Elevation in the ratio of Cu/Zn-superoxide dismutase to glutathione peroxidase activity induces features of cellular senescence and this effect is mediated by hydrogen peroxide

Assessing antioxidant responses in C6 and U-87 MG cell lines exposed to high copper levels

Copper excess has been tested as an anticancer therapy, due to its properties to generate oxidative stress resulting in tumoral cell death. Thus, this study aimed to evaluate the impact of copper excess on oxidative stress and antioxidant responses in glioma cells, establishing the antioxidant system as a target of copper toxicity in tumoral cells. C6 and U-87 MG cells were exposed to CuSO4 (0-600 μM) for 24-48 h. SOD, CAT, GPx, GR, and CK activities, protein and non-protein thiol levels (PSH and NPSH), and O2- production were assessed, alongside SOD1, GPx1, and GR gene expression. Results revealed a decrease in GPx, GR, and CAT activity after CuSO4 exposure in both cell lines over 24-48 h, while SOD activity initially increased, then declined after 48 h. CK activity was also decreased in C6 cells. NPSH and PSH levels dropped after 24 h, and O2- production was observed in all CuSO4 concentrations. GR mRNA was reduced in both cell lines, contrasting with increased GPx1 mRNA in C6. U-87 MG cells exhibited higher levels of SOD1 mRNA, while C6 cells displayed lower expression. Our findings suggest that copper excess limits antioxidant enzyme activity and thiol levels, particularly in the C6 cells, likely attributable to oxidative stress or direct copper-enzyme interactions. Moreover, our results imply differences in copper toxicity regarding the cell lineage used, highlighting the importance of analyzing high copper levels effects in different models. Moreover, it could be proposed that the antioxidant system is a target of copper toxicity, contributing to glioma cell death.

Down syndrome and leukemia: An insight into the disease biology and current treatment options

Children with Down syndrome (DS) have a 10- to 20-fold greater predisposition to develop acute leukemia compared to the general population, with a skew towards myeloid leukemia (ML-DS). While ML-DS is known to be a subtype with good outcome, patients who relapse face a dismal prognosis. Acute lymphocytic leukemia in DS (DS-ALL) is considered to have poor prognosis. The relapse rate is high in DS-ALL compared to their non-DS counterparts. We have a better understanding about the mutational spectrum of DS leukemia. Studies using animal, embryonic stem cell- and induced pluripotent stem cell-based models have shed light on the mechanism by which these mutations contribute to disease initiation and progression. In this review, we list the currently available treatment strategies for DS-leukemias along with their outcome with emphasis on challenges with chemotherapy-related toxicities in children with DS. We focus on the mechanisms of initiation and progression of leukemia in children with DS and highlight the novel molecular targets with greater success in preclinical trials that have the potential to progress to the clinic.

Effects of Regular Exercise and Intermittent Fasting on Neurotransmitters, Inflammation, Oxidative Stress, and Brain-Derived Neurotrophic Factor in Cortex of Ovariectomized Rats

A collection of metabolic disorders and neurodegenerative diseases linked to oxidative stress and neuroinflammation frequently affect postmenopausal women or estrogen deprivation. Recent research has focused on alternative therapies that can enhance these women's quality of life. This study set out to investigate the effects of physical exercise (EX) and intermittent fasting (IF) on oxidants/antioxidants, inflammatory cytokines, neurotransmitters, and brain-derived neurotrophic factor (BDNF) in the cortex of rats. Additionally, it sought to assess the response to oxidative stress and neuroinflammation in the brains of rats following ovariectomy (OVX) and the potential mechanisms of these interventions. Fifty female rats were divided into one of the following groups 30 days after bilateral OVX: Control, OVX, OVX + EX, OVX + IF, and OVX + EX + IF groups. The rats in the Control and OVX groups continued their normal activities and had unrestricted access to food and water, but the rats in the OVX + EX and OVX + EX + IF groups had a 4-week treadmill training program, and the rats in the OXV + IF and OVX + EX + IF groups fasted for 13 h each day. The rats were killed, the cerebral cortex was taken, tissue homogenates were created, and various parameters were estimated using these homogenates. The results show that ovariectomized rats had decreased levels of neurotransmitters (DA, NE, and SE), acetylcholinesterase, brain GSH (glutathione), SOD (superoxide dismutase), catalase, GPx (glutathione peroxidase), and TAC (total antioxidant capacity), as well as elevated levels of proinflammatory cytokines and mediators (TNF-α, IL-1β, Cox-2). While ovariectomy-induced declines in neurotransmitters, enzymatic and nonenzymatic molecules, neuroinflammation, and oxidative brain damage were considerably mitigated and prevented by treadmill exercise and intermittent fasting, BDNF was significantly increased. These results suggest that ovariectomy can impair rat neuronal function and regular treadmill exercise and intermittent fasting seem to protect against ovariectomy-induced neuronal impairment through the inhibition of oxidative stress and neuroinflammation and increased BDNF levels in the brain cortex. However, combining regular exercise and intermittent fasting did not provide additional benefits compared to either treatment alone.

Is microglial dystrophy a form of cellular senescence? An analysis of senescence markers in the aged human brain

Aging can cause morphological transformation in human microglia indicative of cell senescence, termed microglial dystrophy. However, cellular senescence is characterized by additional changes, such as an irregular cell cycle arrest, and a variety of metabolic and molecular changes including a senescence-associated secretory phenotype, dysfunction of degradation mechanisms, and altered DNA damage response. Here, we tested whether dystrophic microglia display customary markers of cell senescence by performing double and triple staining in sections of the temporal lobe and brain stem from 14 humans. We found that markers related to oxidative damage, such as upregulation of 8-hydroxy-2'-deoxyguanosine (8-OHdG), hemeoxygenase-1 (HO-1), and y-H2AX, as well as inclusion of lipofuscin, do not or only exceptionally colocalize with dystrophic microglia. Further, we did not observe a decline in lamin B1 around nuclear laminae in either dystrophic or ramified microglia within the same microscopic field. Only ferritin expression, which is known to increase with aging in CNS microglia, was frequently observed in dystrophic, but rarely in ramified microglial cells. We conclude that neither dystrophic nor ramified microglia in human brain exhibit significant expression of conventional senescence markers associated with oxidative stress, and that ferritin is the dominant immunophenotypic change related to microglial aging. We suggest that multiple pathogenic mechanisms other than those driving cellular senescence contribute to dystrophic transformation of microglia.

An Insight into the Impact of Serum Tellurium, Thallium, Osmium and Antimony on the Antioxidant/Redox Status of PCOS Patients: A Comprehensive Study

Humans exploit heavy metals for various industrial and economic reasons. Although some heavy metals are essential for normal physiology, others such as Tellurium (Te), Thallium (TI), antimony (Sb), and Osmium (Os) are highly toxic and can lead to Polycystic Ovarian Syndrome (PCOS), a common female factor of infertility. The current study was undertaken to determine levels of the heavy metals TI, Te, Sb and Os in serum of PCOS females (n = 50) compared to healthy non-PCOS controls (n = 56), and to relate such levels with Total Antioxidant Capacity (TAC), activity of key antioxidant enzymes, oxidative stress marker levels and redox status. PCOS serum samples demonstrated significantly higher levels of TI, Te, Sb and Os and diminished TAC compared to control (p < 0.001). Furthermore, there was significant inhibition of SOD, CAT and several glutathione-related enzyme activities in sera of PCOS patients with concurrent elevations in superoxide anions, hydrogen and lipid peroxides, and protein carbonyls, along with disrupted glutathione homeostasis compared to those of controls (p < 0.001 for all parameters). Additionally, a significant negative correlation was found between the elevated levels of heavy metals and TAC, indicative of the role of metal-induced oxidative stress as a prominent phenomenon associated with the pathophysiology of the underlying PCOS. Data obtained in the study suggest toxic metals as risk factors causing PCOS, and thus protective measures should be considered to minimize exposure to prevent such reproductive anomalies.

