Metallic nanoparticle actions on the outer layer structure and properties of Bacillus cereus and Staphylococcus epidermidis

Although the antimicrobial activity of nanoparticles (NPs) penetrating inside the cell is widely recognised, the toxicity of large NPs (>10 nm) that cannot be translocated across bacterial membranes remains unclear. Therefore, this study was performed to elucidate the direct effects of Ag-NPs, Cu-NPs, ZnO-NPs and TiO2-NPs on relative membrane potential, permeability, hydrophobicity, structural changes within chemical compounds at the molecular level and the distribution of NPs on the surfaces of the bacteria Bacillus cereus and Staphylococcus epidermidis. Overall analysis of the results indicated the different impacts of individual NPs on the measured parameters in both strains depending on their type and concentration. B. cereus proved to be more resistant to the action of NPs than S. epidermidis. Generally, Cu-NPs showed the most substantial toxic effect on both strains; however, Ag-NPs exhibited negligible toxicity. All NPs had a strong affinity for cell surfaces and showed strain-dependent characteristic dispersion. ATR-FTIR analysis explained the distinctive interactions of NPs with bacterial functional groups, leading to macromolecular structural modifications. The results presented provide new and solid evidence for the current understanding of the interactions of metallic NPs with bacterial membranes.

Reversal Effects of Royal Jelly and Propolis Against Cadmium-Induced Hepatorenal Toxicity in Rats

Heavy metal toxicity is an exponentially growing health problem. In this study, we aimed to assess the protective properties of propolis and royal jelly against cadmium adverse effects. Thirty-two adult male rats were included in our study; kidney and liver functions, histopathological changes, and the level of oxidative stress were evaluated in rats exposed to a daily dose of 4.5 mg cadmium per kilogram of body weight for 1 month and those cotreated simultaneously with either propolis (50 mg/kg/day) or royal jelly (200 mg/kg/day) with cadmium compared to control animals. Cadmium-mediated hepatorenal toxicity was manifested as per the increased oxidative stress, function deterioration, and characteristic histopathological aberrations. The supplementation of royal jelly or propolis restores most of the affected parameters to a level similar to the control group. However, the parameters describing the grade of DNA damage and the interleukin-1β expression in the liver, as well as the levels of malondialdehyde and metallothionein, were slightly elevated compared to controls, despite the regular use of royal jelly or propolis. It is worth noting that better results were found in the case of royal jelly compared to propolis administration. Most likely, the ability of both products to chelate cadmium and contribute in reducing oxidative stress is of great importance. However, further investigations are needed to complement the knowledge about the expected nutritional and medicinal values.

Survival, growth and digestive functions after exposure to nanodiamonds - Transgenerational effects beyond contact time in house cricket strains

The long-term exposure effects of nanodiamonds (NDs), spanning an organism's entire lifespan and continuing for subsequent generation, remain understudied. Most research has focused on evaluating their biological impacts on cell lines and selected organisms, typically over short exposure durations lasting hours or days. The study aimed to assess growth, mortality, and digestive functions in wild (H) and long-lived (D) strains of Acheta domesticus (Insecta: Orthoptera) after two-generational exposure to NDs in concentrations of 0.2 or 2 mg kg-1 of food, followed by their elimination in the third generation. NDs induced subtle stimulating effect that depended on the strain and generation. In the first generation, more such responses occurred in the H than in the D strain. In the first generation of H strain insects, contact with NDs increased survival, stimulated the growth of young larvae, and the activity of most digestive enzymes in mature adults. The same doses and exposure time did not cause similar effects in the D strain. In the first generation of D strain insects, survival and growth were unaffected by NDs, whereas, in the second generation, significant stimulation of those parameters was visible. Selection towards longevity appears to support higher resistance of the insects to exposure to additional stressor, at least in the first generation. The cessation of ND exposure in the third generation caused potentially harmful changes, which included, e.g., decreased survival probability in H strain insects, slowed growth of both strains, as well as changes in heterochromatin density and distribution in nuclei of the gut cells in both strains. Such a reaction may suggest the involvement of epigenetic inheritance mechanisms, which may become inadequate after the stress factor is removed.

Concentration- and Time-Dependent Dietary Exposure to Graphene Oxide and Silver Nanoparticles: Effects on Food Consumption and Assimilation, Digestive Enzyme Activities, and Body Mass in Acheta domesticus

The advancement of nanotechnology poses a real risk of insect exposure to nanoparticles (NPs) that can enter the digestive system through contaminated food or nanopesticides. This study examines whether the exposure of model insect species-Acheta domesticus-to increasing graphene oxide (GO) and silver nanoparticle (AgNP) concentrations (2, 20, and 200 ppm and 4, 40, and 400 ppm, respectively) could change its digestive functions: enzymes' activities, food consumption, and assimilation. We noticed more pronounced alterations following exposure to AgNPs than to GO. They included increased activity of α-amylase, α-glucosidase, and lipase but inhibited protease activity. Prolonged exposure to higher concentrations of AgNPs resulted in a significantly decreased food consumption and changed assimilation compared with the control in adult crickets. A increase in body weight was observed in the insects from the Ag4 group and a decrease in body weight or no effects were observed in crickets from the Ag40 and Ag400 groups (i.e., 4, 40, or 400 ppm of AgNPs, respectively), suggesting that even a moderate disturbance in nutrient and energy availability may affect the body weight of an organism and its overall condition. This study underscores the intricate interplay between NPs and digestive enzymes, emphasizing the need for further investigation to comprehend the underlying mechanisms and consequences of these interactions.

Does Selection for Longevity in Acheta domesticus Involve Sirtuin Activity Modulation and Differential Response to Activators (Resveratrol and Nanodiamonds)?

Sirtuins, often called "longevity enzymes", are pivotal in genome protection and DNA repair processes, offering insights into aging and longevity. This study delves into the potential impact of resveratrol (RV) and nanodiamonds (NDs) on sirtuin activity, focusing on two strains of house crickets (Acheta domesticus): the wild-type and long-lived strains. The general sirtuin activity was measured using colorimetric assays, while fluorescence assays assessed SIRT1 activity. Additionally, a DNA damage test and a Kaplan-Meier survival analysis were carried out. Experimental groups were fed diets containing either NDs or RV. Notably, the long-lived strain exhibited significantly higher sirtuin activity compared to the wild-type strain. Interestingly, this heightened sirtuin activity persisted even after exposure to RVs and NDs. These findings indicate that RV and NDs can potentially enhance sirtuin activity in house crickets, with a notable impact on the long-lived strain. This research sheds light on the intriguing potential of RV and NDs as sirtuin activators in house crickets. It might be a milestone for future investigations into sirtuin activity and its potential implications for longevity within the same species, laying the groundwork for broader applications in aging and lifespan extension research.

Adaptation by death? Cell death-based tolerance to cadmium in 150-generation exposure of Spodoptera exiqua Hübner (Lepidoptera: Noctuidae)

Mechanisms, including autophagy and apoptosis, which serve to regulate and ensure proper organism functions under optimal conditions, play additional defensive roles under environmental pressure. The aim of this study was to test the following hypotheses: (i) elevated autophagy and apoptosis intensity levels, as defensive processes in response to contact with cadmium, are maintained for a limited number of generations and (ii) the number of generations after which levels of cell death processes reach the reference level depends on selective pressure. Cell death processes were assessed by light and transmission electron microscopy, terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL), and cytometric analyses. Model insects (Spodoptera exiqua, Hübner, 1808) were orally exposed to various concentrations of cadmium for 18 generations and compared with reference strains exposed to cadmium or not (control) for over 150 generations. Elevated programmed cell death intensity levels decreased after several generations, indicating tolerance of individuals to cadmium in the diet and verifying the first hypothesis; however, testing the second hypothesis indicated that the number of generations depended not only on pressure intensity, but also on cell death type, since levels of autophagy remained increased for a minimum of 12 generations.

Sericin and melatonin mitigate diethylnitrosamine-instigated testicular impairment in mice: Implications of oxidative stress, spermatogenesis, steroidogenesis, and modulation of Nrf2/WT1/SF-1 signaling pathways

AIMS

This study aimed to investigate the therapeutic influence of combination therapy with sericin and melatonin on attenuating diethylnitrosamine (DEN)-instigated testicular dysfunction in mice and defining the molecular mechanisms involved in orchestrating redox signaling pathways and restoring spermatogenesis and steroidogenesis.

