Evaluation of Glutathione (GSH) System in Porcine Saliva: Validation and Application of Colorimetric Method.

(1) Reduced glutathione (GSH) is considered the first line of antioxidant defense. During oxidative stress, it is oxidized to glutathione disulphide (GSSG). (2) A simple and quick spectrophotometric method based on sodium borohydride (NaBH4) as a reductant to measure the total and reduced GSH in porcine saliva was analytically validated and evaluated in two situations in this species: (a) in a physiological situation, involving sows during the late lactation and post-weaning periods, and (b) in a situation of sepsis in pigs experimentally induced by LPS administration. (3) The results of the analytical validation showed that the assay was precise and accurate in the porcine saliva samples. Higher total GSH and GSSG and lower reduced GSH were observed in the saliva of sows during the post-weaning period, as well as in pigs with experimentally induced sepsis. (4) In conclusion, the validated assay showed adequate analytical results and could be used to evaluate the GSH system of porcine saliva, as demonstrated during the clinical performance.

Determination of thiol-disulphide homeostasis in premenstrual syndrome during adolescence.

BACKGROUND: Premenstrual syndrome (PMS) characterized by cyclic symptoms during the luteal phase of the menstrual cycle, presents an uncertain etiology in adolescents involving hormonal fluctuations and serotonin-related neurotransmitters with a limited existing literature on the impact of oxidative stress. This study aimed to explore the potential association between PMS and oxidative stress in adolescents. METHODS: In a cross-sectional study conducted at a university hospital, involving 45 adolescent girls aged 12 to 18, participants were categorized based on the presence or absence of PMS using the cut-off point of 110 on the PMS Scale developed by Gençdogan. Oxidative stress was assessed through dynamic thiol-disulfide homeostasis. The shift from the balance towards disulfide form is associated with oxidative stress, whereas towards thiol it shows a greater antioxidant capacity. RESULTS: Thirty out of the forty-five participants were found to have PMS with a mean age of 15.5 years. The PMS group demonstrated a significant increase in antioxidant markers, specifically elevated native (631.6±57.55 vs 598.2±41.08, p=0.048) and total thiol levels (675.15±3.4 vs 639.3±44.9, p=0.031). Despite a significant increase in thiol, thiol to disulfide ratio was not found to be significant (p=0.849). CONCLUSION: Contradictory to other studies in adults, we have demonstrated an increase in the antioxidant markers in adolescents with PMS. Elevated antioxidant status in adolescents with PMS may be an adaptive response to acute cyclic inflammation in the adolescent period, which might decrease with the progression of age. Further research is needed to investigate the complex interaction between oxidative stress and PMS across different age groups.

Assessment of thiol-disulfide and glutathione homeostasis after levothyroxine replacement in individuals with autoimmune or nonautoimmune hypothyroidism.

Objective: Thyroid hormones are known to affect the biosynthesis and degradation of antioxidant compounds, suggesting a possible link between hypothyroidism and oxidative stress. However, there is no clear consensus in the literature regarding this association. The aim of this study was to evaluate oxidative stress markers (extracellular thiol-disulfide homeostasis and intracellular glutathione homeostasis) in patients with hypothyroidism due to autoimmune (Hashimoto's thyroiditis) or nonautoimmune thyroid disease rendered euthyroid after levothyroxine replacement. Subjects and methods: The study included 116 patients admitted to the Taksim Training and Research Hospital (Istanbul, Türkiye). Of these, 50 had hypothyroidism due to Hashimoto's thyroiditis (HT group), 30 had nonautoimmune hypothyroidism (NAIH group), and 36 were healthy controls (control group). All participants were women. Extracellular thiol-disulfide homeostasis and intracellular glutathione homeostasis tests were assessed as oxidative stress markers. Results: Thiol-disulfide homeostasis in both HT and NAIH groups was shifted toward the oxidative spectrum. Compared with the control group, the HT and NAIH groups had lower levels of native (p < 0.001 and p = 0.001, respectively) and total (p = 0.002 and p = 0.012, respectively) thiol, as well as a lower native thiol/total thiol ratio (p < 0.001 for both). The HT group also had higher disulfide levels than the control group (p = 0.027). Reduced glutathione (GSH) and oxidized glutathione (GSSG) values were comparable across all three groups, but the HT and NAIH groups had higher GSSG/GSH (p < 0.001 for both) and GSSG/(GSH+GSSG) ratios (p = 0.003 and p = 0.005, respectively), along with lower GSH/(GSH+GSSG) ratio (p = 0.001 and p = 0.002, respectively) than the control group. Conclusion: Levothyroxine replacement was ineffective in ameliorating oxidative stress in patients with hypothyroidism due to Hashimoto's thyroiditis or nonautoimmune causes, as extracellular thiol-disulfide homeostasis was notably altered in these patients compared with healthy controls. The findings of this study suggest that oxidative stress remains a prevailing issue in patients with autoimmune or nonautoimmune hypothyroidism even after euthyroidism is restored.

