Catalin Filipeanu, MD, PhD

Assistant Research Professor

CoBRE Junior Investigator

Department of Pharmacology and Experimental Therapeutics

Cardiovascular Center of Excellence

LSUHSC – MedicalEducationBuilding, Room 5201,

1901 Perdido Street, New Orleans, LA 70112

Phone: (504) 568 4514

Fax: (504) 568 2361

Email: cfilip@lsuhsc.edu

 

Degrees

M.D. – 1996, University of Medicine “Gr. T. Popa”, Iasi, Romania

Ph.D. – 2001, Rijksuniversiteit Groningen, The Netherlands

            Thesis: “Intracellular angiotensin: from myth to reality.”

 

Bio

Catalin Filipeanu become interested in cell physiology while being a medical student and he started working in the Dr. Branisteanu”s lab. After obtaining his MD in 1996, he was awarded the “Ubbo Emmius” fellowship from Dutch Ministry of Foreign Affairs and attended Rijksuniversiteit Groningen, where in 2001 he obtained his Ph.D. in Molecular Pharmacology. The subject of his thesis was on the intracellular effects of angiotensin II. From 2001 to 2003, he worked as a Postdoctoral Fellow with Dr. Nae Dun on the central and peripheral effects of urotensin II. In 2004, he moved to the Department of Pharmacology at LSUHSC-NO where he continued his postdoctoral training with Dr. Guangyu Wu studying the regulation of intracellular protein transport. In November 2007, he was promoted to his first faculty position, as Research Assistant Professor in the Department of Pharmacology and Experimental Therapeutics, LSUHSC.

 

Research Interests

My primary project concentrates on the elucidation of the pathologic mechanisms involved in Raynaud Phenomenon. Cold-induced constriction of peripheric arteries is a normal response contributing to preservation of body temperature. In some individuals this response is exaggerated and leads to painful discoloration of the fingers, toes and other extremities. These are manifestations of Raynaud Phenomenon. Experimental evidence supports a role of α2C-adrenergic receptors in these symptoms. At 37oC, α2C-AR is poorly transported to the cell surface and accumulates inside the cell. Exposure to low temperature is enhancing its transport to the plasma membrane and increases the vasoconstrictor response to circulating cathecolamines. Currently, using molecular and cell biology approaches, we are characterizing the mechanisms limiting the α2C-AR transport to the cell surface.

 

Other current projects in the lab are focusing on understanding the role of molecular chaperones in the receptor trafficking, transport to the cell surface and signaling modulation.

 

 

The subcellular localization of GFP-tagged α2C-AR at 37oC and at 30oC.

HEK293T were transfected with 1 μg per 10 cm2 plate with GFP-tagged receptors and processed in the same way as for radio-ligand binding. To detect the endoplasmic reticulum and the lysosomes, the cells were co-transfected with pDsRed2-ER or DsRed2-Rab7. The plasma membrane and cis-Golgi were stained using specific markers (Na+/K+ ATP-ase and GM130 respectively) as described in Material and Methods. After cell fixation with 4% paraformaldehyde–4% sucrose mixture, the distribution of α2C-AR was analyzed by fluorescence microscopy. Blue: DNA staining by 4,6-diamidino-2-phenylindole (nuclear), green: GFP-α2C-AR, red: specific organelle indicated in the figure, yellow: co-localization of the receptor with the respective organelle marker. The images are representative from at least four different coverslips.

 

Selected Publications

Filipeanu CM, de Vries R, Danser AH, Kapusta DR.Modulation of α2C adrenergic receptor temperature-sensitive trafficking by HSP90. Biochim Biophys Acta. - Molecular Cell Research, in press.

Winsauer PJ,  Daniel JM, FilipeanuCM, LeonardST, Hulst JL, Rodgers SP, Lassen-Greene CL, Sutton JL. Long-term behavioral and pharmacodynamic effects of delta-9-tetrahydrocannabinol in female rats depend on ovarian hormone status. Addiction Biology, 2011; 16:64-81.

Feng Y, Yue X, Xia H, Bindom SM, Hickman PJ, Filipeanu CM, Wu G, Lazartigues E.Angiotensin-converting enzyme 2 overexpression in the subfornical organ prevents the angiotensin II-mediated pressor and drinking responses and is associated with angiotensin II type 1 receptor downregulation. Circ Res. 2008; 102(6):729-36.

Dong C, Filipeanu CM, Duvernay MT, Wu G. Regulation of G protein-coupled receptor export trafficking. Biochim Biophys Acta. 2007; 1768(4):853-70.

Filipeanu CM, Zhou F, Lam ML, Kerut KE, Claycomb WC, Wu  G.Enhancement of the recycling and activation of beta-adrenergic receptor by Rab4 GTPase in cardiac myocytes. J Biol Chem. 2006; 281(16):11097-103.

Filipeanu C, Zhou F, Fugetta E, Wu G. Differential regulation of the cell-surface targeting and function of β- and α1-adrenergic receptors by Rab1 GTPase in cardiac myocytes. Mol Pharmacol. 2006; 69(5):1571-84.

Zhou F, Filipeanu CM, Duvernay MT, Wu G. Cell-surface targeting of alpha2-adrenergic receptors - Inhibition by a transport deficient mutant through dimerization. Cell Signal. 2006; 18(3):318-27.

Duvernay MT, Filipeanu CM, Wu G. The regulatory mechanisms of export trafficking of G protein-coupled receptors. Cell Signal. 2005; 17(12):1457-65.

Filipeanu CM, Zhou F, Claycomb WC, Wu G.Regulation of the cell surface expression and function of angiotensin II type 1 receptor by Rab1-mediated endoplasmic reticulum-to-Golgi transport in cardiac myocytes. J Biol Chem. 2004; 279(39):41077-84.

Filipeanu CM, Brailoiu E, Le Dun S, Dun NJ.Urotensin-II regulates intracellular calcium in dissociated rat spinal cord neurons. J Neurochem. 2002; 83(4):879-84.

Filipeanu CM, Henning RH, de Zeeuw D, Nelemans A.Intracellular Angiotensin II and cell growth of vascular smooth muscle cells. Br J Pharmacol. 2001; 132(7):1590-6.