Danshen enhanced the estrogenic effects of Qing E formula in ovariectomized rats

The objective of this study was to test whether silymarin induces changes indicative of estrogenic effects in gonadal organs of ovariectomized (OVX) rats. Silymarin was administered in two experimental groups of OVX rats (n = 7 + 7) for 30 days at the doses of 25 or 50 mg per animal per day. OVX rats (n = 7) receiving 5 µg of 17b-estradiol (E2) for the last three days before killing and untreated OVX rats (n = 7) were used as the positive and the negative controls, respectively. Uterine and blood samples were collected immediately after killing. Compared with the negative controls, total and normalized uterine weights were significantly higher in the two experimental groups (P < 0.01 and P < 0.05, respectively). Uterotrophic effects of silymarin were also evident from increased heights of the luminal epithelium (P < 0.01) and the endometrium (P < 0.05). The response was dose-independent within the tested range. The strongest uterine response was observed in the OVX rats treated with E2. A highly significant decrease in mean density of estrogen receptor (ERa) immunostaining in the luminal and the glandular endometrial epithelia (P < 0.01) and a stronger ERa immunostaining in stromal cells were observed in the two experimental and the positive control groups. The activities of alkaline and acid phosphatases were significantly increased in the luminal (P < 0.05) and the glandular (P < 0.01) epithelia only in the rats treated with E2. Both silymarin and E2 induced an increase in thyroid hormone concentrations in blood serum. The rises of free T3 and T4 were significant (P < 0.05) in the group receiving 50 mg of silymarin per day. Hepatic oxidative metabolism of steroids was assumed to be another target of the action of silymarin. The mitochondrial cytochrome P450-dependent testosterone hydroxylase activity and the cytochrome P4501A-dependent 7-ethoxyresorufin O-deethylase activity were significantly increased (P < 0.05) in the group receiving 50 mg of silymarin per day and in the E2-treated control group, respectively. However, the modulations of the CYP enzymes played only a minor role in the overall estrogenic effect of silymarin. Histological and functional alterations in the OVX rats treated orally with silymarin for 30 days were consistent with those seen in E2-treated rats and were indicative of estrogenic effects of silymarin.

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Estrogenic Effects of the Herbal Formula, Menoprogen, in Ovariectomized Rats

Biological and Pharmaceutical Bulletin ◽

10.1248/bpb.33.455 ◽

2010 ◽

Vol 33 (3) ◽

pp. 455-460 ◽

Cited By ~ 13

Author(s):

Hong Ma ◽

Mi Hwa Chung ◽

Ye Lu ◽

Tsutomu Nishihara ◽

Masao Hattori

Keyword(s):

Ovariectomized Rats ◽

Herbal Formula ◽

Estrogenic Effects

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Estrogenic effects of the new opioid antagonist naltrexone-estrone azine on pituitary luteinizing hormone secretion in ovariectomized rats

Life Sciences ◽

10.1016/0024-3205(92)90168-o ◽

1992 ◽

Vol 50 (13) ◽

pp. 913-921 ◽

Cited By ~ 2

Author(s):

M.C. Armeanu ◽

J.A.M.J. van Dieten ◽

V.M. Kolb ◽

J. Schoemaker ◽

J. de Koning

Keyword(s):

Luteinizing Hormone ◽

Hormone Secretion ◽

Ovariectomized Rats ◽

Opioid Antagonist ◽

Luteinizing Hormone Secretion ◽

Estrogenic Effects

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Elucidation of Underlying Mechanisms by Which Millettia macrophylla Benth Induces Its Estrogenic Activity

International Scholarly Research Notices ◽

10.1155/2014/763781 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Stéphane Zingue ◽

Chantal Beatrice Magne Nde ◽

Colin Clyne ◽

Dieudonné Njamen

Keyword(s):

Estrogenic Activity ◽

Receptor Expression ◽

Ovariectomized Rats ◽

Human Embryonic Kidney Cells ◽

Ici 182,780 ◽

Beneficial Effects ◽

Estrogenic Effects ◽

Underlying Mechanisms

Millettia macrophylla is used traditionally to treat menopause related symptoms. This plant was shown to exhibit estrogenic effects in vitro on human embryonic kidney cells and in vivo on ovariectomized rats. The present study aimed at elucidating underlying mechanisms by which M. macrophylla induced its estrogenic effects. To accomplish our goal, kidney Hek293T cells transiently transfected with estrogen alpha or beta receptor expression plasmids were cotreated with a pure antiestrogen ICI 182,780 and the dichloromethane or methanol soluble fractions of M. macrophylla. To follow up, we cotreated ovariectomized rats with both extracts and ICI 182,780 for 3 days in the classical uterotrophic assay. Animals were then sacrificed and the uterine wet weight, total protein levels in uteri, uterine, and vaginal epithelial heights, and mammary gland were assessed. In vitro, the results suggested that the induction of the estrogenic activity by M. macrophylla is due to the binding of its secondary metabolites to ERα and ERβ. In vivo, the cotreatment of extracts and ICI 182,780 significantly abrogated the biological responses induced by the extracts alone. Taken together, these results indicate that the active principles of M. macrophylla induce their beneficial effects on menopausal symptoms by activating the ERs.

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