Marilyn J Cipolla
University Of Vermont & St Agric College
Project start date: 2003-04-01
Project end date: 2014-01-31
Sponsored Links Excellgen http://Excellgen.com
CEREBROVASCULAR CHANGES IN PREGNANCY AND HYPERTENSION
Marilyn J Cipolla, Associate Professor
University Of Vermont & St Agric College, 85 South Prospect Street, Burlington, Vt 05405
Grant 5R01NS045940-06 from National Institute Of Neurological Disorders And Stroke
Abstract: Eclampsia is a serious complication of pregnancy that occurs when hypertension during pregnancy develops with neurologic complications, including headache, vomiting, blindness and convulsions. While multiple organs are affected by hypertension in pregnancy, cerebrovascular involvement is the direct cause of death in ~40% of patients. The major cerebrovascular changes that occur during eclampsia are thought to be similar to hypertensive encephalopathy in which acute elevations in pressure cause autoregulatory breakthrough, hyperperfusion and edema. Our preliminary studies found that late-pregnant animals had significantly decreased cerebrovascular resistance and hyperperfusion compared to nonpregnant animals during acute hypertension, similar to eclampsia. Importantly, only the late-pregnant animals developed cerebral edema, suggesting that pregnancy alone predisposes the brain to the neurologic complications of eclampsia when blood pressure is elevated. Because of the prominent role of edema formation in mediating the neurologic complications of eclampsia, the long-term objective of this project is understand the underlying mechanisms by which pregnancy and hypertension in pregnancy affect the cerebral circulation in a way that promotes hydrostatic brain edema during increased blood pressure. Our preliminary studies suggest for the first time that pregnancy causes outward remodeling of cerebral arterioles, an effect that likely diminishes small vessel resistance in the brain during acute hypertension. Aim 1 will therefore investigate underlying mechanisms by which pregnancy causes outward remodeling, including the hormone relaxin, known to promote vascular remodeling in the systemic circulation during pregnancy. We also found that pregnancy causes more severe blood-brain barrier disruption in response to acute hypertension compared to nonpregnant animals. Aim 2 will investigate underlying mechanisms by which this occurs, including production of placental growth factor that can increase hydraulic conductivity and decrease tight junction expression. Lastly, because many women who develop eclampsia have preexisting hypertension, or preeclampsia, prior to the acute hypertensive event that causes neurologic complications, Aim 3 will use a model of hypertension in pregnancy to investigate changes in cerebral hemodynamics, blood-brain barrier properties and edema formation that may be unique compared to normal pregnancy. A powerful combination of in vivo and in vitro techniques will be used that should provide clinically relevant information regarding novel hemodynamic changes and mechanisms of edema during pregnancy and hypertension in pregnancy. Eclampsia is a leading cause of maternal death world-wide. These studies investigate underlying mechanisms by which pregnancy and hypertension during pregnancy affect the cerebral circulation in ways that promote the neurologic complications of eclampsia. This understanding is crucial to effective management and treatment of this devastating condition
Keywords: 1H-Benz(de)isoquinoline-2(3H)-carboxylic acid, 6-amino-1, 3-dioxo-5, 8-disulfo-, 2-hydrazide, dilithium salt; Acute; Address; Affect; Animals; Arterioles; Autoregulation; Blindness; Blood - brain barrier anatomy; Blood Circulation; Blood Pressure; Blood Pressure, High; Blood-Brain Barrier; Bloodstream; Brain; Brain Edema; Brain Swelling; Cause of Death; Cell Membrane Permeability; Cephalalgia; Cephalgia; Cephalodynia; Cephalodynias; Cerebral Edema; Cerebrovascular Circulation; Cerebrum; Cessation of life; Chemotherapy-Hormones/Steroids; Circulation; Clinical; Consciousness, Loss of; Convulsions; Cranial Pain; Death; Dilatation; Dilatation - action; Dropsy; Eclampsia; Edema; Emesis; Encephalon; Encephalons; Endocrine Gland Secretion; Endothelial Cells; Event; GFAC; Gestation; Gestosis, EPH; Growth Agents; Growth Factor; Growth Factors, Proteins; Growth Substances; Head Pain; Headache; Health; Hemato-Encephalic Barrier; Homeostasis; Hormonal; Hormones; Hydrops; Hydrostatic Pressure; Hypertension; Hypertensive Encephalopathy; Impairment; In Vitro; Intracranial Edema; Life; Measurement; Measures; Mediating; Methods and Techniques; Methods, Other; Microbeads; Microspheres; Modeling; Nausea; Nervous System, Brain; Neurologic; Neurological; Occluding Junctions; Organ; PGF; PGF gene; PIFG (factor); PLGF-2; Patients; Permeability; Physiological