Oxidative stress and inflammation as central mediators of atrial fibrillation in obesity and diabetes

Frailty Predicts Incident Atrial Fibrillation in Women but Not in Men: The Kuopio Ischaemic Heart Disease Risk Factor Study

INTRODUCTION

Frailty and atrial fibrillation (AF) are common aging problems and increasing globally. The association(s) between frailty and AF has been inconclusive. The purpose of this prospective population-based cohort was to investigate the associations between frailty and incident AF in older men and women.

METHODS

In total 839 participants, women (n = 458) and men (n = 381), aged 61-74 years from the Kuopio Ischaemic Heart Disease Risk Factor Study were included (March 1, 1998, to December 31, 2001). At the baseline, frailty prevalence was 49.3% (n = 414), and non-frailty 50.7% (n = 425) of the total population. Frailty was ascertained with the presence of 3-5 and prefrailty 1-2 of the following criteria: weight loss (highest 20% over 7 years), self-reported tiredness, weakness (measured by handgrip strength), slow walking speed (walking pace), and low physical activity (lowest 20%). AF events were obtained by record linkages from the national computerized hospitalization registry in Finland up to December 31, 2019. Multivariate Cox proportional hazard regression estimated the hazard ratio (HR) of incident events, adjusted for potential confounders.

RESULTS

During the mean follow-up of 14.2 years, 288 AF cases (169 women; 119 men) occurred. After adjustment for possible confounders, the HRs (95% confidence intervals [CIs]) for AF was 1.46 (1.48-1.85) in the frail population, compared to the non-frail group. The association was observed only among older frail women (multivariable-adjusted HR 1.78, 95% CI [1.28-2.48]) (p for interaction = 0.04). No statistically significant associations were observed between frailty and future AF incident among men (multivariable-adjusted HRs 1.12, 95% CI (0.77-1.63)).

CONCLUSIONS

In this population-based epidemiological cohort, the risk of developing AF was increased in women affected by frailty at baseline but not in men.

ORal anticoaGulants in diAbetic and Nondiabetic patients with nOn-valvular atrial fibrillatioN (ORGANON)

BACKGROUND

Diabetes represents a pro-thrombotic condition.

OBJECTIVES

The primary objective was to evaluate the effects of Vitamin K Antagonist (VKA) compared to direct oral anticoagulants (DOACs) in diabetic and nondiabetic patients with non-valvular atrial fibrillation, newly diagnosed. The secondary objective was to evaluate the effects on the risk of bleeding.

METHODS

We enrolled 300 patients with newly diagnosed atrial fibrillation. One hundred and sixteen patients were taking warfarin, 31 acenocumarol, 22 dabigatran, 80 rivaroxaban, 34 apixaban, and 17 edoxaban. We evaluated: anthropometric parameters, glycated hemoglobin (HbA1c), fasting and post-prandial glucose (FPG, and PPG), lipid profile, Lp(a), small and dense low-density lipoprotein (SD-LDL), oxidized LDL (Ox-LDL), I-troponin (I-Tn), creatinine, transaminases, iron, red blood cells (RBC); hemoglobin (Hb), platelets (PLT), fibrinogen, D-dimer, anti-thrombin III, C-reactive protein (Hs-CRP), Metalloproteinases-2 (MMP-2), Metalloproteinases-9 (MMP-9), and incidence of bleeding.

RESULTS

We did not record any differences among nondiabetic patients between VKA and DOACs. However, when we considered diabetic patients, we found a slight, but significant improvement of triglycerides and SD-LDL. As regards incidence of bleeding, minor bleeding was more frequent in VKA diabetic group compared to DOACs diabetic group; furthermore, the incidence of major bleeding was higher with VKA in nondiabetic and diabetic group, compared to patients with DOACs. Among DOACs, we recorded a higher incidence of bleeding (minor and major) with dabigatran compared to rivaroxaban, apixaban and edoxaban in nondiabetic and diabetic patients.

CONCLUSION

DOACs seem to be metabolically favourable in diabetic patients. Regarding incidence of bleeding, DOACs with the exception of dabigatran, seem better than VKA in diabetic patients.

Obesity-Related Atrial Fibrillation: Cardiac Manifestation of a Systemic Disease

Atrial fibrillation (AF) is the most common arrhythmia worldwide and is associated with increased morbidity and mortality. The mechanisms underlying AF are complex and multifactorial. Although it is well known that obesity is a strong risk factor for AF, the mechanisms underlying obesity-related AF are not completely understood. Current evidence proposes that in addition to overall hemodynamic changes due to increased body weight, excess adiposity raises systemic inflammation and oxidative stress, which lead to adverse atrial remodeling. This remodeling includes atrial fibrosis, atrial dilation, decreased electrical conduction between atrial myocytes, and altered ionic currents, making atrial tissue more vulnerable to both the initiation and maintenance of AF. However, much remains to be learned about the mechanistic links between obesity and AF. This knowledge will power the development of novel diagnostic tools and treatment options that will help combat the rise of the global AF burden among the obesity epidemic.

Obesity and atrial fibrillation: a narrative review from arrhythmogenic mechanisms to clinical significance

The prevalence of obesity and atrial fibrillation (AF), which are inextricably linked, is rapidly increasing worldwide. Obesity rates are higher among patients with AF than healthy individuals. Some epidemiological data indicated that obese patients were more likely to develop AF, but others reported no significant correlation. Obesity-related hypertension, diabetes, and obstructive sleep apnea are all associated with AF. Additionally, increased epicardial fat, systemic inflammation, and oxidative stress caused by obesity can induce atrial enlargement, inflammatory activation, local myocardial fibrosis, and electrical conduction abnormalities, all of which led to AF and promoted its persistence. Weight loss reduced the risk and reversed natural progression of AF, which may be due to its anti-fibrosis and inflammation effect. However, fluctuations in weight offset the benefits of weight loss. Therefore, the importance of steady weight loss urges clinicians to incorporate weight management interventions in the treatment of patients with AF. In this review, we discuss the epidemiology of obesity and AF, summarize the mechanisms by which obesity triggers AF, and explain how weight loss improves the prognosis of AF.

Association of Dietary Inflammatory Index and Dietary Oxidative Balance Score with All-Cause and Disease-Specific Mortality: Findings of 2003-2014 National Health and Nutrition Examination Survey

To clarify the effects of dietary inflammatory and pro-oxidative potential, we investigated the impact of the Dietary Inflammation Index (DII) and the Dietary Oxidative Balance Score (DOBS) on all-cause and disease-specific mortality. For DII and DOBS, 17,550 and 24,527 participants were included. Twenty-six and seventeen dietary factors were selected for scoring. Cox proportional hazards regression models were used. DII and DOBS were significantly associated with all-cause, CVD, and cancer mortality in this nationally representative sample of American adults. Compared with the lowest DII, the multivariable-adjusted hazard ratios (95% CI) of all-cause, CVD, and cancer mortality for the highest were 1.49 (1.23-1.80), 1.58 (1.08-2.33), and 1.56 (1.07-2.25). The highest quartile of DOBS was associated with the risk of all-cause death (HR 0.71, 95% CI 0.59-0.86). Pro-inflammatory and pro-oxidative diets were associated with increased risk for all-cause (HR 1.59, 95% CI 1.28-1.97), and CVD (HR 2.29, 95% CI 1.33-3.94) death compared to anti-inflammatory and antioxidant diets. Similar results were observed among the stratification analyses. Inflammation-reducing and oxidative-balancing diets are linked to lower all-cause and CVD mortality. Diets impact health by regulating inflammation and oxidative stress.

An Exploration of the Relationship Between Atrial Fibrillation and Obesity

In the past 40 years, the prevalence of atrial fibrillation and obesity have skyrocketed. It has long been established that obesity can lead to adverse cardiovascular outcomes due to its myriad of effects on cardiovascular architecture, cardiovascular hemodynamics, and electrical conduction interference. The goal of this article is to explore the pathogenesis of atrial fibrillation in obese patients and examine the role of atrial enlargement, increased adipose deposits surrounding the pericardium, interstitial fibrosis, and inflammation in the development and worsening of atrial fibrillation in obese patients.

General Anesthetic Care of Obese Patients Undergoing Surgery: A Review of Current Anesthetic Considerations and Recent Advances

Obesity has long been linked to adverse health effects over time. As the prevalence of obesity continues to rise, it is important to anticipate and minimize the complications that obesity brings in the anesthesia setting during surgery. Anesthetic departments must recognize the innumerable risks when managing patients with obesity undergoing surgery, including anatomical and physiological changes as well as comorbidities such as diabetes, cardiovascular diseases, and malignancies. Therefore, the purpose of this review is to analyze the current literature and evaluate the current and recent advances in anesthetic care of obese patients undergoing surgery, to better understand the specific challenges this patient population faces. A greater understanding of the differences between anesthetic care for obese patients can help to improve patient care and the specificity of treatment. The examination of the literature will focus on differing patient outcomes and safety precautions in obese patients as compared to the general population. Specifically highlighting the differences in pre-operative, intra-operative, and post-operative care, with the aim to identify issues and present possible solutions.