The Effect of Glutathione on Development and Prognosis in Non-Muscle-Invasive Bladder Cancer.

Background: Glutathione, along with its related enzymes, constitutes a key antioxidant defense mechanism against oxidative stress and cancer formation in the body. Among urological malignancies, bladder cancer ranks second following prostate cancer. Oxidative stress has significant involvement in the development and prognosis of bladder cancer. This investigation aimed to examine the impact of glutathione on prognosis in patients with non-muscle-invasive bladder cancer. Methods: This study included 98 patients with high grade non-muscle-invasive bladder cancer who had undergone intravesical Bacillus Calmette-Guérin therapy and 30 healthy controls with no history of uroepithelial carcinoma of the bladder. The patients with bladder cancer were evaluated in three subgroups. Group 1 consisted of 41 patients who did not experience recurrence during follow-up, Group 2 included 28 patients who had recurrent tumors, and Group 3 consisted of 29 patients who progressed to muscle-invasive stages. Blood samples were collected from all participants. Blood levels of reduced, oxidized, and total glutathione were measured spectrophotometrically. Results: Reduced glutathione levels significantly differed among the groups (p < 0.001), attributed to the control group exhibiting higher reduced glutathione levels compared with Groups 1, 2, and 3 (p < 0.001). There were no significant differences in reduced glutathione levels between Groups 1 and 2, Groups 1 and 3, or Groups 2 and 3 (p > 0.05). Total glutathione levels varied significantly among the groups (p < 0.001), with the control group having higher levels than Groups 1, 2, and 3 (p < 0.001). No significant differences were detected between any of the paired patient groups in terms of total glutathione levels (p > 0.05). Regarding oxidized glutathione levels, the difference was statistically significant (p < 0.001), with the control group showing lower levels than the remaining three groups (p < 0.001). Paired comparisons revealed no significant differences in oxidized glutathione levels (p > 0.05). Conclusions: This study revealed that glutathione had an effect on the emergence of bladder cancer but did not affect its prognosis. Nevertheless, we recommend that future studies with larger bladder cancer patient cohorts should be conducted to comprehensively determine the impact of glutathione on the prognosis of this cancer.

Enhanced SELEX Platforms for Aptamer Selection with Improved Characteristics: A Review.

This review delves into the advancements in molecular recognition through enhanced SELEX (Systematic Evolution of Ligands by Exponential Enrichment) platforms and post-aptamer modifications. Aptamers, with their superior specificity and affinity compared to antibodies, are central to this discussion. Despite the advantages of the SELEX process-encompassing stages like ssDNA library preparation, incubation, separation, and PCR amplification-it faces challenges, such as nuclease susceptibility. To address these issues and propel aptamer technology forward, we examine next-generation SELEX platforms, including microfluidic-based SELEX, capillary electrophoresis SELEX, cell-based aptamer selection, counter-SELEX, in vivo SELEX, and high-throughput sequencing SELEX, highlighting their respective merits and innovations. Furthermore, this article underscores the significance of post-aptamer modifications, particularly chemical strategies that enhance aptamer stability, reduce renal filtration, and expand their target range, thereby broadening their utility in diagnostics, therapeutics, and nanotechnology. By synthesizing these advanced SELEX platforms and modifications, this review illuminates the dynamic progress in aptamer research and outlines the ongoing efforts to surmount existing challenges and enhance their clinical applicability, charting a path for future breakthroughs in this evolving field.

Preliminary results of clinical, biochemical, and radiological investigation into the oxidative status in patients with rotator cuff tendinopathy.

