Modified Lipoproteins Induce Arterial Wall Inflammation During Atherogenesis

Apolipoprotein B-containing lipoproteins in atherogenesis

Apolipoprotein B (apoB) is the main structural protein of LDLs, triglyceride-rich lipoproteins and lipoprotein(a), and is crucial for their formation, metabolism and atherogenic properties. In this Review, we present insights into the role of apoB-containing lipoproteins in atherogenesis, with an emphasis on the mechanisms leading to plaque initiation and growth. LDL, the most abundant cholesterol-rich lipoprotein in plasma, is causally linked to atherosclerosis. LDL enters the artery wall by transcytosis and, in vulnerable regions, is retained in the subendothelial space by binding to proteoglycans via specific sites on apoB. A maladaptive response ensues. This response involves modification of LDL particles, which promotes LDL retention and the release of bioactive lipid products that trigger inflammatory responses in vascular cells, as well as adaptive immune responses. Resident and recruited macrophages take up modified LDL, leading to foam cell formation and ultimately cell death due to inadequate cellular lipid handling. Accumulation of dead cells and cholesterol crystallization are hallmarks of the necrotic core of atherosclerotic plaques. Other apoB-containing lipoproteins, although less abundant, have substantially greater atherogenicity per particle than LDL. These lipoproteins probably contribute to atherogenesis in a similar way to LDL but might also induce additional pathogenic mechanisms. Several targets for intervention to reduce the rate of atherosclerotic lesion initiation and progression have now been identified, including lowering plasma lipoprotein levels and modulating the maladaptive responses in the artery wall.

Research of the clinical features, risk factors, and surgical diagnosis of intramural stones in patients with gallbladder stones

Crystals or stones within the gallbladder wall in patients with gallbladder stones (GBS) have been occasionally reported, but their clinical features and aetiology remain unclear. This retrospective study analysed 323 consecutive patients with GBS who underwent rigid choledochoscopic gallbladder-preserving cholecystolithotomy to determine the detection rate, clinical features, and potential risk factors of gallbladder intramural stones (IS). IS were found in 24.1% (78/323) of patients, characterised by distinct cholangioscopic findings, including stone shadows, yellow floating bands, or a combination of both within the gallbladder wall. Compared to patients without IS, those with IS had a higher prevalence of Clonorchis sinensis (C. sinensis) eggs (60.3% vs. 40.8%, P < 0.05) and elevated serum cholesterol, LDL cholesterol, and Apo-B levels (P < 0.05). However, stone composition and C. sinensis egg detection rates did not differ between intraluminal stones and IS within the same patient (P > 0.05). Logistic regression analysis revealed that IS were associated with C. sinensis infection and elevated Apo-B levels. In conclusion, IS share homology with intraluminal stones in the same patient with GBS and exhibit unique appearances in rigid choledochoscopy. For patients with GBS and IS, elevated serum Apo-B levels and C. sinensis infection were independent risk factors.

Gram-negative bacteria activate cellular pathways in plaque microenvironment; Systems biology approach

BACKGROUND

Inflammatory events followed by bacterial infections are related to the progression of the atherosclerosis process. The study investigated the signaling and metabolic pathways of endothelial cells (ECs), macrophages (MQs), vascular smooth muscle cells (VSMCs), and dendritic cells (DCs) after exposure to Gram-negative bacterial infections. Moreover, it aimed at cross-talking and enriching the pathways on the cellular and plaque networks.

METHODS AND MATERIALS

High-throughput expression data series (n = 9) were selected through GEO and MAT data repositories. Upregulated differential expression genes (DEGs) were determined using R software and applied to identify the cellular signaling pathways using Enricher/Reactome tools. Then, the cell networks were visualized using the Cytoscape software and enriched by the pathways of secretory proteins identified using Gene ontology (GO).

RESULTS

The important pathways of the Cytokines (Degree 4, p < 6 × 10-26), and INF (Degree 4, p < 8.6 × 10-31) in ECs, Cytokines (Degree 4, p < 9.35 × 10-8), and GPCR (Degree 3, p < 1.45 × 10-4) in MQs, NOTCH (Degree 6, p < 0.027) in VSMCs, and Cytokines (Degree 4, p < 1.45 × 10-17) in DCs were found to be activated and enriched after exposure to Gram-negative bacterial infections on the cell networks. Furthermore, the Netrin- 1 (Degree 6, p < 0.028), and EGFR (Degree 5, p < 0.036) pathways were activated in the intimal thick/xanthoma plaque network while the innate (Degree 9, p < 8.9 × 10-20) and adaptive (Degree 7, p < 4.1 × 10-12) immune systems pathways were activated in the fibrous cap atheroma plaque network.

CONCLUSION

The study revealed the signaling pathways after exposure to Gram-negative bacterial infections on the cell networks in the vessel microenvironment. Furthermore, the cell cross-talks exacerbated these pathways in cells and unstable plaques.

CLINICAL TRIAL NUMBER

Not applicable.

