Transcriptome analysis of aging mouse meibomian glands.
OBJECTIVE
Dry eye disease is a common condition associated with age-related meibomian gland dysfunction (ARMGD). We have previously shown that ARMGD occurs in old mice, similar to that observed in human patients with MGD. To begin to understand the mechanism underlying ARMGD, we generated transcriptome profiles of eyelids excised from young and old mice of both sexes.


METHODS
Male and female C57BL/6 mice were euthanized at ages of 3 months or 2 years and their lower eyelids removed, the conjunctival epithelium scrapped off, and the tarsal plate, containing the meibomian glands, dissected from the overlying muscle and lid epidermis. RNA was isolated, enriched, and transcribed into cDNA and processed to generate four non-stranded libraries with distinct bar codes on each adaptor. The libraries were then sequenced and mapped to the mm10 reference genome, and expression results were gathered as reads per length of transcript in kilobases per million mapped reads (RPKM) values. Differential gene expression analyses were performed using CyberT.


RESULTS
Approximately 55 million reads were generated from each library. Expression data indicated that about 15,000 genes were expressed in these tissues. Of the genes that showed more than twofold significant differences in either young or old tissue, 698 were identified as differentially expressed. According to the Gene Ontology (GO) analysis, the cellular, developmental, and metabolic processes were found to be highly represented with Wnt function noted to be altered in the aging mouse.


CONCLUSIONS
The RNA sequencing data identified several signaling pathways, including fibroblast growth factor (FGF) and Wnt that were altered in the meibomian glands of aging mice.
The Gavin Herbert Eye Institute, School of Medicine, University of California, Irvine, CA.
Geraint J
GJ
Parfitt
The Gavin Herbert Eye Institute, School of Medicine, University of California, Irvine, CA.
Donald J
DJ
Brown
The Gavin Herbert Eye Institute, School of Medicine, University of California, Irvine, CA.
James V
JV
Jester
D000375:Aging / Q000502:physiology*; D000818:Animals; D005143:Eyelids / Q000502:physiology*; D005260:Female; D005346:Fibroblast Growth Factors / Q000235:genetics; D015870:Gene Expression / Q000502:physiology*; D020869:Gene Expression Profiling; D007150:Immunohistochemistry; D008297:Male; D008537:Meibomian Glands / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D012313:RNA / Q000235:genetics; D017423:Sequence Analysis, RNA; D051153:Wnt Proteins / Q000235:genetics
D051153:Wnt Proteins; D005346:Fibroblast Growth Factors; D012313:RNA