There is ample evidence on the importance of maternal nutrition during pregnancy on fetal and offspring development. In ruminant females, the pool of oocytes is complete and definitive before birth, based on the resting reserve of primordial follicles established during fetal life, which represent the lifespan supply for the female's fertilisable oocytes, whereas in males, although the production of spermatozoa is a continuous process throughout post-pubertal life. Sertoli cells, which play a central role in the development of a functional testis, proliferate during pre- and post-natal life, coordinating testicular development. Both male and female fertility may, therefore, be affected by the maternal environment, but studies on the effects of developmental nutritional conditions on reproductive function and fertility, both in males and females, are relatively scarce. In humans, intrauterine growth retardation has been associated with abnormal ovarian development, characterised by a decreased volume of primordial follicles in the ovarian cortical tissue in girls, and a higher incidence of cryptorchidism in boys, with subsequent low sperm counts in adulthood. Age at puberty and gonadotropin and inhibin B plasma concentrations are also affected. Animal studies suggest both in males and females that maternal undernutrition during pregnancy may affect pituitary response to GnRH and gonadal development and function, depending on the timing and magnitude of the undernutrition. Excess nutrition, which is often associated with intrauterine growth retardation in domestic species, induces effects on the onset of puberty and both testicular and ovarian function, maybe through the observed reduction in fetal growth. This review addresses the influence of maternal nutrition on offspring reproductive function using examples in humans and animals, with particular focus on ruminants.
Effects of parity (primiparous, PRIM vs multiparous, MULT) and litter size (singletons, SING vs twins, TWIN) on metabolic profiles from 1 wk before lambing to the end of lactation were studied in 48 Lacaune dairy ewes reared in confinement during most of the year and grazed on improved pastures at the end of lactation (summer). Another group of 48 ewes was incorporated during the milking period (ie, from 1 wk after weaning), to measure the effects of milking frequency (1 vs 2 milkings per day) on intake, milk production and composition, and body energy usage. Thus, in a 2 × 2 × 2 factorial design, ewes (n = 96) were allocated to homogeneous groups according to body weight (BW) and body condition score (BCS) and were monitored from late pregnancy to late lactation as a function of parity (PRIM, n = 48; MULT, n = 48), litter size (LSi) (SING, n = 40; TWIN, n = 56) and daily milking frequency (FREQ; milked once, ONE; n = 48; or twice, TWO; n = 48). Individual BW, BCS, plasma metabolites, and metabolic hormones were measured regularly (ie, 9 consecutive sampling dates). The BW was higher in MULT but no differences because of LSi or FREQ were detected at the intra-parity group level. The BCS was higher in MULT and in ewes with SING throughout the experiment. The latter was related to the demands for body reserves mobilization, as expressed by higher nonesterified fatty acids and β-hydroxybutyrate concentrations in ewes with TWIN from late pregnancy to weaning (35 d postpartum) in both PRIM and MULT ewes. This was consistent with higher insulin in MULT and higher triiodothyronine, leptin and insulin-like growth factor 1 in ewes with SING during this period. Differences in energy balance because of FREQ were evident after interpretation of plasma nonesterified fatty acids, glucose, insulin, and leptin concentration during the milking period. At similar feed intakes, ewes in ONE were in positive balance with regard to TWO. Overall, clear effects of parity, LSi, physiological states, and FREQ on metabolic profiles were found because of differences in nutrient partitioning when combining these experimental factors. Without considering FREQ, changes in metabolic measures in milking period were marginal compared with the periparturient adjustments performed until weaning to compensate energy deficiencies.
