Dietary l-arginine supplementation enhances placental growth and reproductive performance in sows

Suboptimal embryonic/fetal survival and growth remains a significant problem in mammals. Using a swine model, we tested the hypothesis that dietary l-arginine supplementation during gestation may improve pregnancy outcomes through enhancing placental growth and modulating hormonal secretions. Gestating pigs (Yorkshire?×?Landrace, n?=?108) were assigned randomly into two groups based on parity and body weight, representing dietary supplementation with 1.0% l-arginine–HCl or 1.7% l-alanine (isonitrogenous control) between days 22 and 114 of gestation. Blood samples were obtained from the ear vein on days 22, 40, 70 and 90 of gestation. On days 40, 70 and 90 of gestation, concentrations of estradiol in plasma were higher (P?<?0.05) in arginine-supplemented than in control sows. Moreover, arginine supplementation increased (P?<?0.05) the concentrations of arginine, proline and ornithine in plasma, but concentrations of urea or progesterone in plasma did not differ between the two groups of sows. Compared with the control, arginine supplementation increased (P?<?0.05) the total number of piglets by 1.31 per litter, the number of live-born piglets by 1.10 per litter, the litter birth weight for all piglets by 1.36?kg, and the litter birth weight for live-born piglets by 1.70?kg. Furthermore, arginine supplementation enhanced (P?<?0.05) placental weight by 16.2%. The weaning-to-estrus interval of sows was not affected by arginine supplementation during gestation. These results indicate that dietary arginine supplementation beneficially enhances placental growth and the reproductive performance of sows.     

Lipid metabolism in pigs fed supplemental conjugated linoleic acid and/or dietary arginine

We proposed that the combination of conjugated linoleic acid (CLA) and arginine would decrease adiposity by depressing lipid synthesis in liver and adipose tissues of growing pigs. Pigs were allotted to treatments in a 2 × 2 factorial design with two lipids (CLA or canola oil) and two amino acids [l-arginine or l-alanine (isonitrogenous control)]; supplements were provided from 80 to 110 kg body weight (approximately 4 weeks). Treatment groups (n = 4) were: control (2.05% l-alanine plus 1% canola oil); CLA (2.05% l-alanine plus 1% CLA); arginine (1.0% l-arginine plus 1.0% canola oil); arginine plus CLA (1.0% arginine plus 1.0% CLA). Arginine increased backfat thickness (P = 0.07) in the absence or presence of CLA, and arginine supplementation increased subcutaneous and retroperitoneal adipocyte volume, especially in combination with dietary CLA (interaction P = 0.001). Arginine increased palmitate incorporation into total lipids by over 60% in liver (P = 0.07). Dietary CLA increased palmitate incorporation into lipids in longissimus muscle by over 100% (P = 0.01), and CLA increased longissimus muscle lipid by nearly 20%. CLA increased glucose oxidation to CO₂ by over 80% in retroperitoneal and subcutaneous adipose tissues (P = 0.04), and doubled palmitate oxidation to CO₂ in intestinal duodenal mucosal cells (P = 0.07). Arginine supplementation decreased muscle pH at 45 min postmortem (P = 0.001), indicating elevated early postmortem glycolysis, and CLA and arginine independently increased PGC-1α gene expression in longissimus muscle. CLA but not arginine depressed mTOR gene expression in intestinal duodenal mucosal cells. CLA decreased serum insulin by 50% (P = 0.02) but increased serum triacylglycerols by over 40%. CLA supplementation increased (P ≤ 0.01) total saturated fatty acids in liver and adipose tissue. In conclusion, neither CLA nor arginine depressed tissue lipid synthesis in growing/finishing pigs, and in fact dietary CLA promoted elevated intramuscular lipid and arginine increased carcass adiposity.     

Effects of dietary l-arginine or N-carbamylglutamate supplementation during late gestation of sows on the miR-15b/16, miR-221/222, VEGFA and eNOS expression in umbilical vein

