Anti-inflammatory Effects of Topical Hypericum perforatum: A Systematic Review
Authors:   Universidad Francisco Marroquín, Guatemala, Estrada Monica , Chávez-Nomberto Ruth E. ,   Hospital Nacional Edgardo Rebagliati Martins, Perú, Crestani André Saul ,   Pontificia Catholic University of Parana, Brazil, Tsuneto Ana Paula , Awad Camila ,   CEPS-Universidad del Desarrollo, Chile, Takahiro Chone Carlos ,   University of Campinas, Brazil, Kimura Danieli ,   Irmandade Santa Casa de Misericórdia de São Paulo, Brazil, Quiroz Devy ,   Dresden International University, de Azevedo Lopes Erivelton ,   Albert Einstein Israelit Hospital, Brazil, Ibrahim Abdullah Habiba ,   University of Abuja, Nigeria, García Torres Jacob Eli ,   Universidad Nacional Autónoma de México, México, Díaz-Schmidt Joaquín ,   Clínica Alemana de Santiago, Chile, Jales Neto Levi Higino ,   Sao Camilo Hospital, Brazil, Fernando López Luís ,   Pontificia Universidad Católica Madre y Maestra, Dominican Republic, Bazan Maria , Guidetti Matteo ,   Aldo Ravelli Research Center for Neurotechnology and Experimental Neurotherapeutics, University of Milan, Larco-Castilla Piero ,   Universidad Peruana de Ciencias Aplicadas, Peru, Sucre Santiago ,   Universidad Central de Venezuela, Venezuela, Bola-Oyebamiji Sekinah ,   Osun State University, Nigeria, Vizarreta Rosas Jimena ,   Universidad de San Martin de Porres, Peru, Carvalho Alessandra ,   SARAH Network of Rehabilitation Hospitals, Brazil
Published: July 2023

Introduction: Many inflammatory conditions directly impact the skin through different pathways, the understanding of which should be a priority to develop new medications to treat patients suffering from these conditions. Some studies have demonstrated the anti-inflammatory properties of Hypericum perforatum (HP), but no previous systematic reviews have described all the mechanisms by which topical HP may act on inflammation. Therefore, the purpose of this review was to assess the effects of topical HP on inflammatory markers in inflammatory skin conditions or models involving epithelial cells that have been described so far. Methods: The databases PubMed, Scopus, Research4Life (HINARI), and SciELO were used to retrieve experimental and observational studies, from inception to September 25, 2022, reporting the effects of HP on inflammatory markers in inflammatory skin conditions or models involving epithelial cells. We used the following keywords: Hypericum perforatum, H. perforatum, Saint John’s wort, hypericin, hyperforin, inflammation, pro-inflammatory, inflammatory, inflammatory biomarkers, chemokine, prostaglandin, inflammation mediators, TNF, and tumor necrosis factor. Results: From 348 articles screened, 11 were selected based on inclusion and exclusion criteria: two in vitro studies, eight animal studies, and one human pilot trial. A reduction in proliferation and proinflammatory pathways, IL-8 modulation, and a decrease in TNF expression were the main findings reported in the included studies. Discussion: HP has shown promising effects in reducing inflammatory biomarkers in inflammatory skin diseases and experimental models of epithelial cells. Further studies should confirm this herb’s clinical significance and future applications.