Winter 2011 [pdf] - University of Kentucky - College of Pharmacy

Kim Nixon:
On the Cutting Edge of Alcoholism Research
A
tiny neuron, one-sixth the size of a grain of sand, found in the human
brain damaged from long-term alcohol abuse could potentially reverse
or ward off significant damage if pharmaceutical scientist Kim Nixon's
theories prove true. Nixon, assistant professor in the Department of
Pharmaceutical Sciences at the University of Kentucky's College of Pharmacy, is
currently focusing her research on alcoholic neuropathology in follow-up to the
discovery that neural stem cells produce two-fold more newborn neurons in the
adult brain after alcohol-induced damage.
It has been a long-held belief that alcohol abuse over a long
period of time destroys brain cells that were not completely
recoverable, even if the abuse stops.
"We've known for some time now that when an alcoholic
becomes abstinent, some brain mass recovers," Nixon said.
"What researchers in the field haven't considered is that new
neurons could be born and help in this recovery, which is the
focus of our work right now."
The belief that the number of nerve cells in the adult brain
are fixed early in life has given way to the theory that new
neurons are generated in adulthood through a process called
neurogenesis. The new cells originate from stem cells, which
Dr. Kim Nixon (center), with Dr. Jim Anderson, Director of the NIH Division of Program Coordination,
Planning, and Strategic Initiatives, and Dr. Kenneth Warren, Director of NIAAA at the NIH ceremonies.
6 Focus on Pharmacy
are cells that can divide indefinitely, renew themselves, and
give rise to a variety of cell types.
A major goal of Nixon's research is to identify and understand
the effect of alcohol on the environment surrounding the
stem cells, or “neurogenic niche” following binge-induced
brain damage. Secondarily, she hopes to identify factors
that influence the niche and how that endogenous pathway
may be harnessed for pharmacological treatment of alcoholinduced
neurodegeneration and/or alcoholism. Currently,
Nixon's lab has two National Institutes of Health (NIH) funded
projects that are investigating different aspects of alcohol and
neural stem cells.
If new neurons can be induced to form in the
alcohol-damaged brain, some regions could
be repopulated with healthy cells to stave
off significant impairment. Nixon's complex
research focuses on the interaction between
supporting cells of the nervous system, glia,
and the neural stem cells, which are able to
become a range of cells found in the nervous
system. The challenge is the structure and
function of the brain itself. Only two regions
of the brain can regenerate - the hippocampus
and the subventricular zone – but several
types of cells besides the supporting cells of
the nervous system and the neural stem cells
manufacture various brain chemicals and
growth factors. Trying to identify and describe
the functions of both types of cells and how
these functions interact and lead to the birth
of new neurons is another hurdle in Nixon's
work. The hippocampus is primarily involved in
learning and memory; the subventricular zone,
continued on page 18