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Delbert M Gatlin - One of the best experts on this subject based on the ideXlab platform.
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evaluation of Sulfur Amino Acid and zinc supplements to soybean meal based diets for hybrid striped bass
Aquaculture, 2010Co-Authors: Christine L Savolainen, Delbert M GatlinAbstract:Abstract Hybrid striped bass ( Morone chrysops × M. saxatilis ) aquaculture is a major commercial enterprise in the United States and internationally. Efforts to decrease diet costs and limit dependence on fishmeal have led to the development of plant-based diets as alternative aquafeeds. Due to limiting concentrations of some Amino Acids such as methionine and cystine, in plant meals such as soybean meal, supplementation of plant-based diets with methionine or other Sulfur Amino Acid compounds may be required. High levels of soybean meal also may reduce the bioavailability of minerals such as zinc due to the inhibitory effects of phytate. Therefore, the current study was conducted to evaluate different Sulfur Amino Acid and zinc supplements in soybean-meal-based diets with hybrid striped bass for possible refinement of diets and reduction of production costs. In the first feeding trial, a basal soybean-meal-based diet (56% soybean meal and 15% fishmeal) marginally deficient in total Sulfur Amino Acids (TSAA) (1.10% methionine and cystine) was supplemented with either l -methionine, methionine hydroxyl analog (MHA) calcium salt or Mintrex® (liquid MHA with chelated zinc) and fed to triplicate groups of juvenile hybrid striped bass for 10 weeks. The different methionine supplements provided similar weight gain, feed efficiency ratio (FER) and protein efficiency ratio (PER) values that tended to be greater than observed in fish fed the basal diet. Mintrex® supplementation provided much higher plasma zinc concentrations compared to fish fed the other methionine supplements. In additional feeding trials, a soybean-meal-based control diet containing l -methionine to satisfy the requirement for TSAA was supplemented with varying concentrations of zinc sulfate or Mintrex®, each to provide 5, 10, and 20 μg Zn/kg diet, and fed to juvenile hybrid striped bass. The different zinc concentrations did not affect zinc integration into the scale or bone of hybrid striped bass after 8 weeks of feeding. Zinc from zinc sulfate in comparison to Mintrex® was absorbed slightly but significantly better based on postprandial serum zinc concentrations of fish fed the two products at the same dietary zinc concentration; however, these absorption differences did not affect long-term zinc deposition in the scale and bone.
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dietary sufficiency of Sulfur Amino Acid compounds influences plasma ascorbic Acid concentrations and liver peroxidation of juvenile hybrid striped bass morone chrysops m saxatilis
Aquaculture, 2009Co-Authors: Gary S Burr, Jonathan B Goff, Qin Wen, Shivananda H Murthy, Delbert M GatlinAbstract:Abstract The influence of Sulfur Amino Acid (SAA) sufficiency in aquafeeds on tissue antioxidant status including liver ascorbic Acid and lipid peroxidation has not been investigated with any fish to date. In this study, a basal diet consisting of lyophilized fish muscle and a crystalline Amino Acid premix without supplemental SAAs and containing 0.51% total SAAs (methionine + cystine) served as the negative control to which three graded levels of dl -methionine ( dl -met) or dl -2-hydroxy-4-methylthiobutanoic Acid (MHA) were added. Quadruplicate groups of juvenile hybrid striped bass were fed each diet in a recirculating system for 6 weeks. Increases in dl -met or MHA in the diets linearly increased weight gain, survival, feed efficiency, protein efficiency ratio, protein conversion efficiency, whole-body protein and some Amino Acids in whole-body tissues. Because high inclusion levels of MHA (4.5–5.4 g/kg) increased intraperitoneal fat and also decreased whole-body protein and Amino Acids, protein conversion efficiency was used to determine relative bioavailability of MHA, which was 74.6% as effective as dl -met on an equal-weight basis. Fish fed 5.4 g MHA/kg diet had significantly higher ascorbic Acid concentration in circulation than fish fed the basal diet or diets including 1.5, 3.0 g dl -met/kg or 4.5 g MHA/kg. The thiobarbituric Acid reactive substances (TBARS) in liver also were negatively related to sufficiency of dietary SAA compounds. The present study is the first to provide evidence that methionine deficiency in aquafeeds may reduce/exhaust reservoirs of antioxidants such as ascorbic Acid in fish tissue, which may result in irreversible oxidative stress and potentially bilateral cataracts as well as aggravate growth retardation, depressed feed efficiency and mortality.
