early-pathological-magnetic-resonance-detection-cerebral-injury-using

Early Pathological and Magnetic Resonance Detection of Cerebral Injury Using a Rat Model of Neonatal Hypoxic Ischemic Encephalopathy

Perinatal hypoxic-ischemic encephalopathy (HIE) is an acute disease that may afflict newborns, resulting in variable long- and short-term ...

University of Oklahoma Health Sciences Center

Caveolin-1 (Cav-1), the signature protein of caveolae is expressed in several cell types in the adult retina and is linked to ocular pathologies including uveitis, diabetic retinopathy, and primary open angle glaucoma. Genetic ablation of Cav-1 causes retinal functional deficits due to disruptions in environmental homeostasis. To better understand Cav-1 function in the retina, we examined its expression/localization during postnatal retinal development. From P0-P5, Cav-1 was detected only in the developing superficial retinal vessels, in hyaloid and choroidal vasculature, and in the retinal pigment epithelium (RPE). At P7, staining began to be observed centrally in radial cells in the neuroretina, and this staining increased dramatically by P9/10 in identifiable Müller glia. Prominent vascular staining continued throughout development. These results support the idea that Cav-1 is an indicator of Müller glial differentiation and suggests that it plays an important role in Müller cell function. 

Spatial and temporal localization of caveolin-1 protein in the developing retina.

Surfactant protein A (SP-A) up-regulates cytokine expression in lung disease of prematurity. Here we present data that for the first time characterizes SP-A expression and localization in the mouse retina and its impact on neovascularization (NV) in the mouse.

Pulmonary surfactant protein a is expressed in mouse retina by Müller cells and impacts neovascularization in oxygen-induced retinopathy.

The collectins family encompasses several collagenous Ca-dependent defense lectins that are described as pathogen recognition molecules. They play an important role in both adaptive and innate immunity. Surfactant proteins A and D are two of these proteins which were initially discovered in association with surfactant in the pulmonary system. The structure, immune and inflammatory functions, and genetic variations have been well described in relation to their roles, function and pathophysiology in the pulmonary system. Subsequently, these proteins have been discovered in a wide range of other organs and organ systems. The role of these proteins outside the pulmonary system is currently an active area of research. This review intends to provide a current overview of the genetics, structure and extra-pulmonary functions of the surfactant collectin proteins.

Structure, genetics and function of the pulmonary associated surfactant proteins A and D: The extra-pulmonary role of these C type lectins.

Surfactant proteins are important collectin immune molecules with a wide distribution throughout the body, including the ocular system. Mice with gene deletions for the surfactant protein genes Sftpa1 and Sftpd were observed to have visual impairment and thinning of the outer nuclear layers of the retina. We hypothesized that gene deletion of Sftpa1 and Sftpd (Sftpa1tm1Kor/J and Sftpd-/-) results in early retinal degeneration in these mice. Sftpa1tm1Kor/J and Sftpd-/- retinas were evaluated by histopathology and optical coherence tomography (OCT). Retinas from Sftpa1tm1Kor/J and Sftpd -/- mice showed early retinal degeneration with loss of the outer nuclear layer. After screening of mice for known retinal degeneration mutations, the mice were found to carry a previously unrecognized Pde6brd1 genotype which resulted from earlier breeding of the strain with Black Swiss mice during their generation. The mutation was outbred and the genotype of Sftpa1tm1Kor/J and Sftpd-/- was confirmed. Outbreeding of the Pde6brd1 mutation resulted in restoration of normal retinal architecture confirmed by in vivo and in vitro examination. We can therefore conclude that loss of Sftpa1 and Sftpd do not result in retinal degeneration. We have now generated retinal Sftpa1 and Sftpd targeted mice that exhibit normal retinal histology.

Retinal degeneration mutation in Sftpa1tm1Kor/J and Sftpd -/- targeted mice.

To investigate recombinant human insulin-like growth factor 1 complexed with its binding protein (rhIGF-1/rhIGFBP-3) for the prevention of retinopathy of prematurity (ROP) and other complications of prematurity among extremely preterm infants.

rhIGF-1/rhIGFBP-3 in Preterm Infants: A Phase 2 Randomized Controlled Trial.

During the progression of ocular diseases such as retinopathy of prematurity and diabetic retinopathy, overgrowth of retinal blood vessels results in the formation of pathological neovascular tufts that impair vision. Current therapeutic options for treating these diseases include antiangiogenic strategies that can lead to the undesirable inhibition of normal vascular development. Therefore, strategies that eliminate pathological neovascular tufts while sparing normal blood vessels are needed. In this study we exploited the hyaloid vascular network in murine eyes, which naturally undergoes regression after birth, to gain mechanistic insights that could be therapeutically adapted for driving neovessel regression in ocular diseases. We found that endothelial cells of regressing hyaloid vessels underwent down-regulation of two structurally related E-26 transformation-specific (ETS) transcription factors, ETS-related gene (ERG) and Friend leukemia integration 1 (FLI1), prior to apoptosis. Moreover, the small molecule YK-4-279, which inhibits the transcriptional and biological activity of ETS factors, enhanced hyaloid regression in vivo and drove Human Umbilical Vein Endothelial Cells (HUVEC) tube regression and apoptosis in vitro. Importantly, exposure of HUVECs to sheer stress inhibited YK-4-279-induced apoptosis, indicating that low-flow vessels may be uniquely susceptible to YK-4-279-mediated regression. We tested this hypothesis by administering YK-4-279 to mice in an oxygen-induced retinopathy model that generates disorganized and poorly perfused neovascular tufts that mimic human ocular diseases. YK-4-279 treatment significantly reduced neovascular tufts while sparing healthy retinal vessels, thereby demonstrating the therapeutic potential of this inhibitor.

An inhibitor of endothelial ETS transcription factors promotes physiologic and therapeutic vessel regression.

To determine the associations of presence and types of cardiovascular diseases (CVDs) with development of retinopathy of prematurity (ROP) in premature infants undergoing ROP examinations.

Faizah Bhatti

Department of Pediatrics,
Center for Neuroscience

University of Oklahoma Health Sciences Center

Early Pathological and Magnetic Resonance Detection of Cerebral Injury Using a Rat Model of Neonatal Hypoxic Ischemic Encephalopathy

Faizah Bhatti

Department of Pediatrics,Center for Neuroscience

University of Oklahoma Health Sciences Center

Early Pathological and Magnetic Resonance Detection of Cerebral Injury Using a Rat Model of Neonatal Hypoxic Ischemic Encephalopathy

Department of Pediatrics,
Center for Neuroscience