Rheumatoid arthritis-celiac disease relationship: joints get that gut feeling

Therapeutic potential of probiotics in gut microbial homeostasis and Rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by inflammation and joint damage. Existing treatment options primarily focus on managing symptoms and slowing disease progression, often with side effects and limitations. The gut microbiome, a vast community of microorganisms present in the gastrointestinal tract, plays a crucial role in health and disease. Recent research suggests a bidirectional relationship between the gut microbiome and RA, highlighting its potential as a therapeutic option. This review focuses on the interaction between the gut microbiome and RA development, by discussing how dysbiosis, an imbalance in gut bacteria, can contribute to RA through multiple mechanisms such as molecular mimicry, leaky gut, and metabolic dysregulation. Probiotics, live microorganisms with health benefits, are emerging as promising tools for managing RA. They can prevent the negative effects of dysbiosis by displacing harmful bacteria, producing anti-inflammatory metabolites like short-chain fatty acids (SCFA), Directly influencing immune cells, and modifying host metabolism. animal and clinical studies demonstrate the potential of probiotics in improving RA symptoms and disease outcomes. However, further research is needed to optimize probiotic strains, dosages, and treatment protocols for personalized and effective management of RA. This review summarizes the current understanding of the gut microbiome and its role in RA and discusses future research directions. In addition to the established role of gut dysbiosis in RA, emerging strategies like fecal microbiota transplantation, prebiotics, and postbiotics offer exciting possibilities. However, individual variations in gut composition necessitate personalized treatment plans. Long-term effects and clear regulations need to be established. Future research focusing on metagenomic analysis, combination therapies, and mechanistic understanding will unlock the full potential of gut microbiome modulation for effective RA management.

Emerging role of gut microbiota in autoimmune diseases

Accumulating studies have indicated that the gut microbiota plays a pivotal role in the onset of autoimmune diseases by engaging in complex interactions with the host. This review aims to provide a comprehensive overview of the existing literatures concerning the relationship between the gut microbiota and autoimmune diseases, shedding light on the complex interplay between the gut microbiota, the host and the immune system. Furthermore, we aim to summarize the impacts and potential mechanisms that underlie the interactions between the gut microbiota and the host in autoimmune diseases, primarily focusing on systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, type 1 diabetes mellitus, ulcerative colitis and psoriasis. The present review will emphasize the clinical significance and potential applications of interventions based on the gut microbiota as innovative adjunctive therapies for autoimmune diseases.

Microbial Imbalance and Intestinal Permeability in the Pathogenesis of Rheumatoid Arthritis: A Mechanism Review with a Focus on Bacterial Translocation, Citrullination, and Probiotic Intervention

This review aims to investigate the role of intestinal permeability (IP) in rheumatoid arthritis (RA), following the hypotheses that leakage of intestinal microbes can influence increased citrullination of peptides leading to anti-citrullinated protein antibody (ACPA) production and inflammation in RA; and that leaked microbes can migrate to the peripheral joints, leading to immune responses and synovitis in peripheral joints. This review explored the evidence for the link between microbial dysbiosis and increased IP in the inflammatory state in RA, as well as the role of increased citrullination and bacterial translocation in the link between microbiota and immune responses in RA. Furthermore, this research aims to evaluate the potential effect of probiotics on RA symptoms and pathogenesis via proposed mechanisms, including the support of microbial balance and suppression of inflammatory factors in RA. A systematic literature search was conducted in three tranches (review, mechanism, intervention). 71 peer-reviewed papers met the inclusions criteria and are summarized in a narrative analysis. Primary studies were critically appraised, synthesized and their relevance to clinical practice evaluated. Evidence found in this mechanism review consistently supported intestinal dysbiosis and increased IP in arthritis. An altered intestinal microbiome was demonstrated in RA with specific microbes such as Collinsella and Eggerthella correlating with increased IP, mucosal inflammation, and immune responses. Hypercitrullination and ACPA production correlated with arthritic symptoms and intestinal microbes were shown to influence hypercitrullination. Some in vitro and animal studies demonstrated a link between leakage of microbes and bacterial translocation, but further research is needed to elucidate the link between IP and citrullination. Probiotic intervention studies evidenced reductions in inflammatory markers IL-6 and TNFα, associated with proliferation of synovial tissue and pain perception in RA joint inflammation. Despite some conflict in the literature, probiotics may present a promising nutritional intervention in the suppression of both, disease activity and inflammatory markers.Key teaching pointsThere is evidence for a dysbiotic profile of the RA gut with specific RA-associated microbes.Increased intestinal permeability and leakage of PAD enzyme facilitates citrullination of peptides.Hypercitrullination and ACPA production correlate to arthritic signs.Microbial leakage and translocation plays a role in the pathogenesis of RA.Probiotics (e.g. L. Casei 01) may reduce inflammation and ameliorate RA symptoms.

Cross-reactivity and sequence similarity between microbial transglutaminase and human tissue antigens

Microbial transglutaminase (mTG) is a bacterial survival factor, frequently used as a food additive to glue processed nutrients. As a result, new immunogenic epitopes are generated that might drive autoimmunity. Presently, its contribution to autoimmunity through epitope similarity and cross-reactivity was investigated. Emboss Matcher was used to perform sequence alignment between mTG and various antigens implicated in many autoimmune diseases. Monoclonal and polyclonal antibodies made specifically against mTG were applied to 77 different human tissue antigens using ELISA. Six antigens were detected to share significant homology with mTG immunogenic sequences, representing major targets of common autoimmune conditions. Polyclonal antibody to mTG reacted significantly with 17 out of 77 tissue antigens. This reaction was most pronounced with mitochondrial M2, ANA, and extractable nuclear antigens. The results indicate that sequence similarity and cross-reactivity between mTG and various tissue antigens are possible, supporting the relationship between mTG and the development of autoimmune disorders 150W.

The intestinal mucosal barrier - A key player in rheumatoid arthritis?

Rheumatoid arthritis (RA) is a recurrent chronic autoimmune disease, which is not only difficult to treat, but also has a great adverse impact on the physical and mental health of patients. The intestinal mucosa barrier has some relationship with RA and it consists of mechanical barrier, chemical barrier, immune barrier, and microflora barrier. It is a dynamic system that contributes to the stability of the intestinal environment by regulating the absorption of relevant substances from the lumen into the circulation, while limiting the passage of harmful substances. This article summarizes the connection between the intestinal mucosa barrier and RA, and proposes the role of relevant Chinese medicines on RA from the point of improving barriers, to provide new perspectives on the pathogenesis and therapeutic strategies of RA.

Epidemiological, Endoscopic, Clinical, and Pathological Features of Patients with Celiac Diseases in Southern Littoral of Caspian Sea

Background: Celiac disease is an autoimmune disorder resulting from gluten consumption in genetically predisposed individuals. The present study investigated the epidemiological, endoscopic, and clinicopathological features of patients with celiac disease in the southern littoral of the Caspian Sea. Methods: 140 patients with celiac disease were interviewed and examined regarding demographic characteristics, clinical symptoms, and serologic, endoscopic, and pathological findings. Results: 44 (31.4%) of the patients were male and 68.6% were female. The mean age of the patients at diagnosis was 27.13±13.4 years (ranging from 2 to 60 years). The most common gastrointestinal (GI) symptoms were bloating (47.8%), abdominal pain (47.1%) and diarrhea (30.7%), respectively. Also, 17 (12.1%) patients did not complain of any GI symptoms.18 (12.8%) patients had aphthous stomatitis, 10.7% had dermatitis herpetiformis, 3.6% suffered from itching without a rash, two (1.4%) mentioned psoriasis and one (0.7%) had lichen planus. 19 (19.7%) of the female patients complained of menstrual bleeding disorders, 4% mentioned infertility, and 2% experienced primary amenorrhea. The most common comorbid condition was hypothyroidism in 16 (11.4%) patients. The most common endoscopic finding was duodenal scalloping (37.25%). In addition, 7.8% of the patients had a normal endoscopic appearance. 43 (30.7%) patients were classified as Marsh IIIC, 25.7% Marsh IIIB, 17.8% Marsh IIIA, 12.8% Marsh II and 12.8% were classified as Marsh I. Conclusion: Since celiac disease can present with non-GI manifestations and the majority of our patients had Marsh III classification, it seems that celiac disease must be considered as a routine screening test in GI clinics, and also, it should be kept in mind as a differential diagnosis in other specialty fields.