We investigated oxidative status in patients with rotator cuff tendinopathy (RCT) and evaluated their relationship with radiological and clinical parameters. In this cross-section study, 88 patients with RCT (59 males and 29 females) and 86 healthy controls (66 males, 20 females) were enrolled. The sample consisted of nontraumatic patients who are suffering from shoulder pain because of rotator cuff disease, which was established by clinical tests and MRI scanning. Oxidative stress in patients with RCT was analyzed via the dynamic thiol/disulfide homeostasis (TDH). Thiol/disulfide homeostasis was measured by a new colorimetric method. Furthermore, oxidative stress was indirectly measured by serum total oxidant status (TOS), oxidative stress index (OSI), and total antioxidant capacity (TAC). Serum disulfide levels and the other oxidative stress parameters of the RCT group were significantly greater than those of the control group (P < .001 for all), whereas the anti-oxidative stress parameters remained unchanged (P > .05 for all). The lowest and highest serum disulfide levels were detected in patients with grades 1 and 3, respectively (P < .001). Furthermore, in a multiple regression analysis, the disulfide/natural thiol ratio (ß=-4.886, P = .004) and the MRI grading (ß=0.314, P=.001) were independently associated with the Western Ontario Rotator Cuff Index WORC score. We found an association between the levels of various serum markers of oxidative injury, especially serum disulfide levels, and the increasing severity of RCT. Thiol/disulfide homeostasis seems to play a critical role in RCT, both in the beginning and during the progression of disease.

Thiol/Disulfide Ratios, HOMA Score, and Quality of Sleep in Renal Transplant Recipients Without Diabetes.

OBJECTIVES: Thiols play an important role in defense against reactive oxygen species. We aimed to evaluate the relation between oxidative stress, glucose tolerance, and sleep quality in kidney transplant recipients without diabetes. MATERIALS AND METHODS: We enrolled 95 kidney transplant recipients without diabetes from living and deceased donors with stable allograft function and 60 healthy controls. We included recipients who received a kidney from a living donor with a first-degree relation. Insulin resistance was determined using the Homeostasis Model Assessment score. Native thiol, total thiol, and disulfide levels were measured, and disulfide versus native thiol/total thiol ratios were calculated from all patients. We used the Pittsburg Sleep Quality Index to assess sleeping patterns. According to standard cutoff value of the index (≤5 indicates good quality sleep; >5 indicates poor sleep quality), we stratified kidney transplant recipients as group 1 (Pittsburg Sleep Quality Index ≤5; n = 41) and group 2 (Pittsburg Sleep Quality Index >5; n = 54). RESULTS: In correlation analysis, Pittsburg Sleep Quality Index was positively correlated with age, the Homeostasis Model Assessment score, body mass index, serum disulfide levels, disulfide/total thiol ratio, and native/total thiol ratio. The Pittsburgh Sleep Quality Index was negatively correlated with total thiol levels. In subgroup analysis, the Homeostasis Model Assessment score, disulfide levels, and disulfide/total thiol and native/total thiol ratios were significantly lower in group 1; however, total thiol level was significantly higher in this group. In multivariate regression analysis, age, the Homeostasis Model Assessment score, disulfide/total thiol ratio, and renal resistivity index were detected as predictors of sleep quality score. CONCLUSIONS: Sleep quality moderates oxidative stress identified by thiol-disulfide homeostasis and insulin resistance in renal transplant recipients without diabetes.

Oxidative Stress in Patients With Melasma: An Evaluation of the Correlation of the Thiol/Disulfide Homeostasis Parameters and Modified MASI Score.

Melasma is a common acquired hyperpigmentation disorder that affects mostly women and individuals with darker skin types. Oxidative stress may play a role in the pathogenesis of melasma. Dynamic thiol/disulfide homeostasis is one of the most important indicators of oxidative stress. This study aimed to investigate the presence of oxidative stress in patients with melasma by evaluating thiol/disulfide homeostasis. Sixty-seven patients with melasma and 41 healthy age- and sex-matched controls were included in the study. Disease severity was evaluated using the modified melasma area and severity index (mMASI). Thiol/disulfide homeostasis parameters of the melasma and control groups were measured using a novel, fully automated spectrophotometric method. Our data indicated the presence of oxidative stress in melasma, which may be correlated with disease severity. Because research on the presence of oxidative stress in melasma is limited, further studies are needed to support these conclusions.

The association of umbilical cord blood oxidative stress with maternal iron deficiency anemia: A tertiary center experience.

