Did diet compliance and remission reduce oxidative stress in celiac patients?

OBJECTIVE: We aimed to examine the effect of remission status on thiol-disulfide homeostasis in celiac patients and thus to indirectly determine the effect of oxidative stress and inflammation caused by non-compliance with the diet. METHODS: Between February 2019 and December 2021, 117 patients diagnosed with celiac disease were included in this prospective randomized and controlled study. In addition to routine tests of celiac patients, thiol and disulfide measurements were made from the blood both at the beginning of the study and at the end of the first year. RESULTS: While 52 of the patients (44.4%) were in remission, 65 patients (55.6%) were not. There was an evident increase in native thiol levels of the patients who were initially not in remission but went into at the end of the first year (347.4±46.7 µmol/L vs. 365.3±44.0 µmol/L; p=0.001). Mean plasma disulfide levels of patients with celiac going into remission became reduced in the first year from the level of 14.5±5.1 µmol/L down to 8.9±4.2 µmol/L (p<0.001). In celiac patients who entered remission, disulfide and anti-tissue transglutaminase immunoglobulin A levels decreased in a correlation (r=0.526; p<0.001). CONCLUSION: Not being in remission in celiac disease leads to increased oxidative stress, and thiol-disulfide homeostasis is an indirect indicator of this. Additionally, providing remission in celiac patients reduces oxidative stress.

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.

An Evaluation of Oxidative Stress With Thiol/Disulfide Homeostasis in Patients With Persistent Allergic Rhinitis.

BACKGROUND: We evaluated the efficacy of medical treatment on thiol-disulfide balance despite ongoing allergic stimulation. METHODS: The research design was a prospective observational study that included 35 persistent allergic rhinitis (AR) patients. All patients who were diagnosed with persistent AR were included. A skin prick test was applied to all patients, and the Sino-nasal Outcome Test-22 was used to evaluate sinonasal symptoms. Thiol/disulfide homeostasis balance parameters were measured using a novel automatic and spectrophotometric method and compared statistically. Serum total thiol (TT), native thiol (SH), disulphide (SS), disulphide/native thiol (SS/SH), disulphide/total thiol (SS/TT), and native thiol/total thiol (SH/TT) ratios were measured after the second month of the treatment. RESULTS: The 35 patients included 20 (58%) females and 15 (42%) males. The mean age of the patients was 33.17 ± 9.9 years. Disulphide, SS/SH, and SS/TT ratios decreased significantly after the treatment (P < .05), while SH and SH/TT increased significantly (P < .05). The mean SH measurement increased significantly in the second month (P = .001), but TT mean measurements showed no difference after the treatment (P = .058). The mean SS measurements, on the other hand, decreased significantly in the second month (P = .003). CONCLUSION: Thiol/disulfide homeostasis may be used as a marker to evaluate the efficacy of persistent AR treatments. After the treatment, the increase in SH levels suggested the decrease in oxidative stress, even though allergen exposure continued.

Evaluation of IL-10, IFN-γ, and thiol-disulfide homeostasis in patients with drug-resistant epilepsy.

AIM: This study compared dynamic thiol-disulfide homeostasis (an oxidative stress marker), anti-inflammatory interleukin-10 (IL-10) levels, and proinflammatory interferon gamma (IFN-γ) levels in drug-resistant epilepsy patients with those in patients with well-controlled epilepsy and healthy controls. METHOD: This prospective cross-sectional study enrolled 89 people: 27 with drug-resistant epilepsy, 30 with well-controlled epilepsy, and 32 healthy controls matched in demographic characteristics. RESULTS: The mean serum IL-10 levels were significantly lower and the mean serum IFN-γ levels significantly higher in the drug-resistant epilepsy patients compared to the well-controlled epilepsy and healthy control groups. The mean serum native thiol (SH) and total thiol (TT) levels were significantly lower, and the disulfide (SS) levels were significantly higher in the drug-resistant group than in the other two groups. CONCLUSIONS: The significant differences in thiol-disulfide homeostasis and IL-10 and IFN-γ levels in the drug-resistant epilepsy group suggest that these markers indicate a poor prognosis in epilepsy.

Dynamic thiol/disulphide homeostasis and ischemic modified albumin levels in isolated oligohydramnios.

