scholarly journals Heat Killing of Bacillus subtilis Spores in Water Is Not Due to Oxidative Damage

1998 ◽  
Vol 64 (10) ◽  
pp. 4109-4112 ◽  
Author(s):  
Barbara Setlow ◽  
Peter Setlow

ABSTRACT The heat resistance of wild-type spores of Bacillus subtilis or spores (termed α−β−) lacking DNA protective α/β-type small, acid-soluble spore proteins was not altered by anaerobiosis or high concentrations of the free radical scavenging agents ethanethiol and ethanedithiol. Heat-killed wild-type and α−β− spores exhibited no increase in either protein carbonyl content or oxidized bases in DNA. These data strongly suggest that oxidative damage to spore macromolecules does not contribute significantly to spore killing by heat.

1993 ◽  
Vol 13 (1) ◽  
pp. 145-152 ◽  
Author(s):  
Jaroslava Folbergrová ◽  
Yoshihiro Kiyota ◽  
Kerstin Pahlmark ◽  
Hajime Memezawa ◽  
Maj-Lis Smith ◽  
...  

Recent results suggest that even relatively brief periods of ischemia in gerbils (10 min) lead to oxidative damage to brain proteins, reflected in an increased carbonyl content in the soluble protein fraction and a decreased glutamine synthetase (GS) activity. Since we failed to reproduce these findings in rats subjected to 15 min of transient ischemia, we explored whether oxidative damage to proteins could be observed after longer ischemic periods. To that end, one middle cerebral artery was occluded in rats for either 1 or 3 h, with recirculation periods of 0 min, 15 min, 1 h, and 6 h. Protein carbonyl content and GS activity were determined in focal and perifocal tissues and compared with values obtained in the same areas on the contralateral side. Ischemia, particularly of 3-h duration, followed by various reperfusion periods was accompanied by a significant (16–35%) decrease in the concentration of proteins of the soluble protein fraction. However, in no group was there an increased carbonyl content of the remaining proteins in this fraction. When expressed per milligram of protein, GS activity remained unchanged or rose somewhat. An inconsistent (and moderate) decrease in GS activity was present only if GS activity was expressed per milligram of wet tissue. The present findings, which fail to document oxidative damage to proteins following focal ischemia of 1- or 3-h duration, are thus radically different from those obtained in gerbils. The results suggest that appreciable species differences exist and raise the question of whether free radical–mediated oxidation of proteins is an invariable component of ischemic brain damage.


2019 ◽  
Vol 2 (2) ◽  
pp. 1-21 ◽  
Author(s):  
Elina Mitra ◽  
Bharati Bhattacharjee ◽  
Palash Kumar Pal ◽  
Arnab Kumar Ghosh ◽  
Sanatan Mishra ◽  
...  

Cadmium (Cd) is a notorious environmental pollutant known for its wide range of toxicities to organisms. Thus, the present study is designed to examine whether melatonin, a potent antioxidant, protects against Cd-induced oxidative damage in the heart, liver and kidney of rats. Cd treatment at a dose of 0.44 mg/kg for 15 days caused severe damage in all these organs. These included significantly increased activities of SGPT, SGOT, lactate dehydrogenase- 1 and 5 and ALP and levels of total lactate, creatinine, lipid peroxidation, protein carbonyl content and reduced glutathione while the activities of superoxide dismutases, catalase, glutathione peroxidase, glutathione reductase and glutathione-S-transferase along with mitochondrial pyruvate dehydrogenase, isocitrate dehydrogenase, α-keto glutarate dehydrogenase, succinate dehydrogenase, NADH-cytochrome-c-oxidoreductase and cytochrome-c-oxidase were significantly reduced by Cd. However, if melatonin was given orally 30 min before Cd injection, all these alterations induced by Cd were significantly preserved by melatonin. Histological observations also demonstrated that Cd exposure caused cellular lesions, promoting necrotic or apoptotic changes. Notably, all these changes were significantly protected by melatonin. The results suggest that melatonin is a beneficial molecule to ameliorate Cd-induced oxidative damage in the heart, liver and kidney tissues of rats with its powerful antioxidant capacity, heavy metal chelating activity and competition of binding sites with Cd to the GSH and catalase.


