Exploration of the core pathway of inflammatory bowel disease complicated with metabolic fatty liver and two-sample Mendelian randomization study of the causal relationships behind the disease.

Background: Inflammatory bowel disease (IBD) is often associated with complex extraintestinal manifestations. The incidence of nonalcoholic fatty liver disease (NAFLD) in IBD populations is increasing yearly. However, the mechanism of interaction between NAFLD and IBD is not clear. Consequently, this study aimed to explore the common genetic characteristics of IBD and NAFLD and identify potential therapeutic targets. Materials and methods: Gene chip datasets for IBD and NAFLD were obtained from the Gene Expression Omnibus (GEO) database. Weighted gene co-expression network analysis (WGCNA) was performed to identify modules in those datasets related to IBD and NAFLD. ClueGO was used for biological analysis of the shared genes between IBD and NAFLD. Based on the Human MicroRNA Disease Database (HMDD), microRNAs (miRNAs) common to NAFLD and IBD were obtained. Potential target genes for the miRNAs were predicted using the miRTarbase, miRDB, and TargetScan databases. Two-sample Mendelian randomization (MR) and two-way MR were used to explore the causal relationship between Interleukin-17 (IL-17) and the risk of IBD and NAFLD using data from GWAS retrieved from an open database. Results: Through WGCNA, gene modules of interest were identified. GO enrichment analysis using ClueGO suggested that the abnormal secretion of chemokines may be a common pathophysiological feature of IBD and NAFLD, and that the IL-17-related pathway may be a common key pathway for the pathological changes that occur in IBD and NAFLD. The core differentially expressed genes (DEGs) in IBD and NAFLD were identified and included COL1A1, LUM, CCL22, CCL2, THBS2, COL1A2, MMP9, and CXCL8. Another cohort was used for validation. Finally, analysis of the miRNAs identified potential therapeutic targets. The MR results suggested that although there was no causal relationship between IBD and NAFLD, there were causal relationships between IL-17 and IBD and NAFLD. Conclusion: We established a comorbid model to explain the potential mechanism of IBD with NAFLD and identified the chemokine-related pathway mediated by cytokine IL-17 as the core pathway in IBD with NAFLD, in which miRNA also plays a role and thus provides potential therapeutic targets.

CgSHIP2 negatively regulates the mRNA expressions of CgIL-17s in response to Vibrio splendidus stimulation in Crassostrea gigas.

SH2 domain containing inositol polyphosphate5-phosphatase-2 (SHIP2) is a member of the 5-phosphatase family, acting as a vital negative regulator of immune response in vertebrates. In the present study, a SHIP2 homologue (designed as CgSHIP2) was identified from Pacific oyster, Crassostrea gigas. There was a SH2 domain, an IPPc domain and a SAM domain in CgSHIP2. The mRNA transcripts of CgSHIP2 were widely expressed in all the tested tissues with the highest expression in haemolymph. The mRNA expressions of CgSHIP2 in haemocytes increased significantly at 6, 12, 48 and 72 h after Vibrio splendidus stimulation. The positive green signals of CgSHIP2 protein were mainly located in cytoplasm of haemocytes. After the expression of CgSHIP2 was inhibited by RNA interference, the mRNA transcripts of interleukin 17s (CgIL-17-1, CgIL-17-2, CgIL-17-3 and CgIL-17-6) in the haemocytes increased significantly at 24 h after V. splendidus stimulation, which were 8.15-fold (p < 0.001), 3.44-fold (p < 0.05), 2.15-fold (p < 0.01) and 4.63-fold (p < 0.05) compared with that in NC-RNAi group, respectively. Obvious branchial swelling and cilium shedding in gills were observed in CgSHIP2-RNAi group at 24 h after V. splendidus stimulation. The results suggested that CgSHIP2 played an important role in controlling inflammatory response induced by bacteria in oysters.

Interleukin 17F Gene Polymorphism as a Potential Protective Factor in the Immunopathology of Ocular Toxoplasmosis.

