RESUMO
One-carbon metabolites (OCM) are metabolites and cofactors which include folate, vitamin B12, methionine, and choline that support methylation reactions. The objectives of this study were to investigate the effects of moderate changes in maternal body weight gain in combination with OCM supplementation during the first 63 d of gestation in beef cattle on (1) B12 and folate concentrations in maternal serum (2) folate cycle intermediates in maternal and fetal liver, allantoic fluid (ALF), and amniotic fluid (AMF) and (3) metabolites involved in one-carbon metabolism and related metabolic pathways in maternal and fetal liver. Heifers were either intake restricted (RES) and fed to lose 0.23 kg/d, or fed to gain 0.60 kg/d (CON). Supplemented (+â OCM) heifers were given B12 and folate injections weekly and fed rumen-protected methionine and choline daily, while non-supplemented (-OCM) heifers were given weekly saline injections. These two treatments were combined in a 2â ×â 2 factorial arrangement resulting in 4 treatments: CON-OCM, CONâ +â OCM, RES-OCM, and RESâ +â OCM. Samples of maternal serum, maternal and fetal liver, ALF, and AMF were collected at slaughter on day 63 of gestation. Restricted maternal nutrition most notably increased (./â ≤â 0.05) the concentration of vitamin B12 in maternal serum, 5,10-methylenetetrahydrofolate and 5,10-methenyltetrahydrofolate in maternal liver, and cystathionine in the fetal liver; conversely, maternal restriction decreased (Pâ =â 0.05) 5,10-methylenetetrahydrofolate concentration in fetal liver. Supplementing OCM increased (Pâ ≤â 0.05) the concentrations of maternal serum B12, folate, and folate intermediates, ALF and AMF 5-methyltetrahydrofolate concentration, and altered (Pâ ≤â 0.02) other maternal liver intermediates including S-adenosylmethionine, dimethylglycine, cystathionine Glutathione reduced, glutathione oxidized, taurine, serine, sarcosine, and pyridoxine. These data demonstrate that OCM supplementation was effective at increasing maternal OCM status. Furthermore, these data are similar to previously published literature where restricted maternal nutrition also affected maternal OCM status. Altering OCM status in both the dam and fetus could impact fetal developmental outcomes and production efficiencies. Lastly, these data demonstrate that fetal metabolite abundance is highly regulated, although the changes required to maintain homeostasis may program altered metabolism postnatally.
Maternal stresses that occur during pregnancy, such as restricted nutrition, can impact the developmental outcomes of the offspring in a process known as developmental programming. This programming can occur through epigenetics, which involves changes in fetal gene expression and can occur through the addition of methyl groups to DNA. These changes regulate gene transcription in the offspring and can alter offspring health, efficiency, and life-long outcomes. One-carbon metabolites (OCM), which are nutrients like the amino acid methionine and the vitamins B12, folate, and choline, act as intermediates or cofactors for the donation of methyl groups to DNA. This study investigated the effects of differing maternal rates of gain along with OCM supplementation during early gestation on OCM and related metabolite concentrations in the dam and fetus. We found that supplementing OCM to beef heifers increased maternal OCM and related metabolite concentrations and fetal fluid OCM concentrations. We also found that low maternal gain increased maternal serum and liver OCM concentrations. We can conclude from these findings that both maternal rate of gain and OCM supplementation can impact maternal OCM concentrations at day 63 of gestation and further research is needed to see if those maternal impacts will affect the developing fetus or calf later in its life.
