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1.
Nutrients ; 16(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38542816

RESUMO

The meat derived from mammals such as cows, sheep, and pigs is commonly referred to as red meat. Recent studies have shown that consuming red meat can activate the immune system, produce antibodies, and subsequently develop into tumors and cancer. This is due to the presence of a potential carcinogenic compound in red meat called N-ethanol neuraminic acid (Neu5Gc). Neu5Gc is a common sialic monosaccharide in mammals, synthesized from N-acetylneuraminic acid (Neu5Ac) in the body and typically present in most mammals. However, due to the lack of the CMAH gene encoding the cytidine 5'-monophosphate Neu5Ac hydroxylase, humans are unable to synthesize Neu5Gc. Compared to primates such as mice or chimpanzees, the specific loss of Neu5Gc expression in humans is attributed to fixed genome mutations in CMAH. Although Neu5Gc cannot be produced, it can be introduced from specific dietary sources such as red meat and milk, so it is necessary to use mice or chimpanzees that knock out the CMAH gene instead of humans as experimental models. Further research has shown that early pregnancy factor (EPF) has the ability to regulate CD4+T cell-dependent immune responses. In this study, we established a simulated human animal model using C57/BL6 mice with CMAH gene knockout and analyzed the inhibitory effect of EPF on red meat Neu5Gc-induced CMAH-/- C57/BL6 mouse antibody production and chronic inflammation development. The results showed that the intervention of EPF reduced slow weight gain and shortened colon length in mice. In addition, EPF treatment significantly reduced the levels of anti Neu5Gc antibodies in the body, as well as the inflammatory factors IL-6 and IL-1ß, TNF-α and the activity of MPO. In addition, it also alleviated damage to liver and intestinal tissues and reduced the content of CD4 cells and the expression of B cell activation molecules CD80 and CD86 in mice. In summary, EPF effectively inhibited Neu5Gc-induced antibody production, reduced inflammation levels in mice, and alleviated Neu5Gc-induced inflammation. This will provide a new re-search concept and potential approach for developing immunosuppressants to address safety issues related to long-term consumption of red meat.


Assuntos
Chaperonina 10 , Neoplasias , Proteínas da Gravidez , Carne Vermelha , Fatores Supressores Imunológicos , Feminino , Animais , Humanos , Camundongos , Bovinos , Suínos , Ovinos , Pan troglodytes , Formação de Anticorpos , Primatas , Inflamação , Mamíferos
2.
Int J Mol Sci ; 24(20)2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37895099

RESUMO

Today, there is strong and diversified evidence that in humans at least 50% of early embryos do not proceed beyond the pre-implantation period. This evidence comes from clinical investigations, demography, epidemiology, embryology, immunology, and molecular biology. The purpose of this article is to highlight the steps leading to the establishment of pregnancy and placenta formation. These early events document the existence of a clear distinction between embryonic losses during the first two weeks after conception and those occurring during the subsequent months. This review attempts to highlight the nature of the maternal-embryonic dialogue and the major mechanisms active during the pre-implantation period aimed at "selecting" embryos with the ability to proceed to the formation of the placenta and therefore to the completion of pregnancy. This intense molecular cross-talk between the early embryo and the endometrium starts even before the blastocyst reaches the uterine cavity, substantially initiating and conditioning the process of implantation and the formation of the placenta. Today, several factors involved in this dialogue have been identified, although the best-known and overall, the most important, still remains Chorionic Gonadotrophin, indispensable during the first 8 to 10 weeks after fertilization. In addition, there are other substances acting during the first days following fertilization, the Early Pregnancy Factor, believed to be involved in the suppression of the maternal response, thereby allowing the continued viability of the early embryo. The Pre-Implantation Factor, secreted between 2 and 4 days after fertilization. This linear peptide molecule exhibits a self-protective and antitoxic action, is present in maternal blood as early as 7 days after conception, and is absent in the presence of non-viable embryos. The Embryo-Derived Platelet-activating Factor, produced and released by embryos of all mammalian species studied seems to have a role in the ligand-mediated trophic support of the early embryo. The implantation process is also guided by signals from cells in the decidualized endometrium. Various types of cells are involved, among them epithelial, stromal, and trophoblastic, producing a number of cellular molecules, such as cytokines, chemokines, growth factors, and adhesion molecules. Immune cells are also involved, mainly uterine natural killer cells, macrophages, and T cells. In conclusion, events taking place during the first two weeks after fertilization determine whether pregnancy can proceed and therefore whether placenta's formation can proceed. These events represent the scientific basis for a clear distinction between the first two weeks following fertilization and the rest of gestation. For this reason, we propose that a new nomenclature be adopted specifically separating the two periods. In other words, the period from fertilization and birth should be named "gestation", whereas that from the completion of the process of implantation leading to the formation of the placenta, and birth should be named "pregnancy".