Throughout an entire year, 41 Romane ewes reared in an extensive rangeland were used to investigate temporal changes in body reserves (BRs) and profiles of related metabolites and metabolic hormones. Ewes were allocated to homogeneous groups according to BW and BCS and were distributed by parity (primiparous [PRIM], n = 21; multiparous [MULT], n = 20) and litter size (LSi; lambing singletons [SING], n = 21 or TWINS, n = 20). The feeding system was based on rotational grazing of rangeland paddocks and progressive supplementation with hay, silage, and barley at late pregnancy during the winter. Individual BW, BCS, plasma NEFA, β-hydroxybutyrate (β-OHB), glucose, insulin, leptin, and triiodothyronine (T3) were monitored at −56, −12, 8, 49, 76, 107, 156, 195, 216, 246, and 301 d relative to lambing. The BR mobilization was observed from late pregnancy to the end of suckling and varied as a function of the ewe energy balance but also because of transitions from fertilized to native rangeland paddocks and by supplementation. Contrarily, BR accretion occurred from weaning, during the dry-off, and until the start of the next pregnancy. Lipolysis was well reflected by NEFA, β-OHB, and T3 kinetics. Mean BW (but not mean BCS) was affected by parity (MULT > PRIM), whereas both BW and BCS were influenced by LSi (SING > TWINS) but only for MULT. The most drastic BW loss was observed during the mid-suckling period (49 d in milk [DIM]) in all ewes. The lack of effects of LSi in PRIM but not in MULT was also evident in the majority of blood plasma kinetics, which were affected (P < 0.0001) by physiological stage in all ewes. A tendency to ketosis (β-OHB) was found in ewes nursing TWINS around lambing, irrespective of parity. Glucose concentrations were greater during suckling and dry-off, and a peak (0.96 ± 0.05 g/L) was attained at 156 DIM in MULT nursing TWINS. The highest plasma leptin concentration was observed during the start and the middle of the next pregnancy in MULT (107–216 DIM; 9.6 ± 0.44 ng/mL). In all ewes the physiological stage affected T3, which was affected by LSi just in MULT (from late pregnancy, MULT by SING > MULT by TWINS; 99.91 vs 85.52 ng/dL) and during suckling (111.7 ± 4.18 ng/dL). Lamb BW was affected at birth and weaning by parity (MULT > PRIM) and LSi (SING > TWINS). Overall, temporal changes in BR were directly affected by the transition of physiological states and feeding levels, whereas individual responses were predetermined by parity. In MULT, the reactivity and magnitude of response was influenced by LSi. The whole set of parameters allowed us to detect sensitive and critical periods throughout the entire annual cycle. We thus identified opportunities for improved nutritional management, for example, during physiological states usually underestimated such as early and mid-pregnancy. This work indicates the applicability of long-term studies about BR dynamics in ruminants as a potential component contributing to farm economic resilience.
The objective of this study was to compare the effects of the type of Haemonchus contortus experimental infection (trickle infection, TI versus single infection, SI) on feed intake, nutrients digestibility, parasitological and haematological measures, and plasma leptin in Creole kids. The animals were infected over 2 periods (challenge 1 and challenge 2) of 6 weeks each, corresponding respectively to the primary and the secondary infection. Periods prior infection (1 week each) were considered as controls. The primary infection was realized with 35 Creole kids (18.40 ± 3.76 kg BW) housed in individual boxes and fed a hay-based diet. The secondary infection continued with 29 kids (21.90 ± 3.40 kg BW) from the initial 35. A total of 6 kids and 8 kids were slaughtered for measuring nematode burden at the end of the primary and the secondary infection, respectively. Measurements of nutrients digestibility were made at 0, 3 and 5 weeks post-infection for both challenges. Faecal egg count (FEC), blood eosinophilia and packed cell volume (PCV) were monitored weekly. Feed intake (dry matter intake, DMI) and nutrients digestibility were negatively affected by H. contortus infection only during the primary infection. Plasma leptin changed significantly over time (P = 0.0002) but was not affected by the infection type. Effect of infection type was observed only on crude protein digestibility during the primary infection, which was lower in the TI group (P < 0.01). The overall level of blood eosinophilia was significantly higher in the TI group (P < 0.0001) during both challenges. The overall FEC mean was significantly higher in the SI compared with the TI groups, during both challenges (P < 0.02). These results were related to the mean female length significantly higher in the SI group compared with the TI group during challenge 1 (P = 0.004), and the number of adult nematode significantly lower in the TI group compared with the SI group during the challenge 2 (P = 0.05). The results showed that the response of Creole kids to H. contortus experimental infection was in part dependent on the type of experimental infection. Our data suggest that plasma leptin would not be involved in the response of Creole kids against H. contortus infection, as no relationship between its plasma level and the transient reduction in voluntary feed intake observed in both groups during the primary infection was observed.
