The effect of PCB126, 77, and 153 on the intracellular mobilization of Ca+2 in bovine granulosa and luteal cells after FSH and LH surge in vitro

2013 ◽  
Vol 16 (3) ◽  
pp. 417-424 ◽  
Author(s):  
J. Mlynarczuk ◽  
M. Kowalik
Keyword(s):  
Uv Light ◽  
Environmental Pollutants ◽  
Ccd Camera ◽  
Cell Types ◽  
Functional Differentiation ◽  
Negative Influence ◽  
Luteal Cells ◽  
Aroclor 1248 ◽  
Intracellular Ca

Abstract Polychlorinated biphenyls (PCBs) are a group of persistent environmental pollutants that impair cattle reproduction. Among other effects, PCBs can disturb the intracellular mobilization of Ca+2 in several cell types. Hence, it is possible that they disrupt the transduction of intracellular signals generated from gonadotropin (FSH/LH) receptors. In steroidogenic ovarian cells, a defect in Ca+2 mobilization may have a detrimental influence on two important processes: the secretion of steroids (E2 or/and P4) and their morphological and functional differentiation. The aim of this study was to determine the influence of PCBs: 126 (dioxin-like) 77 (ambivalent) and 153 (estrogen-like) and a mixture of PCBs (Aroclor 1248) on these processes. Bovine granulosa and luteal cells were incubated for 72 hrs with PCBs (100 ng/ml), followed by Fura 2AM dye, and the fluctuations in intracellular Ca+2 mobilization after FSH/LH treatment were determined using an inverted microscope coupled with a CCD camera. The intensity and area of fluorescence excited by UV light were detected in the green spectrum of visible light. Aroclor 1248 and PCBs 153 and 77 significantly decreased (P < 0.01-0.001) the effect of FSH on intracellular Ca+2 mobilization in granulosa cells. In luteal cells, the most effective PCB on this process was PCB 77. The results revealed adverse effects of PCBs on the mobilization of intracellular Ca+2. Moreover, the estrogen- like congeners were found to more effectively disturb this process than the dioxin-like PCB 126. Hence, it is possible for PCBs to have a negative influence on reproductive processes by affecting calcium mobilization.

Human growth hormone enhances progesterone production by human luteal cells in vitro. II. Evidence of a distinct effect on two luteal cell types

1993 ◽  
Vol 60 (1) ◽  
pp. 47-52 ◽  
Author(s):  
Nicoletta Di Simone ◽  
Roberta Castellani ◽  
Antonio Lanzone ◽  
Alessandro Caruso ◽  
Salvatore Mancuso
Keyword(s):  
Growth Hormone ◽  
Human Growth Hormone ◽  
Human Growth ◽  
Cell Types ◽  
Luteal Cell ◽  
Luteal Cells ◽  
Distinct Effect ◽  
Progesterone Production

scholarly journals Protein kinase C phosphorylates the inositol 1,4,5-trisphosphate receptor type 2 and decreases the mobilization of Ca2+in pancreatoma AR4-2J cells

2007 ◽  
Vol 192 (3) ◽  
pp. 659-668 ◽  
Author(s):  
Guillaume Arguin ◽  
Yannik Regimbald-Dumas ◽  
Marc-Olivier Fregeau ◽  
Annabelle Z Caron ◽  
Gaetan Guillemette
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Cell Types ◽  
Excitable Cells ◽  
Kinase C ◽  
Inositol 1,4,5 Trisphosphate ◽  
Intracellular Ca ◽  
Pre Treatment ◽  
Trisphosphate Receptor

