Modulation of apoptosis and Inflammasome activation in chondrocytes: co-regulatory role of Chlorogenic acid.

BACKGROUND: The B-cell lymphoma 2 (Bcl-2) protein regulates programmed cell death throughout the disease conditions by upholding apoptotic pathways. However, the mechanism by which it's expressed in chondrocytes still needs to be studied in chondrocyte-related disorders. Additionally, exploring the potential therapeutic role of Chlorogenic acid (CGA) in confluence with Bcl-2 modulation is of significant interest. METHODS: In vivo and in vitro studies were performed according to our previous methodologies. The chondrocytes were cultured in specific growth media under standard conditions after expression verification of different microRNAs through high-throughput sequencing and verification of Bcl-2 involvement in tibial growth plates. The effect of Bcl-2 expression was investigated by transfecting chondrocytes with miR-460a, siRNA, and their negative controls alone or in combination with CGA. The RNA was extracted and subjected to a reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Western blot analysis and immunofluorescence assays were performed to visualize the intracellular localization of Bcl-2 and associated proteins related to apoptotic and inflammasome pathways. Moreover, apoptosis through flow cytometry was also performed to understand the modulation of concerning pathways. RESULTS: The suppression of Bcl-2 induced higher apoptosis and mitochondrial dysfunction, leading to IL-1ß maturation and affecting the inflammasome during chondrocyte proliferation. Conversely, overexpression attenuated the activation, as evidenced by reduced caspase activity and IL-1ß maturation. In parallel, CGA successfully reduced siRNA-induced apoptosis by decreasing Cytochrome C (Cyto C) release from the mitochondria to the cytoplasm, which in turn decreased Caspase-3 and Caspase-7 cleavage with Bcl-2-associated X protein (Bax). Furthermore, siBcl-2 transfection and CGA therapy increased chondrocyte proliferation and survival. The CGA also showed a promising approach to maintaining chondrocyte viability by inhibiting siRNA-induced apoptosis. CONCLUSIONS: Targeting Bcl-2-mediated regulation might be a possible treatment for chondrocyte-related conditions. Moreover, these results add knowledge of the complicated processes underlying chondrocyte function and the pathophysiology of related diseases, highlighting the significance of target specific therapies. Video Abstract.

Decoding molecular signature on heart of septic mice with distinct left ventricular ejection fraction.

Dysregulated cardiac function after sepsis in intensive care unit is known to predict poor long-term outcome and increase mortality. Their pathological feature and molecular mechanism remain unclear. We observed that septic patients with depressed left ventricular ejection fraction (LVEF) have the highest in-hospital and 28 days mortality comparing to patients with hyperdynamic LVEF or with heart failure with preserved LVEF. Echocardiograms reveal that survivors post cecum ligation and puncture (CLP) on rodents have stable LVEF and non-survivors have fluctuated LVEF at CLP early phase. CLP-induced mice fall into three groups based on LVEF 24 h post-surgery: high-, low-, and normal-LVEF. Transcriptomic and proteomic analyses identify jointly and distinctively changed genes, proteins and biologically essential pathways in left ventricles from three CLP groups. Notably, transmission electron microscopy shows different mitochondrial and sarcomere defects associated with LVEF variances. Together, this study systematically characterizes the molecular, morphological, and functional alterations in CLP-induced cardiac injury.

Development of a nomogram model for the early prediction of sepsis-associated acute kidney injury in critically ill patients.