OBJECTIVE: To compare the levels of oxidative stress markers in the umbilical cord blood between pregnant women diagnosed with iron deficiency anemia (IDA) and low-risk controls. METHODS: The sample consisted of 131 patients, including 55 pregnant women with IDA and 76 controls with similar demographic characteristics. Participants were selected from patients delivered at ≥37 weeks. We compared the two groups in terms of the native thiol, total thiol, disulfide, and ischemia-modified albumin (IMA) levels measured in pregnant women's umbilical cord venous blood. RESULTS: The native thiol and total thiol values were statistically significantly lower in the anemia group, and the disulfide and IMA values were statistically significantly higher in the IDA group (P < 0.001). Perinatal outcomes were similar between the groups. CONCLUSION: In the present study, pregnant women with IDA had lower native and total thiol values and higher disulfide and IMA values in umbilical cord blood. Iron deficiency anemia in pregnancy may be a potential cause of increased oxidative stress.

Investigation of Thiol/Disulfide Homeostasis and Clinical Parameters in Rosacea Patients According to Skin Subtypes.

Background/Objective: The aim of this study was to compare thiol/disulfide homeostasis and clinical parameters of rosacea patients across skin subtypes of the disease and healthy controls. Methods: This prospective study included 90 rosacea patients with different skin subtypes (phymatous, erythematotelangiectatic and papulopustular) and ocular involvement and 30 healthy controls. Plasma native thiol (NT), total thiol (TT) and disulfide levels of the patients and controls were measured using an automated spectrophotometric method, and disulfide/native thiol ratio (DNTR), disulfide/total thiol ratio (DTTR) and native thiol/total thiol ratio (NTTR) were calculated. Tear breakup time (TBUT), meiboscore, Schirmer, ocular surface disease index (OSDI) and rosacea-specific quality of life scale (RosaQoL) were measured clinically. Results: Disulfide, DNTR and DTTR were significantly higher, and NT, TT and NTTR were significantly lower in the rosacea patients compared to the controls (p < 0.001). TBUT and Schirmer were significantly lower, and meiboscore and OSDI were significantly higher in the patients compared to the controls (p < 0.01). According to the skin subtypes, disulfide, DNTR and DTTR were significantly higher, and NTTR was significantly lower in the erythematotelangiectatic subtype compared to the other subtypes (p < 0.002). TBUT was significantly lower, and RosaQol was significantly higher in the erythematotelangiectatic subtype (p < 0.0083). Strong correlations were found between DNTR and TBUT and between DNTR and Meiboscore in all subtypes (p < 0.005), while there were strong correlations between DNTR and OSDI and between DNTR and RosaQol only in the erythematotelangiectatic and papulopustular subtypes (p < 0.05). Conclusions: The thiol/disulfide homeostasis shifted towards disulfides, an indicator of oxidative stress in rosacea, and this was more pronounced in the erythematotelangiectatic subtype. The impairment in TBUT and RosaQol was also more prominent in the erythematotelangiectatic subtype and strongly associated with the DNTR.

Prolidase activity in women with polycystic ovarian syndrome undergoing assisted conception.

Background: Prolidase is a manganese (Mn)-dependent cytosolic exopeptidase that degrades imidodipeptides with C-terminal proline or hydroxyproline. Prolidase recycling from imidodipeptides plays a critical role in collagen resynthesis and extracellular matrix (ECM) remodelling. Following an increase in gonadotropins, ovarian and follicular collagen undergo substantial degradation. Abnormal ovarian ECM composition is associated with polycystic ovary syndrome (PCOS). This study aimed to examine prolidase activity in the serum and follicular fluid (FF) of women undergoing in vitro fertilisation/intracytoplasmic sperm injection (IVF/ICSI) treatment, comparing those with PCOS to those with normal ovarian function.Methods: This prospective study enrolled 50 participants, of whom 44 were included. PCOS diagnosis followed the Rotterdam consensus criteria, with 20 patients constituting the study group. The control group comprised 24 individuals with mild-to-moderate male infertility. Prolidase enzyme activity in serum and FF was measured using the Chinard reagent via spectrophotometric analysis and compared between the groups.Results: Serum and FF prolidase levels were significantly lower in patients with PCOS (p < 0.05). A direct correlation was observed between serum and FF prolidase levels (p < 0.05). Although blastocyst quality scoring (BQS) significantly decreased in PCOS patients, no statistical difference was observed in the clinical pregnancy rate between the groups (p < 0.05) (p > 0.05). A negative correlation existed between serum prolidase levels and total antral follicle (AF) count (p < 0.05). Conversely, both serum and FF prolidase levels positively correlated with BQS (r = 0.574)(p < 0.05) (r = 0.650)(p < 0.05).Conclusions: Patients with PCOS showed lower serum and FF prolidase levels, indicating abnormal degradation of ovarian and follicular collagen, potentially causing anovulation.