Assuntos
Implantação do Embrião , Placenta , Animais , Humanos , Gravidez , Feminino , Placenta/fisiologia , Implantação do Embrião/fisiologia , Endométrio , Útero , Embrião de Mamíferos/fisiologia , Mamíferos
3.
Biotech Histochem ; 97(2): 79-89, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33641543

RESUMO

Multipotent mesenchymal stromal cells (MSC) can be isolated from many tissues, including bone marrow (BM) and placenta (PL). Human placenta can be obtained readily without invasive procedures. There may be differences, however, in differentiation capacity and immunomodulation by MSC isolated from BM or PL. The early pregnancy factor (heat shock protein 10; EPF/Hsp10) is a small protein that exhibits immunomodulatory properties. We compared BM- and PL-MSC, and assessed their efficacy for suppressing T-cell proliferation in vitro and the role of EPF/Hsp10 in this process. PL-MSC were collected from whole placenta after removal of the amniotic and chorionic membranes followed by serial enzymatic digestions. The PL-MSC were compared to BM-MSC, obtained from healthy donors. Differentiation capacity, cytokine secretion, expression and secretion of immunomodulatory molecules, immunophenotype and real time proliferation were assessed using cytokine arrays, ELISA assays, flow cytometry, immunohistochemical staining and western blotting. Whereas BM-MSC consisted of a homogeneous cell population with strong expression of mesenchymal markers, PL-MSC consisted of a mixed population of cells with variable CD73, CD90 and CD105 expression. PL-MSC exhibited a significantly greater proliferation rate than BM-MSC. The presence of both stem cells and more mature cells in the PL-MSC cultures resulted in decreased differentiation capacity and reduced efficacy of immune suppression in co-cultures with T-cells. Although robust intracellular expression of EPF/Hsp10 in both BM- and PL-MSC was observed, secretion of the protein in response to immune activating stimuli remained below detectable levels. Secretion of pro-inflammatory cytokines was significantly greater in BM-MSC than PL-MSC, whereas no difference was observed in the secretion of hematopoiesis supporting growth factors. Development of culture methods for isolation of pure populations of PL-MSC may improve the quality of the product and reproducibility of results.


Assuntos
Medula Óssea , Células-Tronco Mesenquimais , Células da Medula Óssea , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Feminino , Humanos , Placenta , Gravidez , Reprodutibilidade dos Testes
4.
Linacre Q ; 87(1): 60-77, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32431449

RESUMO

OBJECTIVES: This review sought to evaluate the evidence for embryo formation during intrauterine device (IUD) use, to articulate how often embryo loss occurs in well-designed studies, and to comment on other bodies of literature suggestive of postfertilization mechanisms of action of IUDs. METHODS: The MEDLINE, EMBASE, and Ovid databases were searched for English-language studies of markers of pregnancy in IUD users in May 2018. Studies of human chorionic gonadotropin (hCG) were subjected to quality assessment based on the US Preventive Services Task Force quality tool. Bias of studies assessing pregnancy in other ways was assessed on a study-to-study basis. RESULTS: In all, 1,073 studies were identified and 138 were read in detail. Twenty-three studies of ß-hCG, 4 studies of direct observation of embryos in fallopian tubes, 2 studies of pregnancy-specific binding globulin (PSBG), and 1 study of heat-shock protein 10 (Hsp10) or chaperonin 10 were included. In all studies considered together, 7.3 percent of IUD users had evidence of fertilization and pregnancy failure. In good-quality studies, 4.5 percent had evidence of fertilization and pregnancy failure. DISCUSSION: There are no randomized trials of embryo formation and loss in IUD users compared with noncontracepting controls. Studies of ß-hCG span a large spectrum of quality, but several good-quality studies exist, which support embryo formation and loss in IUD users. Evidence of embryos found in tubes is moderate and evidence of PSBG and Hsp10 elaboration was limited, but these are also concerning for embryo formation and loss. CONCLUSION: There is good-quality evidence of embryo formation and loss in IUD users. Studies are inconsistent, and the stated conclusions of several papers inaccurately diminish postfertilization evidence of embryo formation. To better assess the rate of embryo loss in IUD users compared with non-users, future research should include well-designed prospective trials and less subjective assessments of embryos in fallopian tubes. SUMMARY: A systematic review was carried out examining the English-language literature in the MEDLINE, EMBASE, and Ovid databases for evidence of embryo formation and loss during IUD use. In all, 1,073 studies were identified and 138 were read. There are no randomized trials and evidence ranges in quality, but evidence for the embryo formation and loss in 4.5 percent of IUD users exists in good-quality research. Further research is needed to compare embryo loss in IUD users to loss in controls.