Since the first success in cloning sheep, the production of viable animals by somatic cell nuclear transfer (SCNT) has developed significantly. Cattle are by far the most successfully cloned species but, despite this, the technique is still associated with a high incidence of pregnancy failure and accompanying placental and fetal pathologies. Pre- and early post-implantation losses can affect up to 70% of the pregnancies. In the surviving pregnancies, placentomegaly and fetal overgrowth are commonly observed, but the incidence varies widely, depending on the genotype of the nuclear donor cell and differences in SCNT procedures. In all cases, the placenta is central to the onset of the pathologies. Although cellular organisation of the SCNT placenta appears normal, placental vascularisation is modified and fetal-to-maternal tissue ratios are slightly increased in the SCNT placentomes. In terms of functionality, steroidogenesis is perturbed and abnormal estrogen production and metabolism probably play an important part in the increased gestation length and lack of preparation for parturition observed in SCNT recipients. Maternal plasma concentrations of pregnancy-associated glycoproteins are increased, mostly due to a reduction in turnover rate rather than increased placental production. Placental glucose transport and fructose synthesis appear to be modified and hyperfructosemia has been observed in neonatal SCNT calves. Gene expression analyses of the bovine SCNT placenta show that multiple pathways and functions are affected. Abnormal epigenetic re-programming appears to be a key component of the observed pathologies, as shown by studies on the expression of imprinted genes in SCNT placenta.
Maternal undernutrition during gestation can condition offspring adult health, with the periconceptional period pointed out as a key period. The aim of this study was to evaluate the effects of maternal periconceptional undernutrition on pregnancy and offspring growth performance in sheep.52 Merinos d'Arles ewes were fed to requirements (control group, C), whereas 64 ewes received 50% of their dietary needs from -15 to +30 days post-conception (restricted group, R). Thereafter, both groups were fed according to needs. Maternal body weight (BW), body condition score (BCS) and Non Esterified Fatty Acids (NEFA), progesterone, leptin and cortisol plasma concentrations were monitored weekly during the restriction period and the following month, then monthly until weaning. Lambs were weighed weekly until weaning at 22 kg BW, then monthly. Plasma leptin was monitored monthly in lambs.The BW, BCS, and leptin concentrations were significantly decreased, whereas NEFA and cortisol concentrations were increased in R dams. Maximum progesterone concentration was higher in R ewes that had a high (10-25%) vs. low (0-10%) BW loss during restriction (27.9 +/- 2.59 vs. 20.8 +/- 2.00 ng/mL, P < 0.05). Overall, gestation was significantly longer in the R group (151.0 +/- 0.3 vs. 149.4 +/- 0.4 days, P < 0.001). There was no difference between groups for pregnancy rates, prolificacy, birth weight and lamb mortality, but the proportion of male lambs was significantly higher in the R group, only for singletons (16/26 vs. 9/26, P < 0.05). Lamb growth was not significantly modified by treatment. Leptin concentrations at birth were significantly lower in R vs. C males (6.15 +/- 0.13 ng/mL vs. 7.42 +/- 0.36 ng/mL, P < 0.05), whereas in females, leptin concentrations were significantly higher in R vs. C lambs at 4 mo of age (7.31 +/- 0.27 ng/mL vs. 6.41 +/- 0.29 ng/mL, P < 0.05).These results indicate that maternal periconceptional undernutrition in a hardy breed does not significantly affect lamb birth weight and growth rates, in contrast to previous reports in other breeds, suggesting that caution must be taken when extrapolating programming data between breeds and breeding conditions. (C) 2012 Elsevier Inc. All rights reserved.
