ABSTRACT
BACKGROUND: Psoriasis is a chronic inflammatory skin disease characterized by plaques with inflammation, infiltration, hyper-/parakeratosis and desquamation. Microscopic findings in previous studies have revealed some degree of atrophy of the sebaceous glands in patients with psoriasis vulgaris and psoriatic alopecia. OBJECTIVE: The aim of this study was to investigate possible changes of the sebaceous glands in patients with psoriatic plaques and especially psoriatic alopecia. METHODS: Histological and stereological analyses were performed in skin specimens from involved and healthy-looking skin of 14 patients with psoriasis. Stereology detects and quantifies 3-dimensional structures ex vivo. Furthermore, the differentiation process of sebocytes of another 14 psoriatic patients was examined by immunohistochemistry of involved and uninvolved skin specimens. RESULTS: A significant reduction of the number of sebaceous glands as well as of the volume of individual sebaceous glands was assessed in the lesional compared to the nonlesional psoriatic skin. Moreover, it was likely that sebocytes in psoriatic lesions may not differentiate properly. CONCLUSION: These findings indicate that the sebaceous gland may be a player and not an innocent bystander in the development of psoriatic lesions and especially of psoriatic alopecia.
Subject(s)
Alopecia/etiology , Psoriasis/complications , Sebaceous Glands/pathology , Sebum/metabolism , Skin/pathology , Adult , Aged , Alopecia/diagnosis , Alopecia/metabolism , Biopsy , Female , Humans , Imaging, Three-Dimensional , Immunohistochemistry , Male , Middle Aged , Psoriasis/diagnosis , Psoriasis/metabolism , Sebaceous Glands/metabolism , Severity of Illness Index , Skin/metabolismABSTRACT
The goal of our work has been to investigate the mechanisms of gender-independent human skin ageing and examine the hypothesis of skin being an adequate model of global ageing. For this purpose, whole genome gene profiling was employed in sun-protected skin obtained from European Caucasian young and elderly females (mean age 26.7±4 years [n1â=â7] and 70.75±3.3 years [n2â=â4], respectively) and males (mean age 25.8±5.2 years [n3â=â6] and 76±3.8 years [n4â=â7], respectively) using the Illumina array platform. Confirmation of gene regulation was performed by real-time RT-PCR and immunohistochemistry. 523 genes were significantly regulated in female skin and 401 genes in male skin for the chosen criteria. Of these, 183 genes exhibited increased and 340 decreased expression in females whereas 210 genes showed increased and 191 decreased expression in males with age. In total, 39 genes were common in the target lists of significant regulated genes in males and females. 35 of these genes showed increased (16) or decreased (19) expression independent of gender. Only 4 overlapping genes (OR52N2, F6FR1OP2, TUBAL3 and STK40) showed differential regulation with age. Interestingly, Wnt signalling pathway showed to be significantly downregulated in aged skin with decreased gene and protein expression for males and females, accordingly. In addition, several genes involved in central nervous system (CNS) ageing (f.i. APP, TAU) showed to be expressed in human skin and were significanlty regulated with age. In conclusion, our study provides biomarkers of endogenous human skin ageing in both genders and highlight the role of Wnt signalling in this process. Furthermore, our data give evidence that skin could be used as a good alternative to understand ageing of different tissues such as CNS.
