Multidirectional activity of bakuchiol against cellular mechanisms of facial ageing ‐ Experimental evidence for a holistic treatment approach

Abstract

Objective: Skin ageing is a multifactorial process involving formation of reactive oxygen species, consecutive inflammation with reduced epidermal and dermal cell viability and resulting damage to the extracellular matrix. Effective dermocosmetic treatment modalities should ideally address these hallmarks in a holistic approach.Here, we determined the corresponding activity profile of bakuchiol, a plant-derived meroterpene, in an array of in vitro, ex vivo and in vivo studies and compared it to retinol, currently considered as gold standard in topical antiageing cosmetics. Methods:The antioxidative capacity and power of bakuchiol and retinol were analysed by measuring 2,2′-diphenyl-1-picrylhydrazyl (DPPH) reduction via its absorption decay and electron spin resonance spectroscopy, respectively. Effects on prostaglandin E2 (PGE2), macrophage migration inhibitory factor (MIF), fibroblast growth factor 7 (FGF7), collagen type I and VII (COL1A1, COL7A1), fibronectin (FN) levels as well as the metabolization of water-soluble tetrazolium 1 (WST-1) were determined in human dermal fibroblasts. Epidermal regeneration was assessed utilizing an in vitro wound healing model. FN protein levels were analysed ex vivo after treatment with a formulation containing bakuchiol, retinol or vehicle using suction blister fluid. Skin condition improvement was determined in vivo in a split-face comparison study after application of bakuchiol or vehicle. Results:In contrast to retinol, bakuchiol demonstrated high antioxidative efficacy. Levels of PGE2 and MIF were significantly decreased by both bakuchiol and retinol. Bakuchiol but not retinol significantly increased FGF7 protein levels. WST-1 metabolization levels were significantly augmented by bakuchiol and retinol. Bakuchiol and retinol application led to a significant augmentation of COL1A1, COL7A1 and FN protein levels. Wounds supplemented with bakuchiol but not retinol displayed a significant increase in epidermis regeneration.

Preliminary Approaches to Cosmeceuticals Emulsions Based on N-ProlylPalmitoyl Tripeptide-56 Acetat-Bakuchiol Complex Intended to Combat Skin Oxidative Stress

“…The antioxidant properties of bakuchiol were outlined as an important mechanism against photoaging. Thus, its involvement in several antioxidant processes (e.g., oxygen radicals scavenging, inhibition of lipid peroxidation, activation of nuclear factor erythroid 2-related factor 2, a transcription factor involved in the cell resistance to oxidative stress) [ 64 , 65 , 66 ] support bakuchiol’s efficacy in topical skincare treatments against photoaging, as already shown by some clinical investigations [ 35 , 62 ].…”

“…Bakuchiol has already been highlighted as a quenching agent in several in vitro studies. Blumke et al showed that at a concentration of 100 µM, bakuchiol scavenged DPPH radicals to a greater extent than retinol [ 62 ]. At a similar concentration, the meroterpene exhibited 84.6% ABTS radical scavenging activity, a value comparable with that of the positive control resveratrol [ 63 ].…”

Research Progress on Skin Aging and Active Ingredients

“…This revealed that protocatechuic acid has the effect of skin anti-aging. Nature-Based bakuchiol: Natural bakuchiol has a strong antioxidant activity, which can significantly reduce the levels of PGE2 and MIF [ 63 ]. Female subjects (n = 60) with sensitive skin (e.g., eczema, blackheads, and cosmetic intolerance) were selected and they applied cosmetics containing natural bakuchiol according to the needs of the face for 4 weeks.…”

Development of a new chromatographic method for the determination of bakuchiol in cosmetic products

“…Among the many active compounds found in plants, there are terpenoids, which include bakuchiol [1][2][3]-phenol) is partly phenolic and partly terpene, so it is a meroterpene that combines those two structural elements in a single molecule. Bakuchiol has many beneficial properties for living organisms such as anti-aging, anti-pigmentation, anti-acne, anti-cancer, hepatoprotective, cardioprotective, hypoglycemic, hypolipemic, and antidepressant, antioxidant, anti-inflammatory, antiobesity, and antimicrobial activities, moreover it shows the effect of reducing postmenopausal bone loss [4][5][6][7][8][9] . Mainly due to the antioxidant, antimicrobial, emulsifying, and skin-improving properties of bakuchiol, it is widely used in cosmetology and dermatology 1,7,10,11 .…”