Application of a Topical Biomimetic Electrical Signaling Technology to Photo-Aging: A Randomized, Double-Blind, Placebo-Controlled Trial of a Galvanic Zinc-Copper Complex
January 2012 | Volume 11 | Issue 1 | Original Article | 30 | Copyright © January 2012
Jeannette Chantalat MS MBA, Elizabeth Bruning BSC LLB, Ying Sun PhD, Jue-Chen Liu PhD
Johnson & Johnson Consumer Products Company, Skillman, NJ
Abstract
Background: The first signs of facial skin photo-aging often occur in the skin of the periorbital area and include sagging, loss of firmness and definition, and sallowness. Epidermal wounds have been shown to alter the trans-epithelial electrical potential creating an electric signal that directs cell migration in epithelial wound healing; this electric field declines sharply with age. A topical galvanic zinc-copper complex, which couples elemental zinc and copper to create a biomimetic electric field, has demonstrated anti-inflammatory activity and extracellular matrix improvement in vitro, including collagen and elastin production.
Objectives: To evaluate the efficacy and tolerability of a galvanic zinc-copper complex on photo-aging parameters in a randomized, double-blind, placebo-controlled clinical trial.
Materials and Methods: In this eight-week study, women (40-65 years) with mild to moderate photo-aging were randomized to use placebo or 1 of 3 galvanic zinc-copper complex compositions (gel and activating moisturizer). Efficacy evaluations included clinical grading, specialized clinical imaging, and subject self-assessments performed at baseline, 15-30 minutes after product application and after 1, 2, 4, and 8 weeks. Tolerability was based on adverse events and clinical grading of irritation. Significance was set at P≤0.05 versus baseline and between treatment groups.
Results: The study was completed by 124 women. Compositions containing the galvanic zinc-copper complex showed statistically significant clinical improvements versus placebo and baseline rapidly (15-30 min) after application and through week 8. Clinical grading showed significant improvement versus placebo in skin radiance and under-eye dark circles 15-30 minutes after first application with continued improvement through week 8, and in overall photo-damage, fine lines, lifted appearance of the eyes, and under-eye wrinkles starting after two weeks and continuing through week 8. Test compositions were well tolerated.
Conclusion: This galvanic zinc-copper complex provided rapid and lasting improvements versus placebo in photo-aged skin, supporting its use in topical anti-aging formulations.
J Drugs Dermatol. 2012;11(1):30-37.
INTRODUCTION
Individuals assess the age and fatigue of others predominantly
by visual observations of the eye region.1 Signs associated
with chronological and photo-aging in the eye area include fine lines and wrinkles, dark circles and bags under the eye, puffiness and laxity in both the upper and lower eyelids, and increasing folds or drooping of the upper eyelids. Topical retinoids are the current standard of care for photo-aged skin but tolerability issues, such as irritation and erythema, sometimes limit their use particularly in the eye area because of the sensitivity
of the periorbital skin.2-4
Recent evidence suggests that the epidermal bioelectric field plays a key role in mediating wound repair5-7 and may be a novel target for treatment of photo-aging.8 The epidermis generates a trans-epithelial potential (TEP) of 20 to 50 mV and disruption in the skin (e.g., a wound) create a low-resistance pathway, resulting in a lateral voltage gradient that stimulates local keratinocyte and dermal fibroblast migration toward the wound.9,10 Results from a recent study11 showed that following a minor wound, the epidermal electric
field in men and women aged 18 to 29 years was 163±59 mV/mm, compared with 78±15 mV/mm in men and women aged 65 to 80 years. Therefore, it has been theorized that reduced wound electric potential in older persons may be a contributing factor to reduced tissue repair and decreased wound healing capacity.
Signals from external electrical stimulation, similar to bioelectric
signals, have been shown to control cell behavior and tissue regeneration.12-14 Some anti-aging products consist of battery-powered skin patches and hand-held electric stimulation
devices that deliver low-level electrical stimulation to the skin; in the past decade, these have included FDA-cleared products
such as Rejuvenique®, FaceMaster®, NuFace®, InterX 5000,
