The role of thiol-disulfide homeostasis and ischemia-modified albumin in osteosarcopenia.

BACKGROUND: Oxidative stress results from an imbalance between the induction of reactive oxygen species and the ability of cells to metabolize them. Numerous markers can be used to assess the level of oxidative stress. Thiol-disulfide homeostasis (TDH) and ischemia-modified albumin (IMA) are some of them. The aim of this study is to investigate the role of TDH and IMA, which are indicators of oxidative stress, in older patients with osteosarcopenia (OS). METHODS: The study was conducted cross-sectionally in a geriatrics outpatient clinic. Patients who applied to the outpatient clinic for three months were included in the study. Patients with acute infection, delirium, malignancy, severe liver, heart or kidney dysfunction and who did not give their consent for the study were excluded from the study. The study was conducted with 136 patients. Sarcopenia was diagnosed according to muscle ultrasonography (USG) and handgrip strength (HGS) results. Osteopenia/osteoporosis was diagnosed according to bone mineral densitometry (BMD) results. The combination of osteopenia/osteoporosis and sarcopenia was accepted as OS. RESULTS: Native thiol, total thiol value and nativethiol /totalthiol*100 values were significantly lower in the group with OS (respectively; value = 265 ± 53.8 standard deviation (SD) µmol/L, p = ≤ 0.001; value = 295.33 ± 55.77 SD µmol/L, p = 0.001; value = 90.06 (2.8) interquartile ranges (IQR), p = 0.033). Disulfide/native thiol*100 and disulfide/total thiol*100 values were significantly higher in the group with OS (respectively; value = 5.5 (1.7) IQR, p = 0.033; value = 4.97 (1.4) IQR, p = 0.034). CONCLUSION: In our study, the role of oxidative stress in OS was demonstrated by using TDH as an oxidative stress parameter.

The thiol/disulfide balance is shifted towards oxidation in psoriatic arthritis compared to controls and is associated with higher disease activity.

OBJECTIVE: This study was designed to compare thiol/disulfide and ischemia-modified albumin (IMA) levels between psoriatic arthritis (PsA) and healthy controls and evaluate the correlation between these molecules and the disease activity scores used in PsA. METHODS: A total of 63 PsA patients and 49 healthy volunteers were included in the study. Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), modified disease activity score 28 (DAS28), and Bath Ankylosing Spondylitis Functional Index (BASFI) scores were used as disease activity indices for PsA patients. Calculations of native thiol (-SH), disulfide (-SS), and total thiol (-SH+-SS) molecules were made by the automatic spectrophotometric method, and the albumin cobalt binding test was used to measure IMA levels. RESULTS: In the PsA group, -SS/-SH and -SS/(-SH+-SS) levels were higher and -SH/(-SH+-SS) levels were lower than in controls. In the linear regression analysis, a significant correlation relationship was detected between DAS28-erythrocyte sedimentation rate (ESR) and -SS/(-SH+-SS) (ß = 0.795, CI 95%, 0.196-1.395; P = .010), -SH/(-SH+-SS) (ß = -0.475, CI 95%, 0.114-0.836; P = .010) and IMA (ß = 3.932, CI 95%, 0.859-7.005; P = .013). Additionally, a significant correlation was detected between IMA and BASDAI and BASFI. CONCLUSION: In PsA, thiol/disulfide homeostasis has shifted in favor of disulfide as an oxidative indicator. Serum thiol/disulfide levels are correlated with PsA disease activity indices.

Serum netrin-1 levels are high in Rheumatoid arthritis associated interstitial lung disease.