2020 ◽  
Vol 70 (2) ◽  
pp. 227-237
Author(s):  
Eda Güneş

Abstract The aim of the this study was to evaluate the effects of fresh, dried and freeze-dried Centaurea depressa M. Bieb. (Asteraceae) on the oxidant and antioxidant status of the model organism D. melanogaster Meigen (Diptera: Drosophilidae) experimentally. The study was carried out from 2016 to 2019, and plant leaf extracts (0-50 mg/l) were added to insect standard artificial diets. The total protein, protein carbonyl content and glutathione-S-transferase, superoxide dismutase and catalase activities were quantified at the insect’s third larval stage. Our data showed that protein carbonyl content varied from 2.70 nmol/mg protein in the control group to 59.11 nmol/mg protein in the group fed with fresh leaf extract signifying induction of oxidative stress. All extracts increased the levels of all antioxidant enzymes and decreased the amounts of total protein. Meanwhile, the group fed with the freeze-dried extract showed no significant difference in the levels of total protein and protein carbonyl content except at the 50 mg/l concentration of the extract. Moreover, this group had superoxide dismutase and catalase activities 4 to 5 times higher than in the control group. In conclusion, induction of oxidative stress indicates that the fresh form of C. depressa leaves may have potential as a natural pesticide, whereas induction of endogenous antioxidant enzymes by the freeze-dried extract suggest its potential as an antioxidant.


Author(s):  
Pullaiah P. ◽  
Suchitra M. M. ◽  
Siddhartha Kumar B.

Background: Oxidative stress (OS) has an important role in the pathogenesis and progression of rheumatoid arthritis (RA). OS causes protein modification, thereby impairing the biological functions of the protein. This study was conducted to assess the oxidatively modified protein as protein carbonyl content and the antioxidant status as protein thiols, and to study the association between protein carbonyls and protein thiols in RA.Methods: Newly diagnosed RA patients who were not taking any disease modifying anti-rheumatic drugs were included into the study group (n=45) along with age and sex matched healthy controls (n=45). Serum protein carbonyl content and protein thiols were estimated.Results: Elevated protein carbonyl content and decreased protein thiol levels (p<0.001) were observed in RA. A significant negative correlation was observed between protein carbonyl content and protein thiol levels (p<0.001).Conclusions: Oxidative stress in RA is evidenced by enhanced protein oxidation and decreased antioxidant protein thiol levels. Decreased protein thiols may also reflect protein modifications leading to compromise in the antioxidant properties. This oxidant and antioxidant imbalance needs to be addressed by therapeutic interventions to prevent disease progression.


2012 ◽  
Vol 1 (3) ◽  
pp. 200 ◽  
Author(s):  
Sarawut Kumphune ◽  
Titiporn Mekrungruangwong ◽  
Porrnthanate Seenak ◽  
Saowanee Luangaram ◽  
Tomon Thongsri

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3319-3319
Author(s):  
Clara Lo ◽  
Bing Zhang ◽  
Kristina Cusmano-Ozog ◽  
Wendy Wong ◽  
Michael Jeng ◽  
...  