Ocular toxoplasmosis (OT) is characterised by intraocular inflammation due to Toxoplasma gondii infection. Studies have found that interleukin 17 (IL-17) plays a central role in the pathology of OT. However, nucleotide variability in IL17 and interleukin 17 receptor (IL17R) genes has not been characterised in OT. As cytokine gene polymorphisms may influence the expression of these molecules, the aim of this study was to verify whether IL17A (rs2275913), IL17F (rs763780), IL17RA (rs4819554) and IL17RC (rs708567) polymorphisms are associated with OT in a Brazilian population. This study enrolled 214 patients seropositive for T. gondii (110 with OT and 104 without) and 107 controls. Polymorphisms were identified by PCR-restriction fragment length polymorphism analysis, validated by DNA sequencing with chi-square and multivariate analyses being used to assess possible associations between polymorphisms and OT. Logistic regression under the dominant model revealed a protection factor against OT of the C mutant allele of the IL17F (rs763780) polymorphism. The T/C-C/C genotypes were significantly more common in patients without OT compared to those with OT (p value = 0.0066) and controls (p value = 0.014). Findings from this study suggest that the IL17F polymorphism may have an influence in the immunopathology of OT in Brazilian individuals.

Downregulation of Mirlet7 miRNA family promotes Tc17 differentiation and emphysema via de-repression of RORγt.

Environmental air irritants including nanosized carbon black (nCB) can drive systemic inflammation, promoting chronic obstructive pulmonary disease (COPD) and emphysema development. The let-7 microRNA (Mirlet7 miRNA) family is associated with IL-17-driven T cell inflammation, a canonical signature of lung inflammation. Recent evidence suggests the Mirlet7 family is downregulated in patients with COPD, however, whether this repression conveys a functional consequence on emphysema pathology has not been elucidated. Here, we show that overall expression of the Mirlet7 clusters, Mirlet7b/Mirlet7c2 and Mirlet7a1/Mirlet7f1/Mirlet7d, are reduced in the lungs and T cells of smokers with emphysema as well as in mice with cigarette smoke (CS)- or nCB-elicited emphysema. We demonstrate that loss of the Mirlet7b/Mirlet7c2 cluster in T cells predisposed mice to exaggerated CS- or nCB-elicited emphysema. Furthermore, ablation of the Mirlet7b/Mirlet7c2 cluster enhanced CD8+IL17a+ T cells (Tc17) formation in emphysema development in mice. Additionally, transgenic mice overexpressing Mirlet7g in T cells are resistant to Tc17 and CD4+IL17a+ T cells (Th17) development when exposed to nCB. Mechanistically, our findings reveal the master regulator of Tc17/Th17 differentiation, RAR-related orphan receptor gamma t (RORγt), as a direct target of Mirlet7 in T cells. Overall, our findings shed light on the Mirlet7/RORγt axis with Mirlet7 acting as a molecular brake in the generation of Tc17 cells and suggest a novel therapeutic approach for tempering the augmented IL-17-mediated response in emphysema.

Integrated Epigenetic and Transcriptomic Analysis Identifies Interleukin 17 DNA Methylation Signature of Malignant Peripheral Nerve Sheath Tumor Progression and Metastasis.

PURPOSE: Sarcomas are a complex group of highly aggressive and metastatic tumors with over 100 distinct subtypes. Because of their diversity and rarity, it is challenging to generate multisarcoma signatures that are predictive of patient outcomes. MATERIALS AND METHODS: Here, we identify a DNA methylation signature for progression and metastasis of numerous sarcoma subtypes using multiple epigenetic and genomic patient data sets. Malignant Peripheral Nerve Sheath Tumors (MPNSTs) are highly metastatic sarcomas with frequent loss of the histone methyltransferase, PRC2. Loss of PRC2 is associated with MPNST metastasis and plays a critical noncanonical role in DNA methylation. RESULTS: We found that over 900 5'-C-phosphate-G-3' (CpGs) were hypermethylated in MPNSTs with PRC2 loss. Furthermore, we identified eight differentially methylated CpGs in the IL17D/RD family that correlate with the progression and metastasis of MPNSTs in two independent patient data sets. Similar trends were identified in other sarcoma subtypes, including osteosarcoma, rhabdomyosarcoma, and synovial sarcoma. Analysis of scRNAseq data sets determined that IL17D/RD expression occurs in both the tumor cells and the surrounding stromal populations. CONCLUSION: These results might have broad implications for the clinical management and surveillance of sarcoma.

CHOP-mediated IL-23 overexpression does not drive colitis in experimental spondyloarthritis.