Assuntos
Suplementos Nutricionais , Ácido Fólico , Fígado , Metionina , Vitamina B 12 , Animais , Feminino , Metionina/administração & dosagem , Metionina/metabolismo , Bovinos , Gravidez , Ácido Fólico/administração & dosagem , Ácido Fólico/metabolismo , Ácido Fólico/sangue , Vitamina B 12/administração & dosagem , Vitamina B 12/sangue , Vitamina B 12/metabolismo , Fígado/metabolismo , Feto/metabolismo , Dieta/veterinária , Colina/administração & dosagem , Colina/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Líquido Amniótico/metabolismo , Líquido Amniótico/químicaRESUMO
The objective of this study was to determine the dose-dependent response of one-carbon metabolite (OCM: methionine, choline, folate, and vitamin B12) supplementation on heifer dry matter intake on fixed gain, organ mass, hematology, cytokine concentration, pancreatic and jejunal enzyme activity, and muscle hydrogen peroxide production. Angus heifers (nâ =â 30; body weight [BW]â =â 392.6â ±â 12.6 kg) were individually fed and assigned to one of five treatments: 0XNEG: total mixed ration (TMR) and saline injections at days 0 and 7 of the estrous cycle, 0XPOS: TMR, rumen-protected methionine (MET) fed at 0.08% of the diet dry matter, rumen-protected choline (CHOL) fed at 60 g/d, and saline injections at days 0 and 7, 0.5X: TMR, MET, CHOL, 5-mg B12, and 80-mg folate injections at days 0 and 7, 1X: TMR, MET CHOL, 10-mg vitamin B12, and 160-mg folate at days 0 and 7, and 2X: TMR, MET, CHOL, 20-mg vitamin B12, and 320-mg folate at days 0 and 7. All heifers were estrus synchronized but not bred, and blood samples were collected on days 0, 7, and at slaughter (day 14) during which tissues were collected. By design, heifer ADG did not differ (Pâ =â 0.96). Spleen weight and uterine weight were affected cubically (Pâ =â 0.03) decreasing from 0XPOS to 0.5X. Ovarian weight decreased linearly (Pâ <â 0.01) with increasing folate and B12 injection. Hemoglobin and hematocrit percentage were decreased (Pâ <â 0.01) in the 0.5X treatment compared with all other treatments. Plasma glucose, histotroph protein, and pancreatic α-amylase were decreased (Pâ ≤â 0.04) in the 0.5X treatment. Heifers on the 2X treatment had greater pancreatic α-amylase compared with 0XNEG and 0.5X treatment. Interleukin-6 in plasma tended (Pâ =â 0.08) to be greater in the 0XPOS heifers compared with all other treatments. Lastly, 0XPOS-treated heifers had reduced (Pâ ≤â 0.07) hydrogen peroxide production in muscle compared with 0XNEG heifers. These data imply that while certain doses of OCM do not improve whole animal physiology, OCM supplementation doses that disrupt one-carbon metabolism, such as that of the 0.5X treatment, can induce a negative systemic response that results in negative effects in both the dam and the conceptus during early gestation. Therefore, it is necessary to simultaneously establish an optimal OCM dose that increases circulating concentrations for use by the dam and the conceptus, while avoiding potential negative side effects of a disruptive OCM, to evaluate the long-term impacts of OCM supplementation of offspring programming.
The feeding of one-carbon metabolites (including methionine and B vitamins) has been shown to improve fetal growth and milk production in species such as mice, sheep, and dairy cattle. Extending this to beef cattle around the time of breeding is a growing area of research. Our group previously determined that one-carbon metabolite supplementation to beef heifers altered the abundance of circulating methionine-folate cycle intermediates in a dose-dependent manner. Therefore, we aimed to determine a whole-body response to one-carbon metabolite supplementation in heifers by measuring the effects on specific physiological systems as well as a total systemic response. We determined that treatments that negatively altered the methionine-folate cycle yielded a fundamental negative whole-body response to supplementation.