MATERIALS AND METHODS

Different groups of male Swiss albino mice were established and injected with respective drugs intraperitoneally. Semen analysis, hormonal assays, and oxidative stress biomarkers were evaluated. Additionally, melatonin and its receptors, WT1, SF-1, vimentin, Nrf2, and ANXA1 expressions were assessed. Histopathological and ultrastructural features of the testes were investigated by semithin, SEM, and TEM analyses.

KEY FINDINGS

Exposure to DEN exhibited pathophysiological consequences, including a remarkable increase in lipid peroxidation associated with substantial diminutions in SOD, CAT, GPx, GSH, GSH:GSSG, and GST. Furthermore, it disrupted spermatozoa integrity, testosterone, FSH, LH, melatonin, and its receptors (MT1 and MT2) levels, implying spermatogenesis dysfunction. By contrast, treatment with sericin and melatonin significantly restored these disturbances. Interestingly, the combination therapy of sericin and melatonin noticeably augmented the Nrf2, WT1, and SF-1 expressions compared to DEN-treated mice, deciphering the amelioration perceived in antioxidant defense and spermatogenesis inside cells. Furthermore, immunohistochemical detection of ANXA1 alongside histopathological and ultrastructural analyses revealed evident maintenance of testicular structures without discernible inflammation or anomalies in mice administered with sericin and melatonin compared to the DEN-treated group.

SIGNIFICANCE

Our findings highlighted that treatment with sericin and melatonin alleviated the testicular tissues in mice from oxidative stress and dysregulated spermatogenesis and steroidogenesis engendered by DEN.

Hepatoprotective effects of a chemically-characterized extract from artichoke (Cynara scolymus L.) against AFB1-induced toxicity in rats

This study was conducted to investigate the protective potential of a pharmaceutically formulated capsule of artichoke leaf powder (ArLP) against aflatoxin B1 (AFB1)-induced hepatotoxicity in male albino rats. In the 42-day experiment, rats were divided into five equal groups: (i) control, treated with sterile water, (ii) treated with 4% DMSO as AFB1 vehicle, (iii) ArLP of 100 mg kg-1 bw, (iv) AFB1 of 72 µg kg-1 bw, and (v) AFB1 plus ArLP. Exposure of rats to AFB1 resulted in hepatotoxicity as manifested by the intensification of oxidative stress, production of free radicals and significant increase in the activity levels of liver function enzymes relative to the control. Significant reductions in both the enzymatic and non-enzymatic antioxidant markers as well as histopathological abnormalities in liver tissues were also observed. Notably, the combined administration of ArLP with AFB1 clearly reduced AFB1-mediated adverse effects leading to the normalization of most of these parameters back to control levels. These findings clearly highlight the potential benefits of artichoke dietary supplements as a safe and natural solution in counteracting the adverse hepatotoxic effects conferred by AFB1 exposure. Further research is warranted to fully dissect the biochemical and molecular mechanism of action of the observed artichoke-mediated hepatoprotection.

A comprehensive review of recent advances in silk sericin: Extraction approaches, structure, biochemical characterization, and biomedical applications

Silks are natural polymers that have been widely used for centuries. Silk consists of a filament core protein, termed fibroin, and a glue-like coating substance formed of sericin (SER) proteins. This protein is extracted from the silkworm cocoons (particularly Bombyx mori) and is mainly composed of amino acids like glycine, serine, aspartic acid, and threonine. Silk SER can be obtained using numerous methods, including enzymatic extraction, high-temperature, autoclaving, ethanol precipitation, cross-linking, and utilizing acidic, alkali, or neutral aqueous solutions. Given the versatility and outstanding properties of SER, it is widely fabricated to produce sponges, films, and hydrogels for further use in diverse biomedical applications. Hence, many authors reported that SER benefits cell proliferation, tissue engineering, and skin tissue restoration thanks to its moisturizing features, antioxidant and anti-inflammatory properties, and mitogenic effect on mammalian cells. Remarkably, SER is used in drug delivery depending on its chemical reactivity and pH-responsiveness. These unique features of SER enhance the bioactivity of drugs, facilitating the fabrication of biomedical materials at nano- and microscales, hydrogels, and conjugated molecules. This review thoroughly outlines the extraction techniques, biological properties, and respective biomedical applications of SER.

Multigenerational Effects of Graphene Oxide Nanoparticles on Acheta domesticus DNA Stability

The use of nanoparticles like graphene oxide (GO) in nanocomposite industries is growing very fast. There is a strong concern that GO can enter the environment and become nanopollutatnt. Environmental pollutants' exposure usually relates to low concentrations but may last for a long time and impact following generations. Attention should be paid to the effects of nanoparticles, especially on the DNA stability passed on to the offspring. We investigated the multigenerational effects on two strains (wild and long-lived) of house cricket intoxicated with low GO concentrations over five generations, followed by one recovery generation. Our investigation focused on oxidative stress parameters, specifically AP sites (apurinic/apyrimidinic sites) and 8-OHdG (8-hydroxy-2'-deoxyguanosine), and examined the global DNA methylation pattern. Five intoxicated generations were able to overcome the oxidative stress, showing that relatively low doses of GO have a moderate effect on the house cricket (8-OHdG and AP sites). The last recovery generation that experienced a transition from contaminated to uncontaminated food presented greater DNA damage. The pattern of DNA methylation was comparable in every generation, suggesting that other epigenetic mechanisms might be involved.

Joint cadmium and polypropylene microparticle action in cadmium tolerant model insect

Microplastic enlisted as a contaminant of emerging concerns in polluted environments interact with "traditional" contaminants such as metals, causing, among others, their increased accumulation in the body. Harmful effects depend on the exposed animals' possible preadaptation and/or cross-tolerance. The project aimed to assess the role of this phenomenon in the limited toxicity of polypropylene fibers (PPf) in 0%, 0.02%, 0.06, 0.18%, 0.54%, and 1.6% of Cd-supplemented food of larvae of Spodoptera exigua multigenerationally selected to cadmium tolerance. The activity of 20 digestive enzymes (API-ZYM test), defensins, and heat shock proteins, HSP70 levels in the exposed groups were used as biomarkers. PPfs caused the increase of Cd accumulation in the body, while intake of polypropylene microfibers did not change the biomarker levels. Moreover, multigenerational Cd pre-exposure, due to increased tolerance of Cd and, possibly, cross-tolerance, prepares the insects for an additional stressor (PPf) alone and in interaction with cadmium.

Why Is Longevity Still a Scientific Mystery? Sirtuins-Past, Present and Future

The sirtuin system consists of seven highly conserved regulatory enzymes responsible for metabolism, antioxidant protection, and cell cycle regulation. The great interest in sirtuins is associated with the potential impact on life extension. This article summarizes the latest research on the activity of sirtuins and their role in the aging process. The effects of compounds that modulate the activity of sirtuins were discussed, and in numerous studies, their effectiveness was demonstrated. Attention was paid to the role of a caloric restriction and the risks associated with the influence of careless sirtuin modulation on the organism. It has been shown that low modulators' bioavailability/retention time is a crucial problem for optimal regulation of the studied pathways. Therefore, a detailed understanding of the modulator structure and potential reactivity with sirtuins in silico studies should precede in vitro and in vivo experiments. The latest achievements in nanobiotechnology make it possible to create promising molecules, but many of them remain in the sphere of plans and concepts. It seems that solving the mystery of longevity will have to wait for new scientific discoveries.

Age- and Lifespan-Dependent Differences in GO Caused DNA Damage in Acheta domesticus

The rising applicability of graphene oxide (GO) should be preceded by detailed tests confirming its safety and lack of toxicity. Sensitivity to GO of immature, or with different survival strategy, individuals has not been studied so far. Therefore, in the present research, we focused on the GO genotoxic effects, examining selected parameters of DNA damage (total DNA damage, double-strand breaks-DSB, 8-hydroxy-2'-deoxyguanosine-8-OHdG, abasic site-AP sites), DNA damage response parameters, and global methylation in the model organism Acheta domesticus. Special attention was paid to various life stages and lifespans, using wild (H), and selected for longevity (D) strains. DNA damage was significantly affected by stage and/or strain and GO exposure. Larvae and young imago were generally more sensitive than adults, revealing more severe DNA damage. Especially in the earlier life stages, the D strain reacted more intensely/inversely than the H strain. In contrast, DNA damage response parameters were not significantly related to stage and/or strain and GO exposure. Stage-dependent DNA damage, especially DSB and 8-OHdG, with the simultaneous lack or subtle activation of DNA damage response parameters, may result from the general life strategy of insects. Predominantly fast-living and fast-breeding organisms can minimize energy-demanding repair mechanisms.

