Oxidative Stress Markers

Oxidative stress responses as a marker of toxicity in mice exposed to polluted groundwater from an automobile junk market in South-Western Nigeria

The global trade in used vehicles and their components generates huge financial benefits but leads to detrimental environmental consequences including groundwater pollution and potential adverse health effects mediated by free-radical processes such as lipid peroxidation. We investigated oxidative stress responses in thirty-six, female mice orally exposed (via drinking) to graded concentrations (0%, 50%, and 100%) of groundwater from a well located within a major automobile junk market in SW-Nigeria containing extremely high levels of arsenic (0.332 ± 0.089 mg/l) and seventeen PAHs, which serves as domestic water supply. Blood samples from the mice were assayed for selected biochemical parameters at intervals of 7, 14, and 28 days. A significant dose- and duration-dependent increase in malondialdehyde (MDA) and Myeloperoxidase (MPO) confirmed oxidative stress onset due to exposure to the polluted well-water, while a significant decline in nitric oxide (NO-) levels may suggest impaired endothelial smooth-muscle relaxation which may lead to the development of metabolic diseases over time. Superoxide dismutase (SOD) and reduced glutathione (GSH) showed a contrasting trend with Glutathione peroxidase (GPx), while Glutathione-S-Transferase (GST) declined significantly by the 28th day. Two clusters were identified by principal component analysis-one involving MDA, SOD, and GSH suggesting that antioxidant responses driven mainly by SOD and GSH proved insufficient in scavenging the free radicals generated by lipid peroxidation. NO- and total protein clustered together possibly due to the significant declines in both over the study period. Histological examination of liver tissue of exposed mice corroborated the above findings and highlights the need for urgent remedial action.

The Effects of Hyperbaric Oxygenation on Oxidative Stress, Inflammation and Angiogenesis

Hyperbaric oxygen therapy (HBOT) is commonly used as treatment in several diseases, such as non-healing chronic wounds, late radiation injuries and carbon monoxide poisoning. Ongoing research into HBOT has shown that preconditioning for surgery is a potential new treatment application, which may reduce complication rates and hospital stay. In this review, the effect of HBOT on oxidative stress, inflammation and angiogenesis is investigated to better understand the potential mechanisms underlying preconditioning for surgery using HBOT. A systematic search was conducted to retrieve studies measuring markers of oxidative stress, inflammation, or angiogenesis in humans. Analysis of the included studies showed that HBOT-induced oxidative stress reduces the concentrations of pro-inflammatory acute phase proteins, interleukins and cytokines and increases growth factors and other pro-angiogenesis cytokines. Several articles only noted this surge after the first HBOT session or for a short duration after each session. The anti-inflammatory status following HBOT may be mediated by hyperoxia interfering with NF-κB and IκBα. Further research into the effect of HBOT on inflammation and angiogenesis is needed to determine the implications of these findings for clinical practice.

Oxidative stress in response to heat stress in wild caught Namaqua rock mice, Micaelamys namaquensis

Modelling of anthropogenic induced climate suggests more frequent and severe heatwaves in the future, which are likely to result in the mass die-off of several species of organisms. Oxidative stress induced by severe heat stress has previously been associated with a reduction in animal cognitive performance, depressed reproduction and lower life expectancy. Little is known about the non-lethal consequences of species should they survive extreme heat exposure. We investigated the oxidative stress experienced by the Namaqua rock mouse, a nocturnal rodent, using two experimental heat stress protocols, a 6 hour acute heat stress protocol without access to water and a 3-day heatwave simulation with ad libitum water. Oxidative stress was determined in the liver, kidney and brain using malondialdehyde (MDA) and protein carbonyl (PC) as markers of oxidative damage, and superoxide dismutase (SOD) and total antioxidant capacity (TAC) as markers of antioxidant defence. Incubator heat stress (heat and dehydration stress) was brought about by increasing the body temperatures of animals to 39-40.8 °C for 6 hours. Following incubator heat stress, significantly higher levels of MDA were observed in the liver. Dehydration did not explain the variation in oxidative markers and is likely a combined effect of thermal and dehydration stress. Individual body mass was significantly negatively correlated to kidney SOD and lipid peroxidation. A heatwave was simulated using a temperature cycle that would naturally occur during a heatwave in the species' local habitat, with a maximal ambient temperature of 38 °C. Following the simulated heatwave, SOD activity of the kidney demonstrated significantly lowered activity suggesting oxidative stress. Current heat waves in this species have the potential of causing oxidative stress. Heat and dehydration stress following exacerbated temperatures are likely to incur significant oxidative stress in multiple tissues demonstrating the importance of water availability to allow for rehydration to prevent oxidative stress.

