Progressive Inflammatory Disease Research Articles

Geraniin Alleviates Inflammation in Caco-2 Cells and Dextran Sulfate Sodium-Induced Colitis Mice by Targeting IL-1β.

IL-1β is an important cytokine implicated in the progression of inflammatory bowel disease (IBD) and intestinal barrier dysfunction. The polyphenolic compound, geraniin, possesses bioactive properties, such as antitumor, antioxidant, anti-inflammatory, antihypertensive, and antiviral activities; however, its IL-1β-targeted anticolitis activity remains unclear. Here, we evaluated the inhibitory effect of geraniin in IL-1β-stimulated Caco-2 cells and a dextran sulfate sodium (DSS)-induced colitis mouse model. Geraniin blocked the interaction between IL-1β and IL-1R by directly binding to IL-1β and inhibited the IL-1β activity. It suppressed IL-1β-induced intestinal tight junction damage in human Caco-2 cells by inhibiting IL-1β-mediated MAPK, NF-kB, and MLC activation. Moreover, geraniin administration effectively reduced colitis symptoms and attenuated intestinal barrier injury in mice by suppressing elevated intestinal permeability and restoring tight junction protein expression through the inhibition of MAPK, NF-kB, and MLC activation. Thus, geraniin exhibits anti-IL-1β activity and anticolitis effect by hindering the IL-1β and IL-1R interaction and may be a promising therapeutic anti-IL-1β agent for IBD treatment.

The Role of H3K27me3-Mediated Th17 Differentiation in Ankylosing Spondylitis.

Ankylosing spondylitis (AS) is a common chronic progressive inflammatory autoimmune disease. T helper 17 (Th17) cells are the major effector cells mediating AS inflammation. Histone 3 Lys 27 trimethylation (H3K27me3) is an inhibitory histone modification that silences gene transcription and plays an important role in Th17 differentiation. The objective of this study was to investigate the expression of H3K27me3 in patients with AS and to explore its epigenetic regulation mechanism of Th17 differentiation during AS inflammation. We collected serum samples from 45 patients with AS at various stages and 10 healthy controls to measure their Interleukin-17 (IL-17) levels using ELISA. A quantitative polymerase chain reaction was used to quantify the mRNA levels of RORc and the signaling molecules of the JAK2/STAT3 pathway, JMJD3, and EZH2. Additionally, Western blot analysis was performed to quantify the protein levels of H3K27me3, RORγt, JAK2, STAT3, JMJD3, and EZH2 in cell protein extracts. The results showed that H3K27me3 expression in peripheral blood mononuclear cells (PBMCs) was significantly lower in patients with active AS compared to both the normal control groups and those with stable AS. Moreover, a significant negative correlation was observed between H3K27me3 expression and the characteristic transcription factor of Th17 differentiation, RORγt. We also discovered that patients with active AS exhibited significantly higher levels of JMJD3, an inhibitor of H3K27 demethylase, compared to the normal control group and patients with stable AS, while the expression of H3K27 methyltransferase (EZH2) was significantly lower. These findings suggest that H3K27me3 may be a dynamic and important epigenetic modification in AS inflammation, and JMJD3/EZH2 regulates the methylation level of H3K27me3, which may be one of the key regulatory factors in the pathogenesis of AS. These findings contribute to our understanding of the role of epigenetics in AS and may have implications for the development of novel therapeutic strategies for AS.

Open Lumbar Sympathectomy on Buerger’s Disease: A Case Report

Thromboangiitis obliterans known as Buerger's disease is a nonatherosclerotic, progressive inflammatory disease that affects small and medium arteries in the upper and lower extremities. Strong relationship was found between the development of this disease and the patient's history of smoking. We reported a case of 50-year-old male with progressive pain in fingers of right leg with darkened ulcer. Open lumbar sympathectomy is a procedure that is rarely performed nowadays, but progressive pain in buerger’s disease patients can be managed with this procedure. The aim of sympathectomy is to reduce sympathetic response causing vasodilation effect which will reduce rest pain.

Made to order: emergency myelopoiesis and demand-adapted innate immune cell production.

