Stresses

Fungi, from saprophytes to pathogens, face predictable daily fluctuations in light, temperature, humidity, and nutrient availability. To cope, they have evolved an internal circadian clock that confers a major adaptive advantage. This review critically synthesizes current knowledge on the molecular architecture and physiological relevance of fungal circadian systems, moving beyond the canonical Neurospora crassa model to explore the broader phylogenetic diversity of timekeeping mechanisms. We examine the core transcription-translation feedback loop (TTFL) centered on the FREQUENCY/WHITE COLLAR (FRQ/WCC) system and contrast it with divergent and non-canonical oscillators, including the metabolic rhythms of yeasts and the universally conserved peroxiredoxin (PRX) oxidation cycles. A central theme is the clock’s role in gating cellular defenses against oxidative, osmotic, and nutritional stress, enabling fungi to anticipate and withstand environmental insults through proactive regulation. We provide a detailed analysis of chrono-pathogenesis, where the circadian control of virulence factors aligns fungal attacks with windows of host vulnerability, with a focus on experimental evidence from pathogens like Botrytis cinerea, Fusarium oxysporum, and Magnaporthe oryzae. The review explores the downstream pathways—including transcriptional cascades, post-translational modifications, and epigenetic regulation—that translate temporal signals into physiological outputs such as developmental rhythms in conidiation and hyphal branching. Finally, we highlight critical knowledge gaps, particularly in understudied phyla like Basidiomycota, and discuss future research directions. This includes the exploration of novel clock architectures and the emerging, though speculative, hypothesis of “chrono-therapeutics”—interventions designed to disrupt fungal clocks—as a forward-looking concept for managing fungal infections. Full article

Among the numerous compounds released as a result of human activities, endocrine-disrupting chemicals (EDCs) have attracted particular attention due to their widespread detection in human biological samples and their accumulation across various ecosystems. While early research primarily focused on their effects on reproductive health, it is now evident that EDCs may impact neurodevelopment, altering the integrity of neural circuits essential for cognitive abilities, emotional regulation, and social behaviors. These compounds may elicit epigenetic modifications, such as DNA methylation and histone acetylation, that result in altered expression patterns, potentially affecting multiple generations and contribute to long-term behavioral phenotypes. The effects of EDCs may occur though both direct and indirect mechanisms, ultimately converging on neurodevelopmental vulnerability. In particular, the gut–brain axis has emerged as a critical interface targeted by EDCs. This bidirectional communication network integrates the nervous, immune, and endocrine systems. By altering the microbiota composition, modulating immune responses, and triggering epigenetic mechanisms, EDCs can act on multiple and interconnected pathways. In this context, elucidating the impact of EDCs on neurodevelopmental processes is crucial for advancing our understanding of their contribution to neurological and behavioral health risks. Full article

The climbing perch, Anabas testudineus, is one of the most widely distributed freshwater amphibious fishes in South and Southeast Asia, exhibiting terrestrial movements. Our experimental study aimed to investigate endocrinological and biochemical changes in the blood of climbing perch associated with their terrestrial movements. To achieve this, the fish were divided into two groups: one group was exposed to aquatic conditions for twenty minutes, while the other group was subjected to terrestrial conditions for the same duration through rapid water level decrease. In terrestrial conditions, the fish predominantly exhibit movements on land, whereas in aquatic environments, they primarily remain immobile or swim. Elevated levels of stress-induced cortisol and glucose after short-term exposure indicate a high-stress response involving both neuroendocrine and metabolic mechanisms. Changes in the activity of aspartate aminotransferase and increased concentrations of triglycerides in the blood serum suggest energy mobilization through aerobic metabolic pathways. Extreme environmental changes did not affect thyroid axis function, including deiodination, thereby maintaining essential physiological activities under new conditions. Additionally, the anaerobic metabolic pathway appears to be minimally utilized at the onset of terrestrial movement, as no significant changes in lactate dehydrogenase concentrations were observed. Overall, the terrestrial movements of the climbing perch are likely predominantly forced and associated with high stress. Full article

