Exploring the landscape of academic retractions in medicine: a comprehensive umbrella review.

INTRODUCTION: The escalating trend of academic article retractions over the last decades raises concerns about scientific integrity, but heterogeneity in retractions and reasons for them pose a major challenge. We aimed to comprehensively overview systematic reviews focusing on retractions in the biomedical literature. EVIDENCE ACQUISITION: We abstracted salient features and bibliometric details from shortlisted articles. The Joanna Briggs Institute (JBI) Checklist for Systematic Reviews and Research Syntheses was used for validity appraisal. EVIDENCE SYNTHESIS: A total of 11 reviews were included, published between 2016 and 2023, and reporting on a total of 1851 retracted studies. Several major reasons for retractions were identified, spanning both misconduct (e.g., falsification, duplication, plagiarism) and non-misconduct issues (e.g., unreliable data, publishing problems). Correlates include author-related factors (number of authors, nationality) and journal-related factors (impact factor), with repeat offenders contributing significantly. Impacts of retractions is profound, affecting scholarly credibility, public trust, and resource utilization. CONCLUSIONS: In order to prevent retractions and amend their adverse effects, rigorous and transparent reporting standards, enhanced training in research ethics, strengthened peer review processes, and the establishment of collaborative and integrated research integrity offices are proposed.

Exposure to serum from exclusive heated tobacco product smokers induces mTOR activation and fibrotic features in human cardiac stromal cells.

Chronic smokers have increased risk of fibrosis-related atrial fibrillation. The use of heated-tobacco products (HTPs) is increasing exponentially, and their health impact is still uncertain. We aim to investigate the effects of circulating molecules in exclusive HTP chronic smokers on the fibrotic behavior of human atrial cardiac stromal cells (CSCs). CSCs were isolated from atrial tissue of elective cardiac surgery patients, and exposed to serum lots from young healthy subjects, stratified in exclusive HTP smokers, tobacco combustion cigarette (TCC) smokers, or nonsmokers (NS). CSCs treated with TCC serum displayed impaired migration and increased expression of pro-inflammatory cytokines. Cells cultured with HTP serum showed increased levels of pro-fibrotic markers, and reduced expression of connexin-43. Both TCC and HTP sera increased collagen release and reduced secretion of angiogenic protective factors from CSCs, compared to NS sera. Paracrine support to tube-formation by endothelial cells and to viability of cardiomyocytes was significantly impaired. Treatment with sera of both smokers impaired H2O2/NO release balance by CSCs and reduced early phosphorylation of several pathways compared to NS serum, leading to mTOR activation. Cotreatment with rapamycin was able to reduce mTOR phosphorylation and differentiation into aSMA-positive myofibroblasts in CSCs exposed to TCC and HTP sera. In conclusion, the circulating molecules in the serum of chronic exclusive HTP smokers induce fibrotic behavior in CSCs through activation of the mTOR pathway, and reduce their beneficial paracrine effects on endothelial cells and cardiomyocytes. These results point to a potential risk for cardiac fibrosis in chronic HTP users.

Towards the Fifth Pillar for the Treatment of Heart Failure with Reduced Ejection Fraction: Vericiguat in Older and Complex Patients.

Heart failure with reduced ejection fraction (HFrEF) represents an emerging epidemic, particularly affecting frail, older, and multimorbid patients. Current therapy for the management of HFrEF includes four different classes of disease-modifying drugs, commonly referred to as 'four pillars', which target the neurohormonal system that is overactivated in HF and contributes to its progression. These classes of drugs include ß-blockers, inhibitors of the renin-angiotensin-aldosterone system, mineralocorticoid receptor antagonists, and sodium-glucose co-transporter-2 (SGLT2) inhibitors. Unfortunately, these agents cannot be administered as frequently as needed to older patients because of poor tolerability and comorbidities. In addition, although these drugs have dramatically increased the survival expectations of patients with HF, their residual risk of rehospitalization and death at 5 years remains considerable. Vericiguat, a soluble guanylate cyclase (sGC) stimulator, was reported to exert beneficial effects in patients with worsening HF, including older subjects, reducing the rate of both hospitalizations and deaths, with limited adverse effects and drug interaction. In this narrative review, we present the current state of art on vericiguat, with a particular focus on elderly and frail patients.

Oleuropein, a Component of Extra Virgin Olive Oil, Improves Liver Steatosis and Lobular Inflammation by Lipopolysaccharides-TLR4 Axis Downregulation.

