Assessment of thiol/disulfide balance as an oxidative stress marker in children with β-thalassemia major

The association of pro-oxidant/antioxidant balance and blood parameters in patients with beta-thalassemia major: a cross-sectional study

Background

Oxidative stress due to iron accumulation in patients with beta-thalassemia major (BTM) causes complications such as tissue damage and destruction. This study aimed to assess the association between the serum prooxidant/antioxidant balance (PAB) and blood parameters in patients with BTM.

Methods

This cross-sectional study included 92 patients with BTM. In this study, PAB was measured using an enzyme-linked immunosorbent assay (ELISA). Serum ferritin, blood urea nitrogen (BUN), creatinine (Cr), alanine aminotransferase (ALT), aspartate aminotransferase (AST), thyroid-stimulating hormone (TSH), total cholesterol (TC), triglyceride (TG), complete blood cell count (CBC), and history of blood transfusion were recorded. The association of the blood parameters was assessed across the tertiles (T) of serum PAB (highest T vs. lowest T).

Results

The results showed that high serum ferritin was directly associated with serum PAB [odds ratio (OR), 12.80; 95% confidence interval (CI), 2.98‒54.91; T3 vs. T1]. Also, direct associations were found for high TC (OR, 4.97; 95% CI, 1.42‒17.32; T3 vs. T1), high ALT (OR, 4.95; 95% CI, 1.33‒18.46; T3 vs. T1) and high TSH (OR, 3.78; 95% CI, 1.10‒13.02; T3 vs. T1).

Conclusion

The findings of the present study showed that serum PAB levels were directly associated with ferritin, ALT, TC, and TSH levels. This indicates that improvements in blood parameters, especially ferritin and TSH levels, occur by ameliorating oxidative stress in patients with BTM.

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

BACKGROUND

The aim of this study is to develop new perspectives to prevent or reduce potential organ damage due to iron-mediated oxidation in thalassemia major patients.

METHODS

Seventy patients were included in this study. Blood samples were taken from the patients before and after transfusion. Total thiol, native thiol, disulfide, disulfide/native thiol percentage ratio, ischemia modified albumin (IMA), total antioxidant status (TAS), total oxidant status (TOS), and ferroxidase levels were determined. Additionally, undepleted thiol level (UTL) was determined as a new parameter associated with organ damage.

RESULTS

After transfusion, the levels of native thiol, total thiol, disulfide, TAS, ferroxidase, and TOS were higher, while the IMA levels and disulfide/native thiol percent ratio were lower. Significant correlations were found between antioxidant and oxidant tests before and after transfusion. Additionally, a negative correlation was found between the TOS and UTL levels of the patients measured before the transfusion.

CONCLUSION

In the present study, transfusion therapy increased both oxidation and the antioxidant levels. In addition, the term UTL has been introduced as a parameter that enables the determination of the oxidation level that may cause potential organ damage in transfusion-dependent thalassemia patients.

Dynamic Thiol-Disulfide Homeostasis in Children With β-Thalassemia Trait

In children with β-thalassemia (β-thal) trait, tissue damage occurs with oxidative stress due to oxygen free radicals and reactive oxygen species (ROS) production. Dynamic thiol-disulfide homeostasis (DTDH) is one of the most important indicators showing the pro-oxidant/antioxidant status in the body. In this study, we aimed to examine the status of DTDH by measuring native thiol, disulfide, and total thiol levels in children with β-thal trait. The study included 40 children with β-thal trait and 30 healthy controls (matched by age and gender). The DTDH parameters were measured by an automated method and results were compared between the groups. The levels of native thiol, total thiol, and disulfide in children with β-thal trait group were statistically significantly higher than the control group (p < 0.001). There was no significant difference in disulfide/native thiol, disulfide/total thiol, and native thiol/total thiol levels between the groups. In addition, there was no correlation between hemoglobin (Hb) and serum ferritin levels with the markers of DTDH in children with β-thal trait. In our study, a significant increase was found in native thiol, total thiol, and disulfide levels in response to oxidative stress in children with β-thal trait compared to the healthy control group. Disulfide levels of the children with β-thal trait were higher than the control group, showing oxidative stress is high in β-thal trait. Accordingly, it increases the native thiol and total thiol capacity as compensation.

Effect of tannic acid-templated mesoporous silica nanoparticles on iron-induced oxidative stress and liver toxicity in rats

The present study sought to investigate the effects of amino-functionalized tannic acid-templated mesoporous silica nanoparticles (TA-MS-NH₂ NPs) on giving rats protection against iron-induced liver toxicity. To this end, the TA-MS-NH₂ NPs were characterized using field-emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier-transform infrared spectroscopy (FTIR). Moreover, 50 Wistar rats were randomly divided into one control group (group 1) and four experimental groups (groups 2- 5) (n = 10), each of which received 100 mg/kg oral normal saline and FeSO₄, respectively. Then, post-exposure hepatotoxicity and oxidative stress markers were measured in two intervals, i.e., after 4 and 24 h, followed by the measurement of the acute iron toxicity. Furthermore, hepatotoxicity markers, including the alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and total antioxidant capacity (TAC), were measured via Ferric Reducing Antioxidant Power (FRAP) and 2,2,1-diphenyl-1-picrylhydrazyl (DPPH) assays. Also, malondialdehyde (MDA), total thiol groups, advanced oxidation protein products (AOPP), and nitrite/nitrate (NOx) levels were measured as oxidative stress markers in the serum samples. The results indicated that oral administration of iron significantly elevated the liver enzymes and altered the level of oxidative stress markers. It was also found that treatment with TA-MS-NH₂ NPs meaningfully protected against hepatotoxicity, decreased ALT, AST, ALP, and significantly improved oxidative stress markers by decreasing MDA, AOPP, and NOx levels and increasing TAC and thiol group contents, proving that TA-MS-NH₂ NPs could protect rats against iron-induced acute liver toxicity through their antioxidant features.

Impaired thiol/disulphide homoeostasis in children with steroid-sensitive nephrotic syndrome

BACKGROUND

Abnormal thiol/disulphide homoeostasis (TDH) is responsible for the pathogenesis of various diseases. We aimed to examine the TDH in children with steroid-sensitive nephrotic syndrome (SSNS).

METHODS

A total of 131 children, 60 with SSNS and 71 healthy controls, participated in the study. Plasma total thiol (TT), native thiol (SH) and disulphide (SS) levels in the SSNS during remission and control groups were estimated using a new method developed by Erel and Neselioglu.

RESULTS

Albumin, TT, SH levels and SH/TT ratio were decreased, whereas SS/SH and SS/TT ratios were elevated in SSNS group compared with control group. However, there was no significant difference in SS levels between the two groups. Albumin level was positively correlated with TT, SH and SS levels in the SSNS group.

CONCLUSIONS

We found that TDH shifts in favour of oxidants in children with SSNS in remission. This shift indicates that SSNS patients are exposed to augmented oxidative stress.