BACKGROUND: Recent data show that netrin-1 has a role in development of pulmonary fibrosis. This study was aimed to investigate serum netrin-1 level and its relation to interstitial lung disease(ILD) in patients with rheumatoid arthritis (RA). METHOD: 42 RA patients with RA-ILD, 58 RA patients without RA-ILD (RA non-ILD group), and 61 healthy volunteers were included in this study. The modified DAS28-ESR score was used to calculate disease activity in RA patients. Using the quantitative immunoassay method, Serum netrin-1 levels were measured with an ELISA kit (Catalog number: E-EL-H2328; lab science, lot number: GZWTKZ5SWK, Texas, USA). RESULTS: The median value of netrin-1 was found to be significantly higher in the RA-ILD group (82.9 [59.9-124]) compared to both the RA non-ILD group(52.9 [49.5-73.1])(B = -0.006, OR = 0.994, CI 95 %=0.989-0.999, P = 0.018) and the control group(53.5 [49.5-87.5]) (B: -0.005, OR: 0.994, CI 95 %: 0.990-0.999, p: 0.022). A cut-off value of 61.78 for netrin-1 was found to have a sensitivity of 73.8 % and a specificity of 69 % for the diagnosis of RA-ILD (AUC [95 %Cl] = 0.771 [0.679-0.862], p < 0.0001).It was found that high serum netrin-1 level was strongly associated with the RA-usual interstitial pneumonia(UIP) pattern and poorly related to the RA-nonspecific interstitial pneumonia(NSIP) pattern compared to the RA non-ILD group. CONCLUSIONS: Netrin-1 is elevated in the serum of patients with RA-ILD, especially in the UIP pattern. Netrin-1 may be a potential candidate for predicting the development of RA-ILD that should be investigated in the pathophysiological and therapeutic fields.

The effect of slow-release vaginal dinoprostone on maternal and fetal oxidative stress in term pregnancies complicated by oligohydramnios: Prospective cohort study.

BACKGROUND: To evaluate changes in oxidant status using thiol/disulfide homeostasis in mothers and fetuses after induction of labor with slow-release vaginal dinoprostone inserts. METHODS: A total of 70 pregnant women were divided into two groups. Thirty-five women in whom labor was induced with slow-release vaginal dinoprostone inserts (10 mg of prostaglandin E2, group A) were compared before and after the administration. The other 35 women, who were followed up spontaneously during labor (group B), were included as a control group. Both groups were diagnosed with isolated oligohydramnios without signs of placental insufficiency. The thiol/disulfide homeostasis parameters were calculated before medical induction and after removal of the insert at the beginning of the active phase of labor. Maternal and cord blood values were measured in both groups. RESULTS: Although the balance shifted to the antioxidant side after the slow-release vaginal dinoprostone insert was applied, there was no significant difference in maternal oxidative load compared to the pre-application status (5.32 ± 014/5.16 ± 0.15, p = 0.491). Despite the shift toward the antioxidant side, maternal antioxidants were still significantly lower in the group that received slow-release vaginal dinoprostone at the beginning of the active phase of labor than in the control group (295.98 ± 13.03/346.47 ± 12.04, respectively, p = 0.009). There was no statistically significant difference in terms of oxidative balance or newborn Apgar score ( p > 0.05). CONCLUSION: Induction of labor with slow-release vaginal dinoprostone inserts in pregnancies with isolated oligohydramnios does not cause further oxidative stress and is safe for both mothers and neonates in terms of oxidant load by thiol/disulfide homeostasis.

Relationship between pattern reversal visual evoked potential P100 wave latency and dysfunctional HDL in patients with multiple sclerosis subjected to an optic neuritis attack: A case-control study.

