Long-term administration of soft drink causes memory impairment and oxidative damage in adult and middle-aged rats.

Introduction: The consumption of soft drinks has increased considerably in recent decades, mainly cola soft drinks. Excessive consumption of cola-based soft drinks is associated with several diseases and cognitive decline, particularly memory impairment. Furthermore, diets with high sugar can promote insulin resistance, metabolic syndrome, and dyslipidemia.

The impact of chronic mild stress on long-term depressive behavior in rats which have survived sepsis.

The present study was created to investigate the effects of chronic mild stress (CMS) on the depressive behavior and neurochemical parameters of rats that were subjected to sepsis. Wistar rats were subjected to a CMS protocol, and sepsis was induced by cecal ligation and perforation (CLP). The animals were then divided into 4 separate groups; Control + Sham (n = 20), Control + CLP (n = 30), CMS + Sham (n = 20) and CMS + CLP (n = 30).

Anxious phenotypes plus environmental stressors are related to brain DNA damage and changes in NMDA receptor subunits and glutamate uptake.

This study aimed at investigating the effects of chronic mild stress on DNA damage, NMDA receptor subunits and glutamate transport levels in the brains of rats with an anxious phenotype, which were selected to represent both the high-freezing (CHF) and low-freezing (CLF) lines. The anxious phenotype induced DNA damage in the hippocampus, amygdala and nucleus accumbens (NAc). CHF rats subjected to chronic stress presented a more pronounced DNA damage in the hippocampus and NAc.

Ketamine treatment partly reverses alterations in brain derived- neurotrophic factor, oxidative stress and energy metabolism parameters induced by an animal model of depression.

Studies have suggested that ketamine, a nonselective NMDA receptor antagonist, could be a new drug in the treatment of major depression, but the way ketamine presents such effects remains to be elucidated. Therefore, the objective of this paper was to evaluate the effects of ketamine treatment on parameters related to depression in the brain of adult rats subjected to an animal model of depression. The animals were divided into: non-deprived + saline; non-deprived + ketamine; deprived + saline; deprived + ketamine.

Ketamine ameliorates depressive-like behaviors and immune alterations in adult rats following maternal deprivation.

A growing body of evidence points toward an association between the glutamatergic system, as well as immune system dysregulation and major depression. So, the present study was aimed at evaluating the behavioral and molecular effects of the ketamine, an antagonist of the N-methyl-D-aspartate (NMDA) receptor of glutamate in maternally deprived adult rats. In deprived rats treated with saline, we observed an increase in the immobility time; however, ketamine treatment reversed this effect, decreasing immobility time.

MAPK signaling correlates with the antidepressant effects of ketamine.

Studies have pointed to a relationship between MAPK kinase (MEK) signaling and the behavioral effects of antidepressant drugs. So, in the present study we examined the behavioral and molecular effects of ketamine, an antagonist of the N-methyl-d-aspartate receptor (NMDA), which has been shown to have an antidepressant effect after the inhibition of MEK signaling in Wistar rats. Our results showed that acute administration of the MEK inhibitor PD184161, produced depressive-like behavior and stopped antidepressant-like effects of ketamine in the forced swimming test.

Ketamine and imipramine in the nucleus accumbens regulate histone deacetylation induced by maternal deprivation and are critical for associated behaviors.

Studies indicate that histone deacetylation is important for long term changes related to stress and antidepressant treatment. The present study aimed to evaluate the effects of the classic antidepressant imipramine, and of an antagonist of the N-methyl-d-asparte (NMDA) receptor, ketamine, on behavior and histone deacetylase (HDAC) activity in the brains of maternally deprived adult rats. To this aim, deprived and non-deprived (control) male Wistar rats were divided into the following groups: non-deprived+saline; non-deprived+imipramine (30 mg/kg); non-deprived+ketamine (15 mg/kg); deprived+saline; deprived+imipramine (30 mg/kg); and deprived+ketamine (15 mg/kg).

Treatment with tianeptine induces antidepressive-like effects and alters the neurotrophin levels, mitochondrial respiratory chain and cycle Krebs enzymes in the brain of maternally deprived adult rats.

Maternally deprived rats were treated with tianeptine (15 mg/kg) once a day for 14 days during their adult phase. Their behavior was then assessed using the forced swimming and open field tests. The BDNF, NGF and energy metabolism were assessed in the rat brain.