Synthesis, Characterization, DFT Mechanistic Study, Antimicrobial Activity, Molecular Modeling, and ADMET Properties of Novel Pyrazole-isoxazoline Hybrids

A series of new heterocycle hybrids incorporating pyrazole and isoxazoline rings was successfully synthesized, characterized, and evaluated for their antimicrobial responses. The synthesized compounds were obtained utilizing N-alkylation and 1,3-dipolar cycloaddition reactions, as well as their structures were established through spectroscopic methods and confirmed by mass spectrometry. To get more light on the regioselective synthesis of new hybrid compounds, mechanistic studies were performed using DFT calculations with B3LYP/6-31G(d,p) basis set. Additionally, the results of the preliminary screening indicate that some of the examined hybrids showed potent antimicrobial activity, compared to standard drugs. The results confirm that the antimicrobial activity is strongly dependent on the nature of the substituents linked pyrazole and isoxazoline rings. Furthermore, molecular docking studies were conducted to highlight the interaction modes between the investigated hybrid compounds and the Escherichia coli and Candida albicans receptors. Notably, the results demonstrate that the investigated compounds have strong protein binding affinities. The stability of the formed complexes by the binding between the hybrid compound 6c, and the target proteins was also confirmed using a 100 ns molecular dynamics simulation. Finally, the prediction of ADMET properties suggests that almost all hybrid compounds possess good pharmacokinetic profiles and no signs of observed toxicity, except for compounds 6e, 6f, and 6g.

Silk sericin alleviates aberrant photoperiod-induced alterations in testicular and adrenal steroidogenesis in adult mice

BACKGROUND

Steroidogenesis is a complex process of sequential enzymatic reactions affected by climate change. Animals respond to altered day length, the so-called photoperiod, with changes in physiology. The study aimed to an evaluation of sericin effect in alleviating steroidogenesis disorders induced by disturbed photoperiod in mice.

METHODS

The animals were randomly divided into three groups according to the lighting cycle: a control group with a standard 12_Light:12_Dark cycle, a short-term photoperiod group with a 6_Light:18_Dark cycle, and a long-term photoperiod group with an 18_Light:6_Dark cycle. Both short and long-term groups were subdivided into two equal subgroups: The placebo and the sericin-treated subgroups received, for five weeks from prepubertal throughout adulthood, one intraperitoneal injection per week of the solvent and 1 g sericin/kg body weight, respectively.

RESULTS

Selected oxidative stress parameters and testicular and adrenal steroidogenic capacities of adult mice were measured. After five weeks, the placebo group with impaired photoperiod showed a decrease in the quality and quantity of sperm and a reduction in testosterone, corticosterone, aldosterone, total antioxidant capacity, xanthine oxidase, and melatonin. At the same time, in these groups, there was an increase in the level of aromatase, malondialdehyde, cholesterol, and steroidogenic factor-1 (SF-1) expression in the adrenal cortex and an enhancement in histological lesions. Mice receiving sericin had parameters similar to the control group.

CONCLUSION

Our findings reveal that silk sericin can reduce the stress caused by photoperiod disorders regarding testicular function, sex hormone levels, and sperm quantity and quality. Thus, sericin is a biocompatible protein with a promising potential for its use in the case of organisms living under an abnormal photoperiod.

Does age pay off? Effects of three-generational experiments of nanodiamond exposure and withdrawal in wild and longevity-selected model animals

Nanodiamonds (NDs) are considered a material with low toxicity. However, no studies describe the effects of ND withdrawal after multigenerational exposure. The aim was to evaluate ND exposure (in the 1st and 2nd generations) effects at low concentrations (0.2 or 2 mg kg^-1) and withdrawal (in the 3rd generation) in the wild (H) and longevity-selected (D) model insect Acheta domesticus. We measured selected oxidative stress parameters, immunity, types of cell death, and DNA damage. Most of the results obtained in the 1st generation, e.g., catalase (CAT), total antioxidant capacity (TAC), heat shock proteins (HSP70), defensins, or apoptosis level, confirmed no significant toxicity of low doses of NDs. Interestingly, strain-specific differences were observed. D-strain crickets reduced autophagy, the number of ROS+ cells, and DNA damage. The effect can be a symptom of mobilization of the organism and stimulation of physiological defense mechanisms in long-living organisms. The 2nd-generation D-strain insects fed ND-spiked food at higher concentrations manifested a reduction in CAT, TAC, early apoptosis, and DNA damage, together with an increase in HSP70 and defensins. ROS+ cells and cells with reduced membrane potential and autophagy did not differ significantly from the control. H-strain insects revealed a higher number of ROS+ cells and cells with reduced membrane potential, decreased CAT activity, and early apoptosis. Elimination of NDs from the diet in the 3rd generation did not cause full recovery of the measured parameters. We noticed an increase in the concentration of HSP70 and defensins (H-strain) and a decrease in apoptosis (D-strain). However, the most visible increase was a significant increase in DNA damage, especially in H-strain individuals. The results suggest prolonged adverse effects of NDs on cellular functions, reaching beyond "contact time" with these particles. Unintentional and/or uncontrolled ND pollution of the environment poses a new challenge for all organisms inhabiting it, particularly during multigenerational exposure.

Reduced body length and morphological disorders in Chrysomya albiceps (Diptera: Calliphoridae) larvae reared on aluminum phosphide-treated rabbits

Assessing the time of death based on the growth and development of insects is a critical task in forensic entomology. The rate of larvae development can be affected by a variety of toxins, including pesticides. Aluminum phosphide (AlP) is a low-cost insecticide that has yet to be tested for entomotoxicological significance, despite the fact that it is frequently the cause of fatal poisoning. In this study, we measured the body length of Chrysomya albiceps larvae reared on the carcasses of rabbits poisoned with AlP and analyzed the morphological changes of the larvae reared on the carcasses of rabbits poisoned with AlP. The concentration of AlP in the body of the larvae was significantly lower than in rabbit tissues. Insects from the AlP group had a significantly lower gain in body length. Furthermore, deformities in the larvae were found. Smaller respiratory spiracles were found, as well as a deformed small posterior end with hypogenesis of the posterior respiratory spiracles. Thus, disturbed growth and development of carrion flies found at a crime scene could indicate pesticide poisoning, such as aluminum phosphide.

Time-delayed effects of a single application of AgNPs on structure of testes and functions in Blaps polychresta Forskal, 1775 (Coleoptera: Tenebrionidae)

Silver nanoparticles (AgNPs) are currently the most frequently used engineered nanoparticles. The penetration of AgNPs into ecosystems is undeniable, and their adverse effects on organism reproduction are of fundamental importance for ecosystem stability. In this study, the survival time of the Egyptian beetle Blaps polychresta Forskal, 1775 (Coleoptera: Tenebrionidae), after a single application of 7 different doses, was calculated for 30 days. Then, for the group for which the effect on mortality was calculated as LOAEL - the Lowest Observed Adverse Effect Level, namely, 0.03 mg AgNPs/g body weight (b.w.t.), the following were assessed: structure and ultrastructure of gonads by TEM and SEM, cell viability by cytometry, DNA damage by the comet assay, and a variety of stress markers by spectrophotometric methods. A dose-dependent reduction in the survival time of the insects was revealed. Detailed analysis of the testes of beetles treated with 0.03 mg AgNPs/g b.w.t. revealed numerous adverse effects of nanoparticles in structure and ultrastructure, accompanied by increased apoptosis (but not necrosis), increased DNA damage, increased lipid peroxidation, and decreased levels of antioxidant enzymes. Most likely, the observed results are connected with the gradual release of Ag⁺ from the surface of the nanoparticles, which, once applied, are internalized in cells and become a long-lasting, stable source of Ag⁺ ions. Thus, a single exposure to AgNPs may have the effects of chronic exposure and lead to structural damage and dysfunction of the gonads of B. polychresta.

Multigenerational selection towards longevity changes the protective role of vitamin C against graphene oxide-induced oxidative stress in house crickets

This research was designed to investigate changes that can arise in an invertebrate organism due to stress caused by a strong prooxidant, graphene oxide (GO), and a potent antioxidant, vitamin C. The study aimed to investigate if vitamin C may support convalescence after chronic GO intoxication. We investigated the toxicity of chronic dietary graphene oxide administration in house cricket (Acheta domesticus) types: wild and selected for longevity (with a better developed antioxidant system, conducive to long life). Vitamin C was applied immediately after cessation of graphene oxide intoxication to check if it can support the remedial effect. The condition of cells, DNA stability, catalase activity, and the reproduction potential, measured as the Vitellogenin (Vg) protein expression level, were investigated in control and GO treated groups, recovery groups (-GO), and recovery groups with Vit. C (-GO + Vit.C). In this study vitamin C had no evident remedial effect on the house crickets exposed to graphene oxide. Most probably, the mechanism of vitamin C action, in case of intoxication with nanoparticles, is much more complicated. In the context of the results obtained, it is worth considering whether Vit. C, applied after GO intoxication, causes further disturbance of homeostasis in terms of the cells' redox potential.