HLA-B27 is a major risk factor for spondyloarthritis (SpA), yet the underlying mechanisms remain unclear. HLA-B27 misfolding-induced IL-23, which is mediated by endoplasmic reticulum (ER) stress has been hypothesized to drive SpA pathogenesis. Expression of HLA-B27 and human ß2m (hß2m) in rats (HLA-B27-Tg) recapitulates key SpA features including gut inflammation. Here we determined whether deleting the transcription factor CHOP (Ddit3-/-), which mediates ER-stress induced IL-23, affects gut inflammation in HLA-B27-Tg animals. ER stress-mediated Il23a overexpression was abolished in CHOP-deficient macrophages. Although CHOP-deficiency also reduced Il23a expression in immune cells isolated from the colon of B27+ rats, Il17a levels were not affected, and gut inflammation was not reduced. Rather, transcriptome analysis revealed increased expression of pro-inflammatory genes, including Il1a, Ifng and Tnf in HLA-B27-Tg colon tissue in the absence of CHOP, which was accompanied by higher histological Z-scores. RNAScope localized Il17a mRNA to the lamina propria of the HLA-B27-Tg rats and revealed similar co-localization with Cd3e (CD3) in the presence and absence of CHOP. This demonstrates that CHOP-deficiency does not improve, but rather exacerbates gut inflammation in HLA-B27-Tg rats, indicating that HLA-B27 is not promoting gut disease through ER stress-induced IL-23. Hence, CHOP may protect rats from more severe HLA-B27-induced gut inflammation.

Genetic association of Interleukin-17A polymorphism in Bangladeshi patients with breast and cervical cancer: a case-control study with functional analysis.

BACKGROUND: Breast and cervical cancer are the two leading cancers in terms of incidence and mortality. Previous studies reported different interleukins, including interleukin-17A (IL-17A) to be responsible for the development and progression of these malignancies. Therefore, we speculated that the variants in this gene might be associated with these cancer developments in Bangladeshi population. For evaluating the hypothesis, we investigated the association of IL-17A rs3748067 polymorphism with the susceptibility of both breast and cervical cancer. METHODS: This case-control study was performed on 156 breast cancer patients, 156 cervical cancer patients, and 156 controls using the tetra-primer amplification refractory mutation system-polymerase chain reaction. The statistical software package SPSS (version 25.0) was applied for analyses. The genetic association was measured by the odds ratio (OR) and 95% confidence intervals (CIs). A statistically significant association was considered when p-value ≤ 0.05. Functional analysis was performed using GEPIA and UALCAN databases. RESULTS: From the calculation of the association of IL-17A rs3748067 with breast cancer, it is found that no genotype or allele showed a statistically significant association (p>0.05). On the other hand, the analysis of IL-17A rs3748067 with cervical cancer demonstrated that CT genotype showed a significant association (CT vs. CC: OR=1.79, p=0.021). In the overdominant model, CT genotype also revealed a statistically significant association with cervical cancer, which is found to be statistically significant (OR=1.84, p=0.015). CONCLUSION: Our study summarizes that rs3748067 polymorphism in the IL-17A gene may be associated with cervical cancer but not breast cancer in Bangladeshi patients. However, we suggest studies in the future with a larger sample size.

Study of lncRNAs expression profile in the response to biological drugs in Psoriatic Arthritis: MEG3 could be a potential genomic biomarker of therapy efficacy.

We aimed to identify an expression profile of lncRNAs potentially related to treatment response in Psoriatic arthritis (PsA) patients, to be used as potential genomic biomarkers predictors of drug treatment effectiveness. In addition, we evaluated a possible association between lncRNAs genetic variants and the response to therapy using the clinical parameter of Disease Activity Index. For the expression study, we collected 48 treated PsA patients, monitoring the treatment response for 12 months. We initially used PCR Array and, then, we validated the results with qRT-PCR. We also retrospectively genotyped 163 treated PsA patients. Firstly, we observed a significant difference in the expression level between Responder and non-Responder patients, of 4 lncRNAs in the group of PsA patients treated with TNFi and of 3 lncRNAs in the group of patients treated with IL17i. Then, we confirmed a significant decrease of MEG3 expression in non-Responder patients compared to Responders, also considering separately the single groups of patients treated with TNFi and IL17i. In addition, our results seem to highlight a potential dose-dependent effect of rs941576 (MEG3) variant allele on Disease Activity Index. Our study suggests a possible role of the lncRNA MEG3 in the treatment response to biological drugs.

Effect of ADSCs on Th17/Treg and T-bet/GATA-3 in model mice with primary immune thrombocytopenia.