Gut-dysbiosis-induced lipopolysaccharides (LPS) translocation into systemic circulation has been suggested to be implicated in nonalcoholic fatty liver disease (NAFLD) pathogenesis. This study aimed to assess if oleuropein (OLE), a component of extra virgin olive oil, lowers high-fat-diet (HFD)-induced endotoxemia and, eventually, liver steatosis. An immunohistochemistry analysis of the intestine and liver was performed in (i) control mice (CTR; n = 15), (ii) high-fat-diet fed (HFD) mice (HFD; n = 16), and (iii) HFD mice treated with 6 µg/day of OLE for 30 days (HFD + OLE, n = 13). The HFD mice developed significant liver steatosis compared to the controls, an effect that was significantly reduced in the HFD + OLE-treated mice. The amount of hepatocyte LPS localization and the number of TLR4+ macrophages were higher in the HFD mice in the than controls and were lowered in the HFD + OLE-treated mice. The number of CD42b+ platelets was increased in the liver sinusoids of the HFD mice compared to the controls and decreased in the HFD + OLE-treated mice. Compared to the controls, the HFD-treated mice showed a high percentage of intestine PAS+ goblet cells, an increased length of intestinal crypts, LPS localization and TLR4+ expression, and occludin downregulation, an effect counteracted in the HFD + OLE-treated mice. The HFD-fed animals displayed increased systemic levels of LPS and zonulin, but they were reduced in the HFD + OLE-treated animals. It can be seen that OLE administration improves liver steatosis and inflammation in association with decreased LPS translocation into the systemic circulation, hepatocyte localization of LPS and TLR4 downregulation in HFD-induced mouse model of NAFLD.

Prediction of 30-day mortality after surgery for infective endocarditis using risk scores: Insights from a European multicenter comparative validation study.

BACKGROUND: It remains unclear today whether risk scores created specifically to predict early mortality after cardiac operations for infective endocarditis (IE) outperform or not the European System for Cardiac Operative Risk Evaluation II (EuroSCORE II). METHODS: Perioperative data and outcomes from a European multicenter series of patients undergoing surgery for definite IE were retrospectively reviewed. Only the cases with known pathogen and without missing values for all considered variables were retained for analyses. A comparative validation of EuroSCORE II and 5 specific risk scores for early mortality after surgery for IE-(1) STS-IE (Society of Thoracic Surgeons for IE); (2) PALSUSE (Prosthetic valve, Age ≥70, Large intracardiac destruction, Staphylococcus spp, Urgent surgery, Sex (female), EuroSCORE ≥10); (3) ANCLA (Anemia, New York Heart Association class IV, Critical state, Large intracardiac destruction, surgery on thoracic Aorta); (4) AEPEI II (Association pour l'Étude et la Prévention de l'Endocardite Infectieuse II); (5) APORTEI (Análisis de los factores PROnósticos en el Tratamiento quirúrgico de la Endocarditis Infecciosa)-was carried out using calibration plot and receiver-operating characteristic curve analysis. Areas under the curve (AUCs) were compared 1:1 according to the Hanley-McNeil's method. The agreement between APORTEI score and EuroSCORE II of the 30-day mortality prediction after surgery was also appraised. RESULTS: A total of 1,012 patients from 5 European university-affiliated centers underwent 1,036 cardiac operations, with a 30-day mortality after surgery of 9.7%. All IE-specific risk scores considered achieved better results than EuroSCORE II in terms of calibration; AEPEI II and APORTEI score showed the best performances. Despite poor calibration, EuroSCORE II overcame in discrimination every specific risk score (AUC, 0.751 vs 0.693 or less, P = .01 or less). For a higher/lesser than 20% expected mortality, the agreement of prediction between APORTEI score and EuroSCORE II was 86%. CONCLUSION: EuroSCORE II discrimination for 30-day mortality after surgery for IE was higher than 5 established IE-specific risk scores. AEPEI II and APORTEI score showed the best results in terms of calibration.

CAR, mGPS and hs-mGPS: What is among them the best gero-biomarker for age-related diseases? And for what clinical application?

