Resistin alleviates lipopolysaccharide-induced inflammation in bovine alveolar macrophages by activating the AMPK/mTOR signaling pathway and autophagy.

Objective: Resistin (RETN) is an adipocyte-specific hormone that participates in metabolism and modulates cellular inflammation. Our study aimed to assess the effects of RETN treatment on autophagy and the underlying molecular and biological mechanisms in bovine alveolar macrophages (BAMs). Methods: The optimal concentration of RETN + lipopolysaccharide (LPS) on macrophages was screened and then used to co-culture with alveolar macrophages. Autophagosomes in BAMs were examined using a transmission electron microscope (TEM). Quantitative real-time PCR (qRT-PCR) was used to detect the mRNA expression of microtubule-associated protein light chain 3 (LC3) and p62. Western blot (WB) was used to detect the protein expressions of LC3 and p62. The distribution of LC3 and p62 proteins in the cells was observed by immunofluorescence (IF). The concentrations of interleukin (IL)-1ß, IL-6, and tumor necrosis factor-alpha (TNF-α) were detected using enzyme-linked immunosorbent assay (ELISA). The protein expression of adenosine-monophosphate-activated protein kinase (AMPK), p-AMPK, mammalian target of rapamycin (mTOR), and p-mTOR was detected using WB. Results: The treatment of BAMs with RETN or LPS increased the number of autophagosomes and the ratio of LC3II/LC3I and decreased the expression level of p62 protein. RETN treatment significantly triggered autophagy compared to LPS treatment. Moreover, the ratios of p-AMPK/AMPK and p-mTOR/mTOR were upregulated and downregulated, respectively, after RETN treatment, suggesting that AMPK/mTOR signaling pathway activation is required for RETN-mediated autophagy in BAMs. Additionally, the ratio of LC3-II/LC3-I was lower, and the concentrations of IL-1ß, IL-6, and TNF-α significantly decreased in the LPS and RETN co-treatment groups compared to the single LPS treatment group. However, both autophagy- and LPS-induced inflammation were partially alleviated by RETN treatment. Conclusion: RETN can promote autophagy in BAMs by activating the AMPK/mTOR signaling pathway, it may help prevent LPS-induced inflammation.

Effects of isochlorogenic acid A on mitochondrial dynamics imbalance and RLR damage in PAM cells induced by combined mycotoxins.

Mycotoxins have strong immunotoxicity and can induce oxidative stress and mitochondrial dynamics imbalance. Mitochondrial antiviral signaling protein (MAVS) in the RIG-I like receptor (RLR) pathway of innate immunity is located on mitochondria, and whether it is affected by mycotoxins has not been reported yet. This experiment used porcine alveolar macrophages (PAM) to evaluate the antagonism of three isomers of chlorogenic acid (chlorogenic acid, isochlorogenic acid A, and neochlorogenic acid) against combined mycotoxins (Aflatoxin B1, Deoxynivalenol, and Ochratoxin A) induced mitochondrial damage and their effects on the RLR pathway, providing assistance for further elucidating the mechanism of mycotoxin immunotoxicity. Western blotting, enzyme linked immunosorbent assay (ELISA), and flow cytometry were used to detect relevant indicators. All three types of chlorogenic acid treatment can antagonize the cytotoxicity induced by combined mycotoxins, especially isochlorogenic acid A, which can protect cells from mycotoxins damage by maintaining mitochondrial dynamic homeostasis and improving innate immune function related to the RLR pathway.

Development and characterization of an immortalized nasopharyngeal epithelial cell line to explore airway physiology and pathology in yak (Bos grunniens).

