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.

Molecular mechanism of selenium against lead-induced apoptosis in chicken brainstem relating to heat shock protein, selenoproteins, and inflammatory cytokines

Extensive application of lead (Pb) brought about environmental pollution and toxic reactions of organisms. Selenium (Se) has the effect of antagonizing Pb poisoning in humans and animals. However, it is still unclear how Pb causes brainstem toxicity. In the present study, we wanted to investigate whether Se can alleviate Pb toxicity in chicken brainstems by reducing apoptosis. One hundred and eighty chickens were randomly divided into four groups, namely the control group, the Se group, the Pb group, and the Se/Pb group. Morphological examination, ultrastructural observation, relative mRNA expressions of genes on heat shock proteins (HSPs); selenoproteins; inflammatory cytokines; and apoptosis-related factors were investigated. The results showed that Pb exposure led to tissue damage and apoptosis in chicken brainstems. Furthermore, an atypical expression of HSPs (HSP27, HSP40, HSP60, HSP70, and HSP90); selenoprotein family glutathione peroxidase (GPx) 1, GPx2, GPx3, and GPx4), thioredoxin reductases (Txnrd) (Txnrd1, Txnrd2, and Txnrd3), dio selenoprotein famliy (diodothyronine deiodinases (Dio)1, Dio2, and Dio3), as well as other selenoproteins (selenoprotein (Sel)T, SelK, SelS, SelH, SelM, SelU, SelI, SelO, Selpb, selenoprotein n1 (Sepn1), Sepp1, Sepx1, Sepw1, 15-kDa selenoprotein (Sep15), and selenophosphate synthetases 2 (SPS2)); inflammatory cytokines (Interleukin 2 (IL-2), IL-4, IL-6, IL-12β, IL-17, and Interferon-γ (IFN-γ)); and apoptosis-related genes (B-cell lymphoma-2 (Bcl-2), tumor protein 53 (p53), Bcl-2 Associated X (Bax), Cytochrome c (Cyt c), and Caspase-3) were identified. An inflammatory reaction and apoptosis were induced in chicken brainstems after exposure to Pb. Se alleviated the abnormal expression of HSPs, selenoproteins, inflammatory cytokines, and apoptosis in brainstem tissues of chickens treated with Pb. The results indicated that HSPs, selenoproteins, inflammatory, and apoptosis were involved in Se-resisted Pb poisoning. Overall, Se had resistance effect against Pb poisoning, and can be act as an antidote for Pb poisoning in animals.

Physiological characteristics, rhizosphere soil properties, and root-related microbial communities of Trifolium repens L. in response to Pb toxicity

Trifolium repens L. (T. repens) is considered a potential phytoremediation species due to its large biomass and ability to accumulate and tolerate heavy metals. Lead (Pb) is an important heavy metal pollutant that can affect plant growth, photosynthesis, and enzyme activity. However, response mechanism of microorganisms in three root niches of metal tolerant plants to Pb is not completely understood. Therefore, in this study, a Pb poisoning model of T. repens was established with a Pb gradient (0, 1000 mg/kg, 2000 mg/kg, and 3000 mg/kg), and was used to evaluate growth and physiological responses, as well as enrichment and transport coefficients in T. repens, and explore the characteristics of rhizosphere soil and microbial composition of three root niches. We found that Pb stress caused oxidative injury, and inhibited photosynthesis in T. repens. 16S rDNA sequencing analysis showed that the richness of microbial communities in bulk soil was higher than that in rhizosphere soil both under Pb stress and Pb nonstress conditions. Moreover, Proteobacteria was dominant phylum in bulk and rhizosphere soils, and Proteobacteria and Cyanobacteria were dominant phylum in endophytic bacteria. For the first time, we systematically investigated the response of Pb from bulk soil to plant leaves. The results showed that microbial interaction existed between bulk and rhizosphere soil. Rhizosphere bacterium Haliangium was positively correlated with urease activity and soil nutrients. Endophytic bacterium Pseudomonas was positively correlated with plant biomass and played an important role in Pb tolerance of T. repens. In addition, endophytic bacteria formed complex correlation networks with growth and physiological indexes of both root and shoot, moreover the network in root was more complicated. Taken together, Pb stress dose-dependently inhibited the growth of plants. This study provided a theoretical basis for the further development of microbial cooperation with plant remediation of heavy metal contaminated soil.

HSP27-HSP40-HSP70-HSP90 pathway participated in molecular mechanism of selenium alleviating lead-caused oxidative damage and proteotoxicity in chicken Bursa of Fabricius

Lead (Pb), a toxic environmental pollutant, is hazardous to the health of humans and birds. Bursa of Fabricius (BF) is a unique organ of birds. Toxic substances can attack BF and induce proteotoxicity. Increased heat shock proteins (HSPs) can induce oxidative damage. Selenium (Se) can alleviate harmful substance-caused oxidative damage. This study aimed to investigate whether Pb can cause oxidative damage and proteotoxicity, as well as Se reverse Pb-caused chicken BF toxicity. A model of chickens treated with Se and Pb alone and in combination was established. BFs were collected on days 30, 60, and 90. H&E and qRT-PCR were performed to observe the microstructure and to detect HSP27, HSP40, HSP60, HSP70, and HSP90 mRNA levels, respectively, in BFs. Multivariate correlation analysis and principal component analysis were conducted to explore the correlation among the five HSPs. In our results, Pb caused BF damage and up-regulated the five HSPs at three time points, causing oxidative damage and proteotoxicity via HSP27-HSP40-HSP70-HSP90 pathway. Furthermore, Pb caused time-dependent stress on HSP27, HSP40, HSP60, and HSP70. In addition, Se relieved Pb-caused damage and up-regulation of HSPs. Taken together, we concluded that Se alleviated Pb-caused oxidative injury and proteotoxicity in chicken BFs via the HSP27-HSP40-HSP70-HSP90 pathway.

The protective effect of Luteolin on chicken spleen lymphocytes from ammonia poisoning through mitochondria and balancing energy metabolism disorders

Ammonia poses a significant challenge in the contemporary intensive breeding industry, resulting in substantial economic losses. Despite this, there is a dearth of research investigating efficacious strategies to prevent ammonia poisoning in poultry. Consequently, the objective of this study was to investigate the molecular mechanisms through which Luteolin (Lut) safeguards mitochondria and restores equilibrium to energy metabolism disorders, thereby shielding chicken spleen lymphocytes from the detrimental effects of ammonia poisoning. Chicken spleen lymphocytes were categorized into 3 distinct groups: the control group, the ammonia group (with the addition of 1 mmol/L of ammonium chloride), and the Lut group (with the treatment of 0.5 μg/mL of Lut for 12 h followed by the addition of 1 mmol/L of ammonium chloride). These groups were then cultured for a duration of 24 h. To investigate the potential protective effect of Lut on lymphocytes exposed to ammonia, various techniques were employed, including CCK-8 analysis, ultrastructural observation, reagent kit methodology, fluorescence microscopy, and quantitative real-time PCR (qRT-PCR). The findings indicate that Lut has the potential to mitigate the morphological damage of mitochondria caused by ammonia poisoning. Additionally, it can counteract the decline in mitochondrial membrane potential, ATP content, and ATPase activities (specifically Na+/K+-ATPase, Ca2+-ATPase, Mg2+-ATPase, and Ca/Mg2+-ATPase) following exposure to ammonia in lymphocytes. Lut also has the ability to regulate the expression of genes involved in mitochondrial fusion (Opa1, Mfn1, and Mfn2) and division (Drp1 and Mff) in spleen lymphocytes after ammonia exposure. This regulation leads to a balanced energy metabolism (HK1, HK2, LDHA, LDHB, PFK, PK, SDHB, and ACO2) and provides protection against ammonia poisoning.

Cadmium exposure caused cardiotoxicity in common carps (Cyprinus carpio L.): miR-9-5p, oxidative stress, energetic impairment, mitochondrial division/fusion imbalance, inflammation, and autophagy

Cadmium (Cd), a toxic heavy metal pollutant, is a threat to human and eatable fish health. Common carps are widely cultivated and eaten by humans. However, there are no reports about Cd-damaged common carp hearts. Our experiment attempted to investigate the cardiotoxicity of Cd to common carps by establishing a common carp Cd exposure model. Our results showed that Cd injured hearts. Moreover, Cd treatment induced autophagy via miR-9-5p/Sirt1/mTOR/ULK1 pathway. Cd exposure caused oxidant/antioxidant imbalance and oxidative stress; and led to energetic impairment. Energetic impairment partook in oxidative stress-mediated autophagy through AMPK/mTOR/ULK1 pathway. Furthermore, Cd caused mitochondrial division/fusion imbalance and resulted in inflammatory injury via NF-κB-COX-2-PTGEs and NF-κB-COX-2-TNF-α pathways. Oxidative stress mediated mitochondrial division/fusion imbalance, further induced inflammation and autophagy via OPA1/NF-κB-COX-2-TNF-α-Beclin1 and OPA1/NF-κB-COX-2-TNF-α/P62 pathways under Cd treatment. Taken together, miR-9-5p, oxidative stress, energetic impairment, mitochondrial division/fusion imbalance, inflammation, and autophagy participated in the mechanism of Cd-cardiotoxicity to common carps. Our study revealed harmful effect of Cd on hearts, and provided new information for researches of environmental pollutant toxicity.

