Stress-induced Responses Research Articles

Hyaluronic acid-curcumin nanoparticles for preventing the progression of experimental autoimmune uveitis through the Keap1/Nrf2/HO-1 signaling pathway

Globally, uveitis is a collection of intraocular inflammatory disorders that affect mainly the uvea, resulting in irreversible blindness and a heavy socioeconomic burden. Excessive autoimmune inflammation and oxidative stress are major drivers that contribute to the initiation and progression of uveitis. Nevertheless, current therapeutic methods for uveitis are limited and are accompanied by several serious adverse effects. Recently, nanotechnology-based antioxidant strategies have provided novel options for the treatment of ocular diseases. Although curcumin (CUR) has prominent antioxidant capacity and reactive oxygen species (ROS) scavenging ability, its low bioavailability and undetermined mechanisms limit its extensive application. This investigation demonstrated that esterified hyaluronic acid-curcumin nanoparticles (HA-CUR NPs) with superior aqueous dispersion exhibited exceptional antioxidant enzyme mimetic activity, incorporating superoxide dismutase (SOD), glutathione (GSH), catalase (CAT), and free radical scavenging ability. Further in vitro and in vivo experimental results validated the protective function of HA-CUR NPs against oxidative stress-induced damage and inflammatory responses, attenuated pathological progression, relieved microvascular damage, and regulated fundus blood flow in retinal vascular networks. This may be attributable to the specific ability of HA-CUR NPs to target the CD44 receptor and activate the Keap1/Nrf2/HO-1 signaling pathway, suggesting a potential mechanism. In summary, this study revealed that HA-CUR NPs, which are composed of a natural product and biomacromolecules with outstanding artificial antioxidant enzyme activities, may be novel agents for effectively and safely treating uveitis and other ROS-related diseases.

Assessment of laparotomy-induced stress response in opium- and morphine-addicted rats by measuring serum glucose and corticosterone levels: an animal experiment

Background: Surgical procedures induce stress responses similar to severe illnesses, activating the metabolic and neuroendocrine systems, especially the hypothalamic-pituitary-adrenal (HPA) axis. The resulting cortisol surge maintains homeostasis but can adversely affect recovery by elevating blood glucose levels and increasing the risk of complications. Given the high prevalence of opium use, especially in the Middle East and southwestern Asia, and its suspected impact on HPA axis function, this study assesses corticosterone (CS) and glucose as indicators of impaired neuroendocrine responses to surgical stress in an animal model with chronic opioid use. Materials and methods: Thirty-six male Wistar rats were randomly assigned to three groups: morphine-addicted, opium-addicted, and control. Addiction was induced by administering increasing doses of morphine or opium in drinking water, as verified by naloxone injections. Laparotomy was performed under ketamine and xylazine anesthesia. Blood samples were collected post-surgery and post-recovery to measure the CS and glucose levels. Results: This study included 30 rats, with ten rats per group. Post-surgery, mean CS levels were higher in the control group compared to the addicted groups, although not significantly higher. Thirty minutes post-recovery, CS levels remained elevated in the addicted groups. Mean glucose levels were significantly higher in the control group both immediately and thirty minutes post-recovery, indicating a sustained hyperglycemic response. No significant differences were observed between addicted groups in glucose levels. Conclusion: Our study suggests that chronic opioid use may reduce the neuroendocrine response to surgical stress, as shown by lower CS levels in addicted rats. This aligns with existing research on opioids and stress responses. However, the small sample size and lack of baseline measurements limit the findings. Future studies should use larger, more diverse samples and additional biomarkers. This pilot study highlights the need for further research on altered stress responses in opioid-addicted patients undergoing surgery, emphasizing the importance of tailored postoperative care.

Rodent Diets Incorporated with Live Biotherapeutic Products (LBPs): An Innovative Dosing Strategy to Support Preclinical Animal Studies on LBP Intervention.

