Visiting Scholar Presentation: A Concept of Meibogenesis from Genomic and Lipidomic Points of View

Monday, 3 December, 2018 - 15:00


Please join us in welcoming Associate Professor Igor Butovich from the University of Texas Southwestern, USA who give a talk on "The recent advances in the Meibomian gland studies with the emphasis on the main features of the lipid biosynthesis in Meibomian glands". All staff, students, alumni and public are more than welcome to attend.

Relevant details are as follows:

Title: A Concept of Meibogenesis from Genomic and Lipidomic Points of View

Date/Time: Monday 3 December 2018 - 3pm – 4pm

Location: Rupert Myers Theatre, North Wing Rupert Myers Building, Gate 14 Barker Street, UNSW Sydney NSW 2052

UNSW School: School of Optometry and Vision Science

Succinct descriptive first sentence: The recent advances in the Meibomian gland studies with the emphasis on the main features of the lipid biosynthesis in Meibomian glands

Event Description:
Meibum is a lipid-rich secretion that is produced by fully differentiated meibocytes in the holocrine Meibomian glands (MG) of humans and most mammals. The secretion is a part of a defense mechanism that protects the ocular surface from hazardous environmental factors, and from desiccation. Meibomian lipids that have been identified in meibum are very diverse and unique in nature. The lipid composition of meibum is different from virtually any other lipid pool found in the human body. In fact, meibum is quite different from sebum, which is the closest secretion that is produced by anatomically, physiologically, and biochemically related sebaceous glands. However, meibum of mice have been shown to closely resemble that of humans, implying similar biosynthetic mechanisms in MG of both species. By analyzing available genomic, immunohistochemical, and lipidomic data, we have envisioned a unifying network of enzymatic reactions that are responsible for biosynthesis of meibum, which we call meibogenesis. Our current theory is based on an assumption that most of the biosynthetic reactions of meibogenesis are catalyzed by known enzymes. However, the main features that make meibum unique - the ratio of identified classes of lipids, the extreme length of its components, extensive ω-hydroxylation of fatty acids and alcohols, iso- and anteiso-branching of meibomian lipids (e.g. waxes), and the presence of rather unique complex lipids with several ester bonds - make it possible that either the activity of known enzymes is altered in MG, or some unknown enzymes contribute to the processes of meibogenesis, or both. Studies are in progress to elucidate meibogenesis on molecular level.

Speaker Biography:
Dr Igor A. Butovich is an Associate Professor with the Department of Ophthalmology and the Graduate School of Biomedical Sciences, University of Texas Southwestern Medical Center and Adjunct Associate Professor in North Texas Eye Research Institute.

His research interests include lipidomics, enzymology, drug discovery, and bioanalytical chemistry in relation to ocular biochemistry, biophysics, and physiology. Experimental approaches he uses include high-performance liquid chromatography (HPLC); gas chromatography (GC); mass spectrometry and its combinations with HPLC and MS; nuclear magnetic resonance spectroscopy (NMR) and ultraviolet (UV) spectrometry.

His work is currently focused on the causes of dry eye syndrome, and finding the best treatments for it. To pursue these goals he has developed novel experimental and theoretical approaches in the areas of lipidomics, proteomics, and biophysics of tear films. He is interested in comparative biochemical and biophysical analyses of the human and animal tear film to identify the best functional animal model of the human tear film. Developing such a model can provide vital information on the structure, composition, and physiology of tear film in different species and in turn, will be used to find a way to repair the damaged tear film in dry eye patients, and possibly to enhance the normal tear film in healthy individuals.