Placental vascular formation and blood flow are crucial for fetal survival, growth and development, and arginine regulates vascular development and function. This study determined the effects of dietary arginine or N-carbamylglutamate (NCG) supplementation during late gestation of sows on the microRNAs, vascular endothelial growth factor A (VEGFA) and endothelial nitric oxide synthase (eNOS) expression in umbilical vein. Twenty-seven landrace?×?large white sows at day (d) 90 of gestation were assigned randomly to three groups and fed the following diets: a control diet and the control diet supplemented with 1.0% l-arginine or 0.10% NCG. Umbilical vein of fetuses with body weight around 2.0?kg (oversized), 1.5?kg (normal) and 0.6?kg (intrauterine growth restriction, IUGR) were obtained immediately after farrowing for miR-15b, miR-16, miR-221, miR-222, VEGFA and eNOS real-time PCR analysis. Compared with the control diets, dietary Arg or NCG supplementation enhanced the reproductive performance of sows, significantly increased (P?<?0.05) plasma arginine and decreased plasma VEGF and eNOS (P?<?0.05). The miR-15b expression in the umbilical vein was higher (P?<?0.05) in the NCG-supplemented group than in the control group. There was a trend in that the miR-222 expression in the umbilical vein of the oversized fetuses was higher (0.05?<?P?<?0.1) than in the normal and IUGR fetuses. The expression of eNOS in both Arg-supplemented and NCG-supplemented group were lower (P?<?0.05) than in the control group. The expression of VEGFA was higher (P?<?0.05) in the NCG-supplemented group than in the Arg-supplemented and the control group. Meanwhile, the expression of VEGFA of the oversized fetuses was higher (P?<?0.05) than the normal and IUGR fetuses. In conclusion, this study demonstrated that dietary Arg or NCG supplementation may affect microRNAs (miR-15b, miR-222) targeting VEGFA and eNOS gene expressions in umbilical vein, so as to regulate the function and volume of the umbilical vein, provide more nutrients and oxygen from the maternal to the fetus tissue for fetal development and survival, and enhance the reproductive performance of sows.     

Impacts of arginine nutrition on embryonic and fetal development in mammals

Embryonic loss and intrauterine growth restriction (IUGR) are significant problems in humans and other animals. Results from studies involving pigs and sheep have indicated that limited uterine capacity and placental insufficiency are major factors contributing to suboptimal reproduction in mammals. Our discovery of the unusual abundance of the arginine family of amino acids in porcine and ovine allantoic fluids during early gestation led to the novel hypothesis that arginine plays an important role in conceptus (embryo and extra-embryonic membranes) development. Arginine is metabolized to ornithine, proline, and nitric oxide, with each having important physiological functions. Nitric oxide is a vasodilator and angiogenic factor, whereas ornithine and proline are substrates for uterine and placental synthesis of polyamines that are key regulators of gene expression, protein synthesis, and angiogenesis. Additionally, arginine activates the mechanistic (mammalian) target of rapamycin cell signaling pathway to stimulate protein synthesis in the placenta, uterus, and fetus. Thus, dietary supplementation with 0.83 % l-arginine to gilts consuming 2 kg of a typical gestation diet between either days 14 and 28 or between days 30 and 114 of pregnancy increases the number of live-born piglets and litter birth weight. Similar results have been reported for gestating rats and ewes. In sheep, arginine also stimulates development of fetal brown adipose tissue. Furthermore, oral administration of arginine to women with IUGR has been reported to enhance fetal growth. Collectively, enhancement of uterine as well as placental growth and function through dietary arginine supplementation provides an effective solution to improving embryonic and fetal survival and growth.     

The production and secretion of cortisol by baboon neonates.

The metabolic clearance rate (MCR), transfer constants (p), production (PR) and secretion (SR) rates of cortisol (F) andrortisone (E) were determined by the continuous infusion of {1,2³H}F and {4-¹⁴C}E into 5 neonates delivered prior to the parturition by cesarean section (164–179 days; term = 184 days) and into 5 newborns delivered spontaneously per vagina at term (166 – 187 days). In spontaneously delivered animals, MCR-E (X ± SE, 34.3 ± 7.0 1/day/kg was greater (P < 0.001) than MCR-F (14.9 ± 1.5 1/day/kg), pF to E (59.7 ± 8.9%) exceeded (P < 0.001) pE to F (17.8 ± 3.0%) and the percentage of F bound to serum proteins other than albumin (57.5 ± 6.2) was greater (P < 0.001) than that of E (27.0 ± 10.3) Although the serum E level (25.6 ± 3.6 μg/100 ml) was similar to that of F (33.5 ± 8.0 μg/100 ml), the PR-E (6.4 ± 1.3 μ/min/kg) was greater (P < 0.001) than PR-F (3.3 ± 0.5 μ/min/kg). Approximately eighty-five percent of the E and 65% of the F produced orginated by secretion.In animals delivered by cesarean section, the serum F concentration (32.4 ± 6.7 μ/100ml), pE to F (13.4 ± 2.8%) pF to E (80.0 ± 12.2%) PR-E (4.5 ± 0.2 μ/min/kg) and SR-E (3.9 ± 0.3 μ/min/kg) were not different from values for spontaneously delivered animals. Serum E levels (35.9 ± 1.6 μ/100 ml) were higher but MCR-F (6.7 ± 0.6 1/day/kg) and MCR-E (18.2 ± 0.41/day/kg) lower in neonates delivered by cesarean section. Serum Cortisol binding capacity (μg F bound/100 ml) was greater (P < 0.025) in neonates delivered by cesarean section (23.6 ± 2.6) than in spontaneously delivered animals (14.4 ± 2.0). As a result of these changes in F and E dynamics, PR-F (1.4 ± 0.3 μ/min/kg) and SR-F (0.9 ± 0.2 μ/min/kg) in neonates delivered by cesarean section were lower (P< 0.01) than corresponding values in spontaneously delivered newborns.It is concluded that the greater F secretion in animals delivered spontaneously than those delivered by cesarean section probably results from increased fetal adrenal 3β-hydroxysteroid dehydrogenase-isomerase activity, which as previously reported, occurs in late gestation in this species.     