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evaluation of different Sulfur Amino Acid compounds in the diet of red drum sciaenops ocellatus and sparing value of cystine for methionine
Aquaculture, 2004Co-Authors: Jonathan B Goff, Delbert M GatlinAbstract:Abstract Relatively large substitution of plant protein feedstuffs for animal feedstuffs in the diet of red drum will likely require supplementation of methionine to meet this species' metabolic requirement. Therefore, two feeding trials were conducted to determine the value of different Sulfur compounds in diets for red drum, and to re-evaluate the cystine replacement value for methionine. The basal diet in both trials was formulated to contain 35% crude protein from red drum muscle and crystalline Amino Acids. The feeding trials compared growth characteristics of red drum fed different Sulfur Amino Acid (SAA) compounds including l -methionine (control), dl -methionine, crystalline methionine hydroxy analog (MHA), N -acetyl- dl -methionine, or Alimet™, a liquid MHA, supplemented to the basal diet on an equal-Sulfur basis to meet the minimum SAA requirement of red drum. Various ratios of cystine to methionine (40/60, 45/55, and 50/50) also were added to the basal diet to re-evaluate the potential sparing effect of cystine for methionine. All diets were fed to triplicate groups of fingerling red drum in 110-l aquaria connected as a brackish (7‰) water recirculating system for 8 and 7 weeks in trials 1 and 2, respectively. Fish fed the basal diet had significantly ( P l -methionine and the other SAA compounds. Results from this study indicate red drum were able to use the various SAA compounds equally as effective as l -methionine to meet their SAA requirement. Cystine also was able to spare approximately 50% of the dietary methionine requirement of red drum.
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evaluation of different Sulfur compounds in the diet of juvenile sunshine bass morone chrysops m saxatilis
Comparative Biochemistry and Physiology Part A: Physiology, 1995Co-Authors: C N Keembiyehetty, Delbert M GatlinAbstract:Abstract A semipurified basal diet with 35% crude protein, 0.38% methionine and 0.13% cystine was supplemented with different Sulfur compounds to evaluate their efficacy in satisfying the total Sulfur Amino Acid requirement of sunshine bass (Morone chrysops ♀ × M. saxatilis ♂). A control diet was supplemented with l -methionine to meet the total Sulfur Amino Acid requirement of sunshine bass, and test diets were supplemented with either dl -methionine, dl -methionine hydroxy analog (MHA), N-acetyl- dl -methionine, taurine or glutathione on an equal-Sulfur basis with the control diet. Fingerlings of sunshine bass (mean initial wt ± SD = 11.3 ± 0.1 g) were reared in a brackish water recirculating system, and triplicate groups of fish were fed the different diets twice daily. After 8 weeks of feeding, the greatest weight gain as well as best feed and protein utilization values was observed among fish fed diets containing l -methionine, dl -methionine and N-acetyl- dl -methionine. Glutathione and MHA were about 75% as effective in promoting growth compared with l -methionine, while taurine was totally ineffective. Fish fed glutathione had a significantly greater hepatosomatic index (HSI; liver weight × 100/body weight) and lower intraperitoneal fat ratio (IPF ratio; intraperitoneal fat weight × 100/body weight). Plasma methionine level was highest in fish fed dl -methionine. Highest whole-body protein levels were found in fish fed l -methionine, N-acetyl- dl -methionine, and dl -methionine, while the lowest level was in fish fed glutathione. Based on these results, dl -methionine and N-acetyl- dl -methionine were most effective relative to l -methionine in satisfying the Sulfur Amino Acid requirement of sunshine bass.
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total Sulfur Amino Acid requirement of juvenile hybrid striped bass morone chrysops m saxatilis
Aquaculture, 1993Co-Authors: C N Keembiyehetty, Delbert M GatlinAbstract:Abstract Two separate feeding trials were conducted to determine the total Sulfur Amino Acid requirement of hybrid striped bass. Semipurified diets containing 35% crude protein from fish muscle and crystalline Amino Acids were supplemented with graded levels of methionine. Each diet was fed to juvenile fish in triplicate aquaria receiving freshwater for 8 weeks. Fish fed the basal diet which contained 0.38% methionine and 0.13% cystine experienced complete mortality within 1 week. Prior to death, some fish fed inadequate methionine were observed to have bilateral cataracts. Weight gain and feed efficiency of fish were significantly ( P
Amany K Elshorbagy - One of the best experts on this subject based on the ideXlab platform.
