Mohammed Musa Suleiman

A controlled study to investigate anti-diarrhoeal effect of the stem-bark fractions of Terminalia avicennioides in laboratory animal models

Abstract Due to the shortcomings associated with modern synthetic antidiarrhoeal drugs, it is important to find newer, safer and cheaper antidiarrhoeal agents from natural sources. The study was conducted to evaluate the anti-diarrhoeal activity of the fractions of the stem-bark of Terminalia avicennioides in laboratory animal models. The effect of different concentrations (1.0 × 10−3, 2.0 × 10−3, 4.0 × 10−3 and 8.0 × 10−3 mg/mL) of the aqueous methanol (AMF), ethyl acetate (EAF) and hexane (HXF) fractions of T. avicennioides were tested against spontaneous and acetylcholine-induced contractions of rabbit jejunum as well as on histamine-induced contraction of guinea pig ileum. Similarly, the effects of the AMF on gastro-intestinal transit time, castor oil-induced diarrhoea and castor oil-induced enteropooling were evaluated. The AMF, EAF and HXF at concentrations of 1.0 × 10−3, 2.0 × 10−3, 4.0 × 10−3 and 8.0 × 10−3 mg/mL attenuated the contractile effects of both the spontaneous and acetylcholine-induced contractions of rabbit jejunum and that of histamine-induced contraction of guinea pig ileum in a concentration-dependent manner. The AMF at doses of 200, 300 and 500 mg/kg produced significant (p < 0.05) reductions in gastrointestinal transit time of charcoal and incidence of castor oil-induced diarrhoea in mice relative to the untreated control. Similarly, at doses of 300 and 500 mg/kg, AMF significantly (p < 0.05) reduced the weight and volume of intestinal fluid in the treated mice when compared to the untreated animals. The results of this study showed that the stem-bark of T. avicennioides possesses spasmolytic effect and could be a potential antidiarrhoeal agent. However, detailed pharmacological trials are required to justify the clinical use of the plant for treating diarrhoea.

In vivo ameliorative effects of methanol leaf extract of Lawsonia inermis Linn on experimental Trypanosoma congolense infection in Wistar rats

Abstract The aim of this study was to investigate the ameliorative effect of Lawsonia inermis Linn used traditionally against trypanosomosis. Twenty-five adult Wistar rats of both sex were individually infected intraperitoneally (IP) with 106 Trypanosoma congolense per ml of blood. Following establishment of infection, the rats were randomly divided into five groups of 5 rats each. Rats in groups I, II, and III were treated with 125, 250 and 500 mg/kg of the extract, respectively, while rats in groups IV and V were treated with 3.5 mg/kg and 2 ml/kg of diminazene aceturate (DM) once and physiological buffered saline, respectively. All treatments except DM were given orally for 7 days IP. The antitrypanosomal effect of the plant was assessed by observing the level of parasitaemia daily, packed cell volume (PCV) weekly, erythrocyte osmotic fragility (EOF) and malondialdehyde (MDA) concentration on day 21. Phytochemical screening of the extract revealed the presence of alkaloids, carbohydrates, triterpenes, steroids, cardiac glycosides, saponins, tannins and flavonoids. The extract significantly (P < 0.05) reduced levels of parasitaemia at 250 mg/kg. PCV was higher (P > 0.05) in extract treated groups but significantly higher (P < 0.05) in group II at week 2 when compared to group V. Rats in group II had significantly lower values of EOF and MDA when compared with groups IV and V. Thus, the leaf of L. inermis has in addition to an antitrypanosomal effect against T. congolense in rats, an attenuating effect on the trypanosomosis pathology probably mediated via protection of the erythrocyte membrane against trypanosome-induced oxidative damage to the erythrocytes.