Definitive haematopoiesis is the process by which haematopoietic stem cells, located in the bone marrow, generate all haematopoietic cell lineages in healthy adults. Although highly regulated to maintain a stable output of blood cells in health, the haematopoietic system is capable of extensive remodelling in response to external challenges, prioritizing the production of certain cell types at the expense of others. In this Review, we consider how acute insults, such as infections and cytotoxic drug-induced myeloablation, cause molecular, cellular and metabolic changes in haematopoietic stem and progenitor cells at multiple levels of the haematopoietic hierarchy to drive accelerated production of the mature myeloid cells needed to resolve the initiating insult. Moreover, we discuss how dysregulation or subversion of these emergency myelopoiesis mechanisms contributes to the progression of chronic inflammatory diseases and cancer.

MCC950 attenuates plasma cell mastitis in an MDSC-dependent manner

Plasma cell mastitis (PCM) is a sterile inflammatory condition primarily characterized by periductal inflammation and ductal ectasia. Currently, there is a lack of non-invasive or minimally invasive treatment option other than surgical intervention. The NLRP3 inflammasome has been implicated in the pathogenesis and progression of various inflammatory diseases, however, its involvement in PCM has not yet been reported. In this study, we initially observed the pronounced upregulation of NLRP3 in both human and mouse PCM tissue and elucidated the mechanism underlying the attenuation of PCM through inhibition of NLRP3. We established the PCM murine model and collected samples on day 14, when inflammation reached its peak, for subsequent research purposes. MCC950, an NLRP3 inhibitor, was utilized to effectively ameliorate PCM by significantly reducing plasma cell infiltration in mammary tissue, as well as attenuate the expression of pro-inflammatory cytokines including IL-1β, TNF-α, IL-2, and IL-6. Mechanistically, we observed that MCC950 augmented the function of myeloid-derived suppressor cells (MDSCs), which in turn inhibited the infiltration of plasma cells. Furthermore, it was noted that depleting MDSCs greatly compromised the therapeutic efficacy of MCC950. Collectively, our findings suggest that the administration of MCC950 has the potential to impede the progression of PCM by augmenting MDSCs both numerically and functionally, ultimately treating PCM effectively. This study provides valuable insights into the utilization of pharmacological agents for PCM treatment.

A Comprehensive Review on the Role of Interleukin-40 as a Biomarker for Diagnosing Inflammatory Diseases.

Interleukins are a group of proteins that have a wide range of complex functions and are believed to be involved in several diseases and conditions. In particular, interleukin-40 (IL-40) is a recently identified cytokine associated with B cells that was first introduced by Catalan et al. in 2017. This cytokine has several roles in the body, including functioning in the formation of B cells in the bone marrow, IgA production, and expression in the intestinal microbiome. Moreover, IL-40 appears to be involved in numerous autoimmune and inflammatory conditions, such as rheumatoid arthritis, systemic lupus erythematosus, primary Sjogren's syndrome, ankylosing spondylitis, type 2 diabetes, Graves' disease, and hepatic cell carcinoma. Our understanding of this molecule is quite restricted due to its novelty. However, because of its inflammatory characteristics, there is a high probability that it contributes to a variety of inflammatory disease complications. The aim of the present review is to highlight all available data on the importance of assessing IL-40 levels in human diseases up to now, which could be used as a diagnostic biomarker for the onset or progression of numerous inflammatory diseases.

Cervical Vertebrae Internal Fixation Revision in a Patient with Ankylosing Spondylitis: A Case Report

Ankylosing spondylitis (AS) is a chronic progressive inflammatory disease that affects the sacroiliac joints and surrounding joints. It is a seronegative spondyloarthritis that invades connective tissue. Managing cervical spine fractures in patients with AS is particularly challenging due to the severity of the deformity and the instability of the fracture. Cervical spine fracture combined with spinal cord injury is the leading cause of death and is strongly correlated with in-hospital mortality in patients with ankylosing spondylitis. There have been limited reports on the revision of cervical spine fractures after internal fixation in patients with AS. The case report is about a patient who is a 34-year-old man who underwent emergency surgery at a local hospital for a cervical spine fracture resulting from a car accident. A postoperative review revealed that the anterior internal fixation was detached, leading to a revision surgery being performed according to the patient's actual condition. Unfortunately, the internal fixation became dislodged fol-lowing the initial surgery, exacerbating the patient's condi-tion and leading to the development of pneumonia. In order to prevent the need for revision surgery, it is crucial to carefully evaluate and determine the most suitable surgical approach for patients with cervical spine fractures and spinal cord injury before proceeding with the initial surgery.

