Moses B. Ekong

Comparative study of teratogenic potentials of crude ethanolic root bark and leaf extract of Rauwolfia vomitoria (apocynaceae) on the fetal heart

Background: Rauwolfia vomitoria, a tropical shrub, is a medicinal plant used in the treatment of a variety of ailments. It is popular to the locals because of its anti-hypertensive and sedative properties. Aim: This is to find the probable teratogenic effects of ethanolic leaf and root bark extracts of Rauwolfia vomitoria on the morphological and histological features of the fetal heart. Material and Methods: Twenty five female rats weighing between 170-200g were used for this study. The rats were divided into five groups labeled A, B, C, D and E, with each group consisting of five rats. Pregnancy was induced by caging the female rats with sexually matured males. The presence of vaginal plug and tail structures in the vaginal smear the following morning confirmed coition, and it was regarded as day 0 of pregnancy. Group A was given sham treatment of distilled water. Group B and C received respectively 150mg/kg and 250mg/kg body weight doses of ethanolic leaf extract of Rauwolfia vomitoria, and those in groups D and E received respectively 150mg/kg and 250mg/kg body weight doses of ethanolic root bark extract of Rauwolfia vomitoria. These treatments were on days 7-11 of gestation (5 days) with the aid of an orogastric tube. On the day 20 of gestation, the rats were sacrificed and the fetuses examined for gross anomalies, preserved and latter process for histological studies. Results: There were no mortality in this study, and no obvious gross malformations in the fetuses. Histological observations of the fetal heart showed marked distortion of the cardiac muscle nuclei and myocardial fibers in the treated groups particularly those whose mothers received 250mg/kg of the extracts. These effects were more pronounced in the groups whose mothers received the root extract when compared with the control and the groups whose mothers received the leaf extract. Conclusion: This result suggests that high doses of ethanolic leaf and root extracts of Rauwolfia vomitoria may be cardiotoxic to the developing rats heart.

Evaluation of calabash chalk effect on femur bone morphometry and mineralization in young wistar rats: A pilot study

Background: Calabash chalk, a popularly consumed geophagic material in Nigeria has been reported to contain lead, arsenic, alpha lindane, endrin, and endosulfan 11 among other pollutants. Aim: The continuous exposure of young children to this chalk necessitated this study on the bone morphometry and mineralization in young Wistar rats. Materials and Methods: Fourteen young (weanling) Wistar rats of both sexes weighing 54-72 g were assigned into two groups of seven animals each. Group I served as control, while group II was the test group (TG). 40 mg/ml of C. chalk was administered as suspension to the test animals in group II. Animals in the control group were orally treated with 1ml of distilled water. Administration of the C. chalk in the animals lasted for 28 days, and the animals were sacrificed on day 29, using chloroform anaesthesia. The femur bones were dissected out, cleaned of flesh and sun-dried. The lengths and weights of the femur bones were measured using graphite furnace atomic mass spectrophotometer. Results: Results showed 1.6% decrease in body weight change in the TG, insignificant decreases in the weights and lengths of both the right and left femur bones, and significant decreased (P < 0.0126) organ-somatic index, and femur bones concentrations (mg/l) of zinc, phosphate, carbonate, calcium, sodium, and potassium (P < 0.05). Conclusion: In conclusion, this study showed that C. chalk may alter growth rate, and cause de-mineralization in the femur bone, hence, it may be detrimental to bone growth.

Hormonal and Histomorphologic Effects of Azadirachta indica leaf Extract on the Pars Anterior of Wistar Rats

Azadirachta indica es un arbol cuyo valor medicinal es invaluable. Cualquier parte del arbol se puede utilizar en el tratamiento de la infeccion por malaria. Reportes han indicado su efecto antifertilidad, lo que requirio estudiar los efectos del extracto metanolico de la hoja sobre los niveles sericos de las hormonas luteinizante (LH) y foliculo estimulante (FSH) y la histomorfologia de la pars anterior de ratas Wistar. Treinta ratas Wistar adultas fueron divididas en tres grupos. El grupo A fue utilizado como control y los animales recibieron agua destilada por via oral, mientras que los grupos B y C fueron tratados con 200 mg/kg y 400 mg/kg respectivamente, con extracto de hoja mediante una sonda nasogastrica durante catorce dias. A los quince dias, los animales fueron sacrificados por anestesia con cloroformo. Se obtuvo sangre desde sus corazones, mientras que el craneo fue abierto para evaluar la hipofisis. Los ensayos hormonales mostraron que los niveles en suero de la LH y FSH se redujeron en los grupos B y C, tratados con 200 mg/kg y 400 mg/kg respectivamente, siendo la reduccion de LH significativa (p<0,001). Secciones histomorfologicos de la pars anterior revelaron una reduccion de las poblaciones acidofilas y basofilas, con prominentes cromofobos degranulados que fueron mayores en el grupo tratado con 400 mg/kg del extracto de A. indica. Este grupo tambien presento hipertrofia de los basofilos en comparacion con el control. En conclusion, el extracto alcoholico de la hoja de de A. indica disminuye el nivel serico de LH y FSH y provoca cambios histomorfologicos en la pars anterior de ratas Wistar adultas.

Rauwolfia vomitoria inhibits olfaction and modifies olfactory bulb cells.

