Genetic associations with carotid intima-media thickness link to atherosclerosis with sex-specific effects in sub-Saharan Africans

Cardiac Molecular Analysis Reveals Aging-Associated Metabolic Alterations Promoting Glycosaminoglycans Accumulation via Hexosamine Biosynthetic Pathway

Age is a prominent risk factor for cardiometabolic disease, often leading to heart structural and functional changes. However, precise molecular mechanisms underlying cardiac remodeling and dysfunction exclusively resulting from physiological aging remain elusive. Previous research demonstrated age-related functional alterations in baboons, analogous to humans. The goal of this study is to identify early cardiac molecular alterations preceding functional adaptations, shedding light on the regulation of age-associated changes. Unbiased transcriptomics of left ventricle samples are performed from female baboons aged 7.5-22.1 years (human equivalent ≈30-88 years). Weighted-gene correlation network and pathway enrichment analyses are performed, with histological validation. Modules of transcripts negatively correlated with age implicated declined metabolism-oxidative phosphorylation, tricarboxylic acid cycle, glycolysis, and fatty-acid β-oxidation. Transcripts positively correlated with age suggested a metabolic shift toward glucose-dependent anabolic pathways, including hexosamine biosynthetic pathway (HBP). This shift is associated with increased glycosaminoglycan synthesis, modification, precursor synthesis via HBP, and extracellular matrix accumulation, verified histologically. Upregulated extracellular matrix-induced signaling coincided with glycosaminoglycan accumulation, followed by cardiac hypertrophy-related pathways. Overall, these findings revealed a transcriptional shift in metabolism favoring glycosaminoglycan accumulation through HBP before cardiac hypertrophy. Unveiling this metabolic shift provides potential targets for age-related cardiac diseases, offering novel insights into early age-related mechanisms.

Targeting mitochondrial dynamics and redox regulation in cardiovascular diseases

Accumulating evidence highlights the pivotal role of mitochondria in cardiovascular diseases (CVDs). Understanding the molecular mechanisms underlying mitochondrial dysfunction is crucial for developing targeted therapeutics. Recent years have seen substantial advancements in unraveling mitochondrial regulatory pathways in both normal and pathological states and the development of potent drugs. However, specific delivery of drugs into the mitochondria is still a challenge. We present recent findings on regulators of mitochondrial dynamics and reactive oxygen species (ROS), critical factors influencing mitochondrial function in CVDs. We also discuss advancements in drug delivery strategies aimed at overcoming the technical barrier in targeting mitochondria for CVD treatment.

2024 Heart Disease and Stroke Statistics: A Report of US and Global Data From the American Heart Association

BACKGROUND

The American Heart Association (AHA), in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, nutrition, sleep, and obesity) and health factors (cholesterol, blood pressure, glucose control, and metabolic syndrome) that contribute to cardiovascular health. The AHA Heart Disease and Stroke Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, brain health, complications of pregnancy, kidney disease, congenital heart disease, rhythm disorders, sudden cardiac arrest, subclinical atherosclerosis, coronary heart disease, cardiomyopathy, heart failure, valvular disease, venous thromboembolism, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The AHA, through its Epidemiology and Prevention Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States and globally to provide the most current information available in the annual Statistical Update with review of published literature through the year before writing. The 2024 AHA Statistical Update is the product of a full year's worth of effort in 2023 by dedicated volunteer clinicians and scientists, committed government professionals, and AHA staff members. The AHA strives to further understand and help heal health problems inflicted by structural racism, a public health crisis that can significantly damage physical and mental health and perpetuate disparities in access to health care, education, income, housing, and several other factors vital to healthy lives. This year's edition includes additional global data, as well as data on the monitoring and benefits of cardiovascular health in the population, with an enhanced focus on health equity across several key domains.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

The impact of cumulative exposure to diverse lipid profiles on carotid intima-media thickness among an asymptomatic population

BACKGROUND AND AIMS

We aimed to investigate the relationship between the cumulative exposure to different lipid parameters and carotid intima-media thickness(CIMT), which is considered a marker for the early stage of atherosclerosis. This is due to the shift in research focus from assessing individual lipoproteins to considering their cumulative exposure.

METHODS AND RESULTS

The study included 2,348 participants who had their lipid parameters measured biennially since 2006.To calculate the cumulative lipid burden, the weighted sum of the difference between the measured value and the cutoff value of each parameter, including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDLC), high-density lipoprotein cholesterol (HDLC), and non-HDLC, was added. Carotid ultrasound was used to detect CIMT. The association between cumulative lipid burden and CIMT was evaluated using linear and logistic analyses. TC and LDLC burden were significantly associated with thickening CIMT (p<0.05). A 2.65-fold, 1.67-fold increased risk of abnormal CIMT was documented in the highest quartile of these two lipid burdens. Notably, a dose-dependent relationship was observed in the overall population when taking non-HDLC burden as a continuous variable (fully-adjusted β coefficient=0.0013, 95%CI 0.0004-0.0022).

CONCLUSIONS

Out of the five lipid parameters, TC and LDLC burden showed independent associations with abnormal CIMT. it is crucial to attain optimal lipid levels for the prevention and treatment of subclinical atherosclerosis.

