Peptide Expression Research Articles

Mechanism of action of adapalene for treating EGFR-TKI-induced skin disorder.

Skin disorders are the most common side effect associated with epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) therapy. It is important to manage skin lesions. Adapalene has been used to treat skin lesions caused by EGFR-TKIs in some cases. The aim of this study was to investigate the functional mechanism of adapalene in erlotinib-induced skin disorder. To analyze the effect of adapalene on skin rash, afatinib and adapalene were administered to mice. The relationship between the concentration of adapalene and skin disorders was also examined by analyzing AQP3 expression. A skin lesion model was experimentally established in human skin keratinocytes (HaCaT) by using erlotinib with TNF-α and IL-1β. We used qRT-PCR to analyze chemokine-induced inflammation and western blotting to analyze the effects of adapalene on the NF-κB signaling pathway. Antimicrobial peptides and adhesion factors were also examined using qRT-PCR. Mice administered 0.01% adapalene had less skin inflammation than mice treated with afatinib alone. The expression level of AQP3 decreased in an adapalene concentration-dependent manner. The mRNA levels of proinflammatory cytokines such as CCL2 and CCL27 in HaCaT cells were significantly reduced by adapalene. The expression of an antimicrobial peptide, hBD3, was upregulated after adapalene treatment. Adhesion factors, such as E-cadherin, were significantly downregulated by EGFR-TKI and significantly upregulated by adapalene treatment. Western blot analysis suggested that erlotinib-induced phosphorylation of p65 was decreased by adapalene. We suggest that adapalene may be a possible treatment option for skin disorders induced by EGFR-TKIs.

Wings of Change: aPKC/FoxP-dependent plasticity in steering motor neurons underlies operant self-learning in Drosophila.

Motor learning is central to human existence, such as learning to speak or walk, sports moves, or rehabilitation after injury. Evidence suggests that all forms of motor learning share an evolutionarily conserved molecular plasticity pathway. Here, we present novel insights into the neural processes underlying operant self-learning, a form of motor learning in the fruit fly Drosophila. We operantly trained wild type and transgenic Drosophila fruit flies, tethered at the torque meter, in a motor learning task that required them to initiate and maintain turning maneuvers around their vertical body axis (yaw torque). We combined this behavioral experiment with transgenic peptide expression, CRISPR/Cas9-mediated, spatio-temporally controlled gene knock-out and confocal microscopy. We find that expression of atypical protein kinase C (aPKC) in direct wing steering motoneurons co-expressing the transcription factor FoxP is necessary for this type of motor learning and that aPKC likely acts via non-canonical pathways. We also found that it takes more than a week for CRISPR/Cas9-mediated knockout of FoxP in adult animals to impair motor learning, suggesting that adult FoxP expression is required for operant self-learning. Our experiments suggest that, for operant self-learning, a type of motor learning in Drosophila, co-expression of atypical protein kinase C (aPKC) and the transcription factor FoxP is necessary in direct wing steering motoneurons. Some of these neurons control the wing beat amplitude when generating optomotor responses, and we have discovered modulation of optomotor behavior after operant self-learning. We also discovered that aPKC likely acts via non-canonical pathways and that FoxP expression is also required in adult flies.

Expression of the Antimicrobial Peptide SE-33-A2P, a Modified Analog of Cathelicidin, and an Analysis of Its Properties.

In this study, we developed a method for the expression of the antimicrobial peptide SE-33-A2P in E. coli bacterial cells. The SE-33-A2P peptide consists of A2P and SE-33 peptides and is a retro analog of cathelicidin possessing antimicrobial activity against both Gram-positive and Gram-negative bacteria. Furthermore, the A2P peptide is a self-cleaving peptide. For an efficient expression of the SE-33-A2P peptide, a gene encoding several repetitive sequences of the SE-33 peptide separated by A2P sequences was created. The gene was cloned into a plasmid, with which E. coli cells were transformed. An induction of the product expression was carried out by IPTG after the cell culture gained high density. The inducible expression product, due to the properties of the A2P peptide, was cleaved in the cell into SE-33-A2P peptides. As the next step, the SE-33-A2P peptide was purified using filtration and chromatography. Its activity against both Gram-positive and Gram-negative bacteria, including antibiotic-resistant bacteria, was proved. The developed approach for obtaining a prokaryotic system for the expression of a highly active antimicrobial peptide expands the opportunities for producing antimicrobial peptides via industrial methods.

