Effects of sulphasalazine and disodium azodisalicylate on colonic PGE2 concentrations determined by equilibrium in vivo dialysis of faeces in patients with ulcerative colitis and healthy controls.

The role of arachidonic acid metabolites and the mode of action of 5-aminosalicylic acid, the active moiety of sulphasalazine and disodium azodisalicylate, in ulcerative colitis remain obscure. Therefore, experiments were performed in which the effects of medication on immunoreactive prostaglandin (PG) E2 concentrations in free faecal water were assessed using the equilibrium in vivo dialysis of faeces. Colonic PGE2 concentrations in patients with active ulcerative colitis (n = 11) ranged from 2035-18,000 pg/ml to be compared with a range of 103-188 pg/ml in healthy volunteers (n = 10; p less than 0.001). In all healthy volunteers PGE2 concentrations decreased slightly (p less than 0.05) after disodium azodisalicylate intake 2 g/day, whereas low dose disodium azodisalicylate (0.25 g/day) caused no change. In patients with ulcerative colitis in complete clinical, sigmoidoscopic, and histologic remission withdrawal of sulphasalazine (2 g/day; n = 6) increased PGE2 concentrations to values above normal levels (p less than 0.05) which returned to pretrial values (p less than 0.05) on disodium azodisalicylate (2 g/day; n = 7). In conclusion, increased PGE2 in free faecal water indicates an abnormality in the colonic mucosa, even in the absence of conventional signs of inflammation. We could not confirm the hypothesis that sulphasalazine and 5-aminosalicylic acid exert their therapeutic effect through promotion of endogenous cytoprotective prostaglandins. In contrast, the observation that raised PGE2 concentrations were normalised by disodium azodisalicylate in patients with inactive ulcerative colitis suggests that subclinical disease activity was decreased by 5-aminosalicylic acid.     

Longterm olsalazine treatment: pharmacokinetics, tolerance and effects on local eicosanoid formation in ulcerative colitis and Crohn's colitis.

To examine pharmacokinetics and tolerance of long term administration of olsalazine (azodisalicylate), increasing doses of the drug were given for one year to 31 patients with ulcerative colitis (UC) and nine patients with Crohn's colitis (CC), refractory to, or intolerant of sulphasalazine, until sustained remission was obtained or a maximum of 4 g/day was reached. Colonic drug metabolism was studied by equilibrium in vivo dialysis of faeces. Complete azoreduction occurred in most cases. Concentrations of 5-aminosalicylic acid, but not N-acetyl-5-aminosalicylic acid, in faecal dialysates increased dose dependently. Serum concentrations disclosed no cumulation in the long term and olsalazine was well tolerated, although loose stools occurred transiently in some patients with extensive disease: this was associated with a larger proportion of unsplit olsalazine in the faecal dialysates. Patients with ulcerative colitis having a high prostaglandin E2 concentration (greater than ng/ml) determined by equilibrium dialysis of rectum, were less likely to benefit from treatment. Olsalazine is a very effective means of delivery of 5-aminosalicylic acid to the colonic mucosa in active disease. Use of the drug in controlled trials may be considered safe even in prolonged high dosage.     

Rectal mucosal prostaglandin E2 release and its relation to disease activity, electrical potential difference, and treatment in ulcerative colitis.

In vivo rectal dialysis was used to study rectal mucosal release of immunoreactive prostaglandin E2-like material and its relation to disease activity, rectal electrical potential difference (PD), and treatment in 24 patients with ulcerative colitis. In untreated colitics in remission and in relapse, median values for apparent mucosal prostaglandin E2 (PGE2) release were increased three-fold (P < 0.05) and 13-fold (P < 0.002) respectively over that found in control subjects. In patients in remission during treatment with sulphasalazine and/or corticosteroids, median apparent PGE2 release was similar to that of controls, but in colitics in relapse, despite treatment, it was greatly increased (P< 0.002). Ulcerative colitis in relapse was associated with a significant reduction in rectal PD(P < 0.002); in patients with quiescent ulcerative colitis, a smaller reduction was found (P < 0.05). In nine patients studied serially before and during treatment, there were associations between changes in disease activity assessed sigmoidoscopically, in PD and in apparent mucosal PGE2 release. Furthermore, rectal mucosal PGE2 release and PD were linearly correlated (P < 0.01). These findings indicate that mucosal PGE2 release is markedly enhanced in active ulcerative colitis, and they confirm the value of rectal PD as a guide to disease activity. In addition, they suggest that rectal dialysis may be a useful way of studying rectal prostaglandin metabolism in man.     