Autoimmune polyendocrine syndromes associated with autoimmune rheumatic diseases

Autoimmune polyendocrine syndromes (APSs), also called autoimmune polyglandular syndromes, are a group of autoimmune diseases characterized by the co-occurrence of dysfunctions of several (at least two) endocrine glands. They develop under the influence of environmental factors in genetically predisposed people. Autoimmune polyendocrine syndromes may accompany autoimmune rheumatic diseases and worsen their course - APS-2 and APS-3 are the most common. The APS-2 includes the coexistence of, e.g. Hashimoto's disease, celiac disease and rheumatoid arthritis (RA). In APS-3, rheumatic diseases such as RA, systemic lupus erythematosus, and Sjögren's syndrome may coexist with Hashimoto's disease, type 1 diabetes and hypogonadism or other endocrinopathies. Undiagnosed endocrine diseases may be the reason for the intensification of metabolic disorders observed in the course of rheumatic diseases, cause the ineffectiveness of rheumatological treatment and also increase the frequency of bone fractures due to osteoporosis, cardiovascular complications and even miscarriages when coexistent, e.g. Hashimoto's disease with hypothyroiditis, which increases the risk of pregnancy loss. It is important to be able to conduct an extensive interview, paying attention to the symptoms of possible endocrinopathy as well as the features of other autoimmune disorders in the physical examination (e.g. vitiligo or darkening of the skin in Addison's disease). Depending on the history and physical examination, screening for various APSs is advised.

Isolated polyarthritis revealing celiac disease: A case report

Nonclassical celiac disease is a diagnostic challenge for the practitioner. We report a case of a 28-year-old Moroccan woman who had been experiencing polyarthralgia and joint swelling for 8 weeks, despite treatment with nonsteroidal anti-inflammatory drugs and corticosteroids. On physical examination, there was effusion in the proximal interphalangeal joints, metacarpophalangeal joints, wrists, knees, and ankles. Laboratory tests revealed microcytic anemia, elevated levels of inflammation markers, low ferritin, and a low vitamin D level. An upper gastrointestinal endoscopy was performed to investigate the cause of anemia, revealing the loss of duodenal folds. Subsequently, a duodenal biopsy was performed, and serological testing for celiac disease was requested. Anti-transglutaminase-2 antibodies were elevated at 200 U/ml (normal < 15U/ml). The duodenal biopsy showed flattened duodenal mucosal epithelium. The patient was diagnosed with celiac disease. A gluten-free diet was started. Her joint symptoms resolved in 3 weeks. All blood tests returned to normal levels after 48 weeks. This case illustrates that celiac disease should be considered in cases of arthritis with an initial negative etiological workup.

Mechanistic Insights into Immune-Microbiota Interactions and Preventive Role of Probiotics Against Autoimmune Diabetes Mellitus

Recent studies on genetically susceptible individuals and animal models revealed the potential role of the intestinal microbiota in the pathogenesis of type 1 diabetes (T1D) through complex interactions with the immune system. T1D incidence has been increasing exponentially with modern lifestyle altering normal microbiota composition, causing dysbiosis characterized by an imbalance in the gut microbial community. Dysbiosis has been suggested to be a potential contributing factor in T1D. Moreover, several studies have shown the potential role of probiotics in regulating T1D through various mechanisms. Current T1D therapies target curative measures; however, preventive therapeutics are yet to be proven. This review highlights immune microbiota interaction and the immense role of probiotics and postbiotics as important immunological interventions for reducing the risk of T1D.

Combined treatment with glucosamine and chondroitin sulfate improves rheumatoid arthritis in rats by regulating the gut microbiota

BACKGROUND

To investigate the ameliorative effects of glucosamine (GS), chondroitin sulphate (CS) and glucosamine plus chondroitin sulphate (GC) on rheumatoid arthritis (RA) in rats, and to explore the mechanism of GS, CS and GC in improving RA based on the gut microbiota.

METHODS

RA rat models were effectively developed 14 days after CFA injection, and then garaged with GS, CS and GC. Body weight and paw volume of rats were monitored at multiple time points at the beginning of CFA injection. Until D₃₆, serum and ankle tissue specimens were used to measure levels of circulating inflammatory factors (TNF-α, IL-1β, MMP-3, NO and PGE₂) and local inflammatory indicators (TLR-4 and NF-κB). On D₁₈, D₂₅, and D₃₆, intergroup gut microbiota was compared using 16S rRNA gene sequencing and bioinformatics analysis. We also performed the correlation analysis of gut bacteria, joint swelling and inflammatory indicators.

RESULTS

GC, rather than GS and CS, could reduce right paw volumes, levels of TLR-4 and NF-κB in synovial tissues. In addition, enriched genera in RA model rats screened out by LEfSe analysis could be inhibited by GC intervention, including potential LPS-producing bacteria (Enterobacter, Bacteroides, Erysipelotrichaceae_unclassified and Erysipelotrichaceae_uncultured) and some other opportunistic pathogens (Esherichia_Shigella, Nosocomiicoccus, NK4A214_group, Odoribacter, Corynebacterium and Candidatus_Saccharimonas.etc.) that positively correlated with pro-inflammatory cytokines, right paw volume, and pathology scores. Furthermore, the gut microbiota dysbiosis was observed to recover before alleviating joint swelling after interventions.

CONCLUSIONS

GC could inhibit potential LPS-producing bacteria and the activation of TLR-4/NF-κB pathway in RA rats, thus alleviating RA-induced joint injury.

Malignancies in Patients with Celiac Disease: Diagnostic Challenges and Molecular Advances

Celiac disease (CD) is a multiorgan autoimmune disorder of the chronic intestinal disease group characterized by duodenal inflammation in genetically predisposed individuals, precipitated by gluten ingestion. The pathogenesis of celiac disease is now widely studied, overcoming the limits of the purely autoimmune concept and explaining its hereditability. The genomic profiling of this condition has led to the discovery of numerous genes involved in interleukin signaling and immune-related pathways. The spectrum of disease manifestations is not limited to the gastrointestinal tract, and a significant number of studies have considered the possible association between CD and neoplasms. Patients with CD are found to be at increased risk of developing malignancies, with a particular predisposition of certain types of intestinal cancer, lymphomas, and oropharyngeal cancers. This can be partially explained by common cancer hallmarks present in these patients. The study of gut microbiota, microRNAs, and DNA methylation is evolving to find the any possible missing links between CD and cancer incidence in these patients. However, the literature is extremely mixed and, therefore, our understanding of the biological interplay between CD and cancer remains limited, with significant implications in terms of clinical management and screening protocols. In this review article, we seek to provide a comprehensive overview of the genomics, epigenomics, and transcriptomics data on CD and its relation to the most frequent types of neoplasms that may occur in these patients.

Gluten Degradation by the Gut Microbiota of Ulcerative Colitis Patients

Several studies have reported improved disease symptomatology in ulcerative colitis (UC) patients consuming a gluten free diet. This observation coupled with diversity depletion in the gut microbiota of UC patients led us to hypothesize that UC-associated enteric microbes differentially metabolize dietary gluten to produce immunogenic products that promote inflammation. Gluten concentration in stool was determined using gluten-specific ELISA, and gluten intake was assessed by food frequency questionnaire (FFQ) in UC (n = 12) and healthy controls (HC; n = 13). Gluten-metabolizing bacteria were isolated on minimal media supplemented with 1% gluten from UC and HC and identified by 16S rRNA profiling. Cell-free culture media from gluten metabolizing gut bacterial isolates was assessed for immunogenicity in vitro using HT29 colonocytes. Compared to HC, UC patients did not consume gluten differently (Mann−Whitney; p > 0.10) and exhibited equivalent levels of gluten in their feces (Mann−Whitney; p = 0.163). The profile of gluten-degrading bacteria isolated from UC stool was distinct (Chi-square; p ≤ 0.0001). Compared with Enterococcus isolates, products of gluten degradation by Bacillus strains induced higher IL8 and lower occludin (Mann−Whitney; p = 0.002 and p = 0.059, respectively) gene expression in colonocytes irrespective of whether they originated from UC or healthy gut. Members of HC and UC microbiota exhibit gluten-degrading ability, metabolites of which influence genes involved in inflammation and barrier function in enteric colonocyte cultures. Preliminary findings of this study warrant further investigations into the mechanisms by which gut microbiota contribute to UC pathogenesis through gluten degradation.