Assuntos
Ração Animal , Colina , Dieta , Suplementos Nutricionais , Ácido Fólico , Metionina , Vitamina B 12 , Animais , Feminino , Bovinos/fisiologia , Bovinos/metabolismo , Metionina/administração & dosagem , Metionina/metabolismo , Metionina/farmacologia , Dieta/veterinária , Vitamina B 12/administração & dosagem , Vitamina B 12/metabolismo , Vitamina B 12/farmacologia , Ácido Fólico/administração & dosagem , Ácido Fólico/metabolismo , Ração Animal/análise , Colina/administração & dosagem , Colina/metabolismoRESUMO
To investigate the effects of nutrient restriction and one-carbon metabolite (OCM) supplementation (folate, vitamin B12, methionine, and choline) on fetal small intestine weight, vascularity, and cell proliferation, 29 (n = 7 ± 1 per treatment) crossbred Angus beef heifers (436 ± 42 kg) were estrous synchronized and conceived by artificial insemination with female sexed semen from a single sire. Then, they were allotted randomly to one of four treatments in a 2 × 2 factorial arrangement with the main factors of nutritional plane [control (CON) vs. restricted feed intake (RES)] and OCM supplementation [without OCM (-OCM) or with OCM (+OCM)]. Heifers receiving the CON level of intake were fed to target an average daily gain of 0.45 kg/day, which would allow them to reach 80% of mature BW by calving. Heifers receiving the RES level of intake were fed to lose 0.23 kg/heifer daily, which mimics observed production responses in heifers that experience a diet and environment change during early gestation. Targeted heifer gain and OCM treatments were administered from d 0 to 63 of gestation, and then all heifers were fed a common diet targeting 0.45 kg/d gain until d 161 of gestation, when heifers were slaughtered, and fetal jejunum was collected. Gain had no effect (p = 0.17) on the fetal small intestinal weight. However, OCM treatments (p = 0.02) displayed less weight compared to the -OCM groups. Capillary area density was increased in fetal jejunal villi of RES - OCM (p = 0.02). Vascular endothelial growth factor receptor 2 (VEGFR2) positivity ratio tended to be greater (p = 0.08) in villi and was less in the crypts (p = 0.02) of the RES + OCM group. Cell proliferation decreased (p = 0.02) in villi and crypts of fetal jejunal tissue from heifers fed the RES + OCM treatment compared with all groups and CON - OCM, respectively. Spatial cell density increased in RES - OCM compared with CON + OCM (p = 0.05). Combined, these data show OCM supplementation can increase expression of VEGFR2 in jejunal villi, which will promote maintenance of the microvascular beds, while at the same time decreasing small intestine weight and crypt cell proliferation.
RESUMO
We hypothesized that restricted maternal nutrition and supplementation of one-carbon metabolites (OCM; methionine, folate, choline, and vitamin B12) would affect placental vascular development during early pregnancy. A total of 43 cows were bred, and 32 heifers successfully became pregnant with female calves, leading to the formation of four treatment groups: CON - OCM (nâ =â 8), CONâ +â OCM (nâ =â 7), RES - OCM (nâ =â 9), and RESâ +â OCM (nâ =â 8). The experimental design was a 2â ×â 2 factorial, with main factors of dietary intake affecting average daily gain: control (CON; 0.6 kg/d ADG) and restricted (RES; -0.23 kg/d ADG); and OCM supplementation (+OCM) in which the heifers were supplemented with rumen-protected methionine (7.4 g/d) and choline (44.4 g/d) and received weekly injections of 320 mg of folate and 20 mg of vitamin B12, or received no supplementation (-OCM; corn carrier and saline injections). Heifers were individually fed and randomly assigned to treatment at breeding (day 0). Placentomes were collected on day 63 of gestation (0.225 of gestation). Fluorescent staining with CD31 and CD34 combined with image analysis was used to determine the vascularity of the placenta. Images were analyzed for capillary area density (CAD) and capillary number density (CND). Areas evaluated included fetal placental cotyledon (COT), maternal placental caruncle (CAR), whole placentome (CARâ +â COT), intercotyledonary fetal membranes (ICOT, or chorioallantois), intercaruncular endometrium (ICAR), and endometrial glands (EG). Data were analyzed with the GLM procedure of SAS, with heifer as the experimental unit and significance at Pâ ≤â 0.05 and a tendency at Pâ >â 0.05 and Pâ <â 0.10. Though no gainâ ×â OCM interactions existed (Pâ ≥â 0.10), OCM supplementation increased (Pâ =â 0.01) CAD of EG, whereas nutrient restriction tended (Pâ <â 0.10) to increase CAD of ICOT and CND of COT. Additionally, there was a gainâ ×â OCM interaction (Pâ <â 0.05) for CAD within the placentome and ICAR, such that RES reduced and supplementation of RES with OCM restored CAD. These results indicate that maternal rate of gain and OCM supplementation affected placental vascularization (capillary area and number density), which could affect placental function and thus the efficiency of nutrient transfer to the fetus during early gestation.