Airway epithelial cells play a crucial role in investigating the physiological and pathological mechanisms of the respiratory tract in yaks, a species whose unique respiratory system has garnered extensive interest. Despite this growing interest, there currently are no available airway epithelial cell lines from yaks, underscoring the crucial need to establish a yak respiratory epithelial cell line. Therefore, our objective was to isolate a population of primary yak nasopharyngeal epithelial cells (pYNE) and transform them into immortalized yak nasopharyngeal epithelial cells (iYNE), assessing their suitability as an in vitro model. Employing a combined method of physical elimination and differential adhesion, we successfully isolated a population of high-purity pYNE, and developed an iYNE line through pCI-neo-hTERT plasmid transfection. Karyotype and transmission electron microscopy analyses confirmed that pYNE and iYNE share identical morphologies and structures. Gel electrophoresis and real-time PCR analyses demonstrated that pYNE and iYNE expressed similar levels of KRT18 and CDH1 genes (p ≥ 0.541). Notably, iYNE expressed a significantly high level of TERT gene expression (p < 0.001). Immunofluorescence analysis demonstrated that both cell types expressed Pan-Cytokeratin, ZO-1, and E-cadherin proteins. Furthermore, immunoblotting analysis indicated significantly higher levels of hTERT and Ki67 proteins in iYNE (p < 0.001), and similar levels of Cluadin-3 and Occludin proteins (p ≥ 0.103). Proliferation curve analysis highlighted iYNE's serum-dependency and significantly enhanced proliferation capacities (p < 0.001). Additionally, pYNE and iYNE cells demonstrated comparable susceptibilities to infectious bovine rhinotracheitis virus (IBRV). These findings collectively suggest that the developed iYNE retains the evaluated physiological characteristics of pYNE, making it an appropriate in vitro model. This advancement will facilitate further investigation into the respiratory physiological and pathological mechanisms in yaks.

Matrine and icariin can inhibit bovine viral diarrhoea virus replication by promoting type I interferon response in vitro.

Introduction: Bovine viral diarrhoea virus (BVDV) can cause diarrhoea (BVD) in an animal herd, leading to heavy economic losses. There are limited drugs available for treating and controlling BVD. This research aims to investigate the antiviral and immunoregulatory effects of two traditional Chinese herb extracts against BVDV infection. The extracts are matrine and icariin, which have been proved to have immunostimulant and antiviral effects. Material and Methods: A cell counting kit-8 assay was used to analyse the toxicity of matrine and icariin to Madin-Darby bovine kidney (MDBK) cells. The model of MDBK cells infected with BVDV was utilised to uncover the antiviral mechanism of matrine and icariin, which along with their immunoregulatory ability was evaluated by quantitative reverse-transcription PCR and ELISA. Results: The results showed that matrine and icariin can significantly inhibit the gene expression level of the BVDV 5' untranslated region through various pathways. Both matrine and icariin can statistically upregulate the gene expression level of interferon alpha, interferon beta (IFN-ß), toll-like receptor 3, retinoic acid-inducible gene I and interferon regulatory factor 3, and raise the concentration of IFN-ß after BVDV infection. Conclusion: This study proves that both matrine and icariin have inhibitory effects on BVDV replication by activating IFN production and the IFN signalling pathway. The finding is promising and should open up the possibility of larger-scale in vitro research followed by in vivo experiments evaluating matrine and icariin as therapeutic agents in BVD cases.

Molecular Regulatory Mechanism of Nano-Se Against Copper-Induced Spermatogenesis Disorder.

Selenium nanoparticle (Nano-Se) is a new type of selenium supplement, which can improve the deficiency of traditional selenium supplements and maintain its physiological activity. Due to industrial pollution and irrational use in agriculture, Cu overexposure often occurs in animals and humans. In this study, Nano-Se alleviated CuSO4-induced testicular Cu accumulation, serum testosterone level decrease, testicular structural damage, and decrease in sperm quality. Meanwhile, Nano-Se reduced the ROS content in mice testis and enhanced the activities of T-AOC, GSH, SOD, and CAT compared with CuSO4 group. Furthermore, Nano-Se alleviated CuSO4-induced apoptosis by increasing the protein expression of Cleaved-Caspase-3, Cleaved-Caspase-9, Cleaved-Caspase-12, and Bax/Bcl-2 compared with CuSO4 group. At the same time, Nano-Se reversed CuSO4-induced increase of γ-H2AX protein expression in mice testis. In conclusion, this study confirmed that Nano-Se could alleviate oxidative stress, apoptosis, and DNA damage in the testis of mice with Cu excess, thereby protecting the spermatogenesis disorder induced by Cu.

Multi-omics reveals that alkaline mineral water improves the respiratory health and growth performance of transported calves.