Cadmium induced time-dependent kidney injury in common carp via mitochondrial pathway: Impaired mitochondrial energy metabolism and mitochondrion-dependent apoptosis

Toxic effect of heavy metal cadmium (Cd) on fish kidneys had been reported. Mitochondrion is an important organelle for maintaining kidney function, while its role in Cd-induced kidney injury in common carp remained unclarified. In this experiment, we established a poisoning model of common carp with Cd exposure (0.26 mg/L) for 15, 30, and 45 days. Serum biochemistry determination, histological observation, TUNEL assay, qRT-PCR, Western blot, and integrated biomarker response (IBR) were applied to assess the nephrotoxicity of Cd to common carp. Our results displayed that Cd exposure increased the levels of serum biochemical indexes (UREA, CRE, and UA), indicating kidney injury. We further revealed via histological observation that Cd damaged structural integrity of kidneys, as evidenced by renal glomerulus and renal tubular injury, hallmark phenotypes of apoptosis, and mitochondrial damage, suggesting that mitochondria damage and apoptosis were involved in Cd-induced kidney injury. Moreover, Cd exposure decreased ATPase (Na⁺/K⁺-ATPase, Ca²⁺-ATPase, Mg²⁺-ATPase, and Ca²⁺Mg²⁺-ATPase) activities as well as PGC-1a and Mfn2 levels, while increased Drp1 and PINK1 levels as well as LC3-II/LC3-I ratio, which indicated that Cd-impaired renal energy metabolism was related to mitochondrial dysfunction. Additionally, we found that Cd induced oxidative stress (abnormal levels of SOD, CAT, GPX, MDA, and H₂O₂) in kidneys, which was involved in triggering mitochondrial dysfunction and further impairing mitochondrial energy metabolism. Moreover, the occurrence of mitochondria-dependent apoptosis was found after Cd-exposure in common carp kidneys, as indicated by enhanced levels of Bax, CytC, APAF1, Caspase-9, and Caspase-3, while declined level of Bcl-2. Subsequently, we confirmed a time-dependent nephrotoxicity of Cd to common carp via IBR assessment. In conclusion, Cd induced time-dependent nephrotoxicity in common carp via mitochondrial pathway. This mitochondria-oriented study shed light on underlying mechanisms of Cd-induced renal pathologies and provided a theoretical basis for evaluating Cd toxicity to aquatic organisms.

Transcriptome analysis revealed the mechanism of Luciobarbus capito (L. capito) adapting high salinity: Antioxidant capacity, heat shock proteins, immunity

Salinity has a significant influence on the physiology of freshwater aquatic organisms. However, there are few studies on the hematology and immunology of freshwater fish under high salinity. In the current study, we aimed to analyze the adaptive effect of salt stress on L. capito spleen immune function and hematology using transcriptomic analysis. We replicated a L. capito acute salinity stress model, and collected blood and spleens from freshwater and saltwater fish. It was found that salinity affected significantly the numbers of leukocytes, lymphocytes, neutrophils, and red blood cells, as well as the content of haemoglobin. Salt treatment resulted in a significant increase in the expression of HSP70, HSP90, CAT, SOD, and GPX1 genes in L. capito spleens. Transcriptomic analysis revealed a total of 546 differentially expressed genes (DEGs) in spleens, including 224 up-regulated DEGs and 322 down-regulated DEGs. In addition, GO enrichment analysis revealed immune system process, multicellular organismal process, and biological regulation of genes with the most differences in biological processes. KEGG enrichment analysis showed that the regulation of lipolysis in adipocyte, FoxO signaling pathway, Hematopoietic cell lineage signaling pathway, and HIF-1 signaling pathway were significantly enriched. L. capito adapted oxidative to high salinity through FoxO signaling pathway and immune to high salinity through Hematopoietic cell lineage signaling pathway. At the same time, we selected 10 DEGs for qRT-PCR detection, and the results showed that the qRT-PCR results were consistent with our RNA-Seq results, indicating that transcriptome sequencing was accurate and reliable. In conclusion, our results demonstrated that the improvement of antioxidant capacity, heat shock protein and immunity are involved in the molecular mechanism of L. capito adapting to high salinity. Our findings provided a rationale for further study on high salinity adaptation and related enrichment pathways.

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.

The effect of acute toxicity from tributyltin on Liza haematocheila liver: Energy metabolic disturbance, oxidative stress, and apoptosis

Tributyltin (TBT), a highly toxic and persistent organic pollutant, is widely distributed in coastal waters. Liza haematocheila (L. haematocheila) is one of bony fish distributing coincident with TBT, and exposure risk of TBT to this fish is unknown. In this study, L. haematocheila was exposed to TBT of 0, 3.4, 6.8, and 17.2 μg/L for 48 h to explore hepatic response mechanism. Our results showed that Sn content in livers increased after 48 h of exposure. HSI and histological changes indicated that TBT suppressed liver development of L. haematocheila. TBT reduced ATPase activities. The increased RB in blood and the reduced TBC were measured after exposure to TBT. T-AOC and antioxidant enzymes SOD, CAT, and GPx activities were inhibited while MDA content was increased. Liver cells showed apoptosis characteristics after TBT exposure. Furthermore, transcriptome analysis of livers was performed and the results showed energy metabolism-related GO term (such as ATPase complex and ATPase dependent transmembrance transport complex), oxidative stress-related GO term (such as Celllular response to oxidative stress and Antioxidant activity), and apoptosis-related GO term (such as Regulation of cysteine-type endopeptidase activity involved in apoptosic signaling pathway). Moreover, we found six energy metabolism-related differentially expressed genes (DEGs) including three up-regulated DEGs (atnb233, cftr, and prkag2) and three down-regulated DEGs (acss1, abcd2, and smarcb1); five oxidative stress-related DEGs including one up-regulated DEG (mmp9) and four down-regulated DEG (prdx5, hsp90, hsp98, and gstf9); as well as six apoptosis-related DEGs including five up-regulated DEGs (casp8, cyc, apaf1, hccs, and dapk3) and one down-regulated DEG (bcl2l1). Our transcriptome data above further confirmed that acute stress of TBT led energy metabolic disturbance, oxidative stress, and apoptosis in L. haematocheila livers.

Nano-selenium protects grass carp hepatocytes against 4-tert-butylphenol-induced mitochondrial apoptosis and necroptosis via suppressing ROS-PARP1 axis

4-tert-butylphenol (4-tBP) is a monomer widely used in the synthesis of industrial chemicals, and posed a high risk to aquatic animals. Our study focused on toxic phenotype and mechanism of detoxification in grass carp hepatocytes (L8824) after 4-tBP-treatment. In this experiment, L8824 displayed hallmark phenotypes of apoptosis and necroptosis after 4-tBP exposure, as evidenced by changes in cell morphology, increased rates of apoptosis and necrosis, the loss of MMP, the accumulation of ROS, and changes in associated factors (PARP1, JNK, Bid, Bcl-2, Bax, AIFM1, CytC, Caspase 9, APAF1, Caspase 3, TNF-α, TNFR1, RIPK1, RIPK3, and MLKL). Furthermore, we found that 4-tBP-induced apoptosis and necroptosis were reversed by pretreating with N-Acetylcysteine (a ROS scavenger) and 3-Aminobenzamide (a PARP1 inhibitor), indicating that 4-tBP induced the onset of mitochondrial apoptosis and necroptosis in L8824 via activating ROS-PARP1 axis. Nano-selenium (Nano-Se) is a novel form of Se with a noteworthy antioxidant capacity. Here, Nano-Se was found to have preventive, therapeutic, and resistance effects on 4-tBP-induced L8824 apoptosis and necroptosis. Nano-Se co-treatment with 4-tBP was an optimal way to alleviate 4-tBP-induced apoptosis and necroptosis. We demonstrated for the first time that Nano-Se protected L8824 against 4-tBP-induced mitochondrial apoptosis and necroptosis through ROS-PARP1 pathway. This study will provide a new theoretical basis for 4-tBP toxicology researches and aquatic animal protection.

