Stem cell therapy

[Swarfmaker]

Watching Stem Cells Repair The Human Brain
ScienceDaily (Aug. 19, 2009) — There is no known cure for
neurodegenerative diseases such as Huntington's, Alzheimer's and
Parkinson's. But new hope, in the form of stem cells created from the
patient's own bone marrow, can be found — and literally seen — in
laboratories at Tel Aviv University.

This study is based on differentiated mesenchymal cells (MSC), which
were discovered at Tel Aviv University. Bone marrow cells are
transformed into NTFs-secreting stem cells, which can then be used to
treat neurodegenerative diseases. This advance circumvents the ethical
debate caused by the use of stem cells obtained from embryos.

Although there is a drawback to using this particular type of stem
cell — the higher degree of difficulty involved in rendering them
"neuron-like" — the benefits are numerous. "Bone marrow-derived MSCs
bypass ethical and production complications," says Dr. Cohen, "and in
the long run, the cells are less likely to be rejected because they
come from the patients themselves. This means you don't need
immunosuppressant therapy."
http://www.sciencedaily.com/releases/2009/08/090819153931.htm

How The Pathology Of Parkinson's Disease Spreads
ScienceDaily (July 29, 2009) — Accumulation of the synaptic protein
alpha-synuclein, resulting in the formation of aggregates called Lewy
bodies in the brain, is a hallmark of Parkinson's and other related
neurodegenerative diseases. This pathology appears to spread
throughout the brain as the disease progresses. Now, researchers at
the University of California, San Diego School of Medicine and Konkuk
University in Seoul, South Korea, have described how this mechanism
works.

Their findings – the first to show neuron-to-neuron transmission of
alpha-synuclein – will appear in the Proceedings of the National
Academy of Sciences (PNAS) on July 29.

"The discovery of cell-to-cell transmission of this protein may
explain how alpha-synuclein aggregates can pass to new, healthy
cells," said first author Paula Desplats, project scientist in UC San
Diego's Department of Neurosciences. "We demonstrated how alpha-
synuclein is taken up by neighboring cells, including grafted neuronal
precursor cells, a mechanism that may cause Lewy bodies to spread to
different brain structures."

"Our findings indicate that the stem cells used to replace lost or
damaged cells in the brains of Parkinson's disease patients are also
susceptible to degeneration,"

In a large proportion of Parkinson's disease cases, the aggregation of
alpha-synuclein progresses in a predictable pattern – from the lower
brainstem, into the limbic system and eventually to the neocortex, the
part of the brain responsible for higher level cognitive functions.
The hypothesis of disease progression by neuron-to-neuron transmission
of alpha-synuclein that encouraged this study was supported by
findings of two separate reports in 2008. In these studies, autopsies
of deceased Parkinson's patients who had received implants of
therapeutic fetal neurons 11 to 16 years prior revealed that alpha-
synuclein had propagated to the transplanted neurons.

Next, the team tested to determine if alpha-synuclein could be
transmitted directly from host to grafted cells in a mouse model of
Parkinson's disease. Brains of the mouse model were grafted with
fresh, healthy stem cells. Within four weeks, cells containing Lewy
body-like masses were quite common, supporting the cell-to cell
transmission mechanism.
http://www.sciencedaily.com/releases/2009/07/090727191914.htm