H2S promotes a glycometabolism disorder by disturbing the Th1/Th2 balance during LPS-induced inflammation in the skeletal muscles of chickens

Myocardial SERCA2 Protects Against Cardiac Damage and Dysfunction Caused by Inhaled Bromine

Myocardial sarcoendoplasmic reticulum calcium ATPase 2 (SERCA2) activity is critical for heart function. We have demonstrated that inhaled halogen (chlorine or bromine) gases inactivate SERCA2, impair calcium homeostasis, increase proteolysis, and damage the myocardium ultimately leading to cardiac dysfunction. To further elucidate the mechanistic role of SERCA2 in halogen-induced myocardial damage, we used bromine-exposed cardiac-specific SERCA2 knockout (KO) mice [tamoxifen-administered SERCA2 (flox/flox) Tg (αMHC-MerCreMer) mice] and compared them to the oil-administered controls. We performed echocardiography and hemodynamic analysis to investigate cardiac function 24 hours after bromine (600 ppm for 30 minutes) exposure and measured cardiac injury markers in plasma and proteolytic activity in cardiac tissue and performed electron microscopy of the left ventricle (LV). Cardiac-specific SERCA2 knockout mice demonstrated enhanced toxicity to bromine. Bromine exposure increased ultrastructural damage, perturbed LV shape geometry, and demonstrated acutely increased phosphorylation of phospholamban in the KO mice. Bromine-exposed KO mice revealed significantly enhanced mean arterial pressure and sphericity index and decreased LV end diastolic diameter and LV end systolic pressure when compared with the bromine-exposed control FF mice. Strain analysis showed loss of synchronicity, evidenced by an irregular endocardial shape in systole and irregular vector orientation of contractile motion across different segments of the LV in KO mice, both at baseline and after bromine exposure. These studies underscore the critical role of myocardial SERCA2 in preserving cardiac ultrastructure and function during toxic halogen gas exposures. SIGNIFICANCE STATEMENT: Due to their increased industrial production and transportation, halogens such as chlorine and bromine pose an enhanced risk of exposure to the public. Our studies have demonstrated that inhalation of these halogens leads to the inactivation of cardiopulmonary SERCA2 and results in calcium overload. Using cardiac-specific SERCA2 KO mice, these studies further validated the role of SERCA2 in bromine-induced myocardial injury. These studies highlight the increased susceptibility of individuals with pathological loss of cardiac SERCA2 to the effects of bromine.

Recent advances in the application of gasotransmitters in spinal cord injury

Spinal Cord Injury (SCI) is a condition characterized by complete or incomplete motor and sensory impairment, as well as dysfunction of the autonomic nervous system, caused by factors such as trauma, tumors, or inflammation. Current treatment methods primarily include traditional approaches like spinal canal decompression and internal fixation surgery, steroid pulse therapy, as well as newer techniques such as stem cell transplantation and brain-spinal cord interfaces. However, the above methods have limited efficacy in promoting axonal and neuronal regeneration. The challenge in medical research today lies in promoting spinal cord neuron regeneration and regulating the disrupted microenvironment of the spinal cord. Studies have shown that gas molecular therapy is increasingly used in medical research, with gasotransmitters such as hydrogen sulfide, nitric oxide, carbon monoxide, oxygen, and hydrogen exhibiting neuroprotective effects in central nervous system diseases. The gas molecular protect against neuronal death and reshape the microenvironment of spinal cord injuries by regulating oxidative, inflammatory and apoptotic processes. At present, gas therapy mainly relies on inhalation for systemic administration, which cannot effectively enrich and release gas in the spinal cord injury area, making it difficult to achieve the expected effects. With the rapid development of nanotechnology, the use of nanocarriers to achieve targeted enrichment and precise control release of gas at Sites of injury has become one of the emerging research directions in SCI. It has shown promising therapeutic effects in preclinical studies and is expected to bring new hope and opportunities for the treatment of SCI. In this review, we will briefly outline the therapeutic effects and research progress of gasotransmitters and nanogas in the treatment of SCI.

Chlorogenic acid protects against intestinal inflammation and injury by inactivating the mtDNA-cGAS-STING signaling pathway in broilers under necrotic enteritis challenge

This study aimed to determine the effects of chlorogenic acid (CGA) on the growth performance, intestinal health, immune response, and mitochondrial DNA (mtDNA)-cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway in broilers under necrotic enteritis (NE) challenge. The 180 one-day-old male Cobb 500 broilers with similar body weight of 44.59 ± 1.39 g were randomly allocated into 3 groups. The groups were control diet (Control group), control diet + NE challenge (NE group), and control diet + 500 mg/kg CGA + NE challenge (NE + CGA group), with 6 replicates per treatment. All broilers except the Control group were given sporulated coccidian oocysts (d 14) and Clostridium perfringens (d 19-21) by oral gavage. Our findings showed that CGA improved the growth performance and intestinal morphology in broilers under NE challenge. CGA supplementation elevated the barrier function in broilers under NE challenge, which reflected in the decreased serum concentrations of D-lactate and diamine oxidase, and upregulated jejunal protein expression of occludin. CGA supplementation also improved the immune function, which reflected in the increased concentrations and gene expressions of anti-inflammatory factors, and decreased concentrations and gene expressions of proinflammatory factors. CGA supplementation further enhanced intestinal cell proliferation and differentiation, which manifested in the increased number of goblet cells and positive cells of proliferating cell nuclear antigen on d 28 and 42. Furthermore, CGA supplementation decreased the mtDNA (d 42) and mitochondrial reactive oxygen species levels (d 28 and 42), and increased the mitochondrial membrane potential (d 42) and mitochondrial complex I (d 28 and 42) or III (d 28) activity. Broilers challenged with NE had upregulated jejunal protein expressions of cGAS, phospho-TANK-binding kinase 1, and phospho-interferon regulatory factor 7 compared with the Control group, which were downregulated after CGA supplementation. In conclusion, dietary supplementation CGA could protect against intestinal inflammation and injury by reducing the leakage of mtDNA and inactivating the cGAS-STING signaling pathway in broilers under NE challenge.

miR-210/NF-κB axis: A new direction for regulating cadmium-induced pig artery inflammatory injury

Cadmium (Cd) is a toxic metal pollutant that still exists in the environment. The microRNA (miRNA) is a type of noncoding RNA that plays an important role in gene posttranscriptional regulation and disease development. Although the toxic effects of Cd have been extensively studied, studies on the mechanism of Cd from the perspective of miRNA are still limited. So, we established a Cd-exposure pig model, which confirmed that Cd exposure would cause pig artery damage. The miR-210 with the most reduced expression and the nuclear factor kappa B (NF-κB) that had a targeting relationship with miR-210 were screened. The effect of miR-210/NF-κB on the artery damage induced by Cd exposure was investigated by acridine orange/ethidium bromide staining, reactive oxygen species (ROS) staining, quantitative PCR, and western blotting. The results showed that miR-210 inhibitor, pcDNA-NF-κB could induce ROS overproduction in pig hip artery endothelial cells, thus inducing Th1/Th2 imbalance and necroptosis, leading to increased inflammation, while small interfering RNA-NF-κB played a mitigating role. In conclusion, Cd can induce artery necroptosis and Th1/Th2 imbalance by regulating the miR-210/NF-κB axis, so as to lead to artery inflammatory damage. In this study, we explored the way in which Cd exposure causes artery damage in pig, providing a new perspective on the regulatory damage of miR-210/NF-κB axis.

