|Budget Amount *help
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2003: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 2002: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 2001: ¥1,300,000 (Direct Cost: ¥1,300,000)
Lipid metabolism and transport in differentiating human keratinocytes were investigated with BCO2PY-lipid(BOD2PY-Ceranide). Only plasma meinbrane was labeled with BOD2PY-lipid 0℃. 30min incubation with BOD2PY-lipid was enough to label the plasma membrane, and its labeling is proportional to BOD2PY-lipid concentration in medium. Although BOD2PY-Ceramide was not metabolized to other lipid at 0℃, it was metabolized to BOD2PY-glucosyl ceramide or BOD2PY-sphingomyelin at 37℃ and these lipids were quantified. After excess BOD2PY-lipid present at the plasma membrane was removed with high concentrated BSA medium, BOD2PY-lipids in the keratinocyte (probably, in Golgi apparatus and/or lamellai-granvles) were observed. If these Bod1py-lipids were secreted into the stratum corneum by exocytosis under some condition, it is possible to recover and maintain the Skin barrier function, because major lipid constituents of the epidermal barrier are transported and stored in these intracellular vesicles. although it was tried whether BOD2PY-lipid exocytosis is accelerated with non Ca^<2+>-, high Ca^<2+>-, epidermal growth factor-, keratinocyte growth factor-, or retinoic acid-containing medium, quantification of the secreted lipids was impossible because of little amount of BOD2PY-lipids in each medium. However, it seemed that much BOD2PY-lipid was present in non Ca^<2+> medium than high Ca^<2+> medium in any condition. Lipids concerned with epidermal permeability barrier may be easily secreted with non Ca^<2+> condition, independent of additional substances. These results indicate that BOD2PY-lipids are very useful to investigate keratinocyte lipid metabolism and transport. BOD2PY-lipid endocytosis and exocytosis studies will lead us to the new treatment of xerosis or asteatotic diseases.