Acute toxicity evaluation of Holothuria scabra Jaeger extract and its effects on induced gastric ulcer in rats

Abstract

Holothuria scabra is one of edible marine animals which is widely consumed by Chinese and local Sabahan people, who believe in the medicinal properties offered by the species. This work was focusing on H. scabra in the attempt of finding new therapeutic properties, because of its large availability in the coastal area of Sabah and ability to be widely bred in hatcheries for restocking purpose. The study comprises of two types of study: anti-gastric ulcer and acute toxicity test, to investigate the existence of anti-gastric ulcer property in the species and its safety for human consumption. In the anti-gastric ulcer study, 150 mg/ml H. scabra water extract was administered into rats that had been induced with gastric ulcer by using acetic acid. Histology of the stomach was examined and the gastric mucous was estimated by using spectrophotometer. The toxicity test was conducted by giving H. scabra water extract with the doses of 5, 50, 300 and 2000 mg/kg into four groups of rats, whereas the control group received distilled water. Survival and toxicity signs were carefully observed for 14 days, in addition to performing the blood analyses and histopathological examination of liver and kidney tissues. For the anti-gastric ulcer study, the stomach tissues from both groups of treated and untreated were recovering, with no significant difference in terms of structural changes and inflammatory cell infiltrates. The treated rats did not produce significant higher amount of gastric mucous as compared to the non-treated rats, except on the day 12 of the experiment. In the toxicity test, no mortality and toxicity signs were observed throughout the observation period. Gross examination on liver and kidneys showed no changes in appearance, size, and colour of the organs when compared to the control group. Statistical analysis of the Kruskal-Wallis H test produced no significant difference in body weight between the control and all treated groups after the treatment, x2(4, N = 23) = 5.754, p = 0.218. The haematological and biochemical blood parameters of the treated group of rats also showed no statistical difference as compared to the control. However, histopathological examination revealed presence of necrotic tissues and cellular damages in the liver and kidneys of all treated rats at all doses of extract. The study suggests that the effects of H. scabra water extract on the healing of induced gastric ulcer in rats were not conclusive. However, since blood analyses results and histopathological findings of the acute toxicity study were contradict, sub-acute toxicity is suggested to be conducted in future to further confirm the toxicity level of the extract.