Ergothioneine and its prospects as an anti-ageing compound

Healthy ageing is a crucial process that needs to be highlighted as it affects the quality of lifespan. An increase in oxidative stress along with ageing is the major factor related to the age-associated diseases, especially neurodegenerative disorders. An antioxidant-rich diet has been proven to play a significant role in the ageing process. Targeting ageing mechanisms could be a worthwhile approach to improving health standards. Ergothioneine (EGT), a hydrophilic compound with specific transporter known as OCTN1, has been shown to exert anti-ageing properties. In addition to its antioxidant effect, EGT has been reported to have anti-senescence, anti-inflammatory and anti-neurodegenerative properties. This review aims to define the pivotal role of EGT in major signalling pathways in ageing such as insulin/insulin-like growth factor (IGF) signalling (IIS), sirtuin 6 (SIRT6) and mammalian target of rapamycin complex (mTOR) pathways. The review further discusses evidence of EGT on neurodegeneration in its therapeutic context in various model organisms, providing new insights into improving health. In conclusion, an ergothioneine-rich diet may be beneficial in preventing age-related diseases, resulting in a healthy ageing population.

Role of Oxidative Stress in Liver Disorders

Oxygen is vital for life as it is required for many different enzymatic reactions involved in intermediate metabolism and xenobiotic biotransformation. Moreover, oxygen consumption in the electron transport chain of mitochondria is used to drive the synthesis of ATP to meet the energetic demands of cells. However, toxic free radicals are generated as byproducts of molecular oxygen consumption. Oxidative stress ensues not only when the production of reactive oxygen species (ROS) exceeds the endogenous antioxidant defense mechanism of cells, but it can also occur as a consequence of an unbalance between antioxidant strategies. Given the important role of hepatocytes in the biotransformation and metabolism of xenobiotics, ROS production represents a critical event in liver physiology, and increasing evidence suggests that oxidative stress contributes to the development of many liver diseases. The present review, which is part of the special issue “Oxidant stress in Liver Diseases”, aims to provide an overview of the sources and targets of ROS in different liver diseases and highlights the pivotal role of oxidative stress in cell death. In addition, current antioxidant therapies as treatment options for such disorders and their limitations for future trial design are discussed.

Nicosulfuron, a sulfonylurea herbicide, alters embryonic development and oxidative status of hatchlings at environmental concentrations in an amphibian species

The widespread use of agrochemicals for controlling pests and diseases of crops is recognized as a main threat to biodiversity. Sulfonylurea herbicides are being increasingly used and display low levels of degradation in water which suggest that they might affect non-target organisms. In a common garden experiment, eggs of a widespread amphibian (Bufo spinosus) were exposed to sublethal environmentally relevant concentrations of a widely used sulfonylurea herbicide, nicosulfuron, during the whole embryonic development. We assessed development-related traits (i.e., development duration, hatching success, hatchling size and occurrence of malformation) as well as antioxidant markers in response to contamination (i.e., SOD, GPx, catalase, thiols and relevant ratios thereof). We found that sublethal concentrations of nicosulfuron increased embryonic development duration, increased hatchling size and tended to increase malformations. Embryos exposed to nicosulfuron displayed decreased thiols and increased catalase activity suggesting alteration of oxidative status. We did not find any effect of nicosulfuron on SOD and GPx levels. Interestingly, higher catalase activity was linked to higher proportion of malformed individuals, suggesting that exposure to nicosulfuron induced teratogenic effects. Our results suggest that alteration of antioxidant levels might be one physiological mechanism through which nicosulfuron might cause detrimental effects on amphibian embryos. Sublethal effects of pesticides at environmentally relevant concentrations have been overlooked and require further investigations, especially in non-target taxa occurring in agricultural landscapes.

Aminomethylphosphonic acid (AMPA) alters oxidative status during embryonic development in an amphibian species

Glyphosate's primary metabolite (aminomethylphosphonic acid, AMPA) is known to alter embryonic development at environmentally relevant concentrations in amphibians. However, we have limited understanding of the physiological mechanisms through which AMPA affects organisms. In this study, we tested whether alteration of the oxidative status is one mechanism through which AMPA affects organism performance. To this end, we analysed several oxidative status markers in hatchling tadpoles that were exposed to sublethal concentrations of AMPA during embryonic development (~16 days). We compared the influence of environmentally relevant concentrations of AMPA (from 0.07 to 3.57 μg l^-1) on the relation between developmental traits (i.e, embryonic development duration, embryonic mortality and hatchling size) and oxidative status markers known to alter homeostasis when unbalanced (superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), thiols and ratios thereof). We included measures of telomere length as an indicator of physiological state. We found that AMPA concentrations induce non-monotonic effects on some oxidative status markers with hatchlings displaying elevated antioxidant responses (elevated thiols and unbalanced SOD/(GPx + CAT) ratio). The lack of effect of AMPA on the relation between developmental traits, oxidative status and telomere length suggests that selective mortality of embryos susceptible to oxidative stress may have occurred prior to hatching in individuals less resistant to AMPA which display lower hatching success. Future studies are required to disentangle whether oxidative unbalance is a cause or a consequence of AMPA exposition. This study highlights the need to investigate effects of the metabolites of contaminants at environmental concentrations to comprehensively assess impacts of anthropogenic contamination on wildlife.

Biogeographic history moulds population differentiation in ageing of oxidative status in an amphibian

Regulation of oxidative status plays a substantial role in physiological ageing. However, we know little about age-related changes of oxidative status in wild animals, and even less about the role of population history in moulding ageing rates. We addressed these questions by means of a common garden experiment, using the Tyrrhenian tree frog Hyla sarda as the study species. This species underwent a range expansion from northern Sardinia (source) up to Corsica (newly founded) during the Late Pleistocene, and then the two populations became geographically isolated. We found that, at the beginning of the experiment, Sardinian and Corsican frogs had similar concentrations of all oxidative status markers analysed. One year later, Corsican frogs had higher oxidative stress and suffered higher mortality than Sardinian frogs. Our results suggest the intriguing scenario that population differentiation in rates of physiological ageing owing to oxidative stress might be an overlooked legacy of past biogeographic processes.

Association of superoxide dismutase enzyme with staging and grade of differentiation colorectal cancer: A cross-sectional study

Introduction

The increase of superoxide dismutase (SOD) level in colorectal cancer (CRC) patients based on the examination of staging and grade of differentiation still evidently represents a clinical problem. SOD level raises at a certain staging and reduce at a certain grade of differentiation. For that reason, this study aimed to assess the association between SOD and the variables analyzed in this study.

Materials and methods

This study was observational study using a cross-sectional research design aimed to measure the association between SOD and staging as well as grade of differentiation in CRC incidence. The study was conducted in our institution from January until March 2018.

