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G L Adessi

Publications and source records attributed to G L Adessi.

At least 37 records · Page 2Linked to original sources
PubMed1994

[Effects of 17 beta-estradiol and growth factors on cell proliferation and c-fos gene expression, in vitro, in endometrial cells in normal growth].

Glandular epithelial cells (GEC) and stromal cells (SC) were isolated from guinea-pig endometrium and cultured separately. After the cells were made quiescent by serum depletion, cell proliferation and c-fos gene expression were investigated. Estradiol-17 beta (E2) alone had no effect on cell proliferation or c-fos gene expression. Cell proliferation was observed in SC and GEC after stimulation with insulin plus EGF and a supplementary effect was obtained when E2 was associated with these factors only in GEC. In GEC, insulin plus EGF had no effect on c-fos expression but an effect was observed when E2 was associated with these factors or with a protein synthesis inhibitor, cycloheximide (Chx) or puromycine. An E2 effect in the presence of Chx was also observed in SC. These data suggest the presence of a labile protein preventing the in vitro estrogenic action in endometrial cells.

Animals↗
PubMed1994

[Regeneration of transplanted human liver: gene expression at the time of graft implantation].

The liver tissue mRNA expression of protooncogenes c-fos, c-myc, c-Ha-ras, c-met and c-erb B1, and TGF alpha and TGF beta genes is sequentially and temporarily increased in the early stages after partial hepatectomy, ischaemia or other mitogenic stimuli. These gene expressions were studied in 38 samples of liver tissue from 24 patients who underwent orthotopic liver transplantation, at different evolution stages. Eleven samples were obtained from surgical liver biopsies before graft implantation at day 0 (Group A), 14 samples from percutaneous liver biopsies during the post-operative period from day 9 to day 48 (Group B) and 13 samples in the long-term follow-up period from day 102 to day 1,382 (Group C). Gene expression was studied using 32P-labeled cDNA and oligonucleotidic probe hybridization in slot blots. A GAPD gene was used as a control gene. All expression values of protooncogenes were related to those of the GAPD gene. After cold ischaema, the relative gene expression (quantity of specific mRNA/quantity of GAPD mRNA ratio) tended to diminish in most cases. The relative expressions of c-fos, c-myc, c-Ha-ras, c-met and TGF alpha gene were correlated at day 0. During and after the liver transplantation, an overexpression of c-fos, c-myc, c-Ha-ras, c-met and TGF alpha was observed in different pathological conditions such as cold ischaemia and conservation injury, acute rejection, and cytomegalovirus infection. In three cases the relative expression values of c-fos, c-myc and c-Ha-ras increased over long-term follow-up without any associated acute pathology. These results suggest the necessity of an intercellular mediation--by means of graft reperfusion--in induction of hepatocyte proliferation and regeneration of the transplanted liver.

Adult↗
PubMed1993

Identification and characterization of an early estrogen-regulated RNA in cultured guinea-pig endometrial cells.

A cDNA library was prepared from quiescent guinea-pig endometrial glandular epithelial cells stimulated for 2 h with estradiol-17 beta (E2) in the presence of cycloheximide. It was screened by differential hybridization for estrogen-regulated sequences. Six recombinants containing E2-regulated sequences were identified. One of them, called gec1 was then characterized by Northern blot hybridization. The gec1 mRNA was 1,800 bases in size. A 2-fold increase in the gec1 mRNA level was achieved at 120 min after E2 treatment. The E2 action on gec1 gene required the presence of cycloheximide. The cloned gec1 cDNA was 1 kb in size. The sequence so far determined did not show similarity with well characterized genes. This is the first report on a cloned cDNA probe of early estrogen-induced mRNA in a primary culture of endometrial epithelial cells.

Animals↗
PubMed1993

Epidermal growth factor and insulin induce the proliferation of guinea pig endometrial stromal cells in serum-free culture, whereas estradiol and progesterone do not.

Guinea pig endometrial stromal cells were cultured in serum-free medium to assess the effects of growth factors and ovarian steroids on cell proliferation. When the cells were made quiescent by serum depletion, [3H]thymidine incorporation was increased by the addition of insulin plus epidermal growth factor (EGF), reaching a peak after 24 h of stimulation. This effect was dose-dependent. Both factors acted synergistically. Estradiol-17 beta (E2), either alone or with various concentrations of growth factors, had no mitogenic effect. Thus, cell proliferation appeared to be estrogen-insensitive, despite a high level of estrogen receptors (19,000 sites per cell). The integrity of these receptors was checked by transfecting cells with a plasmid containing an estrogen-responsive element linked to a CAT gene: E2-induced CAT activity was reduced by the antiestrogen ICI 164,384. Despite the presence of progesterone receptors, the cells, either primed with E2 or not, were not growth-stimulated by progesterone. E2 had no effect on cells cultured in the presence of dextran-coated charcoal-stripped serum. Thus, whatever the culture conditions, stromal cells with functional estrogen receptors were insensitive to the putative mitogenic effects of E2 and progesterone. However, they were highly responsive to the mitogenic effects of insulin and EGF.

