Interaction of Perfumes with Cytochrome P-450 19

Cytochrome P450 (CYP) enzymes play a key role in the metabolism of foreign compounds and in the biosynthesis and catabolism of endogenous substances, including hormones. The activity of these enzymes can be affected by various xenobiotics, such as pollutants, food constituents, pharmaceuticals, and cosmetic products, which can disrupt the endocrine system by interfering with steroidogenic CYPs. CYP19, also known as aromatase, is a crucial enzyme for testosterone conversion into 17β-estradiol, which is the final step in estrogen biosynthesis. Endocrine disruptors have the potential to inhibit CYP19 activity, leading to an imbalance in estrogen levels in the body. This imbalance can impair reproduction and cause osteoporosis, atherosclerosis, dementia, and some types of cancer. The aim of this study was to assess the effect of commercially available perfumes on testosterone aromatization to 17β-estradiol. For this purpose, we used high-performance liquid chromatography (HPLC) with UV detection and HPLC coupled with mass spectrometry (MS) to examine CYP19 activity with and without perfume. The results showed that all perfumes tested (in a 300-fold dilution) had an inhibitory effect on this enzyme-catalyzed reaction, particularly the Montale® fragrance, ‘Intense Roses Musk’, which decreased 17β-estradiol production by 88% in comparison with the control. Upon exposure to UV light, the inhibitory effect of this perfume did not decrease. But exposure to UV light significantly increased the inhibitory capacity of another perfume with a weak baseline inhibitory effect. To ascertain whether this inhibition was caused by CYP19 interactions with perfumes, we measured the catalytic activity of NADPH:cytochrome P450 oxidoreductase (CYPOR), the CYP reaction partner, with one selected perfume, ‘Intense Roses Musk’ by Montale®, and found no significant CYPOR inhibition. Accordingly, the decrease in testosterone conversion into 17β-estradiol caused by this perfume derives solely from CYP19. Combined, our findings highlight the importance of testing perfumes rather than single ingredients to determine their potential for adverse effects and to ensure consumer safety because their mixtures can interfere with a key enzyme of estrogen biosynthesis.