It amazes me that we are having such a hard time getting the backing for the
NIDS trials. Everything keeps pointing toward this as being the answer for
our kids. When you look at the markers found in kids that later developed
autism, it seems to be one more piece that validates the NIDS hypothosis.
So where is the $$$,
"The findings, reported Wednesday at a San Diego meeting of the American
Academy of Neurology, suggest that autism probably arises from a combination
of genetic defects and exposure to toxic chemicals, viruses or other
environmental substances. It also indicates that the crucial period for such
factors is during the early weeks of pregnancy, when the central nervous
system is forming."
"Nelson reported Wednesday at the meeting that four of the
proteins--vasoactive intestinal peptide, calcitonin-related gene peptide,
brain-derived neurotrophic factor and neurotrophin 4--were present at
elevated levels in 96.9% of the autistic children and 92.4% of those with
mental retardation. In contrast, they were elevated in only 9.2% of the
children with cerebral palsy and in none of the healthy control subjects."
If we look at what these actually are and what they do, it seems insane
that nothing is being done, NOW. There is so much science that validates
the mechanisms involved and how other things like infections/immune
stressors can cause the deterioration and worsening of the neuroimmune
dysfunction. Yet so many want to try to focus on one trigger as being the
cause. I can understand why Dr. G gets so frustrated at the different
things going on.
Cheryl
"Activated brain microglia play a pivotal role in inflammatory and
degenerative disorders, mediating immune function and producing toxic and
trophic agents. We previously reported that microglia express neurotrophins"
Cutting edge: clonally restricted production of the neurotrophins
brain-derived neurotrophic factor and neurotrophin-3 mRNA by human immune
cells and Th1/Th2-polarized expression of their receptors.
Author
Besser M; Wank R
Address
Institute of Immunology, University of Munich, Munich, Germany.
Source
J Immunol, 1999 Jun, 162:11, 6303-6
Abstract
Neurotrophins, such as neurotrophin-3 (NT-3) and brain-derived neurotrophic
factor (BDNF), are potent regulators of neuronal functions. Here we show
that human immune cells also produce NT-3 mRNA, secrete BDNF, and express
their specific receptors trkB and trkC. The truncated trkB receptor, usually
expressed in sensory neurons of the central nervous system, was also
constitutively expressed in unstimulated Th cells. Full-length trkB was
detectable in stimulated PBMC, B cell lines, and Th1, but not in Th2 and Th0
cell clones. Clonally restricted expression was also observed for trkC,
until now not detected on blood cells. The Th1 cytokine IL-2 stimulated
production of trkB mRNA but not of trkC, whereas the Th2 cytokine IL-4
enhanced NT-3 but not BDNF mRNA expression. Microbial Ags, which influence
the Th1/Th2 balance, could therefore modulate the neurotrophic system and
thereby affect neuronal synaptic activity of the central nervous system.
Language of Publication
English
Unique Identifier
99282907
Learning abilities, NGF and BDNF brain levels in two lines of TNF-alpha
transgenic mice, one characterized by neurological disorders, the other
phenotypically normal.
Author
Aloe L; Properzi F; Probert L; Akassoglou K; Kassiotis G; Micera A; Fiore M
Address
Institute of Neurobiology, CNR, viale Marx, 43-15, 00137, Rome, Italy.
aloe@...
Source
Brain Res, 1999 Sep, 840:1-2, 125-37
Abstract
In this study we used two lines of transgenic mice overexpressing tumor
necrosis factor alpha (TNF-alpha) in the central nervous system (CNS), one
characterized by reactive gliosis, inflammatory demyelination and
neurological deficits (Tg6074) the other showing no neurological or
phenotypical alterations (TgK3) to investigate the effect of TNF-alpha on
brain nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF)
levels and learning abilities. The results showed that the amount of NGF in
the brain of Tg6074 and TgK3 transgenic mice is low in the hippocampus and
in the spinal cord, increases in the hypothalamus of Tg6074 and showed no
significant changes in the cortex. BDNF levels were low in the hippocampus
and spinal cord of TgK3. BDNF increased in the hypothalamus of TgK3 and
Tg6074 while in the cortex, BDNF increased only in Tg6074 mice. Transgenic
mice also had memory impairments as revealed by the Morris Water Maze test.
These findings indicate that TNF-alpha significantly influences BDNF and NGF
synthesis, most probably in a dose-dependent manner. Learning abilities were
also differently affected by overexpression of TNF-alpha, but were not
associated with inflammatory activity. The possible functional implications
of our findings are discussed.
Language of Publication
English
Unique Identifier
99448140
BDNF gene transfer to the mammalian brain using CNS-derived neural
precursors.
Author
Rubio F; Kokaia Z; Arco A; García Simón M; Snyder E; Lindvall O; Satrústegui
J; Martínez Serrano A
Address
Center of Molecular Biology Severo Ochoa, Autonomous University of Madrid,
CSIC, Madrid, Spain.
Source
Gene Ther, 1999 Nov, 6:11, 1851-66
Abstract
Neural stem cell lines represent a homogeneous source of cells for genetic,
developmental, and gene transfer and repair studies in the nervous system.
Since both gene transfer of neurotrophic factors and cell replacement
strategies are of immediate interest for therapeutical purposes, we have
generated BDNF-secreting neural stem cell lines and investigated to what
extent different endogenous levels of BDNF expression affect in vitro
survival, proliferation and differentiation of these cells. Also, we have
investigated the in vivo effects of such BDNF gene transfer procedure in the
rat neostriatum. Hippocampus- and cerebellum-derived cell lines reacted
differently to manipulations aimed at varying their levels of BDNF
production. Over-expression of BDNF enhanced survival of both cell types, in
a serum-deprivation assay. Conversely, and ruling out unspecific effects,
expression of an antisense version of BDNF resulted in compromised survival
of cerebellum-derived cells, and in a lethal phenotype in hippocampal
progenitors. These data indicate that endogenous BDNF level strongly
influences the in vitro survival of these cells. These effects are more
pronounced for hippocampus- than for cerebellum-derived progenitors.
Hippocampus-derived BDNF overproducers showed no major change in their
capacity to differentiate towards a neuronal phenotype in vitro. In
contrast, cerebellar progenitors overproducing BDNF did not differentiate
into neurons, whereas cells expressing the antisense BDNF construct
generated cells with morphological features of neurons and expressing
immunological neuronal markers. Taken together, these results provide
evidence that BDNF controls both the in vitro survival and differentiation
of neural stem cells. After in vivo transplantation of BDNF-overproducing
cells to the rat neostriatum, these survived better than the control ones,
and induced the expected neurotrophic effects on cholinergic neurons.
However, long-term (3 months) administration of BDNF resulted in detrimental
effects, at this location. These findings may be of importance for the
understanding of brain development, for the design of therapeutic
neuro-regenerative strategies, and for cell replacement and gene therapy
studies.
Language of Publication
English
Unique Identifier
20070364