Ischemia-modified albumin in gynecology

Background: Ischemia-modified albumin (IMA) is an oxidative stress marker used to assess the presence and severity of oxidative stress. This marker was first used for early diagnosis of myocardial ischemia. Materials & methods: A variety of IMA studies were carried out to show the effect of oxidative stress on gynecological disorders. Conclusion: This analysis summarizes the literature by conducting electronic research on the relationship between IMA and gynecological disorders.

Honey and its nutritional and anti-inflammatory value

Inflammation is the main key role in developing chronic diseases including cancer, cardiovascular diseases, diabetes, arthritis, and neurodegenerative diseases which possess a huge challenge for treatment. With massively compelling evidence of the role played by nutritional modulation in preventing inflammation-related diseases, there is a growing interest into the search for natural functional foods with therapeutic and preventive actions. Honey, a nutritional healthy product, is produced mainly by two types of bees: honeybee and stingless bee. Since both types of honey possess distinctive phenolic and flavonoid compounds, there is recently an intensive interest in their biological and clinical actions against inflammation-mediated chronic diseases. This review shed the light specifically on the bioavailability and bioaccessibility of honey polyphenols and highlight their roles in targeting inflammatory pathways in gastrointestinal tract disorders, edema, cancer, metabolic and cardiovascular diseases and gut microbiota.

Heat and dehydration induced oxidative damage and antioxidant defenses following incubator heat stress and a simulated heat wave in wild caught four-striped field mice Rhabdomys dilectus

Heat waves are known for their disastrous mass die-off effects due to dehydration and cell damage, but little is known about the non-lethal consequences of surviving severe heat exposure. Severe heat exposure can cause oxidative stress which can have negative consequences on animal cognition, reproduction and life expectancy. We investigated the current oxidative stress experienced by a mesic mouse species, the four striped field mouse, Rhabdomys dilectus through a heat wave simulation with ad lib water and a more severe temperature exposure with minimal water. Wild four striped field mice were caught between 2017 and 2019. We predicted that wild four striped field mice in the heat wave simulation would show less susceptibility to oxidative stress as compared to a more severe heat stress which is likely to occur in the future. Oxidative stress was determined in the liver, kidney and brain using malondialdehyde (MDA) and protein carbonyl (PC) as markers for oxidative damage, and superoxide dismutase (SOD) and total antioxidant capacity (TAC) as markers of antioxidant defense. Incubator heat stress was brought about by increasing the body temperatures of animals to 39-40.8°C for 6 hours. A heat wave (one hot day, followed by a 3-day heatwave) was simulated by using temperature cycle that wild four striped field mice would experience in their local habitat (determined through weather station data using temperature and humidity), with maximal ambient temperature of 39°C. The liver and kidney demonstrated no changes in the simulated heat wave, but the liver had significantly higher SOD activity and the kidney had significantly higher lipid peroxidation in the incubator experiment. Dehydration significantly contributed to the increase of these markers, as is evident from the decrease in body mass after the experiment. The brain only showed significantly higher lipid peroxidation following the simulated heat wave with no significant changes following the incubator experiment. The significant increase in lipid peroxidation was not correlated to body mass after the experiment. The magnitude and duration of heat stress, in conjunction with dehydration, played a critical role in the oxidative stress experienced by each tissue, with the results demonstrating the importance of measuring multiple tissues to determine the physiological state of an animal. Current heat waves in this species have the potential of causing oxidative stress in the brain with future heat waves to possibly stress the kidney and liver depending on the hydration state of animals.