Epidemiological studies in humans, as well as animal models, have shown that maternal environment at critical periods of fetal development can condition offspring adult health. Previous studies have shown effects of maternal undernutrition during early to mid gestation on Sertoli cell proliferation and seminiferous tubule diameter in male lambs of 10 months of age. Delayed follicular maturation and meiosis in female fetuses have been reported after maternal undernutrition from mating. The aim of this project was to evaluate the long-term effects of maternal periconceptional undernutrition on offspring physiology and reproductive function. Postnatal development of male offspring is presented here. Fifty-two control females of Merinos d’Arles breed (R100) were fed a normal diet adapted to their needs, and 64 restricted females (R50) received 50% of their dietary needs from 15 days before until 30 days after synchronized breeding. Thereafter, both groups were fed to meet their nutritional requirements. Males were weighed at birth and every week. Blood samples were collected monthly to monitor plasma leptin and cortisol concentrations. Organ weights were recorded at commercial slaughter (35 kg) and histological analysis was performed on testicles and adrenals. Data were analysed by ANOVA or Student’s test. Twenty-two live R100 and 34 live R50 male lambs were obtained. Gestation was significantly longer in the restricted group (P < 0.01). Growth rate, live weight, and age at slaughter were not significantly different between groups. Plasma leptin concentrations were significantly lower at birth (P < 0.001) and tended to be higher at 4 months of age (P = 0.09) in R50. There was a significant interaction between group, age, and litter size for basal cortisol concentrations: in singletons (n = 15 R50 and n = 8 R100), cortisol was significantly lower in R50 at 3 months of age (P < 0.05) and tended to be higher at 4 months whereas in twins (n = 17 R50 and n = 10 R100), cortisol was significantly lower at birth (P < 0.05) but not thereafter (triplets were not considered here because of low numbers). There was no statistical difference for carcass, testicle, or kidney weight. In contrast, carcass to live weight ratio and perirenal fat to live weight ratio were increased in all R50 (P < 0.05). Adrenal to live weight ratio tended to be increased in R50 lambs (P = 0.06). Histological examination revealed no statistical difference between groups for adrenal corticomedullary ratio, zona glomerulosa to medulla ratio, and zona fasciculata to medulla ratio. There was no significant difference for the analysis of testicular tissue (diameter and surface of seminiferous tubules). The expression of genes involved in testicular differentiation (SRY, 3β-HSD, OCT3/4, VASA, stra8, SOX9) is currently being studied by quantitative PCR and will be presented. These results confirm the effects of periconceptional undernutrition on metabolic function but so far, no effect has been demonstrated on testicular histology. Litter size seems to play an important role, because effects were different between singletons and twins.
Somatic nuclear transfer (NT) in cattle is often accompanied by severe placental anomalies, hypertrophy, and hydrallantois, which induce a high rate of pregnancy losses throughout gestation. These placental deficits are associated with an abnormal increase of the maternal plasma levels of pregnancy-associated glycoprotein (PAG), produced by the trophoblastic binucleate cells (BNC) of the placenta. The objective of this study was to analyze the origin of the abnormally elevated PAG concentrations in the peripheral circulation of NT recipients during pathological pregnancies. Concentrations of PAG were measured both in maternal blood, in chorionic and cotyledonary tissular extracts from control recipients (after artificial insemination, AI, or in vitro fertilization, IVF) and clone recipients on Day 32, Day 62, and during the third trimester of gestation. Three different radioimmunoassay (RIA) systems were used. One homologous RIA for PSP60, similar to bovine PAG-1 (PAG67kDa), and two heterologous RIA with PAG67kDa as standard and tracer, and antisera anti-caprine PAG (AS#706 and AS#708). Circulating and tissular concentrations of bovine placental lactogen (bPL), a glycoprotein also produced by BNC, were determined by RIA at the same stages. The number of BNC in the placental tissues was determined by cell counting after immunostaining with anti PSP60 antibody on tissue sections from control and NT pregnancies. Maternal plasma PAG concentrations were not different among groups on Day 32, but they were significantly higher in NT than in control pregnancies on Day 62 with all three RIA and during the third trimester with two RIA (RIA-PSP60 and RIA with AS#708). Circulating bPL concentrations were undetectable on Days 32 and 62 and were not different in the third trimester between NT and control pregnancies. Tissular amounts of PAG on total proteins were not different between the two groups at all stages studied. No difference was determined in the percentage of PSP60-positive BNC in placental tissues between controls and NT on Day 62 and during the third trimester of pregnancy. Western blots of tissular extracts from placenta showed no major molecular weight changes of PAG in NT pregnancies compared to controls. No differences in maternal circulation concentrations or tissular content of bPL were observed between control and NT pregnancies. In conclusion, the specific increase of PAG in maternal plasma concentrations during abnormal NT pregnancies do not result from a higher proportion of BNC, or an increased protein expression of PAG and could be due to changes in the composition of terminal glycosylation which result into a clearance decrease of PAG from the circulation.