OBJECTIVE: Oligohydramnios is defined as amniotic fluid index in ultrasonographic measurement is less than 5 percentile according to gestational age, the amniotic fluid volume is ≤ 5 cm, or if the single deepest dial is < 2 cm. The condition of oligohydramnios that not with fetal structural/chromosomal abnormalities, intrauterine growth retardation, intrauterine infection and maternal disease is described as isolated oligohydramnios (IO). The aim of this study is to examine whether oxidative stress and reactive oxygen species (ROS) have a place in the pathophysiology of IO. MATERIALS AND METHODS: In this prospective case-control study, a total of 126 participants were included. The patient group consisted of 65 patients who were diagnosed IO, and the control group consisted of 61 healthy normal pregnants. Native thiol (-SH), total thiol (-SH + -SS), dynamic disulfide (-SS), IMA values from maternal serum were measured and compared between groups. RESULTS: Maternal serum -SH and -SH + -SS values were significantly lower in the IO group than in the control group (409.47 ± 55.36 µmol/L vs. 437.40 ± 48.68 µmol/L, p = 0.03 and 457.40 ± 63.01 µmol/L vs. 484.59 ± 52.75 µmol/L, p = 0.01). In the IO group when -SS/-SH and -SS/-SH + -SS ratio was found to be statistically significantly higher than control group (5.84 ± 1.1 vs 5.41 ± 0.71, p = 0.01 and 5.2 ± 0.88 vs 4.8 ± 0.58, p = 0.01), -SH/-SH + -SS ratio was significantly lower (89.56 ± 1.7 vs 90.24 ± 1.16, p = 0.01). There was no significant difference in terms of -SS value (p = 0.66). IMA value was significantly higher in the IO group than control group (0.76 ± 0.10 ABSU vs 0.68 ± 0.06, p < 0.01). It is seen as a result of ROC analysis that -SH, -SH + -SS, -SS/-SH, -SS/-SH + -SS, -SH/-SH + -SS and IMA values have a diagnostic value for IO (p < 0.05). CONCLUSION: The thiol/disulfide balance shifted towards oxidative stress in IO compared to control group. So oxidative stress and ROS have a place in the pathophysiology of IO.

Alteration of serum biomarkers in patients with hypertrophic cardiomyopathy with and without atrial fibrillation.

Aim: We sought to determine the relationship between presence of atrial fibrillation (AF) and serum biomarkers, including native thiol (antioxidant), disulphide/native thiol ratio, Hs-CRP and high-sensitivity Troponin-I (Hs-TnI) in hypertrophic cardiomyopathy (HCM). Materials & methods: We enrolled consecutive 121 HCM outpatients without AF and 40 HCM outpatients with AF. A 12-lead electrocardiogram, transthoracic echocardiography and 24/48-h ambulatory rhythm monitoring were performed for all patients. Fasting venous blood samples were taken from all study patients to measure serum thiol-disulphide homeostasis, Hs-CRP and Hs-TnI. Results: Serum-native thiol was lower and disulphide/native thiol ratio was more oxidized in HCM patients with AF (p < 0.001). Also, HCM patients with AF had higher Hs-TnI and Hs-CRP than no-AF HCM patients. Disulphide/native thiol ratio, serum-native thiol, age, NYHA functional class≥III, and advanced diastolic dysfunction were independently associated with the presence of AF in HCM. Conclusion: In addition to clinical and echocardiographic findings, oxidative stress is also associated with AF in HCM patients.

Effects of antiviral drug therapy on dynamic thiol/disulphide homeostasis and nitric oxide levels in COVID-19 patients.

The novel coronavirus disease 2019 (COVID-19) has led to a serious global pandemic. Although an oxidative stress imbalance occurs in COVID-19 patients, the contributions of thiol/disulphide homeostasis and nitric oxide (NO) generation to the pathogenesis of COVID-19 have been poorly identified. Therefore, the aim of this study was to evaluate the effects of antiviral drug therapy on the serum dynamics of thiol/disulphide homeostasis and NO levels in COVID-19 patients. A total of 50 adult patients with COVID-19 and 43 sex-matched healthy control subjects were enrolled in this prospective study. Venous blood samples were collected immediately on admission to the hospital within 24 h after the diagnosis (pre-treatment) and at the 15th day of drug therapy (post-treatment). Serum native thiol and total thiol levels were measured, and the amounts of dynamic disulphide bonds and related ratios were calculated. The average pre-treatment total and native thiol levels were significantly lower than the post-treatment values (P < 0.001 for all). We observed no significant changes in disulphide levels or disulphide/total thiol, disulphide/native thiol, or native thiol/total thiol ratios between pre- and post-treatments. There was also a significant increase in serum NO levels in the pre-treatment values when compared to control (P < 0.001) and post-treatment measurements (P < 0.01). Our results strongly suggest that thiol/disulphide homeostasis and nitrosative stress can contribute to the pathogenesis of COVID-19. This study was the first to show that antiviral drug therapy can prevent the depletion in serum thiol levels and decrease serum NO levels in COVID-19 patients.

