Effects of a cosmetic 'anti-ageing' product improves photoaged skin [corrected]

Abstract

Background: Very few over-the-counter cosmetic 'anti-ageing' products have been subjected to a rigorous double-blind, vehicle-controlled trial of efficacy. Previously we have shown that application of a cosmetic 'anti-ageing' product to photoaged skin under occlusion for 12 days can stimulate the deposition of fibrillin-1. This observation infers potential to repair and perhaps clinically improve photoaged skin.

Objective: We examined another similar over-the-counter cosmetic 'anti-ageing' product using both the patch test assay and a 6-month double-blind, randomized controlled trial (RCT), with a further 6-month open phase to assess clinical efficacy in photoaged skin.

Methods: For the patch test, commercially [corrected] available test product and its vehicle were applied occluded for 12-days to photoaged forearm skin (n = 10) prior to biopsy and immunohistochemical assessment of fibrillin-1; all-transretinoic acid (RA) [corrected] was used as a positive control. Sixty photoaged subjects were recruited to the RCT (test product, n = 30 vs. vehicle, n = 30; once daily for 6-months; face & hands) [corrected] with clinical assessments performed at recruitment and following 1-, 3- & 6-months of use [corrected]. Twenty-eight subjects had skin biopsies (dorsal wrist) at baseline and at 6 months of treatment for immunohistochemical assessment of fibrillin-1 (test product, n = 15; vehicle, n = 13). All subjects [corrected] received test product for a further 6-months. Final clinical assessments were performed at the end of this open period; 27 subjects received test product for 12-months [corrected].

Results: In the 12-day patch test assay, we observed significant immunohistological deposition of fibrillin-1 in skin treated by test product and RA as compared to untreated baseline (P = 0.005 and 0.015 respectively). In the clinical RCT, at 6 months, compared to baseline assessment, 43% of subjects on test product had an improvement in facial wrinkles (P = 0.013), whereas only 22% of subjects using vehicle had clinical improvement (P = ns). Between group comparison of test product and vehicle was non-significant (P = 0.10). After 12 months, there was a significant benefit of test product over that projected for vehicle (70% vs. 33% of subjects improving; combined Wilcoxon rank tests, P = 0.026). There was significant deposition of fibrillin-1 in skin treated for 6 months with test product (mean +/- SE; vehicle, 1.84 +/- 0.23; test product, 2.57 +/- 0.19; P = 0.019).

Conclusion: An over-the-counter cosmetic 'anti-ageing' product demonstrated clear benefit over vehicle in fibrillin-1 deposition over a 6-month trial period. There was a corresponding but non-significant trend towards clinical improvement in facial wrinkles. Clinical improvements in the treated group were increased after a further 6-months of use. This study demonstrates that a cosmetic may improve the appearance of wrinkles and further supports the use of fibrillin-1 as a robust biomarker for repair of photoaged dermis.

Fig 1

Fibrillin-rich microfibrils are deposited in test product- and all-trans retinoic acid (RA)-treated human skin in a short-term patch test assay. Representative photomicrographs showing fibrillin-rich microfibrils (arrows) in photoaged extensor forearm following the extended 12-day patch test protocol: (a) baseline; (b) vehicle; (c) test product. (d) The positive control (0·025% RA) was applied for 4 days to avoid harmful side-effects. Original magnification × 400. (e) Quantification of fibrillin-rich microfibrils following the occluded patch test assay with vehicle, test product or the positive control (RA), compared with the baseline. We identified significantly more fibrillin-rich microfibrils with both the test product (**P=0·005) and RA (*P=0·015).

Fig 2

Application of the test product results in clinical improvement in facial wrinkles. (a) Clinical assessment identified a significant improvement (P=0·026) in wrinkle grade following treatment with the test product compared with the vehicle at 12 months, as ascertained by using a Monte Carlo simulation. Standardized photographs of the face of a 56-year-old woman at (b) baseline and (c) after 6 months’ application of the test product show an improvement in periorbital fine lines and wrinkles.

Fig 3

Fibrillin-rich microfibrils were assessed by immunohistochemistry at recruitment (baseline, a) and after treatment with either vehicle (data not shown) or test product (b). (c) Significant deposition of fibrillin-rich microfibrils was observed in the test product-treated skin. *P=0·019.