cardiovascular disease. The burden of cardiovascular disease on healthcare systems is exacerbated by atherosclerotic cardiovascular disease, which continues to be the leading cause of mortality globally. Reverse cholesterol transport is a powerful protective mechanism that effectively prevents excessive accumulation of cholesterol for atherosclerotic cardiovascular disease. It has been revealed how the gut microbiota modulates reverse cholesterol transport in patients with atherosclerotic risk. In this review, we highlight the complex interactions between microbes, their metabolites, and their potential impacts in reverse cholesterol transport. We also explore the feasibility of modulating gut microbes and metabolites to facilitate reverse cholesterol transport as a novel therapy for atherosclerosis.

Traditional and nontraditional lipid parameters in Helicobacter pylori infection.

Aims: This study sought to evaluate the relationship between Helicobacter pylori infection and traditional and nontraditional lipid parameters, including atherogenic index of plasma, cardiogenic risk ratio, atherogenic coefficient and remnant cholesterol. Methods: After the application of exclusion criteria, 309 patients were allocated according to the absence (n = 52) or presence (n = 257) of H. pylori infection. Results: Total cholesterol, low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) levels were nonsignificantly higher, and HDL-C levels were nonsignificantly lower, in the H. pylori-infected patient group. Triglyceride-to-HDL-C ratio, LDL-C-to-HDL-C ratio, atherogenic index of plasma, cardiogenic risk ratio, atherogenic coefficient and remnant cholesterol were comparable among groups. Conclusion: There was no significant association between H. pylori infection and traditional and nontraditional novel lipid parameters and indices.

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Candida albicans accelerates atherosclerosis by activating intestinal hypoxia-inducible factor2α signaling.

The gut microbiota is closely linked to atherosclerosis. However, the role of intestinal fungi, essential members of the complex microbial community, in atherosclerosis is poorly understood. Herein, we show that gut fungi dysbiosis is implicated in patients with dyslipidemia, characterized by higher levels of Candida albicans (C. albicans), which are positively correlated with plasma total cholesterol and low-density lipoprotein-cholesterol (LDL-C) levels. Furthermore, C. albicans colonization aggravates atherosclerosis progression in a mouse model of the disease. Through gain- and loss-of-function studies, we show that an intestinal hypoxia-inducible factor 2α (HIF-2α)-ceramide pathway mediates the effect of C. albicans. Mechanistically, formyl-methionine, a metabolite of C. albicans, activates intestinal HIF-2α signaling, which drives increased ceramide synthesis to accelerate atherosclerosis. Administration of the HIF-2α selective antagonist PT2385 alleviates atherosclerosis in mice by reducing ceramide levels. Our findings identify a role for intestinal fungi in atherosclerosis progression and highlight the intestinal HIF-2α-ceramide pathway as a target for atherosclerosis treatment.

Integrating machine learning algorithms and single-cell analysis to identify gut microbiota-related macrophage biomarkers in atherosclerotic plaques.

Objective: The relationship between macrophages and the gut microbiota in patients with atherosclerosis remains poorly defined, and effective biological markers are lacking. This study aims to elucidate the interplay between gut microbial communities and macrophages, and to identify biomarkers associated with the destabilization of atherosclerotic plaques. The goal is to enhance our understanding of the underlying molecular pathways and to pave new avenues for diagnostic approaches and therapeutic strategies in the disease. Methods: This study employed Weighted Gene Co-expression Network Analysis (WGCNA) and differential expression analysis on atherosclerosis datasets to identify macrophage-associated genes and quantify the correlation between these genes and gut microbiota gene sets. The Random Forest algorithm was utilized to pinpoint PLEK, IRF8, BTK, CCR1, and CD68 as gut microbiota-related macrophage genes, and a nomogram was constructed. Based on the top five genes, a Non-negative Matrix Factorization (NMF) algorithm was applied to construct gut microbiota-related macrophage clusters and analyze their potential biological alterations. Subsequent single-cell analyses were conducted to observe the expression patterns of the top five genes and the interactions between immune cells. Finally, the expression profiles of key molecules were validated using clinical samples from atherosclerosis patients. Results: Utilizing the Random Forest algorithm, we ultimately identified PLEK, IRF8, CD68, CCR1, and BTK as gut microbiota-associated macrophage genes that are upregulated in atherosclerotic plaques. A nomogram based on the expression of these five genes was constructed for use as an auxiliary tool in clinical diagnosis. Single-cell analysis confirmed the specific expression of gut microbiota-associated macrophage genes in macrophages. Clinical samples substantiated the high expression of PLEK in unstable atherosclerotic plaques. Conclusion: Gut microbiota-associated macrophage genes (PLEK, IRF8, CD68, CCR1, and BTK) may be implicated in the pathogenesis of atherosclerotic plaques and could serve as diagnostic markers to aid patients with atherosclerosis.

The effect and mechanism of inulin on atherosclerosis is mediated by the characteristic intestinal flora and metabolites.

