Olatunde Owoeye

Antioxidative and Chemopreventive Properties of Vernonia amygdalina and Garcinia biflavonoid

Recently, considerable attention has been focused on dietary and medicinal phytochemicals that inhibit, reverse or retard diseases caused by oxidative and inflammatory processes. Vernonia amygdalina is a perennial herb belonging to the Asteraceae family. Extracts of the plant have been used in various folk medicines as remedies against helminthic, protozoal and bacterial infections with scientific support for these claims. Phytochemicals such as saponins and alkaloids, terpenes, steroids, coumarins, flavonoids, phenolic acids, lignans, xanthones, anthraquinones, edotides and sesquiterpenes have been extracted and isolated from Vernonia amygdalina. These compounds elicit various biological effects including cancer chemoprevention. Garcinia kola (Guttiferae) seed, known as “bitter kola”, plays an important role in African ethnomedicine and traditional hospitality. It is used locally to treat illnesses like colds, bronchitis, bacterial and viral infections and liver diseases. A number of useful phytochemicals have been isolated from the seed and the most prominent of them is the Garcinia bioflavonoids mixture called kolaviron. It has well-defined structure and an array of biological activities including antioxidant, antidiabetic, antigenotoxic and hepatoprotective properties. The chemopreventive properties of Vernonia amygdalina and Garcinia biflavonoids have been attributed to their abilities to scavenge free radicals, induce detoxification, inhibit stress response proteins and interfere with DNA binding activities of some transcription factors.

Neurotoxicity of Nigerian bonny light crude oil in rats

Biometal accumulation may contribute to organ toxicity in individuals using the Nigerian bonny light crude oil (BLCO) for ailment management. We assessed the levels of biometals, antioxidant status, along with histomorphometric analysis to investigate the effect of BLCO, commonly use in folklore medicine, on the brain. Adult male Wistar rats were dosed by gavage with BLCO at 0, 200, and 800 mg/kg–1 of BLCO for 7 days. Results showed the accumulation of iron, zinc, nickel and lead, in contrast to copper, in BLCO-treated rats. Administration of BLCO disrupted the brain’s antioxidant system and significantly increased levels of hydrogen peroxide and lipid peroxidation. Although the Purkinje layer and maximum width of Purkinje cells were not affected, BLCO treatment significantly decreased molecular layer, granular layer, and density of Purkinje cells of the cerebellum. The neurotoxicity of BLCO may be the result of oxidative stress resulting from loss of biometal homeostasis as well as toxicant injury from other constituents of BLCO.

A Comparison of the Effect of Chlorhexidine, Tap Water and Normal Saline on Healing Wounds

En la actualidad, diversos investigadores han propagado que el uso de antisepticos en heridas en cicatrizacion deberia, ser abandonado. Se ha encontrado que los antisepticos retardan la cicatrizacion. Soluciones inocuas, tales como, suero salino y agua corriente, estan siendo consideradas como mejores alternativas para efectos antisepticos. La clorhexidina, un antiseptico comunmente usado, es conocida por ser menos toxica sobre las celulas granulares. Basado en lo anterior, comparamos los efectos de la clorhexidina, suero salino y agua corriente en heridas en cicatrizacion. A tres grupos de ratas Wistar se les infirio heridas de 2 x 2 cm de grosor, en su flanco dorsolateral derecho. La heridas fueron cubiertas (pinceladas) con clorhexidina, solucion salina o agua corriente, segun el caso. Estas heridas fueronn examinadas cada tres dias y las mediciones del area cubierta fueron registradas desde el primero al noveno dia. La contraccion de la herida al noveno dia y el numero de dias que llevo para cicatrizar se regsitraron en los diversos grupos, analizando los resultados esatadisticamente, usando el test t- student para comparar los valores. La morfologia macroscopica tambien fue observada. Los resultados mostraron un efecto inhibidor de la clorhexidina sobre la cicatrizacion. La contraccion de la herida en el grupo con antiseptico fue menor que en los grupos con suero salino y agua corriente. El promedio de dias para cicatrizar, fue mayor en el grupo con antiseptico. Estos resultados fueron estadisticamente significativos al compararlos con los otros dos grupos. No hubo diferencias estadisticamente significativas en los valores de contraccion de la herida y rango de cicatrizacion en el grupo tratado con suero salino normal y en el con agua corriente. Desde el punto de vista macroscopico, las heridas tratadas con el antiseptico tambien tuvieron un exudado verdoso sobre su superficie al dia noveno con un tejido granular palido y hubo mayor mortalidad en este grupo

Kolaviron protects against benzo[a]pyrene-induced functional alterations along the brain-pituitary-gonadal axis in male rats.

