Multi-Center, Double-Blind, Vehicle-Controlled Clinical Trial of an Alpha and Beta Defensin-Containing Anti-Aging Skin Care Regimen With Clinical, Histopathologic, Immunohistochemical, Photographic, and Ultrasound Evaluation

April 2018 | Volume 17 | Issue 4 | Original Article | 426 | Copyright © April 2018

Amy Taub MD,a Vivian Bucay MD,b Gregory Keller MD,c Jay Williams PhD,c and Darius Mehregan MDd

aAdvanced Dermatology/Skinfo, Lincolnshire, IL; Northwestern University Medical School, Department of Dermatology, Chicago, IL bBucay Center for Dermatology and Aesthetics, San Antonio, TX cGregory Keller Plastic Surgery, Santa Barbara, CA dWayne State University, Monroe, MI

tumor formation and prepares a favorable microenvironment for cancer cells.35,36 Defensins, however, have not been linked with cancer and some tissues respond to tumor growth by enhanced expression of defensins as a natural protective immune response.37 Studies also show the ability of defensins to suppress tumor growth both in vitro and in vivo.12,38-40 Immunochemical analyses of biopsy specimens in the present study failed to reveal an elevated number of epidermal cells expressing Ki-67, a DNA-binding nuclear protein expressed throughout the cell cycle in proliferating but not dormant cells.41 As a biomarker, Ki-67 has significant prognostic and/or predictive value in cancers such as cutaneous malignant melanoma,42 basal cell carcinoma,43 breast,44 prostate,45 and colorectal.46 Overexpression of Ki-67 is also associated with malignant melanoma,47 and cancers of the brain,48 kidney,49 lung,41,50,51 ovary,52 and thyroid gland.53 Although the findings of the present study do not prove the absence of an association of the full formula with skin cancer, it supports the contention that the full formula does not appear to stimulate carcinogenic properties of cells by 4 factors: 1) the tumor associated Ki-67 antigen was not increased in the study period, 2) defensins have been associated with natural tumor immunity, 3) defensins stimulate new cells that should be mutation-free, and 4) defensins are very specific in their target whereas growth factor mixes have multiple targets, making it more difficult to track their adverse effects. The efficacy of topical retinoids, particularly tretinoin, for the treatment of photoaged skin is well established.54-59 Biopsies of patients treated daily with tretinoin cream (0.001-0.1%) for 3 to 6 months show compaction of the stratum corneum, increased number of granular layers, epidermal thickening, and a reduction in epidermal melanin.55,56 Characterized by erythema, peeling, pruritis, and burning at the treated sites, the “retinoid effect” is also well known.56,60-62 This effect is thought to start by the release of proinflammatory cytokines such as IL-1,TNF-α, IL- 6, and IL-8,63,64 a hypothesis supported by the work of Kim and colleagues61 who showed that retinol-induced inflammation was mediated by changes in the mRNA expression of pro-inflammatory cytokines. Retinoid therapy is also associated with photosensitization, which typically begins early in therapy.60 The present study shows that treatment with the full formula significantly increases epidermal thickness as seen in the histopathological analysis, an observed result that is similar to those seen in topical treatments containing retinol,65 but the full formula achieved this without accompanying inflammation.60,61,66 In addition, the full formula reduced pigmentation and also may have a benefit of increasing the skin’s immunity against cancer. These are all things routinely touted as advantages of retinol and retinoids, yet they were accomplished by the full formula without the adverse effects of peeling, erythema, and diminished compliance that are found with retinol. The full formula products also specifically and significantly reduced visible pores, coarse and fine wrinkles, oiliness, evenness, and pigmentation. Improvements in pores and in both coarse and fine wrinkles were shown clinically by the Griffith scale data, and objectively by three-dimensional imaging. The observations also correlated with the significant improvement of skin’s evenness– a global measurement of skin surface irregularity and roughness depending on the fine or coarse texture of the skin, that was measured using QuantifiCare system. In addition, the significant improvement in pores was confirmed by actual measurement of the pores using the QuantifiCare technology that evaluated pore size, number of pores, and pore depth. Reduction in pigmentation was shown and quantified by the Cortex system, and improvement on skin’s oiliness was measured by QuantifiCare system. Enlarged pores is a chronic and frequent complaint of patients, even in those without acne. It has never had a real histopathologic construct and we don’t know the etiology for these in aging. However, reducing pore size is a unique finding for a skin care product that does not possess any exfoliating capacity. A conundrum of aging is the combination of enlarged pores and dryness, leading often to frustrated patients who are desirous of using retinol due to its anti-aging and pore-reducing properties, but cannot due to the concomitant irritation and xerosis experienced. The full formula product may be the first to offer the unique combination of thickened epidermis, reduced pore size, and reduced wrinkles without an increase in inflammation or irritation and without any reduction of stratum corneum, with its attendant increase is sun sensitivity. In fact, in analyzing the data further we have found that 78% of the participants who had severe conditions in all 3 parameters (enlarged pore size, superficial, and deep wrinkles) at baseline, had significant improvement in all three parameters after treatment. Zero participants (0%) in the PG have demonstrated this finding. Moreover, participants of the FFG in the subset of patients who had biopsies who improved in epidermal thickness also improved in all: pores, superficial and deep wrinkles, and hyperpigmentation, whereas zero participants in the PG demonstrated similar improvement. This observation is consistent with the proposed mechanism of action being the activation of LGR6-positive stem cells, leading to creation of a “new epidermis” (new and young epidermis cells). This should result in the normalization of the entire epidermis and ultimately to global improvement of the skin– exactly what was observed when improvement was analyzed as a complex of skin parameters. These results show that the defensin-containing trio of products offer most of the advantages of time-honored retinols as well as newer but widely used growth-factor containing