The effect of low dose ionizing radiation exposure on dynamic thiol-disulfide homeostasis and ischemia modified albumin levels: an observational study / Efeito da exposição à radiação ionizante de baixa dose na homeostase dinâmica de tiol-dissulfeto e níveis de albumina modificada por isquemia: estudo observacional

Abstract Background: The primary objective of this study was to investigate the effect of low dose ionizing radiation exposure on thiol/disulfide homeostasis and ischemia modified albumin levels. The secondary objective is to compare thiol/disulfide homeostasis and ischemia modified albumin levels among the personnel exposed to low dose ionizing radiation in anesthesia application areas, in and out of the operation room. Methods: The study included a total of 90 volunteers aged between 18 and 65 years old, with 45 personnel working in a setting with potential for radiation exposure (Exposed Group) and 45 personnel in a setting without radiation exposure (Control Group). Their native thiol, total thiol, disulphide, albumine and IMA levels were measured. Exposed group included personnel who were exposed to radiation outside the operating room - Operation room (−) Group and inside the operating room - Operation room (+) Group. Results: Albumin, native and total thiol levels were significantly lower in the participants exposed to radiation in the anesthesia application area; no statistically significant difference was found in terms of disulfide and ischemia modified albumin levels. In the Operation room (−) Group exposed to radiation, native thiol and total thiol values were significantly lower compared to the Operation room (+) Group. Conclusion: Awareness of being in danger of oxidative stress should be established in personnel exposed to radiation in the anesthesia application area following low dose ionizing radiation exposure, and the necessary measures should be taken.

Resumo Justificativa: O objetivo principal do estudo foi investigar o efeito de exposição à radiação ionizante de baixa dose nos níveis de homeostase tiol/dissulfeto e de albumina modificada por isquemia. O objetivo secundário foi comparar os níveis de homeostase tiol/dissulfeto e albumina modificada por isquemia entre indivíduos expostos à radiação ionizante de baixa dose nas áreas de procedimentos anestésicos, dentro e fora da sala de cirurgia. Método: O estudo incluiu um total de 90 voluntários com idades entre 18 e 65 anos, 45 profissionais que trabalhavam em ambiente de exposição potencial a radiação (Grupo Exposto) e 45 profissionais que trabalhavam em ambiente sem exposição à radiação (Grupo Controle). Foram medidos os níveis de tiol nativo, tiol total, dissulfeto, albumina e albumina modificada por isquemia. O Grupo Exposto era constituído por profissionais expostos a radiação fora da sala de cirurgia - Grupo sala de cirurgia (-) e na sala de cirurgia - Grupo sala de cirurgia (+). Resultados: Os níveis de albumina, tiol nativo e total foram significantemente mais baixos nos participantes expostos à radiação em área de realização de anestesia, e nenhuma diferença estatisticamente significante foi encontrada para os níveis de dissulfeto e albumina modificada por isquemia. No Grupo exposto sala de cirurgia (-), os valores de tiol nativo e tiol total foram significantemente mais baixos quando comparados ao Grupo sala de cirurgia (+). Conclusões: Os profissionais expostos à radiação em área de realização de anestesia devem ser conscientizados quanto ao perigo do estresse oxidativo após exposição à radiação ionizante de baixa dose e medidas cabíveis devem ser instituídas.

The effect of continuous ventilation on thiol-disulphide homeostasis and albumin-adjusted ischemia-modified albumin during cardiopulmonary bypass

Abstract Objective: To investigate the effect of continuous lung ventilation with low tidal volume on oxidation parameters, such as thiol/disulphide homeostasis and albumin-adjusted ischemia-modified albumin (AAIMA), during cardiopulmonary bypass (CBP) in coronary artery bypass grafting (CABG). Methods: Seventy-four patients who underwent elective CABG with CPB were included in the study. Blood samples were taken in the preoperative period, 10 minutes after CPB, and six and 24 hours postoperatively. Patients were assigned to the continuous ventilation group (Group 1, n=37) and the non-ventilated group (Group 2, n=37). The clinical characteristics, thiol/disulphide homeostasis, ischemia-modified albumin (IMA), and AAIMA levels of the patients were compared. Results: A significant difference was found between the groups regarding native thiol, total thiol, and IMA levels at the postoperative 24th hour (P=0.030, P=0.031, and P=0.004, respectively). There was no difference between the groups in terms of AAIMA. AAIMA levels returned to preoperative levels in Groups 1 and 2, at the 6th and 24th postoperative hours, respectively. Length of hospital stay was significantly shorter in Group 1 (P<0.001) than in Group 2. Conclusion: Continuous ventilation during CPB caused an increase in native and total thiol levels, an earlier return of AAIMA levels, and shorter hospital stay. Continuous ventilation may reduce the negative effects of CPB on myocardium (Table 2, Figure 1, and Reference 31).

