Phytochemicals/Prenylflavonoids

Prenylflavonoids overlap with other categories of flavonoids.

6-prenylnaringenin edit

8-prenylnaringenin edit

8-Prenylnaringenin (8-PN) or hopein is a prenylflavonoid found in hops. It is the most estrogenic phytoestrogen known,[1] and its effects are similar to estradiol at a fraction of the potency.[2] There is another compound, 8-isopentenylnaringenin, also known as sophoraflavanone B, from sophora flavescens, that could properly be called 8-prenylnaringenin by scientific naming convention.[3]

8-neopentylnaringenin and 8-n-heptylnaringenin are synthetic forms of 8-Prenylnaringenin.[4] Synthesized derivatives of 8-prenylnaringenin are: 7,4′-di-O-methyl-8-prenylnaringenin; 7-O-pentyl-8-prenylnaringenin; 7,4′-Di-O-allyl-8-prenylnaringenin; 7,4′-Di-O-acetyl-8-prenylnaringenin; and 7,4′-Di-O-palmitoyl-8-prenylnaringenin.[5] 6-prenylnaringenin, xanthohumol, isoxanthohumol, and desmethylxanthomul are precursors to 8-prenylnaringenin.[6]

Properties edit

In an in vitro study, 8-Prenylnaringenin and its synthesized derivatives of it demonstrated to have anticancer activity.[5] This prenylflavonoid was shown to preserve bone density, in lab studies.[1]

8-Prenylnaringenin has been demonstrated to reduce hot flashes, in a preclinical study.[1][7] 8-Prenylnaringenin also influences prolactin, and increases other estrogenic responses.[8] This prenylflavonoid interacts with the progesterone receptor,[8] estrogen receptor beta,[9] and estrogen receptor alpha.[2] 8-prenylnaringenin binds to and activates ER-α more times than it does to ER-β in vitro.[10][11]

This prenylflavanoid has drawn interest in the study of hormone replacement therapy, and it is comparable to selective estrogen-receptor modulators.[11][12]

In an in vivo study, 8-prenylnaringenin has activated proliferation of mammary cells.[8] At the concentration found in beer, it is unlikely to have an estrogenic effect in breast tissue.[13] Prenylflavonoids from hops, namely 8-prenylnaringenin, are common in herbal breast enlargement preparations.[2]

Luteinizing hormone (LH) and follicle stimulating hormone (FSH) are reduced by 8-prenylnaringenin.[8] 8-Prenylnaringenin adversely affects male sperm.[14] The role 8-prenylnaringenin plays in fertility requires further research.

References edit

  1. 1.0 1.1 1.2 Keiler; Zierau; Kretzschmar (2013). "Hop Extracts and Hop Substances in Treatment of Menopausal Complaints". Planta Med 2013; 79(07): 576-579 79 (07): 576-567. doi:10.1055/s-0032-1328330. https://www.thieme-connect.com/ejournals/html/10.1055/s-0032-1328330. 
  2. 2.0 2.1 2.2 S. R. Milligan, J. C. Kalita, V. Pocock, V. Van De Kauter, J. F. Stevens, M. L. Deinzer, H. Rong and D. De Keukeleire (December 2000). "The Endocrine Activities of 8-Prenylnaringenin and Related Hop (Humulus lupulus L.) Flavonoids". Journal of Clinical Endocrinology & Metabolism 85 (12): 4912–4915. doi:10.1210/jc.85.12.4912. http://jcem.endojournals.org/content/85/12/4912.full.pdf+html. 
  3. Chadwick; Pauli; Farnsworth (July 1, 2005). "The pharmacognosy of Humulus lupulus L. (hops) with an emphasis on estrogenic properties". Phytomedicine. doi:10.1016/j.phymed.2004.07.006. Retrieved 2013-04-12.
  4. Breen; et al. (2009), The effect of synthetic analogues of the phyto-oestrogen 8-prenylnaringenin on tail skin temperature in a rat hot flush model, The Physiological Society
  5. 5.0 5.1 Anioł, Mirosław (January 7, 2012). "Antiproliferative activity and synthesis of 8-prenylnaringenin derivatives by demethylation of 7-O- and 4′-O-substituted isoxanthohumols". Med Chem Res. doi:10.1007/s00044-011-9967-8. Retrieved 2013-04-07.
  6. Ahmad (2013), Evaluation of Estrogenic Activity of Licorice Species in Comparison with Hops Used in Botanicals for Menopausal Symptoms, PLOS One, doi:10.1371/journal.pone.0067947, PMC 3709979
  7. Bowe, James (November 15, 2012). "The hop phytoestrogen, 8-prenylnaringenin, reverses the ovariectomy-induced rise in skin temperature in an animal model of menopausal hot flushes". Journal of Endocrinology. doi:10.1677/joe.1.06919. Retrieved 2013-04-07.
  8. 8.0 8.1 8.2 8.3 In vivo estrogenic comparisons of Trifolium pratense (red clover) Humulus lupulus (hops), and the pure compounds isoxanthohumol and 8-prenylnaringenin.
  9. Choi, Yongsoo (January 11, 2008). "Development of a screening assay for ligands to the estrogen receptor based on magnetic microparticles and LC-MS". Comb Chem High Throughput Screen. Retrieved 2013-04-07.
  10. Overk (August 2005). "Comparison of the In Vitro Estrogenic Activities of Compounds from Hops (Humulus lupulus) and Red Clover (Trifolium pratense)". J Agric Food Chem 53 ((16)): 6246–6253.. doi:10.1021/jf050448p. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1815392/. 
  11. 11.0 11.1 Rad, Hümpel, Burggraaf (September 1 2006). "Pharmacokinetics and systemic endocrine effects of the phyto-oestrogen 8-prenylnaringenin after single oral doses to postmenopausal women". British Journal of Clinical Pharmacology 62 (3): 288-296. doi:10.1111/j.1365-2125.2006.02656.x. PMC 1885137. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1885137/. 
  12. Bowe (November 2006). "The hop phytoestrogen, 8-prenylnaringenin, reverses the ovariectomy-induced rise in skin temperature in an animal model of menopausal hot flushes". Journal of Endocrinology. doi:10.1677/joe.1.06919. Retrieved 2013-04-08.
  13. Disposition of hop prenylflavonoids in human breast tissue. Bolca S, Li J, Nikolic D, Roche N, Blondeel P, Possemiers S, De Keukeleire D, Bracke M, Heyerick A, van Breemen RB and Depypere H, Mol Nutr Food Res., July 2010, volume 54, Supplement 2, pages 284-294, doi:10.1002/mnfr.200900519, PMID 20486208
  14. "Environmental 'hormones' wreck sperm". BBC News. July 2, 2002. Retrieved 2013-06-26.

Isoxanthohumol edit

Isoxanthohumol can be converted into 8-prenylnaringenin by bacteria in the human intestine.[1]

References edit

Xanthohumol edit

6,8-diprenyleriodictyol edit

Dorsmanin C edit

Dorsmanin F edit