Phospholipase D Mediates Glutamine-Induced mTORC1 Activation to Promote Porcine Intestinal Epithelial Cell Proliferation.

BACKGROUND: The intestinal epithelium is one of the fastest self-renewal tissues in the body, and glutamine plays a crucial role in providing carbon and nitrogen for biosynthesis. In intestinal homeostasis, phosphorylation-mediated signaling networks that cause altered cell proliferation, differentiation, and metabolic regulation have been observed. However, our understanding of how glutamine affects protein phosphorylation in the intestinal epithelium is limited, and identifying the essential signaling pathways involved in regulating intestinal epithelial cell growth is particularly challenging. OBJECTIVES: This study aimed to identify the essential proteins and signaling pathways involved in glutamine's promotion of porcine intestinal epithelial cell proliferation. METHODS: Phosphoproteomics was applied to describe the protein phosphorylation landscape under glutamine treatment. Kinase-substrate enrichment analysis was subjected to predict kinase activity and validated by qRT-PCR and Western blotting. Cell Counting Kit-8, glutamine rescue experiment, chloroquine treatment, and 5-fluoro-2-indolyl deschlorohalopemide inhibition assay revealed the possible underlying mechanism of glutamine promoting porcine intestinal epithelial cell proliferation. RESULTS: In this study, glutamine starvation was found to significantly suppress the proliferation of intestinal epithelial cells and change phosphoproteomic profiles with 575 downregulated sites and 321 upregulated sites. Interestingly, phosphorylation of eukaryotic initiation factor 4E-binding protein 1 at position Threonine70 was decreased, which is a crucial downstream of the mechanistic target of rapamycin complex 1 (mTORC1) pathway. Further studies showed that glutamine supplementation rescued cell proliferation and mTORC1 activity, dependent on lysosomal function and phospholipase D activation. CONCLUSION: In conclusion, glutamine activates mTORC1 signaling dependent on phospholipase D and a functional lysosome to promote intestinal epithelial cell proliferation. This discovery provides new insight into regulating the homeostasis of the intestinal epithelium, particularly in pig production.

Association between metabolites in tryptophan-kynurenine pathway and inflammatory bowel disease: a two-sample Mendelian randomization.

Previous observational studies have suggested an association between tryptophan (TRP)-kynurenine (KYN) pathway and inflammatory bowel disease (IBD). However, whether there is a causal relationship among them remains unclear. Therefore, a two-sample Mendelian randomization (MR) study was conducted to explore the potential causal effects of crucial metabolites in TRP-KYN pathway on IBD and its subtypes. Using summary data from genome-wide association studies, a two-sample MR was employed to evaluate the genetic associations between TRP and KYN as exposures and IBD as an outcome. The inverse variance weighted method was used as the primary MR analysis, with MR-Egger, weighted mode, simple mode, and weighted median methods as complementary analyses. The odds ratios (OR) and 95% confidence intervals (CI) were determined for TRP-IBD (OR 0.739, 95% CI [0.697; 0.783]), TRP-UC (OR 0.875, 95% CI [0.814; 0.942]), TRP-CD (OR 0.685, 95% CI [0.613; 0.765]), KYN-IBD (OR 4.406, 95% CI [2.247; 8.641]), KYN-UC (OR 2.578, 95% CI [1.368; 4.858], and KYN-CD (OR 13.516, 95% CI [4.919; 37.134]). Collectively, the MR analysis demonstrated a significant protective association between TRP and IBD, whereas KYN was identified as a risk factor for IBD.

Glutamine Regulates Gene Expression Profiles to Increase the Proliferation of Porcine Intestinal Epithelial Cells and the Expansion of Intestinal Stem Cells.