The identification of biomarkers linked to the onset, progression, and prevention of age-related diseases (ARD), in the era of personalized medicine, represents the best goal of geroscience. Geroscience has the fundamental role of exploring and identifying the biological mechanisms of aging to suggest interventions capable of stopping/delaying the many pathological conditions and disabilities related to age. Therefore, it has become its key priority, as well as that of clinical practice and research, based on identifying and validating a range of biomarkers, geromarkers, which can be used to diagnostic, prognostic, or predictive clinical purposes. Indeed, geromarkers have, the potential to predict ARD trajectories and facilitate targeted interventions to slow down the related disabilities. Here our attention is paid to the inflammatory indexes (CAR, mGPS, hs-mGPS) linked to the relationship between the plasma levels of two inflammatory analytes, the typical positive protein of the acute phase, and the negative one, i.e. c-reactive protein (CRP) and albumin, respectively. These indexes allow us to understand the magnitude of the two main mechanisms predicted to influence the aging process, including inflammation and immunosenescence, as well as the degree of ARD severity. Evidence on their relationship with ARD is widely reported and discussed, to understand which can represent the best ARD geromarker, and its clinical application.

ECMO Alone Versus ECPELLA in Patients Affected by Cardiogenic Shock: The Multicenter EVACS Study.

The objective was to investigate the outcomes of concomitant venoarterial extracorporeal membrane oxygenation (ECMO) and left ventricular unloading with Impella (ECPELLA) compared with ECMO alone to treat patients affected by cardiogenic shock. Data from patients needing mechanical circulatory support from 4 international centers were analyzed. Of 438 patients included, ECMO alone and ECPELLA were adopted in 319 (72.8%) and 119 (27.2%) patients, respectively. Propensity score matching analysis identified 95 pairs. In the matched cohort, 30-day mortality rates in the ECMO and ECPELLA were 49.5% and 43.2% ( P = 0.467). The incidences of complications did not differ significantly between groups ( P = 0.877, P = 0.629, P = 1.000, respectively). After a median follow-up of 0.18 years (interquartile range 0.02-2.55), the use of ECPELLA was associated with similar mortality compared with ECMO alone (hazard ratio 0.81, 95% confidence interval 0.54-1.20, P = 0.285), with 1-year overall survival rates of 51.3% and 46.6%, for ECPELLA and ECMO alone, respectively. ECMO alone and ECPELLA are both effective strategies in patients needing mechanical circulatory support for cardiogenic shock, showing similar rates of early and mid-term survival.

NOX2 as a Biomarker of Academic Performance: Evidence from University Students during Examination.

BACKGROUND: Cortisol levels, oxidative stress, and lower cerebral performance seem to be closely related. This study aimed to evaluate the question of whether exam stress affected oxidative stress and endothelial function parameters in the salivary samples of students. METHODS: A total of 114 healthy students were recruited. All students were subjected to a 21-item DASS questionnaire to assess perceived stress. Cortisol levels, biomarkers of oxidative stress, and endothelial function were evaluated at T0, during the semester, and T1, in the morning before the exam, in saliva samples. In vitro, HUVECs were stimulated with cortisol, and oxidative stress and endothelial function parameters were evaluated. RESULTS: At T1, cortisol levels were significantly increased compared with the levels during the semester. Moreover, exam results correlated inversely with the DASS score at T1. In addition, NOX2, H2O2 and endothelin-1 significantly increased, while NO bioavailability decreased. In vitro, HUVECs treatment with human cortisol determined the increase of oxidative stress and the decrease of endothelial function, in association with impaired eNOS phosphorylation. CONCLUSION: NOX2-mediated oxidative stress is a mechanism that could mediate cortisol-induced transient endothelial dysfunction during academic examination. Therefore, strategies to monitor or modulate oxidative stress could help students to reduce the impact of examination-related stress.

Comparative effects of different antiplatelet strategies in carriers of CYP2C19 loss-of-function alleles: a network meta-analysis.

