Measuring the poise of thiol/disulfide couples in vivo

Impact of homocysteine on acute ischemic stroke severity: possible role of aminothiols redox status

BACKGROUND

Acute ischemic stroke (AIS) is one of the most common cerebrovascular diseases which accompanied by a disruption of aminothiols homeostasis. To explore the relationship of aminothiols with neurologic impairment severity, we investigated four aminothiols, homocysteine (Hcy), cysteine (Cys), cysteinylglycine (CG) and glutathione (GSH) in plasma and its influence on ischemic stroke severity in AIS patients.

METHODS

A total of 150 clinical samples from AIS patients were selected for our study. The concentrations of free reduced Hcy (Hcy), own oxidized Hcy (HHcy), free reduced Cys (Cys), own oxidized Cys (cysteine, Cyss), free reduced CG (CG) and free reduced GSH (GSH) were measured by our previously developed hollow fiber centrifugal ultrafiltration (HFCF-UF) method coupled with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The concentration ratio of Hcy to HHcy (Hcy/HHcy), Cys to Cyss (Cys/Cyss) were also calculated. The neurologic impairment severity of AIS was evaluated using National Institutes of Health Stroke Scale (NIHSS). The Spearman correlation coefficient and logistic regression analysis was used to estimate and perform the correlation between Hcy, HHcy, Cys, Cyss, CG, GSH, Hcy/HHcy, Cys/Cyss and total Hcy with NIHSS score.

RESULTS

The reduced Hcy and Hcy/HHcy was both negatively correlated with NIHSS score in AIS patients with P = 0.008, r=-0.215 and P = 0.002, r=-0.249, respectively. There was no significant correlation of Cys, CG, GSH, HHcy, Cyss, Cys/Cyss and total Hcy with NIHSS score in AIS patients with P value > 0.05.

CONCLUSIONS

The reduced Hcy and Hcy/HHcy, not total Hcy concentration should be used to evaluate neurologic impairment severity of AIS patient.

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.

Valproic Acid Causes Redox-Regulated Post-Translational Protein Modifications That Are Dependent upon P19 Cellular Differentiation States

Valproic acid (VPA) is a common anti-epileptic drug and known neurodevelopmental toxicant. Although the exact mechanism of VPA toxicity remains unknown, recent findings show that VPA disrupts redox signaling in undifferentiated cells but has little effect on fully differentiated neurons. Redox imbalances often alter oxidative post-translational protein modifications and could affect embryogenesis if developmentally critical proteins are targeted. We hypothesize that VPA causes redox-sensitive post-translational protein modifications that are dependent upon cellular differentiation states. Undifferentiated P19 cells and P19-derived neurons were treated with VPA alone or pretreated with D3T, an inducer of the nuclear factor erythroid 2-related factor 2 (NRF2) antioxidant pathway, prior to VPA exposure. Undifferentiated cells treated with VPA alone exhibited an oxidized glutathione redox couple and increased overall protein oxidation, whereas differentiated neurons were protected from protein oxidation via increased S-glutathionylation. Pretreatment with D3T prevented the effects of VPA exposure in undifferentiated cells. Taken together, our findings support redox-sensitive post-translational protein alterations in undifferentiated cells as a mechanism of VPA-induced developmental toxicity and propose NRF2 activation as a means to preserve proper neurogenesis.

Obesogenic polystyrene microplastic exposures disrupt the gut-liver-adipose axis

Microplastics (MP) derived from the weathering of polymers, or synthesized in this size range, have become widespread environmental contaminants and have found their way into water supplies and the food chain. Despite this awareness, little is known about the health consequences of MP ingestion. We have previously shown that the consumption of polystyrene (PS) beads was associated with intestinal dysbiosis and diabetes and obesity in mice. To further evaluate the systemic metabolic effects of PS on the gut-liver-adipose tissue axis, we supplied C57BL/6J mice with normal water or that containing 2 sizes of PS beads (0.5 and 5 µm) at a concentration of 1 µg/ml. After 13 weeks, we evaluated indices of metabolism and liver function. As observed previously, mice drinking the PS-containing water had a potentiated weight gain and adipose expansion. Here we found that this was associated with an increased abundance of adipose F4/80+ macrophages. These exposures did not cause nonalcoholic fatty liver disease but were associated with decreased liver:body weight ratios and an enrichment in hepatic farnesoid X receptor and liver X receptor signaling. PS also increased hepatic cholesterol and altered both hepatic and cecal bile acids. Mice consuming PS beads and treated with the berry anthocyanin, delphinidin, demonstrated an attenuated weight gain compared with those mice receiving a control intervention and also exhibited a downregulation of cyclic adenosine monophosphate (cAMP) and peroxisome proliferator-activated receptor (PPAR) signaling pathways. This study highlights the obesogenic role of PS in perturbing the gut-liver-adipose axis and altering nuclear receptor signaling and intermediary metabolism. Dietary interventions may limit the adverse metabolic effects of PS consumption.

Erythrocyte metabolism

Our aim is to present an updated overview of the erythrocyte metabolism highlighting its richness and complexity. We have manually collected and connected the available biochemical pathways and integrated them into a functional metabolic map. The focus of this map is on the main biochemical pathways consisting of glycolysis, the pentose phosphate pathway, redox metabolism, oxygen metabolism, purine/nucleoside metabolism, and membrane transport. Other recently emerging pathways are also curated, like the methionine salvage pathway, the glyoxalase system, carnitine metabolism, and the lands cycle, as well as remnants of the carboxylic acid metabolism. An additional goal of this review is to present the dynamics of erythrocyte metabolism, providing key numbers used to perform basic quantitative analyses. By synthesizing experimental and computational data, we conclude that glycolysis, pentose phosphate pathway, and redox metabolism are the foundations of erythrocyte metabolism. Additionally, the erythrocyte can sense oxygen levels and oxidative stress adjusting its mechanics, metabolism, and function. In conclusion, fine-tuning of erythrocyte metabolism controls one of the most important biological processes, that is, oxygen loading, transport, and delivery.

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.

Association of occupational exposure to pesticides with overweight in farmers in Southern Brazil

INTRODUCTION

Exposure to pesticides may be related to overweight and associated comorbidities. The aim of this work was to evaluate occupational exposure to pesticides, overweight and associated comorbidities among farmers in Southern Brazil.

METHODS

This cross-sectional study included a random sample of 257 farmers, living in the municipality of Mafra and Planalto, southern Brazil. Data on pesticide use and overweight prevalence from farmers were collected using an in-person interview questionnaire, followed by blood collection and biochemical analyses.

RESULTS

Pesticide exposure was positively correlated with body mass index, waist circumference, waist-to-hip ratio, triglycerides and glucose levels, presence of hypertension and metabolic syndrome. Besides that, the fact of being exposed to pesticides represents a decrease of no protein thiol groups. Furthermore, the main pesticides used by farmers have hepatic toxicity.

CONCLUSION

These findings suggest that exposure to pesticides may be associated with overweight and associated comorbidities. Further studies are required to validate our findings and elucidate the specific mechanisms by which these pollutants contribute to the development of overweight.