Chlorpyrifos exposure induces calcium-dependent necrosis in carp (Cyprinus carpio) lymphocytes via the inhibition of T cell receptor gamma (TCR γ)

The insecticide chlorpyrifos plays an important role in agricultural production and is widely used because of its excellent insecticidal ability. However, the mechanism by which chlorpyrifos causes lymphocyte death remains unclear. In this study, transcriptomic techniques were used to analyze the head kidney tissues of carp (Cyprinus carpio) treated with chlorpyrifos. Subsequently, we screened out differentially expressed genes (DEGs) and performed the corresponding processing in the head kidney lymphocyte. Then, the intracellular calcium content and necrosis were detected by fluorescence staining, real-time fluorescence quantitative PCR, and flow cytometry. Our results showed that the expression of T cell receptor gamma (TCR γ) was significantly decreased, and TCR γ was inhibited after chlorpyrifos treatment. Also, TCR γ significantly increased the abundance of calcium channel messenger RNA (mRNA). To verify this result, we established the TCR γ overexpression group and found that the reverse results were observed in TCR γ of in the overexpression group. The results of cytoplasmic calcium concentration detection, calcium staining, and flow cytometry confirmed the conclusion of increased calcium in the cytoplasm. The function of TCR γ significantly enhanced the mRNA expression levels of necrosis-related genes, and this conclusion was evidenced by the result of necrotic flow detection. Our results showed that chlorpyrifos could inhibit TCR γ in carp lymphocytes and induce calcium-dependent necrosis.

Development of an activatable hydrogen sulfide-specific two-photon fluorescent probe for bioimaging in an air pouch inflammation model

Inflammation caused by traumatic, ischemic, infectious, autoimmune or toxic injury may further trigger cancer and even death. Overexpression of hydrogen sulfide (H₂S) in vivo has been identified as a biomarker for various types of inflammation. Identification-responsive fluorescence imaging probes have broad application prospects for in vivo diagnosis of inflammation. However, it is a challenge to design an imaging probe that concurrently responds to the target molecules to improve the sensitivity and specificity of inflammation detection. Herein, we designed and synthesized an activatable two-photon fluorescent probe to detect H₂S. Fl-H2S had high selectivity, excellent photostable signals and low detection limit for recognizing H₂S. In addition, Fl-H2S showed excellent two-photon fluorescence properties in cell and liver tissue visualization experiments, with a penetration depth of up to 126 μm in liver tissue. Most importantly, the unique probe Fl-H2S was the first probe to monitor H₂S levels in a mouse air pouch inflammation model by fluorescence imaging technology. We expect Fl-H2S to become an effective tool for longitudinal monitoring of inflammation, diagnosis of inflammation and prediction of underlying pathogenesis of related diseases by detecting H₂S.

Subacute cadmium exposure modulates Th1 polarization to trigger ER stress-induced porcine hepatocyte apoptosis via regulation of miR-369-TNFα axis

Cadmium (Cd), as a common environmental pollutant, has been reported to cause T lymphocyte dysfunction and cell apoptosis in multiple organs. However, whether subacute Cd exposure can induce apoptosis of hepatocytes and the relationship with Th1/Th2 imbalance were still unclear. In this study, ten 6-week-old piglets were selected and randomly assigned into two groups, the control group and the Cd group. The control group was fed with the standard diet, and for the Cd group, the standard diet was supplemented with 20 mg/kg CdCl2; liver tissue was collected on the 40th day of the experiment. Immunofluorescence, qRT-PCR, and western blot were performed to detect the expression of miR-369, Th1/Th2 biomarkers, endoplasmic reticulum (ER) stress-related genes, and apoptotic genes. TUNEL assay was applied to stain apoptotic hepatocytes. In the Cd group, the apoptosis of hepatocytes was significantly increased, and associated with the declined expression of miR-369, Th1 polarization, the elevated expression of ER stress pathway genes and their downstream pro-apoptosis genes, and downregulated expression of anti-apoptotic genes. These results manifest that subacute Cd exposure mediates Th1 polarization to promote ER stress-induced porcine hepatocyte apoptosis via regulating miR-369-TNFα. These results not only provide a basis for the enrichment of Cd toxicology but also support a theoretical foundation for the prevention and therapy of Cd poisoning. Schematic diagram illustrating the proposed mechanism of subacute cadmium exposure modulates Th1 polarization to trigger ER stress-induced porcine hepatocyte apoptosis via regulation of miR-369-TNFα axis.

Buffering Adaptive Immunity by Hydrogen Sulfide

T cell-mediated adaptive immunity is designed to respond to non-self antigens and pathogens through the activation and proliferation of various T cell populations. T helper 1 (Th1), Th2, Th17 and Treg cells finely orchestrate cellular responses through a plethora of paracrine and autocrine stimuli that include cytokines, autacoids, and hormones. Hydrogen sulfide (H₂S) is one of these mediators able to induce/inhibit immunological responses, playing a role in inflammatory and autoimmune diseases, neurological disorders, asthma, acute pancreatitis, and sepsis. Both endogenous and exogenous H₂S modulate numerous important cell signaling pathways. In monocytes, polymorphonuclear, and T cells H₂S impacts on activation, survival, proliferation, polarization, adhesion pathways, and modulates cytokine production and sensitivity to chemokines. Here, we offer a comprehensive review on the role of H₂S as a natural buffer able to maintain over time a functional balance between Th1, Th2, Th17 and Treg immunological responses.

Polystyrene microplastics-induced ROS overproduction disrupts the skeletal muscle regeneration by converting myoblasts into adipocytes

The environmental problem of Microplastics (MPs) pollution poses a great threat to human and animal health, which has attracted global attention. The physiological integrity of skeletal muscle is extremely important for the survival of animals. Here, we investigated the effect of two size polystyrene microplastics (PS-MPs, 1-10 µm and 50-100 µm) on the growth of anterior tibial (TA) muscle and repair after injury in mice. Results showed that the regeneration of skeletal muscle was delayed by PS-MPs exposure and was negatively correlated with particle size. H&E staining and Oil red O staining showed that PS-MPs exposure reduced the average cross-sectional area (CSA) and diameter of the muscle fibers, increased lipid deposition. Further mechanistic research displayed that though PS-MPs treatment did not affect cell viability of myoblast, it aggravated intracellular ROS generation and oxidative stress, inhibited myogenic differentiation by decreasing the phosphorylation of p38 MAPK, and promote adipogenic differentiation by increasing the expression of NF-κB, which could be alleviated by NAC. In brief, our data demonstrated that the ROS overproduction caused by PS-MPs disturbed the regeneration of skeletal muscle and directed the fate of satellite cells in mice.