Results

Statistical analyses of the data derived from the laboratory indicated that age and histopathological examination (TNM staging) had statistically significant correlation with SOD1 level. This significant correlation was proven from results of the statistical analyses of each variable at p = 0.039 (age) and p = 0.001 (TNM staging) respectively. Subsequent tests concerning the correlation between age and TNM staging on SOD1 level revealed that the study samples in the category of 30-49 age years old showed statistically significant correlation with SOD1 level with p = 0.009.

Conclusion

The increase of grade of differentiation was proportional to the increase of SOD1 level as antioxidant against cancer in CRC patients.

Antioxidants in Down Syndrome: From Preclinical Studies to Clinical Trials

There is currently no effective pharmacological therapy to improve the cognitive dysfunction of individuals with Down syndrome (DS). Due to the overexpression of several chromosome 21 genes, cellular and systemic oxidative stress (OS) is one of the most important neuropathological processes that contributes to the cognitive deficits and multiple neuronal alterations in DS. In this condition, OS is an early event that negatively affects brain development, which is also aggravated in later life stages, contributing to neurodegeneration, accelerated aging, and the development of Alzheimer's disease neuropathology. Thus, therapeutic interventions that reduce OS have been proposed as a promising strategy to avoid neurodegeneration and to improve cognition in DS patients. Several antioxidant molecules have been proven to be effective in preclinical studies; however, clinical trials have failed to show evidence of the efficacy of different antioxidants to improve cognitive deficits in individuals with DS. In this review we summarize preclinical studies of cell cultures and mouse models, as well as clinical studies in which the effect of therapies which reduce oxidative stress and mitochondrial alterations on the cognitive dysfunction associated with DS have been assessed.

[Relationship between central obesity and oxidative stress in premenopausal versus postmenopausal women]

Introduction

Background: endocrine changes in midlife women produce an increase in central obesity and oxidative stress, thus it is possible that obese postmenopausal women exhibit a higher oxidative stress than premenopausal women. Objective: to evaluate the relationship between central obesity and oxidative stress in premenopausal compared with postmenopausal women using different indices. Methods: this is a cross-sectional study that included 237 pre- and 255 post-menopausal women (40-60 years old). As oxidative stress markers we measured plasma malondialdehyde and serum uric acid levels, erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GPx), and total plasma antioxidant status. We also measured height, weight, and waist and hip circumferences, and we calculated body mass index (BMI), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR). Results: we found over 30% of women within the obesity range, whereas 50% were placed in the overweight category in both groups. Plasma malondialdehyde and serum uric acid levels were higher in women with overweight or obesity than in women with normal weight regardless of menopausal status. We found a positive correlation between WHtR and malondialdehyde level (r = 0.298, p < 0.0001) and serum uric acid level (r = 0.263, p < 0.0001), and a negative correlation with erythrocyte GPx activity (r = -0.148, p < 0.01). If we use a WHtR > 0.6, malondialdehyde and uric acid levels increase regardless of menopausal status. The other indices measured did not show any relationship. Conclusion: our findings suggest that there is an association between central obesity, as measured with WHtR, and increased oxidative stress regardless of menopausal status.

Cellular Senescence in Neurodegenerative Diseases

Cellular senescence is a homeostatic biological process characterized by a permanent state of cell cycle arrest that can contribute to the decline of the regenerative potential and function of tissues. The increased presence of senescent cells in different neurodegenerative diseases suggests the contribution of senescence in the pathophysiology of these disorders. Although several factors can induce senescence, DNA damage, oxidative stress, neuroinflammation, and altered proteostasis have been shown to play a role in its onset. Oxidative stress contributes to accelerated aging and cognitive dysfunction stages affecting neurogenesis, neuronal differentiation, connectivity, and survival. During later life stages, it is implicated in the progression of cognitive decline, synapse loss, and neuronal degeneration. Also, neuroinflammation exacerbates oxidative stress, synaptic dysfunction, and neuronal death through the harmful effects of pro-inflammatory cytokines on cell proliferation and maturation. Both oxidative stress and neuroinflammation can induce DNA damage and alterations in DNA repair that, in turn, can exacerbate them. Another important feature associated with senescence is altered proteostasis. Because of the disruption in the function and balance of the proteome, senescence can modify the proper synthesis, folding, quality control, and degradation rate of proteins producing, in some diseases, misfolded proteins or aggregation of abnormal proteins. There is an extensive body of literature that associates cellular senescence with several neurodegenerative disorders including Alzheimer’s disease (AD), Down syndrome (DS), and Parkinson’s disease (PD). This review summarizes the evidence of the shared neuropathological events in these neurodegenerative diseases and the implication of cellular senescence in their onset or aggravation. Understanding the role that cellular senescence plays in them could help to develop new therapeutic strategies.

Association between hot flashes severity and oxidative stress among Mexican postmenopausal women: A cross-sectional study

Objective

To assess the association between hot flashes (HFs) severity and oxidative stress (OS) in Mexican postmenopausal women.

Methods

A cross-sectional study was carried out with perimenopausal women aged 40–59 years community-dwelling from Mexico City, Mexico. They participated in Menopause and Oxidative Stress Project. The baseline sample consisted of 476 women recruited to participate; 161 women were excluded due to different reasons. Hence, 315 women were selected to establish two groups, a) 145 premenopausal women (yet with menstrual bleeding), and b) 170 postmenopausal women (without menses). All women were free of cardiovascular, kidney, hepatic or cancer disease, and without antioxidant supplement intake for at least six months prior to the beginning of the study; none had previously received hormone therapy. As OS markers, we measured plasma malondialdehyde using the TBARS assay, erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GPx), uric acid, and total antioxidant status; also, we calculated SOD/GPx ratio, antioxidant gap and an oxidative stress score ranging from 0 to 7. The HFs were evaluated using the Menopause Rating Scale. The women completed Spanish version of the Athens Insomnia Scale, Zung Self-Rating Anxiety Scale and Zung Self-Rating Depression Scale and a questionnaire of pro-oxidant factors.

Results

Stress score increased with HFs severity (mild 2.7±0.17, moderate 2.9±0.20 and severe 3.7±0.20, p = 0.001) in postmenopausal women. We observed a positive correlation between HFs severity and stress score, r = 0.247 (p = 0.001) in postmenopausal women; other test scores were not correlated. Severe HFs were a risk factor for OS (OR = 5.12, 95%CI: 1.99–13.17, p<0.05) in an adjusted multivariate analysis by different postmenopausal symptoms and pro-oxidant factors; we did not see any association in premenopausal women.

Conclusion

Our findings suggest an association between HFs severity and OS in Mexican postmenopausal women.

Putative Effects of Nutritive Polyphenols on Bone Metabolism In Vivo-Evidence from Human Studies

For the prevention and treatment of bone loss related diseases, focus has been put on naturally derived substances such as polyphenols. Based on human intervention studies, this review gives an overview of the effects of dietary significant polyphenols (flavonoids, hydroxycinnamic acids, and stilbenes) on bone turnover. Literature research was conducted using PubMed database and articles published between 01/01/2008 and 31/12/2018 were included (last entry: 19/02/2019). Randomized controlled trials using oral polyphenol supplementation, either of isolated polyphenols or polyphenols-rich foods with healthy subjects or study populations with bone disorders were enclosed. Twenty articles fulfilled the inclusion criteria and the average study quality (mean Jadad score: 4.5) was above the pre-defined cut-off of 3.0. Evidence from these studies does not allow an explicit conclusion regarding the effects of dietary important polyphenols on bone mineral density and bone turnover markers. Differences in study population, habitual diet, lifestyle factors, applied polyphenols, used doses, and polyphenol bioavailability complicate the comparison of study outcomes.

