Characterization of glucose transport system in keratinocytes: Insulin andIGF-1 differentially affect specific transporters

Skin is one of the major tissues displaying chronic diabetic complications. We have studied glucose transport following stimulation with insulin and I GF-1 in cultured mouse keratinocytes. In proliferating cells, acute stimula tion with insulin and IGF-1. increased glucose uptake. Insulin translocated glucose transporters 1 and 5, whereas IGF-1 translocated glucose transport ers 2 and 3. With differentiation, glucose transporter 3 expression increas ed and the expression of glucose transporters 1, 2, and 5 decreased. No inc rease in glucose uptake was observed, however, following stimulation with e ither hormone. These results indicate that insulin and IGF-1 differentially regulate glucose uptake as well as expression and translocation of specifi c transporters in skin keratinocytes.