N-Acetylcysteine and Atherosclerosis: Promises and Challenges

Trends in drug repurposing: Advancing cardiovascular disease management in geriatric populations

Drug repurposing is a promising strategy for managing cardiovascular disease (CVD) in geriatric populations, offering efficient and cost-effective solutions. CVDs are prevalent across all age groups, with a significant increase in prevalence among geriatric populations. The middle-age period (40-65 years) is critical due to factors like obesity, sedentary lifestyle, and psychosocial stress. In individuals aged 65 and older, the incidence of CVDs is highest due to age-related physiological changes and prolonged exposure to risk factors. In this review we find that certain drugs, such as non-cardiovascular drugs like anakinra, probenecid, N-acetyl cysteine, quercetin, resveratrol, rapamycin, colchicine, bisphosphonates, hydroxychloroquine, SGLT-2i drugs, GLP-1Ras drugs and sildenafil are recommended for drug repurposing to achieve cardiovascular benefits in geriatric patients. However, agents such as canakinumab, methotrexate, ivermectin, erythromycin, capecitabine, carglumic acid, chloroquine, and furosemide are constrained in their therapeutic use and warrant meticulous consideration, rendering them less favorable for this specific application. This review emphasizes the importance of exploring alternative therapeutic strategies to improve outcomes in geriatric populations and suggests drug repurposing as a promising avenue to enhance treatment efficacy.

6PPD induces cerebrovascular defects by triggering oxidative stress and ferroptosis in zebrafish

N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), which is widely used as an antiozonant in rubber tires, has recently got much attention for its acute aquatic toxicity. However, the developmental toxicity of 6PPD in cerebrovascular network remains unknown. Here, we investigated the effects of 6PPD exposure in cerebral vascular using zebrafish. 6PPD would not affect the body length and shape of zebrafish larvae at the concentrations ranging from 20 μg/L to 1000 μg/L. 6PPD induced developmental defects in the brain in a concentration-dependent manner. The trunk vascular development would not be affected while the cerebrovascular network was disrupted upon 6PPD exposure. 6PPD would trigger excessive Reactive Oxygen Species (ROS) in the brain, indicating abnormal oxidative stress. Mechanistically, brain-specific transcriptome analysis showed that 6PPD could potentially cause the blockage of arachidonic acid (AA) metabolism-related genes and the upregulation of ferroptosis-related genes. Besides, treatment with ferroptosis inhibitor N-Acetyl-L-cysteine (NAC) attenuated oxidative damage and improved the construction of cerebrovascular network upon 6PPD exposure. Moreover, using a human vascular endothelial cell line, we further confirmed that 6PPD could trigger abnormal oxidative stress and defective expansion capacity, implying the conserved toxicity cross species. These findings are useful for the elucidation of toxicity underlying 6PPD in cerebrovascular systems of both zebrafish and humans.

Efficacy of N-Acetylcysteine as an Adjuvant Therapy for Rheumatoid Arthritis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Aims/Background Rheumatoid arthritis (RA) is an inflammatory autoimmune disease and N-acetylcysteine (NAC) is considered a potential therapeutic agent for RA due to strong antioxidant and anti-inflammatory properties. Therefore, this systematic review and meta-analysis aimed to evaluate the efficacy of NAC as an adjuvant therapy for RA. Methods A systematic search was conducted across five databases from inception to 1 August 2024, including CINAHL, Cochrane Library, EMBASE, PubMed, and Web of Science. The Cochrane risk-of-bias tool for randomized trials was used to assess the quality of the included studies. Sensitivity analysis was performed when significant heterogeneity was identified. Results Four studies involving 204 patients were included in our meta-analysis. The results indicated that NAC alleviated disease activity in RA patients (Disease Activity Score 28-erythrocyte sedimentation rate (DAS28-ESR): mean difference (MD) = 0.54). Additionally, NAC reduced inflammatory markers (erythrocyte sedimentation rate (ESR): MD = 3.00). However, the beneficial effects of NAC on oxidative stress in RA patients were not observed. Conclusion This meta-analysis demonstrated the efficacy of NAC in reducing inflammatory markers, improving joint tenderness, and swelling in patients with RA.