Toxicokinetic and toxicodynamic (TK-TD) modeling to study oxidative stress-dependent toxicity of heavy metals in zebrafish

Adverse outcome pathways (AOP) have been proposed as a new method to improve the ecological risk assessment of pollutants, but it requires quantitation linkage between exposure, biomarker response and toxicity of pollutants. A toxicokinetic and toxicodynamic (TK-TD) model was used to quantify AOP of the toxicity of Cd and Pb to zebrafish, including the quantitative relationship between Cd and Pb accumulation in gill and oxidative damage level based on ROS or MDA, and LC₅₀ values at different times. Significant relationships were found between the oxidative damage level characterized by ROS and MDA content and Cd or Pb accumulation in gill (R² > 0.60), and the TK model could better simulate the Pb accumulation in the gills (R² > 0.60) than Cd. The increasing of Cd or Pb concentrations induced the generation of ROS and the formation of ROS initiated the fluctuation of MDA level in the cells as compared to controls (p < 0.05). For the individual level effect, the Damage Assessment Model (DAM) could successfully explain the change of LC_50-ROS and LC_50-MDA values at different times (R² > 0.99). Our findings suggested that the TK-TD model based on ROS and MDA could be used as a quantitative AOP to predict toxicity of metals to zebrafish.

Mitochondrial Oxidative Stress and Antioxidants Balance in Fatty Liver Disease

Fatty liver disease is one of the most prevalent forms of chronic liver disease that encompasses both alcoholic liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD). Alcoholic steatohepatitis (ASH) and nonalcoholic steatohepatitis (NASH) are intermediate stages of ALD and NAFLD, which can progress to more advanced forms, including cirrhosis and hepatocellular carcinoma. Oxidative stress and particularly alterations in mitochondrial function are thought to play a significant role in both ASH and NASH and recognized to contribute to the generation of reactive oxygen species (ROS), as documented in experimental models. Despite the evidence of ROS generation, the therapeutic efficacy of treatment with antioxidants in patients with fatty liver disease has yielded poor results. Although oxidative stress is considered to be the disequilibrium between ROS and antioxidants, there is evidence that a subtle balance among antioxidants, particularly in mitochondria, is necessary to avoid the generation of ROS and hence oxidative stress. Conclusion: As mitochondria are a major source of ROS, the present review summarizes the role of mitochondrial oxidative stress in ASH and NASH and presents emerging data indicating the need to preserve mitochondrial antioxidant balance as a potential approach for the treatment of human fatty liver disease, which may pave the way for the design of future trials to test the therapeutic role of antioxidants in fatty liver disease.

Cockayne Syndrome Type A Protein Protects Primary Human Keratinocytes from Senescence

Defects in Cockayne syndrome type A (CSA), a gene involved in nucleotide excision repair, cause an autosomal recessive syndrome characterized by growth failure, progressive neurological dysfunction, premature aging, and skin photosensitivity and atrophy. Beyond its role in DNA repair, the CSA protein has additional functions in transcription and oxidative stress response, which are not yet fully elucidated. Here, we investigated the role of CSA protein in primary human keratinocyte senescence. Primary keratinocytes from three patients with CS-A displayed premature aging features, namely premature clonal conversion, high steady-state levels of reactive oxygen species and 8-OH-hydroxyguanine, and senescence-associated secretory phenotype. Stable transduction of CS-A keratinocytes with the wild-type CSA gene restored the normal cellular sensitivity to UV irradiation and normal 8-OH-hydroxyguanine levels. Gene correction was also characterized by proper restoration of keratinocyte clonogenic capacity and expression of clonal conversion key regulators (p16 and p63), decreased NF-κB activity and, in turn, the expression of its targets (NOX1 and MnSOD), and the secretion of senescence-associated secretory phenotype mediators. Overall, the CSA protein plays an important role in protecting cells from senescence by facilitating DNA damage processing, maintaining physiological redox status and keratinocyte clonogenic ability, and reducing the senescence-associated secretory phenotype-mediated inflammatory phenotype.

Relationship Between Aerobic Capacity With Oxidative Stress and Inflammation Biomarkers in the Blood of Older Mexican Urban-Dwelling Population

The maximal oxygen uptake (VO2max) constitutes an indicator of an organism’s capacity to integrate oxygen into the metabolism to obtaining energy. The aim of this study was to determine the relationship between VO2max and oxidative stress (OxS) and chronic inflammation in the elderly individuals. A cross-sectional and exploratory study was conducted in a sample of 52 older persons. We measured plasma lipid peroxides (LPO), red blood cell glutathione peroxidase, red blood cell superoxide dismutase, and total antioxidant status. The interleukin 10 and tumor necrosis factor-α (TNF-α) were measured in serum by ELISA. The VO2max was determined by the Rockport aerobic test, and the energy expenditure (caloric expenditure and metabolic equivalence unit (MET) per day) was measured by a 3-day activity record. We observed a positive correlation between VO2 max with IL-10, MET/day•day-1 and kcal•day-1 (r = 0.31, P < .05, r = 0.44, P < .01, and r = 0.29, P < .05, respectively), and a negative correlation with the body mass index, TNF-α, and LPO (r = −0.27, P < .05, r = −0.29, P < .05, and r = −0.40, P < .01 respectively). Our findings suggest that there is an inverse relationship between the aerobic capacity and the OxS and chronic inflammation biomarkers in the blood in older Mexican adults.

Oxidative Stress and Apoptosis in Benzo[a]pyrene-Induced Neural Tube Defects

Neural tube defects (NTDs) are among the most common and severe congenital malformations and result from incomplete closure of the neural tube during early development. Maternal exposure to polycyclic aromatic hydrocarbons (PAHs) has been suggested to be a risk factor for NTDs and previous studies imply that the mechanism underlying the association between PAH exposure and NTDs may involve oxidative stress and apoptosis. The objectives of this study were to investigate whether there is a direct effect of maternal benzo[α] pyrene (BaP) exposure on the closure of the neural tube in mice, and to examine the underlying mechanisms by combining animal experiments and human subject studies. We found that intraperitoneal injection of BaP from embryonic day 7 at a dose of 250 mg kg^-1 induced NTDs (13.3% frequency) in ICR mice. BaP exposure significantly increased expression of genes associated with oxidative stress, Cyp1a1, Sod1 and Sod2, while repressing Gpx1. Elevated apoptosis and higher protein expression of cleaved caspase-3 in the neuroepithelium of treated embryos were observed. Pre-treatment with vitamin E, added to food, significantly protected against BaP-induced NTDs (1.4% frequency) (P < 0.05). Vitamin E also partly normalized oxidative stress related gene expression and excess apoptosis in BaP-treated embryos. Examination of human neural tissues revealed that increased levels of protein carbonyl and apoptosis were related with maternal exposure to PAHs and the risk of NTDs. Collectively, these results suggest that BaP exposure could induce NTDs and that this may involve increased oxidative stress and apoptosis, while vitamin E may have a protective effect.