Melatonin as a treatment for atherosclerosis: focus on programmed cell death, inflammation and oxidative stress

Delaying the development of atherosclerosis (AS) and decreasing cardiac ischemia-reperfusion damage remain serious challenges for the medical community. Chronic arterial disease, i.e., AS, is frequently linked to oxidative stress and inflammation as significant contributing causes. AS risk factors, such as hyperlipidemia, high blood pressure, age, hyperglycemia, smoking, high cholesterol, and irregular sleep patterns, can exacerbate AS in the carotid artery and further shrink its lumen. Finding new approaches that support plaque inhibition or stability is an ongoing problem. The last ten years have shown us that melatonin (MLT) affects the cardiovascular system, although its exact mechanisms of action are yet unknown. MLT's direct free radical scavenger activity, its indirect antioxidant qualities, and its anti-inflammatory capabilities all contribute to its atheroprotective effects on several pathogenic signaling pathways. Herein, we examine the evidence showing that MLT treatment has significant protective effects against AS and AS-related cardiovascular diseases. The numerous pieces of the puzzle that have been as for epigenetic and biogenetic targets for prevention and therapy against the atherosclerotic pathogenic processes are identified.

How Does HDL Participate in Atherogenesis? Antioxidant Activity Versus Role in Reverse Cholesterol Transport

Low-density lipoprotein (LDL) chemically modified by reactive oxygen species (ROS), for example, leaking from red blood cells in the vascular compartment, more readily crosses the vascular endothelium than does nonoxidatively modified LDL to enter tissue fluid. Oxidatively modified LDL (oxLDL) may also be created in the tissue fluid by ROS leaking from cells by design, for example, by inflammatory white cells, or simply leaking from other cells as a consequence of oxygen metabolism. As well as oxLDL, glycatively modified LDL (glycLDL) is formed in the circulation. High-density lipoprotein (HDL) appears capable of decreasing the burden of lipid peroxides formed on LDL exposed to ROS or to glucose and its metabolites. The mechanism for this that has received the most attention is the antioxidant activity of HDL, which is due in large part to the presence of paraoxonase 1 (PON1). PON1 is intimately associated with its apolipoprotein A1 component and with HDL's lipid domains into which lipid peroxides from LDL or cell membranes can be transferred. It is frequently overlooked that for PON1 to hydrolyze lipid substrates, it is essential that it remain by virtue of its hydrophobic amino acid sequences within a lipid micellar environment, for example, during its isolation from serum or genetically modified cells in tissue culture. Otherwise, it may retain its capacity to hydrolyze water-soluble substrates, such as phenyl acetate, whilst failing to hydrolyze more lipid-soluble molecules. OxLDL and probably glycLDL, once they have crossed the arterial endothelium by receptor-mediated transcytosis, are rapidly taken up by monocytes in a process that also involves scavenger receptors, leading to subendothelial foam cell formation. These are the precursors of atheroma, inducing more monocytes to cross the endothelium into the lesion and the proliferation and migration of myocytes present in the arterial wall into the developing lesion, where they transform into foam cells and fibroblasts. The atheroma progresses to have a central extracellular lake of cholesteryl ester following necrosis and apoptosis of foam cells with an overlying fibrous cap whilst continuing to grow concentrically around the arterial wall by a process involving oxLDL and glycLDL. Within the arterial wall, additional oxLDL is generated by ROS secreted by inflammatory cells and leakage from cells generally when couplet oxygen is reduced. PON1 is important for the mechanism by which HDL opposes atherogenesis, which may provide a better avenue of inquiry in the identification of vulnerable individuals and the provision of new therapies than have emerged from the emphasis placed on its role in RCT.

Short-Term Supplementation with 100% Bilberry Products and Its Effects on Body Composition and Lipid Profile in Overweight/Obese Women

Introduction: Overweight and obesity are major public health concerns, often leading to increased cardiovascular risk. Methods: This eight-week interventional study examined whether regular consumption of two natural bilberry products could improve body composition and lipid profiles in overweight/obese women. A total of 30 participants (aged 50-60 years) were assigned to consume either 125 mL/day of 100% bilberry juice or 10 g/day of 100% bilberry fibre, while maintaining their habitual diets and lifestyles. Results: Although no significant changes were found in anthropometric parameters or blood pressure in either group, both interventions reduced low-density lipoprotein cholesterol (LDL-C) and increased high-density lipoprotein cholesterol (HDL-C). Surprisingly, total cholesterol (TC) levels rose in the bilberry juice group (from 6.41 ± 1.23 mmol/L to 6.94 ± 1.30 mmol/L (p < 0.001)), and in the fibre group (from 6.06 ± 1.39 mmol/L to 6.43 ± 1.05 mmol/L (p = 0.046)), likely due to elevated HDL-C (p < 0.001) overshadowing the drop in LDL-C (p < 0.05). Triglyceride (TG) levels did not change significantly and were still within the reference range. Conclusions: Notably, the bilberry juice group experienced a significant reduction in atherogenic small dense LDL (sdLDL) subfractions, suggesting a favourable shift in cardiovascular risk factors. These findings highlight the potential of bilberry-based products as a supportive strategy for improving lipid profiles in overweight/obese women.

Oxidised low-density lipoprotein and adverse outcome in patients with acute mild ischaemic stroke or high-risk TIA: a secondary analysis of the INSPIRES randomised clinical trial

BACKGROUND

Research data regarding the correlation between elevated oxidised low-density lipoprotein (oxLDL) cholesterol concentrations and unfavourable clinical outcomes in individuals experiencing minor acute ischaemic cerebrovascular events or transient ischaemic attack (TIA) with presumed atherosclerotic aetiology are still limited.