Evaluation of Gluten Exclusion for the Improvement of Rheumatoid Arthritis in Adults

There is currently a growing anti-gluten trend which, except for individuals with coeliac disease and non-coeliac gluten sensitivity (NCGS) for whom its intake is contraindicated, results in gluten (the main protein in wheat and other cereals) being considered harmful to health and excluded from diets, largely due to information distributed through social networks. However, in many cases the recommendation to exclude gluten from the diet goes beyond personal choice and is promoted by health professionals. This choice and/or recommendation is especially important to individuals with chronic inflammatory diseases such as rheumatoid arthritis (RA), for which this exclusion is justified to reduce the symptoms of the disease. The aim of this literature review is to assess whether there is scientific evidence to justify the elimination of gluten in patients with RA, neither coeliac nor with NCGS, to improve their symptoms and quality of life. The results of the search on gluten and RA carried out in the Embase database and the extraction of data from 16 articles included in the review are presented. No scientific evidence was found to recommend the exclusion of gluten in patients with RA.

Risk of Juvenile Idiopathic Arthritis and Rheumatoid Arthritis in Patients With Celiac Disease: A Population-Based Cohort Study

INTRODUCTION

Celiac disease (CD) is associated with many immune-mediated conditions, but a definitive epidemiological association between CD and juvenile idiopathic arthritis (JIA) or rheumatoid arthritis (RA) has not been established. We quantified the risk of JIA and RA among patients with CD using a population-based cohort.

METHODS

We identified patients diagnosed with biopsy-proven CD between 2004 and 2017 using data from a national histopathology cohort in Sweden. Each patient was matched by age, sex, calendar year, and geographic region to reference individuals in the general population. We calculated the incidence and estimated the relative risk, through Cox proportional hazards models, of JIA in individuals with CD aged <18 and of RA in individuals with CD aged ≥18.

RESULTS

We identified 24,014 individuals with CD who were matched to 117,397 reference individuals from the general population. Among individuals aged <18, the incidence rate of JIA was 5.9 per 10,000 person-years in patients with CD and 2.2 per 10,000 person-years in the general population (n events = 40 and 73, respectively; hazard ratio [HR] 2.68, 95% confidence interval 1.82-3.95) over a follow-up of 7.0 years. Among individuals aged ≥ 18, the incidence of RA was 8.4 per 10,000 person-years in CD and 5.1 per 10,000 person-years in matched comparators (n events = 110 and 322, respectively; HR 1.70, 95% confidence interval 1.36-2.12) over a follow-up of 8.8 years.

DISCUSSION

Among children with CD, JIA develops nearly 3 times as often as it does in the general population, and among adults with CD, RA occurs nearly 2 times as often. Clinicians caring for patients with CD with joint symptoms should have a low threshold to evaluate for JIA or RA.

Causal association between rheumatoid arthritis and celiac disease: A bidirectional two-sample mendelian randomization study

Objectives: Rheumatoid Arthritis (RA) has been associated with Celiac Disease (CD) in previous observational epidemiological studies. However, evidence for this association is limited and inconsistent, and it remains uncertain whether the association is causal or due to confounding or reverse causality. This study aimed to assess the bidirectional causal relationship between RA and CD. Methods: In this two-sample Mendelian randomization (MR) study, instrumental variables (IVs) for RA were derived from a genome-wide association studies (GWAS) meta-analysis including 58,284 subjects. Summary statistics for CD originated from a GWAS meta-analysis with 15,283 subjects. The inverse-variance weighted (IVW) method was used as the primary analysis. Four complementary methods were applied, including the weighted-median, weighted mode, MR pleiotropy residual sum and outlier (MR-PRESSO) test and MR-Egger regression, to strengthen the effect estimates. Results: Positive causal effects of genetically increased RA risk on CD were derived [IVW odds ratio (OR): 1.46, 95% confidence interval (CI): 1.19-1.79, p = 3.21E-04]. The results of reverse MR analysis demonstrated no significant causal effect of CD on RA (IVW OR: 1.05, 95% CI: 0.91-1.21, p = 0.499). According to the sensitivity analysis, horizontal pleiotropy was unlikely to distort the causal estimates. Conclusion: This study reveals a causality of RA on CD but not CD on RA among patients of European descent. This outcome suggests that the features and indicators of CD should regularly be assessed for RA patients.

Phenome of coeliac disease vs. inflammatory bowel disease

Coeliac disease (CeD) is characterized by gliadin-induced intestinal inflammation appearing in genetically susceptible individuals, such as HLA-DQ2.5 carriers. CeD, as well as other chronic intestinal disorders, such as Crohn's disease (CD) and ulcerative colitis, has been associated with increased morbidity and mortality, but the causes are unknown. We systematically analysed CeD-associated diagnoses and compared them to conditions enriched in subjects with CD/UC as well as in HLA-DQ2.5 carriers without CeD. We compared the overall and cause-specific mortality and morbidity of 3,001 patients with CeD, 2,020 with CD, 4,399 with UC and 492,200 controls in the community-based UK Biobank. Disease-specific phenotypes were assessed with the multivariable Phenome Wide Association Study (PheWAS) method. Associations were adjusted for age, sex and body mass index. All disease groups displayed higher overall mortality than controls (CD: aHR = 1.91[1.70-2.17]; UC: aHR = 1.32 [1.20-1.46]; CeD: aHR = 1.38 [1.22-1.55]). Cardiovascular and cancer-related deaths were responsible for the majority of fatalities. PheWAS analysis revealed 166 Phecodes overrepresented in all three disorders, whereas only ~ 20% of enriched Phecodes were disease specific. Seven of the 58 identified CeD-specific Phecodes were enriched in individuals homozygous for HLA-DQ2.5 without diagnosed CeD. Four out of these seven Phecodes and eight out of 19 HLA-DQ2.5 specific Phecodes were more common in homozygous HLA-DQ2.5 subjects with vs. without CeD, highlighting the interplay between genetics and diagnosis-related factors. Our study illustrates that the morbidity and mortality in CeD share similarities with CD/UC, while the CeD-restricted conditions might be driven by both inherited and acquired factors.

Celiac Disease Masquerading as Arthralgia

Celiac disease is an immune-mediated disorder triggered by dietary gluten. It classically presents with gastrointestinal symptoms. It may also present with atypical manifestations like anemia, arthritis, infertility, or other neurological symptoms. However, arthralgia as a sole manifestation of celiac disease is a rare clinical scenario. Even though the clinical spectrum of celiac disease is broad, prompt diagnosis and management exert a protective effect against complications of celiac disease. We want to highlight and expand on the existing knowledge on atypical presentations about celiac disease.

Role of Gut Microbiota in Pulmonary Arterial Hypertension

Gut microbiota and its metabolites play an important role in maintaining host homeostasis. Pulmonary arterial hypertension (PAH) is a malignant clinical syndrome with a frightening mortality. Pulmonary vascular remodeling is an important feature of PAH, and its pathogenesis is not well established. With the progress of studies on intestinal microbes in different disease, cumulative evidence indicates that gut microbiota plays a major role in PAH pathophysiology. In this review, we will systematically summarize translational and preclinical data on the correlation between gut dysbiosis and PAH and investigate the role of gut dysbiosis in the causation of PAH. Then, we point out the potential significance of gut dysbiosis in the diagnosis and treatment of PAH as well as several problems that remain to be resolved in the field of gut dysbiosis and PAH. All of this knowledge of gut microbiome might pave the way for the extension of novel pathophysiological mechanisms, diagnosis, and targeted therapies for PAH.

In a large Juvenile Idiopathic Arthritis (JIA) cohort, concomitant celiac disease is associated with family history of autoimmunity and a more severe JIA course: a retrospective study

BACKGROUND

A higher prevalence of celiac disease (CD) has been reported in patients with juvenile idiopathic arthritis (JIA) compared to the general population. Factors related to the increased risk of co-occurrence and associated disease course have not been fully elucidated. Aims of this study were to determine the prevalence of CD in a large Southern Italian cohort of children with JIA, describe their clinical features and disease course and investigate risk factors associated with their co-occurrence.

