Expression of transforming growth factor ∼ and fibroblast growth factor 2 in the lens epithelium of Morioka cataract mice

In the Morioka cataract (MCT) mice, lens opacity appears at 6 to 8 weeks of age, and swollen lens fiber is electron-microscopically observed at 3 weeks after birth. The present study was designed to characterize the expression of transforming growth factor (TGF) and fibroblast growth factor 2 (FGF2) in the lens epithelium of the MCT mice. Immunohistochemical analysis showed that the expression of TGF in the lens epithelium of the MCT mice was stronger than that of the wild-type ddY mice at 2 and 4 weeks after birth. The expression of TGF receptors (TGFRI and TGFRII) and FGF2 in the lens epithelium of the MCT mice was stronger than that of the wild-type ddY mice at 4 weeks and weaker than that of the wild-type ddY mice at 15 weeks after birth. Using real time polymerase chain reaction (PCR), quantitative RT-PCR analysis showed that expression of TGF1 and TGF2 mRNA in the lens of 2-week-old MCT mice was significantly higher compared to age-matched wild-type ddY mice. These findings indicate that the lens epithelium of MCT mice has increased expression of TGF before cataract affection and that changes in the expression of FGF2 as well as TGF may contribute to the progression of the cataract in the mice.