Sepsis-associated acute kidney injury is a common complication of sepsis, but it is difficult to predict sepsis-associated acute kidney injury. In this retrospective observational study, adult septic patients were recruited from the MIMIC-III database as the training cohort (n = 4764) and from Xiangya Hospital (n = 1568) and Zhang's database as validation cohorts. We identified eleven predictors with seven independent risk predictors of sepsis-associated acute kidney injury [fluid input_day1 ≥ 3390 ml (HR hazard ratio 1.42), fluid input_day2 ≥ 2734 ml (HR 1.64), platelet_min_day5 ≤ 224.2 × 109/l (HR 0.86), length of ICU stay ≥ 2.5 days (HR 1.24), length of hospital stay ≥ 5.8 days (HR 1.18), Bun_max_day1 ≥ 20 mmol/l (HR 1.20), and mechanical ventilation time ≥ 96 h (HR 1.11)] by multivariate Cox regression analysis, and the eleven predictors were entered into the nomogram. The nomogram model showed a discriminative ability for estimating sepsis-associated acute kidney injury. These results indicated that clinical parameters such as excess input fluid on the first and second days after admission and longer mechanical ventilation time could increase the risk of developing sepsis-associated acute kidney injury. With our study, we built a real-time prediction model for potentially forecasting acute kidney injury in septic patients that can help clinicians make decisions as early as possible to avoid sepsis-associated acute kidney injury.

Ferroptosis-mediated immune responses in cancer.

Cell death is a universal biological process in almost every physiological and pathological condition, including development, degeneration, inflammation, and cancer. In addition to apoptosis, increasing numbers of cell death types have been discovered in recent years. The biological significance of cell death has long been a subject of interest and exploration and meaningful discoveries continue to be made. Ferroptosis is a newfound form of programmed cell death and has been implicated intensively in various pathological conditions and cancer therapy. A few studies show that ferroptosis has the direct capacity to kill cancer cells and has a potential antitumor effect. As the rising role of immune cells function in the tumor microenvironment (TME), ferroptosis may have additional impact on the immune cells, though this remains unclear. In this study we focus on the ferroptosis molecular network and the ferroptosis-mediated immune response, mainly in the TME, and put forward novel insights and directions for cancer research in the near future.

Epigallocatechin Gallate and Glutathione Attenuate Aflatoxin B1-Induced Acute Liver Injury in Ducklings via Mitochondria-Mediated Apoptosis and the Nrf2 Signalling Pathway.

Aflatoxin B1 (AFB1) exists widely in feed and food with severe hazards, posing a serious threat to human and animal health. Epigallocatechin gallate (EGCG) and glutathione (GSH) have been reported as having anti-oxidative and other functions. The present study aimed to investigate the detoxification effect of EGCG and GSH alone or in combination on AFB1 exposure in ducklings. Fifty one-day-old male ducklings were randomly assigned into five experimental groups (n = 10): 1. Control (CTR); 2. 0.3 mg/kg BW AFB1 (AFB1); 3. 0.3 mg/kg BW AFB1 + 100 mg/kg BW EGCG (AFB1 + EGCG); 4. 0.3 mg/kg BW AFB1 + 30 mg/kg BW GSH (AFB1 + GSH); 5. 0.3 mg/kg BW AFB1 + 100 mg/kg BW EGCG + 30 mg/kg BW GSH (AFB1 + EGCG + GSH). The experiment lasted for seven days. Compared with the CTR group, AFB1 reduced growth performance, total serum protein and albumin content, increased serum enzyme activity (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyl transpeptidase), and caused pathological damage to the ducklings' livers. AFB1 exposure increased malondialdehyde content and decreased superoxide dismutase, total antioxidant capacity, catalase, glutathione peroxidase activities, and glutathione content in the liver. EGCG and GSH alone or in combination mitigated these adverse effects. Meanwhile, EGCG and GSH attenuate apoptosis of hepatocytes, and regulated AFB1-induced changes in the abundance of genes contained in the Keap1/Nrf2 signalling and apoptotic pathways. Collectively, these results suggest that EGCG and GSH alleviate the hepatocyte injury induced by AFB1 by inhibiting oxidative stress and attenuating excessive mitochondria-mediated apoptosis.

Effects of Zearalenone on Production Performance, Egg Quality, Ovarian Function and Gut Microbiota of Laying Hens.