Plasma thiol and disulphide levels and their relationship with left ventricular systolic functions: A propensity score matching analysis.

OBJECTIVE: Left ventricular (LV) systolic function measured through LV ejection fraction (LVEF) has prognostic implications in patients with cardiac and non-cardiac conditions. The balance of thiol and disulphide levels reflects oxidative status in the body. In this study, we aimed to investigate the relationship between plasma thiol and disulphide levels, and LVEF calculated by transthoracic echocardiography (TTE). METHODS: This retrospective study included 1,048 patients referred for TTE examination and biochemical analyses, including plasma thiol and disulphide levels. After the application of exclusion criteria, the remaining 611 patients were included in the statistical analysis. Patients were classified into two groups, namely normal LVEF (n-LVEF) (n=446) and low LVEF (l-LVEF) (n=165) according to a cut-off level of LVEF 50%. To reduce sample selection bias and adjust for the influence of differences in patient characteristics on LVEF and oxidative status, 1: 1 propensity score matching analysis was applied. RESULTS: Propensity score matching analysis yielded 125 patients in both groups with comparable demographics, medications, and blood parameters. Native thiol and total thiol levels were lower in l-LVEF patients than in n-LVEF patients (p<0.001 for both), whereas disulphide levels were higher in l-LVEF group (p=0.008). Native thiol (r=0.384, p<0.001), total thiol (r=0.35, p<0.001), and disulphide levels (r=-0.129, p=0.004) significantly correlated with LVEF. CONCLUSION: Plasma thiol levels decrease and disulphide levels increase suggesting the presence of oxidative stress in patients with l-LVEF. Significant correlation between oxidative stress and LVEF sheds light about the possible pathogenetic role of thiol and disulphide in heart failure.

Thiol-disulfide homeostasis and ischemia-modified albumin as a marker of oxidative stress in patients with sarcopenia.

AIM: Sarcopenia is characterized by progressive and generalized loss of skeletal muscle mass and strength. Chronic inflammatory conditions and increased oxidative stress are in the pathogenesis of sarcopenia. Our aim was to evaluate the relationship between sarcopenia and thiol-disulfide homeostasis and ischemia-modified albumin levels as an oxidative stress marker. METHODS: Patients aged ≥65 years were recruited in this study. Sarcopenia was diagnosed according to the European Working Group on Sarcopenia in Older People criterion. Total thiol, native thiol, disulfide and ischemia-modified albumin levels were measures according to clinical and laboratory features. Patients were divided into two groups according to their sarcopenia presence; thiol-disulfide homeostasis and ischemia-modified albumin levels were evaluated between these groups. RESULTS: Overall, 94 patients were analyzed. The mean age was 75.0 ± 6.71 years. A total of 39% of the patients were diagnosed as probable sarcopenia, 3.2% had sarcopenia, 6.4% had severe sarcopenia and 51.1% were diagnosed as normal. The levels of native thiol, total thiol, disulfide level and disulfide-native thiol, native thiol-total thiol and disulfide-total thiol ratios were similar in patients with sarcopenia when compared with the control group. In addition, there were no differences between albumin and ischemia-modified albumin levels. In univariate regression analysis, handgrip strength was found to be an independent predictor of native thiol and total thiol, and disulfide levels. CONCLUSION: This is the first study in the literature that evaluates the thiol-disulfide homeostasis and ischemia-modified albumin levels in sarcopenic older patients. Long-term studies are warranted to confirm the relationship between oxidative stress markers and sarcopenia. Geriatr Gerontol Int 2021; 21: 584-589.

Comparison of serum human Klotho levels and thiol/disulfide homeostasis in women with polycystic ovary syndrome and in healthy women.

