Histopathology induced by a medicinal plant indigenous to South Africa that has shown in vitro anti-microbial activity against drug resistant strains of Mycobacterium tuberculosis

Tuberculosis (TB) still remains a health problem globally with over a million new infections and a mortality rate of 1.5 million individuals annually (Hawn et al., 2014). The emerging multi-drug resistant (MDR) strains that accompany human immune deficiency virus (HIV) infection in high-incidence populations contribute significantly to the health burden of TB (Areeshi et al., 2014). The standard treatment that is advocated by the World Health Organization (WHO) for active tuberculosis includes long-term therapy that incorporates the use of isoniazid, rifampicin, pyrazinimide and ethambutol as front line drugs (WHO, 2013). Drug resistance against established treatment options for TB makes research into new forms of therapy an imperative in health care (Ntulela et al., 2009). South Africa is currently witnessing a high number of cases of drug-resistant TB. In some parts of the country, one in ten cases of TB is resistant to treatment. It is therefore essential to have new anti-tuberculosis agents, which can be readily and simply produced from some local source (Warner et al., 2014). A logical starting point for this research of new agents would be the herbal medicines which have been used for centuries in rural areas by local healers. Western developed countries have harvested ethno botanical knowledge and have produced drug therapies for conventional medicines for other ailments. The activity of extracts of the active plants and their properties still require study in animal models in order to assess their future as new anti-tuberculosis agents (Lall and Meyer, 1999). This study focuses on qualitative and quantitative experimental findings after the administration of a medicinal plant extract to animals. This will include daily observation of animals, recording of feed consumption, recording of animal weights, macroscopic examination of animals at necropsy, tissue harvesting, histological procedures and microscopy

EVALUATION OF ANTIDIARRHEAL ACTIVITY OF ETHANOLIC LEAF EXTRACT OF ERIOBOTRYA JAPONICA LINDL

Objective: The study was carried out to investigate the antidiarrheal activity of ethanolic leaf extract of Eriobotrya japonica (EEJ) using various models of experimental diarrhea.Methods: Antidiarrheal property of EEJ at 100, 200, and 400 mg/kg/bwt was evaluated using castor oil-induced diarrhea, castor oil-induced enteropooling, and gastrointestinal propulsive models of experimental diarrhea in Sprague Dawley rats of both sexes, weighing 200–250 g. Cytotoxicity test of EEJ was performed using brine shrimp bioassay.Results: Toxicity assay of EEJ showed a lethal concentration value of 1225 μg/ml suggesting non-toxicity. EEJ significantly (p<0.05) and dose-dependently (100, 200 and 400 mg/kg/bwt) inhibited castor oil-induced diarrhea by 38.1%, 76.19%, and 100%, respectively, and enteropooling by 28%, 56%, and 88%, respectively, compared with control. Pre-treatment with yohimbine, α2-adrenoceptor blocker significantly reversed the protective effect of EEJ (400 mg/kg) against castor oil-induced diarrhea and against castor oil-induced enteropooling, suggesting the involvement of α2-adrenoceptors in antidiarrheal property of EEJ. Furthermore, EEJ significantly (p<0.05) and dosedependently (100, 200, and 400 mg/Kg/bwt) inhibited gastrointestinal motility by 28%, 62%, and 83.92%, respectively.Conclusion: The study has demonstrated the antidiarrheal potential of ethanolic leaf extract of EEJ, which may be attributable to its dual antisecretory and antimotility activities probably through activation of the sympathetic α2-adrenergic pathway

EVALUATION OF ANTIDIABETIC AND ANTIOXIDANT EFFECTS OF ETHANOLIC LEAF EXTRACT OF ERYTHRINA ABBYSINICA LAM, EX DC

  Objective: This study was conducted to scientifically evaluate the antidiabetic and antioxidant effects of ethanolic leaf extract of Erythrina abbysinica (EEA).Methods: Acute and sub-chronic effects of EEA at 100, 200, and 400 mg/kg/bwt and glibenclamide (GL) at 5 mg/kg/bwt. were evaluated in both normal and streptozotocin (STZ)-induced diabetic male Wistar rats (250–300 g). The acute studies were performed using oral glucose tolerance test (OGTT). In sub-chronic studies, animals were orally administered with EEA and GL daily for 6 w. Brine shrimp assay was used to determine the toxicity of EEA. 1, 1-diphenyl-2-picrylhydrazyl, ferric reducing capacity of plasma, and thiobarbituric acid reactive substances assays were used to determine antioxidant properties of EEA.Results: Following OGTT, EEA significantly (p<0.05) and dose-dependently (100, 200, and 400 mg/kg/bwt) decreased blood glucose levels in both normal and STZ-induced diabetic rats when compared with positive and negative control counterparts at all-time points, whereas GL significantly (p<0.05) decreased blood glucose only in normal rats but not in diabetic rats. Daily, oral administration of EEA for 6 w significantly (p<0.05) and dose-dependently (100, 200, and 400 mg/kg/bwt) decreased blood glucose levels in STZ-induced diabetic rats when compared with the diabetic control group. EEA revealed weak toxicity with a lethal concentration50 value of 997 μg/ml). Furthermore, EEA showed significant free radical scavenging, total antioxidant, and anti-lipid peroxidative capacities.Conclusion: The study has shed more light on the scientific basis for the use of E. abbysinica in management of diabetes in some communities of Eastern Cape of South Africa

INVESTIGATION OF ANTI-INFLAMMATORY AND ANTINOCICEPTIVE EFFECTS OF AQUEOUS EXTRACTS OF ARTEMISIA AFRA IN WISTAR RATS

Objective: The objective of the study was to evaluate the anti-inflammatory and antinociceptive effects of Artemisia afra.Methods: Animals were randomly divided into five groups of six animals each and administered with normal saline (2 ml/kg), indomethacin (10 mg/ kg), and A. afra at doses of 100, 200, and 400 mg/kg, respectively. For the anti-inflammatory activity, carrageenan-induced paw edema was used while the hot plate and acetic acid induced-writhing tests were used to assess the antinociceptive activity.Results: Pretreatment with A. afra at a dose of 100 mg/kg did not show any significant biological effects (p>0.05) for any of the three tests, when compared against saline-treated control group. At a dose of 200 mg/kg, A. afra demonstrated significant effects (p<0.01), during the 5th h reducing carrageenan-induced paw edema by 12%. The highest dose (400 mg/kg) of A. afra demonstrated more potent effects by decreasing the carrageenan-induced paw swelling (p<0.001–0.05) during the 3rd, 4th, and 5th h, by up to 38% when compared against saline-treated control group. Both the 200 and 400 mg/kg, A. afra doses achieved a significant increase (p<0.05) in reaction time in the hot plate test. In the acetic acid-induced writhing test, pretreatment with A. afra (400 mg/kg) significantly reduced pain by 39% (p<0.01) by comparison with the saline control.Conclusion: Experimental data demonstrated that aqueous extract of A. afra possesses anti-inflammatory and antinociceptive properties in experimental acute inflammation and pain. These findings support the usage of A. afra in managing inflammation and pain in traditional practice