BACKGROUND: Long-distance transportation, a frequent practice in the cattle industry, stresses calves and results in morbidity, mortality, and growth suppression, leading to welfare concerns and economic losses. Alkaline mineral water (AMW) is an electrolyte additive containing multiple mineral elements and shows stress-mitigating effects on humans and bovines. RESULTS: Here, we monitored the respiratory health status and growth performance of 60 Simmental calves subjected to 30 hours of road transportation using a clinical scoring system. Within the three days of commingling before the transportation and 30 days after the transportation, calves in the AMW group (n = 30) were supplied with AMW, while calves in the Control group (n = 29) were not. On three specific days, namely the day before transportation (day -3), the 30th day (day 30), and the 60th day (day 60) after transportation, sets of venous blood, serum, and nasopharyngeal swab samples were collected from 20 calves (10 from each group) for routine blood testing, whole blood transcriptomic sequencing, serology detection, serum untargeted metabolic sequencing, and 16S rRNA gene sequencing. The field data showed that calves in the AMW group displayed lower rectal temperatures (38.967 ℃ vs. 39.022 ℃; p = 0.004), respiratory scores (0.079 vs. 0.144; p < 0.001), appetite scores (0.024 vs. 0.055; p < 0.001), ocular and ear scores (0.185 vs. 0.338; p < 0.001), nasal discharge scores (0.143 vs. 0.241; p < 0.001), and higher body weight gains (30.870 kg vs. 7.552 kg; p < 0.001). The outcomes of laboratory and high throughput sequencing data revealed that the calves in the AMW group demonstrated higher cellular and humoral immunities, antioxidant capacities, lower inflammatory levels, and intestinal absorption and lipogenesis on days -3 and 60. The nasopharynx 16S rRNA gene microbiome analysis revealed the different composition and structure of the nasopharyngeal microflora in the two groups of calves on day 30. Joint analysis of multi-omics revealed that on days -3 and 30, bile secretion was a shared pathway enriched by differentially expressed genes and metabolites, and there were strong correlations between the differentially expressed metabolites and the main genera in the nasopharynx. CONCLUSIONS: These results suggest that AMW supplementation enhances peripheral immunity, nutrition absorption, and metabolic processes, subsequently affecting the nasopharyngeal microbiota and improving the respiratory health and growth performance of transported calves. This investigation provided a practical approach to mitigate transportation stress and explored its underlying mechanisms, which are beneficial for the development of the livestock industry. Video Abstract.

Effects of meloxicam on the welfare of Holstein calves from 6 weeks to 6 months old undergoing amputation dehorning.

Amputation dehorning (AD) is a common practice performed on calves, causing harmful effects such as pain, distress, anxiety, and fear. These effects extend to behavioral, physiological, and hematological responses, prompting serious ethical concerns regarding animal welfare, even when performed with local anesthesia. Meloxicam, a nonsteroidal anti-inflammatory drug, has been widely used to mitigate the side effects of dehorning and disbudding in calves. However, there is a notable gap in research regarding the effects of meloxicam on calves aged 6 wk to 6 mo undergoing AD procedures. This study was designed to assess the effectiveness of co-administering meloxicam with lidocaine, a cornual nerve anesthetic, in alleviating the adverse effects caused by the AD procedure in calves within this age range, compared with the use of lidocaine alone. Thirty Holstein calves were enrolled and randomly divided into 2 groups. The first group received a subcutaneous injection of 5 mL of lidocaine in the horn area and a subcutaneous injection of 0.9% saline at a dose of 0.025 mL/kg in the neck, administered 10 min before the AD procedure. The second group received a combination of lidocaine and meloxicam: a subcutaneous injection of 5 mL of lidocaine in the horn area and a subcutaneous injection of 20 mg/mL meloxicam at a dose of 0.025 mL/kg in the neck, also administered 10 min before the AD procedure. To avoid subjective bias, the researchers were blinded to the treatment groups. Pain-related behaviors, including tail flicking, head shaking, ear flicking, head rubbing, head crossing bar, and kicking, were observed, and physiological parameters, including heart rate, rectal temperature, respiration rate, mechanical nociceptive threshold (MNT), daily active steps, and food intake were monitored. Hematological conditions were determined using enzyme-linked immunosorbent assays and routine blood tests. The data were processed using a generalized linear mixed model. The outcomes demonstrated that the AD procedure increased the frequencies of ear flicking and resulted in rises in the respiration rate, heart rate, rectal temperature, and daily active steps. It also led to decreases in total food intake, forage intake, hay intake, MNT, and increased concentrations of prostaglandin E2 (PgE2), IL-1ß, tumor necrosis factor-α (TNF-α), nitric oxide (NO), and malondialdehyde, as well as glutathione peroxidase activity. However, calves that received meloxicam treatment showed significant improvements in response to the AD procedure, including lower respiration rates, heart rates, and rectal temperatures; higher MNT; and lower intermediate cell ratio. They also had higher red blood counts, hemoglobin levels, hematocrit values; larger mean platelet volumes; and lower concentrations of PgE2, IL-1ß, TNF-α, and NO. These results suggest that co-administration of lidocaine and meloxicam may aid in mitigating the adverse effects induced by the AD procedure on these calves, thereby supporting the use of meloxicam in conjunction with a local anesthetic in AD procedures for calves aged 6 wk to 6 mo.