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Sulfur Amino Acid restriction energy metabolism and obesity a study protocol of an 8 week randomized controlled dietary intervention with whole foods and Amino Acid supplements
Journal of Translational Medicine, 2021Co-Authors: Emma Stolt, Thomas Olsen, Bente Ovrebo, Amany K Elshorbagy, Viktor Kožich, Marleen M J Van Greevenbroek, Magne Thoresen, Helga RefsumAbstract:Dietary Sulfur Amino Acid (SAA) restriction is an established animal model for increasing lifespan and improving metabolic health. Data from human studies are limited. In the study outlined in this protocol, we will evaluate if dietary SAA restriction can reduce body weight and improve resting energy expenditure (REE) and parameters related to metabolic health. Men and women (calculated sample size = 60), aged 18–45 years, with body mass index of 27–35 kg/m2 will be included in a double-blind 8-week dietary intervention study. The participants will be randomized in a 1:1 manner to a diet with either low or high SAA. Both groups will receive an equal base diet consisting of low-SAA plant-based whole foods and an Amino Acid supplement free of SAA. Contrasting SAA contents will be achieved using capsules with or without methionine and cysteine (SAAhigh, total diet SAA ~ 50–60 mg/kg body weight/day; SAAlow, total diet SAA ~ 15–25 mg/kg body weight/day). The primary outcome is body weight change. Data and material collection will also include body composition (dual X-ray absorptiometry), resting energy expenditure (whole-room indirect calorimetry) and samples of blood, urine, feces and adipose tissue at baseline, at 4 weeks and at study completion. Measures will be taken to promote and monitor diet adherence. Data will be analyzed using linear mixed model regression to account for the repeated measures design and within-subject correlation. The strength of this study is the randomized double-blind design. A limitation is the restrictive nature of the diet which may lead to poor compliance. If this study reveals a beneficial effect of the SAAlow diet on body composition and metabolic health, it opens up for new strategies for prevention and treatment of overweight, obesity and its associated disorders. Trial registration ClinicalTrials.gov: NCT04701346, Registration date: January 8th, 2021
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body composition in gene knockouts of Sulfur Amino Acid metabolizing enzymes
Mammalian Genome, 2014Co-Authors: Amany K ElshorbagyAbstract:Plasma concentrations of several Amino Acids are elevated in human obesity and insulin resistance, but there is no conclusive evidence on whether the Amino Acid alterations are causal. Dietary restriction of the essential SAA methionine (MR) in rats produces a hypermetabolic phenotype, with an integrated set of transcriptional changes in lipid enzymes in liver and adipose tissue. MR also induces an array of changes in methionine metabolites, including elevated plasma homocysteine and decreased cystathionine, cysteine, glutathione, and taurine. Several knockouts of enzymes acting downstream of methionine recapitulate the phenotypic results of MR, suggesting that the MR phenotype may be driven by changes distal to methionine. Here we review the changes in SAA and body composition in seven relevant knockout mouse models. All seven models feature decreased body weight, which in five of these have been further explored and shown to result from predominantly decreased fat mass. Common to several models is increased energy expenditure, enhanced insulin sensitivity, and protection against dietary obesity, as occurs in MR. A decrease in plasma total cysteine concentrations is also seen in most models. The lean phenotype could often be reversed by dietary supplementation of cysteine or choline, but not taurine, betaine or a H2S donor. Importantly, the plasma concentrations of both cysteine and choline are positively associated with fat mass in large populations studies, while taurine, betaine, and H2S are not. Collectively, the emerging data from dietary and knockout models are in harmony with human epidemiologic data, suggesting that the availability of key nutrients in the SAA pathway regulates fat storage pathways.
Paul B. Pencharz - One of the best experts on this subject based on the ideXlab platform.