Exposure to benzo[a]pyrene (B[a]P) is well reported to be associated with neurological and reproductive dysfunctions. The present study investigated the influence of kolaviron, an isolated biflavonoid from the seed of Garcinia kola, on functional alterations along the brain-pituitary-gonadal axis in male rats exposed to B[a]P. Benzo[a]pyrene was orally administered at a dose of 10mg/kg alone or orally co-administered with kolaviron at 100 and 200mg/kg for 15 consecutive days. Administration of B[a]P significantly (p<0.05) decreased plasma levels of pituitary hormones namely follicle-stimulating hormone (FSH) and prolactin but increased luteinizing hormone (LH) by 47%, 55% and 20.9%, respectively, when compared with the control. The significant decrease in gonadosomatic index (GSI) was accompanied by significant decrease in testosterone production and sperm functional parameters in the B[a]P-treated rats. Moreover, B[a]P-treated rats showed significant elevation in the circulatory concentrations of pro-inflammatory cytokines and oxidative stress indices in the brain, testes and sperm of B[a]P-treated rats. Light microscopy revealed severe necrosis of the Purkinje cells in the cerebellum, neuronal degeneration of the cerebral cortex, neuronal necrosis of the hippocampus and testicular atrophy in B[a]P-treated rats. Kolaviron co-treatment significantly ameliorated B[a]P mediated damages by suppressing pro-inflammatory mediators and enhancing the antioxidant status, neuroendocrine function, sperm characteristics and improving the architecture of the brain and testes in B[a]P-treated rats. The findings in the present investigation highlight that kolaviron may be developed to novel therapeutic agent against toxicity resulting from B[a]P exposure.

Kolaviron and vitamin E ameliorate hematotoxicity and oxidative stress in brains of prepubertal rats treated with an anticonvulsant phenytoin

Abstract Phenytoin (PHT), an anticonvulsant agent, widely used for the treatment of epilepsy has been reported to exhibit toxic side effects. The present study investigated the protective effects of kolaviron and vitamin E on hematotoxicity and neurotoxicity induced by phenytoin, in prepubertal male rats. The animals were treated with PHT (75 mg/kg) separately or in combination with either kolaviron (200 mg/kg) or vitamin E (500 mg/kg) for 14 days. Phenytoin treatment significantly decreased the hemoglobin, white blood cells, lymphocytes and mean corpuscular volume levels without affecting red blood cell, packed cell volume, neutrophils, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration when compared with the control rats. There was a significant increase in lipid peroxidation and hydrogen peroxide levels with marked depletion in antioxidant status in brains of PHT-treated rats when compared with the control. Although PHT treatment had no effect on the granular layer, widest diameter of Purkinje cells and Purkinje layer of the cerebellum, it significantly reduced its molecular layer and the density of Purkinje cell. Administration of PHT significantly reduced the densities of the granule cells of the dentate gyrus and the pyramidal neurons of the cornu ammonis of hippocampus proper. Co-treatment with kolaviron and vitamin E effectively reversed the PHT-mediated alterations in the hematology, brain antioxidant status and histomorphometry when compared to PHT only. Taken together, the present data indicate the abilities of kolaviron and vitamin E to ameliorate phenytoin-induced hematotoxicity and oxidative stress in brains of rats.

Evaluation of adaptogenic-like property of methyl jasmonate in mice exposed to unpredictable chronic mild stress.