The Key Role of GSH in Keeping the Redox Balance in Mammalian Cells: Mechanisms and Significance of GSH in Detoxification via Formation of Conjugates

Glutathione (GSH) is a ubiquitous tripeptide that is biosynthesized in situ at high concentrations (1-5 mM) and involved in the regulation of cellular homeostasis via multiple mechanisms. The main known action of GSH is its antioxidant capacity, which aids in maintaining the redox cycle of cells. To this end, GSH peroxidases contribute to the scavenging of various forms of ROS and RNS. A generally underestimated mechanism of action of GSH is its direct nucleophilic interaction with electrophilic compounds yielding thioether GSH S-conjugates. Many compounds, including xenobiotics (such as NAPQI, simvastatin, cisplatin, and barbital) and intrinsic compounds (such as menadione, leukotrienes, prostaglandins, and dopamine), form covalent adducts with GSH leading mainly to their detoxification. In the present article, we wish to present the key role and significance of GSH in cellular redox biology. This includes an update on the formation of GSH-S conjugates or GSH adducts with emphasis given to the mechanism of reaction, the dependence on GST (GSH S-transferase), where this conjugation occurs in tissues, and its significance. The uncovering of the GSH adducts' formation enhances our knowledge of the human metabolome. GSH-hematin adducts were recently shown to have been formed spontaneously in multiples isomers at hemolysates, leading to structural destabilization of the endogenous toxin, hematin (free heme), which is derived from the released hemoglobin. Moreover, hemin (the form of oxidized heme) has been found to act through the Kelch-like ECH associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor-2 (Nrf2) signaling pathway as an epigenetic modulator of GSH metabolism. Last but not least, the implications of the genetic defects in GSH metabolism, recorded in hemolytic syndromes, cancer and other pathologies, are presented and discussed under the framework of conceptualizing that GSH S-conjugates could be regarded as signatures of the cellular metabolism in the diseased state.

Evaluation of Thiol/Disulfide Interrelation in Major Depressive Disorder

Objective

Although major depressive disorder (MDD) constitutes a significant part of mental health problems, its pathogenesis has not been fully elucidated. The inadequacy of diagnostic tests specific to MDD causes difficulty in diagnosis. Therefore, we investigated the situation of thiol/disulfide imbalance, which may play a role in the pathogenesis of many diseases, in MDD patients.

Methods

Forty-five MDD patients and 40 non-patient volunteers participated in our study. Sociodemographic data form, Beck Depression Scale, and Clinical Global Impression Scale were used in making the diagnosis and evaluation process.

Results

There was a significant difference between the MDD and non-patient groups in native thiol and total thiol levels, disulfide/native thiol, disulfide/total thiol, and native thiol/total thiol ratios. No significant difference was detected in terms of disulfide level between the 2 groups. There was no significant difference between the patients' thiol disulfide ratios and the severity of depression. There was no significant difference between the patients' symptom duration and thiol disulfide ratios. Nevertheless, a negative correlation was identified between the duration of the patients' symptoms and their disulfide levels.

Conclusion

When the results were examined in terms of thiol and disulfide ratios, they showed that thiol and disulfide ratios were impaired in depression. We think that thiol/disulfide parameters may be a biomarker candidate that can help in the diagnosis of MDD.

Sex-specific effects of acute chlordane exposure in the context of steatotic liver disease, energy metabolism and endocrine disruption

Chlordane is an organochlorine pesticide (OCP) that is environmentally persistent. Although exposures to OCPs including chlordane have been associated with elevated liver enzymes, current knowledge on OCPs' contribution to toxicant-associated steatotic liver disease (TASLD) and underlying sex-specific metabolic/endocrine disruption are still widely limited. Therefore, the objective of this study was to investigate the sex-dependent effects of chlordane in the context of TASLD. Age-matched male and female C57BL/6 mice were exposed to chlordane (20 mg/kg, one-time oral gavage) for two weeks. Female mice generally exhibited lower bodyfat content but more steatosis and hepatic lipid levels, consistent with increased hepatic mRNA levels of genes involved in lipid synthesis and uptake. Surprisingly, chlordane-exposed females demonstrated lower hepatic cholesterol levels. With regards to metabolic disruption, chlordane exposure decreased expression of genes involved in glycogen and glucose metabolism (Pklr, Gck), while chlordane-exposed females also exhibited decreased gene expression of HNF4A, an important regulator of liver identity and function. In terms of endocrine endpoints, chlordane augmented plasma testosterone levels in males. Furthermore, chlordane activated hepatic xenobiotic receptors, including the constitutive androstane receptor, in a sex-dependent manner. Overall, chlordane exposure led to altered hepatic energy metabolism, and potential chlordane-sex interactions regulated metabolic/endocrine disruption and receptor activation outcomes.

The kinetics of glutathione in the gastrointestinal tract of weaned piglets supplemented with different doses of dietary reduced glutathione

This study aimed to investigate the kinetics of dietary GSH in the gastrointestinal tract and the effect of GSH on the intestinal redox status of weaned piglets. Forty-eight piglets with an average age of 26 days and an average body weight of 7.7 kg were used in this study. The piglets were divided into three treatment groups including the control group with a basal diet (CON) and two GSH groups with a basal diet supplemented with 0.1% GSH (LGSH) and 1.0% GSH (HGSH), respectively. The basal diet did not contain any GSH. The experiment lasted for 14 days, with eight animals sampled from each group on d5 and 14. The parts of 0-5%, 5-75%, and 75-100% of the length of the small intestine were assigned to SI1, SI2, and SI3. The results showed that GSH almost completely disappeared from the digesta at SI2. However, no difference in the GSH level in mucosa, liver, and blood erythrocytes was found. The level of cysteine (CYS) in SI1 digesta was significantly higher in HGSH than CON and LGSH on d14, and similar findings were observed for cystine (CYSS) in SI3 digesta on d5. The CYSS level in HGSH was also significantly higher than LGSH in the stomach on d14, while no CYS or CYSS was detected in the stomach for control animals, indicating the breakdown of GSH to CYS already occurred in the stomach. Irrespective of the dietary treatment, the CYS level on d14 and the CYSS level on d5 and 14 were increased when moving more distally into the gastrointestinal tract. Furthermore, the mucosal CYS level was significantly increased at SI1 in the LGSH and HGSH group compared with CON on d5. Glutathione disulfide (GSSG) was recovered in the diets and digesta from the LGSH and HGSH group, which could demonstrate the auto-oxidation of GSH. It is, therefore, concluded that GSH supplementation could not increase the small intestinal mucosal GSH level of weaned piglets, and this could potentially relate to the kinetics of GSH in the digestive tract, where GSH seemed to be prone to the breakdown to CYS and CYSS and the auto-oxidation to GSSG.

Are Thiol/Disulfide and 8-OHdG Levels in the Blood of Patients with Diabetic Foot a Risk Factor for Amputation?

OBJECTIVE

As diabetic patients live longer and there are more effective treatments available, the incidence of diabetes and its complications is increasing. The effects of oxidative stress and antioxidant processes on diabetes behavior, especially diabetic foot, are really direct. The goal of this research is to investigate the effects of oxidative stress and antioxidant mechanism on the outcome of amputation by examining the levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and thiol/disulfide in the blood of patients diagnosed with diabetic foot.

METHODS

The research consisted of 76 patients with type 2 diabetes with associated diabetic foot, ages 40-65 (51 men, 25 women). Patients with diabetic foot wounds and accompanying peripheral artery disease were not included in the study. After a mean follow-up of 9.6 months, 28 patients resulted in amputation. Between patients who required amputation and those who did not, the levels of 8-OHdG, native thiol, total thiol, disulfide, native thiol/total thiol ratio, disulfide/native thiol ratio, and disulfide/total thiol ratio were compared. Additionally, the age, sex, Wagner stage, and amputation outcome of these 2 patient groups were compared.

