Evidences for Mutant Huntingtin Inducing Musculoskeletal and Brain Growth Impairments via Disturbing Testosterone Biosynthesis in Male Huntington Disease Animals.

Body weight (BW) loss and reduced body mass index (BMI) are the most common peripheral alterations in Huntington disease (HD) and have been found in HD mutation carriers and HD animal models before the manifestation of neurological symptoms. This suggests that, at least in the early disease stage, these changes could be due to abnormal tissue growth rather than tissue atrophy. Moreover, BW and BMI are reported to be more affected in males than females in HD animal models and patients.

Environmental stimulation in Huntington disease patients and animal models.

While Huntington disease (HD) is caused solely by a polyglutamine expansion in the huntingtin gene, environmental factors can influence HD onset and progression. Here, we review studies linking environment and HD in both humans and animal models. In HD patients, we find that: (i) an active lifestyle associates with both a delayed age at onset of HD and a decreased severity of symptoms, (ii) applying physical exercise and behavioral therapies in small cohorts of HD subjects indicate promising effects on the HD symptomatology, (iii) Mediterranean diet correlates with lower motor impairment, and treatments based on omega-3 fatty acids improve motor function , whereas (iv) increased cortisol levels associate with specific HD symptoms.

Validation of behavioral phenotypes in the BACHD rat model.

Huntington disease (HD) is a neurodegenerative disorder caused by a polyglutamine expansion in the HTT gene. Various HD animal models have been generated to mimic the motor, cognitive and neuropsychiatric disturbances that affect HD patients. Reproducing disease phenotypes within these models is essential to identify reliable readouts for therapy studies.

Intranasal Administration of Mesenchymal Stem Cells Ameliorates the Abnormal Dopamine Transmission System and Inflammatory Reaction in the R6/2 Mouse Model of Huntington Disease.

Intrastriatal administration of mesenchymal stem cells (MSCs) has shown beneficial effects in rodent models of Huntington disease (HD). However, the invasive nature of surgical procedure and its potential to trigger the host immune response may limit its clinical use. Hence, we sought to evaluate the non-invasive intranasal administration (INA) of MSC delivery as an effective alternative route in HD.

The BACHD rat model of Huntington disease shows slowed learning in a Go/No-Go-like test of visual discrimination.

Huntington disease is a hereditary neurodegenerative disease, in which patients display a broad range of clinical symptoms. Among these, impaired inhibitory control has been noted. The BACHD rat is a recently developed and established transgenic animal model for Huntington disease, and characterizing the presence of Huntington disease-like behavioural phenotypes in these animals is of importance.

Sexual behavior and testis morphology in the BACHD rat model.

Background: Huntington disease (HD) is an autosomal dominant neurodegenerative disorder caused by a mutation in the huntingtin (HTT) gene, which results in brain neurodegeneration and peripheral pathology affecting different organs including testis. Patients with HD suffer from motor and cognitive impairment, and multiple psychiatric symptoms. Among behavioral abnormalities in HD, sexual disturbances have often been reported, but scarcely investigated in animal models.

Environment-dependent striatal gene expression in the BACHD rat model for Huntington disease.

Huntington disease (HD) is an autosomal dominant neurodegenerative disorder caused by a mutation in the huntingtin (HTT) gene which results in progressive neurodegeneration in the striatum, cortex, and eventually most brain areas. Despite being a monogenic disorder, environmental factors influence HD characteristics. Both human and mouse studies suggest that mutant HTT (mHTT) leads to gene expression changes that harbor potential to be modulated by the environment.

BACHD rats expressing full-length mutant huntingtin exhibit differences in social behavior compared to wild-type littermates.

Background: Huntington disease (HD) is a devastating inherited neurodegenerative disorder characterized by progressive motor, cognitive, and psychiatric symptoms without any cure to slow down or stop the progress of the disease. The BACHD rat model for HD carrying the human full-length mutant huntingtin protein (mHTT) with 97 polyQ repeats has been recently established as a promising model which reproduces several HD-like features. While motor and cognitive functions have been characterized in BACHD rats, little is known about their social phenotype.

Structural and molecular myelination deficits occur prior to neuronal loss in the YAC128 and BACHD models of Huntington disease.

White matter (WM) atrophy is a significant feature of Huntington disease (HD), although its aetiology and early pathological manifestations remain poorly defined. In this study, we aimed to characterize WM-related features in the transgenic YAC128 and BACHD models of HD. Using diffusion tensor magnetic resonance imaging (DT-MRI), we demonstrate that microstructural WM abnormalities occur from an early age in YAC128 mice.

Despite higher glucocorticoid levels and stress responses in female rats, both sexes exhibit similar stress-induced changes in hippocampal neurogenesis.

Sex differences in stress reactivity may be one of the factors underlying the increased sensitivity for the development of psychopathologies in women. Particularly, an increased hypothalamic-pituitary-adrenal (HPA) axis reactivity in females may exacerbate stress-induced changes in neuronal plasticity and neurogenesis, which in turn may contribute to an increased sensitivity to psychopathology. The main aim of the present study was to examine male-female differences in stress-induced changes in different aspects of hippocampal neurogenesis, i.

Chronic partial sleep deprivation reduces brain sensitivity to glutamate N-methyl-D-aspartate receptor-mediated neurotoxicity.

It has been hypothesized that insufficient sleep may compromise neuronal function and contribute to neurodegenerative processes. While sleep loss by itself may not lead to cell death directly, it may affect the sensitivity to a subsequent neurodegenerative insult. Here we examined the effects of chronic sleep restriction (SR) on the vulnerability of the brain to N-methyl-d-aspartate (NMDA)-induced excitotoxicity.

Coping with sleep deprivation: shifts in regional brain activity and learning strategy.

Study Objectives: dissociable cognitive strategies are used for place navigation. Spatial strategies rely on the hippocampus, an area important for flexible integration of novel information. Response strategies are more rigid and involve the dorsal striatum.

Maternal separation decreases adult hippocampal cell proliferation and impairs cognitive performance but has little effect on stress sensitivity and anxiety in adult Wistar rats.

Stressful events during childhood are thought to increase the risk for the development of adult psychopathology. A widely used animal model for early life stress is maternal separation (MS), which is thought to affect development and cause alterations in neuroendocrine stress reactivity and emotionality lasting into adulthood. However, results obtained with this paradigm are inconsistent.

Sleep deprivation impairs spatial working memory and reduces hippocampal AMPA receptor phosphorylation.

Sleep is important for brain function and cognitive performance. Sleep deprivation (SD) may affect subsequent learning capacity and ability to form new memories, particularly in the case of hippocampus-dependent tasks. In the present study we examined whether SD for 6 or 12 h during the normal resting phase prior to learning affects hippocampus-dependent working memory in mice.

Chronically restricted sleep leads to depression-like changes in neurotransmitter receptor sensitivity and neuroendocrine stress reactivity in rats.

Study Objectives: Frequently disrupted and restricted sleep is a common problem for many people in our Western society. In the long run, insufficient sleep may have repercussions for health and may sensitize individuals to psychiatric diseases. In this context, we applied an animal model of chronic sleep restriction to study effects of sleep loss on neurobiological and neuroendocrine systems that have been implied in the pathophysiology of depression, particularly the serotonergic system and the hypothalamic-pituitary-adrenal (HPA) axis.