Karen Coschigano
(Principal Investigator) has received a two-year,
$221,250 award from NIH for her R15 grant proposal
entitled “Cross-talk
between growth hormone and inflammation pathways in
kidney damage”.
Abstract of the
funded grant: Inflammation and the innate immune
system have long been known to play a major role in
many types of chronic kidney diseases. More
recently, their involvement has been extended to
include roles in diabetic nephropathy and even
damage due to aging. We have been studying kidney
damage in mouse models with different levels of
growth hormone (GH) signaling ranging from
over-expression to complete lack of GH signaling.
Mice with above normal levels of GH signaling
spontaneously develop kidney damage, progressing in
severity with increasing age. Mice with reduced or
no GH signaling are protected from damage, even when
diabetes is induced. We and others have observed
that levels of inflammatory markers are increased in
the kidneys of the mice with increased GH signaling,
indicating a positive correlation between GH
signaling and inflammation. Our overall goal is to
study the relationship between GH signaling and
inflammation in nephropathy. For this proposal we
wish to test two hypotheses: 1) Expression
of inflammatory markers will be reduced in kidneys
of diabetic mice with disrupted GH signaling, as
compared to expression in diabetic mice with intact
GH signaling; and 2) Direct induction of
inflammatory markers by cytokines will depend on an
intact GH signaling pathway in isolated glomeruli or
cell lines derived from isolated glomeruli (i.e.
mesangial cells and podocytes).
To test the first
hypothesis, we will induce diabetes in GHR/BP KO
mice, which lack GH signaling, and their NT
littermates, which have intact GH signaling, by
injection of streptozotocin, resulting in type 1
diabetes. After 10 weeks, we will measure both RNA
and protein levels of multiple inflammatory markers
within the kidneys. The changes in expression will
be correlated with changes in kidney morphology and
function as well as with GH signaling capability.
To test the second hypothesis, we will treat
glomeruli and cell lines (mesangial and podocyte),
isolated from NT and GHR/BP KO mice with mouse
recombinant TNF-alpha, a key mediator of
inflammation, and measure expression of cellular
inflammatory markers as described above, correlating
any changes in expression levels of inflammatory
markers with GH signaling capability. The
identification of cross-talk between GH signaling
and inflammation pathways will aid in the design of
specific, targeted approaches for the diagnosis,
treatment or prevention of diabetic kidney disease.
This project also provides many facets of learning
opportunities for undergraduate, graduate and
medical students working in the laboratory,
including underrepresented minorities. This
exposure to biomedical research will provide them
with a solid foundation upon which they can build a
career in the health-related fields.
Congratulations to
Karen!
For more
information, contact Karen Coschigano at
740-593-2196.