Comparative analysis of thiol-disulfide homeostasis dynamics between elective cesarean section and uncomplicated vaginal delivery: insights into perinatal oxidative balance.

OBJECTIVE: 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.

The role of oxidative stress in chemotherapy-induced gonadotoxicity in a rat model, and the protective effects of Nigella Sativa oil on oxidative stress, the anti-Müllerian hormone level, and apoptosis.

OBJECTIVE: This study aimed to determine the role of oxidative stress (OS) in carboplatin-induced gonadotoxicity and whether Nigella Sativa oil (NSO), an herbal antioxidant, has a protective effect on ovarian apoptosis, OS, and the anti-Müllerian hormone (AMH) level in a rat model. MATERIALS AND METHODS: The study included 24 adult female rats that were divided into 4 treatment groups. Group A saline + saline (sham group); group B: NSO + saline; group C: saline + carboplatin; group D: NSO + carboplatin. Saline, NSO, and carboplatin were administered intraperitoneally 24 and/or 48 h before sacrification as 4 mL/kg, 4 mL/kg, and 80 mg/kg, respectively. Apoptosis, OS parameters, and AMH were measured. RESULTS: Oxidant levels and apoptosis were higher, whereas AMH and the antioxidants were lower in group C than in group A. Apoptosis, OS parameters, and AMH levels were negatively affected by chemotherapy (CTx) in group C whilst improvement in those parameters was observed in group D following NSO pretreatment. The levels of apoptosis and malondialdehyde (MDA), an OS parameter, in group D were lower than in group C as they declined from 34.3% to 8.65% (p = 0.002) and from 199.4 nmol/g tissue to 136.4 nmol/g tissue (p = 0.002), respectively. However, the slight increase in AMH level from 2.7 ng/mL to 3.5 ng/mL due to the NSO effect was not significant between groups C and D. CONCLUSIONS: The present findings show that carboplatin has adverse effects on AMH, ovarian tissue apoptosis, and OS parameters. NSO pretreatment might protect ovarian tissue and decrease CTx-induced ovarian injury by decreasing OS and apoptosis, but the protective effect of NSO on AMH is limited.

Diagnostic utility of oxidative and non-oxidative markers for spontaneous bacterial peritonitis in non-malign ascites.

OBJECTIVE: In this study, we aimed to investigate the diagnostic availability of oxidant and antioxidant parameters in ascites for spontaneous bacterial peritonitis (SBP). MATERIAL AND METHODS: This study was carried out between July and October 2018 with 25 patients with SBP and 24 patients without SBP. Patients with acute infection, those taking vitamin supplements and antioxidant medication, smoking and drinking alcohol, and patients without ascites culture were excluded from the study. RESULTS: In patients with SBP compared those without SBP median paraoxonase (3.1 vs 15.6 ; p <0.001), median stimulated paraoxonase (12.6 vs 53.1 ; p <0.001), median arylesterase (769,9 vs 857,5 ; p = 0,003) and median catalase (10 vs 22,2 ; p = 0,003) were found to be lower and median myeloperoxidase (8.1 vs 1.1 ; p <0.001) were found to be higher. There was a positive correlation between paraoxonase levels and stimulated paraoxonase levels, arylesterase levels and catalase levels, there was a negative correlation between paraoxonase levels and myeloperoxidase levels. Paraoxonase levels 3.7 and lower, stimulated paraoxonase levels 25.8 and lower, arylesterase levels 853.4 and lower, catalase levels 11.8 and lower and myeloperoxidase levels 2.7 and more predicted the the presence of SBP with high specificity and high sensitivity. Paraoxonase and stimulated paraoxo-nase levels were found to have superior performance in predicting the presence of SBP compared to arylesterase levels (p <0.05). CONCLUSION: In this study it was shown that paraoxonase, stimulated paraoxonase, arylesterase, catalase and myeloperoxidase activities can be used for the diagnosis and severity of SBP.

The relationship between severity of ulcerative colitis and thiol-disulphide homeostasis.

OBJECTIVES: The aim of the study was to determine dynamic thiol-disulphide homeostasis in patients with ulcerative colitis, compare it with those of healthy control and to investigate the relationship between the severity of the disease and homeostasisMETHODS: A total of 78 patients and 58 healthy subjects were included in the study. Serum native thiol, total thiol and disulphide amounts were measured by using a novel automated method. Obtained results were compared and relationships were determined by correlation analysis. RESULTS: Serum native thiol, total thiol, disulphide amounts and disulphide/native thiol percent ratio (index) were significantly lower (p = 0.003 for index ratio and p < 0.001 for other parameters) in patients with ulcerative colitis than in healthy controls. Native thiol, total thiol and disulphide amounts were significantly higher (p < 0.001) in patients with ulcerative colitis in remission than in patients with active ulcerative colitis and near to those of healthy control. There were significant negative correlations between the severity of the disease and thiol-disulphide homeostasis parameters (r = -0.55, p < 0.001 for native thiol; r = -0.64, p < 0.0001 for total thiol; r = -0.65, p < 0.001 for disulphide and r = -0.33, p = 0.011 for index). CONCLUSION: The thiol-disulphide homeostasis was weakened in ulcerative colitis. Strong correlations between the activity of the disease and thiol-disulfide homeostasis indicate that homeostasis may play a role in the pathogenesis of the disease (Tab. 3, Fig. 3, Ref. 30).

