Influence of anti-rheumatic drugs on gut permeability and on the gut associated lymphoid tissue

Haptoglobin and Its Related Protein, Zonulin-What Is Their Role in Spondyloarthropathy?

Haptoglobin (Hp) is an acute phase protein which supports the immune response and protects tissues from free radicals. Its concentration correlates with disease activity in spondyloarthropathies (SpAs). The Hp polymorphism determines the functional differences between Hp1 and Hp2 protein products. The role of the Hp polymorphism has been demonstrated in many diseases. In particular, the Hp 2-2 phenotype has been associated with the unfavorable course of some inflammatory and autoimmune disorders. Its potential role in modulating the immune system in SpA is still unknown. This article contains pathophysiological considerations on the potential relationship between Hp, its polymorphism and SpA.

Self-reported food intolerance and mucosal reactivity after rectal food protein challenge in patients with rheumatoid arthritis

OBJECTIVES

A dietary link to rheumatoid arthritis (RA) has been suspected and an influence on arthritic symptoms by different diets has been reported. Our primary aim was to record the self-experienced adverse food reactions in patients with RA. A secondary aim was to relate self-experienced adverse reactions to dairy produce and wheat to the local mucosal reactivity observed after rectal challenge with cow's milk protein (CM) and wheat gluten.

METHODS

A questionnaire about self-experienced adverse reaction to food was sent to 347 RA patients. Rectal challenge with CM and gluten was performed in 27 of these patients and in healthy controls (n = 18). After a 15-h challenge the mucosal production of nitric oxide (NO) and the mucosal release of myeloperoxidase (MPO) and eosinophil cationic protein (ECP) were measured by using the mucosal patch technique.

RESULTS

Twenty-seven per cent of the RA patients reported food intolerance (FI) to various foods, and in particular to CM, meat, and wheat gluten. Strong mucosal reactivity to CM was observed in 11% of the patients. Moderately increased mucosal reactivity to CM and gluten was found in 22% and 33%, respectively, of the patients. No relationship was found between self-experienced adverse reactions to CM or gluten and mucosal reactivity to these proteins.

CONCLUSIONS

Perceived FI is reported frequently by RA patients, with a prevalence similar to that reported previously in the general population. Mucosal reactivity to CM and gluten is seen in a minor fraction of RA patients and is not related to the frequently perceived intolerance to these proteins.

Host factors in amniotic fluid and breast milk that contribute to gut maturation

The gut represents a complex organ system with regional differences, which reflect selective digestive and absorptive functions that change constantly in response to bodily requirements and the outside milieu. As a barrier to the external environment, gut epithelium must be renewed rapidly and repeatedly. Growth and renewal of gut epithelial cells is dependent on controlled cell stimulation and proliferation by a number of signaling processes and agents, including gut peptides-both endogenous and exogenous sources. This cascade of events begins during fetal development; with the ingestion of amniotic fluid, this process is enhanced and continued during infancy and early childhood through the ingestion of human milk. Events influenced by amniotic fluid during fetal development and those influenced by human milk that unfold after birth and early childhood to render the gut mature are presented.

The incidence of Proteus mirabilis infection increases in patients on treatment but does not trigger disease activity

The aim of this study is to determine whether treatment increases the levels of anti-Proteus antibodies (APA) in patients with rheumatoid arthritis (RA). The blood samples of 32 patients suffering from RA who were recruited in our previous study and continued to participate in our follow-up study were collected after 1 year. Their first and follow-up samples were analysed for the presence of IgG isotype and total immunoglobulins (IgG+IgA+IgM) against Proteus mirabalis (PM) using enzyme-linked immunosorbent assay with two kinds of antigen preparations: whole bacteria and sodium dodecyl sulphate (SDS) lysed bacterial extract. All patients were treated with methotrexate and hydroxychloroquine with adequate dose of non-steroidal anti-inflammatory drug. After 1 year, 11 patients were in clinical remission [erythrocyte sedimentation rate (ESR) less than 30 mm/h and C-reactive protein (CRP) less than or equal to 10 mg/l], while the rest of the 21 were in the state of active disease. Correlation and Student's t test were used for statistical analysis. APA titres were significantly elevated in patients after 1 year of therapy. However, the rise was not different between patients who were in clinical remission and those in the state of active disease. APA titre increases in the treatment of RA, and the probable mechanisms are discussed.