Animals↗
PubMed1993

[Restriction polymorphism of C-HA-ras-1 locus in bladder tumors].

The c-Ha-ras-1 polymorphism was studied in 92 bladder tumor samples (newly diagnosed and/or recurrent) obtained from 73 patients and in the paired white blood cells (WBC). A heterozygous state was detected in WBC DNA of 38 patients (52%). The statistical analysis (univariate and multivariate) demonstrated an association between the heterozygous state of the patients and a lymphatic invasion. In patients with a pTa tumor, there was a relation between the heterozygous state and a younger age at diagnosis. A loss of heterozygosity for c-Ha-ras-1 locus was detected in seven out of the 38 informative tumors (18.4%). No significant correlation was observed with the prognostic factors. These results address the relation between the heterozygous genomic state and the risk of lymphatic invasion in the patients with a bladder tumor.

Adult↗
PubMed1992

Purification and characterization of a binding protein related to the Z class of cytosolic proteins in guinea-pig liver cytosol (guinea-pig Z protein).

The purification and characterization of a low-molecular-mass binding protein from female guinea-pig liver cytosol is reported. Its molecular mass (14.4 kDa), amino acid composition, abundance and biological properties identify it as belonging to the Z class of liver cytosolic proteins [Levi, A.J., Gatmaitan, Z. & Arias, I.M. (1969) J. Clin. Invest. 48, 2956-2167]. Among the most important members of this class of proteins are the fatty-acid-binding proteins (FABPs) and the sterol carrier protein2 (SCP2). The guinea-pig Z protein (G-ZP) has some similarities in its amino acid composition and NH2-terminal sequence with those of the rat liver FABP, but its isoelectric point is basic (pI 8.85), like that of SCP2. We also examined its binding affinities for a number of ligands bound by these two proteins. The results show that the purified G-ZP binds dehydroepiandrosterone sulfate, estrone sulfate, oleic acid and cholesterol, but shows no affinity for free steroids such as estrone and DHEA. Thus it can be said that G-ZP has some characteristics of FABPs and some of SCP2 but seems, however, to be different from both these proteins. The purified G-ZP inhibits microsomal DHEA sulfate sulfatase activity in a mixed noncompetitive way. This protein could be involved in the transport and/or metabolism of sulfated steroids.

Amino Acid Sequence↗
PubMed1992

Ultrastructural changes in guinea pig endometrial cells during the estrous cycle.

In the guinea pig, the estrous cycle is characterized by a constant measurable level of plasma progesterone with two peaks: the first one associated with the peak of plasma estradiol-17 beta occurring at proestrus and the second, during diestrus, more pronounced at the time at which the level of estradiol-17 beta is undetectable. The progesterone receptor content is the highest on day 1 and the lowest on day 10 of the estrous cycle, which lasts 16.3 +/- 1.5 days (n = 37; mean +/- SD). There is a positive correlation between the plasma level of estradiol-17 beta and the progesterone receptors detected immunocytochemically in both endometrial epithelial and stromal cells. The general morphology of the endometrium during proestrus and estrus is consistent with an estrogenic stimulation, i.e., a smooth and regular surface of the endometrium and the presence of numerous microvilli on the cell surface. However, a moderate secretory activity also occurs in proestrus and estrus. During postestrus, the glandular cells display an increase in characteristic secretory features which parallels the rise of progesterone in the plasma.

Animals↗
PubMed1992

Serum-free culture of stromal and functionally polarized epithelial cells of guinea-pig endometrium: a potential model for the study of epithelial-stromal paracrine interactions.