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total Sulfur Amino Acid requirements are not altered in children with chronic renal insufficiency but minimum methionine needs are increased
Journal of Nutrition, 2017Co-Authors: Rajavel Elango, Ronald O. Ball, Mahroukh Rafii, Mohammad A Humayun, Justine M Turner, Veronika Langos, Paul B. PencharzAbstract:Background: The total Sulfur Amino Acid (TSAA) and minimum Met requirements have been previously determined in healthy children. TSAA metabolism is altered in kidney disease. Whether TSAA requirements are altered in children with chronic renal insufficiency (CRI) is unknown.Objective: We sought to determine the TSAA (Met in the absence of Cys) requirements and minimum Met (in the presence of excess Cys) requirements in children with CRI.Methods: Five children (4 boys, 1 girl) aged 10 ± 2.6 y with CRI were randomly assigned to receive graded intakes of Met (0, 5, 10, 15, 25, and 35 mg · kg-1 · d-1) with no Cys in the diet. Four of the children (3 boys, 1 girl) were then randomly assigned to receive graded dietary intakes of Met (0, 2.5, 5, 7.5, 10, and 15 mg · kg-1 · d-1) with 21 mg · kg-1 · d-1 Cys. The mean TSAA and minimum Met requirements were determined by measuring the oxidation of l-[1-13C]Phe to 13CO2 (F13CO2). A 2-phase linear-regression crossover analysis of the F13CO2 data identified a breakpoint at minimal F13CO2 Urine samples collected from all study days and from previous studies of healthy children were measured for Sulfur metabolites.Results: The mean and population-safe (upper 95% CI) intakes of TSAA and minimum Met in children with CRI were determined to be 12.6 and 15.9 mg · kg-1 · d-1 and 7.3 and 10.9 mg · kg-1 · d-1, respectively. In healthy school-aged children the mean and upper 95% CI intakes of TSAA and minimum Met were determined to be 12.9 and 17.2 mg · kg-1 · d-1 and 5.8 and 7.3 mg · kg-1 · d-1, respectively. A comparison of the minimum Met requirements between healthy children and children with CRI indicated significant (P < 0.05) differences.Conclusion: These results suggest that children with CRI have a similar mean and population-safe TSAA to that of healthy children, suggesting adequate Cys synthesis via transSulfuration, but higher minimum Met requirement, suggesting reduced remethylation rates.
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Sulfur Amino Acid metabolism and requirements
Nutrition Reviews, 2012Co-Authors: Glenda Courtneymartin, Ronald O. Ball, Paul B. PencharzAbstract:The Sulfur Amino Acids (SAA) are methionine and cysteine. Methionine is indispensable.1–5 It donates its Sulfur atom to cysteine during the process of trans-Sulfuration, making cysteine a dispensable Amino Acid.6 The carbon skeleton of cysteine, however, is donated by serine.6 Methionine is metabolized via three major metabolic pathways: transmethylation, remethylation, and trans-Sulfuration. It serves as the major methyl group donor in vivo,7,8 while cysteine is the rate-limiting substrate for the synthesis of the antioxidant glutathione (GSH).9–11 Both Amino Acids are important for protein synthesis. The total Sulfur Amino Acid (TSAA) requirement, when fulfilled by the provision of methionine, can be significantly reduced only by adding cysteine to the diet. This phenomenon has been firmly established in animals12–15 and in humans16–18; it is consistent across the lifespan, having been observed in neonates,5–20 children,21 and adults.17,18 In the present issue of this journal, F. Jahoor examines the role the availability of Sulfur Amino Acids plays in severe childhood undernutrition.22 The present editorial complements that work by providing an overview of SAA metabolism and requirements. ### Methionine In healthy adults, the metabolism of methionine is regulated toward anabolism23 in the fed state, and methionine flux is increased relative to that observed in the fasted state. Feeding results in decreased methionine release from protein breakdown and increased transmethylation, trans-Sulfuration, and remethylation. In the fasted state, methionine utilization for protein synthesis is increased relative to transmethylation, resulting in the conservation of methionine when SAA availability is low. When SAAs are absent from the diet of healthy adults,17 methionine is used preferentially for protein synthesis relative to transmethylation, confirming previous findings that methionine is conserved via protein synthesis when SAA …
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total Sulfur Amino Acid requirement and metabolism in parenterally fed postsurgical human neonates