Behavioral and biochemical effects of the antifouler and antidandruff zinc pyrithione on the freshwater fish Gambusia holbrooki

The presence of pharmaceutical residues in the aquatic environment is receiving great attention since the levels of these substances have significantly increased in this compartment, potentially leading to adverse ecological effects. Zinc pyrithione (ZnPt) is a widely used organometallic biocide, which is incorporated into antifouling formulas, such as paints, to prevent the establishment of biofilms on surfaces exposed to the aquatic environment. It is also used in cosmetics, such as antidandruff shampoos and soaps. Considering this wide use, and the absence of a significant amount of data on the toxicity of ZnPt especially towards non-target organisms, the objective of this study was to characterize the toxicity of ZnPt, on several ecological relevant endpoints assessed in the fish Gambusia holbrooki. For this purpose, we measured traits related to feeding and aggressive behavior, as well as indicators of oxidative stress (CAT and GSTs), neurotoxicity (AChE), and anaerobic metabolism (LDH), after acute and chronic exposures to ZnPt. In terms of behavioral features, the feeding test showed the occurrence of significant differences between the control animals and those exposed to a concentration of ZnPt of 45 μg/L. In addition, ZnPt caused changes in terms of oxidative stress biomarkers (CAT and GSTs), for both exposure periods. ZnPt was also capable of causing changes in the cholinergic neurotransmission functioning and anaerobic metabolism, but only following the chronic exposure.

Evaluation of oxidative stress and antioxidant capacity in healthy children

BACKGROUND

Measurement of the levels of the derivatives of reactive oxygen metabolites (d-ROMs) and of the biological antioxidant potential (BAP) enables simultaneous assessment of oxidation degree and antioxidant capacity, using the same sample and testing equipment. At present, reference values of healthy adults are clarified, but the reference value of healthy children is unknown. This study was undertaken to clarify the age-related changes and the reference values of d-ROMs and BAP in healthy children.

METHODS

The study population consisted of 77 children, ranging in age from 2 to 15 years, in normal mental and physical health as examined by a pediatrician, and seven healthy adult volunteers. Serum samples were obtained from the subjects for assay. Using these samples, d-ROMs and BAP values were measured, and the relationship with age was analyzed.

RESULTS

The d-ROMs level decreased as the age increased, while the BAP showed no correlation with the age. The d-ROMs level was significantly higher in 2-6 years group than in 7-11 years group, 12-15 years group, or healthy adults group. The BAP/d-ROMs ratio, an index of antioxidant capacity, increased significantly with higher age.

CONCLUSION

This study was carried out for the first time in healthy children in oxidative stress assessment using d-ROMs and BAP. In the infancy 2-6 years, the d-ROMs value was significantly higher and the BAP/d-ROMs ratio was significantly lower. From this, it was suggested that age should be considered when performing oxidative stress assessment using d-ROMs and BAP in children.

The Impact of Repetitive Transcranial Magnetic Stimulation on Oxidative Stress in Subjects With Medication-Resistant Depression

OBJECTIVES

Recent studies have shown that oxidative stress is involved in the neurobiology of depression. We investigated the effects of repetitive transcranial magnetic stimulation (rTMS) on a novel oxidative stress marker, thiol-disulfide homeostasis, in subjects with medication-resistant major depression (MRD).

METHODS

Twenty-six subjects with MRD underwent 15 rTMS sessions. Sociodemographic and baseline and post-rTMS Montgomery-Asberg Depression Rating Scale (MADRS) data were collected. Serum levels of native thiol, total thiol, and disulfide and their pairwise ratios were measured in baseline and post-rTMS blood samples.