Copper Promotes LPS-Induced Inflammation via the NF-кB Pathway in Bovine Macrophages.

Inflammation is a complex physiological process that enables the clearance of pathogens and repairing damaged tissues. Elevated serum copper concentration has been reported in cases of inflammation, but the role of copper in inflammatory responses remains unclear. This study used bovine macrophages to establish lipopolysaccharide (LPS)-induced inflammation model. There were five groups in the study: a group treated with LPS (100 ng/ml), a group treated with either copper chelator (tetrathiomolybdate, TTM) (20 µmol) or CuSO4 (25 µmol or 50 µmol) after LPS stimulation, and a control group. Copper concentrations increased in macrophages after the LPS treatment. TTM decreased mRNA expression of pro-inflammatory factors (IL-1ß, TNF-α, IL-6, iNOS, and COX-2), whereas copper supplement increased them. Compared to the control group, TLP4 and MyD88 protein levels were increased in the TTM and copper groups. However, TTM treatment decreased p-p65 and increased IкB-α while the copper supplement showed reversed results. In addition, the phagocytosis and migration of bovine macrophages decreased in the TTM treatment group while increased in the copper treatment groups. Results mentioned above indicated that copper could promote the LPS-induced inflammatory response in bovine macrophages, promote pro-inflammatory factors by activating the NF-кB pathway, and increase phagocytosis capacity and migration. Our study provides a possible targeted therapy for bovine inflammation.

Effects of CuSO4 on hepatic mitochondrial function, biogenesis and dynamics in mice.

Copper is an essential trace element for animal. Excessive intake of copper will cause a large accumulation of copper in the body, especially in the liver, and induce hepatotoxicity, however, there are few studies on the effects of copper on hepatic mitochondrial biogenesis and mitochondrial dynamics. In this study, mice were treated with different doses of CuSO4 (0, 10, 20, and 40 mg/kg) for 21 and 42 days by gavage. The results verified that CuSO4 decreased the content of mitochondrial respiratory chain complexes I-IV in mouse liver. CuSO4 treatment resulted the decrease in the protein and mRNA expression levels of PGC-1α, TFAM, and NRF1, which were the mitochondrial biogenesis regulator proteins. Meanwhile, the proteins involved in mitochondrial fusion were reduced by CuSO4 , such as Mfn1 and Mfn2, however, mitochondrial fission proteins Drip1 and Fis1 were significantly increased. Abovementioned results show that CuSO4 could induce mitochondria damage in the liver of mice, and mitochondrial biogenesis and mitochondrial dynamics are involved in the molecular mechanism of CuSO4 -induced hepatotoxicity.

Metabolome and Transcriptome Combinatory Profiling Reveals Fluconazole Resistance Mechanisms of Trichosporon asahii and the Role of Farnesol in Fluconazole Tolerance.

Trichosporon asahii is a basidiomycete yeast that is pathogenic to humans and animals, and fluconazole-resistant strains have recently increased. Farnesol secreted by fungi is a factor that causes variations in fluconazole resistance; however, few studies have explored the underlying mechanisms. Therefore, this study aims to delineate the fluconazole resistance mechanisms of T. asahii and explore farnesol's effects on these processes. A comparative metabolome-transcriptome analysis of untreated fluconazole-sensitive (YAN), fluconazole-resistant (PB) T. asahii strains, and 25 µM farnesol-treated strains (YAN-25 and PB-25, respectively) was performed. The membrane lipid-related genes and metabolites were upregulated in the PB vs. YAN and PB-25 vs. PB comparisons. Farnesol demonstrated strain-dependent mechanisms underlying fluconazole tolerance between the YAN and PB strains, and upregulated and downregulated efflux pumps in PB-25 and YAN-25 strains, respectively. Membrane lipid-related metabolites were highly correlated with transporter-coding genes. Fluconazole resistance in T. asahii was induced by membrane lipid bio-synthesis activation. Farnesol inhibited fluconazole resistance in the sensitive strain, but enhanced resistance in the resistant strain by upregulating efflux pump genes and membrane lipids. This study offers valuable insights into the mechanisms underlying fungal drug resistance and provides guidance for future research aimed at developing more potent antifungal drugs for clinical use.

Apoptosis and DNA damage mediated by ROS involved in male reproductive toxicity in mice induced by Nickel.