Environmentally relevant concentration of sulfamethoxazole-induced oxidative stress-cascaded damages in the intestine of grass carp and the therapeutic application of exogenous lycopene

Due to the unreasonable use and discharge of the aquaculture industry, over standard of the antibiotics has been frequent in different types of water environments, causing adverse effects on aquatic organisms. Lycopene (LYC) is an esculent carotenoid, which is considered to be a strong antioxidant. This study was designed to explore the therapeutic effect of LYC on antibiotic (sulfamethoxazole (SMZ)) induced intestinal injury in grass carp Ctenopharyngodon idella. The 120 carps (the control, LYC, SMZ, and co-administration groups) were treated for 30 days. We found that treatment with LYC significantly suppressed SMZ-induced intestinal epithelial cell damage and tight junction protein destruction through histopathological observation, transmission electron microscopy and detection of related genes (Claudin-1/3/4, Occludin and zonula occludens (ZO)-1/2). Furthermore, LYC mitigated SMZ-induced dysregulation of oxidative stress markers, including elevated malondialdehyde (MDA) levels, and consumed super oxide dimutese (SOD), catalase (CAT) activities and glutathione (GSH) content. In the same treatment, LYC reduced inflammation and apoptosis by a detectable change in pro-inflammatory factors (tumor necrosis factor-alpha (TNF-β), interleukin (IL)-1β, IL-6 and IL-8), anti-inflammatory factors (transforming growth factor-beta (TGF-β) and IL-10) and pro-apoptosis related genes (p53, p53 upregulated modulator of apoptosis (PUMA), Bax/Bcl-2 ratio, caspase-3/9). In addition, activation of autophagy (as indicated by increased autophagy-related genes through AMPK/ATK/MTOR signaling pathway) under the stress of SMZ was also dropped back to the original levels by LYC co-administration. Collectively, our findings identified that LYC can serve as a protectant agent against SMZ-induced intestinal injury.

Environmentally relevant concentration of cypermethrin or/and sulfamethoxazole induce neurotoxicity of grass carp: Involvement of blood-brain barrier, oxidative stress and apoptosis

In water environment, the interaction between environmental pollutants is very complex, among which pesticides and antibiotics are dominant. However, most studies only focus on individual toxic effects, rather combined. In this study, the sub-chronic exposure effect of cypermethrin (CMN, 0.65 μg/L), sulfamethoxazole (SMZ, 0.30 μg/L) and their mixture on grass crap (Ctenopharyngodon idellus) was investigated. The brain tight junction, oxidative stress and apoptosis-related indices were determined after 42 days of exposure. In terms of brain function, acetyl cholinesterase (AChE) activity was significantly inhibited by CMN, SMZ and their mixtures during exposure periods. Obvious histological damage from cellular and subcellular levels were also observed, which were further confirmed by a decrease in tight junction protein levels. Malondialdehyde (MDA) and 8-hydroxy-2-deoxyguanosine (8-OHdG) contents were significantly increased by individual compounds and mixtures, in which the content of glutathione (GSH) displayed the opposite trend. In mechanism, nuclear factor (erythrocyte derived 2) like 2(Nrf2) pathway was activated, which may trigger cellular protection to cope with CMN and SMZ exposure. However, apoptosis was also detected from the level of mRNA and histochemistry. In general, these two exogenous induced similar biological responses. The neurotoxicity of CMN was strengthened by SMZ with regard to these indices in most cases and vice versa. This study will reveal the potential co-ecological risks of pesticide and antibiotic in the aquatic organism, and provide basic data for their safety and risk assessment.

Arsenite induce neurotoxicity of common carp: Involvement of blood brain barrier, apoptosis and autophagy, and subsequently relieved by zinc (Ⅱ) supplementation

Arsenic pollution is a common threat to aquatic ecosystems. The effects of chronic exposure to arsenite on the brains of aquatic organisms are unknown. This study was designed to evaluate arsenic-induced brain damage in common carp (Cyprinus carpio) and the ameliorating effects of divalent zinc ion (Zn2+) supplementation from the aspects of oxidative stress (OxS), tight junction (TJ), apoptosis and autophagy. After arsenite exposure (2.83 mg/L) for 30 days, oxidative damage to the brain was determined, as indicated by inhibited antioxidants system (catalase-superoxide dismutase system, and glutathione system) and elevated levels of biomacromolecule peroxidation (malondialdehyde and 8-hydroxydeoxyguanosine). Moreover, we also found functional damage to the brain as suggested by injuries to the blood-brain barrier (decreases in tight junction) and nerve conduction (depletion of AChE). Mechanisticly, apoptotic and autophagic cell death were indicated by typical morphologies including karyopyknosis and autophagosome, accompanying by key bio-indicators (Bcl-2, caspase and autophagy related gene family proteins). In contrast, the coadministration of Zn2+ (1 mg/L) with arsenite effectively alleviated this damage as suggested by the recovery of the aforementioned bioindicators. This study provides new insight into the brain toxicity caused by arsenite and suggests the application of zinc preparations in the aquatic pollution of arsenic.

Keap1-Nrf2 pathway up-regulation via hydrogen sulfide mitigates polystyrene microplastics induced-hepatotoxic effects

Microplastics, which are new types of environmental pollutants, are recently receiving widespread attention worldwide. Hydrogen sulfide (H₂S) as the third endogenous gaseous mediator had protective effects in multiple physiological and pathological conditions. However, the protective role of H₂S in microplastics-induced hepatotoxocity remain unclear. In this study, our data showed that H₂S significantly suppressed inflammation, apoptosis and oxidative stress induced by polystyrene microplastics (mic-PS) (20 mg/kg b.w.) in the liver. Strikingly, although mic-PS exposure increased the expression of nuclear factor-E2-related factor (Nrf2), it did not influence the levels of heme oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQOl) in the L02 hepatocytes. Immunofluorescence assay showed that sodium hydrosulfide (NaHS) reduced micro-Ps-induced hepatic apoptosis by facilitating nuclear accumulation of Nrf2. Simultaneously, flow cytometry also showed that NaHS could prevent mic-PS-induced accumulation of reactive oxygen species (ROS) by increasing the expression of HO-1 and NQO1. Furthermore, inhibition of HO-1 could reverse the hepatic protective effects of NaHS during mic-PS exposure. Mechanistically, H₂S elevating the HO-1 and NQO1 expression by facilitating nuclear accumulation of Nrf2, and consequently reducing mic-PS-induced hepatic apoptosis and inflammation. This study unveils the hepatotoxic effects of MPs and suggest NaHS have protective effects on mic-PS-induced liver damage.