Cardiac Molecular Analysis Reveals Aging-Associated Metabolic Alterations Promoting Glycosaminoglycans Accumulation Via Hexosamine Biosynthetic Pathway

Age is a prominent risk factor for cardiometabolic disease, and often leads to heart structural and functional changes. However, precise molecular mechanisms underlying cardiac remodeling and dysfunction resulting from physiological aging per se remain elusive. Understanding these mechanisms requires biological models with optimal translation to humans. Previous research demonstrated that baboons undergo age-related reduction in ejection fraction and increased heart sphericity, mirroring changes observed in humans. The goal of this study was to identify early cardiac molecular alterations that precede functional adaptations, shedding light on the regulation of age-associated changes. We performed unbiased transcriptomics of left ventricle (LV) samples from female baboons aged 7.5-22.1 years (human equivalent ~30-88 years). Weighted-gene correlation network and pathway enrichment analyses were performed to identify potential age-associated mechanisms in LV, with histological validation. Myocardial modules of transcripts negatively associated with age were primarily enriched for cardiac metabolism, including oxidative phosphorylation, tricarboxylic acid cycle, glycolysis, and fatty-acid β-oxidation. Transcripts positively correlated with age suggest upregulation of glucose uptake, pentose phosphate pathway, and hexosamine biosynthetic pathway (HBP), indicating a metabolic shift towards glucose-dependent anabolic pathways. Upregulation of HBP commonly results in increased glycosaminoglycan precursor synthesis. Transcripts involved in glycosaminoglycan synthesis, modification, and intermediate metabolism were also upregulated in older animals, while glycosaminoglycan degradation transcripts were downregulated with age. These alterations would promote glycosaminoglycan accumulation, which was verified histologically. Upregulation of extracellular matrix (ECM)-induced signaling pathways temporally coincided with glycosaminoglycan accumulation. We found a subsequent upregulation of cardiac hypertrophy-related pathways and an increase in cardiomyocyte width. Overall, our findings revealed a transcriptional shift in metabolism from catabolic to anabolic pathways that leads to ECM glycosaminoglycan accumulation through HBP prior to upregulation of transcripts of cardiac hypertrophy-related pathways. This study illuminates cellular mechanisms that precede development of cardiac hypertrophy, providing novel potential targets to remediate age-related cardiac diseases.

Sex differences in the genetic and molecular mechanisms of coronary artery disease

Sex differences in coronary artery disease (CAD) presentation, risk factors and prognosis have been widely studied. Similarly, studies on atherosclerosis have shown prominent sex differences in plaque biology. Our understanding of the underlying genetic and molecular mechanisms that drive these differences remains fragmented and largely understudied. Through reviewing genetic and epigenetic studies, we identified more than 40 sex-differential candidate genes (13 within known CAD loci) that may explain, at least in part, sex differences in vascular remodeling, lipid metabolism and endothelial dysfunction. Studies with transcriptomic and single-cell RNA sequencing data from atherosclerotic plaques highlight potential sex differences in smooth muscle cell and endothelial cell biology. Especially, phenotypic switching of smooth muscle cells seems to play a crucial role in female atherosclerosis. This matches the known sex differences in atherosclerotic phenotypes, with men being more prone to lipid-rich plaques, while women are more likely to develop fibrous plaques with endothelial dysfunction. To unravel the complex mechanisms that drive sex differences in CAD, increased statistical power and adjustments to study designs and analysis strategies are required. This entails increasing inclusion rates of women, performing well-defined sex-stratified analyses and the integration of multi-omics data.

Assessment of asprosin level and some of physiological variables in patients with cardiovascular diseases in Kirkuk city, Iraq

Introduction and Aim: Asprosin is a novel fasting-induced glucogenic adipokine, which stimulates the liver to release glucose into the blood stream. The aim of this study was to examine the role of asprosin as well as various physiological and oxidative stress factors in atherosclerosis and myocardial infarction patients in comparison to healthy controls in Kirkuk city, in order to clarify whether asprosin helps in protecting heart and preventing heart disease.   Materials and Methods: This study included blood samples collected from patients (n=70) and normal healthy controls (n=20), aged between 45-65 years from the Kirkuk General Hospital and external specialized clinical between December 2021 to February 2022. The samples were divided into three groups which included healthy controls (n=20), patients suffering from atherosclerosis (n=40) and myocardial infarction (n=30) respectively. Individuals in all groups were tested for their blood ASP, CPK-BM Tnt and lipid profile levels. Blood serum was also tested for concentration of FBS, INS, HbA1c, MDA and GSH.   Results: The asprosin, CPK-BM, Cardiac troponin (TNt) and INS levels was observed to be significantly elevated in atherosclerosis patients in comparison to healthy controls. However, in myocardial infarction patients significant increase levels was seen only for CPK-BM and INS levels. Lipid profiling showed that except for HDL levels, significant increased levels for TC, TG, LDL and VLDL in both atherosclerosis and MI patients as compared to healthy individuals. The concentration of FBS was seen elevated in blood serum of atherosclerosis and MI patients in comparison to controls.  No significant increase was observed for HbA1c and oxidative stress hormones MDA and GSH).   Conclusion: Changes in asprosin levels in patients with cardiovascular disease could be considered as a biochemical marker to estimate the severity of injury in heart and heart muscles.