Supporting the protective functions of the lower female reproductive tract with tannin-rich botanicals

The lower female reproductive tract (vagina and ectocervix) is inhabited by a unique microbiota, mainly composed of Lactobacilli , which adhere to the epithelium, forming a protective barrier. Vaginal dysbiosis causing inflammatory response of epithelial cells, affects up to 60% of women and significantly increases the risk of STIs and preterm birth. In traditional medicine, tannin-rich botanicals have been used to treat vaginal infections and inflammation. Nevertheless, their efficacy has yet to be evaluated. The study involved the preparation of 70% ethanolic extracts of Lythri herba (LH) and Quercus cortex (QC), followed by their phytochemical analysis using UHPLC-DAD-MS n . Subsequently, the effects of the extracts on the viability and inflammatory response of vaginal epithelial cells were evaluated. Cell viability was assessed using the MTT assay after a 24-hour incubation with extract concentrations ranging from 15.6 to 1000 μg/mL. The extracts did not exert a negative effect up to 50 μg/mL, with IC 50 values of 552.31±59.23 μg/mL for QC and 596.89±61.76 μg/mL for LH. The anti-inflammatory effects were studied on TNF-α-stimulated VK2/E6E7 cells (10 ng/mL). Both extracts significantly inhibited the secretion of chemokine 8, with IC 50 values of 20.32±5.94 μg/mL (QC) and 19.19±7.62 μg/mL (LH). Quercus cortex and Lythri herba extracts have been shown to be safe for vaginal epithelial cells and to exhibit potent anti-inflammatory properties, thus making them promising agents in alleviating symptoms of vaginal dysbiosis. Funding : Project financed by the Ministry of Science and Higher Education, SKN tworzą innowacje grant no. SKN/SP/601586/2024. Publication History Article published online: 05 March 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany