INTRODUCTION
The aging process results in progressive drying of the
skin, changes in the microrelief and pigmentation patterns,
reduced firmness and elasticity, and appearance
of wrinkles.1 In this context, many anti-aging products containing
natural ingredients with antioxidant properties have been
marketed, aiming to improve conditions of the aged skin. In addition,
botanical extracts have been widely used for dry skin.2
This way, more investigation on the mode of action and clinical
studies are required to prove their effects. Among these natural
ingredients, green tea and Ginkgo biloba extracts have been
widely employed in cosmetic formulations.3
Green tea extracts contain four catechin derivatives, predominantly
epicatechin, epigallocatechin, epicatechin gallate, and epicatechin
3-gallate, which have been studied for their antioxidant, anti-inflammatory,
and anticancer properties.4 The green tea polyphenols
included in cosmetic formulations show good skin penetration and
retention. These properties may favor skin performance5 in terms
of inhibition of the acute effects caused by exposure to UVB radiation
and reduction of inflammation, consequently avoiding the
erythema and immunosuppression induced by solar radiation.6
Components of the green tea extract neutralize reactive oxygen
species, thereby preventing lipid peroxidation and photoaging. 6
The use of the Ginkgo biloba extract in anti-aging cosmetics
has been recently proposed because it is rich in flavonoids
(rutin, quercetin, kaempferol), biflavones (bilobetin and
ginkgetin), and terpenoids (ginkgolides, bilobalide), which
are responsible for the antioxidant and anti-inflammatory activities of this extract.5,7,8 Therefore, combination of the antioxidant
properties of the green tea and Ginkgo biloba extracts
in cosmetic formulations could provide great benefits to the
skin.7,9 In addition, due to green tea and Ginkgo biloba extracts
rich composition,10-12 they could also provide extra benefits to
the skin, like moisturizing and protective effects.13,14
Some studies showed that these extracts act on fibroblast
proliferation and production of collagen and extracellular fibronectin.
15 It is also described improvement of skin texture and
appearance observed by dermatologists16 and moisturizing effects
and improvement of skin microrelief.17 However, several
issues concerning the effectiveness of botanical extracts in cosmetic
formulations need to be scientifically clarified.
On the basis of their composition and related data in literature,
it has been proposed that the green tea (Camellia sinensis) and
Ginkgo biloba extracts have potential use in cosmetic formulations
with anti-aging effects. Hence, the efficacy of topical
formulations containing these extracts should be investigated,
in order to assess whether the impact of these formulations on
the human skin under the real conditions of use. This way, the
biophysical techniques have been widely used to evaluate the
clinical efficacy of cosmetic products.17,18
The traditional histopathological and histometric techniques lead
to excellent results and enable accomplishment of a wide range
of studies, ie, analysis of the epithelial tissue, dermis, and cellular
characteristics. However, they are invasive techniques.19,20 In this
