Hydrogen sulfide exposure induces jejunum injury via CYP450s/ROS pathway in broilers

Lambda-cyhalothrin induces heart injury in chickens by regulating cytochrome P450 enzyme system and inhibiting Nrf2/HO-1 pathway

Lambda-cyhalothrin (LCT) is a common pyrethroid insecticide widely used for ectoparasite control and hygiene pest prevention in poultry and this study aimed to investigate the mechanisms of LCT-induced cardiac injury in chickens. Low, medium, and high-dose LCT exposure models in chickens were established and hematoxylin and eosin (H&E) staining, dihydroethidium (DHE) staining, TUNEL staining, immunofluorescence, biochemical analysis, and gene expression analysis were used to study the effects of LCT exposure on the chicken heart. The results showed that LCT exposure increased the serum levels of creatine kinase (CK) and lactate dehydrogenase (LDH), led to muscle fiber breakage and inflammatory cell infiltration and caused cardiac tissue damage. The DHE staining and biochemical analysis revealed that LCT exposure resulted in the excessive accumulation of ROS, decreased activities/levels of catalase (CAT), total superoxide dismutase (T-SOD), and glutathione (GSH), and increased levels of the oxidative damage marker malondialdehyde (MDA). The TUNEL staining indicated that LCT exposure increased apoptosis possibly through the elevated expression of pro-apoptotic genes in the mitochondrial pathway, the reduced expression of anti-apoptotic genes, the upregulation of pro-inflammatory factors and the downregulation of anti-inflammatory factors. Here, LCT exposure significantly inhibited the expression of genes in the Nrf2/HO-1 pathway and activated the expression of genes in the CYP450 enzyme system. Compared to the low-dose group, the high-dose LCT exposure group showed lower levels of apoptosis and inflammation, possibly related to the low oxidative stress levels mediated by the decreased expression of the CYP450 enzyme system. In conclusion, LCT exposure induces oxidative stress, apoptosis, and inflammation in chicken hearts, which may be associated with the inhibition of the Nrf2/HO-1 pathway and activation of the CYP450 enzyme system. This study provides a theoretical basis for the safer use of insecticides in poultry production.

Tea tree oil inhibits hydrogen sulfide-induced oxidative damage in chicken lungs through CYP450s/ROS pathway

A large amount of hydrogen sulfide (H2S) is produced in the process of chicken breeding, which can cause serious inflammation and oxidative damage to the respiratory system of chickens. Tea tree oil (TTO) has antioxidant and anti-inflammatory properties. No studies have been reported on the use of TTO in H2S-induced lung injury in chickens. Therefore, in this study, 240 one-day-old Roman pink laying hens were randomly and equally divided into 3 groups: control group (CON), H2S exposure group (AVG, containing H2S), and TTO treatment group (TTG, containing H2S and 0.02 mL/L TTO) to establish an experimental model of TTO treatment with H2S exposure for a period of 42 d. Hematoxylin and eosin (H&E) staining was used to detect lung histopathology. Gene expression profiles were analyzed using transcriptomics. The underlying mechanism of the amelioration of lung injury by TTO was further revealed by antioxidant enzyme assays and qRT-PCR. The results showed that H2S exposure induced significant gene expression of CYP450s (CYP1B1 and CYP1C1) (P < 0.05), and caused intense oxidative stress, apoptosis and inflammation compared with CON. TTO could reduce ROS production and enhance antioxidant capacity (SOD, CAT, T-AOC, and GSH-PX) by regulating the CYP450s/ROS pathway (P < 0.05). Compared with the control group, the treatment group showed significantly decreased expression of apoptotic (Caspase-8, Caspase-3, Bid and Fas) (P < 0.05) and inflammatory (IL-4, IL-16, NF-κB, TNF-α and IFN-γ) (P < 0.05) factors in the lung. This study revealed that TTO regulated CYP450s/ROS pathway to alleviate H2S-induced lung injury in chickens. These results enrich the theory of the action mechanism of TTO on H2S-exposed chicken lungs and are of great value for the treatment of H2S-exposed animals.

Chronic inhalation of H2S in low concentration induces immunotoxicity and inflammatory effects in lung tissue of rats

Hydrogen sulfide (H2S) is a typical odour compound mainly causing respiratory and central nervous system symptoms. However, the immunotoxicity of inhaled H2S and the underlying mechanisms remain largely unknown. In this study, a low-dose inhalation exposure to H2S was arranged to observe inflammatory response and immunotoxicity in lung tissue of rats. Low concentrations of H2S exposure affected the immune level of pulmonary tissue and peripheral blood. Significant pathological changes in lung tissue in the exposure group were observed. At low concentration, H2S not only induced the upregulation of AQP-4 and MMP-9 expression but also stimulated immune responses, initiating various anti-inflammatory and inflammatory factors, altering tissue homeostatic environments. The TNF and chemokine signaling pathway played an important role which can promote the deterioration of pulmonary inflammatory processes and lead to lung injury and fibrosis. Excessive immune response causes an inflammatory effect and blood-gas barrier damage. These data will be of value in evaluating future occupational health risks and providing technical support for the further development of reliable, sensitive, and easy-to-use screening indicators of exposure injury.

Long-term Cu exposure alters CYP450s activity and induces jejunum injury and apoptosis in broilers

Copper (Cu) is an essential trace element that plays a crucial role in numerous physiopathological processes related to human and animal health. In the poultry industry, Cu is used to promote growth as a feed supplement, but excessive use can lead to toxicity on animals. Cytochrome P450 enzymes (CYP450s) are a superfamily of proteins that require heme as a cofactor and are essential for the metabolism of xenobiotic compounds. The purpose of this study was to explore the influence of exposure to Cu on CYP450s activity and apoptosis in the jejunum of broilers. Hence, we first simulated the Cu exposure model by feeding chickens diets containing different amounts of Cu. In the present study, histopathological observations have revealed morphological damage to the jejunum. The expression levels of genes and proteins of intestinal barrier markers were prominently downregulated. While the mRNA expression level of the gene associated with CYP450s was significantly increased. Additionally, apoptosis-related genes and proteins (Bak1, Bax, Caspase-9, Caspase-3, and CytC) were also significantly augmented by excessive Cu, while simultaneously decreasing the expression of Bcl-2. It can be concluded that long-term Cu exposure affects CYP450s activity, disrupts intestinal barrier function, and causes apoptosis in broilers that ultimately leads to jejunum damage.

Integrated transcriptomics and metabolomics reveal the toxic mechanisms of mercury exposure to an endangered species Tachypleus tridentatus

Mercury (Hg) pollution is threatening the health of endangered Tachypleus tridentatus whereas the toxic mechanism is still unclear. This study combined transcriptomic and metabolomics technology to reveal the toxic mechanisms of mercury (Hg 2+, 0.025 mg/L) exposing to T. tridentatus larvae for 15 days. Mercury induced cellular toxicity and cardiovascular dysfunction by dysregulating the genes related to endocrine system, such as polyubiquitin-A, cathepsin B, atrial natriuretic peptide, etc. Mercury induced lipid metabolic disorder with the abnormal increase of lysoPC, leukotriene D4, and prostaglandin E2. Cytochrome P450 pathway was activated to produce anti-inflammatory substances to reconstruct the homeostasis. Mercury also inhibited arginine generation, which may affect the development of T. tridentatus by disrupting the crucial signaling pathway. The mercury methylation caused enhancement of S-adenosylmethionine to meet the need of methyl donor. The mechanisms described in present study provide new insight into the risk assessment of mercury exposure to T. tridentatus.

Metabolomics and Transcriptomics Analyses of Curcumin Alleviation of Ochratoxin A-Induced Hepatotoxicity

Ochratoxin A (OTA) is one of the mycotoxins that poses a serious threat to human and animal health. Curcumin (CUR) is a major bioactive component of turmeric that provides multiple health benefits. CUR can reduce the toxicities induced by mycotoxins, but the underlying molecular mechanisms remain largely unknown. To explore the effects of CUR on OTA toxicity and identify the key regulators and metabolites involved in the biological processes, we performed metabolomic and transcriptomic analyses of livers from OTA-exposed mice. We found that CUR can alleviate the toxic effects of OTA on body growth and liver functions. In addition, CUR supplementation significantly affects the expressions of 1584 genes and 97 metabolites. Integrated analyses of transcriptomic and metabolomic data showed that the pathways including Arachidonic acid metabolism, Purine metabolism, and Cholesterol metabolism were significantly enriched. Pantothenic acid (PA) was identified as a key metabolite, the exogenous supplementation of which was observed to significantly alleviate the OTA-induced accumulation of reactive oxygen species and cell apoptosis. Further mechanistical analyses revealed that PA can downregulate the expression level of proapoptotic protein BAX, enhance the expression level of apoptosis inhibitory protein BCL2, and decrease the level of phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2). This study demonstrated that CUR can alleviate the adverse effects of OTA by influencing the transcriptomic and metabolomic profiles of livers, which may contribute to the application of CUR in food and feed products for the prevention of OTA toxicity.