The role of monocytes in thrombotic diseases: a review

Cardiovascular and cerebrovascular diseases are the number one killer threatening people's life and health, among which cardiovascular thrombotic events are the most common. As the cause of particularly serious cardiovascular events, thrombosis can trigger fatal crises such as acute coronary syndrome (myocardial infarction and unstable angina), cerebral infarction and so on. Circulating monocytes are an important part of innate immunity. Their main physiological functions are phagocytosis, removal of injured and senescent cells and their debris, and development into macrophages and dendritic cells. At the same time, they also participate in the pathophysiological processes of pro-coagulation and anticoagulation. According to recent studies, monocytes have been found to play a significant role in thrombosis and thrombotic diseases of the immune system. In this manuscript, we review the relationship between monocyte subsets and cardiovascular thrombotic events and analyze the role of monocytes in arterial thrombosis and their involvement in intravenous thrombolysis. Finally, we summarize the mechanism and therapeutic regimen of monocyte and thrombosis in hypertension, antiphospholipid syndrome, atherosclerosis, rheumatic heart disease, lower extremity deep venous thrombosis, and diabetic nephropathy.

Natural products targeting inflammation-related metabolic disorders: A comprehensive review

Currently, the incidence of metabolic disorders is increasing, setting a challenge to global health. With major advancement in the diagnostic tools and clinical procedures, much has been known in the etiology of metabolic disorders and their corresponding pathophysiologies. In addition, the use of in vitro and in vivo experimental models prior to clinical studies has promoted numerous biomedical breakthroughs, including in the discovery and development of drug candidates to treat metabolic disorders. Indeed, chemicals isolated from natural products have been extensively studied as prospective drug candidates to manage diabetes, obesity, heart-related diseases, and cancer, partly due to their antioxidant and anti-inflammatory properties. Continuous efforts have been made in parallel to improve their bioactivity and bioavailability using selected drug delivery approaches. Here, we provide insights on recent progress in the role of inflammatory-mediated responses on the initiation of metabolic disorders, with particular reference to diabetes mellitus, obesity, heart-related diseases, and cancer. In addition, we discussed the prospective role of natural products in the management of diabetes, obesity, heart-related diseases, and cancers and provide lists of potential biological targets for high throughput screening in drug discovery and development. Lastly, we discussed findings observed in the preclinical and clinical studies prior to identifying suitable approaches on the phytochemical drug delivery systems that are potential to be used in the treatment of metabolic disorders.

Five blueberry anthocyanins and their antioxidant, hypoglycemic, and hypolipidemic effects in vitro

The dual epidemic of obesity and diabetes mellitus is becoming an important worldwide public health issue. "Diabesity" is the term used to describe the combined detrimental health effects of both diabetes mellitus and obesity/overweight. Currently, food-derived bioactive compounds are suggested to alleviate diabesity. Blueberries are rich in bioactive anthocyanins, which are associated with contributing to preventing obesity and diabetes mellitus. However, the accurate active compounds and the underlying mechanism are still unclear. The objective of this study was to investigate the beneficial effects of blueberry anthocyanin on diabesity. In total, five anthocyanins (delphinidin-3-O-galactoside, delphinidin-3-O-glucoside, petunidin-3-O-galactoside, petunidin-3-O-glucoside, and malvidin-3-O-galactoside) were isolated from rabbiteye blueberry (Vaccinium virgatum) cultivar "Garden blue." All these anthocyanins exhibited oxygen radical absorbance capacity (ORAC), scavenging power of ABTS⁺, and DPPH-free radical and inhibitory activity of α-glucosidase in vitro. Moreover, some compounds improved glucose uptake and attenuated lipid accumulation in high glucose and oleic acid-treated HepG2 cells. All these results suggest that blueberry anthocyanins have potential antioxidant, hypoglycemic, and hypolipidemic effects, which may benefit the treatment of diabesity.

Biomarkers of Atrial Fibrillation Recurrence in Patients with Paroxysmal or Persistent Atrial Fibrillation Following External Direct Current Electrical Cardioversion

Atrial fibrillation (AF) is associated with atrial remodeling, cardiac dysfunction, and poor clinical outcomes. External direct current electrical cardioversion is a well-developed urgent treatment strategy for patients presenting with recent-onset AF. However, there is a lack of accurate predictive serum biomarkers to identify the risks of AF relapse after electrical cardioversion. We reviewed the currently available data and interpreted the findings of several studies revealing biomarkers for crucial elements in the pathogenesis of AF and affecting cardiac remodeling, fibrosis, inflammation, endothelial dysfunction, oxidative stress, adipose tissue dysfunction, myopathy, and mitochondrial dysfunction. Although there is ample strong evidence that elevated levels of numerous biomarkers (such as natriuretic peptides, C-reactive protein, galectin-3, soluble suppressor tumorigenicity-2, fibroblast growth factor-23, turn-over collagen biomarkers, growth differential factor-15) are associated with AF occurrence, the data obtained in clinical studies seem to be controversial in terms of their predictive ability for post-cardioversion outcomes. Novel circulating biomarkers are needed to elucidate the modality of this approach compared with conventional predictive tools. Conclusions: Biomarker-based strategies for predicting events after AF treatment require extensive investigation in the future, especially in the presence of different gender and variable comorbidity profiles. Perhaps, a multiple biomarker approach exerts more utilization for patients with different forms of AF than single biomarker use.

The effects of fine particulate matter, solid fuel use and greenness on the risks of diabetes in middle-aged and older Chinese

BACKGROUND

Previous studies provided clues that environmental factors were closely related to diabetes incidence. However, the evidence from high-quality and large cohort studies about the effects of PM_2.5, solid fuel use and greenness on the development of diabetes among middle-aged and older adults in China was scarce.

OBJECTIVE

To separately investigate the independent effects of PM_2.5, solid fuel use and greenness on the development of diabetes among middle-aged and older adults.

METHODS

A total of 9242 participants were involved in this study extracted from the China Health and Retirement Longitudinal Study. Time-varying Cox regression was applied to detect the association of diabetes with PM_2.5, solid fuel use and greenness, separately. The potential interactive effect of air pollution and greenness were explored using the relative excess risk due to interaction (RERI).

RESULTS

Per 10 μg/m³ increases in PM_2.5 were associated with 6.0% (95% CI: 1.9, 10.2) increasing risks of diabetes incidence. Females seemed to be more susceptible to PM_2.5. However, the effects of solid fuel use only existed in older and lower BMI populations, with hazard ratios (HRs) of 1.404 (1.116, 1.766) and 1.346 (1.057, 1.715), respectively. In addition, exposure to high-level greenness might reduce the risks of developing diabetes [HR = 0.801 (0.687, 0.934)]. Weak evidence of the interaction effect of PM_2.5/solid fuel use and greenness on diabetes was found.

SIGNIFICANCE

Both PM_2.5 and solid fuel use were associated with the increasing incidence of diabetes. In addition, high-level greenness might be a beneficial environmental factor for reducing the risks of developing diabetes. All in all, our findings might provide valuable references for public health apartments to formulate very fruitful policies to reduce the burden of diabetes.

IMPACT STATEMENT

Both PM_2.5 and solid fuel use were associated with the increasing incidence of diabetes while high-level greenness was not, which might provide valuable references for public health apartments to make policies.

Atrial Fibrillation and Diabetes Mellitus: Dangerous Liaisons or Innocent Bystanders?

Atrial fibrillation (AF) is the most common arrhythmia in adults and diabetes mellitus (DM) is a major risk factor for cardiovascular diseases. However, the relationship between both pathologies has not been fully documented and new evidence supports the existence of direct and independent links. In the myocardium, a combination of structural, electrical, and autonomic remodeling may lead to AF. Importantly, patients with AF and DM showed more dramatic alterations than those with AF or DM alone, particularly in mitochondrial respiration and atrial remodeling, which alters conductivity, thrombogenesis, and contractile function. In AF and DM, elevations of cytosolic Ca²⁺ and accumulation of extra cellular matrix (ECM) proteins at the interstitium can promote delayed afterdepolarizations. The DM-associated low-grade inflammation and deposition/infiltration of epicardial adipose tissue (EAT) enforce abnormalities in Ca²⁺ handling and in excitation-contraction coupling, leading to atrial myopathy. This atrial enlargement and the reduction in passive emptying volume and fraction can be key for AF maintenance and re-entry. Moreover, the stored EAT can prolong action of potential durations and progression from paroxysmal to persistent AF. In this way, DM may increase the risk of thrombogenesis as a consequence of increased glycation and oxidation of fibrinogen and plasminogen, impairing plasmin conversion and resistance to fibrinolysis. Additionally, the DM-associated autonomic remodeling may also initiate AF and its re-entry. Finally, further evidence of DM influence on AF development and maintenance are based on the anti-arrhythmogenic effects of certain anti-diabetic drugs like SGLT2 inhibitors. Therefore, AF and DM may share molecular alterations related to Ca²⁺ mobility, mitochondrial function and ECM composition that induce atrial remodeling and defects in autonomic stimulation and conductivity. Likely, some specific therapies could work against the associated cardiac damage to AF and/or DM.

Multiple targets related to mitochondrial function unveiled by metabolomics and proteomics profiles of hearts from atrial fibrillation patients

Background: The prominent mitochondrial metabolic changes of the atrium reportedly have significant impact on electrical signals and structural remodeling which play important roles in the occurrence and development of atrial fibrillation (AF). However, the mechanism is not completely known.