Effect of dietary arginine supplementation on reproductive performance of mice with porcine circovirus type 2 infection

The objective of this study was to investigate whether supplemental dietary arginine increases reproductive performance in mice infected with porcine circovirus type2 (PCV2). A total of 50KM female mice were allotted randomly to the arginine group (0.6% arginine?+?gestation diet) and control group (1.22% alanine?+?gestation diet). All the mice began to mate after 14?days of treatment with our prepared feed and challenged with PCV2 at the dose of 100 TCID₅₀ (50% tissue culture infection dose, TCID₅₀) after 7?days of pregnancy. Abortion rate, litter number, litter birth weight, the daily weight gain in the first 7?days and survival rate in the first 2?weeks of the neonates were calculated. The serum progesterone, estrogen, nitric oxide and superoxide dismutase (SOD) activity and total antioxidant capacity (T-AOC) on the 14th day of pregnancy were measured. Arginine supplementation decreased the abortion rate of pregnant mice and mortality of neonates caused by PCV2 infection. Further, litter number, litter birth weight and the daily weight gain of neonates increased in the arginine group compared to the control group. Arginine supplementation increased significantly the serum progesterone (P?<?0.01) and nitric oxide levels (P?<?0.05), but had little effect on the serum estrogen level. SOD activity and T-AOC in the arginine group were significantly higher (P?<?0.01) than the control group. In conclusion, arginine supplementation partially reversed the reproductive failure in mice caused by PCV2 infection.     

A role for membrane transport in modulation of intramuscular free glutamine turnover in streptozotocin diabetic rats

We wished to examine the effects of diabetes on muscle glutamine kinetics. Accordingly, female Wistar rats (200 g) were made diabetic by a single injection of streptozotocin (85 mg/kg) and studied 4 days later; control rats received saline. In diabetic rats, glutamine concentration of gastrocnemius muscle was 33% less than in control rats: 2.60 ± 0.06 μmol/g vs. 3.84 ± 0.13 μmol/g (P < 0.001). In gastrocnemius muscle, glutamine synthetase activity (V_max) was unaltered by diabetes (approx. 235 nmol/min per g) but glutaminase V_max increased from 146 ± 29 to 401 ± 94 nmol/min per g; substrate K_m values of neither enzyme were affected by diabetes. Net glutamine efflux (AZ concentration difference × blood flow) from hindlimbs of diabetic rats in vivo was greater than control values (?30.0 ± 3.2 vs. ?1.9 ± 2.6 nmol/min per g (P < 0.001) and hindlimb NH₃ uptake was concomitantly greater (about 27 nmol/min per g). The glutamine transport capacity (V_max) of the Na-dependent System N^m in perfused hindlimb muscle was 29% lower in diabetic rats than in controls (820 ± 50 vs. 1160 ± 80 nmol/min per g (P < 0.01)), but transporter K_m was the same in both groups (9.2 ± 0.5 nM). The difference between inward and net glutamine fluxes indicated that glutamine efflux in perfused hindlimbs was stimulated in diabetes at physiological perfusate glutamine (0.5 mM); ammonia (1 mM in perfusate) had little effect on net glutamine flux in control and diabetic muscles. In Intramuscular Na⁺ was 26% greater in diabetic (13.2 μmol/g) than control muscle, but muscle K⁺ (100 μmol/g) was similar. The accelerated rate of glutamine release from skeletal muscle and the lower muscle free glutamine concentration observed in diabetes may result from a combination of; (i), a diminished Na⁺ electrochemical gradient (i.e., the net driving force for glutamine accrual in muscle falls); (ii), a faster turnover of glutamine in muscle and (iii), an increased V_max/K_m for sarcolemmal glutamine efflux.     

