Haydee  E. P.  Bazan, Ph.D.

Current Research

Dr. Haydee E.P Bazan's laboratory studies lipid second messengers in the cornea, particularly platelet activating factor (PAF), a potent lipid mediator of inflammatory and immunological responses and lipoxygenease derivatives from the arachidonic cascade. The laboratory has demonstrated that PAF is generated in retina and cornea after injury (e.g., laser photocoagulation, chemical burns in the eye) and that PAF mediates its action through receptors. Dr. Bazan's laboratory has discovered that this particular lipid induces the expression of selective metalloproteinases (MMPs) – MMP-9, MMP-1 and MT1-MMP – involved in the degradation of components of the extracellular matrix (ECM) that are very important in the process of tissue repair. PAF also induces the expression of genes such as cyclooxygenase-2 (COX-2), increasing the synthesis of prostaglandins and producing sustained inflammation in the eye. On the other hand, 12/15 lipoxygenease derivatives are mediators in the repair action of EGF after corneal injury. Another research interest is the study of cell signal transduction events during corneal wound healing, particularly how specific growth factors (HGF, KGF and EGF) are released during injury activate kinases and phosphatases to communicate their signals from the cell membrane to the nuclei. A third project  in the laboratory is the action of lipid mediators derived from docosahexaenoic acid (DHA) in combination with pigment epithelial derived growth factor (PEDF) on nerve regrowth after corneal wounding. Because corneal nerves are important in the maintenance of corneal integrity and prevention of dry eye following surgery, these studies are of clinical significance. Several animal models, as well as cells and organ cultures, are used. Analytical procedures such as liquid chromatography and mass spectrometry, a variety of molecular biology techniques such as real time PCR, siRNAs, Western blot, immunoprecipitations, kinase assays and immunofluorescence are employed.