Zearalenone (ZEN) is a ubiquitous contaminant in poultry feed, since ZEN and its metabolites can interfere with estrogen function and affect the reproductive ability of animals. The estrogen-like effect of ZEN on mammal is widely reported, while little information is available, regarding the effect of relatively low dose of ZEN on estrogen function and production performance of laying hens, and the relationship between them. This work was aimed to investigate the effects of ZEN on the production performance, egg quality, ovarian function and gut microbiota of laying hens. A total of 96 Hy-line brown laying hens aged 25-week were randomly divided into 3 groups including basal diet group (BD group), basal diet supplemented with 250 µg/kg (250 µg/kg ZEN group) and 750 µg/kg (750 µg/kg ZEN group) ZEN group. Here, 750 µg/kg ZEN resulted in a significant increase in the feed conversion ratio (FCR) (g feed/g egg) (p < 0.05), a decrease in the egg production (p > 0.05), albumen height and Haugh unit (p > 0.05), compared to the BD group. The serum Follicle-stimulating hormone (FSH) levels significantly decreased in ZEN supplemented groups (p < 0.05). Serum Luteinizing hormone (LH) and Progesterone (P) levels in the 750 µg/kg ZEN group were significantly lower than those in the BD group (p < 0.05). 16S rRNA sequencing indicated that ZEN reduced cecum microbial diversity (p < 0.05) and altered gut microbiota composition. In contrast to 250 µg/kg ZEN, 750 µg/kg ZEN had more dramatic effects on the gut microbiota function. Spearman's correlation analysis revealed negative correlations between the dominant bacteria of the 750 µg/kg ZEN group and the production performance, egg quality and ovarian function of hens. Overall, ZEN was shown to exert a detrimental effect on production performance, egg quality and ovarian function of laying hens in this study. Moreover, alterations in the composition and function of the gut microbiota induced by ZEN may be involved in the adverse effects of ZEN on laying hens.

Application of Porous Polyetheretherketone Scaffold/Vancomycin-Loaded Thermosensitive Hydrogel Composites for Antibacterial Therapy in Bone Repair.

Polyetheretherketone (PEEK) has been widely used in bone repair, but it often fails due to bacterial infection. Herein, a high-strength porous polyetheretherketone scaffold (ps-PK) loaded with antibacterial drug-loaded hydrogel strategy is proposed. The prepared ps-PK possesses high porosity (30.8-64.7%) and the compression modulus is between 0.4 and 0.98 GPa. The interconnected pore-type structure endows it with a drug loading capacity. Poly(D,L -lactic acid-co-glycolic acid)-b-Poly(ethylene glycol)-b-Poly(D,L -lactic acid-co-glycolic acid) (PLGA-PEG-PLGA) thermoresponsive hydrogels loaded with vancomycin are used as the drug sustained-release system. The vancomycin-loaded hydrogels in the solution state at a low temperature are filled into a porous polyetheretherketone scaffold (ps-PK-VGel) and formed a gel state after implantation in vivo. The antibacterial rate of ps-PK-VGel against methicillin-resistant staphylococcus aureus in vitro is 99.7% and histological observation in vivo demonstrates that the ps-PK-VGel shows obvious antibacterial activity. Given its excellent antibacterial ability and mechanical properties, the porous PEEK scaffold composite drug-loaded thermosensitive hydrogel has great potential in bone repair surgery applications.

Deoxynivalenol triggers porcine intestinal tight junction disorder through hijacking SLC5A1 and PGC1α-mediated mitochondrial function.

Deoxynivalenol (DON) is a mycotoxin frequently occurring in human and animal food worldwide, which raises increasing public health concerns. Growing evidence suggests that mitochondria is a pivotal molecular target for DON. However, the contribution of mitochondrial dysfunction to the pathogenesis of DON-induced gut epithelial barrier disruption remains poorly understood. In an animal experiment, piglets exposed to 2.89 mg DON/kg feed for 4 weeks showed altered metabolomic profiling in the serum and compromised transcriptome in the jejunum. DON exposure also impaired mitochondrial structure in the jejunal mucosa, corresponding with dysfunction of the tight junctions. In IPEC-J2 cells, metabolomic and transcriptomic analyses revealed that DON exposure perturbed biological processes occurring in the mitochondria and disordered the expression of genes involved in mitochondrial energy metabolism. Fuel utilization from glucose was affected by DON exposure, as were mitochondrial morphological dynamics leading to increased fragmentation. A marked loss of Na+/glucose cotransporter (SLC5A1) and peroxisome proliferator activated receptor-γ co-activator 1α (PGC1α) was observed in DON-treated cells. Taken together, our data highlight the critical role of impaired mitochondrial energy metabolism and mitochondrial biogenesis in abnormal intestinal tight junction upon DON exposure, and provide a potential mitochondrial target for intestinal mucosal restoration following DON exposure.