BACKGROUND: Inflammation and hyperlipidemia can cause atherosclerosis. Prebiotic inulin has been proven to effectively reduce inflammation and blood lipid levels. Utilizing a mouse model induced by a high-fat diet, this study aimed to explore whether the characteristic intestinal flora and its metabolites mediate the effects of inulin intervention on atherosclerosis and to clarify the specific mechanism. METHODS: Thirty apolipoprotein E-deficient (ApoE-/-) mice were randomly divided into three groups. They were fed with a normal diet, a high-fat diet or an inulin+high-fat diet for 16 weeks. The total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) in the three groups were compared. The gross aorta and aortic sinus of mice were stained with oil red O, and the area of atherosclerotic plaque was observed and compared. The diversity and structure of the mouse fecal flora were detected by sequencing the V3-V4 region of the 16S rRNA gene, and the levels of metabolites in mouse feces were assessed by gas chromatography-mass spectrometry. The plasma lipopolysaccharide (LPS) levels and aortic inflammatory factors were measured by multi-index flow cytometry (CBA). RESULTS: ApoE-/- mice fed with the high-fat diet exhibited an increase of approximately 46% in the area of atherosclerotic lesions, and the levels of TC, TG and LDL-C were significantly increased ( P < 0.05) compared with levels in the normal diet group. After inulin was added to the high-fat group, the area of atherosclerotic lesions, the level of serum LPS and aortic inflammation were reduced, and the levels of TC, TG and LDL-C were decreased ( P  < 0.05). Based on 16S rRNA gene detection, we found that the composition of the intestinal microbiota, such as Prevotella, and metabolites, such as L-arginine, changed significantly due to hyperlipidemia, and the dietary inulin intervention partially reversed the relevant changes. CONCLUSION: Inulin can inhibit the formation of atherosclerotic plaques, which may be related to the changes in lipid metabolism, the composition of the intestinal microbial community and its metabolites, and the inhibition of the expression of related inflammatory factors. Our study identified the relationships among the characteristic intestinal microbiota, metabolites and atherosclerosis, aiming to provide a new direction for future research to delay or treat atherosclerosis by changing the composition and function of the host intestinal microbiota and metabolites.

Chlamydia pneumoniae and symptomatic carotid atherosclerotic plaque: a prospective study

OBJECTIVE: To investigate the possible link between symptomatic carotid atherosclerotic plaque and Chlamydia pneumoniae. BACKGROUND: Recently, several studies have demonstrated that there may be a possible link between Chlamydia pneumonia and carotid atherosclerosis, however the real role of Chlamydia pneumoniae is not completely understood. METHOD: This is a prospective study with a total of 52 patients analyzed. All patients had been submitted to endarterectomy, and had suffered thrombotic ischemic stroke or transient ischemic attack up to 60 days prior to the surgery. Every patient presented carotid stenosis over 70 percent. The plaque was removed during the surgery and the laboratory exams were immediately done. Evaluation of Chlamydia pneumoniae DNA was done using polymerase chain reaction (PCR). RESULTS: The PCR analyses of all 52 patients were negative for Chlamydia pneumoniae. CONCLUSION: These initial results do not show a relationship between Chlamydia pneumoniae and symptomatic carotid atherosclerotic plaque.

OBJETIVO: Investigar a possível relação entre placa sintomática de carótidas e Chlamydia pneumoniae. INTRODUÇÃO: Vários estudos têm demonstrado uma possível relação entre Chlamydia pneumonia e aterosclerose carotídea, entretanto o papel definitivo da bactéria não é totalmente conhecido. Há muita especulação: poderia iniciar o processo aterosclerótico, agravá-lo ou desestabilizá-lo. MÉTODO: Estudo prospectivo com um total de 52 pacientes, endarterectomizados e previamente acometidos de acidente vascular cerebral isquêmico ou crise isquêmica transitória, em até 60 dias antes da cirurgia. Todos os pacientes apresentavam estenose carotídea superior a 70 por cento. Os testes laboratoriais foram realizados imediatamente após a endarterectomia. A Chlamydia pneumoniae foi pesquisada através de exame de DNA com reação de polimerização em cadeia (PCR). RESULTADOS: O PCR dos 52 pacientes foram negativos para Chlamydia pneumoniae. CONCLUSÃO: Estes resultados iniciais não mostram relação entre Chlamydia pneumoniae e desestabilização de placa aterosclerótica das carótidas.

Great amount of C.pneumoniae in rupture plaque vessel segments at autopsy: a comparative study with stable plaques

A possible relationship between C.pneumoniae (CP) infection, atherosclerosis and acute myocardial infarction is a debated matter. Now we performed the search of CP in histological segments of fatal ruptured plaques and of stable plaques by histochemistry (Macchiavello stain), immunohistochemistry and in situ hybridization techniques. Electron microscopy and confocal laser microscopy techniques were used in two additional cases. The semi-quantitification of CP + cells (0-4+) and quantification of lymphocytes demonstrated greater amount of CP + cells and more inflammation in the adventitia of vulnerable plaque vessel segments than of stable ones, larger amount of CP + cells in adventitia than in the plaque and high frequency of CP + cells in all groups studied. This preliminary study strongly suggests a direct pathogenetic involvement of adventitial CP in the rupture of the atheromatous plaque, development of acute myocardial infarction and also in the development of atherosclerosis.