Dietary supplementation with l-arginine between days 14 and 25 of gestation enhances embryonic development and survival in gilts

Embryonic loss is a major problem in mammals, but there are few effective ways to prevent it. Using a porcine model, we determined effects of dietary l-arginine supplementation between days 14 and 25 of gestation on embryonic growth and survival. Gilts were checked daily for estrus with boars in the morning and bred at onset of the second estrus and 12 h later (the time of breeding = day 0 of gestation). Between days 14 and 25 of gestation, 15 gilts/treatment were housed individually and fed twice daily 1 kg of a corn- and soybean meal-based diet supplemented with 0.0, 0.4, or 0.8 % l-arginine. All diets were made isonitrogenous by addition of l-alanine. On day 25 of gestation, gilts were hysterectomized to obtain conceptuses. Compared with controls, dietary supplementation with 0.4 or 0.8 % l-arginine increased (P ≤ 0.05) arginine concentrations in maternal plasma, total volume of amniotic fluid; total amounts of arginine in allantoic and amniotic fluids; total amounts of fructose and most amino acids in amniotic fluid; placental growth; and the number of viable fetuses per litter by 2. The numbers of total fetuses, fetal weight, corpora lutea, volume of allantoic fluid, maternal circulating levels of progesterone and estrogen, or total amounts of hormones in allantoic fluid did not differ among the three treatment groups. Reproductive performance of gilts did not differ between the 0.4 and 0.8 % l-arginine groups. Thus, dietary supplementation with 0.4 or 0.8 % l-arginine between days 14 and 25 of gestation enhances embryonic/fetal survival in swine.     

Effect of oral progesterone and caffeine at the end of gestation on farrowing duration and piglet growth and survival

The profitability of pig production is constrained by high incidences of peri-parturient and pre-weaning piglet mortality. Supplementing sows with either progesterone or caffeine during the last week of gestation can reduce stillbirths and improve piglet performance. However, the consequences of combining these two substances has not been investigated. The aim of the current study was to determine the effect of oral supplementation of sows with progesterone (regumate) and caffeine at the end of gestation on the timing and progression of farrowing, as well as piglet survival and growth to weaning. From days 111 to 113 of gestation, 20 Large White pregnant sows (parity 3.0±0.45) received 5 ml of Regumate Porcine (0.4 w/v oral solution; MSD Animal Health) daily on top of their morning ration. Sows were stratified according to parity and predicted farrowing date, and allocated at random to receive a diet supplemented with either 0 g caffeine/kg diet (CONT) or 2.4 g of caffeine/kg diet (CAFF) from day 113 of gestation until parturition (n=10 sows/treatment). Treatment did not affect total litter size; however, CONT sows gave birth to more live and fewer dead piglets compared with CAFF sows; 14.5±0.73 v. 11.7±1.03 and 0.7±0.20 v. 3.2±0.77; P<0.05). Mean, minimum and maximum piglet birthweight were unaffected by treatment. Compared with the control, caffeine increased the proportion of piglets with a birthweight <1 kg (0.16±0.05 v. 0.05±0.02; P=0.072) and decreased the proportion of live born piglets surviving to day 5 postpartum (0.77±0.06 v. 0.90±0.02; P<0.05) and to weaning (0.74±0.06 v. 0.90±0.02; P<0.05). Overall, the current data provided the first evidence that caffeine supplementation of sows receiving progesterone to prevent premature farrowing impaired piglet survival during, and shortly after parturition. This negative outcome may be linked to extended farrowing durations and an increase in the proportion of very light piglets at birth. These data provide compelling, albeit preliminary, evidence that caffeine and progesterone should not be used together at the end of gestation.     

Effects of Chromium Propionate on Egg Production,Egg Quality,Plasma Biochemical Parameters,and Egg Chromium Deposition in Late-Phase Laying Hens

This study was conducted to investigate the effects of chromium propionate on egg production, egg quality, plasma biochemical parameters and egg chromium deposition in late-phase laying hens. Four hundred thirty-two 60-weeks old laying hens were divided into four groups of 108 birds per group according to egg production. The dietary treatments consisted of the basal diet adding with 0, 200, 400, and 600 μg/kg chromium as chromium propionate. All laying hens were given feed and water ad libitum for 8 weeks. The addition of 400 μg/kg Cr as chromium propionate increased egg production (P?<?0.01) during the later 4 weeks, but decreased albumen height, yolk color score, and Haugh unit of eggs. Six hundred micrograms per kilogram Cr as chromium propionate supplementation improved shell thickness (P?<?0.05). 200 μg/kg Cr as chromium propionate supplementation decreased the uric acid concentration by 31 % (P?<?0.05). However, supplemental Cr did not affect the egg chromium deposition of hens (P?>?0.05). These data indicated that feeding of late-phase laying hens with chromium propionate could improve egg production, increase eggshell thickness, but do not result in abnormal levels of chromium deposition in eggs.     

