Atherosclerosis Linked to Aberrant Amino Acid Metabolism and Immunosuppressive Amino Acid Catabolizing Enzymes

The associations between circulating amino acids and arterial aneurysms and dissection: A bidirectional Mendelian randomization study

Background

Circulating amino acid levels can be altered in arterial aneurysms and dissection, but the relationships between them is unclear. The present study investigated the causal relationship between circulating amino acid levels and arterial aneurysms and dissection via bidirectional two-sample Mendelian randomization (MR).

Methods

A bidirectional two-sample MR analysis was used. Forward analysis was performed with amino acid levels as the exposure and arterial aneurysms and dissection as outcomes. Reverse analysis was performed with arterial aneurysms and dissection as exposures and circulating amino acid levels as outcomes. MR data were analyzed using five analytical methods: the inverse-variance weighted (IVW), MR‒Egger, weighted median, simple, and weighted methods. IVW was used as the main analytical method, and the other methods were used for supplementary analyses. Heterogeneity was assessed using Cochran's Q test, and horizontal pleiotropy was assessed using intercepts from MR‒Egger regression. The genome-wide association study (GWAS) data for circulating amino acids were obtained from the IEU open GWAS database and the GWAS Catalog database. The GWAS data for arterial aneurysms and dissection were obtained from the Finngen consortium database version R10.

Results

The tyrosine level was negatively correlated with other aneurysms (P = 0.00211, OR: 0.57, 95 % CI: 0.40, 0.82). Aortic dissection decreased the circulating glycine level (P = 0.00168, OR: 0.98, 95 % CI: 0.98, 0.99).

Conclusion

Through bidirectional MR analysis, we found that tyrosine level was negatively correlated with other aneurysms and that aortic dissection reduced circulating glycine. Our findings support a possible interaction between circulating amino acid levels and arterial aneurysms and dissection.

Study on the Molecular Mechanism of XiaoXianXiong Decoction in the Treatment of Atherosclerosis Based on UHPLC-Q Exactive Focus MS/MS, Network Pharmacology, and Experimental Validation

Atherosclerosis (AS), a leading pathological basis of severe cardiovascular diseases, poses a significant threat to human health. XiaoXianXiong Decoction (XXXD), a classical traditional Chinese medicine (TCM) prescription, has demonstrated promising effects in the treatment of AS. To investigate the underlying mechanism of XXXD in treatment with AS, we used UHPLC-Q Focus MS/MS, network pharmacology and in vivo validation methods. The results showed that 59 chemical components of XXXD were identified. Network pharmacology showed that 11 key compounds, 10 key targets and five key signaling pathways involved in the therapeutic effects of XXXD on AS. Experimental verification confirmed that XXXD significantly improved dyslipidemia, lipid accumulation and pathological changes in the aorta during AS. These effects were linked to the inhibition of the PI3K/AKT signaling pathway, down-regulation of PI3K, HRAS, EGF, CREB and up-regulation of NOS3 expression. This work may provide a theoretical basis for further research on the molecular mechanisms for XXXD in AS treatment.

Perfluorooctane sulfonic acid: a possible risk factor of endothelial dysfunction based on in silico and in vitro studies

Perfluorooctane sulfonic acid (PFOS) is a fluorinated chemical utilized in a variety of industrial and household products. PFOS has been detected in human serum and is associated with multiple human adverse health effects. Epidemiological evidence has linked PFOS exposure to endothelial dysfunction, which is a key contributor to atherosclerosis. However, the underlying mechanisms of PFOS-induced endothelial dysfunction associated atherosclerosis has not been investigated. In the present study, human microvascular endothelial cells (HMEC-1) exposed to PFOS (15 μM) for 72 h, mimicking long-term exposure. We further employed integrated RNA-sequencing (RNA-seq) and transcriptomic analysis to identify differentially expressed genes (DEGs) for biological alterations: gene ontology (GO), pathway enrichment analysis (KEGG), protein-protein interaction network and modular clustering analysis. Furthermore, the Metascape database was used for disease association, tissue specificity, and transcription factor analysis. Hub genes were verified using atherosclerosis patient data sets from the GEO dataset. Alteration of hub genes in patients was then validated using immunoblotting and ELISA. Our results revealed that PFOS altered amino acid biosynthesis, lipid metabolism and induced the ER-stress response through the HRI/eIF2α/ATF4 pathway, leading to endothelial dysfunction. Interestingly, we found that PFOS induced inflammation by increasing COX-2, ICAM-1 and IL-6 expression through NF-κB and JAK2/STAT3 pathway in endothelial cells. Moreover, up-regulated C/EBPβ and ATF4 were observed in both patients and PFOS-exposed endothelium, which may use as an early biomarker and may have a potential role in PFOS-induced endothelial dysfunction. These findings provide novel insight into the underlying molecular mechanisms of PFOS-induced endothelial dysfunction associated with atherosclerosis.

Blood metabolites mediate causal inference studies on the effect of gut microbiota on the risk of vascular calcification

BACKGROUND

Emerging evidence indicates a notable connection between gut microbiota and Vascular Calcification (VC). Gut microbiota influences various disease processes through host metabolic pathways; however, the causative link between gut microbiota and VC, along with the potential mediating role of metabolites, is still not well understood.

METHODS

We leveraged data from the largest Genome-Wide Association Studies (GWAS) concerning gut microbiota, blood metabolites, and VC. To explore the causal relationships among these variables, we conducted two-sample bidirectional Mendelian Randomization (MR) analyses. Furthermore, mediation analyses were conducted to determine if metabolites act as an intermediary in the impact of gut microbiota on VC. In addition, we recruited CKD patients for mass spectrometry and CT examination, and performed a correlation analysis between the expression of blood metabolites and VC score. Finally, we experimentally validated the effects of intermediate metabolites on VC.

RESULTS

We identified 19 positive gut microbiota species and 52 positive blood metabolites with causal effects on VC. Additionally, the onset of VC was found to induce changes in the abundance of 24 gut microbiota species and 56 metabolites. Further analyses revealed that up to 13 positive gut microbiota species regulate the expression of 20 positive metabolites. Mediation analysis suggests that the gut microbiota g_KLE1615 promotes VC by downregulating the methionine-to-phosphate ratio. Mass spectrometry results indicate that over half of the metabolites identified through MR analysis show altered expression during CKD progression. Among them, 7 metabolites were significantly associated with the progression of VC. Further in vitro experiments confirmed the inhibitory effect of the intermediate metabolite methionine on VC.

CONCLUSION

Gut microbiota and blood metabolites are causally linked to VC. These findings provide a theoretical basis for microbiome- and metabolome-based therapeutic strategies for targeting VC and enhances our comprehension of the gut-vascular axis.

Integrated transcriptomic and metabolomic analysis reveals the effects of EMMPRIN on nucleotide metabolism and 1C metabolism in AS mouse BMDMs

Background

Extracellular matrix metalloproteinase inducer (EMMPRIN) has been considered as a key promoting factor in atherosclerosis (AS). Some studies have shown that regulating EMMPRIN expression in bone marrow-derived macrophages (BMDMs) of ApoE-/- mice can affect plaque stability, but the mechanism was not clear.

Methods

AS model mice were built from high-fat-feeding ApoE -/- mice, and were divided into siE group and CON group. The BMDMs and aortas from AS mice were harvested following in vivo treatment with either EMMPRIN short interfering (si)RNA (siEMMPRIN) or negative control siRNA. Transcriptomic and metabolomic profiles were analyzed using RNA-sequencing and Liquid chromatography-tandem mass spectrometry (LC-MS/MS), respectively. The efficacy of siEMMPRIN was assessed through real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting (WB). Immunofluorescence staining was employed to measure EMMPRIN expression within aortic atherosclerotic plaques. Cell proliferation was monitored using the Cell Counting Kit-8 (CCK8), while flow cytometry was utilized to analyze the cell cycle. Additionally, seahorse analysis and oil red O staining were conducted to verify glucose and lipid metabolism, respectively.

Results

A total of 3,282 differentially expressed metabolites (DEMs) and 16,138 differentially expressed genes (DEGs) were identified between the CON group and siE group. The nucleotide metabolism and one-carbon (1C) metabolism were identified as major altered pathways at both the transcriptional and metabolic levels. Metabolomic results identified increased levels of glycine, serine, betaine and S-adenosyl-L-methionine (SAM) to S-adenosyl-L-homocysteine (SAH) ratio and decreased levels of dimethylglycine (DMG) and SAH in 1C metabolism, accompanied by the accumulation of nucleotides, nucleosides, and bases in nucleotide metabolism. Transcriptomics results shown that Dnmt, Mthfd2 and Dhfr were downregulated, while Mthfr were upregulated in 1C metabolism. And numerous genes involved in de novo nucleotide synthesis, pentose phosphate pathway (PPP) and dNTP production were significantly inhibited, which may be associated with decreased BMDMs proliferation and cell cycle arrest in the G0/G1 phase in siE group. Multi-omics results also showed changes in glucose and lipid metabolism. Seahorse assay confirmed reduced glycolysis and oxidative phosphorylation (OXPHOS) levels and the Oil Red O staining confirmed the decrease of lipid droplets in siE group.

Conclusion

The integrated metabolomic and transcriptomic analysis suggested that nucleotide metabolism and 1C metabolism may be major metabolic pathways affected by siEMMPRIN in AS mouse BMDMs. Our study contributes to a better understanding of the role of EMMPRIN in AS development.

Untargeted metabolic profiling of high-dose methotrexate toxicity shows alteration in betaine metabolism

Cardiotoxicity is a well-established adverse effect of several drugs across multiple therapeutic indications. It is particularly prevalent following anticancer therapy. In order to evaluate the changes in cellular metabolism associated with methotrexate cardiotoxicity, we treated Wistar rats with a single high dose of methotrexate (HDMTX), and after five days, the animals were sacrificed. We then analyzed the cardiotoxicity parameters in serum like Cardiac enzymes(CK-MB, Troponin T, ALP), Inflammatory markers (TNF-α and IL-6), oxidative stress markers (NO, NOX-2), histopathology and cardiac tissue with the goal of identifying a metabolic signature of cardiotoxicity using discovery-based metabolomics. The biochemical parameters for cardiac enzymes, oxidative stress and inflammatory markers showed a significant increase in all three categories in rats treated with HDMTX. These findings were mirrored in the histopathological analysis confirming cardiotoxicity due to HDMTX. The results showed a total of 95 metabolites that were found to be significantly (p < 0.05) modulated: either up- or downregulated in the HDMTX-treated group when compared with the control group. Using integrated pathway analysis we found these metabolites were associated with many important cardiac tissue metabolic pathways, such as the malate aspartate shuttle, taurine and hypotaurine metabolism, betaine metabolism, spermidine biosynthesis, and homocysteine degradation. Among them, L-arginine, homocysteine, and betaine were significantly upregulated, suggesting their possible association with cardiac tissue injury. Overall, we provided evidence for using untargeted metabolomics to identify novel metabolites associated with HDMTX cardiac toxicity.

