Ammonia inhalation-mediated mir-202-5p leads to cardiac autophagy through PTEN/AKT/mTOR pathway

Waterborne ammonia toxicity damages crustacean hemocytes via lysosome-dependent autophagy: A case study of swimming crabs Portunus trituberculatus

Waterborne ammonia is a threat to animal health and its accumulation is typical of aquatic ecosystems. Autophagy serves as a safeguard of intracellular homeostasis, yet its role in maintaining the health of hemocytes, the master regulators of crustacean immunity, remains unclear. Herein, the swimming crab (Portunus trituberculatus) is employed as a case study to illustrate the impact of ammonia on hemocyte health via autophagy. This study showed the occurrence of abnormal cellular structure and significant accumulation of malondialdehyde (MDA) and reactive oxygen species (ROS) (P < 0.05), demonstrating that severe ammonia stress can damage hemocytes. This was accompanied by significant increase of autophagy hemocytes fraction and apoptosis (P < 0.05). Meanwhile, there was a significant increase in the expression of Beclin1 and microtubule-associated protein 1 light chain 3 (LC3-II) (P < 0.05). This suggests an ammonia-induced autophagy initiation. However, ammonia stress significantly decreased lysosomal fluorescence intensity (P < 0.05) and expression of the marker gene lysosomal-associated membrane protein 1 (LAMP1) (P < 0.05). These imply an ammonia-induced repression of lysosome-dependent autophagy degradation, which may underlie the pronounced increase in apoptosis (P < 0.05). After the administration of the autophagy activator rapamycin (Rap), rather than the inhibitor 3-Methyladenine (3-MA), the levels of apoptosis, ROS and the fraction of autophagic cells were significantly decreased (P < 0.05), demonstrating a mitigation of the ammonia-induced cell damage through lysosome-dependent autophagy degradation. This study sheds light on how crustaceans respond to ammonia exposure by demonstrating the significance of lysosome-dependent autophagy in maintaining hemocyte health.

Co-exposure to ammonia and lipopolysaccharide-induced impaired energy metabolism via the miR-1599/HK2 axis and triggered autophagy, ER stress, and apoptosis in chicken cardiomyocytes

Ammonia (NH3) and lipopolysaccharide (LPS), common pollutants in poultry farming environments, pose significant health risks by disrupting cellular processes. Although previous studies have demonstrated the individual effect of NH3 or LPS on human and animal health, the mechanisms underlying their combined impact on chicken heart tissue remain poorly understood. In this study, we established a chicken cardiotoxicity model to investigate the effects of NH3 and/or LPS exposure on energy metabolism, autophagy, endoplasmic reticulum (ER) stress, and apoptosis in cardiomyocytes. Our findings indicated that exposure to NH3 or/and LPS reduced ATPase activity and ATP content, led to the downregulation of HK2, PK, PDHX, and SDH, and upregulation of AMPK, resulting in impaired energy metabolism in chicken cardiomyocytes. Additionally, we found the gga-miR-1599/HK2 axis as a key regulator involved in NH3 or/and LPS-induced energy metabolism impairment. The impairment in energy metabolism activated the AMPK/mTOR pathway, which subsequently triggered autophagy, evidenced by the upregulation of Beclin, LC3-I, and LC3-II. Furthermore, decreased mTOR expression induced ER stress, as indicated by the upregulation of key markers such as ATF6, GRP78, IRE1, and PERK. ER stress, in turn, increased CHOP expression, which downregulated Bcl-2 and upregulated Bim, resulting in elevated levels of Bax, caspase-9, and caspase-3, ultimately triggering apoptosis. This study provides valuable insights into the mechanisms of NH3 and LPS co-exposure on poultry heart tissue and identifies potential molecular targets for mitigating these adverse effects.

The mTOR Signaling Pathway: Key Regulator and Therapeutic Target for Heart Disease

Heart disease, including myocardial infarction, heart failure, cardiac hypertrophy, and cardiomyopathy, remains a leading cause of mortality worldwide. The mammalian target of rapamycin (mTOR) is a centrally regulated kinase that governs key cellular processes, including growth, proliferation, metabolism, and survival. Notably, mTOR plays a pivotal role in cardiovascular health and disease, particularly in the onset and progression of cardiac conditions. In this review, we discuss mTOR's structure and function as well as the regulatory mechanisms of its associated signaling pathways. We focus on the molecular mechanisms by which mTOR signaling regulates cardiac diseases and the potential of mTOR inhibitors and related regulatory drugs in preventing these conditions. We conclude that the mTOR signaling pathway is a promising therapeutic target for heart disease.

Golgi apparatus regulated pyroptosis through the miR-32-5p/Golga7/NLRP3 axis in chicken splenic lymphocytes exposure to ammonia

Ammonia, a common toxic gas, posed a hazard to both human and chickens. The Golgi apparatus, an essential organelle, helped maintain the internal environment of the organism and supported the protein foundation for the endoplasmic reticulum to be involved in pyroptosis. Thus, the Golgi apparatus has garnered significant attention. The purpose of our research was to explore the mechanisms of Golgin A7 (Golga7) involved in pyroptosis after chicken exposure to ammonia. To reach our goal, we first created an in vitro ammonia model to study the effect of ammonia on chicken splenic lymphocyte pyroptosis. Then, leveraging this model, we established Golga7 and miR-32-5p knockdown and overexpression models to investigate their roles in ammonia-induced pyroptosis. We found the ultrastructural changes in the nucleus, Golgi apparatus, and mitochondria of chicken splenic lymphocytes exposure to ammonia. The damage of mitochondria increased the level of Reactive Oxygen Species (ROS), which caused the down-regulation of miR-32-5p. The miR-32-5p inhibitor increased the expression of Golga7 and pyroptosis-related genes (NOD-like receptor protein 3 (NLRP3), Cysteine aspartase-1 (Caspase-1), Golgin A3 (Golga3), Nuclear Factor-kappa B (NF-κB), and Tumor Necrosis Factor-alpha (TNF-α)), which induced the pyroptosis, but when miR-32-5p mimic/si-Golga7 (Golga7 inhibitor) was utilized, these effects were reduced. Our research demonstrated that miR-32-5p/Golga7 regulated NLRP3 involving in the pyroptosis of chicken splenic cells exposed to ammonia. Our study provided a valuable foundation for the prevention and treatment chickens ammonia poisoning in the livestock production.

Identification and functional analysis of circular RNA expression profiles associated with ammonia exposure in chicken lungs

Ammonia acts as a detrimental atmospheric pollutant, posing a sever threat to respiratory tract health and causing lung injury in humans and animals. Circular RNAs (circRNAs) are a distinctive class of non-coding RNA generated by back-splicing of linear RNA, implicated in various biological processes. However, their role in the immune response of chicken lungs to ammonia exposure remains unclear. In this study, we examined the expression profiles of circRNAs in chicken lungs under ammonia stimulation. In total, 61 differentially expressed (DE) circRNAs were identified between the ammonia exposure and control groups, including 17 up-regulated and 44 down-regulated circRNAs. The source genes of these DE circRNAs were predominantly enriched in Influenza A, SNARE interactions in vesicular transport, and Notch signaling pathway. Notably, nine DE circRNAs (circNBAS, circMTIF2, circXPO1, circSNX24, circRAB11A, circARID3B, circUSP54, circPPARA, and circERG) were selected for validation the reliability and authenticity of RNA-seq data. Results showed the back-splicing circular structure, as well as the reliability and accuracy of RNA-seq data in quantifying circRNA expression, as the RT-qPCR results were in agreement with the RNA-seq data. Moreover, we constructed the circRNA-miRNA-mRNA regulatory networks and identified several regulatory networks in chicken lungs under ammonia stimulation, including circRAB11A-gga-miR-191b-3p-BRD2 and circARID3B-gga-miR-1696-CKS2. Taken together, our study delineates the circRNA expression profile and their potential roles in the immune response of chicken lungs to ammonia exposure. These findings offer insights into molecular mechanisms that may mitigate diseases associated with ammonia induced respiratory tract pollution in humans and animals.

Analysis revealed the molecular mechanism of oxidative stress-autophagy-induced liver injury caused by high alkalinity: integrated whole hepatic transcriptome and metabolome

Introduction

High-alkalinity water is a serious health hazard for fish and can cause oxidative stress and metabolic dysregulation in fish livers. However, the molecular mechanism of liver damage caused by high alkalinity in fish is unclear.

Methods

In this study, 180 carp were randomly divided into a control (C) group and a high-alkalinity (A25) group and were cultured for 56 days. High-alkalinity-induced liver injury was analysed using histopathological, whole-transcriptome, and metabolomic analyses.

Results

Many autophagic bodies and abundant mitochondrial membrane damage were observed in the A25 group. High alkalinity decreased superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activity and the total antioxidant capacity (T-AOC) and increased the malondialdehyde (MDA) content in liver tissues, causing oxidative stress in the liver. Transcriptome analysis revealed 61 differentially expressed microRNAs (miRNAs) and 4008 differentially expressed mRNAs. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that mammalian target of rapamycin (mTOR), forkhead box O (FoxO), mitogen-activated protein kinase (MAPK), and the autophagy signalling pathway were the molecular mechanisms involved. High alkalinity causes oxidative stress and autophagy and results in autophagic damage in the liver. Bioinformatic predictions indicated that Unc-51 Like Kinase 2 (ULK2) was a potential target gene for miR-140-5p, demonstrating that high alkalinity triggered autophagy through the miR-140-5p-ULK2 axis. Metabolomic analysis revealed that the concentrations of cortisol 21-sulfate and beta-aminopropionitrile were significantly increased, while those of creatine and uracil were significantly decreased.

