Abstract:
Bergapten (5-methoxysporalen) is a furanocoumarin extracted from several species of citrus and bergamot oil.
Bergamot essential oil is used traditionally in the management of inflammatory conditions. Previous studies on
bergapten have explored mainly its in vitro anti-inflammatory activities which include suppression of the
expression and release of pro-inflammatory cytokines such as TNF-α and interleukins as well as prostaglandins.
Bergapten enhances the clearance of neutrophils and macrophages from the site of inflammation and reduces
oxidative stress by inhibition of reactive oxygen species (ROS). Bergapten was assessed for its anti-inflammatory
properties in acetic acid-induced colitis. Animals were obtained and randomly placed in six (6) groups (n ¼ 5)
after acclimatization. Colitis was induced by rectal administration using 4% v/v acetic acid in Sprague Dawley rats
after pre-treatment for 5 days. Bergapten was administered at doses of 3, 10, and 30 mg kg 1 p.o. while the
control group received saline 5 mL kg 1 p.o. and the standard drug employed was sulphasalazine at a dose of 500
mg kg 1. Assessments made for colon-weight-to-length ratio, colonic injury, and mucosal mast cell degranulation.
There were reduced colon-weight-to-length ratios in animals treated with bergapten which was significant (p <
0.5) for doses 10 and 30 mg kg 1 compared to the disease control group Both macroscopic and microscopic
damage were reduced as well, with a lesser percentage of degranulated mast cells. Macroscopic damage was
reduced for bergapten at doses 10 and 30 mg kg 1 significantly at p < 0.5 and p < 0.001, respectively. Similarly,
microscopic damage was reduced at p < 0.01 and p < 0.001 respectively for bergapten 10 and 30 mg kg 1. The
reduction of degranulation by bergapten was significant at p < 0.001. There was generally reduced damage at
inflammatory sites as well as decreased infiltration of inflammatory cells. Overall, bergapten reduces inflam-
mation in acetic acid-induced colitis.