The intestinal epithelium is known for its rapid self-renewal, and glutamine is crucial in providing carbon and nitrogen for biosynthesis. However, understanding how glutamine affects gene expression in the intestinal epithelium is limited, and identifying the essential genes and signals involved in regulating intestinal epithelial cell growth is particularly challenging. In this study, glutamine supplementation exhibited a robust acceleration of intestinal epithelial cell proliferation and stem cell expansion. RNA sequencing indicated diverse transcriptome changes between the control and glutamine supplementation groups, identifying 925 up-regulated and 1152 down-regulated genes. The up-regulated DEGs were enriched in the KEGG pathway of cell cycle and GO terms of DNA replication initiation, regulation of phosphatidylinositol 3-kinase activity, DNA replication, minichromosome maintenance protein (MCM) complex, and ATP binding, whereas the down-regulated DEGs were enriched in the KEGG pathway of p53 signaling pathway, TNF signaling pathway, and JAK-STAT signaling pathway and GO terms of inflammatory response and intrinsic apoptotic signaling pathway in response to endoplasmic reticulum stress. Furthermore, GSEA analysis revealed a significant up-regulation of the cell cycle, DNA replication initiation, ATP-dependent RNA helicase activity, and down-regulation of the TNF signaling pathway. The protein-protein association network of the intersecting genes highlighted the significance of DNA replication licensing factors (MCM3, MCM6, and MCM10) in promoting intestinal epithelial growth in response to glutamine. Based on these findings, we propose that glutamine may upregulate DNA replication licensing factors, leading to increased PI3K/Akt signaling and the suppression of TNF, JAK-STAT, and p53 pathways. Consequently, this mechanism results in the proliferation of porcine intestinal epithelial cells and the expansion of intestinal stem cells.

Mechanofluorochromic behaviours of functionalized carbazole-based difluoroboron compounds with different aryl substituents moieties.

To better understand the relationship between molecular structure and mechanofluorochromic characteristics, three carbazole-based N^O-chelated difluoroboron compounds (Cz-S-BF2 , Cz-PhNp-S-BF2 , and Cz-BNp-S-BF2 ) with different aryl substituents moieties were designed and synthesized. The mechanofluorochromic behaviours of Cz-S-BF2 (luminescence from bluish-green to yellowish-green, emission from 504 to 535 nm) without aryl substitution and Cz-PhNp-S-BF2 (luminescence from green and yellow, emission from 521 to 557 nm) with a phenyl-naphthalene group underwent reversible conversion using the grinding-fuming process. For Cz-BNp-S-BF2 this was not apparent due to the well coplanarity of the binaphthalene moiety. Mechanofluorochromic properties were demonstrated through XRD patterns measurement. We envisage that this study will provide a practicable reference to acquire organic molecules with mechanofluorochromic characteristics.

Single-cell and bulk transcriptomics reveals M2d macrophages as a potential therapeutic strategy for mucosal healing in ulcerative colitis.

Mucosal healing is essential for treating ulcerative colitis (UC), which results from imbalanced macrophage polarization and dysregulated inflammatory responses. However, the mechanisms of cellular communication and signal transduction that regulate mucosal healing among macrophage subtypes require further investigation. We use bulk and single-cell RNA sequencing analysis to reveal that macrophage subtypes vary in different UC states. At the same time, chemokine and angiogenesis signaling is strongly associated with M2 macrophage's infiltrated proportion. To get more insight into subtypes of macrophages in mucosal healing, we divided macrophages into M1, M2b, and M2d macrophages. Based on the differentially expressed genes (DEGs) between M2d and M1 macrophages, KEGG and GO analysis highlights M2d macrophages' ability to alleviate inflammation and promote epithelial healing. Trajectory analysis revealed opposite differentiation of macrophage subsets between UC and healthy groups, with M1 and M2d macrophages coexisting in the same differentiation branch under UC conditions. Along the pseudotime axis, CCL3 and VEGFA expression increased in UC, while IL10RA remained stable in UC but increased in healthy controls. CellChat identified CCL3-CCR1 has strong communication between M1 and M2d macrophages, while the IL10 signaling pathway is activated explicitly in M2d macrophages to mitigate inflammation and promote epithelial healing. We also speculate that high levels of VEGFA activate endothelial cells expressing VEGFR and worsen inflammation. To conclude, we suggested IL10 and VEGF signaling in M2d macrophages as potential therapeutic targets for mucosal healing. However, it is necessary to establish reliable methods for isolating and purifying M2d macrophages before these targets can be effectively utilized.

Some key issues in building a "source network load storage" complementary energy internet in China.