Objective: This study was aimed to explore the mitochondrial metabolism reprogrammed in AF patients by integrating metabolomics as well as proteomics of human atrium tissues.

Methods and Results: Left atrial tissue samples were harvested from 10 non-valvular AF patients and 10 matched samples from healthy donors for transplantation. In metabolomics analysis, 113 metabolites were upregulated and 10 metabolites were downregulated in AF, where multiple pathways related to mitochondrial energy metabolism were enriched. Correlation analysis between the differentially expressed proteins and metabolites identified several hub proteins related to mitochondrial function including Glycerol-3-phosphate dehydrogenase 2 (GPD2), Synemin (SYNM), Plectin (PLEC), with MCC score of 27, 17, 16, respectively, which have the most interactions with the dysregulated metabolites and ranked at the top in network string interactions scored by MCC method. All 330 differentially expressed proteins including 225 upregulated and 105 downregulated molecules were revealed and analyzed, which identified the downregulation of GPD2 (p = 0.02 and FC = 0.77), PLEC (p < 0.001 and FC = 0.71) and SYNM (p = 0.04 and FC = 0.76) in AF patients. Gene Set Variation Analysis (GSEA) showed mitochondrial metabolism-associated pathways including oxidative phosphorylation (NES: −1.73) and ATP biosynthetic process (NES: −2.29), were dramatically diversified in human AF. In GSVA, the expression levels of GPD2, PLEC, and SYNM were demonstrated to be associated with multiple metabolic pathways related to mitochondrial function (e.g., lipid metabolism and AMP activated protein kinase signaling) and cardiac structural and electrical remodeling (e.g., contractile fiber, ion homeostasis), which were proven vital in the development and maintenance of AF.

Conclusion: In all, this study provides new insights into understanding the mechanisms of AF progression, especially the reprogramming mitochondrial metabolism, and identifies several genes related to mitochondrial function as novel targets for AF, which may be involved in the occurrence and development of AF.

Gene Polymorphism and Recurrent Atrial Fibrillation after Catheter Ablation: A Comprehensive Review

Atrial fibrillation (AF) is one of the most common cardiac arrhythmias, but its pathogenesis is still poorly understood. Catheter ablation is one of the most effective treatments for AF, but recurrence after ablation remains a challenge. There has been much research into the association of AF recurrence with several factors, including genetics. Over the past decade or so, significant advances have been made in the genetic architecture of atrial fibrillation. Genome-wide association studies (GWAS) have identified over 100 loci for genetic variants associated with atrial fibrillation. However, there is relatively little information on the systematic assessment of the genes related to AF recurrence after ablation. In this review article, we highlight the value of genetic polymorphisms in atrial fibrillation recurrence after catheter ablation and their potential mechanisms in the recurrence process to enhance our understanding of atrial fibrillation recurrence and contribute to individualized treatment strategies for patients with AF.

Intermittent fasting attenuates obesity-related atrial fibrillation via SIRT3-mediated insulin resistance mitigation

OBJECTIVE

Atrial fibrillation (AF) is the most common tachyarrhythmia in urgent need of therapeutic optimization. Obesity engenders AF, and its pathogenesis is closely intertwined with insulin resistance (IR), but mechanism-based management is still underinvestigated. Intermittent fasting (IF) is a novel lifestyle intervention that mitigates IR, a potential AF driver, yet whether IF can prevent obesity-related AF remains elusive. Here, we aimed to evaluate the impacts of short-term IF on AF and to uncover the underlying mechanism.

METHODS

We subjected obese mice (high-fat diet for 8-week) to IF (alternative-day fasting for another 5-week) for AF vulnerability and substrate formation assessment, and similarly treated neonatal atrial cardiomyocytes (NRCMs) and fibroblasts (NRCFs) (palmitate, 200 μM) with IF (alternative-day short-term starvation for 8-day) for mechanism investigation.

RESULTS

Obese mice were prone to AF and atrial remodeling. IF reduced AF inducibility, duration, and reversed atrial remodeling including channel disturbance, left atrial dilation, cardiac hypertrophy and fibrosis in obese mice independent of weight loss. Mechanistically, IF up-regulated the SIRT3 protein level both in vivo and in vitro, and pharmacologic inhibition (3-(1H-1,2,3-Triazol-4-yl) pyridine, 50 μM) and genetic suppression of SIRT3 could attenuate the IF-mediated benefits against hypertrophy and fibrosis. Furthermore, IF activated AMPK and Akt signaling, two positive downstream targets of SIRT3, and inactivated HIF1α signaling, a negative downstream target of SIRT3 in both obese mice atria and palmitate-treated cells, while inhibition of SIRT3 reversed these effects.

CONCLUSION

IF prevents obesity-related AF via SIRT3-mediated IR mitigation, thus representing a feasible lifestyle intervention to improve AF management.

Dysregulated carbohydrate and lipid metabolism and risk of atrial fibrillation in advanced old age

OBJECTIVE

Obesity and dysmetabolism are major risk factors for atrial fibrillation (AF). Fasting and postload levels of glucose and non-esterified fatty acids (NEFAs) reflect different facets of metabolic regulation. We sought to study their respective contributions to AF risk concurrently.

METHODS

We assessed levels of fasting and postload glucose and NEFA in the Cardiovascular Health Study to identify associations with AF incidence and, secondarily, with ECG parameters of AF risk available at baseline. Linear and Cox regressions were performed.

RESULTS

The study included 1876 participants (age 77.7±4.4). During the median follow-up of 11.4 years, 717 cases of incident AF occurred. After adjustment for potential confounders, postload glucose showed an association with incident AF (HR per SD increment of postload glucose=1.11, 95% CI 1.02 to 1.21, p=0.017). Both glucose measures, but not NEFA, were positively associated with higher P wave terminal force in V1 (PTFV1); the association remained significant only for postload glucose when the two measures were entered together (β per SD increment=138 μV·ms, 95% CI 15 to 260, p=0.028). Exploratory analyses showed significant interaction by sex for fasting NEFA (pinteraction=0.044) and postload glucose (pinteraction=0.015) relative to AF, with relationships stronger in women. For postload glucose, the association with incident AF was observed among women but not among men.

CONCLUSIONS

Among older adults, postload glucose was positively associated with incident AF, with consistent findings for PTFV1. In exploratory analyses, the relationship with AF appeared specific to women. These findings require further study but suggest that interventions to address postprandial dysglycaemia late in life might reduce AF.

STAT3 signaling promotes cardiac injury by upregulating NCOA4-mediated ferritinophagy and ferroptosis in high-fat-diet fed mice

High-fat diet (HFD) intake provokes obesity and cardiac anomalies. Recent studies have found that ferroptosis plays a role in HFD-induced cardiac injury, but the underlying mechanism is largely unclear. Ferritinophagy is an important part of ferroptosis that is regulated by nuclear receptor coactivator 4 (NCOA4). However, the relationship between ferritinophagy and HFD-induced cardiac damage has not been explored. In this study, we found that oleic acid/palmitic acid (OA/PA) increased the level of ferroptotic events including iron and ROS accumulation, upregulation of PTGS2 mRNA and protein levels, reduced SOD and GSH levels, and significant mitochondrial damage in H9C2 cells, which could be reversed by the ferroptosis inhibitor ferrostatin-1 (Fer-1). Intriguingly, we found that the autophagy inhibitor 3-methyladenine mitigated OA/PA-induced ferritin downregulation, iron overload and ferroptosis. OA/PA increased the protein level of NCOA4. Knockdown of NCOA4 by SiRNA partly reversed the reduction in ferritin, mitigated iron overload and lipid peroxidation, and subsequently alleviated OA/PA-induced cell death, indicating that NCOA4-mediated ferritinophagy was required for OA/PA-induced ferroptosis. Furthermore, we demonstrated that NCOA4 was regulated by IL-6/STAT3 signaling. Inhibition or knockdown of STAT3 effectively reduced NCOA4 levels to protect H9C2 cells from ferritinophagy-mediated ferroptosis, whereas STAT3 overexpression by plasmid appeared to increase NCOA4 expression and contribute to classical ferroptotic events. Consistently, phosphorylated STAT3 upregulation, ferritinophagy activation, and ferroptosis induction also occurred in HFD-fed mice and were responsible for HFD-induced cardiac injury. In addition, we found evidence that piperlongumine, a natural compound, effectively reduced phosphorylated STAT3 levels to protect cardiomyocytes from ferritinophagy-mediated ferroptosis both in vitro and in vivo. Based on these findings, we concluded that ferritinophagy-mediated ferroptosis was one of the critical mechanisms contributing to HFD-induced cardiac injury. The STAT3/NCOA4/FTH1 axis might be a novel therapeutic target for the treatment of HFD-induced cardiac injury.