Homeostasis; PlGF; PlGF protein; Placental Growth Factor; Placental Growth Factor Gene; Pre-Eclampsia; Preeclampsia; Pregnancy; Pregnancy Complications; Pressure; Pressure- physical agent; Production; Property; Property, LOINC Axis 2; Proteinuria-Edema-Hypertension Gestosis; Relaxin; Resistance; Role; Structure; Structure of arteriole; Structure of venule; Techniques; Therapeutic Hormone; Tight Junctions; Time; Toxemias, Pregnancy; Transmission; Unconscious; Unconscious State; Unconsciousness; Vascular Hypertensive Disease; Vascular Hypertensive Disorder; Vascular remodeling; Venules; Visual; Vomiting; Woman; Zonula Occludens; arteriole; cerebral blood flow; cerebral circulation; cerebrocirculation; cerebrovascular; clinical relevance; clinically relevant; experiment; experimental research; experimental study; fetal; hemodynamics; hyperpiesia; hyperpiesis; hypertensive disease; in vitro Model; in vivo; in vivo Model; lucifer yellow; medical complication; membrane permeability; neuroimaging; novel; placenta growth factor; placenta growth factor 1, human; pregnancy hypertension; pregnancy toxemia/hypertension; pregnant; pressure; product placenta growth factor; public health relevance; research study; resistant; response; social role; transmission process; venule; wet brain
Relevance: Eclampsia is a leading cause of maternal death world-wide. These studies investigate underlying mechanisms by which pregnancy and hypertension during pregnancy affect the cerebral circulation in ways that promote the neurologic complications of eclampsia. This understanding is crucial to effective management and treatment of this devastating condition
Project start date: 2003-04-01
Project end date: 2014-01-31
Budget start date: 1-FEB-2010
Budget end date: 31-JAN-2011
PFA/PA: PA-07-070
5R01NS045940-06 (2010): $325927
5R01NS045940-04 (2006): $245950
5R01NS045940-03 (2005): $251869
5R01NS045940-02 (2004): $251869
Grants awarded to Marilyn J Cipolla
Cerebral Arteriole Function During Hyperglycemic Stroke
Marilyn J Cipolla, Associate Professor
University Of Vermont And St Agric College 85 South Prospect Street Burlington, Vt 05405
Grant 5R01NS043316-03 from National Institute Of Neurological Disorders And Stroke IRG: ZRG1
Abstract: Ischemic stroke is one of the most common pathophysiologic events affecting more than 750,000 people per year in the US. Preexisting hyperglycemia, present in ~20% of all stroke patients, is associated with enhanced reperfusion injury in the postischemic brain, including a significantly higher incidence and severity of cerebral infarction and edema formation. While most studies have focused on metabolic derangements or neuronal tissue damage during hyperglycemic stroke, our preliminary data demonstrate that there is a direct effect of glucose on the vasculature that leads to poor perfusion and increased vascular damage during ischemia and reperfusion (I/R). Our preliminary data also demonstrate that hyperglycemia upregulates signaling molecules within the vascular wall, including protein kinase C (PKC) and reactive oxygen species (ROS) that we have hypothesized has an effect on vascular function (tone, permeability) to decrease reperfusion and enhance vasogenic edema during I/R. In addition, augmented ischemia created during hyperglycemic stroke leads to enhanced reperfusion injury that further damages the vasculature. This proposal is focused on understanding 1) how elevated glucose prior to stroke affects cerebrovascular function in a way that influences postischemic reperfusion and stroke outcome, and 2) how hyperglycemia, in combination with I/R, augments vascular damage. The middle cerebral artery occlusion model in rats will be used under normoglycemic and hyperglycemic conditions to induce controlled I/R, after which penetrating brain parenchymal arterioles will be dissected from the brain tissue and studied in vitro in a pressurized arteriograph system that allows for control over intravascular pressure, measurement of lumen diameter, and perfusion with fluorescent and electron dense tracers for determination of permeability. Aim 1 of this proposal will investigate the role of glucose-induced PKC activation and ROS production in mediating changes in arteriole function prior to stroke and how those changes influence stroke outcome. Aim 2 will determine how hyperglycemia during stroke affects vascular integrity, including vascular smooth muscle and endothelial cell damage. The proposed studies are the first to specifically investigate the direct effect of I/R and hyperglycemia on small penetrating brain arterioles that are in close association with other cell types in the brain, including astrocytes, pericytes and neurons that are known to have significant interaction with the vasculature and can influence perfusion, permeability, and stroke outcome.
