Health Of Organisms Research Articles

Unveiling Aquatic Organism Health Through eProteins: A Contemporary Perspective

Environmental DNA (eDNA) analysis has transformed our understanding of aquatic ecosystems, but traditional methods often lack insights into organismal health. The emerging field of environmental protein (eProtein) analysis offers a novel approach to monitoring the physiological status of aquatic organisms. Recent advancements in proteomic technologies have enabled the detection and characterization of stress-responsive proteins in water samples, providing valuable insights into organismal health and environmental stressors. This perspective paper explores the potential of eProtein analysis for monitoring aquatic organism health, disease dynamics and reproductive cycles. Methodological advancements in protein extraction and mass spectrometry have enhanced the sensitivity and specificity of eProtein analysis, facilitating comprehensive molecular profiling and biomarker identification. By integrating eProtein analysis into aquaculture management and environmental monitoring, researchers can proactively manage fish health, mitigate disease outbreaks and safeguard aquatic ecosystems. Future research directions include refining extraction methods, establishing standardized protocols and leveraging interdisciplinary collaborations to maximize the potential of eProtein analysis for aquatic research and conservation.

Environmental legislation analysis improvement approach of global marine plastic pollution from the perspective of holistic system view

Marine plastic pollution (MPP) has posed an unavoidable challenge to the conservation of marine ecosystems, escalating at an unprecedented rate. It extends beyond visible pollution, infiltrating the food chain and microcirculation, ultimately affecting the life and health of marine organisms. Of even greater concern is the fact that MPP has been found to penetrate human bloodstreams. The international community increasingly focuses on MPP, and has formulated a series of laws and regulations. This article analyses marine pollution prevention legislation within the context of international environmental resolutions and conventions, including those established by the United Nations, the European Union law and the domestic legislation of sovereign states. It is evident that the current legislation has played a pivotal role in the preventing MPP. However, global legislation on preventing MPP remains fragmented. The problems existing in the current legislation should be reviewed from the holistic systems perspective, and the integrity and systematicness of new plastics convention should be demonstrated. The proposed Marine Plastics Convention should emphasize environmental justice, protect the rights of vulnerable populations, lower the threshold for risk prevention, and focus on addressing residual risks. It must include clear provisions for regulating hydrosphere plastic pollution (HPP) to mitigate land-based pollution and scientifically define fundamental legal concepts to foster coordinated action among States. Moreover, the convention should establish standardized monitoring methodologies and assessment criteria to ensure accurate evaluation of the pollution status.

Integration of transcriptomics, gut microbiota, and physiology reveals the toxic response of bensulfuron-methyl in Procambarus clarkii

Bensulfuron-methyl (BSM) enters the environment through agricultural practices, posing a threat to the health of aquatic organisms. Currently, the toxic mechanisms of BSM on crayfish (Procambarus clarkii) have not been thoroughly investigated. In this study, crayfish were exposed to BSM solutions at concentrations of 0, 5, and 10 mg/L for 48 h. The study integrated physiological, gut microbiota, and transcriptomic analyses to investigate the mechanisms of action. BSM exposure induced oxidative stress responses in crayfish, resulting in changes in superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GSH) activity, and malondialdehyde (MDA) levels. Exposure to BSM caused damage to the intestinal tissues, reduced gut microbiota diversity, increased the abundance of harmful bacteria, and led to intestinal dysfunction. Analysis of the hepatopancreas revealed significant tissue damage. Transcriptomic data indicated that BSM affects the growth of crayfish through genes related to immune response (SLC17A5, CTSD, CTSB, NFKBIA, Mincle). The lysosomal pathway and NF-κB pathway were notably affected. This study analyzed the negative impacts of BSM on crayfish from various levels and provided detailed data to enhance our understanding of the toxic mechanisms of BSM in aquatic organisms.

Do cooking techniques influence copper bioaccesibility in foods after in vitro digestion/fermentation in adults and children?

