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Öğe Can dynamic thiol-disulfide homeostasis be an effective marker in the diagnosis of nodular goiter and thyroid cancer?(2023) Aydin, Altan; Bulus, Hakan; Alişik, Murat; Erel, ÖzcanAim: The oxidative stress has an important role in thyroid pathologies by nature of thyroid gland. Dynamic thiol-disulfide homeostasis is one of the markers of oxidative stress and its counterpart antioxidants in the body. In our study, the dynamic thiol-disulfide homeostasis was investigated in cases underwent surgery due to thyroid cancer or nodular goiter. Material and Methods: The study included patients who underwent thyroidectomy in General Surgery Department of Keçiören Teaching and Research Hospital between 01.03.2017 and 01.06.2017. The patients were assigned into groups according to postoperative histopathological examination: group 1 included patients with benign lesion in histopathology report and group 2 included patients with malignant lesions in histopathology report. The patients who had no pathology in sonography and did not undergo surgery were assigned into group 3 as controls. In all patients, venous blood samples were drawn to evaluate dynamic thiol-disulfide homeostasis before surgery. Results: In the study, 98 cases underwent bilateral total thyroidectomy; 77 of which had benign disease and 21 of which had malignant disease. Native thiol values (µmol/L) were 317.4±4.2, 349.9±7.9 and 299.9±7.9 (p=0) while total thiol values (µmol/L) were 353.5±4.8, 386.5±9.5 and 332.6±8.3 (p=0) and disulfide values (µmol/L) were 18.4±0.5, 20.5±0.7 and 16.7±0.6 (p=0) in group 1 (benign disease), group 2 (malignant disease) and group 3 (controls), respectively. In addition disulfide: native thiol was 5.8±0.1, 5.9±0.2 and 5.7±0.2 (p=0.8) while disulfide: total thiol was 5.2±0.1, 5.4±0.2 and 5.1±0.2 and native thiol: total thiol was 89.9±0.5, 90.7±0.5 and 90.5±1.5 (p=0.4) in group 1, 2 and 3, respectively. Conclusion: The dynamic thiol-disulfide homeostasis can be used as a marked in the thyroid diseases; however, further studies with larger sample are needed.Öğe Comparative analysis of thiol-disulfide homeostasis dynamics between elective cesarean section and uncomplicated vaginal delivery: Insights into perinatal oxidative balance(Verduci Publisher, 2024) Çendek, Büşra Demir; Bayraktar, Bilge; Tonyalı, Nazan Vanlı; Çakır, Betül Tokgöz; Alışık, Murat; Koç, Sevgi; Erel, ÖzcanOBJECTIVE: Thiols are organic compounds containing sulfhydryl groups that exert antioxidant effects via dynamic thiol-disulfide homeostasis. The shift towards disulfide indicates the presence of an oxidative environment. Different modes of delivery can affect thiol-disulfide homeostasis. Accordingly, we planned this research to evaluate the effects of the mode of delivery on thiol-disulfide homeostasis in both maternal serum and fetal cord blood samples. PATIENTS AND METHODS: We conducted a prospective case -control study involving two groups: vaginal delivery (n=50) and elective cesarean section (CS) (n=45). The vaginal delivery group exclusively comprised uncomplicated term deliveries, while the CS group included pregnant individuals with scheduled cesarean deliveries due to the absence of spontaneous labor onset. Maternal serum and fetal cord blood samples were collected, and thiol-disulfide exchanges were analyzed using an automated method capable of measuring both aspects of the thiol-disulfide balance. RESULTS: The levels of native thiol (-SH) and total thiol in both maternal serum and fetal cord blood samples were significantly higher in the vaginal delivery group than those in the CS group. An important discovery of our study was that fetal cord disulfide (-SS) level, which may reflect oxidative stress, was higher in newborns born via vaginal delivery when examined alone. However, in both maternal and fetal cord blood, the combined ratios, SS/SH ratio (%), SS/ Total thiol ratio (%), and SH/Total thiol ratio (%) were observed to be similar between the groups in both maternal and fetal cord blood. It was observed that as the mother's weight gained during pregnancy increased, SS/SH and SS/total thiol increased (positive correlation), while SH/total thiol decreased (negative correlation). CONCLUSIONS: Our results showed that the dynamic thiol-disulfide homeostasis was greatly influenced by the way of delivery and supported the idea that vaginally-delivered infants may have more oxidative stress.