Skin benefits of a myconoside-rich extract from resurrection plant Haberlea rhodopensisby G. Dell’Acqua, K. Schweikert

International Journal of Cosmetic Science

About

Year
2011
DOI
10.1111/j.1468-2494.2011.00692.x
Subject
Colloid and Surface Chemistry / Chemistry (miscellaneous) / Dermatology / Ageing / Drug Discovery / Pharmaceutical Science

Text

Skin benefits of a myconoside-rich extract from resurrection plant

Haberlea rhodopensis

G. Dell’Acqua and K. Schweikert

Induchem AG, Industriestrasse 8a, CH-8604 Volketswil, Switzerland

Received 23 June 2011, Accepted 15 October 2011

Keywords: elasticity, Haberlea, myconoside, oxidation, radiance

Synopsis

Resurrection plant Haberlea rhodopensis develops molecules to survive drought stress. These molecules allow the plant to resurge from a desiccation state. We have extracted a specific fraction from the plant (Haberlea extract) and found it rich, among other molecules, of a caffeoyl phenylethanoid glycoside called myconoside, a molecule extremely abundant in the plant with a potential role in survival. Peroxide-stressed normal human dermal fibroblasts treated with the Haberlea extract, showed increased collagen VI (+822%), collagen XVI (+928%) and elastin (+144%) mRNA synthesis, measured by RT-qPCR. This effect was superior to those obtained with benchmarks retinoic acid and retinol. When used at 3% in human skin biopsies, Haberlea extract protected against

UV-induced dermis oxidation by 100% (P < 0.01), as evidenced by immunohistochemistry. Finally, when tested in human volunteers (n = 20) at 3% in a cream against a placebo, Haberlea extract increased skin elasticity (3· placebo, P < 0.0002) and skin radiance (4· placebo, P < 0.05) after only 15 days of treatment, with the effect sustained after 30 and 60 days of treatment. We demonstrated that by using Haberlea extract (particularly rich in glycoside myconoside), it is possible to strongly stimulate antioxidant skin defences and extracellular matrix protein synthesis. This effect, in turn, will further stimulate skin elasticity and skin radiance significantly in human volunteers. The extract can be suggested for anti-ageing treatments, intended for claims such as protection from oxidation, increased skin elasticity and enhanced skin radiance.

Introduction

Higher plants, in some conditions and in certain phases of their life, can survive desiccation, but this capacity is restricted to seeds and pollen. A class of plants called ‘resurrection’ plants can survive total water loss in their vegetative tissue. In conditions of extreme drought, these plants would enter into a desiccated state and could remain alive for several years. Upon watering, these plants would rehydrate and be able to resume their functions rapidly [1].

Resurrection plants come from different geographical regions, although all are characterized by drought stress during their life.

Among these plants, we have focused our attention and investigated the species Haberlea rhodopensis (Haberlea) from the Gesneriaceae family. This plant, native to the Balkan region, has been cultivated domestically in the Balkans [2] and in Switzerland. This has allowed the possibility to better study its properties without endangering its biotope by picking it in the wild, also considering the slow growth of the plant and the difficulty to repopulate.

In previous studies, we focused on the capacity of resurrection plants to accumulate sugars before the desiccation state. In doing so, the plant protects vital functions from stress, such as the enzymatic apparatus while increasing carbon storage during the dry state [1, 3]. Sugars that accumulate are sucrose, evidenced in all living tissue [3], but also glucose and raffinose [3, 4]. Of interest is also the observation of selective accumulation of trehalose prompting the use of this sugar in transgenic rice to increase drought resistance [5]. Overall data suggest sugar accumulation as one of the main important mechanisms for resurrection plants to survive a desiccation state. These properties were developed by our group in obtaining from Haberlea a special water-soluble extract rich in these sugars for skin care applications [6].

More recently, we have started exploring the Haberlea fraction rich in polyphenols and produced a phytochemical profile [7]. This fraction is extremely interesting as it is also involved in protecting the plant during the desiccation state and helping its recovery.

Studies in resurrection plants such as Myrothamnus flabellifolia have, in fact, evidenced the importance of the antioxidant status [8] and in particular of polyphenol accumulation during the desiccation state to protect membranes against free radical-induced oxidation [9]. The importance of polyphenols in the desiccation/ recovery passage has been further evidenced in studies on the resurrection plant Ramonda serbica, where the state of polyphenol oxidase and several antioxidant molecules have been correlated with the dehydration/hydration process [10, 11]. Finally, and more recently, studies in Haberlea have confirmed that polyphenols protect chloroplast membranes during plant desiccation and recovery.

The lack of polyphenols during desiccation would, in fact, leave the membranes without protection; allowing oxidation damage and preventing photosynthesis to restart when plant recovers [12].

Based on these evidences, we have isolated a specific fraction extremely rich in polyphenols by a proprietary ethanol/water extraction procedure, in particular a caffeoyl phenylethanoid glycoside called myconoside (Fig. 1). Although no scientific publications on the role of myconoside in the plant are available, its particular abundance suggests an important physiological role for this molecule.

Correspondence: Giorgio Dell’Acqua, Induchem AG, Industriestrasse 8a,

CH-8604 Volketswil, Switzerland. Tel.: +41 44 908 4333; fax: +41 44 908 4330; e-mail: giorgio.dellacqua@induchem.com

International Journal of Cosmetic Science, 2012, 34, 132–139 doi: 10.1111/j.1468-2494.2011.00692.x ª 2011 Induchem AG

ICS ª 2011 Society of Cosmetic Scientists and the Socie´te´ Franc¸aise de Cosme´tologie132

We have therefore investigated this fraction (called in this article

Haberlea extract) for its capacity to induce physiological changes in different skin models, in vitro and ex vivo. In particular, after testing its scavenging properties in a biochemical assay, we have investigated the activation of genes for extracellular markers in fibroblasts under oxidative stress condition, and the capacity of the extract to protect the dermis proteins from oxidation in UV-irradiated human skin explants. Finally, we correlated the experimental data with a large clinical study to evaluate the effect of the extract not only on skin elasticity but also on skin radiance, considering the correlation between skin texture and dermis oxidation status with optical properties of the skin [13].