Curcumin ameliorates mercuric chloride-induced liver injury via modulating cytochrome P450 signaling and Nrf2/HO-1 pathway

Environmental mercury is a concern for coastal ecosystem health, and exerts adverse effects on human health. Despite the growing body of evidence showing the hepatoprotective roles of curcumin on mercury, the knowledge between the macroscopic descriptions and the actual mechanism(s) underlying these processes is getting larger remains elusive. Herein, mice received single injection of mercuric chloride (HgCl₂) (5 mg/kg body weight) and/or curcumin (50 mg/kg, body weight, p.o.). Firstly, the results showed curcumin could decline HgCl₂-induced up-regulated the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Additionally, we also found that curcumin could suppress inflammatory damage, unbalance of trace elements (including sodium, magnesium, kalium, calcium overload), oxidative burst induced by HgCl₂, which could be associated with cytochrome P450 (CYP450) signaling. Secondly, we found that curcumin could prevent HgCl₂-induced cell death both in vivo and in vitro. Furthermore, curcumin significantly increased the nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) and consequently upregulated the expression of heme oxygenase 1 (HO-1) under HgCl₂ treatment. Meanwhile, inhibition of HO-1 by zinc protoporphyria could abolish the cytoprotective effects of curcumin in HgCl₂-treated L02 hepatocytes. In conclusion, our data identify that curcumin could enhance Nrf2-mediated HO-1 to upregulate antioxidant ability, which might be associate with CYP450 signaling to suppress liver damage induced by HgCl₂. The present study further enriches and perfects the mechanism theory of HgCl₂ toxicity and suggest that the CYP450 signaling and Nrf2/HO-1 pathway is important in shedding light on curcumin's hepatoprotective effects in HgCl₂ toxicity.

Grass carps co-exposed to environmentally relevant concentrations of cypermethrin and sulfamethoxazole bear immunodeficiency and are vulnerable to subsequent Aeromonas hydrophila infection

The aquatic ecosystem is seriously damaged because of the heavy use of pesticides and antibiotics. Fish is the indispensable link between environmental pollution and human health. However, the toxic effects of environment-related concentrations of pesticides and antibiotics in fish have not been thoroughly studied. In this study, grass carps exposed to cypermethrin (CMN, 0.651 μg/L) or/and sulfamethoxazole (SMZ, 0.3 μg/L) for 42 days caused oxidative stress, apoptosis and immunodeficiency in the spleen of grass carps. CMN or/and SMZ exposure led to oxidative damage (consumption of antioxidant enzymes (superoxide dismutase and catalase)) and lipid peroxidation (accumulation of malondialdehyde), induced apoptosis (increases in TUNEL index, Bax/bcl-2, p53, puma and Caspase family expression). In addition, the levels of immunoglobulin M (IgM), complement 3 (C3) were significantly decreased in all treatment groups, which trend was also found in C-reactive protein in CMN and MIX group, and lysozyme in MIX group. Transcription of almost all genes involved in the Toll-like receptors (TLR) signaling pathway was up-regulated under CMN or/and SMZ exposure. However, when subsequently attacked by Aeromonas hydrophila for 2 days, the TLR pathway was inhibited in spleens of all treatment groups accompanied by higher mortality. Overall, the environmentally relevant concentration of CMN and SMZ damages the immune system, triggering oxidative stress and apoptosis in carps. And by affecting the conduction of TLR signaling pathway, CMN or/and SMZ exposure inhibits the innate immune response of fish and reducing their disease resistance. This study highlights the importance of rational and regulated use of these pesticides and antibiotics.

The proteomic profiling of multiple tissue damage in chickens for a selenium deficiency biomarker discovery

Over the past decades, substantial advances have been made in both the early diagnosis and accurate prognosis of numerous cancers because of the impressive development of novel proteomic strategies. Selenium (Se) is an essential trace element in humans and animals. Se deficiency could lead to Keshan disease in humans, mulberry heart disease in pigs and damage of tissues including cardiac injury, apoptosis in the liver, reduction in the immune responses in spleen and cerebral lesions in chickens. However, it is well know that plasma biomarkers are not specific and also show alterations in various diseases including those caused by Se deficiency. Therefore, new definition biomarkers are needed to improve disease surveillance and reduce unnecessary chicken losses due to Se deficiency. To identify new biomarkers for Se deficiency, we performed exploratory heart, liver, spleen, muscle, vein, and artery proteomic screens to further validate the biomarkers using Venn analysis, GO enrichment, heatmap analysis, and IPA analysis. Based on the bioinformatics methods mentioned above, we found that differentially expressed genes and proteins are enriched to the PI3K/AKT/mTOR signal pathway and insulin pathway. We further used western blot to detect the expression of proteins related to the two pathways. Results showed that the components of the PI3K/AKT/mTOR signal pathway were definitely decreased in heart, liver, spleen, muscle, vein and artery tissues in the Se deficient group. Expression IGF and IGFBP2 of the insulin pathway were differentially increased in the heart, liver, and spleen in Se deficient group samples and decreased in muscle and artery. In conclusion, 5 proteins, namely PI3K, AKT, mTOR, IGF, and IGFBP2, were differentially expressed, which could be potentially useful Se deficient biomarkers. In the present study, proteomic profiling was used to elucidate protein biomarkers that distinguished Se deficient samples from the controls, which might provide a new direction for the diagnosis and targeted treatment induced by Se deficiency in chickens.

Selenoprotein Gpx3 knockdown induces myocardial damage through Ca2+ leaks in chickens

Glutathione peroxidase 3 (Gpx3) is a pivotal selenoprotein that acts as an antioxidant. However, the role of Gpx3 in maintaining the normal metabolism of cardiomyocytes remains to be elucidated in more detail. Herein, we employed a model of Gpx3 interference in chicken embryos in vivo and Gpx3 knockdown chicken cardiomyocytes in vitro. Real-time PCR, western blotting and fluorescent staining were performed to detect reactive oxygen species (ROS), the calcium (Ca²⁺) concentration, endoplasmic reticulum (ER) stress, myocardial contraction, inflammation and heat shock proteins (HSPs). Our results revealed that Gpx3 suppression increased the level of ROS, which induced Ca²⁺ leakage in the cytoplasm by blocking the expression of Ca²⁺ channels. The imbalance of Ca²⁺ homeostasis triggered ER stress and blocked myocardial contraction. Furthermore, we found that Ca²⁺ imbalance in the cytoplasm induced severe inflammation, and HSPs might play a protective role throughout these processes. In conclusion, Gpx3 suppression induces myocardial damage through the activation of Ca²⁺-dependent ER stress.

