Response of antioxidant enzymes to intermittent and continuous hyperbaric oxygen

1990 ◽  
Vol 69 (1) ◽  
pp. 328-335 ◽  
Author(s):  
A. L. Harabin ◽  
J. C. Braisted ◽  
E. T. Flynn

Rats and guinea pigs were exposed to O2 at 2.8 ATA (HBO) delivered either continuously or intermittently (repeated cycles of 10 min of 100% O2 followed by 2.5 min of air). The O2 time required to produce convulsions and death was increased significantly in both species by intermittency. To determine whether changes in brain and lung superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSHPx) correlated with the observed tolerance, enzyme activities were measured after short or long HBO exposures. For each exposure duration, one group received continuous and one intermittent HBO; O2 times were matched. HBO had marked effects on these enzymes: lung SOD increased (guinea pigs 47%, rats 88%) and CAT and GSHPx activities decreased (33%) in brain and lung. No differences were seen in lung GSHPx or brain CAT in rats or brain SOD in either species. In guinea pigs, but less so in rats, the observed changes in activity were usually modulated by intermittency. Increases in hematocrit, organ protein, and lung DNA, which may also reflect ongoing oxidative damage, were also slowed with intermittency in guinea pigs. Intermittency benefited both species by postponing gross symptoms of toxicity, but its modulation of changes in enzyme activities and other biochemical variables was more pronounced in guinea pigs than in rats, suggesting that there are additional mechanisms for tolerance.

Zygote ◽  
2019 ◽  
Vol 27 (6) ◽  
pp. 432-435
Author(s):  
Thais Rose dos Santos Hamilton ◽  
Gabriela Esteves Duarte ◽  
José Antonio Visintin ◽  
Mayra Elena Ortiz D’Ávila Assumpção

SummaryLong-term heat stress (HS) induced by testicular insulation generates oxidative stress (OS) on the testicular environment; consequently activating antioxidant enzymes such as superoxide dismutase (SOD), glutathione reductase (GR) and glutathione peroxidase (GPx). The aim of this work was to immunolocalize antioxidant enzymes present in different cells within the seminiferous tubule when rams were submitted to HS. Rams were divided into control (n = 6) and treated group (n = 6), comprising rams subjected to testicular insulation for 240 h. After the testicular insulation period, rams were subjected to orchiectomy. Testicular fragments were submitted to immunohistochemistry for staining against SOD, GR and GPx enzymes. We observed immunolocalization of GPx in more cell types of the testis after HS and when compared with other enzymes. In conclusion, GPx is the main antioxidant enzyme identified in testicular cells in an attempt to maintain oxidative balance when HS occurs.


2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Israel Pérez-Torres ◽  
Verónica Guarner-Lans ◽  
Alejandra Zúñiga-Muñoz ◽  
Rodrigo Velázquez Espejel ◽  
Alfredo Cabrera-Orefice ◽  
...  

We report the effect of cross-sex hormonal replacement on antioxidant enzymes from rat retroperitoneal fat adipocytes. Eight rats of each gender were assigned to each of the following groups: control groups were intact female or male (F and M, resp.). Experimental groups were ovariectomized F (OvxF), castrated M (CasM), OvxF plus testosterone (OvxF + T), and CasM plus estradiol (CasM + E2) groups. After sacrifice, retroperitoneal fat was dissected and processed for histology. Adipocytes were isolated and the following enzymatic activities were determined: Cu-Zn superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and glutathione reductase (GR). Also, glutathione (GSH) and lipid peroxidation (LPO) were measured. In OvxF, retroperitoneal fat increased and adipocytes were enlarged, while in CasM rats a decrease in retroperitoneal fat and small adipocytes are observed. The cross-sex hormonal replacement in F rats was associated with larger adipocytes and a further decreased activity of Cu-Zn SOD, CAT, GPx, GST, GR, and GSH, in addition to an increase in LPO. CasM + E2exhibited the opposite effects showing further activation antioxidant enzymes and decreases in LPO. In conclusion, E2deficiency favors an increase in retroperitoneal fat and large adipocytes. Cross-sex hormonal replacement in F rats aggravates the condition by inhibiting antioxidant enzymes.