A191 THE NEURAL SIGNAL, CALCITONIN GENE-RELATED PEPTIDE (CGRG) ENHANCES A REGULATORY PHENOTYPE IN THE HUMAN IL-4-TREATED MACROPHAGE

Abstract Background Interlukin-4 activated human macrophages (M(IL4) promote epithelial wound healing and exert an anti-colitic effect in a murine model. Blood monocyte-derived M(IL4)s from healthy donors and individuals with Crohn’s disease had increased mRNA expression of the calcitonin gene-related peptide (CGRP) receptor chain, RAMP1, raising the issue of neural modulation of the M(IL4)s reparative function. Aims To determine if CGRP-RAMP1 signalling in human IL-4 treated macrophages enhances the anti-colitic phenotype. Methods Peripheral blood mononuclear cells from healthy volunteers (HD) and individuals with Crohn’s disease were cultured on plastic (2h, 37°C) and non-adherent cells removed. The adherent cells were cultured with recombinant hM-CSF (10 ng/ml) for 7 days. The resultant macrophages (2.5×105) were differentiated with IL-4 (48h 10 ng/mL). In other cells, CGRP (10 nM) was added 24h after IL-4 and phenotype assessed by qPCR. Rag1-/- mice were treated with M(IL4)±CGRP (1x106 i.p.): 48h later, colitis was induced by oxazolone. FITC dextran was used to evaluate epithelial barrier integrity. A wound healing assay was conducted using CaCo2 epithelial cells and conditioned medium (CM,1:2 dilution) from the different treatments. Prostaglandin D2 production was evaluated by ELISA and cyclooxygenase (COX)-1 and -2 activity inhibited using SC560 and indomethacin. Results Compared to non-treated macrophages (M(0)), M(IL4)s from HD had increased RAMP1 and CLR mRNA. M(IL4)s treated with CGRP showed enhanced expression of CD206, CCL26, RAMP1 and CCL18. When delivered systemically to oxazolone-treated rag1-/- mice, M(IL4,CGRP) had an anti-colitic effect superior to M(IL4)s from the same healthy blood donor. Use of the the human colon CaCo2 cell in vitro wounding model revealed that CM from M(IL4,CGRP) had increased amounts of TGFb and increased wound-healing capacity compared to matched M(IL4)-CM. Moreover, M(IL4,CGRP)s displayed increased COX-1 and PGD2. CM from M(IL4,CGRP)s treated with indomethacin or SC-560 to inhibit COX1 activity failed to promote repair of wounded CaCo2 cell monolayers. Conclusions Neuronal input is revealed as an important local modifier capable of boosting the anti-colitic effect of autologous M(IL4) transfer to treat enteric inflammation. Funding Agencies CCCHelmsley Charity

Apparent ileal amino acid digestibility, gut morphometrics, and gene expression of peptide and amino acid transporters in broiler chickens fed low-crude-protein diets supplemented with crystalline amino acids with soybean meal, canola meal, or corn DDGS as protein feedstuffs.

We investigated the impact of using canola meal (CM) or corn distillers dried grain soluble (cDDGS) in place of soybean meal (SBM) in low-crude-protein diets supplemented with amino acids (AA) on AA digestibility, gut morphometrics, and AA transporter genes in broiler chicken. On day 0, 540 Cobb 500 male broilers were allocated to six diets in 36-floor pens. The positive control (PC) was a corn-SBM diet with adequate crude protein (CP). The CP level of negative control (NC) was decreased by 45 and 40 g kg-1 relative to PC for grower and finisher phases, respectively. The subsequent two diets had the same CP levels as NC but with cDDGS added at 50 or 125 g kg-1. The last two diets had the same CP as NC but with CM added at 50 or 100 g kg-1. Dietary CP reduction in corn-SBM diets increased (P < 0.05) the digestibility of Lys (88.5%), Met (90.7%), Thr (77.4%), Cys (80.7%), and Gly (84.7%). Increasing levels of cDDGS linearly decreased (P < 0.05) the digestibility of Asp, Cys, Glu, and Ser, whereas increasing CM level linearly decreased (P < 0.05) the digestibility of Cys, Pro, and Ser. The CP reduction in corn-SBM diets produced downward expression of peptide transporter1 and decreased (P < 0.05) absolute pancreas and ileum weight and length of jejunum and ileum. Partial replacement of SBM with alternative protein feedstuffs (cDDGS or CM) in low-CP diets had minimal effects on AA digestibility and mRNA levels of peptides and AA transporters. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Comparison of Protective Effect of Tri-circulator and Coenzyme Q10 on Myocardial Injury and the Mechanism Study by Zebrafish Model.

