Medicine and Health Sciences Commons^™

Global Profiling Of Alternative Splicing Events And Gene Expression Regulated By Hnrnph/F, Erming Wang, Vahid Aslanzadeh, Filomena Papa, Haiyan Zhu, Pierre De La Grange, Franca Cambi

Neurology Faculty Publications

In this study, we have investigated the global impact of heterogeneous nuclear Ribonuclear Protein (hnRNP) H/F-mediated regulation of splicing events and gene expression in oligodendrocytes. We have performed a genome-wide transcriptomic analysis at the gene and exon levels in Oli-neu cells treated with siRNA that targets hnRNPH/F compared to untreated cells using Affymetrix Exon Array. Gene expression levels and regulated exons were identified with the GenoSplice EASANA algorithm. Bioinformatics analyses were performed to determine the structural properties of G tracts that correlate with the function of hnRNPH/F as enhancers vs. repressors of exon inclusion. Different types of alternatively spliced events …

The P2y(12) Antagonists, 2mesamp And Cangrelor, Inhibit Platelet Activation Through P2y(12)/G(I)-Dependent Mechanism, Binggang Xiang, Guoying Zhang, Hongmei Ren, Manjula Sunkara, Andrew J. Morris, T. Kent Gartner, Susan S. Smyth, Zhenyu Li

Saha Cardiovascular Research Center Faculty Publications

BACKGROUND: ADP is an important physiological agonist that induces integrin activation and platelet aggregation through its receptors P2Y(1) (Gα(q)-coupled) and P2Y(12) (Gα(i)-coupled). P2Y(12) plays a critical role in platelet activation and thrombosis. Adenosine-based P2Y(12) antagonists, 2-methylthioadenosine 5'-monophosphate triethylammonium salt hydrate (2MeSAMP) and Cangrelor (AR-C69931MX) have been widely used to demonstrate the role of P2Y(12) in platelet function. Cangrelor is being evaluated in clinical trials of thrombotic diseases. However, a recent study reported that both 2MeSAMP and Cangrelor raise intra-platelet cAMP levels and inhibit platelet aggregation through a P2Y(12)-independent mechanism.

METHODOLOGY/PRINCIPAL FINDINGS: The present work, using P2Y(12) deficient mice, sought to …

Fak Is A Critical Regulator Of Neuroblastoma Liver Metastasis, Sora Lee, Jingbo Qiao, Pritha Paul, Kathleen L. O'Connor, B. Mark Evers, Dai H. Chung

Surgery Faculty Publications

Neuroblastomas express increased levels of gastrin-releasing peptide receptor (GRP-R). However, the exact molecular mechanisms involved in GRP-R-mediated cell signaling in neuroblastoma growth and metastasis are unknown. Here, we report that focal adhesion kinase (FAK), as a critical downstream target of GRP-R, is an important regulator of neuroblastoma tumorigenicity. We found that FAK expression correlates with GRP-R expression in human neuroblastoma sections and cell lines. GRP-R overexpression in SK-N-SH cells increased FAK, integrin α3 and β1 expressions and cell migration. These cells demonstrated flatter cell morphology with broad lamellae, in which intense FAK expression was localized to the leading edges of …

Characterization Of Secretory Sphingomyelinase Activity, Lipoprotein Sphingolipid Content And Ldl Aggregation In Ldlr-/- Mice Fed On A High-Fat Diet, Gergana M. Deevska, Manjula Sunkara, Andrew J. Morris, Mariana N. Nikolova‑Karakashian

Physiology Faculty Publications

The propensity of LDLs (low-density lipoproteins) for aggregation and/or oxidation has been linked to their sphingolipid content, specifically the levels of SM (sphingomyelin) and ceramide. To investigate this association in vivo, ldlr (LDL receptor)-null mice (ldlr-/-) were fed on a modified (atherogenic) diet containing saturated fats and cholesterol. The diet led to significantly elevated SM content in all serum lipoproteins. In contrast, ceramide increased only in the LDL particles. MS-based analyses of the lipid acyl chain composition revealed a marked elevation in C16:0 fatty acid in SM and ceramide, consistent with the prevalence of palmitic acid in the modified diet. …

Perlecan Domain V Induces Vegf Secretion In Brain Endothelial Cells Through Integrin Α5Β1 And Erk-Dependent Signaling Pathways, Douglas N. Clarke, Abraham Al Ahmad, Boyeon Lee, Christi Parham, Lisa Auckland, Andrezj Fertala, Michael Kahle, Courtney S. Shaw, Jill Roberts, Gregory J. Bix

Sanders-Brown Center on Aging Faculty Publications

Perlecan Domain V (DV) promotes brain angiogenesis by inducing VEGF release from brain endothelial cells (BECs) following stroke. In this study, we define the specific mechanism of DV interaction with the α(5)β(1) integrin, identify the downstream signal transduction pathway, and further investigate the functional significance of resultant VEGF release. Interestingly, we found that the LG3 portion of DV, which has been suggested to possess most of DV's angio-modulatory activity outside of the brain, binds poorly to α(5)β(1) and induces less BEC proliferation compared to full length DV. Additionally, we implicate DV's DGR sequence as an important element for the interaction …

Atovaquone Ameliorate Gastrointestinal Toxoplasmosis Complications In A Pregnancy Model, Helieh S. Oz, Thomas Tobin

Physiology Faculty Publications

Background: Toxoplasma is an important source of foodborne hospitalization with no safe and effective therapy against chronic or congenital Toxopalsmosis. Atovaquone is a drug of choice but not approved for use in congenital Toxoplasmosis. We hypothesized atovaquone to be safe and effective against feto-maternal Toxoplasmosis.