In non-excitable cells, the inositol 1,4,5-trisphosphate receptor channel, which plays a major (IP3R) is an intracellular Ca2+ role in Ca2+ signalling. Three isoforms of IP3R have been identified (IP3R-1, IP3R-2 and IP3R-3) and most cell types express different proportions of each isoform. The differences between the pharmacological and functional properties of the various isoforms of IP3R are poorly understood. AR4-2J cells, which express almost exclusively (~86%) the IP3R-2, represent an interesting model to study this particular isoform. Here, we investigated a regulatory mechanism by which protein kinase C (PKC) influences IP3R-2-mediated Ca2+ release. Using an immunoprecipitation approach, we confirmed that AR4-2J cells express almost exclusively the IP3R-2 isoform. Using an in vitro phosphorylation assay, we showed that the immunopurified IP3R-2 was efficiently phosphorylated by exogenous PKC. In intact AR4-2J cells metabolically labelled with 32Pi, we showed that phorbol-12-myristate-13-acetate (PMA) and Ca2+ mobilizing agonists cause the phosphorylation of IP3R-2. In saponin-permeabilized AR4-2J cells, IP3-induced Ca2+ release was reduced after a pre-treatment with PMA or with exogenous PKC. PMA also reduced the Ca2+ response of intact AR4-2J cells stimulated with carbachol and epidermal growth factor, two agonists that use different receptor types to activate phospholipase C. These results demonstrate that PKC decreases the Ca2+mobilizing activity of IP3R-2 and thus exerts a negative feedback on the agonists-induced Ca2+ response of AR4-2J cells.

Conversion of 5(10)-oestrene-3β,17β-diol to 19-nor-4-ene-3-ketosteroids by luteal cells in vitro: possible involvement of the 3β-hydroxysteroid dehydrogenase/isomerase

1991 ◽  
Vol 129 (2) ◽  
pp. 233-243 ◽  
Author(s):  
C. M. H. Lee ◽  
F. R. Tekpetey ◽  
D. T. Armstrong ◽  
M. W. Khalil
Keyword(s):  
Granulosa Cells ◽  
Ovarian Follicle ◽  
Cell Types ◽  
Hydroxysteroid Dehydrogenase ◽  
Corpora Lutea ◽  
Dependent Manner ◽  
Luteal Cells ◽  
Porcine Granulosa Cells ◽  
Porcine Luteal Cells

ABSTRACT We have previously suggested that in porcine granulosa cells, a putative intermediate, 5(10)-oestrene-3,17-dione is involved in 4-oestrene-3,17-dione (19-norandrostenedione; 19-norA) and 4-oestren-17β-ol-3-one (19-nortestosterone: 19-norT) formation from C19 aromatizable androgens. In this study, luteal cells prepared from porcine, bovine and rat corpora lutea by centrifugal elutriation were used as a source of 3β-hydroxysteroid dehydrogenase/isomerase in order to investigate the role of this enzyme in the biosynthesis of 19-norsteroids. Small porcine luteal cells made mainly 19-norT and large porcine luteal cells 19-norA from 5(10)-oestrene-3β,17β-diol, the reduced product of the putative intermediate 5(10)-oestrene-3,17-dione. However, neither small nor large cells metabolized androstenedione to 19-norsteroids. Serum and serum plus LH significantly stimulated formation of both 19-norA and 19-norT from 5(10)-oestrene-3β,17β-diol, compared with controls. Inhibitors of the 3β-hydroxysteroid dehydrogenase/isomerase (trilostane and cyanoketone) significantly reduced formation of 19-norT in small porcine luteal cells and 19-norA in large porcine luteal cells, although they were effective at different concentrations in each cell type. In parallel incubations, formation of [4-14C]androstenedione from added [4-14C]dehydroepiandrosterone was also inhibited by cyanoketone in both small and large porcine luteal cells in a dose-dependent manner; however, trilostane (up to 100 μmol/l) did not inhibit androstenedione formation in large porcine luteal cells. In addition, the decrease in progesterone synthesis induced by trilostane and cyanoketone (100 μmol/l each) was accompanied by a parallel accumulation of pregnenolone in both cell types. These results suggest that 3β-hydroxysteroid dehydrogenase/isomerase, or a closely related enzyme, present in small and large porcine luteal cells can convert added 5(10)-3β-hydroxysteroids into 19-nor-4(5)-3-kestosteroids in vitro. In the porcine ovarian follicle, therefore, formation of 19-norA from androstenedione can be envisaged as a two-step enzymatic process: 19-demethylation of androstenedione to produce the putative intermediate 5(10)-oestrene-3,17-dione, and subsequent isomerization to 19-norA. In contrast to granulosa cells, porcine luteal cells synthesized 19-norA or 19-norT only when provided with the appropriate substrate. Unfractionated rat luteal cells also metabolized 5(10)-oestrene-3β,17β-diol to a mixture of 19-norA and 19-norT; conversion was inhibited by trilostane. In addition, small bovine luteal cells synthesized mainly 19-norT and formation was also inhibited by trilostane and cyanoketone. In addition to 19-norA, an unknown metabolite, formed in low amounts by large porcine luteal cells, appears to be related to another steroid which accumulated at high inhibitor concentrations; it may represent 5(10)-oestrene-3,17-dione postulated as a putative intermediate formed during 19-norsteroid biosynthesis. Journal of Endocrinology (1991) 129, 233–243