Keywords: arteriole, cerebrovascular system, hyperglycemia, stroke, artery occlusion, cerebral artery, disease /disorder model, glucose metabolism, ischemia, reperfusion, vascular smooth muscle, angiography, laboratory rat, radiotracer
Project start date: 2005-07-15
Project end date: 2010-04-30
5R01NS043316-03 (2007): $299957
5R01NS043316-02 (2006): $308916
1R01NS043316-01A2 (2005): $281200
REPERFUSION EFFECTS ON CEREBRAL ARTERY FUNCTION
Marilyn J Cipolla, Associate Professor
Neurologyuniversity Of Vermont & St Agric College
85 South Prospect Street
burlington, Vt 05405
Grant 5R01NS040071-03 from National Institute Of Neurological Disorders And Stroke IRG: ZRG1
Abstract: from the ) Ischemic brain injury is one of the most common pathophysiological processes affecting more than 400,000 people per year in the US in the form of stroke. Restoration of blood flow following short periods of ischemia has been shown to benefit the brain, however, experimental and clinical evidence indicates that reperfusion following longer periods of ischemia may worsen brain injury. While the effects of ischemia and reperfusion have been extensively studied in neuronal injury, little information regarding these effects on cerebral arteries, and how this dysfunction affects stroke outcome, is available. This study investigates the ischemic and reperfusion effects on cerebral artery function, focusing on myogenic tone and reactivity to pressure, both important components of vascular resistance and autoregulation of cerebral blood flow. The intraluminal suture model of focal cerebral ischemia in rats will be used to induce controlled ischemia and reperfusion in middle cerebral arteries. The arteries will then be dissected from the occluded side of the brain and studied in vitro in a system that allows control of intravascular pressure and continuous measurement of lumen diameter. Arteries will be studied under variable periods of ischemia and reperfusion to determine the threshold duration of ischemia and reperfusion that arteries can still maintain viable myogenic responses (Aim 1). Since preliminary experiments determined that 2 hours of ischemia followed by 24 hours of reperfusion results in significantly diminished reactivity to pressure and abnormal basal tone of middle cerebral arteries, we will investigate alterations in cerebral artery structure (e.g., actin cytoskeleton) and function (e.g., myogenic behavior) that may contribute to the loss of function. In addition, inhibitors of compounds known to be detrimental during ischemia and reperfusion (e.g., nitric oxide, superoxide radical) will be used to determine if cerebral artery function can be preserved during reperfusion (Aim 2). Lastly, one promising therapeutic approach involves thrombolysis to restore blood flow to ischemic regions of the brain; however, the use of thrombolytic agents carries the risk of edema formation and hemorrhage. One mechanism that may contribute to these processes during thrombolysis is an effect of the agents themselves on cerebral artery myogenic behavior. Normal cerebrovascular resistance is important during reperfusion and during treatment with thrombolytic agents if vascular integrity is to be maintained and tissue damage minimized. Therefore, Aim 3 will investigate the effects of two types of thrombolytic agents (tissue-type and urokinase) on cerebral artery function, including myogenic processes
Keywords: cerebral artery, pathologic process, reperfusion, stroke, vasomotion actin, blood pressure, cerebral ischemia /hypoxia, cytoskeleton, fibrinolytic agent, hypotonia, muscle tone, nitric oxide, superoxide, vascular resistance, vascular smooth muscle artery occlusion, biomechanics, laboratory rat, organ culture