Masting, or the synchronous and intermittent production of seeds, can have profound consequences for Tropical Montane Cloud Forest (TMCF) tree populations and the trophic webs that depend on their mass flowering and seeds. Over the past 80 years, the importance of Fagus mexicana Martínez (Mexican beech) masting has become apparent in terms of conservation and management, promoting regeneration, and conserving endangered tree species, as well as the conscientious development of edible beechnuts as a non-timber forest product. The establishment of the relict-endemic Mexican beech is unknown, and several microenvironmental factors could influence natural regeneration. Thus, this study was conducted in two well-preserved Mexican beech forests to assess the influence of light incidence and soil moisture on the natural germination and seedling establishment of beeches. During two masting years (2017 and 2024), we assessed in situ beechnut germination and establishment. We tested the effect of the microenvironment of the oldest beeches on beechnut germination and seedling establishment. Our study highlights the complexity of the microenvironment of old beeches influencing the early stages of establishment and provides insights into possible conservation actions aimed at mitigating the impact of environmental change and humans. Full article

This study was conducted to examine the combined effects of monensin (MS) and 3 µm polystyrene microplastics (PEMPs) on the growth and stress-associated physiological responses of Microcystis aeruginosa under controlled laboratory conditions [temperature: 20 ± 1 °C, lighting: (30 ± 4) µmol m⁻² s⁻¹ (12 h:12 h light–dark photoperiod), growth medium: BG-11]. The experiments included MS concentrations of 0, 50, 250, and 500 µg/L and PEMPs concentrations of 0.25, 1.25, and 6 mg/L. Measurements included optical density (OD₇₃₀), chlorophyll ‘a’, cellular protein content, oxidative stress, and the activities of catalase (CAT) and guaiacol peroxidase (GPX). M. aeruginosa exhibited a significant increase in growth on day 7 at elevated MS concentrations across all PEMP levels. Similarly, MS and PEMP treatments had a significant interactive effect on cellular protein content on day 7. However, their combined effect on chlorophyll ‘a’ production was not significant. Oxidative stress measurements showed a dose-dependent decrease with increasing MS concentrations under PEMP administrations. Enzyme activity assays indicated that CAT activity increased while GPX activity decreased with higher MS concentrations. The results imply that co-contamination of PEMPs and MS has a significant impact on the growth and stress physiology of M. aeruginosa in aquatic ecosystems. Full article

Understanding how thermal variability affects marine ectotherms is essential for predicting species resilience under climate change. We investigated the physiological responses of juvenile Nodipecten subnodosus (lion’s paw scallop), offspring of two genetically distinct populations (Bahía de Los Ángeles and Laguna Ojo de Liebre), reared under common garden conditions and exposed to three temperature regimes: constant, regular oscillation, and stochastic variability. After 15 days of exposure, scallops underwent an acute hyperthermia challenge. We measured metabolic rates, scope for growth (SFG), tissue biochemical composition, and oxidative stress markers (SOD, CAT, GPx, TBARS). No significant differences were detected between populations for most traits, suggesting that phenotypic plasticity predominates over evolutionary divergence in thermal responses. However, the temperature regime significantly influenced metabolic, biochemical and oxidative stress markers, indicating that scallops in variable conditions compensated through improved energy balance and food assimilation but also showed higher oxidative stress compared to the constant regime. Following acute hyperthermic exposure, energy demand escalated, compensatory mechanisms were impaired, and scallops attained a state of physiological maintenance and survival under stress, irrespective of their population or prior thermal regime exposure. Full article

While genetic mechanisms in neurodevelopmental disorders are well studied, the mechanisms of environmental factors such as prenatal stress are less understood. Our lab previously characterized miRNA changes associated with stress during pregnancy in mouse brains and in maternal blood from mothers of children with ASD and indicated that prenatal stress can be linked to epigenetic markers. These miRNAs could be used as discovery biomarkers for stress exposure, as well as predictors of neurodevelopmental outcomes. In this pilot study, we gathered saliva samples and stress survey questionnaires from 83 pregnant African American women (ages 18–40) at the time of their ultrasound performed at 20 weeks. miRNA analysis was performed on the 10 highest- and 10 lowest-stress subjects. Out of 6631 miRNAs examined, 34 had significant differential expression, with 5 being upregulated and 29 downregulated in the high-stress group. Predicted targets of differentially expressed miRNAs revealed significant enrichment in neurodevelopmental pathways, including forebrain development, sensory system development, and neuronal growth regulation. This may suggest the potential developmental salience of these miRNA profiles. Future research will examine the neurodevelopmental outcomes of these pregnancies to determine the predictive potential of these miRNAs. This may help identify individuals at greatest risk after stress exposure during pregnancy. Full article