The mechanism of cadmium exposure-induced lymph node necroptosis and inflammation in piglets: Activation of CYP450 through VDR / CREB1 pathway

Cadmium (Cd) is toxic non-essential heavy metal that precipitates adverse health effects in humans and animals, but the effect of Cd on lymph node toxicity of piglets is still unclear. In order to explore the possible molecular mechanism of Cd toxicity to lymph nodes of piglets, ten 6-week-old male weaned piglets were randomly divided into two groups, C group and Cd group. Group C was fed with basal diet, while group Cd was fed with basal diet supplemented with CdCl2 (20 mg/kg) for 40 days, the pigs were euthanized and the mesenteric, inguinal and submandibular lymph nodes (MLN, ILN, SLN) were collected. The results indicated that Cd could induce the inflammatory cell infiltration, microvascular hemorrhage, microthrombosis and cell necrosis in MLN, ILN and SLN of piglets, induced Cytochrome P450 proteins (CYP1A1、CYP2E1、CYP2A1 and CYP3A2) mRNA levels and the protein levels of Vitamin D receptor (VDR) and cAMP response element binding protein 1 (CREB1). In addition, Cd exposure upregulated the mRNA and protein levels of dynamin-related protein 1 (DRP1), receptor-interacting protein kinase 3 (RIP3), mixed lineage kinase domain-like protein (MLKL), and increased tumor necrosis factor-α (TNFα), interferon-γ (IFNγ), interleukin-2 (IL-2), interleukin-4 (IL-4), cyclooxygenase 2 (COX-2) protein levels, and the damage degree of three kinds of lymph nodes was similar after Cd exposure. In general, these results manifest that Cd exposure regulates VDR/CREB1 pathway, activates CYP450s, induces necroptosis of lymph nodes, and leads to inflammation.

Butyric acid inhibits oxidative stress and inflammation injury in calcium oxalate nephrolithiasis by targeting CYP2C9

This study investigates the mechanism by which butyric acid can protect against calcium oxalate (CaOx) nephrolithiasis. To do so, a rat model was used with 0.75% ethylene glycol administration to induce CaOx crystal formation. Histological and von Kossa staining revealed calcium deposits and renal injury, while dihydroethidium fluorescence staining was used to detect reactive oxygen species (ROS) levels. Flow cytometry and TUNEL assays were used to assess apoptosis, respectively. Treatment with sodium butyrate (NaB) was found to partially reverse the oxidative stress, inflammation, and apoptosis associated with CaOx crystallization in the kidney. In addition, in HK-2 cells, NaB reversed the decreased cell viability, increased ROS levels and apoptosis damage caused by oxalate exposure. Network pharmacology was employed to predict the target genes of butyric acid, CYP2C9. Subsequently, NaB was found to significantly reduce CYP2C9 levels in vivo and in vitro, and inhibition of CYP2C9 by Sulfaphenazole (a specific CYP2C9 inhibitor), was able to reduce ROS levels, inflammation injury, and apoptosis in oxalate-induced HK-2 cells. Collectively, these findings suggest that butyric acid may inhibit oxidative stress and reduce inflammation injury in CaOx nephrolithiasis by suppressing CYP2C9.

Modulation of the immune system of chickens a key factor in maintaining poultry production-a review

The awareness of poultry production safety is constantly increasing. The safety of poultry production is defined as biosecurity and the health status of birds. Hence the constant pursuit of developing new strategies in this area is necessary. Biosecurity is an element of good production practices that ensures adequate hygiene and maintaining the health status of poultry production. Poultry production is the world leader among all livestock species. Producers face many challenges during rearing, which depend on the utility type, the direction of use, and consumer requirements. For many years, the aim was to increase production results. Increasing attention is paid to the quality of the raw material and its safety. Therefore, it is crucial to ensure hygiene status during production. It can affect the immune system's functioning and birds' health status. Feed, water, and environmental conditions, including light, gases, dust, and temperature, play an essential role in poultry production. This review aims to look for stimulators and modulators of the poultry immune system while affecting the biosecurity of poultry production. Such challenges in current research by scientists aim to respond to the challenges posed as part of the One Health concept. The reviewed issues are a massive potential for an innovative approach to poultry production and related risks as part of the interaction of the animal-human ecosystem.

Correlation analysis between jejunum metabolites and immune function in Saba and Landrace piglets

The immune function of the intestinal mucosa plays a crucial role in the intestinal health of hosts. As signaling molecules and precursors of metabolic reactions, intestinal chyme metabolites are instrumental in maintaining host immune homeostasis. Saba (SB) pigs, a unique local pig species in central Yunnan Province, China. However, research on jejunal metabolites in this species is limited. Here, we used immunohistochemistry and untargeted metabolomics by liquid chromatography mass spectrometry (LC-MS/MS) to study differences in jejunal immunophenotypes and metabolites between six Landrace (LA) and six SB piglets (35 days old). The results showed that the levels of the anti-inflammatory factor interleukin 10 (IL-10) were markedly higher in SB piglets than in LA piglets (P &lt; 0.01), while the levels of the proinflammatory factors IL-6, IL-1β, and Toll-like receptor 2 (TLR-2) were markedly lower (P &lt; 0.01). Furthermore, the levels of mucin 2 (MUC2) and zona occludens (ZO-1), which are related to mucosal barrier function, were significantly higher in SB piglets than in LA piglets (P &lt; 0.01), as were villus height, villus height/crypt depth ratio, and goblet cell number (P &lt; 0.05). Differences in jejunal chyme metabolic patterns were observed between the two piglets. In the negative ion mode, cholic acid metabolites ranked in the top 20 and represented 25% of the total. Taurodeoxycholic acid (TDCA) content was significantly higher in SB piglets than in LA piglets (P &lt; 0.01). TDCA positively correlated with ZO-1, villus height, villus height/crypt depth ratio, and goblet cell number. These results suggest that SB pigs have a strong jejunal immune function and that TDCA was positively regulates jejunal immunity and mucosal barrier function. Our findings provide a reference for understanding intestinal immune function in different pig breeds and for the discovery of potential biomarkers to help solve health issues related to pig production.

Tannic acid through ROS/TNF-α/TNFR 1 antagonizes atrazine induced apoptosis, programmed necrosis and immune dysfunction of grass carp hepatocytes

Atrazine (ATR) is a commonly used triazine herbicide, which will remain in the water source, soil and biological muscle tissue for a long time, threatening the survival of related organisms and future generations. Tannic acid (TAN), a glucosyl compound found in gallnuts, has previously been shown to antagonize heavy metal toxicity, antioxidant activity, and inflammation. However, it is unclear whether TAN can antagonize ATR-induced Grass carp hepatocytes (L8824 cells) cytotoxicity. Therefore, we treated L8824 cells with 3 μg mL^-1 ATR for 24 h to establish a toxic group model. The experimental data of flow cytometry and AO/EB staining together showed that the ratio of apoptosis and necrosis in L8824 cells after ATR exposure was significantly higher than that in the control group. Furthermore, RT-qPCR showed that inflammatory factors (TNF-α, IL-1β, IL-6, INF-γ) were up-regulated and antimicrobial peptides (hepcidin, β-defensin and LEAP2) were induced down-regulated in L8824 cells, leading to immune dysfunction. The measurement results of oxidative stress-related indicators showed that the levels of ROS and MDA increased after ATR exposure, the overall anti-oxidative system was down-regulated. Western blotting confirmed that TNF-α/TNFR 1-related genes were also up-regulated. This indicates that ATR stimulates oxidative stress in L8824 cells, which in turn promotes the binding of TNF-α to TNFR 1. In addition, TRADD, FADD, Caspase-3, P53, RIP1, RIP3 and MLKL were found to be significantly up-regulated by Western blotting and RT-qPCR. Conditioned after ATR exposure compared to controls. It indicates that ATR activates apoptosis and necrosis of TNF-α/TNFR 1 pathway by inducing oxidative stress in L8824 cells. Furthermore, the use of TAN (5 μM) significantly alleviated the toxic effects of ATR on L8824 cells mentioned above. In conclusion, TAN restrains ATR-induced apoptosis, programmed necrosis and immune dysfunction through the ROS/TNF-α/TNFR 1 pathway.

Dietary rosemary extract modulated gut microbiota and influenced the growth, meat quality, serum biochemistry, antioxidant, and immune capacities of broilers

After the legislative ban on the utilization of antibiotics in animal feed, phytochemical substances gained increasing attention as alternatives to antibiotics because of their bioactivities and safety for animals. The present study aimed to investigate the influence of dietary rosemary extract (RE) on growth performance, meat quality, serum biochemistry, antioxidant and immune capacities, and gut microbiota composition of broilers. By exploring connections among RE, physiological characteristics of broilers, and key microbiota, we sought to provide evidence for the utilization of RE in poultry feed. A total of 280 1-d-old female AA broilers were randomly separated into five groups, and were fed a basal diet supplemented with 0, 250, 500, 750, and 1,000 mg/kg of RE, respectively. Results showed that with regard to growth performance, both 500 and 750 mg/kg RE reduced the broiler feed-to-gain ratio from 1 to 21 d (P = 0.018). Regarding meat quality, all compositions of dietary RE reduced cooking loss of breast muscle (P < 0.01), and 500 and 1,000 mg/kg RE reduced the cooking loss of thigh muscle (P = 0.045). Regarding serum biochemical indexes, 500 mg/kg RE reduced ALB, TCHO, HDL-C, and LDL-C, and 750 mg/kg RE reduced GLU, TP, ALB, UA, TG, TCHO, HDL-C, and LDL-C (P < 0.01). Regarding antioxidant and immune capacities, 250, 500, 750, and 1,000 mg/kg RE increased T-AOC, GSH-Px, SOD, CAT, IL-2, IgA, IgG, and IgM levels (P < 0.01), and decreased serum MDA level (P < 0.01). RE at 750 mg/kg showed similar effects on growth performance, meat quality, and antioxidative and immune capacities, but a better influence on serum biochemical indexes of broilers compared with 500 mg/kg. Further analysis was conducted to investigate the effect of 750 mg/kg dietary RE on the gut microbial composition of broilers, and the results showed that 750 mg/kg RE reduced the relative abundance of g_Lachnoclostridium, g_Escherichia_Shigella, and g_Marvinbryantia (P <0.05, LDA score >2), which were negatively correlated to antioxidative and immune-associated parameters (P < 0.05). In conclusion, 750 mg/kg dietary RE was shown to have certain beneficial effects on growth performance and meat quality, and hypolipidemic and hypoglycemic effects on broilers. Furthermore, dietary RE improved antioxidant and immune capacities, which was partially attributed to the reduced abundance of certain pathogenic bacteria in broilers.