Project start date: 1999-07-15
Project end date: 2004-03-31
5R01NS040071-03 (2001): $229108
5R01NS040071-02 (2000): $252435
1R01NS040071-01 (1999): $242134
CEREBROVASCULAR CHANGES IN PREGNANCY AND HYPERTENSION
Marilyn J Cipolla, Associate Professor
University Of Vermont & St Agric College, 85 South Prospect Street, Burlington, Vt 05405
Grant 3R01NS045940-06S1 from National Institute Of Neurological Disorders And Stroke
Abstract: Eclampsia is a serious complication of pregnancy that occurs when hypertension during pregnancy develops with neurologic complications, including headache, vomiting, blindness and convulsions. While multiple organs are affected by hypertension in pregnancy, cerebrovascular involvement is the direct cause of death in ~40% of patients. The major cerebrovascular changes that occur during eclampsia are thought to be similar to hypertensive encephalopathy in which acute elevations in pressure cause autoregulatory breakthrough, hyperperfusion and edema. Our preliminary studies found that late-pregnant animals had significantly decreased cerebrovascular resistance and hyperperfusion compared to nonpregnant animals during acute hypertension, similar to eclampsia. Importantly, only the late-pregnant animals developed cerebral edema, suggesting that pregnancy alone predisposes the brain to the neurologic complications of eclampsia when blood pressure is elevated. Because of the prominent role of edema formation in mediating the neurologic complications of eclampsia, the long-term objective of this project is understand the underlying mechanisms by which pregnancy and hypertension in pregnancy affect the cerebral circulation in a way that promotes hydrostatic brain edema during increased blood pressure. Our preliminary studies suggest for the first time that pregnancy causes outward remodeling of cerebral arterioles, an effect that likely diminishes small vessel resistance in the brain during acute hypertension. Aim 1 will therefore investigate underlying mechanisms by which pregnancy causes outward remodeling, including the hormone relaxin, known to promote vascular remodeling in the systemic circulation during pregnancy. We also found that pregnancy causes more severe blood-brain barrier disruption in response to acute hypertension compared to nonpregnant animals. Aim 2 will investigate underlying mechanisms by which this occurs, including production of placental growth factor that can increase hydraulic conductivity and decrease tight junction expression. Lastly, because many women who develop eclampsia have preexisting hypertension, or preeclampsia, prior to the acute hypertensive event that causes neurologic complications, Aim 3 will use a model of hypertension in pregnancy to investigate changes in cerebral hemodynamics, blood-brain barrier properties and edema formation that may be unique compared to normal pregnancy. A powerful combination of in vivo and in vitro techniques will be used that should provide clinically relevant information regarding novel hemodynamic changes and mechanisms of edema during pregnancy and hypertension in pregnancy. Eclampsia is a leading cause of maternal death world-wide. These studies investigate underlying mechanisms by which pregnancy and hypertension during pregnancy affect the cerebral circulation in ways that promote the neurologic complications of eclampsia. This understanding is crucial to effective management and treatment of this devastating condition
