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Lifestyle Medicine in Menopause and Bone Health
Published in Michelle Tollefson, Nancy Eriksen, Neha Pathak, Improving Women's Health Across the Lifespan, 2021
Not all phytoestrogens are safe and beneficial. Hops, used in beer brewing, contains a potent phytoestrogen called 8-prenylnaringenin (8-PN). Because 8-PN binds to both alpha- and beta-estrogen receptors, it provides some relief from menopausal vasomotor symptoms.33–37 However, 8-PN has a much weaker affinity for the beta-receptor than for the alpha-receptor, which is a concern for potential increased breast cancer risk with use of hops-containing supplements and beer consumption.38,39
Herbs with Antidepressant Effects
Published in Scott Mendelson, Herbal Treatment of Major Depression, 2019
The 8-prenylnaringenin found in Humulus lupulus is a potent phytoestrogen.15 In a prospective, randomized, double-blind, placebo-controlled study, extracts of Humulus lupulus standardized to contain 8-prenylnaringenin (100 μg or 250 μg per dose) relieved symptoms in menopausal women. The responses were determined by means of a modified Kupperman index (KI) and a patients’ questionnaire. Unfortunately, specific mood data was not included.16
Menstrual Disorders and Menopause
Published in James M. Rippe, Lifestyle Medicine, 2019
However, not all phytoestrogens are safe and beneficial. Hops, used in beer brewing, contains a potent phytoestrogen called 8-prenylnaringenin or 8-PN. Because 8-PN demonstrates comparable binding activity to both the alpha- and beta-estrogen receptors, it has been shown to provide some relief from menopausal vasomotor symptoms.75–79 However, because 8-PN has a much weaker affinity for the beta-estrogen receptor than for the alpha-, it is often used in herbal breast enhancing supplements, given that alpha receptors are the primary estrogen receptor in the breast. However, this is also of significant concern for the potential increased risk of breast cancer with use of these supplements just as for other hormone therapies.80,81
Moderate Beer Consumption Modifies Tumoral Growth Parameters and Pyrrolidone Carboxypeptidase Type-I and Type-II Specific Activities in the Hypothalamus-Pituitary-Mammary Gland Axis in an Animal Model of Breast Cancer
Published in Nutrition and Cancer, 2021
María Jesús Ramirez-Expósito, José Manuel Martínez-Martos, Vanesa Cantón-Habas, María del Pilar Carrera-González
Beer is one of the most consumed alcoholic beverages, being the third among general drinks. Currently, multiple types of beer exist, differentiated by the ingredients used and the brewing processes performed. However, the addition of hops (Humulus lupulus) improves its flavor and gives it a protective effect derived from its reducing capacity of pH and antibacterial activity (23–26). Moreover, beer also contains phenolic compounds as secondary metabolites of plants which contribute to its color and aroma. These components also show antioxidant properties (27,28). In the last few years, the beneficial effects of beer compounds on human health have received special attention from the scientific community. Not only the antioxidant but also the anti-inflammatory, anticancer, estrogenic, and even antiviral properties associated with beer intake have been described to be associated with these phenolic compounds (29–31). Specifically, xanthohumol seems to exert anticancer chemopreventive activity in the early stages of the carcinogenic process (28,32) in in vitro experiments (33–35). Conversely, compounds like 8-prenylnaringenin (8-PN) have been described as one of the most potent isolated phytoestrogens (36,37). The administration of 8-PN represents a novel therapeutic approach to the treatment of menopausal and post-menopausal symptoms that occur as a consequence of a progressive decline in hormone levels (38), but it could also interfere in hormone-dependent diseases such as breast cancer.
The hop-derived compounds xanthohumol, isoxanthohumol and 8-prenylnaringenin are tight-binding inhibitors of human aldo-keto reductases 1B1 and 1B10
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2018
Jan Moritz Seliger, Livia Misuri, Edmund Maser, Jan Hintzpeter
The female inflorescences of hops (Humulus lupulus) have long been used in traditional Chinese and Ayurvedic medicine mainly to treat sleep disturbances1 and are also known for their antibiotic properties2. Among the secondary plant compounds that occur in the resinous inflorescences of H. lupulus are prenylated chalcones and other flavonoids3. These compounds are well known for their bittering and preserving qualities in the brewing process of beer3,4, as well as for their bioactivity (antibiotic, anti-viral and antioxidant properties)5–7. Recently, the prenylated chalcone xanthohumol (XN) has come into focus of biomedical research, due to its versatile bioactive characteristics8. Since XN is a unique prenylflavonoid occurring in hops, beer is the only noteworthy dietary source for XN in central Europe. In addition to XN, hops inflorescences also contain flavanones like isoxanthohumol (IX) and 8-prenylnaringenin (8-PN)9 (Figure 1), but at 10- to 100-fold lower concentrations than XN. The main metabolic routes for XN, IX and 8-PN have been characterised extensively, both, in vitro by using human and rat liver microsomes 3,10–12 and in vivo, in rat models13,14. XN is subject to spontaneous conversion into IX via intramolecular Michael addition15. IX, in contrast, undergoes an enzymatic O-demethylation via hepatic CYP1A2 to 8-PN, which has been described as the most potent phytoestrogen found in nature5,16. All three substances are currently under investigation due to their anti-diabetic17,18, anti-carcinogenic3,8,19 and antioxidant properties20. Moreover, XN has been shown to have anti-HIV traits21,22.
Dietary natural flavonoids treating cancer by targeting aryl hydrocarbon receptor
Published in Critical Reviews in Toxicology, 2019
Tian Yang, Ya-Long Feng, Lin Chen, Nosratola D. Vaziri, Ying-Yong Zhao
After the above comparative analysis, the author found that the effect of flavonoid-mediated CYP1 induction on physiological functions is very complicated. On the one hand, enhanced CYP1 activity may lead to metabolic activation of pro-carcinogens, production of genotoxic metabolites, and then covalent binding of DNA and causing carcinogenesis. On the other hand, the induction of CYP1s and some other metabolic enzymes such as glutathione S-transferase and UDP-glucuronyltransferase may accelerate the rate of detoxification of xenobiotics (Kalthoff et al. 2017). Perhaps the contribution of dietary flavonoids to the initiation or prevention of cancer depends on the balance between pro-carcinogen activation and detoxification (Bock 2014). In order to further explore more potential natural AhR ligands, researchers tried to reveal why flavonoids are the largest source of AhR ligands. Generally, substrates for AhR are planar aromatic compounds with few bulky substituent groups. That might partly explain the activity of flavonoids, which have similar planar structures as AhR ligands. In addition, some researchers further analyzed the characteristics of dietary flavones as AhR ligands. Jin et al. indicated that a major structural determinant for AhR activation was the number of hydroxyl groups where pentahydroxyflavonoids (with the exception of morin) > hexahydroxyflavonoids > tetra-/trihydroxyflavonoids (Jin et al. 2018). And Wang et al. proposed that the prenylated naringenin derivative exhibited unique activity compared to the parent naringenin. They found that the significant CYP1A1/1B1 induction by 6-prenylnarigenin compared to 8- prenylnarigenin may suggest that the positioning of the prenyl group is important for AhR activation (Wang et al. 2016). But Calvo et al. suggested that the oral bioavailability of 8-prenylnaringenin in healthy women and men was significantly higher than 6-prenylnaringin in a randomized crossover trial (Calvo-Castro, Burkard, et al. 2018). Obviously there are still mysteries still to be discovered.