BACKGROUND: Carriers of cytochrome 2C19 (CYP2C19) loss of function (LoF) alleles treated with clopidogrel have impaired drug metabolism resulting in reduced active metabolite levels, high platelet reactivity (HPR), and an increased risk of thrombotic events. Several alternative antiplatelet therapies have been proposed to overcome HPR in these patients, but their comparative effects remain poorly explored. METHODS: Randomized controlled trials (RCTs) comparing different oral antiplatelet therapies in carriers of CYP2C19 LoF alleles undergoing percutaneous coronary interventions (PCI) were included. A frequentist network meta-analysis was conducted to estimate mean difference (MD) or odds ratios (OR) and 95% confidence intervals (CI). The primary outcome was platelet reactivity assessed by VerifyNow and reported as P2Y12 reaction unit (PRU). The secondary outcome was the rate of HPR. Standard-dose of clopidogrel (75 mg daily) was used as reference treatment. RESULTS: A total of 12 RCTs testing 6 alternative strategies (i.e., clopidogrel 150 mg, prasugrel 3.75 mg, 5 mg, and 10 mg, ticagrelor 90 mg bid, and adjunctive cilostazol 100 mg bid) were included in the network. Compared with standard-dose clopidogrel, the greatest reduction in PRU was observed with prasugrel 10 mg (MD -127.91; 95% CI -141.04; -114.78) and ticagrelor 90 mg bid (MD -124.91; 95% CI -161.78; -88.04), followed by prasugrel 5 mg (MD -76.33; 95% CI -98.01; -54.65) and prasugrel 3.75 mg (MD -73.00; 95% CI -100.28; -45.72). Among other strategies, adjunctive cilostazol (MD-42.64; 95% CI -64.72; -20.57) and high-dose clopidogrel (MD -32.11; 95% CI -51.33; -12.90) were associated with a modest reduction in PRU compared with standard-dose clopidogrel. CONCLUSION: Among carriers of CYP2C19 LoF alleles undergoing PCI, standard-dose prasugrel or ticagrelor are most effective in reducing platelet reactivity, while double-dose clopidogrel and additional cilostazol showed modest effects. Reduced-dose of prasugrel may represent a balanced strategy to overcome HPR without a significant increase in bleeding. The clinical implications of these pharmacodynamic findings warrant further investigation.

Comparative diagnostic accuracy of transcranial Doppler and contrast-enhanced transthoracic echocardiography for the diagnosis of patent foramen ovale and atrial septal defect.

BACKGROUND: Recognition of right-to-left shunt is crucial in the work-up of patients with suspected patent foramen ovale (PFO) or atrial septal defect (ASD). While transesophageal echocardiography (TEE) remains the gold standard diagnostic tool for the anatomic assessment of PFO/ASD, transcranial Doppler (TCD) and contrast-enhanced transthoracic echocardiogram (CE-TTE) hold the promise of providing minimally invasive yet accurate clinical details. Their comparative accuracy remains however debated. METHODS: We conducted a retrospective observational study leveraging our extensive institutional experience with systematic TCD and CE-TTE in patients with suspected PFO/ASD. Several measures of diagnostic test accuracy were computed, with point estimates and 95% confidence intervals, when applicable. RESULTS: A total of 1358 patients were included, with age 48±14 years and 772 (58%) women. Tests were performed for diagnostic purposes in 797 (58.6%) and during follow-up in 740 (54.5%). A PFO was eventually diagnosed in 1038 (77.9%) patients, and an ASD in 60 (4.5%). Agreement between TCD and CE-TTE occurred in 1309 (85.2%) cases, with TCD yielding worse findings than CE-TTE in 91 (5.9%) patients, and vice versa in 137 (8.9%), yielding a Cohen kappa of 78.6% (95% CI: 76.3-81.1%) and a highly significant P value at McNemar test (P<0.001). After dichotomization, and using TCD as benchmark, CE-TTE yielded sensitivity 96.9%, specificity 95.1%, area under the curve 92.1%, and P=0.249. Similar findings were obtained when focusing only on diagnostic tests or follow-up ones (Cohen kappa respectively 74.0% [70.2-77.1%], P<0.001 and 80.3% [76.4-84.3%], P<0.001). Notably, Valsalva was necessary to disclose the presence of shunt during TCD in 487 (31.7%) patients and during CE-TTE in 482 (31.4%) cases. Finally, performance of TCD and CE-TTE in a subset of patients eventually undergoing TTE was quite similar. CONCLUSIONS: The diagnostic accuracy of CE-TTE appears favorable, and this imaging test may identify patients who may be missed if only TCD is used to screen patients with suspected PFO/ASD. Accordingly, CE-TTE is recommended as an adjunct diagnostic modality for all patients with a high pre-test probability of PFO/ASD and right-to-left shunt.

Mitophagy modulation for the treatment of cardiovascular diseases.

