8-Prenyl naringenin is a potent ERα selective phytoestrogen present in hops and beer

The pharmacognosy of Humulus lupulus L. (hops) with an emphasis on estrogenic properties

“…Several hop-containing cosmetic preparations have been patented since that time. It was recently reported that the known estrogenic constituent 8PN, when administered subcutaneously in ethanol solution, has estrogenic activity (as measured by the effect on uterine and vaginal weights), but is 20,000-fold less potent than estradiol (Schaefer et al, 2003). It is noted that Fenselau and Talalay (1973) prepared and assayed (using a modified Allen-Doisy test, s.c. injection) a variety of hop extracts, but all were negative for estrogenic activity.…”

“…It is a potent ligand for the α-estrogen receptor with an IC 50 value in the nanomolar range (Kitaoka et al, 1998), it stimulates the production of alkaline phosphatase in Ishikawa cells (Milligan et al, 1999), and stimulates the growth of estrogen-dependent MCF7 (Kitaoka et al, 1998) breast cancer cells. It was reported that 8PN has a greater affinity for the ERα where it is 70-fold less potent than estradiol than for ERβ, reported as 20,000-fold less potent than estradiol (Schaefer et al, 2003). Kitaoka et al 1998 synthesized racemic 8PN, separated and assayed the enantiomers, and reported that there was no significant difference in ER binding potency between the 2R and 2S forms.…”

Time dependency of uterine effects of naringenin type phytoestrogens in vivo

“…A group of recently described relatively potent phytoestrogens are of the naringenin type (Milligan et al, 1999;Milligan et al, 2002;Zierau et al, 2002). Especially 8-prenylnaringenin (8-PN) from hops, Humulus lupulus (L.) and beer, initially described as 8-isopentenylnaringenin (Kitaoka et al, 1998) has been characterized as an extremely potent phytoestrogen (Kitaoka et al, 1998;Milligan et al, 1999;Schaefer et al, 2003). The estrogenic activity of 8-PN in vitro is the highest of all plant derived estrogens known so far (Matsumura et al, 2005).…”

“…For both naringenins low toxicity and weak cytostatic properties were reported, making them good candidate molecules for further studies (Tokalov et al, 2004). 8-PN has been demonstrated to be a potent ER selective phytoestrogen (Schaefer et al, 2003). For 6-DMAN the selectivity towards the two ER subtyps has not been investigated so far.…”

The study of dependence of the prenyl flavonoids content in the hop dry extract on temperature parameters of its obtaining

“…The results of the pharmacological studies of hop extracts indicate the relationship between estrogenic activity of the objects and the fraction of prenyl flavonoids: xanthohumol (X), desmethylxanthohumol (DMX), isoxanthohumol (IX), 8-prenylnaringenin (8-PN) and 6-prenylnaringenin (6-PN). It has been found that the marked estrogenic activity of the polyphenolic fraction belongs to 8-PN and characterizes this compound as the most powerful pharmacological agent among the known phytoestrogens [7,8,10].The process chain for obtaining APIs of the plant origin consists of different sets of operations performed according to the specific technological modes. Based on thermolabile properties of most substances of the plant origin the development of the technology for obtaining the corresponding APIs requires the study of dependence of the composition at each process stage involving heating of the product.…”