Biomedical subjects

F Miceli

Publications and source records attributed to F Miceli.

At least 19 recordsLinked to original sources

PubMed2001

Stromal-epithelial interactions modulate estrogen responsiveness in normal human endometrium.

The coculture of endometrial epithelial cells (EEC) with stromal cells (ESC) allows achievement of an improved in vitro system for studying interactions between cells via soluble signals. The purpose of this study was to investigate whether 17beta-estradiol and insulin can induce proliferation of EEC through ESC-secreted factors. No evidence of estrogen-induced EEC proliferation has been reported so far in the conventional culture methods. To this end, we used an in vitro bicameral coculture model where human EEC were grown on extracellular matrix-coated inserts applied in dishes containing ESC. Proliferation was assessed by tritiated thymidine incorporation. Homogeneity of endometrial cell populations was ascertained immunocytochemically. 17beta-estradiol did not induce any proliferative effect on EEC cultured alone. Endometrial epithelial cell proliferation was significantly enhanced in EEC/ESC cocultures; moreover, it was further increased by 17beta-estradiol addition. Insulin increased proliferation in EEC cultured alone, but again the effect was more pronounced in EEC/ESC cocultures. Coincubation of 17beta-estradiol and an antibody against insulin-like growth factor I (IGF I) led to neutralization of ESC-mediated EEC proliferation. This work provides evidence that the effect of 17beta-estradiol on human EEC proliferation may be mediated at least in part through ESC-secreted IGF I. We also showed that insulin effect is also partially due to ESC activation.

Adult↗

PubMed2001

Evidence for a functional link between the heme oxygenase-carbon monoxide pathway and corticotropin-releasing hormone release from primary cultures of human trophoblast cells.

The gene expression and synthesis of both constitutive and inducible heme oxygenase (HO) isoforms have been recently described in human placental cells, but the functional role(s) of this biochemical pathway in placental physiology and pathology is still unclear. In the present study, we have investigated whether HO activity is involved in the control of CRH secretion from trophoblast cells. Fluctuations in HO activity were induced in primary cultures of human trophoblast cells using well-known activators and inhibitors of HO, and the subsequent changes in CRH secretion were monitored measuring CRH immunoreactivity released into the incubation medium. It was found that the increase in HO activity induced by hemin or cobalt chloride (CoCl(2)) was associated with parallel significant increases in CRH release. This effect was probably caused by the gaseous HO end-product, carbon monoxide (CO), because it was blocked by the HO inhibitor tin-mesoporphyrin-9, but it was not mimicked by stable HO end-products, biliverdin and bilirubin. We have also investigated whether stimulation of CRH release induced by HO was mediated by the cyclooxygenase (COX) pathway. Indeed, hemin also caused significant increases in PGE2 release in this experimental paradigm. However, CoCl(2), which also enhances CRH release, had no stimulatory effect and actually inhibited PG secretion; moreover, a nonselective COX inhibitor, indomethacin, failed to counteract hemininduced CRH release. Taken collectively, these findings suggested that modulation of CRH secretion by the HO-CO system occurs through a mechanism independent of COX activity.

Carbon Monoxide↗

PubMed2001

Endothelins enhance prostaglandin (PGE(2) and PGF(2alpha)) biosynthesis and release by human luteal cells: evidence of a new paracrine/autocrine regulation of luteal function.

We have previously shown that endothelin-1 (ET-1) is normally found in human luteal cells, where it is able to significantly inhibit both basal and hCG-induced progesterone production. To further expand our comprehension of the possible roles of endothelins (ETs) in luteal physiology, in this study we used primary cultures of luteal cells exposed to graded doses of ET-1 and ET-3; PGF(2alpha) and PGE(2) were assayed in the culture medium to investigate whether ETs also influence cyclooxygenase activity in these cells. We found that both ETs are able to significantly stimulate PGF(2alpha) and PGE(2) release in a dose- and time-dependent manner. ET-1 was always more effective than ET-3. Experiments with two endothelin receptor antagonists (the BQ485 and BQ788 compounds, which block the ET-A and ET-B receptors, respectively) showed that the two endothelins induce PG production through different receptors and signaling pathways. In conclusion, here we demonstrate the ability of ETs to influence PG synthesis and release from human luteal cells. As PGs are deeply involved in corpus luteum activity, and ETs were also able to influence progesterone production, the present new data suggest an interesting interplay among progesterone, PGs, and ETs in the control of corpus luteum physiology.