The key to "dual carbon" lies in low-carbon energy systems. The energy internet can coordinate upstream and downstream "source network load storage" to break energy system barriers and promote carbon reduction in energy production and consumption processes. This article first introduces the basic concepts and key technologies of the energy internet from the current situation of energy supply and demand in China. Second, this paper proposes to create an energy internet with coordinated and complementary "source network load storage" and to construct a new type of power system with six new characteristics in this context. Finally, combined with an example of the energy internet demonstration project, this paper analyses and summarizes the value creation and business type innovation of the energy internet from three aspects: power market mechanisms, comprehensive energy services, and low-carbon energy diversification, and it looks ahead to the future direction of energy internet construction.

Kynurenine pathway metabolites modulated the comorbidity of IBD and depressive symptoms through the immune response.

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, is defined as chronic inflammation in the gastrointestinal tract. Notably, more than 20% of people with IBD experience depressive symptoms. Understanding the immunological mechanism of chronic intestinal inflammation on cognitive behavior has become a key research focus. Previous studies have shown that a dysregulated immune response contributes to chronic inflammation and depressive symptoms. The tolerant phenotype exhibited by immune cells regulates the course of chronic inflammation in distinct ways. In addition, neuroglia, such as microglia and astrocytes specific to the brain, are also influenced by deregulated inflammation to mediate the development of depressive symptoms. The kynurenine pathway (KP), a significant tryptophan metabolic pathway, transforms tryptophan into a series of KP metabolites that modulate chronic inflammation and depressive symptoms. In particular, indoleamine 2,3-dioxygenase 1 (IDO1), a rate-limiting enzyme in the KP, is activated by chronic inflammation and leads to the production of kynurenine. In addition, disruption of the brain-gut axis induced by IBD allows kynurenine to cross the blood-brain barrier (BBB) and form a series of neuroactive kynurenine metabolites in glial cells. Among them, quinolinic acid continuously accumulates in the brain, indicating depression. Thus, KP metabolites are critical for driving the comorbidity of IBD and depressive symptoms. In this review, the pathological mechanism of KP metabolite-mediated chronic intestinal inflammation and depressive symptoms by regulating the immune response is summarized according to the latest reports.

Gut-on-a-chip for disease models.

The intestinal tract is a vital organ responsible for digestion and absorption in the human body and plays an essential role in pathogen invasion. Compared with other traditional models, gut-on-a-chip has many unique advantages, and thereby, it can be considered as a novel model for studying intestinal functions and diseases. Based on the chip design, we can replicate the in vivo microenvironment of the intestine and study the effects of individual variables on the experiment. In recent years, it has been used to study several diseases. To better mimic the intestinal microenvironment, the structure and function of gut-on-a-chip are constantly optimised and improved. Owing to the complexity of the disease mechanism, gut-on-a-chip can be used in conjunction with other organ chips. In this review, we summarise the human intestinal structure and function as well as the development and improvement of gut-on-a-chip. Finally, we present and discuss gut-on-a-chip applications in inflammatory bowel disease (IBD), viral infections and phenylketonuria. Further improvement of the simulation and high throughput of gut-on-a-chip and realisation of personalised treatments are the problems that should be solved for gut-on-a-chip as a disease model.

Pillararene-functionalized rhodium nanoparticles for efficient catalytic reduction and photothermal sterilization.

Pillar[5]arene-functionalized rhodium nanoparticles (Rh@CPA NPs) are first synthesized via a facile one-pot chemical reduction method. Rh@CPA NPs with good reusability and biocompatibility show excellent catalytic activities in reducing toxic nitrophenols and azo dyes, and also exhibit superior photothermal ablation capability towards Staphylococcus aureus under 808 nm laser irradiation. This work suggests that the supramolecular capping strategy could be used to construct novel hybrid materials for various applications.

L-glutamate requires ß-catenin signalling through Frizzled7 to stimulate porcine intestinal stem cell expansion.