Atherosclerotic Plaque Erosion: Mechanisms, Clinical Implications, and potential therapeutic Strategies - a review.

Atherosclerosis is an insidious and progressive inflammatory disease characterized by the formation of lipid-laden plaques within the intima of arterial walls with potentially devastating consequences. While rupture of vulnerable plaques has been extensively studied, a distinct mechanism known as plaque erosion has gained recognition and attention in recent years. Plaque erosion, characterized by the loss of endothelial cell lining in the presence of intact fibrous cap contributes to a significant and growing proportion of acute coronary events. However, despite a heterogenous substrate underlying coronary thrombosis, treatment remains identical. This article provides an overview of atherosclerotic plaque erosion characteristics and its underlying mechanisms, highlights its clinical implications, and discusses potential therapeutic strategies.

Elevated CD169 expressing monocyte/macrophage promotes systemic inflammation and disease progression in cirrhosis.

Systemic inflammation is related to disease progression and prognosis in patients with advanced cirrhosis. However, the mechanisms underlying the initiation of inflammation are still not fully understood. The role of CD169+ monocyte/macrophage in cirrhotic systemic inflammation was undetected. Flow cytometry analysis was used to detect the percentage and phenotypes of CD169+ monocytes as well as their proinflammatory function in patient-derived cirrhotic tissue and blood. Transcriptome differences between CD169+ and CD169- monocytes were also compared. Additionally, a mouse model with specific depletion of CD169+ monocytes/macrophages was utilized to define their role in liver injury and fibrosis. We observed increased CD169 expression in monocytes from cirrhotic patients, which was correlated with inflammatory cytokine production and disease progression. CD169+ monocytes simultaneously highly expressed M1- and M2-like markers and presented immune-activated profiles. We also proved that CD169+ monocytes robustly prevented neutrophil apoptosis. Depletion of CD169+ monocytes/macrophages significantly inhibited inflammation and liver necrosis in acute liver injury, but the spontaneous fibrin resolution after repeated liver injury was impaired. Our results indicate that CD169 defines a subset of inflammation-associated monocyte that correlates with disease development in patients with cirrhosis. This provides a possible therapeutic target for alleviating inflammation and improving survival in cirrhosis.

Neuroinflammation Targeting Pyroptosis: Molecular Mechanisms and Therapeutic Perspectives in Stroke.

Pyroptosis is a recently identified type of pro-inflammatory programmed cell death (PCD) mediated by inflammasomes and nucleotide oligomerization domain-like receptors (NLs) and dependent on members of the caspase family. Pyroptosis has been widely reported to participate in the occurrence and progression of various inflammatory diseases, including stroke, a frequently lethal disease with high prevalence and many complications. To date, there have been no effectively therapeutic strategies and methods for treating stroke. Pyroptosis is thought to be closely related to the occurrence and development of stroke. Understanding inflammatory responses induced by the activation of pyroptosis would be hopeful to provide feasible approaches and strategies. Targeting on molecules in the upstream or downstream of pyroptosis pathway has shown promise in the treatment of stroke. The present review summarizes current research on the characteristics of pyroptosis, the function and pathological phenomena of pyroptosis in stroke, the molecule mechanisms related to inflammatory pathways, and the drugs and other molecules that can affect outcomes after stroke. These findings may help identify possible targets or new strategies for the diagnosis and treatment of stroke.

Natural xanthones as modulators of the Nrf2/ARE signaling pathway and potential gastroprotective agents.