The American Journal of Clinical Nutrition, 2008Co-Authors: Glenda Courtneymartin, Ronald O. Ball, Karen P Chapman, Aideen M Moore, Jae H Kim, Paul B. PencharzAbstract:Background: Except for tyrosine, the Amino Acid requirements of human neonates receiving parenteral nutrition (PN) have not been experimentally derived. Objectives: The objectives were to determine the total Sulfur Amino Acid (TSAA) requirement (methionine in the absence of cysteine) of postsurgical, PN-fed human neonates by using the indicator Amino Acid oxidation (IAAO) technique with L-[ 1 - 13 C]phenylalanine as the indicator. Design: Fifteen postsurgical neonates were randomly assigned to receive 1 of 18 methionine intakes ranging from 10 to 120 mg ·kg -1 ·d -1 , delivered in a customized, cysteine-free Amino Acid solution. Breath and urine samples were collected for the measurement of 13 CO 2 and Amino Acid enrichment. Blood samples were collected at baseline and after the test methionine infusion for the measurement of plasma methionine, homocysteine, cystathionine, and cysteine concentrations. Results: Breakpoint analysis determined the mean TSAA requirements to be 47.4 (95% CI: 38.7,56.1) and 49.0 (95% CI: 39.9, 58.0) mg ·kg -1 ·d -1 with the use of oxidation and F 13 CO 2 , respectively. Conclusions: This is the first study to report the TSAA requirement of postsurgical, PN-fed human neonates. The estimated methionine requirement expressed as a proportion of the methionine content of current commercial pediatric PN solutions was 90% (range: 48-90%) of that found in the lowest methionine-containing PN solution.
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the in vivo sparing of methionine by cysteine in Sulfur Amino Acid requirements in animal models and adult humans
Journal of Nutrition, 2006Co-Authors: Ronald O. Ball, Glenda Courtneymartin, Paul B. PencharzAbstract:Sulfur Amino Acid metabolism has been receiving increased attention because of the link to chronic diseases such as cardiovascular disease, Alzheimer's disease, and diabetes. In addition, the role of cysteine and optimal intakes for physiological substrates such as glutathione are currently of considerable interest in human health. Although the dietary indispensability of methionine is not in question, the ability of cysteine to substitute for a portion of its requirement has been the topic of much debate. Methionine is often the most limiting Amino Acid in the diets of the developing world's population because of its low concentration in cereal grains. Therefore, the ability of cysteine to substitute for methionine requirement is not just biologically interesting; it is also of considerable economic and social importance. The primary goal of this review is to discuss the available evidence on the effect of cysteine substitution for methionine to meet the total Sulfur Amino Acid requirement in adult humans, including an assessment of the methodological features of experiments with conflicting results. Assessment of the requirement experiments for Amino Acids with complex metabolism such as methionine and cysteine must begin with a careful definition of requirements and what substitution means. As a result of these definitions, a set of criteria for the intakes of methionine that will allow demonstration of the substitution effect have been developed. Some recent publications are assessed using these definitions and criteria, and a possible reason for the conflicting results in the literature is proposed. An approach to estimating tolerable upper intakes is also proposed. Research on in vivo Sulfur Amino Acid metabolism in humans is tremendously difficult, and therefore, we do not wish to be overly critical of the high-quality work of the ambitious and highly intelligent men and women who have conducted various studies. Our goal is to objectively review the data for the reader in a logical and comprehensive manner and propose methods that may avoid difficulties in future studies.
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total Sulfur Amino Acid requirement of healthy school age children as determined by indicator Amino Acid oxidation technique
The American Journal of Clinical Nutrition, 2006Co-Authors: Justine M Turner, Ronald O. Ball, Mahroukh Rafii, Rajavel Elango, Mohammad A Humayun, Veronika Langos, Paul B. PencharzAbstract:Background: Current total Sulfur Amino Acid (TSAA) requirements of children are based on a factorial estimate that involves several assumptions. Objective: The objective was to determine the TSAA requirement (methionine alone) of healthy school-age children by measuring the appearance of 13 CO 2 (F 13 CO 2 ) in breath after the oxidation of L-[1- 13 C]phenylalanine in response to graded methionine intakes. Design: Six healthy school-age children randomly received each of 6 methionine intakes (0, 5, 10, 15, 25, and 35 mg ·kg -1 ·d -1 ) along with an Amino Acid mixture to give a. final protein intake of 1.5 g · kg -1 ·d -1 and an energy intake of 1.7 x resting energy expenditure. The diet was devoid of cysteine. The mean TSAA requirement was determined by applying a biphase linear regression crossover analysis on F 13 CO 2 data, which identified a breakpoint at minimal F 13 CO 2 in response to graded methionine intakes. Results: The mean and population-safe (upper 95% CI) intakes of TSAA (as methionine) were determined to be 12.9 and 17.2 mg· kg -1 ·d -1 , respectively. Conclusions: The current study suggests that children of this age group have a mean TSAA requirement similar to that of adults (12.6 mg kg -1 ·d -1 ). Therefore, it is valid to use a factorial approach, which assumes that maintenance requirements in childhood are similar to adult requirements, to estimate TSAA requirements in school-age children.
