Novel Rotational Combination Regimen of Skin Topicals Improves Facial Photoaging: Efficacy Demonstrated in Double-Blinded Clinical Trials and Laboratory Validation

From Frontiers via Jisc Publications RouterHistory: collection 2021, received 2021-06-12, accepted 2021-08-05, epub 2021-09-17Publication status: PublishedTopical antiaging products are often a first-line intervention to counter visible signs of facial photoaging, aiming for sustained cosmetic improvement. However, prolonged application of a single active topical compound was observed clinically to lead to a plateau effect in improving facial photoaging. In view of this, we set out to reduce this effect systematically using a multi-tiered approach with laboratory evidence and clinical trials. The objective of the study was to evaluate the effects of active topical ingredients applied either alone, in combination, or in a rotational manner on modulation of facial photoaging. The study methodology included in vitro, organotypic, and ex vivo skin explants; in vivo biopsy study; as well as clinical trials. We demonstrate for the first time that a pair of known antiaging ingredients applied rotationally, on human dermal fibroblasts, maximized pro-collagen I production. Indeed, rotational treatment with retinol and phytol/glycolic acid (PGA) resulted in better efficacy than application of each active ingredient alone as shown by explants and in vivo biopsy study, with penetration of active ingredients confirmed by Raman spectroscopy. Furthermore, two split-face, randomized, double-blinded clinical trials were conducted, one for 12 months to compare treated vs. untreated and the other for 6 months followed by a 2-month regression to compare treated vs. commercially marketed products. In both studies, rotational regimen showed superior results to its matching comparison as assessed by clinical grading and image analysis of crow's feet wrinkles. In conclusion, rotational regimen using retinol and PGA is effective in treating facial photoaging signs with long-lasting benefits

Assessment of transdermal delivery of topical compounds in skin scarring using a novel combined approach of Raman spectroscopy and HPLC

OBJECTIVE: The goal of any topical formulation is efficient transdermal delivery of its active components. However, delivery of compounds can be problematic with penetration through tough layers of fibrotic dermal scar tissue. APPROACH: We propose a new combined approach using high performance liquid chromatography (HPLC) and Raman spectroscopy (RS) in assessment of penetration of topicals used in scar management. RESULTS: Positive detection of compounds within the treatment topical using both techniques was validated with mass spectrometry. RS detected conformational structural changes; the 1655/1446 cm-1 ratio estimating collagen content significantly decreased (p<0.05) over weeks (W) 4, 12, and 16 compared to Day (D) 0. The amide I band, known to represent collagen and protein in skin, shifted from 1667 cm-1 to 1656 cm-1 which may represent a change from β-sheets in elastin to α-helices in collagen. Confirmatory elastin immunohistochemistry decreased compared to D0, conversely the collagen I/III ratio increased in the same samples by W12 (p<0.05, and p<0.0001 respectively), in keeping with normal scar formation. OCT attenuation coefficient representing collagen deposition was significantly decreased at W4 compared to D0 and increased at W16 (p<0.05). INNOVATION: This study provides a platform for further research on the simultaneous evaluation of the effects of compounds in cutaneous scarring by RS, and a role for RS in the therapeutic evaluation and theranostic management of skin scarring. CONCLUSIONS: RS can provide non-invasive information on the effects of topicals on scar pathogenesis and structural composition, validated by other analytical techniques such as HPLC