Effect of azodisal sodium and sulphasalazine on ileostomy output of fluid and PGE2 and PGF2 alpha in subjects with a permanent ileostomy.

Azodisal sodium is a highly effective means of oral delivery of 5-amino-salicylic acid to the colonic mucosa. Administration of this drug to patients intolerant of sulphasalazine, however, occasionally results in liquid stools. In preliminary experiments, which comprised 10 healthy volunteers treated with colectomy for ulcerative colitis, ileostomy fluid output increased (p less than 0.001) during oral intake of azodisal sodium (1 g/day). In a double blind, placebo controlled crossover study, comprising eight similar volunteers, ileostomy fluid output increased (p less than 0.05) in a dose related manner during intake of azodisal sodium (1 g/day vs 2 g/day) compared with placebo or sulphasalazine (2 g/day). Concentrations of prostaglandin (PG)F2 alpha in free ileal water determined by equilibrium in vivo dialysis of ileostomy contents decreased (p less than 0.05) during intake of azodisal sodium (2 g/day), whereas concentrations of PGE2 and the output of PGE2, PGF2 alpha, and 'PGE2 + PGF2 alpha' remained unchanged. Thus increased formation of PGs is apparently not the cause of increased ileostomy fluid output associated with azodisalicylate intake.     

The effect of sulphasalazine withdrawal on rectal mucosal function and prostaglandin E2 release in inactive ulcerative colitis

We have used in vivo rectal dialysis to assess mucosal prostaglandin E2 (PGE2) release and water and electrolyte transport before and 2 weeks after withdrawal of oral sulphasalazine in eight patients with inactive ulcerative colitis. Although rectal mucosal PGE2 release was unaffected by withdrawal of sulphasalazine, significant reductions in mucosal potential difference (P less than 0.01) and net absorption of water (P less than 0.05), sodium (P less than 0.05), and chloride occurred (P less than 0.05). Clinical assessment showed no change in disease activity. Sulphasalazine withdrawal thus has a detrimental effect on large-intestinal salt and water transport, which does not appear to be mediated through changes in net mucosal prostaglandin production.     

Circulating cytokine levels in patients with rheumatoid arthritis: results of a double blind trial with sulphasalazine.

Interleukin 1 (IL-1), IL-6, and tumour necrosis factor (TNF) alpha are pleiotropic cytokines produced predominantly by macrophages which have been implicated in the pathogenesis of rheumatoid arthritis (RA). Sulphasalazine has been shown to have disease modifying properties and to inhibit the production of cytokines in vitro. To evaluate the effect of sulphasalazine on cytokine production in vivo, serum cytokine levels were measured in a group of patients with RA entered into a randomised controlled trial. Serum levels of IL-1 alpha, IL-1 beta, IL-6, and TNF alpha were measured at baseline and at two monthly intervals for six months in 17 patients receiving sulphasalazine and in 22 patients treated with placebo. The two groups of patients had a similar age and sex distribution, had had RA for less than a year, had no joint erosions, and had not been treated previously with any other disease modifying drugs. In the 39 patients studied IL-1 alpha was detected (> 0.1 ng/ml) at baseline in 14 patients (median 0.24 ng/ml), IL-1 beta in 25 patients (median 1.0 ng/ml), TNF alpha in 27 patients (median 1.2 ng/ml), and IL-6 in 33 patients (median 0.44 ng/ml). In the group treated with sulphasalazine there was a progressive and significant decline in serum IL-1 alpha, IL-1 beta, and TNF alpha levels over the six month period (median levels at six months were < 0.1, 0.12, and 0.44 ng/ml respectively). Interleukin 6 levels were significantly reduced only at the four month time point (median level of 0.23 ng/ml). These reductions were associated with improvements in clinical and laboratory measures of disease activity. In contrast patients receiving the placebo showed no changes in serum cytokine levels and no improvement in clinical and laboratory indices of disease activity. These results suggest that sulphasalazine may exert its disease modifying effect partly by suppressing cytokine production in vivo.     

