SILAHKAN MENGGUNAKAN " MESIN TRANSLATE "..GOOGLE TRANSLATE
DISAMPING KANAN INI.............
PLEASE USE ........ "TRANSLATE MACHINE" .. GOOGLE TRANSLATE BESIDE RIGHT THIS
....................................
DISAMPING KANAN INI.............
PLEASE USE ........ "TRANSLATE MACHINE" .. GOOGLE TRANSLATE BESIDE RIGHT THIS
....................................
Transplantasi
dari sel-sel otak yang baru membalikkan kehilangan memori dalam model penyakit
Alzheimer
Transplantation of new brain cells reverses memory loss in Alzheimer's
disease model
Date:
July 15,
2014
Source:
Gladstone Institutes
Summary:
A new study has revealed a way to alleviate the
learning and memory deficits caused by apoE4, the most important genetic risk
factor for Alzheimer's disease, improving cognition to normal levels in aged
mice. The success of the treatment in older mice, which corresponded to late
adulthood in humans, is particularly important, as this would be the age that
would be targeted were this method ever to be used therapeutically in people.
..................
A new study from the Gladstone Institutes has revealed a way
to alleviate the learning and memory deficits caused by apoE4, the most
important genetic risk factor for Alzheimer's disease, improving cognition to
normal levels in aged mice.
In the
study, which was conducted in collaboration with researchers at UC San
Francisco and published today in the Journal of Neuroscience, scientists
transplanted inhibitory neuron progenitors -- early-stage brain cells that have
the capacity to develop into mature inhibitory neurons -- into two mouse models
of Alzheimer's disease, apoE4 or apoE4 with accumulation of amyloid beta,
another major contributor to Alzheimer's. The transplants helped to replenish
the brain by replacing cells lost due to apoE4, regulating brain activity and
improving learning and memory abilities.
"This
is the first time transplantation of inhibitory neuron progenitors has been
used in aged Alzheimer's disease models," said first author Leslie Tong, a
graduate student at the Gladstone Institutes and UCSF. "Working with older
animals can be challenging from a technical standpoint, and it was amazing to
see that the cells not only survived but affected activity and behavior."
The success
of the treatment in older mice, which corresponded to late adulthood in humans,
is particularly important, as this would be the age that would be targeted were
this method ever to be used therapeutically in people.
"This
is a very important proof of concept study," said senior author Yadong
Huang, MD, PhD, an associate investigator at Gladstone Institutes and associate
professor of neurology and pathology at UCSF. "The fact that we see a
functional integration of these cells into the hippocampal circuitry and a
complete rescue of learning and memory deficits in an aged model of Alzheimer's
disease is very exciting."
A balance of
excitatory and inhibitory activity in the brain is essential for normal
function. However, in the apoE4 model of Alzheimer's disease -- a genetic risk
factor that is carried by approximately 25% of the population and is involved
in 60-75% of all Alzheimer's cases -- this balance gets disrupted due to a
decline in inhibitory regulator cells that are essential in maintaining normal
brain activity. The hippocampus, an important memory center in the brain, is
particularly affected by this loss of inhibitory neurons, resulting in an
increase in network activation that is thought to contribute to the learning
and memory deficits characteristic of Alzheimer's disease. The accumulation of
amyloid beta in the brain has also been linked to this imbalance between
excitatory and inhibitory activity in the brain.
In the
current study, the researchers hoped that by grafting inhibitory neuron
progenitors into the hippocampus of aged apoE4 mice, they would be able to
combat these effects, replacing the lost cells and restoring normal function to
the area. Remarkably, these new inhibitory neurons survived in the hippocampus,
enhancing inhibitory signaling and rescuing impairments in learning and memory.
In addition,
when these inhibitory progenitor cells were transplanted into apoE4 mice with
an accumulation of amyloid beta, prior deficits were alleviated. However, the
new inhibitory neurons did not affect amyloid beta levels, suggesting that the
cognitive enhancement did not occur as a result of amyloid clearance, and
amyloid did not impair the integration of the transplant.
According to
Dr. Huang, the potential implications for these findings extend beyond the
current methods used. "Stem cell therapy in humans is still a long way
off. However, this study tells us that if there is any way we can enhance
inhibitory neuron function in the hippocampus, like through the development of
small molecule compounds, it may be beneficial for Alzheimer disease
patients."
Story
Source:
The above
story is based on materials provided by Gladstone Institutes. Note: Materials may be edited
for content and length.
Journal
Reference:
- L. M. Tong, B. Djukic, C. Arnold, A. K. Gillespie, S. Y. Yoon, M. M. Wang, O. Zhang, J. Knoferle, J. L. R. Rubenstein, A. Alvarez-Buylla, Y. Huang. Inhibitory Interneuron Progenitor Transplantation Restores Normal Learning and Memory in ApoE4 Knock-In Mice without or with A Accumulation. Journal of Neuroscience, 2014; 34 (29): 9506 DOI: 10.1523/JNEUROSCI.0693-14.2014