Gastro-protective effects and anti-Helicobacter pylori activities of the aqueous and methanol extracts of the stem-back of Nauclea pobeguinii (Rubiaceae)

Abstract

Nauclea pobeguinii (N. pobeguinii) is a plant used in African medicine to treat many gastroduodenal diseases. In this study, we determined the gastro-protective mechanisms and anti-Helicobacter pylori (H. pylori) properties of N. pobeguinii extracts. Wound healing activity (acetic acid test), anti-secretory properties (pyloric ligation, pyloric ligation/acetylcholine and pyloric ligation/histamine tests) and cytoprotective effects (ethanol test) were assessed in female rat, the anti-Helicobacter pylori (agar well diffusion method) was also evaluated. At doses of 100, 200 and 400 mg/kg, the extracts reduce (p < 0.001) the various ulceration parameters. In the acetic acid test, the extracts (200 mg/kg) reduced ulcerated areas by 99.23% (aqueous) and by 98.47% (methanol), levels of monocytes, lymphocytes, nitrogen, malondialdehyde and increased (p < 0.001) superoxide dismutase and catalase activities. Histological analysis showed repair of the mucosal epithelium at all doses of both extracts. Aqueous and methanol extracts inhibited ulceration indices by 99.68 and 99.33% (pyloric ligation), 83.81% and 61.07% (pyloric ligation/acetylcholine), 97.49% and 98.50% (pylorus ligation/histamine); they increased (p < 0.001) the mucus mass and uterine mass. In vitro, the different H. pylori isolates were sensitive to both extracts; the aqueous extract showed strong anti-urease activity, a large diameter of the inhibitory zone and a better minimum inhibitory concentration. Aqueous and methanolic extracts of N. pobeguinii healed ulcers through their estrogen-modulating anti-inflammatory, antioxidant, anti-secretory and cytoprotective properties. The aqueous extract of N. pobeguinii could be a good solution for the treatment of this infection.