Comparative trial of sulphasalazine and oral sodium cromoglycate in the maintenance of remission in ulcerative colitis.

Patients with ulcerative colitis in remission were randomly allocated to treatment with sulphasalazine (2 g/day) or oral sodium cromoglycate (160 mg/day or 2 g/day), and the relapse rates in these treatment groups were compared during continued treatment for one year. The percentage cumulative relapse rate after 12 months' treatment was 30% in the 33 patients treated with sulphasalazine compared with 71% in the 25 treated with high dose sodium cromoglycate, a highly significant difference (P less than 0.01). Patients allocated low dose sodium cromoglycate were only treated for a maximum of six months, and the relapse rate in these 12 patients was similar to that in patients on the high dose. These results suggest that oral sodium cromoglycate is considerably less effective than sulphasalazine in maintaining remission, and by analogy with results in other trials may be no more effective than placebo tablets.     

Azodisalicylate (Olsalazine) in the treatment of active ulcerative colitis. A placebo controlled clinical trial and assessment of drug disposition

Abstract The efficacy, safety and disposition of azodisalicylate, (ADS, Olsalazine) was assessed in patients with left-sided ulcerative colitis (UC) or proctitis in a double-blind placebo controlled trial. Thirty patients with a mild-to-moderate attack of UC were randomly allocated to ADS capsules 1 g (b.d.) or placebo for 6 weeks; other therapy was ceased. Patients were reviewed weekly and plasma, urine and faecal concentrations of ADS and its metabolites were determined by high performance liquid chromatography (HPLC). Sigmoidoscopy and biopsy were repeated at 6 weeks.
Four patients receiving placebo and two receiving ADS were withdrawn because of diarrhoea. Five patients known to be allergic to sulphasalazine had no adverse reactions to ADS. Good clinical response was found in six patients receiving ADS and in two receiving placebo ( P = 0.11). Improvement in sigmoidoscopic findings and histological appearance of rectal biopsies was also seen more frequently in ADS-treated patients. Plasma concentrations of ADS were significantly higher in patients who improved. Faecal ADS, 5-ASA and acetyl-5-ASA varied widely and showed no correlation with response. ADS showed an advantage over placebo which needs to be confirmed by further studies; it was safe in sulphasalazine-sensitive patients but appeared to cause watery diarrhoea in two patients.     

Comparison of delayed release 5 aminosalicylic acid (mesalazine) and sulphasalazine in the treatment of mild to moderate ulcerative colitis relapse.

Oral formulations of 5-aminosalicylic acid (mesalazine) appear less toxic than sulphasalazine. We have therefore compared sulphasalazine, low dose mesalazine and high dose mesalazine in the treatment of mild to moderate relapse of ulcerative colitis. Sixty one patients (32 men, aged 20-78 years) were randomly allocated to sulphasalazine 2 g daily, mesalazine 800 mg daily, or mesalazine 2.4 g daily in a double blind, double dummy, four week trial. Groups were comparable for age, sex, extent of disease, and pretrial sulphasalazine intake. Four patients were unable to complete the study because of treatment failure (two taking sulphasalazine and two high dose mesalazine). A further two patients taking sulphasalazine developed side effects necessitating withdrawal. Within treatment comparisons revealed significant improvement of: sigmoidoscopic grade in the sulphasalazine group; rectal bleeding, sigmoidoscopic and histological grade in the low dose mesalazine group; stool frequency, rectal bleeding and sigmoidoscopic grade in the high dose mesalazine group. Greater improvement in rectal bleeding (p less than 0.05) and sigmoidoscopic appearances (p less than 0.05) occurred in patients taking high dose mesalazine than in those taking sulphasalazine. In two patients taking high dose mesalazine minor rises of plasma creatinine concentrations occurred, suggesting the need to monitor renal function.     

