ABSTRACT
Background: Vernonia amygdalina is a common medicinal plant that is widely used by local communities and traditional herbalists in central Uganda in management of various conditions including hypertension that occurs as a result of changes in heart contractility. However, there is limited scientific information of V. amygdalina effects on the force and rate of contractility of the heart. The study evaluated the inotropic and chronotropic effect of methanol, aqueous, ether and total crude leaf extracts of V. amygdalina on isolated perfused rabbit heart.Methods: An experimental laboratory based study determined the effects of V. amygdalina extracts on the rate and force of contraction isolated perfused rabbit using the Langendorff抯 heart perfusion experiment and methods. The heart rate (beats/minute) was counted per minute. The force of contraction of the heart was determined measuring the height of each peak on the kymogram.Results: The findings showed that the force and rate of heart contractility reduced with increasing doses of methanol, aqueous ether and total crude leaf extracts at doses of 0.5, 8.0, 62.0 and 250.0 mg/ml. The force and rate of heart contractility at a dose of 250.0 mg/ml for all the extracts were comparable to that of acetylcholine drug to almost causing cardiac arrest.Conclusions: The leaf extracts of V. amygdalina contain compounds that reduced the force and rate of contraction of an isolated rabbit heart.
ABSTRACT
Malaria is a major cause of death among pregnant women and children under the age of five in Uganda. It is the leading cause of anemia among pregnant women and low birth weight in infants [1]. Majority of the rural population rely on herbs for treatment of various diseases. The leaf extracts of various plants including Bothlioclines longipes, Vernonia amygdalina, Rhus natalensis and Maesa lanceolata are used to treat various diseases including malaria in Uganda. The local communities prefer herbal preparations from the leaves of the plants. Extracts from the leaves of the plants were proven efficacious against P. falciparum in earlier studies in vitro. This study was carried out to investigate the effect of Diethyl ether and methanol extracts on the contractility of an isolated rabbit uterus and also to quantitatively analyze for iron and zinc in the leaves of these plants. The diethyl ether extracts of V. amygdalina, M. lanceolata and R. natalensis at a concentration of 0.4 mg/ml and 0.8 mg/ml exhibited contractility amplitudes of 26.0 mm, 21.5 mm and 27.5 mm and 22.5±1.10 mm, 15.0±1.78 mm and 24.5 ±0.99 mm respectively. The methanol extracts were 25.5±0.70 mm, 23±1.34 mm, 22±1.01 mm and 37.8±1.26 mm, 16.7±2.01 mm, 24.3±0.06 mm respectively, while oxytocin showed 22.8±0.57 mm and 31.0±0.36 mm respectively. The plant leaves were found to have high levels of iron ranging from 2516.587±17.983 (mg/100 g) in B. longipes to 583.317±9.505 (mg/100 g) in V. amygdalina. Rhus natalensis and V. amygdalina had low levels of Zinc. Anti-nutritive phytocompounds such as saponins and Tannins were also detected in some of the test extracts. The study concludes that plants used by pregnant women may have either a positive or negative effect on expectant mothers. There is need to formulate evidence based effective medicines for their safe use in the management of malaria.
ABSTRACT
Background: Decaying stem juice of Musa acuminata × balbisiana is commonly used by local communities and traditional herbalist in Central Uganda in the management of cardiovascular conditions like hypertension. Aims: The study investigated the ionotropic and chronotropic effect of fresh and decaying stem juice of Musa acuminata × balbisiana on the isolated perfused rabbit heart. Materials and Methods: Methods. Study Design: An experimental study. Place and Duration of Study: Study was done at the Dept of Pharmacology & Therapeutics Pharmacology Lab between December 2012 to March 2013. Experimental Procedure: An experimental study determined the effects of fresh and decayed stem juices of Musa acuminate X balbisiana on the rate and force of contraction of an isolated rabbit heart using Langendorff’s heart perfusion experiment and methods. The heart rate (beats/minute) was determined. The force of contraction of the heart was determined by measuring the height of each peak on the kymogram. Results: The force and rate of contractility of an isolated perfused rabbit decreased with increasing doses of the stem juice from 0.156 mg/mL to 100mg/mL for both the fresh and decayed stem juice of M. acuminata. The decrease could be associated with the high [K+] ions that decrease the membrane potential or cause hyperpolarization the myocardial cell membranes leading to reduced force and rate of heart contractility. The effect of the fresh stem juice was short lived and at very high concentrations, it caused a cardiac arrest while the effect of the decayed stem juice was prolonged. Conclusion: Fresh and decayed stem juice of Musa acuminata × balbisiana have compounds that cause a negative ionotropic and chronotropic effect on an isolated perfused rabbit heart.
