The effect of salazosulfapyridine on the in vitro antibody production in murine spleen cells

Switching between Three Types of Mesalazine Formulation and Sulfasalazine in Patients with Active Ulcerative Colitis Who Have Already Received High-Dose Treatment with These Agents

BACKGROUND AND AIM

Oral mesalazine and sulfasalazine (SASP) are key drugs for treating ulcerative colitis (UC). The efficacy of switching from one of the several mesalazine formulations to another is largely unknown. This study assessed the efficacy of switching among three types of mesalazine formulation and SASP for UC therapy.

METHODS

UC patients receiving high-dose mesalazine/SASP who switched to other formulations due to disease activity were considered eligible. Efficacy was evaluated 2, 6, and 12 months after switching.

RESULTS

A total of 106 switches in 88 UC patients were analyzed. The efficacy at 2 months after switching was observed in 23/39 (59%) cases from any mesalazine formulation to SASP, in 18/55 (33%) cases from one mesalazine to another, and in 2/12 (17%) cases from SASP to any mesalazine formulation. Nine of 43 effective cases showed inefficacy or became intolerant post-switching. Delayed efficacy more than two months after switching was observed in four cases. Steroid-free remission was achieved in 42/106 (39%) cases-within 100 days in 35 of these cases (83%).

CONCLUSIONS

Switching from mesalazine to SASP was effective in more than half of cases. The efficacy of switching between mesalazine formulations was lower but may be worth attempting in clinical practice from a safety perspective.

Pediatric ulcerative colitis: a practical guide to management

Ulcerative colitis (UC) is a chronic inflammatory disorder of the gastrointestinal tract of unknown etiology that frequently presents in the pediatric population. The evaluation of pediatric UC involves excluding infection, and a colonoscopy that documents the clinical and histologic features of chronic colitis. Initial management of mild UC is typically with mesalamine therapy for induction and maintenance. Moderate UC is often initially treated with oral prednisone. Depending on disease severity and response to prednisone, maintenance options include mesalamine, mercaptopurine, azathioprine, infliximab, or adalimumab. Severe UC is typically treated with intravenous corticosteroids. Corticosteroid nonresponders should either undergo a colectomy or be treated with second-line medical rescue therapy (infliximab or calcineurin inhibitors). The severe UC patients who respond to medical rescue therapy can be maintained on infliximab or thiopurine, but 1-year remission rates for such patients are under 50 %. These medications are discussed in detail along with the initial work-up and a treatment algorithm.

Sulphasalazine inhibits human antigen-specific immune responses in vivo

OBJECTIVE

To study the effects of the antirheumatic drug sulphasalazine (SASP) on the immune system by analysing systemic and gut-associated immune responses.

METHODS

A total of 23 healthy volunteers were treated with either SASP or placebo for 5 weeks in a double-blind fashion and immunised 2 weeks after the initiation of treatment. Specific immune responses were triggered by subcutaneous immunisation with tetanus toxoid and by peroral immunisation with inactivated influenza vaccine. The effects of treatment on specific immunity to tetanus and influenza were evaluated by enzyme-linked immunospot assay quantifying the number of circulating specific and total antibody-producing cells (spot-forming cells (SFC)) at 6, 8 and 10 days after immunisation.

RESULTS

An immunosuppressive effect of SASP on systemic immune response was observed with a decrease in the total number of IgG-SFC, IgG anti-tetanus SFC and IgG anti-tetanus antibody levels in serum. SASP also exerted an immunosuppressive effect on the mucosa-associated immune system as seen from its down-regulating effect on the total number of circulating IgA SFC.

CONCLUSIONS

These data show firstly that SASP exerts an immunosuppressive effect on defined immune responses to immunisation in vivo, and secondly that both mucosa-associated and systemic immunity are affected by SASP treatment.

Mechanistic studies on genotoxicity and carcinogenicity of salicylazosulfapyridine an anti-inflammatory medicine

Salicylazosulfapyridine (SASP), which has been in clinical use for over 50 years, was reported by the National Toxicology Program to increase rat (F344 strain) urinary bladder and mouse (B6C3F1 hybrid) liver tumours under ad libitum (AL) feeding conditions, while under a feed restriction (FR) regimen, these tumours were not increased. The present investigations were undertaken to assess the implications of these results for the safety of SASP in humans. SASP and its 2 major metabolites, 5-aminosalicylic acid (ASA) and sulfapyridine (SP) were tested for in vivo induction of micronuclei in mouse bone marrow cells with or without prefolic treatment and for in vivo formation of DNA adducts in rat and mouse liver and urinary bladder. None exhibited mutagenicity or DNA reactivity. SASP and SP have induced sister chromatid exchanges and micronuclei (MN) in cultured human lymphocytes in the absence of liver activation enzymes and in B6C3F1 mice (but not in rats) MN in bone marrow and peripheral RBC. Treatment with folate reduces the frequency of MN. Perhaps the short (28 days) RBC lifespan in mouse underlies the sensitivity of this species. Thus, SASP without folate supplementation is an aneuploidogen. In a 2-year study in AL fed SASP-treated (high dose 337.5 mg/kg) rats, urinary pH was increased and urinary specific gravity was reduced at 60 weeks. At the end, this SASP group showed urothelial hyperplasia and papillomas in the urinary bladders of male rats primarily. In the FR high dose SASP group, the hyperplasia was reduced from 82% to 14%. At the end of 2 years, the incidence of multi-organ leukemia was reduced in both AL and FR high dose SASP groups. Thus, SASP caused intraluminal bladder changes in the rat (especially males) consisting of chronic urothelial stimulation, concretions, hyperplasia which resulted in neoplasia. In the mouse, because of species differences in liver ratios (mouse > rat) and, increasing (3 times higher) liver perfusion in the mouse, compared to the rat, there was hepatocellular toxicity and resulting preneoplasia and neoplasia within 2 years. These findings occurred in all AL SASP groups (flat curve without dose response); but were reduced under FR conditions. In this species, the multiorgan lymphoma incidence was reduced in both AL and FR high dose SASP groups. Thus, SASP and its major metabolites are not genotoxic. Folate deficiency associated with SASP administration is probably responsible for aneuploidy in lymphocytes and erythrocytes. SASP does not induce neoplasia directly in either livers, urinary bladders or other organs. Accordingly, SASP is judged to pose no carcinogenic risk to humans.