L-arginine administration exacerbates myocardial injury in diabetics via prooxidant and proinflammatory mechanisms along with myocardial structural disruption

BACKGROUND

L-arginine (L-Arg) is one of the most widely used amino acids in dietary and pharmacological products. However, the evidence on its usefulness and dose limitations, especially in diabetics is still controversial.

AIM

To investigate the effects of chronic administration of different doses of L-Arg on the cardiac muscle of type 2 diabetic rats.

METHODS

Of 96 male rats were divided into 8 groups as follows (n = 12): Control, 0.5 g/kg L-Arg, 1 g/kg L-Arg, 1.5 g/kg L-Arg, diabetic, diabetic + 0.5 g/kg L-Arg, diabetic + 1 g/kg L-Arg, and diabetic + 1.5 g/kg L-Arg; whereas L-Arg was orally administered for 3 months to all treated groups.

RESULTS

L-Arg produced a moderate upregulation of blood glucose levels to normal rats, but when given to diabetics a significant upregulation was observed, associated with increased nitric oxide, inflammatory cytokines, and malonaldehyde levels in diabetic rats treated with 1 g/kg L-Arg and 1.5 g/kg L-Arg. A substantial decrease in the antioxidant capacity, superoxide dismutase, catalase, glutathione peroxidase, reduced glutathione concentrations, and Nrf-2 tissue depletion were observed at 1 g/kg and 1.5 g/kg L-Arg diabetic treated groups, associated with myocardial injury, fibrosis, α-smooth muscle actin upregulation, and disruption of desmin cardiac myofilaments, and these effects were not noticeable at normal treated groups. On the other hand, L-Arg could significantly improve the lipid profile of diabetic rats and decrease their body weights.

CONCLUSION

L-Arg dose of 1 g/kg or more can exacerbates the diabetes injurious effects on the myocardium, while 0.5 g/kg dose can improve the lipid profile and decrease the body weight.

Immunometabolism of Tregs: mechanisms, adaptability, and therapeutic implications in diseases

Immunometabolism is an emerging field that explores the intricate interplay between immune cells and metabolism. Regulatory T cells (Tregs), which maintain immune homeostasis in immunometabolism, play crucial regulatory roles. The activation, differentiation, and function of Tregs are influenced by various metabolic pathways, such as the Mammalian targets of rapamycin (mTOR) pathway and glycolysis. Correspondingly, activated Tregs can reciprocally impact these metabolic pathways. Tregs also possess robust adaptive capabilities, thus enabling them to adapt to various microenvironments, including the tumor microenvironment (TME). The complex mechanisms of Tregs in metabolic diseases are intriguing, particularly in conditions like MASLD, where Tregs are significantly upregulated and contribute to fibrosis, while in diabetes, systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA), they show downregulation and reduced anti-inflammatory capacity. These phenomena suggest that the differentiation and function of Tregs are influenced by the metabolic environment, and imbalances in either can lead to the development of metabolic diseases. Thus, moderate differentiation and inhibitory capacity of Tregs are critical for maintaining immune system balance. Given the unique immunoregulatory abilities of Tregs, the development of targeted therapeutic drugs may position them as novel targets in immunotherapy. This could contribute to restoring immune system balance, resolving metabolic dysregulation, and fostering innovation and progress in immunotherapy.

Taurine prevents mitochondrial dysfunction and protects mitochondria from reactive oxygen species and deuterium toxicity

Taurine, although not a coding amino acid, is the most common free amino acid in the body. Taurine has multiple and complex functions in protecting mitochondria against oxidative-nitrosative stress. In this comprehensive review paper, we introduce a novel potential role for taurine in protecting from deuterium (heavy hydrogen) toxicity. This can be of crucial impact to either normal or cancer cells that have highly different mitochondrial redox status. Deuterium is an isotope of hydrogen with a neutron as well as a proton, making it about twice as heavy as hydrogen. We first explain the important role that the gut microbiome and the gut sulfomucin barrier play in deuterium management. We describe the synergistic effects of taurine in the gut to protect against the deleterious accumulation of deuterium in the mitochondria, which disrupts ATP synthesis by ATPase pumps. Moreover, taurine's derivatives, N-chlorotaurine (NCT) and N-bromotaurine (NBrT), produced through spontaneous reaction of taurine with hypochlorite and hypobromite, have fascinating regulatory roles to protect from oxidative stress and beyond. We describe how taurine could potentially alleviate deuterium stress, primarily through metabolic collaboration among various gut microflora to produce deuterium depleted nutrients and deuterium depleted water, and in this way protect against leaky gut barrier, inflammatory bowel disease, and colon cancer.

Exploring the Role of Glycine Metabolism in Coronary Artery Disease: Insights from Human Genetics and Mouse Models

Background: Circulating glycine levels have been associated with reduced risk of coronary artery disease (CAD) in humans but these associations have not been observed in all studies. We evaluated whether the relationship between glycine levels and atherosclerosis was causal using genetic analyses in humans and feeding studies in mice. Methods: Serum glycine levels were evaluated for association with risk of CAD in the UK Biobank. Genetic determinants of glycine levels were identified through a genome-wide association study (GWAS) and used to evaluate the causal relationship between glycine and risk of CAD by Mendelian randomization (MR). A dietary supplementation study was carried out with atherosclerosis-prone apolipoprotein E deficient (ApoE-/-) mice to determine the effects of increased circulating glycine levels on cardiometabolic traits and aortic lesion formation. Results: Among 105,718 UK Biobank subjects, elevated serum glycine levels were associated with significantly reduced risk of prevalent CAD (Quintile 5 vs. Quintile 1 OR = 0.76, 95% CI 0.67-0.87; p < 0.0001) and incident CAD (Quintile 5 vs. Quintile 1 HR = 0.70, 95% CI 0.65-0.77; p < 0.0001) after adjustment for age, sex, ethnicity, anti-hypertensive and lipid-lowering medications, blood pressure, kidney function, and diabetes. A GWAS meta-analysis with 230,947 subjects identified 61 loci for glycine levels, of which 26 were novel. MR analyses provided modest evidence that genetically elevated glycine levels were causally associated with reduced systolic blood pressure and risk of type 2 diabetes, but did not provide significant evidence for an association with decreased risk of CAD. Glycine supplementation in mice had no effects on cardiometabolic traits or atherosclerotic lesion development. Conclusions: While expanding the genetic architecture of glycine metabolism, MR analyses and in vivo feeding studies did not provide evidence that the clinical association of this amino acid with atherosclerosis represents a causal relationship.

The Connection Between the Oral Microbiota and the Kynurenine Pathway: Insights into Oral and Certain Systemic Disorders

The oral microbiome, comprising bacteria, fungi, viruses, and protozoa, is essential for maintaining both oral and systemic health. This complex ecosystem includes over 700 bacterial species, such as Streptococcus mutans, which contributes to dental caries through acid production that demineralizes tooth enamel. Fungi like Candida and pathogens such as Porphyromonas gingivalis are also significant, as they can lead to periodontal diseases through inflammation and destruction of tooth-supporting structures. Dysbiosis, or microbial imbalance, is a key factor in the development of these oral diseases. Understanding the composition and functions of the oral microbiome is vital for creating targeted therapies for these conditions. Additionally, the kynurenine pathway, which processes the amino acid tryptophan, plays a crucial role in immune regulation, neuroprotection, and inflammation. Oral bacteria can metabolize tryptophan, influencing the production of kynurenine, kynurenic acid, and quinolinic acid, thereby affecting the kynurenine system. The balance of microbial species in the oral cavity can impact tryptophan levels and its metabolites. This narrative review aims to explore the relationship between the oral microbiome, oral diseases, and the kynurenine system in relation to certain systemic diseases.

Blue Mussel-Derived Bioactive Peptides PIISVYWK (P1) and FSVVPSPK (P2): Promising Agents for Inhibiting Foam Cell Formation and Inflammation in Cardiovascular Diseases

Atherosclerosis is a key etiological event in the development of cardiovascular diseases (CVDs), strongly linked to the formation of foam cells. This study explored the effects of two blue mussel-derived bioactive peptides (BAPs), PIISVYWK (P1) and FSVVPSPK (P2), on inhibiting foam cell formation and mitigating inflammation in oxLDL-treated RAW264.7 macrophages. Both peptides significantly suppressed intracellular lipid accumulation and cholesterol levels while promoting cholesterol efflux by downregulating cluster of differentiation 36 (CD36) and class A1 scavenger receptors (SR-A1) and upregulating ATP binding cassette subfamily A member 1 (ABCA-1) and ATP binding cassette subfamily G member 1 (ABCG-1) expressions. The increased expression of peroxisome proliferator-activated receptor-gamma (PPAR-γ) and liver X receptor-alpha (LXR-α) further validated their role in enhancing cholesterol efflux. Additionally, P1 and P2 inhibited foam cell formation in oxLDL-treated human aortic smooth muscle cells and exerted anti-inflammatory effects by reducing pro-inflammatory cytokines, nitric oxide (NO), prostaglandin E2 (PGE2), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), primarily through inhibiting NF-κB activation. Furthermore, P1 and P2 alleviated oxidative stress by activating the Nrf2/HO-1 pathway. Our findings demonstrate that P1 and P2 have significant potential in reducing foam cell formation and inflammation, both critical factors in atherosclerosis development. These peptides may serve as promising therapeutic agents for the prevention and treatment of CVDs associated with oxidative stress and inflammation.

Complex Interplay Between Metabolism and CD4+ T-Cell Activation, Differentiation, and Function: a Novel Perspective for Atherosclerosis Immunotherapy

Atherosclerosis is a complex pathological process that results from the chronic inflammatory reaction of the blood vessel wall and involves various immune cells and cytokines. An imbalance in the proportion and function of the effector CD4+ T-cell (Teff) and regulatory T-cell (Treg) subsets is an important cause of the occurrence and development of atherosclerotic plaques. Teff cells depend on glycolytic metabolism and glutamine catabolic metabolism for energy, while Treg cells mainly rely on fatty acid oxidation (FAO), which is crucial for determining the fate of CD4+ T cells during differentiation and maintaining their respective immune functions. Here, we review recent research achievements in the field of immunometabolism related to CD4+ T cells, focusing on the cellular metabolic pathways and metabolic reprogramming involved in the activation, proliferation, and differentiation of CD4+ T cells. Subsequently, we discuss the important roles of mTOR and AMPK signaling in regulating CD4+ T-cell differentiation. Finally, we evaluated the links between CD4+ T-cell metabolism and atherosclerosis, highlighting the potential of targeted modulation of CD4+ T-cell metabolism in the prevention and treatment of atherosclerosis in the future.

