| dc.description.abstract | Betulinic acid (BA) is a lupane-type triterpene that has been identified and isolated
from different plant species used in ethnomedicine worldwide. It is known to
possess anti-ulcer, anti-tumor and anti-microbial properties. However, the
mechanism underlying the anti-ulcer property of BA has not been well
investigated. The effect of BA on indomethacin-induced peptic ulcer, gastric
mucus secretion (GMS), gastric mucus cell count (GMCC), basal and histamine induced
gastric acid secretion (GAS), and malondialdehyde (MDA) concentration
level were studied as means of elucidating the mechanism.
Thirty-two rats divided into four groups of eight rats each were used for each
study. Group I (Control) was pretreated orally with dimethyl sulfoxide (DMSO) in
normal saline for seven days. Groups II, III and IV were pretreated orally with BA
(0.5 mg/kg, 1.5 mg/kg, and 3.0 mg/kg) dissolved in DMSO respectively for seven
days. Gastric ulceration was induced using indomethacin and scored by ulcer
scoring technique. Measurement of GMS was performed using spectrophotometric
method, while GMCC was done by using calibrated microscopy. Continuous
perfusion technique was used to assess GAS and its acidity determined by titration.
Histological study of the stomach mucosa was also carried out. MDA levels were
determined by measuring thiobarbituric acid reactive substances produced. Data
were expressed as Mean ± SEM. Student’s t-test and one way ANOVA were used
to determine levels of significance at p<0.05.
There was a dose - dependent reduction in ulcer scores in the BA treated animals.
This reduction was significant at doses of 1.5mg/kg (0.75 0.10) and 3.0mg/kg
(0.25 0.09) compared to the control (7.0 0.27). GMS (mg/g tissue x 10-2)
significantly increased in the 1.5 mg/kg (4.9 ± 0.22) and 3.0 mg/kg (5.2 ± 0.09)
pretreated groups compared to the control (4.4 ± 0.20) group. There was also a
dose-dependent significant increase in the GMCC/mm2 of rats treated with 0.5
mg/kg (44.4 ± 0.84); 1.5 mg/kg (45.9 ± 0.79); 3.0 mg/kg (54.1± 0.71)] compared
with the control group (41.4 ± 0.71). The histamine-induced GAS was significantly
higher than the basal GAS. However, there was a significant decrease in GAS of
BA treated groups compared with the control. Histological study showed
significant hyperplasia of mucus cells in BA treated groups compared to the
control group. There was a significant decrease in MDA (μmol/L x 10-6) levels in
groups II, III and IV (1.86± 0.076, 1.83 ± 0.069 and 1.10 ± 0.056) compared to the
control (2.60 ± 0.110) group.
The results of the study suggest that betulinic acid produces anti-ulcer effect by
increasing gastric mucus secretion, gastric mucus cell count and decreasing
malonialdehyde concentration. It decreases gastric acid secretion via the blocking
of H2-receptors. | en_US |