5.
Linacre Q ; 82(1): 18-33, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25698840

RESUMO

There has been much debate regarding levonorgestrel emergency contraception's (LNG-EC's) method of action since 1999 when the Food and Drug Administration first approved its use. Proponents of LNG-EC have argued that they have moral certitude that LNG-EC works via a non-abortifacient mechanism of action, and claim that all the major scientific and medical data consistently support this hypothesis. However, newer medical data serve to undermine the consistency of the non-abortifacient hypothesis and instead support the hypothesis that preovulatory administration of LNG-EC has significant potential to work via abortion. The implications of the newer data have important ramifications for medical personnel, patients, and both Catholic and non-Catholic emergency room protocols. In the future, technology such as the use of early pregnancy factor may have the potential to quantify how frequently preovulatory LNG-EC works via abortion. Lay Summary: How Plan B (levonorgestrel emergency contraception) works has been vigorously debated ever since the Food and Drug Administration approved it in 1999. Many doctors and researchers claim that it has either no-or at most-an extremely small chance of working via abortion. However, the latest scientific and medical evidence now demonstrates that levonorgestrel emergency contraception theoretically works via abortion quite often. The implications of the newer data have important ramifications for medical personnel, patients, and both Catholic and non-Catholic emergency room rape protocols.

6.
Theriogenology ; 83(5): 832-9, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25542459

RESUMO

Early pregnancy factor has been identified as a 10-kDa extracellular homolog of heat shock protein 10 (Hsp10). Hsp10 has been detected during early pregnancy in serum of mice, sheep, pigs, horses, cows, and humans by the rosette inhibition test. Hsp10 has also been associated with several neoplastic and autoimmune diseases. The goal of the present study was to determine if Hsp10 could be detected in the early equine embryo through the use of immunohistochemistry and quantitative real-time PCR. Additionally, analysis of systemically harvested peripheral blood mononuclear cells (PBMCs) from both pregnant and nonpregnant mares was evaluated to determine expression levels of HSP10. Embryos were collected from Quarter Horse mares by uterine lavage at either 8 or 25 days after ovulation. Collection and separation of PBMCs occurred on Day 8 for both pregnant and nonpregnant mares. Immunohistochemistry revealed cytoplasmic localization of HSP10 throughout the single layer of ectodermal cells forming the trophoblast in Day-8 embryos. Day-25 embryos demonstrated intense localization focally along the apical border of ectodermal cells forming the trophoblast layer of the developing chorion. There was no nuclear staining in either embryonic population. Quantitative real-time PCR detected the presence of mRNA for HSP10 in both 8- and 25-day equine embryos. Day-25 embryos exhibited an elevated degree of expression (P = 0.006) compared with the 8-day embryos for HSP10. Endometrial samples did not display any significant difference in degree of expression for HSP10 (P = 0.10). Finally, PBMCs from pregnant mares demonstrated elevated (P = 0.03) expression of HSP10 compared to the nonpregnant mares on Day 8 of the estrous cycle. This study confirmed the presence of HSP10 protein and mRNA expression of HSP10 in equine embryos at two maturation stages. Additionally, the presence of increased gene expression within PBMCs of pregnant mares suggests communication, possibly leading to necessary immunomodulatory effects between the embryo and mare.


Assuntos
Chaperonina 10/metabolismo , Endométrio/metabolismo , Cavalos/metabolismo , Leucócitos Mononucleares/metabolismo , Animais , Chaperonina 10/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Cavalos/embriologia , Imuno-Histoquímica/veterinária , Gravidez , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária
7.
Biotech Histochem ; 90(1): 14-24, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24989882

RESUMO

Early pregnancy factor (EPF) is an immunosuppressant that promotes maternal immune system tolerance of the allogenic fetus. Little is known about localization of this factor in different tissues and nothing has been reported about localization in swine reproductive and placental tissues. We determined the concentration of EPF in serum of gilts and porcine placenta conditioned medium (PPCM). We also analyzed the expression of EPF in different reproductive tissues of pregnant gilts at 10, 30, 60 and 90 days of pregnancy. EPF concentration in serum and PPCM was determined by western blot and densitometry. EPF expression in reproductive tissue was assessed by immunohistochemistry. The highest concentration of EPF was observed at 30 days in serum and PPCM; the concentration was higher in PPCM than in serum at the stages we evaluated. All reproductive tissues from the gestational stages analyzed showed specific labeling of EPF, but this labeling did not appear in non-pregnant gilts. At 30 days pregnancy, the EPF expression in the ovary was predominantly in follicular lutein cells, probably owing to its function as a luteotrophic factor. In the oviduct, EPF was expressed in unciliated secretory epithelial cells and in the cilia of ciliated cells. In the placenta, EPF was expressed in the fetal portion (mesoderm chorioallantois and epithelium of endoderm). EPF acts as an autocrine and paracrine growth factor for the trophoblast during the peri-implantation period.