Anti-atherosclerotic effect of tetrahydroxy stilbene glucoside via dual-targeting of hepatic lipid metabolisms and aortic M2 macrophage polarization in ApoE-/- mice

Tetrahydroxy stilbene glucoside (TSG) is a water-soluble natural product that has shown potential in treating atherosclerosis (AS). However, its underlying mechanisms remain unclear. Here, we demonstrate that an 8-week TSG treatment (100 mg/kg/d) significantly reduces atherosclerotic lesions and alleviates dyslipidemia symptoms in ApoE-/- mice. 1H nuclear magnetic resonance metabolomic analysis reveals differences in both lipid components and water-soluble metabolites in the livers of AS mice compared to control groups, and TSG treatment shifts the metabolic profiles of AS mice towards a normal state. At the transcriptional level, TSG significantly restores the expression of fatty acid metabolism-related genes (Srepb-1c, Fasn, Scd1, Gpat1, Dgat1, Pparα and Cpt1α), and regulates the expression levels of disturbed cholesterol metabolism-related genes (Srebp2, Hmgcr, Ldlr, Acat1, Acat2 and Cyp7a1) associated with lipid metabolism. Furthermore, at the cellular level, TSG remarkably polarizes aortic macrophages to their M2 phenotype. Our data demonstrate that TSG alleviates arthrosclerosis by dual-targeting to hepatic lipid metabolism and aortic M2 macrophage polarization in ApoE-/- mice, with significant implications for translational medicine and the treatment of AS using natural products.

Identification of metabolic components of carotid plaque in high-risk patients utilizing liquid chromatography-tandem mass spectrometry

OBJECTIVE

Carotid atherosclerosis is a chronic progressive vascular disease that can be complicated by stroke in severe cases. Prompt diagnosis and treatment of high-risk patients are quite difficult due to the lack of reliable clinical biomarkers. This study aimed to explore potential plaque metabolic markers of stroke-prone risk and relevant targets for pharmacological intervention.

METHOD

Carotid intima and plaque sample tissues were obtained from 20 patients with cerebrovascular symptoms of carotid origin. An untargeted metabolomics approach based on liquid chromatography-tandem mass spectrometry was utilized to characterize the metabolic profiles of the tissues. Multivariate and univariate analysis tools were used.

RESULTS

A total of 154 metabolites were significantly altered in carotid plaque when compared with thickened intima. Of these, 62 metabolites were upregulated, whereas 92 metabolites were downregulated. Support vector machines identified the 15 most important metabolites, such as N-(cyclopropylmethyl)-N'-phenylurea, 9(S)-HOTrE, ACar 12:2, quinoxaline-2,3-dithiol, and l-thyroxine, as biomarkers for high-risk plaques. Metabolic pathway analysis showed that abnormal purine and nucleotide metabolism, amino acid metabolism, glutathione metabolism, and vitamin metabolism may contribute to the occurrence and progression of carotid atherosclerotic plaque.

CONCLUSIONS

Our study identifies the biomarkers and related metabolic mechanisms of carotid plaque, which is stroke-prone, and provides insights and ideas for the precise prevention and targeted intervention of the disease.

Association Between Serine Concentration and Coronary Heart Disease: A Case-Control Study

Purpose

Early identification of new residual risk factors for coronary heart disease (CHD) is warranted. In this study, we aim to investigate the association between the serine concentration, an important amino acid in one-carbon metabolism, and CHD in Chinese hospitalized patients.

Patients and Methods

This case-control study included 428 case-control pairs comprising patients with CHD with a maximum coronary artery stenosis degree of >70% and controls with stenosis of <30%. The individuals were matched by age, sex, and date of coronary angiography at Peking University First Hospital from January 1, 2016, to December 31, 2019. Conditional logistic regression was used to investigate the associations between the serine concentration and CHD.

Results

Patients with CHD were aged 63.48 ± 10.38 years, and 43.73% were male. Compared with controls, patients with CHD had a slightly lower serine concentration (13.35 ± 4.20 vs 13.77 ± 4.08 μg/mL), but the difference was not significant. In the multivariable conditional logistic regression analysis, for every 1 μg/mL increase in serine concentration, the odds of CHD decreased by 6% (95% confidence interval [CI] 0.90-0.99; P = 0.010). Patients with a serine concentration of ≥13.41 μg/mL had a lower CHD risk than those with a serine concentration of <13.41 μg/mL (odds ratio [OR] 0.57, 95% CI 0.39-0.84; P = 0.004). Subgroup analyses showed that sex interacted with the relationship between serine concentration and CHD (P interaction = 0.039), which was more significant in males (OR 0.93, 95% CI 0.87-0.98; P = 0.013) than in females.

Conclusion

This study observed an inverse association between the serine concentration and CHD prevalence in Chinese hospitalized patients, which revealed that serine might play a protective role in CHD.

Duality of Branched-Chain Amino Acids in Chronic Cardiovascular Disease: Potential Biomarkers versus Active Pathophysiological Promoters

Branched-chain amino acids (BCAAs), comprising leucine (Leu), isoleucine (Ile), and valine (Val), are essential nutrients vital for protein synthesis and metabolic regulation via specialized signaling networks. Their association with cardiovascular diseases (CVDs) has become a focal point of scientific debate, with emerging evidence suggesting both beneficial and detrimental roles. This review aims to dissect the multifaceted relationship between BCAAs and cardiovascular health, exploring the molecular mechanisms and clinical implications. Elevated BCAA levels have also been linked to insulin resistance (IR), type 2 diabetes mellitus (T2DM), inflammation, and dyslipidemia, which are well-established risk factors for CVD. Central to these processes are key pathways such as mammalian target of rapamycin (mTOR) signaling, nuclear factor kappa-light-chain-enhancer of activate B cells (NF-κB)-mediated inflammation, and oxidative stress. Additionally, the interplay between BCAA metabolism and gut microbiota, particularly the production of metabolites like trimethylamine-N-oxide (TMAO), adds another layer of complexity. Contrarily, some studies propose that BCAAs may have cardioprotective effects under certain conditions, contributing to muscle maintenance and metabolic health. This review critically evaluates the evidence, addressing the biological basis and signal transduction mechanism, and also discusses the potential for BCAAs to act as biomarkers versus active mediators of cardiovascular pathology. By presenting a balanced analysis, this review seeks to clarify the contentious roles of BCAAs in CVD, providing a foundation for future research and therapeutic strategies required because of the rising prevalence, incidence, and total burden of CVDs.

Respiratory Responses to Single Oral Administration of Taurine in Sprague-Dawley Rats

Taurine is a nonessential amino acid that has been increasingly consumed due to its various beneficial biological effects. Excessive taurine intake has been linked to the positive regulation of inflammatory responses and endoplasmic reticulum stress through the modulation of intracellular calcium levels. However, research on the potential adverse effects of taurine consumption on the respiratory system is limited. To address this, we investigated the respiratory responses of 6-week-old male Sprague-Dawley rats to taurine administered orally at 0, 100, 200, and 400 mg/kg. Respiratory rate, tidal volume, and minute volume were monitored in accordance with the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) Harmonized Tripartite Guideline S7A for Safety Pharmacology Studies for Human Pharmaceuticals. We found that taurine administration did not significantly alter respiratory rate or tidal volume; however, a significant increase in minute volume was observed 6 h after administration of 200 mg/kg taurine.

SPECT-MPI for Coronary Artery Disease: A Deep Learning Approach

Background

Worldwide, coronary artery disease (CAD) is a leading cause of mortality and morbidity and remains to be a top health priority in many countries. A non-invasive imaging modality for diagnosis of CAD such as single photon emission computed tomography-myocardial perfusion imaging (SPECT-MPI) is usually requested by cardiologists as it displays radiotracer distribution in the heart reflecting myocardial perfusion. The interpretation of SPECT-MPI is done visually by a nuclear medicine physician and is largely dependent on his clinical experience and showing significant inter-observer variability.

Objective

The aim of the study is to apply a deep learning approach in the classification of SPECT-MPI for perfusion abnormalities using convolutional neural networks (CNN).

Methods

A publicly available anonymized SPECT-MPI from a machine learning repository (https://www.kaggle.com/selcankaplan/spect-mpi) was used in this study involving 192 patients who underwent stress-test-rest Tc99m MPI. An exploratory approach of CNN hyperparameter selection to search for optimum neural network model was utilized with particular focus on various dropouts (0.2, 0.5, 0.7), batch sizes (8, 16, 32, 64), and number of dense nodes (32, 64, 128, 256). The base CNN model was also compared with the commonly used pre-trained CNNs in medical images such as VGG16, InceptionV3, DenseNet121 and ResNet50. All simulations experiments were performed in Kaggle using TensorFlow 2.6.0., Keras 2.6.0, and Python language 3.7.10.

Results

The best performing base CNN model with parameters consisting of 0.7 dropout, batch size 8, and 32 dense nodes generated the highest normalized Matthews Correlation Coefficient at 0.909 and obtained 93.75% accuracy, 96.00% sensitivity, 96.00% precision, and 96.00% F1-score. It also obtained higher classification performance as compared to the pre-trained architectures.

Conclusions

The results suggest that deep learning approaches through the use of CNN models can be deployed by nuclear medicine physicians in their clinical practice to further augment their decision skills in the interpretation of SPECT-MPI tests. These CNN models can also be used as a dependable and valid second opinion that can aid physicians as a decision-support tool as well as serve as teaching or learning materials for the less-experienced physicians particularly those still in their training career. These highlights the clinical utility of deep learning approaches through CNN models in the practice of nuclear cardiology.

Metabolomics and lipidomics combined with serum pharmacochemistry uncover the potential mechanism of Huang-Lian-Jie-Du decoction alleviates atherosclerosis in ApoE-/- mice

ETHNOPHARMACOLOGICAL RELEVANCE

Atherosclerosis (AS) is one of the main cardiovascular diseases (CVDs) leading to an increase in global mortality, and its key pathological features are lipid accumulation and oxidative stress. Huang-Lian-Jie-Du decoction (HLJDD), a representative formula for clearing heat and detoxifying, has been shown to reduce aortic lipid plaque and improve AS. However, multiple components and multiple targets of HLJDD pose a challenge in comprehending its comprehensive mechanism in the treatment of AS.