EGCG alleviated Mn exposure-caused carp kidney damage via trpm2-NLRP3-TNF-α-JNK pathway: Oxidative stress, inflammation, and tight junction dysfunction

Manganese (Mn), an essential trace metal element in organisms. However, with extensive use of Mn in industry and agriculture, Mn becomes a heavy metal pollutant in water. (-)-epigallocatechin gallate (EGCG), an tea polyphenols, can alleviate metal toxicity. Kidney is an important detoxifying organ, but toxic mechanism of Mn to kidneys is unclear, which needs further research. Carp is an Asian important economical species for fisheries and a biological model for studying environmental toxicology. Thus, we established excess Mn and EGCG-supplemented carp model to explore molecular mechanism of EGCG alleviating Mn-caused carp kidney damage. In this experiment, we set a control group (the Con group), a Mn treatment group (the Mn group, 90 mg/L Mn), a EGCG supplement group (the EG group, 75 mg/kg EGCG), and a combined group (the Mn + EG group, 90 mg/L Mn and 75 mg/kg EGCG). Transcriptome, qRT-PCR, kit, and morphology method results indicated that excess Mn caused oxidative stress, inflammatory damage, and tight junction dysfunction in carp kidneys. Excess Mn-triggered oxidative stress caused tight junction dysfunction via trpm2-NLRP3-TNF-α-JNK pathway and inflammation. EGCG reversed the harm of Mn to fish through the above mechanism. The findings of this study provided the evidence of EGCG-alleviated Mn poisoning and offered new ideas for reducing heavy metal environmental pollution risk.

Mitochondrion Participated in Effect Mechanism of Manganese Poisoning on Heat Shock Protein and Ultrastructure of Testes in Chickens

Manganese (Mn) poisoning can happen in the case of environmental pollution and occupational exposure. However, the underlying mechanisms of Mn-induced teste toxicity and whether mitochondrion and heat shock proteins (HSPs) are involved in toxic effect of Mn on chicken testes remain poorly understood. To investigate this, MnCl₂·4H₂O was administered in the diet (600, 900, and 1800 mg/kg Mn) of chickens for 30, 60, and 90 days. Electron microscopy and qPCR were performed. Results showed that Mn exposure suppressed dose- and time-dependently HSP40 and HSP60 mRNA levels, meanwhile increased does-dependently HSP27, HSP70, and HSP90 mRNA levels at all three time points under three Mn exposure concentrations. Furthermore, Mn treatment damaged myoid cells, spermatocytes, and Sertoli cells through electron microscopic observation, indicating that Mn treatment damaged chicken testes. In addition, abnormal shapes of mitochondria were found, and mitochondria displayed extensive vacuolation. The increase of HSP90 and HSP70 induced by Mn exposure inhibited HSP40 and stimulated HSP27, respectively, in chicken testes, which needs further to be explored. Taken together, our study suggested that there was toxic effect in excess Mn on chickens, and HSPs and mitochondria were involved in the mechanism of dose-dependent injury caused by Mn in chicken testes. This study provided new insights for Mn toxicity identification in animal husbandry production practice.

Melatonin alleviates lead-induced fatty liver in the common carps (Cyprinus carpio) via gut-liver axis

As a widespread aquatic environmental contaminant, Lead (Pb) can provoke hepatic injury in various animals. Melatonin (MT) plays a crucial role in the regulation of inflammatory response. Accumulating evidence elucidates exogenous toxins can elicit hepatic lipid metabolic disorders by influencing the gut microbiome. Nevertheless, the effects of Pb on gut microbiota and hepatic lipid metabolism of the common carps, and whether MT can prevent and cure Pb-induced toxicity via regulating microbiome remains unknown. Here, metagenomic and transcriptomic analysis were subsequently implemented to identify the Pb exposure-triggered prominent alternation of gut-liver signal. In the present study the severe intestinal injury and fatty liver formation caused by Pb in common carp were preliminarily determined. Metagenomic analysis confirmed that the gut microbiome dominant phyla, family and genus of the common carps were Fusobacteria, Fusobacteriaceae and Cetobacterium. Meanwhile, lipopolysaccharide (LPS) biosynthesis pathway was regarded as one of the main responsible for Pb exposure. Subsequently, LPS was demonstrated as the Pb-triggered microbial-derived signal of the common carps by ELISA analysis, and involves in the hepatic metabolic disorders via deteriorating the intestinal barrier. Additionally, it confirmed that hepatocytes ferroptosis associated with Pb-evoked fatty liver of the common carps, and the aggravation of lysosomal dyshomeostasis as well as inhibition of AMPK phosphorylation were referred to lipid metabolic disorders. The results of the present study demonstrated microbial-derived signal induced by aquatic Pb contaminant cause fatty liver formation in the common carps, and the protective effects of MT on Pb toxicity were performed by receding LPS over-synthesis, restraining microbiota-sourced LPS transport, along with attenuation of hepatocytes ferroptosis.

Effect of Multicomponent Intervention on Functional Decline in Chinese Older Adults: A Multicenter Randomized Clinical Trial

OBJECTIVES

To confirm whether multicomponent exercise following vivifrail recommendations was an effective method for improving physical ability, cognitive function, gait, balance, and muscle strength in Chinese older adults.

METHODS

This was a multicenter and randomized clinical trial conducted in Jiangsu, China, from April 2021 to April 2022. Intervention lasted for 12 weeks and 104 older adults with functional declines were enrolled. All participants were randomly assigned to a control (usual care plus health education) or exercise group (usual care plus health education plus exercise). Primary outcomes were the change score of Short Physical Performance Battery (SPPB) and activities of daily living (ADL). The secondary outcomes included instrumental activities of daily living, Tinetti scores, Frailty score, short-form Mini Nutritional Assessment, Mini-Mental State Examination, Geriatric Depression Scale-15, the 12-item Short Form Survey, 4-meter gait speed test, 6-min walking distance, grip strength, and body composition analysis.

RESULTS

Among the participants, the average age was 85 (82, 88) years. After 12 weeks of follow-up, the exercise group showed a significant improvement in SPPB, with a change of 2 points (95% confidence interval [0, 3.5], P<0.001) compared to control. In contrast, SPPB remained stable in the control group. Compared to the control group, ADL improved in the exercise group, as did instrumental activities of daily living, Tinetti, Frailty, Short Form Survey, 4-meter gait speed test, and 6-min walking distance. Although there was no significant difference between groups in body composition analysis after post-intervention, the exercise group still improved in soft lean mass (P=0.002), fat-free mass (P=0.002), skeletal muscle mass index (P<0.001), fat-free mass index (P=0.004), appendicular skeletal muscle mass (P<0.001), and leg muscle mass (P<0.001), while the control group had no significant increase. No difference was observed in adverse events during trial period.

CONCLUSIONS

The multicomponent exercise intervention following vivifrail recommendations is an effective method for older adults with functional decline and can reverse the functional decline and improve gait, balance, and muscle strength. Additionally, the 12-week multicomponent exercise method provides guidance for Chinese medical professionals working in the field of geriatrics and is a promising method to improve physical function in the general population.

Effect of arsenic stress on the intestinal structural integrity and intestinal flora abundance of Cyprinus carpio

Aquatic organisms such as fish can accumulate high concentrations of arsenic (As), which has toxic effects on fish. However, whether the intestinal flora are involved in As damage to fish intestinal tissues and the underlying process are unclear. Common carp (Cyprinus carpio) were exposed to As (2.83 mg/L) in water for 30 days, and blood, muscle, intestine, and intestine samples were collected. Intestinal pathological sections were observed, and the lipopolysaccharide (LPS) levels in serum and the levels of As accumulation and tight junction-related factors in intestinal tissues were measured. The gut microbiota was analysed by 16S rRNA sequencing. The results showed that As treatment decreased the abundance of microbiota, increased the number of harmful bacteria, and decreased the number of beneficial bacteria in the intestine. In our experiment, the top 30 harmful and beneficial bacteria with the highest relative abundance were identified. Among the top 30 harmful and beneficial bacteria, As treatment resulted in a significant (P < 0.05) increase in harmful bacteria (such as Fusobacteriota, Bacteroidota (LPS-producing bacteria), Verrucomicrobiota, Bacteroides, Aeromonas, and Stenotrophomonas) and a significant (P < 0.05) decrease in beneficial bacteria (such as Actinobacteriota, Planctomycetota, Firmicutes, Reyranella, Akkermansia, and Pseudorhodobacter), which further demonstrated that As affects the abundance of intestinal flora. In addition, As exposure increased the LPS level in serum and the abundance of Bacteroidota (LPS-producing bacteria) in the intestine. Bacteroidota exhibits the six highest relative abundance at the phylum level, which indicates that LPS produced by Bacteroidota can increase the LPS level in serum. Additionally, the protein and gene levels of the tight junction markers ZO-1 and occludin in the intestine were reduced by As treatment, which further indicated that As exposure impaired the structural integrity of the intestine. In conclusion, the results obtained in our study indicate that the intestinal flora, LPS, and tight junctions participate in the impairment of the structural integrity of the common carp intestine resulting from As exposure.

