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Tick-borne encephalitis virus (TBEV) is the most important tick-transmitted arbovirus causing human disease in Europe, but information on its endemic occurrence varies between countries because of differences in surveillance systems. Objective data are necessary to ascertain the disease risk for vaccination recommendations and other public health interventions. In two independent, separately planned projects, we used real-time RT-PCR to detect TBE virus in questing ticks. In Poland, 32 sampling sites were selected in 10 administrative districts located in regions where sporadic TBE cases were reported. In Germany, 18 sampling sites were selected in two districts located in a region with high TBE incidence. Altogether, >16 000 ticks were tested by real-time RT-PCR, with no sample testing positive for TBEV. A systematic search for published studies on TBEV prevalence in ticks in Poland and Germany also suggested that testing large numbers of collected ticks could not consistently assure virus detection in known endemic foci. Although assignment of results to administrative regions is essential for TBE risk mapping, this was possible in only 10 (investigating 22 417 ticks) of 15 published studies (>50 000 ticks) identified. We conclude that the collection and screening of ticks by real-time RT-PCR cannot be recommended for assessment of human TBE risk. Alternative methods of environmental TBEV monitoring should be considered, such as serological monitoring of rodents or other wildlife. [ABSTRACT FROM AUTHOR]

Aims: The present study was performed to assess the effect of simultaneous long-term exposure to cadmium (Cd) and ethanol on iron (Fe) status of male Wistar rats. Methods: The animals received drinking water containing 50 mg of Cd/l and/or 10% (w/v) ethanol for 12 weeks. Fe and Cd concentrations in serum (blood), certain tissues, urine and feces were determined by atomic absorption spectrometry. The total pool of Fe was calculated as a sum of its content in liver, spleen, kidneys, heart and brain. Fe bioavailability was evaluated based on its apparent absorption. Results: The daily Cd intake ranged from 3.17 to 4.28 mg/kg (Cd group) and from 2.41 to 3.17 mg/kg (Cd + ethanol group); ethanol consumption ranged from 47.5 to 86.9 g/kg/24 h (ethanol group) and from 47.3 to 63.4 g/kg/24 h (Cd + ethanol group). Exposure to Cd or/and ethanol caused serious disturbances in Fe metabolism, as indicated by Fe body depletion. Both substances, applied alone and in combination, reduced the apparent Fe absorption and decreased its total pool in certain organs, and urinary excretion. However, the Cd- and ethanol-induced changes in the tissue Fe concentrations were different. Cd exposure decreased the concentration of Fe in serum, liver, spleen and femur, whereas ethanol decreased it in the spleen. In rats co-exposed to Cd and ethanol, decreased serum, spleen and brain Fe concentrations were all observed. Conclusions: The changes in Fe status in rats co-exposed to Cd and ethanol can be explained by the independent action of the two substances, leading to a decrease in Fe bioavailability, or by their interactions, which involves a modifying effect of ethanol on Cd turnover. The results allow the conclusion that ethanol may increase Cd accumulation, making the organism more susceptible to Fe depletion. Alcoholics thus may be at increased risk of disorders in Fe body status. [ABSTRACT FROM AUTHOR]

The present study was performed to assess the effect of short-term ethanol administration on cadmium retention and accumulation as well as on bioelement metabolism (zinc, copper, calcium, and magnesium) in rats exposed to an aqueous solution of cadmium chloride for 8 weeks. Intoxication with cadmium led to accumulation of this toxic metal, particularly in the liver and kidney, which was linked to metallothionein synthesis as well as to a disturbance in the metabolism of zinc, copper, and calcium. These effects were dependent on the level of exposure. The administration of ethanol in the final phase of cadmium treatment increased cadmium retention and accumulation in the body with simultaneous elevation in liver and kidney metallothionein concentration. Ethanol alone or with cadmium caused or intensified the cadmium-induced changes in metabolism of zinc and copper. Calcium metabolism disturbed by cadmium was not influenced by ethanol. Neither agents had any effect on magnesium metabolism. We conclude that even short-term ethanol consumption in conditions of exposure to cadmium can increase this heavy metal body burden and lead to more serious disturbances in metabolism of important elements such as zinc and copper. Cadmium- and ethanol-induced changes in the homeostasis of these microelements are probably connected with the ability of both xenobiotics to cause metallothionein induction. [ABSTRACT FROM PUBLISHER]

