SECRETION OF PROGESTERONE BY HUMAN OVARIES PERFUSED IN VITRO

1975 ◽  
Vol 79 (1) ◽  
pp. 111-121 ◽  
Author(s):  
H. Fukunishi ◽  
H. Mickan ◽  
J. Zander
Keyword(s):  
Ovarian Function ◽  
Sodium Lactate ◽  
Bicarbonate Buffer ◽  
Ldh Activity ◽  
Progesterone Secretion ◽  
Experimental Approaches ◽  
Lactate And Pyruvate ◽  
Human Ovaries

ABSTRACT A system for the perfusion of isolated human ovaries is described. Krebs-Ringer bicarbonate buffer (pH 7.4) containing glucose, sodium lactate and pyruvate was perfused at a flow rate of 5–8 ml/min at 37°C through the ovarian artery. Oxygen uptake, LDH-activity, pH and progesterone secretion were determined as parameters of viability of the perfused organ. Our results demonstrate that a relatively simple system used for perfusion was able to preserve ovarian function for at least two hours. This experimental design should not be regarded as physiological but in addition to other experimental approaches it might provide information on the physiology of the human ovary. Though lower values of progesterone secretion than in vivo were found, a correlation of secretion and functional stage of the ovaries could be demonstrated.

Lactate and pyruvate gradients between red blood cells and plasma during acute asphyxia

1964 ◽  
Vol 19 (6) ◽  
pp. 1100-1104 ◽  
Author(s):  
Salha S. Daniel ◽  
Hisayo O. Morishima ◽  
L. Stanley James ◽  
Karlis Adamsons
Keyword(s):  
Sodium Lactate ◽  
Red Cells ◽  
Red Cell ◽  
Cell Ratio ◽  
Lactate And Pyruvate ◽  
The Mean ◽  
Endogenous Release ◽  
Pyruvate Ratio

The rate of equilibration of lactate and pyruvate between plasma and red cells has been studied during asphyxia and following addition of sodium lactate in vivo and in vitro. In the resting, well-oxygenated guinea pig, the mean plasma/red cell ratio of lactate was 1.55 and that of pyruvate 2.47. During asphyxia, the plasma/red cell ratio of lactate rose and that of pyruvate fell, indicating a delay in equilibration. Incomplete equilibration affected particularly the lactate/pyruvate ratio in the two compartments. Infused neutral sodium lactate penetrated the red cells at a rate comparable to that observed following endogenous release of lactic acid during acute asphyxia. In vitro at pH 6.8@#X2013;7.4 at 38 C, the time to 50% equilibration of lactate between plasma and cells of human blood was less than 2 min. It is concluded that during acute asphyxia and resuscitation whole blood values of lactate and pyruvate do not bear a constant relationship to those of plasma. lactate/pyruvate ratio Submitted on March 16, 1964

THE OVARIAN FOLLICLE OF THE SHEEPINHIBITION OF OESTROGEN SECRETION BY LUTEINIZING HORMONE

1974 ◽  
Vol 61 (3) ◽  
pp. 455-463 ◽  
Author(s):  
R. M. MOOR
Keyword(s):  
Luteinizing Hormone ◽  
Organ Culture ◽  
Culture Medium ◽  
Ovarian Follicle ◽  
Corpora Lutea ◽  
In Vitro Techniques ◽  
Progesterone Secretion ◽  
Experimental Approaches