The Hyperbilirubinemia and Potential Predictors Influence on Long-Term Outcomes in Sepsis: A Population-Based Propensity Score-Matched Study.

Objective: Although hyperbilirubinemia has been associated with mortality in patients who are critically ill, yet no clinical studies dissect the effect of dynamic change of hyperbilirubinemia on long-term septic prognosis. The study aims to investigate the specific stages of hyperbilirubinemia and potential risk factors on long-term outcomes in patients with sepsis. Methods: In this retrospective observational cohort study, patients with sepsis, without previous chronic liver diseases, were identified from the Medical Information Mart for the Intensive Care III MIMIC-III database. We used propensity scores (PS) to adjust the baseline differences in septic patients with hyperbilirubinemia or not. The multivariate Cox was employed to investigate the predictors that influence a clinical outcome in sepsis. Results: Of 2,784 patients with sepsis, hyperbilirubinemia occurred in 544 patients (19.5%). After PS matching, a survival curve demonstrated that patients with sepsis with the new onset of total bilirubin (TBIL) levels more than or equal to 5 mg/dl survived at significantly lower rates than those with TBIL levels <5 mg/dl. Multivariate Cox hazard analysis showed that patients with TBIL at more than or equal to 5 mg/dl during sepsis exhibit 1.608 times (95% CI: 1.228-2.106) higher risk of 1-year mortality than those with TBIL levels <5 mg/dl. Also, age above 65 years old, preexisting malignancy, a respiratory rate above 30 beats/min at admission, serum parameters levels within 24-h admission, containing international normalized ratio (INR) above 1.5, platelet <50*10∧9/L, lactate above 4 mmol/L, and bicarbonate <22 or above 29 mmol/L are the independent risk factors for long-term mortality of patients with sepsis. Conclusions: After PS matching, serum TBIL levels at more than or equal to 5 mg/dl during hospitality are associated with increased long-term mortality for patients with sepsis. This study may provide clinicians with some cutoff values for early intervention, which may improve the prognosis of patients with sepsis.

The insensitive mechanism of poultry to zearalenone: A review.

Zearalenone (ZEN) is one of the most common contaminating mycotoxins and is mainly produced by Fusarium graminearum. ZEN and its metabolites can interfere with estrogen function and affect animals' reproductive ability. Pigs are most susceptible to ZEN, and ZEN is less harmful to poultry than to pigs. The exact mechanism for the difference in susceptibility remains unclear. In this review, we summarized some possible reasons for the relative insensitivity of poultry to ZEN, such as the lower total amount of α-zearalenol (α-ZOL) and the α-ZOL-to-ß-ZOL ratio which reduce the toxicity of ZEN to poultry. The faster hepatic and enteric circulation, and excretion capacity in poultry can excrete more ZEN and its metabolites. There are other possible factors such as the transformation of intestinal microorganisms, differences in hydroxysteroid dehydrogenases' activity, high estrogen levels, and low estrogen receptors affinity which can also cause poultry to be relatively insensitive to ZEN. In this review, we summarized the hazards, pollution status, metabolic pathways, and some measures to mitigate ZEN's harmfulness. Specifically, we discussed the possible mechanisms of low reproductive toxicity by ZEN in poultry.

Effects of Dietary Cottonseed Oil and Cottonseed Meal Supplementation on Liver Lipid Content, Fatty Acid Profile and Hepatic Function in Laying Hens.