scholarly journals ATP increases within the lumen of the endoplasmic reticulum upon intracellular Ca2+release

2014 ◽  
Vol 25 (3) ◽  
pp. 368-379 ◽  
Author(s):  
Neelanjan Vishnu ◽  
Muhammad Jadoon Khan ◽  
Felix Karsten ◽  
Lukas N. Groschner ◽  
Markus Waldeck-Weiermair ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Single Cells ◽  
Cell Types ◽  
Additional Energy ◽  
Intracellular Ca ◽  
A Cell ◽  
Specific Regulation ◽  
Amp Activated Protein Kinase ◽  
Different Cell Types

Multiple functions of the endoplasmic reticulum (ER) essentially depend on ATP within this organelle. However, little is known about ER ATP dynamics and the regulation of ER ATP import. Here we describe real-time recordings of ER ATP fluxes in single cells using an ER-targeted, genetically encoded ATP sensor. In vitro experiments prove that the ATP sensor is both Ca2+and redox insensitive, which makes it possible to monitor Ca2+-coupled ER ATP dynamics specifically. The approach uncovers a cell type–specific regulation of ER ATP homeostasis in different cell types. Moreover, we show that intracellular Ca2+release is coupled to an increase of ATP within the ER. The Ca2+-coupled ER ATP increase is independent of the mode of Ca2+mobilization and controlled by the rate of ATP biosynthesis. Furthermore, the energy stress sensor, AMP-activated protein kinase, is essential for the ATP increase that occurs in response to Ca2+depletion of the organelle. Our data highlight a novel Ca2+-controlled process that supplies the ER with additional energy upon cell stimulation.

ERK1/2 mediates sperm acrosome reaction through elevation of intracellular calcium concentration

Zygote ◽  
2014 ◽  
Vol 23 (5) ◽  
pp. 652-661 ◽  
Author(s):  
Yael Jaldety ◽  
Haim Breitbart
Keyword(s):  
Acrosome Reaction ◽  
Reproductive Tract ◽  
Egf Receptor ◽  
Direct Determination ◽  
Cell Types ◽  
Mek Inhibitor ◽  
Female Reproductive Tract ◽  
Ionophore A23187 ◽  
Intracellular Ca

SummaryMammalian sperm acquire fertilization capacity after residing in the female reproductive tract for a few hours in a process called capacitation. Only capacitated sperm can bind the zona pellucida (ZP) of the egg and undergo the acrosome reaction, a process that allows penetration and fertilization. Extracellular signal regulated kinase (ERK1/2) mediates signalling in many cell types, however its role in sperm function is largely unknown. Here we show that ERK1/2 is highly phosphorylated/activated after a short incubation of mouse sperm under capacitation conditions and that this phosphorylation is reduced after longer incubation. Further phosphorylation was observed upon addition of crude extract of egg ZP or epidermal growth factor (EGF). The mitogen-activated ERK-kinase (MEK) inhibitor U0126 abolished ERK1/2 phosphorylation, in vitro fertilization rate and the acrosome reaction induced by ZP or EGF but not by the Ca2+-ionophore A23187. Moreover, inhibition of ERK1/2 along the capacitation process diminished almost completely the sperm's ability to go through the acrosome reaction, while inhibition at the end of capacitation attenuated the acrosome reaction rate by only 45%. The fact that the acrosome reaction, induced by the Ca2+ -ionophore A23187, was not inhibited by U0126 suggests that ERK1/2 mediates the acrosome reaction by activating Ca2+ transport into the cell. Direct determination of intracellular [Ca2+] revealed that Ca2+ influx induced by EGF or ZP was completely blocked by U0126. Thus, it has been established that the increase in ERK1/2 phosphorylation/activation in response to ZP or by activation of the EGF receptor (EGFR) by EGF, is a key event for intracellular Ca2+ elevation and the subsequent occurrence of the acrosome reaction.

scholarly journals “Ryanopathies” and RyR2 dysfunctions: can we further decipher them using in vitro human disease models?