In vivo profiles of eicosanoids in ulcerative colitis, Crohn's colitis, and Clostridium difficile colitis

To compare the local release of arachidonic acid metabolites in inflammatory diarrheal disease, in vivo equilibrium dialysis of the rectum was done in consecutive untreated patients with ulcerative colitis (n = 20), Crohn's colitis (n = 10), and Clostridium difficile colitis (n = 7). All patients had endoscopically proven rectal inflammation. Eicosanoid profiles were determined in rectal dialysates by radioimmunoassay after preliminary purification. Concentrations of prostaglandin E2, prostaglandin F2 alpha, and thromboxane B2, but not 6-keto-prostaglandin F1 alpha, were raised in all groups and compared with healthy controls. The highest levels within each group were obtained in patients with widespread epithelial damage, as judged by endoscopy. In patients with ulcerative colitis, an extreme rise in prostaglandin E2 and thromboxane B2 were observed. Similarly, concentrations of leukotriene B4 were substantially increased in ulcerative colitis, but in Crohn's colitis and Clostridium difficile colitis only those patients with rectal ulcerations showed elevations. These findings probably reflect more severe tissue damages in ulcerative colitis, but differences between disease groups in cell-to-cell interaction may also contribute. The data suggest, therefore, that therapeutic inhibition of lipoxygenase pathways may prove more effective in ulcerative colitis than in Crohn's disease.     

Measurement of prostaglandin E2 in interstitial fluid from the dog stomach after feeding and indomethacin

The purpose of the study was to develop a method for collecting interstitial fluid bathing the stomach tissues in which prostaglandins could be measured. Hollow dialysis fibers attached at the ends to Silastic tubes were surgically implanted into the submucosa of the gastric fundus and antrum of dogs. The Silastic tubes were exteriorized through the body wall. After full recovery from surgery, the fibers were filled with 5% bovine serum albumin in isotonic saline that was replaced at 5-min intervals. Prostaglandin E2 was measured in the dialysate by radioimmunoassay. In 6 dogs, feeding significantly stimulated the release of prostaglandin E2 into the fundic interstitial fluid from 5.3 +/- 0.6 ng X ml-1 to 12.1 +/- 1.6 ng X ml-1 (p less than 0.01) but had no effect on antral levels. In 4 dogs, indomethacin (0.01, 0.1, 1.0, and 10.0 ng X kg-1, i.v.) caused a dose-dependent depression in prostaglandin E2 levels in interstitial fluid of the fundus and antrum. In 4 other dogs, indomethacin depressed the ex vivo generation of prostaglandin E2 in biopsy specimens of the fundus and antrum. These results validate the technique of interstitial fluid dialysis and suggest that it is a powerful method for examining the secretion of locally acting substances in the stomach of conscious animals.     

In vivo rectal inflammatory mediator changes with radiotherapy to the pelvis.

In vivo changes in the rectal values of eicosanoid inflammatory mediators induced by pelvic radiotherapy were measured to study the pathophysiology of the early radiation bowel reaction. Ten patients having pelvic radiotherapy, aged 57 to 78, had rectal dialysis. Values of the eicosanoids leukotriene B4 (LTB4), thromboxane B2 (TXB2), and prostaglandin E2 (PGE2) were measured before radiotherapy, at the end of radiotherapy, and at least four weeks after radiotherapy. Values of LTB4 rose with radiotherapy from 0.21 ng.ml-1 (median) to 1.14 ng.ml-1 (p = 0.012); PGE2 rose from 0.60 ng.ml-1 to 1.58 ng.ml-1 (p = 0.038), and TXB2 rose from 0.365 ng.ml-1 to 1.6 ng.ml-1 (p = 0.005). The rise in eicosanoid inflammatory mediators may have an important role in the pathophysiology of the early radiation bowel reaction.     

Effects of topical 5-aminosalicylic acid and prednisolone on prostaglandin E2 and leukotriene B4 levels determined by equilibrium in vivo dialysis of rectum in relapsing ulcerative colitis

