THE CONVERSION OF PROGESTERONE TO 16α-HYDROXY-PREGN-4-ENE-3,20-DIONE AND ANDROST-4-ENE-3,17-DIONE BY HUMAN PLACENTA IN VITRO

1963 ◽  
Vol 43 (4) ◽  
pp. 510-520 ◽  
Author(s):  
Brian Little ◽  
Ann Shaw ◽  
Robert Purdy
Keyword(s):  
Human Placenta ◽  
Radiochemical Purity ◽  
Supernatant Fraction ◽  
Normal Human ◽  
Soluble Supernatant ◽  
In Pregnancy

ABSTRACT Using the soluble supernatant fraction of a homogenate of normal human placenta and employing reduced triphosphopyridine as cofactor, the conversion of progesterone to 16α-hydroxyprogesterone and androstenedione was demonstrated. Tests were made of the radiochemical purity of the products. The possible role of 16α-hydroxylated steroids for the biosynthesis of oestriol in pregnancy is discussed.

THE CONVERSION OF PROGESTERONE TO 17α-HYDROXYPROGESTERONE BY HUMAN PLACENTA IN VITRO

1961 ◽  
Vol 36 (3) ◽  
pp. 455-461 ◽  
Author(s):  
Brian Little ◽  
Ann Shaw
Keyword(s):  
Human Placenta ◽  
Radiochemical Purity ◽  
Specific Activity ◽  
Fluid Fraction ◽  
Counter Current ◽  
Soluble Supernatant ◽  
Counter Current Distribution ◽  
Generating System ◽  
Constant Specific Activity

ABSTRACT The conversion of progesterone to 17α-hydroxyprogesterone by the soluble fraction of human placenta has been demonstrated in vitro. The incubation system contained the soluble supernatant fluid fraction of placental homogenate (105 000 × g), progesterone 4-14C as substrate, authentic 17α-hydroxyprogesterone as trap and a reduced triphosphopyridine nucleotide generating system as cofactor. The 17α-hydroxyprogesterone formed was isolated chromatographically and radiochemical purity was demonstrated by constant specific activity in a counter current distribution. Constant specific activity and radiochemical purity of the oxidation product and the acetylated derivative was also shown.

scholarly journals Bisphenol A Altersβ-hCG and MIF Release by Human Placenta: AnIn VitroStudy to Understand the Role of Endometrial Cells

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
C. Mannelli ◽  
F. Ietta ◽  
C. Carotenuto ◽  
R. Romagnoli ◽  
A. Z. Szostek ◽  
...  
Keyword(s):  
Bisphenol A ◽  
Conditioned Medium ◽  
Human Placenta ◽  
Environmental Chemicals ◽  
Endometrial Cells ◽  
Direct Exposure ◽  
And Control ◽  
Cell Conditioned Medium

A proper fetomaternal immune-endocrine cross-talk in pregnancy is fundamental for reproductive success. This might be unbalanced by exposure to environmental chemicals, such as bisphenol A (BPA). As fetoplacental contamination with BPA originates from the maternal compartment, this study investigated the role of the endometrium in BPA effects on the placenta. To this end,in vitrodecidualized stromal cells were exposed to BPA 1 nM, and their conditioned medium (diluted 1 : 2) was used on chorionic villous explants from human placenta. Parallel cultures of placental explants were directly exposed to 0.5 nM BPA while, control cultures were exposed to the vehicle (EtOH 0.1%). After 24–48 h, culture medium from BPA-treated and control cultures was assayed for concentration of hormone human Chorionic Gonadotropin (β-hCG) and cytokine Macrophage Migration Inhibitory Factor (MIF). The results showed that direct exposure to BPA stimulated the release of both MIF andβ-hCG. These effects were abolished/diminished in placental cultures exposed to endometrial cell-conditioned medium. GM-MS analysis revealed that endometrial cells retain BPA, thus reducing the availability of this chemical for the placenta. The data obtained highlight the importance ofin vitromodels including the maternal component in reproducing the effects of environmental chemicals on human fetus/placenta.