2021 ◽  
Vol 12 (11) ◽  
Author(s):  
Yvonne Sleiman ◽  
Alain Lacampagne ◽  
Albano C. Meli
Keyword(s):  
Intracellular Calcium ◽  
Ryanodine Receptor ◽  
Calcium Release ◽  
Current Knowledge ◽  
Cell Types ◽  
Calcium Release Channel ◽  
Release Channel ◽  
Cellular Environment ◽  
Intracellular Ca

AbstractThe regulation of intracellular calcium (Ca2+) homeostasis is fundamental to maintain normal functions in many cell types. The ryanodine receptor (RyR), the largest intracellular calcium release channel located on the sarco/endoplasmic reticulum (SR/ER), plays a key role in the intracellular Ca2+ handling. Abnormal type 2 ryanodine receptor (RyR2) function, associated to mutations (ryanopathies) or pathological remodeling, has been reported, not only in cardiac diseases, but also in neuronal and pancreatic disorders. While animal models and in vitro studies provided valuable contributions to our knowledge on RyR2 dysfunctions, the human cell models derived from patients’ cells offer new hope for improving our understanding of human clinical diseases and enrich the development of great medical advances. We here discuss the current knowledge on RyR2 dysfunctions associated with mutations and post-translational remodeling. We then reviewed the novel human cellular technologies allowing the correlation of patient’s genome with their cellular environment and providing approaches for personalized RyR-targeted therapeutics.

Ultrastructural Changes in Three Different Mammalian Cells Following Ultraviolet Laser Irradiation

1972 ◽  
Vol 30 ◽  
pp. 350-351
Author(s):  
K. Shankar Narayan ◽  
Kailash C. Gupta ◽  
Tohru Okigaki
Keyword(s):  
Ultraviolet Light ◽  
Mammalian Cells ◽  
Biological Effects ◽  
Survival Rates ◽  
Chinese Hamster ◽  
Cell Types ◽  
Differential Sensitivity ◽  
Ultrastructural Changes ◽  
Ultraviolet Laser

The biological effects of short-wave ultraviolet light has generally been described in terms of changes in cell growth or survival rates and production of chromosomal aberrations. Ultrastructural changes following exposure of cells to ultraviolet light, particularly at 265 nm, have not been reported.We have developed a means of irradiating populations of cells grown in vitro to a monochromatic ultraviolet laser beam at a wavelength of 265 nm based on the method of Johnson. The cell types studies were: i) WI-38, a human diploid fibroblast; ii) CMP, a human adenocarcinoma cell line; and iii) Don C-II, a Chinese hamster fibroblast cell strain. The cells were exposed either in situ or in suspension to the ultraviolet laser (UVL) beam. Irradiated cell populations were studied either "immediately" or following growth for 1-8 days after irradiation.Differential sensitivity, as measured by survival rates were observed in the three cell types studied. Pattern of ultrastructural changes were also different in the three cell types.

Ultrastructural observations on the in vitro cytoadherence of Plasmodium falciparum infected red blood cells

1990 ◽  
Vol 48 (3) ◽  
pp. 914-915
Author(s):  
D.J.P. Ferguson ◽  
A.R. Berendt ◽  
J. Tansey ◽  
K. Marsh ◽  
C.I. Newbold
Keyword(s):  
Plasmodium Falciparum ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Umbilical Vein ◽  
Cell Types ◽  
Amelanotic Melanoma ◽  
Cytoplasmic Process ◽  
Umbilical Vein Endothelial Cells