FINDINGS

Demographic, clinical and laboratory data of all patients with JIA admitted to our Pediatric Rheumatology Unit from January 2001 to June 2019, who underwent CD screening, were retrospectively extracted from clinical charts and analyzed. Eight of 329 JIA patients were diagnosed with CD, resulting in a prevalence higher than the general Italian population (2.4% vs 0.93%, p < 0.05). Familiarity for autoimmunity was reported by 87.5% patients with JIA and CD compared to 45.8% of those without CD (p < 0.05). 87.5% patients with JIA and CD required both a conventional Disease Modifying Anti-Rheumatic Drug (DMARD) and a biological DMARD over time compared to 36.4% of those without CD (p < 0.05).

CONCLUSION

A higher CD prevalence was found in a large JIA cohort, supporting the need for CD screening in all JIA children, especially those with a family history of autoimmunity, found to be associated with the co-occurrence of the two diseases. This is clinically relevant since patients with CD and JIA more often required a step-up therapy, suggesting a more severe JIA clinical course.

Anti-proliferation and anti-inflammation effects of corilagin in rheumatoid arthritis by downregulating NF-κB and MAPK signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

The dried aboveground part of Geranium Wilfordii Maxim. (G. Wilfordii) is a traditional Chinese herbal medicine named lao-guan-cao. It has long been used for dispelling wind-dampness, unblocking meridians, and stopping diarrhea and dysentery. Previous investigations have revealed that 50% ethanolic extract of G. Wilfordii has anti-inflammatory and anti-proliferation activities on TNF-α induced murine fibrosarcoma L929 cells. Corilagin (COR) is a main compound in G. Wilfordii with the content up to 1.69 mg/g. Pharmacology study showed that COR has anti-inflammatory, anti-tumor, anti-microorganism, anti-oxidant, and hepatoprotective effects. However, there is no any investigation on its anti-proliferation and anti-inflammation effects in rheumatoid arthritis (RA).

AIM OF THE STUDY

The present study aimed to evaluate the potential pharmacological mechanisms of anti-proliferation and anti-inflammation effects of COR in RA.

MATERIALS AND METHODS

In vitro, MH7A cells model induced by IL-1β was used. The anti-proliferation activity of COR was assessed by Cell Counting Kit-8 (CCK-8) assay, and the anti-migration and anti-invasion activity of COR was determined by wound healing assay and transwell assay, respectively. Furthermore, apoptosis assay by flow cytometer was used to measure the pro-apoptotic effect of COR. The mRNA expressions of Bax, Bcl-2, IL-6, IL-8, MMP-1, MMP-2, MMP-3, MMP-9, COX-2, and iNOS were measured by qRT-PCR, and related protein were further verified by ELISA kits or Western blot. Moreover, protein levels associated with NF-κB and MAPK signaling pathways of p65, P-p65, IκBα, P-IκBα, ERK1/2, P-ERK1/2, JNK, P-JNK1/2/3, p38, and P-p38 were determined by Western blot. The nuclear translocation of NF-κB-p65 was detected by immunofluorescent staining. In vivo, adjuvant-induced arthritis (AIA) rat model was used, and the body weight, paw swelling, and arthritis score during the entire period were measured. Histopathological analysis of joints of synovial tissues was also determined. The expression of pro-inflammatory cytokines in serum including IL-6, TNF-α, IL-1β, and IL-17 were measured.

RESULTS

The in vitro results showed that COR could dose-dependently inhibit the proliferation, migration, and invasion of IL-1β-induced MH7A cells, as well as promote its apoptosis. Moreover, it also suppressed the over-expression of Bcl-2, IL-6, IL-8, MMP-1, MMP-2, MMP-3, MMP-9, COX-2, and iNOS while up-regulated the level of Bax. Besides, the ratios of P-p65/p65, P-IκBα/IκBα, P-ERK/ERK, P-JNK/JNK, and P-p38/p38 were decreased, and the nuclear translocation of p65 induced by IL-1β was blocked by COR. In vivo results indicated that COR significantly reduced the paw swelling and arthritis score in AIA rats, and inhibited synovial tissue hyperplasia and erosion, as well as inflammatory cells infiltration. It also decreased the serum pro-inflammatory cytokines (IL-6, TNF-α, IL-1β, and IL-17) production.

CONCLUSION

These results revealed that COR exerted anti-rheumatoid arthritis effect, and its underlying mechanisms may be related to inhibiting the proliferation, migration, and invasion of synovial fibroblasts, enhancing cell apoptosis, and suppressing inflammatory responses via downregulating NF-κB and MAPK signaling pathways.

Frequency of serological markers of rheumatoid arthritis in adult patients with active celiac disease

BACKGROUND

Celiac disease (CD) and rheumatoid arthritis (RA) are multisystem autoimmune diseases affecting 1% of general populationa. Both diseases share genetic and immunological features.

AIM

In this retrospective study, we aim to determine the frequency of auto-antibodies of RA in adult patients with CD.

MATERIALS AND METHODS

Seventy seven adult patients with active CD were included in the present study. Ninety healthy blood donors (HBD) served as control group. Anti-cyclic citrullinated peptides antibodies (CCP-Ab) and rheumatoid factors (RF; IgA, IgG and IgM) were determined by enzyme linked immunosorbent assay (ELISA) for patients and control group. For statistical analysis, we used Chi-square or Fisher's exact test.

RESULTS

Our study included 77 adult patients with active celiac disease (57 female, 20 male). Twenty-four (31.2%) active celiac patients and 7 (7.8%) blood donors had CCP-Ab or RF (31.2% vs 7.8%, p < 10-4). Only two patients (2.6%) had both CCP-Ab and RF. IgA was the predominant isotype of RF in celiac patients (n = 18; 23.4%) while none of healthy blood donors had RF-IgA (23.4% vs 0.0%, p < 10-4).

CONCLUSION

The current study has shown that CD is associated with a high frequency of RF-IgA suggesting that celiac patients could be at a higher risk of developing RA.

Rheumatologische Erkrankungen und der Gastrointestinaltrakt

Die meisten rheumatologischen Krankheitsbilder können Einfluss auf den Gastrointestinaltrakt haben. Dabei können intestinale Manifestationen (z. B. rheumatoide Vaskulitis, IgG4-assoziierte Pankreatitis, IgG4-assoziierte Cholangitis, Lupus-Enteritis, Polyarteriitis nodosa, Purpura Schoenlein-Henoch, nekrotisierende Vaskulitis), assoziierte intestinale Erkrankungen (chronisch-entzündliche Darmerkrankungen (CED), Zöliakie) und intestinale Komplikationen der rheumatologischen Erkrankung (z. B. Amyloidose, erosive Refluxerkrankung bei Sklerodermie) bzw. ihrer Behandlung (z. B. NSAR-Magenulcus, MTX-Mukositis, Soor-Ösophagitis, intestinale Tuberkulose, ulzerierende HSV-Ösophagitis, CMV-Kolitis) voneinander abgegrenzt werden. Dadurch kommen gastrointestinale Symptome bei Patienten mit rheumatologischen Erkrankungen sehr häufig vor. Die Diagnosestellung (er)fordert Gastroenterologen im interdisziplinären Behandlungsnetzwerk mit Rheumatologen. Insbesondere bei Behandlung von CED ergeben sich für die überschneidenden Zulassungsindikationen der zur Verfügung stehenden Medikamente in der interdisziplinären Absprache zwischen Rheumatologen und Gastroenterologen synergistische Behandlungsoptionen.

