IL-4 mRNA Expression Research Articles

P0100 Intestinal adaptation in a mouse model of Crohn’s- like ileitis under short bowel conditions

Abstract Background Short bowel syndrome (SBS) is a rare and complex condition that can occur after ileo caecal resection (ICR), which is often performed in Crohn’s disease (CD) patients. The disease outcome depends on the postsurgical anatomy as well as individual risk factors that may impede intestinal adaptation. The objective of this study was to investigate intestinal adaptation following ICR in a CD mouse model. Methods SAMP1/YitFc (SAMP1, n=37) mice with histologically manifest ileitis and parental controls (AKR, n=34) of both sexes were subjected to 40% ICR or transection (sham) at the age of 14-20 weeks. Intestinal continuity was established by end-to-end jejunocolic anastomosis. Clinical data and stool samples were collected for either 7 or 14 days. Histomorphological adaptation and intestinal inflammation were examined by histological evaluation of residual jejunal and colonic sections as well as by analysis of blood parameters and cytokine mRNA expression in mesenteric lymph nodes (MLN). Results This study was the first to examine adaptation in a CD mouse model. At the age of 14 weeks SAMP1 mice exhibited spontaneous ileitis, with characteristics similar to CD (hypertrophy of muscularis, dysplasia of paneth cells, transmural infiltration, villus blunting). Following surgery, SAMP1 mice showed higher mortality after surgery in ICR and sham groups (both 33%) compared to AKR (21% ICR, 0% sham). ICR resulted in the manifestation of SBS, displayed by body weight loss and diarrhea in both strains. SAMP1 mice exhibited a higher food intake and demonstrated less weight loss than AKR mice. However, the level of wellbeing was significantly lower in comparison to AKR after ICR (p<0.0001 d7, d14). Histomorphological adaptation of the remnant jejunum was worse in SAMP1 mice (villus height SAMP1 229 µm vs. AKR 376 µm, p<0.01). Following ICR, SAMP1 mice exhibited normalization of preoperatively increased inflammatory values in the blood (neutropenia, lymphocytosis) and a reduction of Il4 and Infγ mRNA expression in MLN after ICR (p<0.05 SAMP1 vs. AKR). Conclusion The SAMP1/YitFc mouse is a suitable model for investigating the mechanisms of intestinal adaptation under the influence of experimental chronic ileitis. Subsequent research will focus on the alteration of the inflammatory environment and mucus barrier of the remaining bowel following resection in this model.

Methyl 3-Bromo-4,5-dihydroxybenzoate Attenuates Inflammatory Bowel Disease by Regulating TLR/NF-κB Pathways.

Inflammatory bowel disease (IBD) is characterized by uncontrolled, chronic relapsing inflammation in the gastrointestinal tract and has become a global healthcare problem. Here, we aimed to illustrate the anti-inflammatory activity and the underlying mechanism of methyl 3-bromo-4,5-dihydroxybenzoate (MBD), a compound derived from marine organisms, especially in IBD, using a zebrafish model. The results indicated that MBD could inhibit the inflammatory responses induced by CuSO4, tail amputation and LPS in zebrafish. Furthermore, MBD notably inhibited the intestinal migration of immune cells, enhanced the integrity of the gut mucosal barrier and improved intestinal peristalsis function in a zebrafish IBD model induced by trinitro-benzene-sulfonic acid (TNBS). In addition, MBD could inhibit ROS elevation induced by TNBS. Network pharmacology analysis, molecular docking, transcriptomics sequencing and RT-PCR were conducted to investigate the potential mechanism. The results showed that MBD could regulate the TLR/NF-κB pathways by inhibiting the mRNA expression of TNF-α, NF-κB, IL-1, IL-1β, IL6, AP1, IFNγ, IKKβ, MyD88, STAT3, TRAF1, TRAF6, NLRP3, NOD2, TLR3 and TLR4, and promoting the mRNA expression of IL4, IκBα and Bcl-2. In conclusion, these findings indicate that MBD could be a potential candidate for the treatment of IBD.

