Facultad de Ciencias de la Salud

Cocaine can induce severe neurobehavioral changes, among others, the ones involved in learning and memory processes. It is known that during drug consumption, cocaine-associated memory and learning processes take place. However, much less is known about the effects of this drug upon the mechanisms involved in forgetting.The present report focuses on the mechanisms by which cocaine affects memory consolidation of experiences acquired prior to drug administration. We also study the involvement of hippocampus in these processes, with special interest on the role of Nuclear factor kappa B (NF-κB), N-methyl-D-aspartate glutamate receptor 2B (GluN2B), and their relationship with other proteins, such as cyclic AMP response element binding protein (CREB). For this purpose, we developed a rat experimental model of chronic cocaine administration in which spatial memory and the expression or activity of several proteins in the hippocampus were assessed after 36 days of drug administration. We report an impairment in memory acquisition of experiences gathered prior to cocaine administration, associated to an increase in GluN2B expression in the hippocampus. We also demonstrate a decrease in NF-κB activity, as well as in the expression of the active form of CREB, confirming the role of these transcription factors in the cocaine-induced memory impairment.

Aims. The main goal of this study was to evaluate the presence of oxidative damage and to quantify its level in gestational diabetes. Methods. Thirty-six healthy women and thirty-six women with gestational diabetes were studied in the three trimesters of pregnancy regarding their levels of oxidative stress markers. These women were diagnosed with diabetes in the second trimester of pregnancy. Blood glucose levels after 100g glucose tolerance test were higher than 190, 165 or 145 mg/dl, 1, 2 or 3 hours after glucose intake. Results. The group of women with gestational diabetes had higher serum malondialdehyde levels, with significant differences between groups in the first and second trimester. The mean values of serum glutathione peroxidase activity in the diabetic women were significantly lower in the first trimester. In the group of women with gestational diabetes there was a negative linear correlation between serum malondialdehyde concentration and glutathione peroxidase activity in the second and third trimester. Conclusions. In this observational and longitudinal study in pregnant women, the alterations attributable to oxidative stress were present before the biochemical detection of the HbA1c increase. Usual recommendations once GD is detected (adequate metabolic control, as well as any other normally proposed to these patients) lowered the concentration of malondialdehyde at the end of pregnancy to the same levels of the healthy controls. Serum glutathione peroxidase activity in women with gestational diabetes increased during the gestational period.