Pharmacological PPARα Activation Markedly Alters Plasma Turnover of the Amino Acids Glycine,Serine and Arginine in the Rat

The current study extends previously reported PPARα agonist WY 14,643 (30 µmol/kg/day for 4 weeks) effects on circulating amino acid concentrations in rats fed a 48% saturated fat diet. Steady-state tracer experiments were used to examine in vivo kinetic mechanisms underlying altered plasma serine, glycine and arginine levels. Urinary urea and creatinine excretion were measured to assess whole-body amino acid catabolism. WY 14,643 treated animals demonstrated reduced efficiency to convert food consumed to body weight gain while liver weight was increased compared to controls. WY 14,643 raised total amino acid concentration (38%), largely explained by glycine, serine and threonine increases. ³H-glycine, ¹⁴C-serine and ¹⁴C-arginine tracer studies revealed elevated rates of appearance (R_a) for glycine (45.5±5.8 versus 17.4±2.7 µmol/kg/min) and serine (21.0±1.4 versus 12.0±1.0) in WY 14,643 versus control. Arginine was substantially decreased (−62%) in plasma with estimated R_a reduced from 3.1±0.3 to 1.2±0.2 µmol/kg/min in control versus WY 14,643. Nitrogen excretion over 24 hours was unaltered. Hepatic arginase activity was substantially decreased by WY 14,643 treatment. In conclusion, PPARα agonism potently alters metabolism of several specific amino acids in the rat. The changes in circulating levels of serine, glycine and arginine reflected altered fluxes into the plasma rather than changes in clearance or catabolism. This suggests that PPARα has an important role in modulating serine, glycine and arginine de novo synthesis.     

Characterization of arginine transport in Helicobacter pylori

Background. The amino acid L‐arginine is an essential requirement for growth of Helicobacter pylori. Several physiological roles of this amino acid have been identified in the bacterium, but very little is known about the transport of L‐arginine and of other amino acids into H. pylori. Methods. Radioactive tracer techniques using L‐(U‐¹⁴C) arginine and the centrifugation through oil method were employed to measure the kinetic parameters, temperature dependence, substrate specificity, and effects of analogues and inhibitors on L‐arginine transport. Results. The transport of arginine at millimolar concentrations was saturable with a K_m of 2.4 ± 0.3 mM and V_max of 1.3 ± 0.2 pmole min^?1 (µl cell water)^?1 or 31 ± 3 nmole per minute (mg protein)^?1 at 20°C, depended on temperature between 4 and 40°C, and was susceptible to inhibitors. These characteristics suggested the presence of one or more arginine carriers. The substrate specificity of the transport system was studied by measuring the effects of L‐arginine analogues and amino acids on the rates of transport of L‐arginine. The absence of inhibition in competition experiments with L‐lysine and L‐ornithine indicated that the transport system was not of the Lysine‐Arginine‐Ornithine or Arginine‐Ornithine types. The presence of different monovalent cations did not affect the transport rates. Several properties of L‐arginine transport were elucidated by investigating the effects of potential inhibitors. Conclusions. The results provided evidence that the transport of L‐arginine into H. pylori cells was carrier‐mediated transport with the driving force supplied by the chemical gradient of the amino acid.     

Supplementing sow diets with palm oil during late gestation and lactation: effects on milk production,sow hormonal profiles and growth and development of her offspring

The supplementing of sow diets with lipids during pregnancy and lactation has been shown to reduce sow condition loss and improve piglet performance. The aim of this study was to determine the effects of supplemental palm oil (PO) on sow performance, plasma metabolites and hormones, milk profiles and pre-weaning piglet development. A commercial sow ration (C) or an experimental diet supplemented with 10% extra energy in the form of PO, were provided from day 90 of gestation until weaning (24 to 28 days postpartum) in two groups of eight multiparous sows. Gestation length of PO sows increased by 1 day (P<0.05). Maternal BW changes were similar throughout the trial, but loss of backfat during lactation was reduced in PO animals (C: −3.6±0.8 mm; PO: −0.1±0.8 mm; P<0.01). Milk fat was increased by PO supplementation (C day 3: 8.0±0.3% fat; PO day 3: 9.1±0.3% fat; C day 7: 7.8±0.5% fat; PO day 7: 9.9±0.5% fat; P<0.05) and hence milk energy yield of PO sows was also elevated (P<0.05). The proportion of saturated fatty acids was greater in colostrum from PO sows (C: 29.19±0.31 g/100 g of fat; PO: 30.77±0.36 g/100 g of fat; P<0.01). Blood samples taken on 105 days of gestation, within 24 h of farrowing, day 7 of lactation and at weaning (28±3 days post-farrowing) showed there were no differences in plasma concentrations of triacylglycerol, non-esterified fatty acids, insulin or IGF-1 throughout the trial. However, circulating plasma concentrations of both glucose and leptin were elevated during lactation in PO sows (P<0.05 and P<0.005, respectively) and thyroxine was greater at weaning in PO sows (P<0.05). Piglet weight and body composition were similar at birth, as were piglet growth rates throughout the pre-weaning period. A period of 7 days after birth, C piglets contained more body fat, as indicated by their lower fat-free mass per kg (C: 66.4±0.8 arbitrary units/kg; PO: 69.7±0.8 arbitrary unit/kg; P<0.01), but by day 14 of life this situation was reversed (C: 65.8±0.6 arbitrary units/kg; PO: 63.6±0.6 arbitrary units/kg; P<0.05). Following weaning, PO sows exhibited an increased ratio of male to female offspring at their subsequent farrowing (C: 1.0±0.3; PO: 2.2±0.2; P<0.05). We conclude that supplementation of sow diets with PO during late gestation and lactation appears to increase sow milk fat content and hence energy supply to piglets. Furthermore, elevated glucose concentrations in the sow during lactation may be suggestive of impaired glucose homoeostasis.     

