Bromelain oral administration

Another subclass of proteases attacks internal peptide bonds and liberates large peptide fragments. Bromelain, a plant protease derived from the stem of the pineapple plant, can even produce detectable serum proteolysis after oral administration (180). Oral therapy with bromelain significandy reduces bruising that stems from obstetrical manipulations (181). Bromelain—pancreatin combinations have been more effective in digestive insufficiency compared to either pancreatin or placebo (182,183). Bromelain may also enhance the activity of antibiotics, especially tetracycline, when administered concurrendy (184). 

Oral administration of bromelain to rats resulted in an increase in proteolytic activity in blood [82]. Seifert et al, [S3] administered radioactive bromelain via the duodenum to rata. They proved that 40% of the radioactively tagged bromelain was absorbed in its high molecular weight form in blood and lymph. The enzyme was identified using anti bromelain antiserum raised in rabbits. They claimed that a proteolytic enzyme of about 28,000 daltons passed into the blood and then exerts its physiological action [84]. 

R D, Smyth, R. M. Brennan, and G, J, Martin. Systemic biochemical charges following die oral administration of a proteolytic enzyme, bromelain. Arch. Ini. Phormacodyn. Ther. 136-230 (1962). 

R. R, White, F. E. Crawley, M. Vdiini, and L A. Rovatti. Bioavailability of 1251 bromelain after oral administration to rats. Btopharm. Drug Dispos. 9 397 (1988). 

One of the most important questions to be answered is whether it is possible to absorb intact bromelain in the gastrointestinal tract following oral administration. Smyth et al. reported the absorption of dye-labeled bromelain [79] and I131-labeled bromelain [80]. Izaka et al. [81] used I125-labeled bromelain to... 

White et al. [85] also administered I125-labeled bromelain orally to rats. At various times blood was drawn and the total radioactivity, the trichloroacetic acid precipitable I125 compounds, and the molecular weight profiles of the labeled proteins were determined. They found a maximum absorption in the blood, corresponding to 270 ng/mL bromelain, one hour after bromelain administration. Approximately 40% of the radioactivity in plasma could be precipitated by 10% trichloroacetic acid. Electrophoretic analysis showed one major peak of radioactivity in plasma, with a molecular weight of 26,000-30,000 daltons. This maximum peak contained 0.003% of the administered dose of bromelain per mL plasma. 

J. M. Miller and A. W. Opher. The increased proteolytic activity of human blood serum after oral administration of bromelain. Exp. Med. Surg. 22 277 (1964). 

F. Pirotta and C. De Giuli-Morghen. Bromelain, a deeper pharmacological study. I. Anti-inflammatory and serum fibrinolytic activity after oral administration in the rat. Drugs Exp. Clin. Res. 4 1 (1978). 

Acute oral doses of up to 10 g/kg in mice failed to produce lethality, and chronic oral administration of bromelain (500mg/kg) in rats produced no adverse effects. ... 

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