[Show abstract][Hide abstract] ABSTRACT: We evaluated the qualitative chemical composition and tested the antiulcer actions on cold/restraint stress ulcers, the healing effect on chronic acetic acid-induced gastric ulcers, and the in vivo and in vitro antioxidant capacity of Ocimum suave extract. Triterpenes, flavonoids, sugars, phenols, sterols, and multiple bonds were among the phytochemicals detected. The extract (250–500 mg/kg) dose-dependently inhibited the formation of gastric ulcers induced by cold/restraint stress (52.30%–83.10%). The prophylactic actions were associated with significant increases in gastric mucus production. There was significant histological healing of chronic ulcers following 14-day treatment with O. suave extract (250–500 mg/kg). We also evaluated the efficacy of O. suave extract in cold/restraint-induced oxidative stress in rat stomach tissue. O. suave (500 mg/kg) ameliorated the decreased levels of reduced glutathione from 0.85 (control group) to 2.08 nmol/g tissue. The levels of SOD and catalase were also improved in rats treated with O. suave extract. The extract had a high phenol content (899.87 mg phenol/g catechin equivalent), in vitro DPPH radical scavenging activity (89.29%), and FRAP (antioxidant capacity) (212.64 mg/g catechin equivalent). The cytoprotective and ulcer healing effects of the extract are attributed to enhanced mucus production and the antioxidant properties which may likely be associated with the high presence of flavonoids and polyphenols.
[Show abstract][Hide abstract] ABSTRACT: Enantia chlorantha Oliver (Annonaceae), widely used in Cameroonian folk medicine, has been previously shown to possess anti-ulcer, anti-trypanosomial and anti-Helicobacter properties. Other investigations have revealed the anti-malarial, antiviral, antibacterial and anti-hepatotoxic properties of this plant. In the present study the acute and sub-acute toxicity profiles of the aqueous stem-bark extract was evaluated. Swiss mice were administered single oral doses of 1000, 3000 and 5000 mg/kg and monitored for death and growth impairment for seven days (acute toxicity). In sub-acute toxicity, experimental rats, received daily doses of 250, 500, and 1000 mg/kg for 42 consecutive days and the toxic effects of the extract were assessed using biochemical and haematological parameters as well as the study of histological sections of vital body organs (heart, lungs, liver, kidneys, spleen, gonads and stomachs). No death or growth impairment was noticed in the mice in acute toxicity test. At 1000 mg/kg in the sub-acute toxicity study, the rats presented histopathological signs in the liver, lungs and kidneys, as well as significant (P< 0.05) increases in values of ALT, AST and platelet counts. The rest of the organs studied showed no signs of pathology. The extract of E. chlorantha, is not toxic in acute intake up to 5000 mg/kg, but can cause lung, hepatic and kidney disorders following medium-to-long term use at doses greater than 500 mg/kg.
[Show abstract][Hide abstract] ABSTRACT: The gastric cytoprotective actions of the extract of Ocimum suave wild (lamiaceae) have previously been demonstrated. We have investigated here the healing effect of the leaf methanol extract of Ocimum suave against chronic gastric ulcers induced in experimental rats. Chronic gastric ulcers were induced using acetic acid and the induced ulcers treated over a period of two weeks using daily oral doses (125 - 500 mg/kg) of the extract. Possible toxic effects of the extract given in the short term were also investigated. The extract reduced ulcer indices from 50.40 in the 4-day controls to 11.8, 5.8, and 3.6, respectively, for the rats receiving 125, 250 and 500 mg/kg of the extract. The highest dose of the extract (500 mg/kg) showed a highly significant (P < 0.001) reduction of ulceration with a corresponding healing rate of 81.25 per cent. Treatment with the plant extract was also associated with a significant increase in mucus production up to 57 per cent (P < 0.01) for the 500 mg/kg dose. A similar increase in mucus production was not observed with ranitidine although it generated a healing rate of 66 per cent. No apparent toxicity signs were observed through food and fluid intakes, vital organ weights, animal behaviour, stool texture, red and white blood cell counts and histopathological evaluation. The results of the present study show that in addition to the previously demonstrated cytoprotective antiulcer actions of the leaf methanol extract of O. suave, the extract also possesses potent healing effects against chronic gastric ulcers. Enhanced mucus production appears to play a significant role in the mode of action of the extract
[Show abstract][Hide abstract] ABSTRACT: Decoctions prepared from Enantia chlorantha are used in the traditional treatment of some forms of ulcers. We have tested the anti-ulcer actions of a novel protoberberine-type alkaloid (7,8,-dihydro-8-hydroxypalmatine (1)) obtained from the bark of E. chlorantha using the HCl/ethanol, absolute ethanol and pylorus ligation techniques. The healing effect on chronic acetic acid-induced gastric ulcer was also tested. 1 (50 and 100 mg/kg) dose-dependently inhibited the formation of gastric ulcers induced by HCl/ethanol (35-52% inhibition), absolute ethanol (46-53% inhibition) and pylorus ligation (38-62% inhibition). The prophylactic actions were associated with significant increases in gastric mucus production compared with the controls. The significant inhibition of pylorus-ligated ulcers occurred at gastric acid concentrations (83 mEq/l) previously known to induce severe gastric ulceration in rats. The ulcer-healing test showed significant macromorphological and histological acceleration of healing following 10-day treatment with 1 (40 - 80 mg/kg). The results show that 1 has no anti-secretory effects. The prophylactic anti-ulcer effects are associated with enhanced mucus production, which is an important factor in the mechanism of the local healing process of chronic gastric ulcers.