A saturation transfer phosphorus nuclear magnetic resonance study of arginine phosphokinase in the muscle of a marine mollusc

The forward and reverse fluxes of arginine phosphokinase were measured in vitro preparations of the phasic adductor muscle of the scallop Argopecten irradians concentricus using saturation transfer ³¹P-NMR techniques. The respective fluxes were 4.72 ± 1.46 and 6.98 ± 1.58 μmol/s per g wet weight. The forward-to-reverse flux ratio was near unity, indicating that the arginine phosphokinase reaction is near equilibrium under resting conditions. ³¹P-NMR spectra showed no evidence of ADP in scallop muscles. Using an experimentally determined apparent equilibrium constant for arginine phosphokinase, the free ADP level was estimated to be 51 nmol/g wet wt. It appears that at least 90% of the ADP pool is bound in this muscle.     

Arginine supplementation and exposure time affects polyamine and glucose metabolism in primary liver cells isolated from Atlantic salmon

Arginine has been demonstrated to enhance glucose and lipid oxidation in mammals through activation of polyamine turnover. We aimed to investigate how arginine affects energy utilization through polyamine metabolism and whether this effect is time dependent. Primary liver cells were isolated from Atlantic salmon (2.2 kg body weight) fed diets containing 25.5 (low arginine, LA) or 36.1 (high arginine, HA) g arginine/kg dry matter for 12 weeks, to investigate the effect of long-term arginine supplementation. The cells were cultured for 24 h in L-15 medium to which either alpha-difluoromethylornithine (DFMO) or N ¹,N ¹¹-diethylnorspermine (DENSPM) was added. Analysis of the medium by nuclear magnetic resonance revealed significant differences between the two dietary groups as well as between cells exposed to DFMO and DENSPM, with decreased glucose, fumarate and lactate concentrations in media of the HA cells. Liver cells from fish fed the HA diet had higher spermidine/spermine-N1-acetyltransferase protein abundance and lower adenosine triphosphate concentration as compared to the LA-fed fish, while gene expression was not affected by either diet or treatment. Primary liver cells isolated from salmon fed a commercial diet and cultured in L-15 media with or without arginine supplementation (1.82 or 3.63 mM) for 48 h, representing short-term effect of arginine supplementation, showed differential expression of genes for apoptosis and polyamine synthesis due to arginine supplementation or inhibition by DFMO. Overall, arginine concentration and exposure time affected energy metabolism and gene regulation more than inhibition or activation of key enzymes of polyamine metabolism, suggesting a polyamine-independent influence of arginine on cellular energy metabolism and survival.     

Elemental Analysis of Whole and Protein Separated Blood Serum of Patients with Systemic Lupus Erythematosus and Sjögren’s Syndrome

Data on the effects of selenium supplementation on clinical signs and metabolic profiles in women at risk for intrauterine growth restriction (IUGR) are scarce. This study was designed to assess the effects of selenium supplementation on clinical signs and metabolic status in pregnant women at risk for IUGR. This randomized double-blind placebo-controlled clinical trial was performed among 60 women at risk for IUGR according to abnormal uterine artery Doppler waveform. Participants were randomly assigned to intake either 100 μg selenium supplements as tablet (n = 30) or placebo (n = 30) for 10 weeks between 17 and 27 weeks of gestation. After 10 weeks of selenium administration, a higher percentage of women in the selenium group had pulsatility index (PI) of <1.45) (P = 0.002) than of those in the placebo group. In addition, changes in plasma levels of total antioxidant capacity (TAC) (P < 0.001), glutathione (GSH) (P = 0.008), and high-sensitivity C-reactive protein (hs-CRP) (P = 0.004) in the selenium group were significant compared with the placebo group. Additionally, selenium supplementation significantly decreased serum insulin (P = 0.02), homeostasis model of assessment-estimated insulin resistance (HOMA-IR) (P = 0.02), and homeostatic model assessment for B-cell function (HOMA-B) (P = 0.02) and significantly increased quantitative insulin sensitivity check index (QUICKI) (P = 0.04) and HDL-C levels (P = 0.02) compared with the placebo. We did not find any significant effect of selenium administration on malondialdehyde (MDA), nitric oxide (NO), fasting plasma glucose (FPG), and other lipid profiles. Overall, selenium supplementation in pregnant women at risk for IUGR resulted in improved PI, TAC, GSH, hs-CRP, and markers of insulin metabolism and HDL-C levels, but it did not affect MDA, NO, FPG, and other lipid profiles.Clinical trial registration number http://www.irct.ir: IRCT201601045623N64.     