In cowcalf production, periods of poor forage availability or quality can result in nutrient restriction during pregnancy. Previous studies have shown that even moderate maternal feed restriction during pregnancy, including very early in pregnancy, has profound effects on fetal and placental development, potentially having lasting impacts on calf growth and body composition later in life. One-carbon metabolites (OCM) in the diet are biomolecules required for methylation reactions and participate in the regulation of gene expression. Our objective was to evaluate the effects of nutrient restriction and OCM supplementation (specifically methionine, choline, folate, and vitamin B12) on placental vascular development during early pregnancy. Proper placental vascular development is necessary for healthy pregnancy outcomes, reflected by normal birth weight and healthy offspring. Our results indicated that maternal rate of gain and OCM supplementation affect placental vascularization, which could affect placental function and thereby fetal development throughout gestation. In the context of beef cattle production, our study sheds light on strategies that could enhance placental vascular development during early pregnancy. However, it is essential to recognize the nuances in our data, highlighting the need for further research to fully comprehend these intricate processes.
Assuntos
Complexo Ferro-Dextran , Placenta , Feminino , Gravidez , Animais , Bovinos , Melhoramento Vegetal , Metionina/farmacologia , Racemetionina , Carbono , Colina/farmacologia , Suplementos Nutricionais , Ácido Fólico/farmacologia , Vitamina B 12/farmacologia , Dieta/veterináriaRESUMO
Adequate maternal nutrition is key for proper fetal development and epigenetic programming. One-carbon metabolites (OCM), including vitamin B12, folate, choline, and methionine, play a role in epigenetic mechanisms associated with developmental programming. This study investigated the presence of B12 and folate in maternal serum, allantoic fluid (ALF), and amniotic fluid (AMF), as well as how those concentrations in all three fluids correlate to the concentrations of methionine-folate cycle intermediates in heifers receiving either a control (CON) or restricted (RES) diet for the first 50 d of gestation and fetal hepatic gene expression for methionine-folate cycle enzymes. Angus cross heifers (nâ =â 43) were estrus synchronized, bred via artificial insemination with semen from a single sire, and randomly assigned to one of two nutrition treatments (CONâ =â 20, RESâ =â 23). Heifers were ovariohysterectomized on either day 16 (nâ =â 14), 34 (nâ =â 15), or 50 of gestation (nâ =â 14), where samples of maternal serum (nâ =â 42), ALF (nâ =â 29), and AMF (nâ =â 11) were collected and analyzed for concentrations of folate and B12. Concentrations of B12 and folate in ALF were greater (Pâ <â 0.05) in RES compared to CON. For ALF, folate concentrations were also greater (Pâ <â 0.01) on day 34 compared to day 50. There was a significant (Pâ =â 0.04) nutritionâ ×â fluid interaction for B12 concentrations where concentrations were greatest in restricted ALF, intermediate in control ALF, and lowest in CON and RES serum and AMF. Folate concentrations were greatest (Pâ <â 0.01) in ALF, intermediate in serum, and lowest in AMF. Additionally, positive correlations (Pâ <â 0.05) were found between ALF and AMF folate concentrations and AMF concentrations of methionine, serine, and glycine. Negative correlations (Pâ <â 0.05) between AMF folate and serum homocysteine were also observed. Both positive and negative correlations (Pâ <â 0.05) depending on the fluid evaluated were found between B12 and methionine, serine, and glycine concentrations. There was a downregulation (Pâ =â 0.05) of dihydrofolate reductase and upregulation (Pâ =â 0.03) of arginine methyltransferase 7 gene expression in RES fetal liver samples compared with CON fetal liver on day 50. Combined, these data show restricted maternal nutrition results in increased B12 and folate concentrations present in fetal fluids, and increased expression of genes for enzymes within one-carbon metabolism.
When pregnant cattle have restricted access to feed or specific nutrients, calf development can be affected, and the degree of impairment depends, at least partially, on timing, duration, and severity of the limitations. A biochemical pathway present in cells that can be affected by limited nutrition is one-carbon metabolism. This pathway is related to epigenetics, which regulates gene expression or the turning on and off of genes. Two important vitamins in one-carbon metabolism are vitamins B12 and folate. By understanding the amounts of those vitamins available to the developing calf, we can gain better insight into the regulation and potential avenues of improvement of calf growth and development. In this study, we found a nutrient restricted maternal diet increased the amount of B12 and folate in calf allantoic and amniotic fluids. We also found that folate and B12 were correlated to the presence of other nutrients in serum, allantoic fluid, and amniotic fluid. In addition, we found that a protein methylating gene in one-carbon metabolism had increased expression in calves from heifers receiving limited nutrition. This study is an important step in understanding how the nutrients available to a pregnant heifer during gestation affects nutrients available to the conceptus.