Cu is essential for the growth and organism health. Classically, its available fraction has been studied by in vitro digestion studies as a measure of bioaccessibility of Cu (Cu-BA). In this work we applied a novel in vitro digestion/fermentation method to multiple foods subjected to different home cooking techniques (raw form vs. frying, roasting, toasting, boiling and grilling) by metabolization with faecal inoculate from healthy adults (HE-AD), and healthy children (HE-CH) and sick children (children with gluten related disorders, GRD-CH; children with obesity, OB-CH; and children with allergy/intolerance to cow’s milk proteins, AICM-CH). In raw and cooked foods the bioaccessibility of Cu in the small intestine (Cu-BASI) was higher vs. that in the Cu bioaccessibility in the large intestine (Cu-BALI) (30.8 ± 15.4 and 28.2 ± 14.7 vs. 18.4 ± 21.2 and 22.8 ± 22.1 %, respectively; p < 0.001). Total Cu-BA in cooked foods (51.0 ± 24.4 %) was higher than that in raw foods (49.0 ± 25.1 %). In cereals, total Cu-BA was higher in the raw form, as well as in whole grains and those with gluten (p < 0.05). In vegetables, the most drastic cooking techniques (roasting and frying) show higher values of total Cu-BA compared to raw form and boiling. The Cu-BALI in HE-CH (37.7 ± 23.7 %) is higher than that determined in HE-AD (14.1 ± 18.5 %) and sick children (GRD-CH: 14.6 ± 19.8; OB-CH: 15.5 ± 17.8; and AICM-CH: 26.9 ± 19.3 %; p < 0.001). In conclusion, cooking techniques influence Cu-BA depending on the food group. Total Cu-BA, as well as that determined in the large and small intestine varied according to the category, group and specific foods, which is related to their different composition and species of the element. In healthy children, total Cu-BALI is higher than in adults and celiac, obese and allergic children probably due to growth requirements and specific microbiota.

The mitochondrial long non-coding RNA lncMtloop regulates mitochondrial transcription and suppresses Alzheimer's disease.

Maintaining mitochondrial homeostasis is crucial for cell survival and organismal health, as evidenced by the links between mitochondrial dysfunction and various diseases, including Alzheimer's disease (AD). Here, we report that lncMtDloop, a non-coding RNA of unknown function encoded within the D-loop region of the mitochondrial genome, maintains mitochondrial RNA levels and function with age. lncMtDloop expression is decreased in the brains of both human AD patients and 3xTg AD mouse models. Furthermore, lncMtDloop binds to mitochondrial transcription factor A (TFAM), facilitates TFAM recruitment to mtDNA promoters, and increases mitochondrial transcription. To allow lncMtDloop transport into mitochondria via the PNPASE-dependent trafficking pathway, we fused the 3'UTR localization sequence of mitochondrial ribosomal protein S12 (MRPS12) to its terminal end, generating a specified stem-loop structure. Introducing this allotropic lncMtDloop into AD model mice significantly improved mitochondrial function and morphology, and ameliorated AD-like pathology and behavioral deficits of AD model mice. Taken together, these data provide insights into lncMtDloop as a regulator of mitochondrial transcription and its contribution to Alzheimer's pathogenesis.

Evaluating Water Quality through Macroinvertebrate Diversity and Physicochemical Parameters in the Thamirabarani River Basin