Oxidative stress is implicated in the initiation, pathogenesis, and progression of various gastric inflammatory diseases (GID). The prevalence of these diseases remains a concern along with the increasing risks of adverse effects in current clinical interventions. Hence, new gastroprotective agents capable of inhibiting oxidative stress by modulating cellular defense systems such as the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway are critically needed to address these issues. A candidate to solve the present issue is xanthone, a natural compound that reportedly exerts gastroprotective effects via antioxidant, anti-inflammatory, and cytoprotective mechanisms. Moreover, xanthone derivatives were shown to modulate the Nrf2/ARE signaling pathway to counter oxidative stress in both in vitro and in vivo models. Thirteen natural xanthones have demonstrated the ability to modulate the Nrf2/ARE signaling pathway and have high potential as lead compounds for GID as indicated by their in vivo gastroprotective action-particularly mangiferin (2), α-mangostin (3), and γ-mangostin (4). Further studies on these compounds are recommended to validate the Nrf2 modulatory ability in relation to their gastroprotective action.

Updated epithelial barrier dysfunction in chronic rhinosinusitis: Targeting pathophysiology and treatment response of tight junctions.

Tight junction (TJ) proteins establish a physical barrier between epithelial cells, playing a crucial role in maintaining tissue homeostasis by safeguarding host tissues against pathogens, allergens, antigens, irritants, etc. Recently, an increasing number of studies have demonstrated that abnormal expression of TJs plays an essential role in the development and progression of inflammatory airway diseases, including chronic obstructive pulmonary disease, asthma, allergic rhinitis, and chronic rhinosinusitis (CRS) with or without nasal polyps. Among them, CRS with nasal polyps is a prevalent chronic inflammatory disease that affects the nasal cavity and paranasal sinuses, leading to a poor prognosis and significantly impacting patients' quality of life. Its pathogenesis primarily involves dysfunction of the nasal epithelial barrier, impaired mucociliary clearance, disordered immune response, and excessive tissue remodeling. Numerous studies have elucidated the pivotal role of TJs in both the pathogenesis and response to traditional therapies in CRS. We therefore to review and discuss potential factors contributing to impair and repair of TJs in the nasal epithelium based on their structure, function, and formation process.

CXCR5+TIM-3-PD-1+ stem-like cytotoxic CD8+ T cells: elevated in chronic rhinosinusitis and associated with disease severity.

Chronic rhinosinusitis (CRS) is a chronic inflammatory disease with an autoimmune background. Altered expression levels of T cell immunoglobulin and mucin-domain containing-3 (TIM-3), C-X-C chemokine receptor type 5 (CXCR5), and programmed cell death protein 1 (PD-1) are implicated in the progression of inflammatory and autoimmune diseases. Moreover, CXCR5+TIM-3-PD-1+ stem-like cytotoxic T cells function as memory stem cells during chronic disease processes and retain cytotoxicity-related gene networks. To explore the expressions of CXCR5, TIM-3, and PD-1 on T cells and their correlation with clinical parameters in CRS. Flow cytometry was used to assess the expressions and co-expressions of CXCR5, TIM-3, and PD-1 on T cells in the tissues of the paranasal sinus and peripheral blood of patients with CRS as well as healthy controls. Immunofluorescence was used to assess the co-localization of TIM-3, CXCR5, and PD-1 with T cells. The disease severity of our patients with CRS was evaluated using the Lund-Mackay score. A complete blood count was also performed for the patients with CRS. Expression levels of CXCR5 and PD-1 on T cells were significantly increased in the nasal tissues of patients with CRS. Compared with those in healthy controls, patients with CRS had high percentages of CXCR5+TIM-3-PD-1+ CD8+ and CD4+ T cells in nasal tissues, while no significant difference was observed in peripheral blood levels. Patients with CRS had a higher density of nasal CXCR5+TIM-3-PD-1+ T cells than that in healthy controls. CXCR5+TIM-3-PD-1+ CD8+ T cell levels in the nasal polyps of patients with CRS were negatively correlated with the patients' Lund-Mackay scores. The levels of CXCR5+TIM-3-PD-1+ T cells in nasal tissues were also negatively associated with disease duration and positively associated with the chronic inflammatory state of CRS. The level of CXCR5+TIM-3-PD-1+ stem cell-like T cells, especially CXCR5+TIM-3-PD-1+ CD8+ T cells, is increased in CRS. Therefore, inducing CXCR5+TIM-3-PD-1+ T cell exhaustion may be an effective immunotherapy for CRS.