Currently, the administration of live biotherapeutic products (LBPs) in animal-based pre-clinical studies is achieved via oral gavage or voluntary consumption through the water supply. Oral gavage provides the most accurate and precise dosing for the administration of LBPs to laboratory animals; however, it induces stress responses and is labor-intensive, especially when long-term dosing is needed, placing a significant burden on both lab personnel and the subject animals. On the other hand, voluntary LBP consumption through water supply requires less effort and reduces animal stress, but still puts challenges concerning uncontrolled dosing, variations in LBP viability during the dosing period, uneven dosing due to sedimentation of LBPs, and the need for frequent refreshments due to stability and viability concerns in an aqueous environment. To address these problems, we developed lyophilized rodent diet pellets incorporated with stabilized Bioengineered Probiotic Yeast Medicines (BioPYM™), with customizable pellet size, robust mechanical strength, low friability, uniform BioPYM distribution, and proved stability for 10weeks at 4 to 8°C storage, ensuring easy handling and more reliable dosing. Optimal cell viability preservation in dry diets was achieved through optimization of lyoprotectant and blending methods. Pharmacokinetic studies of the shedding of live BioPYM cells and their therapeutic payloads revealed the effective delivery of therapeutic agents targeting rodent gastrointestinal system. Overall, BioPYM-diet pellets represent an improved method for the delivery of LBP, and provide convenient and precise dosing. In addition, this method improves laboratory animal welfare and decreases laboratory workload.

Regulation of ER stress-induced apoptotic and inflammatory responses via YAP/TAZ-mediated control of the TRAIL-R2/DR5 signaling pathway.

In tumors, cancer cells are frequently exposed to adverse environmental conditions that result in endoplasmic reticulum (ER) stress. Mechanical signals emerging from extracellular matrix (ECM) rigidity and cell shape regulate the activity of transcriptional co-activators Yes-associated protein (YAP) and its paralog Transcriptional Coactivator with PDZ-binding motif (TAZ). However, the role of ECM rigidity and YAP/TAZ in tumor cell fate decisions under ER stress remains relatively unexplored. Our results suggest that the YAP/TAZ system plays an important role in the control of ER stress-induced cell death by mechanical signaling arising from ECM stiffness in tumor cells. Mechanistically, YAP/TAZ regulates apoptosis induced by ER stress in tumor cells by controlling the activation of the TRAIL-R2/DR5-mediated extrinsic apoptotic pathway through a dual mechanism. On the one hand, the YAP/TAZ system prevents intracellular TRAIL-R2/DR5 clustering in tumor cells. On the other hand, it inhibits cFLIP down-regulation in tumor cells experiencing ER stress. In addition, YAP/TAZ controls the expression of pro-inflammatory interleukin-8 (IL-8/CXCL8) in tumor cells undergoing ER stress by a TRAIL-R2/DR5/caspase-8-dependent mechanism. Although other mechanisms may also be involved in controlling cell death and inflammation in tumor cells facing environmental stress, our results support a model in which regulation of the subcellular localization and activity of the YAP/TAZ transcriptional co-activators could contribute to the microenvironmental control of cell fate decisions in tumor cells undergoing ER stress.

Stress-Induced Response and Adaptation Mechanisms in Bacillus licheniformis PSKA1 Exposed With Abiotic and Antibiotic Stresses.

Soil ecosystems consist of diverse microbial communities with great potential for ecological and biotechnological applications. These communities encounter various abiotic stresses, which expedite the activation of transient overexpression of heat shock proteins (HSPs). In the present study, a soil bacterium was isolated and identified as Bacillus licheniformis strain PSK.A1, and its growth parameters were optimized before exposing it to heat, salt, pH, and antibiotic stress conditions. Comparative protein expression was analyzed using SDS-PAGE, protein stabilization via protein aggregation assays, and survival through single spot dilution and colony-counting methods under various stress conditions. The pre-treatment of short stress dosage showed endured overall tolerance of bacterium to lethal conditions, as evidenced by moderately enhanced total soluble intracellular protein content, better protein stabilization, comparatively over-expressed HSPs, and relatively enhanced cell survival. The findings highlighted that cells grown under optimal conditions were more susceptible to lethal environments than stressed cells, with their enhanced tolerance linked to the overexpression of 20 distinct HSPs of 17-91 kD. These insights offer the potential for developing strategies to enhance microbial resilience for various applications including bacterial bioprocessing, bio-remediation, and infectious disease management.