Multigenerational graphene oxide intoxication results in reproduction disorders at the molecular level of vitellogenin protein expression in Acheta domesticus

The anthropogenic activities may lead to accumulation of graphene oxide (GO) pollution in the environment. Organisms exposed to chronic or multigenerational GO intoxication can present reproduction depletion. Vitellogenin (Vg) has been used as a parameter for evaluating female fertility due to its importance in embryo nutrition. In this study, we used a promising model organism, Acheta domesticus, which was intoxicated with GO in food for three generations. The aim of the study was to investigate the process of Vg synthesis in crickets depending on the exposure time, GO concentration, and age of the females. The results revealed that chronic GO intoxication had adverse effects on the Vg expression pattern. The 1st generation of insects showing low Vg expression was most affected. The 2nd generation of A. domesticus presented a high Vg expression. The last investigated generation seemed to cope with stress caused by GO, and the Vg expression was balanced. We suggest that the epigenetic mechanisms may play a role in the information transfer to the next generations on how to react to the risk factor and keep reproduction at a high rate. We suspect that chronic GO intoxication can disturb the regular formation of the Vg quaternary structure, resulting in consequences for developing an embryo.

Do nanoparticles cause hormesis? Early physiological compensatory response in house crickets to a dietary admixture of GO, Ag, and GOAg composite

This study aimed to identify the physiological responses of house cricket females following short-term exposure to relatively low dietary doses of graphene oxide (GO, 20 μg · g^-1 food), silver (Ag, 400 μg · g^-1 food) nanoparticles (NPs), or graphene oxide‑silver nanoparticle composite (GO-AgNPs, 20: 400 μg · g^-1 food). Energy intake and distribution were measured on the third, sixth, and tenth day. A semi-quantitative API®ZYM assay of digestive enzyme fingerprints was performed on the third and tenth day of continuous treatment. Physicochemical properties of the NPs were obtained by combining SEM, EDX spectrometry, AFM, and DLS techniques. The obtained results showed decreased energy consumption, particularly assimilation as an early response to dietary NPs followed by compensatory changes in feeding activity leading to the same consumption and assimilation throughout the experimental period (10 days). The increased activities of digestive enzymes in NP-treated females compared to the control on the third day of the experiment suggest the onset of compensatory reactions of the day. Moreover, the insects treated with GO-AgNP composite retained more body water, suggesting increased uptake. The observed changes in the measured physiological parameters after exposure to NPs are discussed in light of hormesis.

The Structure-Properties-Cytotoxicity Interplay: A Crucial Pathway to Determining Graphene Oxide Biocompatibility

Interest in graphene oxide nature and potential applications (especially nanocarriers) has resulted in numerous studies, but the results do not lead to clear conclusions. In this paper, graphene oxide is obtained by multiple synthesis methods and generally characterized. The mechanism of GO interaction with the organism is hard to summarize due to its high chemical activity and variability during the synthesis process and in biological buffers' environments. When assessing the biocompatibility of GO, it is necessary to take into account many factors derived from nanoparticles (structure, morphology, chemical composition) and the organism (species, defense mechanisms, adaptation). This research aims to determine and compare the in vivo toxicity potential of GO samples from various manufacturers. Each GO sample is analyzed in two concentrations and applied with food. The physiological reactions of an easy model Acheta domesticus (cell viability, apoptosis, oxidative defense, DNA damage) during ten-day lasting exposure were observed. This study emphasizes the variability of the GO nature and complements the biocompatibility aspect, especially in the context of various GO-based experimental models. Changes in the cell biomarkers are discussed in light of detailed physicochemical analysis.

Stage-, sex- and tissue-related changes in H2O2, glutathione concentration, and glutathione-dependent enzymes activity in Aiolopus thalassinus (Orthoptera: Acrididae) from heavy metal polluted areas

This study is part of a large project carried out at the Cairo University, Egypt, and focused on assessing physiological and biochemical changes in Aiolopus thalassinus under the influence of environmental pollution with heavy metals (Pb, Cd, Cu, and Zn). The study aimed to investigate parameters related to maintaining redox balance, with particular emphasis on stage-, sex- and tissue-dependent differences in H₂O₂ and glutathione (GSH) levels and activity of selected enzymes involved in GSH metabolism. A noticeable increase in the concentration of H₂O₂ was found, especially in the gut of 5th instar nymphs and females from the highly polluted site. An increase in GSH concentration was significant, especially in the gut of adult A. thalassinus from the high polluted site. However, recycling of reduced form of glutathione in the gut by glutathione reductase (GR) was relevant only for females from the high polluted site. Nymphs and females generally showed higher glutathione S-transferase (GST) activity, especially in the gut. These stage- and sex-related differences can result from different growth dynamic and various reproductive functions of nymphs and both sexes. The digestive track is in direct contact with xenobiotics consumed with food. Nymphs are characterized by vigorous growth, they feed intensively, and their development processes are associated with substantial oxygen consumption. Also, maintaining the antioxidant system at a high level can be more important for females than males due to egg production over a long period. It appears that de novo GSH synthesis is a favorable and cost-effective adaptation mechanism for A. thalassinus living in the high polluted site.

Energy reserves, oxidative stress and development traits of Spodoptera exigua Hübner individuals from cadmium strain

Cadmium as a common environmental stressor may exert highly toxic effects on herbivorous insects. The question was whether possible elevation of an oxidative stress and imbalance of energetic reserves in insects may depend on developmental stage, sex and insect population's multigenerational history of exposure to cadmium. So, the aim of this study was to compare of the development traits, total antioxidant capacity, lipid peroxidation, RSSR to RSH ratio and the concentration of carbohydrates, glycogen, lipids and proteins in whole individuals (larvae or pupae) of Spodoptera exigua originating from two strains: control and selected over 120 generations with sublethal metal concentration (44 Cd mg per dry weight of diet). Generally, the increase of the protein, carbohydrates, glycogen concentration and lipid peroxidation decrease with age of the larvae were found. Revealed cases of a higher mobilisation of carbohydrates and proteins, and changes in total antioxidant capacity or lipid peroxidation, in individuals being under metal exposure, occurred in strain-depended mode. Short-term Cd exposure effect was connected with possible higher engagement of proteins and glycogen in detoxification processes, but also higher concentration of lipid peroxidation. In turn, for long-term Cd exposure effect lower lipids concentration and higher thiols usage seemed to be more specific.

Autophagy: a necessary defense against extreme cadmium intoxication in a multigenerational 2D experiment

Autophagy is a natural process that aims to eliminate malfunctioning cell parts, organelles or molecules under physiological conditions. It is also induced in response to infection, starvation or oxidative stress to provide energy in case of an energy deficit. The aim of this 2-dimensional study was to test if, and if so, how, this process depends on the concentration of cadmium in food (with Cd concentrations from 0 to 352 μg of Cd per g of food (dry weight)-D1 dimension) and the history of selection pressure (160 vs 20 generations of exposure to Cd-D2 dimension). For the study, the 5th instar larvae of a unique strain of the moth Spodoptera exigua that was selected for cadmium tolerance for 160 generations (44 μg of Cd per g of food (dry weight)), as well as 20-generation (11, 22 and 44 μg of Cd per g of food (dry weight)) and control strains, were used. Autophagy intensity was measured by means of flow cytometry and compared with life history parameters: survivability and duration of the 3rd larval stage. The highest values of autophagy markers were found in the groups exposed to the highest Cd concentration and corresponded (with a significant correlation coefficient) to an increased development duration or decreased survivorship in the respective groups. In conclusion, autophagy is probably initiated only if any other defense mechanisms, e.g., antioxidative mechanisms, are not efficient. Moreover, in individuals from pre-exposed populations, the intensity of autophagy is lower.