Tauroursodeoxycholic acid liposome alleviates DSS-induced ulcerative colitis through restoring intestinal barrier and gut microbiota

Ulcerative colitis (UC) is a chronic and progressive inflammatory disease that damages the colonic mucosa and disrupts the intestinal epithelial barrier. The current clinical treatment for UC is mainly chemotherapy, which has the limited effectiveness and severe side effects. It mainly focuses on the treatment of inflammation while neglecting the repair of the intestinal mucosa and the restoration of the microbiota balance. Here, we aimed to address these challenges by using an amphipathic bile acid -tauroursodeoxycholic acid (TUDCA) to replace cholesterol (CHL) in conventional liposomes. We prepared TUDCA/Emodin liposomes by incorporating the hydrophobic drug emodin. The experimental results indicated that TUDCA/Emodin Lip had uniform particle size distribution, good stability, low cytotoxicity, and exhibited good mucus permeability and anti-inflammatory activity in in vitro experiments, and was able to protect cells from oxidative stress. After oral administration, TUDCA/Emodin Lip significantly alleviated the severity of UC. This was evidenced by increased colon length, decreased inflammation and reduced colonic endoplasmic reticulum stress (ERS). Furthermore, TUDCA/Emodin Lip maintained the normal levels of the tight junction proteins Claudin-1 and ZO-1, thereby restoring the integrity of the intestinal barrier. Importantly, TUDCA/Emodin Lip also promoted the ecological restoration of the gut microbiota, increased overall abundance and diversity. Taken together, TUDCA/Emodin Lip can fundamentally restore intestinal homeostasis, this work provides a new, efficient and easily transformable treatment for UC.

Does Chronic Pancreatitis in Growing Pigs Lead to Articular Cartilage Degradation and Alterations in Subchondral Bone?

Chronic pancreatitis (CP), a progressive inflammatory disease, poses diagnostic challenges due to its initially asymptomatic nature. While CP's impact on exocrine and endocrine functions is well-recognized, its potential influence on other body systems, particularly in young individuals, remains underexplored. This study investigates the hypothesis that CP in growing pigs leads to alterations in articular cartilage and subchondral bone, potentially contributing to osteoarthritis (OA) development. Utilizing a pig model of cerulein-induced CP, we examined the structural and compositional changes in subchondral bone, articular cartilage, and synovial fluid. Histological analyses, including Picrosirius Red and Safranin-O staining, were employed alongside immuno-histochemistry and Western blotting techniques. Our findings reveal significant changes in the subchondral bone, including reduced bone volume and alterations in collagen fiber composition. Articular cartilage in CP pigs exhibited decreased proteoglycan content and alterations in key proteins such as MMP-13 and TGF-β1, indicative of early cartilage degradation. These changes suggest a link between CP and musculoskeletal alterations, underscoring the need for further research into CP's systemic effects. Our study provides foundational insights into the relationship between CP and skeletal health, potentially guiding future pediatric healthcare strategies for early CP diagnosis and management.