Objective: To study the levels of malonyldialdehyde, marked as the concentration of substances reacting with thiobarbituric acid in liver, brain, serum and kidney in subacute intoxication with low doses of chlorfenvinphos, an organophosphate insecticide. Materials and Methods: The study used male wistar rats, body weight 250 - 280g. The animals received intragastrically, by a gastric tube, once daily 0.1ml/100g of olive oil (the control group) or oil solution of chlorfenvinphos at a dose of 0.02LD50 (0.3 mg/kg b.w.) (the experimental groups). After 14 and 28 days of the experiment, blood samples were collected by cardiac puncture to obtain serum; liver, kidney and brain sections were taken from the animals in anaesthesia. The level of malonyldialdehyde (as TBARS) was determined in homogenates of the organs and in serum. Additionally, serum cholinesterase activity was determined. Results: There was an increase in the tissues as well in the serum malonyldialdehyde level. Proportionally the highest increase in TBARS, as compared to the control, was observed in the liver on day 28 of chlorfenvinphos administration and in the kidney on day 14 of the exposure. Conclusion: In subacute chlorfenvinphos intoxication, lipid peroxidation is increased in the rat liver, serum, kidney and brain, which may cause various health effects in the population exposed to its action. [ABSTRACT FROM AUTHOR]

The activity of glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione S-transferase (GST) was investigated in liver and kidney of rats exposed to cadmium (Cd) and ethanol (EtOH) alone and in combination. Rats were treated with 50 mg Cd/dm³ in drinking water and/or 5 g of EtOH/kg body wt/24 h intragastrically, for 12 weeks. Exposure to Cd led to an increase in GPx and GST activity with a simultaneous decrease in GR activity in the liver. In the kidney of rats treated with Cd, an increase in the activity of GPx and GR was noted. In the EtOH-exposed rats, GPx activity decreased in the liver, but increased in the kidney. Exposure to EtOH caused a reduction in GR activity only in the liver. The co-exposure to Cd and EtOH led to an increase in the liver and kidney GPx activity compared to control. In the rats simultaneously exposed to Cd and EtOH liver activity of GR decreased compared to control, whereas the kidney GR activity increased compared to control as well as to the groups treated with Cd and EtOH seperately. The co-exposure to Cd and EtOH led to an increase in the liver activity of GST compared to the control and EtOH groups. Analysis of variance (ANOVA/MANOVA) revealed that the changes noted in the activity of investigated enzymes in the Cd + EtOH group resulted from the independent action of both Cd or EtOH as well as from their interactive action. Numerous correlations (negative or positive) were noted between the activity of GPx, GR and GST, and the concentration of GSH, Cd and MDA in the liver and kidney. On the basis of our results it can be concluded that changes in the activity of GPx, GR and GST in the liver and kidney may be involved in the mechanism leading to a decrease in GSH concentration in these organs due to exposure to Cd and EtOH alone and in conjunction with each other. [ABSTRACT FROM AUTHOR]

The aim of our study was to evaluate oxidative stress in hepatic mitochondria of rats exposed for 12 weeks alone and in conjunction to cadmium (Cd) (50 mg Cd/dm³, in drinking water) and ethanol (EtOH) (5g of EtOH/kg body wt, intragastrically). In hepatic mitochondria the concentrations of malondialdehyde (MDA), hydrogen peroxide (H2O2), reduced glutathione (GSH) and the activities of manganese superoxide dismutase (MnSOD), glutathione peroxidase (GPx) and glutathione reductase (GR) were measured. After exposure to Cd, an increase in MDA and H2O2 concentrations with a simultaneous decrease in GSH concentration and the activities of MnSOD, GPx and GR were noted. Exposure to EtOH caused an increase in MDA and H2O2 concentration, as well as MnSOD and GPx activities and a decrease in GSH concentration and GR activity. Co-exposure to Cd and EtOH caused an increase in MDA and H2O2 concentration as well as in MnSOD activity and resulted in a decrease in GSH concentration as well as GPx and GR activities in comparison to the control group. The increase in H2O2 concentration and MnSOD activity as well as the decrease in GSH concentration were significant compared to the animals exposed to Cd alone. The changes noted in the investigated parameters in hepatic mitochondria of the rats co-exposed to Cd and EtOH resulted from an independent action of Cd (H2O2, GSH and GPx) or EtOH (H2O2, GSH and MnSOD) as well as from their mutual interaction (GSH, MnSOD and GPx). Based on all results, it can be concluded that exposure to Cd and EtOH, both alone and in conjunction, leads mainly to changes in the concentration of H2O2 and GSH and MnSOD activity in the liver mitochondria. [ABSTRACT FROM AUTHOR]