Abstract Abstract 3319 Background: An unpredictable subset of patients (∼20–30%) with pediatric immune thrombocytopenia (ITP) progress to chronic ITP; this increases the risk of morbidity and mortality from bleeding, long-term immunomodulation, and/or splenectomy. Furthermore, treatments such as chronic steroid therapy often result in intolerable side effects, raising the need for targeted therapies. We previously tested a novel list of genes that might predict progression to chronic ITP (Zhang et al Blood 2011). Oxidative stress (OS)-related pathways were among those most significantly perturbed in chronic ITP. For further evaluation of the role of OS in ITP, we measured glutathione as a marker of redox capacity and protein carbonyl content as a marker of oxidative cell damage. Methods: Pediatric patients with primary ITP were included, with exclusion of subjects with secondary thrombocytopenia, other autoimmune disorders (ie, lupus), or other chronic illnesses. Healthy pediatric volunteers were recruited as controls. Patients had blood draws within 1 month from ITP diagnosis. Reduced (GSH) to oxidized (GSSG) glutathione ratios were measured from whole blood by tandem mass-spectrometry. Protein carbonyl content (PCC) levels were measured from platelet-rich plasma by enzyme-linked immunosorbent assay (ELISA). Subjects were followed up to 15 months from diagnosis and monitored for disease resolution or progression. Chronic ITP was defined as thrombocytopenia (platelets <100,000/μL) lasting at least 12 months from diagnosis (Rodegheiro et al Blood 2009). Acute ITP was defined as thrombocytopenia resolving within 12 months from diagnosis. Statistical significance was defined as p<0.05. Results: Between July 2009 and December 2011, 67 pediatric patients with ITP were recruited. Thirty-four patients had acute ITP, and 33 patients progressed to chronic ITP. The median age of patients was 7 years (range 18 months – 17 years). Sixty-three percent were female, 37% were male. Twenty-four pediatric controls were also recruited (46% female, 54% male). The median age of controls was 8 years (range 5 years – 17 years). Patients with ITP had significantly lower GSH:GSSG ratios compared to controls, and patients with chronic ITP had lower GSH:GSSG ratios compared to those with acute ITP (Figure 1). Furthermore, patients with ITP had significantly higher PCC levels compared to controls (Figure 2). Conclusions: This data provides further evidence for a role of oxidative stress (OS) in the pathophysiology of ITP. Furthermore, decreased redox capacity, as evidenced by the decreased glutathione ratios, may be associated with progression to chronic ITP. Reactive oxidative species (ROS) may be important in the pathogenesis of autoimmunity in ITP; oxidatively altered cellular by-products induce pathogenic antibodies and become immunogenic. This also raises a potential anti-oxidant mechanism of therapy, which may play a greater role in chronic ITP treatment. Increased understanding of OS in pediatric ITP may reveal markers of disease progression, highlighting those at greatest risk for chronic ITP and creating a role for targeted therapy. Disclosures: No relevant conflicts of interest to declare.


2006 ◽  
Vol 164 ◽  
pp. S136
Author(s):  
Vügar Aliyev ◽  
Banuçiçek Yücesan ◽  
Şebnem Ş. Çeçen ◽  
Ayşe Karakuş ◽  
Serap Yalçın ◽  
...  

2014 ◽  
Vol 68 (10) ◽  
Author(s):  
Mária Baňasová ◽  
Katarína Valachová ◽  
Ivo Juránek ◽  
Ladislav Šoltés

AbstractOxidative stress and the resulting damage to cellular and extracellular components has been observed in a variety of degenerative processes, including degenerative joint disorders, where high-molar-mass hyaluronan (HA) is often found to be massively degraded. The present study sought to test the hypothesis that dithiols are more effective in protecting biomacromolecules from free-radicalmediated damage than monothiols. The materials/thiols tested included bucillamine (BUC), dithioerythritol (DTE), dithiothreitol (DTT) and glutathione (GSH), as a reference, for their effectiveness in protecting HA from oxidative degradation induced in vitro. Since HA degradation results in a decrease in its dynamic viscosity, rotational viscometry was applied to follow HA oxidative degradation. The free-radical-scavenging activities of the thiols tested were determined by 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) and di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) assays. It was found that all the dithiols in the concentration range tested protected HA from the oxidative degradation. On the other hand, monothiol GSH exerted protection only at high concentrations (10 μmol L−1 and 100 μmol L−1) and 1 μmol L−1 of GSH even exhibited a prodegradative effect. The ABTS assay revealed free-radical scavenging activities in the following order: BUC, DTT, DTE, GSH, and that of the DPPH assay: BUC, DTE, DTT, GSH. In conclusion, it was demonstrated that dithiols may be more effective than monothiols in affording biomacromolecule protection from oxidative degradation.


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