Hyaluronan synthase in trabecular meshwork cells
- 1Department of Ophthalmology, Faculty of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan
- 2Tokyo Research Institute, Seikagaku Corporation, 3-1253 Tateno, Higashi-Yamato, Tokyo, Japan
- 3Matrix Biology Group, Ludwig Institute for Cancer Research, Department of Medical Biochemistry and Microbiolgy, Biomedical Center, Box 582, S-75123 Uppsala, Sweden
- 4Department of Ophthalmology, Yamagata University, School of Medicine, 2-2-2 Iidanishi, Yamagata, Japan, 990-9585
- Correspondence to: Hidetoshi Yamashita, MD, Department of Ophthalmology, Yamagata University, School of Medicine, 2-2-2 Iidanishi, Yamagata, Japan, 990-9585; hyama-tky{at}umin.ac.jp
- Accepted 17 June 2002
Abstract
Background/aims: Hyaluronan is present in the trabecular meshwork where it is involved in the pathophysiology of aqueous outflow environment. In this study, the expression and regulation of hyaluronan synthase (HAS), which is the enzyme synthesising hyaluronan, in trabecular meshwork cells were investigated.
Methods: Cultured bovine trabecular meshwork cells (BTMCs) were used. HAS expression in BTMCs was examined by RT-PCR. The effects of transforming growth factor β (TGF-β) and platelet derived growth factor BB (PDGF-BB) on HAS expression in BTMCs were examined by quantitative RT-PCR. The HAS2 expression by TGF-β and PDGF-BB at the protein level was also confirmed immunohistochemically. The production of hyaluronan from BTMCs was detected by high performance liquid chromatography (HPLC).
Results: Three HAS isoforms were expressed in BTMCs at the mRNA level. Among HAS isoforms, only the expression of HAS2 mRNA was increased by the administration of TGF-β or PDGF-BB. HAS2 upregulation by these growth factors was also confirmed at the protein level. Further, hyaluronan production from BTMCs was stimulated by TGF-β or PDGF-BB.
Conclusion: Expression of HAS in trabecular meshwork may maintain the hyaluronan content in the aqueous outflow pathway. Its production is regulated by TGF-β and PDGF-BB. The regulation of the expression of HAS in trabecular meshwork might be useful for modulating the aqueous outflow environment.







