4′,7-Isoflavandiol (Equol) Enhances Human Dermal Fibroblast Renewal and Has Effects Similar to 17β-Estradiol in Stimulating Collagen and Elastin Expression. Cell Cycle and RT-PCR Analysis without Phenol Red

Abstract

Polyphenols have general health benefits including anti-photoaging influences to counter the negative effects of ultra-violet (UV) rays from solar light (via the generation of reactive oxygen species (ROS) and oxidative stress (OS)), which leads to the stimulation of matrix metalloproteinases (MMPs) that break down collagen and elastin. The changes in elastin and collagen represent major factors in dermal aging along with a decrease in skin fibroblast number and function. The purpose of this study was to determine the influence of a polyphenolic molecule, 4′,7-Isoflavandiol (Equol) at 10 nM on: (1) fibroblast number and function via cell cycle testing (including apoptosis) and collagen protein expression (types I and III) using long-term (eight-week) 3D human fibroblast cultures by intracellular fluorescent-activated cell sorting (FACS) analysis, and (2) quantifying elastin gene expression levels in short-term (four day) cultures using human monolayer fibroblasts by RT-PCR. In both in vitro testing methods, the presence of phenol red (tissue culture indicator) interfered with the parameter results. Therefore, all experiments were performed without phenol red. Using FACS analysis in the long-term 3D cultures exposure to 10 nM of equol for four days significantly increased the percentage of cycling fibroblasts (rejuvenation) above vehicle control (dimethyl sulfoxide (DMSO)) or 17β-estradiol levels, while apoptosis was not altered by any treatment. In addition, in the long-term cultures, collagen levels were significantly increased in the equol and 17β-estradiol treatments above vehicle control values. In short-term cultures, 10 nM of equol or 17β-estradiol significantly increased elastin gene expression levels above vehicle control values. In summary: (a) phenol red may interfere with tissue culture parameter results and (b) the polyphenolic equol compound, derived from plants, may provide protection against photoaging in cosmetic formulations by stimulating collagen, elastin, and enhancing fibroblast renewal.

Factors Influencing Skin Aging and the Important Role of Estrogens and Selective Estrogen Receptor Modulators (SERMs)

“… 98 From in vitro and clinical studies, equol has similar actions to 17β-estradiol by stimulating collagen, elastin and TIMP expression, while inhibiting elastase and MMPs. 10 , 13 , 91 , 99 …”

“…98 From in vitro and clinical studies, equol has similar actions to 17β-estradiol by stimulating collagen, elastin and TIMP expression, while inhibiting elastase and MMPs. 10,13,91,99 For example, in a randomized, single-center 12-week clinical study women that applied a topical equol treatment twice per day displayed significant increases (across eight skin parameters) over baseline values (Figure 5). 10 The significant increases ranged from 52 to over 75% covering skin firmness to hydration (Figure 5).…”

Phytoestrogens (Resveratrol and Equol) for Estrogen-Deficient Skin—Controversies/Misinformation versus Anti-Aging In Vitro and Clinical Evidence via Nutraceutical-Cosmetics

“…How equol works as an anti-aging skin molecule is shown in Figure 9. From multiple investigations, equol (mostly racemic, but some that studied S-equol) showed: (a) stimulation of collagen, elastin and TIMP 1 (Tissue Inhibitor of Matrix Metalloproteinase 1; inhibits the action of MMP 1) [8,109,118,129,135] (remarkably, in one study racemic equol stimulated SIRT 1 gene expression by almost 2-fold over controls [129], (b) inhibited MMPs (1,3 and 9), elastase and the type 1 5α-reductase enzymes [8,109] plus NFkappB and the interleukin inflammatory biomarkers (IL-6, IL-8 and COX-1) in human skin cells [8,109,118,136], (c) inhibition of AP-1 and neoplastic growth via estrogen-related receptor (ERR) gamma (γ) [8,137,138], (d) like resveratrol, equol stimulated Nrf2 [8,109,139], and (e) both R-equol, racemic equol and S-equol binds the potent androgen, 5α-DHT (5α-dihydrotestosterone, the more potent androgen that has negative impacts on skin health) and ERβ for photoprotection [8,31,32,109,140,141]. Particularly, equol's photoprotection appears to be partially due to its antioxidant capacity and is dependent on stimulating the expression of metallothionein [142,143].…”