Antrodia cinnamomea polysaccharide improves liver antioxidant, anti-inflammatory capacity, and cecal flora structure of slow-growing broiler breeds challenged with lipopolysaccharide

Lipopolysaccharides (LPS) induces liver inflammatory response by activating the TLR4/NF-κB signaling pathway. Antrodia cinnamomea polysaccharide (ACP) is a medicinal mushroom that can protect from intoxication, liver injury, and inflammation. Nevertheless, the effect of ACP on the liver antioxidant, anti-inflammatory capacity and cecal flora structure of LPS-challenged broilers remains unclear. The aim of this experiment was to investigate the effects of ACP on the anti-oxidative and anti-inflammatory capacities of the liver, and cecal microbiota in slow-growing broilers stimulated by LPS. A total of 750 slow-growing broilers (9-day-old) were assigned to five treatments with 6 replicates of 25 chicks per replicate: a control diet, the chicks were fed a control diet and challenged with LPS. Dietary treatments 3 to 5 were the control diet supplemented with 100, 200, 400 mg/kg ACP challenged with LPS, respectively. The groups of 100 mg/kg ACP supplementation significantly increased liver index, pancreas index, and bursa of Fabricius index (P < 0.05). The GSH-Px content of LPS-challenged broilers was lower than that of the control group (P < 0.001), but the content of MDA increased (P < 0.001). Feeding with 100 mg/kg ACP resulted in increased the activity of T-AOC, GSH-Px, and T-SOD, and decreased MDA content (P < 0.05). The activity of TNF-α, IL-1β, and IL-6 of the LPS group increased, but these indicators were decreased with supplemental 100 mg/kg ACP (P < 0.05). Dietary application of ACP up to 100 mg/kg down-regulated (P < 0.05) the expression of TLR4/NF-κB pathway in the liver induced by LPS. The results of 16S rRNA demonstrated that feeding with 100 mg/kg ACP can change the diversity and composition of the gut microbiota, and restrained the decline of beneficial cecal microbiota (typically Lactobacillus, Faecalibacterium, and Christensenellaceae R-7 group) in the challenged LPS group (P < 0.05). Conclusively, feeding a diet with 100 mg/kg ACP may have beneficial effects on liver damage and the bacterial microbiota diversity and composition in the ceca of LPS-stressed slow-growing broiler breeds, probably because of its combined favorable effects on antioxidants and cytokines contents, and restoration the decline of beneficial cecal microbiota.

Ammonia-induced excess ROS causes impairment and apoptosis in porcine IPEC-J2 intestinal epithelial cells

Ammonia is one of the most important toxic metabolites in the intestine of animals. It can cause intestinal damage and associated intestinal diseases through different endogenous or exogenous stimuli. However, the definition of harmful ammonia concentration and the molecular mechanism of ammonia - induced intestinal epithelial injury remain unclear. In this study, we found that the viability of porcine IPEC-J2 intestinal epithelial cells significantly decreased with the increase of NH₄Cl dose (20-80 mM). Ammonia (40 mM NH₄Cl) increased the expression level of ammonia transporter RHCG and disrupted the intestinal barrier function of IPEC-J2 cells by reducing the expression levels of the tight junction molecules ZO-1 and Claudin-1. Ammonia caused elevated levels of ROS and apoptosis in IPEC-J2 cells. This was manifested by decreased activity of antioxidant enzymes SOD and GPx, decreased mitochondrial membrane potential, and increased cytoplasmic Ca²⁺ concentration. In addition, the expression levels of apoptosis-related molecules Caspase-9, Caspase-3, Fas, Caspase-8, p53 and Bax were increased, the expression level of anti-apoptotic molecule Bcl-2 was decreased. Moreover, the antioxidant NAC (N-acetyl-L-cysteamine) effectively alleviated ammonia-induced cytotoxicity, reduced ROS level, Ca²⁺ concentration, and the apoptosis of IPEC-J2 cells. The results suggest that ammonia-induced excess ROS triggered apoptosis through mitochondrial pathway, death receptor pathway and DNA damage. This study can provide reference and theoretical basis for the definition of harmful ammonia concentration in pig intestine and the effect and mechanism of ammonia on pig intestinal health.

Recent evidence for toxic effects of NH3 exposure on lung injury: Protective effects of L-selenomethionine

Ammonia (NH₃) is a common air pollutant, which poses a serious threat to farm animals. L-selenomethionine is organic selenium (Se), which can inhibit intracellular ROS generation, block ROS-dependent autophagy, promote mitochondrial energy metabolism, and enhance the body's immunity. Lung, as an important organ of the respiratory system, is highly susceptible to the toxic effects of NH₃. However, there were few studies on the mechanism of toxic effects of NH₃ on lung tissues. The aim of this study was to investigate the effect of NH₃ on the lungs in pigs and the alleviating effect of L-selenomethionine. Twenty-four Large White*Duroc*Min pigs were randomly assigned to 4 groups: control group, NH₃ group, Se group, and NH₃ +Se group. The results showed that exposure to NH₃ caused damage and inflammation in lung tissues and significantly increased blood NH₃ concentration. NH₃ induced changes of oxidative stress indexes (GSH, GSH-Px, SOD, MDA, Keap1, Nrf2, and HO-1) and expressions of energy metabolism related genes (HK1, HK2, PFK, PK, LDHA, and HIF-1α). Ultrastructure showed that mitochondrial damage and autophagosome increased significantly, and the expression levels of autophagy related genes (Beclin1, ATG5, ATG7, ATG10, and p62) changed. However, the addition of L-selenomethionine alleviated the above changes, but there was still a significant difference compared with the control group (P < 0.05). This finding can provide a new evidence for mitigation of NH₃ toxicity.

Atmospheric Ammonia Causes Histopathological Lesions, Cell Cycle Blockage and Apoptosis of Spleen in Chickens

The experiment was conducted to investigate the effect of atmospheric ammonia (NH3) on histological changes, cell cycle distribution, and apoptosis of spleen in chickens. 240 chickens were randomly allocated to control group (without NH3 challenge) and NH3 group (70±5 ppm NH3). The experiment lasted for eight days. The results showed that NH3 exposure caused the decreased relative weight (P<0.05), dysplasia of lymphatic follicle, up-regulation of G0G1 phase cells, excessive apoptosis, and increase of reactive oxygen spcecies (ROS) activated cells (P<0.05) in the spleen. The mechanisms of cell cycle blockage were closely related to the upregulation of p53, p21 gene (P<0.05), the downregulation of cyclinD1, cdk6 gene (P<0.05), and the decrease of Proliferating Cell Nuclear Antigen (PCNA) protein (P<0.05). The activated apoptosis could resulted from the increased gene and protein expressions of bax and caspase-3 (P<0.05), and the decreased gene and protein expressions of bcl-2 (P<0.05). The results suggested that 70±5 ppm NH3 caused the spleen dysplasia, which were closely related to the cell cycle arrest and mitochondria apoptotic pathway activation.

Albicanol modulates oxidative stress and the p53 axis to suppress profenofos induced genotoxicity in grass carp hepatocytes

The organophosphorus pesticide profenofos (PFF) is widely used as an environmental contaminant, and it can remain in water bodies causing serious harm to aquatic organisms. Albicanol is a sesquiterpenoid with potent antioxidant and antagonistic activities against heavy metal toxicity. However, the mechanism of PFF induced genotoxicity in fish hepatocytes and the role Albicanol can play in this process are unknown. In this study, the model was established by treating grass carp hepatocytes with PFF (150 μM) and/or Albicanol (5 × 10^-5 μg mL^-1) for 24 h. The results showed that PFF exposure arrested L8824 cells in the G1-S phase. PFF caused the increase of MDA level in L8824 cells, while the decrease of SOD, CAT and T-AOC levels caused oxidative stress. Elevated levels of γH2AX, tail moment, tail length, % DNA and 8-OHdG indicated that PFF caused DNA damage in L8824 cells. PFF inhibited the expression levels of cell cycle related regulatory genes (cyclin A, cyclin D, cyclin E, CDK2 and CDK4) by upregulating p53/p21 genes and activating the p53 signaling pathway. Albicanol was used to significantly reduce the above effects caused by PFF exposure on hepatocytes in grass carp. Albicanol could reduce the increase in the proportion of cells in the G1-S phase caused by PFF. In summary, Albicanol could inhibit the genotoxicity of L8824 cells resulted from PFF exposure by decreasing oxidative stress and the p53 pathway.

CircRNA-IGLL1/miR-15a/RNF43 axis mediates ammonia-induced autophagy in broilers jejunum via Wnt/β-catenin pathway

With the continued increase of global ammonia emission, the damage to human or animal caused by ammonia pollution has attracted wide attention. The noncoding RNAs have been reported to regulate a variety of biological processes under different environmental stimulation via ceRNA (competing endogenous RNA) networks. Autophagy is a hallmark of tissue damage from air pollution. However, the specific role of circular RNAs (circRNAs) in the injury of intestinal tissue caused by autophagy remains unclear. Here, we established 42-days old ammonia-exposed broiler models and observed that autophagy flux in broiler jejunum was activated under ammonia exposure. Meanwhile, a total of eight significantly dysregulated expressed circRNAs were obtained and a circRNAs-miRNAs-genes interaction networks were constructed by bioinformatics analysis. Furthermore, an axis named circRNA-IGLL1/miR-15a/RNF43 was predicted to participate in the excessive autophagy by targeting RNF43. The target relationship was proved by dual-luciferase reporter assay in vitro. Mechanistically, downregulated circRNA-IGLL1 could suppress the expression of RNF43 in ammonia-exposed jejunum and the Wnt/β-catenin pathway was activated. Inhibition of miR-15a reversed autophagy caused by downregulated circRNA-IGLL1. CircRNA-IGLL1 could competitively bind miR-15a to regulate RNF43 expression, thus modulating the occurrence of autophagy. Taken together, our results showed that circRNA-IGLL1/miR-15a/RNF43 axis is involved in ammonia-induced intestinal autophagy in broilers.