RESULTS

The outcomes of amputation in diabetic foot patients were not related to the levels of native thiol, total thiol, disulfide, native thiol/total thiol ratio, disulfide/native thiol ratio, total thiol/disulfide ratio, or 8-OHdG (P > .05). However, patients with diabetic foot who were male, older, and at a more advanced Wagner stage had a higher rate of amputations (P < .05).

CONCLUSION

Oxidative stress and antioxidant mechanism are effective on diabetes complications. However, since there are many factors affecting the outcome of amputation, they are not directly effective in terms of resulting amputation in patients with diabetic foot ulcer.

Changes in Dynamic Thiol/Disulfide Homeostasis, and Substance P, B-Endorphin and α-Tocopherol Concentrations in the Spinal Cord of Chronically Lame Dairy Cows

Initial lameness inflammation leads to chronic lameness and development of chronic pain due to the release of pro-inflammatory mediators such as reactive oxygen species (ROS), which are implicated in the transition from acute to chronic pain, and free radical scavengers countering thiol, substance P (SP), and β-endorphin (BE). The present study aimed to evaluate the dynamic thiol-disulfide homeostasis, α-tocopherol concentrations and SP and BE concentrations in the spinal cord of chronically lame dairy cows. Ten lame and 10 non-lame cows with a parity range of 2-6 were selected for the study. Lame cows had a history of up to 3 months of lameness. Spinal cord samples were obtained from the L2 to L4 lumbar vertebrae aspect of each animal. A thiol-disulfide homeostasis assay was performed using absorbance, and the α-tocopherol concentration was determined by HPLC. SP and BE concentrations were measured using ELISA kits. The results indicated that SP and BE were significantly higher in the spinal cord of lame cows. In contrast, disulfide levels and α-tocopherol concentrations were significantly lower in the spinal cord of lame cows. In conclusion, disulfide levels and α-tocopherol concentrations indicated a defective antioxidant response in cows with chronic lameness. The results of SP and BE concentrations suggested chronic pain and a defective endogenous analgesic response.

A more accurate indicator to evaluate oxidative stress in rat plasma with osteoporosis

Background: oxidative stress is linked to various human diseases which developed into the idea of "disrupted redox signaling". Osteoporosis (OP) is a chronic skeletal disorder characterized by low bone mineral density and deterioration of bone microarchitecture among which estrogen deficiency is the main cause. Lack of estrogen leads to the imbalance between oxidation and anti-oxidation in patients, and oxidative stress is an important link in the pathogenesis of OP. The ratio of the reduced to the oxidized thiols can characterize the redox status. However, few methods have been reported for the simultaneous determination of reduced forms and their oxidized forms of thiols in plasma. Methods: we developed a hollow fiber centrifugal ultrafiltration (HFCF-UF) method for sample preparation and validated a high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method to determine two reduced forms of thiols-homocysteine (Hcy), cysteine (Cys) levels and their respective oxidized compounds, homocystine (HHcy) and cystine (Cyss) in rat plasma simultaneously for the first time. Thirty-six female rats were randomly divided into three groups: normal control (NC), oxidative stress (ovariectomy, OVX) and ovariectomy with hydrogen-rich saline administration (OVX + HRS). Results: the validation parameters for the methodological results were within the acceptance criteria. There were both significant differences of Hcy/HHcy (Hcy reduced/oxidized) and Cys/Cyss (Cys reduced/oxidized) in rat plasma between three groups with both p < 0.05 and meanwhile, the p values of malondialdehyde, superoxide dismutase and glutathione peroxidase were all less than 0.01. The value of both Hcy/HHcy and Cys/Cyss were significantly decreased with the change of Micro-CT scan result of femoral neck in OVX group (both the trabecular thickness and trabecular number significantly decreased with a significant increase of trabecular separation) which demonstrate OP occurs. The change of Hcy/HHcy is more obvious and prominent than Cys/Cyss. Conclusions: the Hcy/HHcy and Cys/Cyss could be suitable biomarkers for oxidative stress and especially Hcy/HHcy is more sensitive. The developed method is simple and accurate. It can be easily applied in clinical research to further evaluate the oxidative stress indicator for disease risk factors.

An evaluation of trace elements and oxidative stress in patients with benign paroxysmal positional vertigo

OBJECTIVES

Vertigo and Dizziness are a common complaint among the reasons for applying to the ear nose throat clinic. Benign Paroxysmal Positional Vertigo (BPPV) is the most common cause of perpheric vertigo. Oxidative stress is caused by the formation of hydroxyl radicals, superoxide anions and hydrogen peroxide, which are reactive oxygen derivatives (ROS). The aim of this study is to investigate the relationship between complaints and serum trace element and oxidative stress levels in patients with BPPV.

METHODS

This study was conducted with 66 adult patients who presented to the ENT policlinic with the complaint of vertigo and were diagnosed with BPPV between May 2020 and September 2020. Blood samples were taken from patients diagnosed with BPPV to measure serum Zn and Cu levels and oxidative stress levels during an attack.

RESULTS

The mean ages of the study patients and healthy controls were 45.7 ± 15.1 and 44.7±13.2. Female / Male ratio were 28(42.5%)/38(57.5%) and 32(48.5%)/34(51.5%) in study and control group. We found serum Cu levels were lower in the patient group (p <0.05). Serum Total Thiol and Native Thiol values were lower in patients with BPPV. Total Thiol results were statistically significant.(p<0.05) Disulfide values were significantly higher in the disease group. (P <0.05). Thiol Oxidized / Thiol Reduced ratio (2243.6±6.7/343.8±125.3) was higher in control group. (p<0.05).

CONCLUSION

Serum oxidative stress and trace elements play a role in the pathophysiology of BPPV. We present the cut-off values for Cu and Zn in vertigo patients for the first time in the literature. We think that these cut-off values of the trace elements and thiol/disulfide hemostasis can be used clinically by physicians in the etiology, diagnosis and treatment of vertigo.

Maternal Epilepsy and Umbilical Cord Blood Oxidative Stress Level

INTRODUCTION

We investigated the effect of epilepsy on cord blood oxidative stress status.

MATERIAL AND METHODS

Thirty (n = 30) pregnant women with epilepsy and thirty (n = 30) healthy controls enrolled in this case control study. Albumin and IMA values and dynamic thiol/disulfide parameters were measured.

RESULTS

Decreased native thiol and total thiol levels were found in the epilepsy group when compared to the control group (p: 0.001, p: 0.002). Higher IMA (p: 0.036) and lower albumin cord levels (P < 0.001) were measured in the epilepsy group with respect to the control group. Apgar scores at 1 and 5 miutes were lower in the epilepsy group (respectively; p = 0.012, p = 0.010). A negative correlation was found between IMA and cord pH value (r = 0.288 p = 0.034).

CONCLUSION

This study showed that epilepsy may alter thiol disulfide homeostasis and IMA levels.

Assessment of dynamic thiol-disulfide homeostasis in patients with lipoid proteinosis (Urbach-Wiethe syndrome)

OBJECTIVE:

Lipoid proteinosis is a rare autosomal recessive genetic dermatological disease that occurs due to the accumulation of hyaline material in the skin and mucous membranes. This study aimed to investigate whether dynamic thiol-disulfide homeostasis is a new marker of oxidative stress in patients suffering from lipoid proteinosis.

METHODS:

The study group involved 17 patients with lipoid proteinosis and 17 healthy controls with same gender and age. Native thiol, total thiol, disulfide levels, and thiol-disulfide indexes were measured with the fully automated spectrophotometric method described by Erel and Neselioglu, and the results of the two groups were statistically analyzed.

