Role of antioxidants in the neurobiology of drug addiction: An update.

Relationships between protective enzymatic and non-enzymatic pro-antioxidant mechanisms and addictive substances use disorders (SUDs) are analyzed here, based on the results of previous research, as well as on the basis of our current own studies. This review introduces new aspects of comparative analysis of associations of pro-antixidant and neurobiological effects in patients taking psychoactive substances and complements very limited knowledge about relationships with SUDs from different regions, mainly Europe. In view of the few studies on relations between antioxidants and neurobiological processes acting in patients taking psychoactive substances, this review is important from the point of view of showing the state of knowledge, directions of diagnosis and treatment, and further research needed explanation. We found significant correlations between chemical elements, pro-antioxidative mechanisms, and lipoperoxidation in the development of disorders associated with use of addictive substances, therefore elements that show most relations (Pr, Na, Mn, Y, Sc, La, Cr, Al, Ca, Sb, Cd, Pb, As, Hg, Ni) may be significant factors shaping SUDs. The action of pro-antioxidant defense and lipid peroxidation depends on the pro-antioxidative activity of ions. We explain the strongest correlations between Mg and Sb, and lipoperoxidation in addicts, which proves their stimulating effect on lipoperoxidation and on the induction of oxidative stress. We discussed which mechanisms and neurobiological processes change susceptibility to SUDs. The innovation of this review is to show that addicted people have lower activity of dismutases and peroxidases than healthy ones, which indicates disorders of antioxidant system and depletion of enzymes after long-term tolerance of stressors. We explain higher level of catalases, reductases, ceruloplasmin, bilirubin, retinol, α-tocopherol and uric acid of addicts. In view of poorly understood factors affecting addiction, analysis of interactions allows for more effective understanding of pathogenetic mechanisms leading to formation of addiction and development the initiation of directed, more effective treatment (pharmacological, hormonal) and may be helpful in the diagnosis of psychoactive changes.

The Role of Glutathione in Age-Related Macular Degeneration (AMD).

Age-related macular degeneration (AMD) is a chronic disease that usually develops in older people. Pathogenetic changes in this disease include anatomical and functional complexes. Harmful factors damage the retina and macula. These changes may lead to partial or total loss of vision. The disease can occur in two clinical forms: dry (the progression is slow and gentle) and exudative (wet-progression is acute and severe), which usually starts in the dry form; however, the coexistence of both forms is possible. The etiology of AMD is not fully understood, and the precise mechanisms of the development of this illness are still unknown. Extensive genetic studies have shown that AMD is a multi-factorial disease and that genetic determinants, along with external and internal environmental and metabolic-functional factors, are important risk factors. This article reviews the role of glutathione (GSH) enzymes engaged in maintaining the reduced form and polymorphism in glutathione S-transferase theta-1 (GSTT1) and glutathione S-transferase mu-1 (GSTM1) in the development of AMD. We only chose papers that confirmed the influence of the parameters on the development of AMD. Because GSH is the most important antioxidant in the eye, it is important to know the influence of the enzymes and genetic background to ensure an optimal level of glutathione concentration. Numerous studies have been conducted on how the glutathione system works till today. This paper presents the current state of knowledge about the changes in GSH, GST, GR, and GPx in AMD. GST studies clearly show increased activity in ill people, but for GPx, the results relating to activity are not so clear. Depending on the research, the results also suggest higher and lower GPx activity in patients with AMD. The analysis of polymorphisms in GST genes confirmed that mutations lead to weaker antioxidant barriers and may contribute to the development of AMD; unfortunately, a meta-analysis and some research did not confirm that connection. Unspecific results of many of the parameters that make up the glutathione system show many unknowns. It is so important to conduct further research to understand the exact mechanism of defense functions of glutathione against oxidative stress in the human eye.

Enzymatic Antioxidant Defense and Polymorphic Changes in Male Infertility.