The Influences of Chromium Supplementation on Glycemic Control,Markers of Cardio-Metabolic Risk,and Oxidative Stress in Infertile Polycystic ovary Syndrome Women Candidate for In vitro Fertilization: a Randomized,Double-Blind,Placebo-Controlled Trial

This study was carried out to investigate the effects of chromium intake on glycemic control, markers of cardio-metabolic risk, and oxidative stress in infertile polycystic ovary syndrome (PCOS) women candidate for in vitro fertilization (IVF). This randomized double-blind, placebo-controlled trial was done among 40 subjects with infertile PCOS candidate for IVF, aged 18–40 years old. Individuals were randomly allocated into two groups to take either 200 μg/day of chromium (n?=?20) or placebo (n?=?20) for 8 weeks. Biochemical parameters were assessed at baseline and at end-of-trial. Compared with the placebo, taking chromium supplements led to significant reductions in fasting plasma glucose (??2.3?±?5.7 vs. +?0.9?±?3.1 mg/dL, P?=?0.03), insulin levels (??1.4?±?2.1 vs. +?0.4?±?1.7 μIU/mL, P?=?0.004), homeostatic model of assessment for insulin resistance (??0.3?±?0.5 vs. +?0.1?±?0.4, P?=?0.005), and a significant increase in quantitative insulin sensitivity check index (+?0.004?±?0.008 vs. ??0.001?±?0.008, P?=?0.03). In addition, chromium supplementation significantly decreased serum triglycerides (??19.2?±?33.8 vs. +?8.3?±?21.7 mg/dL, P?=?0.004), VLDL- (??3.8?±?6.8 vs. +?1.7?±?4.3 mg/dL, P?=?0.004) and total cholesterol concentrations (??15.3?±?26.2 vs. ??0.6?±?15.9 mg/dL, P?=?0.03) compared with the placebo. Additionally, taking chromium supplements was associated with a significant increase in plasma total antioxidant capacity (+?153.9?±?46.1 vs. ??7.8?±?43.9 mmol/L, P?<?0.001) and a significant reduction in malondialdehyde values (?0.3?±?0.3 vs. +?0.1?±?0.2 μmol/L, P?=?0.001) compared with the placebo. Overall, our study supported that chromium administration for 8 weeks to infertile PCOS women candidate for IVF had beneficial impacts on glycemic control, few variables of cardio-metabolic risk, and oxidative stress.     

Effect of supplementation on the performance of grazing Belgian Blue double-muscled heifers

Six experiments were conducted to investigate the effect of a feed supplement on the performance of grazing Belgian Blue double-muscled (BBDM) heifers with an initial weight and age of 195 ± 43 kg and 190 ± 52 days. Treatments included were: Exp. 1: supplementation with beet pulp (BP): 2 kg/day per head v. ad libitum intake; Exp. 2: supplementation ad libitum with BP v. a mixture of BP and soybean meal (SBM; BP/SBM ratio of 80/20; FW (fresh weight) basis); Exp. 3: supplementation with 4 kg/day per head of a mixture of BP/SBM (80/20; FW basis) v. BP/formaldehyde-treated SBM (BP/FSBM); Exp. 4: supplementation with 4 kg/day per head of a mixture with a similar protein content (125 g DVE per kg dry matter (DM)), consisting of 80/20 BP/SBM v. 92/8 BP/FSBM; Exp. 5: supplementation with 3 kg/day per head of a mixture of BP/SBM (80/20; FW basis) v. BP/DDGS (dried distillers grains and solubles; 70/30, FW basis); and Exp. 6: supplementation with 3 kg/day per head of 80/20 BP/SBM v. maize silage (MS) and SBM, on the basis of a similar protein concentration in the DM as the 80/20 BP/SBM supplement, and fed at a similar amount of DM as in the BP/SBM group. Supplementing BP ad libitum did not affect daily gain (0.54 v. 0.48 kg) and partial feed conversion (3.62 kg on average) compared with 2 kg/day. Supplying SBM besides BP increased growth rate compared with BP (0.87 v. 0.62 kg/day; P < 0.001), but partial feed conversion was similar. Supplying FSBM did not affect growth rate and partial feed conversion (P > 0.10), but blood urea levels were reduced by FSBM (P < 0.05). DDGS tended to increase growth rate (0.77 v. 0.59 kg/day; P < 0.10) compared with BP/SBM, without effect on partial feed conversion. Replacing BP by MS did not affect daily gain, but partial feed conversion tended to be higher (3.21 v. 3.60 kg/kg body weight (BW) gain; P = 0.062). Increasing the supplement (80/20 BP/SBM) level from 3 to 4 kg daily, corresponding to 1.02% and 1.18% of the mean BW, respectively, resulted in a tendency (P = 0.121) for an increased growth rate. Grazing BBDM heifers of <1 year of age necessitate extra protein besides an energy supplement to improve their performance. DDGS can replace SBM and BP can be replaced by MS.     