Tri-Circulator (TC) is a product comprising coenzyme Q10 (CoQ10), Salvia miltiorrhiza, and Panax notoginseng. Individually, each of these constituents has demonstrated protective effects on myocardial injury. The purpose of this study is to evaluate the protective efficacy of TC on heart function and compare the differential effects between CoQ10 and TC. Two myocardial injury models of zebrafish, the hypoxia-reoxygenation model (H/R) and the isoproterenol (ISO, a β-receptor agonist) model, were used in this experiment. The zebrafish subjects were divided into 4 groups: control, H/R, TC, and CoQ10. Heart rate, stroke volume (SV), cardiac output (CO), ejection fraction (EF), fractional area change (FAC), and pericardial height were monitored to assess changes in heart function. The gene expression of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) was studied as markers of injury/stress. TC significantly suppresses elevated heart rate induced by H/R and prevents the decrease of heart rate induced by ISO. It alleviates the pericardial infusion induced by ISO, whereas CoQ10 does not possess a similar effect. Both TC and CoQ10 significantly inhibit the decline in SV, CO, EF, and FAC induced by H/R and ISO, and suppress the expression of ANP and BNP in cardiomyocytes induced by ISO. It is noteworthy that TC demonstrates a more pronounced effect on EF, FAC, ANP, and BNP gene expression compared to CoQ10. Both TC and CoQ10 have a protective effect on myocardial injury of zebrafish. However, TC exhibits a greater efficacy compared to CoQ10 alone in mitigating myocardial injury.

Potential mechanisms for osteopathic manipulative treatment to alleviate migraine-like pain in female rats.

Migraines are the leading cause of disability in the United States, and the use of non-pharmaceutical treatments like osteopathic manipulative treatment (OMT) has shown promise. Despite its potential, the lack of mechanistic understanding has hindered widespread adoption. This study aims to investigate the efficacy of OMT in treating acute migraines and unravel its underlying mechanisms of action. Female rats were subjected to a "two-hit" approach to induce migraine-like pain. This involved bilateral injections of Complete Freund's Adjuvant (CFA) into the trapezius muscle (1st hit) followed by exposure to Umbellulone, a human migraine trigger, on Day 6 post-CFA (2nd hit). Soft tissue and articulatory techniques were applied to the cervical region for acute abortive or repeated prophylactic treatment. Cutaneous allodynia and trigeminal system activation were assessed through behavioral tests and immunohistochemical staining. Following Umbellulone inhalation, CFA-primed rats exhibited periorbital and hind paw allodynia. Immediate application of OMT after Umbellulone inhalation as an abortive treatment partially alleviated cutaneous allodynia. With OMT applied thrice as a prophylactic measure, complete suppression of tactile hypersensitivity was observed. Prophylactic OMT also prevented the increase of c-fos signals in the trigeminal nucleus caudalis and the elevation of calcitonin gene-related peptide expression in trigeminal ganglia induced by CFA and Umbellulone exposure at 2 h post-inhalation. These findings provide mechanistic insights into OMT's migraine-relief potential and underscore its viability as a non-pharmacological avenue for managing migraines.

Human metapneumovirus respiratory infection affects both innate and adaptive intestinal immunity.

Respiratory infections are one of the leading causes of morbidity and mortality worldwide, mainly in children, immunocompromised people, and the elderly. Several respiratory viruses can induce intestinal inflammation and alterations in intestinal microbiota composition. Human metapneumovirus (HMPV) is one of the major respiratory viruses contributing to infant mortality in children under 5 years of age worldwide, and the effect of this infection at the gut level has not been studied. Here, we evaluated the distal effects of HMPV infection on intestinal microbiota and inflammation in a murine model, analyzing several post-infection times (days 1, 3, and 5). Six to eight-week-old C57BL/6 mice were infected intranasally with HMPV, and mice inoculated with a non-infectious supernatant (Mock) were used as a control group. We did not detect HMPV viral load in the intestine, but we observed significant changes in the transcription of IFN-γ in the colon, analyzed by qPCR, at day 1 post-infection as compared to the control group. Furthermore, we analyzed the frequencies of different innate and adaptive immune cells in the colonic lamina propria, using flow cytometry. The frequency of monocyte populations was altered in the colon of HMPV -infected mice at days 1 and 3, with no significant difference from control mice at day 5 post-infection. Moreover, colonic CD8+ T cells and memory precursor effector CD8+ T cells were significantly increased in HMPV-infected mice at day 5, suggesting that HMPV may also alter intestinal adaptive immunity. Additionally, we did not find alterations in antimicrobial peptide expression, the frequency of colonic IgA+ plasma cells, and levels of fecal IgA. Some minor alterations in the fecal microbiota composition of HMPV -infected mice were detected using 16s rRNA sequencing. However, no significant differences were found in β-diversity and relative abundance at the genus level. To our knowledge, this is the first report describing the alterations in intestinal immunity following respiratory infection with HMPV infection. These effects do not seem to be mediated by direct viral infection in the intestinal tract. Our results indicate that HMPV can affect colonic innate and adaptive immunity but does not significantly alter the microbiota composition, and further research is required to understand the mechanisms inducing these distal effects in the intestine.