In human malaria, the most serious clinical manifestation is cerebral malaria (CM) due to infection with Plasmodium falciparum. The pathology of CM is thought to relate to the fact that red blood cells containing mature forms of the parasite (PRBC) cytoadhere or sequester to post capillary venules of various tissues including the brain. This in vivo phenomenon has been studied in vitro by examining the cytoadherence of PRBCs to various cell types and purified proteins. To date, three Ijiost receptor molecules have been identified; CD36, ICAM-1 and thrombospondin. The specific changes in the PRBC membrane which mediate cytoadherence are less well understood, but they include the sub-membranous deposition of electron-dense material resulting in surface deformations called knobs. Knobs were thought to be essential for cytoadherence, lput recent work has shown that certain knob-negative (K-) lines can cytoadhere. In the present study, we have used electron microscopy to re-examine the interactions between K+ PRBCs and both C32 amelanotic melanoma cells and human umbilical vein endothelial cells (HUVEC).We confirm previous data demonstrating that C32 cells possess numerous microvilli which adhere to the PRBC, mainly via the knobs (Fig. 1). In contrast, the HUVEC were relatively smooth and the PRBCs appeared partially flattened onto the cell surface (Fig. 2). Furthermore, many of the PRBCs exhibited an invagination of the limiting membrane in the attachment zone, often containing a cytoplasmic process from the endothelial cell (Fig. 2).

Multi-mode light microscopy of microtubule assembly dynamics and chromosome movement in vivo and In vitro

1996 ◽  
Vol 54 ◽  
pp. 730-731
Author(s):  
E. D. Salmon ◽  
J. C. Waters ◽  
C. Waterman-Storer
Keyword(s):  
Imaging System ◽  
Ccd Camera ◽  
Transmitted Light ◽  
Microtubule Assembly ◽  
Live Cells ◽  
Optical Efficiency ◽  
Multiple Band ◽  
Multi Mode

We have developed a multi-mode digital imaging system which acquires images with a cooled CCD camera (Figure 1). A multiple band pass dichromatic mirror and robotically controlled filter wheels provide wavelength selection for epi-fluorescence. Shutters select illumination either by epi-fluorescence or by transmitted light for phase contrast or DIC. Many of our experiments involve investigations of spindle assembly dynamics and chromosome movements in live cells or unfixed reconstituted preparations in vitro in which photodamage and phototoxicity are major concerns. As a consequence, a major factor in the design was optical efficiency: achieving the highest image quality with the least number of illumination photons. This principle applies to both epi-fluorescence and transmitted light imaging modes. In living cells and extracts, microtubules are visualized using X-rhodamine labeled tubulin. Photoactivation of C2CF-fluorescein labeled tubulin is used to locally mark microtubules in studies of microtubule dynamics and translocation. Chromosomes are labeled with DAPI or Hoechst DNA intercalating dyes.

Role of the 807 C/T Polymorphism of the α2 Gene in Platelet GP Ia Collagen Receptor Expression and Function

1999 ◽  
Vol 81 (06) ◽  
pp. 951-956 ◽  
Author(s):  
J. Corral ◽  
R. González-Conejero ◽  
J. Rivera ◽  
F. Ortuño ◽  
P. Aparicio ◽  
...  
Keyword(s):  
Venous Thrombosis ◽  
Cell Types ◽  
Receptor Expression ◽  
Case Control Studies ◽  
Platelet Surface ◽  
Vitro Analysis ◽  
And Function ◽  
In Vitro Analysis

SummaryThe variability of the platelet GP Ia/IIa density has been associated with the 807 C/T polymorphism (Phe 224) of the GP Ia gene in American Caucasian population. We have investigated the genotype and allelic frequencies of this polymorphism in Spanish Caucasians. The T allele was found in 35% of the 284 blood donors analyzed. We confirmed in 159 healthy subjects a significant association between the 807 C/T polymorphism and the platelet GP Ia density. The T allele correlated with high number of GP Ia molecules on platelet surface. In addition, we observed a similar association of this polymorphism with the expression of this protein in other blood cell types. The platelet responsiveness to collagen was determined by “in vitro” analysis of the platelet activation and aggregation response. We found no significant differences in these functional platelet parameters according to the 807 C/T genotype. Finally, results from 3 case/control studies involving 302 consecutive patients (101 with coronary heart disease, 104 with cerebrovascular disease and 97 with deep venous thrombosis) determined that the 807 C/T polymorphism of the GP Ia gene does not represent a risk factor for arterial or venous thrombosis.

Sign in / Sign up

Export Citation Format

Share Document