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Złożony proces karcinogenezy podlega wpływom wielu czynników, które ułatwiają lub utrudniają inicjację i promocję procesów nowotworowych. Zmieniające się pod wpływem aktywności fizycznej stężenia hormonów mogą oddziaływać na środowisko wewnętrzne organizmu człowieka, modulując ryzyko pojawienia się transformacji nowotworowej. W pracy opisano wpływ aktywności fizycznej na profile: insuliny, insulinopodobnych czynników wzrostu (IGF), IGFBP, leptyny i steroidów płciowych oraz mechanizmy ich oddziaływania na procesy nowotworzenia.
Leki roślinne są często stosowane w terapii schorzeń układu oddechowego. Gdy są przyj­mowanie jednocześnie z lekami konwencjonalnymi, zwiększa to ryzyko wystąpienia inter­akcji ze składnikami farmakologicznie czynnymi roślin leczniczych. Na podstawie zarówno wyników badań klinicznych, jak i doświadczeń przedklinicznych omówiono najczęściej używane preparaty pochodzenia roślinnego. Przedstawiono najczęstsze interakcje wpływające w znacznym stopniu na przebieg terapii schorzeń układu oddechowego.
Curcumin is a yellow pigment extracted from the rhizome of Curcuma Longa. It has been used in Asia for several thousand years as a spice, antibacterial, anti-inflammatory and digestive agent. Current research reports that curcumin exhibits antioxidative, anticancer and neuroprotective properties. The aim of this study was to compare the activity of catalase (CAT), glutathione S-transferase (GST) and arginase (ARG) in the rat kidney, heart and skeletal muscle during aging, as well as to determine the effect of systematic curcumin supplementation on the activity of the above enzymes in old animals. Studies were conducted on adult (6 months of age) and old (22 months of age) Wistar Albino Glaxo males. The animals were separated into four groups of 7-8 rats each. Groups I and II were given a standard diet without curcumin, groups III and IV were on a diet supplemented with 10 and 50 mg/kg b.w. of curcumin, respectively. Ageing was observed to have no effect on CAT activity in any of the tissues under investigation, whereas GST activity decreased in both the kidney and the skeletal muscle but not in the heart. In the kidney the level of GSH significantly decreased, but ARG activity increased. After the administration of curcumin to old rats, the activities of CAT and GST increased in the kidney and the skeletal muscle, but not in the heart. The level of GSH was higher in the kidney, but ARG activity remained unchanged. Thus, curcumin supplementation has a positive effect on detoxification processes in extrahepatic tissues of old rats.
Effect of administration of the standardized extract of Ginkgo biloba leaves (EGb 761) on learning, memory and exploratory behavior was estimated in water maze and hole-board tests. Rats (18-month old) received for three months EGb 761 at doses: 50, 100 and 150 mg/kg b.w. per day. After completion of the behavioral experiment, concentrations of neurotransmitters were estimated in selected brain regions. ANOVA demonstrated significant differences in the content of monoamines and metabolites between the treatment groups compared to the control. The increased level of 5-hydroxytryptamine (5-HT) in the hippocampus and 5-HIAA (5-HT metabolite) in the prefrontal cortex correlated positively with the retention of spatial memory. Positive correlation between platform crossings in SE during the probe trial and neurotransmitter turnover suggest improvement of spatial memory. Long-term administration of Ginkgo biloba extract can improve spatial memory and motivation with significant changes in the content and metabolism of monoamines in several brain regions.
Curcumin (diferuloylmethane), a yellow poliphenol pigment isolated from rhizome of Curcuma longa, has been used throughout Asia for several thousands of years. Beside giving curry dishes their color, curcumin has been reported as an agent used in the treatment of various disorders. The aim of this study was to determine the effect of chronic curcumin administration on enzymatic and nonenzymatic protective mechanisms in the livers of aging rats. The liver was isolated from Wistar Albino Glaxo rats, age 6 and 22 months. All rats were fed a standard chow diet. Two groups of older animals were given a standard diet supplemented either with 10 mg/kg b.w. or with 50 mg/kg b.w. of curcumin powder for 10 weeks before their sacrifice. Malondialdehyde level, reduced glutathione, the activity of catalase, glutathione S-transferase, and arginase were determined. Increased lipid peroxidation was observed in old rat livers, elevated catalase and arginase activities, as well as the level of reduced glutathione in curcumin fed animals. No changes in glutathione S-transferase activity were found. It may be concluded that curcumin administered in a diet exerts an antioxidant effect and protects the liver against ammonia intoxication.
The present study was aimed to investigate the influence of multigenerational selection in the direction of low or high body weight on spatial learning and memory in mice. Light and heavy lines of rodents were selected from an outbred stock constructed from inbred strains; A/St, BN/a, BALB/c and C57BL/6J. Male mice selected at weaning for the low (L, n=13) or high (H, n=16) body weight for 94 generations have been evaluated for behavioral performance and cognition in the modified Morris water maze task. The unselected control line (Con, n=15) was run in parallel. Presented results lead to the conclusion that selection of mice for high and low body weight over 94 generations resulted in a significant differentiation in learning abilities. Our findings suggest improvement of learning of the hidden platform position in heavy line of mice.
Introduction. Royal Jelly (RJ) is a popular bee-derived product used widely in European and Asian traditional medicine. RJ has some pharmacological activities to support health and longevity as well as prevent ageing. Objectives. To evaluate whether a short-term 6-day Royal Jelly administration is able to induce behavioural and neurochemical effects in aged rats. Materials and method. RJ (previously chemically characterized by GC-FID and GC–MS) was given to 18-month-old male Wistar rats (100 and 500mg of powder/kg b.w./day) in subcutaneous injection for 6 days. Spatial memory was assessed in a water maze. Afterwards, the level of neurotransmitters, their metabolites and turnover in the selected brain regions were estimated by HPLC. Results. Short-term RJ administration did not change spatial memory in aged rats in the water maze, although it was sufficiently active to modify most of all the serotonergic and dopaminergic transmission in the prefrontal cortex and hippocampus. Conclusion. The obtained results indicate that Royal Jelly is able to affect very quickly the neurotransmission in the brain structures responsible for cognitive performance; however, short-term administration is not sufficient to exert behavioural consequences.
The pathogenesis of non-motor symptoms in Parkinson’s disease (PD) is complex and not fully understood, but is believed to be related to the widespread nature of dopaminergic dysfunction involving structures beyond the substantia nigra. Therefore we’ve also focused in our experiments on specifi c brain regions (e.g. hippocampus and prefrontal cortex) critically involved in spatial learning and memory processes. One year old C57/BL male mice received 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrindine (MPTP) 40 mg/kg, and control group received 0.9 % NaCl. To evaluate spatial learning and memory abilities, the Morris water maze (WM) behavioral test was provided after 6 months from the intoxication. The brain concentration of monoamines: dopamine (DA), noradrenaline (NA), 5 – hydroxytryptamine (5-HT) and amino acid: glutamate (Glu) were determined by using high – performance liquid chromatography (HPLC). Statistical signifi cances differences in monoamines levels between groups were noticed in hippocampus (NA, DA content) and prefrontal cortex (NA content). We didn’t notice signifi cant differences in the WM test parameters between MPTP and the control animals. Correlation between the results of the behavioral testing in the probe trial and the level of monoamines were calculated. Swim distance to reach the hidden platform was negatively correlated with NA level in the hippocampus (rp=−0.62, P<0.05). There is need for a further investigation to confi rm the role for NA in spatial memories.
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