Expression and localization of human alcohol and aldehyde dehydrogenase enzymes in skin

Alcohol dehydrogenase (ADH; EC 1.1.1.1) and aldehyde dehydrogenase (AI;DH; EC 1.2.1.3.) are important enzymes involved in the biotransformation of bot h alcohols and aldehydes. Today, six classes of ADH and twelve classes of A LDH have been defined in mammals. Here we report the detection and localisa tion of three classes of ADH and two classes of ALDH in human skin, using W estern blot analysis and immunohistochemistry with class-specific antisera. Western blot analysis of human skin cytosol revealed that class I-III ADH and class 1 and class 3 ALDH enzymes are expressed, constitutively, in thre e different anatomical regions of human skin (foreskin, breast, abdomen). D ensitometric analysis of the immunoreactive bands revealed differential con stitutive expression of these enzymes in foreskin, breast, and abdomen skin . Immunohistochemistry showed the presence of class I ADH and class III ADH enzymes, predominantly in the epidermis with some localised expression in the dermal appendages of human skin. In comparison, staining for class II A DH was more faint in the epidermis with very little dermal expression. Clas s 1 ALDH and class 3 ALDH were predominantly localised to the epidermis wit h minimal, highly localised dermal appendageal expression. These cutaneous ADH and ALDH enzymes may play significant roles in the metabolism of endoge nous or xenobiotic alcohols and aldehydes. (C) 1999 Academic Press.