Stromal and glandular epithelial (GE) cells were isolated from guinea-pig endometrium and growth to near confluency (6-8 days) in primary culture on plastic surfaces in a serum-supplemented medium (SSM). The stromal cells were subcultured on plastic dishes and maintained for 72 h in SSM. Then SSM was replaced by a chemically defined medium (CDM) and the stromal cells grown to confluency (5-7 days). The GE cells were subcultured in CDM, on a basement membrane matrix (Matrigel) applied to permeable Millicell-PC filters, and grown to confluency (5 days). Homogeneity of the subcultured endometrial cell populations was ascertained immunocytochemically. The filter-cultured GE monolayers were polarized morphologically, and displayed epithelial-specific specialized structures. These monolayers had functional tight junctions as verified by a measurable transepithelial resistance. The subcultured cell populations were distinguished by an analysis of their cellular and secretory proteins after labelling with [35S]-methionine and analysis by polyacrylamide gel electrophoresis. The filter-cultured GE monolayers allowed identification of the proteins released vectorially in the apical or the basal secretory compartment, thus demonstrating the functional polarization of GE cells in this bicameral culture system. Within the defined conditions of this culture system, the paracrine factors released by the two endometrial cell populations as well as the interplay of stromal-epithelial interactions and ovarian hormones could be investigated.

Animals↗
PubMed1992

Progesterone stimulates sulfate uptake in subcultured endometrial epithelial cells.

The effect of progesterone was studied on the sulfate entry in glandular epithelial cells of guinea-pig endometrium subcultured in bicameral chambers on matrix-coated filters in a chemically defined medium. At post-confluency (8 days of subculture), cells were treated with 10 nM estradiol alone or in association with various concentrations of progesterone. Optimal progesterone action was at a 16 h incubation time and a 10 nM hormonal concentration. Progesterone increased in a dose-dependent fashion the sulfate uptake specifically in glandular epithelial cells, preferentially from the basal surface. Progesterone effect on the sulfate uptake occurred only in estradiol-primed epithelial cells and was inhibited by the antiprogestin steroid RU-486. The progesterone-dependent increase in sulfate uptake was inhibited by the inhibitor of anion exchange, 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS). At physiological sulfate concentrations, progesterone essentially induces a high-affinity DIDS-sensitive transport system.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗
PubMed1992

Transfected endometrial cultured cells: a system to study gene-regulation by estrogens.

Glandular epithelial (GE) and stromal cells were isolated from guinea-pig endometrium, cultured and subcultured separately. At the end of subculture, the purity of each cell population was higher than 95% and cells displayed a high level of estrogen receptors. Calcium phosphate transfection conditions were defined using a control plasmid containing the bacterial CAT gene driven by viral promoter and enhancer sequences. Transfection experiments were performed with other plasmids in which CAT gene was linked to different estrogen response elements (EREs) derived from those of vitellogenin genes. CAT activity was significantly increased by estradiol-17 beta treatment only when GE or stromal cells were transfected with plasmids containing EREs previously reported as functional EREs in other cell types. This induction was abolished by ICI 164,384 diethylstilbestrol was as effective as estradiol-17 beta for CAT induction and estradiol-17 alpha was ineffective. Transiently transfected endometrial cells in subculture are a suitable system to study the estrogen effect on gene regulatory elements.

Animals↗
PubMed1992

Expression of c-fos and c-myc genes in uterus and nonreproductive organs during the implantation period in the rat.

The c-fos and c-myc mRNA levels were investigated in the uterus and nonreproductive organs of rats during the implantation period (from day 5 to 7 of pregnancy). They were determined by densitometric analysis of slot blots and the mean values (n = 4) at a defined age of pregnancy were compared with those observed in nonpregnant control rats (NP group). No significant variations of c-fos level were observed in the liver and brain of pregnant rats. In the uterus, the c-fos level decreased, reached a minimum on day 6 (4-fold decrease compared with the NP group), and then increased. The c-fos level significantly increased in the kidney (2- and 2.5-fold on days 6 and 7), and in the lung (2.5-fold on day 7). The c-myc level did not significantly vary in the uterus, liver, and lung. It significantly increased in the kidney (3-fold on day 7) and in the brain (4.1-, 3.8-, and 6-fold, on days 5, 6, and 7). The changes in c-fos and (or) c-myc gene expression in the uterus and nonreproductive organs could be due to sexual steroids and (or) systemic factors from uterine cells or blastocysts.

Animals↗
PubMed1992

Progesterone control of fibronectin secretion in guinea pig endometrium.

