Met Levels Research Articles

Effects of supplemental d-methionine in comparison to l-methionine on nitrogen retention, gut morphology, antioxidant status, and mRNA abundance of amino acid transporters in weanling pigs.

An N-balance experiment was conducted to test the hypothesis that d-Methionine (d-Met) has the same bioavailability and efficacy as l-Methionine (l-Met) when fed to weanling pigs. A Met-deficient basal diet containing 0.24% standardized ileal digestible (SID) Met was formulated. Six additional diets were formulated by adding 0.036%, 0.072%, or 0.108% d-Met or l-Met to the basal diet, and these diets, therefore, contained 77%, 87%, or 97% of the requirement for SID Met. Fifty-six barrows (10.53 ± 1.17 kg) were housed in metabolism crates and allotted to the seven diets with eight replicate pigs per diet. Feces and urine were collected quantitatively with 7-d adaptation and 5-d collection periods. Blood and tissue samples from pigs fed the basal diet and pigs fed diets containing 0.108% supplemental Met were collected on the last day. Results indicated that N retention (%) linearly increased (P < 0.01) as supplemental d-Met or l-Met increased in diets. Based on N retention (%) as a response, the linear slope-ratio regression estimated the bioavailability of d-Met relative to l-Met to be 101% (95% confidence interval: 57%-146%). The villus height and crypt depth in the jejunum were not affected by the Met level or Met source. Total antioxidant capacity or thiobarbituric acid reactive substance concentrations in plasma or tissue samples from pigs fed the control diet or diets containing 0.108% supplemental d-Met or l-Met were not different. Abundance of mRNA for some AA transporters analyzed in intestinal mucosa of pigs also did not differ. Therefore, it is concluded that d-Met and l-Met are equally bioavailable for weanling pigs.

Does Participation In An Exercise Program Increase Physical Activity On Non-Exercise Days?

Even though increased physical activity is well correlated with improvement in comorbidities among older adults, most older adults do not meet the recommended guidelines for physical activity. One of the ways that healthcare professionals have tried to increase physical activity is by implementing exercise programs using interactive exergames. Although these types of exercise programs have been shown to increase physical activity among older adults, research is lacking on the effects of exercise programs on non-program days. PURPOSE: To examine differences in the physical activity levels of older adults participating in a facility-based program, on intervention vs. non-intervention days. METHODS: Older veterans (N = 30, 87% male, 68.0 ± 6.7 years) were randomized to either a physical activity intervention (Wii Fit video games) or a control cognitive activity (Brain-Fitness computer games). Both groups participated in the facility-based program for 45-minute sessions, 3 days a week for 8 weeks. Actigraph data were collected for one week prior to starting the sessions and at four weeks. RESULTS: Among all participants who completed the study (N = 26), there was significant (p ≤ 0.05) improvement on days of facility-based participation versus off-days in average active Kcal expended (534.29 ± 303.18 vs. 456.26 ± 274.36), MET level (1.38 ± 0.13 vs. 1.33 ± 0.12), and step count (5848.93 ± 3757.53 vs. 4723.93 ± 3181.64) regardless of intervention assignment. Compared to the baseline, there was also significant improvement regardless of intervention assignment in participant step count on intervention days (4715.80 ± 2745.20 vs. 5848.93 ± 3757.53, p ≤ 0.05) but this improvement was not seen on the off-days. Additionally, regardless of intervention assignment there was a significant reduction in the total time spent per day in sedentary bouts on intervention days compared to off-days (217.32 ± 100.85 vs. 244.46 ± 103.70, p ≤ 0.05). CONCLUSIONS: This pilot study indicates that structured facility-based programs increase physical activity in older adults on intervention days but that additional research is needed to develop programs that lead to improved physical activity outside of facility-based interventions. Supported by SCVAHCN Network research grant program by the Department of Veterans Affairs

Abstract 1387: MET inhibition radiosensitizes KRAS-mutant rectal cancer

Abstract Rectal carcinoma, representing about a third of all newly diagnosed colorectal cancers, is one of the most common malignant tumors. The standard of care for locally advanced rectal cancer (LARC), consisting of neoadjuvant chemo/radiotherapy prior to surgical resection, is poorly effective, leading to complete tumor regression only in 10-30% of the cases. Approximately 40% of LARC harbor activating KRAS mutations, which have been extensively associated with primary resistance to targeted EGFR therapy and with radioresistance as well. Previous work showed that the MET receptor tyrosine kinase supports radioresistance and can be inhibited to radiosensitize tumor cell subpopulations retaining stem-like properties. Here, we show that LARC often express high levels of MET and can be successfully radiosensitized by MET inhibition. This was assessed in rectal stem-like cells isolated from human tumors (rectospheres), and transplanted in the mouse to regenerate tumors that faithfully reproduce the phenotype, the genotype and the therapeutic response of the original tumor. Mechanistically, we found that radioresistant KRAS-mutant rectospheres display significantly higher basal levels of RAD51, a master regulator of DNA homologous recombination repair, and increased RAD51 recruitment to irradiation-induced DNA double-strand breaks, as compared with KRAS-wild type rectospheres. Importantly, we showed that MET pharmacological inhibition by small-molecule kinase inhibitors, combined with radiotherapy, impairs RAD51 expression and function. This leads to DNA damage accumulation and results in effective radiosensitization of K-RAS-mutant rectal stem-like cells in vitro and in vivo, and significant inhibition of experimental tumors. Therefore, preclinical evidence is provided that MET can be exploited as a therapeutic target to radiosensitize KRAS-mutant rectal cancer at stem-like cell level. Citation Format: Antonio D'Ambrosio, Federica Verginelli, Francesca Orzan, Raffaella Albano, Elena Casanova, Paolo Luraghi, Francesca De Bacco, Andrea Bertotti, Livio Trusolino, Rebecca Senetta, Anna Sapino, Elena Del Mastro, Marco Gatti, Paolo M. Comoglio, Carla Boccaccio. MET inhibition radiosensitizes KRAS-mutant rectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1387.