Antinutrients, such as cyclopropene fatty acids (CPFAs) and free gossypol (FG), present together in cottonseed have caused numerous adverse effects on liver health and egg quality of laying hens, which are both likely to be related to a disturbance in lipid metabolism. This experiment employed a 3 × 3 factorial arrangement using corn-soybean-meal-based diets supplemented with different levels of cottonseed oil (0%, 2%, or 4% CSO) containing CPFAs and cottonseed meal (0%, 6%, or 12% CSM) containing FG to elucidate the effects of them or their interaction on fatty acid profile, lipid content, and liver health of laying hens. An overall increase in fatty acid saturation and an overall significant decrease (p < 0.05) in monounsaturated fatty acids (MUFAs) were shown in the livers of hens fed diets with either 2% or 4% CSO. Meanwhile, the concentration of liver cholesterol, serum cholesterol, and serum LDL-c of hens fed a diet supplemented with a high level of CSO (4%) were noticeably increased (p < 0.05). Even though the supplementation of 4% CSO in diets aroused beneficial influences on liver function, a high level of CSO inclusion in laying hens' diets is not recommended due to its hypercholesterolemia effect. In conclusion, supplementation of CSO, which contains 0.20% CPFAs, was the primary cause of alteration in fatty acid composition and cholesterol content in hens, while no interaction between CSM and CSO nor CSM effect was found for lipid profile and liver health in laying hen.

Dietary Se deficiency dysregulates metabolic and cell death signaling in aggravating the AFB1 hepatotoxicity of chicks.

The objective of this study was to use isobaric tags for relative and absolute quantitation (iTRAQ) proteomic technology to systematically analyze the hepatotoxic mechanism of aflatoxin B1 (AFB1) and its prevention by Se in broilers. Four groups of day-old broilers were allocated into a 2 × 2 factorial design trial that fed a Se-deficient based diet (BD) or the BD + 1.0 mg AFB1/kg, 0.3 mg Se/kg, or 1.0 mg AFB1/kg plus 0.3 mg Se/kg for 3 wk. Dietary AFB1 increased serum ALT and decreased total protein and albumin concentrations, and induced hepatic histopathological lesions in Se adequate groups. Notably, Se deficiency exacerbated these AFB1-induced changes. Furthermore, Se deficiency reduced hepatic glutathione peroxidase but increased thioredoxin reductase and glutathione S-transferase activities and 8-hydroxydeoxyguanosine concentration in AFB1 administrated groups. Moreover, AFB1 dysregulated 261 co-differentially expressed proteins (DEPs) in both Se adequate and deficiency diets, and Se deficiency dysregulated 64 DEPs in AFB1 administrated diets. These DEPs are mainly related to phase I and II metabolizing enzymes, heat shock proteins, DNA repair, fatty acid metabolism and apoptosis. The in vitro study has verified that aldo-keto reductase family1, member10 plays an important role in AFB1-induced hepatotoxicity and Se-mediated detoxification of AFB1 in a chicken leghorn male hepatoma cells. Conclusively, this study has analyzed the hepatic proteome response to dietary AFB1 and Se, and thus shed new light on the mechanisms of hepatotoxicity of AFB1 and its detoxification by Se in broilers.

Transcriptomics and flow cytometry reveals the cytotoxicity of aflatoxin B1 and aflatoxin M1 in bovine mammary epithelial cells.

Aflatoxin is a known mycotoxin that pollutes various grains widely in the environment. Aflatoxin B1 (AFB1) and Aflatoxin M1 (AFM1) have been shown to induce cytotoxicity in many cells, yet their effects on mammary epithelial cells remain unclear. In this study, we examined the toxicity and the effects of AFB1 and AFM1 on bovine mammary epithelial cells (BME cells). The cells were treated with AFB1 or AFM1 at a concentration of 0-10 mg/L for 24 or 48 h, followed by cytotoxicity assays, flow cytometry, and transcriptomics. Our results demonstrated that AFB1 and AFM1 induced cell proliferation inhibition, apoptosis and cell cycle arrest. However, the level of intracellular reactive oxygen species has no significant difference. The RNA-Seq results also showed that AFB1 and AFM1 changed many related gene expressions like apoptosis and oxidative stress, cycle, junction, and signaling pathway. Taken together, AFB1 and AFM1 were found to affect cytotoxicity and related gene changes in BME cells. Notably, this study reported that 2 mg/L of AFB1 and AFM1 affected the expression of methylation-related genes, and ultimately altered the rate of m6A methylation in RNA. It may provide a potential direction for toxins to indirectly regulate gene expression by affecting RNA methylation modification. Our research provides some novel insights and data about AFB1 and AFM1 toxicity in BME cells.