Optic neuritis frequently occurs during the clinical course of multiple sclerosis (MS). In this condition, demyelination of the optic nerve occurs, which electrophysiologically causes a delay in P100 wave latency. Sensitive cholesterol homeostasis is critical for the formation of the myelin sheath and for myelin to become functionally mature. High-density lipoprotein (HDL) becomes dysfunctional under oxidative stress and plays an important role in the pathogenesis of MS. In this study, HDL levels of MS patients suffering from optic neuritis were compared with those of healthy individuals, and the relationship between pattern reversal visual evoked potential (PRVEP) P100 wave latency and HDL levels in patients with optic neuritis attacks was analyzed. PRVEP studies were performed in patients with MS who had an episode of optic neuritis, and P100 wave latencies were measured. Peripheral blood samples were collected from healthy participants and patients. Lipid levels and myeloperoxidase (MPO) and paraoxonase (PON) activities were measured, and the MPO/PON ratio was then calculated. The lipid profiles and dysfunctional HDL levels in the healthy and patient groups were compared. Finally, the relationship between these parameters and the PRVEP-P100 wave latency was examined. Total cholesterol and low-density lipoprotein (LDL) levels were significantly higher in the patient group (P = .044; P = .038, respectively). There was no statistically significant difference in HDL levels between groups (P = .659). The distribution of MPO values was similar between groups (P = .452). PON values were significantly lower, whereas the MPO/PON ratios were significantly higher in the patient group than in the control group (P = .025; P = .028, respectively). A statistically significant positive correlation was found between the elevated MPO/PON ratio, representing dysfunctional HDL, and both the mean and maximum PRVEP-P100 wave latencies (P < .001, R = 0.690; P < .001, R = 0.815, respectively). A dysfunctional form of HDL may lead to poor deactivation of remyelination-limiting factors and may ultimately be associated with poor outcomes in optic neuritis.

Evaluation of maternal serum thiol and ischemia-modified albumin levels in cases of placenta previa: A case-control study in a tertiary center.

AIM: We aim to compare the maternal serum thiol and ischemia-modified albumin (IMA) levels between pregnant women with placenta previa and those with uncomplicated pregnancies and to determine whether changes in these levels were useful in predicting cases of abnormally invasive placenta (AIP). METHODS: Fifty-five pregnant women diagnosed with placenta previa according to the diagnostic criteria (case group) were compared to 100 women with uncomplicated pregnancies of similar demographic characteristics (control group). The patients with placenta previa were further divided into two subgroups: AIP (n = 20) and placenta previa without invasion (n = 35). The maternal serum native thiol, total thiol, disulfide, and IMA levels of the groups were evaluated. RESULTS: The native thiol, total thiol, and IMA values were significantly lower in the case group than in the control group (p < 0.001). The disulfide values were similar between the study and control groups (p = 0.488). When the AIP and placenta previa without invasion groups were compared, the levels of native thiol, total thiol, disulfide, and IMA were similar (p > 0.05). CONCLUSIONS: Maternal serum thiol and IMA levels were lower in placenta previa cases compared to the control group. However, these parameters were not useful in predicting AIP cases.

Physical frailty is related to oxidative stress through thiol/disulfide homeostasis parameters.

AIM: To evaluate relationship between frailty and oxidative stress through thiol/disulfide homeostasis parameters [Native thiol (NT), total thiol (TT), and disulfide levels (D), disulfide-native thiol (D/NT), disulfide-total thiol (D/TT), native thiol-total thiol (NT/TT) ratios, and ischemia-modified albumin levels (IMA)]. MATERIALS AND METHODS: In total, 139 community-dwelling older adults were included. The frailty status, defined by the FRIED frailty index (FFI) and Clinical Frailty Scale (CFS), and comprehensive geriatric assessment results compared with thiol/disulfide homeostasis parameters and ischemia-modified albumin levels. RESULTS: NT and TT levels were significantly lower in the frail group (respectively; p = 0.014, p = 0.020). The FFI scores were correlated with the levels of NT, TT, D/NT, D/TT, and NT/TT (respectively; r = - 0.25, r = - 0.24, r = 0.17, r = 0.17, r = - 0.17). The significant correlation could not be retained with the CFS scores. In ROC analysis, the AUC for NT was calculated as 0.639 in diagnosing frailty according to the FFI (95% CI 0.542-0.737), AUC was 0.638 for TT (95% CI 0.540-0.735), and AUC was 0.610 for NT/TT (95% CI 0.511-0.780). The AUC was calculated as 0.610 for both D/NT and D/TT in diagnosing physical frailty (95% CI 0.511-0.708). CONCLUSION: Thiol/disulfide homeostasis parameters can be a potential biomarker in diagnosing physical frailty. However, further studies are needed for diagnosing frailty defined with cumulative deficit models.

Thiol-disulphide Homeostasis in Patients with Schizophrenia: The Potential Biomarkers of Oxidative Stress in Acute Exacerbation of Schizophrenia.