Mitochondrial protein import stress.

Mitochondria have to import a large number of precursor proteins from the cytosol. Chaperones keep these proteins in a largely unfolded state and guide them to the mitochondrial import sites. Premature folding, mitochondrial stress and import defects can cause clogging of import sites and accumulation of non-imported precursors, representing a critical burden for cellular proteostasis. Here we discuss how cells respond to mitochondrial protein import stress by regenerating clogged import sites and inducing stress responses. The mitochondrial protein import machinery has a dual role by serving as sensor for detecting mitochondrial dysfunction and inducing stress-response pathways. The production of chaperones that fold or sequester precursor proteins in deposits is induced and the proteasomal activity is increased to remove the excess precursor proteins. Together, these pathways reveal how mitochondria are tightly integrated into a cellular proteostasis and stress response network to maintain cell viability.

Autophagy serves as a protective effect against inflammatory injury of oxidative stress in ARPE-19 cell.

To test the effect of autophagy on inflammatory damage resulting from oxidative stress in adult retinal pigment epithelial cell line (ARPE-19). ARPE-19 cells were pretreated with 200 and 600 µmol/L hydrogen peroxide (H2O2) at various time intervals. The changes of cell morphology, cell viability, reactive oxygen species (ROS) level, autophagic activity, and the inflammatory cytokines (TNFα, IL-6, and TGFβ) were measured at baseline and after treatment with autophagy inducer rapamycin (Rapa) and suppressor wortmannin (Wort) or shATG5. The levels of ROS, cytokines (TNFα, IL-6, and TGFβ), and autophagic activity were significantly increased in ARPE-19 cells after pretreated with H2O2 (all P<0.05) and IL-10 was significantly decreased (P<0.05). By upregulating autophagy, Rapa significantly reduced oxidative stress-induced secretion of pro-inflammatory factors (TNFα and IL-6) and ROS (all P<0.05), yet elevated the production of TGFβ (P<0.05). In contrast, suppression of autophagy through Wort or ATG5 knockdown reduced cell viability, increased cell apoptotic rate, and exacerbated the generation of ROS and inflammatory cytokines (TNFα, IL-6, and TGFβ; all P<0.05). Autophagy demonstrates a protective effect on ARPE-19 cell through mitigating oxidative damage and oxidative stress-induced inflammatory response. Regulation of autophagy may be a potential way for age-related macular degeneration.

Sensory quiescence induces a cell-non-autonomous integrated stress response curbed by condensate formation of the ATF4 and XRP1 effectors

Sensory disabilities have been identified as significant risk factors for dementia but underlying molecular mechanisms are unknown. In different Drosophila models with loss of sensory input, we observe non-autonomous induction of the integrated stress response (ISR) deep in the brain, as indicated by eIF2αS50 phosphorylation-dependent elevated levels of the ISR effectors ATF4 and XRP1. Unlike during canonical ISR, however, the ATF4 and XRP1 transcription factors are enriched in cytosolic granules that are positive for RNA and the stress granule markers Caprin, FMR1, and p62, and are reversible upon restoration of vision for blind flies. Cytosolic restraint of the ATF4 and XRP1 transcription factors dampens expression of their downstream targets including genes of cell death pathways activated during chronic cellular stress and thus constitutes a chronic stress protective response (CSPR). Cytosolic granules containing both p62 and ATF4 are also evident in the thalamus and hippocampus of mouse models of congenital or degenerative blindness. These data indicate a conserved link between loss of sensory input and curbed stress responses critical for protein quality control in the brain.

Unfolded protein response modulates Tyrosinase levels and melanin production during melanogenesis.