Effects of antirheumatic agents on cytokines

A review of the literature concerning the effects of traditional antirheumatic drugs on cytokines and the cytokine and anticytokine approaches already used in the therapy of rheumatoid arthritis (RA) is presented. Many antirheumatic drugs are capable of cytokine modulation in vitro. Corticosteroids inhibit the transcription of a broad spectrum of genes including those encoding monocyte, T cell-derived cytokines and several hemopoietic growth factors, whereas drugs such as cyclosporin A and D-penicillamine interfere with T cell activation more specifically by suppressing interleukin 2 (IL-2) production. The in vivo effects of drug therapy on cytokines in RA patients are less well established. Gold compounds reduce circulating IL-6 levels and the expression of monocyte-derived cytokines, such as IL-1, tumor necrosis factor (TNF), and IL-6, in the rheumatoid synovium. Decreases in circulating IL-6, soluble IL-2 (sIL-2R), and TNF receptors and in synovial fluid IL-1 levels have been reported with methotrexate. Reductions in circulating IL-6 and sIL-2R concentrations have also been observed with cyclosporin and corticosteroids, whereas azathioprine reduces IL-6 but not sIL-2R. Studies on sulfasalazine are conflicting and the in vivo effects of D-penicillamine and antimalarials have not been studied yet. Interferon gamma therapy is not effective in RA but may prove a useful antifibrotic for systemic sclerosis. Colony stimulating factors improve the granulocytopenia associated with Felty's syndrome or drug toxicities but can induce arthritis flares and should be reserved to treat infectious complications. Promising results are being obtained with selective antagonism of TNF and IL-1 in RA, and combinations of anticytokine strategies with traditional antirheumatic drugs have been already envisaged. These should preferably be based in a broader knowledge of the effects of antirheumatic agents on the cytokine network.

Crohn's disease and multiple sclerosis: a single case report

A case of the association of multiple sclerosis and Crohn's disease in a 47 year old patient is reported. A possible relationship between these two diseases has been widely documented, both sporadically and at a familial level. Albeit in the absence of precise experimental data, it is legitimate to presume that the two diseases share common pathogenetic traits.

Comparison of the effect of oral sulphasalazine, sulphapyridine and 5-amino-salicylic acid on the in vivo antibody response to oral and systemic antigen

1. Mice, whose drinking water contained sulphasalazine, sulphapyridine or 5-amino-salicylic acid, received an antigenic challenge by cholera toxin administered either orally or systemically. 2. Sulphasalazine treated mice made less specific antibody of IgA class provided the antigen also was administered orally (P = 0.009 for days 7-28). When the antigen was administered systemically, there was a vigorous anti-cholera toxin antibody response of IgG class, and a lesser IgM but only a weak IgA response. The effect of sulphasalazine in this case was confined to the IgG response, which was significantly suppressed on day 28 (P = 0.008). 3. Sulphapyridine and 5-amino salicylic acid had no significant effect on the anti-cholera toxin (CT) responses of all three classes. 4. It therefore appears that in this model, only sulphasalazine is capable of influencing the humoral immune system, the antibody class affected depending on the route of entry of antigen. This may have implications for conditions such as rheumatoid arthritis and chronic inflammatory bowel disease, for which sulphasalazine has been found useful.

Inhibition of proliferative responses and interleukin 2 productions by salazosulfapyridine and its metabolites

Mixed lymphocytes reactions (MLR) and concanavalin A (Con A)- or phytohemagglutinin (PHA)-stimulated proliferative responses were dose-dependently inhibited by salazosulfapyridine (SASP) and cyclosporin A (CsA) in the concentration ranges of 1 x 10(-5) -5 x 10(-4) M and 10-1000 ng/ml, respectively. Such a significant inhibition was not observed with metabolites of SASP, sulfapyridine (SP) and 5-aminosalicylic acid (5-ASA). In addition, SASP and CsA inhibited the production of interleukin 2 (IL-2) from splenocytes in these experiments. The inhibitory effect of CsA on IL-2 production practically correlated with that on proliferative responses, whereas SASP showed a less marked inhibitory effect on IL-2 production than on proliferative responses. Neither SP nor 5-ASA inhibited the IL-2 production. In the Con A-induced proliferative response, SASP showed a full inhibition even when added after 4-8 hr of culture, but CsA did not. The splenocytes that were pulsed with Con A for 4 hr could proliferate in response to Con A-supernatant or purified IL-2. CsA exhibited the inhibitory activity only when present during the time of Con A-pulsing, while SASP acted on the subsequent stage of the response, exerting its inhibitory effect. These findings suggest that SASP down-regulates the immune response by a mechanism apparently distinct from that of CsA.