Helga Refsum - One of the best experts on this subject based on the ideXlab platform.
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Sulfur Amino Acid restriction energy metabolism and obesity a study protocol of an 8 week randomized controlled dietary intervention with whole foods and Amino Acid supplements
Journal of Translational Medicine, 2021Co-Authors: Emma Stolt, Thomas Olsen, Bente Ovrebo, Amany K Elshorbagy, Viktor Kožich, Marleen M J Van Greevenbroek, Magne Thoresen, Helga RefsumAbstract:Dietary Sulfur Amino Acid (SAA) restriction is an established animal model for increasing lifespan and improving metabolic health. Data from human studies are limited. In the study outlined in this protocol, we will evaluate if dietary SAA restriction can reduce body weight and improve resting energy expenditure (REE) and parameters related to metabolic health. Men and women (calculated sample size = 60), aged 18–45 years, with body mass index of 27–35 kg/m2 will be included in a double-blind 8-week dietary intervention study. The participants will be randomized in a 1:1 manner to a diet with either low or high SAA. Both groups will receive an equal base diet consisting of low-SAA plant-based whole foods and an Amino Acid supplement free of SAA. Contrasting SAA contents will be achieved using capsules with or without methionine and cysteine (SAAhigh, total diet SAA ~ 50–60 mg/kg body weight/day; SAAlow, total diet SAA ~ 15–25 mg/kg body weight/day). The primary outcome is body weight change. Data and material collection will also include body composition (dual X-ray absorptiometry), resting energy expenditure (whole-room indirect calorimetry) and samples of blood, urine, feces and adipose tissue at baseline, at 4 weeks and at study completion. Measures will be taken to promote and monitor diet adherence. Data will be analyzed using linear mixed model regression to account for the repeated measures design and within-subject correlation. The strength of this study is the randomized double-blind design. A limitation is the restrictive nature of the diet which may lead to poor compliance. If this study reveals a beneficial effect of the SAAlow diet on body composition and metabolic health, it opens up for new strategies for prevention and treatment of overweight, obesity and its associated disorders. Trial registration ClinicalTrials.gov: NCT04701346, Registration date: January 8th, 2021
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combining dietary Sulfur Amino Acid restriction with polyunsaturated fatty Acid intake in humans a randomized controlled pilot trial
Nutrients, 2018Co-Authors: Thomas Olsen, Bente Ovrebo, C A P Turner, Nasser E Bastani, Helga Refsum, Kathrine J VinknesAbstract:Dietary and plasma total cysteine (tCys) have been associated with adiposity, possibly through interaction with stearoyl–CoA desaturase (SCD), which is an enzyme that is involved in fatty Acid and energy metabolism. We evaluated the effect of a dietary intervention with low cysteine and methionine and high polyunsaturated fatty Acids (PUFAs) on plasma and urinary Sulfur Amino Acids and SCD activity indices. Fourteen normal-weight healthy subjects were randomized to a seven-day diet low in cysteine and methionine and high in PUFAs (Cys/Metlow + PUFA), or high in saturated fatty Acids (SFA), cysteine, and methionine (Cys/Methigh + SFA). Compared with the Cys/Methigh + SFA group, plasma methionine and cystathionine decreased (p-values < 0.05), whereas cystine tended to increase (p = 0.06) in the Cys/Metlow + PUFA group. Plasma total cysteine (tCys) was not significantly different between the groups. Urinary cysteine and taurine decreased in the Cys/Metlow + PUFA group compared with the Cys/Methigh + SFA group (p-values < 0.05). Plasma SCD-activity indices were not different between the groups, but the change in cystine correlated with the SCD-16 index in the Cys/Metlow + PUFA group. A diet low in methionine and cysteine decreased plasma methionine and urinary cysteine and taurine. Plasma tCys was unchanged, suggesting that compensatory mechanisms are activated during methionine and cysteine restriction to maintain plasma tCys.