Sarcoidosis. A review of diagnosis, clinical features and treatment

Introduction: Sarcoidosis is a progressive chronic multisystemic inflammatory disease of unclear pathogenesis, which presents with noncaseating granulomas and is complicated to diagnose due to the variable clinical presentation of patients. Sarcoidosis may attack any organ, but especially the pulmonary, cutaneous, lymphatic, ocular, hepatic and splenic systems. The most frequent presentations are prolonged cough, rash, visual problems, peripheral lymphadenopathy, tiredness, and occasional abnormality of the chest X-ray. The diagnostic evaluation of sarcoidosis is difficult and often involves a combined effort of clinical data and appropriate imaging modalities. Purpose: The purpose of this article is to review the available literature on the epidemiology, clinical manifestations and management of patients with sarcoidosis Materials and method: The available literature in PubMed was reviewed to write the article, using the keywords ,,sarcoidosis”, ,,cardiac sarcoidosis”, ,,pulmonary sarcoidosis” and ,,cutaneous sarcoidosis”. Conclusion: Sarcoidosis is associated with a significant increase in patient mortality, as well as decreased quality of life and physical disability. Efforts to accurately predict disease progression allow for more comprehensive and personalized patient care. As a life threatening disease, sarcoidosis needs to be diagnosed early and treated appropriately.

African American race does not confer an increased risk of clinical events in patients with primary sclerosing cholangitis.

The natural history of primary sclerosing cholangitis (PSC) among African Americans (AA) is not well understood. Transplant-free survival and hepatic decompensation-free survival were assessed using a retrospective research registry from 16 centers throughout North America. Patients with PSC alive without liver transplantation after 2008 were included. Diagnostic delay was defined from the first abnormal liver test to the first abnormal cholangiogram/liver biopsy. Socioeconomic status was imputed by the Zip code. Among 850 patients, 661 (77.8%) were non-Hispanic Whites (NHWs), and 85 (10.0%) were AA. There were no significant differences by race in age at diagnosis, sex, or PSC type. Inflammatory bowel disease was more common in NHWs (75.8% vs. 51.8% p=0.0001). The baseline (median, IQR) Amsterdam-Oxford Model score was lower in NHWs (14.3, 13.4-15.2 vs. 15.1, 14.1-15.7, p=0.002), but Mayo risk score (0.03, -0.8 to 1.1 vs. 0.02, -0.7 to 1.0, p=0.83), Model for End-stage Liver Disease (5.9, 2.8-10.7 vs. 6.4, 2.6-10.4, p=0.95), and cirrhosis (27.4% vs. 27.1%, p=0.95) did not differ. Race was not associated with hepatic decompensation, and after adjusting for clinical variables, neither race nor socioeconomic status was associated with transplant-free survival. Variables independently associated with death/liver transplant (HR, 95% CI) included age at diagnosis (1.04, 1.02-1.06, p<0.0001), total bilirubin (1.06, 1.04-1.08, p<0.0001), and albumin (0.44, 0.33-0.61, p<0.0001). AA race did not affect the performance of prognostic models. AA patients with PSC have a lower rate of inflammatory bowel disease but similar progression to hepatic decompensation and liver transplant/death compared to NHWs.

Effect of Nonsteroidal Anti-inflammatory Drug (NSAID) in Disease Relapse, Progression, and Development of Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis investigated the association between nonsteroidal anti-inflammatory drugs (NSAIDs) and inflammatory bowel disease (IBD). Pooled analysis showed no significant association in disease relapse (OR 0.97; 95% CI 0.70–1.35; p = 0.86) and disease worsening (OR 2.06; 95% CI 0.92–4.57; p = 0.08) of existing IBD in patients receiving NSAID. In patients without prior IBD diagnosis, NSAID medication was significantly associated with risk of new-onset IBD (OR 1.51; 95% CI 1.19–1.92; p = 0.0008). Given the varied effects of NSAIDs on IBD, careful management and consideration of dosage and frequency are essential in IBD patients. Despite these insights, the heterogeneity of study designs and small sample sizes in some cases call for further large-scale research to validate these findings.

IHIBITION OF TRNA QUEUOSINE MODIFICATION CAUSE MITOCHONDRIAL DYSFUNCTION AND APOPTOSIS IN THE INTESTINAL EPITHELIAL CELLS