Objective: : Recent evidence suggests that oxidative stress contributes to the pathophysiology of schizophrenia. This study aimed to compare thiol-disulphide homeostasis in acute and stable phases of schizophrenia for the first time. Methods: : Among the patients with schizophrenia, 61 in the acute-phase and 61 in the stable phase of their illness were enrolled in the study. Native thiol (NT), total thiol (TT), disulphide (SS), disulphide/native thiol, disulphide/total thiol, and native thiol/total thiol for thiol-disulphide homeostasis were compared between the groups. The Brief Psychiatric Rating Scale (BPRS), Scale for the Assessment of Positive/Negative Symptoms (SAPS/SANS), Clinical Global Impression-Severity Scale (CGI-S), Barnes Akathisia Rating Scale, and Simpson-Angus Scale were used to assess symptoms. Results: : After controlling for age, sex, body mass index, and smoking status there were significant differences in NT, TT, SS/NT, SS/TT, and NT/TT, but not SS. Thiol/disulphide homeostasis has shifted in favour of the oxidative side in patients with acute-phase compared to that in stable schizophrenia. BPRS, SAPS, and CGI-S scores were significantly correlated with all six thiol-disulphide parameters, but not SANS, when controlling for age and sex. Significant receiver operating characteristic (ROC) curves were obtained for all thiol-disulphide homeostasis parameters. Discriminant analysis was found to be statistically significant in discriminating between groups. Conclusion: : These results show that oxidative status increases thiol-disulphide homeostasis in patients with acute-phase schizophrenia compared to those with stable schizophrenia. These findings suggest that thiol-disulphide parameters can be used as biomarkers for the acute exacerbation of schizophrenia.

Effect of ACTH Stimulation on Ischemia-Modified Albumin Levels in vivo.

Objective: Ischemia-modified albumin (IMA) formation is associated with increased reactive oxygen species (ROS) production, while cortisol leads to decreased ROS levels. We aimed to evaluate the effect of ACTH stimulation on IMA levels and whether the effect is dose-dependent or not. Methods: A total of 99 subjects with normal ACTH test results were included in the study, where 80 subjects were performed to standard-dose ACTH test while 19 subjects were performed to low-dose ACTH test. Blood samples were collected to determine cortisol and IMA levels; at minutes 0, 30, and 60 following the standard-dose ACTH test and at minutes 0 and 30 following the low-dose ACTH test. Results: IMA levels decreased significantly within 30 minutes and the decrease continued up to 60th minutes (p:0.002) after standard-dose ACTH stimulation. After ACTH stimulation, a weak negative correlation was found between peak cortisol and IMA levels at the 30th minute (r:0.233 p:0.02). There was no significant difference in IMA levels after low-dose ACTH stimulation, despite providing an increase in cortisol (p:0.161). Conclusion: IMA levels decrease rapidly after standard-dose ACTH stimulation, while a decrease in IMA levels is not observed after low-dose ACTH stimulation. The lack of decrease in IMA levels after low-dose ACTH stimulation suggests a possible dose-dependent relationship between ACTH and IMA. The moderate increase in cortisol with no reduction in IMA levels after low-dose ACTH stimulation and the weak correlation between peak cortisol and 30th-minute IMA levels after standard-dose ACTH stimulation suggest that ACTH may have a direct effect on IMA.

Are Thiols Useful Biomarkers for Coronary Collateral Circulation in Patients with Stable Coronary Artery Disease?