The intensification of oxidative stress and destabilization of the antioxidative defenses of an organism is a consequence of many environmental factors. We considered aspects conditioning male reproductive potential and the functionality of enzymatic antioxidative mechanisms, i.e., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR), and their correlations with Li, Be, B, Na, Mg, Al, P, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Mo, Ag, Cd, Sn, Sb, Ba, Hg, Tl, Pb, and malondialdehyde (MDA), as well as genetic polymorphism IL-4v.C589T (rs2243250) in men with infertility (n = 76). A healthy normozoospermic control (n = 87) was also used. We assessed the impact of negative changes driven by oxidative stress on enzymatic antioxidative mechanisms as well as the role of MDA in the overall process. On this basis, we infer connections between disturbances in enzymatic antioxidative defense and reproductive potential. Based on a molecular analysis of the polymorphism of gene IL-4v.C589T (rs2243250) (chromosome 5) (PCR-RFLP), we considered the relationships among particular genotypes with the possibility of occurrence of male infertility. Concentrations of chemical elements were measured in the blood. The activity of antioxidants and MDA levels were measured in serum. In the infertile group, higher GPx activity was noted (6.56 nmoL·min-1·mL-1, control: 4.31 nmoL·min-1·mL-1; p = 0.004), while GR achieved a greater level in the control (17.74 nmoL·min-1·mL-1, infertile: 15.97 nmoL·min-1·mL-1, p = 0.043), which implies diversified efficiency of the first and second lines of defense. The polymorphism of IL-4v.C589T (rs2243250) was not directly connected with infertility because there were not any differences in the frequency of genotypes between the infertile and control group (p = 0.578). An analysis of genotypes CC and TT (polymorphism IL-4v.C589T (rs2243250)) indicated numerous correlations between antioxidants, chemical elements and MDA. Therefore, chemical economy, antioxidative defense and genetic conditions are connected and jointly shape male reproductive potential. Chemical elements influence antioxidative defense and male fertility; the most important modulators appeared to be Na, Ba, Al and B. The polymorphism of gene IL-4v.C589T (rs2243250) has a limited influence on antioxidative defense and the metabolism of chemical elements.

External and Genetic Conditions Determining Male Infertility.

We explain environmental and genetic factors determining male genetic conditions and infertility and evaluate the significance of environmental stressors in shaping defensive responses, which is used in the diagnosis and treatment of male infertility. This is done through the impact of external and internal stressors and their instability on sperm parameters and their contribution to immunogenetic disorders and hazardous DNA mutations. As chemical compounds and physical factors play an important role in the induction of immunogenetic disorders and affect the activity of enzymatic and non-enzymatic responses, causing oxidative stress, and leading to apoptosis, they downgrade semen quality. These factors are closely connected with male reproductive potential since genetic polymorphisms and mutations in chromosomes 7, X, and Y critically impact on spermatogenesis. Microdeletions in the Azoospermic Factor AZF region directly cause defective sperm production. Among mutations in chromosome 7, impairments in the cystic fibrosis transmembrane conductance regulator CFTR gene are destructive for fertility in cystic fibrosis, when spermatic ducts undergo complete obstruction. This problem was not previously analyzed in such a form. Alongside karyotype abnormalities AZF microdeletions are the reason of spermatogenic failure. Amongst AZF genes, the deleted in azoospermia DAZ gene family is reported as most frequently deleted AZF. Screening of AZF microdeletions is useful in explaining idiopathic cases of male infertility as well as in genetic consulting prior to assisted reproduction. Based on the current state of research we answer the following questions: (1) How do environmental stressors lessen the quality of sperm and reduce male fertility; (2) which chemical elements induce oxidative stress and immunogenetic changes in the male reproductive system; (3) how do polymorphisms correlate with changes in reproductive potential and pro-antioxidative mechanisms as markers of pathophysiological disturbances of the male reproductive condition; (4) how do environmental stressors of immunogenetic disorders accompany male infertility and responses; and (5) what is the distribution and prevalence of environmental and genetic risk factors.

Do agricultural environments increase the reproductive success of White Stork Ciconia ciconia populations in South-Western Poland?

As populations of White Stork Ciconia ciconia have decreased at different rates in Europe, the specific environmental drivers that influence breeding success are a matter of controversy. Here we use body size, blood, and environmental data of a total of 1226 stork nestlings of different ages from a total of 363 nests in three different habitats (meadows, forest-edges, open agricultural landscapes) in S-W Poland to ask whether: 1) natural grassland environments increase the reproductive output in comparison with agricultural landscapes, 2) nestlings from agricultural landscapes differ in health status from nestlings in more natural habitats, 3) differences in environmental stress translate into respective differences in reproductive output and health status of nestlings. There was no significant difference in age corrected body mass and in the temporal increase in nestling mass between the study sites. Clutch sizes were highest and age corrected total clutch mass lowest at the meadow sites while agricultural and woodland sites did not significantly differ. Hemoglobin and red blood cell content were lowest and white blood cell and blood antioxidant concentrations were highest in the meadows indicating higher degrees of environmental stressors. These blood parameters varied strongly among study years. Our study does not confirm that agricultural landscapes are less suited for stork breeding success. We even find some indication of a better health status of nestlings in agricultural environments that might compensate smaller clutch sizes. Our data indicate that reproductive output is multifaceted. As we found some indication of a trade-off between clutch size and health status we argue that only multiple metrics of reproductive success are able to assess the long-term effect of habitat choice on fitness.

Supporting dataset for elemental traits of plant-invertebrate food web components of oilseed rape fields.