A study of the combined effect of the CLDN5 locus and the genes for the phospholipid metabolism pathway in schizophrenia

The present study attempts to test the combined effect of the CLDN5 gene and those for the phospholipid metabolism pathway, including PTGS1, PTGS2, PLA2G4A and PLA2G4C. We detected five single nucleotide polymorphisms (SNPs) present in these genes among 131 British family trios of schizophrenic patients. The transmission disequilibrium test (TDT) showed that BanI-SNP located in the 5'-flanking region of the PLA2G4A gene was associated with schizophrenia (chi(2) = 5.16, P = 0.023) although the others failed to show such allelic associations. The global P-value was 0.150 for 1000 permutations with the TDT analysis. The conditioning on genotype test, but not on allele test, revealed a strong association for the combination of the CLDN5 gene with the PLA2G4A gene (chi(2) = 10.17, df = 2, P = 0.006). The present results suggest that the PLA2G4A locus may be involved in schizophrenia and its combination with the CLDN5 gene may increase further the risk for the illness.

Determining small bowel integrity following drug treatment

Intestinal integrity is maintained by a delicate balance between mucosal defence and luminal aggressors that cause damage if exposed to the mucosa. The intestinal barrier function appears to be the gatekeeper for controlling this balance. It is becoming increasingly clear that if the intestinal barrier is disrupted the consequences are low grade intestinal inflammation which carry with it the risk of significant blood and protein loss both of which may cause clinical management problems. We review the strength and weaknesses of methods for assessing small bowel function that are useful for assessing drug-induced intestinal toxicity. There are a number of imaging methods for assessing intestinal integrity but these do not provide functional information. Intestinal permeability measurements have been optimized for specificity and there are now ways of measuring intestinal permeability regionally, but marker analyses continue to be cumbersome. Recent developments of faecal inflammatory markers make it a matter of routine to assess this in any routine chemical pathology laboratory. Bleeding, protein loss and other complications of inflammation can also be measured with good specificity, but again the methods are cumbersome. Using a combination of functional and imaging techniques it is now possible to characterize and define with precision, the small bowel side-effects of drugs, the best example being the small bowel side-effects of nonsteroidal anti-inflammatory drugs (NSAIDs).

Modulation of immune function by dietary lectins in rheumatoid arthritis

Despite the almost universal clinical observation that inflammation of the gut is frequently associated with inflammation of the joints and vice versa, the nature of this relationship remains elusive. In the present review, we provide evidence for how the interaction of dietary lectins with enterocytes and lymphocytes may facilitate the translocation of both dietary and gut-derived pathogenic antigens to peripheral tissues, which in turn causes persistent peripheral antigenic stimulation. In genetically susceptible individuals, this antigenic stimulation may ultimately result in the expression of overt rheumatoid arthritis (RA) via molecular mimicry, a process whereby foreign peptides, similar in structure to endogenous peptides, may cause antibodies or T-lymphocytes to cross-react with both foreign and endogenous peptides and thereby break immunological tolerance. By eliminating dietary elements, particularly lectins, which adversely influence both enterocyte and lymphocyte structure and function, it is proposed that the peripheral antigenic stimulus (both pathogenic and dietary) will be reduced and thereby result in a diminution of disease symptoms in certain patients with RA.

Review article: Pathophysiology of the intestinal mucosa in inflammatory bowel disease and arthritis: similarities and dissimilarities in clinical findings

Although apparently dissimilar in both structure and function, the gut and locomotor system are linked by a number of clinical syndromes in which both are involved. In inflammatory bowel disease, intestinal mucosal inflammation is the primary problem, but may be associated with both axial and peripheral arthropathies. In the seronegative spondyloarthropathies the primary problem is in the locomotor system, but intestinal abnormalities may also be present. In addition, non-steroidal anti-inflammatory drugs used in their treatment, may cause a distinct enteropathy which may be confused with the disease-related intestinal abnormalities. The clinical, histological and genetic features of these conditions are examined in order to assess their relationship and the central role of the intestinal mucosa in their pathogenesis.