Antihypertensive Agents↗

PubMed2000

Expression and relationship between endothelin-1 messenger ribonucleic acid (mRNA) and inducible/endothelial nitric oxide synthase mRNA isoforms from normal and preeclamptic placentas.

Preeclampsia is a mainly vascular disease of pregnancy, probably caused by an imbalance between vasodilator and vasoconstrictor agents that results in generalized vasospasm and poor perfusion in many organs. Among these factors, endothelin-1 (ET-1), a potent vasoconstrictor, is highly increased in preeclamptic women, while nitric oxide (NO), a vasodilator of human utero-placental arteries, is reduced in the same patients. The present study was designed to investigate the interactions between ET-1 and the NO system in the feto-placental unit; to this purpose we also examined the messenger ribonucleic acid (mRNA) expression of ET-1, inducible NO synthase (iNOS), and endothelial NOS (eNOS) in human cultured placental trophoblastic cells obtained from preeclamptic (PE) and normotensive (NT) pregnancies. We also studied whether exogenous ET-1 may affect the expression of iNOS and eNOS in human placental trophoblastic cells. Interestingly, by Northern blot analysis we observed an increased ET-1 mRNA expression level in PE trophoblastic cells compared to NT trophoblastic cells. Furthermore, exogenous ET-1 (10(-7) mol/L) was able to up-regulate its own mRNA expression in both NT and PE trophoblastic cells. iNOS and eNOS mRNA expression was then detected, by semiquantitative PCR, in both NT and PE trophoblastic cells. PE trophoblastic cells expressed lower iNOS mRNA levels compared with NT pregnancies. On the contrary, eNOS mRNA expression was higher in PE trophoblastic cells than in NT cells. Moreover, in the presence of ET-1 we observed a decrease in iNOS and an increase in eNOS mRNA expression levels in both NT and PE trophoblastic cells compared with the respective untreated cells. In conclusion, we demonstrate that ET-1 expression is increased in PE cells, whereas iNOS, which represents the main source of NO synthesis, is decreased; conversely, eNOS expression is increased. Finally, ET-1 is able to influence its own as well as NOS isoform expression in normal and PE trophoblastic cultured cells. These findings suggest the existence of a functional relationships between ET(s) and NOS isoforms that could constitute the biological mechanism leading to the reduced placental blood flow and increased resistance to flow in the feto-maternal circulation, which are characteristic of the pathophysiology of preeclampsia.

Adult↗

PubMed1999

Effect of anticardiolipin antibodies on prolactin and insulin-like growth factor binding protein-1 production by human decidual cells.

PROBLEM: The effect of anticardiolipin antibodies (ACAs) on basal- and growth factor-stimulated prolactin and insulin-like growth factor (IGF) binding protein (BP)-1 production by cultured human decidual cells was investigated. METHOD OF THE STUDY: Decidual cells were cultured for 24, 48, or 96 hr in medium supplemented with 5% ACA-containing or 5% control serum and increasing concentrations of insulin (1-10 micrograms/mL) or IGF-1 (10-100 ng/mL). RESULTS: No significant increase in prolactin production was observed after addition of increasing doses of insulin and IGF-I in the presence of ACA-containing serum, while a dose-dependent stimulation was seen with control serum. Time-dependent prolactin accumulation was also reduced when cells were cultured in the former conditions. IGF BP-1 release was not affected by insulin and IGF-I in the presence of both sera. However, lower IGF BP-1 levels and a less pronounced time-dependent accumulation were observed in the presence of ACA-positive serum. CONCLUSIONS: Our data suggest that ACAs affect cellular transduction mechanisms regulating critical events, such as decidual cell differentiation. These cellular dysfunctions might be relevant in the induction of some obstetric disorders typical of this syndrome.

Antibodies, Anticardiolipin↗

PubMed1999

Paracrine regulation of insulin-like growth factor I (IGF-I) an IGF-II on prostaglandins F2alpha and E2 synthesis by human corpus luteum in vitro: a possible balance of luteotropic and luteolytic effects.