Nickel (Ni) is the most important environmental pollution in the world. Ni has been confirmed to have multi-organ toxicology and carcinogenicity. Recently, Ni also can impair the male reproductive system, however, its precious mechanism still has not been clarified. The current work found that nickel chloride (NiCl2) induced histopathological lesions in testis. And, the Johnsen's score, seminiferous tubule diameter, and spermatogenic epithelium thickness were decreased in NiCl2-treated mice. The number of spermatogonium, primary spermatocyte, and round spermatid also were significantly reduced after Ni treatment. Next the potential molecular mechanism was measured. NiCl2 treatment elevated ROS production in the testis. Additionally, NiCl2 was found to induce apoptosis with features including up-regulation of Bax, cleaved-caspase-3, cleaved-caspase-8, caspase-9, and caspase-12, while down-regulation of Bcl-2 expression. In the meantime, the marker protein of DNA damage γ-H2AX was significantly increased in NiCl2-primed mice testis. To clarify effects of reactive oxygen species (ROS) in apoptosis and DNA damage induced by NiCl2, NiCl2 was used to co-treat antioxidant NAC (N-Acetyl-L-cysteine). NAC weakened ROS production induced by NiCl2, and played an inhibition role in apoptosis and DNA damage. Moreover, co-treatment using NiCl2 and NAC group also eliminated spermatogenesis disorders. In summary, research results reveal the relations of spermatogenesis disorder induced by NiCl2 with apoptosis and DNA damage mediated by ROS and apoptosis in the testis.

Nickel induces blood-testis barrier damage through ROS-mediated p38 MAPK pathways in mice.

Nickel (Ni) is an essential common environmental contaminant, it is hazardous to male reproduction, but the precise mechanisms are still unknown. Blood-testis barrier (BTB), an important testicular structure consisting of connections between sertoli cells, is the target of reproductive toxicity caused by many environmental toxins. In this study, ultrastructure observation and BTB integrity assay results indicated that NiCl2 induced BTB damage. Meanwhile, BTB-related proteins including the tight junction (TJ), adhesion junction (AJ) and the gap junction (GJ) protein expression in mouse testes as well as in sertoli cells (TM4) were significantly decreased after NiCl2 treatment. Next, the antioxidant N-acetylcysteine (NAC) was co-treated with NiCl2 to study the function of oxidative stress in NiCl2-mediated BTB deterioration. The results showed that NAC attenuated testicular histopathological damage, and the expression of BTB-related proteins were markedly reversed by NAC co-treatment in vitro and vivo. Otherwise, NiCl2 activated the p38 MAPK signaling pathway. And, NAC co-treatment could significantly inhibit p38 activation induced by NiCl2 in TM4 cells. Furthermore, in order to confirm the role of the p38 MAPK signaling pathway in NiCl2-induced BTB impairment, a p38 inhibitor (SB203580) was co-treated with NiCl2 in TM4 cells, and p38 MAPK signaling inhibition significantly restored BTB damage induced by NiCl2 in TM4 cells. These results suggest that NiCl2 treatment destroys the BTB, in which the oxidative stress-mediated p38 MAPK signaling pathway plays a vital role.

A Clinical Trial on the Welfare Effects of Administering Meloxicam to 10 to 21 Day Dairy Calves Following Caustic Paste Disbudding.