Melatonin alleviates lead-induced intestinal epithelial cell pyroptosis in the common carps (Cyprinus carpio) via miR-17-5p/TXNIP axis

Lead (Pb) has been concerned as one of the most severe hazardous contaminants, because it can cause pyroptosis in multiple tissues of mammals and birds. Melatonin (Mel) has attracted much interest for its role in governing intestinal injury via microRNAs (miRNAs). To explore the effect of Mel on Pb exposure-induced intestinal epithelial cell pyroptosis in common carps by regulating miR-17-5p/TXNIP axis, the Pb exposure and Pb-Mel treated models were constructed in vivo. The results elucidated that the suppressed expression of miR-17-5p and intensified level of TXNIP were primarily detected in Pb-exposed gut tissues, and both abolished with Mel addition, along with downregulated Pb-mediated elevated expression of NLRP3, CASP1, IL1β and GSDMD. Additionally, the targeting relationship between miR-17-5p and TXNIP were demonstrated by dual-luciferase reporter assay, and on this basis, miR-17-5p NC, mimic and inhibitor cell models were established. Thereby, Thereby, the expression of TXNIP in the miR-17-5p mimic groups was significant lower in the Pb-exposure but still elevated than the Control group, and the expression of NLRP3 and NLRP3-dependent pyrotposis-related genes performed consistent alterations. Noticeably, the expression of TXNIP suppressed with Mel addition even in the miR-17-5p inhibitor cell model, resulting in the inactivation of NLRP3 inflammasome-dependent pyroptosis. Overall, we draw the conclusion as Mel attenuates Pb-induced intestinal epithelial cell pyroptosis via miR-17-5p/TXNIP axis. The present study provides a novel perspective for toxicological mechanism of Pb, and new insights for the detoxification mechanism of Mel.

4-tert-butylphenol triggers common carp hepatocytes ferroptosis via oxidative stress, iron overload, SLC7A11/GSH/GPX4 axis, and ATF4/HSPA5/GPX4 axis

4-tert-butylphenol (4-tBP) is a toxic environmental pollutant with moderate bioaccumulation, environmental persistence, and long-term toxicity. Its toxicity to aquatic organisms has become an issue of concern. However, the molecular mechanism of 4-tBP toxicity to aquatic organisms remained unclear. Liver is a target organ for environmental pollutants. Here, we established 4-tBP-exposed toxicity model in vivo and primary hepatocyte model in vitro in common carp (Cyprinus carpio L.). We found increased hepatic-somatic index (HSI) and abnormal serum biochemical indexes (ALT, AST, and LDH) after 4-tBP exposure, indicating liver damage. We further revealed that 4-tBP damaged the structural integrity of the livers with typical features of ferroptosis. Based on toxicogenomics analysis, we found ferroptosis is likely to be involved in the mechanism of 4-tBP-induced liver damage. Moreover, our in vivo and in vitro experiment provided evidences that 4-tBP-exposure led to excess oxidative stress, iron overload, decreased MMP, and abnormal expression of ferroptosis-related factors. Interestingly, ferrostatin-1 (Fer-1, a ferroptosis inhibitor) pretreatment alleviated above changes. In summary, we demonstrated that 4-tBP triggered hepatocytes ferroptosis via oxidative stress, iron overload, SLC7A11/GSH/GPX4 axis, and ATF4/HSPA5/GPX4 axis. For the first time, we discovered that Fer-1 can ameliorate the toxicity of 4-tBP, which needs more investigations. Our results provided a scientific basis of molecular mechanism of 4-tBP-induced fish poisoning.

Immunosuppression participated in complement activation-mediated inflammatory injury caused by 4-octylphenol via TLR7/IκBα/NF-κB pathway in common carp (Cyprinus carpio) gills

4-octylphenol (4-OP), a toxic estrogenic environmental pollutant, can threaten aquatic animal and human health. However, toxic effect of 4-OP on fish has not been reported. To investigate molecular mechanism of gill poisoning caused by 4-OP exposure, a carp 4-OP poisoning model was established, and then blood and gills were collected on day 60. The results demonstrated that gill was a target organ attacked by 4-OP, and exposure to 4-OP caused carp gill inflammatory injury. There were 1605 differentially expressed genes (DEGs, including 898 up-regulated DEGs and 707 down-regulated DEGs). KEGG and GO were used to further analyze obtained 1605 DEGs, indicating that complement activation, immune response, and inflammatory response participated in the mechanism of 4-OP-caused carp gill inflammatory injury. Our data at transcription level further revealed that 4-OP caused complement activation through triggering complement component 3a/complement component 3a receptor (C3a/C3aR) axis and complement component 5a/complement component 5a receptor 1 (C5a/C5aR1) axis, induced immunosuppression through the imbalances of T helper (Th) 1/Th2 cells and regulatory T (Treg)/Th17 cells, as well as caused inflammatory injury via toll like receptor 7/inhibitor kappa B alpha/nuclear factor-kappa B (TLR7/IκBα/NF-κB) pathway. Taken together, immunosuppression participated in complement activation-mediated inflammatory damage in carp gills after 4-OP treatment. The findings of this study will provide pioneering information and theoretical support for the mechanism of 4-OP poisoning, and will provide reference for the assessment of estrogenic environmental pollution risk.

Pharmacological inhibition of eIF2alpha phosphorylation by integrated stress response inhibitor (ISRIB) ameliorates vascular calcification in rats

Vascular calcification (VC) is an independent risk factor for cardiovascular events and all-cause mortality with the absence of current treatment. This study aimed to investigate whether eIF2alpha phosphorylation inhibition could ameliorate VC. VC in rats was induced by administration of vitamin D3 (3×10(5) IU/kg, intramuscularly) plus nicotine (25 mg/kg, intragastrically). ISRIB (0.25 mg/kg·week), an inhibitor of eIF2alpha phosphorylation, ameliorated the elevation of calcium deposition and ALP activity in calcified rat aortas, accompanied by amelioration of increased SBP, PP, and PWV. The decreased protein levels of calponin and SM22alpha, and the increased levels of RUNX2 and BMP2 in calcified aorta were all rescued by ISRIB, while the increased levels of the GRP78, GRP94, and C/EBP homologous proteins in rats with VC were also attenuated. Moreover, ISRIB could prevent the elevation of eIF2alpha phosphorylation and ATF4, and partially inhibit PERK phosphorylation in the calcified aorta. These results suggested that an eIF2alpha phosphorylation inhibitor could ameliorate VC pathogenesis by blocking eIF2alpha/ATF4 signaling, which may provide a new target for VC prevention and treatment.

THE INCREASED PLASMA LEVELS OF INTERMEDIN IN PATIENTS WITH TYPE 2 DIABETES MELLITUS

Context

Intermedin (IMD) is the member of calcitonin gene-related peptide family, and tightly associated with type 2 diabetes mellitus (T2DM). The change of plasma IMD levels in T2DM is still unknown.

Objective

We aimed to investigate the plasma levels of IMD in patients with T2DM.

Design

Fortyone patients with T2DM who were hospitalized in the endocrinology department of Civil Aviation General Hospital from January 2012 to June 2015 were enrolled, and 44 volunteers were selected as the control group.

Subjects and Methods

Plasma level of IMD was detected by ELISA. Diagnostic value of IMD was analyzed by area under the receiver operating characteristic (ROC) curve (AUC).

Results

The plasma level of IMD in T2DM group was higher than that in the healthy control group, whereas smoking or cardiovascular complications did no influence the IMD levels. IMD levels were correlated with BMI, DBP, triglyceride, uric acid, urea nitrogen, fasting and 2 hours postprandial blood glucose, and HbA1C. The greatest value of AUC for IMD was only 58.73%.

Conclusions

Although plasma levels of IMD were increased in patients with T2DM, the very low diagnostic value of IMD for T2DM might not be used for the disease diagnosis.

Complex molecular mechanism of ammonia-induced apoptosis in chicken peripheral blood lymphocytes: miR-27b-3p, heat shock proteins, immunosuppression, death receptor pathway, and mitochondrial pathway

Ammonia gas, a toxic environmental pollutant, is a vital component of PM2.5 aerosols, and can decrease human and animal immunity. Peripheral blood lymphocytes (PBLs) are main immune cells. Nevertheless, poisoning mechanism of PBLs under ammonia exposure remains unclear. Here, we established an ammonia poisoning model of chicken PBLs to explore poisoning mechanism of ammonia-caused apoptosis in chicken PBLs. Cell viability and apoptosis rate were detected using CCK8 assay and flow cytometry, respectively. Mitochondrial membrane potential (MMP) was observed using fluorescent staining. In addition, qRT-PCR was performed to measure mRNA levels of apoptosis-related genes (tumor necrosis factor-α (TNF-α), tumor necrosis factor receptor 1 (TNFR1), TNF receptor-associated death domain (TRADD), Fas-associated death domain (FADD), Caspase-8, BH3-interacting domain death agonist (Bid), Bcl-2-associated X protein (Bax), Bcl-2 homologous antagonist/killer (Bak), B-cell lymphoma-2 (Bcl-2), Cytochrome-c (Cytc), apoptotic protease activating factor-1 (APAF1), Caspase-9, and Caspase-3), immune-related genes (interferon-γ (IFN-γ), interleukin-2 (IL-2), IL-4, IL-6, IL-1β, IL-10, transforming growth factor-β1 (TGF-β1), IL-17, IL-21, and IL-22), heat shock protein (HSP) genes (HSP25, HSP40, HSP60, HSP70, HSP90, and HSP110), as well as miR-27b-3p. Western blot was used to determine protein levels of apoptosis-related factors (TNF-α, Caspase-8, Bcl-2, Caspase-9, and Caspase-3), as well as HSPs (HSP40, HSP60, HSP70, and HSP90). The results indicated that TRADD, FADD, and APAF1 were target genes of miR-27b-3p, as well as miR-27b-3p participated in molecular mechanism of apoptosis through targeting TNF-α/TNFR1/Caspase-8 death receptor pathway-triggered Bid/Cytc/Caspase-9 mitochondrial pathway in ammonia-treated chicken PBLs. In addition, our findings demonstrated that excess ammonia led to immunosuppression via Th1/Th2 imbalance and Treg/Th17 imbalance. Simultaneously, ammonia stress activated HSPs. In summary, for the first time, our data demonstrated that HSPs-triggered immunosuppression led to apoptosis under ammonia exposure. Our findings provided a new insight into molecular mechanism of ammonia poisoning and an important reference for environmental risk assessment related to ammonia.