RESULTS:

Serum total thiol and native thiol levels were significantly lower in lipoid proteinosis group compared to the control group (p=0.020 and p=0.014, respectively). The disulfide levels were found to be higher in lipoid proteinosis group, but there was no significant difference between two groups.

CONCLUSIONS:

Impaired dynamic thiol-disulfide homeostasis was observed in lipoid proteinosis patients, suggesting that thiol-disulfide homeostasis may have a role in the pathogenesis of this disease.

Oxidative stress and the importance of H. pylori eradication in patients with functional dyspepsia

BACKGROUND

To investigage the thiol and disulphide levels in Helicobacter pylori-positive patients with non-ulcer dyspepsia and investigate the change in these levels with eradication therapy.

METHODS

This is a prospective observational study. A total of 320 patients diagnosed with dyspepsia according to Rome IV criteria were included in the study. First, blood samples were drawn from patients to determine their serum thiol and disulphide levels. Endoscopic biopsy was performed on all patients and the biopsy specimens obtained were examined pathologically. Patients positive for H. pylori were administered eradication therapy. Blood samples were drawn from these patients for the second time, and their serum thiol and disulphide levels were measured. The thiol-disulfide levels of the patients who were successful in H. pylori eradication treatment, with those who were not, were compared before and after the treatment.

RESULTS

The mean plasma disulphide level decreased significantly from 14.0 ± 6.6 to 10.9 ± 5.9 μmol/L in H. pylori-positive patients that responded to the H. pylori eradication treatment (P = 0.033). On the other hand, there was an insignificant increase in the mean serum thiol level (341.4 ± 30.5 vs. 342.6 ± 29.8 μmol/L; P = 0.273) and an insignificant decrease in the mean serum disulphide level (15.2 ± 2.5 vs. 14.8 ± 2.3 μmol/L; P = 0.163) in H. pylori-positive patients that did not respond to the H. pylori eradication treatment.

CONCLUSION

The inflammation caused by H. pylori shifted the thiol-disulphide equilibrium in the cell redox system towards the direction of disulphide. The study findings suggest that the restoration of the said hemostatic balance with eradication therapy relieved the organism from oxidative stress.

Effects of dexmedetomidine on new oxidative stress markers on renal ischaemia-reperfusion injury in rats: thiol/disulphide homeostasis and the ischaemia-modified albumin

OBJECTIVES

This study investigated the effect of dexmedetomidine on the oxidant-antioxidant (thiol/disulphide) balance.

METHODS

A total of 24 rats were divided into four groups. The renal arteries in groups IR (ischaemia/reperfusion) and IR + D (ischaemia/reperfusion + dexmedetomidine) were clamped for 45 min and reperfused for 180 min. Groups D (Dexmedetomidine) and IR + D were administered 100 μg/kg dexmedetomidine. Oxidant-antioxidant (thiol/disulphide) levels were measured. Kidney tissue was examined histopathologically.

RESULTS

No statistically difference was found between the groups in terms of thiol-disulphide averages, while IMA, TOS and thiol-disulphide results showed a minimal decrease in Group IR + D compared to Group IR (p > 0.05). Tubular lesions and necrosis were found in 26-50% of tubules in Group IR. Tubular damage and necrosis in Group IR + D declined to 5-25% .

CONCLUSIONS

No statistically difference was found in the study where OSI index, thiol/disulphide balance and IMA were measured together as biochemical values.

Mice lacking α4 nicotinic acetylcholine receptors are protected against alcohol-associated liver injury

BACKGROUND

Chronic heavy alcohol consumption is a major risk factor for the development of liver steatosis, fibrosis, and cirrhosis, but the mechanisms by which alcohol causes liver damage remain incompletely elucidated. This group has reported that α4 nicotinic acetylcholine receptors (α4 nAChRs) act as sensors for alcohol in lung cells. This study tested the hypothesis that α4 nAChRs mediate the effects of alcohol in the liver.

METHODS

Expression of acetylcholine receptor subunits in mouse liver was determined by RNA sequencing (RNA-seq). α4 nAChR knockout (α4 KO) mice were generated in C57BL/6J mice by introducing a mutation encoding an early stop codon in exon 4 of Chrna4, the gene encoding the α4 subunit of the nAChR. The presence of the inactivating mutation was established by polymerase chain reaction and genomic sequencing, and the lack of α4 nAChR function was confirmed in primary fibroblasts isolated from the α4 KO mice. Wild-type (WT) and α4 KO mice were fed the Lieber-DeCarli diet (with 36% of calories from alcohol) or pair fed an isocaloric maltose-dextrin control diet for a 6-week period that included a ramping up phase of increasing dietary alcohol.

RESULTS

Chrna4 was the most abundantly expressed nAChR subunit gene in mouse livers. After 6 weeks of alcohol exposure, WT mice had elevated serum transaminases and their livers showed increased fat accumulation, decreased Sirt1 protein levels, and accumulation of markers of oxidative stress and inflammation including Cyp2E1, Nos2, Sod1, Slc7a11, TNFα, and PAI1. All these responses to alcohol were either absent or significantly attenuated in α4 KO animals.

CONCLUSION

Together, these observations support the conclusion that activation of α4 nAChRs by alcohol or one of its metabolites is one of the initial events promoting the accumulation of excess fat and expression of inflammatory mediators. Thus, α4 nAChRs may represent viable targets for intervention in chronic alcohol-related liver disease.

How do thiol disulfide balance and copper-ceruloplasmin levels change in women using copper intrauterine devices?

ObjectivesWe 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).MethodThirty-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.ResultsPlasma 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.ConclusionAfter 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.

Comparison of thiol disulfide values in the cord blood of patients undergoing cesarean section under spinal or general anesthesia

Background/Aim: Oxidative stress is known to increase in patients receiving anesthesia before undergoing surgery. Since newborns are more sensitive to oxygen-free radicals, the effects and characteristics of anesthesia methods that are used for pregnant women require analysis. This study aimed to evaluate the effects of spinal and general anesthesia on oxidative stress by investigating thiol disulfide and ischemia modified albumin (IMA) concentrations in the cord blood of patients undergoing cesarean section (C-section) via spinal or general anesthesia. Methods: This cross-sectional prospective study included 60 patients who were indicated for elective cesarean section. Patients with chronic disease, pregnancy complications and/or required emergency cesareans were not included. Group 1 (n = 30) underwent general anesthesia, and Group 2 (n = 30) underwent spinal anesthesia during their C-sections. Thiol–disulfide levels were evaluated concurrently in all blood samples taken from the umbilical artery remaining on the placental side. Results: The mean age (SD) of the mothers was 30.6 (4.4) years and the mean gestational age (SD) was 39.0 (0.9) weeks. Gestational age, birth weight, and first and fifth min Apgar scores of the two groups were similar. The mean (SD) native thiol (362.4 [63.8]; 323.2 [45.8]), total thiol (409.6 [70.2]; 363.5 [46.1]), and disulfide values (23.6 (5.4); 20.2 (4.3)) were significantly higher in group 1 than group 2, while the median (interquartile range [IQR]) values of IMA (0.89 (0.85-max 0.92); 0.85 (min 0.82-max 0.879) were significantly higher in group 2 than group 1 (P < 0.05). Conclusions: As general anesthesia may cause a higher degree of oxidative stress, selecting the appropriate anesthetic technique may be especially important for risky pregnancies in which increased oxidative stress in the mother and baby may be critical for the outcome.

Evaluation of thiol/disulfide hemostasis and serum Ischemia modified albumin as oxidative stress biomarkers in systemic lupus erythematosus patients: Relationship with major organ involvement and disease activity

OBJECTIVES

We aimed to compare thiol/disulfide hemostasis and serum ischemia-modified albumin (IMA) levels, which are indicators of oxidative stress (OS), in patients with systemic lupus erythematosus (SLE), with the healthy control (HC) group and to evaluate the relationship of these parameters with disease activity and major organ involvement.