Abiotic stresses are the major factors limiting grape production in the world. They significantly impede grape growth and production. However, during the grape production stage, plant growth regulators play a crucial role in regulating grape developmental progress, especially methyl jasmonate (MeJA). The exogenous MeJA participates in different crop production, gene expression, signaling transduction, natural defense, stress resistance, hormone balance, osmotic regulation, cellular metabolic process, and thermostatic regulation. Grape crop resilience to different abiotic and biotic stresses was overall fascinated by exogenous applications of MeJA. Therefore, in this review, we focus on the MeJA hormone in abiotic stress relief and discovery, application, significance, occurrence, growth via development, stress responses, interaction, molecular modulation, and biological signaling in the grape. Exogenous MeJA in abiotic stress responses explained the physiological change and the signaling pathway has emerged as one of the key plant metabolic processes vs. photosynthetic productivity, playing a substantial role in gene expression, quality parameters, fruit attribution, protein differentiation, cellular programming, and reprogramming, and tolerance mechanism. MeJA hormone has been discovered after a broader study as abiotic stress-responsive methyl jasmonate/Jasmonic acid, which could be a pivotal target not only for grape production but also for other crops. Full article

From germination to harvest, cereal crops are constantly exposed to a broad spectrum of abiotic stresses that significantly hinder their growth and productivity, posing a serious threat to global food security. Seed resilience and performance are foundational to sustainable agriculture, making the development of efficient, low-cost, and environmentally friendly strategies to enhance seed vigor and stress tolerance a critical priority. Seed priming has emerged as a promising pre-sowing technique that involves exposing seeds to specific organic or inorganic compounds under controlled conditions to improve their physiological and biochemical traits. Various priming techniques—including halopriming, chemical priming, osmopriming, hormonal priming, hydropriming, biopriming, and nanopriming—have been successfully applied in cereal crops to alleviate the adverse effects of environmental stressors. These treatments trigger a cascade of metabolic and molecular responses, including the modulation of hormonal signaling, enhancement of antioxidant defense systems, stabilization of cellular structures, and upregulation of stress-responsive genes. Together, these changes contribute to enhanced seed germination, improved growth and performance, and greater adaptability to abiotic stress conditions. This review provides a comprehensive overview of seed priming strategies in cereal crops, emphasizing their mechanisms of action and their impact on plant performance in challenging environments. Full article

Background: Exposure to early life stress significantly increases the risk of psychopathology later in life. However, the impact of early life stress on the gut microbiome and its potential role in mental health outcomes remains insufficiently understood. This narrative review examines the current knowledge on how early life stress and its associated consequences may affect the gut microbiome, with a particular focus on conditions such as anxiety, depression, and post-traumatic stress disorder. Method: A comprehensive literature search was conducted in the PubMed and Web of Science databases between January and February 2025, covering studies published between 2015 and 2025. Results: Early life stress can profoundly impact cognitive function and neurodevelopment, with maternal early-life nutrition playing a significant role in modulating the effects of prenatal and postnatal stress. Early life stress influences the gut microbiome, disrupting its composition and function by altering the synthesis of microbial metabolites, neurotransmitters, and the activation of key metabolic pathways. However, the precise role of the gut microbiome in modulating stress responses during childhood and adolescence has not yet been fully elucidated. Conclusions: Several studies have demonstrated an association between early life stress and the gut microbiome. However, causality has not yet been established due to the numerous intrinsic and extrinsic factors influencing the microbiome-gut–brain axis. In the coming years, research on key microbial regulators, such as short-chain fatty acids, amino acids, and psychobiotics, may represent a promising approach for addressing central nervous system alterations linked to early life stress. Thus, further studies will be necessary to evaluate their potential as therapeutic agents. Full article