Melanocytes protect the body from ultraviolet radiation by synthesizing melanin. Tyrosinase, a key enzyme in melanin production, accumulates in the endoplasmic reticulum (ER) during melanin synthesis, potentially causing ER stress. However, regulating ER function for melanin synthesis has been less studied than controlling Tyrosinase activity. This study investigates the regulatory mechanisms of melanin production, focusing on ER stress and the ER stress-induced response. B16 mouse melanoma cells induced to undergo melanogenesis were treated with unfolded protein response (UPR) inhibitors or chemical chaperones, and their effects on melanogenesis were analyzed. During melanogenesis in B16 cells stimulated by alpha-melanocyte-stimulating hormone (α-MSH), ER stress and UPR activation occurred, accompanied by increased Tyrosinase protein. Reducing IRE1 and ATF6 branch activity lowered melanin levels, while chemical chaperone treatment restored melanin production and increased Tyrosinase levels. UPR activation, linked to elevated Tyrosinase levels, influences melanin production during melanogenesis. Modulating UPR can regulate melanin synthesis and provides a potential new approach for treating pigmentation disorders.

EXERCISE AND IMMUNE FUNCTION FROM GESTALT COHORT: THE BENEFICIAL EMERGING ROLE OF INTEGRATED STRESS RESPONSE

Abstract Exercise significantly impacts immune function by influencing physiological health, which in turn reduces disease susceptibility, combats immune-senescence, and lowers infection risks. Despite these effects, there are still important unanswered questions regarding the impact of exercise on the transcriptome of immune cells, age-related responses, inflammation modulation, and anti-aging benefits. In the Genetic and Epigenetic Signatures of Translational Aging Laboratory Testing (GESTALT) study involving 99 participants aged 22-92, RNA-sequencing was conducted in parallel on 11 immune cell types - B cells, T/CD4+, T/CD8+ (naïve and effector/central memory) cells, monocytes, granulocytes, and natural killer cells - to investigate their correlation with exercise (VO2 peak) using Differential Gene Expression (DGE) and Gene Set Enrichment Analysis (GSEA). Lymphoid B, T and NK cells, exhibited distinct clustering from myeloid cells in both young and old participants (&amp;lt; 44 and &amp;gt;66 years old), with 26 shared genes identified across multiple immune-cell types, reflecting enrichment for 14 energy-mitochondrial pathways associated with increased exercise. Interestingly, while mRNA splicing pathways were upregulated in the young group, older individuals displayed upregulated pathways linked to the Integrated Stress Response (ISR), a signaling pathway previously found to be activated by ER stress, hypoxia, amino acid deprivation, glucose deprivation, and viral infection etc. By utilizing a scoring system for inflammation, senescence, and mitochondria (QuickGO-EBI, SenMayo, and MitoCarta 3.0), we identified clusters of shared genes affected by physical activity. Overall, the findings suggest that stress-induced molecular responses to enhanced aerobic capacity and exercise offer potential benefits for improving the health and well-being of older individuals.

Mechanisms of hyperglycemia formation as a result of traumatic brain injuries (literature review)

Hyperglycemia is a common complication after traumatic brain injury and is associated with poor clinical outcomes. This review examines some of the mechanisms that lead to hyperglycemia after traumatic brain injury, including stress-induced hyperglycemia, inflammatory response, and hypothalamic-pituitary axis dysfunction. Hyperglycemia can lead to lactic acidosis, electrolyte imbalance, inflammation, vascular disorders, and blood brain barrier rupture and increased permeability. Patients who develop hyperglycemia after traumatic brain injury have a high risk of poor outcome and mor tality.

Role of D1- and D2-like dopamine receptors within the CA1 hippocampal region in the stress-induced antinociceptive response in the exposure to acute pain.