Problem: Progesterone plays a central role during the maintenance of pregnancy. Our study aims to develop two hypoprogesteronic animal models using the 3beta‐HSD inhibitor trilostane during early pregnancy. Material and Methods: Trilostane or vehicle was injected s.c. in DBA/2J‐CBA/J female mice (4.5‐8.5 dpc) or in ewes (5‐16 day of pregnancy). Progesterone serum levels were assayed (mouse: 13.5 dpc; ewe: day 16). The resorption rate (RR), number of implantation sites (IS, mouse) or development of the conceptus (sheep) were analyzed. Results: Between trilostane‐treated or control females progesterone levels did not differ in the mouse but, as expected, progesterone did not rise in the sheep model. Nevertheless, ovine conceptus development was not morphologically affected nor IS or RR in the mouse model. Conclusions: our data suggest that trilostane dose was insufficient to affect the reproductive success in our animal models. A more thorough analysis is currently undertaken in order to better characterize the phenotypes.
American Journal of Reproductive ImmunologyVolume 58, Issue 3 p. 178-179 Ovine Progesterone-Induced Blocking Factor at the Feto-maternal Interface during Implantation CM Fovet, CM Fovet INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this authorS Camous, S Camous INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this authorE Poumerol, E Poumerol INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this authorMC Aubrière, MC Aubrière INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this authorC Giraud-Delville, C Giraud-Delville INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this authorM Dahirel, M Dahirel INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this author F Nolent, F Nolent INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this authorS Dubanchet, S Dubanchet INSERM U782, Clamart, France http://www.embic.orgSearch for more papers by this authorJ Szekeres-Bartho, J Szekeres-Bartho INRA, Jouy-en-Josas, France INSERM U782, Clamart, FranceSearch for more papers by this authorRG Lea, RG Lea School of Veterinary Medicine & Science, University of Nottingham, UKSearch for more papers by this authorO Sandra, O Sandra INRA, Jouy-en-Josas, France http://www.embic.org Olivier.Sandra@jouy.inra.frSearch for more papers by this author CM Fovet, CM Fovet INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this authorS Camous, S Camous INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this authorE Poumerol, E Poumerol INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this authorMC Aubrière, MC Aubrière INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this authorC Giraud-Delville, C Giraud-Delville INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this authorM Dahirel, M Dahirel INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this author F Nolent, F Nolent INRA, Jouy-en-Josas, France http://www.embic.orgSearch for more papers by this authorS Dubanchet, S Dubanchet INSERM U782, Clamart, France http://www.embic.orgSearch for more papers by this authorJ Szekeres-Bartho, J Szekeres-Bartho INRA, Jouy-en-Josas, France INSERM U782, Clamart, FranceSearch for more papers by this authorRG Lea, RG Lea School of Veterinary Medicine & Science, University of Nottingham, UKSearch for more papers by this authorO Sandra, O Sandra INRA, Jouy-en-Josas, France http://www.embic.org Olivier.Sandra@jouy.inra.frSearch for more papers by this author First published: 02 August 2007 https://doi.org/10.1111/j.1600-0897.2007.00519_7.xRead the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume58, Issue3September 2007Pages 178-179 RelatedInformation
Somatic cloning in the bovine species leads to high levels of fetal losses which occur throughout pregnancy. These losses are most often associated with fetal overgrowth, a syndrome known as large offspring syndrome (LOS), and excessive maternal plasma pregnancy serum protein 60 (PSP60), a protein similar to a pregnancy-associated glycoprotein of 67 kDa (PAG I67) produced by the bovine placenta. Predicting the outcome of pregnancies initiated from cloned embryos has become an important issue both to prevent potential harm to the mother because of excessive fetal size at birth and also to get a better understanding of the relationships between growth, differentiation and placental functions in developing cloned fetuses. Here, we report on a systematic analysis of fetal and placental development in the first trimester of pregnancy performed by ultrasonographic imaging and by measurement of the maternal concentrations of pregnancy associated glycoproteins (PAGS), using four different radioimmunoassays (RIA) (two homologous RIA systems with PSP60 and PAG I67; two heterologous RIA systems with PAG I67 as standard and tracer, and antisera anti-caprine PAGs). We showed that crown-rump length (CRL) in clones appeared smaller than controls at 35, 50 and 62 days (P<0.05). At 62 days of pregnancy, CRL in cloned fetuses that died before 90 days was smaller compared to the other cloned fetuses (P<0.05) whereas the width of the fetal sack and the biparietal diameter (BPD) was larger in fetuses that developed LOS in late gestation (P<0.05). Maternal PAGs concentrations were statistically different between controls and all clone recipients as early as Day 34, suggesting early abnormal placental glycoprotein synthesis for clone pregnancies regardless of pregnancy outcome. This work provides a practical, non-invasive tool to follow up clone pregnancies and suggests that primary growth retardation and abnormal placental function precedes excessive fetal and placental growth at later stages of pregnancy.
