Role of Thioredoxin in Age-Related Hypertension

Disulfide stress and its role in cardiovascular diseases

Cardiovascular disease (CVD) is one of the leading causes of mortality in humans, and oxidative stress plays a pivotal role in disease progression. This phenomenon typically arises from weakening of the cellular antioxidant system or excessive accumulation of peroxides. This review focuses on a specialized form of oxidative stress-disulfide stress-which is triggered by an imbalance in the glutaredoxin and thioredoxin antioxidant systems within the cell, leading to the accumulation of disulfide bonds. The genesis of disulfide stress is usually induced by extrinsic pathological factors that disrupt the thiol-dependent antioxidant system, manifesting as sustained glutathionylation of proteins, formation of abnormal intermolecular disulfide bonds between cysteine-rich proteins, or irreversible oxidation of thiol groups to sulfenic and sulfonic acids. Disulfide stress not only precipitates the collapse of the antioxidant system and the accumulation of reactive oxygen species, exacerbating oxidative stress, but may also initiate cellular inflammation, autophagy, and apoptosis through a cascade of signaling pathways. Furthermore, this review explores the detrimental effects of disulfide stress on the progression of various CVDs including atherosclerosis, hypertension, myocardial ischemia-reperfusion injury, diabetic cardiomyopathy, cardiac hypertrophy, and heart failure. This review also proposes several potential therapeutic avenues to improve the future treatment of CVDs.

Redox Regulation of K+ channel: Role of Thioredoxin

SIGNIFICANCE

Potassium channels regulate the influx and efflux of K+ ions in various cell types that generate and propagate action potential associated with excitation, contraction and relaxation of various cell types. Although redox active cysteines are critically important for channel activity, redox regulation of K+ channels by thioredoxin has not been systematically reviewed.

RECENT ADVANCES

Redox regulation of K+ channel is now increasingly recognized as drug targets in pathological condition of several cardiovascular disease processes. The role of thioredoxin in regulation of these channels and its implication in pathological conditions have not been adequately reviewed. This review specifically focuses on the redox-regulatory role of thioredoxin on K+ channel structure and function in physiological and pathophysiological conditions.

CRITICAL ISSUES

Ion channels including K+ channel have been implicated in the functioning of cardiomyocyte excitation-contraction coupling, vascular hyperpolarization, cellular proliferation, and neuronal stimulation in physiological and pathophysiological conditions. Although, oxidation-reduction of ion channels is critically important in their function, role of thioredoxin, redox regulatory protein in regulation of these channels and its implication in pathological conditions need to be studied to gain further insight into channel function.

FUTURE DIRECTIONS

Future studies need to map all redox regulatory pathways in channel structure and function using novel mouse models, redox proteomic and signal transduction studies, which modulate various currents and altered excitability of relevant cells implicated in a pathological condition. We are yet at infancy of studies related to redox control of various K+ channels and structured and focused studies with novel animal models.

ROS: Basic Concepts, Sources, Cellular Signaling, and its Implications in Aging Pathways

Reactive oxygen species (ROS) are bioproducts of cellular metabolism. There is a range of molecules with oxidizing properties known as ROS. Despite those molecules being implied negatively in aging and numerous diseases, their key role in cellular signaling is evident. ROS control several biological processes such as inflammation, proliferation, and cell death. The redox signaling underlying these cellular events is one characteristic of the new generation of scientists aimed at defining the role of ROS in the cellular environment. The control of redox potential, which includes the balance of the sources of ROS and the antioxidant system, implies an important target for understanding the cells' fate derived from redox signaling. In this review, we summarized the chemical, the redox balance, the signaling, and the implications of ROS in biological aging.

Hypertension and Its Associated Factors Among Long-Distance Truck Drivers in Ethiopia

Introduction

Hypertension is rising globally and is one of the leading causes of cardiovascular disease. It affects people of different groups; however, owing to a rise in a sedentary lifestyle it is more prevalent among long-distance truck drivers. However, the prevalence of hypertension and its associated factors among truck drivers in Ethiopia is not known. Therefore, this study aimed to determine the prevalence of hypertension and its associated factors among long-distance truck drivers in Ethiopia.

Methods

A cross-sectional study was conducted among 415 long-distance truck drivers selected by systematic random sampling technique at Modjo dry port from May 15 to 30, 2021. The data were collected and entered into Epi-data 4.6 then it was exported to SPSS version 25 for analysis. Descriptive statistics, bivariable, and multivariable logistic regression analyses were executed. The odds ratio with a 95% confidence interval was computed. In the final model, a variable with a p ≤ 0.05 was declared as a predictor of hypertension.

Results

The prevalence of hypertension among long-distance truck drivers in Ethiopia was 34.7%. The odds of hypertension was higher among drivers who were ≥45 years old [Adjusted odds ratio (AOR) = 4.32; 95% Confidence interval (CI): 2.16, 8.62], obese [AOR= 5.12; 95% CI: 1.33, 19.8], alcohol drinkers [AOR=3.05; 95% CI: 1.27, 7.31], and cigarette smokers [AOR= 3.74; 95% CI: 1.64, 8.51]. Drivers who had regular physical exercise were less likely [AOR=0.33; 95% CI: 0.17, 0.63] to have hypertension than drivers with no physical activity.