We aimed to observe the effects of adipose-derived mesenchymal stem cells (ADSCs) on T helper 17 (Th17)/regulatory T cells (Treg) and T-box transcription factor (T-bet)/GATA-binding protein 3 (GATA-3) in model mice with primary immune thrombocytopenia (ITP). 32 BALB/C mice were selected. ADSCs were isolated from 2 mice and cultured. The other 30 mice were randomly divided into the normal control group, the ITP model control group, and the ITP experimental group. Platelet count (PLT), Th17/Treg cells, related serum cytokines [interleukin-6 (IL-6), IL-17A, IL-10, and transforming growth factor ß1 (TGF-ß1)], T-bet and GATA-3 mRNA levels in peripheral blood mononuclear cells (PBMCs) in the 3 groups were detected. PLT and Treg in the ITP experimental group were significantly lower than those in the normal control group (P<0.05), but significantly higher than those in the ITP model control group (P<0.05). Th17 and Th17/Treg in the ITP experimental group were significantly higher than those in the normal control group (P<0.05), but significantly lower than those in the ITP model control group (P<0.05). Serum IL-6 and IL-17A levels, and T-bet mRNA levels in the ITP experimental group were significantly higher than those in the normal control group (P<0.05), but significantly lower than those in the ITP model control group (P<0.05). Serum IL-10 and TGF-ß levels, and GATA-3 mRNA levels in the ITP experimental group were significantly lower than those in the normal control group (P<0.05), but significantly higher than those in the ITP model control group (P<0.05). ADSCs can effectively regulate Th17/Treg balance and improve T-bet/GATA-3 mRNA expression levels in ITP model mice.

Exploring the Correlation between Interleukin-17A Promoter Polymorphism at its -197 G/A and Rheumatoid Arthritis: Impact on Disease Severity and Activity.

T helper 17 (Th17) cells have been reported to be the most powerful factor in autoimmune disorder pathogenesis, which points to the Th17 master cytokine, interleukin (IL)-17A, as the crucial mediator. We aimed to determine the impact of IL-17A polymorphism in the -197 G/A promoter region on level of IL-17 and intensity of rheumatoid arthritis (RA) disease symptoms. This case-control study was conducted at the Department of Clinical Rheumatology of Aswan university Hospital and included 35 people suffering RA and 30 volunteer controls, matched for age and sex. Rheumatoid factor (RF), anti-cyclic citrullinated peptide (anti-CCP) antibodies, erythrocyte sedimentation rate (ESR), serum IL-17, and C-reactive protein (CRP) were measured in the RA patient group. Restriction fragment length polymorphism (RFLP) was conducted by polymerase chain reaction (PCR) amplicon obtained by IL-17A -197 G /A primers. Of the 35 RA patients, RF was positive in 33 (94.29%) and anti-CCP antibodies in 25 (71.43%), CRP in 31 (88.57%). Of the 35 RA patients, 5 (14.29%) patients carried the G/G genotype, 18 (51.43%) G/A and 12 (34.29%) A/A. IL-17 serum level was significantly greater in the more active RA (DAS28 >5.1) group than the less active (DAS28 ≤5.1) group. Of the RA patients carrying wild type G/G genotype, 60% had more active disease (DAS 28> 5.1), as compared to those with lower activity (DAS 28 ≤5.1), 40% carried the wild type G/G genotype. In conclusion, the study findings imply that IL-17A gene polymorphism is connected to RA clinical severity rather than with RA susceptibility.

Tumor necrosis factor alpha induced protein 3, interleukin 10, tumor necrosis factor alpha, and interleukin 17 F genes polymorphisms in Algerian patients with rheumatoid arthritis.