Lactobacillus rhamnosus Affects Rat Peritoneal Cavity Cell Response to Stimulation with Gut Microbiota: Focus on the Host Innate Immunity

Gut microbiota contribute to shaping the immune repertoire of the host, whereas probiotics may exert beneficial effects by modulating immune responses. Having in mind the differences in both the composition of gut microbiota and the immune response between rats of Albino Oxford (AO) and Dark Agouti (DA) rat strains, we investigated if intraperitoneal (i.p.) injection of live Lactobacillus rhamnosus (LB) may influence peritoneal cavity cell response to in vitro treatments with selected microbiota in the rat strain-dependent manner. Peritoneal cavity cells from AO and DA rats were lavaged two (d2) and seven days (d7) following i.p. injection with LB and tested for NO, urea, and H₂O₂ release basally, or upon in vitro stimulation with autologous E.coli and Enterococcus spp. Whereas the single i.p. injection of LB nearly depleted resident macrophages and increased the proportion of small inflammatory macrophages and monocytes on d2 in both rat strains, greater proportion of MHCII^hiCD163^- and CCR7⁺ cells and increased NO/diminished H₂O₂ release in DA compared with AO rats suggest a more intense inflammatory priming by LB in this rat strain. Even though E.coli- and/or Enterococcus spp.-induced rise in H₂O₂ release in vitro was abrogated by LB in cells from both rat strains, LB prevented microbiota-induced increase in NO/urea ratio only in cells from AO and augmented it in cells from DA rats. Thus, the immunomodulatory properties may not be constant for particular probiotic bacteria, but shaped by innate immunity of the host.

Microbiome in Rheumatoid Arthritis and Celiac Disease: A Friend or Foe

Rheumatoid arthritis (RA) and celiac disease (CD) are both autoimmune diseases with increasing global prevalence. These two diseases have been connected based on similar HLA mutations, serological markers, rheumatological, and gastrointestinal manifestations. In this review, we discuss the role of the oral and gut microbiome in the development and progression of RA and CD. Here, we highlight similar microbial dysbiosis and how these alterations in composition can lead to worsening disease severity in both CD and RA. Additionally, we analyze the role of probiotics in regulating the microbiome and improving symptoms associated with RA and CD.

Alpha-enolase involvement in intestinal and extraintestinal manifestations of celiac disease

Celiac disease is a life-long intestinal autoimmune disease, characterized by the gluten intolerance and chronic enteric inflammation. Traditionally presented by intestinal manifestations, however, a shift toward extra intestinal presentation is taking place. One of the affected organs is the nervous systems presented by neuropsychiatric manifestations, hence the mechanism and pathways are not clear. The presence of neuronal and alpha-enolases and their corresponding antibodies were noticed in the mucosa and serum of celiac disease patients, as well as in other various autoimmune diseases with psycho-neurological manifestations. The aims of the present review are to screen the literature on different isoforms of enolase, mainly alpha enolase, and their specific antibodies and to suggest their potential pathophysiological mechanisms relaying the enolases to intestinal or extraintestinal celiac disease manifestations. The shared aspects between the enolases and celiac disease and the cross-talks between alpha-enolase and tissue transglutaminase suggest new potential pathophysiological mechanisms that might drive celiac disease evolvement.

Intestinal changes associated with fluoride exposure in rats: Integrative morphological, proteomic and microbiome analyses

Gastrointestinal signs and symptoms are the first signs of toxicity due to exposure to fluoride (F). This suggests the possibility that lower levels of subchronic F exposure may affect the gut. The aim of this study was to evaluate changes in the morphology, proteome and microbiome of the ileum of rats, after subchronic exposure to F. Male rats ingested water with 0, 10, or 50 mgF/L for thirty days. Treatment with F, regardless of the dose, significantly decreased the density of HuC/D-IR neurons, whereas CGRP-IR and SP-IR varicosities were significantly increased compared to the control group. Increased VIP-IR varicosities were significantly increased only in the group treated with 50 mgF/L. A significant increase in thickness of the tunica muscularis, as well as in the total thickness of the ileum wall was observed at both F doses when compared to controls. In proteomics analysis, myosin isoforms were increased, and Gastrotopin was decreased in F-exposed mice. In the microbiome metagenomics analysis, Class Clostridia was significantly reduced upon exposure to 10 mgF/L. At the higher F dose of 50 mg/L, genus Ureaplasma was significantly reduced in comparison with controls. Morphological and proteomics alterations induced by F were marked by changes associated with inflammation, and alterations in the gut microbiome. Further studies are needed to determine whether F exposure increases inflammation with secondary effects of the gut microbiome, and/or whether primary effects of F on the gut microbiome enhance changes associated with inflammation.

Intragastric Administration of Casein Leads to Nigrostriatal Disease Progressed Accompanied with Persistent Nigrostriatal-Intestinal Inflammation Activited and Intestinal Microbiota-Metabolic Disorders Induced in MPTP Mouse Model of Parkinson's Disease

Gut microbial dysbiosis and alteration of gut microbiota composition in Parkinson's disease (PD) have been increasingly reported, no recognized therapies are available to halt or slow progression of PD and more evidence is still needed to illustrate its causative impact on gut microbiota and PD and mechanisms for targeted mitigation. Epidemiological evidence supported an association between milk intake and a higher incidence of Parkinson's disease (PD), questions have been raised about prospective associations between dietary factors and the incidence of PD. Here, we investigated the significance of casein in the development of PD. The mice were given casein (6.75 g/kg i.g.) for 21 days after MPTP (25 mg/kg i.p. × 5 days) treatment, the motor function, dopaminergic neurons, inflammation, gut microbiota and fecal metabolites were observed. The experimental results revealed that the mice with casein gavage after MPTP treatment showed a persisted dyskinesia, the content of dopamine in striatum and the expression of TH in midbrain and ileum were decreased, the expression of Iba-1, CD4, IL-22 in midbrain and ileum increased continuously with persisted intestinal histopathology and intestinal barrier injury. Decreased intestinal bile secretion in addition with abnormal digestion and metabolism of carbohydrate, lipids and proteins were found, whereas these pathological status for the MPTP mice without casein intake had recovered after 24 days, no significant differences were observed with regard to only treated with casein. Our study demonstrates that intestinal pathologic injury, intestinal dysbacteriosis and metabolism changes promoted by casein in MPTP mice ultimately exacerbated the lesions to dopaminergic neurons.

Interplay of Microbiota and Citrullination in the Immunopathogenesis of Rheumatoid Arthritis

Microbiota is a balanced ecosystem that has important functions to the host health including development, defense, digestion, and absorption of dietary fibers and minerals, vitamin synthesizes, protection, and training the host immune system. On the other hand, its dysbiosis is linked to many human diseases such as rheumatoid arthritis (RA). The RA is an inflammatory autoimmune disorder caused by genetic and environmental factors; microbiota may be considered as a risk environmental factor for it. Citrullination is a post-translation modification (PMT) that converts the amino acid arginine to amino acid citrulline in certain proteins. These citrullinated proteins are recognized as a foreign antigen by the immune system resulting in the upregulation of inflammatory action such as in RA. The current work highlights the effect of both gut and oral microbiota dysbiosis on the development of RA, as well as discusses how the alteration in microbiota composition leads to the overgrowth of some bacterial species that entangled in RA pathogenicity. The evidence suggested that some oral and gut microbial species such as Porphyromonas gingivalis and Prevotella copri, respectively, contribute to RA pathogenesis. During dysbiosis, these bacteria can mediate the citrullination of either human or bacteria proteins to trigger an immune response that leads to the generation of autoantibodies.

Cross-Reactivity and Sequence Homology Between Alpha-Synuclein and Food Products: A Step Further for Parkinson's Disease Synucleinopathy

INTRODUCTION

Parkinson's disease is characterized by non-motor/motor dysfunction midbrain neuronal death and α-synuclein deposits. The accepted hypothesis is that unknown environmental factors induce α-synuclein accumulation in the brain via the enteric nervous system.

MATERIAL AND METHODS

Monoclonal antibodies made against recombinant α-synuclein protein or α-synuclein epitope 118-123 were applied to the antigens of 180 frequently consumed food products. The specificity of those antibody-antigen reactions was confirmed by serial dilution and inhibition studies. The Basic Local Alignment Search Tool sequence matching program was used for sequence homologies.

RESULTS

While the antibody made against recombinant α-synuclein reacted significantly with 86/180 specific food antigens, the antibody made against α-synuclein epitope 118-123 reacted with only 32/180 tested food antigens. The food proteins with the greatest number of peptides that matched with α-synuclein were yeast, soybean, latex hevein, wheat germ agglutinin, potato, peanut, bean agglutinin, pea lectin, shrimp, bromelain, and lentil lectin. Conclusions: The cross-reactivity and sequence homology between α-synuclein and frequently consumed foods, reinforces the autoimmune aspect of Parkinson's disease. It is hypothesized that luminal food peptides that share cross-reactive epitopes with human α-synuclein and have molecular similarity with brain antigens are involved in the synucleinopathy. The findings deserve further confirmation by extensive research.