Expression of Toll-like receptors and host defence peptides in the cecum of chicken challenged with Eimeria tenella.

Chicken coccidiosis, caused by Eimeria protozoa, affects poultry farming. Toll-like receptors (TLRs) and host defence peptides (HDPs) help host innate immune responses to eliminate invading pathogens, but their roles in Eimeria tenella infection remain poorly understood. Herein, 14-day-old chickens were treated orally with 50,000 E. tenella oocysts and the cecum was dissected at different timepoints. mRNA expression of 10 chicken TLRs (chTLRs) and five HDPs was measured by quantitative real-time PCR. chTLR7 and chTLR15 were upregulated significantly at 3 h post-infection while other chTLRs were downregulated (p < .05). chTLR1a, chTLR1b, chTLR2b and chTLR4 peaked at 36 h post-infection, chTLR3, chTLR5 and chTLR15 peaked at 72 h post-infection and chTLR21 expression was highest among chTLRs, peaking at 48 h post-infection (p < 0.05). For HDPs, cathelicidin (CATH) 1 to 3 and B1 peaked at 48 h post-infection, liver-expressed antimicrobial peptide 2 peaked at 96 h post-infection, and CATH 2 expression was highest among HDPs. CATH2 and CATH3 were markedly upregulated at 3 h post-infection (p < .05). The results provide insight into innate immune molecules during E. tenella infection in chicken, and indicate that innate immune responses may mediate resistance to chicken coccidiosis.

Improving Photocleavage Efficiency of Photocleavable Protein for Antimicrobial Peptide Histatin 1 Expression.

Antimicrobial peptides (AMPs) are promising alternative agents for antibiotics to overcome antibiotic resistance problems. But, it is difficult to produce large-scale antimicrobial research due to the toxicity towards expression hosts or degradation by peptidases in the host. Therefore, heterologous recombinant expression of antimicrobial peptides has always been a challenging issue. To overcome toxicity to the expression host and low expression level, a new photocleavable protein fusion expression method for antimicrobial peptides is provided.3 Methods: Through directed evolution and high throughput screening, a photocleavable protein mutant R6-2-6-4 with a higher photocleavage efficiency was obtained. The DNA coding sequence of antimicrobial peptide Histatin 1 was fused within the sequence of R6-2-6-4 gene. The fusion gene was successfully expressed in Escherichia coli expression system. Antimicrobial peptide Histatin 1 could be successfully expressed and purified by fusing within PhoCl mutant R6-2-6-4. The antimicrobial activity was rarely affected, and the MIC value was 33 ug/mL, which was basically equivalent to 32 ug/mL of the chemically synthesized Histatin 1. After amplification in a 5 L fermenter, the expression of PhoCl mutant (R6-2-6-4)-Histatin1 improved up to 87.6 mg/L in fermenter, and Histatin1 obtained by photocleavage also could up to 11 mg/L. The prepared Histatin1 powder remained stable when stored at 4oC for up to 4 months without any degradation. In addition, the expression and photocleavage of β -Defensin105 and Lysostaphin verified the certain universality of the PhoCl mutant fusion expression system. Antimicrobial peptides Histatin 1, β -Defensin 105 and Lysostaphin were successfully expressed and purified by photocleavable protein mutant. This may provide a novel strategy to express and purify antimicrobial peptides in the Escherichia coli expression system.

Proteome and Peptidome Changes and Zn Concentration in Chicken after In Ovo Stimulation with a Multi-Strain Probiotic and Zn-Gly Chelate: Preliminary Research.