Abstract BACKGROUND Transfer RNA (tRNA) modifications occur through the action of specific enzymes that recognize and modify the nucleotides within the tRNA molecule. Queuine tRNA-ribosyltransferase catalytic subunit 1 (QTRT1) and QTRT 2 co-localize in mitochondria and form a heterodimeric TGT participating in tRNA Queuosine (tRNA-Q) modification. Our previous study demonstrated that Q-tRNA modification plays a novel role in regulating barrier functions of intestinal epithelial cells. However, the roles of tRNA-Q modifications in the maintenance of intestinal mitochondrial homeostasis and the progression of inflammatory bowel disease (IBD) are still unclear. METHODS We used QTRT1 knockout (KO) mice and cultured cell lines with QTRT1 knockdown (KD) to investigate the impact and mechanism of tRNA-Q modifications in intestinal mitochondrial homeostasis and inflammation. RESULTS Initially, we confirmed QTRT1's mitochondrial localization through immunofluorescence co-localization with Mitotracker staining in QTRT1 KD CaCO2-BBE cells. Then we used flow cytometry MitoSox Red staining and revealed an increase in mitochondrial ROS production in QTRT1 KD cells. Furthermore, we observed heightened mitophagy both in vitro and in the colon of QTRT1KO mice, evident through significantly enhanced fusion of Mtphagy Dye-labeled mitochondria with lysosomes, and altered mitochondrial proteins (Tomm20, LC3, and Cytochrome C) via Western Blotting. Notably, we identified an increase in apoptosis in the QTRT1 KO mice evidenced by the upregulation of phosphorylated PARP, cleaved Caspase 3, and the Bax/BCL-2 ratio in colonic mitochondrial proteins. TUNEL staining corroborated this apoptosis increase specifically in the colon due to the QTRT1 deficiency. CONCLUSIONS Reduced QTRT1 induced dysfunctional mitochondria and Caspase-3 dependent apoptosis. tRNA-Q modification plays an unexplored role in the pathogenesis of mitochondrial function in the intestine. Our upcoming research will employ N-acetyl-l-cysteine, a mitochondrial ROS inhibitor, and a Caspase 3 specific inhibitor to ascertain the role of tRNA modification in mitochondrial function in the intestinal inflammation. Insights into tRNA-Q modification will pave the road for new therapeutic strategies to restore mitochondrial function in IBD.

P149 Bacteroides uniformis ameliorates pro-inflammatory diet-exacerbated colitis by targeting endoplasmic reticulum stress-mediated ferroptosis

Abstract Background Pro-inflammatory diet is positively associated with the risk and progression of inflammatory bowel diseases. Recently, ferroptosis was observed in patients with dietary pattern-associated colitis. However, the mechanisms underlying the effects of a pro-inflammatory diet and whether it mediates ferroptosis are unknown. This study aimed to clarify the mechanisms of pro-inflammatory diet in colitis. Methods Mice were fed a dietary inflammatory index-based pro-inflammatory diet for 12 weeks. Subsequently, colitis was chemically induced using 2.5% dextran sulfate sodium with or without a ferroptosis inhibitor (ferrostatin-1). Body weight, histological scores, immune response, and mucosal barrier function were evaluated to assess intestinal inflammation.Colon tissue transcriptomics, fecal microbiome, and serum metabolomics were applied to identify diet-microbe-host interactions. Dietary inflammatory index of 36 patients with Crohn’s disease were evaluated. Their intestinal specimens were also collected. The biological functions of Bacteroides uniformis were observed in vitro and in vivo. Results Pro-inflammatory diet induced low-grade intestinal inflammation and exacerbated colitis by activating glutathione peroxidase 4-associated ferroptosis in the endoplasmic reticulum stress-mediated pathway; ferrostatin-1 treatment reversed this pro-inflammatory potential. Additionally, the pro-inflammatory diet triggered colitis by modulating the gut microbiota and metabolites. Notably, supplementation with B. uniformis improved the pro-inflammatory diet-aggravated colitis by inhibiting endoplasmic reticulum stress-mediated ferroptosis. Co-culturing B. uniformis with intestinal epithelial cells revealed it is non-enterotoxigenic and non-enteroinvasive. Conclusion Pro-inflammatory diet drives colitis by targeting endoplasmic reticulum stress-mediated ferroptosis, possibly in a gut microbiota-dependent manner. Pro-inflammatory diet restriction and microbial-based therapies may be effective strategies for preventing and treating inflammatory bowel disease.