Role of native thiol, total thiol and dynamic Disulphide in diagnosis of patient with prostate cancer and prostatitis

ABSTRACT Background: Our study investigates whether Native Thiol, Total Thiol and disulphide levels measured in serum of patients with prostate cancer and prostatitis and of healthy subjects, have any role in differential diagnosis. Materials and Methods: Patients followed up for histopathologically verified diagnosis of prostate cancer and prostatitis in 2016-2017 at the Medicalpark Gaziantep Hospital Urology Clinic were included in the study. Native Thiol (NT), Total Thiol (TT), Dynamic Disulphide (DD) levels in serum were measured by a novel automated method. Results: NT, TT, DD, NT / TT ratios, DD / TT ratio and DD / NT ratio were measured as 118.4 ± 36.8μmoL / L, 150.3 ± 45.3μmoL / L, 15.9 ± 7μmoL / L, 78.8 ± 7μmoL / L, 10.5 ± 3.5μmoL / L, 13.8 ± 5.8μmoL / L respectively in patients with prostate cancer; as 116.4 ± 40.5μmoL / L, 147.5 ± 50.1μmoL / L, 15.5 ± 8.7μmoL / L, 79.7 ± 9μmoL / L, 10.1 ± 4.5μmoL / L, 13.5 ± 7.2μmoL / L in patients with prostatitis and as 144.1 ± 21.2μmoL / L, 191 ± 32.3μmoL / L, 23.4 ± 10.1μmoL / L, 76.1 ± 98.3μmoL / L, 11.9 ± 4.1μmoL / L, 16.4 ± 6.9μmoL / L in healthy subjects. Significant difference was detected between groups of NT, TT and DD levels (p = 0.008, p = 0.001, p = 0.002). No significant difference was detected in terms of the NT / TT, DD / TT and DD / NT rates (p = 0.222, p = 0.222, p = 0.222). Conclusions: Serum NT, TT, DD levels in patients with prostatitis and prostate cancer were found significantly lower compared to the control group. This indicates that just as inflammation, prostate cancer also increases oxidative stress on tissues.

Dynamic thiol/disulfide homeostasis in patients with age-related macular degeneration / Homeostase dinâmica de tiol/dissulfureto em pacientes com degeneração macular relacionada à idade

ABSTRACT Purpose: We evaluated dynamic thiol/disulfide homeostasis (TDH), malondialdehyde (MDA) levels, and catalase (CAT) activity in patients with age-related macular degeneration (AMD). All analyzes were conducted on plasma samples. Methods: Thirty-two patients with AMD and 38 age-matched healthy controls were included. Native thiol, total thiol, and disulfide levels and TDH status were determined using a novel, automated assay. MDA levels and CAT activity were determined. Percentages were compared using the chi-squared test. The Student's t-test and Mann-Whitney U-test were used to compare quantitative variables. Results: Native thiol levels were significantly lower (p=0.004) in patients with AMD (272.02 ± 52.41 µmol/l) than in healthy individuals (307.82 ± 47.18 µmol/l), whereas disulfide levels were significantly higher (p<0.001) in patients with AMD than in controls (21.64 ± 5.59 vs. 14.48 ± 5.37 µmol/L). Dynamic TDH was also significantly lower (p<0.001) in patients with AMD than in controls (13.41 ± 4.3 vs. 25.41 ± 14.52 µmol/l). No significant differences were evident in total thiol or MDA levels. Mean CAT activity was significantly higher (p=0.043) in patients with AMD compared with controls (0.035 vs. 0.018 k/ml). Conclusions: The antioxidant/oxidant balance demonstrated by dynamic TDH is shifted to the oxidative side in patients with AMD.