Assuntos
Chaperonina 10/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Ovário/metabolismo , Placenta/metabolismo , Proteínas da Gravidez/metabolismo , Fatores Supressores Imunológicos/metabolismo , Útero/metabolismo , Animais , Células Epiteliais/metabolismo , Epitélio/metabolismo , Feminino , Imuno-Histoquímica/métodos , Gravidez , Reprodução/fisiologia
8.
Int J Womens Health ; 3: 391-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22140327

RESUMO

A new progesterone antagonist, ulipristal has been made available as an emergency contraceptive. Ulipristal's major mechanism of action as an emergency contraceptive has been ascribed to its ability to delay ovulation beyond the life span of the sperm. This paper analyzes the potential action of ulipristal (1) when unprotected intercourse and administration of ulipristal occur outside the fertility window and (2) when unprotected intercourse and administration of ulipristal occur at or within 24 hours of ovulation. When unprotected intercourse and the use of a single low dose of ulipristal occur outside of the fertility window, ulipristal behaves like a placebo. When unprotected intercourse and the use of a single low dose of ulipristal occur within the fertility window but before ovulation, ulipristal behaves like an emergency contraceptive by delaying ovulation and thereby preventing fertilization. When unprotected intercourse and the administration of ulipristal occur at or within 24 hours of ovulation, then ulipristal has an abortifacient action. It is proposed that the abortifacient mechanism of a low dose of ulipristal taken after fertilization but before implantation is due to the ability of ulipristal to block the maternal innate immune system to become immunotolerant to the paternal allogenic embryo. Progesterone's critical immunotolerant actions involving early pregnancy factor, progesterone-induced blocking factor, and uterine natural killer cells are compromised by ulipristal.

9.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-221874

RESUMO

Early pregnancy factor(EPF) is believed to be a pregnancy-associated immunosuppressivepolypeptide which might inhibit the function of maternal lymphocyte during pregnancy. Thephysiological role of EPF in human pregnancy has remained controversal. The purposes of thisstudy are to investigate whether EPF determinations have prognostic value in women withthreatened abortion, and to evaluate usefulness in diagnosing early pregnancy and in predictingthe outcome of embryo transferred in vitro fertilization-embryo transfer(IVF-ET) program.EPF activity was measured by a recently developed, micro rosette inhibition test in sera from76 normal pregnant women, 25 normal healthy women with tubal ligation, 58 women withtherapeutic surgical abortion(n=18) or threatened abortion(n=40) and 29 IVF-ET patients. Rosetteinhibition titer>or=3 was defined as an index for the presence of EPF activity. EPF activity wasundetectable in sera of normal healthy women with tubal ligation and in sera taken before ET.In normal pregnancy EPF was detected in 88~92% of sera during the first and second trimesterand almost disappeared in the third trimester. Surgical therapeutic abortion in the firsttrimester lead to disappearance of EPF activity in 92.3% of cases second day after procedure.The sensitivity of the EPF assay in predicting the outcome in pregnant women with threatenedabortion was 88.0% and the specificity was found to be 86.7%. In patients who became pregnantafter IVF-ET procedure EPF activity was detected in 85.7% of sera on the 5th day andin all sera on the 12th day. In 80.0%(9/13) sera of patients who failed to become pregnant afterET, EPT activity was detected on the 5th day but 17(94.4%) of 18 sera was proved to benegative for EPF activity on the 12th day. These data suggest that EPF assay by micro rosetteinhibition test may be useful in monitoring the embryo after ET, in dignosing early pregnancyand in predicting the outcome in women with threatened abortion.


Assuntos
Feminino , Humanos , Gravidez , Aborto Terapêutico , Ameaça de Aborto , Estruturas Embrionárias , Linfócitos , Terceiro Trimestre da Gravidez , Gestantes , Sensibilidade e Especificidade , Esterilização Tubária
10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-534919

RESUMO

An immunosuppressive early pregnancy factor (EPF) present in the serum of pregnent women, between 3 and 6 weeks of gestation, was isolated and purified using ion-exchange chromatography, affinity chromatography and gel filtration techniq(?) The serum samples and chromatographic fractions were measured for EPF activity using rossette inhibition test and hCG content by radioimmunoassay. The result showed that the column eluates (?) gel filtration exhibited no hCG (3. 1 ng/ ml). The fraction containing the bulk of EPF on SDS polyacrylamide gel electrophoresis revealed the presence of polypeptide bands of molecular weight at 24 kDa and 41 kDa respectively.

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