1989 ◽  
Vol 66 (2) ◽  
pp. 1003-1007 ◽  
Author(s):  
C. W. White ◽  
P. Ghezzi ◽  
S. McMahon ◽  
C. A. Dinarello ◽  
J. E. Repine

Pretreatment with the combination of tumor necrosis factor/cachectin (TNF/C) and interleukin 1 (IL-1) increased glucose-6-phosphate dehydrogenase (G6PDH), glutathione reductase (GR), glutathione peroxidase (GPX), catalase (CAT), and superoxide dismutase (SOD) activities in lungs of rats continuously exposed to hyperoxia for 72 h, a time when all untreated rats had already died. Pretreatment with TNF/C and IL-1 also increased, albeit slightly, lung G6PDH and GR activities of rats exposed to hyperoxia for 4 or 16 h. By comparison, no differences occurred in lung antioxidant enzyme activities of TNF/C and IL-1- or saline-pretreated rats exposed to hyperoxia for 36 or 52 h; the latter is a time just before untreated rats began to succumb during exposure to hyperoxia. The results raise the possibility that TNF/C and IL-1 treatment can increase lung antioxidant enzyme activities and that increased lung antioxidant enzymes may contribute to the increased survival of TNF/C and IL-1-pretreated rats in hyperoxia for greater than 72 h.


2012 ◽  
Vol 59 (4) ◽  
Author(s):  
Joanna Katarzyna Strzelczyk ◽  
Tomasz Wielkoszyński ◽  
Łukasz Krakowczyk ◽  
Brygida Adamek ◽  
Marzena Zalewska-Ziob ◽  
...  

Oxidative stress is one of several factors which contribute to the development of colorectal carcinogenesis. The aim of the study was an assessment of the activity of antioxidant enzymes in tumour and corresponding normal distal mucosa in a group of patients with colorectal adenocarcinoma. Samples of tumour and corresponding normal mucosa were obtained during a resection of colorectal cancer from 47 patients aged between 26 and 82 years. The average distance of corresponding normal distal mucosa from the tumour was 4.49 cm. Activities of antioxidant enzymes: superoxide dismutase (SOD), glutathione reductase (GR), glutathione peroxidase (GPx), glutathione S-transferase (GST), and catalase (CAT) were measured in tissue homogenates. The patients were grouped according to the tumour stage (Duke's staging), grading, localization, and size of tumour, as well as age and sex. Statistical analysis was performed. The activity of SOD and GPx was considerably increased, while the activity of GST decreased significantly in tumour as compared with normal mucosa. GR activity in colorectal cancer was evidently higher in tumours of proximal location compared with the distal ones. The distance of corresponding normal distal mucosa from the tumour was analyzed and related to all assayed parameters. A decreased GST activity was observed in corresponding normal mucosa more than 5 cm distant from the tumour in patients with CD Duke's stage. The higher activity of superoxide dismutase and glutathione peroxidase in tumour compared to corresponding normal mucosa could indicate higher oxidative stress in colorectal adenocarcinoma cells.


2012 ◽  
Vol 3 (1) ◽  
pp. 18-21 ◽  
Author(s):  
KMK Masthan ◽  
Tajinder Kaur Saggu ◽  
Mahesh Pundaleek Dudanakar ◽  
Shams UI Nisa

ABSTRACT Background Cigarette smoke contains various oxygen-free radicals which are considered as the main causes of damage to biomolecules when exposed to cigarette smoke. Saliva is the first biological fluid that encounters inhaled cigarette smoke (CS) and has an antioxidant defense system able to counter toxic activities of free radical species. So, the aim of this study was to compare the levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in saliva of smokers and nonsmokers. Materials and methods Unstimulated saliva of 200 males (100 smokers and 100 nonsmokers) was collected. The saliva was centrifuged and the activity of salivary superoxide dismutase and glutathione peroxidase was measured according to a specific assay. Results The mean value of superoxide dismutase activity was significantly higher in the smoking group than in the nonsmoker group, while the levels of GSH-Px activity was significantly higher in the nonsmoking group than in the smoking group. Conclusion Cigarette smoke leads to an alteration in salivary antioxidant activity. Evaluating the variations in the level of antioxidant enzymes (SOD and GSH-Px) in smoker's saliva might be useful for estimating the level of oxidative stress caused by cigarette smoke. Thus, it may help in patient's education regarding the ill-effects of smoking and determining the evolution and progress of various oral diseases. How to cite this article Saggu TK, Masthan KMK, Dudanakar MP, Nisa SUI, Patil S. Evaluation of Salivary Antioxidant Enzymes among Smokers and Nonsmokers. World J Dent 2012;3(1):18-21.


Marine Drugs ◽  
2020 ◽  
Vol 18 (9) ◽  
pp. 462
Author(s):  
Xiaoxia Jiang ◽  
Zhexin Ren ◽  
Biying Zhao ◽  
Shuyao Zhou ◽  
Xiaoguo Ying ◽  
...  