AIM OF THE STUDY

This study was designed to illustrate the anti-AS mechanisms of HLJDD in an apolipoprotein E-deficient (ApoE-/-) mouse model from a metabolic perspective.

MATERIALS AND METHODS

ApoE-/- mice were kept on a high-fat diet (HFD) to induce AS. Serum total cholesterol (TC), total triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels were determined to evaluate the influence of HLJDD on dyslipidemia. Oil red O was used to stain mouse aortic lipid plaques, and hematoxylin and eosin (HE) staining was used to assess the pathological changes in the aortic roots. Metabolomics and lipidomics combined with serum pharmacochemistry were performed to research the HLJDD mechanism of alleviating AS.

RESULTS

In this study, HLJDD treatment improved serum biochemical levels and histopathological conditions in AS mice. A total of 6 metabolic pathways (arginine biosynthesis, glycerophospholipid, sphingolipid, arachidonic acid, linoleic acid, and glycerolipid metabolism) related to 25 metabolic biomarkers and 41 lipid biomarkers were clarified, and 22 prototype components migrating to blood were identified after oral administration of HLJDD.

CONCLUSION

HLJDD improved AS induced by HFD in ApoE-/- mice. The effects of HLJDD were mainly attributed to regulating lipid metabolism by regulating the metabolic pathways of glycerophospholipids, sphingolipids, arachidonic acid, linoleic acid, and glycerolipids and reducing the levels of oxidative stress by upregulating arginine biosynthesis.

Stratification of Atherosclerosis based on Plasma Metabolic States

CONTEXT

Atherosclerosis is a dominant cause of cardiovascular disease (CVD), including myocardial infarction and stroke.

OBJECTIVE

To investigate metabolic states that are associated with the development of atherosclerosis.

METHODS

Cross-sectional cohort study at a university hospital in the Netherlands. A total of 302 adult subjects with a body mass index (BMI) ≥ 27 kg/m2 were included. We integrated plasma metabolomics with clinical metadata to quantify the "atherogenic state" of each individual, providing a continuous spectrum of atherogenic states that ranges between nonatherogenic states to highly atherogenic states.

RESULTS

Analysis of groups of individuals with different clinical conditions-such as metabolically healthy individuals with obesity, and individuals with metabolic syndrome-confirmed the generalizability of this spectrum; revealed a wide variation of atherogenic states within each condition; and allowed identification of metabolites that are associated with the atherogenic state regardless of the particular condition, such as gamma-glutamyl-glutamic acid and homovanillic acid sulfate. The analysis further highlighted metabolic pathways such as catabolism of phenylalanine and tyrosine and biosynthesis of estrogens and phenylpropanoids. Using validation cohorts, we confirmed variation in atherogenic states in healthy subjects (before atherosclerosis plaques become visible), and showed that metabolites associated with the atherogenic state were also associated with future CVD.

CONCLUSION

Our results provide a global view of atherosclerosis risk states using plasma metabolomics.

Plasma Metabolic Profiling and Multiclass Diagnostic Model Development for Stable Angina Pectoris and Acute Myocardial Infarction

Coronary heart disease remains a major global health challenge, with a clear need for enhanced early risk assessment. This study aimed to elucidate metabolic signatures across various stages of coronary heart disease and develop an effective multiclass diagnostic model. Using metabolomic approaches, gas chromatography-mass and liquid chromatography-tandem mass spectrometry were used to analyze plasma samples from healthy controls, patients with stable angina pectoris, and those with acute myocardial infarction. Pathway enrichment analysis was conducted on metabolites exhibiting significant differences. The key metabolites were identified using Random Forest and Recursive Feature Elimination strategies to construct a multiclass diagnostic model. The performance of the model was validated through 10-fold cross-validation and evaluated using confusion matrices, receiver operating characteristic curves, and calibration curves. Metabolomics was used to identify 1491 metabolites, with 216, 567, and 295 distinctly present among the healthy controls, patients with stable angina pectoris, and those with acute myocardial infarction, respectively. This implicated pathways such as the glucagon signaling pathway, d-amino acid metabolism, pyruvate metabolism, and amoebiasis across various stages of coronary heart disease. After selection, testosterone isobutyrate, N-acetyl-tryptophan, d-fructose, l-glutamic acid, erythritol, and gluconic acid were identified as core metabolites in the multiclass diagnostic model. Evaluating the diagnostic model demonstrated its high discriminative ability and accuracy. This study revealed metabolic pathway perturbations at different stages of coronary heart disease, and a precise multiclass diagnostic model was established based on these findings. This study provides new insights and tools for the early diagnosis and treatment of coronary heart disease.

Determination of Serum Arginase-1 Concentrations and Serum Arginase Activity for the Non-Invasive Diagnosis of Endometriosis

Backgroud: Endometriosis remains a diagnostic challenge, both clinically and economically, affecting 6% to 15% of women of child-bearing potential. We have attempted to determine whether testing serum concentrations and activity of arginase isoenzymes could be useful for the non-invasive diagnosis of endometriosis. Methods: This study involved 180 women (105 endometriosis subjects-study group B; 22 subjects with other benign gynaecological conditions-control group 1-K1, both undergoing surgery; and 53 healthy subjects without features of endometriosis-control group 2-K2). Results: Preoperative and postoperative arginase-1 (Arg-1) concentrations were significantly higher in patients, as compared with the control groups K1 (p < 0.0001 and p = 0.0005, respectively) and K2 (both p < 0.0001). Similarly, arginase activity was significantly higher in patients than in the control group K1 before surgery and higher than in both control groups after surgery. No significant differences in either Arg-1 concentrations or arginase activity were noted between the operated control group K1 and the non-operated control group K2. A significant postoperative decrease in Arg-1 concentration was observed within both patient (p < 0.0001) and control group K1 (p = 0.0043). Diagnostic performance was assessed using the receiver operating characteristic (ROC) method. The threshold for differentiation between endometriosis patients and healthy non-operated controls was 42.3 ng/mL, with a sensitivity of 90% and specificity of 81%. For differentiation of patients and operated controls with benign gynaecological conditions, the threshold was 78.4 ng/mL, with a sensitivity of 61% and specificity of 95%. Conclusions: We, therefore, conclude that Arg-1 serum concentrations and arginase activity could be considered potential biomarkers for endometriosis but require further studies on larger cohorts of patients.

The Link between miRNAs and PCKS9 in Atherosclerosis

Cardiovascular disease (CDV) represents the major cause of death globally. Atherosclerosis, as the primary cause of CVD, is a chronic immune-inflammatory disorder with complex multifactorial pathophysiology encompassing oxidative stress, enhanced immune-inflammatory cascade, endothelial dysfunction, and thrombosis. An initiating event in atherosclerosis is the subendothelial accumulation of low-density lipoprotein (LDL), followed by the localization of macrophages to fatty deposits on blood vessel walls, forming lipid-laden macrophages (foam cells) that secrete compounds involved in plaque formation. Given the fact that foam cells are one of the key culprits that underlie the pathophysiology of atherosclerosis, special attention has been paid to the investigation of the efficient therapeutic approach to overcome the dysregulation of metabolism of cholesterol in macrophages, decrease the foam cell formation and/or to force its degradation. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a secretory serine proteinase that has emerged as a significant regulator of the lipid metabolism pathway. PCSK9 activation leads to the degradation of LDL receptors (LDLRs), increasing LDL cholesterol (LDL-C) levels in the circulation. PCSK9 pathway dysregulation has been identified as one of the mechanisms involved in atherosclerosis. In addition, microRNAs (miRNAs) are investigated as important epigenetic factors in the pathophysiology of atherosclerosis and dysregulation of lipid metabolism. This review article summarizes the recent findings connecting the role of PCSK9 in atherosclerosis and the involvement of various miRNAs in regulating the expression of PCSK9-related genes. We also discuss PCSK9 pathway-targeting therapeutic interventions based on PCSK9 inhibition, and miRNA levels manipulation by therapeutic agents.

SGLT-2 Inhibitors: The Next-generation Treatment for Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) has become a worldwide concern in recent years, primarily in highly developed Western societies. T2DM causes systemic complications, such as atherosclerotic heart disease, ischemic stroke, peripheral artery disease, kidney failure, and diabetes-related maculopathy and retinopathy. The growing number of T2DM patients and the treatment of long-term T2DM-related complications pressurize and exhaust public healthcare systems. As a result, strategies for combating T2DM and developing novel drugs are critical global public health requirements. Aside from preventive measures, which are still the most effective way to prevent T2DM, novel and highly effective therapies are emerging. In the spotlight of next-generation T2DM treatment, sodium-glucose co-transporter 2 (SGLT-2) inhibitors are promoted as the most efficient perspective therapy. SGLT-2 inhibitors (SGLT2i) include phlorizin derivatives, such as canagliflozin, dapagliflozin, empagliflozin, and ertugliflozin. SGLT-2, along with SGLT-1, is a member of the SGLT family of proteins that play a role in glucose absorption via active transport mediated by Na+/K+ ATPase. SGLT-2 is only found in the kidney, specifically the proximal tubule, and is responsible for more than 90% glucose absorption. Inhibition of SGLT-2 reduces glucose absorption, and consequently increases urinary glucose excretion, decreasing blood glucose levels. Thus, the inhibition of SGLT-2 activity ultimately alleviates T2DM-related symptoms and prevents or delays systemic T2DM-associated chronic complications. This review aimed to provide a more detailed understanding of the effects of SGLT2i responsible for the acute improvement in blood glucose regulation, a prerequisite for T2DM-associated cardiovascular complications control.

Prediction of atherosclerotic cardiovascular risk in early childhood

Atherosclerotic lesions are present even in very young individuals and therefore, risk stratification for cardiovascular (CV) disease should be implemented in childhood to promote early prevention strategies. In this review we critically appraise clinical, biochemical and genetic biomarkers available for pediatric clinical practice, which might be integrated to build effective algorithms to identify children at risk of future CV events. The first critical issue is to characterize in children aged 2-5 years, those CV risk factors/clinical conditions associated with dramatically accelerated atherosclerosis. Presence of clinical conditions such as obesity, diabetes mellitus, Kawasaki disease, etc., or positive family history for premature CV disease should be evaluated. Subsequently, a complete lipid profile and Lipoprotein(a) determination are recommended for children with increased baseline CV risk. Individuals with altered lipid profile could then undergo genetic testing for monogenic dyslipidemias to identify children with high CV genetic risk, who will be directed to appropriate therapeutic options. In perspective, calculation of a polygenic risk score, based on the analysis of several common single-nucleotide polymorphisms, could be integrated for better risk assessment. We here emphasize the importance of a "holistic" strategy integrating biochemical, anamnestic and genetic data to stratify CV risk in early childhood.