&lt;p style="margin-top:13px; text-align:justify"&gt;&lt;span style="font-size:11pt"&gt;&lt;span style="line-height:115%"&gt;&lt;span style="font-family:Arial,&amp;quot;sans-serif&amp;quot;"&gt;&lt;span lang="EN" style="font-size:12.0pt"&gt;&lt;span style="line-height:115%"&gt;&lt;span style="font-family:&amp;quot;Times New Roman&amp;quot;,&amp;quot;serif&amp;quot;"&gt;Aquatic ecosystems in the Thamirabarani River Basin, Tamil Nadu, India, are facing increasingly complex challenges due to climate change, particularly concerning water temperature and dissolved oxygen levels. This study delves into the intricate relationship between these variables and their profound implications for freshwater biodiversity. The rising temperatures and declining dissolved oxygen levels pose escalating threats to the health of aquatic organisms and the stability of ecosystems. To tackle this issue, a hybrid methodology that integrates remote sensing and field data is proposed to calculate the Water Quality Index (WQI) and comprehensively assess ecosystem health. Remote sensing data offer valuable spatial insights, while field measurements ensure accuracy, resulting in robust findings. The study uncovers a significant negative correlation between water temperature and dissolved oxygen levels, highlighting the adverse effects of warming waters on aquatic habitats. Moreover, habitat fragmentation exacerbates climate stressors, adding further challenges to freshwater biodiversity conservation. The findings underscore the urgent need for conservation and adaptive management strategies, including temperature regulation, riparian vegetation enhancement, nutrient pollution management, and habitat connectivity preservation. By implementing these measures, biodiversity loss in freshwater ecosystems can be minimized, ensuring their resilience in the face of ongoing climate change. &lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

Metabolomics: Implication in cardiovascular research and diseases.

Cellular metabolism influences all aspects of cellular function and is crucial for overall organismal health. Metabolic disorders related to cardiovascular health can lead to cardiovascular diseases (CVDs). Moreover, associated comorbidities may also damage cardiovascular metabolism, exacerbating CVD and perpetuating a vicious cycle. Given the prominent role of metabolic alterations in CVD, metabolomics has emerged as an imperative technique enabling a comprehensive assessment of metabolites and metabolic architecture within the body. Metabolite profile and metabolic pathways help to deepen and broaden our understanding of complex genomic landscape and pathophysiology of CVD. Here in this review, we aim to overview the experimental and clinical applications of metabolomics in pathogenesis, diagnosis, prognosis, and management of various CVD plus future perspectives and limitations.

How SATURN is studying the impact of ship noise on the behaviour, health, energetics, and populations of aquatic organisms

The EU-funded SATURN project contributes to improve our understanding of the effects of ship noise on aquatic animals through several studies. Assessing the effects of underwater noise on aquatic animals is complex due to the diversity of taxa involved, each with their own sound sensitivity in terms of spectral and temporal aspects, as well as behavioural and physiological sensitivity to acoustic disturbances. To conduct exposure experiments on fish and invertebrates that are sensitive to the particle motion component of sound, we have developed innovative laboratory setups. Invertebrates are studied in an AQUAVIB exposure chamber, while migratory fish species are studied in a MIGRADOME swimming tunnel. The project also focuses on three marine mammal species: porpoises, pilot whales, and harbour seals. These species provide broad biological coverage of acoustic specialisations and relevant European habitats. Field data were collected using tags deployed on wild animals and dose-response relationships of marine mammal behaviour and energetics were established as a function of real-world exposure to ship noise. The effects on porpoise population are assessed using the updated DEPONS model. The results of SATURN will be transferred to stakeholders to inform management actions for the mitigation of the effects of acoustic pollution in marine habitats.

Association between Turbot (Scophthalmus maximus) Fish Phenotype and the Post-Larval Bacteriome.

