Evaluation of dynamic thiol/disulfide redox state in community-acquired pneumonia

Oxidant and antioxidant balance in patients with COVID-19

BACKGROUND

A crucial balance exists between oxidant and antioxidant mechanisms in the functional immune system. We aimed to evaluate the contributions of balance between these systems to coronavirus disease 2019 (COVID-19), a devastating pandemic caused by viral infection.

METHOD

We analyzed serum oxidant and antioxidant stress parameters according to the clinical and demographic characteristics of children and adults with COVID-19 and compared them against the values of healthy controls. Serum native thiol (NT), total thiol (TT), disulfide, total antioxidant status, total oxidant status, and ischemia-modified albumin levels were evaluated and compared between groups.

RESULTS

A total of 79 children and 74 adults were evaluated in the present study, including 46 children and 40 adults with COVID-19, 33 healthy children, and 34 healthy adults. TT, NT, and disulfide levels were significantly lower in the adult COVID-19 group than in all other groups (p = .001, p = .001, and p = .005, respectively). Additionally, TT and NT levels were significantly lower in both pediatric and adult COVID-19 cases with severe disease course than mild/moderate course. TT and NT levels were identified as predictors for the diagnosis of the adult COVID-19 cases and as independent predictors for disease severity in both children and adults with COVID-19.

CONCLUSION

Parameters that reveal the oxidant and antioxidant capacity, including TT and NT, appear to be good candidates for the accurate prediction of the clinical course among patients with COVID-19.

Oxidant and Antioxidant Balance in Children with Community-Acquired Pneumonia

Objective The balance between oxidant and antioxidant defense mechanisms is crucial. In this article, we aimed to evaluate the role of this balance in community-acquired pneumonia (CAP) in children.

Methods We analyzed serum oxidant and antioxidant stress parameters according to the clinical and demographic data of children with CAP and compared them with healthy controls. Serum total antioxidant status (TAS) and total oxidant status (TOS) were evaluated and compared between the groups, along with levels of ischemia-modified albumin (IMA), antioxidant enzymes, nonenzymatic antioxidant factors, and plasma thiol.

Results Of 160 children evaluated, 106 had CAP (54 outpatients and 52 inpatients), and the other 54 were healthy (control group). Total thiol and native thiol levels were significantly lower in the inpatient group compared with the outpatient group (p = 0.004 and p = 0.005, respectively). Serum IMA differed significantly among the groups (p = 0.001), with inpatients showing the highest level. A positive correlation was found between serum IMA and C-reactive protein levels in patients with pneumonia (r = 0.351; p = 0.001).

Conclusion Parameters that provide information about antioxidant capacity may be useful in the diagnosis and prognosis of pneumonia. Our results suggest that plasma thiol levels and IMA may be good candidate biomarkers to predict hospitalization for CAP in children.

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.

Dynamic thiol/disulphide homeostasis and pathogenesis of Kawasaki disease

BACKGROUND

Kawasaki disease (KD) is an acute, self-limited, systemic vasculitis of unknown etiology. In the present study, we investigated whether there is a relationship between KD and dynamic thiol/disulphide homeostasis.

METHODS

This case-control study involved KD patients and healthy controls. Plasma total, native and disulphide thiol and the disulphide/native, disulphide/total and native thiol/total thiol ratios of all patients and the control group were analyzed simultaneously.

RESULTS

A total of 20 patients with KD (male/female, 12/8) and 25 age- and gender-matched healthy controls (male/female, 12/13) were evaluated. Native, total thiol and native thiol/total thiol ratio were significantly lower in KD patients than in the control group (P < 0.001). In contrast, disulphide thiol, disulphide/native thiol and disulphide/total thiol ratios were significantly higher in KD patients than control subjects (P < 0.001). In KD patients with coronary artery lesion (CAL), the native thiol and total thiol were significantly lower than in KD patients without CAL. In KD patients with CAL, the ratios of disulphide/total thiol and disulphide/native thiol were significantly higher than in those without CAL (P = 0.02 and P = 0.02, respectively), whereas the ratio of native/total thiol was significantly lower (P = 0.02).

CONCLUSION

The KD patients had lower plasma thiol (native and total) and higher disulphide thiol than controls, indicating that dynamic thiol/disulphide homeostasis might be an important indicator of inflammation in KD. Alteration and shifting of thiol/disulphide homeostasis to the oxidized side are correlated with the pathogenesis of KD and CAL.

Dynamic thiol/disulfide homeostasis in children with community-acquired pneumonia

BACKGROUND

Alteration in thiol level under oxidative stress may contribute to community-acquired pneumonia (CAP). The goal of this study was to determine whether there are changes in thiol/disulfide homeostasis and nitric oxide (NO) in children with CAP.

METHODS

In total, 130 participants were involved in the study. Of these, 65 had been diagnosed with CAP on admission, and the remaining 65 were healthy individuals. Serum total thiol and native thiol were measured in each participant using a novel automated spectrophotometric method. The amount of dynamic disulfide bonds and related ratios were calculated from these values. Serum NO was measured on chemiluminescence assay.

RESULTS

Average native thiol, total thiol, and disulfide in the CAP group were significantly lower than in the healthy individuals (P < 0.0001, P < 0.0001, P = 0.0126, respectively). In addition, disulfide/native thiol (P = 0.0002), and disulfide/total thiol ratios (P = 0.0004) were significantly higher, whereas the native thiol/total thiol ratio (P = 0.0004) was lower in the CAP group. High serum NO was noted in the CAP group (P = 0.0003), but there was no marked correlation between thiol/disulfide and NO.

CONCLUSION

The changes in endogenous thiol levels under oxidative stress may be associated with the pathogenesis of CAP in pediatric patients.