The rising cost of orthodox medication has endeared so many to the use of herbs for the management of neurological conditions. Rauwolfia vomitoria (RV) one of such herbs is a rainforest shrub whose parts are used locally in the management of psychiatry and other medical issues. Its usefulness though not in doubt is wrapped with adverse reports as its active constituents depletes brain monoamine and dopamine stores. This motivated this research on the effects of the root bark extract on olfaction and the olfactory bulb of adult Wistar rats. Eighteen adult Wistar rats (220g average) were divided into three groups (n=6); control (placebo), 200mg/kg and 400mg/kg RV root bark extract, respectively. The oral administration lasted for seven days and on day 8, test of olfaction was carried out and the animals immediately anaesthetized with ketamine hydrochloride (i.p.) and perfuse-fixed with 10% neutral buffered formalin. All the brains were processed for histology and immunoreactivity. Results showed loss of body weights and olfaction in the 200mg/kg and 400mg/kg RV groups. There was hypertrophy and atrophy of mitral cells respectively, in the 200mg/kg and 400mg/kg RV groups, while there was hyperplasia of cells in the internal granular and plexiform layers of both groups. There was decreased neuron specific enolase (NSE) and neurofilament (NF) expression in the 200mg/kg RV group, while NF and glial fibrillary acidic protein (GFAP) expression was decreased in the 400mg/kg RV group. However, NSE expression was enhanced in the 400mg/kg group, while GFAP expression was enhanced in the 200mg/kg RV group. These results suggest that these doses of RV affect olfaction and appetite, and stimulate adverse cellular changes in the olfactory bulb.

Rauvolfia vomitoria and Gongronema latifolium stimulate cortical cell proliferations

Introduction: Rauwolfia vomitoria (RV) and Gongronema latifolium (Gl) are herbs with closely related and diverse medicinal properties. The combination of both plants is reported to have the potentials for brain functions and structure protection. Aim: This study therefore investigated the interaction of these herbs on the histomorphology of the cerebral cortex of mice. Materials and Methods: 24 male Wistar mice of body weight 15-26 g were divided into 4 groups. The mice were administered respectively, 0.5 mL of Tween 20, 150 mg/kg of R. vomitoria, 200 mg/kg of G. latifolium, and a combination of 150 mg/kg of R. vomitoria and 200 mg/kg of G. latifolium (RV+GL), orally, and daily for seven days. On day 8, the animals were sacrificed and their brains preserved, and the cerebral cortices were excised for routine histology. Cellular densities were quantified using ImageJ™. Results: All the groups gained body weight, which was however lower in the test groups compared with the control group. No difference was observed in whole brain weight in all the experimental groups, while histomorphological studies of the cerebral cortex showed higher cellular density and smaller cellular sizes in the RV, GL and RV+GL groups. The RV+GL group also showed slightly larger cells in the cortical plate compared with the control group. The mean cellular population of sections of the cerebral cortex were also higher in test groups RV and GL, but not the RV+GL group. Conclusion: This study showed that R. vomitoria root bark and G. latifolium leaf extracts either singly or in combination may stimulate cellular proliferation at the given dose, which may serve a protective or deleterious role.

Effect of Preconception Gamma Irradiation on Morphometric Assessment of Adult Female Mice and Embryo

El objetivo fue estudiar el efecto de la irradiacion gamma antes de la concepcion sobre la morfometria macroscopica de ratones hembra adultos y los embriones de sus crias. Veinte y siete ratones, 18 hembras y 9 machos, divididos en 3 grupos (control, sin irradiacion e irradiado) con 6 hembras y 3 machos cada uno en proporcion 2:1. Una dosis de radiacion gamma de 1 Gy/min fue aplicada a uno de los ratones expuestos por un equipo Cobalt 60, Theratron modelo 780c, Atomic Energy of Canada Limited (AECL) en el departamento de radioterapia del Hospital University College de Ibadan. Todos los animales se aparearon 1 semana despues de la irradiacion. Se confirmaron los tapones vaginales, y las hembras prenadas fueron sacrificadas en el dia 14 de la gestacion por inhalacion de cloroformo. La morfologia general de los ratones hembras y sus camadas fueron evaluadas y analizadas estadisticamente. Un total de 113 embriones se recolectaron en todos los grupos, 54 del grupo control, 50 del grupo no irradiados y 9 del grupo irradiado. Las evaluaciones morfologicas macroscopicas de los fetos fueron estadisticamente significativas (p<0,05) para los 3 grupos de comparacion. Estos hallazgos sugieren que una irradiacion previa a la concepcion afecta a la morfologia de los ratones hembra y su progenie.

Stavudine, an anti-retroviral drug induces reactive astrocytes in motor cortex of albino mice

Objectives: Anti-retroviral (ARV) drugs are medications used for the treatment and management of retrovirus infections. Stavudine, one of the commercially available ARVs, is a synthetic ARV agent active against the human immunodeficiency virus type 1. In this study, the effect of stavudine on reactive astrocytes on the motor cortex of albino Wistar mice was investigated. Materials and Methods: Twenty-four albino mice weighing 30 g on the average were equally assigned into three groups, A, B and C (i.e., eight mice in each group). Group A served as the control, while Groups B and C were the experimental groups. Group B received 0.6 mg/kg of stavudine, while Group C received 1.2 mg/kg of stavudine by orogastric tubes twice a day for 21 days. No treatment was given to the control group, and all the animals received feed and water ad libitum throughout the experimental period. Results: Light microscopic study of the reactive astrocytes in the motor cortex of mice revealed few astrocytes stained black in the control group, Groups B and C revealed a significantly (P < 0.05) higher reactive astrocytes population, with Group C (P < 0.05) having higher reactive astrocytes population compared to Group B. Conclusions: These results revealed that stavudine caused hyperplasia of astrocytes in the motor cortex of albino mice, and this may affect astrocyte activity and consequently impair motor functions. The effect was dose dependent.