MATERIAL-METHODS

Eighty-four SLE patients and 96 HCs were included in this study. The disease activity of SLE patients was calculated using The Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K). Patients with SLEDAI-2K ≤ 5 were classified as low disease activity (LDA) and those with SLEDAI-2K > 6 as high disease activity (HDA). Thiol/disulfide hemostasis was evaluated using a new automated method and natural thiol (NT), total thiol (TT), disulfide (SS) levels, SS/NT, SS/TT, NT/TT ratios, and serum IMA levels were recorded.

RESULTS

NT and TT levels were significantly lower (490.11 ± 123.61 vs 536.96 ± 86.05, p = 0.003) (532.56 ± 125.80 vs 565.72 ± 89.82, p = 0.046), SS level (21.22 ± 11.75 vs 13.37 ± 9.31, p < 0.001) was higher, and SS/TT (4.64 ± 2.93 vs 2.52 ± 1.82, p < 0.001) and SS/NT (4.12 ± 2.33 vs 2.35 ± 1.59, p < 0.001) ratios were significantly higher in SLE patients compared to HCs. IMA values were not different between the two groups (p = 0.920). NT (449.84 ± 136.98 vs 520.32 ± 104.11, p = 0.012) and TT levels (492.01 ± 138.45±562.97 ± 107.09, p = 0.013) were significantly lower and serum IMA levels (0.802 ± 0.089 vs 0.764 ± 0.040, p = 0.023) were significantly higher in SLE patients with HDA than in LDA patients. There was a weak negative correlation between NT (r = -0.284, p=0.009) (r = -0.291, p = 0.007) and TT levels (r = -0.281, p = 0.010) (r = -0.289, p = 0.008) and a weak positive correlation between IMA levels (r = 0.279, p = 0.011) (r = 0.263, p = 0.016) and SLEDAI-2K, and major organ involvement.

CONCLUSION

It is thought that thiol/disulfide hemostasis and IMA levels may be used as ideal biomarkers of OS in SLE patients and may reflect the disease activity and major organ involvement.

Evaluation of Salivary Thiol/Disulfide Homeostasis and Oxidative Stress in Children with Severe Early Childhood Caries Using a Novel Method

Objective This study aimed to assess the role of thiol/disulfide homeostasis and oxidative stress in the saliva of children with severe early childhood caries (S-ECC).

Methods Eighty children aged 3 to 6 years were involved in this case-control study. The study consisted of two groups: the study group (S-ECC) and the control group with no caries. Thiol/disulfide homeostasis and antioxidant levels were calculated after obtaining unstimulated saliva samples from all participating children.

Results The native/total thiol and total oxidant status (TOS) levels of the study group were higher than those of the control group, though not statistically significant (p > 0.05). The oxidative stress index (OSI) value was significantly higher in the study group compared to the control group (p = 0.024).

Conclusion Our results confirmed that the thiol/disulfide homeostasis was reduced, and disulfide formation, which is rereducible to thiol, was insufficient in children with S-ECC to compensate oxidative stress compared with the control group. Also, thiol levels were inadequate to compensate for oxidative stress, and thiol/disulfide homeostasis was not an independent parameter for S-ECC. Besides, the increases in the TOS level and OSI value show that oxidative stress had significant effects on S-ECC's etiopathogenesis.

Proptosis is associated with thiol-disulfide in patients with Graves' ophthalmopathy

Objective

Graves' ophthalmopathy (GO) is a vision-threatening finding observed in approximately half of Graves' disease patients. The pathophysiology of GO is unclear, and one of the suspected factors is oxidative stress. In our study, we compared the relationship between proptosis and SH-SS in patients diagnosed with GO.

Methods

In this prospective study, 40 recently diagnosed Graves' disease patients with proptosis, 40 recently diagnosed Graves' disease patients without GO and 30 healthy individuals with similar demographic characteristics were included. Serum thiol-disulfide (SH-SS) measurements were performed. Eye examinations were performed by a single ophthalmologist to check for the presence of GO, and proptosis values were recorded with a Hertel exophthalmometer.

Results

Total SH values were lower in the group with proptosis than in the other groups (p < 0.05). Total and native SH values were lower in patients without proptosis than in the control group (p < 0.05). Total SH, native SH and SS levels were independently associated with proptosis (p < 0.05). According to this analysis, it was found that increasing SS and decreasing total and native SH levels increased the probability of proptosis by 24.4%, 32.7% and 32.4%, respectively.

Conclusion

A decrease in SH, which is a natural antioxidant that protects the body against oxidative stress, and an increase in SS are important signs of oxidative damage. Proptosis and SH-SS are closely related in GO. This may help us detect GO and proptosis in Graves' patients. It can also assist in developing new options for preventing and treating GO.

Pediatric Carbon Monoxide Poisoning: Effects of Hyperbaric Oxygen Therapy on Thiol/Disulfide Balance

OBJECTIVES

Carbon monoxide (CO) poisoning remains the foremost cause of poisoning worldwide. This study aimed to investigate the effects of hyperbaric oxygen therapy (HBOT) and normobaric oxygen therapy (NBOT) on thiol/disulfide homeostasis in children with CO intoxication.

METHODS

Eighty-one children aged 0 to 18 years with CO intoxication were included in this cross-sectional study. No changes were made in the routine clinical evaluation and treatment practices of the patients. Thirty-two children who received HBOT and 49 children who received NBOT were compared for serum native thiol, disulfide, and total thiol levels, as well as for the changes in disulfide/native thiol, disulfide/total thiol, and native thiol/total thiol ratios before and after treatment.

RESULTS

Antioxidant levels, such as native thiol and total thiol, were significantly decreased in patients who received HBOT and increased in those who received NBOT (P = 0.02 and P = 0.01, respectively). There was no statistically significant difference between the 2 groups concerning the change of native thiol/total thiol ratios (P = 0.07). In addition, there was no significant difference regarding changes in disulfide, disulfide/native thiol, and disulfide/total thiol levels before and after treatment (P = 0.39, P = 0.07, and P = 0.07, respectively).

CONCLUSIONS

Although thiol-disulfide balance is maintained in patients treated with HBOT, antioxidant levels decrease significantly compared with NBOT. Despite efficiency of HBOT in CO intoxication, oxidative stress and reperfusion injury due to hyperoxygenation should be considered in the treatment of HBOT.

Thiols and disulfide levels are correlated with TIMI thrombus grade in non-ST elevation myocardial infarction patients

Aim: We investigated the relationship between thrombolysis in myocardial infarction (TIMI) thrombus grade and thiol/disulfide levels. Materials & methods: 182 non-ST elevation myocardial infarction (NSTEMI) patients were divided into two groups; TIMI grade 0 patients who do not have any visible thrombus in their culprit vessels, and TIMI thrombus grade 1-5 patients. Results: Native and total thiol levels and disulfide to thiol ratio were higher in the low thrombus group. In addition, thrombus grade was positively correlated with disulfide to native and total thiol ratio and negatively with native and total thiol levels in NSTEMI patients. Conclusion: We can assert that thiol levels tend to decrease, and the disulfide to thiol ratio increase with increasing thrombus burden in NSTEMI patients.