Solubilization of active (H+ + K+)-ATPase from gastric membrane

(H⁺ + K⁺)-ATPase-enriched membranes were prepared from hog gastric mucosa by sucrose gradient centrifugation. These membranes contained Mg²⁺-ATPase and p-nitrophenylphosphatase activities (68 ± 9 μmol P_i and 2.9 ± 0.6 μmol p-nitrophenol/mg protein per h) which were insensitive to ouabain and markedly stimulated by 20 mM KCl (respectively, 2.2- and 14.8-fold). Furthermore, the membranes autophosphorylated in the absence of K⁺ (up to 0.69 ± 0.09 nmol P_i incorporated/mg protein) and dephosphorylated by 85% in the presence of this ion. Membrane proteins were extracted by 1–2% (w/v) n-octylglucoside into a soluble form, i.e., which did not sediment in a 100 000 × g × 1 h centrifugation. This soluble form precipitated upon further dilution in detergent-free buffer. Extracted ATPase represented 32% (soluble form) and 68% (precipitated) of native enzyme and it displayed the same characteristic properties in terms of K⁺-stimulated ATPase and p-nitrophenylphosphatase activities and K⁺-sensitive phosphorylation: Mg²⁺-ATPase (μmol P_i/mg protein per h) 32 ± 9 (basal) and 86 ± 20 (K⁺-stimulated); Mg²⁺-p-nitrophenylphosphatase (μmol p-nitrophenol/mg protein per h) 2.6 ± 0.5 (basal) and 22.2 ± 3.2 (K⁺-stimulated); Mg²⁺-phosphorylation (nmol P_i/mg protein) 0.214 ± 0.041 (basal) and 0.057 ± 0.004 (in the presence of K⁺). In glycerol gradient centrifugation, extracted enzyme equilibrated as a single peak corresponding to an apparent 390 000 molecular weight. These findings provide the first evidence for the solubilization of (H⁺ + K⁺)-ATPase in a still active structure.     

Synchronization of oestrus in gilts with altrenogest: effects on ovulation rate and foetal survival

Previous studies have shown that use of altrenogest resulted in a high rate of fertility and increased litter size compared with controls under conditions of practical pig production. The present study was designed to evaluate whether ovulation rate and/or foetal survival were increased by altrenogest using crossbred gilts derived from one herd (n = 227) and introduced in the same piggery over 12 months. Each gilt was allocated to a treated group (n = 103) receiving an individual daily dose of 20 mg of altrenogest for 18 days in its feed or a control group (n = 124) after puberty had been diagnosed, (197 ± 1 day; mean ± SEM). They were inseminated (double AI) at the second induced or natural oestrus. Pregnancy was diagnosed by ultrasonography at Days 22 and 42 post-insemination in the absence of return to oestrus. Pregnant gilts were slaughtered at 48 ± 3 days of pregnancy following the second examination. The number of living and dead foetuses were recorded before uterine contents (foetuses and placentae) were weighed and the number of corpora lutea (CL) per ovary counted.Precise synchronization of oestrus was observed after the end of the progestogen administration, with 93% of the gilts in oestrus by Days 5 to 7. For the controls, the interval from first to second oestrus ranged from 17 to 25 days in 93% of the control gilts. The pregnancy rate was 89.3% for treated gilts and 77.4% for controls (P < 0.05). The ovulation rate was increased by the treatment (15.4 ± 0.3 vs 14.6 ± 0.3; mean ± SEM, P < 0.02). Although the altrenogest group had more foetuses (11.1 vs 10.6), this difference was not significant (P > 0.14). The percent of foetal survival was similar in both groups (64.9%; P > 0.27). The foetal and placental weights differed only between dams and increased with stage of gestation. The increase in litter size through feeding altrenogest was associated with an increased ovulation rate.