Dean P Jones - One of the best experts on this subject based on the ideXlab platform.
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hepatic oxidative stress in fructose induced fatty liver is not caused by Sulfur Amino Acid insufficiency
Nutrients, 2011Co-Authors: Sachin Kunde, James R Roede, Miriam B Vos, Michael Orr, Youngja Park, Thomas R Ziegler, Dean P JonesAbstract:Fructose-sweetened liquid consumption is associated with fatty liver and oxidative stress. In rodent models of fructose-mediated fatty liver, protein consumption is decreased. Additionally, decreased Sulfur Amino Acid intake is known to cause oxidative stress. Studies were designed to test whether oxidative stress in fructose-sweetened liquid-induced fatty liver is caused by decreased ad libitum solid food intake with associated inadequate Sulfur Amino Acid intake. C57BL6 mice were grouped as: control (ad libitum water), fructose (ad libitum 30% fructose-sweetened liquid), glucose (ad libitum 30% glucose-sweetened water) and pair-fed (ad libitum water and Sulfur Amino Acid intake same as the fructose group). Hepatic and plasma thiol-disulfide antioxidant status were analyzed after five weeks. Fructose- and glucose-fed mice developed fatty liver. The mitochondrial antioxidant protein, thioredoxin-2, displayed decreased abundance in the liver of fructose and glucose-fed mice compared to controls. Glutathione/glutathione disulfide redox potential (EhGSSG) and abundance of the cytoplasmic antioxidant protein, peroxiredoxin-2, were similar among groups. We conclude that both fructose and glucose-sweetened liquid consumption results in fatty liver and upregulated thioredoxin-2 expression, consistent with mitochondrial oxidative stress; however, inadequate Sulfur Amino Acid intake was not the cause of this oxidative stress.
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a Sulfur Amino Acid free meal increases plasma lipids in humans
Journal of Nutrition, 2011Co-Authors: Youngja Park, Thomas R Ziegler, Frederick H Strobel, Nana Gletsumiller, Carolyn Jonas Accardi, Kichun Lee, Dean P JonesAbstract:The content of Sulfur Amino Acid (SAA) in a meal affects postprandial plasma cysteine concentrations and the redox potential of cysteine/cystine. Because such changes can affect enzyme, transporter, and receptor activities, meal content of SAA could have unrecognized effects on metabolism during the postprandial period. This pilot study used proton NMR (1H-NMR) spectroscopy of human plasma to test the hypothesis that dietary SAA content changes macronutrient metabolism. Healthy participants (18–36 y, 5 males and 3 females) were equilibrated for 3 d to adequate SAA, fed chemically defined meals without SAA for 5 d (depletion), and then fed isoenergetic, isonitrogenous meals containing 56 mg·kg−1·d−1 SAA for 4.5 d (repletion). On the first and last day of consuming the chemically defined meals, a morning meal containing 60% of the daily food intake was given and plasma samples were collected over an 8-h postprandial time course for characterization of metabolic changes by 1H-NMR spectroscopy. SAA-free food increased peak intensity in the plasma 1H-NMR spectra in the postprandial period. Orthogonal signal correction/partial least squares-discriminant analysis showed changes in signals associated with lipids, some Amino Acids, and lactate, with notable increases in plasma lipid signals (TG, unsaturated lipid, cholesterol). Conventional lipid analyses confirmed higher plasma TG and showed an increase in plasma concentration of the lipoprotein lipase inhibitor, apoC-III. The results show that plasma 1H-NMR spectra can provide useful macronutrient profiling following a meal challenge protocol and that a single meal with imbalanced SAA content alters postprandial lipid metabolism.