Conclusion

More than a third of the participants in Ethiopia had hypertension. Higher age, obesity, absence of rest between driving, short sleep duration, smoking, alcohol drinking, and physical inactivity were significantly associated with hypertension. Therefore, health education on lifestyle modifications, sleep habits, and the importance of rest breaks between driving should be considered to prevent hypertension and further complications.

Revisiting pharmacology of oxidative stress and endothelial dysfunction in cardiovascular disease: Evidence for redox-based therapies

According to the latest Global Burden of Disease Study data, non-communicable diseases in general and cardiovascular disease (CVD) in particular are the leading cause of premature death and reduced quality of life. Demographic shifts, unhealthy lifestyles and a higher burden of adverse environmental factors provide an explanation for these findings. The expected growing prevalence of CVD requires enhanced research efforts for identification and characterisation of novel therapeutic targets and strategies. Cardiovascular risk factors including classical (e.g. hypertension, diabetes, hypercholesterolaemia) and non-classical (e.g. environmental stress) factors induce the development of endothelial dysfunction, which is closely associated with oxidant stress and vascular inflammation and results in CVD, particularly in older adults. Most classically successful therapies for CVD display vasoprotective, antioxidant and anti-inflammatory effects, but were originally designed with other therapeutic aims. So far, only a few 'redox drugs' are in clinical use and many antioxidant strategies have not met expectations. With the present review, we summarise the actual knowledge on CVD pathomechanisms, with special emphasis on endothelial dysfunction, adverse redox signalling and oxidative stress, highlighting the preclinical and clinical evidence. In addition, we provide a brief overview of established CVD therapies and their relation to endothelial dysfunction and oxidative stress. Finally, we discuss novel strategies for redox-based CVD therapies trying to explain why, despite a clear link between endothelial dysfunction and adverse redox signalling and oxidative stress, redox- and oxidative stress-based therapies have not yet provided a breakthrough in the treatment of endothelial dysfunction and CVD.

Development a clinical prediction model of the neurological outcome for patients with coma and survived 24 hours after cardiopulmonary resuscitation

Background

Cardiac arrest is still a global public health problem at present. The neurological outcome is the core indicator of the prognosis of cardiac arrest. However, there is no effective means or tools to predict the neurological outcome of patients with coma and survived 24 hours after successful cardiopulmonary resuscitation (CPR).

Hypothesis

Therefore, we expect to construct a prediction model to predict the neurological outcome for patients with coma and survived 24 hours after successful CPR.

Methods

A retrospective cohort study was used to construct a prediction model of the neurological function for patients with coma and survived 24 hours after successful CPR. From January 2007 to December 2015, a total of 262 patients met the inclusion and exclusion criteria.

Results

The predictive model was developed using preselected variables by a systematic review of the literature. Finally, we get five sets of models (three sets of construction models and two sets of internal verification models) which with similar predictive value. The stepwise model, which including seven variables (age, noncardiac etiology, nonshockable rhythm, bystander CPR, total epinephrine dose, APTT, and SOFA score), was the simplest model, so we choose it as our final predictive model. The area under the ROC curve (AUC), specificity, and sensitivity of the stepwise model were respectively 0.82 (0.77, 0.87), 0.72and 0.82. The AUC, specificity, and sensitivity of the bootstrap stepwise (BS stepwise) model were respectively 0.82 (0.77, 0.87), 0.71, and 0.82.

Conclusion

This new and validated predictive model may provide individualized estimates of neurological function for patients with coma and survived 24 hours after successful CPR using readily obtained clinical risk factors. External validation studies are required further to demonstrate the model's accuracy in diverse patient populations.

Anti-Allergic and Anti-Inflammatory Effects and Molecular Mechanisms of Thioredoxin on Respiratory System Diseases

Significance: The pathogenesis and progression of allergic inflammation in the respiratory system are closely linked to oxidative stress. Thioredoxin (TRX) is an essential redox balance regulator in organisms and is induced by various oxidative stress factors, including ultraviolet rays, radiation, oxidation, viral infections, ischemia reperfusion, and anticancer agents. Recent Advances: We demonstrated that systemic administration and transgenic overexpression of TRX is useful in a wide variety of in vivo inflammatory respiratory diseases models, such as viral pneumonia, interstitial lung disease, chronic obstructive pulmonary disease, asthma, acute respiratory distress syndrome, and obstructive sleep apnea syndrome, by removing reactive oxygen species, blocking production of inflammatory cytokines, inhibiting migration and activation of neutrophils and eosinophils, and regulating the cellular redox status. In addition, TRX's anti-inflammatory mechanism is different from the mechanisms associated with anti-inflammatory agents, such as glucocorticoids, which regulate the inflammatory reaction in association with suppressing immune responses. Critical Issues: Understanding the molecular mechanism of TRX is very helpful for understanding the role of TRX in respiratory diseases. In this review, we show the protective effect of TRX in various respiratory diseases. In addition, we discuss its anti-allergic and anti-inflammatory molecular mechanism in detail. Future Directions: The application of TRX may be useful for treating respiratory allergic inflammatory disorders. Antioxid. Redox Signal. 32, 785-801.