Oxidative stress parameters, DNA damage and expression of HSP70 and MT in midgut of Trachyderma hispida (Forskål, 1775) (Coleoptera: Tenebrionidae) from a textile industry area

The textile mill industry is one of the major sources of pollution and contributors of metal contaminants to the environment. At the same time, the industry is important for global economy. Pollution caused by the textile industry is characteristic due to a unique set of potentially toxic substances. Darkling beetles (Coleoptera, Tenebrionidae), which live in all biogeographical regions, are especially common in soil quality and soil degradation studies. Our study was designed to assess long-term effects of textile industry (which generates specific pollution) on soil organisms, namely Trachyderma hispida. We especially wanted to find out what changes allow the species to survive and adapt to these specific conditions. Energy-dispersive X-ray spectroscopy of soil and midgut tissues of T. hispida sampled from a polluted site in the Edku textile industrial area in Egypt revealed a high accumulation of chemical elements, compared to a reference site. The concentration of elements in soil was well correlated with their concentration in the midgut of insects. Activity of superoxide dismutase, catalase, ascorbate peroxidase and glutathione S-transferase were negatively correlated with concentration of elements in soil and in the midgut. Meanwhile, malondialdehyde concentration in the midgut revealed an opposite tendency. DNA damage and expression of stress proteins, (HSP70 and metallothionein - MT) were elevated in insects from the polluted site. The activity of textile industry in the area of Edku undoubtedly causes an increase of soil pollution and, in consequence, causes a number of changes in the bodies of organisms living in these areas, including T. hispidus. Therefore, it is necessary to find a solution which limits the emission of waste from the textile industry, as well as to design modern strategies of processing, storing and utilizing it.

DNA damage in Spodoptera exigua after multigenerational cadmium exposure - A trade-off between genome stability and adaptation

Human activity is a serious cause of extensive changes in the environment and a constant reason for the emergence of new stress factors. Thus, to survive and reproduce, organisms must constantly implement a program of adaptation to continuously changing conditions. The research presented here is focused on tracking slow changes occurring in Spodoptera exigua (Lepidoptera: Noctuidae) caused by multigenerational exposure to sub-lethal cadmium doses. The insects received food containing cadmium at concentrations of 5, 11, 22 and 44 μg per g of dry mass of food. The level of DNA stability was monitored by a comet assay in subsequent generations up to the 36th generation. In the first three generations, the level of DNA damage was high, especially in the groups receiving higher doses of cadmium in the diet. In the fourth generation, a significant reduction in the level of DNA damage was observed, which could indicate that the desired stability of the genome was achieved. Surprisingly, however, in subsequent generations, an alternating increase and decrease was found in DNA stability. The observed cycles of changing DNA stability were longer lasting in insects consuming food with a lower Cd content. Thus, a transient reduction in genome stability can be perceived as an opportunity to increase the number of genotypes that undergo selection. This phenomenon occurs faster if the severity of the stress factor is high but is low enough to allow the population to survive.

Vitellogenin expression, DNA damage, health status of cells and catalase activity in Acheta domesticus selected according to their longevity after graphene oxide treatment

The increased use of graphene oxide (GO) raises worrisome questions regarding its possible threat to various ecosystems. Invertebrates represent valuable organisms for environmental studies. The lifespan can influence the ability to cope with toxins, especially those that act via oxidative stress. Two strains of Acheta domesticus, which are selected for longevity, were tested. The main aim was to investigate how GO, when administrated in food, affects: the condition of cells, DNA stability, ROS generation and the reproduction potential (the Vitellogenin (Vg) protein expression). The "recovery effect" - after removing GO from the diet for 15 days - was also measured. The results revealed different responses to GO in the wild (H) and long-living (D) strains. The D strain had a higher catalase activity compared to the H strain on the 25th day of the imago stage. Removing GO from the food resulted in a decrease in the catalase activity to the level of the control. On the 5th day of the imago stage, the H strain had a higher cell mortality than the D strain in the GO-intoxicated groups. There was more DNA damage in the H strain compared to the long-living strain. A remedial effect was seen after the GO was removed from the diet. The total Vg protein expression was higher in the H strain and lower in the D strain. The results indicated a GO concentration-dependent outcome. In both strains, removing the GO from the food led to a high Vg expression. The Vg expression after GO treatment, particularly translation and post-translational processing, should be studied in detail in the future. The D strain of crickets had more specialized mechanisms for maintaining homeostasis than the H strain. Organisms can fight off negative effects of GO, especially when they have systems that are well developed against oxidative stress.

Graphene oxide as a new anthropogenic stress factor - multigenerational study at the molecular, cellular, individual and population level of Acheta domesticus

Although interest in transgenerational phenomena is constantly growing, little is known about the long-term toxicity of nanoparticles. In this study we investigate the multigenerational effects of graphene oxide (GO) which was given to Acheta domesticus in low doses (0.2, 2 and 20 μg·g^-1 of food) for three subsequent generations. We assessed the influence of GO nanoparticles in many contexts, basing on parameters which represented different levels of biological organization: activity of antioxidant enzymes, level of apoptosis, DNA damage, histological analysis, hatching abilities, body mass and body length of insects, as well as their survival rate. The results have shown that exposing insects to nanoparticles over an extended period of time causes surprising intergenerational effects, based on significant differences in the life cycle and reproductive processes, which are not always dose-dependent. The second generation of insects appeared as the most unstable among the parameters that were studied, and did not match trends and patterns in the first and third generation categories. An increase of DNA damage was observed, but only in the third generation. This reduction of genome stability can be perceived as an essential element of adaptation, leading to an increase of genotype variants, which then undergo selection.

OP0331-HPR BARRIERS TO SHARED DECISION-MAKING WITH WOMEN OF REPRODUCTIVE AGE AFFECTED BY CHRONIC INFLAMMATORY DISEASES

Background:

Previous research has indicated that women with a chronic inflammatory disease (CID) are likely to discontinue treatment during pregnancy. [1] Reasons for this are complex, including sub-optimal integration of shared decision-making (SDM) into practice.

Objectives:

The purpose of this study was to assess: 1) physicians’ competencies in risk assessment, treatment and management of women of reproductive age (WoRA) with a CID, and 2) clinical gaps, barriers and challenges to SDM with these patients.

Methods:

A mixed-methods needs assessment was conducted. [2] Participants included rheumatologists and dermatologists practicing in Germany, United Kingdom, or United States, with at least three years of experience. Exposure to patients diagnosed with rheumatoid arthritis, psoriatic arthritis, axial spondyloarthritis or psoriasis was required. A first phase involved collection and thematic analysis of data from semi-structured interviews to identify main challenge areas. The second phase consisted of online surveys to validate and quantify identified challenges, gaps and barriers. Chi-square and Kruskal Wallis H statistical tests were performed to assess differences by specialty, country and gender. Qualitative and quantitative findings were triangulated with insight from experts in medical education and relevant behavioural and clinical fields. [3] The present summary reports data pertaining to rheumatologists only.

Results:

A total of 24 interviews and 173 surveys were completed with rheumatologists. Depending on the country and specific item, 22% to 64% reported having sub-optimal knowledge of treatment options, patient education aids, and strategies to assess treatment adherence among WoRA with a CID (see figure 1). In addition, 36% reported having sub-optimal knowledge of methods to achieve SDM. Unplanned pregnancies were reported as a barrier to prescribing biologics to WoRA with a CID. Yet, 61% of rheumatologists reported having sub-optimal skills discussing contraceptive methods with patients. In addition, 41% reported having sub-optimal skills adjusting treatment according to changes in pregnancy status or child-bearing aspirations. Few differences in clinical gaps were observed by gender. Notably, a greater proportion of male rheumatologists reported having sub-optimal skills approaching WoRA in a way that makes them feel comfortable discussing their health concerns, compared to female rheumatologists (52% vs. 30%, p=0.046). This skill gap was identified as a contributing barrier to SDM with these patients.

Conclusion:

This study identified multiple challenges, gaps and barriers relevant to rheumatologists that prevent optimal SDM, risk assessment, treatment and management of WoRA with CID. Findings may be used to develop medical education and continuous professional development interventions for target learners.

References:

[1]Tsao NW, Lynd LD, Sadatsafavi M, Hanley G and De Vera MA. Patterns of biologics utilization and discontinuation before and during pregnancy in women with autoimmune diseases: a population-based cohort study.Arthritis Care Res.,2018;70(7):979-986.

[2]Creswell JW, Klassen AC, Plano Clark VL, Smith KC. Best practices for mixed methods research in the health sciences, 2nd Ed. Bethesda: NIH, 2018:541-545,.

[3]Turner SF, Cardinal LB, Burton RM, A triangulation-based framework and roadmap.Organ. Res. Methods,2017;20(2): 243-26.