Chlamydia pneumoniae e aterosclerose: identificaçäo do DNA bacteriano na parede arterial / Chlamydia pneumoniae and atherosclerosis: identification of bacterial DNA in the arterial wall

OBJECTIVE : The intracellular Gram-negative bacterium Chlamydia pneumoniae has been associated with atherosclerosis. The presence of Chlamydia pneumoniae has been investigated in fragments of the arterial. METHODS: Arterial fragments obtained from vascular surgical procedures in 58 patients were analyzed. From these patients, 39 were males and the mean age was 65ñ6 years. The polymerase chain reaction was used to identify the bacterial DNA with a pair of primers that codify the major outer membrane protein (MOMP) of Chlamydia pneumoniae. The amplified product was visualized by electrophoresis in the 2 porcento agarose gel stained with ethidium bromide, and it was considered positive when migrating in the band of molecular weight of the positive controls. RESULTS: Seven (12 per cent) out of the 58 patients showed positive results for Chlamydia pneumoniae. CONCLUSION: DNA from Chlamydia pneumoniae was identified in the arterial wall of a substantial number of patients with atherosclerosis. This association, which has already been described in other countries, corroborates the evidence favoring a role played by Chlamydia pneumoniae in therogenesis.

Detección de Helicobacter Pylori en placas de ateroma / Elicobacter Pilori detected in atheroma plague

Introducción: la infección y la inflamación crónica han sido implicadas como agentes etiológicos para la ateraesclerasis (ATE). Varios estudios han relacionado a la infección por H. Pylori (HP) con la EC, especialmente con los linajes mas virulentos (linaje Cag A). Objetivo: demostrar la presencia del HP en placas de endarterectomías, utilizando una técnica Inmunohistoquimica (lHQ) específica que revela una reacción Ag-Ac mediante un cromógeno. Material y Métodos: se estudiaron 34 placas ATE de distintos territorios vasculares. Se fijaron en formol descalcificándolas en ácido fórmico según necesidad. Fueron incluidos en parafina, cortados y coloreados con H-E y técnicas de IHQ específicas para HP. Luego fueron desparafinados y tratados térmicamente con una solución de recuperación antigénica (lnmuno DNA Retriever with Citrate) utilizando olla a presión. La IHQ se efectuó con un sistema de alta sensibilidad Biotina-Estreptavidina-Peroxidasa-DAB). La observación morfológica evaluó células inflamatorias mononucleares y la identificación de la bacteria en la pared o la luz vascular. Resultados: de los 34 casos estudiados, en 14 se pudo identificar el bacilo en sus diferentes formas (41,17%), asociado a signos de inflamación crónica. Conclusión: el HP estuvo presente en un número sustancial de lesiones ATE y se asoció con inflamación. Estudios recientes sugieren que la presencia de Hp, demostrada por técnicas de IHQ, potenciaría los FR para ATE, induciendo una respuesta celular inflamatoria crónica por irritación persistente de la pared arterial.

Introduction: In general, infection and chronic inflammation have be en implied as etiologic agents for atherosclerosis and in particular coronary illness (CI). Several studies have correlated the infection of Helicobacter pylori with CI, especially with virulent strains (lineage Cag A). Objective: Demonstrate the immunohistochemical presence of H. Pylori in atherosclerotic plaques obtained from endarterectomy of different vascular regions. Material and methods: 34 atherosclerotic plaques of different vascular areas were studied, (25 men and 9 women). The tissues were fixed with 10% neutral buffered-formalin and decalcifying in formic acid 5% was used when necessary. The tissue sections were included in paraffin, cut and colored with H&E and subjected to Immunohistochemistry (lHC) of H.Pylori. Briefly, tissues were deparaffinized and thermally treated with a citrate-based solution of antigenic retrieval (lmmunoDNA Retriever with Citrate, BlO SB, Santa Barbara, CA) using a water bath at 95°C for 1 hour. The IHC was conducted using a high sensitivity BiotinStreptavidin-HRP-DAB IHC system (lmmunoDetector HRPIDAB, BlO SB). The microscopic observation evaluated the' presence of mononuclear inflammatory cells and the identification of the bacteria in the wall or the vascular lumen. Results: Of the 34 cases studied 14 were positive, where one could identify the bacillus in their different forms (41, 17%) associated with chronic inflammation.

Chlamydia pneumoniae, enfermedades cardiovasculares y asma / Chlamydia pneumoniae, cardiovascular diseases and asthma

Como patógeno respiratorio, C. pneumoniae ha sido asociada con crisis de asma bronquial como uno de varios factores desencadenantes. Las evidencias seroepidemiológicas, histopatológicas y de biología molecular que relacionan además la infección por C. penumonaie con la producción de angiopatía coronaria van en aumento. Se revisan los antecedentes que han permitido encontrar esta relación, incluyendo nuestra propia experiencia, aunque se desconoce el grado de responsabilidad atribuible a la infección en esta afección degenerativa