Differential gene expression in the mouse hippocampus following controlled cortical impact brain injury / Paolo Marciano' Agostinelli.

Format:

Book

Manuscript

Microformat

Thesis/Dissertation

Author/Creator:

Marciano' Agostinelli, Paolo.

Contributor:

McIntosh, Tracy K., advisor.

Eberwine, James H., advisor.

University of Pennsylvania.

Language:

English

Subjects (All):

Penn dissertations--Neuroscience.

Neuroscience--Penn dissertations.

Neurosciences.

Academic Dissertations as Topic.

Medical Subjects:

Neurosciences.

Academic Dissertations as Topic.

Local Subjects:

Penn dissertations--Neuroscience.

Neuroscience--Penn dissertations.

Physical Description:

xi, 187 pages ; 29 cm

Production:

2002.

Summary:

Traumatic brain injury is a predominant cause of death in the modern world, however little is known about the underlying pathobiology. Experimental models of closed-head injury, such as controlled cortical impact (CCI) in the mouse, closely approximate the physiological and behavioral alterations that occur in brain-injured patients. Previously, cell death in these regions was thought to be necrotic, however, our data demonstrates that apoptosis, occurring through a presumed intrinsic molecular cascade culminating in the activation of caspases, plays a major role. Altered gene expression is critical to the progression of apoptosis, therefore, identification of transcriptional changes involved could elucidate specific molecular events that subserve the neurobehavioral deficits observed following brain injury. Analyses using whole tissue homogenates can dramatically skew the relative quantities of molecular mediators, potentially masking vital mRNA abundance changes. Reducing heterogeneity to that expressed in a single neuron holds the promise to reveal new molecular cascades essential the regional apoptosis observed. Antisense mRNA was amplified from single, apoptotic and putatively pre-apoptotic dentate or CA3 neurons and used to probe DNA microarrays allowing for the concurrent examination of over 8,000 mouse mRNAs. The mRNAs were randomly selected from the mouse genome providing the ability to impartially monitor genes both presently unknown or not currently associated with the apoptotic cascade. On a global level, the resulting data demonstrates that pooled single neurons expressed approximately 32% of the clones spotted on the array, of which, only 3.5% were differentially expressed greater than 1.3 fold. Even though the number of clones differentially regulated varied, expression relative to uninjured counterparts never exceeded 4.76 fold and was on average 2.0 fold. The analysis also demonstrated that both apoptotic and putatively pre-apoptotic neurons in both regions differentially expressed (greater than 1.5 fold) a completely different set of genes. These molecularly distinct apoptotic cascades could underlie the regional specific susceptibility evidenced by the different time course of apoptosis in the hippocampus. Identification of these complex genetic events that are specific to vulnerable cell populations can contribute to the design of novel therapeutics for use following human brain injury.

Notes:

Thesis (Ph.D. in Neuroscience) -- University of Pennsylvania, 2002.

Includes bibliographical references.

Local Notes:

University Microfilms order no.: 3058737.

OCLC:

244972071