Hans Selye’s stress concept, first introduced in the 1930s, has undergone substantial evolution, extending beyond biology and medicine to influence diverse academic disciplines. Initially, Selye’s General Adaptation Syndrome (GAS) described nonspecific physiological responses to stressors exclusively in mammals, without addressing other biological systems. Consequently, the concept of stress developed independently in biology and medicine, shaped by distinct physiological contexts. This review provides a historical overview of stress research, highlights both parallels and divergences between the stress responses of plants and animals, and integrates insights from traditional Eastern philosophies. We propose an updated GAS framework that incorporates the dynamic balance among reactive oxygen species (ROS), reactive nitrogen species (RNS), and reactive sulfur species (RSS) within the broader context of oxidative stress. We highlight the ionotropic glutamate receptor (iGluR) family and the transient receptor potential (TRP) channel superfamily as minimal molecular architectures for achieving GAS. This perspective expands the classical stress paradigm, providing new insights into redox biology, interspecies stress adaptation, and evolutionary physiology. Full article

The present research was designed to assess the potential effect of SNP to alleviate salinity stress injury in fig transplants cv. Conadria. One-year-old transplants irrigated with saline water (6.25 ds/m) were treated with sodium nitroprusside (SNP) at four concentrations (0, 50, 100 and 200 µM); untreated transplants exposed to salt stress represent the positive control, while the non-stressed transplants represent the negative control. Salt stress showed a considerable increase in lipid peroxidation, proline, sodium, chloride content and antioxidant enzyme activity and reduced vegetative growth parameters, photosynthetic pigments, phenolic content and K/Na ratio. SNP reduced salt stress injury in fig transplants through maintaining higher values of growth parameters and photosynthetic pigment content, reducing sodium accumulation and maintaining the integrity of cell membrane lipids. SNP-treated transplants accumulated higher amounts of potassium ions and a higher K/Na ratio. SNP at 100 µM was the most efficient treatment in enhancing the response to salt stress. Overall, the results show that SNP application is a promising practice for alleviating salt stress on fig transplants. Full article

Plant-growth-promoting rhizobacteria (PGPR) influence soil fertility, plant growth, tolerance to abiotic stress, resistance to herbivorous insects, and plant interactions with other organisms. While the effects of PGPR on plant growth, fruit yield, and induced defense responses have been extensively studied, the consistent positive outcomes have fueled rapid expansion in this research field. To evaluate PGPR impacts on plant growth and interactions with phytophagous insects, we conducted a systematic meta-analysis using publications from electronic databases (e.g., PubMed, Web of Science) that reported PGPR effects on plants and insects. Effects were categorized by plant family, PGPR genus, insect feeding guild, and insect–host specialization. Our analysis revealed that PGPR generally enhanced plant growth across most plant families; however, the magnitude and direction of these effects varied significantly among PGPR genera, indicating genus-specific interactions with host plants. When assessing PGPR-mediated reductions in phytophagous insects, we found that Pseudomonas, Rhizobium, and Bacillus exhibited the weakest negative effects on insect populations. PGPR significantly reduced both monophagous and polyphagous insects, with the most pronounced negative impacts on sucking insects (e.g., aphids, whiteflies). This study highlights critical patterns in PGPR-mediated plant growth promotion across taxa and the related differential effects on phytophagous insect activity. These insights advance our understanding of PGPR applications in agroecological production systems, particularly for integrated pest management and sustainable crop productivity. Full article

