Rebaudioside A inhibits pentylenetetrazol-induced convulsions in rats

AbstractThe safety of patients with epilepsy consuming sweetening agents, which is becoming increasingly prevalent for various reasons, is a topic that should be emphasized as sensitively as it is for other diseases. Patients with epilepsy consume sweetening agents for different reasons such being diabetic or overweight. They can occasionally be exposed to sweetening agents unrestrainedly through consuming convenience food, primarily beverages. This study aimed to investigate the effects of rebaudioside A (Reb-A), which is a steviol glycoside produced from the herb Stevia rebaudiana (Bertoni), on epileptic seizures and convulsions induced by pentylenetetrazole (PTZ). Forty-eight male rats were used. Twenty-four rats were administered 35 mg/kg PTZ to trigger epileptiform activity; the remaining 24 rats were administered 70 mg/kg PTZ to trigger the convulsion model. The epileptiform activity was evaluated by spike percentage, whereas convulsion was evaluated by Racine's Convulsion Scale and the onset time of the first myoclonic jerk. Statistical analysis revealed a statistically significant decrease in the Racine's Convulsion Scale score and increase in the latency of first myoclonic jerk in a dose-dependent manner for the rat groups in which PTZ epilepsy had been induced and Reb-A had been administered. For the groups that were administered Reb-A, the spike decrease was apparent in a dose-dependent manner, based on the spike percentage calculation. These results indicated that Reb-A has positive effects on PTZ-induced convulsions

UV-B induces cell death in the lichen Physcia semipinnata (JFGmel)

WOS: 000289045600002We have examined the consequences of Ultraviolet-B (UV-B) irradiation in the thallus of the lichen Physcia semipinnata (J.F.Gmel) in terms of cell viability and apoptotic-like formation. UV-B induced oligonucleosomal DNA fragmentation was detected by TUNEL assay and this is the first study showing DNA fragmentation in thalli. The intensity of TUNEL-positive cells after exposure to UV-B at doses up to 95.9 J/cm(2) was higher in the photobiont layer than the mycobiont layer

Neural stem cell therapy in neurological diseases

WOS: 000271668400002Early developmental process of mammalian embryo is almost completely directed by the behavior of stem cells, which is controlled by both environmental and intrinsic factors. These cells commonly subject to dividing, migration, deterioration or death. Comparing to all other tissues in the body, central nervous system has a considerably limited capacity to regenerate. Recent knowledge on neural stem cells has brought novel approaches as to the use of stem cells in the treatment of some neurodegenerative disorders such as Parkinson, Alzheimer disease and amyotrophic lateral sclerosis, as well as in the management of spinal cord injuries. However, scientific literature requires detailed information regarding the proliferation and differentiation of stem cells and the mechanisms controlling the migration of these cells to the targeted central nervous system site. Development of new therapeutic protocols using stem cells and their effective clinical application in the future would bring light to cope with a number of systemic diseases, especially neurological disorders. This review has considered the biological features of stem cells, stem cell plasticity, potential application of stem cells in neurological diseases and cancer, highlighting the promises as well as the problems of this treatment approach

The Relationship between Melatonin and Cannabinoid-1 Receptor in Cortical Dysplasia Generated Rats

WOS: 000343369600016Objectives: Cortical dysplasia is a developmental malformation that occurs as a result of defects in neuronal proliferation, migration and organization during the formation of brain cortex layers. Cannabinoid-1 Receptor (CB1R) plays a role in brain cortex development. Melatonin neuroprotective is an agent. In this study using an experimental cortical dysplasia model, CB1R expression and the effect of melatonin on CB1R were investigated. Methods: Eighteen female Wistar albino rats were randomly divided into three groups (n=6). A single dose of intraperitoneal (i.p) saline (20 ml/kg) was administered in the 15th day of pregnancy in the rats group 1 (sham group). A single dose of i.p BCNU (20 mg/kg) was administered in the 15th day of pregnancy in the rats in group 2 (BCNU) and group 3 (BCNU+ Melatonin). In addition, i.p melatonin (10 mg/kg) starting on day 15 of pregnancy and continuing until the day of delivery were administered to the rats in group 3 (BCNU+ Melatonin). Newborn brain sections were investigated using Luxol fast blue and anti-CB1R staining. Results: While the sham group had cerebral cortex stratification compatible with the normal newborn histology, it was observed that the stratification was disrupted in the group 2 and group 3. In the observed brain regions (cerebral cortex, cerebellar cortex and hippocampus), it was observed that CB1R immunoreactivity decreased in group 2 and 3. Conclusion: In an experimental cortical dysplasia model, it was seen that the administration of melatonin revealed a protective effect against the decrease in CB1R expression. It has been suggested that a decrease in CB1R expression would also play a role in cortical dysplasia formation mechanisms

Melatonin Attenuates Histopathological Changes in the Hippocampus of Infantile Rats with Kaolin-Induced Hydrocephalus