Over the past decade, an increasing number of studies have emphasized the importance of the host microbiome in influencing organismal health and development. Aligned with this understanding, our study aimed to investigate the potential association between the turbot (Scophthalmus maximus) phenotypic traits and the post-larval bacteriome. Turbot post-larvae were sampled from twenty randomly selected production cycles thirty days after hatching (DAH) across multiple post-larval production batches over a three-month period (April to June). Fish were selectively sampled based on five phenotypic traits, namely, normal, large, small, malformed, and depigmented. Our results showed that small-sized post-larvae had significantly higher bacterial phylogenetic diversity in their bacterial communities than all other phenotypes. A more in-depth compositional analysis also revealed specific associations between certain bacterial taxa and fish phenotypes. For example, the genera Aliivibrio and Sulfitobacter were enriched in small-sized post-larvae, while the family Micrococcaceae were predominantly found in larger post-larvae. Furthermore, genus Exiguobacterium was linked to depigmented larvae, and genus Pantoea was more prevalent in normal post-larvae. These observations underscore the importance of further research to understand the roles of these bacterial taxa in larval growth and phenotypic differentiation. Such insights could contribute to developing microbiome modulation strategies, which may enhance turbot post-larval health and quality and improve larviculture production.

Effects of the organochlorine pesticide metabolite p,p’-DDE on the gastrointestinal lipidome in fish: A novel toxicity pathway for a legacy pollutant

Though phased out from use in the United States, environmental contamination by organochlorine pesticides (OCPs) remains a widespread issue, especially around intensive agricultural regions. OCPs, such as dichlorodiphenyltrichloroethane (DDT) and its primary metabolite, dichlorodiphenyldichloroethylene (DDE), have been detected in soils, sediments, surface waters, and biota decades after their discontinued use. As OCPs are persistent and can bioaccumulate in fats, these compounds can transfer and magnify across food webs. Freshwater predatory fish and birds can accumulate high OCP concentrations, leading to a myriad of deleterious impacts on organismal health. Studies have found evidence of reproductive disruption in predatory fish, such as the largemouth bass (LMB; Micropterus salmoides), associated with DDT and DDE exposure. DDE can act through estrogenic pathways and induce the expression of estrogenic signals in male animals; however, the molecular mechanism of disruption is unclear. Recently, metabolomics research has revealed corollary relationships between lipid signals and organic pollutant toxicity. Here, a two-month feeding experiment on LMB was conducted to assess the interactions of DDE (as p,p'-DDE) in food with gut and liver lipid signaling. Targeted lipidomic analysis revealed global alterations in the abundance of tissue lipids, especially cholesteryl esters and phospholipids, in LMB exposed to low levels of p,p'-DDE. Results from these studies indicate that p,p'-DDE may act through disruption of normal lipid homeostasis to cause toxicity in freshwater fish.

Life stage-specific effects of heat stress on spermatogenesis and oogenesis in Drosophila melanogaster.

Biodiversity is increasingly threatened by unpredictable, frequent, and intense climatic events like heatwaves that pose harmful impacts on ectotherms. Beyond the health and survival of organisms, reduced reproductive performance has emerged as a critical fitness consequence of thermal stress induced by high temperatures. Many studies on these effects expose organisms to heat stress during the adult stage or throughout development, often focusing on cumulative effects across life stages, and they tend to examine one or the other sex. This approach may not reflect the short-term nature of many extreme heat events and limits our understanding of stage- and sex-specific fitness consequences in short-lived organisms. To address this gap, we used Drosophila melanogaster to investigate the sex-specific reproductive performance following short heat stress of varying intensity at different developmental stages. We found the thermal sensitivity to be higher in males than females, and to increase toward adult emergence, leading to nearly complete reproductive failure and substantially slowed recovery. These results highlight how even brief bouts of heat stress during a sensitive phase could affect population dynamics and persistence. Our findings also underscore that incorporating both sex and life stage could improve predictions of species persistence.