Regulating of LncRNA2264/miR-20b-5p/IL17RD axis on hydrogen sulfide exposure-induced inflammation in broiler thymus by activating MYD88/NF-κB pathway

Hydrogen sulfide (H₂S) is an environmental pollutant. Chronic exposure to H₂S can damage the immune system of birds, but the detailed mechanisms of H₂S-induced thymus toxicity have not been determined. Competitive endogenous RNA (ceRNA) mechanism participates in many pathophysiological processes by regulating gene expression, including environmental pollutant-induced injury. Therefore, we investigate the specific mechanisms of ceRNA in the process of H₂S-induced thymic immune damage in broiler chickens. In the current study, 120 one-day-old male Ross 308 broilers were randomly divided into two groups (n = 60 chickens/group), raising in the control chamber (0.5 ± 0.5 ppm) or H₂S-exposed chamber (4.0 ± 0.5 ppm at 0-3 weeks of age and 20.0 ± 0.5 ppm at 4-6 weeks of age groups) to replicate the H₂S-exposed broilers. NaHS (3 mM or 6 mM) was used to treat chicken macrophages (HD11) to establish an in vitro. Histopathology and ultrastructural changes of thymus were assessed by hematoxylin and eosin (H&E) staining and transmission electron microscopy (TEM). Gene expression profiles were analyzed by using transcriptomics. The underlying mechanisms of thymic injury were further revealed by dual luciferase reporter gene assay, qRT-PCR and Western blotting. Research results showed that H₂S exposure induced an inflammatory response in thymus, with the expression of LncRNA2264 was significantly down-regulated. LncRNA2264 could competitively bind to miR-20b-5p and caused downregulation of the IL17RD. H₂S could activate inflammatory factors through the LncRNA2264/miR-20b-5p/IL17RD axis. In summary, this study suggested that LncRNA2264 acted as a miR-20b-5p molecular sponge to regulate the expression of IL17RD involved in H₂S exposure-induced thymic inflammation, which has positive implications for guiding the prevention and control of H₂S gas poisoning in livestock housing and ensuring animal welfare.

Ammonia exposure induced intestinal inflammation injury mediated by intestinal microbiota in broiler chickens via TLR4/TNF-α signaling pathway

Ammonia is a known environmental pollutant that causes injury to the intestine. Growing evidence suggests that intestinal microbiota dysbiosis involves in the development of intestinal injury under environmental pollution. However, the specific mechanism remains unexplored. To do this, broiler chicken ileal exposed to ammonia was selected as the research object. Further, antibiotic depletion of intestinal microbiota and flora transplantation were used to clarify the role of intestinal microbiota in the intestinal injury. Histopathological examination indicated inhaled ammonia caused intestinal injury. Then we observed a decrease in intestinal muc-2, claudin-1, IL-6, IL-10 in ammonia inhalation, as opposed to the control group, associated with a significant increase in TLR4, MyD88, NF-κB, TNF-α, IL-1β, caspase3. Moreover, there was a significant increase of Streptococcus, Escherichia-Shigella, Faecalibacterium, [Ruminococcus]_torques_group, Ruminococcaceae_UCG-014, unclassified_f_Lachnospiraceae, Rothia, unclassified_f_Ruminococcaceae in the inhaled ammonia exposure. Correlation analysis suggested that the altered genera were positively correlated with the expression of TLR4 and TNF-α. Moreover, transferring intestinal microbiota from ammonia exposure broiler into healthy broiler caused intestinal injury and increased TLR4 and TNF-α concentrations in recipient broiler. Furthermore, antibiotic depletion of intestinal microbiota attenuated ammonia-caused intestinal injury and reduced TLR4 and TNF-α productions. In summary, TLR4/TNF-α signaling pathway was an important regulated mechanism involved in the intestinal injury mediated by intestinal microbiota dysbiosis under inhaled ammonia.

Transcriptome Analysis Reveals the Gene Expression Changes in the Silkworm (Bombyx mori) in Response to Hydrogen Sulfide Exposure

Simple Summary

The fat body is one of the most important tissues in the body of insects due to its number of functions. Nowadays the new physiological function of H₂S has gained attention as a novel signaling molecule. H₂S performs crucial regulatory functions involving growth, the cardiovascular system, oxidative stress, and inflammation in many organisms. In this study, RNA-seq technology was used to investigate the fat body of the silkworm at the transcriptional level after H₂S exposure during the 5th larvae stage. A total of 1200 (DEGs) was identified after 7.5 µM H₂S treatment, of which 977 DEGs were up-regulated and 223 DEGs were down-regulated. DEGs were mainly involved in the transport pathway, cellular community, carbohydrate metabolism, and immune-associated signal transduction. Present research provides new insights on the gene expression changes in the fat body of silkworms after H₂S exposure.

Abstract

Hydrogen sulfide (H₂S) has been recognized for its beneficial influence on physiological alterations. The development (body weight) and economic characteristics (cocoon weight, cocoon shell ratio, and cocoon shell weight) of silkworms were increased after continuous 7.5 µM H₂S treatment. In the present study, gene expression changes in the fat body of silkworms at the 5th instar larvae in response to the H₂S were investigated through comparative transcriptome analysis. Moreover, the expression pattern of significant differentially expressed genes (DEGs) at the 5th instar larvae was confirmed by quantitative real-time PCR (qRT-PCR) after H₂S exposure. A total of 1200 (DEGs) was identified, of which 977 DEGs were up-regulated and 223 DEGs were down-regulated. Most of the DEGs were involved in the transport pathway, cellular community, carbohydrate metabolism, and immune-associated signal transduction. The up regulated genes under H₂S exposure were involved in endocytosis, glycolysis/gluconeogenesis, the citrate cycle (TCA cycle), and the synthesis of fibroin, while genes related to inflammation were down-regulated, indicating that H₂S could promote energy metabolism, the transport pathway, silk synthesis, and inhibit inflammation in the silkworm. In addition, the expression levels of these genes were increased or decreased in a time-dependent manner during the 5th instar larvae. These results provided insight into the effects of H₂S on silkworms at the transcriptional level and a substantial foundation for understanding H₂S function.

Hydrogen sulfide exposure induces pyroptosis in the trachea of broilers via the regulatory effect of circRNA-17828/miR-6631-5p/DUSP6 crosstalk on ROS production

Hydrogen sulfide (H₂S) is an air pollutant to cause tracheal injury. Pyroptosis is responsible for tissue injury through reactive oxygen species (ROS) production. Competitive endogenous RNAs (ceRNAs) chelate microRNAs and reduce their inhibitory effect on other transcripts, thus affecting ROS levels and pyroptosis. However, it is not clear how H₂S regulates pyroptosis via the ceRNA axis. Therefore, we established a broilers model of H₂S exposure for 42 days to assess pyroptosis and obtain a ceRNA network by immunohistochemistry and RNA sequencing. We detected pyroptosis induced by H₂S and verified circRNA-IGLL1-17828/miR-6631-5p/DUSP6 axis by a double luciferase reporter assay. We also measured ROS levels and the expression of pyroptotic indicators such as (Caspase1) Casp-1, Interleukin 1β (IL-1β) and Interleukin 1β (IL-18). miR-6631-5p knockdown decreased pyroptotic indicators induced by H₂S. Overexpression of miR-6631-5p or DUSP6 knockdown stimulated ROS generation and upregulated pyroptotic indicators. N-acetyl-_L-cysteine (NAC) decreased pyroptotic indicators and ROS levels both induced by miR-6631-5p. Moreover, circRNA-IGLL1-17828, participated in intermolecular competition as a ceRNA of DUSP6. In conclusion, circRNA-IGLL1-17828/miR-6631-5p/DUSP6 crosstalk regulated H₂S-induced pyroptosis in broilers trachea via ROS generation. This is the first study to reveal regulation mechanism of circRNA-related CeRNAs on pyroptosis induced by H₂S, providing important reference for environmental toxicology.

DMEP induces mitochondrial damage regulated by inhibiting Nrf2 and SIRT1/PGC-1α signaling pathways in HepG2 cells

Dimethoxyethyl phthalate (DMEP) is an environmental endocrine disruptor. However, research into the underlying mechanisms of DMEP mitochondrial toxicity is still in its infancy. We therefore expect to understand whether DMEP induced mitochondrial damage in HepG2 cells and the associated signaling pathways. DMEP (0.125, 0.25, 0.5, 1 and 2 mM) exposure for 48 h induced a notable increment in reactive oxygen species (ROS), malondialdehyde (MDA), alanine aminotransferase (ALT), aspartate transaminase (AST) and 8-hydroxydeoxyguanosine (8-OHdG) in hepG2 cells, resulting in cellular oxidative stress. Low doses of DMEP upregulated nuclear factor E2-related factor 2 (Nrf2) and downstream protein haeme oxygenase-1 (HO-1) levels and high doses down-regulated their levels. Nrf2 levels increased after ROS scavenging by N-acetyl-L-cysteine (NAC), which indicated that the Nrf2 pathway may be affected by oxidative stress. We also found that DMEP decreased ATP content, mitochondrial copy number (mtDNA), translocase of the outer membrane subunit 20 (TOM20) expression, mitochondria-encoded genes CO1, CO2, CO3, ATP6, ATP8 expression, inhibited mitochondrial biogenesis pathway, down-regulated sirtuin 1(SIRT1), PPAR gamma co-activator 1 alpha (PGC-1α), Nuclear respiratory factor 1(Nrf1), Mitochondrial transcription factor A (TFAM) content and activated PINK1/Parkin autophagy pathway. DMEP also activated the mitochondrial apoptotic pathway, causing cytochrome c cytoplasmic translocation and caspase 3 cleavage. What's more, DMEP activated the Nuclear factor-κB (NF-κB) pathway and levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) were significantly upregulated, causing an inflammatory response. In summary, DMEP can cause inflammatory response and oxidative stress in HepG2 cells, inhibited the Nrf2 pathway and mitochondrial biogenesis, and induced autophagy and apoptosis. And oxidative stress at least partially affected the Nrf2 pathway and mitochondrial biogenesis SIRT1/PGC-1α pathway.