BACKGROUND: Defects of mitophagy, the selective form of autophagy for mitochondria, are commonly observed in several cardiovascular diseases and represent the main cause of mitochondrial dysfunction. For this reason, mitophagy has emerged as a novel and potential therapeutic target. METHODS: In this review, we discuss current evidence about the biological significance of mitophagy in relevant preclinical models of cardiac and vascular diseases, such as heart failure, ischemia/reperfusion injury, metabolic cardiomyopathy and atherosclerosis. RESULTS: Multiple studies have shown that cardiac and vascular mitophagy is an adaptive mechanism in response to stress, contributing to cardiovascular homeostasis. Mitophagy defects lead to cell death, ultimately impairing cardiac and vascular function, whereas restoration of mitophagy by specific compounds delays disease progression. CONCLUSIONS: Despite previous efforts, the molecular mechanisms underlying mitophagy activation in response to stress are not fully characterized. A comprehensive understanding of different forms of mitophagy active in the cardiovascular system is extremely important for the development of new drugs targeting this process. Human studies evaluating mitophagy abnormalities in patients at high cardiovascular risk also represent a future challenge.

Impact of heat-not-burn cigarette passive smoking on children's oxidative stress, endothelial and platelet function.

Growing global use of heat-not-burn cigarettes (HNBC) prompts investigation. Prior studies assessed HNBC's effects on cardiovascular health, revealing heightened oxidative stress, platelet activation, and endothelial dysfunction. However, limited understanding exists regarding passive smoking's impact on children exposed to HNBC. This study aims to assess levels of oxidative stress, endothelial and platelet function among children exposed to passive smoke from HNBC, traditional tobacco (TT) cigarettes and unexposed subjects. Seventy-eight children (2-18 years) were divided into three groups: HNBC passive smokers (n = 26), TT cigarette exposed (n = 26), and control (CNT) group (n = 26, unexposed). Oxidative stress was evaluated by serum NADPH oxidase-2 (NOX2) activity, assessed by soluble Nox2-derived peptide (sNOX2-dp), isoprostanes, hydrogen peroxide (H2O2) production, hydrogen break-down activity (HBA) and NO bioavailability. Endothelial function was assessed by brachial flow-mediated dilation (FMD). Platelet function was evaluated by soluble CD40 ligand (sCD40L), soluble P-selectin (sP-selectin) and thrombus formation by T-TAS analysis. Passive smoking-exposed children (both HNBC and TT) exhibited significantly increased serum sNOX2-dp, isoprostanes, H2O2, sCD40L sP-selectin and thrombus formation versus controls. Conversely, exposed children displayed reduced brachial FMD and serum NO bioavailability. No significant differences were found between children exposed to passive smoking of HNBC vs TT. Multivariable regression linked sNOX2 (standardized coefficient ß: 0.284; SE: 0.040; p = 0.01) and H2O2 (standardized coefficient ß: 0.243; SE: 0.0; p = 0.02) as independent predictors of FMD, and isoprostanes (standardized coefficient ß:0.388; SE: 0.022; p < 0.001) and serum cotinine (standardized coefficient ß:0.270; SE: 0.048; p = 0.01) with sNOX2-dp levels. Exposure to HNBC smoke heightened oxidative stress, endothelial dysfunction, platelet activation, and thrombus formation in children. Findings suggest avenues for interventions to curb childhood passive smoking exposure.

Effect of traditional or heat-not-burn cigarette smoking on circulating miRNAs in healthy subjects.

BACKGROUND: Traditional combustion cigarette (TCC) smoking is an established risk factor for several types of cancer and cardiovascular diseases. Circulating microRNAs (miRNAs) represent key molecules mediating pathogenetic mechanisms, and potential biomarkers for personalized risk assessment. TCC smoking globally changes the profile of circulating miRNAs. The use of heat-not-burn cigarettes (HNBCs) as alternative smoking devices is rising exponentially worldwide, and the circulating miRNA profile of chronic HNBC smokers is unknown. We aimed at defining the circulating miRNA profile of chronic exclusive HNBC smokers, and identifying potentially pathogenetic signatures. METHODS: Serum samples were obtained from 60 healthy young subjects, stratified in chronic HNBC smokers, TCC smokers and nonsmokers (20 subjects each). Three pooled samples per group were used for small RNA sequencing, and the fourth subgroup constituted the validation set. RESULTS: Differential expression analysis revealed 108 differentially expressed miRNAs; 72 exclusively in TCC, 10 exclusively in HNBC and 26 in both smoker groups. KEGG pathway analysis on target genes of the commonly modulated miRNAs returned cancer and cardiovascular disease associated pathways. Stringent abundance and fold-change criteria nailed down our functional bioinformatic analyses to a network where miR-25-3p and miR-221-3p are main hubs. CONCLUSION: Our results define for the first time the miRNA profile in the serum of exclusive chronic HNBC smokers and suggest a significant impact of HNBCs on circulating miRNAs.

Low-grade endotoxemia is associated with cardiovascular events in community-acquired pneumonia.