Discussion

The effects of high alkalinity on oxidative stress and autophagy injury in the liver were analysed using whole-transcriptome miRNA-mRNA networks and metabolomics approaches. Our study provides new insights into liver injury caused by highly alkaline water.

Exploring the metabolic implications of blue light exposure during daytime in rats

Excessive exposure to light is a global issue. Artificial light pollution has been shown to disrupt the body's natural circadian rhythm. To investigate the impacts of light on metabolism, we studied Sprague-Dawley rats chronically exposed to red or blue light during daytime or nighttime. Rats in the experimental group were exposed to extended light for 4 hours during daytime or nighttime to simulate the effects of excessive light usage. Strikingly, we found systemic metabolic alterations only induced by blue light during daytime. Furthermore, we conducted metabolomic analyses of the cerebrospinal fluid, serum, heart, liver, spleen, adrenal, cerebellum, pituitary, prostate, spermatophore, hypothalamus and kidney from rats in the control and blue light exposure during daytime. Significant changes in metabolites have been observed in cerebrospinal fluid, serum, hypothalamus and kidney of rats exposed to blue light during daytime. Metabolic alterations observed in rats encompassing pyruvate metabolism, glutathione metabolism homocysteine degradation, phosphatidylethanolamine biosynthesis, and phospholipid biosynthesis, exhibit analogous patterns to those inherent in specific physiological processes, notably neurodevelopment, cellular injury, oxidative stress, and autophagic pathways. Our study provides insights into tissue-specific metabolic changes in rats exposed to blue light during the daytime and may help explain potential mechanisms of photopathogenesis.

In-house ammonia induced lung impairment and oxidative stress of ducks

Ammonia (NH3) is a toxic gas that in intensive poultry houses, damages the poultry health and induces various diseases. This study investigated the effects of NH3 exposure (0, 15, 30, and 45 ppm) on growth performance, serum biochemical indexes, antioxidative indicators, tracheal and lung impairments in Pekin ducks. A total of 288 one-day-old Pekin male ducks were randomly allocated to 4 groups with 6 replicates and slaughtered after the 21-d test period. Our results showed that 45 ppm NH3 significantly reduced the average daily feed intake (ADFI) of Pekin ducks. Ammonia exposure significantly reduced liver, lung, kidney, and heart indexes, and lowered the relative weight of the ileum. With the increasing of in-house NH3, serum NH3 and uric acid (UA) concentrations of ducks were significantly increased, as well as liver malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPX-Px) contents. High NH3 also induced trachea and lung injury, thereby increasing levels of tumor necrosis factor-α (TNF-α) and interleukin-4 (IL-4) in the lung, and decreasing the mRNA expressions of zonula occludens 1 (ZO-1) and claudin 3 (CLDN3) in the lung. In conclusion, in-house NH3 decrease the growth performance in ducks, induce trachea and lung injuries and meanwhile increase the compensatory antioxidant activity for host protection.

Enhanced photocatalytic ammonia oxidation activity and nitrogen selectivity over Ag/AgCl/N-TiO2 photocatalyst

The removal of ammonia (NH3) emitted from agricultural and industrial activities is of great significance to protect human health and ecological environment. Photocatalytic NH3 oxidation to N2 under mild conditions is a promising strategy. However, developing visible light photocatalysts for NH3 oxidation is still in its infancy. Here, we fabricate N-TiO2 and Ag/AgCl/N-TiO2 photocatalysts by sol-gel and photodeposition methods, respectively. The introduction of N not only endows TiO2 with visible light response (absorption edge at 460 nm) but also results in the formation of heterophase junction (anatase and rutile). Thus, N-TiO2 shows 2.0 and 1.8 times higher than those over anatase TiO2 and commercial TiO2 for NH3 oxidation under full spectrum irradiation. Meanwhile, surface modification of Ag can simultaneously enhance visible light absorption (generating localized surface plasmon resonance effect) and charge separation efficiency. Therefore, the photocatalytic activity of Ag/AgCl/N-TiO2 is further improved. Furthermore, the presence of N and Ag also enhances the selectivity of N2 product owing to the change of reaction pathway. This work simultaneously regulates photocatalytic conversion efficiency and product selectivity, providing some guidance for developing highly efficient photocatalysts for NH3 elimination.

Luteolin enhanced antioxidant capability and induced pyroptosis through NF-κB/NLRP3/Caspase-1 in splenic lymphocytes exposure to ammonia

During feeding process in intensive chicken farms, the prolonged exposure of chickens to elevated level of ammonia leads to substantial economic losses within poultry farming industry. Luteolin (Lut), known as its anti-inflammatory and antioxidant properties, possesses the ability to eliminate free radicals and enhance the activities of antioxidant enzymes, thus rendering it highly esteemed in production. The objective of this study was to examine the effects of Lut on antioxidant and anti-inflammatory responses of chicken splenic lymphocytes exposed to ammonia. In order to achieve this, we have replicated a protective model involving Lut against ammonia exposure in chicken splenic lymphocytes. The findings of the study indicated that Lut mitigated the elevation of lactate dehydrogenase (LDH), malondialdehyde (MDA), and reactive oxygen species (ROS) induced by ammonia poisoning. Additionally, Lut demonstrated an increase in the expression of antioxidant enzymes, namely superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Furthermore, Lut exhibited a protective effect on cell morphology and ultrastructure following exposure to ammonia. Moreover, Lut exhibited a reduction in the expression of heat shock proteins (HSPs) and inflammatory cytokines, which were found to be highly expressed in splenic lymphocytes after ammonia exposure. Additionally, Lut demonstrated the ability to inhibit the overexpression of pyroptosis-related genes and proteins (NLRP3 and Caspase-1) in splenic lymphocytes following ammonia exposure. Lut exerted an antioxidant effect on lymphocytes, counteracting elevated levels of oxidative stress following exposure to ammonia. Additionally, Lut had the potential to modulate the expression of HSPs, suppressed the inflammatory response subsequent to ammonia exposure, and influenced the expression of NLRP3 and Caspase-1, thereby mitigating pyroptosis induced by ammonia exposure. The exploration of this subject matter can elucidate the protective properties of Lut against NH4Cl-induced damage in chicken splenic lymphocytes, while also offer insights and experimental groundwork for the utilization of natural therapeutics in animal husbandry to prevent and treat ammonia-related conditions.

Macrophage-derived exosomal microRNAs promote metastasis in pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a highly invasive disease that can metastasize to distant organs such as the lung and liver. However, the exact mechanisms underlying PDAC metastasis remain unclear. Tumor-associated macrophages (TAMs) have been shown to play a critical role in cancer initiation, progression, outgrowth, and metastasis, likely through their interaction with cancer cells via extracellular vesicles known as exosomes. However, the precise mechanisms of this interaction are not fully understood.

METHODS

In this study, we obtained TAMs from PDAC patients and isolated exosomes from their culture medium. We characterized these exosomes and analyzed their miRNA expression profiles using Multiplex miRNA assays with FirePlex particle technology. Additionally, we conducted in vitro co-culture experiments between PDAC cells and conditioned media or exosomes from TAMs to investigate the crosstalk between these cells via exosomes. Furthermore, we evaluated the in vivo lung metastasis of PDAC cells treated with TAM-derived exosomes in athymic nude mice.

RESULTS

TAMs from PDAC patients promoted the invasiveness and migratory potential of PDAC cells, partially through the effects of TAM-derived exosomes. Specifically, we identified two microRNAs, miR-202-5p and miR-142-5p, which were transferred from TAM-derived exosomes to PDAC cells, resulting in the suppression of phosphatase and tensin homolog deleted on chromosome ten (PTEN) and promoting their invasiveness and migratory potential. We also found that distal metastasis was increased in PDAC cells treated with TAM-derived exosomes, partially through miR-202-5p and miR-142-5p.

CONCLUSIONS

Exosomal transfer of miR-202-5p and miR-142-5p plays a significant role in conferring invasiveness and migratory potential to PDAC cells. Targeting exosome communication may represent a promising new therapeutic strategy for reducing cancer metastasis of PDACs.

miR-2765 involved in ammonia nitrogen stress via negative regulation of autophagy in shrimp

MicroRNA (miRNA) is a highly conserved non-coding tiny endogenous RNA molecule that regulates various cellular functions by inhibiting mRNA translation or promoting the degradation of proteins. In this study, we identified a specific miRNA (designed as Pva-miR-2765) from Penaeus vannamei, which widely distributed in different tissues of shrimp, with the highest concentration found in the intestine. Through fluorescence in situ hybridization (FISH), we observed that Pva-miR-2765 is primarily located in the cytoplasm. Interestingly, we found that the expression of Pva-miR-2765 significantly decreased in hemocytes, hepatopancreas and gill under ammonia nitrogen stress. Furthermore, when Pva-miR-2765 was silenced, the autophagy level in shrimp significantly increased. Additionally, Pva-miR-2765 was found to promote pathological damage in the hepatopancreas of shrimp. Subsequently, correlation analysis revealed a negative relationship between the expression of Pva-miR-2765 and PvTBC1D7. To confirm this interaction, we conducted a dual luciferase reporter gene assay, which demonstrated that Pva-miR-2765 inhibit the expression of PvTBC1D7 by interacting with its 3'UTR. And the expression level of PvTBC1D7 in shrimp decreased significantly under ammonia nitrogen stress in Pva-miR-2765 overexpressed. Our findings suggest that Pva-miR-2765 can reduce autophagy in P. vannamei by inhibiting the regulation of PvTBC1D7, thereby participating in the oxidative stress of shrimp caused by ammonia nitrogen stress.