Stuck in the mangrove mud: The risk of trace element exposure to shore crabs in restored urban mangroves

The restoration of mangroves in urban environments can increase the risk of contaminant exposure and subsequent health effects to resident biota, yet this risk is rarely considered in mangrove restoration programs. Here we assessed the influence of sediment chemistry on contaminant bioaccumulation in shore crabs from restored and natural mangroves in urban environments compared to a reference site. The concentrations of some trace elements were several-fold higher in the sediment and crab tissues of the urban restored site compared to the natural reference site (Cd = 6×, Co = 7×, Cr = 4×, Mn = 30×, and Ni = 18× greater in sediments, while Cd = 4×, Co = 2×, Cr = 2×, Mn = 6×, and Ni = 3× greater in crab tissues). NMR-based metabolomics on crabs revealed higher abundances of proline and glutamate at urban sites, which may be indicative of physiological stress from trace element contamination. Choice experiments were used to test habitat selectivity by crabs from each population, and showed that crabs avoided sediments from the contaminated urban sites. Our results suggest that restoring mangroves in contaminated environments could create ecological sinks, where animals take residence in the new habitat but are exposed to sediment-based contaminants, with potential implications for organism and population health.

The effects of microplastics exposure on quail's hypothalamus: Neurotransmission disturbance, cytokine imbalance and ROS/TGF-β/Akt/FoxO3a signaling disruption

Microplastics (MPs) have become a major focus of environmental toxicology, raising concerns about their potential adverse effects on animal organs and body systems. As these tiny particles infiltrate ecosystems, they may pose risks to the health of organisms across diverse species. In this study, we attempted to examine the neurotoxic effects of MPs exposure on avian hypothalamus by using an animal model-Japanese quail (Coturnix japonica). The quails of 7-day-old were exposed to 0.02 mg/kg, 0.4 mg/kg and 8 mg/kg polystyrene microplastic (PS-MPs) of environmental relevance for 35 days. The results showed PS-MPs exposure did damages to hypothalamic structure characterized by neuron malformation, irregular arrangement and cellular vacuolation after 5-week exposure. PS-MPs exposure also induced Nissl body reduction and dissolution in the hypothalamus. Moreover, the decrease of acetylcholinesterase (AchE) activity and increasing acetylcholine (Ach) indicated that PS-MPs exposure caused hypothalamic neurotransmission disturbance. PS-MPs exposure also led to neuroinflammation by disrupting the balance between proinflammatory and anti-inflammatory cytokines. Moreover, increasing reactive oxygen species (ROS) and malondialdehyde (MDA) generation with reducing antioxidants indicated PS-MPs led to hypothalamic oxidative stress. Additionally, RNA-Seq analysis found that both transforming growth factor-β (TGF-β) signaling and forkhead box O (FoxO) signaling were disturbed in the hypothalamus by PS-MPs exposure. Especially, the increasing ROS led to TGF-β activation and then induced hypothalamic inflammation by nuclear factor κB (NF-κB) activation. The present study concluded that oxidative stress might be an important mechanistic signaling involved in MPs neurotoxicology.

Germline loss diminishes somatic mitochondria but confers preservation of respiratory function during aging and hypothermia.

Reproductive status influences metabolism and health across lifespan in diverse ways and mitochondrial function playing a critical role in mediating this relationship. Using the Caenorhabditis elegans germline ablation model, we investigated the impact of germline stem cell (GSC) loss on mitochondrial dynamics and respiratory function. Our results show that GSC loss reduces mitochondrial volume and respiratory function in young adulthood but preserves mitochondrial activity during aging and upon exposure to hypothermic stress, correlating with enhanced survival. We found that the transcription factor NHR-49/PPARα, but not DAF-16/FOXO3A, was essential for preserving mitochondrial function and hypothermia resistance in these long-lived mutants. Together, these findings reveal the impact of germline signals on somatic mitochondrial health and underscore the intricate relationship between reproductive fitness and organismal health.

Can stable introns and noncoding RNAs be harnessed to improve health through activation of mitohormesis?