Effects of dietary cadmium supplementation on production performance, cadmium residue in eggs, and hepatic damage in laying hens.

This study was conducted to investigate the adverse effects of cadmium (Cd) on the production performance, serum biochemistry, liver antioxidant status, histopathology, and egg residue in laying hens. A total of 72 healthy Hy-Line brown laying hens at 40-week-old were randomly assigned to four diets containing 0 (control diet), 15, 30, or 60 mg/kg Cd for 6 weeks. Laying hens exposed to 60 mg/kg Cd had lower egg production rate and worse feed to egg ratio (P < 0.05). Dietary Cd exposure (≥ 15 mg/kg) significantly decreased hepatic glutathione peroxide (GPX) activities, while increasing malondialdehyde (MDA) (P < 0.05). Hepatic histopathology and ultrastructure also showed damage and the symptoms were exacerbated in a dose-dependent manner. The residue of Cd in the yolk was increased with increasing dietary Cd concentration. The mRNA expression levels of mt4L, mt3, sod1, sod2, gpx1, gpx3, and gpx4 in the liver of laying hens exposed to 60 mg Cd/kg feed were significantly decreased (P < 0.05). In conclusion, dietary Cd exposure at ≥ 15 mg/kg induced hepatic damage in laying hens, indicating that the content of Cd in feed must be critically controlled.

The paradoxical effects of progesterone on the eggshell quality of laying hens.

This study demonstrates the effects of progesterone on eggshell quality and ultrastructure by injecting progesterone into laying hens 2 and 5 h post-oviposition, respectively. Progesterone injected 2 h post-oviposition (P4-2 h) improved eggshell quality with a significant decrease (P < 0.01) in the thickness of the mammillary layer and a significant increase (P < 0.01) in the thickness of the effective layer in the eggshell ultrastructure compared to the control. Progesterone injected 5 h post-oviposition (P4-5 h) damaged the eggshell quality by significantly reducing (P < 0.01) the effective layer thickness. Progesterone injected delayed obviously (P < 0.01) the following oviposition. Moreover, the concentrations of Thr, Cys, Leu, Lys, and His in the eggshell membranes were significantly higher (P < 0.05) in the P4-2 h treated hens whereas Val and Lys were significantly lower (P < 0.05) in P4-5 h treated hens compared to the control. Therefore, progesterone shows paradoxical effects on eggshell quality depending on the injection time-points post-oviposition, which could explain the contradictions in previous related reports. P4 injected affected the content of amino acids in eggshell membranes, especially lysine which contributed to eggshell quality. In addition, P4 injected 2 h after oviposition improved eggshell quality by promoting the premature fusion of mammillary knobs. This work contributed to a novel insight to understanding the mechanism of improving eggshell quality.

The effect of dietary supplementation with Clostridium butyricum on the growth performance, immunity, intestinal microbiota and disease resistance of tilapia (Oreochromis niloticus).

This study was conducted to assess the effects of dietary Clostridium butyricum on the growth, immunity, intestinal microbiota and disease resistance of tilapia (Oreochromis niloticus). Three hundreds of tilapia (56.21 ± 0.81 g) were divided into 5 groups and fed a diet supplemented with C. butyricum at 0, 1 x 104, 1 x 105, 1 x 106 or 1 x 107 CFU g-1 diet (denoted as CG, CB1, CB2, CB3 and CB4, respectively) for 56 days. Then 45 fish from each group were intraperitoneally injected with Streptococcus agalactiae, and the mortality was recorded for 14 days. The results showed that dietary C. butyricum significantly improved the specific growth rate (SGR) and feed intake in the CB2 group and decreased the cumulative mortality post-challenge with S. agalactiae in the CB2, CB3 and CB4 groups. The serum total antioxidant capacity and intestinal interleukin receptor-associated kinase-4 gene expression were significantly increased, and serum malondialdehyde content and diamine oxidase activity were significantly decreased in the CB1, CB2, CB3 and CB4 groups. Serum complement 3 and complement 4 concentrations and intestinal gene expression of tumour necrosis factor α, interleukin 8, and myeloid differentiation factor 88 were significantly higher in the CB2, CB3 and CB4 groups. Intestinal toll-like receptor 2 gene expression was significantly upregulated in the CB3 and CB4 groups. Dietary C. butyricum increased the diversity of the intestinal microbiota and the relative abundance of beneficial bacteria (such as Bacillus), and decreased the relative abundance of opportunistic pathogenic bacteria (such as Aeromonas) in the CB2 group. These results revealed that dietary C. butyricum at a suitable dose enhanced growth performance, elevated humoral and intestinal immunity, regulated the intestinal microbial components, and improved disease resistance in tilapia. The optimal dose was 1 x 105 CFU g-1 diet.