Pro-inflammatory effects of inhaled Great Salt Lake dust particles

BackgroundClimate change and human activities have caused the drying of marine environments around the world. An example is the Great Salt Lake in Utah, USA which is at a near record low water level. Adverse health effects have been associated with exposure to windblown dust originating from dried lakebed sediments, but mechanistic studies evaluating the health effects of these dusts are limited.ResultsMonitoring data and images highlight the impact of local crustal and Great Salt Lake sediment dusts on the Salt Lake Valley/Wasatch front airshed. Great Salt Lake sediment and derived PM< 3.1 (quasi-PM2.5 or qPM2.5) contained metals/salts, natural and anthropogenic chemicals, and bacteria. Exposure of mice via inhalation and oropharyngeal aspiration caused neutrophilia, increased expression of mRNA for Il6, Cxcl1, Cxcl2, and Muc5ac in the lungs, and increased IL6 and CXCL1 in bronchoalveolar lavage. Inhaled GSLD qPM2.5 caused a greater neutrophilic response than coal fly ash qPM2.5 and was more cytotoxic to human airway epithelial cells (HBEC3-KT) in vitro. Pro-inflammatory biomarker mRNA induction was replicated in vitro using HBEC3-KT and differentiated monocyte-derived (macrophage-like) THP-1 cells. In HBEC3-KT cells, IL6 and IL8 (the human analogue of Cxcl1 and Cxcl2) mRNA induction was attenuated by ethylene glycol-bis(β-aminoethyl ether)-N, N,N′,N’-tetraacetic acid (EGTA) and ruthenium red (RR) co-treatment, and by TRPV1 and TRPV3 antagonists, but less by the Toll-like Receptor-4 (TLR4) inhibitor TAK-242 and deferoxamine. Accordingly, GSLD qPM2.5 activated human TRPV1 as well as other human TRP channels. Dust from the Salton Sea playa (SSD qPM2.5) also stimulated IL6 and IL8 mRNA expression and activated TRPV1 in vitro, but inhibition by TRPV1 and V3 antagonists was dose dependent. Alternatively, responses of THP-1 cells to the Great Salt Lake and Salton Sea dusts were partially mediated by TLR4 as opposed to TRPV1. Finally, “humanized” Trpv1N606D mice exhibited greater neutrophilia than C57Bl/6 mice following GSLD qPM2.5 inhalation.ConclusionsDust from the GSL playa and similar dried lakebeds may affect human respiratory health via activation of TRPV1, TRPV3, TLR4, and oxidative stress.

FcεRI/PLC axis promotes anandamide synthesis and the formation of CB2-GPR55 heteromers, modulating cytokine production in mast cells.

Mast cells (MC) are crucial effectors in immediate allergic reactions. Monomeric IgE sensitizes MC and triggers various signaling responses. FcεRI/IgE/antigen crosslinking induces the release of several mediators, including bioactive lipids, but little is known about endocannabinoids (eCBs) secretion. Here, we studied the effects of IgE-induced sensitization and FcεRI crosslinking on anandamide (AEA) synthesis and release in bone marrow-derived mast cells (BMMC). Our results showed that mIgE induced AEA secretion through phospholipase C activation. Secreted AEA contributed to p38 phosphorylation induced by mIgE sensitization. Prolonged mIgE sensitization promoted the formation of long-lasting CB2-GPR55 heteromers. FcεRI crosslinking also caused AEA production. Notably, CB2 deficiency increased IL-2 and IL-3 cytokine expression in response to FcɛRI crosslinking. CB2 and GPR55 agonists reduced IL-2 and IL-3 mRNA expression caused by FcεRI activation. Our findings suggest that a) IgE binding to FcɛRI and its antigen-dependent activation leads to an AEA-dependent autocrine regulatory loop that contributes to intracellular signaling in MC and that b) CB2 and GPR55 receptors play a critical role in modulating the effector phase of MC activation by specifically regulating cytokine expression.

Down-regulation of interlinked inflammatory signalling cascades by ethanolic extract of Suaeda fruticosa Forssk. ex J.F. Gmel. attenuated in vivo inflammatory and nociceptive responses.

Juice and decoction of leaves of Suaeda fruticosa, a halophytic medicinal plant of Cholistan desert, is traditionally used to treat rheumatism. The current study was carried out to probe into in vivo anti-nociceptive, anti-inflammatory, and anti-arthritic potential of ethanolic extract of the whole plant of S. fruticosa (Et-SF)and its bioactive molecules. GC-MS screening of Et-SF revealed presence ofvarious bioactive compounds including phytol, thymol, n-hexadecanoic acid,farnesol, and 1-heptacosanol. DPPH in vitro radical scavengingassay demonstrated moderate antioxidant potential of Et-SF. Safety evaluation of Et-SF confirmed no lethal effects in female albino rats up to the singleoral dose of 5000mg/kg. In all invivo models, Et-SF was administered in three doses (125, 250, and 500mg/kg) and a single dose of flurbiprofen (FP) (10mg/kg). Et-SF significantly (p < 0.05) attenuated acute inflammation in carrageenan, histamine, and serotonin-induced rat paw oedema models in a time-dependent manner. Et-SF alleviated oedema, restored haematological parameters, and reduced severe pannus formation, inflammatory cell infiltration, and fibrous tissue proliferation inthe paws of CFA-induced arthritic rats.Moreover, treatment with thymol, farnesol and n-hexadecanoic acid alone and in combination also attenuated the arthritic progression in the arthritic rats indicating involvementof these compounds towards anti-arthritic potential of Et-SF. Et-SF and FP significantly (p < 0.05) down-regulated IL-1β, TNF-α, IL-6, NF-κB, and COX-2 mRNA expression, and up-regulated IL-4 and IL-10 mRNA expression in arthritic rats. Hot plate and acetic acid-induced writhing models results indicated the analgesic attributes of Et-SF in mice models. This study suggests that S. fruticosa ethanol extract may regulate the expression ofinflammatory markers involved in nociceptive, inflammatory, and arthritic disorders. Its phytochemicals could target multiple phases of these conditions at cellular and subcellular levels. Further research is needed to confirm this hypothesis.

