Ferroptosis, a lipid peroxidation- and iron-mediated type of regulated cell death, relates to both neuroinflammation, which is common in relapsing-remitting multiple sclerosis (RRMS), and neurodegeneration, which is prevalent in progressive (P)MS. Currently, findings related to the molecular markers proposed in this paper in patients are scarce. We analyzed circulatory molecular indicators of the main ferroptosis-related processes, comprising lipid peroxidation (malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), and hexanoyl–lysine adduct (HEL)), glutathione-related antioxidant defense (total glutathione (reduced (GSH) and oxidized (GSSG)) and glutathione peroxidase 4 (GPX4)), and iron metabolism (iron, transferrin and ferritin) to estimate their contributions to the clinical manifestation of MS and differences between RRMS and PMS disease course. In 153 patients with RRMS and 69 with PMS, plasma/serum lipid peroxidation indicators and glutathione were quantified using ELISA and colorimetric reactions, respectively. Iron serum concentrations were determined using spectrophotometry, and transferrin and ferritin were determined using immunoturbidimetry. Compared to those with RRMS, patients with PMS had decreased 4-HNE (median, 1368.42 vs. 1580.17 pg/mL; p = 0.03). Interactive effects of MS course (RRMS/PMS) and disease-modifying therapy status on MDA (p = 0.009) and HEL (p = 0.02) levels were detected. In addition, the interaction of disease course and self-reported fatigue revealed significant impacts on 4-HNE levels (p = 0.01) and the GSH/GSSG ratio (p = 0.04). The results also show an association of MS course (p = 0.03) and EDSS (p = 0.04) with GSH levels. No significant changes were observed in the serum concentrations of iron metabolism indicators between the two patient groups (p > 0.05). We suggest circulatory 4-HNE as an important parameter related to differences between RRMS and PMS. Significant interactions of MS course and other clinically relevant parameters with changes in redox processes associated with ferroptosis support the further investigation of MS with a larger sample while taking into account both circulatory and central nervous system estimation.

Cardiovascular disease (CVD) is associated with alterations in DNA methylation and polyunsaturated fatty acid (PUFA) profile, both modulated by dietary polyphenols. The present parallel, placebo-controlled study (part of the original clinical study registered as NCT02800967 at www.clinicaltrials.gov) aimed to determine the impact of 4-week daily consumption of polyphenol-rich Aronia melanocarpa juice (AMJ) treatment on Long Interspersed Nucleotide Element-1 (LINE-1) methylation in peripheral blood leukocytes and on plasma PUFAs, in subjects (n = 54, age range of 40.2 ± 6.7 years) at moderate CVD risk, including an increased body mass index, central obesity, high normal blood pressure, and/or dyslipidemia. The goal was also to examine whether factors known to affect DNA methylation (folate intake levels, MTHFR C677T gene variant, anthropometric and metabolic parameters) modulated the LINE-1 methylation levels upon the consumption of polyphenol-rich aronia juice. Experimental analysis of LINE-1 methylation was done by MethyLight method. MTHFR C677T genotypes were determined by the polymerase chain reaction–restriction fragment length polymorphism method, and folate intake was assessed by processing the data from the food frequency questionnaire. PUFAs were measured by gas–liquid chromatography, and serum lipid profile was determined by using Roche Diagnostics kits. The statistical analyses were performed using Statistica software package. In the comparison after vs. before the treatment period, in dyslipidemic women (n = 22), we observed significant decreases in LINE-1 methylation levels (97.54 ± 1.50 vs. 98.39 ± 0.86%, respectively; P = 0.01) and arachidonic acid/eicosapentaenoic acid ratio [29.17 ± 15.21 vs. 38.42 (25.96–89.58), respectively; P = 0.02]. The change (after vs. before treatment) in LINE-1 methylation directly correlated with the presence of MTHFR 677T allele, average daily folate intake, and the change in serum low-density lipoprotein cholesterol but inversely correlated with the change in serum triacylglycerols (R = 0.72, R² = 0.52, adjusted R² = 0.36, P = 0.03). The current results imply potential cardioprotective effects of habitual polyphenol-rich aronia juice consumption achieved through the modifications of DNA methylation pattern and PUFAs in subjects at CVD risk, which should be further confirmed. Hence, the precision nutrition-driven modulations of both DNA methylation and PUFA profile may become targets for new approaches in the prevention of CVD.