Caustic paste disbudding (CPD) is widely utilized for calves, which has been known to result in adverse effects on the calves and ethical concerns related to animal welfare, despite the use of local anesthetics. The administration of meloxicam has been demonstrated to provide benefits in alleviating pain and inflammation in juvenile calves under 9 d old and subjected to CPD. Nonetheless, there is a scarcity of literature documenting the beneficial impact of meloxicam in alleviating pain in calves aged over 9 d that have undergone CPD. Therefore, the objective of this clinical trial was to evaluate the efficacy of administering meloxicam and lidocaine for cornual nerve block together in mitigating the deleterious effects of CPD, as opposed to using lidocaine alone in calves older than 9 d. Thirty Holstein calves, aged between 10 and 21 d, were enrolled and randomly assigned to 1 of 2 treatments: lidocaine alone (Placebo), lidocaine and normal saline treatment before CPD, and lidocaine plus meloxicam, lidocaine and 0.5 mg/kg of meloxicam treatment prior to CPD. The researchers were blind to the treatment of calves to control the subjective error. The occurrences of actions associated with pain, which included head shaking, head rubbing, ear flicking, tail flicking, kicking, and head passing through the fence, were recorded. Physiological performance, including the respiration rate, heart rate, rectal temperature, mechanical nociceptive threshold (MNT), food intake, and daily activity level, was monitored. Hematological conditions were ascertained through the use of routine blood tests and enzyme-linked immunosorbent assay. The generalized linear mixed model was employed to analyze the data. The research findings revealed that applying the CPD procedure significantly elevated the frequencies of tail flicking, head shaking, and kicking, resulted in increases in respiratory rate, heart rate, daily active steps, and food intake and a decrease in MNT, and led to alterations in hematological markers, including platelet counts, mean platelet volume, prostaglandin E2, constitutive nitric oxide synthase, and hydroxyl radical. Considerable benefits, such as lower heart rates, higher food intake, and MNTs, as well as lower levels of white blood cell counts, lymphocyte counts, hemoglobin, mean platelet volume, prostaglandin E2, tumor necrosis factor-α, constitutive nitric oxide synthase, malondialdehyde, and hydroxyl radical, were observed in the calves that received meloxicam treatment in response to CPD. The findings of the study indicate that the co-administration of lidocaine and meloxicam provides obvious benefits in mitigating pain, inflammation, and oxidative stress in calves aged over 9 d and undergoing CPD. This endorses the use of meloxicam during the disbudding and dehorning procedures of calves.

Caustic paste disbudding (CPD) is a widely used practice in the cattle industry, yet there is a shortage of literature on the effects of meloxicam on calves aged 10 to 21 d who have undergone this procedure. In this clinical trial, we conducted a comparative analysis of the pain-related behavioral, physiological, and hematological performance of calves that were administered with either lidocaine plus normal saline (n = 15) or lidocaine plus meloxicam (n = 15) before undergoing disbudding operations. The findings demonstrated that the CPD operation had a significant impact on the pain-related behavior, physiological functions, and serum anti-inflammatory and antioxidative markers of the calves. On the other hand, the administration of meloxicam had notable advantages for the calves by enhancing the physiological and hematological parameters.

Low Glucose plus ß-Hydroxybutyrate Induces an Enhanced Inflammatory Response in Yak Alveolar Macrophages via Activating the GPR109A/NF-κB Signaling Pathway.

Yaks are often subject to long-term starvation and a high prevalence of respiratory diseases and mortality in the withered season, yet the mechanisms that cause this remain unclear. Research has demonstrated that ß-hydroxybutyrate (BHB) plays a significant role in regulating the immune system. Hence, we hypothesize that the low glucose and high BHB condition induced by severe starvation might have an effect on the pro-inflammatory response of the alveolar macrophages (AMs) in yaks. To validate our hypothesis, we isolated and identified primary AMs from freshly slaughtered yaks and cultured them in a medium with 5.5 mM of glucose or 2.8 mM of glucose plus 1-4 mM of BHB. Utilizing a real-time quantitative polymerase chain reaction (RT-qPCR), immunoblot assay, and enzyme-linked immunosorbent assay (ELISA), we evaluated the gene and protein expression levels of GPR109A (G-protein-coupled receptor 109A), NF-κB p65, p38, and PPARγ and the concentrations of pro-inflammatory cytokines interleukin (IL)-1ß and IL-6 and tumor necrosis factor (TNF)-α in the supernatant. The results demonstrated that AMs exposed to low glucose plus BHB had significantly higher levels of IL-1ß, IL-6, and TNF-α (p < 0.05) and higher activity of the GPR109A/NF-κB signaling pathway. A pretreatment of either pertussis toxin (PTX, inhibitor of GPR109A) or pyrrolidinedithiocarbamic (PDTC, inhibitor of NF-κB p65) was effective in preventing the elevated secretion of pro-inflammatory cytokines induced by low glucose plus BHB (p < 0.05). These results indicated that the low glucose plus BHB condition would induce an enhanced pro-inflammatory response through the activation of the GPR109A/NF-κB signaling pathway in primary yak AMs, which is probably the reason why yaks experience a higher rate of respiratory diseases and mortality. This study will offer new insight into the prevention and treatment of bovine respiratory diseases.

Unraveling extracellular protein signatures to enhance live attenuated vaccine development through type II secretion system disruption in Vibriomimicus.