Chlorpyrifos triggers epithelioma papulosum cyprini cell pyroptosis via miR-124-3p/CAPN1 axis

Chlorpyrifos (CPF), a widely used organophosphorus pesticide has caused water pollution, threatening aquatic organisms. MicroRNAs (miRNAs) highly conserved noncoding RNAs, that regulate various cell death processes, including pyroptosis. To investigate the effect of CPF exposure on epithelioma papulosum cyprini (EPC) cell pyroptosis and the role of the miR-124-3p/CAPN1 axis, we established miR-124 overexpression and inhibition EPC cell models of CPF exposure. The target of the miR-124-3p/CAPN1 axis was primarily confirmed by the double luciferase reporter assay. Pyroptosis was demonstrated to occur in CPF-exposed EPC cells and was accompanied by mitochondrial membrane potential depletion, ROS level elevation and pyroptotic indicator expression upregulation. PD150606 was supplied as a CAPN1 inhibitor, alleviating CPF-induced mitochondrial dysfunction, and alleviating the increased expression of NLRP3, CASP1, IL1β and GSDMD. In conclusion, CPF induces pyroptosis by regulating the miR-124-3p/CAPN1 axis. This study enriches the cytotoxicity study of CPF, and provides new theoretical fundamentals for exploration of miRNA and its target protein response to water contaminants.

Heat shock proteins took part in oxidative stress-mediated inflammatory injury via NF-κB pathway in excess manganese-treated chicken livers

Manganese (Mn) is an essential metal in humans and animals. However, excess Mn entered environment due to the wide application of Mn in industry and agriculture, and became an environmental pollutant. Exposure to high doses of Mn is toxic to humans and animals (including chickens). Liver is a target organ of Mn poisoning. Nevertheless, there were few studies on whether Mn poisoning damages chicken livers and poisoning mechanism of Mn in chicken livers. Herein, the aim of this study was to explore if oxidative stress, heat shock proteins (HSPs), and inflammatory response were involved in the mechanism of Mn poisoning-caused damage in chicken livers. A chicken Mn poisoning model was established. One hundred and eighty chickens were randomly divided into one control group (containing 127.88 mg Mn kg^-1) and three Mn-treated groups (containing 600, 900, and 1800 mg Mn kg^-1, respectively). Histomorphological structure was observed via microstructure and ultrastructure. Spectrophotometry was used to detect total antioxidant capacity (T-AOC) and inducible nitric oxide synthase (iNOS) activity, as well as nitric oxide (NO) content. And qRT-PCR was performed to measure mRNA expression of inflammatory genes (nuclear factor kappa B (NF-κB), tumor necrosis factor α (TNF-α), cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), and iNOS) and heat shock protein (HSP) genes (HSP27, HSP40, HSP60, HSP70, and HSP90). Multivariate correlation analysis, principal component analysis, and cluster analysis were used to demonstrate the reliability of mechanism of Mn poisoning in our experiment. The results indicated that excess Mn led to inflammatory injury at three contents and three time points. Meanwhile, we found that NO content, iNOS activity, and NF-κB, TNF-α, COX-2, PGE2, and iNOS mRNA expression increased after Mn treatment, meaning that exposure to Mn induced inflammatory response via NF-κB pathway in chicken livers. Moreover, excess Mn decreased T-AOC activity, indicating that Mn exposure caused oxidative stress. Furthermore, mRNA expression of above five HSP genes was up-regulated during Mn exposure. Oxidative stress triggered the increase of HSPs and the increase of HSPs mediated inflammatory response induced by Mn. In addition, there were time- and dose-dependent effects on Mn-caused chicken liver inflammatory injury. Taken together, HSPs participated in oxidative stress-mediated inflammatory damage caused by excess Mn in chicken livers via NF-κB pathway. For the first time, we found that oxidative stress can trigger HSP70 and HSPs can trigger poisoning-caused inflammatory damage, which needs to be further explored. This study provided a new insight into environmental pollutants and a reference for further study on molecular mechanisms of poisoning.

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.

Th1/Th2 imbalance and heat shock protein mediated inflammatory damage triggered by manganese via activating NF-κB pathway in chicken nervous system in vivo and in vitro

Manganese (Mn) is a ubiquitous heavy metal pollutant in environment, and excess Mn can damage nervous system of humans and animals. However, molecular mechanism of Mn-induced poultry neurotoxicity on inflammatory injury is still not fully clear. Thus, the purpose of the conducted research was to explore molecular mechanism of inflammatory injury caused by Mn in chicken nervous system. Two Mn poisoning models were established in vivo and in vitro. One hundred and eighty chickens were randomly separated into four groups. One control group was raised drinking water and standard diet. Three Mn groups were raised drinking water, and the standard diet supplemented with three different concentrations of MnCl2 ∙ 4H2O. There were 45 birds and 3 replicates in each group. Neurocytes from chicken embryos were cultured in mediums without and with six different concentrations of MnCl2 ∙ 4H2O in vitro. Our experiments showed that excess Mn caused cerebral histomorphological structure alternations and damage, and increased the expressions (P < 0.05) of inflammation-related factor NF-κB, TNF-α, iNOS, COX-2, and PTGEs in vivo and in vitro, meaning that excess Mn caused inflammatory damage and inflammatory response in chicken nervous system. Moreover, there were an upregulated IFN-γ mRNA expression and a downregulated IL-4 mRNA expression (P < 0.05) in bird cerebra and embryonic neurocytes after exposure to Mn, indicating that Mn exposure caused Th1/Th2 imbalance and immunosuppression. Additionally, in our research, the elevation (P < 0.05) of five HSPs (HSP27, HSP40, HSP60, HSP70, and HSP90) was found, suggesting that HSPs participated molecular mechanism of Mn stress. In addition, the inflammatory toxicity of Mn to chicken nervous system was time- and dose-dependent. Taken all together, our findings indicated that Th1/Th2 imbalance and HSPs mediated Mn-caused inflammatory injury via NF-κB pathway in chicken nervous system in vivo and in vitro.

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.

Cadmium-induced Oxidative Stress and Immunosuppression Mediated Mitochondrial Apoptosis via JNK-FoxO3a-PUMA pathway in Common Carp (Cyprinus carpio L.) Gills

Cadmium (Cd)-caused water environment pollution has become a matter of concern. Gill is an organ with respiratory and mucosal immune functions, and is also one of the organs directly attacked by pollutants. It was found that excess Cd could cause Cd accumulation and gill injury in carp. However, the mechanism of Cd-caused damage in common carp gills is still unclear. Oxidative stress, immunosuppression, and apoptosis took part in the mechanism of poisoning caused by some harmful substances. The aim of the study was to investigate complex molecular mechanism of apoptotic injury caused by Cd in common carp gills. Hence, in this study, we established a Cd poisoning model to explore whether excess Cd can induce apoptosis through observing histomorphology and apoptotic cells; and determining mineral elements, oxidative stress-related factors, immune-related, and apoptosis-related genes in common carp gills. Fifty-four fish were randomly separated into the control group and the Cd group and were cultured for 45 days. The water of the control group was drinking water and the water of the Cd group was CdCl₂-added drinking water (0.26 mg/L Cd). In our results, we found that excess Cd increased Cd level, decreased the levels of essential mineral elements (Cu, Fe, Zn, and Mn), damaged mitochondria, and increased apoptotic cells in common carp gills, meaning that excess Cd caused Cd accumulation and apoptotic injury via mitochondrion in common carp gills. Furthermore, we found that Cd inhibited anti-apoptosis-related gene Bcl-2 and stimulated pro-apoptosis-related genes (JNK, FoxO3a, PUMA, Bax, Apaf-1, Caspase-9, and Caspase-3) on 15th, 30th, and 45th days. Above data meant that Cd exposure caused apoptosis via mitochondrion and JNK-FoxO3a-PUMA pathway in common carp gills. In addition, in our experiment, Cd treatment increased oxidants (H₂O₂ and MDA) and decreased antioxidants (CAT, GPx, GST, SOD, T-AOC, and GSH), indicating that Cd caused oxidative stress via oxidation/antioxidation imbalance. Meanwhile, compared to the control group, T-help 17 (Th17) cell-related factors (IL-17, TNF-α, and RORγ) were up-regulated, regulatory T (Treg) cell-related factors (IL-10 and Foxp3) were down-regulated, and IL-17/IL-10, TNF-α/IL-10, and RORγ/Foxp3 were increased in Cd-exposed group; meaning that excess Cd induced immunosuppression via the imbalance of Th17/Treg cells. Taken together, our findings indicated that JNK-FoxO3a-PUMA pathway and mitochondrion participated in oxidative stress and immunosuppression-mediated apoptosis caused by Cd in common carp (Cyprinus carpio L.) gills. Our data provided new perspectives on the negative effects of heavy metal pollutants on fish.