Predictive metabolites for incident myocardial infarction: a two-step meta-analysis of individual patient data from six cohorts comprising 7897 individuals from the COnsortium of METabolomics Studies

AIMS

Myocardial infarction (MI) is a major cause of death and disability worldwide. Most metabolomics studies investigating metabolites predicting MI are limited by the participant number and/or the demographic diversity. We sought to identify biomarkers of incident MI in the COnsortium of METabolomics Studies.

METHODS AND RESULTS

We included 7897 individuals aged on average 66 years from six intercontinental cohorts with blood metabolomic profiling (n = 1428 metabolites, of which 168 were present in at least three cohorts with over 80% prevalence) and MI information (1373 cases). We performed a two-stage individual patient data meta-analysis. We first assessed the associations between circulating metabolites and incident MI for each cohort adjusting for traditional risk factors and then performed a fixed effect inverse variance meta-analysis to pull the results together. Finally, we conducted a pathway enrichment analysis to identify potential pathways linked to MI. On meta-analysis, 56 metabolites including 21 lipids and 17 amino acids were associated with incident MI after adjusting for multiple testing (false discovery rate < 0.05), and 10 were novel. The largest increased risk was observed for the carbohydrate mannitol/sorbitol {hazard ratio [HR] [95% confidence interval (CI)] = 1.40 [1.26-1.56], P < 0.001}, whereas the largest decrease in risk was found for glutamine [HR (95% CI) = 0.74 (0.67-0.82), P < 0.001]. Moreover, the identified metabolites were significantly enriched (corrected P < 0.05) in pathways previously linked with cardiovascular diseases, including aminoacyl-tRNA biosynthesis.

CONCLUSIONS

In the most comprehensive metabolomic study of incident MI to date, 10 novel metabolites were associated with MI. Metabolite profiles might help to identify high-risk individuals before disease onset. Further research is needed to fully understand the mechanisms of action and elaborate pathway findings.

Effect of Genetic and Dietary Perturbation of Glycine Metabolism on Atherosclerosis in Humans and Mice

Objective

Epidemiological and genetic studies have reported inverse associations between circulating glycine levels and risk of coronary artery disease (CAD). However, these findings have not been consistently observed in all studies. We sought to evaluate the causal relationship between circulating glycine levels and atherosclerosis using large-scale genetic analyses in humans and dietary supplementation experiments in mice.

Methods

Serum glycine levels were evaluated for association with prevalent and incident CAD in the UK Biobank. A multi-ancestry genome-wide association study (GWAS) meta-analysis was carried out to identify genetic determinants for circulating glycine levels, which were then used to evaluate the causal relationship between glycine and risk of CAD by Mendelian randomization (MR). A glycine feeding study was carried out with atherosclerosis-prone apolipoprotein E deficient (ApoE-/-) mice to determine the effects of increased circulating glycine levels on amino acid metabolism, metabolic traits, and aortic lesion formation.

Results

Among 105,718 subjects from the UK Biobank, elevated serum glycine levels were associated with significantly reduced risk of prevalent CAD (Quintile 5 vs. Quintile 1 OR=0.76, 95% CI 0.67-0.87; P<0.0001) and incident CAD (Quintile 5 vs. Quintile 1 HR=0.70, 95% CI 0.65-0.77; P<0.0001) in models adjusted for age, sex, ethnicity, anti-hypertensive and lipid-lowering medications, blood pressure, kidney function, and diabetes. A meta-analysis of 13 GWAS datasets (total n=230,947) identified 61 loci for circulating glycine levels, of which 26 were novel. MR analyses provided modest evidence that genetically elevated glycine levels were causally associated with reduced systolic blood pressure and risk of type 2 diabetes, but did provide evidence for an association with risk of CAD. Furthermore, glycine-supplementation in ApoE-/- mice did not alter cardiometabolic traits, inflammatory biomarkers, or development of atherosclerotic lesions.

Conclusions

Circulating glycine levels were inversely associated with risk of prevalent and incident CAD in a large population-based cohort. While substantially expanding the genetic architecture of circulating glycine levels, MR analyses and in vivo feeding studies in humans and mice, respectively, did not provide evidence that the clinical association of this amino acid with CAD represents a causal relationship, despite being associated with two correlated risk factors.

Metabolic changes with the occurrence of atherosclerotic plaques and the effects of statins

Atherosclerosis is a common cardiovascular disease caused by the abnormal expression of multiple factors and genes influenced by both environmental and genetic factors. The primary manifestation of atherosclerosis is plaque formation, which occurs when inflammatory cells consume excess lipids, affecting their retention and modification within the arterial intima. This triggers endothelial cell (EC) activation, immune cell infiltration, vascular smooth muscle cell (VSMC) proliferation and migration, foam cell formation, lipid streaks, and fibrous plaque development. These processes can lead to vascular wall sclerosis, lumen stenosis, and thrombosis. Immune cells, ECs, and VSMCs in atherosclerotic plaques undergo significant metabolic changes and inflammatory responses. The interaction of cytokines and chemokines secreted by these cells leads to the onset, progression, and regression of atherosclerosis. The regulation of cell- or cytokine-based immune responses is a novel therapeutic approach for atherosclerosis. Statins are currently the primary pharmacological agents utilised for managing unstable plaques owing to their ability to enhance endothelial function, regulate VSMC proliferation and apoptosis by reducing cholesterol levels, and mitigate the expression and activity of inflammatory cytokines. In this review, we provide an overview of the metabolic changes associated with atherosclerosis, describe the effects of inflammatory responses on atherosclerotic plaques, and discuss the mechanisms through which statins contribute to plaque stabilisation. Additionally, we examine the role of statins in combination with other drugs in the management of atherosclerosis.

Association between dietary copper and cardiovascular disease: A narrative review

Cardiovascular disease (CVD) is a major cause of mortality and morbidity. Several studies have investigated the relationship between trace element status, including copper status, and CVDs in population studies; however, there are controversies about the role of dietary copper and CVD. We aimed to review the association between dietary copper intake with CVD and this association's related factors by reviewing both animal models and human studies. Some animal model studies have reported a strong relationship between dietary copper intake and atherogenesis based on the possible molecular pathways, whilst other studies have not confirmed this relationship. Human studies have not revealed a relationship between CVDs and dietary copper intake, but there is uncertainty about the optimal amount of dietary copper intake in relation reducing the risk of CVDs. These associations may be influenced by ethnicity, gender, underlying co-morbidities and the methods used for its measurement.

Identification of Novel Biomarkers for Early Diagnosis of Atherosclerosis Using High-Resolution Metabolomics

Atherosclerosis (AS) is a metabolic disorder and the pre-stage of several cardiovascular diseases, including myocardial infarction, stroke, and angina pectoris. Early detection of AS can provide the opportunity for effective management and better clinical results, along with the prevention of further progression of the disease. In the current study, an untargeted and targeted metabolomic approach was used to identify possible metabolic signatures that have altered levels in AS patients. A total of 200 serum samples from individuals with AS and normal were analyzed via liquid chromatography-high-resolution mass spectrometry. Univariate and multivariate analysis approaches were used to identify differential metabolites. A group of metabolites associated with bile acids, amino acids, steroid hormones, and purine metabolism were identified that are capable of distinguishing AS-risk sera from normal. Further, the targeted metabolomics approach confirmed that six metabolites, namely taurocholic acid, cholic acid, cortisol, hypoxanthine, trimethylamine N-oxide (TMAO), and isoleucine, were found to be significantly upregulated, while the concentrations of glycoursodeoxycholic acid, glycocholic acid, testosterone, leucine, methionine, phenylalanine, tyrosine, and valine were found to be significantly downregulated in the AS-risk sera. The receiver operating characteristic curves of three metabolites, including cortisol, hypoxanthine, and isoleucine, showed high sensitivity and specificity. Taken together, these findings suggest cortisol, hypoxanthine, and isoleucine as novel biomarkers for the early and non-invasive detection of AS. Thus, this study provides new insights for further investigations into the prevention and management of AS.

Long Noncoding RNA Gpr137b-ps Promotes Advanced Atherosclerosis via the Regulation of Autophagy in Macrophages

BACKGROUND

Current therapies cannot completely reverse advanced atherosclerosis. High levels of amino acids, induced by Western diet, stimulate mTORC1 (mammalian target of rapamycin complex 1)-autophagy defects in macrophages, accelerating atherosclerotic plaque progression. In addition, autophagy-lysosomal dysfunction contributes to plaque necrotic core enlargement and lipid accumulation. Therefore, it is essential to investigate the novel mechanism and molecules to reverse amino acid-mTORC1-autophagy signaling dysfunction in macrophages of patients with advanced atherosclerosis.

METHODS

We observed that Gpr137b-ps (G-protein-coupled receptor 137B, pseudogene) was upregulated in advanced atherosclerotic plaques. The effect of Gpr137b-ps on the progression of atherosclerosis was studied by generating advanced plaques in ApoE-/- mice with cardiac-specific knockout of Gpr137b-ps. Bone marrow-derived macrophages and mouse mononuclear macrophage cell line RAW264.7 cells were subjected to starvation or amino acid stimulation to study amino acid-mTORC1-autophagy signaling. Using both gain- and loss-of-function approaches, we explored the mechanism of Gpr137b-ps-regulated autophagy.

RESULTS

Our results demonstrated that Gpr137b-ps deficiency led to enhanced autophagy in macrophages and reduced atherosclerotic lesions, characterized by fewer necrotic cores and less lipid accumulation. Knockdown of Gpr137b-ps increased autophagy and prevented amino acid-induced mTORC1 signaling activation. As the downstream binding protein of Gpr137b-ps, HSC70 (heat shock cognate 70) rescued the impaired autophagy induced by Gpr137b-ps. Furthermore, Gpr137b-ps interfered with the HSC70 binding to G3BP (Ras GTPase-activating protein-binding protein), which tethers the TSC (tuberous sclerosis complex) complex to lysosomes and suppresses mTORC1 signaling. In addition to verifying that the NTF2 (nuclear transport factor 2) domain of G3BP binds to HSC70 by in vitro protein synthesis, we further demonstrated that HSC70 binds to the NTF2 domain of G3BP through its W90-F92 motif by using computational modeling.

CONCLUSIONS

These findings reveal that Gpr137b-ps plays an essential role in the regulation of macrophage autophagy, which is crucial for the progression of advanced atherosclerosis. Gpr137b-ps impairs the interaction of HSC70 with G3BP to regulate amino acid-mTORC1-autophagy signaling, and these results provide a new potential therapeutic direction for the treatment of advanced atherosclerosis.