METHODS

This investigation incorporated a cohort of 5814 participants derived from the Intensive Statin and Antiplatelet Therapy for Acute High-Risk Intracranial or Extracranial Atherosclerosis clinical trial. The core laboratory conducted blinded measurements of baseline plasma oxLDL concentrations. Multivariable Cox regression analyses were employed to assess the correlations between oxLDL levels and adverse clinical events. The principal endpoint for efficacy assessment was defined as the occurrence of stroke within a 90-day follow-up period. Additional secondary endpoints encompassed composite vascular events during the same observation window. The main safety endpoint assessed was the occurrence of bleeding events of moderate to severe intensity.

RESULTS

The final analytical cohort comprised 5814 patients included in the final analysis. The mean age was 63.7±9.6 years, and 36.0% were female. The average concentration of circulating oxLDL was 36.62 µg/dL. Elevated oxLDL concentrations demonstrated a potential correlation with heightened stroke risk (T3 vs T1: HR 1.39, 95% CI 1.04 to 1.85), ischaemic stroke (T3 vs T1: HR 1.31, 95% CI 0.98 to 1.76) and composite vascular events (T3 vs T1: HR 1.36, 95% CI 1.02 to 1.81) within 90 days. An increased concentration of oxLDL demonstrated a significant association with elevated susceptibility to moderate and severe haemorrhagic events (T3 vs T1: HR 3.61, 95% CI 1.26 to 10.34) within 90 days.

CONCLUSION

Increased concentrations of oxLDL demonstrated an independent correlation with both stroke recurrence and the occurrence of moderate-to-severe haemorrhagic events in individuals presenting with acute minor ischaemic stroke or TIA at elevated risk, accompanied by intracranial or extracranial atherosclerotic lesions.

Therapeutic and pharmacological applications of extracellular vesicles and lipoproteins

In recent years, various approaches have been undertaken to eliminate lipoproteins co-isolated with extracellular vesicles, as they were initially regarded as contaminating entities. However, novel discoveries are reshaping our perspective. In body fluids, these distinct particles not only co-exist, but also interactions between them are likely to occur. Extracellular vesicles and lipoproteins can associate with each other, share cargo, influence each other's functions, and jointly have a role in the pathomechanisms of diseases. Additionally, their association carries important implications for therapeutic and pharmacological aspects of lipid-lowering strategies. Extracellular vesicles and lipoprotein particles may have roles in the elimination of each other from the circulation. The objective of this minireview is to delve into these aspects. Here, we show that under certain physiological and pathological conditions, extracellular vesicles and lipoproteins are 'partners' rather than 'strangers' or 'rivals'.

Oxidized Low-Density Lipoprotein and Its Role in Immunometabolism

Modified cholesterols such as oxidized low-density lipoprotein (OxLDL) contribute to atherosclerosis and other disorders through the promotion of foam cell formation and inflammation. In recent years, it has become evident that immune cell responses to inflammatory molecules such as OxLDLs depend on cellular metabolic functions. This review examines the known effects of OxLDL on immunometabolism and immune cell responses in atherosclerosis and several other diseases. We additionally provide context on the relationship between OxLDL and aging/senescence and identify gaps in the literature and our current understanding in these areas.

Cucurbita Pepo L. Seed Oil Modulates Dyslipidemia and Neuronal Dysfunction in Tramadol-Induced Toxicity in Wistar Albino Rats

Objective: The modulating effects of Cucurbita pepo seed oil (CPSO) on dyslipidemia and neuronal dysfunction in tramadol toxicity were studied. Methods: Fifty-six albino rats were divided into seven groups of eight rats each after a 2-week acclimatization period. All animals had unrestricted access to water and feed, and treatments were administered orally once daily for 42 days. Glutamate dehydrogenase and glutaminase activities were assessed using brain homogenate, while lipid profiles were analyzed in serum samples. Results: Tramadol toxicity was evidenced by significant (P < 0.05) increases in brain glutamate dehydrogenase along with significant (P < 0.05) decreases in the activities of glutaminase in the group administered only tramadol. Also, serum levels of total cholesterol, LDL-C and triglycerides also increased significantly (P < 0.05) following administration of tramadol with decreased level of HDL-C (P < 0.05). However, treatment with CPSO significantly restored the activities and levels of the altered biochemical parameters in a dose-dependent manner. The results of the biochemical investigation using the lipid profile and the enzymes of glutamate metabolism were corroborated by the results obtained from the histopathological examination of the brain. Conclusion: The results of this study therefore suggest that tramadol-induced dyslipidemia and neuronal dysfunction be managed and prevented by the administration of Cucurbita pepo seed oil.

Stress granules in atherosclerosis: Insights and therapeutic opportunities

Atherosclerosis, a complex inflammatory and metabolic disorder, is the underlying cause of several life-threatening cardiovascular diseases. Stress granules (SG) are biomolecular condensates composed of proteins and mRNA that form in response to stress. Recent studies suggest a potential link between SG and atherosclerosis development. However, there remain gaps in understanding SG role in atherosclerosis development. Here we provide a thorough analysis of the role of SG in atherosclerosis, covering cellular stresses stimulation, core components, and regulatory genes in SG formation. Furthermore, we explore atherosclerosis induced factors such as inflammation, low or oscillatory shear stress (OSS), and oxidative stress (OS) may impact SG formation and then the development of atherosclerotic lesions. We have assessed how changes in SG dynamics impact pro-atherogenic processes like endothelial dysfunction, lipid metabolism, and immune cell recruitment in atherosclerosis. In summary, this review emphasizes the complex interplay between SG and atherosclerosis that could open innovative directions for targeted therapeutic strategies in preventing or treating atherosclerotic cardiovascular diseases.