BACKGROUND: Rheumatoid arthritis (RA) is a systemic autoimmune disease with chronic inflammation. Its pathogenesis involves immunological, genetic, and environmental factors. We investigate the association between Tumor Necrosis Factor α Protein 3 (TNFAIP3), Interleukin 10 (IL10), Tumor Necrosis Factor α (TNF α), and Interleukin 17 F (IL17F) polymorphisms with susceptibility to RA. METHODS AND RESULTS: 191 patients with RA diagnosed according to the American College of Rheumatology (ACR)/ European League Against Rheumatism (EULAR) classification and 190 healthy subjects were recruited. Rheumatoid factor (RF), anti-citrullinated peptide antibodies (ACPA), and C-reactive protein (CRP) were measured. Genotyping of the polymorphisms was performed by real-time PCR. Analysis of the allelic frequencies of TNFAIP3 showed a positive association OR (95% CI) = 1.46 (1.01-2.09); p = 0.04, but failed to meet the criteria of significance after Bonferroni Correction. The genotypic and allelic distribution of the IL10, IL17F, and TNFα showed no significant difference when comparing the RA group with controls. Furthermore, the genotype codominant model shows a moderate positive association in the presence of ACPA (OR (95% CI) = 2.82 (1.22-6.24); p = 0.01. None of the polymorphisms studied was associated with RF and CRP production. CONCLUSION: Our results show that there is a tendency for the AG genotype of IL10-1082 to be associated with the production of ACPA in patients with RA. None of the variants studied were associated with RA susceptibility in Algerians.

IL-17 induces NSCLC cell migration and invasion by elevating MMP19 gene transcription and expression through the interaction of p300-dependent STAT3-K631 acetylation and its Y705-phosphorylation.

The cancer cell metastasis is a major death reason for patients with non-small cell lung cancer (NSCLC). Although researchers have disclosed that interleukin 17 (IL-17) can increase matrix metalloproteinases (MMPs) induction causing NSCLC cell metastasis, the underlying mechanism remains unclear. In the study, we found that IL-17 receptor A (IL-17RA), p300, p-STAT3, Ack-STAT3, and MMP19 were up-regulated both in NSCLC tissues and NSCLC cells stimulated with IL-17. p300, STAT3 and MMP19 overexpression or knockdown could raise or reduce IL-17-induced p-STAT3, Ack-STAT3 and MMP19 level as well as the cell migration and invasion. Mechanism investigation revealed that STAT3 and p300 bound to the same region (-544 to -389 nt) of MMP19 promoter, and p300 could acetylate STAT3-K631 elevating STAT3 transcriptional activity, p-STAT3 or MMP19 expression and the cell mobility exposed to IL-17. Meanwhile, p300-mediated STAT3-K631 acetylation and its Y705-phosphorylation could interact, synergistically facilitating MMP19 gene transcription and enhancing cell migration and invasion. Besides, the animal experiments exhibited that the nude mice inoculated with NSCLC cells by silencing p300, STAT3 or MMP19 gene plus IL-17 treatment, the nodule number, and MMP19, Ack-STAT3, or p-STAT3 production in the lung metastatic nodules were all alleviated. Collectively, these outcomes uncover that IL-17-triggered NSCLC metastasis involves up-regulating MMP19 expression via the interaction of STAT3-K631 acetylation by p300 and its Y705-phosphorylation, which provides a new mechanistic insight and potential strategy for NSCLC metastasis and therapy.