Human placental vitamin B6 (pyridoxal) transport: normal characteristics and effects of ethanol

1992 ◽  
Vol 262 (6) ◽  
pp. R966-R974 ◽  
Author(s):  
S. Schenker ◽  
R. F. Johnson ◽  
J. D. Mahuren ◽  
G. I. Henderson ◽  
S. P. Coburn
Keyword(s):  
Human Placenta ◽  
Binding Sites ◽  
Vitamin B6 ◽  
Passive Transport ◽  
Short Term ◽  
Placental Transport ◽  
Normal Human ◽  
Important Form ◽  
Composite Data ◽  
In Pregnancy

The aims of this study were to define normal human placental transport of pyridoxal, an important form of vitamin B6 in pregnancy, and to determine the effect of short-term alcohol on this process. Our studies used the isolated single cotyledon from the term placenta. Pyridoxal crossed the human placenta readily in both directions, but the transfer was a little less than half that of antipyrine and was significantly greater in the direction of the fetus. Pyridoxine appeared to have a similar clearance from the maternal compartment as pyridoxal, but transport of intact pyridoxal 5'-phosphate was much smaller. There was no saturable transfer of pyridoxal, and it was not transferred from the maternal to fetal compartments against a concentration gradient. Placental concentration of pyridoxal exceeded both maternal and fetal perfusate pyridoxal concentrations, but this concentration was equal for both perfusion directions. These composite data are most suggestive of passive transport of pyridoxal across the placenta, binding of the vitamin in the placenta as an explanation for its concentration there, and greater phosphorylation of pyridoxal in the placenta when the compound is transferred in the fetal direction, possibly displacing pyridoxal from its binding sites and permitting its greater release into the fetal compartment. Alcohol, 400-250 mg/dl over 2.5 h, inhibited the transport of pyridoxal from the maternal to fetal compartments by approximately 42% (P = 0.03) and resulted in a lower transfer of pyridoxal 5'-phosphate into the fetal perfusate (P = 0.02).

scholarly journals The Role of Megalin in the Transport of Gentamicin Across BeWo Cells, an In Vitro Model of the Human Placenta

2015 ◽  
Vol 17 (5) ◽  
pp. 1193-1199 ◽  
Author(s):  
Amal A. Akour ◽  
Mary Jayne Kennedy ◽  
Phillip M. Gerk
Keyword(s):  
Human Placenta ◽  
In Vitro Model ◽  
Bewo Cells ◽  
Vitro Model

Neuronal plasticity in chronic pancreatitis is mediated via the neurturin/GFRα2 axis

2012 ◽  
Vol 303 (9) ◽  
pp. G1017-G1028 ◽  
Author(s):  
Ihsan Ekin Demir ◽  
Kun Wang ◽  
Elke Tieftrunk ◽  
Nathalia A. Giese ◽  
Baocai Xing ◽  
...  
Keyword(s):  
Chronic Pancreatitis ◽  
Glial Cell ◽  
Neurotrophic Factor ◽  
Human Pancreas ◽  
Parasympathetic Innervation ◽  
Tissue Extracts ◽  
Normal Human ◽  
The Impact

The glial cell line-derived neurotrophic factor (GDNF) family member neurturin (NRTN) and its receptor GFRα2 play a deciding role in the normal development of pancreatic parasympathetic innervation. In this study, we aimed at investigating the role of NRTN/GFRα2 axis in pancreatic neuropathy in human chronic pancreatitis (CP). Expression of NRTN/GFRα2 was compared between normal human pancreas (NP) and CP tissues via immunohistochemistry, immunoblotting, and quantitative RT-PCR and correlated to abdominal pain sensation. To elucidate the impact of NRTN in pancreatic neuroplasticity, neuronal phenotype and glial density were quantified via an in vitro neuroplasticity assay in dissociated newborn rat dorsal root ganglia (DRG) cultured 1) in CP tissue extracts depleted from NRTN, 2) in NP, 3) in untreated CP tissue extracts, and 4) CP extracts in which nerve growth factor, glial cell derived-neurotrophic factor, or TGF-β1was depleted. NRTN and GFRα2 were highly upregulated in CP, especially in intrapancreatic nerves and the extracellular matrix. CP tissue demonstrated increased amounts of mature multimeric NRTN and elevated levels of GFRα2. The noticeable neurotrophic effect of CP tissue extracts on DRG neurons was diminished upon blockade of NRTN from these extracts. However, blockade of NRTN from CP extracts did not influence the density of DRG glia cells. In conclusion, the NRTN/GFRα2 axis is activated during the course of CP and represents a major key player in the reactive neural alterations in CP. This is the first study to provide functional evidence for the contribution of neurotrophic factors to neuroplasticity in CP.

scholarly journals Inhibition of microsomal lipid peroxidation by glutathione and glutathione transferases B and AA. Role of endogenous phospholipase A2