To determine the influence of inflammation and topical treatment with 5-aminosalicylic acid or prednisolone on arachidonic acid metabolism in vivo, we carried out a double-blind controlled study on the release of prostaglandin E2 and leukotriene B4 to the rectal lumen in 24 consecutive patients with proven distally located ulcerative colitis. Before and at days 15 and 29 a dialysis bag was placed in the emptied rectum for 4 h prior to assessing clinical, endoscopic, and histologic disease activity. A single enema was given daily at bedtime (1 g 5-aminosalicylic acid or 25 mg prednisolone) until complete remission or for a maximum of 4 wk. Clinical and endoscopic remission was obtained in 16 (7 on 5-aminosalicylic acid) and 11 (3 on 5-aminosalicylic acid) patients, respectively. Luminal concentrations of prostaglandin E2 and leukotriene B4 were positively correlated to disease activity and significantly decreased among the prednisolone-treated patients. In both treatment groups a decrease toward normal levels occurred in patients responding to therapy. In retrospect, the pretreatment prostaglandin E2 and leukotriene B4 levels were significantly higher in patients not responding to therapy than in those improving during treatment. In conclusion, luminal prostaglandin E2 and leukotriene B4 levels may prove more useful predictors of the outcome of treatment in relapsing ulcerative colitis than clinical indices of disease activity.     

Effect of misoprostol on concentrations of prostaglandins in synovial fluid.

The effect of misoprostol, a synthetic analogue of prostaglandin E, on prostaglandin concentrations in synovial fluids was investigated in a randomised placebo controlled, double blind study. The synovial fluid concentrations of prostaglandin E1, 6-keto-prostaglandin F1 alpha, and thromboxane B2 were measured at the beginning and end of a 24 hour period in 25 patients with effusions of the knee joint. During this period the patients were treated with diclofenac (50 mg every eight hours) and either misoprostol (400 micrograms) or placebo every 12 hours. The concentrations of prostaglandin E and 6-keto-prostaglandin F1 alpha were not significantly altered during treatment. There was an unexpected significant reduction in thromboxane B2 concentrations in the group treated with misoprostol (within group analysis). Although the mean concentration with misoprostol was about half the mean concentration with placebo, this difference was not statistically significant in the between group analysis. These results indicate that misoprostol is unlikely to exert a proinflammatory effect or to interfere with the prostaglandin mediated effects of non-steroidal anti-inflammatory drugs. The significant decrease in thromboxane B2 concentrations in the misoprostol treated group suggests that misoprostol may exert an anti-inflammatory effect.     

Disodium cromoglycate in the treatment of ulcerative colitis and Crohn''s disease

A controlled clinical study on disodium cromoglycate (DSCG) at a dose of 800 mg per day versus placebo was carried out in 141 patients with ulcerative colitis and 25 patients with Crohn's disease. Those of the ulcerative colitis patients who had been on sulphasalazine treatment continued that treatment during the trial (101 patients). Forty patients were intolerant of sulphasalazine. No patient received steroids during the last month before the study. Patients with Crohn's disease had their possible sulphasalazine treatment stopped before the trial. No beneficial effect of DSCG as compared with placebo was found, as the DSCG and the placebo group showed the same number of relapses in patients with a clinically inactive ulcerative colitis at the start of the trial and the same number of patients improving, deteriorating, and maintaining steady state in patients with clinically active ulcerative colitis at the start of the trial. There was no difference between relapse rate in DSCG and placebo groups in patients with Crohn's disease. No correlation between the eosinophil count in rectal mucosa and the outcome of the attack of ulcerative colitis could be demonstrated.     

Controlled trial comparing olsalazine and sulphasalazine for the maintenance treatment of ulcerative colitis.

One hundred and sixty four patients with ulcerative colitis in remission were entered into a double blind, double dummy trial comparing olsalazine 500 mg bd and sulphasalazine 1 g bd. Clinical examination, sigmoidoscopy and rectal biopsy were performed at 0, three, and six months. Sixteen of 82 (19.5%) patients relapsed on olsalazine and 10/82 (12.2%) relapsed on sulphasalazine. The difference was not statistically significant (p = 0.1632). Adverse events were minor and were similar in both groups. No haematological or biochemical abnormalities were detected. Thus, olsalazine is as effective as sulphasalazine for preventing a relapse of ulcerative colitis.     

Optimum dosage of 5-aminosalicylic acid as rectal enemas in patients with active ulcerative colitis.

