Enhancing Cytotoxicity of Tamoxifen Using Geranium Oil

Dai Mizuno; Masahiro Kawahara; Keiko Konoha-Mizuno; Kentaro Yamazaki

doi:10.1155/2022/8091339

Enhancing Cytotoxicity of Tamoxifen Using Geranium Oil

Evid Based Complement Alternat Med. 2022 Mar 16:2022:8091339. doi: 10.1155/2022/8091339. eCollection 2022.

Authors

Dai Mizuno¹, Masahiro Kawahara², Keiko Konoha-Mizuno¹, Kentaro Yamazaki¹

Affiliations

¹ Department of Forensic Medicine, Faculty of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata-shi, Yamagata 990-9585, Japan.
² Research Institute of Pharmaceutical Sciences, Faculty of Pharmacy, Musashino University, 1-1-20 Shin-Machi, Nishitokyo-shi, Tokyo 202-8585, Japan.

Abstract

Aromatherapy and plant-based essential oils are widely used as complementary and alternative therapies for various symptoms, including anxiety, mild mood disorders, and cancer-related pain. In a previous study, we developed an in vitro assay using immortalized hypothalamic neuronal cells (GT1-7 cells). In this study, we used this assay to investigate the effects of Geranium oil on the cytotoxicity of the oestrogen receptor (ER) antagonist: tamoxifen (TMX). The results showed that Geranium oil augmented TMX-induced cell death in a dose-dependent manner without directly reducing the viability of GT1-7 cells. Cotreatment with Geranium oil and ER agonist β-estradiol (E2) attenuated the inhibition of GT1-7 cell growth. Moreover, Geranium oil and geraniol, a major constituent of Geranium oil, showed weak agonist activity on ERα and ERβ with geraniol augmenting TMX-induced cell death similar to that observed in Geranium oil. Both compounds impair E2 activity. These data indicate that geraniol is an essential constituent of Geranium oil.