Exposure to stressful conditions such as forced swim stress (FSS) induces antinociception. Previous reports determined that dopamine receptors in the CA1 hippocampal area are important in chronic pain processing. Considering that neural mechanisms behind acute and chronic pain differ significantly, in this study, we have investigated the role of dopamine receptors within the CA1 region in the FSS-induced antinociceptive response in the acute pain induced by the tail-flick test in the rat. The cannula was implanted unilaterally in the CA1 region of the animal brain. Animals received drugs or vehicles 5 min before FSS exposure. SCH23390 as the D1-like dopamine receptor (D1R) antagonist and Sulpiride as the D2-like dopamine receptor (D2R) antagonist were microinjected into the CA1 area at three doses (0.25, 1, and 4 μg/0.5 μl vehicle); the vehicle groups received saline instead of SCH23390 and dimethyl sulfoxide instead of Sulpiride. After exposure to FSS, the tail-flick test was done. The findings of this study revealed that FSS significantly attenuates nociceptive response during the tail-flick test ( P < 0.0001). Moreover, intra-CA1 microinjection of SCH23390 and Sulpiride significantly reduces the FSS-induced antinociception in the inducing acute pain ( P < 0.0001). The comparison of effective dose of 50% for D1R and D2R antagonists showed that both receptors in the CA1 almost equally reduce the FSS-induced antinociception in the tail-flick test. The result of this study supports the hypothesis, that the dopaminergic system in CA1 is involved in triggering a stress-induced antinociceptive response in acute pain conditions.

Metabolic response of vitamin C and phenolic compounds in fresh‐cut pineapple induced by pulsed electric fields

AbstractThe loss of nutritional quality is the main factor associated with the perishability of minimally processed foods. In this sense, the application of pulsed electric field (PEF) as an abiotic elicitor to induce stress responses in the metabolism of vitamin C and phenolic compounds in minimally processed pineapple tissues was evaluated. The samples were subjected to treatment with PEF (5 pulses – 3.5 kV m−1) and subsequently stored under refrigeration (10 ± 2°C and 90 ± 5% RH) for a period of 7 days. Pulsed electric field treatment increased total vitamin C (AsA) levels by up to 4.32% up to the third day of storage compared to the control and kept oxidized AsA levels low. This is advocated by the incitement of AsA biosynthesis initiated by the more prominent action of l‐galactone‐1,4‐lactone dehydrogenase—GalLDH and the reusing chemicals (Monodehydroascorbate reductase—MDHA and Dehydroascorbate reductase—DHA) in the ascorbate–glutathione cycle. In the metabolism of phenolic compounds, an increase of 25.26%, 21.48%, and 25.44% was observed for polyphenols, flavonoids, and antioxidant activity in samples treated with PEF in relation to the control, respectively, until the third day of storage. These results were corroborated by the higher phenylalanine ammonia‐lyase (PAL) – PAL synthesis activity and lower polyphenoloxidase—PPO degradative action, which can be seen in the absence of dark spots on the tissues during storage. Considering the consumption and nutritional potential of minimally processed pineapple, the use of PEF is an important technology to increase/preserve the antioxidant potential, ensuring food safety and the visual appearance of the final product.

Priming grapevines with oregano essential oil vapour results in a metabolomic shift eliciting resistance against downy mildew

BackgroundPriming plants with natural products is extensively studied in the agricultural field to reduce the use of synthetic and copper-based pesticides. Previous studies have shown that Oregano essential oil vapour (OEOV) is an effective priming agent against downy mildew (DM) in grapevine (Vitis vinifera L. cv. Chasselas), activating different transcriptomic regulated defence mechanisms.ResultsIn the present study, we complement transcriptomic data with metabolomic insights, confirming some previous regulating patterns and highlighting new mechanisms underlying OEOV-induced resistance. A significant modulation of the phenylpropanoid pathway was noted. The data also confirmed the induction of an oxidative stress response indicated by an up-regulation of reactive oxygen species (ROS)-related genes and a congruent depletion of putative L-glutathione. Interestingly, OEOV promoted the accumulation of organic metabolites such as terpenes and other potential phytoalexins, which could potentially contribute to grapevine innate immune response to Plasmopara viticola.ConclusionOverall, this study uncovered a diverse influence of OEOV on V. vinifera defence mechanisms against DM, enhancing our comprehension of the mode of action of essential oils. This insight offers various prospects for crafting innovative biocontrol products, fostering a more dynamic and sustainable approach to agriculture.

