Evaluation of thiol disulfide balance in adolescents with vitamin B12 deficiency

Advances in pediatrics in 2023: choices in allergy, analgesia, cardiology, endocrinology, gastroenterology, genetics, global health, hematology, infectious diseases, neonatology, neurology, pulmonology

In the last year, there have been many remarkable articles published in the Italian Journal of Pediatrics. This review highlights papers that can be potentially helpful in healthcare practice among the most cited or accessed papers on the journal website. We have chosen key articles on allergy, analgesics, cardiology, endocrinology, gastroenterology, genetics, global health, infectious diseases, neonatology, neurology and pulmonology. Advances in understanding risk factors, mechanisms, diagnosis, treatment options and prevention of pediatric diseases have been discussed and in the context of the subsequent steps. We think that progresses achieved in 2023 will have a significant impact on the management of diseases in childhood.

Evaluation of vitamin B12 levels among severe obese and obese adolescents

Obesity, whose prevalence is increasing globally, is malnutrition that causes micro/macronutrients and vitamin deficiencies in adolescents. Vitamin B12 plays a prominent role in the body systems such as remethylation, deoxidation, and DNA synthesis. We aimed to examine the relationship between severe obese/obese adolescents and vitamin B12 levels in this study. This study was conducted as a case-control study consisting of 44 obese and 40 healthy control adolescents aged 11-17 years. Obesity was diagnosed using body mass index (BMI) charts defined by the World Health Organization according to age and gender. Vitamin B12 deficiency was found to be 34.1% in the patient obesity group, while it was 12.5% in the control group (p = 0.02). Homeostatic Model Assessment for Insulin Resistance levels were found to be 3.09 (1.9-5.29) higher in the severely obese group (p < 0.001). The median level of vitamin B12 in the obese group was 173 (122.5-220.7) in the severe obese group, 197 (146.5-302.7) in the obese group, and 252.5 (192.8-302) in the control group (p = 0.021). We found that obesity has a 1.6-fold decreasing effect on vitamin B12 levels. This study shows the clinician the importance of monitoring BMI and vitamin B12 levels in obese adolescents, given the effects of vitamin B12 on neuronal migration, metabolic reactions, and many systems in the body. Further researches are needed to investigate the pathophysiology and effect of low vitamin B12 levels in obese adolescents.

Thiol/disulfide homeostasis as a new oxidative stress marker in patients with Fabry disease

This is the first study to show both dynamic thiol-disulfide balance and oxidative stress levels in patients with Fabry disease (FD). This prospective study consists of 30 FD patients and 30 healthy controls. Thiol and disulfide values of the study groups were evaluated using a new, cost-effective and fully automatic colorimetric method. A total of 60 subjects were included in the study. A statistically significant difference was found between the patient and control groups for native and total thiol levels (p < 0.001). In addition, disulfide levels were significantly higher in FD patients compared with the control group (p < 0.003). Native thiol levels showed significantly negative correlation with lysosomal globotriaosylceramide, total oxidant status (TOS), and oxidative stress index (OSI) levels. In addition, a positive correlation was found between disulfide/natural thiol and disulfide/total thiol ratios and TOS, OSI, and blood urea nitrogen. We found total antioxidant status levels were lower in the patient group compared to the control group, while TOS and OSI levels were higher and were statistically significant. This study highlights for the first time a novel, cost-effective and fully automated measurement of thiol-disulfide levels in patients with FD. Determination of thiol levels can make important contributions to understand the etiopathogenesis and follow-up of the disease in FD patients.

Evaluation of Oxidative Stress Levels and Dynamic Thiol-disulfide Balance in Patients with Retinopathy of Prematurity

PURPOSE

The aim of this study is to evaluate both dynamic thiol-disulfide homeostasis and oxidative stress (OS) levels in patients with retinopathy of prematurity (ROP).

METHODS

A total of 129 infants of <34 weeks gestational age were enrolled in the present study. The thiol-disulfide homeostasis was determined by using the new, cost-effective and fully automated colorimetric method. Total antioxidant status (TAS), Total oxidant status (TOS) and Oxidative stress index (OSI) levels were evaluated.