The existence of a complete intraovarian insulin-like growth factor (IGF) system replete with ligands, receptors, and binding proteins has been demonstrated as well as the ability of IGF-I to positively affect steroidogenesis in human granulosa cells. Furthermore, we recently showed that IGF-I and IGF-II stimulate progesterone secretion by human luteal cells. As the PGs, PGE2 and PGF2alpha, are classically known to have luteotropic and luteolytic effects, we wanted to determine whether the IGFs could affect the human luteal phase by influencing the PG system. For this reason, human luteal cells were cultured for different times (12, 24, and 48 h) with IGF-I, IGF-II (10-100 ng/mL), and GH (100 ng/mL), and both PGs were assayed in the medium culture. We found that both IGF-I and IGF-II were able to stimulate PGE2 synthesis in a time- and dose-dependent way, whereas they both inhibited PGF2alpha production. GH, too, significantly reduced PGF2alpha synthesis; this effect was IGF-I mediated because it was reverted by increasing dilutions of an anti-IGF-I antibody. On the contrary, no GH effect was observed on PGE2 production. In conclusion, based on these data and on our previous results, we speculate that IGFs could influence luteal steroidogenesis through PG system.

Adult↗

PubMed1999

Human umbilical vein endothelial cells: a new source and potential target for corticotropin-releasing factor.

Corticotropin-releasing factor (CRF) plays a key role in the modulation of fetal-placental unit function during human pregnancy. CRF has a potent vasoactive action on fetal-placental circulation. As products secreted from endothelial cells affect vascular wall reactivity, we investigated whether cultured human umbilical vein endothelial cells (HUVEC) may represent a source and a target for CRF. With RT-PCR we showed that HUVEC express CRF and CRF receptor type 2 messenger ribonucleic acids. Cultured HUVEC also released CRF peptide in a time-dependent way, and the CRF release was differently regulated by various molecules. Dexamethasone decreased CRF release, whereas progesterone and 17beta-estradiol markedly increased it. Forskolin and PGF2alpha were potent stimulators of CRF release from HUVEC. Among the peptides, CRF secretion was stimulated by interleukin-1beta and by endothelin-1. Our study shows for the first time that HUVEC express CRF messenger ribonucleic acid and peptide as well as the CRF R2 gene, and that CRF release is differentially regulated by several distinct molecules. We here propose that CRF has a role in the regulation of the fetal-placental circulation.

Cells, Cultured↗

PubMed1998

Endothelin-1 inhibits basal and human chorionic gonadotrophin-stimulated progesterone production.

Endothelin-1 (ET-1) is a peptide classically produced by endothelial cells and known for its powerful vasoconstrictor activity. However, recent data suggest an involvement of ET-1 also in reproductive function. This study was designed to examine the possible presence and role of ET-1 in human luteal cells. Purified luteal cells were incubated for different times with ET-1 (10(-9)-10(-6) M) or ET-3 (10(-9)-10(-6)) alone or associated with human chorionic gonadotrophin (HCG) (100 ng/ml). Both basal and HCG-induced progesterone production were significantly reduced by ET-1 at all examined times whereas preincubation of luteal cells with BQ485 (10(-9)-10(-6) M), an ET-A receptor antagonist, prevented the inhibitory effect of ET-1. Conversely, no effect on progesterone synthesis was observed when ET-3 was added to the cultures. Luteal cells were then incubated for 24 h with phorbol 12-myristate-13 acetate (PMA) (100 ng/ml), an activator of protein kinase C. Inhibition of progesterone synthesis by PMA was similar to that induced by ET-1 alone. This study demonstrates that ET-1 negatively affects, at physiological concentrations, basal and HCG-induced progesterone synthesis. These effects seem to be exerted through the ET-A receptors and the protein kinase C pathway. Conversely, ET-3 was not able to influence human luteal steroidogenesis.

Cells, Cultured↗

PubMed1998

Endothelin-1: expression and role in human corpus luteum.