Our aim was to investigate the relationship between thiol, which is the main component of the antioxidant system, and coronary collateral circulation (CCC). Our patients consisted of people with stable coronary artery disease (sCAD) and total occlusion in at least one vessel (n = 249). We divided the patients into two groups, good and poor, according to their CCC degree. We determined that DM, total thiol, and disulfide are independent predictors of poor CCC in multivariate logistic regression analysis (OR: 1.012, 95% CI: 1.008-1.017, p < 0.001; OR: 1.022, 95% CI: 1.000-1.044, p = 0.044; OR: 2.671, 95% CI: 1.238-5.761, p = 0.012, respectively). The ROC analysis showed a cut-off value of 328.7 for native thiol regarding the prediction of poor CCC, with 67.4% specificity and 78% sensitivity. For disulfide, it revealed a cut-off value of 15.1 regarding the prediction of poor CCC, with 57.9% specificity and 69.5% sensitivity. In this study, we detected that the patients with sCAD who developed poor CCC had lower levels of native thiol, total thiol, and disulfide compared to those with good CCC. The most interesting finding of our study is that CCC formation is an effective predictor of the antioxidant cascade rather than the inflammation cascade in sCAD patients.

Can Blood Biomarkers Be Used to Assess Oxidative Stress in COPD Patients After Pulmonary Rehabilitation.

Purpose: To determine the level of oxidative stress in the body due to pulmonary rehabilitation (PR) with thiols and disulfide and to investigate their relationship with indirect markers such as creatine kinase (CK), creatine kinase - MB (CK-MB), and lactate dehydrogenase (LDH), which show cell destruction. Patients and Methods: Patients with chronic obstructive pulmonary disease (COPD) are included in inpatient and outpatient care. They were evaluated before and after for PR, and an exercise program was prescribed. In addition, native thiol (NT), total thiol (TT), disulfide (DS), LDH, CK, and CK-MB values were tested. Results: The mean age of 21 patients was 63±7.31 years. Eleven of them were outpatients and 10 of them were inpatients. Most of the patients were male (M/F=20/1, 95.2/4.8%). There was a significant difference in pulmonary function tests (PFT), St. George Respiratory Questionnaire (SGRQ), and 1 repetition maximum (1RM) before and after the treatment (p<0.001). There was a correlation between PFT and 1RM upper extremity. While there was no significant difference between thiols and disulfide, according to GOLD scores, there was a significant difference in patients with level 3-MMRC. No correlation was found between LDH, CK, CK-MB, and thiols, DS. ΔCK was found to be associated with ΔDS, and ΔCK-MB with ΔNT, and ΔTT. Conclusion: PR contributes to the antioxidant process by improving respiration and reducing oxidative stress. The decrease in LDH, CK with PR, increase in CK-MB, and correlation of CK with thiols and DS gave a different interpretation. In this case, it should be considered that oxidative stress may also be increased in people with high CK values.

Research of Importance of Thiol, CRP and Lactate in Diagnosing Mesenteric Ischemia At An Early Stage: Animal Model.

INTRODUCTION AND PURPOSE: Acute mesenteric ischemia is especially seen in the elderly population. It has an increasing incidence in today's world where the average life expectancy is increasing. Early diagnosis is the most important factor reducing morbidity and mortality, and there is still no marker with high sensitivity and specificity for early diagnosis.In this study, we aimed to find a more sensitive and specific serum marker in the early diagnosis of mesenteric ischemia by comparing thiol with the currently used markers C-reactive protein and lactate. MATERIALS AND METHODS: In our study, 32 Wistar Albino male rats, 10-12 weeks old, weighing 250-300 g, were used. 32 rats were divided into 4 groups, one of which was the control group. The superior mesenteric artery of the other 3 groups was ligated. Blood samples were taken after 2 hours from the first group, 4 hours from the second group, and 6 hours from the third group. Then the rats were sacrificed. Mesenteric ischemia and its level were observed in sacrificed subjects. The samples were separated under appropriate conditions and analyzed biochemically. RESULTS: As the ischemia time increased, CRP increased and this increase was found to be statistically insignificant (p>0.05). The changes in lactate were found to be statistically significant (p<0.05). The difference between the changes of total and native thiol values was found to be statistically significant (p<0.05). CONCLUSION: Although CRP is a non-specific parameter in the early diagnosis of acute mesenteric ischemia, lactate maintains its importance as seen in our study. Differences in total thiol and native thiol changes were statistically significant. The fact that this significant difference is observed at the 4th hour values, reveals the importance of these parameters in early diagnosis. Thanks to the economic and fast results of thiol parameters, it is thought that new studies to be added to the literature can lead to the diagnosis of mesenteric ischemia.

