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Salhab M.,CNRS Physiology of Reproduction and Behaviors | Papillier P.,CNRS Physiology of Reproduction and Behaviors | Perreau C.,CNRS Physiology of Reproduction and Behaviors | Guyader-Joly C.,UNCEIA Departement Recherche et Developpement | And 3 more authors.
Reproduction, Fertility and Development | Year: 2010

β-Thymosins are small proteins that regulate the actin cytoskeleton and are involved in cell motility, differentiation, the induction of metalloproteinases, in anti-inflammatory processes and tumourigenesis. However, their roles in the ovary have not yet been elucidated. Using transcriptomics and real time reverse transcriptionpolymerase chain reaction validation, the present study demonstrates that thymosin β-4 (TMSB4) and thymosin β-10 (TMSB10) are upregulated in bovine cumulus cells (CCs) during in vitro maturation of cumulusoocyte complexes (COCs) in parallel with an increase in mRNA expression of HAS2, COX2 and PGR genes. Using immunocytochemistry, both proteins were found to be localised mainly in granulosa cells, CCs and oocytes, in both the cytoplasm and nucleus, as well as being colocalised with F-actin stress fibres in CCs. Using different maturation mediums, we showed that the expression of TMSB10, but not TMSB4, was positively correlated with COC expansion and progesterone secretion and negatively correlated with apoptosis. Immunofluorescence, coupled with terminal deoxyribonucleotidyl transferase-mediated dUTPdigoxigenin nick end-labelling (TUNEL), demonstrated the absence of TMSB4 and/or TMSB10 in apoptotic cells. TMSB10 expression was higher in COCs matured in vivo than in vitro, and differences related to the age of the animal were observed. TMSB4 and/or TMSB10 expression was unchanged, whereas HAS2 overexpressed in CCs from oocytes that developed to the blastocyst stage in vitro compared with those that did not. Thus, TMSB4 and/or TMSB10 ovarian expression patterns suggest that these two thymosins may be involved in cumulus modifications during maturation. © 2010 CSIRO. Source

Gamarra G.,UNCEIA Departement Recherche et Developpement | Ponsart C.,UNCEIA Departement Recherche et Developpement | Lacaze S.,MIDATEST | Le Guienne B.,UNCEIA Departement Recherche et Developpement | And 6 more authors.
Livestock Science | Year: 2014

This study was designed to determine the effects of dietary propylene glycol (PG; Propypact®, DIFAGRI, France) on blood metabolites, metabolic and reproductive hormones and follicular growth in 10 dairy heifers. Treatments consisted of (1) 1.1kg of sugar beet pulp (Control), (2) 150g PG (PG150) and (3) 300g PG (PG300). Each heifer received the three treatments in different randomized orders. A standard hay/concentrate diet, formulated to allow a daily liveweight gain of 900g/day, was given at 8:00 and the dietary treatments were given at 16:00 from Days 1 to 13 of the oestrous cycle following induced oestrus (Day 0). Oestrus induction treatment consisted of a subcutaneous 3mg norgestomet implant inserted for 9 days combined with GnRH treatment (i.m.) at implant insertion. Two days before implant removal, 500μg cloprostenol was administered i.m. Blood samples were collected by jugular venipuncture every 2h for 24h on Days 0 and 13 to measure plasma insulin, glucose, β-hydroxybutyrate (BHB) and urea concentrations. Blood samples were also collected to measure insulin-like growth factor-1 (IGF-1), oestradiol, progesterone concentrations on Days 2, 6, 9 and 12 and AMH (Anti-Müllerian hormone) on Days 0, 2, 6, 9 and 12. On Days 2, 6, 9 and 12 ovarian follicular growth was evaluated; the total number of follicles and their diameters were recorded and classed (2-3mm, 4-7mm, and >8mm). Results were analysed by repeated-measures ANOVA. There were no treatment, day and interaction effects on average urea concentrations while there were some differences between Days 0 and 13 for insulin, glucose and BHB. Insulin and glucose concentrations were higher on Day 13 compared to Day 0 and the opposite was observed for BHB. There were treatment, time and interaction effects on glucose and BHB concentrations measured over 24h on Day 13; glucose concentrations were higher (P<0.05) at 4:00, 8:00, 12:00, 16:00 and 20:00h, whereas BHB concentrations were lower (P<0.05) at 20:00 and 22:00h in the PG300 group compared to the control and PG150 groups. There were treatment, day and interaction effects on IGF-1 and progesterone concentrations, and the number of small follicles. PG150 resulted in higher progesterone concentrations on Days 9 and 12, and more small follicles on Day 2 compared to Control. AMH concentrations were unaffected by day of oestrous cycle and dietary treatment. However a negative correlation was observed between pre-PG distribution insulin and AMH (r=-0.47, P<0.05). These results indicate that short-term dietary PG supplementation affects circulating concentrations of metabolites and metabolic hormones, increases progesterone concentrations and the number of small follicles. Propylene glycol supplementation may be effective in improving oocyte production when combined with hormonal treatments to stimulate follicular growth for superovulation or ovum-pick up. © 2014 Elsevier B.V. Source

Gamarra G.,UNCEIA Departement Recherche et Developpement | Ponsart C.,UNCEIA Departement Recherche et Developpement | Lacaze S.,MIDATEST | Le Guienne B.,UNCEIA Departement Recherche et Developpement | And 7 more authors.
Reproduction, Fertility and Development | Year: 2015

Rapid genetic improvement in cattle requires the production of high numbers of embryos of excellent quality. Increasing circulating insulin and/or glucose concentrations improves ovarian follicular growth, which may improve the response to superovulation. The measurement of anti-Müllerian hormone (AMH) can help predict an animal's response to superovulation treatment. The aim of the present study was to investigate whether increasing circulating insulin concentrations, through propylene glycol (PG) drenches, could improve in vitro embryo production in oestrus-synchronised superovulated heifers with different AMH profiles. Holstein heifers were grouped according to pre-experimental AMH concentrations as low (L) or high (H). The PG drench increased circulating insulin and glucose concentrations and reduced β-hydroxybutyrate and urea concentrations compared with the control group. AMH was a good predictor of follicle and oocyte numbers at ovum pick-up (OPU), and of oocyte and embryo quality (AMH H>AMH L). PG in the AMH H group increased the number of follicles and blastocyst quality above that in the control group, but did not improve these parameters in the AMH L group. These results indicate that short-term oral PG supplementation modifies an animal's metabolic milieu and is effective in improving in vitro embryo production, after superovulation-OPU, more markedly in heifers with high rather than low AMH concentrations. © 2015 CSIRO. Source

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