The aim of the study was to determine differences in the proteome and peptidome and zinc concentrations in the serum and tissues of chickens supplemented with a multi-strain probiotic and/or zinc glycine chelate in ovo. A total of 1400 fertilized broiler eggs (Ross × Ross 708) were divided into four groups: a control and experimental groups injected with a multi-strain probiotic, with zinc glycine chelate, and with the multi-strain probiotic and zinc glycine chelate. The proteome and peptidome were analyzed using SDS-PAGE and MALDI-TOF MS, and the zinc concentration was determined by flame atomic absorption spectrometry. We showed that in ovo supplementation with zinc glycine chelate increased the Zn concentration in the serum and yolk sac at 12 h post-hatch. The results of SDS-PAGE and western blot confirmed the presence of Cu/Zn SOD in the liver and in the small and large intestines at 12 h and at 7 days after hatching in all groups. Analysis of the MALDI-TOF MS spectra of chicken tissues showed in all experimental groups the expression of proteins and peptides that regulate immune response, metabolic processes, growth, development, and reproduction.

BmPGPR-L4 is a negative regulator of the humoral immune response in the silkworm Bombyx mori.

Toll, immune deficiency and prophenoloxidase cascade represent vital immune signaling pathways in insects. Peptidoglycan recognition proteins (PGRPs) are innate immune receptors that activate and regulate the immune signaling pathways. Previously, we reported that BmPGPR-L4 was induced in the silkworm Bombyx mori larvae by bacteria and peptidoglycan challenges. Here, we focused on the function of BmPGRP-L4 in regulating the expression of antimicrobial peptides (AMPs). The hemolymph from BmPGRP-L4-silenced larvae exhibited an enhanced inhibitory effect on the growth of Escherichia coli, either by growth curve or inhibitory zone experiments. Coincidentally, most of the AMP genes were upregulated after RNAi of BmPGRP-L4. Oral administration of heat-inactivated E. coli and Staphylococcus aureus after RNAi of BmPGRP-L4 resulted in the increased expression of BmPGRP-L4 in different tissues of the silkworm larvae, revealing an auto-regulatory mechanism. By contrast, the expression of most AMP genes was downregulated by oral bacterial administration after RNAi of BmPGRP-L4. The above results demonstrate that BmPGRP-L4 recognizes bacterial pathogen-associated molecular patterns and negatively regulates AMP expression to achieve immunological homeostasis. As a negative regulator, BmPGPR-L4 is proposed to be involved in the feedback regulation of the immune signaling pathways of the silkworm to prevent excessive activation of the immune response.

Role of tear size and tendon degeneration for development of pain in rat models of rotator cuff tear

BackgroundRotator cuff tear (RCT) is a frequent etiology of shoulder pain and disability; however, the triggers for the onset and aggravation of pain remain obscure. In this study, we established novel rat RCT models to examine the impact of tear size and tendon degeneration on pain. MethodsFifty-five adult male Sprague-Dawley rats were allocated into 4 study groups: large tear (L group, n=10); small tear (S group, n=15); small tear with scratching (S+ group n=15); sham surgery (sham group, n=15). Pain-related behaviors were evaluated by weight distribution of forelimbs during a 5-minute free gait using a dynamic weight-bearing apparatus at 2, 4, 6 and 8 weeks. Calcitonin gene-related peptide (CGRP) expressions in ipsilateral dorsal root ganglion (DRG) neurons of C4/5/6 were evaluated at 4 and 8 weeks. The area of scar tissues around the torn tendon, infiltration of inflammatory cells, and severity of tendon degeneration (modified Bonar score) were histologically assessed at 4 and 8 weeks. Additionally, enzyme-linked immunosorbent assay (ELISA) was conducted to evaluate the levels of cyclooxygenase-2 (COX-2) and nerve growth factor (NGF) expression in torn tendons and surrounding tissues at 4 weeks. ResultsThe weight distribution ratio (ipsilateral /contralateral side) was significantly decreased in the L and S+ group compared with its baseline and sham group (P<0.05), but the S group showed no significant difference compared with the Sham. The ratio of CGRP-immunoreactive neurons in the DRGs was significantly higher in the L and S+ groups than in the S and sham groups. The histological assessment indicated that scar tissue formation was more extensive in the L group than in the S and S+ groups. Still, there was no significant difference between the S and S+ groups. The Modified Bonar Score was considerably higher in the S+ group than in the S group. Furthermore, ELISA analysis demonstrated no significant disparity in COX-2 levels between the groups; however, NGF levels were substantially higher in the S+ group than in the S and sham groups. ConclusionThe present study provides compelling evidence that large RCT is strongly associated with heightened pain severity in a rat mode. Nevertheless, even a small tear can significantly aggravate pain when the torn tendon is degenerated. CGRP upregulation driven by peripheral NGF possibly played a pivotal role in the genesis and exacerbation of pain in small RCT.