PROBLEM: Several recent data suggest an involvement of endothelin (ET)-1, a powerful vasoconstrictor peptide, in reproductive function. This study was designed to investigate the presence and role of ET-1 in human corpus luteum. METHOD OF STUDY: Purified luteal cells were incubated for different times with ET-1 or ET-3 alone or associated with human chorionic gonadotropin. In another set of experiments cells were treated with ET-1 and BQ485, an ET-A receptor antagonist, or with phorbol 12-myristate-13 acetate (PMA), an activator of protein kinase C. RESULTS: ET-1 reduced both basal and human chorionic gonadotropin-induced progesterone production at all examined times, similarly PMA inhibited basal progesterone synthesis. BQ485 prevented the inhibitory effect of ET-1, while no effect was observed with ET-3. Finally, ET-1 mRNA was detected in the luteal cells. CONCLUSION: ET-1 is expressed by human luteal cells and reduces basal and human chorionic gonadotropin-induced progesterone synthesis through the ET-A receptors and the protein kinase C pathway. Conversely, ET-3 does not affect luteal steroidogenesis.

Adult↗

PubMed1997

Control of human luteal steroidogenesis: role of growth hormone-releasing hormone, vasoactive intestinal peptide, and pituitary adenylate cyclase-activating peptide.

OBJECTIVE: To examine the possible effect of growth hormone-releasing hormone (GHRH), vasoactive intestinal peptide, and pituitary adenylate cyclase-activating peptide on basal and hCG-stimulated P production by human luteal cells. DESIGN: Cultures of human luteal cells from the early and midluteal phase. SETTING: All corpora lutea were obtained from the Obstetrics and Gynecology Department of the Università Cattolica, a public care center. PATIENT(S): Ten nonpregnant women between 35 and 47 years of age underwent surgery for various nonendocrine disorders, such as leiomyomatosis. INTERVENTION(S): Corpora lutea were obtained at the time of hysterectomy. MAIN OUTCOME MEASURE(S): Luteal cells were incubated with GHRH, vasoactive intestinal peptide, and pituitary adenylate cyclase-activating peptide with or without hCG at different concentrations. RESULT(S): Pituitary adenylate cyclase-activating peptide stimulated P production in a dose- and time-dependent manner, whereas GHRH and vasoactive intestinal peptide did not affect luteal steroidogenesis. None of the three peptides were found to synergize with hCG. CONCLUSION(S): Pituitary adenylate cyclase-activating peptide can influence human luteal steroidogenesis.

Adult↗

PubMed1997

Effect of pituitary adenylate cyclase-activating peptide on meiotic maturation in follicle-enclosed, cumulus-enclosed, and denuded rat oocytes.

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a novel bioactive peptide isolated from ovine hypothalamus. Recently, its presence and action have been demonstrated also in peripheral tissues such as testis and ovary. On the basis of sequence similarity, PACAP is included in the vasoactive intestinal peptide (VIP)/glucagon/secretin/growth hormone-releasing factor (GRF) family of neuropeptides. Because both VIP and GRF stimulate oocyte maturation in the rat ovary, we wanted to evaluate whether PACAP also could influence this process. Granulosa cells and follicle-enclosed, cumulus-enclosed, and denuded oocytes were obtained from immature eCG-treated rats. The addition of PACAP-38 significantly accelerated meiotic maturation in follicle- and cumulus-enclosed oocytes from treated rats and in follicle enclosed-oocytes from immature untreated rats, while VIP was effective only on follicle-enclosed oocytes. Interestingly, when used on denuded oocytes, PACAP was able to directly affect the meiotic process. In fact, the neuropeptide delayed oocyte maturation by maintaining elevated levels of intracellular cAMP. Our results clearly demonstrate an involvement of PACAP in oocyte meiotic maturation. Furthermore, for the first time, a direct effect of a peptide on the oocytes has been shown. Moreover, the differences in the action of PACAP and VIP on granulosa cells and oocytes suggest the presence of PACAP type I receptors on both cell types. Our results, along with the data demonstrating the presence of the peptide in the ovary, strongly suggest a potential relevance of PACAP in ovarian physiology.

Animals↗

PubMed1996

Growth hormone stimulates androsterone synthesis by rat theca-interstitial cells.

