scholarly journals Effects of vitamin B6 deficiency and repletion on the uptake of steroid hormones into uterus slices and isolated liver cells of rats

1989 ◽  
Vol 61 (3) ◽  
pp. 619-628 ◽  
Author(s):  
David A. Bender ◽  
Kweku Ghartey-Sam ◽  
Amerjit Singh
Keyword(s):  
Hormone Receptors ◽  
Pyridoxal Phosphate ◽  
Steroid Hormone ◽  
Isolated Hepatocytes ◽  
Steroid Hormone Receptors ◽  
Nuclear Accumulation ◽  
Vitamin B ◽  
Receptor Complexes ◽  
Nuclear Binding

1. In vitro, pyridoxal phosphate extracts steroid-hormone receptors from tight nuclear binding (Cidlowski & Thanassi, 1981); in vitamin B6-deficient rats there is increased and prolonged nuclear accumulation of oestradiol in the uterus and testosterone in the prostate, associated with enhanced biological responsiveness of these target tissues to steroid hormone action (Symes et al. 1984; Bowden et al. 1986).2. Slices of uterus from vitamin B6-deficient rats accumulated more [3H]oestradiol than did tissue from repleted animals. Acute repletion with vitamin B6 (0.5–1 h before killing) further increased the uptake of the steroid.3. Isolated hepatocytes from vitamin B6-deficient rats accumulated more [3H]dexamethasone than did cells from repleted animals. Pre-incubation of the hepatocytes with pyridoxal phosphate resulted in a further increase in the uptake of the steroid.4. The results suggest that in addition to the putative role of pyridoxal phosphate in releasing steroid-hormone-receptor complexes from tight nuclear binding (Cidlowski & Thanassi, 1981), vitamin B6 deficiency may also increase the concentration of steroid-hormone receptors or enzymes and other steroid-binding proteins in target tissues.

scholarly journals Regulation of functional steroid receptors and ligand-induced responses in telomerase-immortalized human endometrial epithelial cells

2005 ◽  
Vol 34 (2) ◽  
pp. 517-534 ◽  
Author(s):  
S Hombach-Klonisch ◽  
A Kehlen ◽  
P A Fowler ◽  
B Huppertz ◽  
J F Jugert ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Estrogen Receptor Alpha ◽  
Hormone Receptors ◽  
Steroid Receptors ◽  
Steroid Hormone ◽  
Three Dimensional ◽  
Steroid Hormone Receptors ◽  
Endogenous Estrogen ◽  
Endometrial Epithelial Cells

Information on the regulation of steroid hormone receptors and their distinct functions within the human endometrial epithelium is largely unavailable. We have immortalized human primary endometrial epithelial cells (EECs) isolated from a normal proliferative phase endometrium by stably transfecting the catalytic subunit (hTERT) of the human telomerase complex and cultured these hTERT-EECs now for over 350 population doublings. Active hTERT was detected in hTERT-EECs employing the telomerase repeat amplification assay protocol. hTERT-EECs revealed a polarized, non-invasive epithelial phenotype with apical microvilli and production of a basal lamina when grown on a three-dimensional collagen–fibroblast lattice. Employing atomic force microscopy, living hTERT-EECs were shown to produce extracellular matrix (ECM) components and ECM secretion was modified by estrogen and progesterone (P4). hTERT-EECs expressed inducible and functional endogenous estrogen receptor-alpha (ER-alpha) as demonstrated by estrogen response element reporter assays and induction of P4 receptor (PR). P4 treatment down-regulated PR expression, induced MUC-1 gene activity and resulted in increased ER-beta transcriptional activity. Gene activities of cytokines and their receptors interleukin (IL)-6, leukemia inhibitory factor (LIF), IL-11 and IL-6 receptor (IL6-R), LIF receptor and gp130 relevant to implantation revealed a 17 beta-estradiol (E2)-mediated up-regulation of IL-6 and an E2- and P4-mediated up-regulation of IL6-R in hTERT-EECs. Thus, hTERT-EECs may be regarded as a novel in vitro model to investigate the role of human EECs in steroid hormone-dependent normal physiology and pathologies, including implantation failure, endometriosis and endometrial cancer.

scholarly journals Functional interaction of hybrid response elements with wild-type and mutant steroid hormone receptors.

1991 ◽  
Vol 11 (6) ◽  
pp. 3247-3258 ◽  
Author(s):  
M Truss ◽  
G Chalepakis ◽  
E P Slater ◽  
S Mader ◽  
M Beato
Keyword(s):  
Glucocorticoid Receptor ◽  
Hormone Receptors ◽  
Steroid Hormone ◽  
Steroid Hormone Receptors ◽  
Single Amino Acid ◽  
Wild Type ◽  
Binding Domains ◽  
Responsive Element