RESULTS

Serum levels of native and total thiol were significantly decreased after rTMS treatment (P < 0.05). Serum levels of thiol-disulfide and their ratios did not significantly differ (P > 0.05) between rTMS treatment responders (>50% reduction in MADRS score, n = 11) and rTMS treatment nonresponders (n = 15). The percentage MADRS score changes did not correlate with the changes in the levels of serum thiol-disulfide from baseline to post-rTMS treatment in any subject (P > 0.05).

CONCLUSIONS

Our results showed that rTMS treatment was effective in subjects with MRD and was associated with changes in serum thiol levels regardless of improvement in depression severity. Thus, the results did not support a possible therapeutic relationship between rTMS and thiol-disulfide homeostasis in subjects with MRD.

Changes in oxidative stress severity and antioxidant potential during muscle atrophy and reloading in mice

[Purpose] Changes in oxidative stress severity and antioxidant potential are routinely used as oxidative stress markers. While several studies have reported the relationship between these markers and exercise, little is known about the dynamic nature of these markers during muscle atrophy and reloading. Therefore, we examined changes in oxidative stress severity and antioxidant potential during muscle atrophy and reloading. [Subjects and Methods] Muscle atrophy was induced in mice by casting the limb for 2 weeks. Mice were then subjected to reloading for 2 weeks. The severity of oxidative stress (hydroperoxide) and antioxidant potential (degree of reduction) were quantified. [Results] Muscle atrophy was induced by cast immobilization. The muscle mass of mice recovered to similar levels as the control group following 2 weeks of reloading. The degree of oxidative stress was within the normal range throughout the experimental period. The antioxidant potential decreased to the clinical borderline level 2 weeks after immobilization, further decreased after 1 day of reloading, and then recovered to within the normal range. [Conclusion] Performing d-ROMs and BAP tests may contribute to the understanding to atrophic process of skeletal muscle in clinical practice of physical therapy.

Evaluation of oxidative stress in caprine bronchoalveolar lavage fluid of pneumonic and normal lungs

Research in the area of oxidative stress in pneumonic pathology still requires attention in small ruminants especially with the use of bronchoalveolar lavage (BAL) which may be a more sensitive indicator of respiratory diseases than blood. This investigation evaluates the role of oxidative stress in the pathogenesis of caprine pneumonia using BAL fluid (BALf) from healthy and pneumonic goats. A BALf from 192 goats (whose pneumonic histopathology had been characterized using standard techniques) was biochemically assayed for anti-oxidants and pro-oxidants. Malondialdehyde (MDA), hydrogen peroxide generation (H₂O₂), myeloperoxidase (MPO) and reduced glutathione (GSH) contents were measured to assess free radical activity in the BALf. Superoxide dismutase (SOD), Glutathione transferase (GST) and Glutathione peroxidase (GPx) activity were also determined colourimetrically. There were significant increases in the BALf supernatant of MDA, H₂O₂ and MPO with decreases in GSH level and SOD activity in the pneumonic goats (P < 0.05). There was also significant correlation of BALf oxidative assay to the type and severity of pneumonia. The levels of MDA, H₂O_2, and MPO increased significantly (P < 0.05) in bronchopneumonia and bronchointerstitial pneumonia than other pneumonic conditions and normal lungs. The management of caprine pneumonia should often incorporate antioxidant supplementation to correct the imbalance in pro-oxidant and anti-oxidant levels.

Total antioxidant and total oxidant states, and serum paraoxonase-1 in neonatal sepsis

BACKGROUND

Paraoxonase-1 (PON-1) is an enzyme with a glycoprotein structure that depends on calcium and which is located in serum high-density lipoprotein (HDL). The aim of this study was to evaluate PON-1, and oxidant/antioxidant state, before and after treatment for neonatal sepsis, and to determine the usability of PON-1 in neonatal sepsis treatment.

METHODS

A total of 35 neonatal sepsis patients and 35 healthy controls were included in the study. Activity of PON-1, total oxidant state (TOS) and total antioxidant state (TAS) were measured and oxidative stress index (OSI) was calculated.