What effect does regular exercise have on oxidative stress in people with Down syndrome? A systematic review with meta-analyses

OBJECTIVE

What effect does regular exercise have on oxidative stress in people with Down syndrome?

DESIGN

Systematic review with meta-analyses.

METHODS

A systematic review with meta-analyses was conducted. Six databases were searched from inception until August 2017. Studies where included if participants with Down syndrome (any age) had completed an exercise program of at least 6 weeks duration and at least one biomarker measured the generation or removal of reactive oxidative species. Data were extracted using a customised form. Risk of bias was assessed using the Cochrane Collaboration's Risk of Bias assessment tool. Effect sizes were calculated and meta-analyses completed for clinically homogeneous data using a random effects model.

RESULTS

Seven studies (11 articles) involving 144 inactive participants investigated the effect of moderate intensity aerobic exercise. No pattern emerged for how most biomarkers responded with non-significant pooled effect sizes and high levels of heterogeneity observed. The exception was catalase which increased significantly after exercise (standardised mean difference 0.39, 95%CI 0.04-0.75; I² 15%). Available studies were at high risk of bias. Two of five studies that measured more than one biomarker reported a decrease in oxidative stress with increased antioxidant activity after exercise but the other three (including one small randomised controlled trial) reported increased oxidative stress with variable change in antioxidant activity.

CONCLUSIONS

There remains uncertainty about the effect of exercise on oxidative stress in people with Down syndrome.

REVIEW REGISTRATION

PROSPERO CRD42016048492.

Chemotherapy-Induced Tissue Injury: An Insight into the Role of Extracellular Vesicles-Mediated Oxidative Stress Responses

The short- and long-term side effects of chemotherapy limit the maximum therapeutic dose and impair quality of life of survivors. Injury to normal tissues, especially chemotherapy-induced cardiomyopathy, is an unintended outcome that presents devastating health impacts. Approximately half of the drugs approved by the Food and Drug Administration for cancer treatment are associated with the generation of reactive oxygen species, and Doxorubicin (Dox) is one of them. Dox undergoes redox cycling by involving its quinone structure in the production of superoxide free radicals, which are thought to be instrumental to the role it plays in cardiomyopathy. Dox-induced protein oxidation changes protein function, translocation, and aggregation that are toxic to cells. To maintain cellular homeostasis, oxidized proteins can be degraded intracellularly by ubiquitin-proteasome pathway or by autophagy, depending on the redox status of the cell. Alternatively, the cell can remove oxidized proteins by releasing extracellular vesicles (EVs), which can be transferred to neighboring or distant cells, thereby instigating an intercellular oxidative stress response. In this article, we discuss the role of EVs in oxidative stress response, the potential of EVs as sensitive biomarkers of oxidative stress, and the role of superoxide dismutase in attenuating EV-associated oxidative stress response resulting from chemotherapy.

Intravenous superoxide dismutase as a protective agent to prevent impairment of lung function induced by high tidal volume ventilation

Background

Positive-pressure mechanical ventilation is essential in assisting patients with respiratory failure in the intensive care unit and facilitating oxygenation in the operating room. However, it was also recognized as a primary factor leading to hospital-acquired pulmonary dysfunction, in which pulmonary oxidative stress and lung inflammation had been known to play important roles. Cu/Zn superoxide dismutase (SOD) is an important antioxidant, and possesses anti-inflammatory capacity. In this study, we aimed to study the efficacy of Cu/Zn SOD, administered intravenously during high tidal volume (HTV) ventilation, to prevent impairment of lung function.

Methods

Thirty-eight male Sprague-Dawley rats were divided into 3 groups: 5 h ventilation with (A) low tidal volume (LTV; 8 mL/kg; n = 10), (B) high tidal volume (HTV; 18 mL/kg; n = 14), or (C) HTV and intravenous treatment of Cu/Zn SOD at a dose of 1000 U/kg/h (HTV + SOD; n = 14). Lung function was evaluated both at baseline and after 5-h ventilation. Lung injury was assessed by histological examination, lung water and protein contents in the bronchoalveolar lavage fluid (BALF). Pulmonary oxidative stress was examined by concentrations of methylguanidine (MG) and malondialdehyde (MDA) in BALF, and antioxidative activity by protein expression of glutathione peroxidase-1 (GPx-1) in the lung. Severity of lung inflammation was evaluated by white blood cell and differential count in BALF, and protein expression of inducible nitric oxide synthase (iNOS), intercellular adhesion molecule-1 (ICAM-1), tumor necrosis factor-α (TNF-α), matrix metalloproteinase-9 (MMP-9), and mRNA expression of nuclear factor-κB (NF-κB) in the lung. We also examined protein expression of surfactant protein (SP)-A and D and we measured hourly changes in serum nitric oxide (NO) level.

Results

Five hours of LTV ventilation did not induce a major change in lung function, whereas 5 h of HTV ventilation induced apparent combined restrictive and obstructive lung disorder, together with increased pulmonary oxidative stress, decreased anti-oxidative activity and increased lung inflammation (P < 0.05). HTV ventilation also decreased SP-A and SP-D expression and suppressed serum NO level during the time course of ventilation. Cu/Zn SOD administered intravenously during HTV ventilation effectively reversed associated pulmonary oxidative stress and lung inflammation (P < 0.05); moreover, it preserved SP-A and SP-D expressions in the lung and increased serum nitric oxide (NO) level, enhancing vascular NO bioavailability.

Conclusions

HTV ventilation can induce combined restrictive and obstructive lung disorders. Intravenous administration of Cu/Zn SOD during HTV ventilation can prevent lung function impairment and lung injury via reducing pulmonary oxidative stress and lung inflammation, preserving pulmonary surfactant expression, and enhancing vascular NO bioavailability.

Effects of astaxanthin on oxidative stress induced by Cu2+ in prostate cells

Astaxanthin (AST), a carotenoid molecule extensively found in marine organisms and increasingly used as a dietary supplement, has been reported to have beneficial effects against oxidative stress. In the current paper, the effects of AST on viability of prostate cells were investigated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay; cell apoptosis and intracellular reactive oxygen species (ROS) levels were determined by flow cytometry; the mitochondrial membrane potential (MMP) was measured by fluorospectrophotometer; and activities of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) were evaluated by a detection kit. The results show that copper ion (Cu²⁺) induced apoptosis, along with the accumulation of intracellular ROS and MDA, in both prostate cell lines (RWPE-1 and PC-3). AST treatments could decrease the MDA levels, increase MMP, and keep ROS stable in RWPE-1 cell line. An addition of AST decreased the SOD, GSH-Px, and CAT activities in PC-3 cell line treated with Cu²⁺, but had a contrary reaction in RWPE-1 cell lines. In conclusion, AST could contribute to protecting RWPE-1 cells against Cu²⁺-induced injuries but could cause damage to the antioxidant enzyme system in PC-3 cells.

What people with Down Syndrome can teach us about cardiopulmonary disease

Down syndrome is the most common chromosomal abnormality among live-born infants. Through full or partial trisomy of chromosome 21, Down syndrome is associated with cognitive impairment, congenital malformations (particularly cardiovascular) and dysmorphic features. Immune disturbances in Down syndrome account for an enormous disease burden ranging from quality-of-life issues (autoimmune alopecia) to more serious health issues (autoimmune thyroiditis) and life-threatening issues (leukaemia, respiratory tract infections and pulmonary hypertension). Cardiovascular and pulmonary diseases account for ∼75% of the mortality seen in persons with Down syndrome. This review summarises the cardiovascular, respiratory and immune challenges faced by individuals with Down syndrome, and the genetic underpinnings of their pathobiology. We strongly advocate increased comparative studies of cardiopulmonary disease in persons with and without Down syndrome, as we believe these will lead to new strategies to prevent and treat diseases affecting millions of people worldwide.

