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.