Interplay of Reactive Oxygen Species (ROS) and Epigenetic Remodelling in Cardiovascular Diseases Pathogenesis: A Contemporary Perspective

Cardiovascular diseases (CVDs) continue to be the leading cause of mortality worldwide, necessitating the development of novel therapies. Despite therapeutic advancements, the underlying mechanisms remain elusive. Reactive oxygen species (ROS) show detrimental effects at high concentrations but act as essential signalling molecules at physiological levels, playing a critical role in the pathophysiology of CVD. However, the link between pathologically elevated ROS and CVDs pathogenesis remains poorly understood. Recent research has highlighted the remodelling of the epigenetic landscape as a crucial factor in CVD pathologies. Epigenetic changes encompass alterations in DNA methylation, post-translational histone modifications, adenosine triphosphate (ATP)-dependent chromatin modifications, and noncoding RNA transcripts. Unravelling the intricate link between ROS and epigenetic changes in CVD is challenging due to the complexity of epigenetic signals in gene regulation. This review aims to provide insights into the role of ROS in modulating the epigenetic landscape within the cardiovascular system. Understanding these interactions may offer novel therapeutic strategies for managing CVD by targeting ROS-induced epigenetic changes. It has been widely accepted that epigenetic modifications are established during development and remain fixed once the lineage-specific gene expression pattern is achieved. However, emerging evidence has unveiled its remarkable dynamism. Consequently, it is now increasingly recognized that epigenetic modifications may serve as a crucial link between ROS and the underlying mechanisms implicated in CVD.

Drug conjugates crosslinked bioresponsive hydrogel for combination therapy of diabetic wound

Basic fibroblast growth factor (bFGF) has proved to be effective for wound healing, yet its effectiveness is extremely retarded in diabetic wounds due to the severe oxidative stress in wound beds. To solve this issue, herein a novel combination therapy of bFGF and N-acetylcysteine (NAC, antioxidant) was devised for improved diabetic wound repair. To avoid rapid loss of both drugs in the wound beds, a bioresponsive hydrogel (bFGF-HSPP-NAC) was engineered by incorporating bFGF and NAC into polymer-drug conjugates (HSPP) via thiol-disulfide exchange reactions. In response to oxidative stress (e.g., reactive oxygen species), the disulfide bonds (SS) within the hydrogel are broken into thiol groups (-S-H), thereby promoting hydrogel degradation and enabling controlled drug release. Initially, NAC is released to scavenge free radicals and ameliorate oxidative damage. Subsequently, bFGF is released to expedite tissue regeneration. This combinatorial strategy is tailored to the specific characteristics of the wound microenvironment at various stages of diabetic wound healing, thereby achieving therapeutic efficacy. The results indicate that the bFGF-HSPP-NAC hydrogel markedly enhances re-epithelialization, collagen deposition, hair follicle regeneration, and neovascularization. In conclusion, the bioresponsive bFGF-HSPP-NAC hydrogel demonstrates significant potential for application in combinatorial therapeutic approaches for diabetic wound healing.

Serum metabolites and hypercholesterolemia: insights from a two-sample Mendelian randomization study

Background

Hypercholesterolemia, a critical contributor to cardiovascular disease, is not fully understood in terms of its relationship with serum metabolites and their role in disease pathogenesis.

Methods

This study leveraged GWAS data to explore the relationship between serum metabolites and hypercholesterolemia, pinpointing significant metabolites via Mendelian Randomization (MR) and KEGG pathway enrichment analysis. Data on metabolites were sourced from a European population, with analysis focusing on individuals diagnosed with hypercholesterolemia.

Results

Out of 486 metabolites analyzed, ten showed significant associations with hypercholesterolemia, categorized into those enhancing risk and those with protective effects. Specifically, 2-methoxyacetaminophen sulfate and 1-oleoylglycerol (1-monoolein) were identified as risk-enhancing, with odds ratios (OR) of 1.545 (95% CI: 1.230-1.939; P_FDR = 3E-04) and 1.462 (95% CI: 1.036-2.063; P_FDR = 0.037), respectively. On the protective side, 3-(cystein-S-yl)acetaminophen, hydroquinone sulfate, and 2-hydroxyacetaminophen sulfate demonstrated ORs of 0.793 (95% CI: 0.735-0.856; P_FDR = 6.18E-09), 0.641 (95% CI: 0.423-0.971; P_FDR = 0.042), and 0.607 (95% CI: 0.541-0.681; P_FDR = 5.39E-17), respectively. In addition, KEGG pathway enrichment analysis further revealed eight critical pathways, comprising "biosynthesis of valine, leucine, and isoleucine", "phenylalanine metabolism", and "pyruvate metabolism", emphasizing their significant role in the pathogenesis of hypercholesterolemia.