Intestinal stem cells (ISCs) decode and coordinate various types of nutritional information from the diet to support the crypt-villus axis architecture, but how specific dietary molecules affect intestinal epithelial homeostasis remains unclear. In the current study, L-glutamate (Glu) supplementation in either a nitrogen-free diet (NFD) or a corn-soybean meal diet (CSMD) stimulated gut growth and ISC expansion in weaned piglets. Quantitative proteomics screening identified the canonical Wnt signalling pathway as a central regulator of intestinal epithelial development and ISC activity in vivo. Importantly, the Wnt transmembrane receptor Frizzled7 (FZD7) was upregulated in response to dietary Glu patterns, and its perturbations in intestinal organoids (IOs) treated with a specific inhibitor and in FZD7-KO IPEC-J2 cells disrupted the link between Glu inputs and ß-catenin signalling and a subsequent reduction in cell viability. Furthermore, co-localization, coimmunoprecipitation (Co-IP), isothermal titration calorimetry (ITC), and microscale thermophoresis (MST) revealed that Glu served as a signalling molecule directly bound to FZD7. We propose that FZD7-mediated integration of the extracellular Glu signal controls ISC proliferation and differentiation, which provides new insights into the crosstalk of nutrients and ISCs.

Fluorescence immunoassay for the targeted determination of trace Listeria monocytogenes based on immunomagnetic separation and CdZnTe quantum dot indication.

Infections from invasive Listeria monocytogenes (L. monocytogenes) frequently occur in food and can cause high morbidity and death. Thus, the sensitive, specific, and rapid detection of L. monocytogenes is critical for ensuring food safety and public health. Herein, a fluorescence immunoassay for trace L. monocytogenes detection was designed based on guinea pig antibody-functionalized magnetic nanoparticles (Fe3O4 NPs/pAb1) and rabbit antibody-anchored CdZnTe quantum dots (CdZnTe QDs/pAb2). Because of the antibody-directed magnetic separation and long-wave fluorescent emission for CdZnTe QD indication, the constructed immunoassay strategy presented excellent anti-interference performance toward a biological matrix. The immunosensor exhibited a wide detection range of 1 to 109 CFU mL-1 for L. monocytogenes and a low limit of detection (LOD) of 1 CFU mL-1, achieving an exceptionally sensitive detection of trace L. monocytogenes. Meanwhile, the immunosensor showed good specificity and had a short time-consumption of 60 min to realize the accurate determination of trace Listeria monocytogenes in spiked tap water and pasteurized milk samples.

Intestinal Models for Personalized Medicine: from Conventional Models to Microfluidic Primary Intestine-on-a-chip.

Intestinal dysfunction is frequently driven by abnormalities of specific genes, microbiota, or microenvironmental factors, which usually differ across individuals, as do intestinal physiology and pathology. Therefore, it's necessary to develop personalized therapeutic strategies, which are currently limited by the lack of a simulated intestine model. The mature human intestinal mucosa is covered by a single layer of columnar epithelial cells that are derived from intestinal stem cells (ISCs). The complexity of the organ dramatically increases the difficulty of faithfully mimicking in vivo microenvironments. However, a simulated intestine model will serve as an indispensable foundation for personalized drug screening. In this article, we review the advantages and disadvantages of conventional 2-dimensional models, intestinal organoid models, and current microfluidic intestine-on-a-chip (IOAC) models. The main technological strategies are summarized, and an advanced microfluidic primary IOAC model is proposed for personalized intestinal medicine. In this model, primary ISCs and the microbiome are isolated from individuals and co-cultured in a multi-channel microfluidic chip to establish a microengineered intestine device. The device can faithfully simulate in vivo fluidic flow, peristalsis-like motions, host-microbe crosstalk, and multi-cell type interactions. Moreover, the ISCs can be genetically edited before seeding, and monitoring sensors and post-analysis abilities can also be incorporated into the device to achieve high-throughput and rapid pharmaceutical studies. We also discuss the potential future applications and challenges of the microfluidic platform. The development of cell biology, biomaterials, and tissue engineering will drive the advancement of the simulated intestine, making a significant contribution to personalized medicine in the future. Graphical abstract The intestine is a primary organ for digestion, absorption, and metabolism, as well as a major site for the host-commensal microbiota interaction and mucosal immunity. The complexity of the organ dramatically increases the difficulty of faithfully mimicking in vivo microenvironments, though physiological 3-dimensional of the native small intestinal epithelial tissue has been well documented. An intestinal stem cells-based microfluidic intestine-on-a-chip model that faithfully simulate in vivo fluidic flow, peristalsis-like motions, host-microbe crosstalk, and multi-cell type interactions will make a significant contribution.