Acknowledgments:

This research was financially supported with educational funds from UCB BioPharma SRL. The authors thank T. Kellner for his contribution.

Disclosure of Interests:

Suzanne Murray: None declared, Rebecca Fischer-Betz Consultant of: UCB, Speakers bureau: Abbvie, Amgen, Biogen, BMS, Celgene, Chugai, GSK, Janssen, Lilly, Medac, MSD, Novartis, Roche, UCB, Pfizer., Monica Augustyniak: None declared, Jenny Murase Consultant of: I have led advisory boards for UCB., Speakers bureau: I have done non-branded talks on psoriasis management in women for UCB., Catherine Nelson-Piercy Consultant of: I have received consultancy fees from UCB, Speakers bureau: I have received fees for speaking from UCB., Ivo Vlaev Consultant of: For UCB., Speakers bureau: For UCB, Pfizer, Novartis and boehringer Ingelheim., Cecile Ecoffet Shareholder of: UCB, Employee of: UCB, Morgan Peniuta: None declared, Dean Jenkins Employee of: UCB

Protective role of zinc in Spodoptera exigua larvae under 135-generational cadmium exposure

The aim of this study was to investigate whether zinc supplementation modulates cadmium toxicity in the beet armyworm Spodoptera exigua selected for 135 generations towards cadmium tolerance. To achieve this, larvae originating from three laboratory populations of S. exigua (control strain - C; cadmium-intoxicated for 135 generations strain - Cd, and control strain intoxicated with Cd for 1 generation - CCd) were additionally exposed to zinc in three concentrations (Zn1, 400 μg Zn·g^-1 dry mass of food; Zn2; 200 μg Zn·g^-1 dry mass of food; Zn3, 100 μg Zn·g^-1 dry mass of food). As the markers of toxicity, a life history traits (the duration of L4 and L5 stages), cellular (DNA damage indices) and biochemical parameters (ADP/ATP ratio and ATP and HSP70 concentrations) were chosen. The duration of larval stages of Zn supplemented larvae was prolonged, while cellular and biochemical indicators, in general, appeared to be lower in comparison to the insects from respective reference groups in each laboratory populations. Moreover, the range of the differences depended on zinc concentration in food. We can suspect that zinc supplementation contributed to the protection of S. exigua individuals against negative effects of cadmium intoxication, probably at the cost of growth rate. Significant differences in the response pattern between insects from different laboratory populations indicate that the influence of additional stress factors is dependent on the overall condition of animals and their previous adaptation to other stressors.

Microevolution or wide tolerance? Level of stress proteins in the beet armyworm Spodoptera eqigua hübner (Lepidoptera: Noctuidae) exposed to cadmium for over 150 generations

The aim of this study was to investigate whether the cadmium tolerance developed in the beet armyworm Spodoptera exigua selected for over 150 generations may be related to synthesis of the stress proteins metallothioneins (Mts) and 70 kDa heat shock proteins (HSP70). To achieve this, six S. exigua strains (control, k), 150-generation Cd exposure strain (cd), and four 18-generation Cd exposure strains differing in Cd concentration (cd44, cd22, cd11, cd5) were reared. Stress protein level was measured in the midgut of the 5th larval stage after 1-6, 12 and 18 generations. Cd contents was measured in the pupae. Unlike Cd concentration, which depended on metal contents in food but was not generation-dependent, the pattern of Mts and HSP70 concentrations changed in experimental strains from generation to generation. Stress protein levels in the insects exposed to the highest Cd concentration (the same as in the 150-generation Cd exposure strain), initially higher than in the control strain, after the 12th generation did not differ from the level measured in the control strains. It seems therefore that stress proteins play a protective role in insects of lower tolerance to cadmium. The tolerance developed during multigenerational exposure probably relies on mechanisms other than Mt and HSP70 synthesis.

Immune response of juvenile common carp (Cyprinus carpio L.) exposed to a mixture of sewage chemicals

Pharmaceuticals and household chemicals are important components of municipal sewage. Many of them are biologically active, disrupting not only hormonal regulation of aquatic animals but also, indirectly, disturbing their immunological protection. In the environment, chemicals rarely act as individual substances, but as elements of mixtures. Therefore, the aim of this study was to check whether the acute laboratory exposure of common carp juveniles to a mixture of ibuprofen, sodium dodecyl sulphate (SDS), dimethyl sulfoxide (DMSO) and 17 α-ethynylestradiol in increasing concentrations, modifies the levels of innate immunity (lysozyme, C-reactive protein) as well as general stress (metallothioneins, heat shock proteins HSP70) markers in brain, liver, gills, spleen and mucus. The levels of the markers were measured by an immunodetection technique. Not only do the pharmaceuticals and household chemicals impair immunological reactions of young carp in various tissues but also do that in a concentration-dependent manner in the liver, gills, spleen and mucus. This has a very important implication, since it may result in higher sensitivity of young fish to pathogens due to energy allocation to defence processes. The comparisons of the pattern of stress reactions in the studied organ samples indicated that mucus appeared to be a good, non-invasive material for monitoring of environmental state and fish conditions.

Antioxidant enzyme activity in responses to environmentally induced oxidative stress in the 5th instar nymphs of Aiolopus thalassinus (Orthoptera: Acrididae)

The response of antioxidant enzymes to oxidative environmental stress was determined in 5th instar nymphs of Aiolopus thalassinus (Orthoptera: Acrididae) collected from sites with different level of pollution with heavy metals, PO₄^3-, and SO₄^2-. The high polluted site induced higher DNA damage to individuals compared to the control site. The highest values of tail length (TL), tail moment (TM), and percent of DNA in tail (TDNA) were found in the gut of 5th instar nymphs from a high polluted site. Also, protein carbonyls and lipid peroxide levels were significantly higher in insects collected from polluted sites compared to those from the control site. A strong positive correlation between both protein carbonyl and lipid peroxide concentration and the pollution level of the sites was found in all tissues of the insects. The activity of superoxide dismutase (SOD) in the brain of insects collected from the high polluted site was significantly higher than that in the thoracic muscles and gut. We observed strong inhibition of catalase (CAT) activity. This effect was apparently caused by pollutants present at the high polluted site. The level of pollution significantly influenced polyphenol oxidase (PPO) activity in A. thalassinus nymphs in all examined tissues. The highest values were observed in the brain. The relationship between pollution and ascorbate peroxidase (APOX) activity in the examined tissues had no clear tendency. However, the lowest APOX activity was observed in individuals from the low polluted site. Level of pollution of sampling sites, oxidative stress biomarkers, and enzymatic response in A. thalanthsis 5th instar were negatively or positively correlated. Oxidative damage parameters, especially the percent of severed cells, lipid peroxides, and the activity of APOX, can be perceived as good markers of environmental multistress.

Reproduction and development of Spodoptera exigua from cadmium and control strains under differentiated cadmium stress

The growth and development of living organisms is programmed in genes, but exogenous factors (e.g. cadmium) may modulate endogenous information. Heavy metals may disturb physiological functions and accumulate in the tissues. The insects under prolonged heavy metal stress show some modifications in their metabolism management. The aim of this study was to compare the reproduction and development between individuals of S. exigua from the strain, exposed over 130 generations to sublethal concentration of cadmium (44 mg Cd/kg dry weight of larval diet), and the individuals from the control strain, both additionally exposed to different concentration of cadmium (22-704 mg Cd/kg dry weight of larval diet). The exposure to various cadmium concentrations in the diet revealed survival difference between the cadmium and the control animals at the larvae stage. The differences between adults were not evident. The telomere length (responsible for the duration of a lifespan) in the cadmium strain was shorter in the females than in the males and the individuals from the control strain. TERF1 gene expression (indirectly responsible for the telomere length) was higher in the individuals from the cadmium strain 24 hrs after eclosion. The significant reduction in the larvae body mass was observed in both strains, when the metal concentration was equal to or higher than 264 mg/kg dry weight of larval diet. The EC50 values (defined as of body mass loss), calculated 48 hours after cadmium exposure of individuals from control and cadmium strains, were respectively 632 and 725 mg Cd/kg dry weight of diet. However, some difference in reproduction (the total number of eggs laid and the oviposition time) between the strains appeared only in the groups fed on the uncontaminated diet. The control females laid almost two times more eggs than those from the cadmium strain, and the control ones had more than two times longer oviposition time than the females from the cadmium strain. The fluctuation was also noted in the size of eggs and the hatching success on the following days when both strains were compared, while the hatching success was higher for the insects from the cadmium strain. In conclusion, the insects from the cadmium strain are more resistant to cadmium contamination, as it is evidenced by the EC50 parameter. However, the females from the cadmium strain start laying eggs statistically later, have shorter telomeres and slightly reduced TERF1 gene expression, but hutching success in the strain is significantly higher when compared with the control individuals.