Nypa fruticans Wurmb Extract Recovered Compromised Immune Status Induced by Forced Swimming in a Mouse Model.

Nypa fruticans Wurmb is known to contain large amounts of polyphenols and flavonoids with antioxidative and anti-inflammatory effects. However, the biological and physiological functions of N. fruticans have not been scientifically investigated. Thus, we investigated the immunomodulatory effect of N. fruticans hot water extract (YSK-N) in mice using an immune compromised model established by forced swimming (FS). Intensive exercise decreased body weight, organ index, and various immunological parameters in FS mice. However, oral administration of YSK-N significantly restored the FS-induced decreases in body, thymus, and spleen weights, as well as the reduction in the numbers of white blood cells and lymphocytes in the whole blood of mice. Additionally, YSK-N increased splenic cell proliferation in the absence and presence of concanavalin A or lipopolysaccharide stimulation in a concentration-dependent manner. Notably, YSK-N enhanced the cytotoxic activity of natural killer cells against YAC-1 tumor cells under immunosuppressive conditions. Furthermore, YSK-N supplementation reverted the FS-induced downregulation in immunoglobulin production and Il2, Il6, Il12, Ifnγ, Gzmb, and Prf1 mRNA expression. Therefore, our observations suggested that YSK-N promotes immune function and has potential as an immunomodulatory agent.

Identification of the Active EPA/AA-Binding Ether-Type Phosphatidylcholine Derived from the Starfish Patiria pectinifera for C2C12 Myotube Growth.

Concerns about nutritional approaches for promoting skeletal muscle mass and function have increased. This study assessed the effects of starfish-derived glycerophospholipids (PLs) (SPL), characterized by unique ether-linked subclasses, alkylacyl (Alk)- and alkenylacyl (Pls)-PL, on skeletal muscle function, focusing on myotube formation in C2C12 myoblasts. SPL was prepared via chloroform/methanol extraction from Patiria pectinifera, followed by silica gel chromatography fractionation. Myoblasts were induced to differentiate with or without SPL treatment. On day 7 of differentiation, 50 μg/mL of SPL treatment increased myotube diameter. The phosphatidylcholine (PC) fraction (SPC) also enhanced myotube growth at 30 μg/mL. LC-MS/MS analysis indicated the most abundant PC molecular species in SPC were Alk- and Pls-PC with eicosapentaenoic acid and arachidonic acid. Treatment with 1-O-hexadecyl-2-arachidonoyl-PC, 1-1(Z)-hexadecenyl-2-arachidonoyl-PC or 1-O-hexadecyl-2-eicosapentaenoyl-PC increased myotube diameter and myokine Il-15 mRNA expression. These results demonstrate a novel functionality of SPC and highlight the role of ether-type PC molecules in muscle function.

SARS-CoV-2 infection causes a decline in renal megalin expression and affects vitamin D metabolism in the kidney of K18-hACE2 mice

Patients with coronavirus disease 2019 (COVID-19) often experience acute kidney injury, linked to disease severity or mortality, along with renal tubular dysfunction and megalin loss in proximal tubules. Megalin plays a crucial role in kidney vitamin D metabolism. However, the impact of megalin loss on vitamin D metabolism during COVID-19 is unclear. This study investigated whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection reduces megalin expression in proximal tubules and its subsequent effect on vitamin D metabolism in mice expressing human angiotensin converting enzyme 2 (K18-hACE2 mice). Histological and immunohistochemical staining analyses revealed glomerular and capillary congestion, and elevated renal neutrophil gelatinase-associated lipocalin levels, indicative of acute kidney injury in K18-hACE2 mice. In SARS-CoV-2-infected mice, immunohistochemical staining revealed suppressed megalin protein levels. Decreased vitamin D receptor (VDR) localization in the nucleus and increased mRNA expression of VDR, CYP27B1, and CYP24A1 were observed by quantitative PCR in SARS-CoV-2-infected mice. Serum vitamin D levels remained similar in infected and vehicle-treated mice, but an increase in tumor necrosis factor-alpha and a decrease in IL-4 mRNA expression were observed in the kidneys of the SARS-CoV-2 group. These findings suggest that megalin loss in SARS-CoV-2 infection may impact the local role of vitamin D in kidney immunomodulation, even when blood vitamin D levels remain unchanged.