Synthetic combinations of missense polymorphic genetic changes underlying Down syndrome susceptibility

Single nucleotide polymorphisms (SNPs) are important biomolecular markers in health and disease. Down syndrome, or Trisomy 21, is the most frequently occurring chromosomal abnormality in live-born children. Here, we highlight associations between SNPs in several important enzymes involved in the one-carbon folate metabolic pathway and the elevated maternal risk of having a child with Down syndrome. Our survey highlights that the combination of SNPs may be a more reliable predictor of the Down syndrome phenotype than single SNPs alone. We also describe recent links between SNPs in p53 and its related pathway proteins and Down syndrome, as well as highlight several proteins that help to associate apoptosis and p53 signaling with the Down syndrome phenotype. In addition to a comprehensive review of the literature, we also demonstrate that several SNPs reside within the same regions as these Down syndrome-linked SNPs, and propose that these closely located nucleotide changes may provide new candidates for future exploration.

The contribution of the citrate pathway to oxidative stress in Down syndrome

Inflammatory conditions and oxidative stress have a crucial role in Down syndrome (DS). Emerging studies have also reported an altered lipid profile in the early stages of DS. Our previous works demonstrate that citrate pathway activation is required for oxygen radical production during inflammation. Here, we find up-regulation of the citrate pathway and down-regulation of carnitine/acylcarnitine carrier and carnitine palmitoyl-transferase 1 genes in cells from children with DS. Interestingly, when the citrate pathway is inhibited, we observe a reduction in oxygen radicals as well as in lipid peroxidation levels. Our preliminary findings provide evidence for a citrate pathway dysregulation, which could be related to some phenotypic traits of people with DS.

Early redox imbalance is associated with liver dysfunction at weaning in overfed rats

Neonatal overfeeding induced by litter size reduction leads to further obesity and other metabolic disorders, such as liver oxidative stress and microsteatosis at adulthood. We hypothesized that overfeeding causes an early redox imbalance at weaning, which could programme the animals to future liver dysfunction. Thus, we studied lipogenesis, adipogenesis, catecholamine status and oxidative balance in weaned overfed pups. To induce early overfeeding, litters were adjusted to three pups at the 3rd day of lactation (SL group). The control group contained 10 pups per litter until weaning (NL group). Peripheral autonomic nerve function was determined in vivo at 21 days old. Thereafter, pups were killed for further analysis. Differences were considered significant when P < 0.05. The SL pups presented with a higher visceral adipocyte area, higher content of lipogenic enzymes (ACC, FAS) and with a lower content of adipogenic factors (CEBP, PPARγ) in visceral adipose tissue (VAT). Although autonomic nerve activity and adrenal catecholamine production were not significantly altered, catecholamine receptor (β3ADR) content was lower in VAT. The SL pups also presented with higher triglyceride, PPARγ, PPARα and PGC1α contents in liver. In plasma and liver, the SL pups showed an oxidative imbalance, with higher lipid peroxidation and protein oxidation. The SL group presented with a higher serum alanine aminotransferase (ALT). The early increase in lipogenesis in adipose tissue and liver in weaned overfed rats suggests that the higher oxidative stress and lower catecholamine content in VAT are associated with the early development of liver dysfunction and adipocyte hypertrophy.

Reproduction Does Not Adversely Affect Liver Mitochondrial Respiratory Function but Results in Lipid Peroxidation and Increased Antioxidants in House Mice

Reproduction is thought to come at a cost to longevity. Based on the assumption that increased energy expenditure during reproduction is associated with increased free-radical production by mitochondria, oxidative damage has been suggested to drive this trade-off. We examined the impact of reproduction on liver mitochondrial function by utilizing post-reproductive and non-reproductive house mice (Mus musculus) living under semi-natural conditions. The age-matched post-reproductive and non-reproductive groups were compared after the reproductive females returned to a non-reproductive state, so that both groups were in the same physiological state at the time the liver was collected. Despite increased oxidative damage (p = 0.05) and elevated CuZnSOD (p = 0.002) and catalase (p = 0.04) protein levels, reproduction had no negative impacts on the respiratory function of liver mitochondria. Specifically, in a post-reproductive, maintenance state the mitochondrial coupling (i.e., respiratory control ratio) of mouse livers show no negative impacts of reproduction. In fact, there was a trend (p = 0.059) to suggest increased maximal oxygen consumption by liver mitochondria during the ADP stimulated state (i.e., state 3) in post-reproduction. These findings suggest that oxidative damage may not impair mitochondrial respiratory function and question the role of mitochondria in the trade-off between reproduction and longevity. In addition, the findings highlight the importance of quantifying the respiratory function of mitochondria in addition to measuring oxidative damage.

Paradoxical Roles of Antioxidant Enzymes: Basic Mechanisms and Health Implications

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are generated from aerobic metabolism, as a result of accidental electron leakage as well as regulated enzymatic processes. Because ROS/RNS can induce oxidative injury and act in redox signaling, enzymes metabolizing them will inherently promote either health or disease, depending on the physiological context. It is thus misleading to consider conventionally called antioxidant enzymes to be largely, if not exclusively, health protective. Because such a notion is nonetheless common, we herein attempt to rationalize why this simplistic view should be avoided. First we give an updated summary of physiological phenotypes triggered in mouse models of overexpression or knockout of major antioxidant enzymes. Subsequently, we focus on a series of striking cases that demonstrate "paradoxical" outcomes, i.e., increased fitness upon deletion of antioxidant enzymes or disease triggered by their overexpression. We elaborate mechanisms by which these phenotypes are mediated via chemical, biological, and metabolic interactions of the antioxidant enzymes with their substrates, downstream events, and cellular context. Furthermore, we propose that novel treatments of antioxidant enzyme-related human diseases may be enabled by deliberate targeting of dual roles of the pertaining enzymes. We also discuss the potential of "antioxidant" nutrients and phytochemicals, via regulating the expression or function of antioxidant enzymes, in preventing, treating, or aggravating chronic diseases. We conclude that "paradoxical" roles of antioxidant enzymes in physiology, health, and disease derive from sophisticated molecular mechanisms of redox biology and metabolic homeostasis. Simply viewing antioxidant enzymes as always being beneficial is not only conceptually misleading but also clinically hazardous if such notions underpin medical treatment protocols based on modulation of redox pathways.