NRF2-Dependent Placental Effects Vary by Sex and Dose following Gestational Exposure to Ultrafine Particles

Exposure to ultrafine particles (UFPs, PM0.1) during pregnancy triggers placental oxidative stress and inflammation, similar to fine PM (PM2.5). The Nrf2 gene encodes a redox-sensitive transcription factor that is a major regulator of antioxidant and anti-inflammatory responses. Disruption of NRF2 is known to substantially enhance PM2.5-driven oxidant and inflammatory responses; however, specific responses to UFP exposure, especially during critical windows of susceptibility such as pregnancy, are not fully characterized; To investigate the role of NRF2 in regulating maternal antioxidant defenses and placental responses to UFP exposure, wildtype (WT) and Nrf2-/- pregnant mice were exposed to either low dose (LD, 100 µg/m3) or high dose (HD, 500 µg/m3) UFP mixture or filtered air (FA, control) throughout gestation; Nrf2-/- HD-exposed female offspring exhibited significantly reduced fetal and placental weights. Placental morphology changes appeared most pronounced in Nrf2-/- LD-exposed offspring of both sexes. Glutathione (GSH) redox analysis revealed significant increases in the GSH/GSSG ratio (reduced/oxidized) in WT female placental tissue exposed to HD in comparison with Nrf2-/- HD-exposed mice. The expression of inflammatory cytokine genes (Il1β, Tnfα) was significantly increased in Nrf2-/- placentas from male and female offspring across all exposure groups. Genes related to bile acid metabolism and transport were differentially altered in Nrf2-/- mice across sex and exposure groups. Notably, the group with the most marked phenotypic effects (Nrf2-/- HD-exposed females) corresponded to significantly higher placental Apoa1 and Apob expression suggesting a link between placental lipid transport and NRF2 in response to high dose UFP exposure; Disruption of NRF2 exacerbates adverse developmental outcomes in response to high dose UFP exposure in female offspring. Morphological effects in placenta from male and female offspring exposed to low dose UFPs also signify the importance of NRF2 in maternal-fetal response to UFPs.

NRF2 Protects against Altered Pulmonary T Cell Differentiation in Neonates Following In Utero Ultrafine Particulate Matter Exposure

Early life exposure to particulate matter (PM) air pollution negatively impacts neonatal health. The underlying mechanisms following prenatal exposure, particularly to ultrafine particles (UFP, diameter ≤ 0.1 μm), are not fully understood; To evaluate the role of Nrf2 in response to in utero UFP exposure, we exposed time-mated Nrf2-deficient (Nrf2-/-) or wildtype (WT) mice to filtered air (FA) or 100 μg/m3 ultrafine PM daily throughout pregnancy. Offspring were evaluated for pulmonary immunophenotypes and pulmonary/systemic oxidative stress on postnatal day 5, a timepoint at which we previously demonstrated viral respiratory infection susceptibility; Nrf2-/- offspring exposed to FA had significantly lower average body weights compared to FA-exposed WT pups. Moreover, PM-exposed Nrf2-/- offspring weighed significantly less than PM-exposed WT pups. Notably, PM-exposed Nrf2-/- offspring showed a decreased pulmonary Th1/Th2 ratio, indicating a Th2 bias. Th17 cells were increased in FA-exposed Nrf2-/- neonates yet decreased in PM-exposed Nrf2-/- neonates. Analysis of oxidative stress-related genes in lung and oxidative stress biomarkers in liver tissues did not vary significantly across exposure groups or genotypes. Collectively, these findings indicate that the lack of Nrf2 causes growth inhibitory effects in general and in response to gestational UFP exposure. Prenatal UFP exposure skews CD4+ T lymphocyte differentiation toward Th2 in neonates lacking Nrf2, signifying its importance in maternal exposure and infant immune responses.

Evaluation of Oxidative Stress in Ectopic Pregnancies

PURPOSE

The aim of the study is to show the relationship between oxidative stress and ectopic pregnancy.

MATERIALS AND METHODS

A total of 62 patients, 31 in the ectopic pregnancy group (study group) and 31 in the first-trimester pregnancy (control group) were included in the study. Patients between 18-45 years of age who had tubal ectopic pregnancy diagnosed by transvaginal ultrasonography and serum β-HCG values were included in the study group. Serum thiol- disulfide hemostasis were measured from venous blood.

RESULTS

Between the control group and the ectopic pregnant group; there was no statistically significant difference in terms of age, total thiol, albumin, disulfide, index 1 (disulfide / total thiol), index 2 (disulfide / native thiol), and index 3 levels (p> 0.05). The area under the ROC curve for native thiol measurements was statistically significant in distinguishing the control group and the ectopic pregnant group [AUC = 0.657, 95% CI: 0.521-0.793, p = 0.034] Conclusion: This study shows that ectopic pregnancies may be associated with the presence of high oxidative stress. Especially in early stage suspected patients, demonstrating the presence of oxidative stress together with serial β-HCG follow-up may be helpful in diagnosis.

Role of Biomarkers as Prognostic Factors in Acute Peripheral Facial Palsy

Acute peripheral facial palsy (APFP), including Bell's palsy and Ramsay Hunt syndrome, is a disease that affects daily life through facial motor dysfunction, causing psychological problems. Various tests to evaluate prognosis have been studied; however, there are no validated predictive biomarkers to guide clinical decision making. Therefore, specific biomarkers that respond to treatment are required to understand prognostic outcomes. In this review, we discuss existing literature regarding the role of APFP biomarkers in prognosis and recovery. We searched the PubMed, EMBASE, and Cochrane Library databases for relevant papers. Our screening identified relevant studies and biomarkers correlating with the identification of predictive biomarkers. Only studies published between January 2000 and October 2021 were included. Our search identified 5835 abstracts, of which 35 were selected. All biomarker samples were obtained from blood and were used in the evaluation of disease severity and prognosis associated with recovery. These biomarkers have been effective prognostic or predictive factors under various conditions. Finally, we classified them into five categories. There is no consensus in the literature on the correlation between outcomes and prognostic factors for APFP. Furthermore, the correlation between hematologic laboratory values and APFP prognosis remains unclear. However, it is important to identify new methods for improving the accuracy of facial paralysis prognosis prediction. Therefore, we systematically evaluated prognostic and potentially predictive APFP biomarkers. Unfortunately, a predictive biomarker validating APFP prognosis remains unknown. More prospective studies are required to reveal and identify promising biomarkers providing accurate prognosis.

The role of protein oxidation in the development of diabetic microvascular complications

OBJECTIVE

The role of protein oxidation in the development of diabetic microvascular complications was investigated.

METHODS

In total, 266 participants were split into five groups: Group 1; diabetes mellitus for at least 10 years without any complications, Group 2; diabetic nephropathy, Group 3; diabetic neuropathy, Group 4; diabetic retinopathy, and Group 5; control group. Thiol, disulfide, ferroxidase, and ischemia-modified albumin (IMA) levels were analyzed in the serum.

RESULTS

Native thiol, total thiol, and native thiol/total thiol were lower in Group 4 than Groups 1, 3, and 5 (p<0.001). However, disulfide/native thiol and disulfide/total thiol were higher in Group 4 than all other groups (p<0.001). IMA was higher in Groups 3 and 4 than all other groups (p<0.001). Ferroxidase was lower in Groups 3 and 4 than Group 2 (p<0.001).

CONCLUSION

Thiol-disulfide homeostasis impairment in favor of disulfide may have a function in the progress of diabetic retinopathy. Furthermore, the disruptions of IMA and ferroxidase levels involve in the development of diabetic retinopathy and neuropathy.

