50 research outputs found
A neuroligin-3 mutation implicated in autism causes abnormal aggression and increases repetitive behavior in mice
Moderate exercise and chronic stress produce counteractive effects on different areas of the brain by acting through various neurotransmitter receptor subtypes: A hypothesis
BACKGROUND: Regular, "moderate", physical exercise is an established non-pharmacological form of treatment for depressive disorders. Brain lateralization has a significant role in the progress of depression. External stimuli such as various stressors or exercise influence the higher functions of the brain (cognition and affect). These effects often do not follow a linear course. Therefore, nonlinear dynamics seem best suited for modeling many of the phenomena, and putative global pathways in the brain, attributable to such external influences. HYPOTHESIS: The general hypothesis presented here considers only the nonlinear aspects of the effects produced by "moderate" exercise and "chronic" stressors, but does not preclude the possibility of linear responses. In reality, both linear and nonlinear mechanisms may be involved in the final outcomes. The well-known neurotransmitters serotonin (5-HT), dopamine (D) and norepinephrine (NE) all have various receptor subtypes. The article hypothesizes that 'Stress' increases the activity/concentration of some particular subtypes of receptors (designated nt(s)) for each of the known (and unknown) neurotransmitters in the right anterior (RA) and left posterior (LP) regions (cortical and subcortical) of the brain, and has the converse effects on a different set of receptor subtypes (designated nt(h)). In contrast, 'Exercise' increases nt(h )activity/concentration and/or reduces nt(s )activity/concentration in the LA and RP areas of the brain. These effects may be initiated by the activation of Brain Derived Neurotrophic Factor (BDNF) (among others) in exercise and its suppression in stress. CONCLUSION: On the basis of this hypothesis, a better understanding of brain neurodynamics might be achieved by considering the oscillations caused by single neurotransmitters acting on their different receptor subtypes, and the temporal pattern of recruitment of these subtypes. Further, appropriately designed and planned experiments will not only corroborate such theoretical models, but also shed more light on the underlying brain dynamics
Sexually Dimorphic Serotonergic Dysfunction in a Mouse Model of Huntington's Disease and Depression
Depression is the most common psychiatric disorder in Huntington's disease (HD) patients. In the general population, women are more prone to develop depression and such susceptibility might be related to serotonergic dysregulation. There is yet to be a study of sexual dimorphism in the development and presentation of depression in HD patients. We investigated whether 8-week-old male and female R6/1 transgenic HD mice display depressive-like endophenotypes associated with serotonergic impairments. We also studied the behavioral effects of acute treatment with sertraline. We found that only female HD mice exhibited a decreased preference for saccharin as well as impaired emotionality-related behaviors when assessed on the novelty-suppressed feeding test (NSFT) and the forced-swimming test (FST). The exaggerated immobility time displayed by female HD in the FST was reduced by acute administration of sertraline. We also report an increased response to the 5-HT1A receptor agonist 8-OH-DPAT in inducing hypothermia and a decreased 5-HT2A receptor function in HD animals. While tissue levels of serotonin were reduced in both male and female HD mice, we found that serotonin concentration and hydroxylase-2 (TPH2) mRNA levels were higher in the hippocampus of males compared to female animals. Finally, the antidepressant-like effects of sertraline in the FST were blunted in male HD animals. This study reveals sex-specific depressive-related behaviors during an early stage of HD prior to any cognitive and motor deficits. Our data suggest a crucial role for disrupted serotonin signaling in mediating the sexually dimorphic depression-like phenotype in HD mice
VGLUT2 controls heat and punctuate hyperalgesia associated with nerve injury via TRPV1-Cre primary afferents
Correlation of clinico-pathologic data with inflammatory cells infiltration in colorectal cancer
Introduction: Colorectal cancer (CRC) is the third most common cancer worldwide. At every phase of cancer development, the inflammatory process has an important impact. Accurate assessment inflammatory cells in the tumour environment in conjunction with clinico-pathologic features can be a relevant prognostic or predictive parameter. Purpose: To analyse inflammatory cell infiltration in CRC tumour mass and correlate with chosen clinico-pathologic parameters. Materials and methods: The study group consisted of 160 patients (64 women, 96 men) diagnosed with colorectal cancer who underwent surgery. Tissue material obtained from routine histopathological diagnosis was stained with H&E and used to assess the type of inflammatory cells in the invasive front and centre of the tumour. Results were subjected to statistical analysis with the age and gender of patients, tumour localization, tumour growth and size, TNM stage, adenocarcinoma type, fibrosis, necrosis, metastasis and tumour invasion (by the Spearman’s correlation coefficient test). Results: The presence of neutrophils in the invasive front of tumour mass was associated with fibrosis and inflammatory cell infiltration in the invasive front of tumour. Macrophages in the invasive front of tumour were found to correlate with tumour growth (expanding and infiltrate). Macrophages and eosinophils were associated with inflammatory cell infiltration in the invasive front and in the centre of tumour. Conclusions: The type of inflammatory cells in the invasive front or centre of the tumour may be useful to prognoses clinical features of colorectal cance