OBJECTIVES: Community-acquired pneumonia (CAP) is associated with low-grade endotoxemia but its relationship with cardiovascular events (CVE) has not been investigated. METHODS: We evaluated the incidence of CVE including myocardial infarction, stroke, and cardiovascular death in 523 adult patients hospitalized for CAP. Serum lipopolysaccharide (LPS) and zonulin, a marker of gut permeability, were analyzed in the cohort, that was followed-up during hospitalization and up to 43 months thereafter. RESULTS: During the hospital-stay, 55 patients experienced CVE with a progressive increase from the lowest (0.6%) to highest LPS tertile (23.6%, p < 0.001). Logistic regression analyses showed that higher LPS tertile was independently associated with CVE; LPS significantly correlated with age, hs-CRP and zonulin. In a sub-group of 23 CAP patients, blood E. coli DNA was higher in patients compared to 24 controls and correlated with LPS. During the long-term follow-up, 102 new CVE were registered; the highest tertile of LPS levels was associated with incident CVE; Cox regression analysis showed that LPS tertiles, age, history of CHD, and diabetes independently predicted CVE. CONCLUSIONS: In CAP low-grade endotoxemia is associated to short- and long-term risk of CVE. Further study is necessary to assess if lowering LPS by non-absorbable antibiotics may result in improved outcomes.

Genome editing for sickle cell disease: still time to correct?

Sickle cell disease (SCD) is an inherited blood disorder, due to a single point mutation in the ß-globin gene (HBB) leading to multisystemic manifestations and it affects millions of people worldwide. The monogenic nature of the disease and the availability of autologous hematopoietic stem cells (HSCs) make this disorder an ideal candidate for gene modification strategies. Notably, significant advances in the field of gene therapy and genome editing that took place in the last decade enabled the possibility to develop several strategies for the treatment of SCD. These curative approaches were firstly based on the correction of disease-causing mutations holding the promise for a specific, effective and safe option for patients. Specifically, gene-editing approaches exploiting the homology directed repair pathway were investigated, but soon their limited efficacy in quiescent HSC has curbed their wider development. On the other hand, a number of studies on globin gene regulation, led to the development of several genome editing strategies based on the reactivation of the fetal γ-globin gene (HBG) by nuclease-mediated targeting of HBG-repressor elements. Although the efficiency of these strategies seems to be confirmed in preclinical and clinical studies, very little is known about the long-term consequences of these modifications. Moreover, the potential genotoxicity of these nuclease-based strategies must be taken into account, especially when associated with high targeting rates. The recent introduction of nuclease-free genome editing technologies brought along the potential for safer strategies for SCD gene correction, which may also harbor significant advantages over HBG-reactivating ones. In this Review, we discuss the recent advances in genome editing strategies for the correction of SCD-causing mutations trying to recapitulate the promising strategies currently available and their relative strengths and weaknesses.

Dark Chocolate Intake Positively Modulates Gut Permeability in Elite Football Athletes: A Randomized Controlled Study.

Gut barrier disruption can lead to enhanced intestinal permeability, which allows endotoxins, pathogens, and other proinflammatory substances to move through the intestinal barrier into circulation. Intense exercise over a prolonged period increases intestinal permeability, which can be further worsened by the increased production of reactive oxygen species (ROS) and pro-inflammatory cytokines. The aim of this study was to assess the degree of intestinal permeability in elite football players and to exploit the effect of cocoa polyphenols on intestinal permeability induced by intensive physical exercise. Biomarkers of intestinal permeability, such as circulating levels of zonulin, a modulator of tight junctions, occludin, a tight junction protein, and LPS translocation, were evaluated in 24 elite football players and 23 amateur athletes. Moreover, 24 elite football players were randomly assigned to either a dark chocolate (>85% cocoa) intake (n = 12) or a control group (n = 12) for 30 days in a randomized controlled trial. Biochemical analyses were performed at baseline and after 30 days of chocolate intake. Compared to amateur athletes, elite football players showed increased intestinal permeability as indicated by higher levels of zonulin, occludin, and LPS. After 30 days of dark chocolate intake, decreased intestinal permeability was found in elite athletes consuming dark chocolate. In the control group, no changes were observed. In vitro, polyphenol extracts significantly improved intestinal damage in the human intestinal mucosa cell line Caco-2. These results indicate that chronic supplementation with dark chocolate as a rich source of polyphenols positively modulates exercise-induced intestinal damage in elite football athletes.