The involvement of some low-molecular thiol compounds in the mechanisms of peroxidative action of cadmium (Cd) and ethanol (EtOH) was studied. Concentrations of reduced glutathione (GSH), metallothionein (Mt) and thiol (-SH) groups in protein and non-protein fractions were assessed in the homogenates of the liver and kidney of rats exposed to Cd (50 Cd/dm³ of drinking water) and EtOH (5 g EtOH/kg body weight/24 h, intragastrically), singly or in combination, for 12 weeks. Exposure to Cd caused a reduction in the concentration of GSH and non-protein SH groups in the liver and kidneys with a simultaneous increase in Mt level in these organs. The concentration of total SH groups increased only in kidneys. Administration of EtOH had no effect on Mt concentration in both organs, but caused a reduction in the concentration of GSH and non-protein SH groups. A reduction in the level of total SH groups following exposure to EtOH was also noted in the liver. In the group of rats with a simultaneous exposure to Cd and EtOH, GSH concentration was decreased in the liver compared to the control and Cd-exposed animals, and in the kidney in comparison to the control and EtOH-receiving rats. Following the combined exposure to Cd and EtOH, the concentration of non-protein SH groups decreased in the liver and kidneys in comparison to the control and Cd-exposed rats, and in the liver also in comparison to the EtOH group. Mt concentration increased in the liver and kidneys of animals exposed to a combination of Cd and EtOH, compared to the control and EtOH group, but was reduced compared to the Cd group. Combined administration of Cd and EtOH caused an increase in the concentration of total SH groups in the kidneys compared to the control, Cd and EtOH groups. A negative correlation was found between GSH concentration and malondialdehyde (MDA) levels and positive correlation between Mt and MDA. The intensity of lipid peroxidation as well as GSH and Mt concentrations influencing this process in the state of combined exposure to Cd and EtOH results both from independent actions of these substances and interactions between them. The study outcome seems to indicate that the Cd-and EtOH-induced reduction in GSH and non-protein SH groups in the liver and kidneys may be one of the mechanisms that leads to lipid peroxidation in these organs. [ABSTRACT FROM AUTHOR]

