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Povzetek: The correct balance between reactive oxygen species and antioxidant defense in an organism is disturbed in oxidative stress. To assess oxidative balance in 36 SSc patients and 26 healthy controls (HCs), we measured reactive oxidative metabolites (ROMs), total antioxidant capacity (TAC), lipid peroxidation (measuring 4-HNE), and DNA oxidative damage (measuring 8-OHdG) in serum. Furthermore, DNA breaks in leukocytes of 35 SSc patients and 32 HCs were evaluated using COMET. While we report high ROMs for both SSc patients and age/sex matched HC samples, there was a significant increase in TAC in SSc patients as compared to HCs, and thus also a significantly higher oxidative stress index in SSc patients. TAC was significantly higher in SSc patients with ILD and gastrointestinal involvement, as well as in patients with anti-topoisomerase antibodies. We observe no difference in serum lipid peroxidation status or oxidative DNA damage. However, SSc patients had significantly more leukocyte DNA breaks than HCs; the most damage was observed in patients treated with immunosuppressives. Thus, our study confirms presence of oxidative stress and increased DNA damage in leukocytes of SSc patients; however, it points toward increased antioxidant capacity, which needs to be further studied.
Ključne besede: systemic sclerosis, oxidative stress, reactive oxidative metabolites, antioxidants, lipid peroxidation, DNA damage, DNA breaks
Objavljeno v DiRROS: 05.08.2026; Ogledov: 182; Prenosov: 73
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Povzetek: Bisphenols (BPs) are industrial chemicals extensively used in polycarbonate plastics and epoxy resins for everyday products, including food and beverage containers, toys, and thermal paper, representing major sources of human exposure. Bisphenol A (BPA) is the most prevalent; however, due to its endocrine-disrupting, reproductive, and genotoxic effects, it is classified as a substance of high concern by the European Chemicals Agency. Regulatory restrictions have prompted the use of structural analogues, including bisphenol AP (BPAP) and bisphenol C (BPC); however, emerging evidence suggests they may pose similar or greater health risks. Comprehensive data on their toxicity and human exposure, especially in mixtures, remain limited. This study assessed the cytotoxic and genotoxic effects of BPA, and less studied analogues BPAP, BPC, and their binary mixtures using a human-relevant 3D HepG2 spheroid model, representing an advanced in vitro system. Spheroids were exposed for 24 and 96 h, and effects were evaluated by ATP-based viability assays, comet assay, and targeted transcriptomics. None of the bisphenols induced significant cytotoxicity, although slight reductions in viability were observed for BPAP, BPC, and mixtures. DNA strand breaks were detected after exposure to BPA, BPC, and mixtures. Transcriptomic analysis revealed modest stress responses and strong upregulation of xenobiotic metabolism genes (CYP1A1, CYP1A2, CYP3A4, UGT1A1, NAT2), indicating cellular recognition of the tested bisphenols as bioactive xenobiotics. Antioxidant and DNA repair genes were largely unchanged, except for upregulation of oxidative stress markers HMOX1 and SRXN1 and a slight increase in OGG1, indicating oxidative DNA damage. Importantly, mixture effects were predominantly additive, with no evidence of synergistic interactions under the tested conditions. Overall, bisphenol exposure primarily triggered oxidative stress and metabolic responses rather than robust DNA damage signalling, suggesting that genotoxicity is largely mediated by reactive oxygen species. By integrating multiple endpoints in a 3D liver model, this study provides a more comprehensive assessment of bisphenol toxicity and highlights potential risks associated with BPA analogues and their mixtures, supporting the need for a comprehensive safety assessment to evaluate their suitability as replacements in consumer products.
Ključne besede: bisphenol, DNA damage, oxidative stress, complex mixtures, metabolism
Objavljeno v DiRROS: 10.07.2026; Ogledov: 178; Prenosov: 187
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Povzetek: Introduction: Acne vulgaris (AV) is a chronic inflammatory dermatosis predominantly affecting adolescents and young adults. Oxidative and nitrosative stress, marked by elevated nitric oxide (NO) and interleukin (IL)-1α, contributes to AV pathogenesis. Glutathione, a key antioxidant, may attenuate oxidative and nitrosative stress and modulate inflammatory pathways. This study investigates the effectiveness of oral glutathione supplementation on serum NO and IL-1α concentrations, and clinical improvement in mild to moderate AV patients. Methods: A randomized controlled trial was conducted involving 40 subjects diagnosed with mild to moderate AV. Participants were randomized to receive either 500 mg oral glutathione (n = 22) or placebo (n = 18) once daily for 4 weeks. Clinical severity of AV was assessed utilizing the Lehmann criteria. Serum levels of NO and IL-1α were measured at baseline and week 4. Results: At week 4, reductions in serum NO and IL-1α concentrations were observed in the glutathione group; however, these changes did not reach statistical significance (p > 0.05). Clinical improvement occurred in seven subjects (31.8%) in the glutathione group, with a reduction from moderate to mild severity. No adverse reactions were reported. Conclusions: Oral glutathione supplementation demonstrated a non-significant trend toward reducing oxidative and nitrosative stress markers and improving mild to moderate AV. Further studies are recommended to validate these findings.