Chronic toxicity of nanodiamonds can disturb development and reproduction of Acheta domesticus L

The use of nanodiamonds in numerous materials designed for industry and medicine is growing rapidly. Consequently health and environmental risks associated with the exposure of humans and other biota to nanodiamonds-based materials are of the utmost importance. Scarcity of toxicological data for these particles led us to examine the potentially deleterious effects of nanodiamonds in model insect species, Acheta domesticus (Orthoptera) chronically exposed to ND in its diet. Organism-level end-point indices (lifespan, body weight, consumption, caloric value of faeces, reproduction) revealed adverse changes in the treated crickets in comparison with the control. Preliminary studies of oxidative stress level in the offspring of ND-treated crickets suggest toxicity of these particles limited to the exposed individuals. EPR analysis showing increase of radical signal in the faeces of ND-fed crickets led us to propose novel mechanism of nanodiamonds toxicity that is discussed in the light of literature data.

CAPSULE

Development and reproduction of Acheta domesticus can be disturbed by the chronic exposure to nanodiamonds.

Reduced fecundity and cellular changes in Acheta domesticus after multigenerational exposure to graphene oxide nanoparticles in food

Despite the fact that the demand for graphene and its derivatives in commercial applications is still growing, many aspects of its toxicity and biocompatibility are still poorly understood. Graphene oxide, which is released into the environment (air, soil and water) as so-called nanowaste or nanopollution, is able to penetrate living organisms. It is highly probable that, due to its specific nature, it can migrate along food chains thereby causing negative consequences. Our previous studies reported that short-term exposure to graphene oxide may increase the antioxidative defense parameters, level of DNA damage, which results in numerous degenerative changes in the gut and gonads. The presented research focuses on reproductive dysfunction and cellular changes in Acheta domesticus after exposure to GO nanoparticles in food (concentrations of 20 and 200 μg·g^-1 of food) throughout their entire life cycle. The results showed that long-term exposure to GO caused a significant decrease in the reproductive capabilities of the animals. Moreover, the next generation of A. domesticus had a lower cell vitality compared to their parental generation. It is possible that graphene oxide can cause multigenerational harmful effects.

Molecular changes in vitellogenin gene of Spodoptera exigua after long-time exposure to cadmium - Toxic side effect or microevolution?

The reproduction of pest insects is a continuously ongoing issue, especially in the environmental pollution context. Natural or artificial stressing factors enforce a kind of trade-off, most often between growth/survival and reproduction, which improves fitness of the organism. Harmful factors, such as cadmium, can affect the vitellogenesis leading to reduction of yolk synthesis and egg production. The aim of this study was to assess whether 130-generational selection to cadmium in food might have induced change in vitellogenesis of Spodoptera exigua. We analyzed the level of Vg gene expression in S. exigua from the control and the cadmium strain at regular time intervals within 48h after eclosion. The full sequence of Vg gene was also compared between strains. The vitellogenin gene expression in both strains was time-dependent. This dependence was more visible in the control strain. In the cadmium strain the vitellogenin expression was significantly lower, comparing with the control strain in the first day after eclosion but increased significantly in the second day. The sequenced CDS (5286bp long) of the control and the cadmium strains were translated into protein sequences containing both 1761 aa. The protein sequences comparison revealed that there is one amino acid change at aa position 1282. Multiple alignments of six orthologous proteins from different species showed that amino acid change is located in the conserved position. Long-lasting exposure to cadmium resulted in permanent mutation in vitellogenin gene. We do not know yet if the mutation can improve fitness of the cadmium-selected insects. However, we can suppose that the mutation is neutral or even beneficial. The mutation and most probably additional effects of cadmium exposure have an influence on the vitellogenin expression. Some modification in the expression of the vitellogenin receptor are also likely to be important.

Cross tolerance in beet armyworm: long-term selection by cadmium broadens tolerance to other stressors

Long lasting exposure of animals to stressing factor may lead to the selection of population able to cope with the stressor at lower cost than unexposed individuals. The aim of this study was to assess whether 130-generational selection of a beet armyworm to cadmium in food might have induced tolerance also to other stressors. The potential tolerance was assessed by means of unspecific stress markers: HSP70 concentration, DNA damage level, and energy budget indices in L5 larval instars of beet armyworm. The animals originated from Cd-exposed and control strains exposed additionally in a short-term experiment to high/low temperature or pesticide-spinosad. The application of the additional stressors caused, in general, an increase in the levels of studied parameters, in a strain-dependent manner. The most significant increase was found in HSP70 level in the individuals from the Cd-strain exposed to various spinosad concentration. Therefore, multigenerational contact with cadmium caused several changes that enable the insect to survive under a chronic stress, preparing the organism to the contact with an additional, new stressor. This relationship may be described as a sort of cross tolerance. This may, possibly, increase the probability of population survivorship and, at the same time, decrease the efficiency of pesticide-based plant protection efforts.

Biomonitoring of genotoxicity of industrial fertilizer pollutants in Aiolopus thalassinus (Orthoptera: Acrididae) using alkaline comet assay

Phosphate fertilizer industry is considered as one of the main sources of environmental pollutants. Besides solid waste products, e.g. phosphates, sulphates, and heavy metals, also atmospheric pollutants, such as hydrofluoric acid fumes (HF), sulphur dioxide (SO₂), nitrogen oxides (NO₂), and particulate matter with diameter up to 10 μm (PM₁₀) can be dangerous. Genotoxic effect of these pollutants was monitored by assessing the DNA damage using alkaline comet assay on cells from brain, thoracic muscles and gut of Aiolopus thalassinus collected at three sites (A-C) located at 1, 3, and 6 km away from Abu-Zaabal Company for Fertilizers and Chemical Industries. Control site was established 32 km from the source of pollution, at the Cairo University Campus. The level of the DNA damage was significantly higher in insects from polluted sites comparing to that from the control site. A strong negative correlation between percentage of cells with visible DNA damage (% of severed cells) and the distance of the sites from Abu-Zaabal Company was found. The best parameter for monitoring of fertilizer pollutants is % of severed cells. Possible impact of Abu-Zaabal Company (extremely high concentration of phosphates and sulphates in all the polluted sites) on DNA integrity in A. thalassinus tissues was discussed. The potential use of the comet assay as a biomonitoring method of the environmental pollution caused by fertilizer industry was proposed. Specific pollution resulting from the activity of the fertilizer industry can cause comparable adverse effects in the organisms inhabiting areas up to 6 km from the source of contamination.

Evaluation of Candidate Reference Genes for Quantitative Gene Expression Analysis in Spodoptera exigu a after Long-time Exposure to Cadmium

Studies on the transcriptional control of gene expression play an important role in many areas of biology. Reference genes, which are often referred to as housekeeping genes, such as GAPDH, G3PDH, EF2, RpL7A, RpL10, TUBα and Actin, have traditionally been assumed to be stably expressed in all conditions, and they are frequently used to normalize mRNA levels between different samples in qPCR analysis. However, it is known that the expression of these genes is influenced by numerous factors, such as experimental conditions. The difference in gene expression underlies a range of biological processes, including development, reproduction and behavior. The aim of this study was to show the problems associated with using reference genes in the qPCR technique, in a study on inbred strains of Spodoptera exigua selected toward cadmium resistance. We present and discuss our results and observations, and give some recommendations concerning the use and limitations of housekeeping genes as internal standards, especially in research on insects. Our results suggest that holometabolism and poikilothermia, as well as time since metamorphosis and the level of exposure to the selective factor (cadmium in this case), have a significant effect on the expression of reference genes.

Short-term in vivo exposure to graphene oxide can cause damage to the gut and testis

Graphene oxide (GO) has unique physicochemical properties and also has a potentially widespread use in every field of daily life (industry, science, medicine). Demand for nanotechnology is growing every year, and therefore many aspects of its toxicity and biocompatibility still require further clarification. This research assesses the in vivo toxicity of pure and manganese ion-contaminated GO that were administrated to Acheta domesticus with food (at 200mgkg^-1 of food) throughout their ten-day adult life. Our results showed that short-term exposure to graphene oxide in food causes an increase in the parameters of oxidative stress of the tested insects (catalase - CAT, total antioxidant capacity - TAC), induces damage to the DNA at a level of approximately 35% and contributes to a disturbance in the stages of the cell cycle and causes an increase of apoptosis. Moreover, upon analyzing histological specimens, we found numerous degenerative changes in the cells of the gut and testis of Acheta domesticus as early as ten days after applying GO. A more complete picture of the GO risk can help to define its future applications and methods for working with the material, which may help us to avoid any adverse effects and damage to the animal.