Modulatory Impact of Oxidative Stress on Action Potentials in Pathophysiological States: A Comprehensive Review

Oxidative stress, characterized by an imbalance between the production of reactive oxygen species (ROS) and the body's antioxidant defenses, significantly affects cellular function and viability. It plays a pivotal role in modulating membrane potentials, particularly action potentials (APs), essential for properly functioning excitable cells such as neurons, smooth muscles, pancreatic beta cells, and myocytes. The interaction between oxidative stress and AP dynamics is crucial for understanding the pathophysiology of various conditions, including neurodegenerative diseases, cardiac arrhythmias, and ischemia-reperfusion injuries. This review explores how oxidative stress influences APs, focusing on alterations in ion channel biophysics, gap junction, calcium dynamics, mitochondria, and Interstitial Cells of Cajal functions. By integrating current research, we aim to elucidate how oxidative stress contributes to disease progression and discuss potential therapeutic interventions targeting this interaction.

Novel Role of Endothelial CD45 in Regulating Endothelial-to-Mesenchymal Transition in Atherosclerosis

Background

Protein-tyrosine-phosphatase CD45 is exclusively expressed in all nucleated cells of the hematopoietic system but is rarely expressed in endothelial cells. Interestingly, our recent study indicated that activation of the endogenous CD45 promoter in human endothelial colony forming cells (ECFCs) induced expression of multiple EndoMT marker genes. However, the detailed molecular mechanisms underlying CD45 that drive EndoMT and the therapeutic potential of manipulation of CD45 expression in atherosclerosis are entirely unknown.

Method

We generated a tamoxifen-inducible EC-specific CD45 deficient mouse strain (EC-iCD45KO) in an ApoE-deficient (ApoE-/-) background and fed with a Western diet (C57BL/6) for atherosclerosis and molecular analyses. We isolated and enriched mouse aortic endothelial cells with CD31 beads to perform single-cell RNA sequencing. Biomedical, cellular, and molecular approaches were utilized to investigate the role of endothelial CD45-specific deletion in the prevention of EndoMT in ApoE-/- model of atherosclerosis.

Results

Single-cell RNA sequencing revealed that loss of endothelial CD45 inhibits EndoMT marker expression and transforming growth factor-β signaling in atherosclerotic mice. which is associated with the reductions of lesions in the ApoE-/- mouse model. Mechanistically, the loss of endothelial cell CD45 results in increased KLF2 expression, which inhibits transforming growth factor-β signaling and EndoMT. Consistently, endothelial CD45 deficient mice showed reduced lesion development, plaque macrophages, and expression of cell adhesion molecules when compared to ApoE-/- controls.

Conclusions

These findings demonstrate that the loss of endothelial CD45 protects against EndoMT-driven atherosclerosis, promoting KLF2 expression while inhibiting TGFβ signaling and EndoMT markers. Thus, targeting endothelial CD45 may be a novel therapeutic strategy for EndoMT and atherosclerosis.

Emerging role of sphingolipids and extracellular vesicles in development and therapeutics of cardiovascular diseases

Sphingolipids are eighteen carbon alcohol lipids synthesized from non-sphingolipid precursors in the endoplasmic reticulum (ER). The sphingolipids serve as precursors for a vast range of moieties found in our cells that play a critical role in various cellular processes, including cell division, senescence, migration, differentiation, apoptosis, pyroptosis, autophagy, nutrition intake, metabolism, and protein synthesis. In CVDs, different subclasses of sphingolipids and other derived molecules such as sphingomyelin (SM), ceramides (CERs), and sphingosine-1-phosphate (S1P) are directly related to diabetic cardiomyopathy, dilated cardiomyopathy, myocarditis, ischemic heart disease (IHD), hypertension, and atherogenesis. Several genome-wide association studies showed an association between genetic variations in sphingolipid pathway genes and the risk of CVDs. The sphingolipid pathway plays an important role in the biogenesis and secretion of exosomes. Small extracellular vesicles (sEVs)/ exosomes have recently been found as possible indicators for the onset of CVDs, linking various cellular signaling pathways that contribute to the disease progression. Important features of EVs like biocompatibility, and crossing of biological barriers can improve the pharmacokinetics of drugs and will be exploited to develop next-generation drug delivery systems. In this review, we have comprehensively discussed the role of sphingolipids, and sphingolipid metabolites in the development of CVDs. In addition, concise deliberations were laid to discuss the role of sEVs/exosomes in regulating the pathophysiological processes of CVDs and the exosomes as therapeutic targets.

Photodynamic Therapy for Atherosclerosis: Past, Present, and Future

This review paper examines the evolution of photodynamic therapy (PDT) as a novel, minimally invasive strategy for treating atherosclerosis, a leading global health concern. Atherosclerosis is characterized by the accumulation of lipids and inflammation within arterial walls, leading to significant morbidity and mortality through cardiovascular diseases such as myocardial infarction and stroke. Traditional therapeutic approaches have primarily focused on modulating risk factors such as hypertension and hyperlipidemia, with emerging evidence highlighting the pivotal role of inflammation. PDT, leveraging a photosensitizer, specific-wavelength light, and oxygen, offers targeted treatment by inducing cell death in diseased tissues while sparing healthy ones. This specificity, combined with advancements in nanoparticle technology for improved delivery, positions PDT as a promising alternative to traditional interventions. The review explores the mechanistic basis of PDT, its efficacy in preclinical studies, and the potential for enhancing plaque stability and reducing macrophage density within plaques. It also addresses the need for further research to optimize treatment parameters, mitigate adverse effects, and validate long-term outcomes. By detailing past developments, current progress, and future directions, this paper aims to highlight PDT's potential in revolutionizing atherosclerosis treatment, bridging the gap from experimental research to clinical application.