Intranasal Trans-Sialidase Vaccine Mitigates Acute and Chronic Pathology in a Preclinical Oral Chagas Disease Model

Chagas disease, caused by Trypanosoma cruzi, leads to severe complications in 30% of infected individuals, including acute myocarditis and chronic fibrosing cardiomyopathy. Despite the significant burden of this disease, there is currently no licensed vaccine available to prevent it. This study aimed to evaluate the mucosal and systemic immunogenicity as well as the prophylactic efficacy of a mucosal vaccine candidate and its impact on both acute and chronic cardiomyopathy. The results showed that the nasal administration of trans-sialidase (TS) plus c-di-AMP (TS+A) vaccine elicited a NALT expression of IFN-γ, IL-17a and IL-4 mRNA as well as a nasal-specific production of IgA. An in vivo challenge with TS also triggered increased proliferation of lymphocytes from the NALT, sentinel cervical lymph node, and spleen. TS+A immunization increased the plasma levels of Th1/Th2/Th17 cytokines and elicited an evident cellular response by which to judge enhanced delayed-type hypersensitivity responses following a TS footpad challenge. After oral infection, TS+A-vaccinated mice showed significantly reduced parasitemia and parasite load in the heart, muscles and intestines, while markers of hepatic and muscle damage as well as clinical manifestations of acute infection were strongly diminished. TS+A also attenuated acute myocarditis and the expression of inflammatory markers in the heart. The protection conferred by TS+A extended into the chronic phase, where it resulted in a clear reduction in chronic myocarditis, fibrosis and functional electrocardiographic abnormalities, associated with a decreased expression of the pro-fibrotic TGF-β. These results revealed that it is possible to develop a mucosal vaccine against T. cruzi based on TS and c-di-AMP that is capable of reducing the development of Chagas cardiomyopathy, the hallmark of Chagas disease.

A network pharmacology and transcriptome analysis of the therapeutic effects of tea tree oil on the lungs of chicks exposed to hydrogen sulfide

This study investigated the use of tea tree oil (TTO) in the treatment of H2S-induced lung injury in chickens, focusing on the detoxification mechanism. H2S can damage the respiratory system and reduce growth performance. TTO can improve immune inflammation and growth performance. The mechanism by which TTO mitigates the harmful effects of H2S on chicken lungs remains unclear. Therefore, the experimental model was established by H2S exposure and TTO addition in drinking water. The 240 one-day-old Roman pink chicks were selected for the experiment. The trial was divided into control group (CON), treatment group (TTG, 0.02 mL/L TTO+H2S) and H2S exposure group (AVG, H2S). There were 4 replicates in each group and the trial lasted for 42 d. The therapeutic effect of TTO on lung injury in chickens were determined by growth performance evaluation, transcription sequencing and network pharmacology analysis. The results showed that in the test's third week, the body weights of the chickens in the CON were higher than those in the AVG and TTG (P < 0.05). Pathological sections showed that TTO alleviated the symptoms of lung inflammation and bleeding caused by ROS. As showed by transcriptional sequencing, the mRNA expression of apoptosis-related genes Caspase-9, BAK-1, BCL-2 and BAX were significantly altered (P < 0.05). Meanwhile, the mRNA expression of inflammation-related genes IL-2, IL-6, and IL-17 were downregulated (P < 0.05). Network pharmacological analysis showed that CA2, CA4, GABRA5 and ADH1C were the key targets of TTO. The TTO treatment significantly altered these targets (P < 0.05). Molecular docking confirmed the strong binding ability between the active component and the targets. This study showed that TTO inhibits H2S-induced oxidative damage to the lungs, thereby improving their health status. This provides a new solution for the prevention of harmful gas in the poultry industry.

Anti-Allergic and Anti-Inflammatory Effects of Lidocaine-Derived Organic Compounds in a House Dust Mite-Induced Allergic Rhinitis Mouse Model.