Conclusion

This study underscores the potential causal links between particular serum metabolites and hypercholesterolemia, offering innovative viewpoints on the metabolic basis of the disease. The identified metabolites and pathways offer promising targets for therapeutic intervention and warrant further investigation.

A Non-Coronary, Peripheral Arterial Atherosclerotic Disease (Carotid, Renal, Lower Limb) in Elderly Patients-A Review PART II-Pharmacological Approach for Management of Elderly Patients with Peripheral Atherosclerotic Lesions outside Coronary Territory

BACKGROUND

Aging is a key risk factor for atherosclerosis progression that is associated with increased incidence of ischemic events in supplied organs, including stroke, coronary events, limb ischemia, or renal failure. Cardiovascular disease is the leading cause of death and major disability in adults ≥ 75 years of age. Atherosclerotic occlusive disease affects everyday activity, quality of life, and it is associated with reduced life expectancy. As most multicenter randomized trials exclude elderly and very elderly patients, particularly those with severe comorbidities, physical or cognitive dysfunctions, frailty, or residence in a nursing home, there is insufficient data on the management of older patients presenting with atherosclerotic lesions outside coronary territory. This results in serious critical gaps in knowledge and a lack of guidance on the appropriate medical treatment. In addition, due to a variety of severe comorbidities in the elderly, the average daily number of pills taken by octogenarians exceeds nine. Polypharmacy frequently results in drug therapy problems related to interactions, drug toxicity, falls with injury, delirium, and non-adherence. Therefore, we have attempted to gather data on the medical treatment in patients with extra-cardiac atherosclerotic lesions indicating where there is some evidence of the management in elderly patients and where there are gaps in evidence-based medicine. Public PubMed databases were searched to review existing evidence on the effectiveness of lipid-lowering, antithrombotic, and new glucose-lowering medications in patients with extra-cardiac atherosclerotic occlusive disease.

Reactive Carbonyl Species and Protein Lipoxidation in Atherogenesis

Atherosclerosis is a multifactorial disease of medium and large arteries, characterized by the presence of lipid-rich plaques lining the intima over time. It is the main cause of cardiovascular diseases and death worldwide. Redox imbalance and lipid peroxidation could play key roles in atherosclerosis by promoting a bundle of responses, including endothelial activation, inflammation, and foam cell formation. The oxidation of polyunsaturated fatty acids generates various lipid oxidation products such as reactive carbonyl species (RCS), including 4-hydroxy alkenals, malondialdehyde, and acrolein. RCS covalently bind to nucleophilic groups of nucleic acids, phospholipids, and proteins, modifying their structure and activity and leading to their progressive dysfunction. Protein lipoxidation is the non-enzymatic post-translational modification of proteins by RCS. Low-density lipoprotein (LDL) oxidation and apolipoprotein B (apoB) modification by RCS play a major role in foam cell formation. Moreover, oxidized LDLs are a source of RCS, which form adducts on a huge number of proteins, depending on oxidative stress intensity, the nature of targets, and the availability of detoxifying systems. Many systems are affected by lipoxidation, including extracellular matrix components, membranes, cytoplasmic and cytoskeletal proteins, transcription factors, and other components. The mechanisms involved in lipoxidation-induced vascular dysfunction are not fully elucidated. In this review, we focus on protein lipoxidation during atherogenesis.

A Comprehensive Review on the Significance of Cysteine in Various Metabolic Disorders; Particularly CVD, Diabetes, Renal Dysfunction, and Ischemic Stroke

Metabolic disorders have long been a challenge for medical professionals and are a leading cause of mortality in adults. Diabetes, cardiovascular disorders (CVD), renal dysfunction, and ischemic stroke are the most prevalent ailments contributing to a high mortality rate worldwide. Reactive oxygen species are one of the leading factors that act as a fundamental root cause of metabolic syndrome. All of these disorders have their respective treatments, which, to some degree, sabotage the pathological worsening of the disease and an inevitable death. However, they pose a perilous health hazard to humankind. Cysteine, a functional amino acid shows promise for the prevention and treatment of metabolic disorders, such as CVD, Diabetes mellitus, renal dysfunction, and ischemic stroke. In this review, we explored whether cysteine can eradicate reactive oxygen species and subsequently prevent and treat these diseases.