MiR-196-5p involvement in selenium deficiency-induced immune damage via targeting of NFκBIA in the chicken trachea

Dietary selenium (Se) deficiency can induce multifarious immune injury in tissues, accompanied by inflammation and a decreased expression of selenoproteins. The results of previous studies indicated that these issues are associated with Se-mediated microRNAs involved in immune regulation, although the specific mechanisms associated with these interactions have not been reported in the trachea of chickens. To explore the effects of Se deficiency in the trachea of chickens and the role of miR-196-5p, we established correlational models of tracheal injury in chickens. One hundred broilers were divided into four groups, including a control group (C group), a Se deficient group (L group), a lipopolysaccharide (LPS)-induced control group (C + LPS group) and a LPS-induced Se deficient group (L + LPS group). Light microscopy observations indicated that the infiltration of inflammatory cells was the major histopathological change caused by Se deficiency. Furthermore, ultrastructural observation of the tracheal epithelium and ciliary showed typical inflammatory signs owing to Se deficiency. We determined the targeting relationship between miR-196-5p and NFκBIA by bioinformatics analysis. In the case of Se deficiency, the changes were detected as follows: 19 selenoproteins showed different degrees of decrease (p < 0.05). Significant inhibition of both antimicrobial peptides and immunoglobulin production were observed (p < 0.05). IκB-α (NFκBIA) expression degraded with the increasing miR-196-5p (p < 0.05), and the NF-κB pathway was activated. Thereafter, we can see a significant increase in the mRNA levels of inflammatory cytokines-related genes (tumor necrosis factor (TNF)-α, inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, prostaglandin E (PTGE), interleukin (IL)-1β, IL-6) and protein expression of NF-κB/iNOS pathway-related genes (NF-κB, iNOS, TNF-α, COX-2) (p < 0.05). The release of IL-2, interferon (IFN)-γ inhibited (p < 0.05) and the secretion of IL-4, IL-6 increased, suggesting the imbalance of Th1/Th2 (Th, helper T cell) cytokines. Compared to the control, the mRNA and protein expression levels of the anti-inflammatory system components with antioxidant activity (PPAR-γ/HO-1) were in an inhibitory state (p < 0.05). Antioxidases (SOD, CAT, GSH-Px) activities were suppressed. The activities of the peroxide markers (MDA, H₂O₂) were enhanced (p < 0.05). In addition, Se deficiency had a positive effect on the pathological changes of inflammation and the exceptional immunity in LPS-treated groups (p < 0.05). The results confirmed the relationship between miR-196-5p and NFκBIA in chickens, revealing that Se deficiency causes respiratory mucosal immune dysfunction via the miR-196-5p-NFκBIA axis, oxidative stress and inflammation. Moreover, Se deficiency exacerbates the inflammatory damage stimulated by LPS. Our work provides a theoretical basis for the prevention of tracheal injury owing to Se deficiency and can be used as a reference for comparative medicine. Furthermore, the targeted regulation of miR-196-5p and NFκBIA may contribute to the protection of the tracheal mucosa in chickens.

Zinc exerts its renal protection effect on arsenic-exposed common carp: A signaling network comprising Nrf2, NF-κB and MAPK pathways

Epidemiological and laboratory investigations have extensively indicated that arsenic exposure accounts for several kidney diseases. Zinc has been suggested as a possible natural preventive and therapeutic agent. This study is designed to explore the beneficial effect of zinc supplementation against arsenic-induced renal toxicity in common carp, and the results point to signaling pathway possibly compromised. In the present study, renal injury was induced in common carp by waterborne exposure to arsenic (2.83 mg/L) for 30 days, and zinc (1 mg/L) was simultaneously supplemented. First, the arsenic-exposed fish showed histological and functional renal alterations (indicated by hematoxylin-eosin staining, biochemical indexes and a TUNEL assay). Moreover, as a reactive oxygen species (ROS) stimulant, arsenic was found to induce oxidative toxicity as determined by increased renal ROS, malondialdehyde, protein carbonyl and 8-hydroxydeoxyguanosine levels. When antioxidant-mediation attempts (through superoxide dismutase and glutathione)-mediated to restore homeostasis failed and ROS increased to extreme levels, inflammation (indicated by elevated inducible nitric oxide synthetase, tumor necrosis factor-alpha and interleukins levels) and apoptosis (through both mitochondrial- and death receptor-dependent pathways) were triggered. However, abnormalities in the upstream mediators Nrf2, NF-κB and MAPK were significantly ameliorated and blocked by treatment with zinc. In conclusion, zinc exerts a substantial protective effect against arsenic-triggered subchronic renal injury in common carp via the amelioration of oxidative stress, suppression of apoptosis and reduced inflammation through Nrf2, NF-κB and MAPK signaling.

Hydrogen sulfide: An endogenous regulator of the immune system

Hydrogen sulfide (H₂S) is now recognized as an endogenous signaling gasotransmitter in mammals. It is produced by mammalian cells and tissues by various enzymes - predominantly cystathionine β-synthase (CBS), cystathionine γ-lyase (CSE) and 3-mercaptopyruvate sulfurtransferase (3-MST) - but part of the H₂S is produced by the intestinal microbiota (colonic H₂S-producing bacteria). Here we summarize the available information on the production and functional role of H₂S in the various cell types typically associated with innate immunity (neutrophils, macrophages, dendritic cells, natural killer cells, mast cells, basophils, eosinophils) and adaptive immunity (T and B lymphocytes) under normal conditions and as it relates to the development of various inflammatory and immune diseases. Special attention is paid to the physiological and the pathophysiological aspects of the oral cavity and the colon, where the immune cells and the parenchymal cells are exposed to a special "H₂S environment" due to bacterial H₂S production. H₂S has many cellular and molecular targets. Immune cells are "surrounded" by a "cloud" of H₂S, as a result of endogenous H₂S production and exogenous production from the surrounding parenchymal cells, which, in turn, importantly regulates their viability and function. Downregulation of endogenous H₂S producing enzymes in various diseases, or genetic defects in H₂S biosynthetic enzyme systems either lead to the development of spontaneous autoimmune disease or accelerate the onset and worsen the severity of various immune-mediated diseases (e.g. autoimmune rheumatoid arthritis or asthma). Low, regulated amounts of H₂S, when therapeutically delivered by small molecule donors, improve the function of various immune cells, and protect them against dysfunction induced by various noxious stimuli (e.g. reactive oxygen species or oxidized LDL). These effects of H₂S contribute to the maintenance of immune functions, can stimulate antimicrobial defenses and can exert anti-inflammatory therapeutic effects in various diseases.

Dysfunction of thioredoxin triggers inflammation through activation of autophagy in chicken cardiomyocytes

Thioredoxin (Txn) is a hydrogen carrier protein and exists widely in organism. Txn deficiency implicates cardiomyocytes injury has been proven. However, the exact mechanism remains unclear. To understand the mechanistic response of cardiomyocytes subsequent to Txn suppression, we established the model of Txn dysfunction by employing gene interference technology (siRNA) and Txn inhibitor (PX-12) in cardiomyocytes. We detected the ROS levels, inflammation factors, and key proteins in the autophagy and apoptosis. In addition, heat map was used for further analysis. Our results revealed that Txn dysfunction increased the release of ROS and induced activation of autophagy via upregulation of Becline-1, LC3-1, 2, which further regulated the inflammatory response, meanwhile, Txn silence inhibited apoptosis in chicken cardiomyocytes through Caspase-3 inhibition. Altogether we concluded that Txn-deficient chicken cardiomyocytes experienced autophagy, which caused severe inflammatory reactions and resulting in damage to cardiomyocytes.