MG53 suppresses tumor progression and stress granule formation by modulating G3BP2 activity in non-small cell lung cancer.

BACKGROUND: Cancer cells develop resistance to chemotherapeutic intervention by excessive formation of stress granules (SGs), which are modulated by an oncogenic protein G3BP2. Selective control of G3BP2/SG signaling is a potential means to treat non-small cell lung cancer (NSCLC). METHODS: Co-immunoprecipitation was conducted to identify the interaction of MG53 and G3BP2. Immunohistochemistry and live cell imaging were performed to visualize the subcellular expression or co-localization. We used shRNA to knock-down the expression MG53 or G3BP2 to test the cell migration and colony formation. The expression level of MG53 and G3BP2 in human NSCLC tissues was tested by western blot analysis. The ATO-induced oxidative stress model was used to examine the effect of rhMG53 on SG formation. Moue NSCLC allograft experiments were performed on wild type and transgenic mice with either knockout of MG53, or overexpression of MG53. Human NSCLC xenograft model in mice was used to evaluate the effect of MG53 overexpression on tumorigenesis. RESULTS: We show that MG53, a member of the TRIM protein family (TRIM72), modulates G3BP2 activity to control lung cancer progression. Loss of MG53 results in the progressive development of lung cancer in mg53-/- mice. Transgenic mice with sustained elevation of MG53 in the bloodstream demonstrate reduced tumor growth following allograft transplantation of mouse NSCLC cells. Biochemical assay reveals physical interaction between G3BP2 and MG53 through the TRIM domain of MG53. Knockdown of MG53 enhances proliferation and migration of NSCLC cells, whereas reduced tumorigenicity is seen in NSCLC cells with knockdown of G3BP2 expression. The recombinant human MG53 (rhMG53) protein can enter the NSCLC cells to induce nuclear translation of G3BP2 and block arsenic trioxide-induced SG formation. The anti-proliferative effect of rhMG53 on NSCLC cells was abolished with knockout of G3BP2. rhMG53 can enhance sensitivity of NSCLC cells to undergo cell death upon treatment with cisplatin. Tailored induction of MG53 expression in NSCLC cells suppresses lung cancer growth via reduced SG formation in a xenograft model. CONCLUSION: Overall, these findings support the notion that MG53 functions as a tumor suppressor by targeting G3BP2/SG activity in NSCLCs.

l-Carnosine Protects Against Deoxynivalenol-Induced Oxidative Stress in Intestinal Stem Cells by Regulating the Keap1/Nrf2 Signaling Pathway.

SCOPE: The intestinal epithelium is nourished by various nutrients and subjected to persistent and widespread feed-derived mycotoxin stress. l-Carnosine (LC) possesses robust antioxidant activity; however, its role in protecting intestinal mucosa against deoxynivalenol (DON) is still unclear. METHODS AND RESULTS: In this study, 300 mg kg-1 BW LC and 3 mg kg-1 BW DON are orally administered to mice either alone or in combination for 10 days to investigate the role of LC in protecting the intestine against DON. This study found that LC alleviates the growth retardation of mice and repairs the damaged jejunal structure and barrier functions under DON exposure. LC rescues the intestinal stem cells (ISCs), increases the growth advantage in enteroids derived from jejunal crypts of mice in each group ex vivo, improves the proliferation and apoptosis of intestinal cells, and promotes ISC differentiation into absorptive cells, goblet cells, and Paneth cells. Furthermore, LC activates Nrf2 signaling by binding to Keap1 to reverse the striking DON-induced increase in ROS levels. CONCLUSION: The study findings unveil that LC potentiates the antioxidant capacity of ISCs by regulating the Keap1/Nrf2 signaling pathway, which contributes to the intestinal epithelial regeneration response to DON insult.

Enhanced performance of a surface plasmon resonance-based immunosensor for the detection of glycocholic acid.