RESULTS

In the neonatal sepsis patients, pre-treatment TAS, TOS and OSI were significantly higher than the post-treatment levels (P < 0.0001, P < 0.0001 and P < 0.0001, respectively), and PON-1 was significantly lower (P < 0.0001). Similarly, pre-treatment TAS, TOS and OSI in the sepsis group were also significantly higher than in the control group (P < 0.0001, P < 0.0001 and P < 0.0001, respectively) and PON-1 was significantly lower (P < 0.0001). Post-treatment TAS in the sepsis group was significantly higher than in the control group (P = 0.009), whereas post-treatment TOS, OSI and PON-1 in the sepsis group were not significantly different to the control group (P = 0.078, P = 0.597 and P = 0.086, respectively).

CONCLUSION

Low serum PON-1 was found in neonatal sepsis. Serum PON-1 is thought to be a useful biomarker to evaluate the effectiveness of treatment and recovery in neonatal sepsis.

Reproduction is associated with a tissue-dependent reduction of oxidative stress in eusocial female Damaraland mole-rats (Fukomys damarensis)

Oxidative stress has been implicated as both a physiological cost of reproduction and a driving force on an animal's lifespan. Since increased reproductive effort is generally linked with a reduction in survival, it has been proposed that oxidative stress may influence this relationship. Support for this hypothesis is inconsistent, but this may, in part, be due to the type of tissues that have been analyzed. In Damaraland mole-rats the sole reproducing female in the colony is also the longest lived. Therefore, if oxidative stress does impact the trade-off between reproduction and survival in general, this species may possess some form of enhanced defense. We assessed this relationship by comparing markers of oxidative damage (malondialdehyde, MDA; protein carbonyls, PC) and antioxidants (total antioxidant capacity, TAC; superoxide dismutase, SOD) in various tissues including plasma, erythrocytes, heart, liver, kidney and skeletal muscle between wild-caught reproductive and non-reproductive female Damaraland mole-rats. Reproductive females exhibited significantly lower levels of PC across all tissues, and lower levels of MDA in heart, kidney and liver relative to non-reproductive females. Levels of TAC and SOD did not differ significantly according to reproductive state. The reduction in oxidative damage in breeding females may be attributable to the unusual social structure of this species, as similar relationships have been observed between reproductive and non-reproductive eusocial insects.

Reactive nitrogen and oxygen species in anticoagulated blood of healthy sheep

BACKGROUND

Little or no study has been done to compare the indices of 'nitrosative' and 'oxidative' stresses, especially in terms of correlation and the possible differential effects of the chelating agents.

OBJECTIVE

This preliminary study investigated possible correlations between the indices of reactive nitrogen species (RNS) and reactive oxygen species (ROS) in blood, effect of anticoagulated-blood tubes, and impact of blood-clotting pathways.

METHODS

Thirty blood samples from sheep were collected into ethylenediamine tetraacetic acid (EDTA) and citrate tubes at the Berrima Veterinary Laboratory using their standard protocol. Nitrosative and oxidative stress indices were then measured and correlation analyses performed.

RESULTS

The ROS and RNS indices were weakly correlated (r > 0.2; p < 0.05) with each other from the EDTA sample, but not from citrated blood. None of the nitrosative or oxidative stress biomarkers was significantly associated with changes in the prothrombin time. The activated partial thromboplastin time showed statistically significant association with some oxidative stress indices (catalase and malondialdehyde), but with none of the nitrosative stress indices. Further, all measured parameters were higher in EDTA than in citrate blood (p < 0.0001).

CONCLUSION

The choice of anticoagulated blood tube could affect the measures of nitrosative stress indices and may impact on the potential correlations between nitrosative versus oxidative stress biomarkers. Perhaps the suggestion that EDTA is better than citrate for hematological anticoagulant studies should be considered for nitrosative and oxidative stress studies.