Type II secretion systems (T2SS) are important molecular machines used by bacteria to transport a wide range of proteins across the outer membrane from the periplasm. Vibrio mimicus is an epidemic pathogen threats to both aquatic animals and human health. Our previous study demonstrates that T2SS deletion reduced virulence by 307.26 times in yellow catfish. However, the specific effects of T2SS-mediated extracellular protein secretion in V. mimicus, including its potential role in exotoxin secretion or other mechanisms, require further investigation. Through proteomics and phenotypic analyses, this study observed that the ΔT2SS strain exhibited significant self-aggregation and dynamic deficiency, with a notable negative correlation with subsequent biofilm formation. The proteomics analysis revealed 239 different abundances of extracellular proteins after T2SS deletion, including 19 proteins with higher abundance and 220 proteins with lower and even absent in the ΔT2SS strain. These extracellular proteins are involved in various pathways, such as metabolism, virulence factors expression, and enzymes. Among them, purine, pyruvate, and pyrimidine metabolism, and the Citrate cycle, were the primary pathways affected by T2SS. Our phenotypic analysis is consistent with these findings, suggesting that the decreased virulence of ΔT2SS strains is due to the effect of T2SS on these proteins, which negatively impacts growth, biofilm formation, auto-aggregation, and motility of V. mimicus. These results provide valuable insights for designing deletion targets for attenuated vaccines development against V. mimicus and expand our understanding of the biological functions of T2SS.

Integrated bioinformatics identifies key mediators in cytokine storm and tissue remodeling during Vibrio mimicus infection in yellow catfish (Pelteobagrus fulvidraco).

Introduction: The pathogenesis of Vibrio mimicus infection in yellow catfish (Pelteobagrus fulvidraco) remains poorly understood, particularly regarding the impact of infection with the pathogen on primary target organs such as the skin and muscle. Methods: In this study, we aim to analyze the pathological intricacies of the skin and muscle of yellow catfish after being infected with V. mimicus using a 1/10 LC50 seven-day post-infection model. Furthermore, we have utilized integrated bioinformatics to comprehensively elucidate the regulatory mechanisms and identify the key regulatory genes implicated in this phenomenon. Results: Our histopathological examination revealed significant pathological changes in the skin and muscle, characterized by necrosis and inflammation. Moreover, tissue remodeling occurred, with perimysium degeneration and lesion invasion into the muscle along the endomysium, accompanied by a transformation of type I collagen into a mixture of type I and type III collagens in the perimysium and muscle bundles. Our eukaryotic transcriptomic and 4D label-free analyses demonstrated a predominantly immune pathway response in both the skin and muscle, with downregulation observed in several cell signaling pathways that focused on focal adhesion-dominated cell signaling pathways. The upregulated genes included interleukins (IL)-1 and -6, chemokines, and matrix metallopeptidases (mmp)-9 and -13, while several genes were significantly downregulated, including col1a and col1a1a. Further analysis revealed that these pathways were differentially regulated, with mmp-9 and mmp-13 acting as the potential core regulators of cytokine and tissue remodeling pathways. Upregulation of NF-κB1 and FOSL-1 induced by IL-17C and Nox 1/2-based NADPH oxidase may have held matrix metallopeptidase and cytokine-related genes. Also, we confirmed these relevant regulatory pathways by qPCR and ELISA in expanded samples. Discussion: Our findings unequivocally illustrate the occurrence of a cytokine storm and tissue remodeling, mediated by interleukins, chemokines, and MMPs, in the surface of yellow catfish infected with V. mimicus. Additionally, we unveil the potential bidirectional regulatory role of MMP-9 and MMP-13. These results provide novel perspectives on the intricate immune response to V. mimicus infection in yellow catfish and highlight potential targets for developing therapies.

Autophagy-mediated ferroptosis involved in nickel-induced nephrotoxicity in the mice.

Nickel, as a widely polluted metal, has been shown nephrotoxicity. Ferroptosis is a new type of cell death driven by iron-dependent lipid peroxidation. Our study found that nickel chloride (NiCl2) induced ferroptosis in mouse kidney and TCMK-1 cells. The iron content was significantly increased in the kidney and TCMK-1 cells after NiCl2 treatment. Lipid peroxidation and MDA content were significantly increased, and GSH content and T-SOD activity were significantly decreased after exposure to NiCl2. Moreover, NiCl2 increased COX-2 protein levels, decreased SLC7A11 and GPX4 protein levels, and elevated Ptgs2 mRNA levels. Next, the mechanism of Ni-induced ferroptosis was investigated. The results showed that NiCl2 induced autophagy in TCMK-1 cells, which promoted ferroptosis induced by NiCl2. Furthermore, the data of autophagy activation or inhibition experiment showed that autophagy facilitated ferroptosis through the degradation of the iron regulation protein NCOA4 and FTH1. Otherwise, iron chelator DFOM treatment inhibited ferroptosis induced by NiCl2. Finally, ferroptosis inhibitor Fer-1 treatment significantly alleviated cytotoxicity induced by NiCl2. To sum up, our above results showed that ferroptosis is involved in NiCl2-induced nephrotoxicity, and NiCl2 induces autophagy-dependent ferritin degradation, releases iron ions, leads to iron overload, and induces ferroptosis. This study supplies a new theoretical foundation for the study of nickel and renal toxicity.