Keywords: 1H-Benz(de)isoquinoline-2(3H)-carboxylic acid, 6-amino-1, 3-dioxo-5, 8-disulfo-, 2-hydrazide, dilithium salt; Acute; Address; Affect; Animals; Arterioles; Autoregulation; Blindness; Blood - brain barrier anatomy; Blood Circulation; Blood Pressure; Blood Pressure, High; Blood-Brain Barrier; Bloodstream; Brain; Brain Edema; Brain Swelling; Cause of Death; Cell Membrane Permeability; Cephalalgia; Cephalgia; Cephalodynia; Cephalodynias; Cerebral Edema; Cerebrovascular Circulation; Cerebrum; Cessation of life; Chemotherapy-Hormones/Steroids; Circulation; Clinical; Consciousness, Loss of; Convulsions; Cranial Pain; Death; Dilatation; Dilatation - action; Dropsy; Eclampsia; Edema; Emesis; Encephalon; Encephalons; Endocrine Gland Secretion; Endothelial Cells; Event; GFAC; Gestation; Gestosis, EPH; Growth Agents; Growth Factor; Growth Factors, Proteins; Growth Substances; Head Pain; Headache; Health; Hemato-Encephalic Barrier; Homeostasis; Hormonal; Hormones; Hydrops; Hydrostatic Pressure; Hypertension; Hypertensive Encephalopathy; Impairment; In Vitro; Intracranial Edema; Life; Measurement; Measures; Mediating; Methods and Techniques; Methods, Other; Microbeads; Microspheres; Modeling; Nausea; Nervous System, Brain; Neurologic; Neurological; Occluding Junctions; Organ; PGF; PGF gene; PIFG (factor); PLGF-2; Patients; Permeability; Physiological Homeostasis; PlGF; PlGF protein; Placental Growth Factor; Placental Growth Factor Gene; Pre-Eclampsia; Preeclampsia; Pregnancy; Pregnancy Complications; Pressure; Pressure- physical agent; Production; Property; Property, LOINC Axis 2; Proteinuria-Edema-Hypertension Gestosis; Relaxin; Resistance; Role; Structure; Structure of arteriole; Structure of venule; Techniques; Therapeutic Hormone; Tight Junctions; Time; Toxemias, Pregnancy; Transmission; Unconscious; Unconscious State; Unconsciousness; Vascular Hypertensive Disease; Vascular Hypertensive Disorder; Vascular remodeling; Venules; Visual; Vomiting; Woman; Zonula Occludens; arteriole; cerebral blood flow; cerebral circulation; cerebrocirculation; cerebrovascular; clinical relevance; clinically relevant; experiment; experimental research; experimental study; fetal; hemodynamics; hyperpiesia; hyperpiesis; hypertensive disease; in vitro Model; in vivo; in vivo Model; lucifer yellow; medical complication; membrane permeability; neuroimaging; novel; placenta growth factor; placenta growth factor 1, human; pregnancy hypertension; pregnancy toxemia/hypertension; pregnant; pressure; product placenta growth factor; public health relevance; research study; resistant; response; social role; transmission process; venule; wet brain
Relevance: Eclampsia is a leading cause of maternal death world-wide. These studies investigate underlying mechanisms by which pregnancy and hypertension during pregnancy affect the cerebral circulation in ways that promote the neurologic complications of eclampsia. This understanding is crucial to effective management and treatment of this devastating condition
Project start date: 2003-04-01
Project end date: 2014-01-31
Budget start date: 1-FEB-2010
Budget end date: 31-JAN-2011
PFA/PA: PA-07-070
3R01NS045940-06S1 (2010): $75750
3R01NS045940-05A2S1 (2009): $220499
1R01NS045940-01 (2003): $239148
Sponsored Links Excellgen http://Excellgen.com
REPERFUSION EFFECTS ON CEREBRAL ARTERY FUNCTION
Marilyn J Cipolla, Associate Professor
Surgeryoregon Health & Science University
3181 Sw Sam Jackson Pk Rd
portland, Or 972393098
Grant 3R55NS037854-01S1 from National Institute Of Neurological Disorders And Stroke IRG: ZRG1
Keywords: cerebral artery, cerebral ischemia /hypoxia, reperfusion, stroke actin, blood pressure, fibrinolysis, myogenesis, nitric oxide, superoxide, urokinase, vasomotion electromyography, laboratory rat
Project start date: 1998-09-15
Project end date: 1999-07-14
3R55NS037854-01S1 (1999): $30000
1R55NS037854-01 (1998): $100000