Ever since their introduction a decade ago, stable introns, a type of noncoding (nc)RNAs, are found to be key players in different important cellular processes acting through regulation of gene expression and feedback loops to maintain cellular homeostasis. Despite being commonly regarded as useless byproducts, recent studies in yeast suggested that stable introns are essential for cell survivability under starvation. In Drosophila, we found that a stable intron, sisR-1, has a direct effect in regulating mitochondrial dynamics during short-term fasting and subsequently improved overall oocyte quality. We speculated that the beneficial effects implicated by sisR-1 is through the activation of mitohormesis, an interesting phenomenon in mitochondrial biology. Mitohormesis is suggested to improve health span and lifespan of cells and organisms, but the involvement of ncRNAs is not well-documented. Here, we discuss the potential role of sisR-1 and other ncRNAs in activating mitohormesis and the possible applications in improving cellular and organismal health.

Quantitative NMR Analysis of Marine Macroalgae for AGE Inhibition by Methylglyoxal Scavenging.

Reactive carbonyl species (RCS) induce a fundamental form of biological stress that has driven the evolution of diverse mechanisms for minimizing its impact on organismal health. The complications that accompany uncontrolled hyperglycemia exemplify the health implications when RCS stress exceeds the body's capacity to prevent the excessive formation of advanced glycation end-products. Presented here is a novel quantitative NMR (qNMR) technique for evaluating scavengers of the prominent sugar-derived carbonyl methylglyoxal (MGO). This tool was employed to screen the chemical diversity of marine macroalgae extracts, with a focus on species that have a history of consumption by the World's healthiest populations and are subject to global scale aquacultural production. Fucus vesiculosus demonstrated the highest capacity for inhibiting glycation and scavenging MGO. Additionally, the Chondrus cripsus, Gracilaria vermiculophyla, and Gracilaria tikvahiae extracts had a high capacity for scavenging MGO, representing the first report of this activity. This new qNMR methodology presented is highly applicable for screening extracts and compounds from diverse sources, and the results highlight the potential of macroalgae extracts to be employed as RCS and AGE targeting therapeutics and food additives.

Atypical sphingosine-1-phosphate metabolites—biological implications of alkyl chain length

AbstractSphingosine-1-phosphate (S1P) is a bioactive lipid signaling molecule with pleiotropic implications by both auto- and paracrine signaling. Signaling occurs by engaging five G protein-coupled receptors (S1P1-5) or intracellular pathways. While the extensively studied S1P with a chain length of 18 carbon atoms (d18:1 S1P) affects lymphocyte trafficking, immune cell survival and inflammatory responses, the biological implication of atypical S1Ps such as d16:1 or d20:1 remains elusive. As S1P lipids have far-reaching implications in health and disease states in mammalian organisms, the previous contrasting results may be attributed to differences in S1P’s alkyl chain length. Current research is beginning to appreciate these less abundant atypical S1P moieties. This review provides an up-to-date foundation of recent findings on the biological implications of atypical S1P chain lengths and offers a perspective on future research endeavors on S1P alkyl chain length–influenced signaling and its implications for drug discovery.

Impacts of graphene oxide contamination on a food web: Threats to somatic and reproductive health of organisms