SUMMARY The object of this study was to test the hypothesis that levels of luteinizing hormone (LH), comparable to those circulating at oestrus, inhibit oestrogen secretion from Graafian follicles of sheep. Three experimental approaches were used. Follicles maintained in organ culture secreted high levels of oestrogen into the medium throughout a 7-day culture period; almost no progesterone was secreted under such conditions. By contrast, oestrogen secretion declined precipitously and progesterone secretion increased rapidly after the addition of LH (0·25 μg–10 μg NIH-LH-S 17/ml) to the culture medium. In experiments combining in-vivo and in-vitro techniques, follicles were obtained from sheep from which the corpora lutea had been removed 24 h previously. The large follicles explanted from these sheep secreted high levels of oestrogen throughout the 7 days in culture. Insignificant amounts of oestrogen were, however, secreted in culture by large follicles that had been explanted from sheep in which 1 mg LH had been infused between 18 and 24 h after removal of the corpus luteum. Experiments carried out entirely in vivo showed that intravenous infusion of 1 mg LH into sheep from which the corpora lutea had been removed 18 h previously prevented the ovaries from secreting, during the ensuing 22 h, the large amounts of oestrogen they would otherwise have produced. The results demonstrate that oestrogen secretion by large Graafian follicles is terminated both in vitro and in vivo by an amount of LH corresponding to that released at oestrus.

scholarly journals Discovery of vanoxerine dihydrochloride as a CDK2/4/6 triple-inhibitor for the treatment of human hepatocellular carcinoma

2021 ◽  
Vol 27 (1) ◽  
Author(s):  
Ying Zhu ◽  
Kun-Bin Ke ◽  
Zhong-Kun Xia ◽  
Hong-Jian Li ◽  
Rong Su ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Cycle Progression ◽  
G1 Arrest ◽  
Huh7 Cells ◽  
Synergistic Cytotoxicity ◽  
Combination Study ◽  
Experimental Approaches ◽  
Induced Apoptosis

Abstract Background Cyclin-dependent kinases 2/4/6 (CDK2/4/6) play critical roles in cell cycle progression, and their deregulations are hallmarks of hepatocellular carcinoma (HCC). Methods We used the combination of computational and experimental approaches to discover a CDK2/4/6 triple-inhibitor from FDA approved small-molecule drugs for the treatment of HCC. Results We identified vanoxerine dihydrochloride as a new CDK2/4/6 inhibitor, and a strong cytotoxicdrugin human HCC QGY7703 and Huh7 cells (IC50: 3.79 μM for QGY7703and 4.04 μM for Huh7 cells). In QGY7703 and Huh7 cells, vanoxerine dihydrochloride treatment caused G1-arrest, induced apoptosis, and reduced the expressions of CDK2/4/6, cyclin D/E, retinoblastoma protein (Rb), as well as the phosphorylation of CDK2/4/6 and Rb. Drug combination study indicated that vanoxerine dihydrochloride and 5-Fu produced synergistic cytotoxicity in vitro in Huh7 cells. Finally, in vivo study in BALB/C nude mice subcutaneously xenografted with Huh7 cells, vanoxerine dihydrochloride (40 mg/kg, i.p.) injection for 21 days produced significant anti-tumor activity (p < 0.05), which was comparable to that achieved by 5-Fu (10 mg/kg, i.p.), with the combination treatment resulted in synergistic effect. Immunohistochemistry staining of the tumor tissues also revealed significantly reduced expressions of Rb and CDK2/4/6in vanoxerinedihydrochloride treatment group. Conclusions The present study isthe first report identifying a new CDK2/4/6 triple inhibitor vanoxerine dihydrochloride, and demonstrated that this drug represents a novel therapeutic strategy for HCC treatment.

In vitro assessment of food-derived-glucose bioaccessibility and bioavailability in bicameral cell culture system

2020 ◽  
Vol 45 (5) ◽  
pp. 631-637
Author(s):  
Cansu Ozel-Tasci ◽  
Gozde Pilatin ◽  
Ozgur Edeer ◽  
Sukru Gulec
Keyword(s):  
Cell Culture ◽  
Culture System ◽  
Metabolic Diseases ◽  
Enzymatic Digestion ◽  
Cell Culture System ◽  
Culture Studies ◽  
Experimental Approaches ◽  
In Vitro Assessment