Extracellular vesicle dynamics in COPD: understanding the role of miR-422a, SPP1 and IL-17 A in smoking-related pathology.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) induced by smoking poses a significant global health challenge. Recent findings highlight the crucial role of extracellular vesicles (EVs) in mediating miRNA regulatory networks across various diseases. This study utilizes the GEO database to uncover distinct expression patterns of miRNAs and mRNAs, offering a comprehensive understanding of the pathogenesis of smoking-induced COPD. This study aims to investigate the mechanisms by which extracellular vesicles (EVs) mediate the molecular network of miR-422a-SPP1 to delay the onset of COPD caused by smoking. METHODS: The smoking-related miRNA chip GSE38974-GPL7723 was obtained from the GEO database, and candidate miRs were retrieved from the Vesiclepedia database. Downstream target genes of the candidate miRs were predicted using mRNA chip GSE38974-GPL4133, TargetScan, miRWalk, and RNA22 databases. This prediction was integrated with COPD-related genes from the GeneCards database, downstream target genes predicted by online databases, and key genes identified in the core module of WGCNA analysis to obtain candidate genes. The candidate genes were subjected to KEGG functional enrichment analysis using the "clusterProfiler" package in R language, and a protein interaction network was constructed. In vitro experiments involved overexpressing miRNA or extracting extracellular vesicles from bronchial epithelial cell-derived exosomes, co-culturing them with myofibroblasts to observe changes in the expression levels of the miR-422a-SPP1-IL-17 A regulatory network, and assessing protein levels of fibroblast differentiation-related factors α-SMA and collagen I using Western blot analysis. RESULTS: The differential gene analysis of chip GSE38974-GPL7723 and the retrieval results from the Vesiclepedia database identified candidate miRs, specifically miR-422a. Subsequently, an intersection was taken among the prediction results from TargetScan, miRWalk, and RNA22 databases, the COPD-related gene retrieval results from GeneCards database, the WGCNA analysis results of chip GSE38974-GPL4133, and the differential gene analysis results. This intersection, combined with KEGG functional enrichment analysis, and protein-protein interaction analysis, led to the final screening of the target gene SPP1 and its upstream regulatory gene miR-422a. KEGG functional enrichment analysis of mRNAs correlated with SPP1 revealed the IL-17 signaling pathway involved. In vitro experiments demonstrated that miR-422a inhibition targets suppressed the expression of SPP1 in myofibroblasts, inhibiting differentiation phenotype. Bronchial epithelial cells, under cigarette smoke extract (CSE) stress, could compensate for myofibroblast differentiation phenotype by altering the content of miR-422a in their Extracellular Vesicles (EVs). CONCLUSION: The differential gene analysis of Chip GSE38974-GPL7723 and the retrieval results from the Vesiclepedia database identified candidate miRs, specifically miR-422a. Further analysis involved the intersection of predictions from TargetScan, miRWalk, and RNA22 databases, gene search on COPD-related genes from the GeneCards database, WGCNA analysis from Chip GSE38974-GPL4133, and differential gene analysis, combined with KEGG functional enrichment analysis and protein interaction analysis. Ultimately, the target gene SPP1 and its upstream regulatory gene miR-422a were selected. KEGG functional enrichment analysis on mRNAs correlated with SPP1 revealed the involvement of the IL-17 signaling pathway. In vitro experiments showed that miR-422a targeted inhibition suppressed the expression of SPP1 in myofibroblast cells, inhibiting differentiation phenotype. Furthermore, bronchial epithelial cells could compensate for myofibroblast differentiation phenotype under cigarette smoke extract (CSE) stress by altering the miR-422a content in their extracellular vesicles (EVs).

Bcat2-Mediated Branched-Chain Amino Acid Catabolism Is Linked to the Aggravated Inflammation in Obese with Psoriasis Mice.

SCOPE: The global prevalence of obesity has significantly increased, presenting a major health challenge. High-fat diet (HFD)-induced obesity is closely related to the disease severity of psoriasis, but the mechanism is not fully understood. METHODS AND RESULTS: The study utilizes the HFD-induced obesity model along with an imiquimod (IMQ)-induced psoriasis-like mouse model (HFD-IMQ) to conduct transcriptomics and metabolomic analyses. HFD-induced obese mice exhibits more severe psoriasis-like lesions compared to normal diet (ND)-IMQ mice. The expression of genes of the IL-17 signaling pathway (IL-17A, IL-17F, S100A9, CCL20, CXCL1) is significantly upregulated, leading to an accumulation of T cells and neutrophils in the skin. Moreover, the study finds that there is an inhibition of the branched-chain amino acids (BCAAs) catabolism pathway, and the key gene branched-chain amino transferase 2 (Bcat2) is significantly downregulated, and the levels of leucine, isoleucine, and valine are elevated in the HFD-IMQ mice. Furthermore, the study finds that the peroxisome proliferator-activated receptor gamma (PPAR γ) is inhibited, while STAT3 activity is promoted in HFD-IMQ mice. CONCLUSION: HFD-induced obesity significantly amplifies IL-17 signaling and exacerbates psoriasis, with a potential role played by Bcat2-mediated BCAAs metabolism. The study suggests that BCAA catabolism and PPAR γ-STAT3 exacerbate inflammation in psoriasis with obesity.

Gastric digestion of the sweet-tasting plant protein thaumatin releases bitter peptides that reduce H. pylori induced pro-inflammatory IL-17A release via the TAS2R16 bitter taste receptor.

About half of the world's population is infected with the bacterium Helicobacter pylori. For colonization, the bacterium neutralizes the low gastric pH and recruits immune cells to the stomach. The immune cells secrete cytokines, i.e., the pro-inflammatory IL-17A, which directly or indirectly damage surface epithelial cells. Since (I) dietary proteins are known to be digested into bitter tasting peptides in the gastric lumen, and (II) bitter tasting compounds have been demonstrated to reduce the release of pro-inflammatory cytokines through functional involvement of bitter taste receptors (TAS2Rs), we hypothesized that the sweet-tasting plant protein thaumatin would be cleaved into anti-inflammatory bitter peptides during gastric digestion. Using immortalized human parietal cells (HGT-1 cells), we demonstrated a bitter taste receptor TAS2R16-dependent reduction of a H. pylori-evoked IL-17A release by up to 89.7 ± 21.9% (p ≤ 0.01). Functional involvement of TAS2R16 was demonstrated by the study of specific antagonists and siRNA knock-down experiments.