Ovine placental lactogen (oPL) is produced by the conceptus trophectoderm and is secreted into both the maternal and fetal circulations. The present study was designed to examine in vivo the luteotropic effect of recombinant oPL (roPL), as determined by monitoring progesterone concentration and cycle length (experiment 1), and the antioxidative and antiapoptotic effects of roPL, as determined respectively by monitoring antioxidant enzymatic activity and apoptosis in the corpus luteum (CL) of cyclic ewes (experiment 2). We also studied whether roPL is capable of stimulating progesterone secretion in vitro by cultured luteal tissue of functionally active CL obtained from day-10 cyclic ewes (experiment 3) and day-60 pregnant ewes (experiment 4). Circulating concentrations of progesterone and cycle length were not affected by treatment of ewes with 80 microg/kg body weight per day of roPL (n = 4 ewes) for 10 days beginning on day 11 post-estrus, as compared with saline-treated ewes (n = 4 ewes). Luteolysis occurred between days 15 and 16 post-estrus in the four saline-treated ewes and in 3/4 roPL-treated ewes. The activities of the key antioxidant enzymes copper-zinc superoxide dismutase (Cu,Zn-SOD), manganese SOD (Mn-SOD), glutathione peroxidase (GPX), glutathione reductase (GSR) and glutathione S-transferase (GST) were unaffected by treatment of ewes with 80 microg/kg per day of roPL (n = 4 ewes) for 3 days, between days 11 and 14 post-estrus, as compared with saline-treated ewes (n = 4 ewes). In situ TUNEL method revealed that the number of apoptotic cells was not different between the two groups of ewes. There was no significant change in progesterone secretion by explants from day-10 estrous cycle (n = 3 ewes) or day-60 pregnancy (n = 3 ewes) CL cultured with different concentrations (10, 100 and 1000 ng/ml) of roPL, whereas treatment with oLH at the concentration of 100 or 1000 ng/ml caused a significant increase in progesterone secretion by explants from day-10 estrous cycle CL (P < 0.05) and by explants from day-60 pregnancy CL (P < 0.01). In conclusion, our results demonstrate that oPL has no luteotropic and/or luteoprotective actions in sheep, either in vivo or in vitro.
Aspirin consumption has been reported to be able to reduce colorectal cancer risk in humans and in animal models of colon carcinogenesis. Although the mechanism involved in such an effect is not yet clear, both prostaglandin-dependent and -independent effects have been proposed. Using HT-29 Glc(-/+)cells, which originate from a human colon adenocarcinoma, we demonstrated in this study a dose-dependent effect of millimolar concentration of aspirin on cell growth that was concomitant with a rapid accumulation of the cells in the G0/G1 phase, followed by an accumulation in the G2/M phase and by a minor increase in the proportion of cells undergoing nuclear condensation. Cell membrane integrity and cell release into the culture medium were not affected by this treatment. The aspirin effects were apparently unrelated to prostaglandin biosynthesis inhibition, since although these cells were found to express high levels of cyclooxygenase 1 (COX-1) and low levels of COX-2 proteins, they did not produce any measurable net amounts of prostaglandins, based on both utilization of radiolabelled arachidonic acid and the radioimmunoassay of prostaglandins E2 and F2 alpha. In contrast, we identified polyamine biosynthesis as a cellular target of aspirin, since the treatment of HT-29 Glc(-/+) cells with aspirin reduced the flux of L-ornithine through ornithine decarboxylase, an effect that could not be explained by an acute action of the drug on the ornithine decarboxylase catalytic activity. Since polyamine biosynthesis is strictly necessary for HT-29 cell growth, our data suggest that reduced flux through ornithine decarboxylase may participate in the antiproliferative activity of aspirin towards colonic tumoral cells. It is concluded that in HT-29 Glc(-/+) cells that are not functional for prostaglandin production, aspirin can affect cell growth, cell cycle, and polyamine biosynthesis without affecting cell membrane integrity.