Nitric Oxide as a Determinant of Human Longevity and Health Span

The master molecular regulators and mechanisms determining longevity and health span include nitric oxide (NO) and superoxide anion radicals (SOR). L-arginine, the NO synthase (NOS) substrate, can restore a healthy ratio between the dangerous SOR and the protective NO radical to promote healthy aging. Antioxidant supplementation orchestrates protection against oxidative stress and damage-L-arginine and antioxidants such as vitamin C increase NO production and bioavailability. Uncoupling of NO generation with the appearance of SOR can be induced by asymmetric dimethylarginine (ADMA). L-arginine can displace ADMA from the site of NO formation if sufficient amounts of the amino acid are available. Antioxidants such as ascorbic acids can scavenge SOR and increase the bioavailability of NO. The topics of this review are the complex interactions of antioxidant agents with L-arginine, which determine NO bioactivity and protection against age-related degeneration.

Machine learning approaches for biomarker discovery to predict large-artery atherosclerosis

Large-artery atherosclerosis (LAA) is a leading cause of cerebrovascular disease. However, LAA diagnosis is costly and needs professional identification. Many metabolites have been identified as biomarkers of specific traits. However, there are inconsistent findings regarding suitable biomarkers for the prediction of LAA. In this study, we propose a new method integrates multiple machine learning algorithms and feature selection method to handle multidimensional data. Among the six machine learning models, logistic regression (LR) model exhibited the best prediction performance. The value of area under the receiver operating characteristic curve (AUC) was 0.92 when 62 features were incorporated in the external validation set for the LR model. In this model, LAA could be well predicted by clinical risk factors including body mass index, smoking, and medications for controlling diabetes, hypertension, and hyperlipidemia as well as metabolites involved in aminoacyl-tRNA biosynthesis and lipid metabolism. In addition, we found that 27 features were present among the five adopted models that could provide good results. If these 27 features were used in the LR model, an AUC value of 0.93 could be achieved. Our study has demonstrated the effectiveness of combining machine learning algorithms with recursive feature elimination and cross-validation methods for biomarker identification. Moreover, we have shown that using shared features can yield more reliable correlations than either model, which can be valuable for future identification of LAA.

Early hyperlipidemia triggers metabolomic reprogramming with increased SAH, increased acetyl-CoA-cholesterol synthesis, and decreased glycolysis

To identify metabolomic reprogramming in early hyperlipidemia, unbiased metabolome was screened in four tissues from ApoE-/- mice fed with high fat diet (HFD) for 3 weeks. 30, 122, 67, and 97 metabolites in the aorta, heart, liver, and plasma, respectively, were upregulated. 9 upregulated metabolites were uremic toxins, and 13 metabolites, including palmitate, promoted a trained immunity with increased syntheses of acetyl-CoA and cholesterol, increased S-adenosylhomocysteine (SAH) and hypomethylation and decreased glycolysis. The cross-omics analysis found upregulation of 11 metabolite synthetases in ApoE‾/‾ aorta, which promote ROS, cholesterol biosynthesis, and inflammation. Statistical correlation of 12 upregulated metabolites with 37 gene upregulations in ApoE‾/‾ aorta indicated 9 upregulated new metabolites to be proatherogenic. Antioxidant transcription factor NRF2-/- transcriptome analysis indicated that NRF2 suppresses trained immunity-metabolomic reprogramming. Our results have provided novel insights on metabolomic reprogramming in multiple tissues in early hyperlipidemia oriented toward three co-existed new types of trained immunity.

Combination of Taurine and Black Pepper Extract as a Treatment for Cardiovascular and Coronary Artery Diseases

The shift in modern dietary regimens to "Western style" and sedentary lifestyles are believed to be partly responsible for the increase in the global burden of cardiovascular diseases. Natural products have been used throughout human history as treatments for a plethora of pathological conditions. Taurine and, more recently, black pepper have gained attention for their beneficial health effects while remaining non-toxic even when ingested in excess. Taurine, black pepper, and the major terpene constituents found in black pepper (i.e., β-caryophyllene; α-pinene; β-pinene; α-humulene; limonene; and sabinene) that are present in PhytoCann BP^® have been shown to have cardioprotective effects based on anti-inflammatory, antioxidative, anti-hypertensive and anti-atherosclerotic mechanisms. This comprehensive review of the literature focuses on determining whether the combination of taurine and black pepper extract is an effective natural treatment for reducing cardiovascular diseases risk factors (i.e., hypertension and hyperhomocysteinemia) and for driving anti-inflammatory, antioxidative and anti-atherosclerotic mechanisms to combat coronary artery disease, heart failure, myocardial infarction, and atherosclerotic disease.

IDO/Kynurenine; novel insight for treatment of inflammatory diseases

Inflammation and oxidative stress play pivotal roles in pathogenesis of many diseases including cancer, type 2 diabetes, cardiovascular disease, atherosclerosis, neurological diseases, and inflammatory diseases such as inflammatory bowel disease (IBD). Inflammatory mediators such as interleukins (ILs), interferons (INF-s), and tumor necrosis factor (TNF)-α are related to an extended chance of inflammatory diseases initiation or progression due to the over expression of the nuclear factor Kappa B (NF-κB), signal transducer of activators of transcription (STAT), nod-like receptor family protein 3 (NLRP), toll-like receptors (TLR), mitogen-activated protein kinase (MAPK), and mammalian target of rapamycin (mTOR) pathways. These pathways are completely interconnected. Theindoleamine 2,3 dioxygenase (IDO) subset of the kynurenine (KYN) (IDO/KYN), is a metabolic inflammatory pathway involved in production of nicotinamide adenine dinucleotide (NAD + ). It has been shown that IDO/KYN actively participates in inflammatory processes and can increase the secretion of cytokines that provoke inflammatory diseases. Data were extracted from clinical and animal studies published in English between 1990-April 2022, which were collected from PubMed, Google Scholar, Scopus, and Cochrane library. IDO/KYN is completely associated with inflammatory-related pathways, thus leading to the production of cytokines such as TNF-α, IL-1β, and IL-6, and ultimately development and progression of various inflammatory disorders. Inhibition of the IDO/KYN pathway might be a novel therapeutic option for inflammatory diseases. Herein, we gathered data on probable interactions of the IDO/KYN pathway with induction of some inflammatory diseases.

Atherosclerosis and Inflammation: Insights from the Theory of General Pathological Processes

Recent advances have greatly improved our understanding of the molecular mechanisms behind atherosclerosis pathogenesis. However, there is still a need to systematize this data from a general pathology perspective, particularly with regard to atherogenesis patterns in the context of both canonical and non-classical inflammation types. In this review, we analyze various typical phenomena and outcomes of cellular pro-inflammatory stress in atherosclerosis, as well as the role of endothelial dysfunction in local and systemic manifestations of low-grade inflammation. We also present the features of immune mechanisms in the development of productive inflammation in stable and unstable plaques, along with their similarities and differences compared to canonical inflammation. There are numerous factors that act as inducers of the inflammatory process in atherosclerosis, including vascular endothelium aging, metabolic dysfunctions, autoimmune, and in some cases, infectious damage factors. Life-critical complications of atherosclerosis, such as cardiogenic shock and severe strokes, are associated with the development of acute systemic hyperinflammation. Additionally, critical atherosclerotic ischemia of the lower extremities induces paracoagulation and the development of chronic systemic inflammation. Conversely, sepsis, other critical conditions, and severe systemic chronic diseases contribute to atherogenesis. In summary, atherosclerosis can be characterized as an independent form of inflammation, sharing similarities but also having fundamental differences from low-grade inflammation and various variants of canonical inflammation (classic vasculitis).

New insights on the cardiovascular effects of IGF-1

INTRODUCTION

Cardiovascular (CV) disorders are steadily increasing, making them the world's most prevalent health issue. New research highlights the importance of insulin-like growth factor 1 (IGF-1) for maintaining CV health.

METHODS

We searched PubMed and MEDLINE for English and non-English articles with English abstracts published between 1957 (when the first report on IGF-1 identification was published) and 2022. The top search terms were: IGF-1, cardiovascular disease, IGF-1 receptors, IGF-1 and microRNAs, therapeutic interventions with IGF-1, IGF-1 and diabetes, IGF-1 and cardiovascular disease. The search retrieved original peer-reviewed articles, which were further analyzed, focusing on the role of IGF-1 in pathophysiological conditions. We specifically focused on including the most recent findings published in the past five years.

RESULTS

IGF-1, an anabolic growth factor, regulates cell division, proliferation, and survival. In addition to its well-known growth-promoting and metabolic effects, there is mounting evidence that IGF-1 plays a specialized role in the complex activities that underpin CV function. IGF-1 promotes cardiac development and improves cardiac output, stroke volume, contractility, and ejection fraction. Furthermore, IGF-1 mediates many growth hormones (GH) actions. IGF-1 stimulates contractility and tissue remodeling in humans to improve heart function after myocardial infarction. IGF-1 also improves the lipid profile, lowers insulin levels, increases insulin sensitivity, and promotes glucose metabolism. These findings point to the intriguing medicinal potential of IGF-1. Human studies associate low serum levels of free or total IGF-1 with an increased risk of CV and cerebrovascular illness. Extensive human trials are being conducted to investigate the therapeutic efficacy and outcomes of IGF-1-related therapy.

DISCUSSION

We anticipate the development of novel IGF-1-related therapy with minimal side effects. This review discusses recent findings on the role of IGF-1 in the cardiovascular (CVD) system, including both normal and pathological conditions. We also discuss progress in therapeutic interventions aimed at targeting the IGF axis and provide insights into the epigenetic regulation of IGF-1 mediated by microRNAs.

High prevalence of lower limb atherosclerosis is linked with the gut-liver axis in patients with primary biliary cholangitis

BACKGROUND AND AIMS

Hypercholesterolemia is frequent in people with primary biliary cholangitis (PBC); however, it does not seem to confer an increased risk of cardiovascular disease. We aimed to evaluate the prevalence of peripheral arterial disease in PBC women and its association with the gut-liver axis and systemic inflammation.

METHODS

Thirty patients affected by PBC and hypercholesterolemia were enrolled, with equal-sized groups of women with non-alcoholic fatty liver disease (NAFLD) and healthy controls (CTRL). All patients underwent Doppler ultrasound examination of peripheral arteries, assessment of flow-mediated dilation, quantification of circulating cytokines and vasoactive mediators and characterization of the gut microbiota.