Evaluation of ischemia-modified albumin in the diagnosis and the clinical severity of COVID-19 in children.

BACKGROUND: There is no specific biomarker used in the diagnosis of COVID-19 and predicting its clinical severity. This study aimed to investigate the utility of ischemia-modified albumin (IMA) in diagnosing and predicting clinical severity in children with COVID-19. METHODS: Between October 2020 and March 2021, 41 cases constituted the COVID-19 group and 41 cases constituted the healthy control group. IMA levels were measured at admission (IMA-1) and 48-72 hours (IMA- 2) in the COVID-19 group. In the control group, it was measured at admission. COVID-19 clinical severity was classified as asymptomatic infection, mild, moderate, severe, or critical disease. Patients were divided into two groups (asymptomatic/mild and moderate/severe) to evaluate IMA levels in terms of clinical severity. RESULTS: In the COVID-19 group, the mean IMA-1 level was 0.901±0.099, and the mean IMA-2 level was 0.866±0.090. The mean level of IMA-1 in the control group was 0.787±0.051. When IMA-1 levels of COVID-19 and control cases were compared, the difference was statistically significant (p < 0.001). When clinical severity and laboratory data are compared, C-reactive protein, ferritin and ischemia-modified albumin ratio (IMAR) were statistically significantly higher in moderate-severe clinical cases (p=0.034, p=0.034, p=0.037 respectively). However, IMA-1 and IMA-2 levels were similar between the groups (p=0.134, p=0.922, respectively). CONCLUSIONS: To date, no study has been conducted on IMA levels in children with COVID-19. The IMA level may be a new marker for the diagnosis of COVID-19 in children. Studies with a larger number of cases are needed to predict clinical severity.

Thiol-disulphide homeostasis, ischemia-modified albumin, complete blood count-derived inflammatory markers and C-reactive protein from acute mania to early remission in bipolar disorder.

OBJECTIVES: There is much recent evidence that inflammation contributes to the pathophysiology of acute mania in bipolar disorder (BD). However, no study was evaluated in which the change in thiol-disulphide homeostasis, ischemia-modified albumin (IMA), complete blood count-derived inflammatory markers (CBC-IMs) and C-reactive protein (CRP) levels in bipolar patients was followed-up from acute mania to early remission. METHODS: Seventy-seven bipolar patients in acute mania and ninety-one HC were enrolled. We measured levels of thiol-disulphide parameters, IMA, and CBC-IMs such as neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), red-cell-distribution-width (RDW)-to-platelet ratio (RPR), systemic immune-inflammatory index (SII), and systemic inflammatory response index (SIRI), CRP and platelet-to-albumin ratio (PAR), after adjusting for age, gender, body-mass index (BMI) and smoking status, during acute mania to subsequent early remission. The results were compared with HC. RESULTS: The levels or ratios of all thiol-disulphide parameters except for disulphide, IMA and CRP of bipolar patients in both acute mania and early remission were significantly different from HC, after adjusting for confounders. The NLR, SII, CRP and PAR values of bipolar patients were significantly higher in only acute mania compared to HC. Significant changes in thiol-disulphide parameters and IMA levels were not found in early remission after acute mania. LIMITATIONS: Short follow-up period and lack of drug-naive patients. CONCLUSIONS: Our results suggest that thiol-disulphide parameters, IMA level and SIRI value might be a trait biomarkers of inflammation in BD. In addition, NLR, SII and PAR values and CRP level might be a state biomarker of inflammation in bipolar patients in a manic phase.

Oxidative Stress and Inflammatory Biomarkers in People with Methamphetamine Use Disorder.