The skin circadian clock gene F3 as a potential marker for psoriasis severity and its bidirectional relationship with IL-17 signaling in keratinocytes.

OBJECTIVE: Psoriasis is an immune-mediated skin disease where the IL-17 signaling pathway plays a crucial role in its development. Chronic circadian rhythm disorder in psoriasis pathogenesis is gaining more attention. The relationship between IL and 17 signaling pathway and skin clock genes remains poorly understood. METHODS: GSE121212 with psoriatic lesion and healthy controls was used as the exploration cohort for searching analysis. Datasets GSE54456, GSE13355, GSE14905, GSE117239, GSE51440, and GSE137218 were applied to validation analysis. Single-cell RNA sequencing (scRNA-seq) dataset GSE173706 was used to explore the F3 expression and related pathway activities in single-cell levels. Through intersecting with high-expression DEGs, F3 was selected as the signature skin circadian gene in psoriasis for further investigation. Functional analyses, including correlation analyses, prediction of transcription factors, protein-protein interaction, and single gene GSEA to explore the potential roles of F3. ssGSEA algorithm was performed to uncover the immune-related characteristics of psoriasis. We further explored F3 expression in the specific cell population in scRNA-seq dataset, besides this, AUCell analysis was performed to explore the pathway activities and the results were further compared between the specific cell cluster. Immunohistochemistry experiment, RT-qPCR was used to validate the location and expression of F3, small interfering RNA (siRNA) transfection experiment in HaCaT, and transcriptome sequencing analysis were applied to explore the potential function of F3. RESULTS: F3 was significantly down-regulated in psoriasis and interacted with IL-17 signaling pathway. Low expression of F3 could upregulate the receptor of JAK-STAT signaling, thereby promoting keratinocyte inflammation. CONCLUSION: Our research revealed a bidirectional link between the skin circadian gene F3 and the IL-17 signaling pathway in psoriasis, suggesting that F3 may interact with the IL-17 pathway by activating JAK-STAT within keratinocytes and inducing abnormal intracellular inflammation.

Triptolide Administration Alters Immune Responses to Mitigate Insulin Resistance in Obese States.

Individuals who are overweight or obese are at increased risk of developing prediabetes and type 2 diabetes, yet the direct molecular mechanisms that connect diabetes to obesity are not clear. Chronic, sustained inflammation is considered a strong risk factor in these interactions, directed in part by the short-lived gene expression programs encoding for cytokines and pro-inflammatory mediators. In this study, we show that triptolide administration in the C57BL/6 diet-induced obese mice at up to 10 µg/kg/day for 10 weeks attenuated the development of insulin resistance and diabetes, but not obesity, in these animals. Significant reductions in adipose tissue inflammation and improved insulin sensitivity were observed in the absence of changes in food intake, body weight, body composition, or energy expenditure. Analysis of the core cluster of biomarkers that drives pro-inflammatory responses in the metabolic tissues suggested TNF-α as a critical point that affected the co-development of inflammation and insulin resistance, but also pointed to the putatively protective roles of increased COX-2 and IL-17A signaling in the mediation of these pathophysiological states. Our results show that reduction of diet-induced inflammation confers partial protection against insulin resistance, but not obesity, and suggest the possibility of achieving overweight phenotypes that are accompanied by minimal insulin resistance if inflammation is controlled.

Effects of silencing NLRP3 gene on proliferation of psoriasis-like HaCaT cells and expressions of cytokines.