Celastrol confers ferroptosis resistance via AKT/GSK3β signaling in high-fat diet-induced cardiac injury

Obesity-induced cardiac dysfunction is a severe global disease associated with high dietary fat intake, and its pathogenesis includes inflammation, oxidative stress, and ferroptosis. Celastrol (Cel) is a bioactive compound isolated from the herb Tripterygium wilfordii, which has a protective influence on cardiovascular diseases. In this study, the role of Cel in obesity-induced ferroptosis and cardiac injury was investigated. We found that Cel alleviated ferroptosis induced by Palmitic acid (PA), exhibiting a decrease in the LDH, CK-MB, Ptgs2, and Lipid Peroxidation levels. After cardiomyocytes were treated with additional LY294002 and LiCl, Cel exerted its protective effect through increased AKT/GSK3β phosphorylation and decreased level of lipid peroxidation and Mitochondrial ROS. The systolic left ventricle (LV) dysfunction of obese mice was alleviated via ferroptosis inhibition by elevated p-GSK3β and decreased Mitochondrial ROS under Cel treatment. Moreover, mitochondrial anomalies included swelling and distortion in the myocardium which was relieved with Cel. In conclusion, our results demonstrate that ferroptosis resistance with Cel under HFD conditions targets AKT/GSK3β signaling, which provides novel therapeutic strategies in obesity-induced cardiac injury.

The effect of curcumin-piperine on cardiometabolic, inflammatory and oxidative stress factors and macular vascular density in optical coherence tomography angiography (OCTA) in patients with non-proliferative diabetic retinopathy: Study protocol for a randomized, double-blind controlled trial

Objective

Curcumin is a safe phytochemical with antioxidant, anti-inflammatory, antidiabetic, and lipid-lowering effects. This study aims to investigate the efficacy of curcumin-piperine in non-proliferative diabetic retinopathy.

Materials and Methods

In this double-blind randomized trial, 60 diabetic retinopathy patients after meeting the inclusion criteria will be randomly assigned to two groups of curcumin-piperine supplementation (1000 mg per day for 12 weeks) or receiving placebo. The density of small blood vessels in the retina by optical coherence tomography angiography (OCTA), fasting blood glucose, triglyceride, renal indices (blood urea nitrogen and creatinine), high-sensitivity C-reactive protein, total antioxidant capacity, total oxidant status, body mass index, waist circumference, and weight will be measured.

Conclusion

If the beneficial effects of curcumin on diabetic retinopathy are observed, this safe, this natural and inexpensive herbal supplement can be considered a therapeutic solution in these patients.

Mitochondrial Dysfunction in Cardiac Arrhythmias

Electrophysiological and structural disruptions in cardiac arrhythmias are closely related to mitochondrial dysfunction. Mitochondria are an organelle generating ATP, thereby satisfying the energy demand of the incessant electrical activity in the heart. In arrhythmias, the homeostatic supply-demand relationship is impaired, which is often accompanied by progressive mitochondrial dysfunction leading to reduced ATP production and elevated reactive oxidative species generation. Furthermore, ion homeostasis, membrane excitability, and cardiac structure can be disrupted through pathological changes in gap junctions and inflammatory signaling, which results in impaired cardiac electrical homeostasis. Herein, we review the electrical and molecular mechanisms of cardiac arrhythmias, with a particular focus on mitochondrial dysfunction in ionic regulation and gap junction action. We provide an update on inherited and acquired mitochondrial dysfunction to explore the pathophysiology of different types of arrhythmias. In addition, we highlight the role of mitochondria in bradyarrhythmia, including sinus node dysfunction and atrioventricular node dysfunction. Finally, we discuss how confounding factors, such as aging, gut microbiome, cardiac reperfusion injury, and electrical stimulation, modulate mitochondrial function and cause tachyarrhythmia.

Prediabetes as a risk factor for new-onset atrial fibrillation: the propensity-score matching cohort analyzed using the Cox regression model coupled with the random survival forest

BACKGROUND

The glycemic continuum often indicates a gradual decline in insulin sensitivity leading to an increase in glucose levels. Although prediabetes is an established risk factor for both macrovascular and microvascular diseases, whether prediabetes is independently associated with the risk of developing atrial fibrillation (AF), particularly the occurrence time, has not been well studied using a high-quality research design in combination with statistical machine-learning algorithms.

METHODS

Using data available from electronic medical records collected from the National Taiwan University Hospital, a tertiary medical center in Taiwan, we conducted a retrospective cohort study consisting 174,835 adult patients between 2014 and 2019 to investigate the relationship between prediabetes and AF. To render patients with prediabetes as comparable to those with normal glucose test, a propensity-score matching design was used to select the matched pairs of two groups with a 1:1 ratio. The Kaplan-Meier method was used to compare the cumulative risk of AF between prediabetes and normal glucose test using log-rank test. The multivariable Cox regression model was employed to estimate adjusted hazard ratio (HR) for prediabetes versus normal glucose test by stratifying three levels of glycosylated hemoglobin (HbA1c). The machine-learning algorithm using the random survival forest (RSF) method was further used to identify the importance of clinical factors associated with AF in patients with prediabetes.

RESULTS

A sample of 14,309 pairs of patients with prediabetes and normal glucose test result were selected. The incidence of AF was 11.6 cases per 1000 person-years during a median follow-up period of 47.1 months. The Kaplan-Meier analysis revealed that the risk of AF was significantly higher in patients with prediabetes (log-rank p < 0.001). The multivariable Cox regression model indicated that prediabetes was independently associated with a significant increased risk of AF (HR 1.24, 95% confidence interval 1.11-1.39, p < 0.001), particularly for patients with HbA1c above 5.5%. The RSF method identified elevated N-terminal natriuretic peptide and altered left heart structure as the two most important risk factors for AF among patients with prediabetes.

CONCLUSIONS

Our study found that prediabetes is independently associated with a higher risk of AF. Furthermore, alterations in left heart structure make a significant contribution to this elevated risk, and these structural changes may begin during the prediabetes stage.

Empagliflozin suppresses mitochondrial reactive oxygen species generation and mitigates the inducibility of atrial fibrillation in diabetic rats

Introduction

Recent studies have demonstrated that sodium-glucose co-transporter-2 inhibitors (SGLT2-i) reduce the risk of atrial fibrillation (AF) in patients with diabetes mellitus (DM), in which oxidative stress due to increased reactive oxygen species (ROS) contributes to the pathogenesis of AF. We aimed to further investigate this, and examine whether the SGLT2-i empagliflozin suppresses mitochondrial-ROS generation and mitigates fibrosis.

Methods

A high-fat diet and low-dose streptozotocin treatment were used to induce type-2 DM (T2DM) in Sprague-Dawley rats. The rats were randomly divided into three groups: control, DM, and DM treated with empagliflozin (30 mg/kg/day) for 8 weeks. The mitochondrial respiratory capacity and ROS generation in the atrial myocardium were measured using a high-resolution respirometer. Oxidative stress markers and protein expression related to mitochondrial biogenesis and dynamics as well as the mitochondrial morphology were examined in the atrial tissue. Additionally, mitochondrial function was examined in H9c2 cardiomyoblasts. Atrial tachyarrhythmia (ATA) inducibility, interatrial conduction time (IACT), and fibrosis were also measured.

Results

Inducibility of ATA, fibrosis, and IACT were increased in rats with DM when compared to controls, all of which were restored by empagliflozin treatment. In addition, the rats with DM had increased mitochondrial-ROS with an impaired complex I-linked oxidative phosphorylation capacity. Importantly, empagliflozin seemed to ameliorate these impairments in mitochondrial function. Furthermore, empagliflozin reversed the decrease in phosphorylated AMPK expression and altered protein levels related to mitochondrial biogenesis and dynamics, and increased mitochondrial content. Empagliflozin also improved mitochondrial function in H9c2 cells cultured with high glucose medium.

Discussion

These data suggest that empagliflozin has a cardioprotective effect, at least in part, by reducing mitochondrial ROS generation through AMPK signaling pathways in the atrium of diabetic rats. This suggests that empagliflozin might suppress the development of AF in T2DM.

L, E. E, Qi R, Mu X, Feng L, Ba G, Li Y, Zhang J, Bai L, Fu M. Metabolomics analysis reveals amelioration effects of yellowhorn tea extract on hyperlipidemia, inflammation, and oxidative stress in high-fat diet-fed mice

Yellowhorn tea (YT) is traditionally used as a lipid-lowering beverage in Mongolian minorities. However, the pharmacological effects of YT extract and its specific metabolic changes in hyperlipidemia models are not fully understood. The aim of this study was to identify biomarkers using untargeted metabolomics techniques and to investigate the mechanisms underlying the changes in metabolic pathways associated with lipid lowering, anti-inflammation and anti-oxidant in hyperlipidemic mice. A high-fat diet (HFD)-induced hyperlipidemic mouse model was established. YT extract was administered as oral gavage at 0.15, 0.3, and 0.6 g/kg doses for 10 weeks. HFD-induced hyperlipidemia and the therapeutic effect of YT extract were evaluated based on histopathology and by assessing blood lipid levels. Liver inflammatory factors and oxidative stress indices were determined using enzyme-linked immunosorbent assays. Liver metabolites were evaluated using untargeted metabolomics. Biochemical and histological examinations showed that YT extract significantly reduced body-weight gain (p < 0.01) and fat deposition in tissues. YT extract significantly reduced the levels of serum and liver triglyceride and total cholesterol; inflammatory factors [interleukin (IL)-6, IL-1β, and tumor necrosis factor-α]; malondialdehyde; and leptin (p < 0.05) in hyperlipidemic mice. YT extract also significantly increased the levels of oxidative stress indicators (superoxide dismutase, catalase, and glutathione peroxidase) and adiponectin. Metabolomics studies revealed several endogenous molecules were altered by the high-fat diet and recovery following intervention with YT extract. The metabolites that were significantly different in the liver after YT intake included citicoline, acetylcholine, pyridoxine, and NAD. Pathway analysis indicated that YT extract ameliorated HFD-induced hyperlipidemia in mice via three major metabolic pathways, namely, glycerophospholipid metabolism, vitamin B6 metabolism, and nicotinate and nicotinamide metabolism. This study demonstrates YT extract has profound effects on the alleviation of HFD-induced hyperlipidemia, inflammation and oxidative stress.