Corn stover biochar increased edible safety of spinach by reducing the migration of mercury from soil to spinach

Mercury (Hg) is toxic and can affect human health through soil entering food chain. Spinach absorb easily heavy metals. Corn stover biochar can improve soil structure and physicochemical property. This study wanted to establish a Hg-corn stover biochar-soil-spinach model including 1 control group (without HgCl₂ and corn stover biochar) and 24 treatment groups (with HgCl₂ or/and corn stover biochar). Hg concentration was 0, 1, 2, 4, and 6 mg kg^-1, respectively. Corn stover biochar contents were 0%, 1%, 3%, 5%, and 7% w/w, respectively. The results showed that residual Hg concentrations was the largest and water soluble and exchangeable Hg as well as carbonate bound Hg concentrations were the lowest among five Hg forms. Hg concentrations in four Hg treatment groups were higher than the control group in dose-dependent manner. The deposition of 6 mg kg^-1 Hg was the highest. Corn stover biochar decreased Hg migration from soil to leaching solution and spinach, and passivation effect of 7% concentration of corn stover biochar was the best. Besides, corn stover biochar relieved the increase of methyl Hg caused by Hg in soil. Moreover, Hg concentration in roots was the highest and Hg concentration in stems was the lowest in spinach. Furthermore, Hg absorbed by roots was more than the sum of Hg absorbed by stems and leaves. In addition, we also found that the measured soil Hg concentrations were coincided with the predicted soil Hg concentrations under 1, 2, and 4 mg kg^-1 Hg concentrations, except 2 mg kg^-1 Hg at 7% C. Under 6 mg kg^-1 Hg concentration, measured soil Hg concentrations was lower than that of the predicted soil Hg concentrations. Taken together, our findings indicated that corn stover biochar can increase edible safety of spinach by immobilizing Hg in soil and be used as an organic amendment.

NLRP3 inflammasome is involved in the mechanism of mitigative effect of selenium on lead-induced inflammatory damage in chicken kidneys

Lead (Pb) is a kind of widespread toxic environmental pollutant which can cause harm to organisms. Selenium (Se) has the property of mitigating Pb toxicity through decreasing oxidative stress and inflammation caused by Pb. Nucleotide-binding domain, leucine-rich-containing family, and pyrin-domain containing-3 (NLRP3) inflammasome involve in inflammation process. However, the effect of NLRP3 inflammasome in heavy metal-caused animal damage remains unknown. This research aimed to explore the mechanism of mitigative role of Se on Pb-caused renal inflammatory injury in chickens. One-week-old male chickens were provided a standard diet and drinking water, a standard diet added with 1 mg kg^-1 of Se and drinking water, a standard diet and drinking water added with 350 mg L^-1 Pb, and a standard diet added with 1 mg kg^-1 Se and drinking water added with 350 mg L^-1 Pb. On the 4th, 8th, and 12th weeks, serum was used to measure creatinine (CREA) and uric acid (UA) contents, and kidneys were used to measure Se and Pb concentrations, histological structure, oxidative stress indicators, relative expressions of cytokines, and inflammatory factors. The results showed that Pb accumulated, Se concentration decreased, CREA and UA contents increased, and renal injury occurred in Pb-treated chicken kidneys. Excess Pb increased MDA content and the expressions of IL-1β, IL-6, IL-17, NLRP3, caspase-1, NF-κB, COX-2, TNF-α, and PTGEs and decreased GSH content, GPx and SOD activities, and IFN-γ expression in the chicken kidneys. Se administration alleviated the aforementioned changes. In addition, toxic effect of Pb on the chicken kidneys was time-dependent. NLRP3 inflammasome, caspase-1, and IL-1β may be sensitive indicators in Pb-induced chicken kidney inflammatory damage. In conclusion, NLRP3 inflammasome took part in antagonistic role of Se against Pb-caused inflammation via changing oxidative stress indicators, cytokines, and inflammation-related genes in the chicken kidneys.

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.

Expression of PD-L1 for predicting response to immune checkpoint inhibitors in metastatic urothelial carcinoma: a systematic review and meta-analysis

Background

We conducted this meta-analysis and systematic literature review to study the ability of PD-L1 to predict objective response in patients with urothelial cancer treated with PD-1/PD-L1 inhibitors.

Methods

Relevant studies of PD-1 or PD-L1 inhibitors in urothelial cancer that reported objective response rate (orr) based on PD-L1 expression status in PubMed, embase, and the Cochrane Library were retrieved. Efficacy of PD-L1 expression status in predicting orr and the efficacy, safety of PD-1 and PD-L1 drugs were analyzed.

Results

Studies were divided into ≥1%, ≥5%, and ≥25% based on PD-L1 positivity threshold, and the patients were grouped into PD-L1 positive and negative. In all 3 expression thresholds, patients with positive PD-L1 expression were more likely to experience an objective response [≥1% threshold odds ratio (or): 1.74; 95% confidence interval (ci): 1.20 to 2.53; ≥5% threshold or: 2.74; 95% ci: 2.01 to 3.724; ≥25% threshold or: 7.13; 95% ci: 2.38 to 21.40] in comparison with patients with negative PD-L1 expression. Of the 3 thresholds, the ≥25% threshold was better in predicting orr (1.74 vs. 2.93 vs. 7.13; p < 0.0001). The ≥1% PD-L1 threshold had a relatively high sensitivity in predicting orr; the ≥5% PD-L1 threshold was better for specificity. Sensitivity was higher at the ≥25% threshold than at the other two thresholds, but specificity was lower. Further, we found that there is no statistically significant difference in efficacy between PD-1 and PD-L1 drugs.

Conclusions

Urothelial cancer patients with PD-L1 positive expression responded better than PD-L1 negative patients did, and a threshold of ≥5% or greater for PD-L1 expression might predict positive clinical response.

PTEN/AKT/mTOR pathway involvement in autophagy, mediated by miR-99a-3p and energy metabolism in ammonia-exposed chicken bursal lymphocytes

Emission of atmospheric ammonia (NH₃) is an environmental challenge because of its harmful effects on humans and animals including birds. Among all organisms, NH₃ is highly sensitive to birds. Autophagy plays a critical role in Bursa of fabricius (BF)-mediated immune responses against various hazardous substances. Therefore, we designed our work to demonstrate whether NH₃ can induce autophagy in broiler chicken BF. In this study, the downregulated levels of mammalian target of rapamycin and light chain-3 (LC-Ⅰ), as well as the upregulated levels of phosphate and tensin homology (PTEN), protein kinase B (AKT), autophagy related-5, light chain-3 (LC3-Ⅱ), Becline-1, and Dynein, were found. Our results of transmission electron microscopy displayed signs of autophagosomes/autophagic lysosomes, and immunofluorescence assay displayed that NH₃ exposure reduced the relative amount of CD8⁺ B-lymphocyte in chicken BF. Exposure of NH₃ led to energy metabolism disturbance by decreasing mRNA levels of glucose metabolism factors aconitase-2, hexokinase-1, hexokinase-2, lactate dehydrogenase-A, lactate dehydrogenase-B, pyruvate kinase, phosphofructokinase and succinate dehydrogenase complex unit-B, and adenosine triphosphates (ATPase) activities (Na⁺/K⁺ ATPase, Ca²⁺ ATPase, Mg²⁺ ATPase, and Ca/Mg²⁺ ATPase). Moreover, phosphate and tensin homology was found as target gene of microRNA-99a-3p which confirmed that high concentration of NH₃ caused autophagy in chicken BF. In summary, these findings suggested that ammonia induced autophagy via miR-99a-3p, the reduction of ATPase activity, and the alteration of autophagy-related factors, and energy metabolism mediation in BF. Our findings provide information to assess the harmful effects of NH₃ on chicken and clues for human health pathophysiology.

MiR-7a ameliorates spinal cord injury by inhibiting neuronal apoptosis and oxidative stress

OBJECTIVE

The aim of this study was to investigate the therapeutic effect of microRNA-7a (miR-7a) on spinal cord injured rats and to explore its underlying mechanism in vivo.