Allergic rhinitis (AR) is a common chronic disease that significantly impacts the quality of life. Lidocaine is known to have anti-inflammatory and immunomodulatory effects. This study evaluated the effect of lidocaine analogs in a Dermatophagoides pteronyssinus (DP)-induced AR mouse model. An AR model was developed using BALB/c mice via intraperitoneal sensitization with DP and intranasal challenge with DP. One hour before stimulation with DP, lidocaine analogs, EI137 and EI341 (at a dose of 0.5 or 5 ug/g), were administered intranasally. Nasal symptoms and serum total IgE, interleukin (IL)-4, IL-10, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α levels were evaluated. Reverse-transcription polymerase chain reaction was used to determine IL-4, IL-10, and IFN-γ, as well as the expression of their mRNA transcription factors in the sinonasal mucosa. Histologic changes were evaluated using hematoxylin and eosin and periodic acid-Schiff staining. The DP-induced AR mouse model had increased serum levels of total IgE and cytokines. EI137 and EI341 significantly suppressed the levels of total IgE, IL-4, and TNF-α. Intranasal instillation of EI137 and EI341 significantly inhibited IL-4, IL-10, and IFN-γ mRNA expression, as well as inflammatory cells and mucus-producing goblet cells. Lidocaine analogs also suppressed DP-stimulated IL-4, IFN-γ, and IFN-γ production by splenocytes. Intranasal instillation of EI137 and EI341 exhibited anti-allergic and anti-inflammatory effects, influenced by Th1 and Th2 inflammatory cytokines. These lidocaine analogs suppressed DP-induced sinonasal mucosal inflammation, inflammatory cell infiltration, and mucus hypersecretion.

Iridaea cordata lipid extract associated with the rCP01850 protein of C. pseudotuberculosis elicited a Th1 immune response in immunized sheep

Sheep farming contributes to the socioeconomic development of small and medium-scale livestock farmers. However, several factors can hinder successful animal production, as is the case for infectious diseases, such as the one caused by Corynebacterium pseudotuberculosis, known as caseous lymphadenitis (CLA). CLA has >90% prevalence in Brazilian herds and antibiotic treatment is not effective, consequently causing significant economic losses to farmers. Given the above, effective vaccines need to be developed to prevent this disease. This study aimed to evaluate the adjuvant activity of the lipid extract from the macroalgae Iridaea cordata as a candidate for developing an effective vaccine formulation. For such, four groups of six sheep each were inoculated with sterile 0.9% saline solution (G1), rCP01850 (G2), rCP01850 + I. cordata (G3), and rCP01850 + saponin (G4). Each sheep received two vaccine doses 30 days apart. Total IgG production levels significantly increased in experimental groups G3 and G4 on days 30, 60, and 90. On day 90, G3 showed higher total IgG production (p < 0.05) when compared to G4. When analyzing cytokine production, G3 was the only experimental group with significantly increased IFN-γ, IL-12, TNF-α, and IL-10 mRNA expression levels. Our results show the vaccine formulation containing rCP01850 adjuvanted with the I. cordata lipid extract elicited a Th1 immune response in sheep, indicating I. cordata lipid extract may be a promising adjuvant for developing an effective vaccine against infection caused by C. pseudotuberculosis.

Impaired Coordination of the Ciliary Movement in Patients with Chronic Rhinosinusitis with Nasal Polyps: The Role of Decreased Planar Cell Polarity Protein Expression

The planar cell polarity (PCP) of epithelial ciliated cells is essential for effective mucociliary clearance (MCC) in the sinonasal mucosa. We hypothesize that MCC coordination is impaired in nasal polyp (NP) mucosae due to the suppressed expression of a series of CPLANE (ciliogenesis and planar cell polarity effector) complex proteins in chronic rhinosinusitis (CRS) patients. To investigate this hypothesis, we subjected sinonasal mucosal samples to live video recording to measure mucociliary transport velocity (MCTV) and scanning electron microscopy to evaluate surface morphology. The expression and distribution of a panel of PCP proteins, e.g., WDPCP and FUZ, were investigated in relation to inflammatory cytokine levels and clinical features. The mean MCTV of NP mucosae was significantly lower than that of the inferior turbinate mucosae. The CRS group with NPs (CRSwNP group) (n = 28) showed increased expression of IL-13 and CCL26 mRNA compared to CRS patients without NPs (n = 25) and controls (n = 30). WDPCP and FUZ mRNA levels were significantly decreased in NP mucosae compared to ethmoid sinus mucosae in CRSwNP patients. WDPCP protein distribution was reduced in the cytoplasmic region of ciliated cells in CRSwNP patients. We conclude that suppression of WDPCP in ciliated cells is responsible for the impaired MCC of nasal polyps with type-2 inflammation. This mechanism might explain the decreased clearance and the potential for worsening symptoms of CRSwNP.