Exposure of organisms to extremely low-frequency electromagnetic field (ELF-EMF; 50 Hz) has been increasing in recent decades, which is connected with dynamic technological development. ELF-EMF is considered a stress factor and its effects on organisms are still being investigated. We aimed to determine its impact on the locus coeruleus-noradrenergic (LC-NA) system enabling adaptation to stressful conditions. For this purpose, we exposed rats to 50 Hz ELF-EMF of 1 and 7 mT, 1 h/day for 7 days. The procedure was repeated three times to examine the organism's adaptive capabilities. Subsequently, the concentration of adrenaline, noradrenaline and its metabolite MHPG as well as the expression of the β2-adrenergic receptor was assessed. After the end of each exposure, part of the animals were subjected to a behavioural test to assess the influence of repeated ELF-EMF exposure on stress response to subsequent stress factors. Our research proved that mechanisms underlying the effects of ELF-EMF on stress response include the LC-NA system. ELF-EMF of 1 mT induced adaptive changes in the NA-LC system. However, exposure to 7 mT caused increased activity of the stress system which resulted in sensitization to subsequent, heterotypic (different from the one previously acting) stress factor. As ELF-EMF of 7 mT caused a profound decrease in β2-AR level would strongly inhibit the potential for neuroplastic processes in the hippocampus. Moreover, rats exposed to ELF-EMF of 7 mT showed moderately increased anxiety-related behaviour. Disturbances in NA-LC transmission may underlie the development of some neurodegenerative and psychiatric diseases which indicates the possible involvement of ELF-EMF in the pathogenesis of these disorders., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest to declare., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Since even low-level environmental exposure to cadmium (Cd) can lead to numerous unfavourable health outcomes, including damage to the nervous system, it is important to recognize the risk of health damage by this xenobiotic, the mechanisms of its toxic influence, and to find an effective protective strategy. This study aimed to evaluate, in a female Wistar rat model of current human environmental exposure to Cd (1 and 5 mg/kg of diet for 3-24 months), if the low-to-moderate treatment with this element can harm the brain and whether the supplementation with a 0.1% Aronia melanocarpa L. (Michx.) Elliott berries (chokeberries) extract (AE) can protect against this effect. The exposure to Cd modified the values of various biomarkers of neurotoxicity, including enzymes (acetylcholinesterase (AChE), sodium-potassium adenosine triphosphatase (Na + /K + -ATPase), phospholipase A2 (PLA2), and nitric oxide synthase 1 (NOS1)) and non-enzymatic proteins (calmodulin (CAM), nuclear factor erythroid 2-related factor 2 (Nrf2), and Kelch-like ECH-associated protein 1 (KEAP1)) crucial for the functioning of the nervous system, as well as the concentrations of calcium (Ca) and magnesium (Mg) and some metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in the brain tissue. The co-administration of AE, partially or entirely, protected from most of the Cd-induced changes alleviating its neurotoxic influence. In conclusion, even low-level chronic exposure to Cd may adversely affect the nervous system, whereas the supplementation with A. melanocarpa berries products during the treatment seems a protective strategy.

Cannabidiol (CBD) is a non-psychotomimetic phytocannabinoid derived from Cannabis sativa. It has therapeutic effects in different paradigms of brain injury, acting as a neuroprotectant. As oxidative stress is a primary risk factor for brain damage after neonatal hypoxia, we tested the effect of CBD on oxidative status and non-protein-bound iron accumulation in the immature brain after hypoxia. Moreover, we tested whether cannabidiol affects the accumulation of hypoxia-inducible factor-1 alpha (HIF-1α) which plays a key role in the regulation of cellular adaptation to hypoxia and oxidative stress. We used 7-day-old mice randomly assigned to hypoxic or control groups. Immediately after hypoxia or control exposure, pups were randomly assigned to a vehicle or CBD treatment. 24 h later, they were decapitated and the brains were immediately removed and stored for further biochemical analyses. We found that CBD reduced lipid peroxidation and prevented antioxidant depletion. For the first time, we also demonstrated that CBD upregulated HIF-1α protein level. This study indicates that CBD may effective agent in attenuating the detrimental consequences of perinatal asphyxia., (© 2024. The Author(s).)

Cadmium (Cd) is a prooxidant that adversely affects human health, including the nervous system. As exposure of the general population to this heavy metal is inevitable, it is crucial to look for agents that can prevent the effects of its toxic action. An experimental model on female rats of current lifetime human exposure to cadmium (3-24-months' treatment with 1 or 5 mg Cd/kg diet) was used to test whether low-level and moderate intoxication can exert a prooxidative impact in the brain and whether supplementation with a 0.1% extract from the berries of Aronia melanocarpa L. (Michx.) Elliott (AE; chokeberry extract) can protect against this action. Numerous parameters of the non-enzymatic and enzymatic antioxidative barrier, as well as total antioxidative and oxidative status (TAS and TOS, respectively), were determined and the index of oxidative stress (OSI) was calculated. Moreover, chosen prooxidants (myeloperoxidase, xanthine oxidase, and hydrogen peroxide) and biomarkers of oxidative modifications of lipids, proteins, and deoxyribonucleic acid were assayed. Cadmium dysregulated the balance between oxidants and antioxidants in the brain and led to oxidative stress and oxidative injury of the cellular macromolecules, whereas the co-administration of AE alleviated these effects. To summarize, long-term, even low-level, cadmium exposure can pose a risk of failure of the nervous system by the induction of oxidative stress in the brain, whereas supplementation with products based on aronia berries seems to be an effective protective strategy., Competing Interests: The authors declare no conflicts of interest.

