|Budget Amount *help
¥6,000,000 (Direct Cost : ¥6,000,000)
Fiscal Year 1999 : ¥3,000,000 (Direct Cost : ¥3,000,000)
Fiscal Year 1998 : ¥3,000,000 (Direct Cost : ¥3,000,000)
1) The mRNA expressions of various growth regulatory molecules in 370 single human anagen hair follicles were analyzed by RT-PCR. The mRNAs of FGF- 1, FG F- 2, FGF-5, FGF-7, TGF-α, TGF-βィイD21ィエD2, hepatocyte growth factor(HGF), IGF-I, p53, p21ィイD1wafl/cip1ィエD1, p27ィイD1kip1ィエD1 and high sulfur protein were detected in most or all of the examined hair follicles per target gene. On the other hand, none of the mRNAs of FGF-3, FGF-4, FGF-6, FGF-9 and IGF-II were detected.
2) The sequences of rat high sulfur protein B2E and B2F were determined and characterized.
3) The mRNAs of both p21ィイD1wafl/cip1ィエD1 and p27ィイD1kip1ィエD1 were detected in the anagen hair follicles by RT-PCR, and their localization was clearly demonstrated in the upper half portion of the hair bulb and the cortex by in situ hybridization. The mRNA of both CDK inhibitors, type I hair keratin (Ha 3) and high sulfur protein B2 were expressed at relatively high levels during anagen than during telogen.
4) Using 3' RACE/nested PCR a
nd immunoblotting, we confirmed the expression of HGF activator in both cultured human follicular papilla cells and outer root sheath cells. In an organ culture system, single-chain HGF stimulated hair follicle elongation. Which was partially inhibited by aprotinin, a serine proteinase inhibitor. These results suggest that single-chain HGF secreted from follicular papilla cells is converted to an active heterodimeric form by intrinsic HGF activator and that the resultant active form of HGF stimulates hair growth.
5) The mRNA expressions of various proteinases and their inhibitors in relation to HGF activation in hair growth were examined using animals with a synchronous hair cycle. Total RNAs were extracted from the anterior dorsal skill of rats in different hair cycle stages, and mRNA expressions or the specific genes were compared using semi-quantitative RT-PCR. The mRNAs of HGF. HGF activator, urokinase. PAI-1. Nexin-1, MMP-2 and TIMP- 1 were expressed strongly in anagen tissue and slightly in telogen tissue.
An experiment using antisense nucleotides against certain growth factor receptor to stimulate hair growth and an experiment using a liposome-entrapped HGF to stimulate mouse hair growth are now carried out to provide reproducible results.