Maternal deprivation induces depressive-like behaviour and alters neurotrophin levels in the rat brain.

The present study was aimed to evaluate the behavioral and molecular effects of maternal deprivation in adult rats. To this aim, male rats deprived and non-deprived were assessed in the forced swimming and open-field tests in adult phase. In addition adrenocorticotrophin hormone (ACTH) levels was assessed in serum and brain-derived-neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and nerve growth factor (NGF) protein levels were assessed in prefrontal cortex, hippocampus and amygdala. We observed that maternal deprivation increased immobility time, and decreased climbing time, without affecting locomotor activity. ACTH circulating levels were increased in maternal deprived rats. Additionally, BDNF protein levels were reduced in the amygdala and NT-3 and NGF were reduced in both hippocampus and amygdala in maternal deprived rats, compared to control group. In conclusion, our results support the idea that behavioral, ACTH circulating levels and neurotrophins levels altered in maternal deprivation model could contribute to stress-related diseases, such as depression.

Reduction of hippocampal IL-6 levels in LPS-injected rats following acute exendin-4 treatment.

Preclinical evidence on the role of glucagon-like peptide-1 receptor (GLP-1r) agonists in the brain led to an increased interest in repurposing these compounds as a therapy for central nervous system (CNS) disorders and associated comorbidities. We aimed to investigate the neuroprotective effects of acute treatment with exendin (EX)-4, a GLP-1r agonist, in an animal model of inflammation. We evaluated the effect of different doses of EX-4 on inflammatory, neurotrophic, and oxidative stress parameters in the hippocampus and serum of lipopolysaccharide (LPS)-injected animals. Male Wistar rats were injected with LPS (0.25 mg/kg i.p.) and treated with different doses of EX-4 (0.1, 0.3, or 0.5 µg/kg i.p.). Sickness behavior was assessed by locomotor activity and body weight, and depressive-like behavior was also evaluated using forced swim test (FST). Brain-derived neurotrophic factor (BDNF), thiobarbituric acid reactive species (TBARS), and interleukin (IL)-6 were quantified in the serum and hippocampus. Glycemia was also analyzed pre- and post-EX-4 treatment. LPS groups exhibited decreased frequency of crossing and reduced body weight (p < 0.001), while alterations on FST were not observed. The higher dose of EX-4 reduced IL-6 in the hippocampus of LPS-injected animals (p = 0.018), and EX-4 per se reduced TBARS serum levels with a modest antioxidant effect in the LPS groups (p ≤ 0.005). BDNF hippocampal levels seemed to be increased in the LPS+EX-4 0.5 group compared with LPS+Saline (p > 0.05). Our study provides evidence on acute anti-inflammatory effects of EX-4 in the hippocampus of rats injected with LPS, contributing to future studies on repurposing compounds with potential neuroprotective properties.

Shortened telomere length in bipolar disorder: a comparison of the early and late stages of disease.

OBJECTIVE:: Bipolar disorder (BD) has been associated with increased rates of age-related diseases, such as type II diabetes, metabolic syndrome, osteoporosis, and cardiovascular disorders. Several biological findings have been associated with age-related disorders, including increased oxidative stress, inflammation, and telomere shortening. The objective of this study was to compare telomere length among participants with BD at early and late stages and age- and gender-matched healthy controls. METHODS:: Twenty-six euthymic subjects with BD and 34 healthy controls were recruited. Genomic DNA was extracted from peripheral blood and mean telomere length was measured using real-time quantitative polymerase chain reaction. RESULTS:: Telomere length was significantly shorter in both the early and late subgroups of BD subjects when compared to the respective controls (p = 0.002 and p = 0.005, respectively). The sample size prevented additional subgroup analyses, including potential effects of medication, smoking status, and lifestyle. CONCLUSION:: This study is concordant with previous evidence of telomere shortening in BD, in both early and late stages of the disorder, and supports the notion of accelerated aging in BD.

Olanzapine plus fluoxetine treatment increases Nt-3 protein levels in the rat prefrontal cortex.

Evidence is emerging for a role for neurotrophins in the treatment of mood disorders. In this study, we evaluated the effects of chronic administration of fluoxetine, olanzapine and the combination of fluoxetine/olanzapine on the brain-derived-neurotrophic factor (BDNF), nerve growth factor (NGF), and neurotrophin-3 (NT-3) in the rat brain. Wistar rats received daily injections of olanzapine (3 or 6 mg/kg) and/or fluoxetine (12.5 or 25mg/kg) for 28 days, and we evaluated for BDNF, NGF and NT-3 protein levels in the prefrontal cortex, hippocampus and amygdala. Our results showed that treatment with fluoxetine and olanzapine alone or in combination did not alter BDNF in the prefrontal cortex (p=0.37), hippocampus (p=0.98) and amygdala (p=0.57) or NGF protein levels in the prefrontal cortex (p=0.72), hippocampus (p=0.23) and amygdala (p=0.64), but NT-3 protein levels were increased by olanzapine 6 mg/kg/fluoxetine 25mg/kg combination in the prefrontal cortex (p=0.03), in the hippocampus (p=0.83) and amygdala (p=0.88) NT-3 protein levels did not alter. Finally, these findings further support the hypothesis that NT-3 could be involved in the effect of treatment with antipsychotic and antidepressant combination in mood disorders.

Shortened telomere length in bipolar disorder: a comparison of the early and late stages of disease

Objective: Bipolar disorder (BD) has been associated with increased rates of age-related diseases, such as type II diabetes, metabolic syndrome, osteoporosis, and cardiovascular disorders. Several biological findings have been associated with age-related disorders, including increased oxidative stress, inflammation, and telomere shortening. The objective of this study was to compare telomere length among participants with BD at early and late stages and age- and gender-matched healthy controls. Methods: Twenty-six euthymic subjects with BD and 34 healthy controls were recruited. Genomic DNA was extracted from peripheral blood and mean telomere length was measured using real-time quantitative polymerase chain reaction. Results: Telomere length was significantly shorter in both the early and late subgroups of BD subjects when compared to the respective controls (p = 0.002 and p = 0.005, respectively). The sample size prevented additional subgroup analyses, including potential effects of medication, smoking status, and lifestyle. Conclusion: This study is concordant with previous evidence of telomere shortening in BD, in both early and late stages of the disorder, and supports the notion of accelerated aging in BD.