Protein lysine acetylation played an important role in NH3-induced AEC2 damage and pulmonary fibrosis in piglets

Gaseous ammonia (NH3), as a main air pollutant in pig farms and surrounding areas, directly affects animal and human health. The lung, as an important organ for gas exchange in the respiratory system, is damaged after NH3 exposure, but the underlying mechanism needs to be further explored. In this study, seven weeks old piglets were exposed to 50 ppm NH3 for 30 days, and displayed pulmonary fibrosis. Then, the toxicological mechanism of NH3-induced pulmonary fibrosis was explored from the aspects of whole genome wide protein expression and post-translational modification. Totally, 404 differentially expressed proteins (DEPs) and 136 differentially lysine acetylated proteins (DAPs) were identified. The expression or lysine acetylation levels of proteins involved in mitochondrial energy metabolism including fatty acid oxidation (CPT1A, ACADVL, ACADS, HADHA, and HADHB), TCA cycle (IDH2 and MDH2), and oxidative phosphorylation (NDUFB7, NDUFV1, ATP5PB, ATP5F1A, COX5A, and COX5B) were significantly changed after NH3 exposure, which suggested that NH3 disrupted mitochondrial energy metabolism in the lung of piglets. Next, we found that type 2 alveolar epithelial cells (AEC2) damaged after NH3 exposure in vivo and in vitro. Integrin-linked kinase (ILK) was enriched in focal adhesion pathway, and showed significantly up-regulated acetylation levels at K191 (FC = 2.99) and K209 sites (FC = 1.52) after NH3 exposure. We illustrated that ILK-K191 hyper-acetylation inhibited AEC2 proliferation and induced AEC2 apoptosis by down-regulating pAKT-S473 in vitro. In conclusion, for the first time, our study revealed that protein acetylation played an important role in the process of NH3-induced pulmonary fibrosis in piglets. Our findings provided valuable insights into toxicological harm of NH3 to human health.

Integrative bioinformatics analysis of biomarkers and pathways for exploring the mechanisms and molecular targets associated with pyroptosis in type 2 diabetes mellitus

Introduction

Research has shown that pyroptosis contributes greatly to the progression of diabetes and its complications. However, the exact relationship between this particular cell death process and the pathology of type 2 diabetes mellitus (T2DM) remains unclear. In this study, we used bioinformatic tools to identify the pyroptosis-related genes (PRGs) associated with T2DM and to analyze their roles in the disease pathology.

Methods

Two microarray datasets, GSE7014 and GSE25724, were obtained from the GEO database and assessed for differentially expressed genes (DEGs). The T2DM-associated DEGs that overlapped with differentially expressed PRGs were noted as T2DM-PRGs. Subsequently, 25 T2DM-PRGs were validated and subjected to functional enrichment analysis through Gene Ontology annotation analysis, Kyoto Encyclopedia of Genes and Genomes pathway analysis, and gene set enrichment analysis (GSEA). The diagnostic and predictive value of the T2DM-PRGs was evaluated using receiver operating characteristic curves (ROC). Additionally, a single-sample GSEA algorithm was applied to study immune infiltration in T2DM and assess immune infiltration levels.

Results

We identified 25 T2DM-PRGs that were significantly enriched in the nuclear factor-kappa B signaling and prostate cancer pathways. The top five differentially expressed prognostic T2DM-PRGs targeted by miRNAs were PTEN, BRD4, HSP90AB1, VIM, and PKN2. The top five differentially expressed T2DM-PRGs associated with transcription factors were HSP90AB1, VIM, PLCG1, SCAF11, and PTEN. The genes PLCG1, PTEN, TP63, CHI3L1, SDHB, DPP8, BCL2, SERPINB1, ACE2, DRD2, DDX58, and BTK showed excellent diagnostic performance. The immune infiltration analysis revealed notable differences in immune cells between T2DM and normal tissues in both datasets. These findings suggest that T2DM-PRGs play a crucial role in the development and progression of T2DM and could be used as potential diagnostic biomarkers and therapeutic targets.

Discussion

Investigating the mechanisms and biomarkers associated with pyroptosis may offer valuable insights into the pathophysiology of T2DM and lead to novel therapeutic approaches to treat the disease.

Selenium Mitigates Ammonia-Induced Neurotoxicity by Suppressing Apoptosis, Immune Imbalance, and Gut Microbiota-Driven Metabolic Disturbance in Fattening Pigs

Ammonia could be regarded as one detrimental pollutant with an acrid smell in livestock sheds. So far, the pig breeding industry became the main source of atmospheric ammonia. Previous literature demonstrated that excessive ammonia inhalation might cause a series of physiological damage to multiple organs. Unfortunately, the toxicity mechanisms of gaseous ammonia to the porcine nervous system need further research to elucidate. Selenium (Se) involves in many essential physiological processes and has a mitigative effect on the exogenous toxicant. There were scant references that corroborated whether organic Se could intervene in the underlying toxicity of ammonia to the hypothalamus. In the present study, multi-omics tools, ethology, and molecular biological techniques were performed to clarify the detailed mechanisms of relaxation effects of L-selenomethionine on ammonia poisoning. Our results showed that ammonia inhalation caused the clinical symptoms and the increment of positive apoptosis rate in the hypothalamus with the dysfunction of mitochondrial dynamics factors, while obvious mitochondria structure defects were observed. In parallel, the inflammation medium levels and gut microbes-driven metabolism function were altered to mediate the neurotoxicity in fattening pigs through the initiation of inflammation development. Interestingly, L-selenomethionine could attenuate ammonia toxicity by activating the PI3K/Akt/PPAR-γ pathway to inhibit the mitochondria-mediated apoptosis process, blocking the abnormal immune response and the accumulation of reactive oxygen species in the nucleus. Meanwhile, Se could enhance the production performance of fattening sows. Taken together, our study verified the novel hypothesis for the toxicity identification of aerial ammonia and provided a therapeutic strategy for the treatment of occupational poisoning.

Chlorpyrifos induced autophagy and mitophagy in common carp livers through AMPK pathway activated by energy metabolism disorder

Water pollution caused by widely used agricultural pesticide chlorpyrifos (CPF) has aroused extensive public concern. While previous studies have reported on toxic effect of CPF on aquatic animal, little is known about its effect on common carp (Cyprinus carpio L.) livers. In this experiment, we exposed common carp to CPF (11.6 μg/L) for 15, 30, and 45 days to establish a poisoning model. Histological observation, biochemical assay, quantitative real-time polymerase chain reaction (qRT-PCR), Western blot, and integrated biomarker response (IBR) were applied to assess the hepatotoxicity of CPF in common carp. Our results displayed that CPF exposure damaged histostructural integrity and induced liver injury in common carp. Furthermore, we found that CPF-induced liver injury may be associated with mitochondrial dysfunction and autophagy, as evidenced by swollen mitochondria, broken mitochondrial ridges, and increased the number of autophagosomes. Moreover, CPF exposure decreased the activities of ATPase (Na⁺/K⁺-ATPase, Ca²⁺-ATPase, Mg²⁺-ATPase, and Ca²⁺Mg²⁺-ATPase), altered glucose metabolism-related genes (GCK, PCK2, PHKB, GYS2, PGM1, and DLAT), and activated energy-sensing AMPK, indicating that CPF caused energy metabolism disorder. The activation of AMPK further induced mitophagy via AMPK/Drp1 pathway, and induced autophagy via AMPK/mTOR pathway. Additionally, we found that CPF induced oxidative stress (abnormal levels of SOD, GSH, MDA, and H₂O₂) in common carp livers, which further contributed to the induction of mitophagy and autophagy. Subsequently, we confirmed a time-dependent hepatotoxicity caused by CPF in common carp via IBR assessment. Our findings presented a new insight into molecular mechanism of CPF induced-hepatotoxicity in common carp, and provided a theoretical basis for evaluating CPF toxicity to aquatic organisms.

Selenium Alleviates Ammonia-Induced Splenic Cell Apoptosis and Inflammation by Regulating the Interleukin Family/Death Receptor Axis and Nrf2 Signaling Pathway

Ammonia (NH₃) is a harmful gas in livestock houses. So far, many researchers have demonstrated that NH₃ is detrimental to animal and human organs. Selenium (Se) is one of the essential trace elements in the body and has a good antioxidant effect. However, there was little conclusive evidence that Se alleviated NH₃ poisoning. To investigate the toxic mechanism of NH₃ on pig spleen and the antagonistic effect of L-selenomethionine, a porcine NH₃-poisoning model and an L-selenomethionine intervention model were established in this study. Our results showed that NH₃ exposure increased the apoptosis rate, while L-selenomethionine supplementation alleviated the process of excessive apoptosis. Immunofluorescence staining, real-time quantitative polymerase chain reaction (qRT-PCR), and western blot results confirmed that exposure to NH₃ changed the expression levels of interleukin family factors, apoptosis, death receptor, and oxidative stress factors. Our study further confirmed that excessive NH₃ induced inflammatory response and mediated necroptosis leading to cell apoptosis by activating the Nrf2 signaling pathway. Excessive NH₃ could mediate spleen injury through oxidative stress-induced mitochondrial dynamics disorder. L-Selenomethionine could alleviate inflammation and abnormal apoptosis by inhibiting the IL-17/TNF-α/FADD axis. Our study would pave the way for comparative medicine and environmental toxicology.