Transcriptome analysis reveals that hydrogen sulfide exposure suppresses cell proliferation and induces apoptosis through ciR-PTPN23/miR-15a/E2F3 signaling in broiler thymus

The immune organs, like thymus, are one of the targets of hydrogen sulfide (H₂S). Previously we reported that H₂S induced the differential expression of mRNAs that implicating apoptosis in thymus, however, the roles of noncoding RNAs (ncRNAs) in H₂S-induced thymus injury are still unknown. Pollution gases could alter the expression of ncRNAs, which have been shown to play important roles in many physiological and pathophysiological processes, including immune activity. This study revealed that H₂S exposure induced 9 differentially expressed circRNAs and 15 differentially expressed miRNAs in chicken thymus. Furthermore, the circRNA - miRNA - mRNA network was constructed. We discovered that circR-PTPN23 - miR-15a - E2F3 was involved in the cell cycle and apoptosis. Further, an in vitro H₂S exposure model was established using HD11 cell line and demonstrated that H₂S suppressed cell proliferation and induced apoptosis. Moreover, ciR-PTPN23 and E2F3 were downregulated, but miR-15a was upregulated in both the thymus and HD11 cell line after H₂S exposure. Bioinformatics analysis revealed that ciR-PTPN23 directly bound to miR-15a and that E2F3 was the target gene of miR-15a. Knocking down ciR-PTPN23 suppressed HD11 proliferation and caused G1 arrest and apoptosis, however, this phenomenon could be partially reversed by ciR-PTPN23 overexpression or miR-15a silencing. In summary, the ciR-PTPN23 - miR-15a - E2F3 axis was involved in H₂S-induced cell proliferation suppression and apoptosis.

Ammonia exposure causes the imbalance of the gut-brain axis by altering gene networks associated with oxidative metabolism, inflammation and apoptosis

Ammonia is an acknowledged environment pollutant in atmosphere with irritating smell. Previous studies have shown that excessive ammonia has toxic effects on farm animals and humans. However, the detail toxicity mechanism of ammonia to pigs is still unknown so far. In order to clarify the mechanism of ammonia toxicity, we established a porcine exogenous ammonia poisoning model and assessed the effects of ammonia on the gut-brain axis by transcriptome sequencing, histological observation and chemical analysis. Our results showed that after 30 d of ammonia exposure, 578 differentially expressed genes (DEGs) and 407 DEGs were obtained in the hypothalamus and jejunum, respectively. These DEGs were enriched into Gene Ontology terms associated with inflammation, oxidative metabolism, apoptosis, and the highly expressed genes among these DEGs were verified by real-time quantitative PCR. The content of glutathione and the activities of glutathione peroxidase and superoxide dismutase were significantly decreased, while malondialdehyde content was increased after ammonia exposure. Corticotropin releasing factor, substance P, 5-hydroxytryptamine and ghrelin contents in serum elevated significantly. Furthermore, pathologic observation in the ammonia group revealed infiltration of lymphocytes in the hypothalamus and significant decrease of jejunal epithelial cells. Our results indicated that ammonia exposure mediated changes in transcriptional profiles, pathological damage, oxidative stress and brain-gut peptide of the pig jejunum and hypothalamus, and induced the imbalance of the brain-gut axis through the "oxidative stress-inflammation-apoptosis" interaction network. Our study not only provides a new perspective for the toxicity assessment of ammonia, but also enriches the toxicology mechanism of ammonia.

New insights into crosstalk between apoptosis and necroptosis co-induced by chlorothalonil and imidacloprid in Ctenopharyngodon idellus kidney cells

Overuse and co-exposure of pesticides have become a public health problem and threat seriously water health and environmental organisms and even humans. Chlorothalonil (CT) and imidacloprid (IMI) are high-selling pesticides worldwide, which can persist in the environment, and present a series of severely toxic effects on non-target animals. However, the effect of co-application on aquatic organisms is unknown. Based on the concept of the toxic unit (TU), toxic interaction of CT and IMI was evaluated and showed the additive and synergistic toxicity on Ctenopharyngodon idellus (grass carp) kidney cell line (CIK cells). Cell death analysis found an obvious increase of the apoptosis and necrosis rates exposed to CT and IMI, and aggravation when applied together. Moreover, CT and IMI co-exposure accelerated the inhibition of CYP450s/ROS/HIF-1α signal, the decline of energy metabolism, mitochondrial dynamics disorder, activation of Bcl2/Bax/Cyt C/Casp3/Casp9 pathway and RIP1/RIP3/MLKL pathway. Bioinformatics analysis showed autophagy, cell response, NOD-like receptor signaling pathway might be affected by co-exposure. In summary, the above results indicate that co-exposure to CT and IMI has synergistic toxicity and aggravates cell death via inhibition of the CYP450s/ROS/HIF-1α signal. These data provide new insights for evaluating the stacking interaction and revealing the toxicological effects of pesticide mixture.

Comparison of Chemical Constituents and Pharmacological Effects of Different Varieties of Chrysanthemum Flos in China

Chrysanthemum Flos is the prestigious traditional Chinese medicinal material and the popular health drink. This article comprehensively evaluated the chemical constituents, antioxidant activity, and hepatoprotective effects of 25 common chrysanthemum varieties in China. Firstly, we analyzed the chemical compositions of water extracts of chrysanthemum using UPLC/Q-TOF-MS, and identified 29 chemical components. The results displayed that chrysanthemum was rich in chemical constituents, but there were significant differences in the contents of four phenolic acids and five flavonoids among different varieties, and the coefficient of variation (CVs) ranged from 35.96 % to 114.62 %. Then, the antioxidant activities of different chrysanthemums were investigated, respectively via 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and Ferric Reducing Antioxidant Power (FRAP) assays. The spectrum-effect relationships between nine main components and antioxidant activities were investigated to identify the antioxidant constitutes in chrysanthemums. Meanwhile, H₂ O₂ -induced hepatocyte injury testing showed wide variation in cultivar antioxidant capacity, with Tongchengju (TCJ) producing the best effect (90.32 %), followed by Chuju (CJ; 85.78 %). In addition, the hepatoprotective effects of 8 mainstream varieties were determined by the model of acute alcoholic liver injury. They protected liver from injury by affecting relevant liver function and antioxidant indexes. Huangshangongju (HSG) could decrease aspartate aminotransferase (AST) activity by 39.27 % in liver tissue; Hangju-Fubaiju (HJ-FBJ), Jinsihuangju (JSH), and Chuju (CJ) significantly decreased the malondialdehyde (MDA) content of liver tissue, which reduced by more than 40 %; Jinsihuangju (JSH) of used for tea could double the content of glutathione (GSH) and had the similar effect on superoxide dismutase (SOD) as the positive group, showing significant antioxidant capacity. Therefore, this study confirmed that chrysanthemums are potential resources as antioxidants, functional foods, and medicinal materials. Importantly, it may provide a scientific support for further development and utilization of chrysanthemum, and screen excellent varieties for different demands.

Effects of ammonia on growth performance, lipid metabolism and cecal microbial community of rabbits

This study was designed to investigate the effect of ammonia on growth performance, lipid metabolism and intestinal flora of rabbits. A total of 150 female IRA rabbits (35-days-old) were randomly divided into three groups including 0 ppm (CG), 10 ppm (LAC) and 30 ppm ammonia (HAC) groups for a period of 28 days. The average daily weight gain (ADG) of rabbits was significantly reduced in LAC (-17.11%; p < 0.001) and HAC groups (-17.46%; p < 0.001) as compared with the CG. Serum concentration of high density lipoprotein (HDL) and glucose (Glu) were increased in LAC (+80.95%; +45.99; p < 0.05) and HAC groups (+219.05%; +45.89; p < 0.001), while apolipoprotein A1 (apoA1) was decreased in LAC (-58.49%; p < 0.001) and HAC groups (-36.92%; p < 0.001). The structural integrity of cecum was damaged, and the thickness of mucosa and serosa were significantly decreased in LAC and HAC. The acetate, butyrate and propionate level of cecal chyme were reduced in HAC group (-21.67%; -19.82%; -30.81%; p < 0.05). Microbial diversity and burden of Firmicutes were significantly decreased, while that of pathogenic bacteria, such as Bacteroidetes, Clostridium and Proteobacteria were increased in ammonia treated groups. Spearman's correlation confirmed that burden of Ruminococcaceae_NK4A214_group showed significantly negative correlation with acetic acid (r = -0.67; p < 0.001) while Barnesiellaceae_unclassified showed significantly positive correlation with propionic acid (r = 0.50; p < 0.001). In conclusion, ammonia treatment was responsible for an imbalance of intestinal flora, which affected lipid metabolism and damaged intestinal barrier of rabbits, resulting in low growth performance due to lipid metabolism dysfunction.

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.

