Analysis of prostaglandins formed from endogenous and exogenous arachidonic acid in homogenates of human reproductive tissues

Thromboxane (TX) synthesis of washed human platelets pretreated with high concentrations of thrombin (0.5-2.0 U/ml) for 20 sec is significantly reduced upon further thrombin stimulation. Compared to controls (tyrode-pretreated platelets), thrombin-preactivated platelets recover normal TX synthesis following exposure to exogenous arachidonic acid (AA) indicating that short-time thrombin treatment does not inactivate platelet cyclooxygenase or TX synthetase (Blood 63: 858, 1984). To evaluate whether the reduced TX synthesis upon -the second thrombin exposure is due to depletion of their AA precursor pool, thrombin-pretreated platelets and tyrode-pretreated platelets (5×108/ml) were resuspended in autologous ACD plasma and incubated at 37°C with 0.2 μCi 14C-AA (20 μM) for 60 to 90 min in the presence of PGE1 (10 μM). Mean platelet uptake of 14C-AA (disappearance of radioactivity from the supernatant) was 12+3 nmoles AA/109 platelets and did not differ significantly between thrombin-pretreated platelets and controls. Thrombin-pretreated platelets released 10% or 4.5% of their 14c-activity upon further exposure to thrombin (2 U/ml) or collagen (8 μg/ml), respectively. The release from control platelets (15% with thrombin, 6.5% with collagen) did not differ from that of thrombin-pretreated platelets. However, even after incubation in ACD plasma, thrombin-pretreated platelets continued to form significantly less TXB2 (5.0±1.6 nmoles/109 platelets) than controls (9.7±2.2 nmoles/109 platelets, p< 0.05). These data indicate that the reduced capacity of thrombin-pretreated platelets is due neither to a depletion of the endogenous AA pool nor to an inactivation of cyclooxygenase or TX synthetase. The reduced TX synthesis capacity may be caused by a modification, destruction or desensitization of the platelet thrombin receptor as a consequence of the preceding thrombin stimulation.

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Automated Classification of Protein Subcellular Location Patterns on Images of Human Reproductive Tissues

Intelligent Science and Intelligent Data Engineering - Lecture Notes in Computer Science ◽

10.1007/978-3-642-36669-7_32 ◽

2013 ◽

pp. 254-262

Author(s):

Fan Yang ◽

Ying-Ying Xu ◽

Hong-Bin Shen

Keyword(s):

Subcellular Location ◽

Automated Classification ◽

Protein Subcellular Location ◽

Reproductive Tissues ◽

Location Patterns ◽

Human Reproductive

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The Expression of miRNAs in Human Ovaries, Oocytes, Extracellular Vesicles, and Early Embryos: A Systematic Review

Cells ◽

10.3390/cells8121564 ◽

2019 ◽

Vol 8 (12) ◽

pp. 1564 ◽

Cited By ~ 7

Author(s):

Albert Salas-Huetos ◽

Emma R. James ◽

Kenneth I. Aston ◽

Timothy G. Jenkins ◽

Douglas T. Carrell ◽

...

Keyword(s):

Systematic Review ◽

Extracellular Vesicles ◽

Mirna Expression ◽

Observational Studies ◽

Reproductive Function ◽

Human Reproduction ◽

Reproductive Tissues ◽

Early Embryos ◽

Human Reproductive

The recent discovery of microRNAs (miRNAs) in human reproductive tissues and cells indicates a possible functional role in reproductive function. However, the studies published to date in female reproductive tissues/cells and embryos are inconclusive and sometimes controversial. In order to update the knowledge of this field, the present study aimed to discuss, through a systematic review, the role of miRNAs in female human reproduction and early embryogenesis. We conducted a systematic review of the published literature in MEDLINE and EMBASE databases through June 2018 (plus a complementary search until July 2019), in accordance with the PRISMA guidelines. We have included descriptive and observational studies, in which fertile/infertile women were well-defined. The primary outcome was the miRNA expression in ovaries, oocytes, extracellular vesicles, and embryos. We identified 25,204 articles, of which 28 were selected for qualitative analysis: 18 in ovaries and extracellular vesicles, three in oocytes, and seven in embryos. The present systematic review of descriptive and observational studies demonstrates that aberrant miRNA expression in female reproductive tissues/cells and embryos is related with infertility and embryogenesis errors. The expression of specific miRNAs, particularly in extracellular vesicles, may be used in the future as biomarkers of infertility and prognostic tools of embryo development.

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