Forehead wrinkles: a histological and immunohistochemical evaluation

Background: Wrinkles are associated with cutaneous aging especially on sun-exposed skin. Despite they are considered a major topic in cosmetic dermatology, very few reports have studied the specific histological and immunohistochemical changes characteristic for wrinkles.

Aim: The study aims to evaluate the histological and immunohistochemical changes of static forehead wrinkles in relation to surrounding photoaged skin.

Methods: Biopsy specimens were obtained from the forehead wrinkles of 20 volunteers of Glogau's class III-IV wrinkles. Using histological and immunostaining methods coupled with computerized morphometric analysis, measurement of epidermal thickness and quantitative evaluation of total elastin and tropoelastin as well as collagen types I, III, and VII were performed for skin biopsies.

Results: In the wrinkle site, there was statistically significant lower epidermal thickness (P = 0.001), elastin (P < 0.001), tropoelastin (P < 0.001), and collagen VII (P < 0.001) than the surrounding photoaged skin. Meanwhile, there was no significant difference between the wrinkle site and adjacent photoaged skin regarding collagen type I (P = 0.07) or III (P = 0.07).

Conclusion: This study detected some histological and immunohistochemical differences in the wrinkle site when compared to adjacent photoaged skin. This may help in understanding the pathophysiology of facial wrinkling as well as its ideal way of management.