Assessing Oxidative Stress by Thiol/Disulfide Homeostasis Among Vitamin D-Deficient Patients

Objective: Thiol/disulfide (T/DS) homeostasis represents a promising new approach to evaluate oxidative stress. Therefore, we aimed to examine T/DS homeostasis in vitamin D (VitD)-deficient patients.

Methods: We enrolled 154 patients with VitD deficiency and 154 healthy control subjects in the study. For both groups, native thiol, total thiol, and disulfide values were measured. Additionally, considering the obtained 25-hydroxycholecalciferol [25(OH)D] levels, the patient group was further divided into two subgroups (Group 1: <10 ng/mL, Group 2: 10-20 ng/mL), which were compared in more depth according to the specified parameters.

Results: Values of native thiol, total thiol, and disulfide measured in the combination of Groups 1 and 2, comprising individuals with VitD deficiency, proved to be higher in comparison to the control group with statistical significance (p=0.007, p=0.028, and p<0.001, respectively). When subgroups were considered according to VitD classifications, native thiol and total thiol were again higher in Group 1 in comparison to the values obtained for control subjects (p=0.022; p<0.001). While the total thiol level of Group 2 was higher than that of controls (p<0.001), no difference with statistical significance was obtained in the comparison of disulfide levels among the indviduals of Group 1, Group 2, and the controls (p=0.081).

Conclusion: In this study, among patients with VitD deficiency, we have confirmed that values of native thiol and total thiol were increased, while the T/DS balance was found to have shifted in favor of the thiol level.

Dynamic thiol/disulphide balance in patients undergoing hypotensive anesthesia in elective septoplasties

OBJECTIVE

We aimed to investigate the effects of hypotensive anaesthesia on oxidative stress with serum thiol/disulphide balance in patients undergoing elective septoplasty procedures under general anaesthesia.

METHODS

Seventy-two patients between the ages of 18-60, with a physical condition I -II, according to the American Society of Anesthesiologists, were included in this prospective observational study. Septoplasty was chosen for standard surgical stress. According to the maintenance of anaesthesia, patients were divided into the groups as Hypotensive Anaesthesia (n = 40) and Normotensive Anaesthesia (n = 32). Serum thiol/disulphide levels were measured by the method developed by Erel & Neşelioğlu.

RESULTS

The native thiol and total thiol values of both groups measured at the 60th min intraoperatively were significantly lower than the preoperative values (both P < .01). Intraoperatively, at the 60th min, there was no significant difference in terms of post-native thiol and post-total thiol levels between hypotensive and normotensive anaesthesia groups (P = .68 and .81, respectively). Age >40 years and female gender were found to have a significant effect on dynamic oxidative stress (P = .002 and .001, respectively).

CONCLUSION

This pilot study has found that hypotensive anaesthesia had no adverse effect on dynamic thiol/disulphide balance in elective surgeries.

Evaluation of Thiol Homeostasis in Multiple Sclerosis and Neuromyelitis Optica Spectrum Disorders

Objectives: The aim of this pilot study was to evaluate dynamic thiol-disulfide homeostasis as a novel oxidative stress parameter in multiple sclerosis (MS), neuromyelitis optica spectrum disorders (NMOSD), and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) to better understand the role of thiol homeostasis in neuroimmunological diseases.

Methods: A total of 85 participants were included in this study, consisting of 18 healthy controls, 52 patients diagnosed with MS, seven with NMOSD, and eight with MOGAD. We measured total thiol (–SH+-S–S–) and native thiol (–SH) levels in the serum of all the participants, and in a subset of patients (n = 11), these parameters were investigated in paired cerebrospinal fluid (CSF) and serum samples. Dynamic disulfide concentrations were calculated separately. Finally, we determined if there was any relationship between clinical features and dynamic thiol homeostasis.

Results: There was a statistically significant difference between serum and CSF levels of biomarkers of thiol homeostasis. Serum total thiol (317.88 ± 66.04) and native thiol (211.61 ± 44.15) levels were significantly lower in relapsed patients compared to those in remission (368.84 ± 150.36 vs. 222.52 ± 70.59, respectively).

Conclusions: Oxidative stress plays a crucial role in the physiopathology of neuroimmunological diseases. Thiol homeostasis may be useful for monitoring disease activity.

Serum Thiol Levels and Thiol/Disulfide Homeostasis in Patients with Rheumatic Mitral Valve Disease and Healthy Subjects

Fundamento

A doença valvar mitral reumatismal (DVMR) é a apresentação mais comum das doenças cardíacas reumáticas (DCR). Os processos de inflamação e fibrose também têm papéis significativos em sua patogênese. Estudos recentes demonstram que os tióis e o tiol-dissulfeto são marcadores de stress oxidativo inéditos e promissores.

Objetivos

O objetivo deste estudo foi avaliar diferenças entre os níveis de tiol sérico e de tiol-dissulfeto em pacientes com DVMR e no grupo de controle.

Métodos

Noventa e dois pacientes com DVMR foram cadastrados no estudo. Cinquenta e quatro sujeitos saudáveis, e com correspondência de sexo e idade em relação ao grupo de estudo, também foram incluídos no estudo como um grupo de controle. Foram investigados os níveis de tiol nos pacientes com DVMR e o grupo de controle. Os p-valores menores que 0,05 foram considerados estatisticamente significativos.

Resultados

Os pacientes com DVMR apresentaram pressão sistólica da artéria pulmonar (PSAP) e níveis de diâmetro do átrio esquerdo (AE) mais altos que os do grupo de controle. Os níveis de tiol nativo (407±83 μmol/L vs. 297±65 μmol/L, p<0,001) e tiol total (442±82 μmol/L vs. 329±65 μmol/L, p<0,001) são mais altos no grupo de controle. Níveis de dissulfeto (16,7±4,9 μmol/L vs. 14,8±3,7 μmol/L, p=0,011) são mais altos no grupo de pacientes com DVMR. Foi identificada uma correlação positiva entre as razões dissulfeto/tiol nativo e dissulfeto/tiol total com PSAP, diâmetro de AE, e gravidade da EMi. A razão dissulfeto/tiol total é significativamente mais alta em pacientes com EMi grave que em pacientes com EMi leve a moderada.

Conclusões

Até onde se sabe, este é o único estudo que avaliou a homeostase tiol/dissulfeto como um preditor inédito, que está relacionado de forma mais próxima à DVMR e à gravidade da EMi.

Na/H Exchange Regulatory Factor 1 Deficient Mice Show Evidence of Oxidative Stress and Altered Cisplatin Pharmacokinetics

(1) Background: One third of patients who receive cisplatin develop an acute kidney injury. We previously demonstrated the Na/H Exchange Regulatory Factor 1 (NHERF1) loss resulted in increased kidney enzyme activity of the pentose phosphate pathway and was associated with more severe cisplatin nephrotoxicity. We hypothesized that changes in proximal tubule biochemical pathways associated with NHERF1 loss alters renal metabolism of cisplatin or response to cisplatin, resulting in exacerbated nephrotoxicity. (2) Methods: 2-4 month-old male wild-type and NHERF1 knock out littermate mice were treated with either vehicle or cisplatin (20 mg/kg dose IP), with samples taken at either 4, 24, or 72 h. Kidney injury was determined by urinary neutrophil gelatinase-associated lipocalin and histology. Glutathione metabolites were measured by HPLC and genes involved in glutathione synthesis were measured by qPCR. Kidney handling of cisplatin was assessed by a kidney cortex measurement of γ-glutamyl transferase activity, Western blot for γ-glutamyl transferase and cysteine S-conjugate beta lyase, and ICP-MS for platinum content. (3) Results: At 24 h knock out kidneys show evidence of greater tubular injury after cisplatin and exhibit a decreased reduced/oxidized glutathione ratio under baseline conditions in comparison to wild-type. KO kidneys fail to show an increase in γ-glutamyl transferase activity and experience a more rapid decline in tissue platinum when compared to wild-type. (4) Conclusions: Knock out kidneys show evidence of greater oxidative stress than wild-type accompanied by a greater degree of early injury in response to cisplatin. NHERF1 loss has no effect on the initial accumulation of cisplatin in the kidney cortex but is associated with an altered redox status which may alter the activity of enzymes involved in cisplatin metabolism.