The effect of reducing dietary energy on performance, intestinal morphology and intestinal peptide and amino acid transporters in broiler chicks

AbstractBackgroundPrevious research has investigated the impact of different factors such as gender and age of birds, protein and amino acid levels, protein origin and the physical form of the diet, on the mRNA expression of intestinal peptides and amino acid transporters. Nevertheless, there have been no attempts to examine the impact of dietary energy density on the mRNA abundance of intestinal amino acid and peptide transporters in humans or animals. This is the first reported case in both humans and animals.ObjectivesThis experiment aimed to evaluate the influence of two levels of metabolizable energy ([ME]; 2950 and 2850 kcal ME/kg diet) on performance and jejunal morphology and mRNA expression of amino acid (B0AT, b0,+AT, CAT1 and y+LAT1) and peptide (PepT1) transporters in broiler chickens during the starter period (0–10 days of age).MethodsTwo hundred and seventy day‐old male Ross 308 broiler chickens were randomly assigned to two dietary treatments with nine replicates and fifteen birds in each replicate. At 10 days of age, the outcome variables were measured, which included the assessment of the mRNA abundance of PepT1, b0,+AT, B0AT, y+LAT1 and CAT1 in the jejunal section using real‐time PCR.ResultsThe findings of this study revealed no significant impact of the dietary treatments on feed intake, body weight gain, feed conversion ratio and the jejunal mRNA abundance of PepT1, CAT1 and y+LAT1 (p &gt; 0.05). However, a reduction in dietary ME level from 2950 to 2850 kcal ME/kg diet resulted in a decrease in the mRNA level of B0AT and b0,+AT (p ≤ 0.05). The reduction in dietary energy level did not lead to any significant changes in villus width, villus height, crypt depth, villus surface area and villus height to crypt depth ratio (p &gt; 0.05).ConclusionThe results demonstrated that decreasing dietary energy density may alter the expression of amino acid transporters in the intestine while having no impact on the growth performance and morphometric structure of the intestine.

GROUP 3 INNATE LYMPHOID CELLS RELY ON ER STRESS RESPONSE FOR CYTOKINE PRODUCTION IN IBD

Abstract BACKGROUNDS Group 3 innate lymphoid cells (ILC3s) recently emerged as important regulators and potential drug targets for IBD. However, the response of ILC3s to environmental stimuli during intestinal inflammation remains elusive. IRE1a-XBP1 serves as the regulatory hub of the endoplasmic reticulum stress response that plays a vital role in intestinal inflammation. METHODS We generated conditional knockout Ire1aflo/flox,Rorc-Cre (Ire1aΔRorc) and Rag-/-Ire1aΔRorc mice with Ire1a deleted in ILC3s. Intestinal infections were induced by Citrobacter rodentium and Clostridium difficile. ILC3s-derived cytokines including IL-22 is crucial for host defense in the acute phase of C. rodentium and C. difficile infection. Dextran sodium sulfate (DSS) was given in drinking water to induce acute colitis. We recruited patients with active Crohn’s disease (CD) and collected ileal biopsies during routine colonoscopy before starting ustekinumab, a non-selective anti-IL-23 antibody. Mucosal ILC3s were isolated for analysis of ILC3s by flow cytometry. RESULTS In murine intestinal ILC3s, the activity of IRE1a-XBP1 pathway follows a robust 24h circadian rhythm which parallels that of clock genes and cytokines including IL-22. XBP1s is activated in ILC3s ex vivo by vasoactive intestinal peptide, which was previous shown to orchestrate the circadian expression of IL-22 by ILC3s. IRE1a-XBP1 in intestinal ILC3s is further activated in response to IL-23 and colitis in mice, as well as in inflamed IBD tissues compared to normal tissues from healthy individuals. We further showed that IRE1a-XBP1 activation in stimulated ILC3s requires mitochondrial reactive oxygen species (mtROS) (Fig 1). Using the Ire1aΔRorc mice, we demonstrated that IRE1a-XBP1 is critical for cytokine expression by ILC3s. Ire1aΔRorc mice are highly susceptible to acute C. rodentium and C. difficile infection as well as acute DSS colitis (similar vulnerabilities were found in Rag-/-Ire1aΔRorc mice compared to Rag-/-Ire1aflox/flox littermates). Ire1aΔRorc mice exhibit reduced IL-22 and IL-17A in ILC3s and impaired epithelial barrier function with diminished expression of mucins and antimicrobial peptides. The susceptibilities of Ire1aΔRorc and Rag-/-Ire1aΔRorc mice to colitis were rescued by administration of recombinant IL-22 (Fig 2). Moreover, the frequency of XBP1s+ ILC3s in ileal mucosa from CD patients before initiation of ustekinumab positively correlates with response to therapy. CONCLUSIONS We demonstrate that a non-canonical mtROS-IRE1a-XBP1 pathway augments cytokine production by intestinal ILC3s. Loss of IRE1a-XBP1 in ILC3s impairs the optimal and rhythmic expression of protective cytokines and renders the mice more susceptible to intestinal infections and colitis. We also identify XBP1+ ILC3s as a potential biomarker for predicting responsiveness to anti-IL-23 therapies in IBD.