5-Aminosalicylic acid (5-ASA), the active moiety of sulphasalazine (SASP), was given as a rectal enema to patients with mild to moderate distal ulcerative colitis to determine the minimum effective dosage. A double blind study was carried out using enemas containing 1, 2, or 4 g or 5-ASA or placebo for a one month treatment period. One hundred and thirteen patients with ulcerative colitis attending our outpatient clinic volunteered to participate. Clinical, sigmoidoscopic, and histological assessments were carried out at the beginning of the study and after 15 and 30 days of treatment. All patients who received 5-ASA enemas showed significantly better results than those who received a placebo enema (p less than 0.001) but no difference was detected among the patients receiving differing concentrations of 5-ASA. This study suggests that 1 g 5-ASA (in a 100 ml enema) is a sufficient dosage for patients with a mild to moderate attack of ulcerative colitis.     

Prostaglandin synthetase activity in acute ulcerative colitis: effects of treatment with sulphasalazine, codeine phosphate and prednisolone.

Prostaglandin synthetase activity in rectal biopsy specimens from patients with ulcerative colitis has been shown to fall on treatment with sulphasalazine, local steroids, and codeine phosphate. In vitro studies have shown that sulphasalazine is an inhibitor of prostaglandin synthetase, although less potent than indomethacin, whereas prednisolone and codeine phosphate were inactive. It is suggested that the therapeutic action of sulphasalazine may be related in part to its action in inhibiting prostaglandin biosynthesis.     

Effect of sulphapyridine, 5-aminosalicylic acid, and placebo in patients with idiopathic proctitis: a study to determine the active therapeutic moiety of sulphasalazine.

Suppositories of sulphapyridine, 5-aminosalicylic acid, and placebo were used in 45 patients with idiopathic proctitis to determine the active part of sulphasalazine. Each patient used one of the suppositories twice daily for four weeks in a double-blind controlled trial. Complete clinical remission with normal rectal mucosa on sigmoidoscopy occurred in 60% of patients given 5-aminosalicylic acid, but in only 13% and 27% of those given sulphapyridine and placebo respectively. Twelve patients were included twice. In eight of these patients 5-aminosalicylic acid was given one time and sulphapyridine (two patients) or placebo (six patients) another time. Clinical remission occurred in each patient with 5-aminosalicylic acid, but in only one patient during other therapy. The results suggest that 5-aminosalicylic acid is the active therapeutic moiety of sulphasalazine.     

Regional cardiac prostaglandin release during myocardial ischemia in anesthetized dogs.

Cardiac prostaglandin release was studied in closed-chest dogs during acute coronary occlusion. Aortic and coronary sinus blood was obtained before, and at intervals after, balloon occlusion of the left anterior descending artery in seven dogs. Samples were assayed for prostaglandins F, E, and A by randioimmunoassay. All dogs demonstrated prostaglandin F release, Mean +/- SE postocclusion aortic levels were 0.26 +/- 0.01 ng/ml; coronary sinus levels were 0.67 +/- 0.01 ng/ml (P less than 0.001). In six dogs, prostaglandin E also was released. Mean postocclusion aortic levels were 0.24 +/- 0.01 ng/ml; coronary sinus, 0.44 +/- 0.01 ng/ml (P less than 0.001). There was no release of prostaglandin A. To examine the site of prostaglandin release, simultaneous samples from the aorta, the coronary sinus, and the great cardiac vein were obtained before and after left circumflex artery occlusion in six additional studies. The great cardiac vein drained effluent from nonischemic myocardium, whereas the coronary sinus drainage included blood from both ischemic and nonischemic zones. All six dogs demonstrated prostaglandin F release from the ischemic region. Mean postocclusion aortic prostaglandin F was 0.32 +/- 0.01 ng/ml. Coronary sinus prostaglandin F was 1.69 +/- 0.03 ng/ml (P less than 0.001), whereas the great cardiac vein level remained at 0.34 +/- 0.01 ng/ml (P greater than 0.05). Prostaglandin E was released from both ischemic and nonischemic regions. Mean aortic prostaglandin E was 0.21 +/- 0.01 ng/ml; great cardiac vein, 0.55 +/- 0.02 ng/ml (P less than 0.001); and coronary sinus, 1.07 +/- 0.04 ng/ml (P less than 0.001). These results have led us to conclude that the different local availability of prostaglandins E and F may influence the cardiac response to ischemia.