Search results for "Neurotrophin"
showing 10 items of 83 documents
Intrinsically determined cell death of developing cortical interneurons.
2009
The cell death of inhibitory neurons, which originate far from the cortical areas to which they migrate during embryonic development, is determined autonomously rather than by competition for trophic signals from other cell types. It has long been known that apoptosis, a form of programmed cell death, eliminates young cells from developing tissues. In the field of neurobiology, it is widely believed that developmental neuronal-cell death results from cellular competition for environmentally derived survival signals that selects for an optimally sized and properly wired population of neurons. This study of developmental cell death in the mouse cortex in vivo, in vitro and after transplantati…
Proneurotrophin Binding to P75 Neurotrophin Receptor (P75ntr) Is Essential for Brain Lesion Formation and Functional Impairment after Experimental Tr…
2015
Traumatic brain injury (TBI) initiates an excessive mediator release of e.g. neurotrophins, which promote neuronal survival, differentiation, and modulate synaptic plasticity. Paradoxically, mature forms of neurotrophins promote neuronal survival, whereas unprocessed forms of neurotrophins induce cell death through p75 neurotrophin receptor (p75NTR) signaling. p75NTR is widely expressed during synaptogenesis and is subsequently downregulated in adulthood. Repair mechanisms after acute cerebral insults can reactivate its expression. Therefore, the influence of p75NTR on secondary brain damage was addressed. mRNA levels of p75NTR and its ligands were quantified in brain tissue up to 7 days af…
Retrograde neurotrophic signaling in rat retinal ganglion cells is transmitted via the ERK5 but not the ERK1/2 pathway.
2014
Purpose Neurotrophic deprivation is considered an important event in glaucomatous retinal ganglion cell (RGC) death. However, the mitogen-activated protein kinase (MAPK) pathway transmitting axonal neurotrophic signals in RGC has not been identified. We investigated the involvement of ERK5 and ERK1/2 in retrograde axonal neurotrophic signaling in rats. Methods Adult Sprague-Dawley rats were used. Retinal immunostaining for ERK5 and MEK5 was performed. Levels of total and phosphorylated ERK5 and ERK1/2 were analyzed in retinal lysate by quantitative Western blotting. The effects of age, brain-derived neurotrophic factor (BDNF) stimulation at RGC soma (intravitreal injection) or axon ending (…
Ipsilateral versus contralateral spontaneous post-stroke neuroplastic changes: involvement of BDNF?
2013
International audience; Stroke is a leading cause of death and disability in industrialized countries. Although surviving patients exhibit a certain degree of restoration of function attributable to brain plasticity, the majority of stroke survivors has to struggle with persisting deficits. In order to potentiate post-stroke recovery, several rehabilitation therapies have been undertaken and many experimental studies have reported that brain-derived neurotrophic factor (BDNF) is central to many facets of neuroplastic processes. However, although BDNF role in brain plasticity is well characterized through strategies that manipulate its content, the involvement of this neurotrophin in spontan…
''Circulating and Brain BDNF Levels in Stroke Rats. Relevance to Clinical Studies''
2011
International audience; ''Background: Whereas brain-derived neurotrophic factor (BDNF) levels are measured in the brain in animal models of stroke, neurotrophin levels in stroke patients are measured in plasma or serum samples. The present study was designed to investigate the meaning of circulating BDNF levels in stroke patients. Methods and Results: Unilateral ischemic stroke was induced in rats by the injection of various numbers of microspheres into the carotid circulation in order to mimic the different degrees of stroke severity observed in stroke patients. Blood was serially collected from the jugular vein before and after (4 h, 24 h and 8 d) embolization and the whole brains were co…
Mesenchymal Stem Cells Improve Motor Functions and Decrease Neurodegeneration in Ataxic Mice
2014
The main objective of this work is to demonstrate the feasibility of using bone marrow-derived stem cells in treating a neurodegenerative disorder such as Friedreich's ataxia. In this disease, the dorsal root ganglia of the spinal cord are the first to degenerate. Two groups of mice were injected intrathecally with mesenchymal stem cells isolated from either wild-type or Fxntm1Mkn/Tg(FXN)YG8Pook (YG8) mice. As a result, both groups presented improved motor skills compared to nontreated mice. Also, frataxin expression was increased in the dorsal root ganglia of the treated groups, along with lower expression of the apoptotic markers analyzed. Furthermore, the injected stem cells expressed th…
The impact of physical exercise on the circulating levels of BDNF and NT 4/5: A review
2021
(1) Background: One mechanism through which physical activity (PA) provides benefits is by triggering activity at a molecular level, where neurotrophins (NTs) are known to play an important role. However, the expression of the circulating levels of neurotrophic factors, brain-derived neurotrophic factor (BDNF) and neurotrophin-4 (NT-4/5), in response to exercise, is not fully understood. Therefore, the aim was to provide an updated overview on the neurotrophin (NT) variation levels of BDNF and NT-4/5 as a consequence of a long-term aerobic exercise intervention, and to understand and describe whether the upregulation of circulating NT levels is a result of neurotrophic factors produced and …
Lactate Threshold Training Program on Patients with Multiple Sclerosis: A Multidisciplinary Approach
2021
Physical activity could play a key role in improving the quality of life, particularly in patients with nervous system diseases such as multiple sclerosis (MS). Through lactacid anaerobic training, this study aims to investigate the effects at a bio-psycho-physical level to counteract the chronic fatigue associated with the pathology, and to improve mental health at a psychological and neurotrophic level. Eight subjects (age: 34.88 ± 4.45 years) affected by multiple sclerosis were involved. A lactate threshold training program was administered biweekly for 12 weeks at the beginning of the study (T0), at the end of the study (T1) and at 9 months after the end of the study (T2), with physical…
Changing fate
2020
Abstract The alpha-secretase A disintegrin and metalloproteinase 10 (ADAM10) and the beta-secretase beta-APP cleaving enzyme 1 (BACE-1) compete in neurons to cleave the amyloid precursor protein (APP). The reaction started by BACE-1, designated the amyloidogenic pathway, leads to formation of neurotoxic amyloid beta peptides (A-betas), while alpha-secretase prevents this and gives rise to an alternative cleavage product (APPs-alpha, nonamyloidogenic pathway). The latter is also known to have neurotrophic and neuroprotective properties. Therefore, identification of mechanisms that lead to a switch in APP processing from the amyloidogenic to the nonamyloidogenic pathway is an attractive avenu…
Updated overview on interplay between physical exercise, neurotrophins, and cognitive function in humans
2019
Highlights • Physical exercise maintains or improves cognitive functions, and neurotrophin receptor signaling may play an important role. • A positive relationship exists between physical exercise and circulating brain-derived neurotrophic factor levels. • Less clear evidence has been found for a relationship between physical exercise and other neurotrophin levels, such as nerve growth factor, neurotrophin-3, and neurotrophin-4. • The postexercise variation of brain-derived neurotrophic factor might be associated with improvement of neurocognitive functioning. • Physical exercise may be an inexpensive and safe strategy for boosting brain-derived neurotrophic factor release, thus preserving …