We aimed to explore the effects of silencing NOD-like receptor protein 3 (NLRP3) on proliferation of psoriasis-like HaCaT cells and expressions of cytokines. HaCaT cells were treated with human keratinocyte growth factor (KGF) and were divided into KGF group, negative control group, NLRP3-RNAi group and control group. Cells proliferation was detected by CCK8, cell clone formation rate was detected by clone formation assay, distribution of cells cycle was detected by flow cytometry, expressions of cyclin B1 (Cyclin B1), cyclin-dependent kinase 2 (CDK2), Ki67 and proliferating cell nuclear antigen (PCNA) proteins were detected by Western blot, and levels of interleukin (IL)-17, IL-23, IL-6 and tumor necrosis factor α (TNF-α) were detected by enzyme-linked immunosorbent assay. Compared with control group, expressions of NLRP3 mRNA and protein, proliferation rate and clonal formation rate were increased in KGF group, percentage of cells in G0/G1 phase was decreased, percentage of cells in S phase was increased, expressions of Cyclin B1, CDK2, Ki67 and PCNA proteins were increased, and levels of IL-17, IL-23, IL-6 and TNF-α were increased. Compared with negative control group, expressions of NLRP3 mRNA and protein, proliferation rate and clonal formation rate were decreased in NLRP3-RNAi group, percentage of cells in G0/G1 phase was increased, percentage of cells in S phase was decreased, expressions of Cyclin B1, CDK2, Ki67 and PCNA proteins were decreased, and levels of IL-17, IL-23, IL-6 and TNF-α were decreased. Silencing NLRP3 gene can inhibit the proliferation of psoriasis-like HaCaT cells, arrest cell cycle, inhibit the expressions of cell proliferation-related proteins and reduce levels of pro-inflammatory factors.

Co-immunization with DNA vaccines encoding yidR and IL-17 augments host immune response against Klebsiella pneumoniae infection in mouse model.

Klebsiella pneumoniae is an important gram-negative bacterium that causes severe respiratory and healthcare-associated infections. Although antibiotic therapy is applied to treat severe infections caused by K. pneumoniae, drug-resistant isolates pose a huge challenge to clinical practices owing to adverse reactions and the mismanagement of antibiotics. Several studies have attempted to develop vaccines against K. pneumoniae, but there are no licensed vaccines available for the control of K. pneumoniae infection. In the current study, we constructed a novel DNA vaccine, pVAX1-YidR, which encodes a highly conserved virulence factor YidR and a recombinant expression plasmid pVAX1-IL-17 encoding Interleukin-17 (IL-17) as a molecular adjuvant. Adaptive immune responses were assessed in immunized mice to compare the immunogenicity of the different vaccine schemes. The results showed that the targeted antigen gene was expressed in HEK293T cells using an immunofluorescence assay. Mice immunized with pVAX1-YidR elicited a high level of antibodies, induced strong cellular immune responses, and protected mice from K. pneumoniae challenge. Notably, co-immunization with pVAX1-YidR and pVAX1-IL-17 significantly augmented host adaptive immune responses and provided better protection against K. pneumoniae infections in vaccinated mice. Our study demonstrates that combined DNA vaccines and molecular adjuvants is a promising strategy to develop efficacious antibacterial vaccines against K. pneumoniae infections.

Knockdown of TOP2A suppresses IL-17 signaling pathway and alleviates the progression of ulcerative colitis.

BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory disease of the colonic mucosa, with a gradually increasing incidence. Therefore, it is necessary to actively seek targets for the treatment of UC. METHODS: Common differentially expressed genes (DEGs) were screened from two microarray data sets related to UC. Protein-protein interaction network was constructed to find the hub genes. The UC mouse model and cell model were induced by dextran sulfate sodium (DSS). The pathological changes of colon tissue were observed by hematoxylin-eosin staining. Immunohistochemistry and immunofluorescence were performed to detect the expressions of Ki67 and Claudin-1. The performance of mice was observed by disease activity index (DAI). The effect of TOP2A on proliferation, inflammation, oxidative stress, and interleukin-17 (IL-17) signaling pathway in UC model was measured by cell counting kit-8, enzyme-linked immunosorbent assay, and western blot. RESULTS: Through bioinformatics analysis, 295 common DEGs were screened, and the hub gene TOP2A was selected. In UC model, there was obvious inflammatory cell infiltration in the colon and less goblet cells, while si-TOP2A lessened it. More Ki67 positive cells and less Claudin-1 positive cells were observed in UC model mice. Furthermore, knockdown of TOP2A increased the body weight and colon length of UC mice, while the DAI was decreased. Through in vivo and in vitro experiments, knockdown of TOP2A also inhibited inflammation and IL-17 signaling pathway, and promoted proliferation in DSS-induced NCM460 cells. CONCLUSION: Knockdown of TOP2A alleviated the progression of UC by suppressing inflammation and inhibited IL-17 signaling pathway.