RAGE-TLR4 Crosstalk Is the Key Mechanism by Which High Glucose Enhances the Lipopolysaccharide-Induced Inflammatory Response in Primary Bovine Alveolar Macrophages.

The receptor of advanced glycation end products (RAGE) and Toll-like receptor 4 (TLR4) are important receptors for inflammatory responses induced by high glucose (HG) and lipopolysaccharide (LPS) and show crosstalk phenomena in inflammatory responses. However, it is unknown whether RAGE and TLR4 can influence each other's expression through a crosstalk mechanism and whether the RAGE-TLR4 crosstalk related to the molecular mechanism of HG enhances the LPS-induced inflammatory response. In this study, the implications of LPS with multiple concentrations (0, 1, 5, and 10 µg/mL) at various treatment times (0, 3, 6, 12, and 24 h) in primary bovine alveolar macrophages (BAMs) were explored. The results showed that a 5 µg/mL LPS treatment at 12 h had the most significant increment on the pro-inflammatory cytokine interleukin 1ß (IL-1ß), IL-6, and tumor necrosis factor (TNF)-α levels in BAMs (p < 0.05) and that the levels of TLR4, RAGE, MyD88, and NF-κB p65 mRNA and protein expression were upregulated (p < 0.05). Then, the effect of LPS (5 µg/mL) and HG (25.5 mM) co-treatment in BAMs was explored. The results further showed that HG significantly enhanced the release of IL-1ß, IL-6, and TNF-α caused by LPS in the supernatant (p < 0.01) and significantly increased the levels of RAGE, TLR4, MyD88, and NF-κB p65 mRNA and protein expression (p < 0.01). Pretreatment with FPS-ZM1 and TAK-242, the inhibitors of RAGE and TLR4, significantly alleviated the HG + LPS-induced increment of RAGE, TLR4, MyD88, and NF-κB p65 mRNA and protein expression in the presence of HG and LPS (p < 0.01). This study showed that RAGE and TLR4 affect each other's expression through crosstalk during the combined usage of HG and LPS and synergistically activate the MyD88/NF-κB signaling pathway to promote the release of pro-inflammatory cytokines in BAMs.

Nickel induces hepatotoxicity by mitochondrial biogenesis, mitochondrial dynamics, and mitophagy dysfunction.

Nickel (Ni) is an important and widely hazardous chemical industrial waste. Excessive Ni exposure could cause multi-organs toxicity in human and animals. Liver is the major target organ of Ni accumulation and toxicity, however, the precise mechanism is still unclear. In this study, nickel chloride (NiCl2 )-treatment induced hepatic histopathological changes in the mice, and, transmission electron microscopy results showed mitochondrial swollen and deformed of hepatocyte. Next, the mitochondrial damages including mitochondrial biogenesis, mitochondrial dynamics, and mitophagy were measured after NiCl2 administration. The results showed that NiCl2 suppressed mitochondrial biogenesis by decreasing PGC-1α, TFAM, and NRF1 protein and mRNA expression levels. Meanwhile, the proteins involved in mitochondrial fusion were reduced by NiCl2 , such as Mfn1 and Mfn2, however, mitochondrial fission proteins Drip1 and Fis1 were significantly increased. The up-regulation of mitochondrial p62 and LC3II expression indicated that NiCl2 increased mitophagy in the liver. Moreover, the receptor-mediated mitophagy and ubiquitin (Ub)-dependent mitophagy were detected. NiCl2 promoted PINK1 accumulation and Parkin recruitment on mitochondria. And, the receptor proteins of mitophagy Bnip3 and FUNDC1 were increased in the NiCl2 -treated mice liver. Overall, these results show that NiCl2 could induce mitochondria damage in the liver of mice, and, dysfunction of mitochondrial biogenesis, mitochondrial dynamics and mitophagy involved in the molecular mechanism of NiCl2 -induced hepatotoxicity.