Alzheimer's disease (AD) and AD-related dementias (ADRD) are the common incurable
neurodegenerative
even
conditions characterized by progressive cognitive deterioration, memory decline and
death. The major forms of ADRD include vascular contributions to cognitive impairment and dementia
(VCID). In agreement, vascular dementia is the second most common form of dementia and the most
frequent comorbidity with AD. Diabetes
may
production
is a leading factor in the development of VCID; the ole of diabetes
primarily occur due to the abnormal glucose metabolism and i ncreased reactive oxygen species (ROS)
in cerebral vascular smooth muscle cells (CASMCs)
r
. In support, antioxidant therapies have
shown promising results in protecting against diabetes-induced VCID and other dementias.
the
molecular mechanisms that link diabetes to the development of VCID remain to be elucidated, and
current treatments for these diseases are neither always effective nor specific.
The
Based on our preliminary findings with previous work, in this project, we propose a novel central
hypothesis that diabetes increases Rieske iron-sulfur protein (RISP)-mediated mitochondrial ROS,
dissociates FK506 binding protein 12.6 (FKBP12.6) from type-2 ryanodine receptor (RyR2) to remove its
inhibitory effect on RyR2 channel and induce Ca2+ release, which causes cerebral vasoconstriction and
cerebral blood flow reduction, thereby leading to progressive memory loss, cognitive decline and VCID.
To test this exciting hypothesis, we will conduct a series of mechanistic studies primarily by employing
smooth muscle-specific RISP, RyR2, and FKBP12.6 knockout (KO) and/or overexpression (OE) mice with
other complementary advanced experimental approaches to address the following specific questions
(Specific Aims):
Aim 1: Are the increased RISP-mediated mitochondrial ROS in CASMCs essential for VCID induced by
diabetes?
Aim 2: Is RyR2/FKBP12.6 complex dissociation a key consequence for the increased RISP-mediated
mitochondrial ROS to mediate VCID induced by diabetes?
The objectives of the present proposal are not only to enhance our understanding of the molecular
mechanisms for VCID, ADRD
devastating diseases.
and
AD,
but also help to identify novel therapeutic targets for these common