Öğe A comprehensive study of oxidative stress in patients with somatic symptom disorder(Cambridge University Press, 2019) Şahin, Esra Kabadayı; Çayköylü, Ali; Şenat, Almila; Erel, ÖzcanObjective To investigate oxidative stress parameters [total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), paraoxonase (PON), arylesterase (ARE) and thiol-disulphide homeostasis] in patients who were diagnosed as having somatic symptom disorder in accordance with Diagnostic and Statistical Manual of Mental Disorders-5. Methods The study included 41 medication-free patients with somatic symptom disorder and 47 age, sex, and sociodemographic-matched healthy individuals. The patients were administered the Patient Health Questionnaire-15, Somatic Symptom Amplification Scale, Beck Depression Inventory, and Beck Anxiety Inventory. TOS, TAS, OSI, PON, ARE thiol, disulphide levels, and routine biochemical parameters were compared between the two groups. Results TOS, OSI, disulphide levels, disulphide/native thiol, and disulphide/total thiol ratios were found significantly higher in the patient group compared with the control group (p < 0.001). There was no significant difference in PON, ARE, and TAS parameters between the two groups (p > 0.05). Conclusion This study showed that the level of oxidants increased and oxidative balance was impaired in somatic symptom disorder. Oxidative stress may play a role in the aetiopathogenesis of this disorder. This is the first study to report an association between oxidative stress and somatic symptom disorder.Öğe Erythrocyte reduced/oxidized glutathione and serum thiol/disulfide homeostasis in patients with rheumatoid arthritis(Pergamon-Elsevier Science Ltd, 2021) Alışık, Murat; Alışık, Tuğba; Nacır, Barış; Neşelioğlu, Salim; Işık, İrem Genç; Koyuncu, Pınar; Erel, ÖzcanBackground: Chronic inflammation and oxidative stress are the most known mechanisms in Rheumatoid Arthritis (RA) pathophysiology, which is still not fully elucidated. In this study, we evaluated oxidative status by determining intracellular reduced/oxidized glutathione (GSH/GSSG) homeostasis and serum thiol/disulfide (SH/SS) homeostasis in RA patients. Methods: A total of 152 RA patient and 89 healthy controls were included in the study. RA patients were subdivided according to disease activity score-28 (DAS-28) as active RA and remission RA. Intracellular GSH/GSSG and serum SH/SS homeostasis parameters were analyzed. Results: Median (1st-3rd quartile values) SS/SH and GSSG/GSH percent ratio levels were significantly higher in RA patients (6.94 (6.02-8.54) and 69.8 (44.05-85.29); respectively) compared to controls (4.62 (4.15-5.46) and 34.9 (22.43-62.2); respectively) (p < 0.05 for all). SS/SH and GSSG/GSH percent ratio levels were significantly higher in active RA patients when compared to remission RA patients and controls (p < 0.05 for all). SS/SH and GSSG/GSH percent ratios were significantly increased in remission RA group compared to controls (p < 0.05 for all). DAS28 scores were positively correlated with SS/SH and GSSG/GSH percent ratios (rho = 0.259 and 0.296; respectively). Conclusions: These findings suggest that active intracellular and extracellular thiol group oxidation process might play a role in RA pathogenesis and further work in these areas may be warranted to show potential value of evaluating intracellular GSSG/GSH and serum SH/SS balances together in disease monitoring.Öğe Evaluation of dysfunctional high-density lipoprotein levels with myeloperoxidase/paraoxonase-1 ratio in rheumatoid arthritis(Wiley, 2021) Alışık, Tuğba; Alışık, Murat; Nacır, Barış; Ayhan, Fikriye Figen; Genç, Hakan; Erel, ÖzcanBackground The aim of this study is to evaluate dysfunctional high-density lipoprotein cholesterol (HDL) by measuring myeloperoxidase (MPO)/paraoxonase 1 (PON1) ratio in patients with rheumatoid arthritis (RA) and to investigate the relationship between dysfunctional HDL and cardiovascular disease (CVD) in RA patients. Methods Sixty-seven healthy individuals and 130 RA patients were included in the study. Routine lipid panels (triglyceride (TG), low-density lipoprotein cholesterol (LDL), HDL, total cholesterol (TC), PON1 and MPO levels were measured. Disease activity scores-28 (DAS28) of RA patients were calculated. Cardiological examination records of the patients were assessed to detect patients who also have CVD. Results There were no significant differences between RA and control groups in routine lipid profiles (P > .05 for all). MPO/PON1 ratios were significantly elevated in the RA group compared with the control group (P < .001). MPO/PON1 ratios were higher in RA patients with CVD history compared with those without CVD (P < .05). MPO/PON1 ratios were correlated with DAS28 scores (rho: 0.357, P < .001). Conclusion HDL dysfunction determined by the MPO/PON1 ratio may be associated with the pathophysiology of increased CVD in RA. Thus, evaluating dysfunctional HDL levels by measuring the MPO/PON1 ratio in RA patients may allow more detailed patient follow-up, as well as the reduction of CVD events in RA patients with therapeutic agents aiming to increase the functional properties of HDL by decreasing this ratio.