WOS: 000435963700003PubMed ID: 29791910Objective/Aim: Hydrocephalus is defined as an incapacitating neurological disorder characterized by ventricular enlargement in children, but the effects of melatonin on this hydrocephalus have not yet been fully elucidated. In the present experiment, we attempted to investigate the effects of exogenous melatonin administration on hydrocephalus-induced hippocampal changes in infantile rats. Methods: In this study, we randomly divided 45 Swiss albino rats aged 2 weeks into 3 groups: group I, the control group received a sham injection with needle insertion only; groups II and III were given kaolin injections before treatment - group II, the hydrocephalus group, was treated with an isotonic NaCl solution, and group III, the hydrocephalus plus melatonin group, was treated with 0.5 mg/100 g body weight of exogenous melatonin. Both immunohistochemical and histological analyses were performed after hydrocephalus induction and melatonin administration. Immunohistochemical staining consisted antiglial fibrillary acidic protein staining. The TUNEL technique was used for defining quantitate apoptosis. Results: Melatonin administration significantly attenuated chronic hydrocephalus-induced histopathological changes in the hippocampal subregions of infantile rats. Compared to hydrocephalic rats treated with saline solution, melatonin significantly decreased the number of apoptotic cells and pyknotic index values of each hippocampal subregion after the kaolin-induced hydrocephalus (p < 0.001). Conclusion: The present results demonstrate that the chronic hydrocephalus-induced histopathological changes in the hippocampus were partially reversible with melatonin treatment, suggesting its neuroprotective effects in infantile rats. However, these findings need to be confirmed by further experimental studies and clinical trials. (C) 2018 S. Karger AG, Base

Effects of Melatonin on the Cerebellum of Infant Rat Following Kaolin-Induced Hydrocephalus: a Histochemical and Immunohistochemical Study

WOS: 000393586100016PubMed ID: 27113349Hydrocephalus is a developmental disorder causing abnormally collected cerebrospinal fluid within the cerebral ventricles. It leads to bigger skulls and many dysfunctions related to the nervous system. Here, we addressed whether exogenous melatonin administration could reverse the clinical features of kaolin-induced hydrocephalus in infantile rats. A controlled double-blinded study was conducted in 2-week-old 45 Wistar albino rats, which were divided into three groups: Group A, the control group, received intracisternal sham injection with solely the needle insertion; group B, the hydrocephalus group, was treated with isotonic NaCl after kaolin injection; and group C, the hydrocephalus + melatonin group, was given i.p. exogenous melatonin at a dose of 0.5 mg/100 g body weight after kaolin injection. Histological and immunohistochemical analyses were performed after the induction of hydrocephalus and melatonin administration. Glial fibrillary acidic protein was stained by immunohistochemical method. TUNEL method was used to define and quantitate apoptosis in the cerebellar tissues. Statistical analysis was performed by nonparametric Kruskal-Wallis H test, and once significance was determined among means, post hoc pairwise comparisons were carried out using Mann-Whitney U test. We found that melatonin administration significantly ameliorated ratio of substantia grisea area/substantia alba area in the cerebellum of infantile rats. Histologically, there was a significant reduction in the number of cerebellar apoptotic cells after the hydrocephalus induced by kaolin (P < 0.05). Our results clearly revealed that the histopathological changes in the cerebellum were reversed by systemic melatonin administration in infantile rats with kaolin-induced hydrocephalus. Nevertheless, further studies are needed to suggest melatonin as a candidate protective drug in children with hydrocephalus

Traction Vasculogenesis: Experimental Vessel Elongation by Traction in Rat Model

WOS: 000462822700002Background: Microsurgeons may face inadequate vessel length in traumatic or post-resection vascular defects and flap surgery. As tissue regeneration by mechanical forces is possible like in tissue expansion and distraction osteogenesis, we questioned the effect of traction forces on isolated vessels, generated by an internal maxillary distraction device to overcome such problem. Methods: 30 Wistar-Albino rats were randomized in two groups as control and traction. By an internal maxillary distraction device placed subcutaneously to abdominal region, femoral artery and vein of traction group were applied daily traction for 10 days perpendicular to their course. Control group received the same procedure but no traction was applied. Vessel length, blood flow and histologic and microangiographic changes were evaluated on postoperative 11th day. Results: Final length of vessels was found to be higher in the traction group (21.93 mm) compared to control group (12.86 mm). (P = 0.000) Blood-flow patency rate of artery and vein was found 100 % in control group (n = 15) and 80 % in experiment group (n = 12). Microangiographic study showed patent blood flow in both control and traction groups. Histologic evaluation showed vascular wall thickening, perivascular adipocyte and neutrophil infiltration and vein lumen enlargement compared to control group. Conclusion: The preliminary "traction vasculogenesis" technique is found to be a promising technique to gain vessel length in vascular shortness problems. With further studies and refinements this technique may be carried to clinical applications in cases of vascular inadequacy

Investigation of maternal melatonin effect on the hippocampal formation of newborn rat model of intrauterine cortical dysplasia

WOS: 000284470700019PubMed ID: 20461523Objectives Cortical dysplasia is a cortical malformation resulting from any developmental defects during different periods of development. This study aims to investigate the hippocampal histopathological alterations in the neonates with cortical dysplasia due to the prenatal exposure to carmustine (1,3-bis (2-chloroethyl)-1-nitrosoure; BCNU) and the possible effects of prophylaxis with melatonin, a neuroprotective agent. Methods Wistar albino female rats were randomly divided into four experimental groups; control, melatonin-treated, BCNU-exposed and BCNU-exposed+melatonin-treated. Light microscopy and immunohistochemistry were carried out on the newborn hippocampus. Results Histopathology of hippocampus from the control and melatonin-treated groups showed continuity of migration and maturation as patognomonic signs of the normal newborn hippocampus. Hippocampal cortex from the newborns exposed in utero to BCNU showed the histology of early embryonic hippocampal formation with immuno-histochemical increase in the number of nestin positive cells and decreases in the immunoreactivity of glial fibrillary acidic protein (GFAP) and synaptophysin. These findings indicate a significant delay in hippocampal maturation, migration, and synaptogenesis. Intrauterine treatment of BCNU-exposed rats with melatonin resulted in histopathological features almost similar to control group. Conclusion It has been concluded that cortical dysplasia induced by intrauterine BCNU administration results in delayed hippocampal maturation, which is successfully restored by intrauterine melatonin treatment