Assuntos
Ácido Fólico , Metionina , Gravidez , Animais , Bovinos , Feminino , Vitamina B 12 , Dieta/veterinária , Racemetionina , Fígado/metabolismo , Glicina , Serina , Carbono/metabolismoRESUMO
The objective of this study was to determine the dose of folate and vitamin B12 in beef heifers fed rumen protected methionine and choline required to maintain increased B12 levels and intermediates of the methionine-folate cycle in circulation. Angus heifers (nâ =â 30; BWâ =â 392.6â ±â 12.6 kg) were individually fed and assigned to one of five treatments: 0XNEG: Total mixed ration (TMR) and saline injections at day 0 and 7 of the estrous cycle, 0XPOS: TMR, rumen protected methionine (MET) fed at 0.08% of the diet DM, rumen protected choline (CHOL) fed at 60 g/d, and saline injections at day 0 and 7, 0.5X: TMR, MET, CHOL, 5 mg B12, and 80 mg folate at day 0 and 7, 1X: TMR, MET CHOL, 10 mg vitamin B12, and 160 mg folate at day 0 and 7, and 2X: TMR, MET, CHOL, 20 mg B12, and 320 mg folate at day 0 and 7. All heifers were estrus synchronized but not bred, and blood was collected on day 0, 2, 5, 7, 9, 12, and 14 of a synchronized estrous cycle. Heifers were slaughtered on day 14 of the estrous cycle for liver collection. Serum B12 concentrations were greater in the 0.5X, 1X, and 2X, compared with 0XNEG and 0XPOS on all days after treatment initiation (Pâ <â 0.0001). Serum folate concentrations were greater for the 2X treatment at day 5, 7, and 9 of the cycle compared with all other treatments (Pâ ≤â 0.05). There were no differences (Pâ ≥â 0.19) in hepatic methionine-cycle or choline analyte concentrations by treatment. Concentrations of hepatic folate cycle intermediates were always greater (Pâ ≤â 0.04) in the 2X treatment compared with the 0XNEG and 0XPOS heifers. Serum methionine was greater (Pâ =â 0.04) in the 0.5X and 2X heifers compared with 0XNEG, and S-adenosylhomocysteine (SAH) tended (Pâ =â 0.06) to be greater in the 0.5X heifers and the S-adenosylmethionine (SAM):SAH ratio was decreased (Pâ =â 0.05) in the 0.5X treatment compared with the 0XNEG, 0XPOS, and 2X heifers. The hepatic transcript abundance of MAT2A and MAT2B were decreased (Pâ ≤â 0.02) in the 0.5X heifers compared with the 0XNEG, 0XPOS, and 2X heifers. These data support that beef heifers fed rumen protected methionine and choline require 20 mg B12 and 320 mg folate once weekly to maintain increased concentrations of B12 and folate in serum. Furthermore, these data demonstrate that not all supplementation levels are equal in providing positive responses, and that some levels, such as the 0.5X, may result in a stoichiometric imbalance in the one-carbon metabolism pathway that results in a decreased SAM:SAH ratio.
The strategic inclusion of one-carbon metabolites, which include vitamins and minerals that are found in human prenatal vitamins, to beef cattle feeding and management protocols during the periconceptual period (the time around breeding) is a novel concept. Therefore, this study aimed to identify the feeding and injection doses of one-carbon metabolites in beef heifers to maintain increased circulating concentrations of one-carbon metabolites for use as a model from which other studies could base their treatments on. We determined that daily feeding of methionine and choline at 0.08% of dry matter and 60 g/d, respectively, and administration of vitamin B12 and folate at 20 mg and 320 mg once per week, respectively resulted in sustained elevated concentrations of one-carbon metabolites.