Regulation of H2S-induced necroptosis and inflammation in broiler bursa of Fabricius by the miR-15b-5p/TGFBR3 axis and the involvement of oxidative stress in this process

Hydrogen sulfide (H₂S) is an air pollutant, having toxic effects on immune system. Necroptosis has been discussed as a new form of cell death and plays an important role in inflammation. To investigate the mechanism of H₂S-induced immune injury, and the role of microRNAs (miRNAs) in this process, based on the results of high-throughput sequencing, we selected the most significantly changed miR-15b-5p for subsequent experiments. We further predicted and determined the targeting relationship between miR-15b-5p and TGFBR3 in HD11 through miRDB, Targetscan and dual-luciferase, and found that miR-15b-5p is highly expressed in H₂S-induced necroptosis and inflammation. To understand whether miR-15b-5p/TGFBR3 axis could involve in the process of necroptosis and inflammation, we further revealed that the high expression of miR-15b-5p and the knockdown of TGFBR3 can induce necroptosis. Nec-1 treatment enhanced the survival rate of cells. Notably, H₂S exposure induces oxidative stress and activates the TGF-β pathway, which are collectively regulated by the miR-15b-5p/TGFBR3 axis. Our present study provides a new perspective for necroptosis regulated by the miR-15b-5p/TGFBR3 axis and reveals a new form of inflammation regulation in immune diseases.

Cadmium and molybdenum co-exposure triggers autophagy via CYP450s/ROS pathway in duck renal tubular epithelial cells

Cadmium (Cd) and excessive molybdenum (Mo) are detrimental to animals, but the combined nephrotoxic impacts of Cd and Mo on duck are still unclear. To evaluate the combined impacts of Cd and Mo on autophagy via Cytochrome P450s (CYP450s)/reactive oxygen species (ROS) pathway, duck renal tubular epithelial cells were treated with 3CdSO₄·8H₂O (4.0 μM Cd), (NH₄)₆Mo₇O₂₄·4H₂O (500.0 μM Mo), butylated hydroxy anisole (BHA) (100.0 μM) and combination of Cd and Mo or Cd, Mo and BHA for 12 h, and combined cytotoxicity was investigated. The results indicated that Mo or/and Cd induced CYP1A1, CYP1B1, CYP2C9, CYP3A8 and CYP4B1 mRNA levels, decreased superoxide dismutase (SOD), catalase (CAT) activities and glutathione peroxidase (GSH-Px) content, and increased malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) contents. Besides, Mo or/and Cd elevated the number of autophagosome and microtubule-associated protein light chain 3 (LC3) puncta, upregulated mRNA levels of Beclin-1, LC3A, LC3B, Atg5 and adenosine 5'-monophosphate (AMP)-activated protein kinase α1 (AMPKα-1), inhibited Dynein, p62 and mammalian target of rapamycin (mTOR) mRNA levels, increased Beclin-1 and LC3II/LC3I protein levels. Moreover, the changes of these factors in Mo and Cd co-treated groups were more apparent. Additionally, BHA could efficiently alleviate the changes of above these indicators co-induced by Mo and Cd. Overall, these results manifest Cd and Mo co-exposure may synergistically trigger autophagy via CYP450s/ROS pathway in duck renal tubular epithelial cells.

Protective effect of dietary supplementation of Bupleurum falcatum L saikosaponins on ammonia exposure-induced ileum injury in broilers

Ammonia (NH3) at a high concentration has been recognized as a highly poisonous pollutant affecting both air and water quality. NH3, as a stimulus, exerts negative impact on broiler growth and production, but the molecular mechanisms are not clear yet. This study was designed to evaluate the effects of dietary supplementation of Bupleurum falcatum L saikosaponins (SP) on the growth and ileum health status in broilers exposed to NH3. Day-old Arbor Acers broilers (n = 480) were randomly allocated into 1 of 4 treatments. The main factors were dietary SP supplementation (0 or 80 mg/kg of diet) and NH3 challenge (with or without 70 ± 5 ppm NH3). The data of growth, intestinal morphology, and mRNA expression related to ileal function were collected from broilers exposed to NH3 for 7 d. Results showed that NH3 remarkably suppressed growth performance and intestinal development as well as induced biological injuries in the ileum of broilers, resulting from oxidative stress, mucous barrier damage, and immune dysfunction as well as upregulated apoptosis. These negative effects of NH3 were alleviated by the SP supplement. In conclusion, dietary supplementation of SP may be helpful in alleviating the detrimental effects of NH3 on the ileum development in broilers.

In vivo tracing of endogenous salicylic acids as the biomarkers for evaluating the toxicity of nano-TiO2 to plants

Currently, nano-titanium dioxide (nTiO₂) is considered an emerging environmental contaminant. Bottlenecked by the traditional destructive and lethal sampling methods, nTiO₂'s effect in living plants is poorly investigated. Here, in vivo tracing of endogenous salicylic acids at regular intervals was performed by using solid phase microextraction (SPME) technique for evaluating the effects of nTiO₂ on plants. By planting aloe in soil containing varying amounts of nTiO₂, the titanium (Ti) element accumulated in the leaves to concentrations and then reached the maximum of 1.1 ± 0.4 μg/g after nTiO₂ exceeding 0.1 g/kg. The levels of salicylic acid (SA) and acetylsalicylic acid (ASA) were up-regulated upon the exposure to nTiO₂, while were positively correlated to the contents of Ti. Moreover, the increased malondialdehyde, decreased total superoxide dismutase and fluctuated glutathione along with the addition of nTiO₂ demonstrated the oxidative stress caused by nTiO₂. Meanwhile, apparent growth indicators including leaf elongation, plant fresh weight and root development were influenced, which further confirmed the toxicity of nTiO₂ imparted on aloe. This study presents the possibility of using salicylic acids as biomarkers for revealing the toxicity of nTiO₂ on plants in addition to the other biomarkers and biomass data, and the in vivo SPME technique is powerful for their monitoring.

H2S exposure-induced oxidative stress promotes LPS-mediated hepatocyte autophagy through the PI3K/AKT/TOR pathway

Hydrogen sulfide (H₂S), a common air pollutant and toxic gas, is detrimental to organisms and the environment. Exposure to highly concentrated H₂S can induce oxidative stress and autophagy. However, the mechanism underlying the liver damage caused by H₂S has not been identified. Lipopolysaccharide (LPS), the key component of endotoxin, can induce oxidative stress and autophagy. For this experiment, we used one-day-old chickens as model organisms to evaluate the effects of H₂S combined with LPS on oxidative stress and autophagy. The four groups (control group, LPS group, H₂S group and H₂S-LPS group) were observed by electron microscopy, detected by oxidative stress kit, analyzed by quantitative real-time quantitative PCR, and analyzed by Western blot. We found that the activities of antioxidant enzymes (superoxide dismutase, antioxidant glutathione, catalase, and glutathione peroxidase) decreased in the H₂S group compared to those in the control group; however, malondialdehyde levels in the H₂S group increased. Molecular-level studies showed that the expression of genes associated with the PI3K/ AKT/ TOR pathways in the H₂S group decreased, whereas the expression of other autophagy-related genes (Beclin1, ATG5 and the ratio of LC3-II/ LC3-I) increased compared to that in the control group. These findings suggest that H₂S caused oxidative stress and induced autophagy through the PI3K/ AKT/ TOR pathway in chicken liver cells. Additionally, exposure to H₂S aggravated LPS-induced oxidative stress and autophagy injury. Capsule: Aerial exposure to H₂S can cause oxidative stress in chicken livers and induce autophagy through the PI3K/AKT/TOR pathway, and can aggravate LPS-induced oxidative stress and autophagy.

Exposure to the environmental pollutant ammonia causes changes in gut microbiota and inflammatory markers in fattening pigs

Ammonia (NH₃) is a major pollutant in livestock houses and atmospheric environment. It has been demonstrated that NH₃ can cause a series of damage to animals and human. However, toxicity evaluation of NH₃ on farm animals was rarely reported, especially in the intestinal microflora. Therefore, in this study, twenty-four 125-day-old fattening pigs were randomly divided into 4 groups: control group, NH₃ group (88.2 mg m^-3 < NH₃ concentration < 90.4 mg m^-3), Se group (Se content: 0.5 mg kg^-1), and NH₃ + Se group (88.2 mg m^-3 < NH₃ concentration < 90.4 mg m^-3, Se content: 0.5 mg kg^-1), and the effects of NH₃ and L-Selenomethionine on the microbiota composition in the jejunum and the levels of inflammatory markers in feces of fattening pigs were examined by 16S rDNA and ELISA, respectively. Our results showed that the content of Matrix metalloproteinase-9 (MMP-9), Myeloperoxidase (MPO), Lactoferrin (LTF) and Calprotectin in the ammonia group (A group) were significantly elevated compared to the control group, and the content of MMP-9, MPO, LTF and Calprotectin in the A + Se group were significantly reduced. A significant difference in microbiota composition in the phylum, class, family and genus levels was found in the A group and the NH₃ + Se group. There was a negative correlation between Streptococcus and Calprotectin. Our results indicated that excessive NH₃ inhalation could cause changes in inflammatory markers and beta diversity of intestinal microflora in fattening pigs. We found there was a positive correlation between MPO and Pseudomonas. In addition, we first proposed that L-Selenomethionine could improve the imbalance of microbial flora and the inflammatory injury caused by NH₃. Changes in intestinal microflora and inflammatory markers can be used as important indicators to evaluate NH₃ toxicity, and studying changes in intestinal microflora is also an important mechanism to reveal NH₃ toxicity.

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.