DOP89 Unfolded protein response controls group 3 innate lymphoid cells in IBD

Abstract Background Group 3 innate lymphoid cells (ILC3s) have recently emerged as important regulators and potential drug targets for IBD. However, the response of ILC3s to environmental stimuli during intestinal inflammation remains elusive. IRE1a-XBP1 serves as the regulatory hub of endoplasmic reticulum stress and the unfolded protein response (UPR) that plays a vital role in intestinal inflammation. Methods We generated conditional knockout Ire1aflo/flox,Rorc-Cre (Ire1aΔRorc) and Rag-/-Ire1aΔRorc mice with Ire1a deleted in ILC3s. Intestinal infections were induced by Citrobacter rodentium and Clostridium difficile. ILC3s-derived cytokines including IL-22 is crucial for host defense in the acute phase of C. rodentium and C. difficile infection. Dextran sodium sulfate (DSS) was given in drinking water to induce acute colitis. We recruited patients with active Crohn’s disease (CD) and collected ileal biopsies during routine colonoscopy before starting ustekinumab, a non-selective anti-IL-23 antibody. Mucosal ILC3s were isolated for analysis of ILC3s by flow cytometry. Results In murine intestinal ILC3s, the activity of IRE1a-XBP1 pathway follows a robust 24h circadian rhythm which parallels that of clock genes and cytokines including IL-22. XBP1s is activated in ILC3s ex vivo by vasoactive intestinal peptide, which was previous shown to orchestrate the circadian expression of IL-22 by ILC3s. IRE1a-XBP1 in intestinal ILC3s is further activated in response to IL-23 and colitis in mice, as well as in inflamed IBD tissues compared to normal tissues from healthy individuals. We further showed that IRE1a-XBP1 activation in stimulated ILC3s requires mitochondrial reactive oxygen species (mtROS) (Fig 1). Using the Ire1aΔRorc mice, we demonstrated that IRE1a-XBP1 is critical for cytokine expression by ILC3s. Ire1aΔRorc mice are highly susceptible to acute C. rodentium and C. difficile infection as well as acute DSS colitis (similar vulnerabilities were found in Rag-/-Ire1aΔRorc mice compared to Rag-/-Ire1aflox/flox littermates). Ire1aΔRorc mice exhibit reduced IL-22 and IL-17A in ILC3s and impaired epithelial barrier function with diminished expression of mucins and antimicrobial peptides. The susceptibilities of Ire1aΔRorc and Rag-/-Ire1aΔRorc mice to colitis were rescued by administration of recombinant IL-22 (Fig 2). Moreover, the frequency of XBP1s+ ILC3s in ileal mucosa from CD patients before initiation of ustekinumab positively correlates with response to therapy. Conclusion We demonstrate that a non-canonical mtROS-IRE1a-XBP1 pathway augments cytokine production by intestinal ILC3s. We also identify XBP1+ ILC3s as a potential biomarker for predicting responsiveness to anti-IL-23 therapies in IBD.

Distribution of vasoactive intestinal peptide (VIP) immunoreactivity in the rat pallial and subpallial amygdala and colocalization with γ-aminobutyric acid (GABA).

The amygdaloid complex, also known as the amygdala, is a heterogeneous group of distinct nuclear and cortical pallial and subpallial structures. The amygdala plays an important role in several complex functions including emotional behavior and learning. The expression of calcium-binding proteins and peptides in GABAergic neurons located in the pallial and subpallial amygdala is not uniform and is sometimes restricted to specific groups of cells. Vasoactive intestinal polypeptide (VIP) is present in specific subpopulations of GABAergic cells in the amygdala. VIP immunoreactivity has been observed in somatodendritic and axonal profiles of the rat basolateral and central amygdala. However, a comprehensive analysis of the distribution of VIP immunoreactivity in the various pallial and subpallial structures is currently lacking. The present study used immunohistochemical and morphometric techniques to analyze the distribution and the neuronal localization of VIP immunoreactivity in the rat pallial and subpallial amygdala. In the pallial amygdala, VIP-IR neurons are local inhibitory interneurons that presumably directly and indirectly regulate the activity of excitatory pyramidal neurons. In the subpallial amygdala, VIP immunoreactivity is expressed in several inhibitory cell types, presumably acting as projection or local interneurons. The distribution of VIP immunoreactivity is non-homogeneous throughout the different areas of the amygdaloid complex, suggesting a distinct influence of this neuropeptide on local neuronal circuits and, consequently, on the cognitive, emotional, behavioral and endocrine activities mediated by the amygdala.

