Development of repellent multifunctional cosmetic formulations and in vitro establishment of safety and determination of in vitro, ex vivo, and in vivo efficacy

• Grant number: 24/09469-6
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: May 01, 2025
• End date: October 31, 2028
• Field of knowledge: Health Sciences - Pharmacy
• Principal Investigator: André Rolim Baby
• Grantee: Bruna Santiago de Oliveira Silva
• Host Institution: Faculdade de Ciências Farmacêuticas (FCF). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Mosquitoes are vectors for the transmission of several arboviruses, which cannot be prevented by vaccination, and still don't have specific treatment. With increasing urbanization and climate change, there is a trend of rising infection rates. Aedes aegypti is the primary vector for arboviruses worldwide and can transmit dengue, Zika virus, chikungunya, and yellow fever. The Zika virus poses risks to pregnant women, as it can lead to complications in fetal development, such as microcephaly and congenital malformations. In 2023 the cases surpassed all previous annual cases and spread beyond traditional infection areas. The reinfection by dengue increases the risk of severe dengue form, which can be fatal. The inflammatory process leads to itching and wounds, necessitating the use of anti-inflammatory agents to improve skin condition. To mitigate these problems caused by mosquito bites, repellent formulations are recommended. The most commonly used synthetic repellents worldwide are DEET, IR3535, and icaridin. DEET, widely used since 1957, is the most toxic among these compounds. Icaridin is a new-generation active ingredient with DEET similar effectiveness but with less associated toxicity. IR3535 is the least toxic molecule among the three mentioned earlier, making it suitable for use in children aged 6 months and pregnant women. This investigation will analyze the anti-inflammatory potential of the association of benzophenone-3 and a combination of the polysaccharides trehalose and arabinogalactan, SkinBlitz, in multifunctional repellent cosmetic formulations. 3-benzophenone is a UV filter with absorption in the UVB and UVA regions. Polysaccharides are naturally occurring polymers that perform various biologically important functions, including the prevention of lipid peroxidation and anti-inflammatory action. The analysis will evaluate the properties and capabilities of the multifunctional repellent cosmetic formulations. Safety assessments will be conducted in vitro using the HET CAM method; efficacy will be measured in vitro through antioxidant activity, anti-inflammatory potential, and photoprotective essay. The antilipoperoxidative profile will be determined using the HPLC-TBARS-EVSC protocol in ex vivo samples, as well as the skin penetration of repellents and benzophenone-3 will be evaluated, and the analysis of anti-inflammatory activity and repellent testing will be performed in vivo.