Polycystic ovary syndrome (PCOS), the most prevalent endocrinopathy among reproductive-aged women, affects approximately 3­15% of this demographic. Long-term disorders such as cardiovascular disease, type 2 diabetes mellitus, obesity, and infertility are commonly associated with PCOS, with approximately 70% of affected women experiencing infertility. Although the aetiology of PCOS remains unclear, complex multigenic disorders and environmental factors such as abnormal ovarian extracellular matrix composition, disruption of the inflammatory pathway, and lifestyle factors have been found to be related.This study addresses the aetiology of PCOS, focusing on the close association between abnormal ovarian extracellular matrix composition and the syndrome, as seen in previous reports. Prolidase is a manganese-dependent cytosolic exopeptidase that degrades imidodipeptides using the C-terminal proline or hydroxyproline. Proline recycling from imidodipeptides by prolidase plays a critical role in the resynthesis of collagen and remodelling of the extracellular matrix. Our aim was to evaluate prolidase activity in the serum and follicular fluid of women diagnosed with PCOS. Our findings revealed a direct correlation between serum and follicular fluid prolidase levels, both of which were diminished in women with PCOS. Furthermore, a negative correlation was observed between serum prolidase levels and total antral follicle count indicating a potential link between prolidase activity and ovarian follicle development. In contrast, both serum and follicular fluid prolidase levels were positively correlated with blastocyst quality. In conclusion, PCOS patients showed lower serum and follicular fluid prolidase levels, indicating abnormal degradation of ovarian and follicular collagen, and potentially causing anovulation. Future studies measuring manganese levels in larger numbers of participants are required.

The Effect of Preoperative Carbohydrate-containing Fluid Consumption on Maternal Oxidative Stress Markers During Elective Cesarean Delivery.

PURPOSE: The purpose of this study was to evaluate the effect of carbohydrate loading prior to the cesarean surgery under spinal anesthesia on thiols and ischemia-modified albumin (IMA) levels. DESIGN: Prospective, randomized placebo-controlled study. METHODS: Seventy-nine pregnant women planned for cesarean sections under spinal anesthesia at Karaman Training and Research Hospital were randomized into a control group (group C) (n = 42), and an oral carbohydrate preloading group (group OCH) (n = 37). OCH loading requires consuming 400 mL the night before surgery and 200 mL up to 2 hours before anesthesia. Group OCH consumed an oral carbohydrate-rich beverage (Nutricia-Fantomalt), and group C consumed an equal volume of water. This study investigated thiol-disulfide homeostasis after preoperative carbohydrate consumption. Preoperative gastric fluid, volume, antral cross-sectional area, hypotension following the birth, and fetal blood gas parameters were compared across groups. FINDINGS: Thiols and IMA levels did not differ across groups before and after surgery (P > .05). Gastric ultrasonography showed similar antral cross-sectional area and stomach volume between groups (P = .172, P = .128, respectively). When surgery caused hypotension, group OCH received more ephedrine for surgery-induced hypotension, although this difference is not statistically significant (P = .704). A clustered error bar (95% confidence interval) plot with an interpolation line was used for a time-based comparison of mean differences in heart rate and mean arterial pressure between the groups. CONCLUSIONS: This study supports that mothers' thiols and IMA levels were unaffected by preoperative OCH loading before cesarean surgery. We did not examine thiol and its derivatives in umbilical cord blood; hence, we can not comment on thiol/disulfide homeostasis levels in neonates.

Heavy Metal and Thiol/Disulfide in Children with Attention-Deficit and Hyperactivity Disorder.