Ammonia-induced oxidative stress triggered proinflammatory response and apoptosis in pig lungs

Ammonia, a common toxic gas, is not only one of the main causes of haze, but also can enter respiratory tract and directly affect the health of humans and animals. Pig was used as an animal model for exploring the molecular mechanism and dose effect of ammonia toxicity to lung. In this study, the apoptosis of type II alveolar epithelial cells was observed in high ammonia exposure group using transmission electron microscopy. Gene and protein expression analysis using transcriptome sequencing and western blot showed that low ammonia exposure induced T-cell-involved proinflammatory response, but high ammonia exposure repressed the expression of DNA repair-related genes and affected ion transport. Moreover, high ammonia exposure significantly increased 8-hydroxy-2-deoxyguanosine (8-OHdG) level, meaning DNA oxidative damage occurred. In addition, both low and high ammonia exposure caused oxidative stress in pig lungs. Integrated analysis of transcriptome and metabolome revealed that the up-regulation of LDHB and ND2 took part in high ammonia exposure-affected pyruvate metabolism and oxidative phosphorylation progress, respectively. Inclusion, oxidative stress mediated ammonia-induced proinflammatory response and apoptosis of porcine lungs. These findings may provide new insights for understanding the ammonia toxicity to workers in livestock farms and chemical fertilizer plants.

Nutrient sensing signaling and metabolic responses in shrimp Litopenaeus vannamei under acute ammonia stress

Ammonia is the primary environmental factor affecting the growth and health of crustaceans. It would induce oxidative stress and metabolic disorders. Extra amount of energy was demanded to maintain the physiological functions under ammonia stress. However, limited information was available on its effects on the main nutrient metabolism, as well as the nutrient sensing signaling pathways. In the present study, shrimp Litopenaeus vannamei were exposed to acute ammonia stress and injected with amino acid solution. The results showed that acute ammonia exposure resulted in lower free amino acid levels in hemolymph, incomplete activation of the mechanistic target of rapamycin (mTOR) signaling and cascaded less protein synthesis in muscle. It induced autophagy and activated the AMP-activated protein kinase (AMPK) pathway. Meanwhile, ammonia exposure enhanced glycolysis and lipogenesis, but inhibited lipolysis. The results characterized the integrated metabolic responses and nutrient signaling to ammonia stress. It provides critical clues to understand the growth performance and physiological responses in shrimp under ammonia stress.

MicroRNA-202-5p-dependent inhibition of Bcl-2 contributes to macrophage apoptosis and atherosclerotic plaque formation

BACKGROUND

The identification of microRNA (miRNA)-related molecular mechanisms has advanced the development of new therapeutics for atherosclerosis (AS). The roles of miR-202-5p- in the pathogenic mechanisms of AS have not been explored.

METHODS

Macrophages were transfected with a series of miR-202-5p mimic/inhibitor, and then assessed for changes in viability, apoptosis, and secretion of inflammatory cytokines. The regulatory mechanism of miR-202-5p was explored through dual-luciferase reporter gene assay. A mouse model of AS was developed in ApoE^-/- mice fed with high-fat diet to examine the in vivo effects of miR-202-5p on atherosclerotic plaque formation, collagen synthesis, and fiber cap thickness.

RESULTS

Elevated miR-202-5p was found in atherosclerotic plaque tissues of the mice. miR-202-5p was able to induce macrophage apoptosis and release of pro-inflammatory factors. Besides, miR-202-5p limited Bcl-2 expression and elevated the levels of Bax, cleaved caspase-3, and cleaved caspase-9. Bcl-2 was concluded as a target gene of miR-202-5p. The pro-apoptotic effect of miR-202-5p on macrophages was achieved via limiting Bcl-2. In the mouse AS model, restoration of miR-202-5p stimulated atherosclerotic plaque formation, but reduced collagen synthesis and fiber cap thickness.

CONCLUSION

These data collectively suggest a pro-apoptotic action of miR-202-5p in macrophages that contributes to atherosclerotic plaque formation.

Oxidative stress mediated immunosuppression caused by ammonia gas via antioxidant/oxidant imbalance in broilers

1. Ammonia is one of major air pollutants in intensive poultry houses, where it causes immunosuppression in broilers. Although previous studies have focused on a particular organ, data on multiple organs have not been reported.2. In the following work, broilers were exposed to environmental ammonia (0, 10, 20, and 40 mg/m³ from 1-21 d old; and 0, 15, 30, and 60 mg/m³ from 22-42 d old).3. Ammonia exposure reduced bird spleen index at 42 d and thymus index at 14, 28, 35 and 42 d, meaning that ammonia caused immunosuppression in birds. Moreover, high ammonia exposure down-regulated the expression of toll-like receptor 4 (TLR4) in lung tissue at 21 d, as well as TLR4 in lung and tracheal mucosa at 42 d when analysed using qRT-PCR. It increased SIgA in saliva at 42 d when analysed by ELISA. Ammonia increased interleukin-6 (IL-6), IL-1β, interferon-α (IFN-α), and IFN-γ in serum at 28 d from the ELISA assay, which indicated that all of these factors took part in ammonia-immunosuppression in birds.4. Three antioxidants (CAT, SOD, T-AOC) decreased, and one oxidant MDA increased after ammonia exposure in the liver and blood, which indicated that ammonia caused oxidative stress via the imbalance of antioxidants/oxidants in birds.5. Correlation analysis showed that TLR4 and TLR15 in the tracheal mucosa were significantly positively related to IFN-γ and negatively related to IL-6. TLR2 in the lung was significantly positively related to IL-1β, and TLR2 in bird tracheal mucosa was negatively related to IL-6 in serum.6. The results suggested that oxidative stress mediated immunosuppression caused by ammonia gas via antioxidant/oxidant imbalance in broilers.

Organic Selenium Alleviates Ammonia-Mediated Abnormal Autophagy by Regulating Inflammatory Pathways and the Keap1/Nrf2 Axis in the Hypothalamus of Finishing Pigs

Ammonia is a significant pollutant in the livestock houses and the atmospheric environment, and excessive ammonia would harm the health of livestock and breeders. Previous studies have shown that ammonia exposure could damage the tissue structure of the nervous system, but the molecular mechanism of ammonia-induced hypothalamus damage was still unclear. The purpose of this study was to determine the role of excessive ammonia in abnormal autophagy of pig hypothalamus and whether selenomethionine would have a mitigating effect on ammonia toxicity. Twenty-four 18-week pigs were randomly divided into four groups: the control group (C group), the selenium group (Se group), the ammonia + selenium group (A + Se group), and the ammonia group (A group). In our study, the expression levels of NF-κB, IL-1β, iNOS, TNF-α, IKK-α, p-IKK-α, Nrf2, ATG5, ATG 10, ATG 12, LC3 I/II, HSP60, HSP70, and HSP90 were increased after ammonia exposure; meanwhile, IFN-γ, IKB-α, p-IKB-α, Keap1, P62, mTOR, AKT, p-AKT, PI3K, SQSTM, and Beclin1 showed decreasing trends. The results indicated that excessive ammonia inhalation inhibited the AKT/mTOR pathway to acclerated autophagy through oxidative stress-mediated inflammation in the porcine hypothalamus. L-selenomethionine could alleviate hypothalamus injury induced by ammonia exposure.

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.

The use of selenomethionine to reduce ammonia toxicity in porcine spleen by inhibiting endoplasmic reticulum stress and autophagy mediated by oxidative stress

Ammonia (NH3) is a typical pollutant in the atmosphere and is well known for its harmful effects on plants, animals as well as human health. Previous studies have shown that NH3 exposure can cause damage to immune organs and impaired immune function in animals. Selenomethionine is a kind of organic selenium, which can not only promote the growth and development of the body, but also inhibit the generation of intracellular reactive oxygen species (ROS), and effectively improve the immune function of the body. Therefore, this study evaluated the toxic effect of NH3 exposure on spleen from a new perspective and investigated the protective effect of selenomethionine on ammonia-induced immunotoxicity. Twenty-four Large White*Duroc*Min pigs were randomly assigned to 4 groups: control group, NH3 group, selenium group, and NH3 + selenium group. Our results showed that NH3 inhalation caused autophagy in the pig spleen, a decrease in lymphocytes, and an increase in autophagic vesicles. Also, NH3 exposure led to a decrease in the activity of some antioxidant enzymes (decreased by about 50%) and a significant increase in the expression of genes related to oxidative stress and endoplasmic reticulum stress (ERS). Our results indicated that selenomethionine mitigated ammonia toxicity in pigs (alleviated about 20-55%). In summary, our findings should be of value in providing a theoretical basis for revealing the toxicity of the high-risk gas NH3, and providing a new perspective on the mechanism of Se against toxic substances.

Oxidative stress links the tumour suppressor p53 with cell apoptosis induced by cigarette smoke

This study was to investigate the effects of oxidative stress in cigarette smoke (CS)-induced cell apoptosis in mice with emphysema. Thirty-two mice were divided into four groups: the control group, the CS group, the CS + Pifithrin-α group, and the CS + NAC group. Pathological changes and apoptosis in lung tissue of mice were detected. The activity of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and total antioxidant capacity (T-AOC) were measured using spectrophotometer. The proteins expression of p53, Bcl-2, Bax, and caspase-3 were determined by western blot. The results showed that cell apoptosis, lung structural damage, and the activity of MDA, as well as the expression of apoptosis-related proteins Bax, total caspase-3, and cleaved caspase-3 were increased in CS-treated mice. The activity of SOD, CAT, and T-AOC, as well as the expression of anti-apoptosis protein Bcl-2 were decreased in CS-treated mice when compared with the control group. However, Pifithrin-α (p53 inhibitor) and N-Acetylcysteine (NAC) could reduce cell apoptosis, lung structural damage and oxidative stress, accelerate the expression of Bcl-2, while suppressing the expression of Bax, total caspase-3 and cleaved caspase-3. More importantly, the treatment with NAC even inhibited the expression of p53. In conclusions, oxidative stress linking the p53 is involved in cell apoptosis in CS-treated emphysema mice.