Insects' thermoregulatory processes depend on thermosensation and further processing of thermal information in the nervous system. It is commonly known that thermosensation involves thermoreceptors, including members of the TRP receptor family, but the involvement of neurotransmitters in thermoregulatory pathways remains unstudied. We conducted test to determine whether octopamine, a biogenic amine that acts as a neurotransmitter and neurohormone in insects, is involved in TRP-induced thermoregulatory responses in Periplaneta americana. We used capsaicin, an activator of the heat-sensitive TRP channel, Painless, to induce thermoregulatory response in cockroaches. Then, we evaluated the behavioural (thermal preferences and grooming), physiological (heart rate) and biochemical responses of insects to capsaicin, octopamine and phentolamine - octopaminergic receptor blocker. Capsaicin, similar to octopamine, increased cockroaches' grooming activity and heart rate. Moreover, octopamine level and protein kinase A (PKA) activity significantly increased after capsaicin treatment. Blocking octopaminergic receptors with phentolamine diminished cockroaches' response to capsaicin - thermoregulatory behaviour, grooming and heart rate were abolished. The results indicate that octopamine is a neurotransmitter secreted in insects after the activation of heat receptors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The impact of cadmium (Cd) on the function and structure of the kidney and the potential protective effect of an extract from Aronia melanocarpa L. berries were investigated in a rat model of low- and moderate-level environmental exposure to this heavy metal (1 and 5 mg Cd/kg feed for up to 24 months). The sensitive biomarkers of Cd-induced damage to the kidney tubules (N-acetyl-β-D-glucosaminidase (NAG), alkaline phosphatase (ALP), β2-microglobulin (β2-MG), and kidney injury molecule-1 (KIM-1) in the urine), clinically relevant early markers of glomerular damage (albumin in the urine and creatinine clearance), and other markers of the general functional status of this organ (urea, uric acid, and total protein in the serum and/or urine) and Cd concentration in the urine, were evaluated. The morphological structure of the kidney and inflammatory markers (chemerin, macrophage inflammatory protein 1 alpha (MIP1a), and Bcl2-associated X protein (Bax)) were also estimated. Low-level and moderate exposure to Cd led to damage to the function and structure of the kidney tubules and glomeruli. The co-administration of A. melanocarpa berry extract significantly protected against the injurious impact of this toxic element. In conclusion, even low-level, long-term exposure to Cd poses a risk of kidney damage, whereas an intake of Aronia berry products may effectively protect from this outcome.

Insecticides are dedicated to impair the insect organisms, but also have an impact on other, non-target organisms, including humans. In this way, they became important risk factor for disturbance of physiological homeostasis and can be involved in the development of diseases or in deterioration of existing conditions. The influence of sublethal doses of various insecticides on vertebrates' and invertebrates' organisms has been previously observed. In this paper, we have evaluated the impact of exposure to extremely low dose of neurotoxin, bendiocarb (0.1 nM), a commonly used carbamate insecticide on a model organism in neurobiology-Periplaneta americana. The assessment was performed on all levels of animal organism from molecular (oxidative stress parameters: phosphorylation level of proteins, cAMP level, protein kinase A and C levels, and octopamine) to physiological (heart beat and gas exchange tests) and behavioral (motor skills assay, grooming test). Exposure to such a low level of bendiocarb did not cause direct paralysis of insects, but changed their grooming behavior, decreased heart rate, and increased gas exchange. We also observed the increased parameters of oxidative stress as well as stressogenic response to 0.1 nM bendiocarb exposure. Exposure to a trace amount of bendiocarb also increased sensitivity to effective doses of the same insecticide, thus acts as preconditioning. These results force us to reconsider the possible risk from frequent/continuous exposure to traces of pesticide residues in the environment to human health., (© 2023. The Author(s).)

