Rutin increases critical wavelength of systems containing a single UV filter and with good skin compatibility.
OBJECTIVE
Ultraviolet (UV) radiation is responsible for sunburns, skin cancer, photoaging, and the production of reactive oxygen species (ROS). The awareness on preventing these deleterious effects made the use of anti-UVB formulations an important part of population habits; however, despite the availability of several antioxidants capable of ROS scavenging, the pharmaceutical market lacks products associating UV filters with natural compounds of proven efficacy. Here, we investigated the effect of rutin, a flavonoid with antioxidant activity, associated with UVB filters in dermocosmetic preparations.


METHODS
Formulations were assessed through its antioxidant activity, in vitro photoprotective effectiveness, photostability, and in vivo skin tolerance (hydration, transepidermal water loss, and erythema).


RESULTS
Samples containing rutin were compatible with the human skin and presented a pronounced antioxidant potential, with scavenging activity values 75% higher than the ones containing only UVB filters. Although rutin could not prevent the sunscreens photodegradation post-irradiation, the bioactive compound significantly increased the formulations critical wavelengths, showing a photoprotective gain, especially in the UVA range.


CONCLUSIONS
In conclusion, the absorption in the UVA range, coupled with ROS scavenging potential, proved the positive effect of rutin applied to anti-UVB formulations, making this bioactive compound a promising candidate for photoprotection improvement.
Laboratory of Cosmetology, Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo - SP, Brazil.
D A
DA
Peres
Laboratory of Cosmetology, Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo - SP, Brazil.
C A
CA
de Oliveira
Laboratory of Cosmetology, Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo - SP, Brazil.
M S
MS
da Costa
Laboratory of Cosmetology, Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo - SP, Brazil.
V K
VK
Tokunaga
CBIOS - Research Center for Biosciences and Health Technologies, Lusófona University, Lisbon, Portugal.
J P
JP
Mota
CBIOS - Research Center for Biosciences and Health Technologies, Lusófona University, Lisbon, Portugal.
C
C
Rosado
Laboratory of Cosmetology, Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo - SP, Brazil.
V O
VO
Consiglieri
Laboratory of Cosmetology, Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo - SP, Brazil.
T M
TM
Kaneko
Laboratory of Cosmetology, Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo - SP, Brazil.
M V R
MV
Velasco
Laboratory of Cosmetology, Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo - SP, Brazil.
A R
AR
Baby
D065638:Absorption, Radiation / Q000187:drug effects; D000328:Adult; D000975:Antioxidants / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D004357:Drug Synergism; D005260:Female; D005374:Filtration / Q000379:methods; D006801:Humans; D011837:Radiation-Protective Agents / Q000008:administration & dosage*; D012431:Rutin / Q000008:administration & dosage*; D012867:Skin / Q000187:drug effects / Q000528:radiation effects; D012869:Skin Absorption / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D012879:Skin Physiological Phenomena / Q000187:drug effects* / Q000528:radiation effects*; D013473:Sunscreening Agents / Q000008:administration & dosage*; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014870:Water Loss, Insensible / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects
D000975:Antioxidants; D011837:Radiation-Protective Agents; D013473:Sunscreening Agents; D012431:Rutin
ethylhexyl dimethyl PABA; ethylhexyl methoxycinnamate; flavonoid; octocrylene; photoprotection; photostability