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dietary Sulfur Amino Acid effects on fasting plasma cysteine cystine redox potential in humans
Nutrition, 2011Co-Authors: Dean P Jones, Youngja Park, Nana Gletsumiller, Carolyn Jonas Accardi, Yongliang Liang, Thomas R ZieglerAbstract:Abstract Objective Oxidation of plasma cysteine/cystine (Cys/CySS) redox potential (EhCySS) has been associated with risk factors for cardiovascular disease in humans. Cys and CySS are derived from dietary Sulfur Amino Acids (SAA), but the specific effects of SAA depletion and repletion on Cys/CySS redox indices are unknown. The present study examined the effect of dietary SAA intake level on free Cys, free CySS, and EhCySS in human plasma under fasting conditions. Methods Healthy individuals aged 18–36 y (n = 13) were equilibrated to foods providing the RDA for SAA and then fed chemically defined diets without SAA (0 mg·kg–1·d–1; n = 13) followed by SAA at levels approximating the mean (56 mg·kg–1·d–1; n = 8) or 99th percentile (117 mg·kg–1·d–1; n = 5) intake levels of Americans. Fasting plasma samples were collected daily during 4-d study periods and analyzed for free Cys, free CySS, and the EhCySS. Results The SAA-free diet significantly (P Conclusions These results show that free Cys and Cys/CySS redox potential (EhCySS) in fasting plasma are affected by dietary SAA intake level in humans. Significant changes occur slowly over 4 d with insufficient SAA intake, but rapidly (after 1 d) with repletion.
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oxidation of plasma cysteine cystine and gsh gssg redox potentials by acetAminophen and Sulfur Amino Acid insufficiency in humans
Journal of Pharmacology and Experimental Therapeutics, 2010Co-Authors: Yanci O Mannery, Youngja Park, Thomas R Ziegler, Dean P JonesAbstract:Variations in plasma Sulfur Amino Acid (SAA) pools are associated with disease risks, but little information is available about the factors affecting plasma SAA pools. Drug metabolism by glutathione (GSH) and sulfate conjugation can, in principle, represent a quantitatively important burden on SAA supply. The present study was designed to determine whether therapeutic doses of acetAminophen (APAP) alter SAA metabolism in healthy human adults. A double-blind, crossover design incorporating four treatment periods with diets providing 100% of the recommended dietary allowance (RDA) for SAA without or with APAP (15 mg/kg) and 0% RDA for SAA without or with APAP, in randomized order. After a 3-day equilibration period, chemically defined diets with 100 or 0% RDA for SAA were given for 2 complete days. On day 3, APAP or placebo was given in two successive doses (6-h interval), and timed plasma samples were collected. With SAA intake at 100% RDA, APAP administration oxidized the plasma cysteine/cystine redox potential (EhCySS) but not the plasma GSH/GSSG redox potential (EhGSSG). The extent of oxidation caused by APAP was similar to that seen with 0% SAA and no APAP. However, APAP administration with 0% SAA did not cause further oxidation beyond APAP or 0% SAA alone. In contrast, an oxidation of the plasma EhGSSG was apparent for SAA insufficiency only with APAP. The results suggest a need to evaluate possible effects of APAP in association with SAA insufficiency as a contributing factor in disease risk.
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acetAminophen elimination half life in humans is unaffected by short term consumption of Sulfur Amino Acid free diet
Journal of Pharmacology and Experimental Therapeutics, 2010Co-Authors: Yanci O Mannery, Youngja Park, Thomas R Ziegler, Dean P JonesAbstract:Sulfation and glutathione (GSH) conjugation are important pathways for elimination of acetAminophen (APAP). Previous studies in rodents show that limitation of dietary Sulfur Amino Acids (SAAs) reduces biosynthesis of 3′-phosphoadenosine-5′-phosphosulfate, the precursor for sulfation, and GSH, the precursor for the mercapturatic Acid pathway. The amount of SAA needed for the metabolism of two doses of APAP is equivalent to 62% of the recommended dietary allowance (RDA) for SAA in humans. A decrease in the activity of these metabolic pathways could lead to decreased elimination of the reactive metabolite of APAP and possibly affect risk of APAP use. To determine whether intake of a SAA-deficient diet alters APAP metabolism, a pilot clinical study with a double-blind, cross-over design was performed. Subjects received the RDA for SAA for 3 days for equilibration. After admission to the clinical research unit, subjects were given a chemically defined diet with 100 or 0% of the RDA for SAA for 2 days. On day 3, two doses of APAP (15 mg/kg) or placebo were given successively within a 6-h interval. Plasma samples were collected at baseline and hourly for 12 h, and two 6-h urine aliquots were collected during this time course. The data show that SAA limitation 1) did not change the pattern of APAP metabolites in plasma or urine and 2) did not alter APAP pharmacokinetics. Thus, the results show that 2 days of diet completely devoid of SAA have no effect on APAP metabolism or disposition in healthy humans.