Ključne besede: acne vulgaris, oxidative stress, nitric oxide, glutathione, interleukin-1α
Objavljeno v DiRROS: 15.06.2026; Ogledov: 246; Prenosov: 197
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Povzetek: As children spend up to 9 h a day in kindergarten, the main purpose of our study was to evaluate the effect of antioxidant-rich kindergarten meals on oxidative stress biomarkers (OSBs) in healthy children. In the randomized control trial with a follow-up, healthy 5–6-year-old children from six kindergartens were randomly divided into a prototype group (PG, n=40) and a control group (CG, n=17). PG followed a 2-week antioxidant-rich kindergarten meal plan (breakfast, lunch, and two snacks), and CG followed their standard kindergarten meal plans. Outside the kindergartens, participants ate as usual. We used a consecutive 7-day dietary record inside and outside the kindergarten and the national dietary assessment tool OPEN to assess the total dietary antioxidant capacity (dTAC) of the consumed foods. Malondialdehyde (MDA), 8-hydroxy-2-deoxyguanosine (8-OHdG), and four F2-isoprostane were measured in fasting urine on days 1 and 15. We also measured total antioxidant power (PAT) and hydroperoxides (d-ROMs) in fasting serum on day 15 and obtained the value of the oxidative stress index (OSI). We used a Welch two-sample t-test and multiple regression analysis to compare the prototype and control groups and a nonparametric Wilcoxon signed rank exact test to compare pre- and post-intervention results in urine. Antioxidant-rich kindergarten meals contributed to a significantly (p<0.05) higher intake of dTAC in PG participants compared to standard meals in CG participants (8.6 vs. 2.8 mmol/day). We detected a negative correlation between dTAC intake and d-ROMs and between dTAC intake and OSI (r= −0.29, p=0.043 and r= −0.31, p=0.032, respectively). A significant decrease in urinary 8-iso-15-prostaglandin-F-2 alpha was detected in PG participants between days 1 and 15; however, no other intra-individual significant differences in urinary OSBs were found.
Ključne besede: antioxidant-rich diet, oxidative stress biomarkers, dietary antioxidant capacity, reactive oxygen metabolites, F2-isoprostanes, kindergarten diet
Objavljeno v DiRROS: 08.06.2026; Ogledov: 211; Prenosov: 163
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Povzetek: Microplastic pollution is an increasing environmental issue in the marine environment due to its ubiquitous presence and its role as a vector for organic pollutants such as tributyltin (TBT). Adsorption of TBT onto microplastics (MP) can increase its availability to filter-feeding organisms by prolonging its retention time in the water column. We investigated whether polyethylene (PE) MP spheres (10–63 μm) could act as vectors for TBT transfer in the mussel Mytilus galloprovincialis by exposing it to PE MP (50 mg L− 1 ) and TBT (0.001 mg L− 1 ) separately and in co-exposure for 21 days. Efficient adsorption on PE MP was confirmed, and higher concentration of TBT was observed in the PE MP + TBT group compared to TBT only exposed group, indicating a vector effect. This led to higher toxicity in mussels, as the combined stress conditions in the PE MP + TBT group resulted in a significant decrease in the catalase activity after 14 days of the exposure. Higher ETS activity was observed in both exposed groups after seven days of exposure, followed by lower ETS activity at 14 and 21 days, indicating depletion of energy reserves. Pronounced responses in catalase and electron transport system (ETS) activity were observed in the hepatopancreas compared to the gill tissue. DNA damage was present in all exposed groups and increased over time.
Ključne besede: mytilus galloprovincialis, tributyltin, PE microplastics, mitochondrial respiration, genotoxicity, oxidative stress
Objavljeno v DiRROS: 18.05.2026; Ogledov: 276; Prenosov: 284
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