OBJECTIVES: Women with polycystic ovary syndrome (PCOS) have an increased cardiometabolic risk. Similarly, it was previously shown that atherosclerotic and cardiovascular risk is increased in the general population with lower serum Klotho levels. The aim of this study was to investigate the lotho and thiol/disulfide levels in women with non-obese PCOS compared to healthy controls and also to investigate the relationship of serum Klotho and thiol/disulfide homeostasis with cardiometabolic risk factors. MATERIALS AND METHODS: In this prospective case control study, human serum alpha Klotho levels and thiol/disulfide homeostasis of women with PCOS aged between 19-33 were compared to their age and BMI matched non - PCOS healthy controls. In addition, the correlation of these molecules with other metabolic markers/measurements were also investigated. RESULTS: Metabolic parameters such as mean waist circumference, lipid accumulation product, visceral adiposity index, fasting insulin, homeostasis model assessment of insulin resistance and triglyceride values were higher in the PCOS group (p = 0.038, p = 0.008, p = 0.001, p = 0.001, p = 0.002 and p = 0.002, respectively) compared to controls. However, mean serum Klotho and native thiol levels (respectively p < 0.0001 and p = 0.038) were lower compared to controls. Correlation analysis revealed that serum Klotho levels were negatively correlated with BMI, waist circumference, disulphide/total thiol, disulphide/native thiol, HOMA-IR and LAP-index. CONCLUSIONS: Findings of decreased serum Klotho and native thiol values of the PCOS group compared to controls and the negative correlation of serum Klotho levels with metabolic markers supports the idea that decreased Klotho may be another mechanism by which cardiovascular risk is increased in women with PCOS.

Erythrocyte reduced/oxidized glutathione and serum thiol/disulfide homeostasis in patients with rheumatoid arthritis.

BACKGROUND: 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.

An investigation into the clinical efficacy of thiol/disulfide hemostasis and ischemia-modified albumin in cases of gallbladder perforation.

BACKGROUND: In the presence of advanced age and comorbidities, patients with gallstones may face gangrenous and perforated cholecystitis during their follow-up. In the literature, dynamic thiol/disulfide homeostasis has been shown to play an important role in detoxification, antioxidant protection, regulation of enzymatic reactions, and apoptosis and cellular signaling mechanisms. In this study, we aimed to evaluate the efficacy of IMA and thiol/disulfide homeostasis in the preoperative diagnosis of patients with cholelithiasis, acute/chronic cholecystitis, and perforated gallbladder. METHODS: Sixty-six patients that presented to the General Surgery Clinic of Ankara City Hospital for a cholecystectomy operation between February 2019 and May 2020 were included in this study. The patients were divided into three groups depending on the condition for which they were scheduled for surgery: cholelithiasis, cholecystitis, and perforated gallbladder. The demographic data, history of cholecystitis, chronic disease, white blood cell (WBC), amylase, lipase and liver function tests (AST and ALT) were recorded before the operation. Gallbladder appearance was evaluated using hepatobiliary ultrasonography. The duration of surgery, pericholecystic adhesions, hospital stay, body mass index (BMI), postoperative complications, and pathology results of specimens were recorded. In addition, thiol/disulfide and IMA values were analyzed in the blood samples taken from the patients preoperatively. RESULTS: The mean native thiol and total thiol values of the patients with an adhesion score of 0 were significantly higher than those with an adhesion score value of 1, 2 or 3. In addition, the disulfide, disulfide/native thiol, native thiol/total thiol and IMA values of the cases with an adhesion score of 2 or 3 were significantly higher than those with an adhesion score of 0. The native thiol and total thiol averages of the patients with normal cholecystectomy were higher than the others. The disulfide, native thiol/total thiol and IMA averages of those who underwent cholecystectomy due to a perforated gallbladder were also higher than the other groups. The mean preoperative WBC of the patients who underwent cholecystectomy due to a perforated gallbladder was also significantly higher than the other groups. Lastly, the native thiol and total thiol values had a statistically significant negative correlation with age, operation time, and hospital stay, and a statistically significant positive relationship with BMI. CONCLUSION: We consider that in the preoperative diagnosis of the perforated gallbladder, the evaluation of thiol/disulfide hemostasis and IMA parameters can be used as an effective and reliable method to predict intraoperative difficulties.

Relationship between thiol, disulphide volume and contrast-induced nephropathy in acute coronary syndrome patients treated with percutaneous coronary intervention.