Nuclear transfer from somatic cells still has limited efficiency in terms of live calves born due to high fetal loss after transfer. In this study, we addressed the type of donor cells used for cloning in in vivo development. We used a combination of repeated ultrasonography and maternal pregnancy serum protein (PSP60) assays to monitor the evolution of pregnancy after somatic cloning in order to detect the occurrence of late-gestation losses and their frequency, compared with embryo cloning or in vitro fertilization (IVF). Incidence of loss between Day 90 of gestation and calving was 43.7% for adult somatic clones and 33.3% for fetal somatic clones, compared with 4.3% after embryo cloning and 0% in the control IVF group. Using PSP60 levels in maternal blood as a criterion for placental function, we observed that after somatic cloning, recipients that lost their pregnancy before Day 100 showed significantly higher PSP60 levels by Day 50 than those that maintained pregnancy (7.77 +/- 3.3 ng/ml vs. 2.45 +/- 0.27 ng/ml for normal pregnancies, P < 0.05). At later stages of gestation, between 4 mo and calving, mean PSP60 concentrations were significantly increased in pathologic pregnancy after somatic cloning compared with other groups (P < 0.05 by Day 150, P < 0.001 by Day 180, and P < 0.01 by Day 210). In those situations, and confirmed by ultrasonographic measurements, recipients developed severe hydroallantois together with larger placentome size. Our findings suggest that assessing placental development with PSP60 and ultrasonography will lead to better care of recipient animals in bovine somatic cloning.
PSP60 kinetic and its variation factors were studied in a beef suckling herd from 1296 peripheral concentrations recorded on 203 single and 47 twin pregnancies from the 3(rd) to the 9(th) months of gestation. Number of fetuses and parity of dam are significant factors of variation (p < 0.0001). PSP60 kinetic can be simply described using a linear model of the logconcentration against time with an homogeneous slope whatever the parity and the number of fetuses. The corresponding diagnosis of twinning can be carried out by a single PSP60 assay performed between 140 and 180 days of gestation, or using the average value of several assays performed during gestation. The values of sensitivity (predicted twin outcomes/observed twin outcomes) are then 77% and 81% respectively using those two procedures, and corresponding values of specificity (predicted single outcomes/observed single outcomes) are 76% and 77%. Predictive values of twin diagnoses (true twin predictions I expected twin outcomes) are 41% and 45% respectively. Corresponding values far single diagnoses are 93% and 94%.
This study characterised the peripheral plasma concentration of PSP-60 throughout gestation, and examined the effect of stage of gestation and foetal number on this protein in Holstein cows after non-surgical embryo transfer. Cows (n=12) were divided into two groups; Group 1 contained single embryo recipient cows (n=5), Group 2 contained twin-embryo recipient cows (n=7). Blood was collected approximately every third day from day 0 (first day of standing oestrus), then daily for the last 10 days of gestation and until one day post-partum. Two of the twin-embryo recipient cows had abnormal pregnancies, consequently data from them was considered separately. In both groups PSP-60 increased progressively from about day 20 post-oestrus to 20 days pre-partum (from 0·9 ± 0·2 to 49·7 ± 8·7 ng ml−1, and from 1·3 ± 0·6 to 115 ± 34·9 ng ml−1 (mean ± SEM), in singleton and twin-bearing groups, respectively). The mean concentrations between 20 and 10 days pre-partum increased dramatically by about six-fold (P<0·001) in singleton-bearing cows (from 49·7 ± 8·7 ng ml−1 to 2838 ± 73·7 ng ml−1) to over two-fold in twin-bearing cows (from 115 ± 34·9 ng ml−1 to 284 ± 98·2 ng ml-1). The mean concentrations of the two groups were indistinguishable between 10 days pre-parturn and parturition. Cows giving birth prematurely to stillborn calves or to a schistosomus reflexus calf exhibited abnormal PSP-60 profiles. Our findings indicate that peripheral plasma PSP-60 concentrations are correlated to the stage of gestation and foetal number, and assist in predicting foeto-placental viability.