1984 ◽  
Vol 220 (1) ◽  
pp. 243-252 ◽  
Author(s):  
K H Tan ◽  
D J Meyer ◽  
J Belin ◽  
B Ketterer
Keyword(s):  
Lipid Peroxidation ◽  
Phospholipase A2 ◽  
Rat Liver ◽  
Inhibitory Activity ◽  
Liver Microsomes ◽  
Supernatant Fraction ◽  
Rat Liver Microsomes ◽  
Microsomal Lipid Peroxidation ◽  
Soluble Supernatant

Lipid peroxidation in vitro in rat liver microsomes (microsomal fractions) initiated by ADP-Fe3+ and NADPH was inhibited by the rat liver soluble supernatant fraction. When this fraction was subjected to frontal-elution chromatography, most, if not all, of its inhibitory activity could be accounted for by the combined effects of two fractions, one containing Se-dependent glutathione (GSH) peroxidase activity and the other the GSH transferases. In the latter fraction, GSH transferases B and AA, but not GSH transferases A and C, possessed inhibitory activity. GSH transferase B replaced the soluble supernatant fraction as an effective inhibitor of lipid peroxidation in vitro. If the microsomes were pretreated with the phospholipase A2 inhibitor p-bromophenacyl bromide, neither the soluble supernatant fraction nor GSH transferase B inhibited lipid peroxidation in vitro. Similarly, if all microsomal enzymes were heat-inactivated and lipid peroxidation was initiated with FeCl3/sodium ascorbate neither the soluble supernatant fraction nor GSH transferase B caused inhibition, but in both cases inhibition could be restored by the addition of porcine pancreatic phospholipase A2 to the incubation. It is concluded that the inhibition of microsomal lipid peroxidation in vitro requires the consecutive action of phospholipase A2, which releases fatty acyl hydroperoxides from peroxidized phospholipids, and GSH peroxidases, which reduce them. The GSH peroxidases involved are the Se-dependent GSH peroxidase and the Se-independent GSH peroxidases GSH transferases B and AA.

scholarly journals Direct Interaction of ATP7B and LC3B Proteins Suggests a Cooperative Role of Copper Transportation and Autophagy

2021 ◽  
Author(s):  
Supansa Pantoom ◽  
Adam Pomorski ◽  
Katharina Huth ◽  
Christina Hund ◽  
Janine Petters ◽  
...  
Keyword(s):  
Direct Interaction ◽  
Copper Metabolism ◽  
Central Protein ◽  
Potential Binding ◽  
Normal Human ◽  
Autophagy Pathway ◽  
Interaction Regions ◽  
Cellular Copper

Macroautophagy/autophagy plays an important role in cellular copper clearance. The means by which the copper metabolism and autophagy pathways interact mechanistically is vastly unexplored. Dysfunctional ATP7B, a copper-transporting ATPase, is involved in the development of monogenic Wilson disease, a disorder characterized by disturbed copper transport. Using in silico prediction, we found that ATP7B contains a number of potential binding sites for LC3, a central protein in autophagy pathway, so-called LC3 interaction regions (LIRs). The conserved LIR3, located at the C-terminal end of ATP7B, was found to directly interact with LC3B in vitro. Replacing the two conserved hydrophobic residues W1452 and L1455 of LIR3 significantly reduced interaction. Furthermore, autophagy was induced in normal human hepatocellular carcinoma cells (HepG2) leading to enhanced colocalization of ATP7B and LC3B on the autophagosome membranes. By contrast, HepG2 cells deficient of ATP7B (HepG2 ATP7B-/-) showed autophagy deficiency at elevated copper condition. This phenotype was complemented by heterologous ATP7B expression. These findings suggest a cooperative role of ATP7B and LC3B in autophagy-mediated copper clearance.

scholarly journals Glioma malignancy is linked to interdependent and inverse AMOG and L1 adhesion molecule expression

BMC Cancer ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Qiong Jiang ◽  
Qing Xie ◽  
Chengliang Hu ◽  
Zhai Yang ◽  
Peizhi Huang ◽  
...  
Keyword(s):  
Adhesion Molecules ◽  
Glioma Cells ◽  
Tissue Microarrays ◽  
Human Gliomas ◽  
Glial Tumors ◽  
Therapeutic Choice ◽  
Degree Of Malignancy ◽  
Normal Human

