Cellular Redox Imbalance and Neurochemical Effect in Cognitive-Deficient Old Rats

The purpose of the present study is to access the linkage between dysregulation of glutamatergic neurotransmission, oxidative metabolism, and serine signaling in age-related cognitive decline. In this work, we evaluated the effect of natural aging in rats on the cognitive abilities for hippocampal-dependent tasks. Oxidative metabolism indicators are glutathione (GSH), malondialdehyde (MDA) concentrations, and cytosolic phospholipase A2 (PLA2) activity. In addition, neurotransmitter amino acid (L-Glutamic acid, γ-aminobutyric acid (GABA), DL-Serine and DL-Aspartic acid) concentrations were studied in brain areas such as the frontal cortex (FC) and hippocampus (HPC). The spatial long-term memory revealed significant differences among experimental groups: the aged rats showed an increase in escape latency to the platform associated with a reduction of crossings and spent less time on the target quadrant than young rats. Glutathione levels decreased for analyzed brain areas linked with a significant increase in MDA concentrations and PLA2 activity in cognitive-deficient old rats. We found glutamate levels only increased in the HPC, whereas a reduced level of serine was found in both regions of interest in cognitive-deficient old rats. We demonstrated that age-related changes in redox metabolism contributed with alterations in synaptic signaling and cognitive impairment.

Long-Term Administration of Tianeptine in Depressed Patients after Alcohol Withdrawal

Alcohol interferes with the central metabolism of the catecholamines and especially with indolamines (5-HT). Thus, the use of an antidepressant such as tianeptine, whose main neurochemical effect is to increase the reuptake of 5-HT, seems to be particularly indicated for the continued treatment of depressed patients after alcohol withdrawal. This study evaluated the therapeutic efficacy and acceptability during long-term administration of tianeptine in depressed patients (major depressive episode or dysthymic disorder) in a multicentre trial, after withdrawal from alcohol abuse or dependence. The results relate to 130 depressed patients, who abstained from alcohol and received treatment for a year. Only one patient dropped-out because of side-effects, and medication was interrupted in 5% of subjects because of alcoholic relapses. Prescribed in the long term, tianeptine did not produce orthostatic hypotension, changes in bodyweight, or alterations in the ECG. All changes found in haematological and biochemical investigations suggested an improvement in patients' physical state. This, and other studies, indicate that tianeptine appears to have the potential to be a safe antidepressant, which might be particularly useful in those patients who are susceptible to the side-effects of psychotropic drugs.