The relationship between serum thiol levels and thiol/disulfide homeostasis in women with tubal ectopic pregnancy

OBJECTIVE

The aim of this study was to investigate the thiol/disulfide homeostasis in tubal ectopic pregnancies in terms of early diagnosis of the disease.

DESIGN

A prospective case-control study was carried out between June 2017-February 2018 in the Gynaecology Department of Umraniye Medical and Research Hospital.

MATERIALS AND METHODS

A total of 42 women with ectopic pregnancy were compared with 44 healthy women who have intrauterine first trimester pregnancies. The thiol/disulfide homeostasis is evaluated with the spectrophotometric measurement method that was recently developed by Erel&Neselioglu.

RESULTS

Disulfide/native thiol and disulfide/total thiol ratios were increased (p = 0.018 and p = 0.023 respectively), while native thiol/total thiol ratios and native thiol levels were decreased in tubal ectopic pregnancy group according to control group (p = 0.023). Between control and tubal ectopic pregnancy groups no differences were measured in disulfide levels (p = 0.350). The area under curve for native thiol and total thiol were 0.937 and 0.927, respectively. The optimum cut off value for native thiol was 379.95 μmol/l with a sensitivity of 90% and specificity of 81%. The optimum cut off value for total thiol was 432.5 μmol/l had 92% sensitivity and 79% specificity.

LIMITATIONS

In the study, whether intrauterine pregnancies resulted in miscarriage or delivery can be examined.

CONCLUSION

Increased disulfide/native thiol levels, disulfide/total-thiol ratio and decreased native/total thiol ratio were found to be significantly associated with the presence of tubal ectopic pregnancy which can be useful for the early diagnosis of the disease.

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.

Evaluation of thiol/disulphide balance in patients with cutaneous leishmaniasis

OBJECTIVE

The aim of this study was to evaluate serum thiol disulphide levels in patients with cutaneous leishmaniasis (CL) compared with a healthy control group and to investigate whether thiol/disulphide balance can be used as a new marker of oxidative stress in CL patients.

MATERIAL AND METHODS

This prospective study included 47 patients diagnosed with CL and 46 healthy individuals without any disease. Native thiol, disulphide and total thiol levels were used in plasma. Disulphide/total thiol, disulphide/native thiol and native thiol/total thiol levels were measured.

RESULTS

Disulphide, native thiol disulphide and total thiol disulphide levels were significantly lower in CL patients compared with the control group. However, there was no statistically significant difference between CL patients and the control group in terms of disulphide/native thiol, disulphide/total thiol and native thiol/total thiol values.

CONCLUSION

Based on the data in our study, it can be said that the use of thiol/disulphide balance as a new oxidative stress marker in CL patients is not appropriate, but studies with a larger number of patients are needed.

The age-dependent decline of the extracellular thiol-disulfide balance and its role in SARS-CoV-2 infection

SARS-CoV-2 (COVID-19) infection can cause a severe respiratory distress syndrome. The risk of severe manifestations and mortality characteristically increase in the elderly and in the presence of non-COVID-19 comorbidity. We and others previously demonstrated that the low molecular weight (LMW) and protein thiol/disulfide ratio declines in human plasma with age and such decline is even more rapid in the case of inflammatory and premature aging diseases, which are also associated with the most severe complications of COVID-19 infection. The same decline with age of the LMW thiol/disulfide ratio observed in plasma appears to occur in the extracellular fluids of the respiratory tract and in association with many pulmonary diseases that characteristically reduce the concentrations and adaptive stress response of the lung glutathione. Early evidence in literature suggests that the thiol to disulfide balance of critical Cys residues of the COVID-19 spike protein and the ACE-2 receptor may influence the risk of infection and the severity of the disease, with a more oxidizing environment producing the worst prognosis. With this hypothesis paper we propose that the age-dependent decline of LMW thiol/disulfide ratio of the extracellular fluids, could play a role in promoting the physical (protein-protein) interaction of CoV-2 and the host cell in the airways. Therefore, this redox-dependent interaction is expected to affect the risk of severe infection in an age-dependent manner. The hypothesis can be verified in experimental models of in vitro CoV-2 infection and at the clinical level in that LMW thiols and protein thiolation can now be investigated with standardized, reliable and versatile laboratory protocols. Presenting the verification strategy of our hypothesis, we also discuss available nutritional and ancillary pharmacological strategies to intervene on the thiol/disulfide ratio of extracellular fluids of subjects at risk of infection and COVID-19 patients.

Thiol-disulphide homoeostasis as a novel oxidative stress biomarker in lung tuberculosis patient

AIMS OF STUDY

To compare a novel oxidative stress biomarker dynamic thiol/disulphide homoeostasis between patients with lung tuberculosis and healthy controls.

METHODS

Our study included 50 patients with active lung tuberculosis and 50 healthy controls. Serum thiol/disulphide was measured with a new automated spectrometric method developed and results were compared statistically.

RESULTS

We found that native and total thiol levels were significantly decreased in patients with lung tuberculosis, disulphide/native thiol and disulphide/total thiol levels were found to be higher in lung tuberculosis patients when compared with the control group. However, disulphide levels were higher in the control group than in the patient group.

CONCLUSIONS

Based on the results of this study, it can be said that oxidative stress is closely associated with lung tuberculosis pathogenesis. There is a need for new studies that will show the possible effects of oxidative stress on lung tuberculosis pathogenesis.

Effects of the hydroalcoholic extract of Rosa damascena on hippocampal long-term potentiation in rats fed high-fat diet

High-fat diets (HFDs) and obesity can cause serious health problems, such as neurodegenerative diseases and cognitive impairments. Consumption of HFD is associated with reduction in hippocampal synaptic plasticity. Rosa damascena (R. damascena) is traditionally used as a dietary supplement for many disorders. This study was carried out to determine the beneficial effect of hydroalcoholic extract of R. damascena on in vivo hippocampal synaptic plasticity (long-term potentiation, LTP) in the perforant pathway (PP)-dentate gyrus (DG) pathway in rats fed with an HFD. Male Wistar rats were randomly assigned to four groups: Control, R. damascena extract (1 g/kg bw daily for 30 days), HFD (for 90 days) and HFD + extract. The population spike (PS) amplitude and slope of excitatory post-synaptic potentials (EPSP) were measured in DG area in response to stimulation applied to the PP. Serum oxidative stress biomarkers [total thiol group (TTG) and superoxide dismutase (SOD)] were measured. The results showed the HFD impaired LTP induction in the PP-DG synapses. This conclusion is supported by decreased EPSP slope and PS amplitude of LTP. R. damascena supplementation in HFD animals enhanced EPSP slope and PS amplitude of LTP in the granular cell of DG. Consumption of HFD decreased TTG and SOD. R. damascena extract consumption in the HFD animals enhanced TTG and SOD. These data indicate that R. damascena dietary supplementation can ameliorate HFD-induced alteration of synaptic plasticity, probably through its significant antioxidant effects and activate signalling pathways, which are critical in controlling synaptic plasticity.