Circulating microRNAs as putative mediators in the association between short-term exposure to ambient air pollution and cardiovascular biomarkers

BACKGROUND

Exposure to ambient air pollution is associated with increased cardiovascular morbidity and mortality. Circulating microRNAs (miRNAs) may mediate cardiovascular effects of exposure to air pollution. This study aims to investigate whether circulating miRNAs mediate the associations between short-term human exposure to ambient air pollution and cardiovascular biomarkers.

METHODS

Twenty-four healthy adults residing in the Research Triangle area of North Carolina, USA were enrolled between December 2016 and July 2019. Circulating miRNAs, protein, and lipid biomarkers were assessed repeatedly for 3 sessions separated by at least 7 days. Linear mixed-effects models were used to assess the associations between air pollutant concentrations obtained from nearby air quality monitoring stations and miRNAs controlling for covariates including omega-3 index, relative humidity, and temperature. miRNAs that were significantly altered were then matched with protein or blood lipid biomarkers using either Ingenuity Pathway Analysis or a literature search. A mediation analysis was performed to test the statistical significance of miRNA's mediating effects between exposure to air pollution and cardiovascular biomarkers.

RESULTS

Short-term exposure to ambient fine particulate matter (PM_2.5), ozone (O₃), and nitrogen dioxide (NO₂) was associated with changes in 11, 9, and 24 circulating miRNAs, respectively. Pathway analysis showed that several miRNAs including miR-125b-5p, miR-144-5p, miR-26a-5p, and miR-34a-5p may mediate the effects of air pollutant exposure on the changes of downstream protein / lipid biomarkers including serum amyloid A (SAA), C-reactive protein (CRP), soluble vascular adhesive molecules 1 (sICAM1), total cholesterol, and high-density lipoproteins (HDL). Mediation analysis showed that only miR-26a-5p significantly mediated air pollutant (PM_2.5 and NO₂)-induced effects on blood CRP and total cholesterol levels. For example, 34.1% of PM_2.5-associated changes in CRP were significantly mediated by miR-26a-5p at lag4 [indirect effects, 0.06 (0.02, 0.10), P = 0.005]. Similarly, the proportions of indirect effects of miR-26a-5p on the association between NO₂ exposure and CRP were 46.8% at lag2 [0.06 (0.02, 0.11), P = 0.003], 61.2% at lag3 [0.05 (0.00, 0.09), P = 0.04], and 30.8% at 5-day moving average [0.06 (0.02, 0.10), P = 0.01]. In addition, omega-3 index may be a significant modifying factor of the mediated effects of miRNAs.

CONCLUSIONS

This study demonstrates that short-term exposure to ambient PM_2.5, O₃, and NO₂ was associated with specific circulating miRNAs, and some of which may mediate their effects on the downstream inflammation and blood lipid markers.

Liver transcriptome analysis reveals biological pathways and transcription factors in response to high ammonia exposure

Aim: Ammonia is a toxic gas that not only causes environmental pollution, but also is harmful to human health after inhalation. Liver is an important detoxification organ that can convert external or metabolized toxic substances into nontoxic substances. However, the toxic effects of ammonia exposure on livers have not been well studied.Method: In this study, pigs were used as an animal model and were exposed to 80 ppm ammonia (8 h during 12 days), and then, RNA-seq were conducted to explore the key genes in response to high ammonia exposure in livers.Result: Gene set enrichment analysis (GSEA) showed that the genes associated with hypoxia, inflammatory response, and apoptosis were up-regulated in the ammonia group, but the genes associated with DNA replication, linoleic acid metabolism, and glycolysis were down-regulated. Totally, 556 differentially expressed genes (DEGs) including 54 genes that encode the transcription factors (TFs) were identified between the exposure and control groups. GO and KEGG pathway analysis suggested that these DEGs were involved in inflammatory response, oxidative stress, apoptosis, immune, and cell cycle. Furthermore, the TF-target interaction analysis showed that FOS, HIF-1α, JUNB, ATF3, REL, and KLF4 were important TFs in regulating the hepatic gene expression in response to high ammonia exposure.Conclusion: Altogether, our findings not only presented a comprehensive mRNA transcriptome profile of liver after high ammonia exposure, but also found some key genes and TFs that could be used to investigate the toxicity mechanism of high ammonia on livers.

Ammonia induces autophagy via circ-IFNLR1/miR-2188-5p/RNF182 axis in tracheas of chickens

Ammonia (NH₃ ), an air pollutant in the living environment, has many toxic effects on various tissues and organs. However, the underlying mechanisms of NH₃ -induced tracheal cell autophagy remains poorly understood. In present study, chickens and LMH cells were used as NH₃ exposure models to investigate toxic effects. The change of tracheal tissues ultrastructure showed that NH₃ exposure induced autolysosomes. The differential expression of 12 circularRNAs (circRNAs) was induced by NH₃ exposure using circRNAs transcriptome analysis in broiler tracheas. We further found that circ-IFNLR1 was down-regulated, and miR-2188-5p was up-regulated in tracheal tissues under NH₃ exposure. Bioinformatics analysis and dual luciferase reporter system showed that circ-IFNLR1 bound directly to miR-2188-5p and regulated each other, and miR-2188-5p regulated RNF182. Overexpression of miR-2188-5p caused autophagy and its inhibition partially reversed autophagy in LMH cells which were caused by ammonia stimulation or knockdown of circ-IFNLR1. The expressions of three autophagy-related genes (LC3, Beclin 1, and BNIP3) were observably up-regulated. Our results indicated that NH₃ exposure caused autophagy through circ-IFNLR1/miR-2188-5p/RNF182. These results provided new insights for the study of ammonia on environmental toxicology on ceRNA and circRNAs in vivo and vitro.

Development, optimization, and validation of a method for detection of cartap, thiocyclam, thiosultap-monosodium, and thiosultap-disodium residues in plant foods by GC-ECD

A method was developed for the simultaneous determination of four nereistoxin-related pesticides, viz. cartap, thiocyclam, thiosultap-monosodium, and thiosultap-disodium, in 20 plant foods. The samples were extracted using a hydrochloric acid solution containing cysteine hydrochloride, derivatized to nereistoxin under alkaline conditions, and analyzed by gas chromatography with electron capture detector. The average recoveries of the method were 72-108%, with relative standard deviations (RSDs) of 0.3-14.7% (n = 1200, p < 0.05). The intermediate precision and reproducibility experiments using established methods were also carried out. All the results passed the Cochrane and Grubbs tests (n = 2400, p < 0.05). The RSDs of intermediate precision and RSDs of reproducibility among laboratories were in the ranges 1.7-10.9% and 2.4-15.3% (n = 2400, p < 0.05), respectively, indicating that the accuracy and precision of the method are satisfactory. This method can be used to detect nereistoxin-related pesticides in plant foods.

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.

Pva-miR-252 participates in ammonia nitrogen-induced oxidative stress by modulating autophagy in Penaeus vannamei

MicroRNAs (miRNAs) are critical post-transcriptional regulators, which play a crucial role in resistance to adverse environmental stress by regulating autophagy. However, the mechanism of miRNA involved in the autophagy regulation of shrimp under ammonia nitrogen stress is still limited. In the present study, ammonia nitrogen could induce hepatopancreas injury and oxidative stress of P. vannamei, and significantly increase the content of ROS in hemocytes by flow cytometry. Simultaneously, it is accompanied by autophagy occurred in the hemocytes and hepatopancreas. Furthermore, the qRT-PCR analysis revealed that the expression of pva-miR-252 in P. vannamei decreased significantly after ammonia nitrogen stress, and pva-miR-252 negatively regulated PvPI3K by binding to 3'UTR of PvPI3K by double-luciferase assay. Pva-miR-252 overexpression could significantly increase the level of autophagy, and restore the autophagy inhibition caused by Chloroquine in vitro , whereas silencing of pva-miR-252 resulted in the opposite effect. More importantly, overexpression of pva-miR-252 could enhance the activity of antioxidant enzymes and reduced the production of ROS of shrimp under ammonia nitrogen stress. In conclusion, pva-miR-252 could positively regulate autophagy through PvPI3K and improve the antioxidant enzyme activity of P. vannamei under ammonia nitrogen stress, and our study provides a novel theoretical molecular mechanism for further understanding the shrimp cope with a high ammonia nitrogen environment.

Environmental Stress in Chickens and the Potential Effectiveness of Dietary Vitamin Supplementation

Environmental stressors can promote the vulnerability of animals to infections; it is therefore, essential to understand how stressors affect the immune system, the adaptive capacity of animals to respond, and effective techniques in managing stress. This review highlights scientific evidence regarding environmental stress challenge models and the potential effectiveness of vitamin supplementation. The major environmental stressors discussed are heat and cold stress, feed restriction, stocking density, and pollutants. Much work has been done to identify the effects of environmental stress in broilers and layers, while few involved other types of poultry. Studies indicated that chickens' performance, health, and welfare are compromised when challenged with environmental stress. These stressors result in physiological alterations, behavioral changes, decreased egg and meat quality, tissue and intestinal damage, and high mortalities. The application of vitamins with other nutritional approaches can help in combating these environmental stressors in chickens. Poultry birds do not synthesize sufficient vitamins during stressful periods. It is therefore suggested that chicken diets are supplemented with vitamins when subjected to environmental stress. Combination of vitamins are considered more efficient than the use of individual vitamins in alleviating environmental stress in chickens.