The Prevalence of Risk Factors for Cardiovascular Diseases in Najran Region, Saudi Arabia

The primary goal of this study was to investigate the knowledge, prevalence, and risk factors of cardiovascular diseases among individuals in the Najran region of Saudi Arabia. In the Najran region of Saudi Arabia, an online cross-sectional survey was conducted. Between September and October 2023, a self-administered questionnaire was distributed to a random sample of the general population aged 18 and up. The survey instrument asked about history and exposure, physician-diagnosed illnesses, cardiovascular diseases (CVDs), medication use, and other risk factors. This research had a total of 2046 individuals. Around one-fifth of the study participants reported that they or a family member suffered from CVD, and arrhythmia was the most commonly reported; blood tests, cardiac catheterization, and ECG were the most commonly reported tests performed for CVD patients, around one-tenth of CVD patients reported that they do not have any chronic diseases other than CVD, and the vast majority of the patients confirmed their regular medical appointments. This is one of the first studies to investigate the knowledge, prevalence, and use of CVD drugs among individuals in the Najran region of Saudi Arabia. The study participants' lack of knowledge about CVD could lead to ineffective preventive measures and poor patient outcomes. The study's findings underscore the crucial need for more extensive and efficient educational initiatives that consider the targeted population's talents, attitudes, and perceptions.

RFX1 regulates foam cell formation and atherosclerosis by mediating CD36 expression

BACKGROUND AND AIMS

Atherosclerosis (AS) is a continuously low-grade inflammatory disease, and monocyte-derived macrophages play a vital role in AS pathogenesis. Regulatory factor X1 (RFX1) has been reported to participate in differentiation of various cells. Our previous report showed that RFX1 expression in CD14+ monocytes from AS patients was decreased and closely related to AS development. Macrophages mostly derive from monocytes and play an important role in AS plaque formation and stability. However, the functions of RFX1 in the formation of macrophage-derived foam cells and consequent AS development are unclear.

METHODS

We explored the effects of RFX1 on oxidation low lipoprotein (ox-LDL)-stimulated foam cell formation and CD36 expression by increasing or silencing Rfx1 expression in mouse peritoneal macrophages (PMAs). The ApoE-/-Rfx1f/f or ApoE-/-Rfx1f/f Lyz2-Cre mice fed a high-fat diet for 24 weeks were used to further examine the effect of RFX1 on AS pathogenesis. We then performed dual luciferase reporter assays to study the regulation of RFX1 for CD36 transcription.

RESULTS

Our results demonstrate that RFX1 expression was significantly reduced in ox-LDL induced foam cells and negatively correlated with lipid uptake in macrophages. Besides, Rfx1 deficiency in myeloid cells aggravated atherosclerotic lesions in ApoE-/- mice. Mechanistically, RFX1 inhibited CD36 expression by directly regulating CD36 transcription in macrophages.

CONCLUSIONS

The reduction of RFX1 expression in macrophages is a vital determinant for foam cell formation and the initiation of AS, proving a potential novel approach for the treatment of AS disease.

Non-oxidative Modified Low-density Lipoproteins: The Underappreciated Risk Factors for Atherosclerosis

Atherosclerosis, the pathological basis of most cardiovascular diseases, is a main risk factor causing about 20 million deaths each year worldwide. Oxidized low-density lipoprotein is recognized as the most important and independent risk factor in initiating and promoting atherosclerosis. Numerous antioxidants are extensively used in clinical practice, but they have no significant effect on reducing the morbidity and mortality of cardiovascular diseases. This finding suggests that researchers should pay more attention to the important role of non-oxidative modified low-density lipoprotein in atherosclerosis with a focus on oxidized low-density lipoprotein. This review briefly summarizes several important non-oxidative modified low-density lipoproteins associated with atherosclerosis, introduces the pathways through which these non-oxidative modified low-density lipoproteins induce the development of atherosclerosis in vivo, and discusses the mechanism of atherogenesis induced by these non-oxidative modified low-density lipoproteins. New therapeutic strategies and potential drug targets are provided for the prevention and treatment of atherosclerotic cardiovascular diseases.

Anatomical Distribution Patterns of Peripheral Arterial Disease in the Upper Extremities According to Patient Characteristics: A Retrospective Cohort Study

Purpose

Peripheral arterial disease (PAD) greatly affects the patients' quality of life. We aimed to investigate the affected anatomical sites and distribution patterns in upper extremity PAD using computed tomography angiography (CTA). Furthermore, we sought to identify the correlations between patient characteristics and the identified patterns.

Patients and Methods

This was a retrospective chart review of upper limb CTA findings from patients with symptomatic PAD aged >18 years. Significant variables from univariate logistic regression analysis were further tested using multivariate logistic regression analysis. Statistical significance was set at p < 0.05, with confidence intervals of 95%.