The concentration of glycocholic acid (GCA) in urine and blood is an important biomarker for liver cancer. Monitoring of GCA depends to a large extent on the availability of appropriate analytical techniques. In this work, based on the immobilization of GCA-OVA onto the sensor chip surface, a label-free competitive inhibition immunoassay for the determination of GCA with the surface plasmon resonance (SPR) technique was developed. The proposed SPR immunosensor is simple to prepare, recyclable and exhibits excellent sensitivity to GCA (a linear range of 13.3-119.4 ng mL-1 and a limit of detection (LOD) of 2.5 ng mL-1), which was 14 times lower than that of the traditional immunoassay. Excellent recoveries and correlation between these two methods were observed (R2 = 0.995). Hence, it can be proved that the SPR immunosensor could be used to achieve rapid and sensitive quantitative detection of GCA in real urine samples and meet clinical needs.

The preparation of bifunctional hybrid nano-flowers and their application in the enzyme-linked immunosorbent assay for Helicobacter pylori detection.

As the infection by Helicobacter pylori (H. pylori, HP) remains for a lifetime and may induce diseases such as gastric cancer, it is vital to detect and diagnose it. A new non-invasive indirect enzyme-linked immunosorbent assay (iELISA) method based on nano-flowers (NFs) is very advantageous for the sensitive detection of HP. Furthermore, the established iELISA method based on the organic-inorganic bifunctional hybrid nano-flowers including rabbit polyclonal antibody of HP labeled with peroxidase from horseradish (R-HP-Ab-HRP@Cu2+ NFs) showed linearity with HP at a concentration of 0-105 CFU mL-1 (R2 = 0.9997). Moreover, the limit of detection (LOD) reached 50 CFU mL-1, and not only was the detection sensitivity 20 times higher than that based on rabbit polyclonal antibody of HP labeled with peroxidase from horseradish (R-HP-Ab-HRP) but also the stability of R-HP-Ab-HRP in NFs was improved. In addition, the OD450 nm value was still linearly related to the concentration of HP at a range of 0-105 CFU mL-1 (R2 = 0.9952) with a LOD of 50 CFU mL-1 in an artificial saliva system. This study provided a sensitive, low-cost and convenient method for the non-invasive detection of HP.

A colorimetric sensing strategy based on enzyme@metal-organic framework and oxidase-like IrO2/MnO2 nanocomposite for α-glucosidase inhibitor screening.

A highly sensitive colorimetric sensing strategy based on enzyme@metal-organic framework (GAA@Cu-MOF) and IrO2/MnO2 nanocomposite was exploited innovatively for screening of α-glucosidase (GAA) inhibitors. IrO2/MnO2 nanocomposite exhibits excellent oxidase-mimicking activity which can directly catalyze the oxidation of 3,3,5,5,-tetramethylbenzidine (TMB) into a blue product with an absorption maximum at 652 nm. And GAA@Cu-MOF can decompose L-ascorbic acid-2-O-α-D-glucopyranosyl (AAG) to ascorbic acid (AA). The produced AA can destroy the IrO2/MnO2 nanocomposite and reduce its oxidase-like activity. However, the generation of AA is restricted when GAA inhibitors are added to the system, which allows the oxidase-like activity of the IrO2/MnO2 nanocomposite to be maintained. In view of this, a method for screening of GAA inhibitors was developed. In addition to enhancing the stability of GAA, the method can also effectively avoid the potential interference of H2O2 in the screening process of GAA inhibitors, which helps to improve the sensitivity of the method. Therefore, highly sensitive determination for acarbose and ascorbic acid are achieved with detection limits of 6.27 nM and 1.23 µM, respectively. The proposed method was successfully applied to screen potential GAA inhibitors from oleanolic acid derivatives. Graphical abstract.

Production and characteristics of a novel chicken egg yolk antibody (IgY) against periodontitis-associated pathogens.