The aim of this study was to assess the possible role of growth hormone (GH) on androsterone synthesis. This effect was analyzed in theca-interstitial cells obtained from immature female rats. The addition of GH to the cultures significantly stimulated androsterone (A) synthesis in a dose- and time-dependent way and this effect was not due to a cellular number increase. When added to the hCG cultures, GH significantly enhanced androgen production even though it did not synergyze with the chorionic gonadotropin. The addition of antibodies anti-IGF-I to the GH cultures did not modify the growth hormone effect suggesting that GH probably does not require IGF-I to achieve its effect on A production. Finally, no effect of GH on cAMP levels were observed in the cultures at the end of the treatment. Our results demonstrate that GH is able to significantly induce A synthesis by rat theca-interstitial cells. Since the presence of GH and its receptors in the ovary is now well established the present data strongly suggest a potential relevance of GH in reproductive biology.

Androsterone↗

PubMed1996

Insulin-like growth factor (IGF)-I and IGF-II stimulate progesterone production by human luteal cells: role of IGF-I as mediator of growth hormone action.

OBJECTIVE: To examine the possible direct effect of insulin-like growth factor (IGF)-I and IGF-II on basal and hCG-stimulated P production by cultured human luteal cells. The possible role of IGF-I as mediator of GH action on luteal steroidogenesis also was investigated. DESIGN: Cultures of human luteal cells from early and midluteal phase. SETTING: All corpora lutea were obtained from the Obstetrics and Gynecology Department of the Universita Cattolica, a public care center. PATIENTS: Eight nonpregnant women between 35 and 47 years of age underwent surgery for various nonendocrine disorders such as leiomyomatosis. INTERVENTIONS: Corpora lutea were obtained at the time of hysterectomy. MAIN OUTCOME MEASURES: Luteal cells were incubated with IGF-I or IGF-II with or without hCG at different concentrations. Growth hormone also was used alone and with an anti-IGF-I-antibody. RESULTS: We found that IGF-I and IGF-II were able to stimulate directly the P production at all used concentrations and that both of them significantly amplified the steroidogenic hCG effect. Finally, IGF-I was shown to mediate the positive GH action on P synthesis.

Adult↗

PubMed1995

Growth hormone-releasing factor stimulates meiotic maturation in follicle- and cumulus-enclosed rat oocyte.

This study was designed in order to assess the possible role of growth hormone-releasing factor (GRF) on oocyte maturation. This effect was analyzed in follicle-enclosed, cumulus-enclosed and denuded oocytes obtained from immature pregnant mare's serum gonadotropin-treated rats. The addition of GRF to the cultures significantly accelerated maturation in follicle- and cumulus-enclosed oocytes while no effect was seen on denuded oocytes. Also, the neuropeptide was able to induce maturation in follicle-enclosed oocytes obtained from immature untreated rats. The GRF action was probably not mediated by the vasoactive intestinal peptide (VIP) receptors since the two hormones had different effects on oocyte maturation and on cAMP production by granulosa cells. In addition the disappearance of the GRF effect observed in the presence of antibodies anti-GH suggested that GRF required the intermediacy of GH to accomplish its effect on oocyte maturation. Finally, GRF did not affect meiotic maturation when dbcAMP was added to the cultures. Our results demonstrate the ability of GRF to accelerate maturation in oocytes from both primed and unprimed rats. Since the presence and the involvement of GRF at the ovarian levels is now well established, the present data strongly suggest an important potential role of GRF in the ovarian physiology.

Animals↗

PubMed1995

Concurrent nitroglycerin administration reduces the efficacy of recombinant tissue-type plasminogen activator in patients with acute anterior wall myocardial infarction.