Selenium Deficiency Induces Inflammation via the iNOS/NF-κB Pathway in the Brain of Pigs

Selenium (Se) is an essential trace element to maintain homeostasis in humans and animals. The aim of the present study was to clarify the mechanism of Se deficiency-induced inflammation in the pig's brain. Twenty-four healthy pigs were randomly divided into two groups (n = 12/group): control group (group C) was fed diet with 0.3 mg/kg inorganic Se, and Se-deficient group (group L) was fed diet with 0.007 mg/kg inorganic Se. At the 90th day of the experiment, the histology in the pig's brain was observed by the microscope, the NO levels and iNOS activity were assayed, and the mRNA and protein expression levels of inflammatory cytokines (iNOS, COX-2, NF-κB, and PTGEs) and HSPs (HSP27, HSP40, HSP60, HSP70, and HSP90) were detected by real-time quantitative PCR and Western blot. Compared with group C, both of NO levels and iNOS activity were increased in group L, and the mRNA and protein expression levels of inflammatory cytokines (iNOS, COX-2, NF-κB, and PTGEs) and HSPs (HSP27, HSP40, HSP60, HSP70, and HSP90) were also upregulated; histological observation displayed inflammatory response in the brain of pig. In summary, diet with Se deficiency can activate the iNOS/NF-κB pathway to upregulate the expression of inflammatory cytokines, thereby leading to inflammatory lesions in the pig's brain, and HSPs are involved in the compensatory regulation of inflammation. This study provides a reference for the prevention of pig brain inflammation from the perspective of nutrition.

Transcriptome analysis of Takifugu obscurus liver in response to acute retene exposure

Retene (1-methyl-7-isopropyl-phenanthrene, RET) is an alkyl polycyclic aromatic hydrocarbon (PAH) with environmental risk to aquatic animals. Takifugu obscurus is a migratory fish species with high economic and ecological value. To assess the toxic effects of RET on molecular metabolism, juvenile T. obscurus in this study were acutely exposed to 44.30 µg/L of RET for four days. The transcriptome profiles of livers were compared between RET treatment group and the control, and the results revealed that 1,897 genes were significantly differentially expressed (DEGs) after exposure to RET, which enriched 17 KEGG pathways. Among these, glycerolipid metabolism, glycerophospholipid metabolism, insulin signaling pathway, and FOXO signaling pathways were significantly activated. Further exploration indicated that RET exposure disrupted glucose metabolism, stimulated insulin metabolism, and activated cell proliferation genes. Overall, these findings help explain the molecular mechanisms underlying RET toxicity, and may offer evidence to support T. obscurus protection.

Selenium deficiency induced necroptosis, Th1/Th2 imbalance, and inflammatory responses in swine ileum

Selenium (Se) deficiency has a significant impact on the swine breeding industry by inducing digestive system damage and diarrhea. However, the molecular mechanism remains unclear. Our objectives were to investigate if different amounts of necroptosis, inflammatory responses, and T helper cell 1/T helper cell 2 (Th1/Th2) imbalances were induced by Se deficiency in intestinal porcine jejunal epithelial cells (IPEC-J2) and swine ileum tissue. Therefore, Se-deficient models were successfully established both in vitro and in vivo. In the current study, the cell morphological observation results showed that Se deficiency seriously affected the growth and differentiation of IPEC-J2 cells. Moreover, the necroptosis staining and histomorphology observation results showed that the number of necroptotic cells increased significantly, and the ileal tissue exhibited abnormal structures, including necroptotic features and inflammatory cell infiltration, in the Se-deficient group. Furthermore, Se deficiency resulted in accelerated cell necroptosis by increasing (p < .05) the expression of genes related to the tumor necrosis factor-α pathway at both the protein and messenger RNA (mRNA) levels compared to the control group. Moreover, the relative mRNA and protein expression of the inflammatory genes and their responses to dietary Se deficiency were consistent with the resultant Th1/Th2 imbalances in vitro and in vivo. Taken together, the results suggested that Se deficiency caused necroptosis, inflammatory responses, and abnormal expression of cytokines in swine ileum tissue. These findings might help us to explain the damage induced by Se deficiency to the digestive system of swine.

Glyphosate induces lymphocyte cell dysfunction and apoptosis via regulation of miR-203 targeting of PIK3R1 in common carp (Cyprinus carpio L.)

Glyphosate is a widely used pesticide worldwide. The problem surrounding glyphosate is worth investigating, especially with its increased use, and an increasing number of studies have found that the toxic effect of glyphosate is objective. MiR-203 was seldom found in fish diseases or glyphosate researches. This article aims to explore the effect of miR-203 on carp lymphocytes during glyphosate exposure. Therefore, acridine orange/ethidium bromide (AO/EB) and flow cytometry were carried out to evaluate apoptosis, and we also detected CYPs (CYP1A1, CYP1B1, CYP1C), cytokine secretion (IL-1β, IL-8, IL-10, IFN-γ, TNF-α), inflammatory factors (NF-κB, cox-2), and the expression of miR-203 and the PI3K/AKT pathway by RT-PCR and Western blot analyses. Our results demonstrated that glyphosate exposure could induce lymphocyte apoptosis via regulation of miR-203 targeting of PI3K/AKT, which was accompanied by CYPs activation, abnormal cytokine expression and an inflammatory response. These results show that glyphosate is not nontoxic to fish and provide new insights for the usage of glyphosate as an herbicide in the future.

MicroRNA profiling identifies biomarkers in head kidneys of common carp exposed to cadmium

Cadmium (Cd) is an increasingly important environmental pollutant due to its high toxicity to fish and aquatic animals. In the present study, we cultured common carp (Cyprinus carpio L.) in two groups, a control group and a Cd group, with the Cd group being exposed to Cd for 30 d. The antioxidant enzyme activities of T-AOC and CAT and the GSH content were differentially decreased during Cd exposure. miRNAome profiling indicated that 23 differentially expressed miRNAs were potential biomarkers for Cd exposure; 7 miRNAs were up-regulated, and 16 miRNAs were down-regulated. The expression levels of miR-122, novel-miR6, miR-193a-3p and miR-27a-5p in the Cd group were 0.43-fold, 0.47-fold, 0.49-fold and 2.4-fold greater than in the control group, respectively. qRT-PCR further detected that the expression levels of apoptosis-related genes, including BAX, BAD, BAK, CASPASE9 and PIDD, were differentially increased, while BCL2 was decreased. Western blot analysis showed that the protein expression levels of BAX and BAD were increased and that of BCL2 was differentially decreased during Cd exposure. Alterations in the levels of miR-122, novel-miR6, miR-193a-3p and miR-27a-5p expression may play an important role in diagnosing oxidative stress-induced apoptosis during Cd exposure in the head kidney. These markers may contribute to diagnosing the early stage of Cd exposure in common carp.