Results

The mean age of the 102 included patients with upper extremity PAD was 55.45 years. Laterality analysis revealed that the upper left limb segments were more affected than the upper right limb segments (42 vs 63; left-to-right ratio, 3:2). The forearm was the segment most affected by stenotic PAD (62 segments, 3.37%). The arm was the segment most affected by occlusive PAD (14 segments, 0.76%). Diabetes mellitus (DM) and hypertension (HTN) were significant predictors of PAD (p = 0.046). In patients with DM, the occlusive form of PAD was dominant in the arm (18.18%); however, the stenotic form prevailed in the forearm (72.72%). In patients with HTN, the occlusive form of PAD was predominant in the arm (45.45%); however, the stenotic form tended to occur in the arm and forearm (90.90%).

Conclusion

The distribution patterns of upper extremity PAD are linked to its underlying pathophysiology. HTN and DM are the most frequent comorbidities in patients with upper extremity PAD. Angiographically, PAD in these patients is likely to present as stenosis rather than as occlusion. This is vital for interventionists who deviate from radial arterial access in patients with PAD. Therefore, targeted screening standards are required, and further studies on PAD are warranted.

Imipramine Treatment Alters Sphingomyelin, Cholesterol, and Glycerophospholipid Metabolism in Isolated Macrophage Lysosomes

Lysosomes are degradative organelles that facilitate the removal and recycling of potentially cytotoxic materials and mediate a variety of other cellular processes, such as nutrient sensing, intracellular signaling, and lipid metabolism. Due to these central roles, lysosome dysfunction can lead to deleterious outcomes, including the accumulation of cytotoxic material, inflammation, and cell death. We previously reported that cationic amphiphilic drugs, such as imipramine, alter pH and lipid metabolism within macrophage lysosomes. Therefore, the ability for imipramine to induce changes to the lipid content of isolated macrophage lysosomes was investigated, focusing on sphingomyelin, cholesterol, and glycerophospholipid metabolism as these lipid classes have important roles in inflammation and disease. The lysosomes were isolated from control and imipramine-treated macrophages using density gradient ultracentrifugation, and mass spectrometry was used to measure the changes in their lipid composition. An unsupervised hierarchical cluster analysis revealed a clear differentiation between the imipramine-treated and control lysosomes. There was a significant overall increase in the abundance of specific lipids mostly composed of cholesterol esters, sphingomyelins, and phosphatidylcholines, while lysophosphatidylcholines and ceramides were overall decreased. These results support the conclusion that imipramine's ability to change the lysosomal pH inhibits multiple pH-sensitive enzymes in macrophage lysosomes.

When nitrosative stress hits the endoplasmic reticulum: Possible implications in oxLDL/oxysterols-induced endothelial dysfunction

Oxidized LDL (oxLDL) and oxysterols are known to play a crucial role in endothelial dysfunction (ED) by inducing endoplasmic reticulum stress (ERS), inflammation, and apoptosis. However, the precise molecular mechanisms underlying these pathophysiological processes remain incompletely understood. Emerging evidence strongly implicates excessive nitric oxide (NO) production in the progression of various pathological conditions. The accumulation of reactive nitrogen species (RNS) leading to nitrosative stress (NSS) and aberrant protein S-nitrosylation contribute to NO toxicity. Studies have highlighted the involvement of NSS and S-nitrosylation in perturbing ER signaling through the modification of ER sensors and resident isomerases in neurons. This review focuses on the existing evidence that strongly associates NO with ERS and the possible implications in the context of ED induced by oxLDL and oxysterols. The potential effects of perturbed NO synthesis on signaling effectors linking NSS with ERS in endothelial cells are discussed to provide a conceptual framework for further investigations and the development of novel therapeutic strategies targeting ED.

Atherosclerosis and Its Related Laboratory Biomarkers

Atherosclerosis constitutes a persistent inflammatory ailment, serving as the predominant underlying condition for coronary artery disease (CAD), peripheral artery disease (PAD), and cerebrovascular disease. The progressive buildup of plaques within the walls of medium- and large-caliber arteries characterizes the atherosclerotic process. This accumulation results in significant narrowing that impedes blood flow, leading to critical tissue oxygen deficiency. Spontaneous blockage of thrombotic vessels can precipitate stroke and myocardial infarction, which are complications representing the primary global causes of mortality. Present-day models for predicting cardiovascular risk incorporate conventional risk factors to gauge the likelihood of cardiovascular events over a ten-year span. In recent times, researchers have identified serum biomarkers associated with an elevated risk of atherosclerotic events. Many of these biomarkers, whether used individually or in combination, have been integrated into risk prediction models to assess whether their inclusion enhances predictive accuracy. In this review, we have conducted a comprehensive analysis of the most recently published literature concerning serum biomarkers associated with atherosclerosis. We have explored the potential utility of incorporating these markers in guiding clinical decisions.

Might Gut Microbiota Be a Target for a Personalized Therapeutic Approach in Patients Affected by Atherosclerosis Disease?

In recent years, the increasing number of studies on the relationship between the gut microbiota and atherosclerosis have led to significant interest in this subject. The gut microbiota, its metabolites (metabolome), such as TMAO, and gut dysbiosis play an important role in the development of atherosclerosis. Furthermore, inflammation, originating from the intestinal tract, adds yet another mechanism by which the human ecosystem is disrupted, resulting in the manifestation of metabolic diseases and, by extension, cardiovascular diseases. The scientific community must understand and elucidate these mechanisms in depth, to gain a better understanding of the relationship between atherosclerosis and the gut microbiome and to promote the development of new therapeutic targets in the coming years. This review aims to present the knowledge acquired so far, to trigger others to further investigate this intriguing topic.