BACKGROUND: This study aimed to evaluate thiol disulphide volume for the risk of contrast-induced nephropathy (CIN) in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). METHODS: A total of 638 patients with ACS were enrolled in the study. CIN was defined as an increase in serum creatinine level of ≥0.5 mg/dL or ≥25% above baseline within 72 h after the procedure. Patients were divided into two groups: patients with and without CIN. Demographics, clinical risk factors, angiographic and laboratory parameters, CIN incidence, thiol, disulphide, and CHA2DS2-VASc score were compared between the two groups. RESULTS: Native thiol, total thiol, and disulphide at baseline were significantly lower in patients who developed CIN compared to those who did not. Also, the CHA2DS2-VASc score was found to be higher in patients with CIN than those without CIN. In receiver operating characteristic analysis showed that at a cutoff of <342.1, the value of native thiol exhibited 82% sensitivity and 80% specificity for detecting CIN. Total thiol< 383.1 calculated on admission had an 80% sensitivity and 80% specificity in predicting CIN. CONCLUSION: Our study suggested that the thiol disulphide volume on admission was independently associated with the development of CIN after PCI in patients with ACS.

Impaired Thiol/Disulfide Homeostasis in Children Diagnosed with Autism: A Case-Control Study.

Although genetic factors occupy an important place in the development of autism spectrum disorder (ASD), oxidative stress and exposure to environmental toxicants have also been linked to the condition. The aim of this study was to examine dynamic thiol/disulfide homeostasis in children diagnosed with ASD. Forty-eight children aged 3-12 years diagnosed with ASD and 40 age- and sex-matched healthy children were included in the study. A sociodemographic data form was completed for all the cases, and the Childhood Autism Rating Scale (CARS) was applied to the patients. Thiol/disulfide parameters in serum were measured in all cases and compared between the two groups. Mean native thiol, total thiol concentrations (µmol/L), and median reduced thiol ratios were significantly lower in the ASD group than in the control group (p = 0.001 for all). Median disulfide concentrations (µmol/L), redox potential, and median oxidized thiol ratios were significantly higher in the ASD group than in the control group (p = 0.001, p = 0.001, and p = 0.001, respectively). ROC analysis revealed that area under the curve (AUC) values with "excellent discriminatory potential," for native thiol, total thiol, the reduced thiol ration, the oxidized thiol ratio, and redox potential and with "acceptable discriminatory potential" for disulfide were significantly capable of differentiating individuals with ASD from healthy individuals. No correlation was determined between the severity of autism and laboratory parameters. Impaired dynamic thiol/disulfide homeostasis was observed in children with ASD, suggesting that dynamic thiol/disulfide homeostasis in serum may be of diagnostic value in autism.

Analysis of the Soil Fumigant, Dimethyl Disulfide, in Swine Blood by Dynamic Headspace Gas Chromatography-Mass Spectroscopy.

Plant parasites and soilborne pathogens directly reduce the overall yield of crops, vegetables, and fruits, negatively impacting the market demand for these products and their net profitability. While preplant soil fumigation helps maintain the consistent production quality of high-value cash crops, most soil fumigants are toxic to off-target species, including humans. Dimethyl disulfide (DMDS) has recently been introduced as a relatively low toxicity soil fumigant. Although DMDS exhibits low toxicity compared to other soil fumigants, it is volatile and exposure can cause eye, nasal, and upper respiratory tract irritation, skin irritation, nausea, dizziness, headache, and fatigue. While there is one analysis method available for DMDS from biological matrices, it has significant disadvantages. Hence, in this study, a dynamic headspace gas chromatography-mass spectroscopy (DHS-GC-MS) method was developed for the analysis of DMDS in swine whole blood. This method is highly sensitive and requires only three steps: 1) acid denaturation, 2) addition of internal standard, and 3) DHS-GC-MS analysis. The method produced a wide linear range from 0.1 - 200 µM with an excellent limit of detection of 30 nM. Intra- and interassay accuracy (100±14% and 100±11%, respectively) and precision (<5% and <6% relative standard deviation, respectively) were also excellent. The method worked well to quantify the DMDS levels in the blood of dimethyl trisulfide (DMTS)-treated swine (i.e., DMDS is a byproduct of DMTS treatment) with no interfering substances at or around the retention time of DMDS (i.e., 2.7 min). This simple, rapid, and extremely sensitive method can be used for the quantification of DMDS levels in blood to verify exposure to DMDS or to monitor levels of DMDS following DMTS treatment (e.g., for cyanide poisoning).