RESUMO Objetivo: Avaliar a homeostase dinâmica de tiol/dissulfureto e os níveis de malon dialdeído (MDA) e catalase (CAT) em pacientes com degeneração macular relacionada à idade (DMRI). Todas as análises foram realizadas em amostras de plasma. Métodos: Foram incluídos 32 pacientes com degeneração macular relacionada à idade e 38 controles saudáveis de idade similar. Os níveis de tiol, tiol total, dissulfureto e estado de homeostase de tiol/dissulfureto foram determinados utilizando um novo ensaio automatizado. Os níveis de atividade de MDA e CAT foram também determinados. As porcentagens foram comparadas pelo teste do qui-quadrado. O teste t de Student e o teste U de Mann Whitney foram utilizados para comparar variáveis quantitativas. Resultados: Os níveis de tiol nativo foram significativamente menores (p=0,004) nos pacientes com degeneração macular relacionada à idade (272,02 ± 52,41 µmol/l) do que nos indivíduos saudáveis (307,82 ± 47,18 µmol/l), enquan to os dissulfetos foram significativamente maiores em pacientes com degeneração macular relacionada à idade (21,64 ± 5,59 µmol/l versus 14,48 ± 5,37 µmol/l, respectivamente, p<0,001). A homeostase dinâmica de tiol/dissulfureto também foi significativamente menor nos pacientes com degeneração macular re la cionada à idade (13,41 ± 4,3 µmol/l) versus os controles (versus 25,41 ± 14,52 µmol/l, p<0,001). Não foram observadas diferenças significativas nos níveis de tiol total ou MDA. A atividade média de CAT foi significativamente mais elevada (p=0,043) em doentes com degeneração macular relacionada à idade (0,035 k/ml vs. 0,018 k/ml). Conclusões: O equilíbrio antioxidante/oxidante demonstrado pela homeostase dinâmica de tiol/dissulfeto é deslocado para o lado oxidativo em pacientes com de generação macular relacionada à idade.

Relationship of Oxidative Stress in Hepatitis B Infection Activity with HBV DNA and Fibrosis

BACKGROUND: The aim of this study was to evaluate oxidative stress in various clinical forms of hepatitis B infection and to investigate its role in the development of the chronic form of the disease. METHODS: Ninety-three patients with inactive hepatitis B surface antigen (HbsAg) carrier state (IHBCS), 65 patients with chronic hepatitis B infection (CHB), and 42 healthy adults were included in the study. The following values were measured and compared in patient groups: total antioxidant status (TAS), total oxidative stress (TOS), oxidative stress index (OSI), sulfhydryl (SH), lipid peroxidation (LOOH), catalase (CAT), and ceruloplasmin. In patients with chronic hepatitis B, these values were compared with HBV DNA and fibrosis levels. RESULTS: ALT, TOS, LOOH, and OSI levels were higher in the CHB group compared to the other groups (P0.05). CONCLUSIONS: These finding suggested that oxidative stress is associated with hepatitis B activity.

Comparing the oxidative stress indexes of CVA patients with control group

In the recent years, oxidative stress was attended as one of the causal factors of ischemic stroke. In terms of the role of genetic, geographic and ethnic factors in the prevalence of stroke, This study was designed to compare the oxidative stress indexes of stroke patients with normal healthy subjects in this geographic area. In this case-control study, 36 patients older than 50 years with ischemic stroke and 45 healthy subjects with same age and sex, were enrolled. Five milliliter blood were drawn from all subjects. Samples were centrifuged and plasma was separated. Total antioxidant capacity, lipid peroxidation and thiol levels were measured respettively by FRAP, TEA and HU methods. Then the result was analyzed using t-test. Results showed total antioxidant capacity and thiol plasma levels were lower in stroke patients in compare to healthy subjects, but only the thiol group had significant difference [P = 0/001]. Although lipid peroxidation showed a slight but non-significant difference in stroke patients in compare to control group. These findings suggest oxidative stress in patients with acute ischemic stroke may be conseaqence of an imbalance in oxidant/antioxidant homeostasis. Therefore it may be useful to recommend antioxidant medications or diet for these patients

Antioxidant response to oxidative stress induced by smoking.

Oxygen free radicals have been hypothesized to play a pivotal role in the deleterious effects of smoking on health. The present study was undertaken to examine the oxidant and antioxidant system among smokers and nonsmokers. Fourteen smokers and 11 nonsmokers were enrolled for this study. The protein carbonyl levels in smokers were found to be significantly higher than in nonsmokers. The levels of plasma ascorbic acid, free sulfhydryl group, and erythrocyte reduced glutathione were lower in smokers compared to nonsmokers. In smokers the erythrocyte activities of both glutathione peroxidase and catalase were decreased when compared to that in nonsmokers. The data from the study reemphasizes the presence of oxidative stress in smokers. The concomitant decrease in the activities of both catalase and glutathione peroxidase found in the erythrocytes of smokers raises rational grounds for expressing concern over the increased susceptibility towards oxidative stress in these subjects.