Obstructive sleep apnea (OSA) is a prevalent, underdiagnosed disease and is considered a risk factor for cardiovascular diseases, depression, accidents, and stroke. Recent clinical practice guidelines for OSA expressed the need for a new clinical tool that establishes the Apnea-Hypopnea Index (AHI) to determine the disease burden. The serum and plasma concentrations of Osteoprotegerin (OPG), Chitinase 3-like protein 1 (YKL-40), and Cardiotrophin-1 (CT-1) in 80 subjects-52 OSA patients, 27 moderate (15 ≤ AHI ˂ 30) and 25 severe (AHI ≥ 30), and 28 non-OSA controls (AHI 0-5)-were determined. Moreover, the Total Oxidative Status (TOS), Total Antioxidative Status (TAS), and Oxidative Stress Index (OSI) were assessed in the serum and plasma to evaluate whether the severity of OSA and the concentrations of OPG, YKL-40, and CT-1 correlate with the oxidative/reductive status. The serum and plasma concentrations of YKL-40 and CT-1 were higher in the OSA group, whereas the serum and plasma concentrations of OPG were lower compared to the control group. The concentrations of OPG, YKL-40, and CT-1 in the serum and plasma correlated with AHI; however, a better correlation of the concentrations was obtained for the above-mentioned proteins in the plasma. The concentrations of YKL-40 and CT-1 in the serum and OPG in the plasma show better diagnostic capabilities for moderate and severe OSA than the concentrations of YKL-40 and CT-1 in the plasma and the concentrations of OPG in the serum.

Introduction: Low-frequency electromagnetic field (50 Hz) (EMF) can modify crucial neuronal processes. Existing data indicate that exposure to EMF may represent a mild stressor and contribute to disturbances of the hypothalamic-pituitary-adrenal (HPA) axis. The important regulatory pathways controlling HPA axis activity include two types of corticosteroid receptors: mineralocorticoid receptors (MRs) and glucocorticoid receptors. They are particularly abundant in the hippocampus, a key locus of HPA axis feedback control. The research aimed at determining whether (1) EMF exhibits hormesis, it means bidirectional action depending on EMF intensity (1 or 7 mT) and (2) repeated EMF exposure changes stress response to subsequent stress factors., Methods: The exposure (7 days, 1 h/day) of adult rats to EMF (1 mT and 7 mT) was repeated 3 times. HPA axis hormones and their receptors were analysed after each following exposure. Moreover, the impact of EMF exposure on hormonal and behavioural responses to subsequent stress factor - open-field test was evaluated., Results: Our data suggest that exposure to EMF can establish a new "set-point" for HPA axis activity. The direction and dynamics of this process depend on the intensity of EMF and the number of exposures. EMF of 1 mT induced an adaptive stress response, but 7 mT EMF caused sensitization. Consequently, EMF changed the vulnerability of the organism to a subsequent stress factor. We have also shown the increase in MR mRNA abundance in the hippocampus of 1 mT EMF-exposed rats, which can represent the possible neuroprotective response and suggest therapeutic properties of EMFs., (© 2022 The Author(s). Published by S. Karger AG, Basel.)

In an in vivo rat model of human exposure to cadmium (Cd; 5 and 50 mg/L, 6 months), whether the supplementation with zinc (Zn; 30 and 60 mg/L, increasing its daily intake by 79% and 151%, respectively) protects against the unfavourable impact of this xenobiotic on the vascular tissue of the abdominal aorta was investigated. The treatment with Cd led to oxidative stress and increased the concentrations of pro-inflammatory interleukin 1β (IL-1β), total cholesterol (TC), triglycerides (TG), and endothelial nitric oxide synthase (eNOS) and decreased the concentration of anti-inflammatory interleukin 10 (IL-10) in the vascular tissue. Cd decreased the expression of intercellular adhesion molecule-1 (ICAM-1), platelet endothelial cell adhesion molecule-1 (PECAM-1), and L-selectin on the endothelial cells. The administration of Zn prevented most of the Cd-induced alterations or at least weakened them (except for the expression of adhesive molecules). In conclusion, Zn supplementation may protect from the toxic impact of Cd on the blood vessels and thus exert a beneficial influence on the cardiovascular system. The increase in the intake of Zn by 79% may be sufficient to provide this protection and the effect is related to the antioxidative, anti-inflammatory, and antiatherogenic properties of this essential element., Competing Interests: The authors declare no conflict of interest.