Clinical Efficacy of Endocannabinoid-Mimetic Fatty Acid Amide as a Skin-Soothing Ingredient

Despite the potential benefits of cannabidiol as a skin-soothing ingredient, its regulatory status hampers its general use in cosmetic products in many countries. To develop an alternative to cannabidiol, fatty acid amide molecules mimicking the chemical structure of endocannabinoids were manufactured using a lipase-catalyzed process. A mixture of fatty acid amides from sunflower oil and 1-amino propan-3-ol was synthesized using an immobilized lipase reaction, and the activation of cannabinoid receptor 1 (CB1R) was measured using a cAMP assay. The anti-inflammatory activity of the endocannabimimetic ingredients was evaluated in cultured human monocytes and ex vivo human skin explant models. A clinical study was conducted to address the skin hydration, skin barrier function, and skin redness, and the ratio of the interleukin-1-receptor antagonist (IL1-RA) to IL-1⍺ in corneocytes, as a marker for skin sensitivity, were also measured. As a result, the activation of CB1R by endocannabimimetic ingredients was observed in cAMP assays, and a reduction in inflammatory responses by human monocytes induced by lipopolysaccharide treatment were also observed. External stress-induced inflammatory responses were reduced in ex vivo human skin explants. Improvements in skin hydration and barrier function were observed in a clinical study. A significant decrease in skin redness and the IL-1RA to IL-1⍺ ratio was also observed. Endocannabimimetic ingredients, as alternatives to cannabidiol, can be used in skin-soothing cosmetics to increase skin hydration, improve skin barrier function, and reduce skin sensitivity.

Single-cell RNA sequencing in stroke and traumatic brain injury: Current achievements, challenges, and future perspectives on transcriptomic profiling.

Single-cell RNA sequencing (scRNA-seq) is a high-throughput transcriptomic approach with the power to identify rare cells, discover new cellular subclusters, and describe novel genes. scRNA-seq can simultaneously reveal dynamic shifts in cellular phenotypes and heterogeneities in cellular subtypes. Since the publication of the first protocol on scRNA-seq in 2009, this evolving technology has continued to improve, through the use of cell-specific barcodes, adoption of droplet-based systems, and development of advanced computational methods. Despite induction of the cellular stress response during the tissue dissociation process, scRNA-seq remains a popular technology, and commercially available scRNA-seq methods have been applied to the brain. Recent advances in spatial transcriptomics now allow the researcher to capture the positional context of transcriptional activity, strengthening our knowledge of cellular organization and cell-cell interactions in spatially intact tissues. A combination of spatial transcriptomic data with proteomic, metabolomic, or chromatin accessibility data is a promising direction for future research. Herein, we provide an overview of the workflow, data analyses methods, and pros and cons of scRNA-seq technology. We also summarize the latest achievements of scRNA-seq in stroke and acute traumatic brain injury, and describe future applications of scRNA-seq and spatial transcriptomics.

Insights into the transcriptomic responses of silver-lipped pearl oysters Pinctada maxima exposed to a simulated large-scale seismic survey