Aflatoxin B1 (AFB1), a potent mycotoxin, poses a significant threat to animal health through contaminated feed. Our study aims to investigate the neurotoxic effects of AFB1in chickens, with a special emphasis on the brain. Seven-day-old chickens were fed AFB1-contaminated feed (5 mg of AFB1/kg of feed) for two weeks, after which neurobehavioral assessments and biochemical analyses were conducted and compared to control chickens. In the open-field test, chickens exposed to AFB1 exhibited a reduction in locomotor activity and exploratory behavior. Additionally, AFB1 exposure increased the tonic immobility response. Biochemical analyses revealed that AFB1-contaminated feed reduced whole-brain acetylcholinesterase activity, suggesting impaired cholinergic neurotransmission. Indicators of oxidative stress in the brain revealed a reduction in glutathione levels, superoxide dismutase levels, and total antioxidant capacity, alongside an increase in malondialdehyde levels, indicating heightened oxidative stress in the brain. The neurotoxic effects of AFB1 were further supported by the upregulation of pro-inflammatory cytokine genes, including interleukin-1 beta, interleukin-6, interleukin-17, and inducible nitric oxide synthase, as determined by real-time quantitative polymerase chain reaction. Our study demonstrates that AFB1-contaminated feed influences chicken neurobehavioral outcomes and brain biochemistry and represents the inaugural evidence that AFB1 exposure markedly reduces AChE activity in the whole brain of chickens. Full article

Argentina is among the top consumers of herbicides, yet studies on their environmental and health impact remain scarce. This work aimed to evaluate the effects of herbicide exposure on Pomacea canaliculata as potential biomarkers of contamination. Specifically, we investigated whether paraquat (Pq) and fluroxypyr (Fx) alter enzymatic antioxidant defenses in tissues following acute exposure and induce histological modifications in the digestive gland (DG), particularly in symbiotic corpuscles, after chronic exposure. The nominal no-observed-effect concentration on lethality (NOEC_L) values were 3.62 µg/g dry mass (DM) for Pq and 10.42 µg/g DM for Fx. After acute exposure, superoxide dismutase activity decreased in the DG but increased in the kidney for both herbicides. Catalase activity decreased in the gills but increased in the kidneys of exposed snails, while glutathione-S-transferase activity increased in the DG and kidney after Pq exposure. Following chronic exposure (Pq: 1.45 µg/g DM; Fx: 6.94 µg/g DM), epithelial thickening and vacuolization were observed in Fx-exposed snails. Morphometric analysis of the DG showed that Pq reduced the epithelial occupancy of the symbiont’s vegetative form while increasing its cystic form. These findings indicate that both herbicides impact antioxidant defenses, DG function and host–symbiont interactions, reinforcing the suitability of P. canaliculata as bioindicator organisms. Full article

Exposing insects to mild and/or severe heat can protect them from future heat stress by regulating the expression of certain stress markers. In this study, 60 queen larvae, one day old, were divided into the following two groups: a control group of non-heat-treated mother queens (nH-T MQ) kept for 15 min at 34.5 °C and 70% relative humidity (RH) and a pre-heat-treated mother queen group (pH-T MQ) that was kept for 15 min at 41 °C and 70% RH. Then, 500 daughter workers were collected from brood combs of each group and incubated at room temperature (22 °C) for 30 min, then divided into five groups (n = 100); each group was incubated for one hour at 35, 40, 45, 50, and 55 °C, respectively. The expression levels of several antioxidant genes and markers in 10 workers of each treatment were assessed by relative quantitative Real-Time qPCR and/or ELISA. The pH-T MQ showed improved basal and dynamic expression of several genes and enzymes, which indicated a protective response against heat stress and the effectiveness of tissue hardening on the biological process and/or mechanisms in oxidative stress and antioxidant activity response. These recorded changes may have global implications by improving thermotolerance acquisition during heat stress conditions. Full article

The relationship between various central nervous system (CNS) disorders linked to pesticide exposure highlights a growing concern worldwide, as the extensive use of these compounds causes toxic effects on the CNS of non-target organisms. Reports indicate that exposure to pesticides, including carbamates, organophosphates, and pyrethroids, produces various adverse impacts on neurological function in humans, ranging from acute symptoms such as headaches and dizziness to long-term conditions leading to developmental delays in children, cognitive impairment, and neurodegenerative diseases, such as Parkinson’s and Alzheimer’s being among the most important. The scientific evidence suggests that pesticide exposure induces oxidative stress and disruptions in neurotransmission, resulting in neuronal damage and alterations in brain development. The review discusses scientific evidence of neurodegenerative disease development related to pesticide exposure, as well as alternatives to chemical pesticides used in agriculture, emphasizing Agroecological Crop Protection (ACP), which combines biological control, crop rotation, and natural predators and is presented as a practical approach to reducing reliance on pesticides. Organic farming methods, which employ natural substances and minimal input of chemicals, also offer safer alternatives. In addition, advances in biopesticides, which target specific pests without harming non-target organisms, provide promising solutions that protect the environment and human health. Pesticides are well-known environmental stressors that menace biodiversity and pose important threats to human health. Reducing pesticide use and remediating pesticide-polluted sites are urgent tasks to avoid adverse effects of pesticide exposure in non-target organisms. Full article