Baicalin attenuates PD-1/PD-L1 axis-induced immunosuppression in piglets challenged with Glaesserella parasuis by inhibiting the PI3K/Akt/mTOR and RAS/MEK/ERK signalling pathways

Infection of piglets with Glaesserella parasuis (G. parasuis) induces host immunosuppression. However, the mechanism underlying the immunosuppression of piglets remains unclear. Activation of the PD-1/PD-L1 axis has been shown to trigger host immunosuppression. Baicalin possesses anti-inflammatory and immunomodulatory functions. However, whether baicalin inhibits PD-1/PD-L1 activation and thus alleviates host immunosuppression has not been investigated. In this study, the effect of baicalin on the attenuation of piglet immunosuppression induced by G. parasuis was evaluated. Seventy piglets were randomly divided into the control group, infection group, levamisole group, BMS-1 group, 25 mg/kg baicalin group, 50 mg/kg baicalin group and 100 mg/kg baicalin group. Following pretreatment with levamisole, BMS-1 or baicalin, the piglets were challenged with 1 × 108 CFU of G. parasuis. Our results showed that baicalin, levamisole and BMS-1 modified routine blood indicators and biochemical parameters; downregulated IL-1β, IL-10, IL-18, TNF-α and IFN-γ mRNA expression; and upregulated IL-2 and IL-8 mRNA expression in blood. Baicalin, levamisole and BMS-1 increased the proportions of CD3+ T cells, CD3+CD4+ T cells, CD3+CD8+ T cells and CD3–CD21+ B cells in the splenocyte population, increased the proportions of CD3+ T cells, CD3+CD4+ T cells and CD3+CD8+ T cells in the blood, and inhibited PD-1/PD-L1 and TIM-3 activation. Baicalin, levamisole and BMS-1 reduced p-PI3K, p-Akt, and p-mTOR expression, the p-MEK1/2/MEK1/2 and p-ERK1/2/ERK1/2 ratios and increased RAS expression. Baicalin, levamisole and BMS-1 provided substantial protection against G. parasuis challenge and relieved tissue histopathological damage. Our findings might provide new strategies for controlling G. parasuis infection and other immunosuppressive diseases.

Pro-Inflammatory Effects of Inhaled Great Salt Lake Dust Particles.

Climatological shifts and human activities have decimated lakes worldwide. Water in the Great Salt Lake, Utah, USA is at near record lows which has increased risks for exposure to windblown dust from dried lakebed sediments. Formal studies evaluating the health effects of inhaled Great Salt Lake dust (GSLD) have not been performed despite the belief that the dust is harmful. The objectives of this study were to illustrate windblown dust events, assess the impact of inhaled dust on the lungs, and to identify mechanisms that could contribute to the effects of GSLD in the lungs. An animation, hourly particle and meteorological data, and images illustrate the impact of dust events on the Salt Lake Valley/Wasatch front airshed. Great Salt Lake sediment and PM2.5 contained metals, lipopolysaccharides, natural and anthropogenic chemicals, and bacteria. Inhalation and oropharyngeal delivery of PM2.5 triggered neutrophilia and the expression of mRNA for Il6, Cxcl1, Cxcl2, and Muc5ac in mouse lungs, was more potent than coal fly ash (CFA) PM2.5, and more cytotoxic to human airway epithelial cells (HBEC3-KT) in vitro. Induction of IL6 and IL8 was replicated in vitro using HBEC3-KT and THP-1 cells. For HBEC3-KT cells, IL6 induction was variably attenuated by EGTA/ruthenium red, the TLR4 inhibitor TAK-242, and deferoxamine, while IL8 was attenuated by EGTA/ruthenium red. Inhibition of mRNA induction by EGTA/ruthenium red suggested roles for transition metals, calcium, and calcium channels as mediators of the responses. Like CFA, GSLD and a similar dust from the Salton Sea in California, activated human TRPA1, M8, and V1. However, only inhibition of TRPV1, TRPV3, and a combination of both channels impacted cytokine mRNA induction in HBEC3-KT cells. Responses of THP1 cells were partially mediated by TLR4 as opposed to TRP channels and mice expressing a "humanized" form of TRPV1 exhibited greater neutrophilia when exposed to GSLD via inhalation. This study suggests that windblown dust from Great Salt Lake and similar lake sediments could pose a risk to humans via mechanisms including the activation of TRPV1/V3, TLR4, and possibly oxidative stress.

Cytokines and chemokines skin gene expression in correlation with immune cells in blood and severity in equine insect bite hypersensitivity.