Thiol/disulfide homeostasis in retinitis pigmentosa patients.

PURPOSE: This research is aimed at determination of total oxidant status, total antioxidant status, serum thiol-disulfide, catalase, albumin, ischemia-modified albumin, and ceruloplasmin in patients suffering from retinitis pigmentosa and drawing a comparison with these parameters determined from healthy controls. METHODS: The study involved 35 patients of retinitis pigmentosa and 33 controls who were healthy individuals of comparable gender and age. Native thiol, total thiol, disulfide concentration, disulfide/native thiol, disulfide/total thiol, native thiol/total thiol ratios, total oxidant status, total antioxidant status, catalase, ceruloplasmin, albumin, and ischemia-modified albumin were determined from peripheral blood samples and comparison was drawn between the measurements of retinitis pigmentosa and controls. RESULTS: The two groups were similar in gender and age distributions. It was found that retinitis pigmentosa group demonstrated greater total oxidant status, ischemia-modified albumin, and disulfide concentrations as compared to controls (p < 0.001). However, total antioxidant status, catalase, native thiol, total thiol, albumin, and ceruloplasmin of the two groups did not show statistically significant difference (p > 0.05). Moreover, disulfide/total thiol and disulfide/native thiol ratios of the retinitis pigmentosa group were significantly greater in comparison to controls (p < 0.05). CONCLUSION: The researchers reached the conclusion that thiol oxidation in retinitis pigmentosa patients caused the dynamic thiol/disulfide homeostasis to shift toward the generation of disulfide. This is a novel research that involves analysis of thiol/disulfide homeostasis in retinitis pigmentosa patients using a novel automated assay. The researchers identified the cause for persistent oxidative stress and damage reported in retinitis pigmentosa patients. Still, future research is required for analysis of progression of antioxidant-oxidant state through various retinitis pigmentosa stages.

Dynamic thiol/disulphide homeostasis metrics as a risk factor for peripheral arterial disease.

OBJECTIVE: To examine dynamic thiol/disulphide homeostasis metrics as a novel risk factor of oxidative stress in patients with peripheral arterial disease. METHODS: One hundred patients with lower extremity peripheral arterial disease (a study group) and 100 control subjects were included in this prospective case-control study. Participants' baseline clinical characteristics and laboratory data including some oxidant/antioxidant status parameters such as albumin, ferroxidase and myeloperoxidase, and thiol/disulphide homeostasis parameters such as native thiol, total thiol and disulphide, as well as native thiol/total thiol, disulphide/native thiol and disulphide/total thiol ratios were all recorded and then compared between the groups. RESULTS: Mean albumin and ferroxidase, and median myeloperoxidase levels were found to be significantly higher in patients with the peripheral arterial disease than in control group (p = 0.045, p = 0.000 and p = 0.000, respectively). Mean native thiol and total thiol, and median disulphide levels were found to be significantly lower in the study group as compared with the control group (p = 0.000, p = 0.000 and p = 0.037, respectively). According to the results of logistic regression analysis, systolic blood pressure, ferroxidase and myeloperoxidase levels were detected to be the independent predictors of peripheral arterial disease. CONCLUSION: Our report is the first one in the literature investigating dynamic thiol/disulphide homeostasis metrics as a novel risk factor of oxidative stress in peripheral arterial disease. Dynamic thiol/disulphide homeostasis metrics may be used as a valuable risk factor of oxidative stress in patients with the peripheral arterial disease since it is readily available, easily calculated and relatively cheap.

Ischemia-Modified Albumin Levels and Thiol-Disulphide Homeostasis in Diabetic Macular Edema in Patients with Diabetes Mellitus Type 2.