Soil microorganisms provide multifaceted benefits, including maintaining soil nutrient dynamics, improving soil structure, and instituting decomposition, all of which are important to soil health. Unpredictable weather events, including flooding from heavy rainfall, flash floods, and seawater intrusion, profoundly impact soil ecology, which is primarily challenged by flooding stress, and imbalances these microbial communities and their functions. This disturbance impairs the symbiotic exchanges between microbes and plants by limiting root exudates and habitats for microbes, as well as nutrient acquisition efficiency for plants. Therefore, this review comprehensively examines the changes in soil microbial communities that occur under flooding conditions. Flooding reduces soil oxygen (O₂) levels, limiting aerobic microbes but promoting anaerobic ones, including potential pathogens. In flooded soil, O₂ deficiency indirectly depends on the size of the soil particles and water turbidity during flooding. O₂ depletion is critical in shaping microbial community adaptation, which is linked to variations in soil pH, nutrient concentrations, and redox status, and fresh and saline water vary differently in terms of the adaptation of microorganisms. Wet soil alters soil enzyme activity, which influences microbial community composition. Notably, three-month post-flooding conditions allow microbial communities to adapt and stabilize more effectively than once-weekly flooding frequency. Based on the presence of aboveground species, fungi are found to reduce under flooding conditions, while nematode numbers, surprisingly, increase. Direct and indirect impacts between soil microbes and physio-chemical properties indicate positive or negative feedback loops that influence the soil ecosystem. Over the years, beneficial microorganisms such as plant-growth-promoting microbes (PGPMs) have been identified as important in regulating soil nutrients and microbial communities in wetland environments, thereby enhancing soil health and promoting better plant growth and development. Overall, understanding the mechanisms of belowground ecosystems under flooding conditions is essential for optimizing agricultural practices and ensuring sustainable crop production in flood-prone areas. Full article

The aim of the present study was to assess heavy metal tolerance and its accumulation potential in coastal nitrophilic species Rumex maritimus, and to study the possible effects of nitrogen fertilizer and salinity on the characteristics of metal-treated plants. Two experiments were performed in partially controlled greenhouse conditions: (1) gradual treatment with increasing concentrations of Cd, Pb, Cu, Mn, and Zn; and (2) acute treatment with Cd, Pb, and Cu on the background of different nitrogen fertilizer amendment rates (0.15 and 0.30 g L⁻¹ N) and salinity (50 and 100 mM). R. maritimus plants were extremely tolerant to treatment with all metals, with no negative effect on total leaf biomass both in the case of gradual or acute treatment. However, the number and biomass of dry leaves increased under high doses of heavy metals, and the effect was more pronounced in the case of acute treatment. All studied metals were excluded from the roots and young leaves, predominantly accumulating in the dry leaves, reaching 250 mg kg⁻¹ for Cd, 2000 mg kg⁻¹ for Pb, and 500 mg kg⁻¹ for Cu. In the second experiment, the presence of increased nitrogen in the substrate positively affected the growth of R. maritimus plants and their morphological response to heavy metals, but salinity affected metal accumulation. Photosynthesis-related parameters, leaf chlorophyll concentration, and the chlorophyll a fluorescence parameter Performance Index Total confirmed that heavy metals had no negative effect on the physiological state of photosynthetically active leaves. It is concluded that R. maritimus plants have exceptional potential for practical phytoremediation needs due to the high tolerance and accumulation potential for heavy metals. Full article