Superoxide dismutase activity and gene expression levels in Saudi women with recurrent miscarriage

The antioxidant activities of superoxide dismutase 1 (SOD1) and SOD2, as well as the levels of the oxidant superoxide anion (SOA) and the micronutrients zinc (Zn), copper (Cu) and manganese (Mn), were assayed in plasma, whole blood and placental tissue of non-pregnant (NP), healthy pregnant (HP) women and recurrent miscarriage (RM) patients. The results showed that SOD1 and SOD2 activities and the levels of Zn, Cu and Mn in plasma and whole blood of HP women were slightly, but significantly lower, and even more significantly decreased in RM patients compared to those observed in NP women (P<0.05 and P<0.0001, respectively). Additionally, whereas plasma SOD1 and SOD2 activities and Zn, Cu and Mn levels were significantly lower in RM patients, those of whole blood and placental tissue were significantly lower when compared to HP women (P<0.001 and P<0.0001, respectively). Concurrently, there were consistent increases of equal magnitude and statistical significance in SOA levels in all the assayed samples as identified by a comparison between the subjects. The findings thus supported oxidative metabolism and excessive reactive oxygen species generation. The resultant oxidative stress, identified in whole blood and placental tissues of RM patients, may have been a primary cause of RM. Dietary supplementation of Zn, Cu and Mn may be beneficial to these patients pre- and post-conception.

Catalytic role of iron-superoxide dismutase in hydrogen abstraction by super oxide radical anion from ascorbic acid

The catalytic role of iron-superoxide dismutase (Fe-SOD) in the working of ascorbic acid (AA) as a superoxide radical anion scavenger has been studied by employing a model developed recently for the active site of the enzyme.

Organ and tissue-dependent effect of resveratrol and exercise on antioxidant defenses of old mice

BACKGROUND

Oxidative stress has been considered one of the causes of aging. For this reason, treatments based on antioxidants or those capable of increasing endogenous antioxidant activity have been taken into consideration to delay aging or age-related disease progression.

AIM

In this paper, we determine if resveratrol and exercise have similar effect on the antioxidant capacity of different organs in old mice.

METHODS

Resveratrol (6 months) and/or exercise (1.5 months) was administered to old mice. Markers of oxidative stress (lipid peroxidation and glutathione) and activities and levels of antioxidant enzymes (SOD, catalase, glutathione peroxidase, glutathione reductase and transferase and thioredoxin reductases, NADH cytochrome B5-reductase and NAD(P)H-quinone acceptor oxidoreductase) were determined by spectrophotometry and Western blotting in different organs: liver, kidney, skeletal muscle, heart and brain.

RESULTS

Both interventions improved antioxidant activity in the major organs of the mice. This induction was accompanied by a decrease in the level of lipid peroxidation in the liver, heart and muscle of mice. Both resveratrol and exercise modulated several antioxidant activities and protein levels. However, the effect of resveratrol, exercise or their combination was organ dependent, indicating that different organs respond in different ways to the same stimulus.

CONCLUSIONS

Our data suggest that physical activity and resveratrol may be of great importance for the prevention of age-related diseases, but that their organ-dependent effect must be taken into consideration to design a better intervention.

A genetic cause of Alzheimer disease: mechanistic insights from Down syndrome

Down syndrome, which arises in individuals carrying an extra copy of chromosome 21, is associated with a greatly increased risk of early-onset Alzheimer disease. It is thought that this risk is conferred by the presence of three copies of the gene encoding amyloid precursor protein (APP)--an Alzheimer disease risk factor--although the possession of extra copies of other chromosome 21 genes may also play a part. Further study of the mechanisms underlying the development of Alzheimer disease in people with Down syndrome could provide insights into the mechanisms that cause dementia in the general population.

Morus nigra leaf extract improves glycemic response and redox profile in the liver of diabetic rats

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by hyperglycemia and alterations in the carbohydrate, lipid, and protein metabolism. DM is associated with increased oxidative stress and pancreatic beta cell damage, which impair the production of insulin and the maintenance of normoglycemia. Inhibiting oxidative damage and controlling hyperglycemia are two important strategies for the prevention of diabetes. The pulp and leaf extracts of mulberry (Morus nigra L.) have abundant total phenolics and flavonoids, and its antioxidant potential may be an important factor for modulating oxidative stress induced by diabetes. In this study, DM was induced by intraperitoneal injection of alloxan monohydrate (135 mg kg(-1)). Female Fischer rats were divided into four groups: control, diabetic, diabetic pulp, and diabetic leaf extract. Animals in the diabetic pulp and diabetic leaf extract groups were treated for 30 days with M. nigra L. pulp or leaf extracts, respectively. At the end of treatment, animals were euthanized and, liver and blood samples were collected for analysis of biochemical and metabolic parameters. Our study demonstrated that treatment of diabetic rats with leaf extracts decreased the superoxide dismutase (SOD)/catalase (CAT) ratio and carbonylated protein levels by reducing oxidative stress. Moreover, the leaf extract of M. nigra L. decreased the matrix metalloproteinase (MMP)-2 activity, increased insulinemia, and alleviated hyperglycemia-induced diabetes. In conclusion, our study found that the leaf extract of M. nigra L. improved oxidative stress and complications in diabetic rats, suggesting the utility of this herbal remedy in the prevention and treatment of DM.

Intracellular oxidant activity, antioxidant enzyme defense system, and cell senescence in fibroblasts with trisomy 21

Down's syndrome (DS) is characterized by a complex phenotype associated with chronic oxidative stress and mitochondrial dysfunction. Overexpression of genes on chromosome-21 is thought to underlie the pathogenesis of the major phenotypic features of DS, such as premature aging. Using cultured fibroblasts with trisomy 21 (T21F), this study aimed to ascertain whether an imbalance exists in activities, mRNA, and protein expression of the antioxidant enzymes SOD1, SOD2, glutathione-peroxidase, and catalase during the cell replication process in vitro. T21F had high SOD1 expression and activity which led to an interenzymatic imbalance in the antioxidant defense system, accentuated with replicative senescence. Intracellular ROS production and oxidized protein levels were significantly higher in T21F compared with control cells; furthermore, a significant decline in intracellular ATP content was detected in T21F. Cell senescence was found to appear prematurely in DS cells as shown by SA-β-Gal assay and p21 assessment, though not apoptosis, as neither p53 nor the proapoptotic proteins cytochrome c and caspase 9 were altered in T21F. These novel findings would point to a deleterious role of oxidatively modified molecules in early cell senescence of T21F, thereby linking replicative and stress-induced senescence in cultured cells to premature aging in DS.

The association between oxidative stress and bone mineral density according to menopausal status of Korean women

Objective

The aim of this study is to investigate the association between oxidative stress and bone mineral density (BMD) according to menopausal status of Korean women.

Methods

A total of 2,232 women who visited to the health promotion center at Pusan National University Hospital between 2010 and 2014 were included in this cross-sectional study. Laboratory tests, such as uric acid, albumin, total bilirubin, which were evaluated as a natural antioxidants. Homocysteine also was evaluated as a factor associated with oxidative stress. Correlation analyses and partial correlation coefficient between BMD scores and laboratory parameters associated with oxidative stress according to menopausal status were performed with Pearson test.

Results

By correlation analysis, uric acid had only positive correlation with femur and lumbar BMD in premenopausal and postmenopausal group. But albumin and bilirubin, which were the other natural antioxidants, had no correlation with BMD except total bilirubin with femur BMD in postmenopausal group. Homocysteine had negative correlation with femur BMD in postmenopausal group. But there were different results in partial correlation coefficient adjusted by age and BMI. In premenopausal group, uric acid was still positive correlation with femur and lumbar BMD, whereas in postmenopausal group homocysteine had no correlation with femur BMD, total bilirubin and uric acid had no correlation with lumbar BMD. At the multiple logistic regressions, only age and menopause status, uric acid had correlation with BMD.

Conclusion

In this study, homocysteine had no correlation with BMD. But in natural antioxidant, uric acid had only positive correlation with BMD.

