Unraveling mechanisms of toxicant-induced oxidative stress in cardiovascular disease

Screening Antioxidant Components in Yiwei Decoction Using Spectrum-Effect Relationship and Network Pharmacology

Yiwei decoction (YWD) is a classic prescription with the function of nourishing stomach yin. In this study, the effective components of antioxidant activity of YWD and its possible mechanism were discussed from the point of view of spectral effect relationship and network pharmacology. Firstly, the fingerprints of 10 batches of YWD were established by UPLC-PDA technique, and the 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) scavenging rate and total antioxidant capacity (T-AOC) were used as the indicators for antioxidant activity in vitro. Then, the spectral effect relationship between the fingerprint profiles and antioxidant capacity was analyzed through grey relational analysis (GRA) and orthogonal projections to latent structures (OPLS). In addition, network pharmacology was employed to predict the potential mechanisms of YWD in the treatment of antioxidant-related diseases. The spectrum-effect relationship indicated that three common peaks were likely to be the most decisive active components, identified as verbascoside, psoralen, and vitexin, respectively. Based on network pharmacology analysis, a total of 83 target genes shared by the active components and antioxidant-related diseases were collected. AKT1, HSP90AA1, SRC, CASP3, and MTOR were closely related to antioxidant therapy and considered as core therapeutic targets. The potential mechanisms of YWD were obtained through gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Finally, molecular docking simulations were conducted to evaluate the binding activities between the core therapeutic targets and corresponding compounds. The excellent core protein-compound complexes obtained by molecular docking were simulated by molecular dynamics simulation. The results showed that the active compounds had good binding ability with the selected targets. This study successfully identified the effective components of YWD and predicted the potential targets and pathways, which provided a new idea for the application of YWD in the treatment of antioxidant stress in the future. In addition, the potential active components provide valuable implications for drug screening of related diseases.

Arsenic exposure promotes the emergence of cardiovascular diseases

A large number of studies conducted in the past decade 2010-2020 refer to the impact of arsenic (As) exposure on cardiovascular risk factors. The arsenic effect on humans is complex and mainly depends on the varying individual susceptibilities, its numerous toxic expressions and the variation in arsenic metabolism between individuals. In this review we present relevant data from studies which document the association of arsenic exposure with various biomarkers, the effect of several genome polymorphisms on arsenic methylation and the underling molecular mechanisms influencing the cardiovascular pathology. The corresponding results provide strong evidence that high and moderate-high As intake induce oxidative stress, inflammation and vessel endothelial dysfunction that are associated with increased risk for cardiovascular diseases (CVDs) and in particular hypertension, myocardial infarction, carotid intima-media thickness and stroke, ventricular arrhythmias and peripheral arterial disease. In addition, As exposure during pregnancy implies risks for blood pressure abnormalities among infants and increased mortality rates from acute myocardial infarction during early adulthood. Low water As concentrations are associated with increased systolic, diastolic and pulse pressure, coronary heart disease and incident stroke. For very low As concentrations the relevant studies are few. They predict a risk for myocardial infarction, stroke and ischemic stroke and incident CVD, but they are not in agreement regarding the risk magnitude.

Generation of potent Nrf2 activators via tuning the electrophilicity and steric hindrance of vinyl sulfones for neuroprotection

Oxidative stress is constantly involved in the etiopathogenesis of an ever-widening range of neurodegenerative diseases. As a consequence, effective repression of cellular oxidative stress to a redox homeostatic condition is a promising and feasible strategy to treat, or at least retard the progression of, such disorders. Nrf2, a primary orchestrator of cellular antioxidant response machine, is responsible for detoxifying and compensating for deleterious oxidative stress via transcriptional activation of a diverse array of antioxidant biomolecules. In the framework of our persistent interest in disclosing small molecules that interfere with cellular redox-regulating machinery, we report herein the synthesis, optimization, and biological assessment of 47 vinyl sulfone scaffold-bearing small molecules, most of which exhibit robust neuroprotective effect against H₂O₂-mediated lesions to PC12 cells. After initial screening, the most potent neuroprotective compounds 9b and 9c with marginal cytotoxicity were selected for the follow-up studies. Our results demonstrate that their neuroprotective effects are attributed to the up-regulation of a panel of antioxidant genes and corresponding gene products. Further mechanistic studies indicate that Nrf2 is indispensable for the cellular performances of 9b and 9c, arising from the fact that silence of Nrf2 gene drastically nullifies their protective action. Taken together, 9b and 9c discovered in this work merit further development as neuroprotective candidates for the treatment of oxidative stress-mediated pathological conditions.