Ficus hirta Vahl. promotes antioxidant enzyme activity under ammonia stress by inhibiting miR-2765 expression in Penaeus vannamei

Ficus hirta Vahl. has been reported to have hepatoprotective, antitumor, antibacterial functions, and is used to treat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Ammonia nitrogen is one of the most common environmental stress factors in aquaculture. Long-term exposure to high concentrations of ammonia nitrogen can induce oxidative stress and increase the risk of infections. However, whether Ficus hirta Vahl. has effect on ammonia nitrogen stress is unclear. In present study we report that Ficus hirta Vahl. improves the activity of total antioxidant capacity (T-AOC), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) of shrimp and decreases shrimp mortality caused by ammonia nitrogen stress. It is demonstrated that miR-2765 is negatively regulate the antioxidant capacity. We find that SOD was a direct target gene of miR-2765. MiR-2765 can bind to 3'-untranslated region (3'-UTR) of SOD to inhibit its transcription. Furthermore, Ficus hirta Vahl. down-regulates miR-2765 to activate the antioxidant capacity to alleviate the damage caused by ammonia nitrogen stress. Interestingly, overexpression of miR-2765 could attenuate the protective effect of Ficus hirta Vahl. on shrimp under ammonia nitrogen stress. These data indicate that Ficus hirta Vahl. alleviates the damage of ammonia nitrogen stress in shrimp by repressing miR-2765 and activating the antioxidant enzyme system. This study will provide a theoretical basis and a new perspective for assessing the toxicity mechanism of ammonia nitrogen in the process of farming on shrimp.

The contributions of miR-25-3p, oxidative stress, and heat shock protein in a complex mechanism of autophagy caused by pollutant cadmium in common carp (Cyprinus carpio L.) hepatopancreas

Cadmium (Cd) is a toxic heavy metal that can be discharged into water environment through industrial activities, threatening the health of aquatic organisms and humans. MicroRNA (miRNA) plays an important role in the process of autophagy. The purpose of this experiment was to study the mechanism of Cd-induced autophagy in common carp hepatopancreas. We established a Cd poisoning model of common carp and explored ultrastructure, two oxidation indicators, three antioxidant indicators, miR-25-3p, two heat shock proteins (Hsps), and nine autophagy-related genes. The results confirmed that deleterious effect of Cd caused the injury of hepatopancreas and the appearance of hepatopancreas autophagic cells in common carp. At the same time, Cd exposure increased the contents of hydrogen peroxide (H₂O₂) and malonaldehyde (MDA), and decreased the activities of catalase (CAT), superoxide dismutase (SOD), and total antioxidative capacity (T-AOC), meaning that Cd caused oxidative stress via the imbalance between peroxide level and antioxidant capacity. Moreover, exposure to Cd increased mRNA expression of microtubule associated protein-1 light chain 3 beta (LC3-II), Dynein, Beclin 1, autophagy-related gene 5 (Atg5), and autophagy-related gene 12 (Atg12); and decreased mRNA expression of mechanistic target of rapamycin kinase (mTOR), indicating that excess Cd caused autophagy, and AMPK/mTOR/ULK1 signaling pathway took part in autophagy induced by Cd in common carp hepatopancreas. Furthermore, Cd down-regulated miR-25-3p and up-regulated its three target genes (AMPK, ULK1 as well as PTEN), suggesting that miR-25-3p mediated autophagy induced by Cd. In addition, we found that Hsps were activated via the up-regulation of Hsp70 and Hsp90. Moreover, oxidative stress mediated autophagy via Hsps in Cd-treated common carp hepatopancreas and Cd-induced autophagy was time dependent. In summary, miR-25-3p, oxidative stress, and Hsps participated in autophagy caused by Cd in common carp hepatopancreas. This study provided a new idea for the mechanism of Cd-induced autophagy in hepatopancreas.

IKKε knockout alleviates angiotensin II-induced apoptosis and excessive autophagy in vascular smooth muscle cells by regulating the ERK1/2 pathway

Inhibitor of nuclear factor-κB kinase subunit ε (IKKε) is an important signal regulator in the formation of abdominal aortic aneurysm (AAA). However, the underlying mechanism remains to be elucidated. Therefore, the present study aimed to investigate the mechanism underlying IKKε function in AAA formation by studying apoptosis and autophagy in angiotensin II (Ang II)-induced vascular smooth muscle cells (VSMCs). AngII was used to stimulate VSMCs for 24 h to simulate the process of AAA formation. VSMCs were transfected with IKKε small interfering RNA to investigate the effect of IKKε on AAA formation, cell apoptosis and autophagy. IKKε deficiency led to reduced mitochondrial damage and apoptosis in VSMCs in the early stage of apoptosis in vitro, as demonstrated using a JC-1 probe. IKKε deficiency also reduced autophagy and decreased the formation of autophagic vacuoles in VSMCs, demonstrated using transmission electron microscopy. The decrease in apoptosis caused by IKKε knockdown was reversed when the autophagic flow was blocked using bafilomycin A1. Western blot analysis further revealed that IKKε deficiency negatively regulated the ERK1/2 signaling pathway to reduce autophagy. Collectively, the results of the present study revealed that IKKε played a key role in apoptosis by inducing excessive autophagy, thereby potentially contributing to AAA formation. These findings further revealed the mechanism underlying IKKε function in the formation of AAA.

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.

Immunosuppression, oxidative stress, and apoptosis in pig kidney caused by ammonia: Application of transcriptome analysis in risk assessment of ammonia exposure

Ammonia (NH₃) is a recognized environmental contaminant around the world and has adverse effects on animal and human health. However, the mechanism of the renal toxicity of NH₃ is not well understood. Pigs are considered an ideal model for biomedical and toxicological research because of the similarity to humans in physiological and biochemical basis. Therefore, in this study, twelve pigs were selected as research objects and randomly divided into two groups, namely the control group and the NH₃ group. The formal experiment lasted 30 days. The effects of excessive NH₃ inhalation on the kidney of fattening pig were evaluated by chemical analysis, ELISA, transcriptome analysis and real-time quantitative PCR (qRT-PCR) from the renal antioxidant level, renal function, blood ammonia content and gene level. Our results showed that excessive NH₃ exposure could cause an increase in blood NH₃ content, a reduction in renal GSH-Px, SOD and GSH, as well as an increase in MDA levels and an increase in serum creatinine, urea and uric acid levels. In addition, transcriptome analysis showed that NH₃ exposure caused changes in 335 differentially expressed genes (DEGs) (including 126 up-regulated DEGs and 109 down-regulated DEGs). Some highly expressed DEGs were enriched into GO terms associated with immune function, oxidative stress, and apoptosis and were verified by qRT-PCR. The qRT-PCR results were comsistent with the transcriptome results. Our results indicated that NH₃ exposure could cause changes in renal transcriptional profiles and kidney function, and induce kidney damage in the fattening pigs through oxidative stress, immune dysfunction and apoptosis. Our present study provides novel insights into the immunotoxicity mechanism of NH₃ on kidney.

Cadmium induces the thymus apoptosis of pigs through ROS-dependent PTEN/PI3K/AKT signaling pathway

Cadmium (Cd) is a transition metal that is toxic to living organisms in the environment and endangers living organisms. To explore whether Cd induces apoptosis in pig thymus and its possible mechanism, the role Cd induction of the PTEN/PI3K/Akt pathway in apoptosis of thymus cells was studied in pigs. We found that Cd exposure (the feed is treated with Cd) significantly increased Cd accumulation in the thymus of pigs. The TUNEL assay confirmed the typical apoptotic characteristics of thymus in Cd group. Moreover, in the Cd group, the activities of antioxidant indices decreased significantly, while the levels of oxidative stress indexes increased significantly, and the mRNA levels of GSH, CAT, Gpx1, GST, SOD1, and SOD2 decreased obviously. Moreover, the mRNA and protein levels of PTEN/PI3K/AKT and apoptosis-related genes were detected by qPCR and western blotting. The results show that the expressions of PI3K and AKT decreased, while the expression of PTEN increased, indicating that pathway activated. With the PTEN/PI3K/AKT pathway regulating, Bcl-2 expression decreased. Conversely, the mRNA and protein expression of apoptosis-related genes were up-regulated. In conclusion, accumulation of Cd in the pigs caused oxidative damage to immune tissues. In addition, Cd-induced oxidative stress activates the PTEN/PI3K/AKT pathway, inducing apoptosis in the thymus of pigs.