Objective: This study aimed to investigate the blood serum levels of biomarkers specifying oxidative stress status and systemic inflammation between people using methamphetamine (METH) and the control group (CG). Serum thiol/disulfide balance and ischemia-modified albumin levels were studied to determine oxidative stress, and serum interleukin-6 (IL-6) levels and complete blood count (CBC) were to assess inflammation. Methods: Fifty patients with METH use disorder (MUD) and 36 CG participants were included in the study. Two tubes of venous blood samples were taken to measure oxidative stress, serum thiol/disulfide balance, ischemia-modified albumin, and IL-6 levels between groups. The correlation of parameters measuring oxidative stress and inflammation between groups with sociodemographic data was investigated. Results: In this study, serum total thiol, free thiol levels, disulfide/native thiol percentage ratios, and serum ischemia- modified albumin levels of the patients were statistically significantly higher than the healthy controls. No difference was observed between the groups in serum disulfide levels and serum IL-6 levels. Considering the regression analysis, only the duration of substance use was a statistically significant factor in explaining serum IL-6 levels. The parameters showing inflammation in the CBC were significantly higher in the patients than in the CG. Conclusion: CBC can be used to evaluate systemic inflammation in patients with MUD. Parameters measuring thiol/disulfide homeostasis and ischemia-modified albumin can be, also, used to assess oxidative stress.

Thiol/Disulfide Homeostasis and Ischemia-Modified Albumin Levels in 61 Patients with Hypercapnia: A Case-Control Study.

BACKGROUND Hypercapnia is abnormally high arterial partial pressure of carbon dioxide (CO2). CO2 can affect redox signaling mechanisms, leading to production of oxidative derivatives. Thiol is formed by attaching a sulfhydryl group to a carbon atom. Under oxidative stress, it forms covalent bonds called thiol disulphide bonds. Serum albumin is modified to ischemia-modified albumin (IMA) by exposure to free radicals. This case-control study aimed to evaluate thiol/disulphide homeostasis and IMA levels in 61 patients with hypercapnia. MATERIAL AND METHODS We studied 61 patients with hypercapnia and 61 normocapnic volunteers in the control group, between May 2018 and January 2019; 56 of these patients were diagnosed with chronic obstructive pulmonary disease and 5 of them were diagnosed with obstructive sleep apnea syndrome. Arterial blood samples analyzed by using the Ellman reagent for thiol/disulphide data. A colorometric assay was used for detection of IMA levels. RESULTS Native thiol and total thiol values in the hypercapnic group were significantly lower than in the control group (P=0.024, P=0.006 respectively), as IMA values were significantly higher (P<0.001). There was no statistically significant difference between the hypercapnic and control groups in terms of disulphide, disulphide/native thiol, disulphide/total thiol, and native thiol/total thiol values (P>0.05). CONCLUSIONS In hypercapnic patients, there are changes in thiol/disulphide homeostasis and IMA levels. All significant differences in this study support that changes in thiol disulphide homeostasis and IMA in hypercapnic patients are indicators of oxidative stress.

A New Perspective for Potential Organ Damage Due to Iron-Mediated Oxidation in Thalassemia Major Patients.

BACKGROUND: The aim of this study is to develop new perspectives to prevent or reduce potential organ damage due to iron-mediated oxidation in thalassemia major patients. METHODS: Seventy patients were included in this study. Blood samples were taken from the patients before and after transfusion. Total thiol, native thiol, disulfide, disulfide/native thiol percentage ratio, ischemia modified albumin (IMA), total antioxidant status (TAS), total oxidant status (TOS), and ferroxidase levels were determined. Additionally, undepleted thiol level (UTL) was determined as a new parameter associated with organ damage. RESULTS: After transfusion, the levels of native thiol, total thiol, disulfide, TAS, ferroxidase, and TOS were higher, while the IMA levels and disulfide/native thiol percent ratio were lower. Significant correlations were found between antioxidant and oxidant tests before and after transfusion. Additionally, a negative correlation was found between the TOS and UTL levels of the patients measured before the transfusion. CONCLUSION: In the present study, transfusion therapy increased both oxidation and the antioxidant levels. In addition, the term UTL has been introduced as a parameter that enables the determination of the oxidation level that may cause potential organ damage in transfusion-dependent thalassemia patients.

Evaluation of Thiol-Disulfide Homeostasis with Electrical Status Epilepticus in Slow Sleep (ESES).