This study was undertaken to evaluate the adaptogenic-like activity of methyl jasmonate (MJ) in mice exposed to unpredictable chronic mild stress (UCMS). Male Swiss mice were treated with MJ (25-100mg/kg, i.p.) 30 min before exposure to UCMS daily for 14 days prior to testing for memory and anxiety. Thereafter, the blood glucose and serum corticosterone levels were estimated using glucometer and ELISA. The brain concentrations of malondialdehyde (MDA) and glutathione (GSH) were estimated using spectrophotometer. Brain histology and the population of healthy neurons in the hippocampal regions were also assessed. MJ reversed anxiety and memory impairment produced by UCMS, which suggest adaptogenic-like property. The reduction in the weight of adrenal gland and liver in MJ-treated groups further indicates adaptogenic activity. It further decreases the blood glucose and serum corticosterone levels in UCMS-mice. Also, MJ decreases the concentrations of MDA and elevated the levels of GSH in the brain of mice exposed to UCMS. Brain histology revealed that MJ attenuated UCMS-induced degeneration and death of neuronal cells in the pyramidal layer of the cornu ammonis 3 (CA3) and the sub-granular zone of the dentate gyrus of the hippocampus. Moreover, MJ decreased the population of dead neuronal cells of the pyramidal layer of the CA3 and the sub-granular zone of the dentate gyrus of the UCMS-mice, which suggests neuroprotection. Taken together, these findings suggest that MJ demonstrated adaptogenic-like activity in mice; which might be related to modulation of serum corticosterone levels, inhibition of oxidative stress and neuroprotection.

Radiation Nephritis: Anti-inflammatory Effect of Dexamethasone in Adult Wistar Rats (Rattus norvegicus)

Fue estudiado el efecto anti-inflamatorio de la dexametasona en rinones irradiados de 18 ratas Wistar adultas (Rattus norvegicus). Luego de la aclimatizacion, aleatoriamente se dividieron en 3 grupos de 6 animales por grupo. El grupo control recibio una solucion salina normal, sin recibir drogas ni radiacion. El segundo grupo recibio solucion salina normal y radiacion. El tercer grupo recibio tratamiento previo con dexametasona con 1 mg / kg de peso corporal / dia, durante 2 dias, seguido de radiacion. Los animales fueron expuestos a radiacion con una fraccion independiente de 2.5 Gy de rayos gamma por una fuente de Cobalto-60, usando una maquina de teleterapia AECL Theatron 780-C. Despues de la exposicion a las diferentes intervenciones, los animales fueron sacrificados el dia 14 post-irradiacion y los rinones de cada uno de los animales fueron disecados. Los tejidos renales fueron sometidos a procesamiento histologico, y luego se estudiaron utilizando un objetivo ocular milimetrado calibrado a 2mm para el estudio histomorfometrico. Se demostro que todos los animales irradiados sufrieron perdida de peso 14 dias despues de esta (p <0.05), independientemente de los tratamientos adicionales con dexametasona , siendo estadisticamente significativo. La histomorfometria mostro que el ancho maximo de la capsula glomerular fue significativamente mayor en los grupos irradiados que en el control en p <0.05. El diametro maximo del glomerulo fue significativamente mayor en los animales irradiados en comparacion con los animales control p <0.05. Los resultados de este estudio mostraron que la administracion intraperitoneal, de 1 mg / kg de peso corporal / dia durante 2 dias, de dexametasona antes de comenzar el tratamiento con irradiacion, no impide la perdida de peso ni permite aliviar el edema de los nefrones, injuria producto de la radiacion a las Ratas Wistar.

Modulatory Role of Kolaviron in Phenytoin-Induced Hepatic and Testicular Dysfunctions in Wistar Rats

ABSTRACT Phenytoin, an anticonvulsant agent used for the treatment of epilepsy has been reported to exhibit toxic side effects on the liver and testes. The present study investigated the protective effects of kolaviron (KV, a bioflavonoid from Garcinia kola seeds) against hepatic and testicular damage in rats exposed to phenytoin. The study consisted of four groups of six rats per group. Group I rats received 2 mL/kg of corn alone while group II received 75 mg/kg of phenytoin (PHT) alone. Groups III and IV were co-treated with kolaviron (200 mg/kg KV) and vitamin E (500 mg/kg VTE), respectively, for 14 days. The antioxidant status, hepatic and reproductive functional parameters were subsequently determined. PHT treatment significantly (p < 0.05) increased superoxide dismutase (SOD) and catalase (CAT) activities, elevated lipid peroxidation (LPO) and hydrogen peroxide (H2O2) levels along with significant reduction in the hepatic and testicular levels of glutathione (GSH). Moreover, PHT exposure elicited significant increases in alkaline phosphatase (ALP) and aspartate aminotransferase (AST) levels. The significant reduction in seminal epithelium thickness and the diameter of seminiferous tubules was accompanied with marked decrease in sperm motility, sperm count, and viability in PHT-treated rats. However, antioxidant status and the functional indices of liver and testes were restored to near control levels in rats co-treated with KV and VTE. In conclusion, KV and VTE protect the liver and testes against functional impairment due to PHT treatment.