Thiol/disulphide homeostasis levels in erectile dysfunction patients.

This study explored the use of thiol/disulphide homeostasis as a novel oxidative stress marker in patients with erectile dysfunction (ED). Fifty-five patients aged 40-57 were divided into two groups: Group I (International Index of Erectile Function [IIEF-5] score between 22 and 25, n = 20) and Group II (IIEF-5 score < 22, n = 35). Blood samples were used to evaluate hormone levels, lipid profile and thiol/disulphide levels. A novel, fully automated method measured plasma native thiol, total thiol and disulphide levels. Mean age, body mass index, total testosterone, HbA1c, triglyceride, atherogenic index (AIP) and total cholesterol levels did not significantly differ between Groups I and II (p > .05). IIEF-5 correlated weakly with native thiol level. Although non-statistically significant, native thiol (431 [SD: 105] µmol/L vs. 404 [110] µmol/L) and total thiol (426 [64] µmol/L vs. 41 [78] µmol/L) levels were lower in the ED group compared to the controls, and disulphide (14 [11] µmol/L vs. 18 [9] µmol/L) levels were higher. Mean disulphide/native thiol and mean disulphide/total thiol ratios did not statistically differ between groups. There was a weak positive correlation between AIP and total cholesterol/HDL and disulphide and disulphide/total thiol ratios. Thiol/disulphide haemostasis levels are not a single factor in ED pathophysiology but may contribute.

Thiol/disulfide homeostasis in postmenopausal osteoporosis.

AIM: To evaluate the impact of postmenopausal osteoporosis on thiol/disulfide homeostasis. MATERIALS AND METHODS: A total of 75 participants were divided into two groups: Group 1 (n = 40) was composed of healthy postmenopausal women, and group 2 (n = 35) was composed of women with postmenopausal osteoporosis. Clinical findings and thiol/disulfide homeostasis were compared between the two groups. RESULTS: The disulfide/native thiol ratio was 8.6% ± 3.6 in group 1 and 12.7% ± 8.4 in group 2 (p = 0.04). The disulfide/native thiol percent ratio was significantly higher in group 2 after adjustment for the years since menopause and age (p < 0.05). The native thiol/total thiol percent ratio was 85.6% ± 4.8 in group 1 and 73.8% ± 24.9 in group 2 (p = 0.01). The native thiol/total thiol percent ratio was significantly lower in group 2 after adjustment for the years since menopause and age (p < 0.05). CONCLUSION: Thiol/disulfide homeostasis shifted to the disulfide side independent of age and years since menopause in postmenopausal osteoporosis.

Comparison of thiol/disulphide homeostasis parameters in patients with COPD, asthma and ACOS.

OBJECTIVE: Chronic obstructive pulmonary disease (COPD), asthma and asthma-COPD overlap syndrome (ACOS) are obstructive pulmonary disorders with different manifestations. Status of oxidation in tissues is important in obstructive pulmonary disorders. Smoking, acute exacerbations of COPD and asthma were associated with a marked imbalance in oxidant or antioxidant status due to increased oxidative stress in tissues and blood. Oxidative conditions may cause a reversible formation of mixed disulphides among protein thiol groups. The aim of this study was to compare parameters related with thiol/disulphide homeostasis in patients with COPD, asthma and ACOS. PATIENTS AND METHODS: Patients (n= 135, 69 females, 66 males) who were referred with a diagnosis of COPD, asthma or ACOS were included in the study. Thiol/ disulphide homeostasis parameters in blood were analysed by a newly established method that measures the exact thiol/ disulphide status in the body. RESULTS: The patients with COPD, asthma or ACOS were similar for demographic parameters other than age and number of cigarettes smoked. Measured thiol/disulphide homeostasis parameters were similar among these patient groups. When these biochemical measurements were adjusted for age and number of cigarettes by using regression analysis, similarity for thiol/disulphide homeostasis parameters among patient groups persisted. CONCLUSIONS: To best of our knowledge, this is the first study to compare thiol/disulphide homeostasis parameters in COPD, asthma and ACOS patients. Similarity of thiol/disulphide homeostasis parameters among these patient groups supports the current view of Dutch hypothesis that COPD, asthma and ACOS share similar pathophysiological features but display different clinical manifestations.