Investigation of Saint John`s Wort effects on changes in skin parameters after damage caused by the exposure to ultraviolet radiation

Abstract

Cilj istraživanja: Svrha ovog istraživanja bila je utvrditi postojanje zaštitnih učinaka gospine trave na poremećaje funkcije kože izazvane izlaganjem UV zrakama. Ispitanici i metode: Proveden je randomizirani kontrolirani pokus koji se odvijao na Medicinskom fakultetu u Splitu u razdoblju od 1. veljače do 1. svibnja 2019. godine, a koji je obuhvatio 28 zdravih ispitanika bez dijagnosticiranih kožnih bolesti. Ispitivana područja kože bila su na objema podlakticama ispitanika. Korišten je uređaj MPA 6 (Courage+Khazaka, Koln, Njemačka) s tri sonde za mjerenje TEWL (engl. transepidermal waterloss) vrijednosti, vlažnosti kože, eritema te melanina. Doza UV zračenja koja se primjenjivala na podlaktici bila je 3 J/cm². Korištena su dva pripravka od kojih je jedan sadržavao aktivni sastojak (Hypericum perforatum), a drugi je bio placebo. Rezultati: Nisu pronađene statistički značajne razlike u ispitanim parametrima kože (eritem, vlažnost kože, melanin i TEWL) između skupine koja je koristila pripravke gospine trave u odnosu na placebo skupinu. Zaključci: Naše istraživanje pokazalo je da gospina trava nema zaštitnih učinaka na poremećaje funkcije kože izazvane izlaganjem UV zrakama te da je potrebno u budućnosti provesti više istraživanja na ovu temu.Aim of the study: The purpose of this study was to determine the presence of protective effects of Hypericum perforatum on skin function disorders caused by exposure to UV rays. Subjects and Methods: A randomized controlled trial was conducted at the Medical School in Split during the period from 1st of February until 1st of May 2019, which included 28 healthy subjects without diagnosed skin diseases. The examined areas of the skin were on both forearms of the examinees. A MPA 6 (Courage + Khazaka, Koln, Germany) device was used with three probes for measuring the TEWL (transepidermal waterloss) value, skin moisture, erythema and melanin. The UV radiation dose applied to the forearm was 3 J / cm². Two preparations were used, one containing the active ingredient (Hypericum perforatum), the other being the placebo. Results: No statistically significant differences were found in the tested skin parameters (erythema, skin moisture, melanin and TEWL) between group that used Saint John`s Wort formulation in comparison with the placebo group. Conclusions: Our research has shown that Saint John`s Wort has no protective effects on skin function disorders caused by the exposure to UV radiation and that there is a need for further research in the future on this topic