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- Identification of phytoestrogens in the urine of male
dogs.
- Juniewicz PE, Pallante Morell S, Moser A, Ewing LL
- J Steroid Biochem 1988 Dec 31:6 987-94
- Abstract
- It is becoming increasingly apparent that dietary factors may
play a role in the etiology of hormone dependent neoplasias. It
has been hypothesized that estrogens play some role in the etiology
of benign prostatic hyperplasia (BPH) in the canine. The presence
of estrogen receptor binding activity in a fraction of canine
urine purified by high performance liquid chromatography (HPLC)
that did not correspond to estriol, estradiol, estrone or any
of their primary metabolites was observed in the present study.
We used thermospray-mass spectrometry and GC-MS to identify the
phytoestrogens daidzein, equol, formononetin and genistein in
HPLC purified fractions of urine obtained from male beagles. Using
the same techniques we also confirmed the presence of daidzein
and genistein in the commercial diet fed to these same dogs. Using
the immature rat uterine cytosol estrogen receptor assay, relative
binding affinities of 0.08, 1.1, less than 0.01 and 3.9% were
obtained for daidzein, equol, formononetin and genistein, respectively
when compared to estradiol (100%). In conclusion, phytoestrogens
are present in urine of male beagles. Moreover, the commercial
diet fed to these dogs contains isoflavones which can be converted
to equol by intestinal microflora. These results suggest the need
for investigations of phytoestrogens (e.g. equol) excreted into
the urine daily and its relationship to the incidence and severity
of BPH in the dog.
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- The estrogenic activity of certain phytoestrogens in
the Siberian sturgeon Acipenser baeri.
- Pelissero C, Bennetau B, Babin P, Le Menn F, Dunogues J
- J Steroid Biochem Mol Biol 1991 Mar 38:3 293-9
- Abstract
- Various phytoestrogens such as formononetin, daidzein, genistein
and equol were synthesized. Their purity was assessed by various
analytical techniques including melting point determination, thin-layer
chromatography (TLC), infra-red spectra (i.r. spectra), nuclear
magnetic resonance (1H- and 13C-NMR) and gas chromatography coupled
with mass spectrometry (GC-MS). The estrogenic activity of these
compounds, as well as biochanin A and coumestrol, was biologically
tested by the induction of vitellogenin secretion in yearling
sturgeon and compared to the activity of estradiol-17 beta. Pure
daidzein, biochanin A, genistein, equol and coumestrol all had
estrogenic activity as assessed by their induction of hepatic
synthesis of vitellogenin when administrated intraperitoneally
to yearling Siberian sturgeon. Coumestrol seemed to be the most
potent compound, inducing the most vitellogenin secretion with
the lowest dose administered. Formononetin was inactive when administered
by the intraperitoneal route. All the phytoestrogens tested were
considerably less potent than estradiol-17 beta.
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