Immunohistochemistry with a polyclonal antibody raised against human plasma fibronectin (Fn) was used to determine the localization of Fn in endometrial sections of guinea pig uteri isolated at the first, fourth, sixth, or tenth day of the estrous cycle. Immunoreactive Fn was constantly visualized in the endometrial stroma but absent from the epithelial layer. Fn was detected in the uterine lumen on the first or fourth day of the estrous cycle and was absent from the other sections. To determine the origin of this luminal Fn the ability of subcultured endometrial cells to produce Fn was tested, and the hormonal regulation of Fn secretion was studied. Cells were treated by estradiol alone or in association with progesterone, progesterone alone, or untreated. Whatever the hormonal treatment, stromal cells constantly secreted immunoreactive Fn into the culture medium. In the same way, the amount of Fn synthesized and basally secreted by epithelial cells was not affected by any hormonal treatments. However, Fn was found in the apical secretions of the untreated or estradiol-treated epithelial cells but was undetectable in the apical compartment when the epithelial cells were treated by progesterone alone or in association with estradiol. These results indicate that Fn is constitutively secreted by stromal cells and that subcultured epithelial cells of guinea pig endometrium secrete Fn from both their basal and apical membrane domains. However, the apical secretion of Fn is specifically suppressed by progesterone.

Animals↗
PubMed1991

Establishment of endometrial glandular epithelial cell subculture in a serum-free, hormonally defined medium, on a basement membrane matrix.

Epithelial glands were isolated from guinea-pig endometrium. In order to reduce the requirement for a serum supplement and the contamination by non epithelial cells in primary culture, various coatings of the culture dishes were tested using serum-free Ham's F12 containing defined chemicals including 17 beta-estradiol. While epithelial glands seeded on culture dishes coated with Matrigel, a basement membrane matrix-failed to spread, they formed on poly-D-lysine plus serum-coated dishes, a subconfluent monolayer (5-7 days) enriched in cytokeratin-immunostained cells (78%). Cells from subconfluent primary cultures, obtained on poly-D-lysine plus serum-coated dishes in serum-free hormonally defined medium, were passaged on Matrigel-coated dishes in serum-free hormonally defined medium. These subcultures contained, at confluence (4-5 days), a high percentage (greater than 95%) of cytokeratin-immunostained cells. These monolayers consisted of well-differentiated cells which exhibited ultrastructural features characteristic of endometrial epithelial cells. Moreover, these confluent cells contained 50% immunostained nuclei for progesterone receptors. Progesterone receptor amounts decreased in confluent subcultures treated with progesterone and became undetectable after long-term treatment, suggesting responsiveness of these cells to progesterone. This culture system provides a well-defined model for the study of protein synthesis and secretion by endometrial glandular epithelial cells under hormonal control.

Animals↗
PubMed1991

Progesterone effect on intracellular inorganic sulphate in uterine epithelial cells.

The effect of progesterone on the available intracellular sulphate pool in subcultured glandular epithelial cells from guinea-pig endometrium is reported. Progesterone in concert with 17 beta-estradiol was shown to cause an increase in the available intracellular sulphate pool. The maximum effect was obtained for 10(-8) M and 10(-7) M progesterone. This effect of progesterone on the available intracellular sulphate pool essentially concerned the intracellular inorganic sulphate and was inhibited by the antiprogesterone steroid RU 486 (5 x 10(-7) M). Sulphate incorporation into the endometrial epithelial cells was suppressed by the inhibitor of anion transport diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) and the protein synthesis inhibitor, cycloheximide. These results would suggest that a sulphate transport system may be involved in the accumulation of the intracellular sulphate, stimulated by progesterone. This phenomenon could be an early process in the preparation of the endometrium for implantation.

Animals↗
PubMed1991

Proliferation of guinea-pig uterine epithelial cells in serum-free culture conditions: effect of 17 beta-estradiol, epidermal growth factor and insulin.

The effects of 17 beta-estradiol (E2), epidermal growth factor (EGF) and insulin, alone or in association on guinea-pig uterine epithelial cell proliferation were examined in serum-free culture conditions. Primary cultures of epithelial cells were made quiescent by serum depletion, then incubated in a chemically defined medium. In this medium, insulin increased DNA synthesis but not in a dose-dependent manner for concentrations ranging from 0.2 to 10 micrograms/ml. A significant effect of EGF was found only for the highest concentration tested (100 ng/ml). E2 alone or in the presence of insulin (1 microgram/ml) had no effect whatsoever on the concentration tested (10(-10)-10(-5)M). Insulin (10 micrograms/ml) plus EGF (100 ng/ml) exerted on DNA synthesis and cell proliferation a significant additive effect which was identical to the growth stimulation induced by 10% fetal calf serum. The effects of insulin plus EGF were not modified by the addition of E2. These findings suggest that E2 is not directly mitogenic for uterine epithelial cells in defined culture conditions and that the mitogenic response to optimal concentration of insulin plus EGF is independent of E2.

Animals↗