Evaluation of oxidative stress biomarkers in Aiolopus thalassinus (Orthoptera: Acrididae) collected from areas polluted by the fertilizer industry

The waste products of the fertilizer industry such as heavy metals, but especially phosphates and sulphates, are a serious problem that influences the structure and functioning of ecosystems. The levels of Cd, Pb, Zn, Cu, sulphates and phosphates were measured in soil samples from four sites: a control and sites that were 1, 3 and 6 km (sites A-C) away from the Abu-Zaabal Fertilizer Company. Oxidative stress markers (protein carbonyls, lipid peroxides), antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), polyphenoloxidase (PPO) and ascorbate peroxidase (APOX)) were evaluated in the tissues of Aiolopus thalassinus, collected from the corresponding sites. The highest concentrations of Cu and Zn were found in the soil from site A. The level of protein carbonyls in the brain, thoracic muscles and gut of the males and females from sites A, B and C were 11.82, 4.38, 5.97 (males) and 19.04, 16.65, 7.79 (females) times higher, respectively, compared to the individuals from the control site. Lipid peroxides levels in both sexes were significantly correlated with the distance from the source of the contamination. In the brain, thoracic muscles and gut of the males and females collected from site A, the level of lipid peroxides were 15.41, 23.49, 11.50 (males) and 25.36, 11.34, 15.37 (females) times higher compared to the values of the control animals. The activities of SOD, PPO, CAT and APOX were significantly affected by the environmental pollutants. The enzymatic and non-enzymatic oxidative markers in the Aiolopus thalassinus, a common insect species that inhabits various ecosystems, can also be used as a relevant biomarker of the pollution that is caused by the fertilizer industry.

Lifespan differences between queens and workers are not explained by rates of molecular damage

The biological processes that underlie senescence are of universal biological importance, yet they remain poorly understood. A popular theory proposes that senescence is the result of limited investment into mechanisms involved in the prevention and repair of molecular damage, leading to an accumulation of molecular damage with age. In ants, queen and worker lifespans differ by an order of magnitude, and this remarkable difference in lifespan has been shown to be associated with differences in the expression of genes involved in DNA and protein repair. Here we use the comet assay and Western Blotting for poly-ubiquitinated proteins to explore whether these differences in expression lead to differences in the accumulation of DNA damage (comet assay) or protein damage (protein ubiquitination) with age. Surprisingly, there was no difference between queens and workers in the rate of accumulation of DNA damage. We also found that levels of ubiquitinated proteins decreased with age, as previously reported in honeybees. This is in contrast to what has been found in model organisms such as worms and flies. Overall, these results reveal that the link between investment into macromolecular repair, age-related damage accumulation and lifespan is more complex than usually recognised.

Phenotypic Plasticity, Epigenetic or Genetic Modifications in Relation to the Duration of Cd-Exposure within a Microevolution Time Range in the Beet Armyworm

In the case of the pests inhabiting metal polluted or fields where the use of pesticides is common, a natural selection of resistant individuals can occur. This may pose serious problems for humans, agriculture, as well as the economies of many countries. In this study, the hypothesis that multigenerational (120 generations) exposure to cadmium of a beet armyworm population could be a selecting factor toward a more efficient DNA protection was verified. The hemocytes of individuals from two culture strains (control and Cd-exposed) were treated with H2O2 (a DNA-damaging agent) or PBS (reference). The level of DNA damage was assessed using the Comet assay immediately and 5, 15 and 30 min. after the treatment. The immediate result of the contact with H2O2 was that the level of DNA damage in the hemocytes of the insects from both strains increased significantly. However, in the cells of the Cd-exposed individuals, the level of DNA damage decreased over time, while in the cells from the control insects it remained at the same level with no evidence of repair. These results suggest that efficient defense mechanisms may exist in the cells of insects that have prolonged contact with cadmium. Some evolutionary and trade-off aspects of the phenomenon are discussed. In a wider context, comparing the results obtained in the laboratory with field studies may be beneficial for understanding basic mechanisms of the resistance of an organism. To summarize, the high potential for the repair of DNA damage that was observed in the insects from the cadmium strain may confirm the hypothesis that multigenerational exposure to that metal may possibly contribute to the selection of insects that have a wider tolerance to oxidative stress. However, our investigations of polymorphism using AFLP did not reveal differences between the two main insect strains.

The level of DNA damage in adult grasshoppers Chorthippus biguttulus (Orthoptera, Acrididae) following dimethoate exposure is dependent on the insects' habitat

The comet assay was used to study the DNA damage that was induced by dimethoate in the hemocyte cells of adult Chorthippus biguttulus grasshoppers (Insecta: Orthoptera) that originated from two sites with varying levels of pollution. The primary focus of the study was to examine whether continuous exposure to environmental stress can modify the effect of pesticides on genome stability. After three days of acclimation to laboratory conditions, the level of DNA damage in the hemocytes of Bow-winged grasshoppers was within a similar range in the insects from both areas. However, the level of DNA damage following dimethoate treatment was significantly higher in the insects from the reference area (Pogoria) than in the individuals from the heavily polluted location (Szopienice). Four hours after pesticide treatment, the Tail DNA (TDNA) in the hemocytes of the male and female specimens from Pogoria was as high as 75% and 50% respectively, whereas the values in males and females from Szopienice only reached 30% and 20%, respectively. A rapid decrease in DNA damage was observed in both populations 24 h after the pesticide application. The habitat of an insect (site), the administration of the dimethoate (treatment), and the period following the application of the pesticide (time), all significantly influenced the levels of DNA damage. No interactions related to TDNA were observed between the variables 'sex' and 'treatment'. Similarly, the variable 'sex', when analyzed alongside 'treatment' and 'site' (the area from which the insects were collected), or 'treatment' and 'time' had no influence on TL. Exposure to dimethoate undoubtedly contributed to the formation of DNA damage in the hemocytes of adult C. biguttulus. However, the level of damage was clearly dependent on the place where the insects were captured.

Oxidative stress and genotoxic effects of diamond nanoparticles

Due to the unique and useful properties of nanodiamonds (ND), their production and use is rapidly increasing. Thus, more of these particles will be released into the environment and organisms will inevitably be exposed to them. The current knowledge about the toxicity of ND, especially in vivo toxicity, is fragmentary. In this study, the toxicity of nanodiamonds was assessed in Acheta domesticus following chronic exposure to different nominal concentrations of ND (20 and 200µgg(-1) food) administrated in food for the entire lifespan. The activity of oxidative stress enzymes (catalase, glutathione peroxidase), total antioxidant capacity, as well as the level of heat shock protein were determined. A significant increase in all of the measured parameters was observed after seven weeks of exposure in individuals exposed to higher concentrations of ND (200µgg(-1) food). In animals exposed to lower concentrations of ND (20µgg(-1) food), there were few significant changes to these parameters. Analysis of DNA damage performed after fourteen weeks using the comet assay revealed DNA instabilities in the insects, especially the ones that had been exposed to the higher doses of ND. These findings may suggest that the toxicity of ND is concentration dependent. While high doses interact in a toxic manner, trace amounts, which are more likely in the environment, might be safe for organisms. Extreme caution should be taken when handling nanodiamonds.

Genotoxic effects of starvation and dimethoate in haemocytes and midgut gland cells of wolf spider Xerolycosa nemoralis (Lycosidae)

The aim of this study was to assess the genotoxic effects of starvation and dimethoate (organophosphate insecticide) in female and male wolf spiders Xerolycosa nemoralis (Lycosidae) exposed to the stressors under laboratory conditions. DNA damage was measured in haemocytes and midgut gland cells using the comet assay. In response to the two stressing factors, both cell types showed %TDNA, tail length (TL) and OTM values higher in males than in females. Level of DNA damage in haemocytes was greater than in midgut gland cells. In both sexes, the strongest genotoxicity was recorded at single application of dimethoate. After five-time exposure to the pesticide, genotoxic effects of a single dose were sustained in males and reduced to the control level in females. Starvation stress was well tolerated by the females, in which neither cell type was affected by DNA damage. However, in male haemocytes food deprivation induced severe DNA damage, what suggests suppression of the defence potential at prolonged starvation periods.