Cyclophosphamide (CTX) is a widely used anticancer drug with severe nephrotoxicity. The pentadecapeptide (RVAPEEHPVEGRYLV) from Cyclina sinensis (SCSP) has been shown to affect immunity and to protect the liver. Hence, the purpose of this study was to investigate the ameliorating effect of SCSP on CTX-induced nephrotoxicity in mice. We injected male ICR mice with CTX (80 mg/kg·day) and measured the nephrotoxicity indices, levels of antioxidant enzymes, malondialdehyde (MDA), inflammatory factors, as well as the major proteins of the NF-κB and apoptotic pathways. Cyclophosphamide induced kidney injury; the levels of kidney-injury indicators and cytokines recovered remarkably in mice after receiving SCSP. The activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) increased, while there was a significant decrease in MDA levels. The kidney tissue damage induced by CTX was also repaired to a certain extent. In addition, SCSP significantly inhibited inflammatory factors and apoptosis by regulating the NF-κB and apoptotic pathways. Our study shows that SCSP has the potential to ameliorate CTX-induced nephrotoxicity and may be used as a therapeutic adjuvant to ameliorate CTX-induced nephrotoxicity.


2020 ◽  
pp. ijgc-2020-001587
Author(s):  
Daciele Paola Preci ◽  
Angélica Almeida ◽  
Anne Liss Weiler ◽  
Maria Luiza Mukai Franciosi ◽  
Andréia Machado Cardoso

The pathogenesis of cervical cancer is related to oxidative damage caused by persistent infection by one of the oncogenic types of human papillomavirus (HPV). This damage comes from oxidative stress, which is the imbalance caused by the increase in reactive oxygen and nitrogen species and impaired antioxidant mechanisms, promoting tumor progression through metabolic processes. The incorporation of HPV into the cellular genome leads to the expression of oncoproteins, which are associated with chronic inflammation and increased production of reactive oxygen species, oxidizing proteins, lipids and DNA. The increase in these parameters is related, in general, to the reduction of circulating levels of enzymatic antioxidants—superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase; and non-enzymatic antioxidants—reduced glutathione, coenzyme Q10 and vitamins A, C and E, according to tumor staging. In contrast, some enzymatic antioxidants suffer upregulation in the tumor tissue as a way of adapting to the oxidative environment generated by themselves, such as glutathione-S-transferase, reduced glutathione, glutathione peroxidase, superoxide dismutase 2, induced nitric oxide synthase, peroxiredoxins 1, 3 and 6, and thioredoxin reductase 2. The decrease in the expression and activity of certain circulatory antioxidants and increasing the redox status of the tumor cells are thus key to cervical carcinoma prognosis. In addition, vitamin deficit is considered a possible modifiable risk factor by supplementation, since the cellular functions can have a protective effect on the development of cervical cancer. In this review, we will discuss the impact of oxidative damage on cervical cancer progression, as well as the main oxidative markers and therapeutic potentialities of antioxidants.


1997 ◽  
Vol 17 (5) ◽  
pp. 455-466 ◽  
Author(s):  
Jinn-Yang Chen ◽  
An-Hang Yang ◽  
Yao-Ping Lin ◽  
Jen-Kou Lin ◽  
Wu-Chang Yang ◽  
...  

Objective To investigate the modulation of superoxide dismutase, glutathione peroxidase, and catalase by cytokines and endotoxin in human peritoneal mesothelial cells. Design Cultured human peritoneal mesothelial cells were treated with various concentrations of interleu kin-1 α, tumor necrosis factor-α(TNFα), interleukin-6, interleukin-8, transforming growth factor-β (TGFβ), and lipopolysaccharide. Cell morphology was observed and the activities of superoxide dismutase, catalase, and glutathione peroxidase were assayed. The antioxidant enzyme activities of human peritoneal mesothelial cells were also compared with those of human liver and kidney tissues. Results Interleukin-1α, TNFα, TGFβ, and lipopolysaccharide caused dose-dependent cytotoxicities in mesothelial cells. The activities of these three antioxidant enzymes did not change after treatment with cytokines and endotoxin. The total superoxide dismutase activity of confluent human peritoneal mesothelial cells was found to be greater than that of human liver and kidney tissues and was composed mostly of manganese superoxide dismutase activity. Furthermore, glutathione peroxidase and catalase activities of human peritoneal mesothelial cells were lower than those of human liver and kidney tissues. Conclusion In human peritoneal mesothelial cells, lack of induction of antioxidant enzymes by inflammatory cytokines, as well as high superoxide dismutase activity accompanied by insufficient glutathione peroxidase and catalase activities may both contribute to the susceptibility of these cells to oxidative damage. Therefore, appropriate management to decrease oxidative injury to the peritoneum should be taken into consideration when treating long-term continuous ambulatory peritoneal dialysis patients.


Sign in / Sign up

Export Citation Format

Share Document