Öğe How do thiol disulfide balance and copper-ceruloplasmin levels change in women using copper intrauterine devices?(Taylor & Francis Ltd, 2022) Korkmaz, Hilal; Deveci, Canan Dura; Alışık, Murat; Korkmaz, Vakkas; Kurdoğlu, Zehra; Erel, ÖzcanObjectives We aimed to examine the change in plasma copper (Cu) level and copper transport proteins level before inserting Cu-IUD and after one menstrual cycle and to show the effect of this change on the thiol disulfide balance in women using copper-containing intrauterine device (Cu-IUD). Method Thirty-three reproductive women who admitted to the gynecology clinic and inserted Cu-IUD were examined in this study. Thiol-disulfide homeostasis, plasma Cu and ceruloplasmin levels and ceruloplasmin ferroxidase activity were measured using the blood samples collected just before inserting Cu-IUD and after one menstrual cycle. Results Plasma copper level (p = 0.006), ceruloplasmin (p < 0.001), Ceruloplasmin Ferroxidase (p = 0.005), thiol disulfide homeostasis parameters; native thiol (NT) (p = 0.004), and total thiol (p = 0.003) levels increased significantly. Conclusion After one menstrual cycle in women inserted intrauterine Cu-IUD for contraception, plasma levels of Cu, which is the oxidant molecule, increased significantly. Both plasma ceruloplasmin level and ceruloplasmin ferroxidase activity increased due to elevated Cu levels. This increased oxidant status in the acute period was balanced by the increase in the native thiol level.Öğe The impact of oxytocin on thiol/disulphide and malonyldialdehyde/glutathione homeostasis in stressed rats(Walter De Gruyter Gmbh, 2020) Korkmaz, Hilal; Önal, Deniz; Alışık, Murat; Erel, Özcan; Pehlivanoğlu, BilgeWe aimed to investigate the impact of oxytocin on serum thiol/disulphide and malonylyldialdehyde (MDA)/glutathione balance under acute stress (AS) and chronic stress (CS) exposure in rats. Animals were allocated into control (C), AS and CS groups, then the groups subdivided as intranasal oxytocin or saline applied groups, randomly. Animals in the AS or CS groups were exposed to combined cold-immobilisation stress. Salivary corticosterone levels and elevated plus maze (EPM) scores were used to assess stress response. MDA, glutathione, thiol-disulphide levels were measured in the serum samples. Oxytocin treatment attenuated stress response regardless of the stress duration verified by lower corticosterone level and favorable profile in EPM parameters measured. Furthermore, oxytocin modulated oxidant profile suggesting lowered oxidant stress with decreased serum MDA/ glutathione and disulfide/native thiol ratios. Oxytocin improves the response of organism to stress via both its anxiolytic and antioxidant effects. That's why it can be considered as a protective measure to employ methods to increase endogenous oxytocin and/or to apply exogenous oxytocin to prevent stress-induced increase in oxidant stress, which plays a pivotal role in the pathogenesis of various stress-related diseases.Öğe A NOVEL AND SEMIAUTOMATED ASSAY FOR THIOL OXIDATIVE STRESS INDEX: TOSI(2020) Neselioglu, Salim; Şenat, Almila; Oğuz, Esra Firat; Alişik, Murat; Erel, ÖzcanObjective: The aim of the study is to develop a new andautomated method determining irreversible and reversible thioloxidation products which are formed by the exposure of theplasma to oxidation and to measure the resistance of thiolgroups to oxidation.Material and Methods: The method is based on thioldisulphidehomeostasis measurement of plasma thiol groupsbefore and after exposure to oxidative stress. According to themeasurements, the levels of reversible thiol oxidation products(RTOP), irreversible thiol oxidation products (ITOP), and thioloxidative stress index (TOSI=ITOP/RTOP) were determined.Results: Plasma levels of ITOP were 24.02±12.1 ?mol/L, levelsof RTOP were 26.68±14.96 ?mol/L and TOSI was 0.67±0.60 inthe healthy control group. The level of ITOP of patients withlung and colon cancer were found to be significantly higher thanthe control group, while the level of RTOP was found to besignificantly lower. When the parameter of TOSI which wasused to determine the direction of the balance was examined, itwas observed that the formation of ITOP was more dominant inboth colon and lung cancer patients when compared to thecontrol group.Conclusion: Practical, inexpensive and semi-automaticspectrophotometric RTOP, ITOP and TOSI tests, developed byus for the first time, can be used to investigate many diseasesassociated with oxidative stress.