Background: In the etiology of attention-deficit and hyperactivity disorder (ADHD), oxidative stress and heavy metal exposure are still controversial topics. In this study, our goal was to examine heavy metal levels and oxidative balance in newly diagnosed patients with ADHD and reveal whether heavy metal levels have an effect on the oxidation balance. Methods: The study included 35 patients with newly diagnosed ADHD and 31 healthy control groups of similar age and gender. Participants' parents or caregivers completed a semi-structured questionnaire regarding their children's breastfeeding and prenatal and postnatal smoking exposures. The levels of heavy metals lead (Pb), mercury (Hg), and cadmium were measured with inductively coupled plasma optical emission spectroscopy, and a unique automated spectrophotometric approach was used to quantify serum total thiol, native thiol, and disulfide quantities and ratios. Results: The rate of smoking during pregnancy was significantly higher in the ADHD group than in the control group (P = .030). Compared to the control group, the native and total thiol levels of children with ADHD were significantly higher (P < .001). Likewise, the ADHD group had significantly higher Hg levels compared to the control group (P = .002). Cadmium levels were substantially greater in the control group compared to the ADHD group (P < .001). However, there was no significant difference between Pb levels in the ADHD and the control group (P = .844). Conclusion: Exposure to Hg and prenatal smoking may contribute to the development of ADHD in childhood. In response to oxidative stress, the young brains of children with ADHD may enhance their antioxidant levels.

The Role of the Lipid Profile and Oxidative Stress in Fatigue, Sleep Disorders and Cognitive Impairment in Patients with Multiple Sclerosis.

The aim of this study is to investigate the relationship of the lipid profile, dysfunctional high-density lipoprotein, ischaemia-modified albumin and thiol-disulfide homeostasis with cognitive impairment, fatigue and sleep disorders in patients with multiple sclerosis. The cognitive functions of patients were evaluated with the Brief International Cognitive Assessment for Multiple Sclerosis battery. Fatigue was evaluated with the Fatigue Severity Scale and the Fatigue Impact Scale. The Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale were used to assess patients' sleep disturbance. Peripheral blood samples were collected, and lipid levels and myeloperoxidase and paraoxonase activity were measured. The myeloperoxidase/paraoxonase ratio, which indicates dysfunctional high-density lipoprotein, was calculated. Thiol-disulfide homeostasis and ischaemia-modified albumin were measured.
We did not identify any relationship between dysfunctional high-density lipoprotein and the physical disability, cognitive decline, fatigue and sleep problems of multiple sclerosis. Thiol-disulfide homeostasis was associated with cognitive scores. The shift of the balance towards disulfide was accompanied by a decrease in cognitive scores. On the other hand, we did not detect any relationship between fatigue and sleep disorders and thiol-disulfide homeostasis. Our findings revealed a possible correlation between cognitive dysfunction and thiol-disulfide homeostasis in multiple sclerosis patients.

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.

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

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

Predictive effect of thiol/disulfide homeostasis dynamics on early pregnancy viability: A case-control study.

Objective: The main aim of this study was to investigate the differences in maternal serum thiol/disulfide homeostasis among women with abortion imminens (AI), missed abortion (MA), and healthy pregnancies during the first trimester. Materials and Methods: This was a prospective case-control study. This study was conducted on pregnant women who visited the Obstetrics Clinic at University of Health Sciences Turkey, Etlik Zübeyde Hanim Gynecology Training and Research Hospital and were diagnosed with either AI or MA during the 6th to 14th weeks of pregnancy. The participants had a normal pregnancy follow-up, no chronic illnesses, and did not take any multivitamin or antioxidant supplements except for folic acid. The study incorporated 33 pregnant women with AI, 36 with MA, and 40 with normal pregnancies. Age, and body mass index were matched across the three groups. This study used a recently developed automated spectrophotometric technique to quantify thiol/disulfide concentrations. Results: The AI group had considerably elevated levels of total thiol and native thiol (SH) compared with the MA group. Nevertheless, there was no notable disparity observed between the group of healthy pregnancies and the other two groups. Serum disulfide (SS) levels did not exhibit any significant variations among the three groups. Similarly, the ratios of SS/SH, SS/total thiol, and SH/total thiol did not show any significant differences between the groups (p>0.05). Conclusion: Patients with MA had decreased levels of total thiol and SH, which possess antioxidant capabilities, compared to the AI group. A decrease in antioxidant levels in the body may contribute to the etiology of MA. When considering our findings alongside existing literature, it remains inconclusive whether the serum thiol-disulfide ratio can predict a healthy pregnancy or MA following AI. Therefore, it is not yet seen as a promising diagnostic tool for assessing pregnancy viability. Additional investigation is required to establish the influence of dynamic thiol/disulfide homeostasis on early pregnancy loss.

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

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

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

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

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.