The Neurotoxic Effects of Artemether on the Cytoarchitecture of the Trapezoid Nuclei of Adult Male Wistar Rats (Rattus novegicus)

En el Hombre, el artemeter es dado en el tratamiento de la malaria en dosis de 160 mg/kg de peso, por tres dias. Este estudio abordo los efectos de un tratamiento con artemeter, durante 7 dias (en dosis de 1,23 mg/kg de peso) sobre el nucleo trapezoide de ratas y las funciones de conducta, en el dia 7 despues de la administracion de la droga. No se observaron ni macro ni diferencias morfologicas entre dos grupos de animales (grupos control y experimental) en el dia 7 de la completacion del procedimiento. Un incremento estadisticamente significativo en el promedio del peso del cuerpo fue encontrado en el grupo control C1 (el que recibio solamente una dieta standard y agua) y C2 (que recibio 1,23 mg/kg de peso de solucion salina intramuscular agregada a la dieta y al agua) que fue desde 140± 19,65 g y 146 ± 19,9 g en el dia 1, respectivamente y de 151 ± 12 g y de 156,2 ± 12,2 g en el dia 7, respectivamente. No hubo una reduccion aparente estadisticamente significativa en el peso del cuerpo del grupo experimental (el cual recibio inyeccion intramuscular de 1,23 mg/kg de peso de artemeter), la que fue desde 160 ± 9 g en el dia 1 y de 157,4 ± 8, en el dia 7. La evaluacion de nucleos del tronco encefalico mostro apariencia cromatica irregular de las neuronas del nucleo trapezoide en el grupo experimental contrariamente a la apariencia vesicular normal de las neuronas de este nucleo en el grupo control. Las ratas de los grupos controles C1 y C2 presentaron un normal balanceo y coordinacion, mientras que las ratas del grupo experimental, mostraron anormalidades de balanceo y coordinacion. Usando el test t con 95% de intervalo de confianza, p 0,05 y con un valor p=2,26, no se observaron diferencias estadisticamente significativas entre el promedio de los grupos C1 y C2 y del grupo experimental

Renal Corpuscles Were Protected From Dichlorvos: Induced Morphological Alterations in Rats by Antioxidant Vitamins

El diclorvos (DDVP), un pesticidas organofosforado, es un compuesto volatil que entra en el cuerpo humano a traves de la via oral, dermica y por rutas inhalacion, excretandose por via renal. Este estudio evaluo los efectos histologicos del DDVP sobre el rinon. Veinticinco ratas machos (75,05±5,55 g) se dividieron en 5 grupos de 5 ratas cada uno: grupo no expuesto, expuesto a DDVP durante 5 semanas, y otros 3 grupos expuestos a DDVP durante 5 semanas, suplementados con vitamina E (VTE), vitamina C (VTC) y aceite de palma roja (APR). Las ratas fueron expuestas a DDVP en jaulas de carton con poca ventilacion por 4 horas diarias. Al termino de la exposicion, las ratas se sacrificaron y el tejido fue procesado para inclusion en parafina y tincion con H&E. Las alteraciones morfologicas se evaluaron mediante estudios histologicos y morfometricos utilizando reticulas y software. Los datos se analizaron con la prueba ANOVA considerado un p<0,05 como significativo. El DDVP causo una reduccion significativa (10%) en el diametro maximo glomerular y ancho maximo del copusculo renal (18%), en comparacion con las ratas no expuestas. Sin embargo, el diametro maximo glomerular fue significativamente elevado con VTE, VTC y APR en 21%, 22% y 23%, respectivamente, asi como para el ancho maximo del corpusculo renal por 17%, 19% y 20%, respectivamente. La celularidad de la red glomerular no fue afectada por el DDVP ni aumento con el tratamiento de vitamina. El DDVP inhalado provoco alteraciones histologicas en la anatomia microscopica de los corpusculos renales de rata, las que fueron mitigadas por la suplementacion de vitamina. Los datos sugieren relacion entre la exposicion prolongada a DDVP y la etiologia de la insuficiencia renal.