AbstractBackgroundFunctional foods can help prevent metabolic diseases, and it is essential to evaluate functional characteristics of foods through in vitro and in vivo experimental approaches.ObjectiveWe aimed to use the bicameral cell culture system combined with the in vitro digestion to evaluate glucose bioavailability.Materials and methodsCake, almond paste, and pudding were modified by adding fiber and replacing sugar with sweeteners and polyols. Digestion process was modeled in test tubes. Rat enterocyte cells (IEC-6) were grown in a bicameral cell culture system to mimic the physiological characteristics of the human intestine. The glucose bioaccessibility and cellular glucose efflux were measured by glucose oxidase assay.Results and discussionThe glucose bioaccessibilities of modified foods were significantly lower (cake: 2.6 fold, almond paste: 9.2 fold, pudding 2.8 fold) than the controls. Cellular glucose effluxes also decreased in the modified cake, almond paste, and pudding by 2.2, 4, and 2 fold respectively compared to their controls.ConclusionOur results suggest that combining in vitro enzymatic digestion with cell culture studies can be a practical way to test in vitro glucose bioaccessibility and bioavailability in functional food development.

scholarly journals Antitumor Activity and Mechanism of Action of the Hormonotoxin, an LHRH Analog Conjugated to Dermaseptin-B2, a Multifunctional Antimicrobial Peptide

2021 ◽  
Author(s):  
Mickael COUTY ◽  
Marie DUSAUD ◽  
Mickael MIRO-PADOVANI ◽  
Liuhui ZHANG ◽  
Patricia ZADIGUE ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Antimicrobial Peptide ◽  
Tumor Cell Line ◽  
Experimental Approaches ◽  
Prostate Cancers ◽  
Innovative Drugs ◽  
Therapeutic Alternatives ◽  
Prostate Tumor Cells

Abstract Prostate cancer represents the most common cancer in men. For patients with advanced or metastatic form, treatments will be able to slow down the progression but cannot cure it even with the used of new targeted therapies. In this context, the development of innovative drugs resulting from the exploration of biodiversity could open new therapeutic alternatives. Dermaseptin-B2 (DRS-B2), a natural multifunctional antimicrobial peptide isolated from the Amazonian frog skin, has been reported to possess antitumor and antiangiogenic activities. To improve DRS-B2 pharmacological properties and target prostate tumor cells more specifically, we have developed a chimeric molecule, called Hormonotoxin (H-B2) which is composed of a DRS-B2 combined with a hormonal analog, d-Lys6-LHRH, to target LHRH-Receptor which is overexpressed in more than 85% of prostate cancers. In vitro H-B2 has a significant antiproliferative effect on the PC3 tumor cell line, with an IC50 value close to that of DRS-B2. The antitumor activity of H-B2 was confirmed in vivo in mouse model xenografted with PC3 tumors and appears to be better tolerated than DRS-B2. Biophysical experiments showed that the addition of the hormonal analog to DRS-B2 did not alter either its secondary structure or its biological activity. Combination of different experimental approaches indicated that H-B2 induces cell death by an apoptotic mechanism whereas DRS-B2 was shown to induce it by necrosis. These results could explain the H-B2 less toxicity compared to DRS-B2. H-B2 represents a promising targeting approach for cancer therapy.

Glucagon increases urinary oxalate excretion in the guinea pig

1995 ◽  
Vol 269 (3) ◽  
pp. E568-E574 ◽  
Author(s):  
R. P. Holmes ◽  
C. H. Hurst ◽  
D. G. Assimos ◽  
H. O. Goodman
Keyword(s):  
Hepatic Metabolism ◽  
Enzymatic Conversion ◽  
Urinary Oxalate ◽  
Oxalate Excretion ◽  
Lactate And Pyruvate ◽  
Urinary Oxalate Excretion ◽  
Glyoxylate Aminotransferase ◽  
Oxalate Synthesis

