Background: Stroke onset in women occurs later in life compared with men. The underlying mechanisms of these differences have not been established. Epigenetic clocks, based on DNA methylation (DNAm) profiles, are the most accurate biological age estimate. Epigenetic age acceleration (EAA) measures indicate whether an individual is biologically younger or older than expected. Our aim was to analyze whether sexual dichotomy at age of stroke onset is conditioned by EAA. Methods: We used 2 DNAm datasets from whole blood samples of case-control genetic studies of ischemic stroke (IS), a discovery cohort of 374 IS patients (N women=163, N men=211), from GRECOS (Genotyping Recurrence Risk of Stroke) and SEDMAN (Dabigatran Study in the Early Phase of Stroke, New Neuroimaging Markers and Biomarkers) studies and a replication cohort of 981 IS patients (N women=411, N men=570) from BASICMAR register. We compared chronological age, 2 DNAm-based biomarkers of aging and intrinsic and extrinsic epigenetic age acceleration EAA (IEAA and extrinsic EAA, respectively), in IS as well as in individual IS etiologic subtypes. Horvath and Hannum epigenetic clocks were used to assess the aging rate. A proteomic study using the SOMAScan multiplex assay was performed on 26 samples analyzing 1305 proteins. Results: Women present lower Hannum-extrinsic EAA values, whereas men have higher Hannum-extrinsic EAA values (women=−0.64, men=1.24, P =1.34×10 ^-2 ); the same tendency was observed in the second cohort (women=−0.57, men=0.79, P =0.02). These differences seemed to be specific to cardioembolic and undetermined stroke subtypes. Additionally, 42 blood protein levels were associated with Hannum-extrinsic EAA ( P <0.05), belonging to the immune effector process ( P =1.54×10 ^-6 ) and platelet degranulation ( P <8.74×10 ^-6 ) pathways. Conclusions: This study shows that sex-specific underlying biological mechanisms associated with stroke onset could be due to differences in biological age acceleration between men and women.

Owing to the high risk of recurrence, identifying indicators of carotid plaque vulnerability in atherothrombotic ischemic stroke is essential. In this study, we aimed to identify modified LDLs and antioxidant enzymes associated with plaque vulnerability in plasma from patients with a recent ischemic stroke and carotid atherosclerosis. Patients underwent an ultrasound, a CT-angiography, and an ¹⁸F-FDG PET. A blood sample was obtained from patients (n = 64, 57.8% with stenosis ≥50%) and healthy controls (n = 24). Compared to the controls, patients showed lower levels of total cholesterol, LDL cholesterol, HDL cholesterol, apolipoprotein B (apoB), apoA-I, apoA-II, and apoE, and higher levels of apoJ. Patients showed lower platelet-activating factor acetylhydrolase (PAF-AH) and paraoxonase-1 (PON-1) enzymatic activities in HDL, and higher plasma levels of oxidized LDL (oxLDL) and electronegative LDL (LDL(−)). The only difference between patients with stenosis ≥50% and <50% was the proportion of LDL(−). In a multivariable logistic regression analysis, the levels of LDL(−), but not of oxLDL, were independently associated with the degree of carotid stenosis (OR: 5.40, CI: 1.15–25.44, p < 0.033), the presence of hypoechoic plaque (OR: 7.52, CI: 1.26–44.83, p < 0.027), and of diffuse neovessels (OR: 10.77, CI: 1.21–95.93, p < 0.033), indicating that an increased proportion of LDL(−) is associated with vulnerable atherosclerotic plaque.

Atherothrombotic stroke represents approximately 20% of all ischemic strokes. It is caused by large-artery atherosclerosis, mostly in the internal carotid artery, and it is associated with a high risk of early recurrence. After an ischemic stroke, tissue plasminogen activator is used in clinical practice, although it is not possible in all patients. In severe clinical situations, such as high carotid stenosis (≥70%), revascularization by carotid endarterectomy or by stent placement is carried out to avoid recurrences. In stroke prevention, the pharmacological recommendations are based on antithrombotic, lipid-lowering, and antihypertensive therapy. Inflammation is a promising target in stroke prevention, particularly in ischemic strokes associated with atherosclerosis. However, the use of anti-inflammatory strategies has been scarcely studied. No clinical trials are clearly successful and most preclinical studies are focused on protection after a stroke. The present review describes novel therapies addressed to counteract inflammation in the prevention of the first-ever or recurrent stroke. The putative clinical use of broad-spectrum and specific anti-inflammatory drugs, such as monoclonal antibodies and microRNAs (miRNAs) as regulators of atherosclerosis, will be outlined. Further studies are necessary to ascertain which patients may benefit from anti-inflammatory agents and how.

Background: Functional recovery from ischemic stroke (IS), the main cause of adult disability worldwide, is influenced by many factors, and a portion of interindividual variability remains unexplained.Methods: Observational study in a tertiary stroke centre of patients with IS analyzed using shotgun metagenomic sequencing (January 2020–March 2022). Functional outcomes were assessed according to modified Rankin Scale (mRS) scores 3‐months post‐IS, considering 0–2 favorable and 3–6 unfavorable. The causal relationship between several bacteria and post‐IS outcomes was explored via two‐sample Mendelian randomization (MR) analyses using Genome‐Wide Association Analysis (GWAS) summary statistics.Results: Comparing 128 patients with favorable and unfavorable post‐IS functional outcomes, β‐diversity analysis showed a separation in microbial structure, and α‐diversity measures revealed greater bacterial richness in the favorable outcomes group. Taxonomic profiling of the samples showed that a greater abundance of pathogenic bacteria (e.g., Pseudomonas, Finegoldia, Porphyromonas) was associated with an unfavorable outcome. Functional profiling of the samples revealed differences in the ethylbenzene degradation pathway and in 16S rRNA (uracil1498‐N3)‐methyltransferase. MR confirmed increased pyruvate levels to be causally associated with post‐IS favorable outcomes (β = −0.50, 95% CI: −0.91, −0.10).Conclusions: Our study points to gut microbiota differences in patients with unfavorable versus favorable 3‐month post‐IS outcomes. Patients with unfavorable outcomes presented gut microbiota dysbiosis and alterations in multiple metabolic pathways.Trial Registration: This study was registered on 3 October 2021 with https://clinicaltrials.gov. Access number: NCT04795687