Identification and Verification of Biomarkers and Immune Infiltration in Obesity-Related Atrial Fibrillation

Obesity is an independent risk factor for atrial fibrillation (AF). However, the mechanisms underlying this crosstalk are still being uncovered. Co-differentially expressed genes (co-DEGs) of AF and obesity microarrays were identified by bioinformatics analysis. Subsequently, functional enrichment, cell-type enrichment, and protein-protein interaction network analyses of co-DEGs were carried out. Then, we validated the hub genes by qRT-PCR of patients' blood samples. Finally, CIBERSORT was utilized to evaluate the AF microarray to determine immune infiltration and the correlation between validated hub genes and immune cells. A total of 23 co-up-regulated DEGs in AF and obesity microarrays were identified, and these genes were enriched in inflammation- and immune-related function. The enriched cells were whole blood, CD33+ myeloid, and CD14+ monocytes. The hub genes were identified as MNDA, CYBB, CD86, FCGR2C, NCF2, LCP2, TLR8, HLA-DRA, LCP1, and PTPN22. All hub genes were only elevated in blood samples of obese-AF patients. The CIBERSORT analysis revealed that the AF patients' left atrial appendage had increased infiltration of naïve B cells and decreased infiltration of memory B cells. The hub genes were related positively to naïve B cells and negatively to memory B cells. Ten hub genes may serve as biomarkers for obesity-related AF. These findings may also aid in comprehending pathophysiological mechanisms for obesity-related AF.

Monotropein attenuates doxorubicin-induced oxidative stress, inflammation, and arrhythmia via the AKT signal pathway

As a glycoside iridoid, monotropein (MON) has a wide range of pharmacological properties, including anti-inflammatory, antioxidant, and anti-apoptotic effects. However, few studies have investigated MON's cardiovascular protective effects. Therefore, this study aimed to explore the role of MON in doxorubicin (DOX)-induced cardiotoxicity. To establish the myocardial toxicity model, mice were intraperitoneally injected with DOX. After admimistration of DOX, myocardial injury markers were increased, cardiac function was reduced, and pathological changes were observed in the myocardium, indicating successful construction of the myocardial injury model. Our study showed that MON treatment mitigated DOX-induced myocardial damage and improved cardiac dysfunction. In addition, DOX-treated mice displayed higher levels of inflammation and oxidative stress, while MON treatment also reversed these pathological changes. Moreover, DOX-treated mice were more susceptible to ventricular fibrillation, whereas MON reduced ventricular fibrillation incidence. Further studies have shown that MON could reverse DOX-induced inhibition of the AKT signaling pathway. Besides, the application of AKT inhibitor could partially abolish MON's cardioprotective effects. To conclude, this study demonstrated the ability of MON to reduce DOX-induced myocardial damage, cardiac dysfunction, inflammation, and oxidative stress, as well as ventricular fibrillation risk. These may attributable to the activation of the AKT pathway.

A bibliometric and visual analysis of low carbohydrate diet

Introduction

Numerous studies have confirmed the effects of low carbohydrate diet (LChD) on metabolism and chronic diseases. However, there were no bibliometric studies on LChD. This study was conducted through a bibliometric analysis to investigate the current status, hotspots and frontiers trends.

Methods

We searched all research publications related to LChD from 2002 to 2021 on the Web of Scientific Core Collection (WoSCC). CiteSpace and VOSviewer software was used to analyze countries/regions, institutions, journals, authors, references, and keywords.

Results

A total of 6938 papers were included, with an increasing trend of annual publication. LChD categories mainly included nutrition, endocrinology, and neurosciences which reflected the interdisciplinary characteristics. USA was with the largest number and the world science center in LChD field. Universities were main research institutions and five of the top 10 institutions were from USA. Eric Heath Kossoff had 101 publications and ranked first. Nutrients was the leading journal. "A randomized trial of a low-carbohydrate diet for obesity" and "Obesity" were considered to be the most co-cited and cited reference respectively. The hotspots of LChD are four aspects, "ketogenic diet", "metabolism disease", "cardiovascular disease" and "cancer". We summarized that "oxidative stress", "gut microbiota", and "inflammation factors" are becoming frontiers trends of LChD research in the future and deserve further study.

Discussion

Over the past 20 years research on LChD has gained great attention. To better explore LChD field, multilevel mechanism studies will be required in the future.

ROCK (RhoA/Rho Kinase) Activation in Atrial Fibrillation: Molecular Pathways and Clinical Implications

Among the complex mechanisms of AF pathogenesis, intracellular calcium overload and oxidative stress play a major role, both triggered by inflammatory processes. The additional basic event taking place in AF is atrial fibrotic remodeling, again triggered by oxidative stress, which is determined by connexins rearrangement and differentiation of fibroblasts into active collagensecreting myofibroblasts. RhoA/ROCK system is the final pathway of a wide spectrum of molecular effectors such as Angiotensin II, platelet-derived growth factor, connective tissue growth factor and transforming growth factor β, that overall determine calcium dysregulation and pro-fibrotic remodeling. Both in experimental and clinical studies, RhoA/ROCK activation has been linked to superoxide ion production, fibrotic remodeling and connexins rearrangement, with important consequences for AF pathogenesis. ROCK pathway inhibition may therefore be a therapeutic or preventive target for special AF subgroups of patients.

The Role of NLRP3 Inflammasome Signaling on Arrhythmias in Diabetes

Diabetes is a significant risk factor for arrhythmias. However, the pathophysiology of diabetes-related arrhythmias still needs to be elucidated, presumably associated with structural and electrical remodeling. There is growing evidence that inflammation and arrhythmias are intimately associated, which has spurred significant interest in exploring the regulatory links in diabetes. Recent research findings have revealed a vital role for the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome signaling, and facilitated the occurrence of arrhythmias in diabetes, including NLRP3 inflammasome activation by multiple stressors and its downstream cytokines, interleukin-1β (IL-1β) and interleukin-18 (IL-18). This narrative review aims to summarize the complex interaction between NLRP3 inflammasomes signaling and diabetes-related arrhythmias. Articles regarding the role of NLRP3 inflammasome in diabetes-related arrhythmias and relevant mechanisms were selected. Relevant articles were selected from PubMed. The search terms were "NLRP3 inflammasome" and "diabetes" and "arrhythmia". Important references from selected articles were also retrieved. The role of NLRP3 inflammasome signaling in diabetes-induced arrhythmias may provide a new option for the prevention and treatment diabetes-related arrhythmias.

Association of glucagon-like peptide-1 receptor agonists with cardiac arrhythmias in patients with type 2 diabetes or obesity: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have been highly recommended for glycemic control and weight reduction. However, evidence has accumulated that GLP-1 RAs treatment is related to an increase in heart rate, which could potentially induce cardiac arrhythmias. This study aims to investigate the association of GLP-1 RAs therapy with incident arrhythmias in diabetic and obese patients.

METHODS

MEDLINE, EMBASE, Cochrane Library, and ClinicalTrials.gov were systematically searched from inception up to May 25, 2022. Randomized controlled trials (RCTs) comparing GLP-1 RAs with placebo or active control for adults with type 2 diabetes or obesity were included. The outcomes of interest were prespecified as incident atrial fibrillation (AF), atrial flutter (AFL), ventricular arrhythmias (VAs), and sudden cardiac death (SCD). Mantel-Haenszel relative risk (MH-RR) with a corresponding 95% confidence interval (95% CI) was estimated using a fixed-effects model.

RESULTS

A total of 56 RCTs involving 79,720 participants (44,028 GLP-1 RAs vs 35,692 control: mean age 57.3 years) were included from 7692 citations. GLP-1 RAs use overall did not significantly increase the risk of AF (RR 0.97, 95% CI 0.83-1.12), AFL (RR 0.83, 95% CI 0.59-1.17), VAs (RR 1.24, 95% CI 0.92-1.67), and SCD (RR 0.89, 95% CI 0.67-1.19), compared with controls. In further subgroup analyses, we observed an increasing trend toward incident AF with dulaglutide (RR 1.40, 95% CI 1.03-1.90) while an inverse trend with oral semaglutide (RR 0.43, 95% CI 0.21-0.87). Additionally, higher doses of GLP-1 RAs (RR 1.63, 95% CI 1.11-2.40) and higher baseline BMI (RR 1.60, 95% CI 1.04-2.48) might significantly increase the risk of VAs. No significant differences were identified in other subgroup analyses.

