Estrogenic effects in Dogs & Fish
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.
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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