This dataset is provided in support of the paper "Edge effect imprint on elemental traits of plant-invertebrate food web components of oilseed rape fields" (Orlowski et al., 2019). Supplementary data are given on the following: (1) the full taxonomic list of invertebrates (n = 12 916) classified into food guilds and functional groups, which were sampled in 34 oilseed rape fields in SW Poland in spring 2015; (2) concentrations of 12 chemical elements measured in invertebrates; (3) the relationships between abundance and percentage (%) in the community of major invertebrate groups, and habitat variables; (4) the statistical tests comparing the concentrations of chemical elements between the different groupings of organisms; (5) the relationships between the elemental traits of oilseed rape plant samples and major functional invertebrate groupings or main taxonomic insect groups, and the habitat variables of oilseed rape fields.

Edge effect imprint on elemental traits of plant-invertebrate food web components of oilseed rape fields.

Of fundamental importance for the functioning of a community is the flow of energy and elements through its components. However, the question of how (if at all) the edge effect of habitats can drive elemental traits of organisms has hitherto been largely neglected issue in ecosystem ecology at the community level. We quantified the abundance of invertebrates and measured the elemental composition (K, Na, Ca, Mg, Cu, Zn, Fe, Mn, As, Cd, Co and Pb) of 15 different organisms within the plant-invertebrate food web (plant - oilseed rape pests/herbivores - pollinators = wild bees - saprovores - predators - parasitoids) sampled in 34 fields of a key bioenergy crop that is an exceptionally strong biodiversity driver, the oilseed rape. Then these were related to the individual field edge habitat features (including typically anthropogenic ones like dirt and tarred roads) measured within a 100 m radius around the invertebrate sampling sites. Our study showed that elemental traits of the plant-invertebrate food web components in oilseed rape crops varied owing to the habitat specificity determined at the relatively small spatial scale of an individual field, and that the elemental traits of these organisms differed from both an inter- and an intra-guild perspective. The major mechanistic explanation for most of these relationships seems to derive from the secondary gut content effect. Determining one single state for the homeostatic/stoichiometric regulation of chemical elements in invertebrates based on the application of whole-body metal concentrations is in principle impossible, because of the unknown noise caused by the inclusion of extracellular portions of metals in the analysis. It is thus imperative to develop consistent principles for assessing elemental traits of organisms that are based on highly sensitive and high-throughput analytical methods for the ionomic profiling of microsamples at the organ, tissue, cellular or even sub-cellular levels.

Variable contribution of functional prey groups in diets reveals inter- and intraspecific differences in faecal concentrations of essential and non-essential elements in three sympatric avian aerial insectivores: a re-assessment of usefulness of bird faeces in metal biomonitoring.

Aerial insectivores through their insect diet can contribute to biotransfer of elements across habitats. We investigate the relationship between dietary composition as expressed by the contributions of six functional invertebrate prey groups (primarily of agriculturally subsidised invertebrates characteristic of agricultural areas in temperate regions of Europe) and concentrations of essential (Na, K, Ca, Mg, Fe, Cu, Zn, Mn, Co) and non-essential (As, Cd, Pb) elements of environmental concern in the faeces of nestlings of three species of avian aerial insectivores - Common Swift Apus apus, Barn Swallow Hirundo rustica and House Martin Delichon urbicum - which breed sympatrically and use apparently similar resources of flying insect prey. There were significant differences between the species for 7 of the 12 elements (Ca, Zn, Cu, Co, As, Pb, Cd); these differences were attributable to the variable dietary composition, even though the concentrations of the elements varied enormously between the faecal samples from the individual species. Partial correlation analysis between the biomass (expressed in mg dry weight) of the six functional prey groups and faecal concentrations of elements showed the highest number of significant relationships for toxic metals (As, Pb and Cd). The results of the General Regression Model explaining faecal element concentrations revealed the different explanatory power of the effects of PCA (of six functional prey groups) dietary scores. A significant fit of GRM was obtained for 7 elements (Na, Mg, Fe, Mn, As, Pb, Cd) for Barn Swallows, 2 elements (Cu, As) for House Martins and 1 element (Mn) for Common Swifts. Overall, the results confirmed our predictions that the biomass of consumed coprophilous taxa and insects from crop habitats was positively correlated with the faecal concentrations of toxic elements. Unexpectedly, however, the faecal samples (primarily those of Common Swifts) that contained many oil-seed rape insect pests had lower Ca, Pb and Cd levels and a higher As level. Our study implies that the cross-boundary transfer of contaminants, primarily non-essential elements, by aerially foraging birds through the considerable accumulation of their faeces has potential consequences for the local biogeochemical cycle and environmental quality.