Mixed plasticizers aggravated apoptosis by NOD2-RIP2-NF-κB pathway in grass carp hepatocytes

The wide application of plastics led to the wide exposure of plasticizers to the environment. As a new environmental pollutant, plasticizers' toxicity researches were far from enough in fish. To further explore these mechanisms, we used two common plasticizers (Diethylhexyl phthalate (DEHP) and dibutyl phthalate (DBP) expose to grass carp hepatocytes (L8824). The results showed that the mRNA levels of NOD2-RIP2-NF-κB signal pathway and its downstream inflammatory genes were significantly increased compared to those in control group. Then, the levels of mRNAs and proteins of apoptosis markers were changed, and hepatocytes apoptosis was induced. After DBP and DEHP exposure together, there were higher levels of inflammatory factors and the proportion of apoptotic cells. After NOD2 inhibitor treatment, the phenomena mentioned above were obviously alleviated. We conclude that DBP and DEHP exposure at least partially activated the NOD2-RIP2-NF-κB signal pathway in grass carp hepatocytes, and caused inflammation and apoptosis. In terms of hepatotoxicity, there was synergistic relationship between DBP and DEHP. In addition, we put forward new views on the use of plasticizers: select low toxicity plasticizers, then reduce the types of plasticizers used and reduce the high toxicity level of mixed plasticizers.

Effects of astragalus polysaccharide on intestinal inflammatory damage in goslings infected with gosling plague

1. This study explored the effects of Astragalus membranaceus polysaccharide (APS) on intestinal inflammatory damage of goslings infected with parvovirus ('gosling plague').2. A total of 90 healthy goslings were randomly divided into three groups; control, infected or APS treated, respectively. Goslings in the infection and APS treatment groups were inoculated with 0.3 ml allantoic fluid containing goose parvovirus (ELD₅₀ = 1 × 10³/0.3 ml) by intramuscular injection and the control group were injected with saline (0.3 ml) twice a day for 15 days.3. Blood serum and the jejunum were collected at 5, 10 and 15 days after the start of the experiment to detect the activities of SOD and GSH-Px, levels of MDA, sIgA, IL-1β, IL-6 and TNF-α, the mRNA expression of IL-1β, IL-6, LITAF, NF-κB, COX-2 and PGE2, pathological damage in the jejunum and serum IgG, IgM, C3, C4, IFN-γ levels.4. After APS treatment, SOD and GSH-Px activities increased, MDA content decreased; sIgA, IL-1β, IL-6 and TNF-α protein content, and IL-1β, IL-6, LITAF, NF-κB, COX-2 and PGE2 mRNA expression decreased in the jejunal tissue, serum IgG, IgM, C3, C4, IFN-γ significantly increased and pathological damage of jejunum significantly improved.5. In conclusion, APS reduced intestinal inflammatory damage in goslings infected with parvovirus by improving the immune and antioxidant functions of goslings.

Inhibition of autophagy enhances cadmium-induced apoptosis in duck renal tubular epithelial cells

Increasing evidence indicates autophagy and apoptosis are involved in the toxicity mechanism of heavy metals. Our previous studies showed that cadmium (Cd) could induce autophagy and apoptosis in duck kidneys in vivo, nevertheless, the interaction between them has yet to be elucidated. Herein, the cells were either treated with 3CdSO₄·8H₂O (0, 1.25, 2.5, 5.0 μM Cd) or/and 3-methyladenine (3-MA) (2.5 μM) for 12 h and the indictors related autophagy and apoptosis were detected to assess the correlation between autophagy and apoptosis induced by Cd in duck renal tubular epithelial cells. The results demonstrated that Cd exposure notably elevated intracellular and extracellular Cd contents, the number of autophagosomes and LC3 puncta, up-regulated LC3A, LC3B, Beclin-1, Atg5 mRNA levels, and Beclin-1 and LC3II/LC3I protein levels, down-regulated mTOR, p62 and Dynein mRNA levels and p62 protein level. Additionally, autophagy inhibitor 3-MA decreased Beclin-1, LC3II/LC3I protein levels and increased p62 protein level. Moreover, co-treatment with Cd and 3-MA could notably elevate Caspase-3, Cyt C, Bax, and Bak-1 mRNA levels, Caspase-3 and cleaved Caspase-3 protein levels, and cell apoptotic rate as well as cell damage, decreased mitochondrial membrane potential (MMP), Bcl-2 mRNA level and the ratio of Bcl-2 to Bax compared to treatment with Cd alone. Overall, these results indicate Cd exposure can induce autophagy in duck renal tubular epithelial cells, and inhibition of autophagy might aggravate Cd-induced apoptosis through mitochondria-mediated pathway.

Proteomics analysis of lung reveals inflammation and cell death induced by atmospheric H2S exposure in pig

Hydrogen sulfide (H₂S) is a popular toxic environmental gas and industrial pollutant, which can be harmful to multiple organ systems of both human and livestock, especially to the respiratory system. However, the injury mechanism of H₂S exposure to lung remains poorly understood. In this study, pig lung was selected as a H₂S exposure model for the first time. We first examined the histological damage and the mRNA expression of pro-inflammatory genes of lung in pigs exposed to H₂S. Histopathology change and increased mRNA level of pro-inflammatory cytokines demonstrated that H₂S exposure indeed induced inflammatory injury in the porcine lung. We then performed TMT-based quantitative proteomics analysis to probe the injury molecular mechanism. The proteomics results showed that 526 proteins have significant changes in abundance between control and H₂S treated swine. Further validation analysis of some H₂S responsive proteins using both Real-time quantitative PCR and western blotting demonstrated that proteomics data are reliable. KEGG pathway analysis revealed that these proteins were involved in antigen processing and presentation, complement and coagulation cascade, IL-17 signaling pathway, ferroptosis and necroptosis. Our data suggest that H₂S exposure induced immune suppression, inflammatory response and cell death. These findings provide a new insight into the complexity mechanisms of H₂S induced lung injury, and offer therapeutic potential as drug targets with a view towards curing the intoxication caused by H₂S.

Selenomethionine alleviates LPS-induced chicken myocardial inflammation by regulating the miR-128-3p-p38 MAPK axis and oxidative stress

Selenium is closely related to the occurrence of heart disease, and an appropriate amount of selenium can alleviate inflammatory changes caused by various factors. Lipopolysaccharide (LPS), as a specific component of the cell wall of Gram-negative bacteria, is often used to construct various inflammatory models. In order to explore the effect of selenium on LPS-induced myocardial inflammation in chickens, we chose 4-month-old laying hens to be fed with a selenium-rich diet containing 0.5 g kg-1 Se, and injected LPS into the abdominal cavity at the age of 8 months to establish an inflammation model. We observed the myocardial tissue lesions by light microscopy, and detected miR-128-3p, p38MAPK, and NF-κB pathway-associated inflammatory factors and Th1/Th2 related factors by qRT-PCR and Western blot. The results showed that LPS stimulation inhibited miR-128-3p, which increased the expression of p38MAPK and NF-κB, while the expression of TNF-α, IL-1, PTGE, COX-2 and iNOS increased. Additionally, the expression of IL-4 and IL-6 increased and IFN-γ decreased, suggesting an imbalance of Th1/Th2. We also found that LPS treatment not only increased the content of H2O2 and MDA in the myocardium, but also increased the expression of HSP60, HSP70 and HSP90, while the activity of SOD, GPX and CAT and the content of GSH decreased. Interestingly, the addition of selenium can alleviate the changes in the above indicators. Finally, we concluded that selenium inhibits the occurrence of oxidative stress and ultimately alleviates myocardial inflammation induced by LPS through the miR-128-3p-p38MAPK-NF-κB pathway.

Cadmium-induced oxidative stress promotes apoptosis and necrosis through the regulation of the miR-216a-PI3K/AKT axis in common carp lymphocytes and antagonized by selenium

Cadmium (Cd) is a primary environmental pollutant which causes the immune dysfunction of aquatic animals. MicroRNAs (miRNAs) play a key role in programmed necrosis and apoptosis of immune organs. Selenium (Se), known as an important element, can antagonize Cd toxicity in birds, but the impact of Se on common carps (Cyprinus carpio) has not been reported. To investigate the Cd-induced immunotoxicity mechanism mediated by miR-216a in splenic lymphocytes of common carp and antagonized by Se, we extracted lymphocytes from the spleen and divided them into control group, Se group (10^-6 mol/L of Na₂SeO₃), Se + Cd group and Cd group (4 × 10^-5 mol/L of CdCl₂). After 6 h of incubation, AO/EB staining, Flow cytometry, qPCR and Western blot were performed. The results showed that Cd exposure caused the apoptosis (BAX, Bcl-2, Caspase 3, Caspase 9) and programmed necrosis (RIP, RIP3, MLKL) in lymphocytes, increased the expression of CYP enzymes, glycometabolism-related enzymes and production of ROS, while irritated the oxidative stress (MDA, SOD, CAT and GSH-PX), upregulated the expression of miR-216a which attenuated the levels of PI3K. However, those variations were apparently mitigated in the Se + Cd group. In short, we have proven that Cd activates oxidative stress and miR-216a-PI3K/AKT axis disorder, thus promoting apoptosis and necrosis in lymphocytes. Moreover, Se can antagonize Cd-triggered apoptosis and necrosis in lymphocytes.

Itraconazole exerts anti-liver cancer potential through the Wnt, PI3K/AKT/mTOR, and ROS pathways

Hepatocellular carcinoma (HCC) is one of the most common cancers with the highest morbidity and mortality. It is necessary to develop new anti-liver cancer drugs. Itraconazole is a popular systemic anti-fungal drug with a strong anti-tumor effect. However, so far, it is not clear whether itraconazole has specific anti-tumor effect on liver cancer. The purpose of this study was to investigate itraconazole resistant effect of liver cancer and to explore its potential anti-cancer mechanism. The effect of itraconazole on the proliferation of liver cancer cells was studied with MTT assay. Flow cytometry was used to determine the effect of itraconazole on apoptosis, cell cycle distribution, changes in intracellular reactive oxygen species (ROS) and mitochondrial membrane potential (MMP). In addition, after DAPI staining, nuclear morphological changes were observed under the fluorescent microscope, and the release of lactate dehydrogenase (LDH) was measured using the microplate reader. Finally, the expressions of proteins related to the anti-tumor signaling pathway were determined by Western blotting. The results showed that itraconazole significantly inhibited the proliferation of HepG2 and Bel-7405 cells. In addition, the data showed that itraconazole induced apoptosis in HepG2 cells, increased the production of ROS, blocked cell cycle, and decreased MMP. Furthermore, itraconazole inhibited HCC cell growth and promoted apoptosis through the Hh, Wnt/catenin, AKT/mTOR/S6K, ROS and death receptor pathways. Finally, we come to the conclusion that itraconazole exerts anti-liver cancer effect, and has potential for use as a new drug for liver cancer in clinic.

