Evaluation of the UVB-screening capacity and restorative
effects exerted by farnesol gel on UVB-caused sunburn
Guan Xuan Wu
Han Hsiang Huang
Huoy Rou Chang
Shyh Ming Kuo
Department of Biomedical Engineering,
I-Shou University, Kaohsiung City, Taiwan
Department of Veterinary Medicine,
National Chiayi University, Chiayi City,
Shyh Ming Kuo, Department of Biomedical
Engineering, I-Shou University, Kaohsiung
Ministry of Science and Technology,
Taiwan, Grant Number: MOST 105-2815-
Farnesol, a natural 15-carbon organic compound, has various microbiological and cellular activ-
ities. It has been found to exert apoptosis-inducing effects against carcinoma cells as well as
antiallergic and anti-inflammatory effects in vivo. In the current study, a series of formulations
composed of various concentrations of hydroxypropyl methylcellulose (HPMC) with the addi-
tion of hyaluronan (HA) and xanthan gum (XG) was designed to evaluate the UVB-screening
-eliminating effects of farnesol in normal fibroblasts. Farnesol at 0.005, 0.0075, and
0.01% exhibited significant capacity for H
scavenging; at 0.0025%, it showed insignificant
effects. Under 120-min UVB exposure, screening with plural gel composed of 0.0025% farne-
sol, 0.5% HA, and 0.5% XG containing 1.5% or 2% HPMC retained normal fibroblast viability.
After 60-min exposure to UVB, screening with plural gel composed of farnesol, HA, XG, and
0.5%, 1.0%, 1.5%, or 2% HPMC decreased the ratio of the G1 phase and increased ratio of
the S phase in comparison with the accumulated cell cycle of the normal fibroblasts without
screening. The gel with 2% HPMC displayed the strongest cell cycle-reversal ability. In vivo
histopathological results showed that the prepared plural gels with 0.5% or 2% HPMC and far-
nesol, HA, and XG had greater antiphotoaging and reparative effects against UVB-induced
changes and damage in the skin. In conclusion, the current in vitro and in vivo results demon-
strated that the prepared plural composed of 0.0025% farnesol, 0.5% HA, 0.5% XG, and 2%
HPMC possessed the greatest UVB-screening capacity and the strongest restorative effects on
UVB-induced sunburned skin.
farnesol, gel, reparative effects, sunburn, UVB-screening
Farnesol is a quorum-sensing molecule produced by Candida albi-
cans. It is a natural 15-carbon organic compound that has many
microbiological and cellular effects.
Studies have shown that farne-
sol can cause growth inhibition, apoptosis, or cell death in patho-
genic fungi and bacteria such as Aspergillus spp,
and Staphylococcus spp.
Moreover, farnesol was
found to exert apoptosis-inducing effects against human oral squa-
mous carcinoma cells.
In recent years, it has been shown to pos-
sess antiallergic and anti-inflammatory effects in ovalbumin-
sensitized and -challenged asthmatic mice. IL-2 and IL-10 secreted
by splenocytes were significantly increased as TNF-a/IL-10 ratio and
IL-4 were reduced. These results demonstrated that farnesol can
modulate the cytokine system in vivo.
Skin is the largest organ in
human and animal bodies, and the balance between various cyto-
kines produced by dermal fibroblasts and epidermal keratinocytes in
its paracrine system plays essential roles in connective tissue/extrac-
ellular matrix (ECM) synthesis and wound healing.
Hence, it is
rational that farnesol could modulate the inflammatory responses
and tissue repair in the skin.
The wavelengths of ultraviolet (UV) radiation from the sun are
classified as UVA, UVB, and UVC. UVB has a short wavelength of
290–320 nm. Overexposure of UV radiation to the skin leads to
sunburn, causing tissue injury and pain. UVB can damage the super-
ficial epidermal layer and thus is the main cause of sunburn. Studies
have also showed that UVB is able to alter dermal elastic fibers,
resulting in a reduction in elastic properties and the formation of
2018 Wiley Periodicals, Inc. wileyonlinelibrary.com/journal/tox Environmental Toxicology. 2018;33:488–507.
Received: 25 July 2017
Revised: 2 January 2018
Accepted: 6 January 2018