Serum copper, ceruloplasmin, protein thiols and thiobarbituric acid reactive substance status in liver cancer associated with elevated levels of alpha-fetoprotein.

Serum copper, ceruloplasmin, protein thiols and thiobarbituric acid reactive substances (TEARS) were estimated in 25 patients of liver cancer. The copper to ceruloplasmin ratio was moderately increased (P<0.05) but the copper (P<0.001) and ceruloplasmin (P<0.001) levels were significantly increased in liver cancer patients when compared to controls. Protein thiols levels were found to be highly significant (P<0.001). Where as the TEARS levels were not found to be significant. Trace elements and free radicals have been implicated in the etiology of cancer. Hence the estimation of ceruloplasmin and protein thiols along with the copper may be of high value in the early diagnosis of cancer.

Ischemic preconditioning reduces peripheral oxidative damage associated with brain ischemia in rats

Brain ischemia followed by reperfusion causes neuronal death related to oxidative damage. Furthermore, it has been reported that subjects suffering from ischemic cerebrovascular disorders exhibit changes in circulating platelet aggregation, a characteristic that might be important for their clinical outcome. In the present investigation we studied tert-butyl hydroperoxide-initiated plasma chemiluminescence and thiol content as measures of peripheral oxidative damage in naive and preconditioned rats submitted to forebrain ischemia produced by the 4-vessel occlusion method. Rats were submitted to 2 or 10 min of global transient forebrain ischemia followed by 60 min or 1, 2, 5, 10 or 30 days of reperfusion. Preconditioned rats were submitted to a 10-min ischemic episode 1 day after a 2-min ischemic event (2 + 10 min), followed by 60 min or 1 or 2 days of reperfusion. It has been demonstrated that such preconditioning protects against neuronal death in rats and gerbils submitted to a lethal (10 min) ischemic episode. The results show that both 2 and 10 min of ischemia cause an increase of plasma chemiluminescence when compared to control and sham rats. In the 2-min ischemic group, the effect was not present after reperfusion. In the 10-min ischemic group, the increase was present up to 1 day after recirculation and values returned to control levels after 2 days. However, rats preconditioned to ischemia (2 + 10 min) and reperfusion showed no differences in plasma chemiluminescence when compared to controls. We also analyzed plasma thiol content since it has been described that sulfhydryl (SH) groups significantly contribute to the antioxidant capacity of plasma. There was a significant decrease of plasma thiol content after 2, 10 and 2 + 10 min of ischemia followed by reperfusion when compared to controls. We conclude that ischemia may cause, along with brain oxidative damage and cell death, a peripheral oxidative damage that is reduced by the preconditioning phenomenon

Effect of training on lipid peroxidation, thiol status and antioxidant enzymes in tissues of rats.

The effect of training on lipid peroxidation, thiol-status and certain antioxidant enzymes of glutathione system was studied in blood and tissues such as liver and skeletal muscle of rats. Exercise training was given by subjecting the rats to treadmill running. Training for a period of 6 weeks resulted in increased lipid peroxidation (P < 0.001) as indicated by thiobarbituric acid test and conjugated diene measurement in liver and muscle. Thiol levels (total and non-protein) were reduced. However, glutathione level in blood was increased and blood lipid peroxides were unaltered as a result of training compared to sedentary controls. Adaptive increases in three antioxidant enzyme activities were observed. The study indicates that training induces adaptation in the glutathione system.

Preventive action of zinc against lead toxicity.

The study was aimed to assess the protective efficacy of zinc against hemo and hematotoxicity induced by lead. Two groups of 8 rats each, were administered lead acetate 20 mg/kg bw (ip) for 3 days. One group in addition was injected 5 mg/kg bw (ip) zinc acetate for next three days. A third group of 8 rats was given three injections of normal saline and served as control. All the animals were sacrificed on eighth day and assessed for hematological changes, heme synthesizing pathway enzymes, hepatic drug metabolizing status and sulfhydryl levels in blood and liver. Lead administration resulted in decreased hemoglobin, increased reticulocytosis, depression of delta aminolevulinic acid dehydratase (ALAD) and uroporphyrinogen I synthetase (UPS) activity in blood and liver. In vitro metabolism of drugs aminopyrine, aniline and p-nitroanisole by liver homogenate and in vivo metabolism of pentabarbitone was also reduced in lead exposed rate. Zinc treated rats showed improved hematological profile and activated ALAD and UPS activity, recovery of N-demethylation of aminopyrine and O-demethylation of p-nitroanisole and partial restoration of free thiol levels in blood and liver thereby indicating that zinc could confer protection against lead toxicity.