Use of Apolipoprotein B in the Era of Precision Medicine: Time for a Paradigm Change?

Atherosclerotic cardiovascular disease (ASCVD) remains the leading cause of death worldwide and the risk of a major cardiovascular event is highest among those with established disease. Ongoing management of these patients relies on the accurate assessment of their response to any prescribed therapy, and their residual risk, in order to optimize treatment. Recent international guidelines and position statements concur that the plasma concentration of apolipoprotein B (apoB) is the most accurate measure of lipoprotein associated ASCVD risk. This is especially true for the growing number of individuals with diabetes, obesity, or the metabolic syndrome, and those on statin therapy. Most guidelines, however, continue to promote LDL-C as the primary risk marker due to uncertainty as to whether the greater accuracy of apoB is sufficient to warrant a paradigm shift. Recommendations regarding apoB measurement vary, and the information provided on how to interpret apoB results is sometimes insufficient, particularly for non-lipid specialists. Misinformation regarding the reliability of the assays is also frequently repeated despite its equivalent or better standardization than many other diagnostic assays. Thus, demand for apoB testing is relatively low, which means there is little incentive to increase its availability or reduce its cost. In this review, we examine the results of recent clinical outcomes studies and meta-analyses on the relative values of apoB, LDL-C, and non-HDL-C as markers of ASCVD risk. Although there is seemingly minimal difference among these markers when only population-based metrics are considered, it is evident from our analysis that, from a personalized or precision medicine standpoint, many individuals would benefit, at a negligible total cost, if apoB measurement were better integrated into the diagnosis and treatment of ASCVD.

Sex Differences Define the Vulnerability to Atherosclerosis

For several decades, atherosclerosis has attracted the attention of researchers around the world. Even being a major cause of serious cardiovascular disease and events, atherosclerosis is still not fully understood. Despite the fact that the main players in the pathogenesis of atherosclerosis are well known, many mechanisms of their implementation and interactions remain unknown. The same can be said about the risk factors for atherosclerosis. Many of them are known, but exactly how they work remains to be seen. The main objective of this review is to summarize the latest data on sex as a biological variable in atherosclerosis in humans and animals; to determine what we do not still know about how sex affects the process of growth and complications of atherosclerosis. In this review, we summarized data on sex differences at 3 atherosclerotic aspects: inflammation, vascular remodeling, and plaque morphology. With all overviewed data, we came to the conclusion on the atheroprotective role of female sex.

Immune Cell Infiltration Analysis Based on Bioinformatics Reveals Novel Biomarkers of Coronary Artery Disease

Background

Coronary artery disease (CAD) is a multifactorial immune disease, but research into the specific immune mechanism is still needed. The present study aimed to identify novel immune-related markers of CAD.

Methods

Three CAD-related datasets (GSE12288, GSE98583, GSE113079) were downloaded from the Gene Expression Integrated Database. Gene ontology annotation, Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis and weighted gene co-expression network analysis were performed on the common significantly differentially expressed genes (DEGs) of these three data sets, and the most relevant module genes for CAD obtained. The immune cell infiltration of module genes was evaluated with the CIBERSORT algorithm, and characteristic genes accompanied by their diagnostic effectiveness were screened by the machine-learning algorithm least absolute shrinkage and selection operator (LASSO) regression analysis. The expression levels of characteristic genes were evaluated in the peripheral blood mononuclear cells of CAD patients and healthy controls for verification.

Results

A total of 204 upregulated and 339 downregulated DEGs were identified, which were mainly enriched in the following pathways: "Apoptosis", "Th17 cell differentiation", "Th1 and Th2 cell differentiation", "Glycerolipid metabolism", and "Fat digestion and absorption". Five characteristic genes, LMAN1L, DOK4, CHFR, CEL and CCDC28A, were identified by LASSO analysis, and the results of the immune cell infiltration analysis indicated that the proportion of immune infiltrating cells (activated CD8 T cells and CD56 DIM natural killer cells) in the CAD group was lower than that in the control group. The expressions of CHFR, CEL and CCDC28A in the peripheral blood of the healthy controls and CAD patients were significantly different.

Conclusion

We identified CHFR, CEL and CCDC28A as potential biomarkers related to immune infiltration in CAD based on public data sets and clinical samples. This finding will contribute to providing a potential target for early noninvasive diagnosis and immunotherapy of CAD.

Role of Lipoprotein Levels and Function in Atherosclerosis Associated with Autoimmune Rheumatic Diseases

Immune and inflammatory mediators in autoimmune rheumatic diseases induce modification in the activity of enzymes pivotal for lipid metabolism and promote a proatherogenic serum lipid profile. However, disturbances in low- and high-density lipoprotein composition and increased lipid oxidation also occur. Therefore, lipoprotein dysfunction causes intracellular cholesterol accumulation in macrophages, smooth muscle cells, and platelets. Overall, both plaque progression and acute cardiovascular events are promoted. Single rheumatic diseases may present a particular pattern of lipid disturbances so that standard methods to evaluate cardiovascular risk may not be accurate enough. In general, antirheumatic drugs positively affect lipid metabolism in these patients.