CONCLUSIONS

GLP-1 RAs therapy was not associated with an overall higher risk of arrhythmias, demonstrating an assuring cardiovascular safety profile. Further studies are required to determine whether the potential antiarrhythmic or arrhythmogenic effect of GLP-1 RAs is drug-specific and varies from doses or baseline BMI.

TRIAL REGISTRATION

PROSPERO Identifier: CRD42022339389.

Alarmins as a Possible Target of Future Therapies for Atrial Fibrillation

To date, worldwide, atrial fibrillation is the most common cardiovascular disease in adults, with a prevalence of 2% to 4%. The trigger of the pathophysiological mechanism of arrhythmia includes several factors that sustain and exacerbate the disease. Ectopic electrical conductivity, associated with the resulting atrial mechanical dysfunction, atrial remodeling, and fibrosis, promotes hypo-contractility and blood stasis, involving micro endothelial damage. This causes a significant local inflammatory reaction that feeds and sustains the arrhythmia. In our literature review, we evaluate the role of HMGB1 proteins, heat shock proteins, and S100 in the pathophysiology of atrial fibrillation, offering suggestions for possible new therapeutic strategies. We selected scientific publications on the specific topics "alarmins" and "atrial fibrillation" from PubMed. The nonsystematic review confirms the pivotal role of molecules such as S100 proteins, high-mobility group box-1, and heat shock proteins in the molecular pattern of atrial fibrillation. These results could be considered for new therapeutic opportunities, including inhibition of oxidative stress, evaluation of new anticoagulant drugs with novel therapeutic targets, molecular and genetic studies, and consideration of these alarmins as predictive or prognostic biomarkers of disease onset and severity.

Garlic (Allium sativum L.) in diabetes and its complications: Recent advances in mechanisms of action

Diabetes mellitus (DM) is a metabolic disease characterized by chronic hyperglycemia and impaired islet secretion that places a heavy burden on the global health care system due to its high incidence rate, long disease course and many complications. Fortunately, garlic (Allium sativum L.), a well-known medicinal plant and functional food without the toxicity and side effects of conventional drugs, has shown positive effects in the treatment of diabetes and its complications. With interdisciplinary development and in-depth exploration, we offer a clear and comprehensive summary of the research from the past ten years, focusing on the mechanisms and development processes of garlic in the treatment of diabetes and its complications, aiming to provide a new perspective for the treatment of diabetes and promote the efficient development of this field.

Effect of Sitagliptin Versus Glibenclamide on Glycemic Markers, Lipid Profile Inflammatory and Oxidative Stress Factors in Type 2 Diabetes Patients: a Double-Blinded Randomized Controlled Trial

Objectives:Diabetes mellitus is leading to chronic complications, including cardiovascular diseases. The aim of this study was to compare the effect of Sitagliptin and Glibenclamide on glycemic markers, lipid profile inflammatory, and oxidative stress factors in type 2 diabetes patients. Methods: This double-blinded randomized controlled trial was performed on patients with type 2 diabetes mellitus (n=54). The treatment group (27 patients) received 100 mg of Sitagliptin once daily + 500 mg Metformin twice daily, orally, for 12 weeks, and the control group (27 patients) was given 5 mg of Glibenclamide once daily + 500 mg Metformin twice daily, also orally, for 12 weeks. Serum levels of tumor necrosis factor alpha (TNF-α), high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), lipid profile [cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), triglyceride (TG)], fasting blood sugar (FBS) and hemoglobin A1C (HbA1c), body weight, and body mass index (BMI) were measured before and after the study. Results:In both groups, the FBS level was significantly reduced from baseline (P=0.03 in the Sitagliptin group and P=0.02 in the Glibenclamide one). The percent of HbA1c was also significantly reduced from baseline in both the Sitagliptin group (P=0.01) and the Glibenclamide one (P=0.008). However, comparing the groups, these changes were not different. In the Sitagliptin group, IL-6 was significantly reduced from baseline (P=0.01) as well as in comparison with the Glibenclamide group (P=0.001). The TG level was significantly lower than the baseline in the Sitagliptin group (P=0.03), so changes between groups were significant (P=0.04). Weight and BMI were significantly increased from baseline in the Glibenclamide group (P=0.02 and P=0.03, respectively), and their changes between the two groups were also significant (P=0.001). Conclusion:These finding support the favorable effects of Sitagliptin on cardiovascular risks beyond its advantages on insulin-glucose hemostasis in patients with type 2 diabetes.

The Impact of Sleep Disturbance on Gut Microbiota, Atrial Substrate, and Atrial Fibrillation Inducibility in Mice: A Multi-Omics Analysis

This study examined the effect of sleep disturbance on gut microbiota (GM), atrial substrate, and atrial fibrillation (AF) inducibility. C57BL/6 mice were subjected to six weeks of sleep deprivation (SD) using the method of modified multiple-platform. Transesophageal burst pacing was performed to evaluate AF inducibility. Feces, plasma, and an atrium were collected and analyzed by 16s rRNA sequencing, liquid chromatography−mass spectrometry (LC-MS)-based metabolome, histological studies, and transcriptome. Higher AF inducibility (2/30 of control vs. 15/30 of SD, p = 0.001) and longer AF duration (p < 0.001), concomitant with aggravated fibrosis, collagen, and lipid accumulation, were seen in the SD mice compared to control mice. Meanwhile, elevated alpha diversity, higher abundance of Flavonifractor, Ruminococcus, and Alloprevotella, as well as imbalanced functional pathways, were observed in the gut of SD mice. Moreover, the global patterns for the plasma metabolome were altered, e.g., the decreased butanoate metabolism intermediates in SD mice. In addition, disrupted metabolic homeostasis in the SD atrium, such as fatty acid metabolism, was analyzed by the transcriptome. These results demonstrated that the crosstalk between GM and atrial metabolism might be a promising target for SD-mediated AF susceptibility.

Impact of Dysfunctional Adipose Tissue Depots on the Cardiovascular System

Obesity with its associated complications represents a social, economic and health problem of utmost importance worldwide. Specifically, obese patients carry a significantly higher risk of developing cardiovascular disease compared to nonobese individuals. Multiple molecular mechanisms contribute to the impaired biological activity of the distinct adipose tissue depots in obesity, including secretion of proinflammatory mediators and reactive oxygen species, ultimately leading to an unfavorable impact on the cardiovascular system. This review summarizes data relating to the contribution of the main adipose tissue depots, including both remote (i.e., intra-abdominal, hepatic, skeletal, pancreatic, renal, and mesenteric adipose fat), and cardiac (i.e., the epicardial fat) adipose locations, on the cardiovascular system. Finally, we discuss both pharmacological and non-pharmacological strategies aimed at reducing cardiovascular risk through acting on adipose tissues, with particular attention to the epicardial fat.

Impact of mental disorders on the risk of atrial fibrillation in patients with diabetes mellitus: a nationwide population-based study

BACKGROUND

It is unclear whether mental disorders are an independent risk factor for atrial fibrillation (AF) in patients with diabetes. We aimed to investigate whether patients with diabetes who have mental disorders have an increased risk for AF.

METHODS

Using the Korea National Health Insurance Service database, we enrolled 2,512,690 patients diagnosed with diabetes without AF between 2009 and 2012. We assessed five mental disorders: depression, insomnia, anxiety, bipolar disorder, and schizophrenia. Newly diagnosed AF was identified during the follow-up period, and multivariate Cox regression analysis was performed.

RESULTS

Among the 2,512,690 patients (mean age 57.2 ± 12.3 years; 60.1% men), 828,929 (33.0%) had mental disorders. Among the five mental disorders, anxiety (68.1%) was the most common, followed by insomnia (40.0%). During a median follow-up duration of 7.1 years, new-onset AF was diagnosed in 79,525 patients (4.66 per 1,000 person-years). Patients with diabetes who had mental disorders showed a higher risk for AF (adjusted hazard ratio [HR] 1.19; 95% confidence interval [CI] 1.17-1.21; p-value < 0.001). Depression, insomnia, and anxiety were significantly associated with higher risk for AF (adjusted HR [95% CI]: 1.15 [1.12-1.17], 1.15 [1.13-1.18], and 1.19 [1.67-1.21], respectively; all p-values < 0.001), whereas bipolar disorder and schizophrenia were not.

CONCLUSIONS

Mental disorders, especially depression, insomnia, and anxiety, were associated with an increased risk for AF in patients with diabetes. Greater awareness with a prompt diagnosis of AF should be considered for patients with both DM and mental disorders.

Stress hyperglycemia ratio and neutrophil to lymphocyte ratio are reliable predictors of new-onset atrial fibrillation in patients with acute myocardial infarction

Background

The occurrence of new-onset atrial fibrillation (NOAF) post-acute myocardial infarction (AMI) is associated with worse outcomes. In this study, we sought to assess the predictive effect of stress hyperglycemia ratio (SHR) and neutrophil to lymphocyte ratio (NLR) to predict NOAF in patients with AMI.