Insect bite hypersensitivity (IBH) is the most frequent skin allergy of horses and is highly debilitating, especially in the chronic phase. IBH is caused by IgE-mediated hypersensitivity reactions to culicoides midge bites and an imbalanced immune response that reduces the welfare of affected horses. In the present study, we investigated the pathological mechanisms of IBH, aiming to understand the immune cell modulation in acute allergic skin lesions of IBH horses with the goal of finding possible biomarkers for a diagnostic approach to monitor treatment success. By qPCR, we quantified the gene expression of cytokines, chemokines, and immune receptors in skin punch biopsies of IBH with different severity levels and healthy horses simultaneously in tandem with the analysis of immune cell counts in the blood. Our data show an increase in blood eosinophils, monocytes, and basophils with a concomitant, significant increase in associated cytokine, chemokine, and immune cell receptor mRNA expression levels in the lesional skin of IBH horses. Moreover, IL-5Ra, CCR5, IFN-γ, and IL-31Ra were strongly associated with IBH severity, while IL-31 and IL-33 were rather associated with a milder form of IBH. In addition, our data show a strong correlation of basophil cell count in blood with IL-31Ra, IL-5, IL-5Ra, IFN-γ, HRH2, HRH4, CCR3, CCR5, IL-12b, IL-10, IL-1β, and CCL26 mRNA expression in skin punch biopsies of IBH horses. In summary, several cytokines and chemokines have been found to be associated with disease severity, hence contributing to IBH pathology. These molecules can be used as potential biomarkers to monitor the onset and progression of the disease or even to evaluate and monitor the efficacy of new therapeutic treatments for IBH skin allergy. To our knowledge, this is the first study that investigated immune cells together with a large set of genes related to their biological function, including correlation to disease severity, in a large cohort of healthy and IBH horses.

Maresin 1 alleviates neuroinflammation and cognitive decline in a mouse model of cecal ligation and puncture.

Inflammation in the central nervous system plays a crucial role in the occurrence and development of sepsis-associated encephalopathy. This study aims to explore the effects of maresin 1 (MaR1), an anti-inflammatory and pro-resolving lipid mediator, on sepsis-induced neuroinflammation and cognitive impairment. Mice were randomly assigned to 4 groups: A sham group (sham operation+vehicle), a cecal ligation and puncture (CLP) group (CLP operation+vehicle), a MaR1-LD group (CLP operation+1 ng MaR1), and a MaR1-HD group (CLP operation+10 ng MaR1). MaR1 or vehicle was intraperitoneally administered starting 1 h before CLP operation, then every other day for 7 days. Survival rates were monitored, and serum inflammatory cytokines [tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β, and IL-6] were measured 24 h after operation using enzyme-linked immunosorbent assay (ELISA). Cognitive function was assessed 7 days after operation using the Morris water maze (MWM) test and novel object recognition (NOR) task. The mRNA expression of TNF-α, IL-1β, IL-6, inducible nitric oxide synthase (iNOS), IL-4, IL-10, and arginase 1 (Arg1) in cortical and hippocampal tissues was determined by real-time reverse transcription PCR (RT-PCR). Western blotting was used to determine the protein expression of iNOS, Arg1, signal transducer and activator of transcription 6 (STAT6), peroxisome proliferator-activated receptor gamma (PPARγ), and phosphorylated STAT6 (p-STAT6) in hippocampal tissue. Microglia activation was visualized via immunofluorescence. Mice were also treated with the PPARγ antagonist GW9662 to confirm the involvement of this pathway in MaR1's effects. CLP increased serum levels of TNF-α, IL-1β, and IL-6, and reduced body weight and survival rates (all P<0.05). Both 1 ng and 10 ng doses of MaR1 significantly reduced serum TNF-α, IL-1β, and IL-6 levels, improved body weight, and increased survival rates (all P<0.05). No significant difference in efficacy was observed between the 2 doses (all P>0.05). MWM test and NOR task indicated that CLP impaired spatial learning, which MaR1 mitigated. However, GW9662 partially reversed MaR1's protective effects. Real-time RT-PCR results demonstrated that, compared to the sham group, mRNA expression of TNF-α, IL-1β, and iNOS significantly increased in hippocampal tissues following CLP (all P<0.05), while IL-4, IL-10, and Arg1 showed a slight decrease, though the differences were not statistically significant (all P>0.05). Compared to the CLP group, both 1 ng and 10 ng MaR1 decreased TNF-α, IL-1β, and iNOS mRNA expression in hippocampal tissues and increased IL-4, IL-10, and Arg1 mRNA expression (all P<0.05). Immunofluorescence results indicated a significant increase in Iba1-positive microglia in the hippocampus after CLP compared to the sham group (P<0.05). Administration of 1 ng and 10 ng MaR1 reduced the percentage area of Iba1-positive cells in the hippocampus compared to the CLP group (both P<0.05). Western blotting results showed that, compared to the CLP group, both 1 ng and 10 ng MaR1 down-regulated the iNOS expression, while up-regulated the expression of Arg1, PPARγ, and p-STAT6 (all P<0.05). However, the inclusion of GW9662 counteracted the MaR1-induced upregulation of Arg1 and PPARγ compared to the MaR1-LD group (all P<0.05). MaR1 inhibits the classical activation of hippocampal microglia, promotes alternative activation, reduces sepsis-induced neuroinflammation, and improves cognitive decline.