RESULTS

PBC patients had a higher prevalence of lower extremity arterial disease (LEAD) defined as atherosclerotic plaques in any of femoral, popliteal and/or tibial arteries compared with both NAFLD and CTRL women (83.3% vs. 53.3% and 50%, respectively; p = .01). Factors associated with LEAD at univariate analysis were VCAM-1 (p = .002), ICAM-1 (p = .003), and TNF-alpha (p = .04) serum levels, but only VCAM-1 (OR 1.1, 95% CI 1.0-1.1; p = .04) and TNF-alpha (OR 1.12, 95% CI 0.99-1.26; p = .04) were confirmed as independent predictors in the multivariate model. Gut microbiota analysis revealed that Acidaminococcus (FDR = 0.0008), Bifidobacterium (FDR = 0.001) and Oscillospira (FDR = 0.03) were differentially expressed among groups. Acidaminococcus, which was increased in PBC, was positively correlated with TNF-alpha serum levels. Down-regulation of metabolic pathways linked to fatty acid and butyrate metabolism, glyoxylate metabolism and branched-chain amino acids degradation was found in the functional gut metagenome of PBC women.

CONCLUSIONS

LEAD is common in patients affected by PBC and is associated with inflammatory markers and alterations in the gut-liver axis.

Targeting mitochondrial impairment for the treatment of cardiovascular diseases: From hypertension to ischemia-reperfusion injury, searching for new pharmacological targets

Mitochondria and mitochondrial proteins represent a group of promising pharmacological target candidates in the search of new molecular targets and drugs to counteract the onset of hypertension and more in general cardiovascular diseases (CVDs). Indeed, several mitochondrial pathways result impaired in CVDs, showing ATP depletion and ROS production as common traits of cardiac tissue degeneration. Thus, targeting mitochondrial dysfunction in cardiomyocytes can represent a successful strategy to prevent heart failure. In this context, the identification of new pharmacological targets among mitochondrial proteins paves the way for the design of new selective drugs. Thanks to the advances in omics approaches, to a greater availability of mitochondrial crystallized protein structures and to the development of new computational approaches for protein 3D-modelling and drug design, it is now possible to investigate in detail impaired mitochondrial pathways in CVDs. Furthermore, it is possible to design new powerful drugs able to hit the selected pharmacological targets in a highly selective way to rescue mitochondrial dysfunction and prevent cardiac tissue degeneration. The role of mitochondrial dysfunction in the onset of CVDs appears increasingly evident, as reflected by the impairment of proteins involved in lipid peroxidation, mitochondrial dynamics, respiratory chain complexes, and membrane polarization maintenance in CVD patients. Conversely, little is known about proteins responsible for the cross-talk between mitochondria and cytoplasm in cardiomyocytes. Mitochondrial transporters of the SLC25A family, in particular, are responsible for the translocation of nucleotides (e.g., ATP), amino acids (e.g., aspartate, glutamate, ornithine), organic acids (e.g. malate and 2-oxoglutarate), and other cofactors (e.g., inorganic phosphate, NAD⁺, FAD, carnitine, CoA derivatives) between the mitochondrial and cytosolic compartments. Thus, mitochondrial transporters play a key role in the mitochondria-cytosol cross-talk by leading metabolic pathways such as the malate/aspartate shuttle, the carnitine shuttle, the ATP export from mitochondria, and the regulation of permeability transition pore opening. Since all these pathways are crucial for maintaining healthy cardiomyocytes, mitochondrial carriers emerge as an interesting class of new possible pharmacological targets for CVD treatments.

Hematological parameters and early-onset coronary artery disease: a retrospective case-control study based on 3366 participants

BACKGROUND

Thrombosis and inflammation are crucial elements in the pathogenesis of cardiovascular disease. Hematological parameters elucidate information involving the inflammatory and blood coagulation processes.

OBJECTIVES

The current study explored the association of hematological parameters with EOCAD to identify specific risk factors.

DESIGN

A single-center retrospective case-control study was conducted with 1693 coronary artery disease patients and 1693 controls.

METHODS

Hematological parameters were examined through an automated analyzer.

RESULTS

The basophil percentage was significantly reduced in EOCAD (0.43 ± 0.26, p < 0.001) and MI (0.33 ± 0.24, p < 0.001) groups compared with controls (0.54 ± 0.28). The eosinophil percentage was also significantly lower in EOCAD (2.21 ± 1.71, p < 0.001) and MI (1.71 ± 2.44, p < 0.001) groups compared with controls (2.41 ± 1.75). The lymphocyte percentage in patients of EOCAD and MI and controls was 31.65 ± 7.93, 25.48 ± 9.43, and 34.82 ± 7.28, respectively. A significant difference was observed among the groups (p < 0.001). Except for the mean corpuscular hemoglobin (MCH), other red blood cell (RBC) parameters significantly differed between EOCAD patients and controls. The red blood cell distribution width (RDW), hematocrit (HCT), RBC count, mean corpuscular hemoglobin concentration (MCHC), mean corpuscular volume (MCV), and hemoglobin level were associated with EOCAD prevalence after adjusting for baseline differences. Platelet volume distribution width (PDW) also correlated with EOCAD prevalence (ORadjust = 1.087, 95% CI: 1.044-1.131).

CONCLUSIONS

Hematological parameters are closely associated with EOCAD. Moreover, leukocyte parameters correlated with the presence and severity of the disease. In addition, erythrocyte parameters were associated with the disease presence but not with the disease severity. Among the platelet parameters, only PDW was related to the disease presence.

The interplay between nonalcoholic fatty liver disease and atherosclerotic cardiovascular disease

Therapeutic approaches that lower circulating low-density lipoprotein (LDL)-cholesterol significantly reduced the burden of cardiovascular disease over the last decades. However, the persistent rise in the obesity epidemic is beginning to reverse this decline. Alongside obesity, the incidence of nonalcoholic fatty liver disease (NAFLD) has substantially increased in the last three decades. Currently, approximately one third of world population is affected by NAFLD. Notably, the presence of NAFLD and particularly its more severe form, nonalcoholic steatohepatitis (NASH), serves as an independent risk factor for atherosclerotic cardiovascular disease (ASCVD), thus, raising interest in the relationship between these two diseases. Importantly, ASCVD is the major cause of death in patients with NASH independent of traditional risk factors. Nevertheless, the pathophysiology linking NAFLD/NASH with ASCVD remains poorly understood. While dyslipidemia is a common risk factor underlying both diseases, therapies that lower circulating LDL-cholesterol are largely ineffective against NASH. While there are no approved pharmacological therapies for NASH, some of the most advanced drug candidates exacerbate atherogenic dyslipidemia, raising concerns regarding their adverse cardiovascular consequences. In this review, we address current gaps in our understanding of the mechanisms linking NAFLD/NASH and ASCVD, explore strategies to simultaneously model these diseases, evaluate emerging biomarkers that may be useful to diagnose the presence of both diseases, and discuss investigational approaches and ongoing clinical trials that potentially target both diseases.

Systematic analysis of relationships between plasma branched-chain amino acid concentrations and cardiometabolic parameters: an association and Mendelian randomization study

BACKGROUND

Branched-chain amino acids (BCAAs; valine, leucine, and isoleucine) are essential amino acids that are associated with an increased risk of cardiometabolic diseases (CMD). However, there are still only limited insights into potential direct associations between BCAAs and a wide range of CMD parameters, especially those remaining after correcting for covariates and underlying causal relationships.

METHODS

To shed light on these relationships, we systematically characterized the associations between plasma BCAA concentrations and a large panel of 537 CMD parameters (including atherosclerosis-related parameters, fat distribution, plasma cytokine concentrations and cell counts, circulating concentrations of cardiovascular-related proteins and plasma metabolites) in 1400 individuals from the Dutch population cohort LifeLines DEEP and 294 overweight individuals from the 300OB cohort. After correcting for age, sex, and BMI, we assessed associations between individual BCAAs and CMD parameters. We further assessed the underlying causality using Mendelian randomization.

RESULTS

A total of 838 significant associations were detected for 409 CMD parameters. BCAAs showed both common and specific associations, with the most specific associations being detected for isoleucine. Further, we found that obesity status substantially affected the strength and direction of associations for valine, which cannot be corrected for using BMI as a covariate. Subsequent univariable Mendelian randomization (UVMR), after removing BMI-associated SNPs, identified seven significant causal relationships from four CMD traits to BCAA levels, mostly for diabetes-related parameters. However, no causal effects of BCAAs on CMD parameters were supported.

CONCLUSIONS

Our cross-sectional association study reports a large number of associations between BCAAs and CMD parameters. Our results highlight some specific associations for isoleucine, as well as obesity-specific effects for valine. MR-based causality analysis suggests that altered BCAA levels can be a consequence of diabetes and alteration in lipid metabolism. We found no MR evidence to support a causal role for BCAAs in CMD. These findings provide evidence to (re)evaluate the clinical importance of individual BCAAs in CMD diagnosis, prevention, and treatment.

Glutathione: A Samsonian life-sustaining small molecule that protects against oxidative stress, ageing and damaging inflammation

Many local and systemic diseases especially diseases that are leading causes of death globally like chronic obstructive pulmonary disease, atherosclerosis with ischemic heart disease and stroke, cancer and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing coronavirus disease 19 (COVID-19), involve both, (1) oxidative stress with excessive production of reactive oxygen species (ROS) that lower glutathione (GSH) levels, and (2) inflammation. The GSH tripeptide (γ- L-glutamyl-L-cysteinyl-glycine), the most abundant water-soluble non-protein thiol in the cell (1-10 mM) is fundamental for life by (a) sustaining the adequate redox cell signaling needed to maintain physiologic levels of oxidative stress fundamental to control life processes, and (b) limiting excessive oxidative stress that causes cell and tissue damage. GSH activity is facilitated by activation of the Kelch-like ECH-associated protein 1 (Keap1)-Nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) redox regulator pathway, releasing Nrf2 that regulates expression of genes controlling antioxidant, inflammatory and immune system responses. GSH exists in the thiol-reduced (>98% of total GSH) and disulfide-oxidized (GSSG) forms, and the concentrations of GSH and GSSG and their molar ratio are indicators of the functionality of the cell. GSH depletion may play a central role in inflammatory diseases and COVID-19 pathophysiology, host immune response and disease severity and mortality. Therapies enhancing GSH could become a cornerstone to reduce severity and fatal outcomes of inflammatory diseases and COVID-19 and increasing GSH levels may prevent and subdue these diseases. The life value of GSH makes for a paramount research field in biology and medicine and may be key against systemic inflammation and SARS-CoV-2 infection and COVID-19 disease. In this review, we emphasize on (1) GSH depletion as a fundamental risk factor for diseases like chronic obstructive pulmonary disease and atherosclerosis (ischemic heart disease and stroke), (2) importance of oxidative stress and antioxidants in SARS-CoV-2 infection and COVID-19 disease, (3) significance of GSH to counteract persistent damaging inflammation, inflammaging and early (premature) inflammaging associated with cell and tissue damage caused by excessive oxidative stress and lack of adequate antioxidant defenses in younger individuals, and (4) new therapies that include antioxidant defenses restoration.