Materials and methods

We recruited 3,194 individuals with AMI but free of atrial fibrillation (AF). AMI cases were stratified into groups according to SHR and NLR quartiles and were further categorized based on diabetes status. High SHR and high NLR were defined as the highest quartile of SHR and NLR. A nomogram incorporating risk factors for NOAF was constructed using multivariate logistic regression analyses. The performance of the novel nomogram was tested for predictive performance, agreement between the actual and predicted probability, and clinical utility using area under the curve (AUC), bootstrapped calibration curves, and decision curve analysis, respectively.

Result

A total of 245 (7.67%) patients developed NOAF post-AMI. The NOAF cases had higher values of SHR and NLR than non-NOAF patients after AMI regardless of diabetes status. After adjusting for potential confounders, high SHR and NLR were independently associated with NOAF post-AMI. Moreover, the novel nomogram incorporating high NLR and high SHR for NOAF risk estimation in patients with AMI showed satisfactory performance assessed by the AUC, calibration curves, decision curve analysis.

Conclusion

SHR and NLR were independently associated with NOAF in AMI patients. The constructed novel nomogram that incorporates SHR and NLR might assist in NOAF risk stratification post-AMI.

New insights into the characteristics of DRAK2 and its role in apoptosis: From molecular mechanisms to clinically applied potential

As a member of the death-associated protein kinase (DAPK) family, DAP kinase-associated apoptosis-inducing kinase 2 (DRAK2) performs apoptosis-related functions. Compelling evidence suggests that DRAK2 is involved in regulating the activation of T lymphocytes as well as pancreatic β-cell apoptosis in type I diabetes. In addition, DRAK2 has been shown to be involved in the development of related tumor and non-tumor diseases through a variety of mechanisms, including exacerbation of alcoholic fatty liver disease (NAFLD) through SRSF6-associated RNA selective splicing mechanism, regulation of chronic lymphocytic leukemia and acute myeloid leukemia, and progression of colorectal cancer. This review focuses on the structure, function, and upstream pathways of DRAK2 and discusses the potential and challenges associated with the clinical application of DRAK2-based small-molecule inhibitors, with the aim of advancing DRAK2 research.

Carbon Source Influences Antioxidant, Antiglycemic, and Antilipidemic Activities of Haloferax mediterranei Carotenoid Extracts

Haloarchaeal carotenoids have attracted attention lately due to their potential antioxidant activity. This work studies the effect of different concentrations of carbon sources on cell growth and carotenoid production. Carotenoid extract composition was characterized by HPLC-MS. Antioxidant activity of carotenoid extracts obtained from cell cultures grown under different nutritional conditions was determined by 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH), Ferric Reducing Ability Power (FRAP) and β-carotene bleaching assays. The ability of these carotenoid extracts to inhibit α-glucosidase, α-amylase, and lipase enzymes was also assessed to determine if they could be used to reduce blood glucose and lipid absorption. The maximum production of carotenoids (92.2 µg/mL) was observed combining 12.5% inorganic salts and 2.5% of glucose/starch. Antioxidant, hypoglycemic, and antilipidemic studies showed that higher carbon availability in the culture media leads to changes in the extract composition, resulting in more active haloarchaeal carotenoid extracts. Carotenoid extracts obtained from high-carbon-availability cell cultures presented higher proportions of all-trans-bacterioruberin, 5-cis-bacterioruberin, and a double isomeric bacterioruberin, whereas the presence 9-cis-bacterioruberin and 13-cis-bacterioruberin decreased. The production of haloarchaeal carotenoids can be successfully optimized by changing nutritional conditions. Furthermore, carotenoid composition can be altered by modifying carbon source concentration. These natural compounds are very promising in food and nutraceutical industries.

Incidence and Determinants of Spontaneous Cardioversion of Early Onset Symptomatic Atrial Fibrillation

Atrial fibrillation (AF) is the most frequent chronic arrhythmia worldwide, and it is associated with significant morbidity and mortality, making it a considerable burden both to patients and the healthcare system. Nowadays, an early attempt to restore sinus rhythm in acute symptomatic AF through electrical or pharmacological cardioversion is the most common approach in the Emergency Department (ED). However, considering the high percentage of spontaneous cardioversion of paroxysmal AF reported by many studies, this approach may not be the ideal choice for all patients. In this manuscript we performed a review of the most relevant studies found in literature with the aim of identifying the main determinants of spontaneous cardioversion, focusing on those easy to detect in the ED. We have found that the most relevant predictors of spontaneous cardioversion are the absence of Heart Failure (HF), a small atrial size, recent-onset AF, rapid Atrial Fibrillatory Rate and the relationship between a previous AF episode and Heart Rate/Blood Pressure. A number of those are utilized, along with other easily determined parameters, in the recently developed "ReSinus" score which predicts the likelihood of AF spontaneous cardioversion. Such identification may help the physician decide whether immediate cardioversion is necessary, or whether to adopt a "watch-and-wait" strategy in the presence of spontaneous cardioversion determinants.

Serum Lipopolysaccharide Is Associated with the Recurrence of Atrial Fibrillation after Radiofrequency Ablation by Increasing Systemic Inflammation and Atrial Fibrosis

Objectives

The gut microbiota and its metabolites are linked to inflammation and contribute to the progression of atrial fibrillation (AF), but the predictive value of the gut microbiota-derived metabolite lipopolysaccharide (LPS) for AF recurrence (RAF) is unknown. This study is aimed at investigating (1) the correlation between LPS and RAF and (2) its relationship with inflammation and atrial fibrosis.

Method

We performed a single-centre retrospective analysis in 159 AF patients. Fasting plasma samples were collected, and an enzyme-linked immunosorbent assay was used to determine the levels of serum LPS, interleukin-6 (IL-6), collagen type-1 C-terminal telopeptide (CITP), and transforming growth factor-β1 (TGFβ1). The cumulative risk for RAF was evaluated with Kaplan–Meier analysis. Cox proportional hazard analysis was carried out to predict the hazard of RAF. The correlations among LPS and IL-6, CITP, TGFβ1, and left atrial diameter (LAD) were analysed by Pearson's correlation coefficient. Subsequent univariate and multivariable linear regression analyses were carried out to evaluate the connection between clinical variables and Log-LPS.

Results

All 159 AF patients were included in this study. The proportion of persistent atrial fibrillation was 40.3%, the mean age was 61.9 ± 10.1 years, the proportion of males was 61.6%, and the mean LPS was 56.5 ± 29.5 pg/mL. After all patients were divided into tertiles according to the circulating LPS level, a total of 44 RAF occurred: 10 in the first tertile, 15 in the second tertile, and 19 in the third tertile (log-rank test P = 0.037). Heart failure (hazard ratio 2.029, P = 0.041), LAD (hazard ratio 1.064, P = 0.022), Log-LPS (hazard ratio 5.686, P = 0.043), and CITP (hazard ratio 6.841, P = 0.033) independently predicted the risk of RAF. In all patients, univariate analysis showed that heart failure, LAD, hs-CRP, IL-6, CITP, and TGF-β1 were connected with Log-LPS. Multivariate linear regression analysis indicated that IL-6 and hs-CRP were independently and positively connected with Log-LPS.

Conclusions

Our results indicated that circulating LPS was a predictor of RAF and may contribute to RAF incidence after ablation by increasing systemic inflammation and atrial fibrosis.

Cardiac-specific knockdown of Bhlhe40 attenuates angiotensin II (Ang II)-Induced atrial fibrillation in mice

Atrial fibrosis and atrial inflammation are associated with the pathogenesis of atrial fibrillation (AF). Basic helix–loop–helix family member E40 (Bhlhe40) is an important transcription factor, which is involved in tumors, inflammation, apoptosis, viral infection, and hypoxia. However, its role and molecular mechanism in AF remain unclear. In this study, a mouse model of AF was induced by Ang II infusion. The atrial diameter was evaluated using echocardiography. Induction and duration of AF were measured by programmed electrical stimulation. Atrial structural remodeling was detected using routine histologic examinations. Our results showed that Bhlhe40 was significantly upregulated in angiotensin II (Ang II)-stimulated atrial cardiomyocytes and atrial tissues and in tissues from patients with AF. Cardiac-specific knockdown of Bhlhe40 in mice by a type 9 recombinant adeno-associated virus (rAAV9)-shBhlhe40 significantly ameliorated Ang II-induced atrial dilatation, atrial fibrosis, and atrial inflammation, as well as the inducibility and duration of AF. Mechanistically, cardiac-specific knockdown of Bhlhe40 attenuated Ang II-induced activation of NF-κB/NLRP3, TGF-1β/Smad2 signals, the increased expression of CX43, and the decreased expression of Kv4.3 in the atria. This is the first study to suggest that Bhlhe40 is a novel regulator of AF progression, and identifying Bhlhe40 may be a new therapeutic target for hypertrophic remodeling and heart failure.