Studies reported evidence for opposite effects of extremely low-frequency electromagnetic field (EMF): harmful, including the oxidative stress induction, and beneficial, such as the activation of antioxidant defense. People's exposure to EMF is often repeated or prolonged, and it is important to consider the cumulative effect of such kind of exposure on the organism. If changes evoked by repeated exposure to EMF are permanent, responsiveness to other stress factors can be modified. The aims of our study were (1) to evaluate changes in the levels of oxidative stress and antioxidant defense markers in the prefrontal cortex of adult rats after repeated exposure to 1 and 7 mT EMF and (2) to assess whether repeated EMF exposure can modify oxidative/antioxidative status in response to other stress factors. Rats were exposed to EMF 1 h/day for 7 days, one, twice, or three times. After each exposure, 8-isoprostanes, protein carbonyl groups, and the total antioxidant capacity were assessed. Part of the animals, after EMF treatment, was exposed to another stress factor-open field. Results showed that repeated exposure changed the oxidative/antioxidative status depending on the intensity of the EMF and the number of exposures. 1 mT EMF created weak changes in the oxidative status in the brain; however, 7 mT EMF moved the balance to a clearly higher level. The changes in the oxidative status after 1 mT EMF were enough to reduce, and after 7 mT EMF to intensify oxidative processes in response to the next stress. We concluded that the organism might adapt to "weak" EMF, while "strong" EMF exceeds the adaptive capacity of the organism and sensitizes it to subsequent stress, and thus may modulate vulnerability to diseases. Our results also provide new insights into the possible therapeutic properties of the magnetic field, as 1 mT EMF appears to have a potentially protective impact on the brain., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2022 Angelika Klimek et al.)

Cadmium (Cd) is one of the most harmful xenobiotics to which humans are exposed, mainly by the oral route, throughout life. Preventive strategies are searched as low intoxication with this element, among others due to its prooxidative properties, can be deleterious to health and the exposure to it is continuously increasing. Recently, interest has been paid to plant raw materials with a high antioxidative potential to oppose the prooxidative properties of cadmium, such as black chokeberry ( Aronia melanocarpa L. fruit), which is rich in polyphenolic compounds. The study was aimed at assessing whether the chokeberry extract may counteract the prooxidative impact of low-level and moderate repeated intoxication with cadmium on the sublingual salivary gland. The investigation was performed on 96 Wistar rats (females), which were treated with a 0.1% aqueous extract from chokeberries or/and a diet containing 1 or 5 mg Cd/kg for 3 and 10 months, and control animals. The intoxication with cadmium, in a dose- and time-dependent manner, attenuated the enzymatic and nonenzymatic antioxidative potential and increased the concentration of hydrogen peroxide and total oxidative status of the sublingual salivary gland resulting in an occurrence of oxidative stress, enhancement of lipid peroxidation, and oxidative injuries of proteins in this salivary gland. The treatment with the black chokeberry extract during the intoxication with cadmium prevented this xenobiotic-caused oxidative/reductive imbalance and oxidative modifications of proteins and lipids in the salivary gland. The above results allow the conclusion that the consumption of black chokeberry products during intoxication with cadmium can prevent oxidative stress and its consequences in the sublingual salivary gland and thus counteract the unfavourable impact of this xenobiotic on the oral cavity., Competing Interests: There is no conflict of interest., (Copyright © 2021 Barbara M. Onopiuk et al.)

Recovery of function after sensory nerves injury involves compensatory plasticity, which can be observed in invertebrates. The aim of the study was the evaluation of compensatory plasticity in the cockroach (Periplaneta americana) nervous system after the sensory nerve injury and assessment of the effect of electromagnetic field exposure (EMF, 50 Hz, 7 mT) and TGF-β on this process. The bioelectrical activities of nerves (pre-and post-synaptic parts of the sensory path) were recorded under wind stimulation of the cerci before and after right cercus ablation and in insects exposed to EMF and treated with TGF-β. Ablation of the right cercus caused an increase of activity of the left presynaptic part of the sensory path. Exposure to EMF and TGF-β induced an increase of activity in both parts of the sensory path. This suggests strengthening effects of EMF and TGF-β on the insect ability to recognize stimuli after one cercus ablation. Data from locomotor tests proved electrophysiological results. The takeover of the function of one cercus by the second one proves the existence of compensatory plasticity in the cockroach escape system, which makes it a good model for studying compensatory plasticity. We recommend further research on EMF as a useful factor in neurorehabilitation.