FlgI Is a Sec-Dependent Effector of Candidatus Liberibacter asiaticus That Can Be Blocked by Small Molecules Identified Using a Yeast Screen.

Huanglongbing (HLB) is one of the most devastating diseases of citrus worldwide. The phloem-restricted bacterium Candidatus Liberibacter asiaticus (CLas) is considered to be the main pathogen responsible for HLB. There is currently no effective practical strategy for the control of HLB. Our understanding of how pathogens cause HLB is limited because CLas has not been artificially cultured. In this study, 15 potential virulence factors were predicted from the proteome of CLas through DeepVF and PHI-base searches. One among them, FlgI, was found to inhibit yeast growth when expressed in Saccharomyces cerevisiae. The expression of the signal peptide of FlgI fused with PhoA in Escherichia coli resulted in the discovery that FlgI was a novel Sec-dependent secretory protein. We further found that the carboxyl-terminal HA-tagged FlgI was secreted via outer membrane vesicles in Sinorhizobium meliloti. Fluoresence localization of transient expression FlgI-GFP in Nicotiana benthamiana revealed that FlgI is mainly localized in the cytoplasm, cell periphery, and nuclear periphery of tobacco cells. In addition, our experimental results suggest that FlgI has a strong ability to induce callose deposition and cell necrosis in N. benthamiana. Finally, by screening a large library of compounds in a high-throughput format, we found that cyclosporin A restored the growth of FlgI-expressing yeast. These results confirm that FlgI is a novel Sec-dependent effector, enriching our understanding of CLas pathogenicity and helping to develop new and more effective strategies to manage HLB.

Resveratrol alleviates hyperglycemia-induced cardiomyocyte hypertrophy by maintaining mitochondrial homeostasis via enhancing SIRT1 expression

To investigate whether resveratrol alleviates hyperglycemia-induced cardiomyocyte hypertrophy by enhancing the expression of silent information regulation 2 homolog 1 (SIRT1) to maintain mitochondrial homeostasis. Rat cardiomyocytes H9c2 cells with or without lentivirus-mediated mRNA interference of SIRT1 were cultured in high glucose (HG) and treated with resveratrol for 72 h. The changes in superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, reactive oxygen species (ROS) level, and relative surface of the cells were examined, and the mRNA expressions of atrial natriuretic factor (ANF) and brain natriuretic peptide (BNP) and protein expressions of SIRT1, mitochondrial fusion related proteins optic atrophy protein 1 (OPA1) and mitofusin 2, mitochondrial division related proteins dynamin-related protein 1 (DRP1) and fission protein 1 (FIS1), and mitophagy-related proteins BNIP3L and LC3 were detected using RT-qPCR and Western blotting. HG exposure significantly decreased SOD activity, increased MDA content, ROS production, relative cell surface, and the mRNA expressions of ANF and BNP in the cardiomyocytes; the protein expressions of SIRT1, OPA1, mitofusin 2 and BNIP3L and LC3-Ⅱ/LC3-Ⅰ ratio were all decreased and the protein expressions of DRP1 and FIS1 increased in HG-exposed cells (P<0.01). All these changes in HG-exposed cardiomyocytes were significantly alleviated by treatment with resveratrol (P<0.05). The protective effects of resveratrol against HG exposure in the cardiomyocytes were obviously attenuated by transfection of the cells with si-SIRT1 (P<0.05). Resveratrol inhibits hyperglycemia-induced cardiomyocyte hypertrophy by reducing oxidative stress, the mechanisms of which involve enhancement of SIRT1 protein expression, regulation of mitochondrial fusion and division balance, and promoting BNIP3L-mediated mitophagy to maintain mitochondrial homeostasis in the cells.

Expression of motilin and vasoactive intestinal peptide in the mucosa of the sigmoid colon in patients with diverticular disease of the large intestine and irritable bowel syndrome

Expression of motilin and vasoactive intestinal peptide in the mucosa of the sigmoid colon in patients with diverticular disease of the large intestine and irritable bowel syndrome