Abstract Background Gliomas account for the majority of primary human brain tumors and remain a challenging neoplasm for cure due to limited therapeutic options. Cell adhesion molecules play pivotal roles in the growth and progression of glial tumors. Roles of the adhesion molecules on glia (AMOG) and L1CAM (L1) in glioma cells have been shown to correlate with tumorigenesis: Increased expression of L1 and decreased expression of AMOG correlate with degree of malignancy. Methods We evaluated the interdependence in expression of these molecules by investigating the role of AMOG in vitro via modulation of L1 expression and analyzing apoptosis and cell senescence of glioma cells. Results Immunohistochemical staining of normal human cortical and glioma tissue microarrays demonstrated that AMOG expression was lower in human gliomas compared to normal tissue and is inversely correlated with the degree of malignancy. Moreover, reduction of AMOG expression in human glioblastoma cells elevated L1 expression, which is accompanied by decreased cell apoptosis as well as senescence. Conclusion AMOG and L1 interdependently regulate their expression levels not only in U-87 MG cells but also in U251 and SHG44 human glioma cell lines. The capacity of AMOG to reduce L1 expression suggests that methods for increasing AMOG expression may provide a therapeutic choice for the management of glial tumors with high expression of L1.

CIAPIN1 is a potential target for apoptosis of multiple myeloma

2019 ◽  
Vol 9 (9) ◽  
pp. 1106-1111
Author(s):  
Xiao-Bo Wang ◽  
Le-Ping Yan ◽  
Li-Hua Yuan ◽  
Bo Lu ◽  
Dong-Jun Lin ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Colony Formation ◽  
Bone Marrow Cells ◽  
Xenograft Model ◽  
Soft Agar ◽  
Normal Human ◽  
Related Proteins

This study firstly aimed to reveal the gene expression differences of CIAPIN1 between myelomas cells from bone marrow cells of multiple myeloma patients and normal human, and subsequently investigate the regulation role of this gene on tumorigenicity ability of multiple myeloma (MM) cell line U266 via in vitro colony formation and in vivo xenograft studies. RT-PCR results obtained from 18 MM patients and 10 health people showed that the expression of CIAPIN1 gene was 4 times higher in normal human compared to MM patients. Besides, CIAPIN1 siRNA (si-CIAPIN1) transfected U266 cells presented higher proliferation ratio and superior colony forming ability than U266 cells and U266 cells transfected with non-coding siRNA (controls) evaluated by CCK8 test and soft agar colony formation assay, respectively. In a mice MM xenograft model, the si-CIAPIN1 transfected U266 cells induced the biggest tumor compared to the controls. Furthermore, CIAPIN1 overexpressed U266 cells were developed and compared with the si-CIAPIN1 transfected U266 cells to study the role of CIAPIN1 in the production of apoptosis related proteins in U266 cells. Results indicated that CIAPIN1 facilitated apoptosis promoting proteins expression in U266 cells, such as upregulation of BAX, BAK, Bcl-xs and BIM, and downregulation of p38, PKC, Bcl-2 and Bcl-xl proteins. Therefore, CIAPIN1 can be a potential suppression target gene in multiple myeloma.

Influence of humoral and volume factors on altered osmoregulation of normal human pregnancy

1990 ◽  
Vol 258 (4) ◽  
pp. F900-F907 ◽  
Author(s):  
J. M. Davison ◽  
E. A. Shiells ◽  
P. R. Philips ◽  
M. D. Lindheimer
Keyword(s):  
Hypertonic Saline ◽  
Water Immersion ◽  
Plasma Osmolality ◽  
Late Pregnancy ◽  
Human Pregnancy ◽  
Pregnancy And Postpartum ◽  
Normal Human ◽  
Central Volume ◽  
In Pregnancy

These studies were designed to characterize mechanisms leading to decreased plasma osmolality (Posmol) and osmotic thresholds (T) for arginine vasopressin (AVP) release (TAVP) and thirst (Tthirst) in pregnancy. First, the influence of the pregnancy hormone, human chorionic gonadotrophin (hCG), was tested in six nonpregnant women who received hypertonic saline during the luteal phase of the menstrual cycle on two occasions (randomly allocated), once after 15,000 IU of hCG when Posmol, TAVP, and Tthirst decreased 6, 5, and 5 mosmol/kgH2O, respectively (P less than 0.01). In contrast, hCG pretreatment of males (n = 6) had no significant effect. Next, the role of decreased effective vascular volume (underfilling) was evaluated in seven women undergoing hypertonic saline infusion in the presence and absence of head-out water immersion (randomly allocated) during early and late pregnancy and postpartum. Posmol, TAVP, and Tthirst were not influenced by immersion and remained 10 mosmol/kgH2O lower in pregnancy (P less than 0.01). Central redistribution of intravascular volume consistently lowered hematocrit and rate of rise of PAVP per unit increment in Posmol (P less than 0.01). Although these data failed to support the hypothesis that the osmoregulatory change in human pregnancy is attributable to decrements in effective central volume (underfill), they do suggest that hCG may play a role.

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