BackgroundThe wild stocks of Pinctada maxima pearl oysters found off the coast of northern Australia are of critical importance for the sustainability of Australia’s pearling industry. Locations inhabited by pearl oysters often have oil and gas reserves in the seafloor below and are therefore potentially subjected to seismic exploration surveys. The present study assessed the impact of a simulated commercial seismic survey on the transcriptome of pearl oysters. Animals were placed at seven distances (-1000, 0, 300, 500, 1000, 2000, and 6000 m) from the first of six operational seismic source sail lines. Vessel control groups were collected before the seismic survey started and exposed groups were collected after completion of six operational seismic sail lines (operated at varying distances over a four-day period). Samples from these groups were taken immediately and at 1, 3, and 6 months post-exposure. RNA-seq was used to identify candidate genes and pathways impacted by the seismic noise in pearl oyster mantle tissues. The quantified transcripts were compared using DESeq2 and pathway enrichment analysis was conducted using KEGG pathway, identifying differentially expressed genes and pathways associated with the seismic activity.ResultsThe study revealed the highest gene expression and pathway dysregulation after four days of exposure and a month post-exposure. However, this dysregulation diminished after three months, with only oysters at -1000 and 0 m displaying differential gene expression and pathway disruption six months post-exposure. Stress-induced responses were evident and impacted energy production, transcription, translation, and protein synthesis.ConclusionSeismic activity impacted the gene expression and pathways of pearl oysters at distances up to 2000 m from the source after four days of exposure, and at distances up to 1000 m from the source one-month post-exposure. At three- and six-months post-exposure, gene and pathway dysregulations were mostly observed in oysters located closest to the seismic source at 0 and − 1000 m. Overall, our results suggest that oysters successfully activated stress responses to mitigate damage and maintain cellular homeostasis and growth in response to seismic noise exposure.

Restraint to Induce Stress in Mice and Rats.

Across all animal species, exposure to stressful conditions induces stress responses. One method to study the effects of stress using rodent models is the restraint stress procedure. Restraint stress has been used for decades to investigate changes in physiology, genetics, neurobiology, immunology, and other systems impacted by stress. Due to the ease of performing the procedure, low cost, and numerous modifications to scale for the intensity and duration of stress exposure, a vast literature of studies has used restraint stress in mice and rats. As one example, this study presents previously published data showing the impact of restraint stress in transgenic mice on plasma corticosterone levels and optogenetically-induced norepinephrine release. Acute restraint stress increased plasma corticosterone levels, yet this effect was blunted in mice following repeat restraint stress. However, stimulated norepinephrine release in the bed nucleus of the stria terminalis was increased only in the repeat restraint stress group. These data highlight important considerations of restraint parameters on dependent measures. Additional descriptions of restraint stress in rats are also included for comparison. Finally, the influence of the parameters of the restraint (e.g., acute vs. chronic) and characteristics of the animal subjects (strain, sex, age) are discussed.

Worldwide used bio-insecticides Cry1Ac toxin has no detrimental effects on Episyrphus balteatus but alter the symbiotic microbial communities.

Hoverflies, capable of abilities providing dual ecosystem services including pest control and pollination, are exposed to insecticidal proteins from transgenic plants via pollen and prey aphids. However, the effects of such exposures on hoverflies have never been adequately assessed. Here, we investigated impacts of the most widely used biotoxin Cry1Ac on a representative hoverfly species Episyrphus balteatus through food chain transmission and active toxin exposure. The results showed Cry1Ac can be transmitted into E. balteatus through feeding on Aphis gossypii reared by Bt insect-resistant cotton variety expressing the Cry1Ac toxin, but the biological parameters of E. balteatus including survival rate, growth, development, reproductive capacity, and detoxification-related gene expression, were not significantly affected. Furthermore, the exposure to high-dose Cry1Ac toxin (500μg/mL) resulted in slight increase of 16.67% in the activity of detoxification and antioxidant enzyme catalase in E. balteatus and inhibited the egg hatching, partially inducing stress responses. Notably, the exposure to Cry1Ac toxin disrupted the microbiota homeostasis in E. balteatus, and the relative abundances of three dominant symbiotic bacterial genera (Cosenzaea, Wolbachia, and Commensalibacter) in E. balteatus exhibited a 10%~40% fluctuation under Cry1Ac toxin stress. Taken together, these results suggest Cry1Ac toxin is not lethal to E. balteatus, but it poses a potential threat to its endosymbiotic bacteria.

Piled-supported embankment responses to tunnelling in soft ground: An investigation of settlement and load transfer mechanisms

Piled-supported embankment responses to tunnelling in soft ground: An investigation of settlement and load transfer mechanisms