MATERIALS AND METHODS

The spinal cord injury (SCI) model was first established in adult rats. The epicenter of the lesion was treated with miR-7a mimics via intrathecal injection. The Basso-Beattie-Bresnahan (BBB) locomotor rating scale was used to evaluate the functional recovery of hindlimbs in rats within 4 weeks following SCI. Western blotting and qPCR were utilized to detect the apoptosis and oxidative stress in rats treated with or without miR-7a. In addition, the neuron survival and neuro-filament amount were determined using immunofluorescence.

RESULTS

After SCI and miR-7a treatment, the locomotor recovery of treated rats was significantly improved when compared with rats without treatment. The mitochondrial disorder and cell death were significantly reduced in miR-7a treated rats. Meanwhile, the nuclear transcription factor-κB (NF-κB) pathway was significantly reduced as well. Contrarily, the expression of anti-apoptotic protein Bcl-2 and NF-κB inhibitor I-κB was remarkably elevated in miR-7a treated rats. In addition, up-regulation of miR-7a rescued neurons and maintained the neural structure.

CONCLUSIONS

The up-regulation of miR-7a alleviated the injury-induced oxidative stress and inhibited apoptosis by down-regulating NF-κB pathway in SCI rats.

Oxidative stress and mitochondrial dysfunction involved in ammonia-induced nephrocyte necroptosis in chickens

Ammonia (NH₃), an environmental pollutant, poses a serious threat to human and avian health. Although previous studies have showed that NH₃ caused kidney injury, the molecular mechanisms of nephrotoxicity induced by NH₃ remain unclear. To explore the mechanisms of NH₃ nephrotoxicity, a total of 36 broiler chicks at one day of age were exposed to NH₃. After 42 days of exposure, blood samples were collected to determine creatinine and uric acid; and kidney samples were weighted and then collected to detect ultrastructural changes, oxidative stress parameters, ATPases, necroptosis- and mitochondrial dynamics-related genes. The results showed that chickens exposed to NH₃ showed lower relative kidney weight and an increase concentration in serum creatinine and uric acid. NH₃ exposure caused nephrocyte necrosis and increased the expression of necroptosis-related genes (TNF-α, RIPK1, RIPK3, MLKL, and JNK). Besides, the activities of antioxidant systems (SOD, CAT, GSH-Px, and T-AOC) were reduced, whereas the concentrations of H₂O₂ and MDA were elevated. Lower activities of ATPases were obtained in NH₃ treatment groups. Furthermore, the mitochondrial fission-related genes drp1 and mff were activated, and mitochondrial fusion-related genes opa1, mfn1 and mfn2 were suppressed after NH₃ exposure. Based on the above results, we conclude that NH₃ caused-oxidative stress and mitochondrial dysfunction mediated nephrocyte necroptosis in chickens. This study may provide new insight into NH₃ nephrotoxicity.

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.

NF-κB pathway took part in the development of apoptosis mediated by miR-15a and oxidative stress via mitochondrial pathway in ammonia-treated chicken splenic lymphocytes

Ammonia, a kind of gas with pungent smell, is harmful to livestock and people, and has bad influence on the atmosphere. However, the mechanism of splenic toxicity caused by ammonia is still poorly understood. The aim of present study was to investigate the effect of ammonia on chicken splenic lymphocytes from the perspective of apoptosis. Chicken splenic lymphocytes were divided into the control group and the two ammonium treatment groups (1 mmol/L and 5 mmol/L ammonia), and were cultured for 24 h. CCK-8, flow cytometry (FC), fluorescence microscope, quantitative real-time PCR (qRT-PCR), and Western blot were used to study the differences between different groups. The results showed that ammonia exposure increased the release of calcium (Ca)²⁺ and reactive oxygen species (ROS) from mitochondrion. Besides, we found an increase in mRNA levels of glutathione peroxidase (GPx), inflammation-related genes (nuclear factor-κB (NF-κB), cyclooxygenase-2 (COX-2), inducible nitric (iNOS), tumor necrosis factor-α (TNF-α), and transforming growth factor-β (TGF-β)), apoptosis-related genes (B-cell lymphoma-2 (BCL-2), Bcl-2 associated X protein (BAX), Cytochrome c (Cytc), apoptotic protease activating factor 1 (APAF1), Caspase-9, and Caspase-3), and an increase in protein levels of NF-κB, iNOS, BAX, Cytc, Caspase-9, and Caspase-3. At the same time, we found a decrease level of GPx protein expression, and a decrease level of glutathione S-transferase (GST) mRNA expression, and a decrease level of heme oxygenase-1 (HO-1) and BCL-2 mRNA and protein expression in splenic lymphocytes exposed to ammonia. Meanwhile, miR-15a expression increased under ammonia exposure. In summary, these results indicated that ammonia induced oxidative stress, promoted the release of Ca²⁺, Cytc, and ROS from mitochondria, and then induced mitochondria-mediated inflammatory response, finally triggered apoptosis in chicken splenic lymphocytes.

Ammonia-triggered apoptosis via immune function and metabolic process in the thymuses of chickens by proteomics analysis

Ammonia (NH₃), an environmental pollutant with a pungent odor, is not only an important volatile in fertilizer production and ranching, but also main basic component of haze. In present study, we found that ultrastructural changes and 3167 differentially expressed proteins (DEPs) using proteomics analysis in the thymuses of chickens exposed to NH₃ on day 42. Obtained DEPs were enriched using GO and KEGG; and 66 DEPs took part in immune function, metabolic process, and apoptosis in the thymuses of chickens treated with NH₃. 9 genes of DEPs were validated using qRT-PCR, and mRNA expression of 2 immune-related genes (CTSG and NFATC2), 3 metabolic process-related genes (APOA1, GOT1, and GOLGA3), and 4 apoptosis-related genes (PIK3CD, CTSS, CAMP, and NSD2) were consistent with DEPs in chicken thymuses. Our results indicated that excess NH₃ led to immunosuppression, metabolic disorder, and apoptosis in chicken thymuses. Present study gives a novel insight into the mechanism of NH₃ toxicity and demonstrated that immune response, metabolism process, and apoptosis were important in the mechanism of NH₃ toxicity of chicken exposure to high concentration of NH₃.

Whole transcriptome-based miRNA-mRNA network analysis revealed the mechanism of inflammation-immunosuppressive damage caused by cadmium in common carp spleens

Cadmium (Cd) is a well-known environmental pollutant and can damage fish. MicroRNAs (miRNAs) can involve in inflammation and immunosuppression. However, the mechanisms of miRNAs are still unclear in common carp (Cyprinus carpio L.) treated by Cd. In current study, 54 juvenile common carp were randomly divided into the control group and the Cd group (0.26 mg L^-1 Cd) and were cultured for 30 days. The results revealed inflammatory damage in the spleens of common carp after Cd exposure using morphological construction. There were 23 differentially expressed miRNAs including 17 up-regulated differentially expressed miRNAs (miR-1-4-3p, miR-7-1-5p, miR-7-2-5p, miR-10-43-5p, miR-34-3-5p, miR-128-4-3p, miR-128-5-3p, miR-132-2-5p, miR-132-6-5p, miR-216-3-5p, miR-216-4-5p, miR-375-2-3p, miR-375-4-3p, miR-375-5-3p, miR-375-7-3p, miR-375-8-3p, and miR-724-5p) and 6 down-regulated differentially expressed miRNAs (miR-9-6-5p, miR-25-9-3p, miR-31-3-5p, miR-31-12-5p, miR-103-5-5p, and miR-122-1-3p). The 23 miRNAs regulated 2022 target mRNAs. There were 10 pathways and 9 annotation clusters on 2022 target mRNAs using KEGG and GO analysis, respectively. Among them, 5 pathways (NF-κB signaling pathway, Jak-STAT signaling pathway, MAPK signaling pathway, Th1 and Th2 cell differentiation, and Toll-like receptor signaling pathway) and 7 GO terms (negative regulation of immune system process, T cell mediated immunity, regulation of immune response, inflammatory response, positive regulation of inflammatory response, regulation of inflammatory response, and inflammasome complex) were associated with inflammatory response and immunosuppression. miR-375-4-3p, NF-κB, COX-2, PTGES, and IL-4/13A increased and miR-31-12-5p, miR-9-6-5p, MMP9, IL-11, SPI1, and T-Bet decreased using transcriptome sequencing and RT-qPCR in Cd-treated common carp spleens, which revealed that our results were reliable. Our data indicated that miRNAs mediated inflammation-immunosuppressive injury caused by Cd in common carp spleens using whole transcriptome-based miRNA-mRNA network analysis. Our study provided new insights into the toxicology of Cd exposure.