Effects of lysosomal low density lipoprotein oxidation by ferritin on macrophage function

We have previously demonstrated that low density lipoprotein (LDL) can be oxidised by iron in the lysosomes of macrophages. Some of the iron content of lysosomes might be delivered through autophagy of ferritin (the main iron-storage protein in the body). We have now investigated the effects of ferritin-mediated LDL oxidation on macrophage function. The addition of ferritin to human THP-1 cells and human monocyte-derived macrophages increased lysosomal lipid peroxidation, as shown by LPO-Foam, a fluorescent probe targetted to lysosomes. Incubating THP-1 cells with ferritin and native LDL or LDL aggregated by sphingomyelinase, to allow their endocytosis and delivery to lysosomes, led to the formation of lysosomal ceroid (an advanced lipid oxidation product), indicative of lysosomal LDL oxidation. Incubating THP-1 cells with ferritin and LDL caused metabolic activation of the cells, as shown by increased extracellular acidification and oxygen consumption measured by a Seahorse analyser. LDL oxidised by ferritin in lysosomes might be released from macrophages when the cells die and lyse and affect neighbouring cells in atherosclerotic lesions. Adding LDL oxidised by ferritin at lysosomal pH (pH 4.5) to macrophages increased their intracellular reactive oxygen species formation, shown using dihydroethidium, and increased apoptosis. Ferritin might therefore contribute to LDL oxidation in the lysosomes of macrophages and have atherogenic effects.

Tackling Dyslipidemia in Obesity from a Nanotechnology Perspective

Obesity and dyslipidemia are the main features of metabolic syndrome, expressed mainly by adipose tissue dysfunction and connected by similar pathways and pharmacotherapy. Conventional drugs used in these two associated disorders are limited due to poor drug efficiency, non-specificity, and toxic side effects. Therefore, novel solutions for tackling obesity-associated diseases and providing insights into the development of innovative or improved therapies are necessary. Targeted nanotherapy is a revolutionary technology, offering a promising solution for combatting the disadvantages of currently available therapies for treating obesity and dyslipidemia due to its superior features, which include specific cell targeting, the protection of drugs against physiological degradation, and sustained drug release. This review presents a brief assessment of obesity and dyslipidemia, their impacts on human health, current treatment, and limitations, and the role and potential use of nanotechnology coupled with targeted drug delivery and nutraceuticals as emerging therapies. To the best of our knowledge, this paper presents, for the first time in the literature, a comparison between obesity and dyslipidemia nano-formulations based on drugs and/or natural extracts applied in experimental studies.

Ischemic Heart Disease in Patients with Inflammatory Bowel Disease: Risk Factors, Mechanisms and Prevention

According to new research, a possible association between inflammatory bowel disease (IBD) and an increased risk of ischemic heart disease (IHD) has been demonstrated, but this concern is still debatable. The purpose of this review is to investigate the link between IHD and IBD, as well as identify further research pathways that could help develop clinical recommendations for the management of IHD risk in IBD patients. There is growing evidence suggesting that disruption of the intestinal mucosal barrier in IBD is associated with the translocation of microbial lipopolysaccharides (LPS) and other endotoxins into the bloodstream, which might induce a pro-inflammatory cytokines response that can lead to endothelial dysfunction, atherosclerosis and acute cardiovascular events. Therefore, it is considered that the long-term inflammation process in IBD patients, similar to other chronic inflammatory diseases, may lead to IHD risk. The main cardiovascular risk factors, including high blood pressure, dyslipidemia, diabetes, smoking, and obesity, should be checked in all patients with IBD, and followed by strategies to reduce and manage early aggression. IBD activity is an important risk factor for acute cardiovascular events, and optimizing therapy for IBD patients should be followed as recommended in current guidelines, especially during active flares. Large long-term prospective studies, new biomarkers and scores are warranted to an optimal management of IHD risk in IBD patients.

Nitrotyrosine, Nitrated Lipoproteins, and Cardiovascular Dysfunction in Patients with Type 2 Diabetes: What Do We Know and What Remains to Be Explained?

Diabetes mellitus (DM) is a strong risk factor for the development of cardiovascular diseases (CVDs), which are the most important cause of morbidity and mortality in the population of patients living with DM. DM is associated with lipid metabolism disorders characterized by a decrease in the high-density lipoprotein blood concentration, an increase in the triglyceride blood concentration, and the presence of modified lipoproteins not routinely measured in clinical practice. Nitrated lipoproteins are produced by the nitration of the tyrosyl residues of apolipoproteins by myeloperoxidase. There is some evidence from the research conducted showing that nitrated lipoproteins may play a role in the development of cardiovascular dysfunction, but this issue requires further investigation. It was found that the nitration of HDL particles was associated with a decrease in caspase-3 and paraoxonase-1 activity, as well as a decrease in the activity of cholesterol transport via ABCA1, which reduces the protective effect of HDL particles on the cardiovascular system. Less information has been collected about the role of nitrated LDL particles. Thus far, much more information has been obtained on the relationship of nitrotyrosine expression with the presence of cardiovascular risk factors and the development of cardiovascular dysfunction. The purpose of this paper is to provide an extensive review of the literature and to present the most important information on the current state of knowledge on the association between nitrotyrosine and nitrated lipoproteins with dysfunction of the cardiovascular system, especially in patients living with DM. Moreover, directions for future research in this area were discussed.