Chronic skin damage induces small intestinal damage via IL-13-induced apoptosis.

The gut-skin axis has recently been widely recognized, and both the gut and skin have been found to affect each other through a bidirectional connection; however, the precise mechanisms remain to be elucidated. Therefore, we aimed to investigate the effects of chronic skin damage (CSD) on mouse intestines. Following the CSD model, 4% sodium dodecyl sulfate was applied to the back-shaved murine skin six times for 2 weeks after tape stripping. The small and large intestines were analyzed histologically and immunologically, respectively. Intestinal permeability was measured using fluorescein isothiocyanate-conjugated-dextran. The role of interleukin-13 (IL-13) in the ileum was investigated using an anti-IL-13 antibody. Apoptotic intestinal cells were analyzed using TUNEL staining. Villus atrophy was observed in the small intestine in the CSD model, along with increased permeability. Mast cells, but not T cells, eosinophils, or innate lymph cell-2, were increased in the intestinal mucosa. However, no significant changes were observed in the large intestine. mRNA expression of IL-13 was increased only in the ileum of the CSD model. Apoptotic intestinal epithelial cells were significantly increased in the ileum of the CSD model. Administration of an anti-IL-13 antibody ameliorated the intestinal damage caused by CSD, along with decreased apoptotic cells and mast cell infiltration. Skin damage causes morphological changes in the small intestine, accompanied by increased intestinal permeability, possibly through the IL-13-induced apoptosis of mast cells in the epithelium. Surfactant-mediated mechanical skin damage can cause a leaky gut.

Inhibitory effects of compounds isolated from Geranium wilfordii on IL-4 production and β-hexosaminidase release in RBL-2H3 cells

This study aimed to investigate the anti-allergic activity of compounds isolated from Geranium wilfordii Maxim. and to suggest potential therapeutic agents for allergies. Nine compounds were isolated from an ethanolic G. wilfordii extract using chromatographic methods and identified chemically and by spectroscopic analysis. These compounds were identified using reported literature data as brevifolin carboxylic acid (1), chlorogenic acid (2), corilagin (3), ellagic acid (4), geraniol (5), kaempferol 3-O-dirhamnoside (6), kaempferol 3-O-neohesperidoside (7), protocatechuic acid (8), and gallic acid (9). All nine identified compounds were assessed for including IL-4 mRNA expression and β-hexosaminidase release in RBL-2H3 cells stimulated with PMA/ionomycin or IgE + DNP-BSA. IL-4 gene expression assay showed that corilagin (3) potently inhibited IL-4 production, and β-hexosaminidase release assay showed that protocatechuic acid (8) markedly reduced histamine release. The study shows that of the nine compounds isolated from G. wilfordii, corilagin (3), and protocatechuic acid (8) are potential treatments for allergy-related diseases.

The stimulation of TH2 cells results in increased IL-5 and IL-13 production via the H4 receptor.

Atopic dermatitis (AD) is a chronic inflammatory skin disease resulting in decreased quality of life. Histamine and specifically the H4 receptor play a key role in the inflammatory process in AD and serve as targets for novel therapeutic approaches. In the present study we aimed to elucidate the immunopathological mechanisms with which the H4 receptor impacts TH2 cells and contributes to AD pathophysiology. Total CD4+ T cells obtained from healthy or AD individuals and invitro differentiated TH2 cells were cultured under different conditions and the mRNA expression or protein production of target molecules were determined using quantitative real-time PCR and ELISA. H4 receptor mRNA expression was upregulated concentration dependent upon IL-4 stimulation in invitro differentiated TH2 cells progressively during the differentiation. Transcriptomic analysis of invitro differentiated TH2 versus TH1 cells revealed that the H4 receptor among other genes represents one of the highly upregulated genes in TH2 cells. Most importantly, increased amounts of IL-5 and IL-13 mRNA expression were detected in invitro differentiated TH2 cells as well as protein secretion in the presence of histamine or of the H4 receptor-selective-agonist when compared to the untreated control. We show for the first time an H4 receptor dependent upregulation of the pro-inflammatory cytokines IL-5 and IL-13 in human TH2 cells by histamine. This suggests that the blockade of the H4 receptor may lead to downregulation of these cytokines and amelioration of AD symptoms as reported in first clinical studies.