Di-(2-ethyl hexyl) phthalate induces necroptosis in chicken cardiomyocytes by triggering calcium overload

Di-(2-ethyl hexyl)phthalate (DEHP) is a kind of plasticizer that can cause cardiovascular disorders in animals, but its specific mechanism of action has not been determined. We aimed to investigate whether taxifolin (TAX) can antagonize the cytotoxicity of DEHP on cardiomyocytes. Chicken cardiomyocytes were treated with DEHP (500 μM) and/or TAX (0.5 μM) for 24 h. Ca²⁺ staining showed that the concentration of Ca²⁺ in the cytoplasm of cardiomyocytes was significantly increased under DEHP stimulation. However, in the DEHP + TAX group, the Ca²⁺ concentration was largely restored. In addition, the results of necroptosis--fluorescent and flow cytometry analysis showed that the DEHP group had severe necroptosis compared with the control group. The necrotic rate in the DEHP + TAX group was significantly lower than that in the DEHP group. At the mRNA and protein levels, the expression of the necrotic-calcium pathway genes RIPK1, RIPK3, MLKL, FAS, Caspase-8, CAMKII, and SERCA in the DEHP group increased to varying degrees relative to the control group. However, TAX improved this injury. Compared with the DEHP group, the expression of these genes was significantly decreased in the DEHP + TAX group. The present study indicate that DEHP could trigger cardiomyocyte necroptosis through Ca²⁺ overload, which could be alleviated by TAX.

Chlorpyrifos induces redox imbalance-dependent inflammation in common carp lymphocyte through dysfunction of T-cell receptor γ

Chlorpyrifos is a poisonous pesticide that is highly toxic to fish and aquatic organisms. However, there are fewer reports about how chlorpyrifos influences the redox balance of immune cells. Herein, the head kidney tissue treated with chlorpyrifos to do transcriptome analysis and TCR γ was screened out. Subsequently, we established TCR γ knockdown and overexpression carp head kidney lymphocyte models, respectively, by using RNA interference and pcDNA3.1. Real-time PCR, fluorescent staining, oxidation and antioxidant kit were used to detect the related factors. We found that TCR γ knockdown significantly increased the mRNA expression of HSP70 and HSP90 and decreased the mRNA expression of SOD and CAT. Meanwhile, TCR γ knockdown reduced the activities of GSH, GSG-PX, T-AOC, CAT and SOD and increased the content of MDA and H₂ O₂ and activities of iNOS. Adverse results were obtained in TCR γ overexpression group. Additionally, TCR γ knockdown significantly increased the mRNA expression of IFN-γ, IL-1β, IL-8, IL-10, Nrf2 and NF-κB, but relieved TCR γ overexpression, in which the process of inflammation was activated. Our results reported here indicated that chlorpyrifos induces redox imbalance-dependent inflammation in common carp lymphocyte through dysfunction of T-cell receptor γ, and HSPs play potential protective role in entire process.

Chlorpyrifos induces apoptosis and autophagy in common carp lymphocytes by influencing the TCR γ-dependent PI3K/AKT/JNK pathway

Chlorpyrifos is an insecticide that is widely used in agricultural production. However, little is known about how chlorpyrifos disrupts lymphocyte homeostasis in common carp. Herein, we identified TCRγ through the results of transcriptome analysis. Subsequently, we established TCR γ knockdown and overexpression models in carp head kidney lymphocyte respectively using RNA interference and the pcDNA3.1 plasmid, respectively. Real-time PCR, fluorescent staining, ultrastructure observation and flow cytometry were used to detect the levels of the PI3K/AKT pathway, autophagy and apoptosis. Our results demonstrated that chlorpyrifos significantly decreased the expression of TCR γ, TCR γ suppression thereby induced increased mRNA expression of TNF-α, Bax, caspase-3, caspase-8, caspase-9 and significantly inhibited the expression of Bcl-2, which indicated that apoptosis was triggered. This conclusion was supported by our flow cytometry and ultrastructure observation results. In addition, the control and TCR γ overexpression groups had normal cell morphology. Moreover, TCR γ suppression activated the expression of Becline-1, ATG5, ATG10, ATG12, ATG16 and reduced the expression of mTOR, with the opposite results observed in the TCR γ overexpression group. Together, these results suggested that TCR γ imbalance triggers apoptosis and autophagy in lymphocyte. Moreover, we found that TCR γ knockdown significantly increased the mRNA expression of JNK and decreased the expression of PI3K and AKT, which indicated that the PI3K/AKT/JNK pathway was activated. Our results reported here indicated that chlorpyrifos induces apoptosis and autophagy in head kidney lymphocyte through the inhibition of TCR γ.

Excessive Cu2+ deteriorates arsenite-induced apoptosis in chicken brain and resulting in immunosuppression, not in homeostasis

Trace elements such as copper (Cu) and arsenic (As) are two of the major contaminants and well-known inducers of cognitive deficits and neurobehavioral changes. This study evaluated the immunotoxicity of their individual or combined exposure on different brain regions in chickens. Consequently, nuclear damage and organelle lesions, especially mitochondria were observed under Cu or/and As stress, in which positive regulation of key proteins, dynamin-related protein 1 (Drp1), Cytochrome C (Cyt c), BCL2-associated X (Bax), Caspases 3 and P53 was detected by qRCR and Western blot analyses, indicating disturbed mitochondrial dynamic equilibrium and apoptosis execution. In addition, qRCR analysis confirmed the involvement of cytokines secreted by different populations of helper T cells, indicative of cellular immunity. Gene expression studies showed marked up regulation of Th1/Th17 cytokines along with heat shock protein (HSP) 70, a synergism was noted in co-administration group. Interesting, lower apoptosis index was noted in brainstem compared to cerebrum and cerebellum. An intense immunosuppression and heat shock response against Cu or/and As was also seen in cerebrum and cerebellum but not in brainstem. In conclusion, our study suggests a synergistic neurotoxicity in chickens under Cu and As exposure. These findings provide a basic understanding of mitochondrial abnormality-initiated neuropathology in response to environmental pollutant mixtures, suggesting an adaptive response to the frangibility of the central nerve system.

IGF1 Knockdown Hinders Myocardial Development through Energy Metabolism Dysfunction Caused by ROS-Dependent FOXO Activation in the Chicken Heart

Insulin-like growth factor 1 (IGF1) is a multifunctional cellular regulatory factor that can regulate cell growth and development by mediating growth hormone stimulation. However, the mechanism of IGF1 dysfunction in cardiomyocyte development is seldom reported. To study this, we employed the models of IGF1 knockdown in chicken embryo in vivo and in cardiomyocytes in vitro. We detected the antioxidant capacity, PI3K/Akt pathway, energy metabolism-related genes, and myocardial development-related genes. Our results revealed that the low expression of IGF1 can significantly suppress the antioxidant capacity and increase the ROS (P < 0.05) levels, activating the AMPK and PI3K pathway by inhibiting the expression of IRS1. We also found that myocardial energy metabolism is blocked through IGF1, GLUT, and IGFBP inhibition, further inducing myocardial developmental disorder by inhibiting Mesp1, GATA, Nkx2.5, and MyoD expression. Altogether, we conclude that low IGF1 expression can hinder myocardial development through the dysfunction of energy metabolism caused by ROS-dependent FOXO activation.

