Allopurinol and 5-aminosalicylic acid influence thiopurine-induced hepatotoxicity in vitro

Mesalazine (5-aminosalicylic acid) induced chronic hepatitis.

BACKGROUND Treatment of ulcerative colitis or Crohn's disease with sulphasalazine causes several adverse effects, including hepatitis. Sulphasalazine is cleaved by colonic bacteria into 5-aminosalicylic acid and sulphapyridine. Received wisdom was that 5-aminosalicylic acid was topically active, whereas sulphapyridine was absorbed and caused immunoallergic side effects. Mesalazine, a slow relea...

Electrochemical Synthesis of 5-Aminosalicylic Acid from 5- Nitrosalicylic Acid in Alkaline Media

5-Aminosalicylic acid (5-ASA) is currently prepared by electrochemical reduction of 5-nitrosalicylic acid (5-NSA) in acidic media. In this work, electrolytic reduction of 5-NSA in alkaline media is presented. Reactionconditions and parameters such as anode and cathode electrodes, electrolyte type, reaction time, temperature,current, and the pH for isolation of product are investigated. The yiel...

Xanthine oxidase inhibition by allopurinol increases in vitro pyrazinamide-induced hepatotoxicity in HepG2 cells.

Despite the important role of pyrazinamide in tuberculosis treatment, little is known about the mechanism of pyrazinamide-induced hepatotoxicity. We inhibited xanthine oxidase in HepG2 cells by using a nontoxic concentration of allopurinol, a well-known xanthine-oxidase inhibitor. This increased in vitro pyrazinamide toxicity in HepG2 cells, which suggests that the hydroxy metabolites of pyrazi...

Nephrotoxic lesions from 5-aminosalicylic Acid.

5-Aminosalicylic acid given to rats as a single intravenous injection led to necrosis of the proximal convoluted tubules and of the renal papilla. These two lesions developed at the same time and the cortical lesions did not appear to be a consequence of the renal papillary necrosis. Since the compound possesses the molecular structure both of a phenacetin derivative and of a salicylate these o...

aminosalicylic acid to 5-aminosalicylic acid in topical treatment of ulcerative colitis. Digestion