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The hallmarks of Alzheimer's disease (AD) pathology include senile plaques accumulation and neurofibrillary tangles, which is thought to underlie synaptic failure. Recent evidence however supports that synaptic failure in AD may instead be instigated by enhanced N-methyl-D-aspartate (NMDA) activity, via a reciprocal relationship between soluble amyloid-β (Aβ) accumulation and increased glutamate agonist. While previous studies have shown Aβ-mediated alterations to the glutamatergic system during AD, the underlying etiology of excitotoxic glutamate-induced changes has not been explored. Here, we investigated the acute effects of stereotaxic dentate gyrus (DG) glutamate injection on behavior and molecular expression of specific proteins and neurochemicals modulating hippocampal functions. Dependence of glutamate-mediated effects on NMDA receptor (NMDAR) hyperactivation was tested using NMDARs antagonist memantine. DG of Wistar rats (12-weeks-old) were bilaterally microinjected with glutamate (500 mM) with or without daily intraperitoneal (i.p.) memantine injection (20 mg/kg) for 14 days, while controls received either intrahippocampal/i.p. PBS or i.p. memantine. Behavioral characterization in open field and Y-maze revealed that glutamate evoked anxiogenic responses and perturbed spatial memory were inhibited by memantine. In glutamate-treated rats, increased NO expression was accompanied by marked reduction in profiles of glutathione-s-transferase and glutathione peroxidase. Similarly, glutamatemediated increase in acetylcholinesterase expression corroborated downregulation of synaptophysin and PSD-95, coupled with initiation of reactive astrogliosis (GFAP). While neurofilament immunolocalization/immunoexpression was unperturbed, we found glutamate-mediated reduction in neurogenic markers Ki67 and PCNA immunoexpression, with a decrease in NR2B protein expression, whereas mGluR1 remains unchanged. In addition, increased expression of apoptotic regulatory proteins p53 and Bax was seen in glutamate infused rats, corroborating chromatolytic degeneration of granule neurons in the DG. Interestingly, memantine abrogated most of the degenerative changes associated with glutamate excitotoxicity in this study. Taken together, our findings causally link acute glutamate dyshomeostasis in the DG with development of AD-related behavioral impairment and molecular neurodegeneration.

Objectives: Artificial insemination (AI) is the introduction of spermatozoa into a female's uterus or cervix for the purpose of achieving pregnancy. It is a fertility treatment for humans, in animal breeding and embryo-fetal developmental studies. This study investigated the embryo-fetal development in the rabbit via artificial insemination by evaluating the litter size, reproductive data and external morphological abnormalities after insemination. Methods:Ten adult female and three male rabbits weighing 1.8 kg and 2 kg, respectively were used. Group A served as the natural mating, while Group B served as the AI group, and the males served as semen donors. On day 28 of gestation, does were subjected to caesarean section. The ovaries and uteri were removed and examined for the number of corpora lutea and the status of all implantation. Results:Results showed a significant increase in fetal weight, total fetal number, total resorption sites, number of implantation and total number of live foetuses (p<0.05), while there was no significant increase in parameters like average fetal weight, placenta weight, uterine gravid weight, number of corpora lutea and sex ratio in Group B compared to Group A (p>0.05). A conception rate of 100% was observed in Group A compared to Group B with 80% conception rate. External examination carried out on the foetuses revealed no external abnormalities in both groups. Conclusion:The results of this study show the clear advantages in the use of rabbits for AI in terms of embryo-fetal developmental studies.

Cymbopogon citratus is a tropical phytomedicinal plant that is widely known for its hypoglycemic, hypolipidemic, anxiolytic, sedative, antioxidative and anti-inflammatory properties. In this study, we have examined the neuroprotective effects of the essential oil (ESO) of Cymbopogon citratus, following aluminum chloride (AlCl 3)-induced neurotoxicity within the cerebellum of Wistar rats. A total of 40 adult male Wistar rats were assigned into five groups and treated orally as follows: A-phosphate-buffered saline (1 ml daily for 15 days); B-ESO (50 mg/kg daily for 15 days); C-AlCl 3 (100 mg/kg daily for 15 days); D-AlCl 3 then ESO (100 mg/kg AlCl 3 daily for 15 days followed by 50 mg/kg ESO daily for subsequent 15 days); E-ESO then AlCl 3 (50 mg/kg ESO daily for 15 days followed by 100 mg/kg AlCl 3 daily for following 15 days). To address our questions, we observed the locomotion and exploratory behavior of the rats in the open field apparatus and subsequently evaluated cerebellar oxidative redox parameters, neural bioenergetics, acetylcholinesterase levels, transferrin receptor protein, and total protein profiles by biochemical assays. Furthermore, we investigated cerebellar histomorphology and Nissl profile by H&E and Cresyl violet Nissl staining procedures. ESO treatment markedly attenuated deficits in exploratory activities and rearing behavior following AlCl 3 toxicity, indicating its anxiolytic potentials. Additionally, AlCl 3 evokedincrease in malondialdehyde and nitric oxide levels, as well as repressed cerebellar catalase, glutathione peroxidase, and superoxide dismutase profiles were normalised to baseline levels by ESO treatment. Treatment with ESO, ergo, exhibits substantial neuroprotective and modulatory potentials in response to AlCl 3 toxicity.

Introduction: Chloroquine causes damage to the testis by crossing the blood testis barrier. Treculia africana has numerous medicinal potentials. However, the prevention of its complication such as male infertility remains unexplored. This aim of this study was to evaluate the effects of aqueous seed extract of Treculia africana on chloroquine-induced toxicity in the testis of adult male Wistar rats (Rattus norvegicus). Methods: Twenty eight (28) rats with an average weight 200±10g were used for the study and divided into four groups consisting of seven rats in each group. Control group A received 1 ml of distilled water daily, group B received 2mg/kg body weight daily of chloroquine orally, group C received 200mg/kg body weight daily of aqueous seed extract of Treculia Africana while group D received 2mg/kg body weight daily of chloroquine and Treculia africana seed extract (TASE) concurrently for a period of 60 days. Histological, histopathological, hormonal and semen analysis, Stereological and Imunohistochemical evaluation of the testis were done. Results: Histological analysis showed the ameliorative properties of TASE after chloroquine induced testicular toxicity. Significant differences (P<0.05) in hormonal analysis were observed across treatment groups. Significant differences (P<0.05) in Semen and Sterological analysis were observed. Johnsen's Score of the testis showed a significant improvement in group D while Immunohistochemical observation showed the ameliorative properties of TASE. Conclusion: chloroquine is injurious to male reproductive health, administration of TASE may help to improve seminiferous tubule integrity and immunohistochemistry and stereological studies further revealed its ameliorative properties.