RESULTS

We found serum TAS levels were lower while serum TOS and OSI levels were significantly higher in patients with ROP compare to the without ROP group (p < .05). However, native, total and disulfide values were not statistically significant between the groups (p > .05). In addition, we also evaluated the native, total and disulfide levels in patients with ROP according to grades and no statistically significant results were found (p > .05). Low birth weight (p = .001), gestational age (p = .001) and 5-min Apgar score were significantly lower in the ROP group.

CONCLUSION

This study revealed that dynamic thiol-disulfide homeostasis was changed in patients with ROP. Increased TOS and decreased TAS levels may be associated with functional reduction of the antioxidant system due to increased OS. This indicate that ROP patients are highly sensitive to OS. The dynamic thiol-disulfide homeostasis may conduce to the pathophysiological mechanism and disease follow-up in patients with ROP. The results of this study show that ROP patients are highly sensitive to oxidative stress.

Effect of mode of delivery on neonatal oxidative stress and dynamic thiol-disulfide homeostasis

OBJECTIVE

To evaluate the effect of the mode of delivery on neonatal oxidative stress and dynamic thiol-disulfide homeostasis.

METHODS

Sixty women who were followed up in the Obstetrics and Gynecology clinic were included in this prospective study. Cord blood samples were obtained from women who underwent cesarean section (CS) and vaginal delivery (VD). Total oxidant status and total antioxidant status levels were measured by spectrophotometry. The dynamic thiol-disulfide balance was determined by colorimetry.

RESULTS

The total antioxidant status and oxidative stress index levels were higher and total oxidant status levels were lower in the VD group compared with the CS group. Native and total thiol levels were higher while disulfide levels were lower in the VD compared with the CS delivery group, while disulfide levels were higher in the CS group.

CONCLUSION

These results indicate that disulfide formation leads to decreased antioxidant capacity in women undergoing CS. Monitoring of dynamic thiol-disulfide levels may thus provide clinicians with important information on the oxidative stress status in newborns.

Vitamin B12-Multifaceted In Vivo Functions and In Vitro Applications

Vitamin B12 plays a key role in DNA stability. Research indicates that vitamin B12 deficiency leads to indirect DNA damage, and vitamin B12 supplementation may reverse this effect. Vitamin B12 acts as a cofactor for enzymes such as methionine synthase and methylmalonyl-CoA mutase, which are involved in DNA methylation and nucleotide synthesis. These processes are essential for DNA replication and transcription, and any impairment can result in genetic instability. In addition, vitamin B12 has antioxidant properties that help protect DNA from damage caused by reactive oxygen species. This protection is achieved by scavenging free radicals and reducing oxidative stress. In addition to their protective functions, cobalamins can also generate DNA-damaging radicals in vitro that can be useful in scientific research. Research is also being conducted on the use of vitamin B12 in medicine as vectors for xenobiotics. In summary, vitamin B12 is an essential micronutrient that plays a vital role in DNA stability. It acts as a cofactor for enzymes involved in the synthesis of nucleotides, has antioxidant properties and has potential value as a generator of DNA-damaging radicals and drug transporters.

Association between thiol-disulfide hemostasis and transient tachypnea of the newborn in late-preterm and term infants

BACKGROUND

Transient tachypnea of the newborn (TTN), which is the most common respiratory disease in the neonatal period, increases respiratory workload in newborns. We purposed to evaluate the oxidative stress (OS) status and thiol disulfide hemostasis in late preterm and term newborns with TTN in this study.

METHODS

The study was carried out in a single-centre neonatal intensive care unit to investigate the effect of continuous airway positive pressure (CPAP) on the oxidative system in newborns with TTN. Thiol (native and total) and disulfide levels, total antioxidant and oxidant status (TAS/TOS) and Oxidative stress index (OSI) levels were measured.

RESULTS

Total thiol levels measured before treatment was 429.5 (369.5-487) µmol/L in the late preterm group and 425 (370-475) µmol/L in the term group (p = 0.741). We found significant changes in TOS, OSI and TAS levels after CPAP treatment in the late preterm group (p < 0.001, p < 0.001, p = 0.012 respectively). It was also found that the disulfide level, which was 26.2 (19.2-31.7) before the treatment, decreased to 19.5 (15.5-28.75) after the treatment (p = 0.001) in late preterms.

CONCLUSION

CPAP treatment reduced the OS status burden associated with TTN in neonates. The late preterm newborns with TTN are more affected by OS and increased OS levels decrease with CPAP treatment.