Jeannette Davies, Ph.D.
Stroke causes ~144,000 deaths each year and is a leading cause of long-term adult disability in the US. Most strokes are caused when blood clots block blood vessels in the brain depriving neurons and support cells (called glia) of oxygen. Many neurons and glia will die, and those that survive often do not function properly. While drug treatment designed to dissolve the blood clot within a few hours of stroke can improve outcomes, less than 5% of stroke patients receive this treatment and many of those treated will still suffer from physical or mental disabilities. Therefore the development of therapies that can not only promote neuroprotection but also the formation of new neural circuits when delivered days or weeks after stroke, are of paramount importance.
Dr. Davies has recently initiated studies of stroke in my laboratory to test two complementary therapeutic approaches, a protein-based and a cell transplantation-based therapy, designed to promote recovery and repair after delayed administration in adult rodent models of stroke. Both approaches were originally developed as therapies for traumatic spinal cord injury in the laboratory of Dr. Stephen Davies, Associate Professor, Department of Neurosurgery. His group has shown that these therapies promote tissue repair and regeneration, plasticity, neuroprotection and restoration of function after traumatic spinal cord injury. Development of candidate cells for the transplantation-based therapies is also conducted in collaboration with Drs. Christophe Proschel, Margot Mayer-Proschel, and Mark Nobel at the University of Rochester Medical Center, Rochester, NY. I also continue to work with Dr. Davies on spinal cord injury studies, with the overall goal of translating promising therapies for stroke or spinal cord injury to clinical trial.
Judith Gault, Ph.D.
Dr. Gault collaborates with UC Denver neurosurgeons and pathologist Dr. DeMasters in investigating the genetics of stroke. Stroke is the 3rd leading cause of death in the United States and accounts for the largest portion of disability in people over the age of 60. Cerebral vascular malformations (CVMs) affect 3 million Americans, predisposing patients to a lifetime risk of hemorrhagic stroke and epilepsy. Cerebral cavernous malformation (CCM) lesions consist of dysmorphic blood filled caverns that are prone to repetitive hemorrhages and ongoing dysangiogenesis with proliferation of vascular endothelial cells to form new caverns. Familial CCM is genetically heterogeneous and families exhibit autosomal dominant Mendelian (single gene) inheritance at 3 known genes (CCM1, CCM2 and CCM3). However, within families there are clinically asymptomatic members and others with fatal disease. The CCM1, CCM2, and CCM3 genes have been identified contributing to approximately 40-54%, 13-38% and 4-6% of non-Hispanic familial cases, respectively. The majority of patients (80%) with CCM are apparently sporadic without a known family history of CCM. Single lesions are found in 75% of patients with sporadic CCM. The additional 25% of sporadic patients without a family history of disease have multiple CCMs and are thought to result from spontaneous new germline mutations or be unrecognized familial cases. Germline mutations have not been identified in sporadic CCM cases with single lesions; consistent with the hypothesis that these may result from somatic mutation(s) in the CCM genes. Our groupSomatic mutation detection in CCM lesions is technically challenging due to the fact that vascular endothelial cells that have been shown to harbor the somatic mutations comprise as little as 2.5%-10% of the cells of the lesions. Arteriovenous malformations (AVMs) of the brain and spinal cord are characterized by abnormal tangles of arteries and enlarged venous outflow channels (without an intervening capillary bed). Under high-flow conditions and arterialized pressure, AVMs are prone to catastrophic rupture. While the development of more definitive and safe treatment options for AVMs remains an issue of pressing clinical concern, basic understanding of the genetics in relation to pathobiology is an essential first step. CVM disease-causing genes have an essential, non-redundant function in angiogensis, establishing and maintaining the blood brain barrier in vascular endothelial cells. Therefore, CVM disease genes are important targets for cancer therapies.