The aim of this study was to evaluate the impact of concurrent nitroglycerin administration on the thrombolytic efficacy of recombinant tissue-type plasminogen activator (rTPA) in patients with acute anterior myocardial infarction (AMI). Sixty patients (53 men, 7 women; mean age 54 +/- 7 years) with AMI entered the study. Thirty-three patients were randomized to receive rTPA alone (100 mg in 3 hours) (group A) and 27 to receive rTPA plus nitroglycerin (100 micrograms/min) (group B). Time from the onset of chest pain and delivery of rTPA was similar in the two groups of patients. Patients in group A had signs of reperfusion more often than the patients in group B (25 of 33 or 75.7% vs 15 of 27 or 55.5%, p < 0.05). Time to reperfusion was also shorter in group A than in group B (19.6 +/- 9.4 minutes vs 37.8 +/- 5.9 minutes, p < 0.05). Group B had a greater incidence of in-hospital adverse events (9 of 27 vs 5 of 33, p < 0.05) and a higher incidence of coronary artery reocclusion (8 of 15 or 53.3% vs 6 of 25 or 24%, p < 0.05). Peak plasma levels of rTPA antigen were higher in group A compared with group B (1427 +/- 679 vs 512 +/- 312 ng/ml, p < 0.01). In conclusion, concurrent nitroglycerin administration reduces the thrombolytic efficacy of rTPA in patients with AMI probably by lowering the plasma levels of rTPA antigen. The diminished efficacy of rTPA is associated with an adverse outcome.

Antigens↗

PubMed1994

Growth hormone induction of rat granulosa cell tissue-plasminogen activator expression and progesterone synthesis.

The plasminogen activator (PA) system is present in the ovary and appears to be involved both in follicular growth and ovulation. Similarly, the growth hormone (GH) has been demonstrated to positively affect some ovarian activities. Interestingly, GH appears not only as a mediator of gonadotropin effects, but also as having an independent action of its own on the ovary. In the present study we wanted to investigate if GH could affect ovarian plasminogen activator (PA) activity and steroidogenesis. Granulosa cells from immature rats, injected with pregnant mare serum gonadotropin (PMSG) for inducing follicular growth, were cultured for 24 h with increasing concentrations of GH. A significant dose-dependent increase in tPA activity was observed in the GH-treated cells. This effect was exerted at the mRNA level and the use of cycloheximide, a protein synthesis inhibitor, suggested that GH did not require any other intermediary protein for inducing tPA-mRNA. Furthermore, cAMP levels were not affected by GH treatment. Finally, GH was found to increase progesterone (P) synthesis by granulosa cells. The correlation between the PA system and ovulation and the importance of a normal steroidogenesis for the ovarian physiology claim for a key role of GH in the ovarian activities.

Animals↗

PubMed1994

Growth hormone induces in vitro maturation of follicle- and cumulus-enclosed rat oocytes.

The aim of this study was to assess the possible role of growth hormone (GH) on rat oocyte maturation. This effect was analyzed in follicle-enclosed, cumulus-enclosed and denuded oocytes obtained from immature pregnant mare's serum gonadotropin (PMSG)-treated rats. The addition of GH to the cultures significantly accelerated maturation in both follicle- and cumulus-enclosed oocytes while no effect was seen on denuded oocytes maturation. Also, GH accelerated meiotic maturation in follicle-enclosed oocytes from immature untreated rats. The GH action was not mediated by lactogenic receptors since prolactin (Prl) did not affect the maturation process while it was mediated by insulin growth factor-I (IGF-I) as suggested by the block of GH action observed in the presence of antibodies anti-IGF-I. Finally, no GH effect was found when dbcAMP was added to the cultures. Our results demonstrate that GH is capable of inducing maturation in oocytes from both primed and unprimed rats. Since the presence of physiological levels of GH in the ovary is now well established, the present data strongly suggest a potential relevance of GH in the reproductive biology.

Animals↗

PubMed1989

[1.5 T MR in the diagnosis of parotid masses: comparison with ultrasonography].

Twenty-two patients who presented with laterocervical retromandibular enlargement were examined with both US and MR imaging to assess the intrinsic/extrinsic relationship of the mass to the parotid gland, the involvement of the facial nerve and adjacent structures, as well as the nature of the mass. Both US and MR imaging proved to be poorly specific in the characterization of the inflammatory lesions. Within the mass, both methods revealed high sensitivity (100%) in identifying the lesions, even very small ones. MR imaging allowed the lesion to be accurately located, the facial nerve to be identified, and its possible infiltration to be evaluated, with higher reliability than US, thanks to its higher contrast resolution and to its multiplanarity. Neither US nor MR imaging allowed the benign/malignant nature of the lesion to be assessed. On the basis of their experience, the authors suggest the use of T2-weighted MR sequences, with long TR and TE, to differentiate pleomorphic adenomas from other histotypes, after US assessment of the solid nature of parotid masses.

Adenocarcinoma↗