PURPOSE: It was aimed to assess the role of thiol-disulphide homeostasis and ischemia-modified albumin (IMA) level in the development of diabetic macular edema (DME) in patients with diabetes mellitus type 2 (T2DM). MATERIALS AND METHODS: Sixty-six study patients were divided into two groups. Group I included 43 patients with T2DM and DME, and Group 2 included 23 patients with T2DM without eye involvement. A novel colorimetric method was used to assess thiol-disulphide homeostasis. Between the two groups IMA, total anti-oxidant, and total oxidant levels were measured and compared. RESULTS: In Group 1, total and native thiol levels and disulphide levels were lower compared to Group 2 (p = .025, p < .001 and p = .013, respectively). Disulphide/native thiol, disulphide/total thiol ratios and native thiol/total thiol were similar between the groups. Total anti-oxidant level (TAL) reduced whereas total oxidant level (TOL) increased in Group 1 compared to Group 2 (p = .001, p = .002, respectively). Albumin level decreased, whereas IMA level increased in Group 1 compared to Group 2 (p < .001 for both). CONCLUSIONS: The disruption in thiol/disulphide homeostasis, increased IMA and oxidative stress have an impact on the development of diabetic macular edema.

Efficacy of Thiol Disulfide Homeostasis and Ischemia Modified Albumin Values in Estimating the Degree of Difficulty for Laparoscopic Cholecystectomy.

AIM: The aim of this study was to investigate the efficacy of thiol disulfide homeostasis and Ischemia Modified Albumin (IMA) values in predicting the technical difficulties that might be encountered during laparoscopic cholecystectomy. MATERIALS AND METHODS: The study included 65 patients who underwent laparoscopic cholecystectomy due to cholelithiasis at the General Surgery Clinic of Ankara Numune Training and Research Hospital. All patients' demographic data, previous history of cholecystitis, a history of chronic illness, preoperative white blood count (WBC), liver function tests (AST, ALT), amylase and lipase levels, intra-operative adhesion score, the ultrasonographic appearance of gall bladder, duration of hospital stay, duration of operation, thiol disulfide and IMA values were evaluated. RESULTS: Native thiol and total thiol averages were higher in patients without a history of cholecystitis, and on the other hand, disulfide, disulfide/native thiol rate, disulfide/total thiol rate, native thiol/total thiol rate and IMA averages were higher in patients with a history of cholecystitis. While there was a statistically significant negative correlation between native and total thiol values and age, duration of surgery and duration of hospital stay; IMA, disulfide, disulfide/Total thiol, Native/Total thiol and disulfide/Native thiol rates were higher in older patients with a longer duration of surgery and hospital stay. In addition, preoperative IMA, disulfide, disulfide/Total thiol, Native/Total thiol and disulfide/Native thiol were observed to increase as the degree of intraoperative pericholecystic adhesion increased. CONCLUSION: We believe that the evaluation of thiol disulfide homeostasis and IMA parameters prior to laparoscopic cholecystectomy can be used as an effective method for predicting intraoperative difficulties.

Increased oxidative stress is associated with thiol/disulphide homeostasis in clomiphene citrate resistant polycystic ovary syndrome.

The purpose of this study was to evaluate the relation CC resistant PCOS and the thiol/disulphide homeostasis, used as a marker of OS, by measuring that exchange using a novel technique. Sixty women patients admitted to the infertility clinic were evaluated. The patients were divided into two groups. Group 1 comprised 30 infertile PCOS patients with CC resistance; Group 2 was the control group comprising 30 infertile PCOS patients with CC sensitivity. Serum total thiol (p = .024), native thiol (p = .0052), disulphide (p = .003), index 1 (p = .001), index 2 (p = .001) and index 3 (p = .001), HOMA-IR (p < .001) and free testosterone (p < .001) were statistically significant. The independent variables BMI and age effects were adjusted according to the logistic regression method with groups. Significant differences were observed between the two groups in the levels of native thiol (p* = .0042), total thiol (p* = .024), disulphide (p* = .0003), index 1 (p* = .0001) index 2 (p*= .0001), index 3 (p* = .0001), HOMA-IR (p* = .0044), insulin (p*= .032) and free testosterone (p* = .0001) values. The thiol/disulphide homeostasis viewed in favour of OS. Like a reflection of OS in the follicular endocrine microenvironment may be linked with increased thiol/disulphide homeostasis, free testosterone, insulin and HOMA-IR levels.Impact statementWhat is already known about this subject? In previous studies, thiol/disulphide homeostasis was compared between PCOS and control groups. In this study, serum thiol/disulphide homeostasis was measured in infertile PCOS patients resistant to CC for the first time.What do the results of this study add? Disulphide concentrations were significantly higher in patients with CC resistant patients thanthe control group. This shows us that more OS occurs in the CC-resistant group.What are the implications of these findings for clinical practice and further research? Thiol/disulphide homeostasis will be a guide for PCOS management in patients with CC-resistant PCOS.