Quantitative proteomic analysis of trachea in fatting pig exposed to ammonia

Ammonia (NH₃) is considered as the main pollutant in livestock houses and air environment, and its adverse effects on animal and human health have attracted widespread attention. However, trachea proteomics respond to NH₃ is lacking, which is crucial to understanding how NH₃ induces respiratory damage. In this study, we performed labeled quantitative proteomic (TMT-MS) analysis in the trachea of fatting pigs exposed to NH₃ for 30 days. The proteomic results were then validated by Immunohistochemistry (IHC) and Parallel Reaction Monitoring (PRM). The results showed that a total of 126 differentially abundant proteins (DAPs) were identified (fold change <0.83 or > 1.2 and P < 0.05), including 70 differentially up-regulated proteins (DUPs) and 56 differentially down-regulated proteins (DDPs). These proteins were mainly located in intracellular regions and involved in immune response, metabolism and protein synthesis. The results of DAPs (EHHADH, RPL28, SLC25A6, TUBB6, CD14, CTSS, RPS11, RPL19, SLC25A5, RPS8, FABP3, RPL21, RPL34, RPL32, PDIA3, FBP1, HSPH1, SAR1A and SEC24C) verified by IHC and PRM were consistent with the proteomic results. The results of this study provided a basis and a novel insight for understanding the mechanism of NH₃-induced tracheal injury. SIGNIFICANCE: Ammonia (NH₃) is considered as the main pollutant in livestock houses and air environment, and its adverse effects on animal and human health have attracted widespread attention. However, trachea proteomics respond to NH₃ is lacking, which is crucial to understanding how NH₃ induces respiratory damage. Therefore, in this study, labeled quantitative proteomics (TMT-MS) was used to detect trachea tissue samples from finishing pigs in NH₃ exposure group and control group, and PRM method was used to further verify the highly abundant proteins in NH₃ exposure samples, so as to identify new diagnostic markers for NH₃ poisoning. The results of this study provided a basis and a novel insight for understanding the molecular pathological mechanism of NH₃-induced tracheal injury.

Excessive ammonia inhalation causes liver damage and dysfunction by altering gene networks associated with oxidative stress and immune function

Ammonia (NH₃) is a major gaseous pollutant in livestock production and has adverse effects on production, health and welfare of animals. The liver is one of the target organs of NH₃, and excessive NH₃ inhalation can induce liver damage. However, the toxicity assessment of NH₃ on pig liver and its mechanism have not been reported yet. Recently, transcriptome analysis has become a major method to study the toxic mechanism of pollutants in environmental toxicology. Therefore, in the present study, we examined the effects of excessive NH₃ inhalation on the liver of fattening pig through chemical analysis, ELISA, transcriptome analysis and real-time quantitative PCR (qRT-PCR). Our results showed that the transcriptome analysis database of fattening pig liver under excessive NH₃ exposure, and 449 differentially expressed genes (DEGs) (including 181 up-regulated DEGs and 168 down-regulated DEGs) were found. Some genes associated with the 3 Gene Ontology (GO) terms (liver function, immune, antioxidant defense) were validated by quantitative real-time PCR. In addition, the activities of GPT and GOT in NH₃ group were significantly increased by 63.5% and 37.4% (P < 0.05), respectively. Our results indicated that NH₃ exposure could cause changes in transcriptional profiles and liver function, and induce liver damage in fattening pigs through oxidative stress and immune dysfunction. Our study results not only provide a new perspective for the toxicity assessment of NH₃, but also enrich the toxicological mechanism of NH₃.

Energy metabolism disorder mediated ammonia gas-induced autophagy via AMPK/mTOR/ULK1-Beclin1 pathway in chicken livers

Ammonia gas is a well-known environmental pollution gas, threatening human health. Ammonia gas is also one of the most harmful gases to livestock and poultry for many years. Many studies have demonstrated toxic effect of ammonia gas on animal health, such as eyes, respiratory system, and digestive system. However, the effect of ammonia gas toxicity on chicken livers and underlying molecular mechanism remains unclear. In this study, we selected chicken liver as research object and duplicated successfully ammonia gas poisoning model of chickens. 1-day-old Ross-308 broilers were randomly divided into the control group (the low ammonia gas group), and two treatment groups (the middle ammonia gas group and the high ammonia gas group) (3 replicates per group and 12 chickens per replicate). Ammonia gas concentration in the low ammonia gas group was ≤5 mg/m³ during day 1-42. Ammonia gas concentration in the middle group was set as 10 ± 0.5 mg/m³ during day 1-21, and 15 ± 0.5 mg/m³ during day 22-42). Ammonia gas concentration in the high ammonia gas group was set as 20 ± 0.5 mg/m³ during day 1-21, and 45 ± 0.5 mg/m³ during day 22-42. The ultrastructure of chicken livers was observed. The activities of four ATPases (Na⁺K⁺-ATPase, Mg⁺⁺-ATPase, Ca⁺⁺-ATPase, and Ca⁺⁺Mg⁺⁺-ATPase), the expression of twelve energy metabolism-related genes (HK1, HK2, PK, PFK, PDHX, CS, LDHA, LDHB, SDHA, SDHB, avUCP, and AMPK), as well as the expression of ten autophagy-related genes (PI3K, LC3I, LC3II, Beclin1, SQSTM1, mTOR, ULK1, ATG5, ATG12, and ATG13) were measured to explore the effect of ammonia gas on energy metabolism and autophagy in chicken livers. Our results showed that excess ammonia gas induced mitochondrial and autophagic damage in chicken liver tissue cells. Meanwhile, ATPases activities were inhibited and the expression of energy metabolism-related genes changed during ammonia gas treatment, meaning that excess ammonia gas caused energy metabolism disorder. Furthermore, ammonia gas exposure altered the expression of autophagy-related genes, suggesting that ammonia gas treatment caused autophagy in chicken livers. Moreover, ammonia gas-induced AMPK compensatory up-regulation activated autophagy process through inhibiting mTOR and promoting ULK1. In addition. there were dose-dependent and time-dependent effects on all detected indexes in ammonia gas-caused chicken liver cell damage. Taken together, AMPK/mTOR/ULK1-Beclin1 pathway participated in energy metabolism disorder-mediated autophagic injury caused by ammonia gas exposure in chicken livers.

Exposure to High Aerial Ammonia Causes Hindgut Dysbiotic Microbiota and Alterations of Microbiota-Derived Metabolites in Growing Pigs

Ammonia, an atmospheric pollutant in the air, jeopardizes immune function, and perturbs metabolism, especially lipid metabolism, in human and animals. The roles of intestinal microbiota and its metabolites in maintaining or regulating immune function and metabolism are irreplaceable. Therefore, this study aimed to investigate how aerial ammonia exposure influences hindgut microbiota and its metabolites in a pig model. Twelve growing pigs were treated with or without aerial ammonia (35 mg/m³) for 25 days, and then microbial diversity and microbiota-derived metabolites were measured. The results demonstrated a decreasing trend in leptin (p = 0.0898) and reduced high-density lipoprotein cholesterol (HDL-C, p = 0.0006) in serum after ammonia exposure. Besides, an upward trend in hyocholic acid (HCA), lithocholic acid (LCA), hyodeoxycholic acid (HDCA) (p < 0.1); a downward trend in tauro-deoxycholic acid (TDCA, p < 0.1); and a reduced tauro-HDCA (THDCA, p < 0.05) level were found in the serum bile acid (BA) profiles after ammonia exposure. Ammonia exposure notably raised microbial alpha-diversity with higher Sobs, Shannon, or ACE index in the cecum or colon and the Chao index in the cecum (p < 0.05) and clearly exhibited a distinct microbial cluster in hindgut indicated by principal coordinate analysis (p < 0.01), indicating that ammonia exposure induced alterations of microbial community structure and composition in the hindgut. Further analysis displayed that ammonia exposure increased the number of potentially harmful bacteria, such as Negativibacillus, Alloprevotella, or Lachnospira, and decreased the number of beneficial bacteria, such as Akkermansia or Clostridium_sensu_stricto_1, in the hindgut (FDR < 0.05). Analysis of microbiota-derived metabolites in the hindgut showed that ammonia exposure increased acetate and decreased isobutyrate or isovalerate in the cecum or colon, respectively (p < 0.05). Unlike the alteration of serum BA profiles, cecal BA data showed that high ammonia exposure had a downward trend in cholic acid (CA), HCA, and LCA (p < 0.1); a downward trend in deoxycholic acid (DCA) and HDCA (p < 0.05); and an upward trend in glycol-chenodeoxycholic acid (GCDCA, p < 0.05). Mantel test and correlation analysis revealed associations between microbiota-derived metabolites and ammonia exposure-responsive cecal bacteria. Collectively, the findings illustrated that high ammonia exposure induced the dysbiotic microbiota in the hindgut, thereby affecting the production of microbiota-derived short-chain fatty acids and BAs, which play a pivotal role in the modulation of host systematic metabolism.

Decreased expression of IDH1 by chronic unpredictable stress suppresses proliferation and accelerates senescence of granulosa cells through ROS activated MAPK signaling pathways

Studies suggested that psychosocial stress was associated with female fertility decline, but the underlying mechanisms remained unclear. Granulosa cells (GCs) are important somatic cells to support follicular development and oocyte maturation. Herein, by using a mouse model of chronic unpredictable stress (CUS), we found that CUS induced oxidative stress damage in mouse ovaries, also inhibited GCs proliferation and accelerated GCs senescence. Isocitrate dehydrogenase-1 (IDH1), an antioxidant related gene by generating NADPH, was shown to be downregulated in GCs of CUS mice. Consistently, IDH1 knockdown inhibited cell proliferation and accelerated cellular senescence in KGN cells in vitro. In addition, IDH1 knockdown increased ROS content, induced autophagy activation and triggered cell cycle arrest in S and G2/M phases in KGN cells, which could be rescued by N-acetyl-l-cysteine (NAC), a ROS scavenger in these cells. Besides, IDH1 knockdown activated MAPK signaling pathways, including ERK, JNK and p38 signaling pathways in KGN cells, while NAC could suppress the activation. Through using inhibitors of MAPK signaling pathways, we showed that the activation of ERK pathway participated in autophagy related cell proliferation inhibition and cellular senescence, whereas JNK and p38 MAPK signaling pathways took part in regulation cell cycle arrest associated cell proliferation inhibitory and senescence in IDH1 knockdown KGN cells. Our findings suggested that downregulated expression of IDH1 induced by CUS has a physiological function in GCs proliferation and senescence through ROS activated MAPK signaling pathways, and improvement of IDH1 activity might be a beneficial therapeutic strategy for ovarian dysfunction.