Protective effect of Baccharis trimera extract on acute hepatic injury in a model of inflammation induced by acetaminophen

BACKGROUND

Acetaminophen (APAP) is a commonly used analgesic and antipyretic. When administered in high doses, APAP is a clinical problem in the US and Europe, often resulting in severe liver injury and potentially acute liver failure. Studies have demonstrated that antioxidants and anti-inflammatory agents effectively protect against the acute hepatotoxicity induced by APAP overdose.

METHODS

The present study attempted to investigate the protective effect of B. trimera against APAP-induced hepatic damage in rats. The liver-function markers ALT and AST, biomarkers of oxidative stress, antioxidant parameters, and histopathological changes were examined.

RESULTS

The pretreatment with B. trimera attenuated serum activities of ALT and AST that were enhanced by administration of APAP. Furthermore, pretreatment with the extract decreases the activity of the enzyme SOD and increases the activity of catalase and the concentration of total glutathione. Histopathological analysis confirmed the alleviation of liver damage and reduced lesions caused by APAP.

CONCLUSIONS

The hepatoprotective action of B. trimera extract may rely on its effect on reducing the oxidative stress caused by APAP-induced hepatic damage in a rat model. General Significance. These results make the extract of B. trimera a potential candidate drug capable of protecting the liver against damage caused by APAP overdose.

Antihyperglycemic, hypolipidemic, hepatoprotective and antioxidative effects of dietary clove (Szyzgium aromaticum) bud powder in a high-fat diet/streptozotocin-induced diabetes rat model

BACKGROUND

Syzygium aromaticum (L.) Merr. & Perry (clove) bud is an important spice used in the preparation of several delicacies and in folklore for diabetes management. The present study was convened to assess the effects of dietary clove bud powder (CBP) on biochemical parameters in a type 2 diabetes rat model, induced by a combination of high-fat diet and low-dose streptozotocin (35 mg kg⁻¹) for 30 days.

RESULTS

Diabetic rats were placed on dietary regimen containing 20-40 g kg⁻¹ clove bud powder. The results revealed that there was no significant (P > 0.05) difference in the average feed intake and weight changes between the rat groups. Furthermore, supplementation with CBP gradually reduced blood glucose level in diabetic rat compared to control diabetic rats without CBP supplementation (DBC). Moreover, reduced activity of α-glucosidase was observed in CBP and metformin-treated rat groups when compared to that of the DBC rat group. In addition, the DBC group had significantly (P < 0.05) higher lipid concentrations (except for high-density lipoprotein cholesterol) when compared to all other groups. Furthermore, CBP had significantly (P < 0.05) reduced activity of liver enzymes (alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase) and showed elevated levels of antioxidant status (glutathione, ascorbic acid, superoxide dismutase and catalase).

CONCLUSION

The results suggest that the clove bud diet may attenuate hyperglycemia, hyperlipidemia, hepatotoxicity and oxidative stress in the type 2 diabetic condition.

Impact of dietary oils and fats on lipid peroxidation in liver and blood of albino rats

OBJECTIVE

To investigate the effects of different dietary fat and oils (differing in their degree of saturation and unsaturation) on lipid peroxidation in liver and blood of rats.

METHODS

The study was conducted on 50 albino rats that were randomly divided into 5 groups of 10 animals. The groups were fed on dietary butter (Group I), margarine (Group II), olive oil (Group III), sunflower oil (Group IV) and corn oil (Group V) for 7 weeks. After 12 h of diet removal, livers were excised and blood was collected to measure malondialdehyde (MDA) levels in the supernatant of liver homogenate and in blood. Blood superoxide dismutase activity (SOD), glutathione peroxidase activity (GPx), serum vitamin E and total antioxidant capacity (TAC) levels were also measured to determine the effects of fats and oils on lipid peroxidation.

RESULTS

The results indicated that no significant differences were observed in SOD activity, vitamin E and TAC levels between the five groups. However, there was significant decrease of GPx activity in groups IV and V when compared with other groups. The results indicated that feeding corn oil caused significant increases in liver and blood MDA levels as compared with other oils and fats. There were positive correlations between SOD and GPx, vitamin E and TAC as well as between GPx and TAC (r: 0.743; P<0.001) and between blood MDA and liver MDA (r: 0.897; P<0.001). The results showed also negative correlations between blood MDA on one hand and SOD, GPx, vitamin E and TAC on the other hand.

CONCLUSIONS

The results demonstrated that feeding oils rich in polyunsaturated fatty acids (PUFA) increases lipid peroxidation significantly and may raise the susceptibility of tissues to free radical oxidative damage.

Intervention in cyclophosphamide induced oxidative stress and DNA damage by a flavonyl-thiazolidinedione based organoselenocyanate and evaluation of its efficacy during adjuvant therapy in tumor bearing mice

A novel flavonyl-thiazolidinedione based organoselenocyanate compound was synthesized and established as nontoxic at the doses of 2.5 and 5 mg/kg b.w. in mice. Oral administration of the compound in combination with cyclophosphamide (CP) resulted in an improved therapeutic efficacy which was mostly evidenced in terms of tumor burden and protection of normal cells. The adjuvant therapy was proved to be immensely significant in increasing the mean survivability of the tumor bearing hosts. Reduction in the tumor volume was manifested through the induction of apoptosis and generation of ROS in transformed cells. Moreover, the organoselenium compound could efficiently suppress CP-induced DNA damage, chromosomal aberration, hepatic damage and enhanced the activities of various antioxidant enzymes in normal cells.

Roundup disrupts male reproductive functions by triggering calcium-mediated cell death in rat testis and Sertoli cells

Glyphosate is the primary active constituent of the commercial pesticide Roundup. The present results show that acute Roundup exposure at low doses (36 ppm, 0.036 g/L) for 30 min induces oxidative stress and activates multiple stress-response pathways leading to Sertoli cell death in prepubertal rat testis. The pesticide increased intracellular Ca(2+) concentration by opening L-type voltage-dependent Ca(2+) channels as well as endoplasmic reticulum IP3 and ryanodine receptors, leading to Ca(2+) overload within the cells, which set off oxidative stress and necrotic cell death. Similarly, 30 min incubation of testis with glyphosate alone (36 ppm) also increased (45)Ca(2+) uptake. These events were prevented by the antioxidants Trolox and ascorbic acid. Activated protein kinase C, phosphatidylinositol 3-kinase, and the mitogen-activated protein kinases such as ERK1/2 and p38MAPK play a role in eliciting Ca(2+) influx and cell death. Roundup decreased the levels of reduced glutathione (GSH) and increased the amounts of thiobarbituric acid-reactive species (TBARS) and protein carbonyls. Also, exposure to glyphosate-Roundup stimulated the activity of glutathione peroxidase, glutathione reductase, glutathione S-transferase, γ-glutamyltransferase, catalase, superoxide dismutase, and glucose-6-phosphate dehydrogenase, supporting downregulated GSH levels. Glyphosate has been described as an endocrine disruptor affecting the male reproductive system; however, the molecular basis of its toxicity remains to be clarified. We propose that Roundup toxicity, implicated in Ca(2+) overload, cell signaling misregulation, stress response of the endoplasmic reticulum, and/or depleted antioxidant defenses, could contribute to Sertoli cell disruption in spermatogenesis that could have an impact on male fertility.