Steroid hormone receptors can be divided into two subfamilies according to the structure of their DNA binding domains and the nucleotide sequences which they recognize. The glucocorticoid receptor and the progesterone receptor (PR) recognize an imperfect palindrome (glucocorticoid responsive element/progesterone responsive element [GRE/PRE]) with the conserved half-sequence TGTYCY, whereas the estrogen receptor (ER) recognizes a palindrome (estrogen responsive element) with the half-sequence TGACC. A series of symmetric and asymmetric variants of these hormone responsive elements (HREs) have been tested for receptor binding and for the ability to mediate induction in vivo. High-resolution analysis demonstrates that the overall number and distribution of contacts with the N-7 position of guanines and with the phosphate backbone of various HREs are quite similar for PR and ER. However, PR and glucocorticoid receptor, but not ER, are able to contact the 5'-methyl group of thymines found in position 3 of HREs, as shown by potassium permanganate interference. The ER mutant HE84, which contains a single amino acid exchange, Glu-203 to Gly, in the knuckle of ER, creates a promiscuous ER that is able to bind to GRE/PREs by contacting this thymine. Elements with the sequence GGTCAcagTGTYCT that represent hybrids between an estrogen response element and a GRE/PRE respond to estrogens, glucocorticoids, and progestins in vivo and bind all three wild-type receptors in vitro. These hybrid HREs could serve to confer promiscuous gene regulation.

In Vivo and In Vitro Studies on Steroid Hormone Receptors and Cofactors

2001 ◽  
Author(s):  
Mitsuhiro Kawata ◽  
Mayumi Nishi ◽  
Ken-ichi Matsuda ◽  
Hiroshi Ogawa ◽  
Ikuo Ochiai ◽  
...  
Keyword(s):  
Hormone Receptors ◽  
Steroid Hormone ◽  
In Vitro Studies ◽  
Steroid Hormone Receptors

Antiandrogens as environmental endocrine disruptors¤

1998 ◽  
Vol 10 (1) ◽  
pp. 105 ◽  
Author(s):  
W. R. Kelce ◽  
L. E. Gray ◽  
E. M. Wilson
Keyword(s):  
Androgen Receptor ◽  
Hormone Receptors ◽  
Steroid Hormone ◽  
Sex Differentiation ◽  
Environmental Chemicals ◽  
Steroid Hormone Receptors ◽  
Environmental Endocrine Disruptors ◽  
And Function

Steroid hormone receptors control fundamental events in embryonic development and sex differentiation through their function as ligand-inducible transcription factors. The consequences of disrupting these processes can be especially profound during development due to the crucial role hormones play in controlling transient and irreversible developmental processes. Several environmental chemicals, including metabolites of the fungicide vinclozolin and the pesticide DDT, disrupt male reproductive development and function by inhibiting androgen receptor mediated events. A variety of in vitro and in vivo approaches have been used to determine the molecular basis of environmental antiandrogen toxicity. These chemicals commonly bind androgen receptor with moderate affinity and act as antagonists by inhibiting transcription of androgen dependent genes.

scholarly journals Interaction of oestrogen and progesterone receptors with specific subfractions of laying-hen oviduct chromatin

1984 ◽  
Vol 217 (1) ◽  
pp. 309-316 ◽  
Author(s):  
N Massol ◽  
M C Lebeau ◽  
E E Baulieu
Keyword(s):  
Progesterone Receptor ◽  
Oestrogen Receptor ◽  
Hormone Receptors ◽  
Steroid Hormone ◽  
Progesterone Receptors ◽  
Steroid Hormone Receptors ◽  
Target Tissue ◽  
Low Salt ◽  
High Concentrations

Salt (NaCl)-extracted nuclear oestrogen receptor from hen oviduct was incubated with salt-depleted oviduct chromatin and dialysed to low salt. The oestrogen receptor (re)associated with chromatin to form a 13-14S-sedimenting fraction, as found in ‘native’ chromatin, and saturation of this interaction was obtained for very low receptor concentrations (approx. 0.04 nM). Similarly, purified progesterone receptor from chick oviduct cytosol associated with depleted chromatin to form an 11-12S-sedimenting fraction, as in ‘native’ chromatin; this interaction tended towards saturation for much higher concentrations of progesterone receptor (approx. 8 nM) than that observed for oestrogen receptor. When the two receptors were incubated with depleted chromatin from hen kidney or erythrocytes, their s values were as for oviduct chromatin. However, no saturation of these interactions was seen, even for high concentrations of receptor. Steroid-hormone receptors can therefore bind in vitro to particular subfractions of non-target-tissue chromatin, but with a much lower affinity than to target-tissue chromatin.

Sex Steroid Hormone Receptors and Human Gallbladder Motility in vitro

Digestion ◽  
1990 ◽  
Vol 46 (4) ◽  
pp. 214-219 ◽  
Author(s):  
C. Messa ◽  
M.A. Maselli ◽  
A. Cavallini ◽  
M.L. Caruso ◽  
F. Pezzolla ◽  
...  
Keyword(s):  
Hormone Receptors ◽  
Steroid Hormone ◽  
Steroid Hormone Receptors ◽  
Gallbladder Motility ◽  
Sex Steroid ◽  
Human Gallbladder ◽  
Sex Steroid Hormone
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