European Journal of Molecular & Clinical Medicine

Background:Ulcerative colitis (UC) is a chronic inflammatory disease of large intestine.
Overproduction of free radicals, lowered antioxidant capacity, inflammation and
abnormal apoptosis are involved in its pathogenesis. Propranolol and carvedilol, β-
blockers with antioxidant and anti-inflammatory effects which may have a protective role
in UC.
The study aimed to evaluate and compare the effects of propranolol and carvedilol on UC
development and to distinguish which of them have greater beneficial effect on
experimentally-induced UC in male albino rats.
Methods: Fifty male albino rats were randomly allocated to five groups with each group
comprising eleven rats except control group composed of six rats. Group (1): control
group, Group (2): ulcerative colitis group, Group (3): propranolol-pretreated (30
mg/kg/d), Group (4): carvedilol-pretreated (30 mg/kg/d) and Group (5): mesalazinepretreated
(300 mg/kg/d). Treated groups received drugs by oral gavage for seven days
before and three days after induction of colitis. UC was induced in groups 2 to 5 by
intrarectal administration of 1ml of 4% Acetic Acid (AA), while group (1)received 1 ml of
normal saline solution administered intrarectally instead. To estimate the severity of AAinduced
UC and the effect of propranolol and carvedilol, the following parameters were
measured: colon weight/length (W/L) ratio, colon weight/body weight (CW/BW) ratio,
colonic malondialdehyde (MDA) and colonic markers of inflammation [tumor necrosis
factor (TNF-α) and nuclear factor kappa B (NF-κB)] and macroscopic and microscopic
scorings.
Results:In UC group, colon W/L ratio, CW/BW ratio, macroscopic and microscopic
scorings and colonic levels of MDA, TNF-α and NF-κBwere significantly increased.
Pretreatment with propranolol, carvedilol and mesalazine significantly reduced these
parameters when compared to UC group. However, colon W/L ratio, CW/BW ratio,
macroscopic scoring of mucosal damage and colonic MDA, TNF-α and, NF-κB levels in
carvedilol-pretreated group were significantly lower than propranolol-pretreated group.
Conclusion:Both propranolol and carvedilol had a coloprotective effect againstAAinduced
UC depending on their ability to decreases inflammation and oxidative stress
state in rat colon; butcarvedilol had better effects than propranolol. Thus, carvedilol can
be considered the β-blocker of benefit in patients with UC who have other co-existing
diseases indicatingthe use of β-blockers.