To evaluate several cognitive parameters during the execution of behavioral tasks assessing cognitive function in laboratory animals, the parameters are reported within a range. This situation entails that each laboratory must establish the conditions under which the behavioral task to evaluate the cognitive function can be carried out. C57BL/6 and BALB/c inbred strains are used more often in behavioral studies relating to anxiety, stress, fear and cognitive function. The aim of this work was to compare the behavioral response of mice of the strains BALB/c and C57BL/6 to evaluate memory and learning as cognitive functions. Young male mice, 7–8 weeks of age, from each strain were used. Y maze, object recognition and passive avoidance tasks were performed. Both strains of mice showed differences in the response to the passive avoidance and Y maze task. This study advances knowledge about the baseline behavior of laboratory mice strains and their response during the experimental procedures, which are due to the treatment, genetic influence, procedural differences, genetic background variance, or any combination of these elements.

Dementia is defined as cognitive impairment in more than one cognitive area and leads to an abnormal degree of impairment in the ability to remember past events. Among mice models of dementia the most used strains are SAMP8 and C57BL/6. There is no reference to characterizing a model of dementia in naturally aged mice of the BALB/c strain, or to the minimum age at which these animals can be used. The aim of this study was the characterization of aged male BALB/c cenp mice as a model of dementia from the evaluation of behavioural, pathological and biochemical markers. One hundred and twenty mice were used and 10 of these were analysed from 8 to 9 months of age, and every 4 months, in a comparative way to young control animals from 4 to 5 months. At the age of 12-13 months there was cognitive impairment in the animals from the Y-maze and object recognition tests and this impairment was maintained at 16-17 months of age. An increase in oxidative damage to proteins in the brains of aged animals was also found in relation to young animals; as well as a decrease in the concentration of triglycerides. At the age of 16-17 months, a significant decrease in the size of the thymus and brain was obtained. We consider that it's a very useful option to use animals 12-13 months of age where there are symptoms of cognitive deficiency, histopathological and biochemical elements characteristic of dementia.

Background: BioCen-128 is a new active pharmaceutical ingredient composed of a specific bovine thymic fraction of a polypeptide nature. Positive results of similar thymus extracts have been shown to be effective in delaying the processes associated with aging, immunosenescence and Alzheimer's disease (AD), where the inflammation plays an important role. Because of the anti-inflammatory potential of BioCen-128, the aim of this study was to evaluate the granuloma model induced by a cotton wool implantation and the model induced by intracerebroventricular (ICV) administration of streptozotocin (STZ). Method:The experiment was carried out using male OF-1 cenp mice weighing 20 ± 2 g. Results:Mice administered BioCen-128 in via the IP route at 5, 10 and 20 mg/kg of corporal weigh showed a decrease in the wet and dry weights of the granuloma, providing evidence of a systemic anti-inflammatory effect. In the ICV model of STZ, the administration of BioCen-128 improved cognitive function. Conclusion:These responses suggested an anti-neuroinflammatory effect explainable by the action of thymosin β4 and thymosin alfa proteins. The results suggested that BioCen-128 could be used in the prevention and treatment of some diseases, for example AD, where neuroinflammation is one of the biological events that take place.

Age is the greatest risk factor for memory loss and other disorders. The aim of this paper was to investigate whether the OF1 cenp mouse was suitable for use as a model of age-induced cognitive decline. To achieve this, it was compared male OF1 cenp middle aged and aged with young mice for learning abilities and biochemical markers. It was obtained that based on the different mechanisms of memory that was evaluated in the Y-maze test, in the Morris Water Maze and in the Novel Object Task, it can be affirmed that aged male OF1 cenp mice from 7-8 months show true cognitive deficits based in the reduction of learning and memory. It was found an increase in glucose, triglycerides and cholesterol concentration in the aged mice. At the age of 7-8 and 15-16 months, a significant decrease in the size of the brain was obtained, on the contrary the liver weight does not show differences. An increase in oxidative damage and a decrease in the antioxidant total capacity in the brains of aged animals was also found in relation to young animals. The correlation of results obtained in relation to behavioral task, hematological and biochemical analyses indicate that OF1 cenp mice with 15-16 months of age are a useful model cognitive decline. It can be used to characterize this disorder during aging and evaluate nutritional supplements for its prevention.