Material/Methods: Programmed pregnant mice were i.p. infected with 50–2400 Tachyzoites from Type II strain (clone PTG). Dams were treated daily with atovaquone or sham and monitored for pain, and complications.

Results: Dams developed pain related abdominal hypersensitivity (allodynia) to mechanical stimuli in a Tachyzoites dose dependent manner. Infected dams were anemic and exhibited ascities and …

Early Stage Drug Treatment That Normalizes Proinflammatory Cytokine Production Attenuates Synaptic Dysfunction In A Mouse Model That Exhibits Age-Dependent Progression Of Alzheimer's Disease-Related Pathology, Adam D. Bachstetter, Christopher M. Norris, Pradoldej Sompol, Donna M. Wilcock, Danielle Goulding, Janna H. Neltner, Daret St. Clair, D. Martin Watterson, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

Overproduction of proinflammatory cytokines in the CNS has been implicated as a key contributor to pathophysiology progression in Alzheimer's disease (AD), and extensive studies with animal models have shown that selective suppression of excessive glial proinflammatory cytokines can improve neurologic outcomes. The prior art, therefore, raises the logical postulation that intervention with drugs targeting dysregulated glial proinflammatory cytokine production might be effective disease-modifying therapeutics if used in the appropriate biological time window. To test the hypothesis that early stage intervention with such drugs might be therapeutically beneficial, we examined the impact of intervention with MW01-2-151SRM (MW-151), an experimental therapeutic that …

Inhibition Of Fatty Acid Synthase Attenuates Cd44-Associated Signaling And Reduces Metastasis In Colorectal Cancer, Yekaterina Y. Zaytseva, Piotr G. Rychahou, Pat Gulhati, Victoria Allison Elliott, William Conan Mustain, Kathleen O'Connor, Andrew J. Morris, Manjula Sunkara, Heidi L. Weiss, Eun Young Lee, B. Mark Evers

Markey Cancer Center Faculty Publications

Fatty acid synthase (FASN) and ATP-citrate lyase, key enzymes of de novo lipogenesis, are significantly upregulated and activated in many cancers and portend poor prognosis. Even though the role of lipogenesis in providing proliferative and survival advantages to cancer cells has been described, the impact of aberrant activation of lipogenic enzymes on cancer progression remains unknown. In this study, we found that elevated expression of FASN is associated with advanced stages of colorectal cancer (CRC) and liver metastasis, suggesting that it may play a role in progression of CRC to metastatic disease. Targeted inhibition of lipogenic enzymes abolished expression of …

Krüppel-Like Factor 4 Regulates Intestinal Epithelial Cell Morphology And Polarity, Tianxin Yu, Xi Chen, Wen Zhang, Juan Li, Ren Xu, Timothy C Wang, Walden Ai, Chunming Liu

Markey Cancer Center Faculty Publications

Krüppel-like factor 4 (KLF4) is a zinc finger transcription factor that plays a vital role in regulating cell lineage differentiation during development and maintaining epithelial homeostasis in the intestine. In normal intestine, KLF4 is predominantly expressed in the differentiated epithelial cells. It has been identified as a tumor suppressor in colorectal cancer. KLF4 knockout mice demonstrated a decrease in number of goblet cells in the colon, and conditional ablation of KLF4 from the intestinal epithelium led to altered epithelial homeostasis. However, the role of KLF4 in differentiated intestinal cells and colon cancer cells, as well as the mechanism by which …

Lithium Treatment Of Appswdi/Nos2−/− Mice Leads To Reduced Hyperphosphorylated Tau, Increased Amyloid Deposition And Altered Inflammatory Phenotype, Tiffany L. Sudduth, Joan G. Wilson, Angela Everhart, Carol A. Colton, Donna M. Wilcock

Sanders-Brown Center on Aging Faculty Publications

Lithium is an anti-psychotic that has been shown to prevent the hyperphosphorylation of tau protein through the inhibition of glycogen-synthase kinase 3-beta (GSK3β). We recently developed a mouse model that progresses from amyloid pathology to tau pathology and neurodegeneration due to the genetic deletion of NOS2 in an APP transgenic mouse; the APPSwDI/NOS2-/- mouse. Because this mouse develops tau pathology, amyloid pathology and neuronal loss we were interested in the effect anti-tau therapy would have on amyloid pathology, learning and memory. We administered lithium in the diets of APPSwDI/NOS2-/- mice for a period of eight months, followed by water maze …