Expression of lipogenic factors galectin-12, resistin, SREBP-1, and SCD in human sebaceous glands and cultured sebocytes.

The transcription factors CCAAT enhancer-binding protein alpha, beta, and delta, and peroxisome proliferator-activated receptor gamma are known to be crucial to the differentiation of adipocytes and are expressed in sebaceous gland cells. As lipogenesis is key to both adipocyte and sebocyte differentiation we hypothesize that sebocytes follow a similar program of differentiation to adipocytes. We have investigated the expression of known adipogenic factors resistin, galectin-12, sterol response-element-binding protein-1 (SREBP-1) and stearoyl-CoA desaturase in the immortalized sebaceous gland cell line SZ95 and whole skin. Reverse transcriptase-PCR analysis showed the expression of galectin-12, resistin, SREBP-1, and stearoyl-CoA desaturase mRNAs in SZ95 sebocytes. Immunoreactivity was observed for galectin-12 and SREBP-1 in the nuclei and resistin in the cytoplasm of basal sebocytes, and stearoyl CoA desaturase in the cytoplasm of basal and luminal sebocytes of human scalp skin. Expression of galectin-12, resistin, and SREBP-1 in SZ95 sebocytes was confirmed by Western blot analysis. These data provide further evidence that pathways of differentiation in adipocytes and sebocytes could be similar and therefore further understanding of sebaceous gland differentiation and lipogenesis and potential therapies for sebaceous gland disorders may be obtained from our knowledge of adipocyte differentiation.