Background: Electrical status epilepticus in sleep (ESES) is an epileptic syndrome specific to childhood and has a broad clinical spectrum that included seizures, behavioral/cognitive impairments, and motor neurological symptoms. Antioxidants are seen as promising neuroprotective strategies for the epileptic state by combating the harmful effects of excessive oxidant formation in mitochondria. Objective: This study aims to evaluate the thiol-disulfide balance and to determine whether it can be used in the clinical and electrophysiological follow-up of patients with ESES, especially in addition to the electroencephalography (EEG) examination. Methods: The study included 30 patients, aged 2-18 years and diagnosed with ESES in the Pediatric Neurology Clinic of the Training and Research Hospital and a control group of 30 healthy children. Total thiol, native thiol, disulfide, and ischemia-modified albumin (IMA) levels were measured, and disulfide-thiol ratios were calculated for both groups. Results: Native thiol and total thiol levels were significantly lower and IMA level and disulfide-native thiol percentage ratio were significantly higher in the ESES patient group than in the control group. Conclusion: Serum thiol-disulfide homeostasis is an accurate marker of oxidative stress in ESES, and standard and automated measures of thiol-disulfide balance as an indicator of oxidative stress showed a shift toward oxidation in ESES patients in this study. The negative correlation between spike-wave index (SWI) and thiol levels, and serum thiol-disulfide levels suggest that they can be used as biomarkers for follow-up of patients with ESES in addition to EEG. IMA can also be used for long-term response to monitoring purposes at ESES.

Serum and Follicular Fluid Thiol/Disulfide Homeostasis in Diminished Ovarian Reserve Patients Undergoing In Vitro Fertilization/Intracytoplasmic Sperm Injection Treatment.

INTRODUCTION: The etiologies of diminished ovarian reserve (DOR) are still poorly understood, and many factors such as age, autoimmunity, genetics, idiopathicity, iatrogenesis, and oxidative stress (OS) play a role. Oxidative cellular damage increases following reactive oxygen species (ROS)-induced aging. This is the first study to evaluate the serum and follicular fluid (FF) thiol/disulfide homeostasis in patients under 35 years of age with DOR undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI). METHODS: In this study, DOR was defined by the Poseidon criteria, and Poseidon group 3 women were selected as the study group (n = 40). The control group was composed of patients with the diagnosis of mild-moderate male factor infertility (n = 30). RESULTS: The FF and serum native and total thiol levels, the markers of the antioxidant system, were significantly decreased in the DOR group compared with the control group (p = 0.021) (p = 0.037) (p = 0.029) (p = 0.04). On the other hand, we found no significant differences in the oxidant parameters between the groups (p > 0.05). CONCLUSIONS: An intrinsic deficiency of antioxidants can play an important role in the etiology of DOR. The dietary addition of antioxidants could be beneficial in DOR patients.

The Role of Ischemia-modified Albumin and Ischemia-Modified Albumin to Albumin Ratios in Patients with Alopecia Areata.

INTRODUCTION: OBJECTIVE: To investigate the role of ischemia-modified albumin (IMA) and IMA/albumin levels in patients with AA. METHODS: The present prospective crossectional study includes patients ≥18 who were admitted to the Dermatology and Venerology Department of Hitit University Hospital between April 1, 2021, and September 30, 2021. 70 patients participated in the study (n=34 for the study group and n=36 for the control group). Demographic features, clinical characteristics, IMA, and IMA/albumin levels were compared between the groups. The study group was divided into subgroups based on the number of patches, disease duration, and the number of disease attacks. IMA and IMA/albumin levels were compared between each subgroup. RESULTS: The study and control groups were similar with regard to demographic features and clinical characteristics. Significant differences were observed between the mean IMA and IMA/albumin ratio (p=0.004 and 0.012, respectively). The study subgroups were comparable in the number of patches, disease duration, and number of disease attacks. CONCLUSION: Although oxidative stress is an important component in the etiology of AA, IMA and IMA/albumin may not be useful in the prediction of disease severity in patients with AA.