Enhancement of Macrophage Function by the Antimicrobial Peptide Sublancin Protects Mice from Methicillin-Resistant Staphylococcus aureus.

Methicillin-resistant Staphylococcus aureus (MRSA) is the major pathogen responsible for community and hospital bacterial infections. Sublancin, a glucosylated antimicrobial peptide isolated from Bacillus subtilis 168, possesses antibacterial infective effects. In this study, we investigated the role and anti-infection mechanism of sublancin in a mouse model of MRSA-induced sublethal infection. Sublancin could modulate innate immunity by inducing the production of IL-1ß, IL-6, TNF-α, and nitric oxide, enhancing phagocytosis and MRSA-killing activity in both RAW264.7 cells and mouse peritoneal macrophages. The enhanced macrophage function by the peptide in vitro correlated with stronger protective activity in vivo in the MRSA-invasive sublethal infection model. Macrophage activation by sublancin was found to be partly dependent on TLR4 and the NF-κB and MAPK signaling pathways. Moreover, oral administration of sublancin increased the frequencies of CD4+ and CD8+ T cells in mesenteric lymph nodes. The protective activity of sublancin was associated with in vivo augmenting phagocytic activity of peritoneal macrophages and partly improving T cell-mediated immunity. Macrophages thus represent a potentially pivotal and novel target for future development of innate defense regulator therapeutics against S. aureus infection.

The effects of dietary cottonseed meal and oil supplementation on laying performance and egg quality of laying hens.

Cottonseed meal (CSM) and cottonseed oil (CSO), two cottonseed products, are rich in protein and lipids, respectively, but their use is limited by antinutritional factors in the products. This study investigated the effect of different dietary levels of CSM and CSO supplementation on the laying performance and egg quality of laying hens. A total of 162 24-week-old Hy-Line brown laying hens were randomly assigned to diets supplemented with 0, 6%, or 12% CSM and 0, 2%, or 4% CSO in a 3 × 3 factorial design. During the 8-week feeding trial, laying performance and egg quality parameters were measured weekly. Furthermore, a texture profile analysis (TPA) of the egg yolks was conducted, and the fatty acid profiles and protein composition of the yolks were measured to further determine egg quality. CSM supplementation decreased (p < 0.01) egg production and feed efficiency and increased (p < 0.01) yolk color, eggshell rate, and shell thickness, but had no significant effects on the TPA parameters, fatty acid profiles, and protein components of egg yolks. CSO supplementation resulted in decreases (p < 0.01) in egg production, egg weight, and feed efficiency and an increase (p < 0.01) in yolk color. In addition, CSO supplementation with two weeks of cold storage changed the physical properties of boiled egg yolks, as indicated by increased (p < 0.01) hardness, springiness, cohesiveness, and chewiness. Furthermore, 4% CSO supplementation increased the ratio of saturated/monounsaturated fatty acids (SAFA/MUFA) and the protein content of egg yolks, which was accompanied by a modified protein composition. These results indicate that CSM supplementation reduces laying performance and egg quality, and CSO supplementation decreases laying performance and results in egg yolk hardening by modifying its components.

The response of glandular gastric transcriptome to T-2 toxin in chicks.