Nutri-epigenetics: the effect of maternal diet and early nutrition on the pathogenesis of autoimmune diseases

Autoimmune diseases comprise a wide group of diseases involving a self-response of the immune system against the host. The etiopathogenesis is very complex involving disease-specific factors but also environmental factors, among which the diet. Maternal diet during pregnancy as well as early nutrition recently attracted the interest of the scientists as contributing to the immune programming. In this paper, we reviewed the most recent literature on the effect of maternal diet and early nutrition in modulating the immune system in a selected subset of autoimmune diseases: type 1 diabetes, celiac disease, inflammatory bowel disease, juvenile idiopathic arthritis and rheumatoid arthritis. Particularly, we focused our narrative on the role of maternal and perinatal nutrition in the epigenetic mechanisms underlying the auto-immune response. Maternal diet during pregnancy as well as breastfeeding and early nutrition play a big role in many epigenetic mechanisms. Most of the nutrients consumed by the mother and the infant are known exerting epigenetic functions, such as folate, methionine, zinc, vitamins B12 and D, fibers, casein and gliadin, and they were linked to gene expression changes in the immune pathways. Despite the common role of maternal diet, breastfeeding and early nutrition in almost all the autoimmune diseases, each disease seems to have specific diet-driver epigenetic mechanisms that require further investigations. The research in this field is opening new routes to establishing a precision nutrition approach to the auto-immune diseases.

Contribution of Infectious Agents to the Development of Celiac Disease

The ingestion of wheat gliadin (alcohol-soluble proteins, an integral part of wheat gluten) and related proteins induce, in genetically predisposed individuals, celiac disease (CD), which is characterized by immune-mediated impairment of the small intestinal mucosa. The lifelong omission of gluten and related grain proteins, i.e., a gluten-free diet (GFD), is at present the only therapy for CD. Although a GFD usually reduces CD symptoms, it does not entirely restore the small intestinal mucosa to a fully healthy state. Recently, the participation of microbial components in pathogenetic mechanisms of celiac disease was suggested. The present review provides information on infectious diseases associated with CD and the putative role of infections in CD development. Moreover, the involvement of the microbiota as a factor contributing to pathological changes in the intestine is discussed. Attention is paid to the mechanisms by which microbes and their components affect mucosal immunity, including tolerance to food antigens. Modulation of microbiota composition and function and the potential beneficial effects of probiotics in celiac disease are discussed.

The Emerging World of Microbiome in Autoimmune Disorders: Opportunities and Challenges

Trillions of commensal bacteria colonizing humans (microbiome) have emerged as essential player(s) in human health. The alteration of the same has been linked with diseases including autoimmune disorders such as multiple sclerosis, rheumatoid arthritis, systemic lupus erythematosus, and ankylosing spondylitis. Gut bacteria are separated from the host through a physical barrier such as skin or gut epithelial lining. However, the perturbation in the healthy bacterial community (gut dysbiosis) can compromise gut barrier integrity, resulting in translocation of bacterial contents across the epithelial barrier (leaky gut). Bacterial contents such as lipopolysaccharide and bacterial antigens can induce a systemic inflammatory environment through activation and induction of immune cells. The biggest question in the field is whether inflammation causes gut dysbiosis or dysbiosis leads to disease induction or propagation, i.e., it is inside out or outside in or both. In this review, we first discuss the microbiome profiling studies in various autoimmune disorders, followed by a discussion of potential mechanisms through which microbiome is involved in the pathobiology of diseases. A better understanding of the role of the microbiome in health and disease will help us harness the power of commensal bacteria for the development of novel therapeutic agents to treat autoimmune disorders.

Cancer Related Anemia: An Integrated Multitarget Approach and Lifestyle Interventions

Cancer is often accompanied by worsening of the patient's iron profile, and the resulting anemia could be a factor that negatively impacts antineoplastic treatment efficacy and patient survival. The first line of therapy is usually based on oral or intravenous iron supplementation; however, many patients remain anemic and do not respond. The key might lie in the pathogenesis of the anemia itself. Cancer-related anemia (CRA) is characterized by a decreased circulating serum iron concentration and transferrin saturation despite ample iron stores, pointing to a more complex problem related to iron homeostatic regulation and additional factors such as chronic inflammatory status. This review explores our current understanding of iron homeostasis in cancer, shedding light on the modulatory role of hepcidin in intestinal iron absorption, iron recycling, mobilization from liver deposits, and inducible regulators by infections and inflammation. The underlying relationship between CRA and systemic low-grade inflammation will be discussed, and an integrated multitarget approach based on nutrition and exercise to improve iron utilization by reducing low-grade inflammation, modulating the immune response, and supporting antioxidant mechanisms will also be proposed. Indeed, a Mediterranean-based diet, nutritional supplements and exercise are suggested as potential individualized strategies and as a complementary approach to conventional CRA therapy.

Roflumilast Reduced the IL-18-Induced Inflammatory Response in Fibroblast-Like Synoviocytes (FLS)

Pro-inflammatory cytokines, such as the IL-18-induced inflammatory response and associated damage in fibroblast-like synoviocytes (FLS), play an important role in the pathogenesis of rheumatoid arthritis (RA). Roflumilast, an inhibitor of phosphodiesterase-4 (PDE-4), has been licensed for the treatment of chronic obstructive pulmonary disease (COPD). However, it is unknown whether roflumilast possesses a protective effect against the IL-18-induced inflammatory response in FLS. We found that roflumilast attenuated IL-18-induced oxidative stress by reducing the production of reactive oxygen species and malondialdehyde (MDA) in MH7A fibroblast-like synoviocytes (FLS). Additionally, roflumilast prevented IL-18-induced expressions and secretions of pro-inflammatory cytokines such as IL-6, IL-8, and TNF-α. Importantly, we found that roflumilast inhibited IL-18-induced expressions of chemokines such as CCL5, CXCL9, and CXCL10. Further, roflumilast inhibited the expression of extracellular matrix degradative enzymes, such as matrix metalloproteinase-3 (MMP-3) and MMP-13. Mechanistically, we found that roflumilast suppressed the activation of the transcriptional factor AP-1 and NF-κB. Our results suggest that roflumilast might be a potential therapeutic agent for the treatment of RA.

Cross-Talk between Diet-Associated Dysbiosis and Hand Osteoarthritis

Hand osteoarthritis (OA) is a degenerative joint disease which leads to pain and disability. Recent studies focus on the role of obesity and metabolic syndrome in inducing or worsening joint damage in hand OA patients, suggesting that chronic low-grade systemic inflammation may represent a possible linking factor. The gut microbiome has a crucial metabolic role which is fundamental for immune system development, among other important functions. Intestinal microbiota dysbiosis may favour metabolic syndrome and low-grade inflammation-two important components of hand OA onset and evolution. The aim of this narrative is to review the recent literature concerning the possible contribution of dysbiosis to hand OA onset and progression, and to discuss the importance of gut dysbiosis on general health and disease.

Ideal food pyramid for patients with rheumatoid arthritis: A narrative review

Emerging literature suggests that diet plays an important modulatory role in rheumatoid arthritis (RA) because diet is an environmental factor that affects inflammation, antigen presentation, antioxidant defense mechanisms and gut microbiota. Patients with RA frequently ask their doctors about which diets to follow, and even in the absence of advice from their physicians, many patients are undertaking various dietary interventions. Given this background, the aim of this review is to evaluate the evidence to date regarding the ideal dietary approach for management of RA in order to reduce the counteracting inflammation, and to construct a food pyramid for patients with RA. The pyramid shows that carbohydrates should be consumed every day (3 portions of whole grains, preferably gluten free), together with fruits and vegetables (5 portions; among which fruit, berries and citrus fruit are to be preferred, and among the vegetables, green leafy ones.), light yogurt (125 ml), skim milk (200 ml), 1 glass (125 ml) of wine and extra virgin olive oil; weekly, fish (3 portions), white meat (3 portions), legumes (2 portions) eggs (2 portions), seasoned cheeses (2 portions), and red or processed meats (once a week). At the top of the pyramid, there are two pennants: one green means that subjects with RA need some personalized supplementation (vitamin D and omega 3) and one red means that there are some foods that are banned (salt and sugar). The food pyramid allows patients to easily figure out what to eat.