Ammonia inhalation-induced inflammation and structural impairment in the bursa of fabricius and thymus of broilers through NF-κB signaling pathway

Ammonia (NH₃) is a toxic, environmental pollutant, and irritant gas. Previous studies reported the toxic effects of NH₃ which led to inflammation in various organs of chicken. However, the exact mechanism of NH₃-induced inflammation in chicken lymphoid organs bursa of fabricius (BF) and thymus is still elusive. Thus, this study was designed to investigate NH₃-induced inflammation in chicken BF and thymus. Experimental chickens were divided into low (5.0 mg/m³), middle (10.0-15.0 mg/m³), and high (20.0-45.0 mg/m³) NH₃-treated groups. To investigate NH₃-induced inflammation in chicken's BF and thymus, histological observation, NO content and iNOS activity, inflammatory cytokine contents, and mRNA levels were performed by light microscopy, microplate spectrophotometer, ELISA assay, and qRT-PCR. The finding of the present study showed that NH₃ exposure reduced BF and thymus index, increased nitric oxide (NO) content and inducible nitric oxide synthase (iNOS) activity, inflammatory cytokine contents and mRNA levels of nuclear factor-kappa B (NF-κB), cyclooxygenase-2 (Cox-2), tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), IL-10, IL-1β, IL-18, toll-like receptor 2A (TLR-2A), and iNOS. Histopathological examination revealed signs of inflammation including increased nuclear debris and vacuoles in the cortex and medulla of thymus and bursal follicles. Conclusively, our findings displayed that NH₃ exposure affects the normal function of BF and thymus and led inflammation. The data provided a new ground for NH₃-induced toxicity and risk assessment in chicken production.

Ammonia inhalation impaired immune function and mitochondrial integrity in the broilers bursa of fabricius: Implication of oxidative stress and apoptosis

Ammonia (NH₃) is considered as environmental pollutant and toxic agent for animals and humans including poultry. Previous reports demonstrated that NH₃ suppressed broilers immunity. However, the harmful effects of NH₃ on broilers bursa of fabricius (BF) is still unknown. Functionally, apoptosis is very important for many physiological processes including homeostasis of lymphocyte population. Therefore, the present study was aimed to investigate the underlying mechanisms of NH₃ toxicity in the broilers BF. Histological observation showed lymphocyte accumulation, cavities and increased interstitial cells in BF. Ultrastructural observation indicated mitochondrial vacuoles, deformation and disappearance of mitochondrial membranes. Oxidative stress markers (CAT, MDA, H₂O₂, GGT, GSH-Px and GSH) showed that NH₃-induced oxidative stress in BF. Meanwhile, Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay revealed increased apoptotic cells. In addition, the mRNA and protein expression of dynamin-related protein 1 (Drp1), mitochondrial fission factor (Mff), mitofusin 1 and 2 (Mfn1 and Mfn2), optic atrophy 1 (Opa1) indicated imbalance between mitochondrial inner and outer membrane and results in mitochondrial dysfunction in broilers BF. The mRNA and protein expression of apoptosis-related genes including Caspase-3, Caspase-9, Caspase-8, Cytochrome-C (Cyt-C), p53, B-cell lymphoma 2 (Bcl-2) and Bcl-2 associated X protein (Bax) were significantly altered in broilers BF. Conclusively, these results displayed that excessive NH₃ causes BF damage and mitochondrial dysfunction through oxidative stress and apoptosis in BF and could affect immune function of BF. These findings provide possible therapeutic targets to prevent NH₃ induced toxicity in the BF of broilers.

Improved quantitative assessment of HBV-associated liver fibrosis using second-harmonic generation microscopy with feature selection

BACKGROUND AND AIM

Quantitative assessments of liver fibrosis using second-harmonic generation/two-photon excited fluorescence microscopy provide greater sensitivity and accuracy than collagen proportionate area while eliminating operator-dependent variation in the staining process. In conjunction with sophisticated image analysis algorithms and feature selection, we might reduce the computation cost in future and narrow down the candidates for further clinical studies.

METHODS

We sampled a total of 244 liver specimens from patients with hepatitis B viral infections who underwent liver biopsy or liver resection at the National Taiwan University Hospital. The samples were then imaged using a Genesis (HistoIndex Pte. Ltd, Singapore) system, wherein second-harmonic generation microscopy was used to visualize collagen, and two-photon excited fluorescence microscopy was used to visualize other cell structures. We used 100 morphological features extracted from the images to assess correlations with METAVIR fibrosis scores.

RESULTS

Out of 100 quantitative measurements, 76 showed significant correlation with METAVIR scoring, thereby enabling the statistical discrimination of patients in various stages of the disease. These 76 features were also narrowed down by the nonlinear test to 10 candidate measurements, which can be further investigated in detail.

CONCLUSIONS

Our experimental results showed that the model with 10 selected features can beat the one with second-harmonic generation only, and performed equivalently well compared the model with 76 features, especially for early-stage discrimination. Features presenting significant correlation were used to fit a single combined index in order to predict pathological staging, thereby making it possible to reveal incremental progress during treatment.

miR-187-5p/apaf-1 axis was involved in oxidative stress-mediated apoptosis caused by ammonia via mitochondrial pathway in chicken livers

Ammonia (NH₃), a toxic gas, is an important cause of atmospheric haze and one of the main pollutants in air environment of poultry houses, threatening the health of human beings and poultry. However, little is known about the effect of NH₃ on liver apoptotic damage. This study aimed to investigate the mechanism of oxidative stress-mediated apoptosis caused by NH₃ in chicken livers and whether miR-187-5p/apaf-1 axis was involved in this mechanism. Here we duplicated NH₃ poisoning model of chickens for fattening to study the ultrastructure of chicken livers, apoptosis rate, oxidative stress indexes, miR-187-5p, and apoptosis-related genes. Obvious apoptotic characteristics of liver tissues exposed to excess NH₃ were observed, and the apoptosis rate increased. Excess NH₃ decreased the activities of catalase (CAT), superoxide dismutase (SOD), total antioxidant capacity (T-AOC) and glutathione peroxidase (GSH-Px), and increased the content of malondialdehyde (MDA), suggesting that oxidative stress occurred. miR-187-5p decreased, and apoptotic protease activating factor-1 (apaf-1) increased, indicating that excess NH₃ dysregulated miR-187-5p/apaf-1 axis. The expression of tumor protein p53 (p53), Bcl-2 associated X protein (Bax), Bcl-2 homologous antagonist/killer (Bak), Cytochrome-c (Cyt-c), Caspase-9, Caspase-8, and Caspase-3 was promoted, and the expression of B-cell lymphoma-2 (Bcl-2) was inhibited, resulting in apoptosis. Moreover, oxidative stress indexes, miR-187-5p, and apoptosis-related genes changed in dose- and time-dependent manner. Altogether, miR-187-5p/apaf-1 axis participated in oxidative stress-mediated apoptosis caused by NH₃ via mitochondrial pathway in the livers of chickens for fattening. This study may provide new ideas to study the mechanism of liver apoptotic damage induced by NH₃ exposure.

Olfactory ensheathing cells facilitate neurite sprouting and outgrowth by secreting high levels of hevin

Transplantation of olfactory ensheathing cells (OECs) has been shown to enhance synapse formation. However, the mechanisms underlying this effect are not completely understood. We performed profiling of the OEC and astrocyte secretomes via a proteomics approach, in case hevin secreted by astrocytes might be involved in the formation of synapses. Semi-quantitative proteomic analysis revealed that 25 proteins were highly expressed, and 22 were weakly expressed in OEC conditioned medium compared with astrocyte conditioned medium. These molecules are highly associated with neural differentiation and regeneration, enzyme regulatory activity, and growth factor binding. The quantification data of clusterin, fibronectin, hevin, insulin-like growth factor binding protein 2 and secreted protein acidic and rich in cysteine were further confirmed by western blotting. Moreover, the addition of hevin in the culture medium improved neurite sprouting and outgrowth of differentiated neural stem cells. The greater expression of hevin in OEC conditioned medium than in astrocyte conditioned medium was associated with a greater capacity of synaptic formation. Thus, our results indicate that soluble factors secreted by OECs provide a permissive environment for nerve repair, and hevin is one of the key molecules facilitating neurite sprouting and outgrowth.

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

Ammonia is a known environmental pollutant around the world. It leads to the deterioration of air quality and has adverse effects on human health. Although previous studies have demonstrated that ammonia caused some health problems to chickens, it is still unclear whether ammonia causes cardiac toxicity. The functional autophagy is very important for cardiac homeostasis. Therefore, the role of autophagy was investigated in the mechanism of chicken heart damage induced by environmental contaminant ammonia in our present study. The results from the oxidative stress index (SOD, GPx, H₂O₂, and MDA), NO content, iNOS activity, and transmission electron microscopy indicated that excess ammonia induced oxidative stress and autophagy in the chicken heart. The expression results from miR-202-5p and PTEN/AKT/mTOR (PTEN, LC3-I, LC3-II, p-AKT, AKT, Beclin1, Dynein, ATG5, p-mTOR and mTOR) signaling pathway-related genes further confirmed that excess ammonia induced cardiac autophagy. In conclusion, these results demonstrated that excess ammonia can cause cardiac damage and mediate mir-202-5p to regulate autophagy through PTEN/AKT/mTOR pathway in the chicken heart injury. Our findings will provide a new insight for better assessing the toxicity mechanism of environmental pollutants ammonia on the heart.