Copper induces oxidative stress with triggered NF-κB pathway leading to inflammatory responses in immune organs of chicken

Copper (Cu) is a necessary trace mineral due to its biological activity. Excessive Cu can induce inflammatory response in humans and animals, but the underlying mechanism is still unknown. Here, 240 broilers were used to study the effects of excessive Cu on oxidative stress and NF-κB-mediated inflammatory responses in immune organs. Chickens were fed with diet containing different concentrations of Cu (11, 110, 220, and 330 mg of Cu/kg dry matter). The experiment lasted for 49 days. Spleen, thymus, and bursa of Fabricius (BF) on day 49 were collected for histopathological observation and assessment of oxidative stress status. Additionally, the mRNA and protein levels of NF-κB and inflammatory cytokines were also analyzed. The results indicated that excess Cu could increase the number and area of splenic corpuscle as well as the ratio of cortex and medulla in thymus and BF. Furthermore, excessive Cu intake could decrease activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px); but increase contents of malondialdehyde (MDA), TNF-α, IL-1, IL-1β; up-regulate mRNA levels of TNF-α, IFN-γ, IL-1, IL-1β, IL-2, iNOS, COX-2, NF-κB and protein levels of TNF-α, IFN-γ, NF-κB, p-NF-κB in immune organs. In conclusion, excessive Cu could cause pathologic changes and induce oxidative stress with triggered NF-κB pathway, and might further regulate the inflammatory response in immune organs of chicken.

The involvement of miR-6615-5p/Smad7 axis and immune imbalance in ammonia-caused inflammatory injury via NF-κB pathway in broiler kidneys

Ammonia (NH₃), a toxic gas, has deleterious effects on chicken health in intensive poultry houses. MicroRNA can mediate inflammation. The complex molecular mechanisms underlying NH₃ inhalation-caused inflammation in animal kidneys are still unknown. To explore the mechanisms, a broiler model of NH₃ exposure was established. Kidney samples were collected on day 14, 28, and 42, and meat yield was evaluated on day 42. We performed histopathological examination, detected miR-6615-5p and mothers against decapentaplegic homolog 7 (Smad7), and determined inflammatory factors and cytokines in kidneys. The results showed that excess NH₃ reduced breast weight and thigh weight, which indicated that excess NH₃ impaired meat yield of broilers. Besides, kidney tissues displayed histopathological changes after NH₃ exposure. Meanwhile, the increases of inducible nitric oxide synthase (iNOS) activity and nitric oxide content were obtained. The mRNA and protein expression of inflammatory factors, including nuclear factor-κB (NF-κB), cyclooxygenase-2, prostaglandin E synthases, and iNOS increased, indicating that NF-κB pathway was activated. T-helper (Th) 1 and regulatory T (Treg) cytokines were downregulated, whereas Th2 and Th17 cytokines were upregulated, suggesting the occurrence of Th1/Th2 and Treg/Th17 imbalances. In addition, we found that Smad7 was a target gene of miR-6615-5p in chickens. After NH₃ exposure, miR-6615-5p expression was elevated, and Smad7 mRNA and protein expression were reduced. In summary, our results suggest that NH₃ exposure negatively affected meat yield; and miR-6615/Smad7 axis and immune imbalance participated in NH₃-induced inflammatory injury via the NF-κB pathway in broiler kidneys. This study is helpful to understand the mechanism of NH₃-induced kidney injury and is meaningful to poultry health and breed aquatics.

The Effect of Selenium on CYP450 Isoform Activity and Expression in Pigs

Selenium is an essential nutrient in diets; however, the effects of selenium on enzyme metabolic activation are not currently clear. Cytochromes P450 (CYP450) are major phase I metabolic enzymes involved in the biotransformation of xenobiotics and endogenous compounds to form electrophilic reactive metabolites. To investigate the effect of selenium on CYP450 isoform activity, the Landrace pigs were divided into three groups: the control group (containing Se 0.15 mg/kg), the Se-deficient group (Se 0.03 mg/kg), and the Se-supply group (Se 0.35 mg/kg). After 1 week of administration, a mixed solution (20 mg/kg of dextromethorphan, phenacetin, chlorzoxazone, and 10 mg/kg of testosterone in a CMC-Na solution) was intravenously injected into all pigs. The mixed solution content and pharmacokinetic parameters were assayed by HPLC and DAS, respectively. To investigate the effect of selenium on CYP450 isoform expression, RNA-Seq analysis, Western boltting, and qPCR were used. Results showed that Se-supply group significantly increased the activity and expression of CYP1A2 and CYP2D25, and decreased CYP3A29. Se-deficient group decreased the activity of CYP1A2, CYP2D25, and CYP2E1. These results demonstrated that selenium content affecting the activity or expression of the CYP450 isoform may lead to a food-drug interaction.

Environmental contaminant ammonia triggers epithelial-to-mesenchymal transition-mediated jejunal fibrosis with the disassembly of epithelial cell-cell contacts in chicken

Ammonia (NH₃) is an environmental contaminant that is causing increasing problems with human and animal health due to the development of poultry industry. There are limited studies on the effect of NH₃ inhalation toxicity on the intestinal tract of animals, and underlying molecular mechanisms remain unclear. In the present study, we established a chicken model of NH₃ aspiration-induced injury for 42 days and observed histopathological changes of the jejunum. Tandem mass tag-based quantitative proteomic analysis was applied to investigate changes in the protein profile in the jejunum tissue of chickens that were exposed to NH₃. Overall, 48 significantly differentially expressed proteins (DEPs) were identified. GO and KEGG analyses revealed that most DEPs were closely related to epithelial-to-mesenchymal transition (EMT), cell-cell junctions, and fibrosis-related factors. Regarding fibrosis, type I collagen and fibronectin were significantly increased. With respect to EMT, epithelial marker proteins (such as E-cadherin and keratin) were repressed, while mesenchymal marker proteins (such as vimentin) were activated. Loss of epithelial cell-cell junctions (such as tight junctions, adherens junctions and desmosomes) were observed. Additionally, overexpression of transforming growth factor-beta (TGF-β) may play a key role in the EMT process and fibrosis. Taken together, these findings suggested that NH₃ triggered the EMT and disassembly of epithelial cell-cell contacts, resulting in jejunal fibrosis that was mediated by TGF-β in chickens. The results of our study will contribute to provide a technical reference regarding the research methods of intestinal toxicity of NH₃ and have largely regulatory implications for ecological risk assessment of human health.

Protective effect of quercetin on rat testes against cadmium toxicity by alleviating oxidative stress and autophagy

Cadmium (Cd), a highly toxic heavy metal, adversely affects human and animal health. Quercetin (Que) is a kind of flavonoid that can protect many tissues from the toxic effect of heavy metals. Although many studies have explored the adverse effects of cadmium on rats and other animals, the mechanism of Cd-induced testicular autophagy and the antagonistic effect of Que on cadmium remain unclear. In this study, Sprague-Dawley rats were treated with Cd, Que or Cd, and Que supplements to explore the mechanisms of Que-alleviated testis injury caused by Cd exposure. The rat body weight and relative testicular weight were measured. Morphological changes in testes and indices of oxidative stress were also examined. The expression levels of autophagy-related genes were detected as well. Results showed that Cd decreased the rat body weight and relative testicular weight and induced pathological changes in testes. Conversely, Que alleviated these changes. We also found that Cd increased the malondialdehyde content and decreased the contents of total superoxide dismutase, glutathione peroxidase, catalase, and glutathione. Moreover, the protein expression levels of P62 and LC3-II increased under Cd exposure conditions. Conversely, Que obviously alleviated these toxic activities induced by Cd. Overall, this study showed that Cd accumulated in rat testes, leading to oxidative stress and autophagy. Que can reduce cadmium toxicity by reducing oxidative stress and inhibiting autophagy. The specific mechanism of Que antagonizing Cd toxicity can provide new insights into countering cadmium toxicity.

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.

Ameliorative Effect of Selenomethionine on Cadmium-Induced Hepatocyte Apoptosis via Regulating PI3K/AKT Pathway in Chickens

Selenium (Se) is a trace element for human and animal health. Cadmium (Cd) is a known human carcinogen. The effects of Cd on the environment and humans are well known. Because chickens are at the top of the food chain, it is a good experimental animal model for assessing heavy metal toxicity and its potential threat to humans. Selenomethionine (Se-met) is a suitable form for nutritional Se supplementation. Therefore, the toxicity of Cd to the chicken liver and the antagonistic effects of Se-met on Cd were examined at the molecular level in the present study. The results showed that oxidative stress indicators (apoptosis-related genes, P13K/AKT pathway-related genes, and heat shock proteins (HSPs)-related genes) in the Cd group have changed significantly, indicating Cd induced hepatocyte stress and apoptosis. Interestingly, the changes in oxidative stress indicators (apoptosis-related genes, P13K/AKT pathway-related genes, and HSPs-related genes) in the Cd-Se-met group were mitigated compared with the control group. Our results indicated that Cd can induce hepatocyte apoptosis and stress in the chickens. Se-met has an ameliorative effect on Cd-induced apoptosis of chicken hepatocyte by regulating PI3K/AKT pathway. Our findings will provide a new insight for better understanding of the detoxification function of Se-met to heavy metals.