Expression of GSTM4 and GSTT1 in patients with Tinea versicolor, Tinea inguinalis and Tinea pedis infections: a preliminary study

Abstract

Background. Several skin diseases are believed to be associated with oxidative stress. Defence against reactive oxygen species in the skin involves a variety of antioxidant enzymes, including glutathione-S-transferases (GSTs) catalysing the reaction between reduced glutathione, and a variety of exogenously and endogenously derived electrophilic compounds. The mammalian soluble GSTs are divided into five main classes: alpha (A), mu (M), pi (P), theta (T) and zeta (Z). Aim. To investigate the expression of GSTM4 and GSTT1 in lesional and nonlesional skin of patients with dermatophytoses and Tinea versicolor infection. Methods. Expression of GSTM4 and GSTT1 was assessed by immunohistochemistry for dermatophytoses in 15 patients with T. versicolor, 15 patients with Tinea pedis and 8 patients with Tinea inguinalis, and compared with healthy controls (n = 9). After written consent was signed by each participant, punch biopsies were excised from the centre of the lesional skin sites in patients and from the normal skin sites in controls. The relationships between expression of GSTM4 and GSTT1 isoenzymes and fungal infections were also examined. Results. When the normal and infected tissue of these cases were compared according to their staining intensity, GSTM4 expression was found to be stronger in control epithelium than in the epithelium of patients with T. pedis, T. inguinalis or T. versicolor (P < 0.05). By contrast, expression of GSTT1 was stronger in the epithelium of patients infected with any of the three dermatophytes than in control epithelium (P < 0.05). Conclusions. There is a significant relationship between presence of T. versicolor, T. inguinalis and T. pedis and expression of GSTM4 and GSTT1.