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1.
Theriogenology ; 176: 26-34, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34564014

RESUMO

Some bulls with apparently normal semen quality yield unacceptably low pregnancy rates. We hypothesised that a differential uterine immunological response to sperm from high and low fertility bulls may contribute to these differences. The experimental model used was heifer follicular phase uterine explants incubated with frozen-thawed sperm from high and low fertility bulls (3-5 replicates per experiment). Inflammatory gene expression of IL1A, IL1B, IL6, TNFA and CXCL8 were assessed by qPCR and IL1-ß and IL-8 were quantified in explant supernatants by ELISA. Neutrophil binding affinity to sperm from high and low fertility bulls was also assessed. There was a significant up-regulation of IL1A, IL1B and TNFA from frozen-thawed sperm, irrespective of fertility status, compared to the unstimulated control. This response was confirmed at the protein level, with an increase of IL-1ß and IL-8 protein concentrations by 5 and 2.7 fold, respectively (P < 0.05). Although no significant differences in the inflammatory response at the gene or protein level were evident between high and low fertility bulls, more sperm from low compared to high fertility bulls bound to neutrophils (P < 0.05). Using bulls of unknown fertility, cauda epididymal sperm (CES) plus seminal plasma (SP) upregulated IL6 (P < 0.05) but there was no upregulation of any inflammatory gene expression for CES alone. Overall, this ex vivo study demonstrated an upregulation of inflammatory gene expression in the uterus in response to frozen-thawed bull sperm. While there was no difference between sperm from high and low fertility bulls, there was a greater binding affinity of low fertility sperm by neutrophils.


Assuntos
Análise do Sêmen , Preservação do Sêmen , Animais , Bovinos , Criopreservação/veterinária , Feminino , Fertilidade , Masculino , Gravidez , Sêmen , Análise do Sêmen/veterinária , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides , Útero
2.
Placenta ; 35(2): 85-91, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24418702

RESUMO

INTRODUCTION: Exposure to low-dose radiation is widespread and attributable to natural sources. However, occupational, medical, accidental, and terrorist-related exposures remain a significant threat. Information on radiation injury to the feto-placental unit is scant and largely observational. We hypothesized that radiation causes trophoblast injury, and alters the expression of injury-related transcripts in vitro or in vivo, thus affecting fetal growth. METHODS: Primary human trophoblasts (PHTs), BeWo or NCCIT cells were irradiated in vitro, and cell number and viability were determined. Pregnant C57Bl/6HNsd mice were externally irradiated on E13.5, and placentas examined on E17.5. RNA expression was analyzed using microarrays and RT-qPCR. The experiments were repeated in the presence of the gramicidin S (GS)-derived nitroxide JP4-039, used to mitigate radiation-induced cell injury. RESULTS: We found that survival of in vitro-irradiated PHT cell was better than that of irradiated BeWo trophoblast cell line or the radiosensitive NCCIT mixed germ cell tumor line. Radiation altered the expression of several trophoblast genes, with a most dramatic effect on CDKN1A (p21, CIP1). Mice exposed to radiation at E13.5 exhibited a 25% reduction in mean weight by E17.5, and a 9% reduction in placental weight, which was associated with relatively small changes in placental gene expression. JP4-039 had a minimal effect on feto-placental growth or on gene expression in irradiated PHT cells or mouse placenta. DISCUSSION AND CONCLUSION: While radiation affects placental trophoblasts, the established placenta is fairly resistant to radiation, and changes in this tissue may not fully account for fetal growth restriction induced by ionizing radiation.


Assuntos
Desenvolvimento Fetal/efeitos da radiação , Regulação da Expressão Gênica no Desenvolvimento/efeitos da radiação , Radiação Ionizante , Trofoblastos/efeitos da radiação , Animais , Linhagem Celular , Feminino , Retardo do Crescimento Fetal/etiologia , Humanos , Camundongos , Óxidos de Nitrogênio/uso terapêutico , Placenta/efeitos da radiação , Gravidez , Lesões por Radiação/tratamento farmacológico , Irradiação Corporal Total/efeitos adversos
3.
J Clin Endocrinol Metab ; 79(1): 205-10, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8027228

RESUMO

Recombinant human (rh) insulin-like growth factor-I (IGF-I) is a potential therapy for individuals with severe insulin resistance, but its efficacy, mechanism of action, or duration of effect for these patients have not been explored fully. Two subjects with the type A phenotype of severe insulin resistance without insulin receptor mutations were investigated to assess insulin secretion, insulin action, and carbohydrate tolerance before and after 3-4 weeks of rhIGF-I treatment (100 micrograms/kg, sc, twice daily). Tests included 24-h glucose and insulin profile (modal day), standardized liquid meal with Sustacal, insulin tolerance test, insulin suppression test, and iv glucose tolerance test. In subject 1, the 24-h mean blood glucose level was 8.1 +/- 2.7 mmol/L before rhIGF-I treatment and fell to 4.2 +/- 0.9 mmol/L during rhIGF-I treatment. The pretreatment 24-h mean serum insulin level was 10,251 +/- 8,849 pmol/L and fell to 1533 +/- 1198 pmol/L. Fasting blood glucose fell from 4.4 to 3.4 mmol/L, and 2-h blood glucose after Sustacal administration fell from 10.3 to 5.3 mmol/L. Fasting serum insulin declined from 808 to 246 pmol/L, and the 2-h serum insulin level fell from 5,491 to 3,443 pmol/L. After bolus iv insulin injection (0.15 U/kg), glucose fell by 20% before rhIGF-I treatment and by 67% during rhIGF-I treatment. The steady state plasma glucose level was 18.2 +/- 0.7 before rhIGF-I and 10.8 +/- 0.1 mmol/L during rhIGF-I. In subject 2, fasting blood glucose fell from 12.0 to 7.4 mmol/L and 24-h mean blood glucose fell from 12.7 +/- 1.9 to 6.6 +/- 1.3 mmol/L. Twenty-four-hour mean serum insulin fell from 892 +/- 635 to 521 +/- 293 pmol/L, and first phase insulin secretion was restored during the iv glucose tolerance test. We conclude that sc rhIGF-I can reduce blood glucose effectively in selected patients with the type A phenotype of severe insulin resistance who have diabetes mellitus. rhIGF-I also can enhance insulin sensitivity, as assessed by a decrease in endogenous insulin levels, normalization of response to iv insulin, and a reduced steady state plasma glucose. The cellular mechanisms for these effects remain undefined.


Assuntos
Glicemia/metabolismo , Resistência à Insulina , Fator de Crescimento Insulin-Like I/uso terapêutico , Insulina/farmacologia , Adulto , Feminino , Teste de Tolerância a Glucose , Humanos , Insulina/metabolismo , Secreção de Insulina , Cinética , Proteínas Recombinantes/uso terapêutico , Síndrome
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