This review considers the potential reduction of embryo mortality in vitro and in vivo in ruminants. Data on cytokines provided by different fields of reproductive immunology and biology were collated. Because of the crucial importance of the local interactions between the embryo and its dam, the expression of growth-factor and cytokine genes was analysed in the embryo proper, trophoblast, oviduct and endometrium by reverse transcriptase polymerase chain reaction in sheep and in cattle during the pre- and periimplantation periods. Many deleterious cytokines, such as tumour necrosis factor-alpha, interferon-gamma (IFN-gamma), interleukin-2 (IL-2), and beneficial cytokines, such as transforming growth factor-beta, leukaemia inhibiting factor, colony-stimulating factor-1 (CSF-1), granulocyte-macrophage CSF, IL-1, IL-3, IL-4, IL-6, IL-10 and IFN-tau appeared to be involved in embryo survival in ruminants and other species. Their administration is efficient in a murine experimental model (CBA/J x DBA/2) of embryonic and fetal mortality. For instance, recombinant ovine IFN-tau (roIFN-tau) injected at the moment of implantation drastically reduces embryonic mortality in this model. In ruminants, roIFN-tau and recombinant bovine IFN-tau are very efficient in maintaining progesterone luteal secretion in cyclic animals. The involvement of IFN-tau in the mechanisms of maternal pregnancy recognition are particularly detailed in relation to inhibition of 13,14 dihydro-15-keto-prostaglandin F2 alpha (PGFM) pulses and oxytocin uterine receptivity. A synthetic model of the anti-luteolytic effects of IFN-tau on the endometrial cell is proposed. Finally, the particular potential of serum pregnancy-specific proteins (PSPs: PSPB, PSP60, pregnancy-associated glycoprotein) for monitoring embryo survival, with examples given for cattle and sheep is underlined.
Circular RNAs (circRNAs) constitute a family of transcripts with unique structures and still largely unknown functions. Their biogenesis, which proceeds via a back-splicing reaction, is fairly well characterized, whereas their role in the modulation of physiologically relevant processes is still unclear. Here we performed expression profiling of circRNAs during in vitro differentiation of murine and human myoblasts, and we identified conserved species regulated in myogenesis and altered in Duchenne muscular dystrophy. A high-content functional genomic screen allowed the study of their functional role in muscle differentiation. One of them, circ-ZNF609, resulted in specifically controlling myoblast proliferation. Circ-ZNF609 contains an open reading frame spanning from the start codon, in common with the linear transcript, and terminating at an in-frame STOP codon, created upon circularization. Circ-ZNF609 is associated with heavy polysomes, and it is translated into a protein in a splicing-dependent and cap-independent manner, providing an example of a protein-coding circRNA in eukaryotes.
The accuracy and efficiency of pregnancy diagnoses in cattle by pregnancy serum protein (PSP60) radioimmunoassay, a progesterone radioimmunoassay or oestrus detection were compared. Blood samples were taken from 349 suckling heifers and cows (1,191 inseminations) at 28, 35, 50 and 90 d post-insemination for PSP60 determination and at 22-23 d for progesterone. Females were declared nonpregnant when plasma PSP60 concentration was lower than 0.2 ng/ml at 28, 35 and 50 d and 0.5 ng/ml at 90 d. When compared with rectal palpation at 90 d, the accuracy of positive (negative) diagnoses by progesterone assay was 80% (100%) in heifers and 75% (99%) in cows. The accuracy of positive diagnoses by PSP60 assay increased with gestation stage from 90% on d 28 in heifers (74% in cows) to 100% (99% in cows) at the time of rectal palpation. This accuracy was 84% on d 28 in cows when the interval from calving to blood sampling was higher than 115 d. Whatever the stage, the accuracy of negative diagnoses was higher than 90%. Efficiency in detecting pregnant or nonpregnant females on d 28 was equivalent to the progesterone assay. The method for detecting oestrus applied in this experiment was as efficient as the PSP60 or progesterone test at any stage of gestation. The PSP60 test is very flexible, which makes its use particularly interesting in naturally mated suckling herds because of the uncertainty regarding the date of fertilization.