Dietary Intake, Nutritional Adequacy, and Food Sources of Selected Antioxidant Minerals and Vitamins; and Their Relationship with Personal and Family Factors in Spanish Children Aged 1 to <10 Years: Results from the EsNuPI Study

Minerals and vitamins involved in the antioxidant defense system are essential for healthy growth and proper development during infancy. Milk and dairy products are of particular importance for improving the supply of these nutrients to children. Indeed, the present study aimed to evaluate the nutrient intake and food sources of zinc (Zn), selenium (Se), retinol and carotenoids (sources of vitamin A), and vitamins C and E, and to analyze their relationships with personal and familiar factors in Spanish children from the EsNuPI study. One subpopulation representative of the Spanish population from 1 to <10 years old (n = 707) (reference group, REF) who reported consuming all types of milk over the last year, and another subpopulation of the same age who reported consuming fortified milk formulas (FMFs) (including follow-on formula, young child formula, growing up milk, toddler’s milk, and enriched and fortified milk) (n = 741) (fortified milk consumers, FMCs) completed two 24 h dietary recalls used to estimate their nutrient intakes and to compare them to the European Food Safety Authority (EFSA) Dietary Reference Values (DRVs). The REF reported higher median intakes than FMCs for Se (61 µg/kg vs. 51 µg/kg) and carotenoids (1079 µg/day vs. 998 µg/day). Oppositely, FMCs reported higher intakes than REF for Zn (7.9 mg/day vs. 6.9 mg/day), vitamin A (636 µg/day vs. 481 µg/day), vitamin E (8.9 mg/day vs. 4.5 mg/day), vitamin C (113 mg/day vs. 71 mg/day), and retinol (376 µg/day vs. 233 µg/day). In the REF group, more than 50% of the children met the EFSA recommendations for Zn (79.6%), Se (87.1%), vitamin A (71.3%), and vitamin C (96.7%), respectively. On the other hand, 92.2% were below the EFSA recommendations for vitamin E. In the FMC group, more than 50% of the children met the EFSA recommendations for Zn (55.2%), Se (90.8%), vitamin A (75.7%), vitamin E (66.7%), and vitamin C (100%). We found statistically significant differences between subpopulations for all cases except for Se. In both subpopulations, the main sources of all antioxidant nutrients were milk and dairy products. For carotenoids, the main sources were vegetables and fruits followed by milk and dairy products. A high percentage of children had vitamins A and E intakes below the recommendations, information of great importance to stakeholders. More studies using intakes and biomarkers are needed, however, to determine an association with diverse factors of oxidative damage.

LncRNAs regulate ferroptosis to affect diabetes and its complications

Worldwide, the rapid increase in the incidence of diabetes and its complications poses a serious threat to human health. Ferroptosis, which is a new nonapoptotic form of cell death, has been proven to be closely related to the occurrence and development of diabetes and its complications. In recent years, lncRNAs have been confirmed to be involved in the occurrence and development of diabetes and play an important role in regulating ferroptosis. An increasing number of studies have shown that lncRNAs can affect the occurrence and development of diabetes and its complications by regulating ferroptosis. Therefore, lncRNAs have great potential as therapeutic targets for regulating ferroptosis-mediated diabetes and its complications. This paper reviewed the potential impact and regulatory mechanism of ferroptosis on diabetes and its complications, focusing on the effects of lncRNAs on the occurrence and development of ferroptosis-mediated diabetes and its complications and the regulation of ferroptosis-inducing reactive oxygen species, the key ferroptosis regulator Nrf2 and the NF-κB signaling pathway to provide new therapeutic strategies for the development of lncRNA-regulated ferroptosis-targeted drugs to treat diabetes.

The Complex Relation between Atrial Cardiomyopathy and Thrombogenesis

Heart disease, as well as systemic metabolic alterations, can leave a ‘fingerprint’ of structural and functional changes in the atrial myocardium, leading to the onset of atrial cardiomyopathy. As demonstrated in various animal models, some of these changes, such as fibrosis, cardiomyocyte hypertrophy and fatty infiltration, can increase vulnerability to atrial fibrillation (AF), the most relevant manifestation of atrial cardiomyopathy in clinical practice. Atrial cardiomyopathy accompanying AF is associated with thromboembolic events, such as stroke. The interaction between AF and stroke appears to be far more complicated than initially believed. AF and stroke share many risk factors whose underlying pathological processes can reinforce the development and progression of both cardiovascular conditions. In this review, we summarize the main mechanisms by which atrial cardiomyopathy, preceding AF, supports thrombogenic events within the atrial cavity and myocardial interstitial space. Moreover, we report the pleiotropic effects of activated coagulation factors on atrial remodeling, which may aggravate atrial cardiomyopathy. Finally, we address the complex association between AF and stroke, which can be explained by a multidirectional causal relation between atrial cardiomyopathy and hypercoagulability.

Profile of crosstalk between glucose and lipid metabolic disturbance and diabetic cardiomyopathy: Inflammation and oxidative stress

In recent years, the risk, such as hypertension, obesity and diabetes mellitus, of cardiovascular diseases has been increasing explosively with the development of living conditions and the expansion of social psychological pressure. The disturbance of glucose and lipid metabolism contributes to both collapse of myocardial structure and cardiac dysfunction, which ultimately leads to diabetic cardiomyopathy. The pathogenesis of diabetic cardiomyopathy is multifactorial, including inflammatory cascade activation, oxidative/nitrative stress, and the following impaired Ca2+ handling induced by insulin resistance/hyperinsulinemia, hyperglycemia, hyperlipidemia in diabetes. Some key alterations of cellular signaling network, such as translocation of CD36 to sarcolemma, activation of NLRP3 inflammasome, up-regulation of AGE/RAGE system, and disequilibrium of micro-RNA, mediate diabetic oxidative stress/inflammation related myocardial remodeling and ventricular dysfunction in the context of glucose and lipid metabolic disturbance. Here, we summarized the detailed oxidative stress/inflammation network by which the abnormality of glucose and lipid metabolism facilitates diabetic cardiomyopathy.

Serum metabolomics analysis reveals amelioration effects of sea cucumber ether phospholipids on oxidative stress and inflammation in high-fat diet-fed mice

Emerging evidence suggests that sea cucumber ether phospholipids (ether-PLs) can modulate high-fat diet (HFD)-induced metabolic disorders. However, whether this modulation is associated with metabolic pathways related to oxidative stress and inflammation remains unclear. This study aimed to investigate the antioxidative and anti-inflammatory effects on HFD-fed mice and the associated metabolism pathways in response to administration with sea cucumber ether-PLs using integrated biochemistry and a metabolomics approach. Biochemistry analysis and histological examinations showed that sea cucumber ether-PLs significantly decreased body weight gain and fat deposition in tissues. PE-P was superior to PC-O in alleviating reactive oxygen species (ROS), malondialdehyde (MDA) and inflammatory responses (IL-6, TNF-α and MCP-1) in the HFD-induced mouse model. Serum metabolomics analysis revealed that it upregulated four metabolites and downregulated twenty-four metabolites compared to those in HFD mice after ether-PL administration. Pathway analysis indicated that sea cucumber ether-PLs alleviate the HFD-induced inflammation and oxidative stress by three main metabolic pathways, namely fatty acid metabolism, branched-chain amino acid (BCAA) metabolism, and trichloroacetic acid (TCA) metabolism. Taken together, sea cucumber ether-PLs showed great potential to become a natural functional food against oxidative stress and inflammation caused by HFD.

Compounds purified from edible fungi fight against chronic inflammation through oxidative stress regulation

Chronic inflammation is associated with various chronic diseases, including cardiovascular disease, neurodegenerative disease, and cancer, which severely affect the health and quality of life of people. Oxidative stress induced by unbalanced production and elimination of reactive oxygen species (ROS) is one of the essential risk factors for chronic inflammation. Recent studies, including the studies of mushrooms, which have received considerable attention, report that the antioxidant effects of natural compounds have more advantages than synthetic antioxidants. Mushrooms have been consumed by humans as precious nourishment for 3,000 years, and so far, more than 350 types have been identified in China. Mushrooms are rich in polysaccharides, peptides, polyphenols, alkaloids, and terpenoids and are associated with several healthy biological functions, especially antioxidant properties. As such, the extracts purified from mushrooms could activate the expression of antioxidant enzymes through the Keap1/Nrf2/ARE pathway to neutralize excessive ROS and inhibit ROS-induced chronic inflammation through the NF-κB pathway. Recently, the antioxidant properties of mushrooms have been successfully applied to treating cardiovascular disease (CAD), neurodegenerative diseases, diabetes mellitus, and cancer. The present review summarizes the antioxidant properties and the mechanism of compounds purified from mushrooms, emphasizing the oxidative stress regulation of mushrooms to fight against chronic inflammation.

Molecular mechanism of ferroptosis and its role in the occurrence and treatment of diabetes

Ferroptosis is an iron-dependent programmed cell death, which is different from apoptosis, necrosis, and autophagy. Specifically, under the action of divalent iron or ester oxygenase, unsaturated fatty acids that are highly expressed on the cell membrane are catalyzed to produce lipid peroxidation, which induces cell death. In addition, the expression of the antioxidant system [glutathione (GSH) and glutathione peroxidase 4 (GPX4)] is decreased. Ferroptosis plays an important role in the development of diabetes mellitus and its complications. In this article, we review the molecular mechanism of ferroptosis in the development of diabetes mellitus and its complications. We also summarize the emerging questions in this particular area of research, some of which remain unanswered. Overall, this is a comprehensive review focusing on ferroptosis-mediated diabetes and providing novel insights in the treatment of diabetes from the perspective of ferroptosis.