The hypothesis that individuals with obstructive sleep apnea syndrome (OSAS) demonstrate oxidative stress in the uvular mucosa that correlates with OSAS occurrence was investigated. A total of 128 participants (mean age 45.8, mean body mass index 30.7, female-male ratio 1:20) were divided into the non-OSAS group (apnea-hypopnea index-AHI < 5) and OSAS-group (AHI ≥ 5), in which mild (5 ≤ AHI < 15), moderate (15 ≤ AHI < 30), and severe (AHI ≥ 30) sub-groups were distinguished. Laryngological examination, Epworth Sleep Scale questionnaire, and home sleep study were performed to obtain AHI, mean oxygen saturation, and lowest oxygen saturation. Total oxidative status (TOS) and total antioxidative status (TAS) were assayed in the uvular mucosa taken during palatoplasty or palatopharyngoplasty. The severity of oxidative stress was expressed as oxidative stress index (OSI). Oxidative/reductive imbalance was noted in the mucosa of the uvula of OSAS individuals, and TAS of the uvular mucosa negatively correlated with the severity of this syndrome. TOS and OSI in the mild, moderate, and severe OSAS were higher than in the non-OSAS group, whereas TAS of the uvular mucosa in the OSAS group was lower compared to the non-OSAS group. In conclusion, oxidative stress in the uvular mucosa is associated with the occurrence of OSAS.

Biological effects of extremely low-frequency magnetic field (ELF-MF) and its consequences on human health have become the subject of important and recurrent public debate. ELF-MF evokes cell/organism responses that are characteristic to a general stress reaction, thus it can be regarded as a stress factor. Exposure to ELF-MF "turns on" different intracellular mechanisms into both directions: compensatory or deleterious ones. ELF-MF can provoke morphological and physiological changes in stress-related systems, mainly nervous, hormonal, and immunological ones. This review summarizes the ELF-MF-mediated changes at various levels of the organism organization. Special attention is placed on the review of literature from the last decade. Most studies on ELF-MF effects concentrate on its negative influence, e.g., impairment of behavior towards depressive and anxiety disorders; however, in the last decade there was an increase in the number of research studies showing stimulating impact of ELF-MF on neuroplasticity and neurorehabilitation. In the face of numerous studies on the ELF-MF action, it is necessary to systematize the knowledge for a better understanding of the phenomenon, in order to reduce the risk associated with the exposure to this factor and to recognize the possibility of using it as a therapeutic agent.

We examined, in a rat model of moderate environmental human exposure to cadmium (Cd), whether the enhanced intake of zinc (Zn) may protect against Cd-caused destroying the oxidative/antioxidative balance and its consequences in the brain. The intoxication with Cd (5 mg/L, 6 months) weakened the enzymatic (superoxide dismutase, glutathione peroxidase, catalase) and non-enzymatic (total thiol groups, reduced glutathione) antioxidative barrier decreasing the total antioxidative status and increased the concentrations of pro-oxidants (hydrogen peroxide, myeloperoxidase) in this organ and its total oxidative status. These resulted in the development of oxidative stress and oxidative modifications of lipids and proteins. The co-administration of Zn (30 and 60 mg/L enhancing this element intake by 79% and 151%, respectively) importantly protected against Cd accumulation in the brain tissue and this xenobiotic-induced development of oxidative stress and oxidative damage to lipids and proteins. Moreover, this bioelement also prevented Cd-mediated oxidative stress evaluated in the serum. The favorable effect of Zn was caused by its independent action and interaction with Cd. Concluding, the enhancement of Zn intake under oral exposure to Cd may prevent the oxidative/antioxidative imbalance and oxidative stress in the brain and thus protect against injury of cellular macromolecules in the nervous system.