Taxifolin ameliorates DEHP-induced cardiomyocyte hypertrophy via attenuating mitochondrial dysfunction and glycometabolism disorder in chicken

Di-(2-ethylhexyl) phthalate (DEHP) is a prevalent environmental contaminant that severely impacts the health of human and animals. Taxifolin (TAX), a plant flavonoid isolated from yew, exerts protective effects on cardiac diseases. Nevertheless, whether DEHP could induce cardiomyocyte hypertrophy and its mechanism remains unclear. This study aimed to highlight the specific molecular mechanisms of DEHP-induced cardiomyocyte hypertrophy and the protective potential of TAX against it. Chicken primary cardiomyocytes were treated with DEHP (500 μM) and/or TAX (0.5 μM) for 24 h. The levels of glucose and adenosine triphosphate (ATP) were detected, and cardiac hypertrophy-related genes were validated by real-time quantitative PCR (qRT-PCR) and Western blot (WB) in vitro. The results showed that DEHP-induced cardiac hypertrophy was ameliorated by TAX, as indicated by the increased cardiomyocyte area and expression of atrial natriuretic peptide (ANP), natriuretic peptides A-like (BNP) and β-myosin heavy cardiac muscle (β-MHC). Furthermore, DEHP induced cardiac hypertrophy via the interleukin 6 (IL-6)/Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathway in vitro. In addition, DEHP disrupted mitochondrial function and glycometabolism by activating the insulin-like growth factor 1 (IGF1)/phosphatidylinositol 3-kinase (PI3K) pathway and the peroxisome proliferator activated receptors (PPARs)/PPARG coactivator 1 alpha (PGC-1α) pathway to induce cardiac hypertrophy in vitro. Intriguingly, those DEHP-induced changes were obviously alleviated by TAX treatment. Taken together, cardiac hypertrophy was induced by DEHP via activating the IL-6/JAK/STAT3 signaling pathway, triggering glycometabolism disorder and mitochondrial dysfunction in vitro, can be ameliorated by TAX. Our findings may provide a feasible molecular mechanism for the treatment of cardiomyocyte hypertrophy induced by DEHP.

Taxifolin alleviates apoptotic injury induced by DEHP exposure through cytochrome P450 homeostasis in chicken cardiomyocytes

Di-2-ethylhexyl phthalate (DEHP), widely used as a plasticizer, is a ubiquitous artificial pollutant. DEHP can induce biological toxicity in various organs, with an especially high potential for toxicity to the cardiovascular system. Taxifolin (TAX) is used in the treatment of cardiovascular diseases due to its antioxidative capacities. However, it is not clear whether TAX can alleviate apoptosis induced by DEHP exposure through the cytochrome P450 (CYP) pathway in cardiomyocytes. To understand the role of TAX in attenuating cardiomyocyte toxicity induced by DEHP, primary cardiomyocytes were divided into 4 groups (control group, DEHP group, TAX group and DEHP + TAX group). The results showed that in the cardiomyocytes, DEHP initiated apoptosis by increasing the expression of caspase-3, caspase-9, cyt c, and Bax at both the mRNA and protein levels and by decreasing the Bcl-2 levels compared with that of the control group. In addition, the activities of catalase (CAT), superoxide dismutase (SOD), and total antioxidative capacity (T-AOC) were clearly decreased (P < 0.05), while in the DEHP group, the malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) levels were observably increased (P < 0.05), compared with those in control group. Furthermore, compared with the control group, the DEHP group demonstrated a clear partial decrease in the expression of the mRNA levels of CYP1B1 and CYP2C18 (P < 0.05), and DEHP/TAX cotreatment partially prevented apoptosis and oxidative stress damage (P < 0.05). These results showed that exposure to DEHP induced apoptosis in chicken cardiomyocytes, while TAX could antagonize the toxicity of DEHP on cardiomyocytes by attenuating oxidative stress responses and modulating CYPs.

Atrazine induces necroptosis by miR-181-5p targeting inflammation and glycometabolism in carp lymphocytes

Atrazine (ATR) causes environmental problems and damages the health of fish and aquatic animals. MicroRNAs (miRNAs) play important roles in immune regulation. However, the immunotoxicity mechanism of ATR in fish lymphocytes and the role of miRNA in this process remain unclear. To further study these mechanisms, spleen lymphocytes were exposed to 20, 40 and 60 μg/ml ATR for 18 h. Fluorescence staining and flow cytometry showed that the number of necrotic lymphocytes increased after ATR exposure. Compared with the control group, the mRNA expression of miR-181-5p was inhibited and the mRNA levels of TNF-α and HK2 were increased after ATR exposure. Additionally, the NF-κB inflammatory pathway and the levels of glycometabolism-related genes were upregulated. These results suggest that ATR induces inflammation and elevates glycometabolism in lymphocytes. We further found that the mRNA levels of receptor-interacting serine-threonine kinase 1 (RIP1), receptor-interacting serine-threonine kinase 3 (RIP3), mixed lineage kinase domain-like pseudokinase (MLKL), cylindromatosis (CYLD) and Fas-Associated protein with Death Domain (FADD) and the protein levels of RIP3 and MLKL in the treatment groups were significantly increased compared to those in control group, suggesting that ATR causes lymphocyte necroptosis. We conclude that miR-181-5p plays a key role in necroptosis in carp lymphocytes exposed to ATR by downregulating the expression of HK and TNF-α, which increases the level of glycometabolism and induces the inflammatory response, respectively.

Role of miR-731 and miR-2188-3p in mediating chlorpyrifos induced head kidney injury in common carp via targeting TLR and apoptosis pathways

Chlorpyrifos (CPF) is an environmental pollutant with increasing importance due to its high toxicity to fish and aquatic animals. In the present study, we divided 120 common carp (Cyprinus carpio L.) into two groups including control group and CPF group, CPF group was exposed to 14.5 μg/L CPF for 30 d. 17 miRNAs were differentially expressed in CPF group head kidney tissues according to the results of miRNAome analysis. In addition, histopathological examination and electron microscopy proved that CPF exposure could lead to damage of head kidney and obvious apoptosis characteristics. The possible target genes of miRNA were predicted using online target gene prediction websites, miRNAome sequencing, GO and KEGG enrichment. miRNAome results showed that expression of miR-731 and miR-2188-3p in CPF group was 0.48 time and 0.45 time as control group, respectively. qRT-PCR results proved the reality of miRNAome. During CPF exposure, mRNA expression of TLR pathway genes and its downstream genes involved in autophagy and apoptosis pathway including TLR1, TLR2, TLR7, TLR9, MyD88, IRAK1, IRAK4, IRF7, PI3K, AKT, mTOR, Caspase3, Caspase8 and Bax were differentially increased under CPF exposure, along with ATG13 and Bcl2 decreased at the same time. Western blot results indicated that apoptosis related protein Caspase3 and Caspase8 were differentially up-regulated in the CPF group. In summary, CPF exposure could induce apoptosis while inhibited autophagy in head kidney of common carp via the regulation of miR-2188-3p and miR-731 by targeting TLR pathway. These results provide new insights for unveiling the biological effects of CPF and miRNAs in common carp.