Factors that influence hepatic oxalate synthesis are poorly defined. Hormones are important regulators of hepatic metabolism and could potentially be involved. The effects of hyperglucagonemia were examined in guinea pigs injected with either saline or pharmacological doses of glucagon for 4 days. Glucagon treatment increased mean urinary oxalate excretion by 77% in male and 34% in female animals. The levels of hepatic peroxisomal enzymes involved in oxalate synthesis declined with glucagon treatment, but experiments with isolated peroxisomes indicated that oxalate synthesis in vitro was unaffected. Glucagon decreased hepatic alanine levels by 66%, lactate by 69%, and pyruvate by 73%, but glycolate and glyoxylate levels were unaffected. This decrease in alanine would substantially lower the activity of alanine-to-glyoxylate aminotransferase activity in vivo and make more glyoxylate available for oxalate synthesis. The decrease in lactate and pyruvate concentrations would stimulate the enzymatic conversion of glyoxylate to oxalate and may account for the increase in oxalate synthesis without an increase in glyoxylate concentration. These results demonstrate that hepatic oxalate synthesis is influenced by metabolic changes and that alterations in hepatic alanine, lactate, and pyruvate concentrations may be important elements.

scholarly journals Estrogen modulates the recruitment of myelopoietic cell progenitors in rat through a stromal cell-independent mechanism involving apoptosis

Blood ◽  
1996 ◽  
Vol 87 (7) ◽  
pp. 2683-2692 ◽  
Author(s):  
NK Shevde ◽  
JW Pike
Keyword(s):  
Estrogen Receptor ◽  
Ovarian Function ◽  
Morphological Changes ◽  
Estrogen Treatment ◽  
Ovariectomized Rats ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Protective Effects ◽  
Hematopoietic Stem

Loss of ovarian function leads to a significant increase in the number of bone-resorbing osteoclasts. Estrogen replacement is known to manifest bone protective effects in the treatment of postmenopausal osteoporosis. In the present study, we used ovariectomized rats to examine the effects of estrogen loss at the osteoclast progenitor colony forming unit-granulocyte macrophage (CFU-GM) level. A significant increase in CFU-GM number was observed as early as 7 days following ovariectomy, and correlated directly with an increase in the number of osteoclast-like cells generated in marrow cultures. The increase in CFU-GM following ovariectomy was abrogated in animals that received estrogen treatment in vivo. A similar suppressive effect was observed on CFU-GM number when ovariectomized rat marrow was treated with estrogen in vitro. This effect was blocked in the presence of the estrogen antihormone ICI 164,384. Thus, the data suggest the possibility that estrogen exerts a direct effect on osteoclast progenitors, and does so through the estrogen receptor-mediated mechanism. Ovariectomy also led to an increase in the early hematopoietic stem/progenitor cell population (Thy 1.1+ cells) as determined by FLOW cytometry methods. Morphological changes as well as terminal deoxynucleotidyl transferase assays revealed that estrogen treatment negated growth factor-induced proliferation of these early progenitors by promoting apoptosis. The cellular effects of estrogen in vitro together with the immunocytochemical detection of the estrogen receptor in these cells, strongly support the contention that in addition to osteoclast progenitors such as CFU-GM, earlier hematopoietic progenitors are also unique cellular targets for estrogen action.

Inhibition of LH-stimulated cyclic AMP formation in pre-ovulatory rat granulosa cells by follicular fluid

1980 ◽  
Vol 95 (1) ◽  
pp. 84-89 ◽  
Author(s):  
Knut Nordenström ◽  
Anita Sjögren ◽  
Lars Hamberger
Keyword(s):  
Granulosa Cells ◽  
Follicular Fluid ◽  
Phosphodiesterase Inhibitor ◽  
Inhibitory Effect ◽  
Female Rats ◽  
Bicarbonate Buffer ◽  
Ovulatory Follicles

Abstract. Immature female rats were injected sc with a single dose of PMSG to induce growth and maturation of ovarian follicles. In the morning of prooestrus the rats were given a single ip injection of LH (10 μg/rat) or 0.154 m NaCl, 2 h prior to sacrifice. Granulosa cells were isolated from the pre-ovulatory follicles and incubated in Krebs bicarbonate buffer, for 1 h with or without in vitro addition of various test substances. Following incubation the amounts of cAMP in tissue plus medium were determined. It was found that the isolated granulosa cells exposed to LH in vivo responded to the addition of LH in vitro with a production of high amounts of cAMP, i.e. these cells were not refractory to LH stimulation and in fact responded better than granulosa cells isolated from ovaries not exposed to LH in vivo. The addition to the incubation medium of follicular fluid (FFl) obtained from pre-ovulatory follicles decreased the effect of LH in vitro when added at a final concentration of 1% and completely abolished it at a concentration of 3%. Removal of steroids from the FFl did not influence the inhibitory effect and the addition of a phosphodiesterase inhibitor (IBMX) in vitro did not alter the results in principle. These results point to the existence of a factor in the FF1 which interacts with the sensitivity of the isolated preovulatory granulosa cells to repeated exposures to LH. Characterization of this factor is subject to further investigations.

