Human trabecular meshwork sphingolipid and ceramide profiles and potential latent fungal commensalism.
OBJECTIVE
We determined the profiles of sphingomyelin, sphingoid base, sphingoid base-1-phosphate, and ceramide, and their quantitative differences between control and glaucomatous trabecular meshwork (TM) derived from human donors.


METHODS
Control and primary open angle glaucoma (POAG) TM samples were collected from cadaver donors. In addition, POAG TM surgical specimens also were procured. Lipid extraction was performed using suitable modifications of the Bligh and Dyer method. Protein concentrations were determined using Bradford's method. Lipids, identified using standardized class-specific lipid mass spectrometry, were quantified using a two-step ratiometric process. Gomori methenamine silver (GMS) staining was performed for detection of presence of Fusarium in the anterior eye tissue sections. PCR analyses were performed for detection of Fusarium species in the donor TM samples.


RESULTS
Several species of sphingomyelin, sphingoid base, sphingoid base-1-phosphate, and ceramide were common between control and POAG TM. Only a subset of species in some of these classes were identified uniquely either in controls or in POAG TM. Several lipid species of fungal origin (many from Fungi imperfecti, Fusarium species) were found to be common between control and POAG TM. The GMS staining and PCR analyses showed presence of DNA belonging to Fusarium species suggesting latent commensalism.


CONCLUSIONS
Most sphingolipids and ceramides (except a few unique to a specific donor TM group) were found to be common in the control and POAG TM. Latent commensalism by Fusarium was suggested by identification of Fusarium-specific lipids, which was supported further by PCR amplification and sequencing of DNA.
Bascom Palmer Eye Institute, University of Miami, Miami, Florida, United States.
Ayman J
AJ
Aljohani
Bascom Palmer Eye Institute, University of Miami, Miami, Florida, United States.
Genea
G
Edwards
Bascom Palmer Eye Institute, University of Miami, Miami, Florida, United States.
Yenifer
Y
Guerra
Bascom Palmer Eye Institute, University of Miami, Miami, Florida, United States.
Sander
S
Dubovy
Bascom Palmer Eye Institute, University of Miami, Miami, Florida, United States.
Darlene
D
Miller
Bascom Palmer Eye Institute, University of Miami, Miami, Florida, United States.
Richard K
RK
Lee
Bascom Palmer Eye Institute, University of Miami, Miami, Florida, United States.
Sanjoy K
SK
Bhattacharya
D000368:Aged; D002102:Cadaver; D002518:Ceramides / Q000378:metabolism*; D004271:DNA, Fungal / Q000032:analysis; D015821:Eye Infections, Fungal / Q000378:metabolism* / Q000382:microbiology / Q000473:pathology; D005260:Female; D060585:Fusariosis / Q000150:complications / Q000378:metabolism* / Q000382:microbiology; D005670:Fusarium / Q000502:physiology*; D005902:Glaucoma, Open-Angle / Q000150:complications / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D013107:Sphingolipids / Q000378:metabolism*; D013559:Symbiosis; D014129:Trabecular Meshwork / Q000378:metabolism* / Q000382:microbiology / Q000473:pathology
D002518:Ceramides; D004271:DNA, Fungal; D013107:Sphingolipids
ceramide; glaucoma; lipidomics; sphingolipid; trabecular meshwork