Contamination of aquatic food webs with nanomaterials poses a significant ecological and human health challenge. Ingestion of nanomaterials alongside food disrupts digestion and impairs physiological processes, with potential consequences for organism fitness and survival. Complex interactions between nanomaterials and biota further exacerbate the issue, influencing life-history strategies and ecosystem dynamics. Accumulation of nanomaterials within autotrophic and detritus-based food webs raises concerns about biomagnification, especially for top-level consumers and seafood-dependent human populations. Understanding the extent and impact of nanomaterial contamination on aquatic biota is crucial for effective mitigation strategies. To address this challenge, we conducted a comprehensive study evaluating the bioaccumulation effects of graphene oxide (GO), a commonly used nanomaterial, within an aquatic food chain. Using a gnotobiotic freshwater microcosm, we investigated the effects of micro- and nano-scale GO sheets on key organisms: green algae (Chlorella vulgaris), brine shrimp (Artemia salina), and zebrafish (Danio rerio). Two feeding regimes, direct ingestion and trophic transfer, were employed to assess GO uptake and transfer within the food web. Direct exposure involved individual organisms being exposed to either nano- or micro-scale GO sheets, while trophic transfer involved a sequential exposure pathway: algae exposed to GO sheets, artemias feeding on the algae, and zebrafish consuming the artemias. Our study provides critical insights into nanomaterial contamination in aquatic ecosystems. Physicochemical properties of GO sheets, including ζ-potential and dispersion, were influenced by salt culture media, resulting in aggregation under salt conditions. Microscopic imaging confirmed the bioaccumulation of GO sheets within organisms, indicating prolonged exposure and potential long-term effects. Notably, biodistribution analysis in zebrafish demonstrated the penetration of nano-sized GO into the intestinal wall, signifying direct interaction with vital organs. Exposure to GO resulted in increased zebrafish mortality and impaired reproductive performance, particularly through trophic transfer. These findings emphasize the urgent need to address nanomaterial contamination in aquatic food webs to protect ecosystem components and human consumers. Our study highlights the importance of developing effective mitigation strategies to preserve the integrity of aquatic ecosystems, ensure resource sustainability, and safeguard human well-being. In conclusion, our study provides crucial insights into the impact of nanomaterial pollution on aquatic biota. By recognizing the challenges posed by nanomaterial contamination and implementing targeted interventions, we can mitigate the adverse effects, preserving the integrity of aquatic ecosystems and safeguarding human health.

Quantification of persulfidation on specific proteins: are we nearly there yet?

Hydrogen sulfide (H2S) played a pivotal role in the early evolution of life on Earth before the predominance of atmospheric oxygen. The legacy of a persistent role for H2S in life's processes recently emerged through its discovery in modern biochemistry as an endogenous cellular signalling modulator involved in numerous biological processes. One major mechanism through which H2S signals is protein cysteine persulfidation, an oxidative post-translational modification. In recent years, chemoproteomic technologies have been developed to allow the global scanning of protein persulfidation targets in mammalian cells and tissues, providing a powerful tool to elucidate the broader impact of altered H2S in organismal physiological health and human disease states. While hundreds of proteins were confirmed to be persulfidated by global persulfidome methodologies, the targeting of specific proteins of interest and the investigation of further mechanistic studies are still underdeveloped due to a lack of stringent specificity of the methods and the inherent instability of persulfides. This review provides an overview of the processes of endogenous H2S production, oxidation, and signalling and highlights the application and limitations of current persulfidation labelling approaches for investigation of this important evolutionarily conserved biological switch for protein function.

Chronic stress increases adaptive immune response over six weeks in the house sparrow, Passer domesticus

The vertebrate stress response enables an organism to shift energy towards activities that promote immediate survival when facing a threat to homeostasis, but it can also have detrimental effects on organismal health. Acute and chronic stressors generally have contrasting effects on immune responses, but the timeline of this transition between acute and chronic stressors and their effects on immune responses remains unclear. In this study, we investigate changes in immune markers in captive house sparrows (Passer domesticus) after exposure to normal laboratory conditions, an acute stressor, and chronic stressors for 42 days. Specifically, we examined changes in baseline and stress-induced corticosterone concentrations, body condition, heterophil/lymphocyte (H:L) ratio, hemolysis-hemagglutination, and wound healing. We found that individuals exposed to a single acute stressor had significantly higher stress-induced corticosterone concentrations 24 h after stressor exposure, however this effect was reversed after 48 h. Chronic stressor exposure resulted in generally stronger adaptive immune responses, demonstrated by higher baseline and stress-induced lysis, higher baseline hemagglutination, and slower wound healing. Within-trait correlations also increased with chronic stressor exposure, suggesting limitations on phenotypic plasticity. Most of the effects of chronic stressor exposure on immune markers strengthened over the 42 days of the experiment and differences between captivity-only and treatment groups were not apparent until approximately 20 days of chronic stressor exposure. These results highlight the importance of stressor duration in understanding the effects of chronic stressor exposure on immune responses.