HLAs in Autoimmune Diseases: Dependable Diagnostic Biomarkers?

BACKGROUND

The process of antigen presentation to immune cells is an undeniable contributor to the pathogenesis of autoimmune diseases. Different studies have indicated several factors that are related to autoimmunity. Human Leukocyte Antigens (HLAs) are among such factors, which have a key role in autoimmunity because of their involvement in antigen presentation process.

METHODS

Relevant English language literature was searched and retrieved from Google Scholar search engine and PubMed database (1996-2018). The following keywords were used: "Human leukocyte antigen", "Behcet's syndrome", "Rheumatoid arthritis", "Systemic lupus erythematosus", "Type 1 diabetes", "Celiac Disease" and "Autoimmunity".

RESULTS

There is a strong association between HLA alleles and autoimmune diseases. For instance, HLA-B alleles and Behcet's syndrome are strongly correlated, and systemic lupus erythematosus and Type 1 diabetes are related to HLA-DQA1 and HLA-DQB1, respectively.

CONCLUSION

Association between numerous HLA alleles and autoimmune diseases may justify and rationalize their use as biomarkers as well as possible diagnostic laboratory parameters.

Polyphenols and Intestinal Permeability: Rationale and Future Perspectives

Increasing evidence links intestinal permeability (IP), a feature of the intestinal barrier, to several pathological or dysfunctional conditions. Several host and environmental factors, including dietary factors, can affect the maintenance of normal IP. In this regard, food bioactives, such as polyphenols, have been proposed as potential IP modulators, even if the mechanisms involved are not yet fully elucidated. The aim of the present paper is to provide a short overview of the main evidence from in vitro and in vivo studies supporting the role of polyphenols in modulating IP and briefly discuss future perspectives in this research area.

Design of an anti-inflammatory diet (ITIS diet) for patients with rheumatoid arthritis

Background

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that affects synovial joints, leading to inflammation, joint destruction, loss of function, and disability. Although recent pharmaceutical advances have improved treatment of RA, patients with RA often inquire about dietary interventions to improve RA symptoms, as they perceive rapid changes in their symptoms after consumption of certain foods. There is evidence that some ingredients have pro- or anti-inflammatory effects. In addition, recent literature has shown a link between diet and microbiome changes. Both diet and the gut microbiome are linked to circulating metabolites that may modulate inflammation. However, evidence of the effects of an anti-inflammatory and probiotic-rich diet in patients with RA is scarce. There is also a need for biological data to support its anti-inflammatory effects.

Methods

The main goal of this study is to delineate the design process for a diet tailored to our RA population. To achieve this goal, we collected information on diet, supplements, cooking methods, and intake of different ingredients for each patient. Different groups were interviewed, and their feedback was assessed to design a diet that incorporates suggested anti-inflammatory ingredients in a manner that was easy for patients to adopt based on their lifestyles and backgrounds.

Results

We designed a diet that includes a high intake of potential anti-inflammatory ingredients. Feedback from highly motivated patients was critical in constructing an anti-inflammatory diet (ITIS diet) with elevated adherence.

Conclusion

In order to tailor our diet, we surveyed our patients on several different parameters. We obtained important feedback on how feasible our ITIS diet is for RA patients. Using this feedback, we made minor improvements and finalized the design of the ITIS diet. This diet is being used in an on-going pilot study to determine their anti-inflammatory effect in pain and joint swelling in RA patients.

Trial registration

Not applicable.

Altered Gut Microbiota Composition Is Associated With Back Pain in Overweight and Obese Individuals

Background: Back pain is the leading cause of disability worldwide and is associated with obesity and chronic low-grade inflammation. Alterations in intestinal microbiota may contribute to the pathogenesis of back pain through metabolites affecting immune and inflammatory responses. Aims and Methods: We compared the gut microbiota composition in a cohort of 36 overweight or obese individuals with or without self-reported back pain in the preceding month. Participants were characterized for anthropometry; bone health; metabolic health; inflammation; dietary intake; and physical activity. Results: Demographic, clinical, biochemical characteristics, diet and physical activity were similar between participants with (n = 14) or without (n = 22) back pain. Individuals with back pain had a higher abundance of the genera Adlercreutzia (p = 0.0008; FDR = 0.027), Roseburia (p = 0.0098; FDR = 0.17), and Uncl. Christensenellaceae (p = 0.02; FDR = 0.27) than those without back pain. Adlercreutzia abundance remained higher in individuals with back pain in the past 2 weeks, 6 months, and 1 year. Adlercreutzia was positively correlated with BMI (rho = 0.35, p = 0.03), serum adipsin (rho = 0.33, p = 0.047), and serum leptin (rho = 0.38, p = 0.02). Conclusions: Our findings suggest that back pain is associated with altered gut microbiota composition, possibly through increased inflammation. Further studies delineating the underlying mechanisms may identify strategies for lowering Adlercreutzia abundance to treat back pain.

Deciphering crucial genes in coeliac disease by bioinformatics analysis

Coeliac disease (CD) is a chronic autoimmune disease that is characterized by malabsorption in sensitive individuals. CD is triggered by the ingestion of grains containing gluten. CD is concomitant with several other disorders, including dermatitis herpetiformis, selective IgA deficiency, thyroid disorders, diabetes mellitus, various connective tissue disorders, inflammatory bowel disease, and rheumatoid arthritis. The advent of high throughput technologies has provided a massive wealth of data which are processed in various omics scale fields. These approaches have revolutionized the medical research and monitoring of the biological systems. In this regard, omics scaled analyses of CD by Comparative Toxicogenomics Database (CTD), DISEASES, and GeneCards databases have retrieved 2656 CD associated genes. Amongst, 54 genes were assigned by Venn Diagram of the intersection to be shared by these 3 databases for CD. These common genes were subjected to further analysis and screening. The Enrich database, GeneMANIA, Cytoscape, and WebGestalt (WEB-based GEne SeT AnaLysis Toolkit) were employed for functional analysis. These analyses indicated that the obtained genes are mainly involved in the immune system and signalling pathways related to autoimmune diseases. The STAT1, ALB, IL10, IL2, IL4, IL17A, TGFB1, IL1B, IL6, TNF, IFNG hub genes were particularly indicated to have significant roles in CD. Functional analyses of these hub genes by GeneMANIA indicated that they are involved in immune systems regulation. Moreover, 25 out of 54 genes were identified to be seed genes by the WebGestalt database. Gene set analysis with GEO2R tool from Gene Expression Omnibus (GEO) showed that there were 15 significant genes in GSE76168, 29 significant genes in GSE87460, 12 significant genes in GSE87458, 9 significant genes in GSE87457, 3753 significant genes in GSE112102 and 1043 significant genes in GSE102991 with differential expression in coeliac patients compared to controls. The IRF1and STAT1 genes were common between the significant genes from GEO and the 54 CD related genes from three public databases. In the light these results, nine key genes, including IRF1, STAT1, IL17A, TGFB1, ALB, IL10, IL2, IL4, and IL1B, were identified to be associated with CD. These findings could be used to find novel diagnostic biomarkers, understand the pathology of disease, and devise more efficient treatments.

Effects of Anti-Cytokine Antibodies on Gut Barrier Function

Anti-cytokine antibodies are used in treating chronic inflammatory diseases and autoimmune diseases such as inflammatory bowel disease and rheumatic diseases. Patients with these diseases often have a compromised gut barrier function, suggesting that anti-cytokine antibodies may contribute to the re-establishment of gut barrier integrity, in addition to their immunomodulatory effects. This paper reviews the effects of anti-cytokine antibodies on gut barrier function and their mechanisms.