Post-ovulation nutritional status in ewes does not influence early conceptus development in vivo or luteotrophic protein secretion in vitro.

1993 ◽  
Vol 1993 ◽  
pp. 58-58
Author(s):  
J.M. Wallace ◽  
R.P. Aitken ◽  
M.A. Cheyne
Keyword(s):  
Pregnancy Rate ◽  
Immunosuppressive Agents ◽  
Maternal Environment ◽  
Embryo Survival ◽  
Domestic Species ◽  
Progesterone Secretion ◽  
Conceptus Development ◽  
In Pregnancy

Overfeeding during early pregnancy compromises pregnancy establishment and /or embryo survival in a variety of domestic species including sheep, cattle and pigs (reviewed by Robinson, 1990). Embryo survival was reduced in recipient ewes receiving a high as opposed to a low plane of nutrition from embryo transfer on day 5 post-ovulation to day 60 of gestation (McKelvey & Robinson, 1988).Similarly high plane feeding for only 12 days starting on day 2 after mating significantly reduced pregnancy rates at day 60 ( Parr et al .,1987). Although not extensively monitored in either study, peripheral progesterone concentrations were inversely correlated with feed intake. Indeed, the reduction in pregnancy rate in high plane ewes in Parr's study was reversed by progesterone supplementation on days 8-14 after mating.The inhibition of luteolysis and maintenance of adequate progesterone secretion by the corpus luteum is central to the maternal recognition of pregnancy in sheep ( Bazer et al .,1991 ). Progesterone plays a major role in controlling maternal secretion of nutrients, growth factors , immunosuppressive agents .enzymes and steroids required for successful embryo development. It seems likely therefor that the mechanisms underlying nutritionally induced differences in pregnancy rate and embryo survival may operate via changes in progesterone levels which in turn alter the secretory dialogue between the conceptus and its maternal environment.

scholarly journals Implications and Current Limitations of Oogenesis from Female Germline or Oogonial Stem Cells in Adult Mammalian Ovaries

Cells ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 93 ◽  
Author(s):  
Jessica Martin ◽  
Dori Woods ◽  
Jonathan Tilly
Keyword(s):  
Stem Cells ◽  
Adult Stem Cells ◽  
Ovarian Function ◽  
Mammalian Species ◽  
Large Body ◽  
The Body ◽  
Human Female ◽  
Female Germline

A now large body of evidence supports the existence of mitotically active germ cells in postnatal ovaries of diverse mammalian species, including humans. This opens the possibility that adult stem cells naturally committed to a germline fate could be leveraged for the production of female gametes outside of the body. The functional properties of these cells, referred to as female germline or oogonial stem cells (OSCs), in ovaries of women have recently been tested in various ways, including a very recent investigation of the differentiation capacity of human OSCs at a single cell level. The exciting insights gained from these experiments, coupled with other data derived from intraovarian transplantation and genetic tracing analyses in animal models that have established the capacity of OSCs to generate healthy eggs, embryos and offspring, should drive constructive discussions in this relatively new field to further exploring the value of these cells to the study, and potential management, of human female fertility. Here, we provide a brief history of the discovery and characterization of OSCs in mammals, as well as of the in-vivo significance of postnatal oogenesis to adult ovarian function. We then highlight several key observations made recently on the biology of OSCs, and integrate this information into a broader discussion of the potential value and limitations of these adult stem cells to achieving a greater understanding of human female gametogenesis in vivo and in vitro.

Sign in / Sign up

Export Citation Format

Share Document