This study was conducted to determine the effect of T-2 toxin on the transcriptome of the glandular stomach in chicks using RNA-sequencing (RNA-Seq). Four groups of 1-day-old Cobb male broilers (n = 4 cages/group, 6 chicks/cage) were fed a corn-soybean-based diet (control) and control supplemented with T-2 toxin at 1.0, 3.0, and 6.0 mg/kg, respectively, for 2 weeks. The histological results showed that dietary supplementation of T-2 toxin at 3.0 and 6.0 mg/kg induced glandular gastric injury including serious inflammation, increased inflammatory cells, mucosal edema, and necrosis and desquamation of the epithelial cells in the glandular stomach of chicks. RNA-Seq analysis revealed that there were 671, 1393, and 1394 genes displayed ≥2 (P < 0.05) differential expression in the dietary supplemental T-2 toxin at 1.0, 3.0, and 6.0 mg/kg, respectively, compared with the control group. Notably, 204 differently expressed genes had shared similar changes among these three doses of T-2 toxin. GO and KEGG pathway analysis results showed that many genes involved in oxidation-reduction process, inflammation, wound healing/bleeding, and apoptosis/carcinogenesis were affected by T-2 toxin exposure. In conclusion, this study systematically elucidated toxic mechanisms of T-2 toxin on the glandular stomach, which might provide novel ideas to prevent adverse effects of T-2 toxin in chicks.

Selenium Deficiency Aggravates Aflatoxin B1-Induced Immunotoxicity in Chick Spleen by Regulating 6 Selenoprotein Genes and Redox/Inflammation/Apoptotic Signaling.

BACKGROUND: Selenium (Se) plays a protective role in aflatoxin B1 (AFB1)-induced splenic immunotoxicity in chicks. OBJECTIVE: This study was designed to reveal the underlying mechanism of Se-mediated protection against AFB1-induced splenic injury in broilers. METHODS: Four groups of 1-d-old Cobb male broilers (n = 5 cages/diet, 6 chicks/cage) were arranged in a 3-wk 2 × 2 factorial design trial whereby they were fed an Se-deficient, corn- and soy-based diet [base diet (BD), 36 µg Se/kg], BD plus 1.0 mg AFB1/kg, BD plus 0.3 mg Se/kg, or BD plus 1.0 mg AFB1/kg and 0.3 mg Se/kg (as 2-hydroxy-4-methylselenobutanoic acid). Serum and spleen were collected at week 3 to assay for cytokines, histology, redox status, selected inflammation- and apoptosis-related genes and proteins, and the selenogenome. RESULTS: Dietary AFB1 induced growth retardation and spleen injury, decreasing (P < 0.05) body weight gain, feed intake, feed conversion efficiency, and serum interleukin-1ß by 17.8-98.1% and increasing (P < 0.05) the spleen index and serum interleukin-6 by 37.6-113%. It also reduced the splenic lymphocyte number, the white pulp region, and histiocyte proliferation in Se-adequate groups. However, Se deficiency aggravated (P < 0.05) these AFB1-induced alterations by 16.2-103%. Moreover, Se deficiency decreased (P < 0.05) splenic glutathione peroxidase (GPX) activity and glutathione-S transferase and glutathione concentrations by 35.6-89.4% in AFB1-exposed groups. Furthermore, Se deficiency upregulated (P < 0.05) the apoptotic (Caspase 3 and Caspase 9) and antimicrobial (ß defensin 1 and 2) genes, but downregulated (P < 0.05) antiapoptotic (B-cell lymphoma 2) and inflammatory (E3 ubiquitin-protein ligase CBL-B) genes at the mRNA and/or protein level in AFB1 supplementation groups. Additionally, Se deficiency downregulated (P < 0.05) GPX3, thioredoxin reductase 1 (TXNRD 1), GPX4, and selenoprotein (SELENO) S, and upregulated (P < 0.05) SELENOT and SELENOU in spleen in AFB1 administered groups. CONCLUSIONS: Dietary Se deficiency exacerbated AFB1-induced spleen injury in chicks, partially through the regulation of oxidative stress, inflammatory and apoptotic signaling, and 6 selenoproteins.