Micronutrients in autoimmune diseases: possible therapeutic benefits of zinc and vitamin D

A functional immune system is essential for healthy life. This is achieved by the coordinate activation and interaction of different immune cells. One should be aware that activation of the immune response is as important as its deactivation when the pathogens are cleared, as otherwise host tissue can be damaged up to life-threatening levels. Autoimmune diseases (AID) represent a phenomenon of immune cells attacking host cells and tissue. Five to eight percent of the world's population are currently affected by 80-100 AID. In recent years, the incidence has been constantly increasing, reaching alarmingly high numbers particularly for type 1 diabetes mellitus, Crohn's disease, rheumatoid arthritis, Sjogren's syndrome and multiple sclerosis. This indicates a higher societal burden of AID for the future. This article provides an overview of general concepts of triggers and underlying mechanisms leading to self-destruction. Lately, several original concepts of disease etiology were revised, and there is a variety of hypotheses on triggers, underlying mechanisms and preventive actions. This article concentrates on the importance of nutrition, especially zinc and vitamin D, for balancing the immune function. Homespun nutritional remedies seem to reenter today's therapeutic strategies. Current treatment approaches are largely symptomatic or suppress the immune system. However, recent studies reveal significant benefits of nutrition-related therapeutic approaches including prevention and treatment of established disease, which offer a cost-efficient and trigger-unspecific alternative addressing balancing rather than suppression of the immune system. Zinc and vitamin D are currently the best studied and most promising candidates for therapeutic intervention.

Gastrointestinal Manifestations of Rheumatological Diseases

Rheumatological diseases (RDs) represent a diverse group of diseases that are inherited or related to environmental factors. RDs frequently affect the gastrointestinal (GI) tract, and gastroenterologists are often asked to evaluate patients with symptoms thought to represent an underlying or coexisting RD. GI manifestations of RDs vary based on the organ involved as well as the extent and duration of involvement. Although most manifestations of RD are nonspecific and not life-threatening, the chronicity and severity of symptoms can be debilitating and may lead to serious injury. This narrative review discusses the most common RD encountered by gastroenterologists: systemic lupus erythematosus, systemic sclerosis (scleroderma), dermatomyositis/polymyositis, rheumatoid arthritis, Sjögren syndrome, overlap syndromes, mixed connective tissue disease, Ehlers-Danlos syndromes, and other vasculitides. Each section begins with a brief overview of the condition, followed by a discussion of the etiopathophysiology, physical examination findings, GI manifestations, diagnostic tools (i.e., serologic, imaging, endoscopic, and functional), and treatment options.

Inflammatory arthritis disrupts gut resolution mechanisms, promoting barrier breakdown by Porphyromonas gingivalis

Rheumatoid arthritis is linked with altered host immune responses and severe joint destruction. Recent evidence suggests that loss of gut homeostasis and barrier breach by pathobionts, including Porphyromonas gingivalis, may influence disease severity. The mechanism(s) leading to altered gut homeostasis and barrier breakdown in inflammatory arthritis are poorly understood. In the present study, we found a significant reduction in intestinal concentrations of several proresolving mediators during inflammatory arthritis, including downregulation of the gut-protective mediator resolvin D5n-3 DPA (RvD5n-3 DPA). This was linked with increased metabolism of RvD5n-3 DPA to its inactive 17-oxo metabolite. We also found downregulation of IL-10 expression in the gut of arthritic mice that was coupled with a reduction in IL-10 and IL-10 receptor (IL-10R) in lamina propria macrophages. These changes were linked with a decrease in the number of mucus-producing goblet cells and tight junction molecule expression in the intestinal epithelium of arthritic mice when compared with naive mice. P. gingivalis inoculation further downregulated intestinal RvD5n-3 DPA and Il-10 levels and the expression of gut tight junction proteins. RvD5n-3 DPA, but not its metabolite 17-oxo-RvD5n-3 DPA, increased the expression of both IL-10 and IL-10R in macrophages via the upregulation of the aryl hydrocarbon receptor agonist l-kynurenine. Administration of RvD5n-3 DPA to arthritic P. gingivalis-inoculated mice increased intestinal Il-10 expression, restored gut barrier function, and reduced joint inflammation. Together, these findings uncover mechanisms in the pathogenesis of rheumatoid arthritis, where disruption of the gut RvD5n-3 DPA-IL-10 axis weakens the gut barrier, which becomes permissive to the pathogenic actions of the pathobiont P. gingivalis.

'Preclinical' rheumatoid arthritis in patients with celiac disease: A cross-sectional study

Objective: Preclinical or latent RA is characterized by the presence of autoantibodies in the absence of clinical symptoms. The objective of this study was to identify the prevalence of preclinical RA in patients with Celiac disease in order to determine whether or not such individuals should be screened for RA based on the high-risk.

Method: A cross-sectional study was carried out on patients with celiac disease in a tertiary care center in Rawalpindi, Pakistan. After initial assessment, RA-autoantibody levels (Rheumatoid factor and anti-CCP) were checked. Descriptive analysis was performed on the data gathered.

Results: Sixteen patients with known celiac disease were identified to have positive rheumatoid factor and/or anti-CCP levels with an overall prevalence rate of 35%. This trend was significant for celiac patients having history of inflammatory arthritis and active celiac disease. No statistical significance was seen in baseline characteristics for categories of patients with positive rheumatoid factor versus with positive anti-CCP antibodies.

Conclusion: Patients with CD can be considered as a high-risk group based on the high prevalence rate of rheumatoid factor/anti-CCP positivity observed in this study and should be considered for further RA screening/preventive studies.

Abbreviations: RA = Rheumatoid arthritis; CD = Celiac disease; anti-CCP = anti-citrullinated cyclic peptide) antibodies; RF = Rheumatoid factor; GFD = Gluten-free diet

MMP3 is a reliable marker for disease activity, radiological monitoring, disease outcome predictability, and therapeutic response in rheumatoid arthritis

Matrix metalloproteinase-3 or MMP3 also known as stromelysin-1 is an enzyme that is actively involved in joint destruction in rheumatoid arthritis (RA) patients. Screening the last three decades, it appears that serum levels of MMP3 reflect positively RA disease activity, joint and bone injury, and radiological erosion and predict disease outcome and drug responsiveness as summarized in several publications reporting outcomes on more than 8000 patients with RA. MMP-3 monitoring should be embedded in the routine assessment and accompany therapeutic modalities, in personalized medical RA management.

A correlation between intestinal microbiota dysbiosis and osteoarthritis

Osteoarthritis (OA) is a degenerative disease of the articular cartilage, resulting in pain and total joint disability. Recent studies focused on the role of the metabolic syndrome in inducing or worsening joint damage suggest that chronic low-grade systemic inflammation may represent a possible linking factor. This finding supports the concept of a new phenotype of OA, a metabolic OA. The gut microbiome is fundamental for human physiology and immune system development, among the other important functions. Manipulation of the gut microbiome is considered an important topic for the individual health in different medical fields such as medical biology, nutrition, sports, preventive and rehabilitative medicine. Since intestinal microbiota dysbiosis is strongly associated with the pathogenesis of several metabolic and inflammatory diseases, it is conceivable that also the pathogenesis of OA might be related to it. However, the mechanisms and the contribution of intestinal microbiota metabolites in OA pathogenesis are still not clear. The aim of this narrative review is to review recent literature concerning the possible contribution of dysbiosis to OA onset and to discuss the importance of gut microbiome homeostasis maintenance for optimal general health preservation.

Autoimmunity in celiac disease: Extra-intestinal manifestations

Celiac disease is an autoimmune condition of the small intestine caused by prolamins in genetically susceptible individuals evoked by multiple environmental factors. The pathological luminal intricate eco-events produce multiple signals that irradiate the entire body, resulting in a plethora of extra-intestinal manifestations. Nutrients, dysbiosis, dysbiotic components and their mobilome, post-translational modification of naive proteins, inter-enterocyte's tight junction dysfunction resulting in a leaky gut, microbial lateral genetic transfer of virulent genes, the sensing network of the enteric nervous systems and the ensuing pro-inflammatory messengers are mutually orchestrating the autoimmune interplay. Genetic-environmental-luminal events-mucosal changes are driving centrifugally the remote organs autoimmunity, establishing extra-intestinal multi organ injury. Exploring the underlying intestinal eco-events, the sensing and the delivery pathways and mechanisms that induce the peripheral tissues' damages might unravel new therapeutical strategies to prevent and help the gluten affected patients.