Tetrandrine Ameliorates Myocardial Ischemia Reperfusion Injury through miR-202-5p/TRPV2

Objective

This study is aimed at investigating the therapeutic effects of tetrandrine (Tet) on myocardial ischemia reperfusion (I/R) injury and probe into underlying molecular mechanism.

Methods

H9C2 cells were divided into hypoxia/oxygenation (H/R) group, H/R+Tet group, H/R+Tet+negative control (NC) group, and H/R+Tet+miR-202-5p inhibitor group. RT-qPCR was utilized to monitor miR-202-5p and TRPV2 expression, and TRPV2 protein expression was detected via western blot and immunohistochemistry in H9C2 cells. Cardiomyocyte apoptosis was evaluated through detection of apoptosis-related markers and flow cytometry. Furthermore, myocardial enzyme levels were detected by ELISA. Rats were randomly separated into sham operation group, I/R group, I/R+Tet group (50 mg/kg), I/R+Tet+NC group, and I/R+Tet+miR-202-5p inhibitor group. miR-202-5p and TRPV2 mRNA expression was assessed by RT-qPCR. TRPV2 protein expression was detected through western blot and immunohistochemistry in myocardial tissues. Apoptotic levels were assessed via apoptosis-related proteins and TUNEL. Pathological changes were observed by H&E staining. Myocardial infarction size was examined by Evans blue-TCC staining.

Results

Abnormally expressed miR-202-5p as well as TRPV2 was found in H/R H9C2 cells and myocardial tissues of I/R rats, which was ameliorated following Tet treatment. Tet treatment significantly suppressed H/R- or I/R-induced cardiomyocyte apoptosis. ELISA results showed that CK-MB and LDH levels were lowered by Tet treatment in H/R H9C2 cells and serum of I/R rats. H&E staining indicated that Tet reduced myocardial injury in I/R rats. Also, myocardial infarction size was lowered by Tet treatment. The treatment effects of Tet were altered following cotreatment with miR-202-5p inhibitor.

Conclusion

Our findings revealed that Tet may ameliorate myocardial I/R damage via targeting the miR-202-5p/TRPV2 axis.

Ammonia exposure causes the disruption of the solute carrier family gene network in pigs

Ammonia is the main harmful gas in livestock houses. However, the toxic mechanism of ammonia is still unclear. Therefore, we examined the effects of ammonia exposure on different tissues of fattening pigs by histological analysis and transcriptome techniques in this study. The results showed that there were varying degrees of pathological changes in liver, kidney, hypothalamus, jejunum, lungs, spleen, heart and trachea of fattening pigs under ammonia exposure. Notably, the extent of damage in liver, kidney, jejunum, lungs, hypothalamus and trachea was more severe than that in heart and spleen. Transcriptome results showed that ammonia exposure caused changes in 349, 335, 340, 229, 120, 578, 407 and 115 differentially expressed genes in liver, kidney, spleen, lung, trachea, hypothalamus, jejunum and heart, respectively. Interestingly, the changes in solute vector (SLC) family genes were found in all 8 tissues, and the verified gene results (SLC11A1, SLC17A7, SLC17A6, SLC6A4, SLC22A7, SLC25A3, SLC28A3, SLC7A2, SLC6A6, SLC38A5, SLC22A12, SLC34A1, SLC26A1, SLC26A6, SLC27A5, SLC22A8 and SLC44A4) were consistent with qRT-PCR results. In conclusion, ammonia exposure can cause pathological changes in many tissues and organs of fattening pigs and changes in the SCL family gene network. Importantly, the SCL family is involved in the toxic mechanism of ammonia. Our findings will provide a new insight for better assessing the mechanism of ammonia toxicity.

A potential mechanism associated with lead-induced spermatogonia and Leydig cell toxicity and mitigative effect of selenium in chicken

Lead (Pb) is a toxic heavy metal pollutants and can damage male reproductive function. Selenium (Se) possesses an ability of antagonizing Pb toxicity. However, biological events in the process of Pb toxicity and mitigative effect of Se are not well understood. The aim of present research was to investigate potential mechanism of Se against Pb toxicity from the perspective of oxidative stress, heat shock response and autophagy in the spermatogonia and Leydig cell of chicken. The cells from one-day-old male Hyline chickens were treated with Se (0.5 μmol/L) and/or Pb (20 μmol/L) for 24 h, respectively. Cell viability, cell ultrastucture, Pb and Se concentrations, testosterone level, oxidative stress indicators and relative expression of heat shock proteins (HSPs) and autophagy-related genes were measured. The results showed that spermatogonia was more tolerant to Pb than Leydig cell; cell injury was confirmed via histological assessment, cell viability and testosterone level; oxidative stress was further indicated by the decrease of catalase, glutathione peroxidase, glutathione-s-transferase and superoxide dismutase activities and the increase of malondialdehyde and reactive oxygen species contents. Pb increased expression of HSPs (27, 40, 60, 70 and 90). Meanwhile Pb induced autophagy through up-regulation of autophagy-related proteins 5, Beclin 1, Dynein, light chain 3 (LC3)-I and LC3-II and down-regulation of mammalian target of rapamycin in two type cells of chicken. However, Se intervention mitigated the aforementioned alterations caused by Pb. In conclusion, Pb led to oxidative stress, which triggered heat shock response and autophagy; Se administration mitigated reproductive toxicity of Pb through strengthening antioxidant defense in the spermatogonia and Leydig cell of chicken.

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.

New insights into the interplay between miRNAs and autophagy in the aging of intervertebral discs

Intervertebral disc degeneration (IDD) has been widely known as a main contributor to low back pain which has a negative socioeconomic impact worldwide. However, the underlying mechanism remains unclear. MicroRNAs (miRNAs) are a class of small noncoding RNAs that post-transcriptionally regulate gene expression and serve key roles in the ageing process of intervertebral disc. Autophagy is an evolutionarily conserved process that maintains cellular homeostasis through recycling of nutrients and degradation of damaged or aged cytoplasmic organelles. Autophagy has been proposed as a "double-edged sword" and autophagy dysfunction of IVD cells is considered as a crucial reason of IDD. A rapidly growing number of recent studies demonstrate that both miRNAs and autophagy play important roles in the progression of IDD. Furthermore, accumulated research has indicated that miRNAs target autophagy-related genes and influence the onset and development of IDD. Hence, this review focuses mainly on the current findings regarding the correlations between miRNA, autophagy, and IDD and provides new insights into the role of miRNA-autophagy pathway involved in IDD pathophysiology.

MicroRNAs as Biomarkers for Animal Health and Welfare in Livestock

MicroRNAs (miRNAs) are small and highly conserved non-coding RNA molecules that orchestrate a wide range of biological processes through the post-transcriptional regulation of gene expression. An intriguing aspect in identifying these molecules as biomarkers is derived from their role in cell-to-cell communication, their active secretion from cells into the extracellular environment, their high stability in body fluids, and their ease of collection. All these features confer on miRNAs the potential to become a non-invasive tool to score animal welfare. There is growing interest in the importance of miRNAs as biomarkers for assessing the welfare of livestock during metabolic, environmental, and management stress, particularly in ruminants, pigs, and poultry. This review provides an overview of the current knowledge regarding the potential use of tissue and/or circulating miRNAs as biomarkers for the assessment of the health and welfare status in these livestock species.

The effect of ammonia exposure on energy metabolism and mitochondrial dynamic proteins in chicken thymus: Through oxidative stress, apoptosis, and autophagy

Ammonia (NH₃) gas is an atmospheric pollutant, produced from different sources. In poultry houses NH₃ is produced from the biological process of liter, manure, and protein composition. It has been well documented that NH₃ adversely effects the health of chickens. However, the underlying mechanism of NH₃ toxicity on chicken thymus is still unknown. Thymus is an important immune organ, which play a critical role in eliciting protective immune responses to ensure healing process and elimination of harmful stimuli. The results showed that NH₃ exposure reduced antioxidant activities and induced oxidative stress in thymus tissues. Histological observation showed normal morphology of chicken thymus in control group. In contrast, increased number of nuclear debris, vacuoles, and cristae break were seen in NH₃ affected chickens. Ultrastructural analysis indicated mitochondrial breakdown, disappearance, vacuoles, and chromatin condensation in NH₃ treated groups. The mRNA and protein expression of apoptosis related genes were significantly enhanced in the chicken thymus of NH₃ affected chickens compared to control group. Moreover, Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay results suggested that NH₃ exposure increased positive stained nuclei in the chicken thymus. Meanwhile, NH₃ exposure reduced the number of CD8⁺ T-lymphocytes, decreased the adenosine triphosphate (ATPase) activities. The mRNA and protein expression of autophagy, energy metabolism, and mitochondrial dynamics proteins were altered by NH₃ exposure. In summary, these results showed that NH₃ induced oxidative stress, apoptosis and autophagic cell death (ACD), which could be the possible causes of immune damage and structural impairment in chicken thymus.