Ginsenoside Rc ameliorated atherosclerosis via regulating gut microbiota and fecal metabolites

Atherosclerosis (AS) and the accompanied cardiovascular diseases (CVDs) were the leading cause of death worldwide. Recently, the association between CVDs, gut microbiota, and metabolites had aroused increasing attention. In the study, we headed our investigation into the underlying mechanism of ginsenoside Rc (GRc), an active ingredient of ginsenosides used for the treatment of CVDs, in apolipoprotein E-deficient (ApoE^−/−) mice with high-fat diet (HFD). Seven-week-old male ApoE^−/− mice were randomly divided into four groups: the normal control (NC) group, the HFD group, the GRc group (40 mg/kg/d), and the atorvastatin (Ato) group (10 mg/kg/d). Atherosclerotic injury was evaluated by aortic lesions, serum lipid levels, and inflammatory factors. The composition of gut microbiota and fecal metabolite profile were analyzed using 16S rRNA sequence and untargeted metabolomics, respectively. The results showed that GRc significantly alleviated HFD-induced aortic lesions, reduced serum levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), tumor necrosis factor-α (TNF-α), and interleukin (IL)-6 and IL-1β, and increased high-density lipoprotein cholesterol (HFD-C) level, as well as the alteration of gut microbiota composition, function, and metabolite profile. GRc also reversed HFD change of Bacteroidetes and Firmicutes at the phylum level, Muribaculaceae, Lactobacillus, Ileibacterium, Bifidobacterium, Faecalibaculum, Oscillibacter, Blautia, and Eubacterium_coprostanoligenes_group at the genus level, and 23 key metabolites involved in taurine and hypotaurine metabolism, arginine biosynthesis, ATP-binding cassette (ABC) transporters, primary bile acid biosynthesis, purine metabolism, tricarboxylic acid (TCA) cycle, and glucagon signaling pathways. Additionally, eight differential intestinal floras at the genus level were associated with 23 key differential metabolites involving atherosclerotic injury. In conclusion, our results demonstrated that GRc ameliorated atherosclerotic injury, regulated microbial and metabolomic changes in HFD-induced ApoE^−/− mice, and suggested a potential correlation among gut microbiota, metabolites, and atherosclerotic injury regarding the mechanisms of GRc against AS.

Effects of serum branched-chain amino acids on nonalcoholic fatty liver disease and subsequent cardiovascular disease

BACKGROUND

To reveal the role of branched-chain amino acids (BCAAs) in the development and progression of nonalcoholic fatty liver disease (NAFLD) and the effect on the incidence of subsequent cardiovascular disease.

METHODS

A total of 1302 subjects in the cohort study of the Huai'an Diabetes Prevention Program were divided into two groups according to whether NAFLD was present at baseline. The group without NAFLD at baseline was only followed up, and the group with NAFLD at baseline received diet and exercise interventions. Anthropometric and biochemical examinations were performed at baseline and at the end of 4 years for all subjects. Serum BCAA (leucine, isoleucine, and valine) levels were measured by hydrophilic interaction chromatography-tandem mass spectrometry. The associations of baseline serum BCAA levels with the risk for NAFLD, coronary heart disease (CHD), and cardiovascular events (CVEs) after 4 years were further evaluated.

RESULTS

(1) At baseline and after the 4-year follow-up, baseline serum leucine, valine, and total BCAAs in the NAFLD group were significantly higher than those in the non-NAFLD group (p < 0.05). (2) According to whether NAFLD was present at baseline and after follow-up, all subjects were divided into four groups, including the control group, new case group, improvement group, and unchanged group. There was no significant difference in baseline BCAAs levels between the new case group and the improvement group (p > 0.05). (3) Risk factors for the occurrence and development of NAFLD were analysed by a multiple logistic regression model according to whether NAFLD existed at baseline. Serum leucine (OR = 1.058, 95% CI 1.005-1.114, p = 0.033) and total BCAAs (OR = 1.023, 95% CI 1.001-1.046, p = 0.045) were independent risk factors for new-onset NAFLD. Serum valine (OR = 1.131, 95% CI 1.043-1.226, p = 0.003), and total BCAAs (OR = 1.040, 95% CI 1.003-1.078, p = 0.035) were independent risk factors showing that NAFLD could not be reversed. (4) The cross-table Chi-square test showed that the incidence of both CHD and CVEs was significantly highest in the new case group (p < 0.05). (5) After adjusting for confounding factors, baseline isoleucine, valine, and BCAA levels were independently associated with new-onset CHD in subjects with or without NAFLD at baseline (p < 0.05).

CONCLUSIONS

High BCAA levels exacerbate the risk of CHD and CVEs by influencing the occurrence and progression of NAFLD. However, lifestyle interventions could reverse the risk of NAFLD, CHD and CVEs associated with BCAAs.

Anti-atherosclerotic Effects of Myrtenal in High-Fat Diet-Induced Atherosclerosis in Rats

The major cause of death worldwide is atherosclerosis-related cardiovascular disease (ACD). Myrtenal was studied to determine control rats were given standard diets and a high-fat diet was given to AS model groups. Atherosclerosis-related cardiovascular disease (ACD) is globally attributed to being a predominant cause of mortality. While the beneficial effects of Myrtenal, the monoterpene from natural compounds, are increasingly being acknowledged, its anti-atherosclerotic activity has not been demonstrated clearly. The present study is proposed to determine the anti-atherosclerotic activity of Myrtenal in high-fat diet-induced atherosclerosis (AS) rat models. Control groups were maintained with standard diets, the AS model rats were provided a high-fat diet, two of the experimental groups fed with a high-fat diet were treated with Myrtenal (50 mg/kg and 100 mg/kg), and one experimental group on high-fat diet was treated with simvastatin (10 mg/kg) for 30 days. The levels of inflammatory cytokines were analyzed using kits. The lipoproteins and the lipid profile were estimated using an auto-analyzer. The atherogenic index and marker enzyme activities were also determined. Serum concentrations of 6-keto-prostaglandin F1α (6-keto-PGF1α), thromboxaneB2 (TXB2), endothelin (ET), and nitric oxide (NO) were measured. The AS model groups indicated altered lipid profile, lipoprotein content, atherogenic index, calcium levels, HMG-CoA reductase activity, collagen level, and mild mineralization indicating atherosclerosis, while the AS-induced Myrtenal-treated groups demonstrated anti-atherogenic activity. The Myrtenal-treated groups exhibited a decreased TC, TG, and LDLc levels; increased HDLc levels; and a decline in the inflammatory cytokines such as CRP, IL-1β, IL-8, and IL-18 when compared to the untreated AS rats. Furthermore, Myrtenal decreased ET, TXB2, and 6-keto-PGF1α levels indicating its anti-atherosclerotic activity. The study results thus indicate that Myrtenal modulates the lipid metabolic pathway to exert its anti-atherosclerotic activity.

Metabolomic Profiling of Angiotensin-II-Induced Abdominal Aortic Aneurysm in Ldlr-/- Mice Points to Alteration of Nitric Oxide, Lipid, and Energy Metabolisms

Aneurysm is the second-most common disease affecting the aorta worldwide after atherosclerosis. While several clinical metabolomic studies have been reported, no study has reported deep metabolomic phenotyping in experimental animal models of aortic aneurysm. We performed a targeted metabolomics study on the blood and aortas of an experimental mice model of aortic aneurysm generated by high-cholesterol diet and angiotensin II in Ldlr^−/− mice. The mice model showed a significant increase in media/lumen ratio and wall area, which is associated with lipid deposition within the adventitia, describing a hypertrophic remodeling with an aneurysm profile of the abdominal aorta. Altered aortas showed increased collagen remodeling, disruption of lipid metabolism, decreased glucose, nitric oxide and lysine metabolisms, and increased polyamines and asymmetric dimethylarginine (ADMA) production. In blood, a major hyperlipidemia was observed with decreased concentrations of glutamine, glycine, taurine, and carnitine, and increased concentrations of the branched amino acids (BCAA). The BCAA/glycine and BCAA/glutamine ratios discriminated with very good sensitivity and specificity between aneurysmatic and non-aneurysmatic mice. To conclude, our results reveal that experimental induction of aortic aneurysms causes a profound alteration in the metabolic profile in aortas and blood, mainly centered on an alteration of NO, lipid, and energetic metabolisms.

Multi-Omics Signatures Link to Ticagrelor Effects on Vascular Function in Patients With Acute Coronary Syndrome

BACKGROUND

Long-term antiplatelet agents including the potent P2Y12 antagonist ticagrelor are indicated in patients with a previous history of acute coronary syndrome. We sought to compare the effect of ticagrelor with that of aspirin monotherapy on vascular endothelial function in patients with prior acute coronary syndrome.

METHODS

This was a prospective, single center, parallel group, investigator-blinded randomized controlled trial. We randomized 200 patients on long-term aspirin monotherapy with prior acute coronary syndrome in a 1:1 fashion to receive ticagrelor 60 mg BD (n=100) or aspirin 100 mg OD (n=100). The primary end point was change from baseline in brachial artery flow-mediated dilation at 12 weeks. Secondary end points were changes to platelet activation marker (CD41_62p) and endothelial progenitor cell (CD34/133) count measured by flow cytometry, plasma level of adenosine, IL-6 (interleukin-6) and EGF (epidermal growth factor), and multi-omics profiling at 12 weeks.

RESULTS

After 12 weeks, brachial flow-mediated dilation was significantly increased in the ticagrelor group compared with the aspirin group (ticagrelor: 3.48±3.48% versus aspirin: -1.26±2.85%, treatment effect 4.73 [95% CI, 3.85-5.62], P<0.001). Nevertheless ticagrelor treatment for 12 weeks had no significant effect on platelet activation markers, circulating endothelial progenitor cell count or plasma level of adenosine, IL-6, and EGF (all P>0.05). Multi-omics pathway assessment revealed that changes in the metabolism and biosynthesis of amino acids (cysteine and methionine metabolism; phenylalanine, tyrosine, and tryptophan biosynthesis) and phospholipids (glycerophosphoethanolamines and glycerophosphoserines) were associated with improved brachial artery flow-mediated dilation in the ticagrelor group.

CONCLUSIONS

In patients with prior acute coronary syndrome, ticagrelor 60 mg BD monotherapy significantly improved brachial flow-mediated dilation compared with aspirin monotherapy and was associated with significant changes in metabolomic and lipidomic signatures.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03881943.