ABSTRACT
Background: Medicinal herbs have long been used in the treatment of malaria in the endemic tropical and subtropical regions of the world, especially in sub-Saharan Africa where malaria has remained as a top killer disease to children under five years and expectant mothers. Among the herbs commonly used in Uganda to treat malaria is Zanthoxylum chalybeum (ZC) root-bark and to a lesser extent its leaves. However, the continued use of the root-bark has led to plant extinction due to the destructive method of harvesting the herb as opposed to the leaves. Aim: The study investigated the antiplasmodial activity of the crude ether and methanol leaf extracts of ZC with chloroquine diphosphate as a positive control. Materials and Methods: The in vitro Micro-Test (MARK III) kit was used to determine the antiplasmodial activity of Z. chalybeum Engl. ether and methanol extracts. The effective concentration that caused a 50% P. falciparum schizonts suppression (EC50) values were determined. The antiplasmodial activities of the ether and methanol extracts were expressed as 50% effective concentration (EC50) that was determined from doseresponse curve by non-linear regression analysis (curve-fit) using GraphPad Prism (version 6) software at 95% confidence intervals. Results: The results showed that ether extract of ZC had EC50 value of 13.39 (95% CI: 10.82 – 16.59) μg/ml and methanol extract had EC50 value of 8.10 (95% CI: 5.89 – 11.12) μg/ml. The chloroquine diphosphate, standard had EC50 value of 25.33 (95% CI: 17.07 – 37.60) μg/ml. Conclusion: The ether and methanol extracts of Z. chalybeum Engl. contains compounds that caused Plasmodium falciparum schizonts suppression at a lower concentration, hence the continued use of the herb by the traditional herbalist and local communities in Uganda, in the treatment of malaria.
ABSTRACT
Alcohol consumption is common problem in Uganda. Among the types of alcohols consumed include beers, spirits, liqueurs, wines and traditional brew. These alcohols are easily accessible and consumed by many people including the HIV infected patients who are on the d4T/3TC/NVP regimen. The aim of this study was to determine the effect of chronic alcohol intake on the red blood cell count (RBC) and the RBC indices in the HIV-infected patients on d4T/3TC/NVP regimen. It was a case control study that used a repeated measures design model where serial measurements of the red blood cell count (RBC) and RBC indices were determined at 3 month interval for 9 months. A total of 41 HIV infected patients were recruited and grouped into two arms; the control group had 21 patients and the chronic alcohol group had 20 patients. The RBC and RBC indices of the whole blood were determined using automated hematological Coulter CBC-5 Hematology Analyzer system using standard procedures. The data was sorted into alcohol-use self reporting by WHO AUDIT tool and alcohol-use biomarkers groups. It was analysed using the SAS 2003 version 9.1 statistical package with the repeated measures fixed model. The means were compared using the student t-test. The mean MCV and MCH values in the chronic alcohol use group were higher than in the control group and there was a significant difference between the 2 groups (p<0.05) for both the WHO AUDIT tool group and chronic alcohol use biomarkers group. The mean RBC count, Hct, HGB and MCHC values in both the control and chronic alcohol use groups were within the normal reference ranges for both groups though the trend was lower in alcohol group. Chronic alcohol use affects the RBC and RBC indices in the HIV infected patients on d4T/3TC/NVP treatment regimen.
ABSTRACT
Chronic alcohol consumption is a common problem among the HIV-infected patients on HAART. The study determined the effect of chronic alcohol use on steady state plasma drug concentrations of stavudine (d4T), lamivudine (3TC) and nevirapine (NVP) in HIV-infected patients during the 9 months follow up period. It also determined whether there were some patients with undetectable plasma drug concentrations in their plasma during the follow up. A case control using repeated measures design with serial measurements model, where plasma drug concentrations were measured at 3 month intervals was used. Chronic alcohol-use using WHO AUDIT tool was used to screen patients. A total of 41 patients (21 alcohol group and 20 control group) were followed up for 9 months with blood sampling done at 3 month intervals. The Shimadzu Class-VPTM HPLC Chromatography data system version 6.1 equipment with UV detector was used to measure the plasma drug concentrations. Data was analyzed using SAS 2003 version 9.1 statistical package with repeated measures fixed the model and means were compared using the student t-test. The mean steady state plasma concentration of both d4T and 3TC in chronic alcohol use group were lower than in the control group all throughout the 9 months period of follow-up. The mean steady state plasma drug concentrations of NVP were higher in the alcohol group at 0 and 3 months and lower in the 6 and 9 months as compared to the control group. The mean total plasma NVP concentration was higher in the chronic alcohol group as compared to the control group and the difference was statistically significant (p≤0.05). However some patients had undetectable plasma drug concentrations despite of having ≥ 95 % adherence rate. Chronic alcohol use by the HIV-infected patients lowers the steady state plasma drug concentrations of d4T, 3TC and NVP in patients.