Periodontitis is a bacterial biofilm-induced oral disease, mostly caused by Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) and Porphyromonas gingivalis (P. gingivalis). Oral administration of chicken egg yolk antibody (IgY) is a promising nutritional strategy to control pathogen infections. The objective of this study was to produce an A. actinomycetemcomitans- and P. gingivalis-specific IgY and evaluate its effects on bacterial agglutination and biofilm formation. Thirty laying hens were immunized with a complex of lysate containing typical molecular weights of membrane proteins of A. actinomycetemcomitans and P. gingivalis. IgY was isolated by polyethylene glycol 6000 and ammonium sulfate and purified by dialysis. The results of enzyme-linked immunosorbent assay showed that the obtained IgY were specific to both A. actinomycetemcomitans and P. gingivalis. In addition, immunoelectron microscopy scanning and crystal violet staining showed that the IgY could bind to cell wall of the pathogens and efficiently accelerate agglutination and inhibit biofilm formation. Furthermore, the activity of the IgY remained stable at different temperature, pH, and storage period. This is the first report that a novel two-in-one IgY was produced to modulate the agglutination and biofilm formation of A. actinomycetemcomitans and P. gingivalis, suggesting the potential of IgY to control periodontitis caused by oral pathogens.

An in vitro and in vivo study of the brain-targeting effects of an epidermal growth factor-functionalized cholera toxin-like chimeric protein.

The development of neuroprotective drugs has proven to be extremely difficult because of the blood-brain barrier. Intranasal administration is thought to transport the drug from the nasal cavity along the olfactory and trigeminal nerves to the brain, thus bypassing the blood-brain barrier. However, macromolecular protein drugs have low delivery efficiency via this route in general. We hypothesized that an innocuous cholera toxin-like chimeric protein could better enhance the efficiency of protein delivery through the intranasal route. To test this hypothesis, we designed an enhanced green fluorescent protein (EGFP) chimera to evaluate the effect of the cholera toxin (CT) as a carrier for drug delivery into the brain. Then, the EGFP was replaced with epidermal growth factor (EGF) in the chimeric protein, and the therapeutic effect of the new chimeric protein was studied in an LPS-induced neuritis mouse model. The results suggest that the CT-like chimeric protein can bypass the blood-brain barrier and enter the brain in approximately 30 min. This EGF chimeric protein can effectively protect the spatial cognitive ability of and confer anti-anxiety protection to mice. The results indicate that cholera toxin-like chimeric proteins are potential tools for effectively delivering macromodecular drugs into the brain through intranasal administration.

Wnt/ß-catenin-mediated heat exposure inhibits intestinal epithelial cell proliferation and stem cell expansion through endoplasmic reticulum stress.

Heat stress induced by continuous high ambient temperatures or strenuous exercise in humans and animals leads to intestinal epithelial damage through the induction of intracellular stress response. However, the precise mechanisms involved in the regulation of intestinal epithelial cell injury, especially intestinal stem cells (ISCs), remain unclear. Thereby, in vitro a confluent monolayer of IPEC-J2 cells was exposed to the high temperatures (39, 40, and 41°C), the IPEC-J2 cell proliferation, apoptosis, differentiation, and barrier were determined, as well as the expression of GRP78, which is a marker protein of endoplasmic reticulum stress (ERS). The Wnt/ß-catenin pathway-mediated regenerative response was validated using R-spondin 1 (Rspo1). And ex-vivo, three-dimensional cultured enteroids were developed from piglet jejunal crypt and employed to assess the ISC activity under heat exposure. The results showed that exposure to 41°C for 72 hr, rather than 39°C and 40°C, decreased IPEC-J2 cell viability, inhibited cell proliferation and differentiation, induced ERS and cell apoptosis, damaged barrier function and restricted the Wnt/ß-catenin pathway. Nevertheless, Wnt/ß-catenin reactivation via Rspo1 protects the intestinal epithelium from heat exposure-induced injury. Furthermore, exposure to 41°C for 24 hr reduced ISC activity, stimulated crypt-cell apoptosis, upregulated the expression of GRP78 and caspase-3, and downregulated the expression of ß-catenin, Lgr5, Bmi1, Ki67, KRT20, ZO-1, occludin, and claudin-1. Taken together, we conclude that heat exposure induces ERS and downregulates the Wnt/ß-catenin signaling pathway to disrupt epithelial integrity by inhibiting the intestinal epithelial cell proliferation and stem cell expansion.