Paternal exposure to excessive methionine altered behavior and neurochemical activities in zebrafish offspring.

An increase in plasma L-methionine (Met) levels, even if transitory, can cause important toxicological alterations in the affected individuals. Met is essential in the regulation of epigenetic mechanisms and its influence on the subsequent generation has been investigated. However, few studies have explored the influence of a temporary increase in Met levels in parents on their offspring. This study evaluated the behavioral and neurochemical effects of parental exposure to high Met concentration (3mM) in zebrafish offspring. Adult zebrafish were exposed to Met for 7days, maintained for additional 7days in tanks that contained only water, and then used for breeding. The offspring obtained from these fish (F1) were tested in this study. During the early stages of offspring development, morphology, heart rate, survival, locomotion, and anxiety-like behavior were assessed. When these animals reached the adult stage, locomotion, anxiety, aggression, social interaction, memory, oxidative stress, and levels of amino acids and neurotransmitters were analyzed. F1 larvae Met group presented an increase in the distance and mean speed when compared to the control group. F1 adult Met group showed decreased anxiety-like behavior and locomotion. An increase in reactive oxygen species was also observed in the F1 adult Met group whereas lipid peroxidation and antioxidant enzymes did not change when compared to the control group. Dopamine, serotonin, glutamate, and glutathione levels were increased in the F1 adult Met group. Taken together, our data show that even a transient increase in Met in parents can cause behavioral and neurochemical changes in the offspring, promoting transgenerational effects.

Effects of rumen-protected methionine supplementation on the performance of high production dairy cows in the tropics

Increasing methionine availability in dairy cow diets during the first third of lactation may enhance their performance and health. The aim of this study was to determine the effect of supplementing rumen-protected methionine (Smartamine® M, SM) in a lactation diet with protein and energy levels calculated according to the literature. Seventy-six multiparous Holstein cows (39.1 ± 6.8 kg of milk/d and 65 ± 28 DIM) were assigned to 1 of 2 dietary treatments (38/treatment) according to a randomized complete block design with a 2-wk (covariate) and 10-wk experimental period. Treatments were a basal diet (CON; 3.77 Lys:1Met); and CON + 23 g SM (2.97 Lys:1 Met). Individual milk samples were taken every 2 weeks to determine milk composition. Blood was collected from 24 cows on d+30 d to measure plasma AA levels. Body weight and body condition score (BCS) were measured at the beginning and the end of the experiment. The SM diet promoted higher milk yield (41.7 vs. 40.1 kg/d; P = 0.03). Energy-corrected milk yield (41.0 vs. 38.0 kg/d), milk protein yield (1.30 vs. 1.18 kg/d), milk protein (3.14% vs. 2.97%) and casein (2.39% vs. 2.28%) were also different (P < 0.01) as well as milk fat yield (1.42 vs. 1.29 kg/d; P = 0.02). A trend (P = 0.06) for higher milk fat % (3.41% vs. 3.21%) was observed. Both diets resulted in similar body weight, but CON-fed cows tended (P = 0.08) to have higher BCS. Higher plasma methionine levels were determined with SM compared with CON (29.6 vs. 18.4 μM; P < 0.01), but lysine and histidine were not different. Dietary supplementation of RPM improved productive performance by increasing milk yield and milk components yields, suggesting better dietary AA utilization when Met levels are adjusted in Lys-adequate lactation diets.

Effect of replacement different methionine levels and sources with betaine on blood metabolites, breast muscle morphology and immune response in heat-stressed broiler chickens

This study was performed to evaluate the effect of replacement different methionine (Met) levels and sources (DL or L) with betaine on blood metabolites, breast muscle morphology and immune response in heat-stressed broiler chickens. A total of 1200 unsexed day-old Ross-308 chicks were raised under the same condition in the first 10 days and then reared under normal or subnormal (32 °C) ambient temperatures for the 11 to 42 days of age. The experiment was designed as a split-plot factorial arrangement with 2 (temperatures) × 2 (Met sources) × 3 (Met levels) × 2 (betaine amounts). Met level in the basal diet was 30% lower than recommendation (Low-Met) and was increased to recommendation (Rec-Met) or 30% more than it (High-Met) by supplemental DL- or L-Met. Betaine was or was not substituted at the rate of 30% of the supplemental DL- or L-Met. From 11 to 24 d of age, broilers fed high-met diets showed better FCR than those received Low- and Rec-Met diet. High-Met diet under heat stress (HS) showed highest plasma uric acid and homocysteine concentration than two other diets, under normal or HS condition. Replacing 30% of the supplemental Met with betaine showed lower plasma homocysteine concentration compared to non-supplemented betaine diets. Birds fed Low- and Rec-Met diets under normal condition showed a significant decrease in heterophil/lymphocyte ratio compared to their counterparts under HS. Birds fed L-Met supplemented diet showed a greater myofibers diameter than birds fed DL-Met diet. In general, High-Met diet decreased heterophil/lymphocyte ratio and FCR of broilers. A total of 30% of dietary supplemental Met can be replaced by betaine. Highlights Heat stress increase methionine requirements of broiler chickens. L-methionine increases breast yield in compare with DL-methionine. Betaine in animal feed can be replaced by methionine without adverse effect on broiler chickens.

Effects of replacement different levels and sources of methionine with betaine on jejunal morphology, duodenal mitochondrial respiration, and lipid peroxidation in heat-stressed broiler chickens

This study aimed to investigate the effects of replacement different levels and sources of methionine (Met) with betaine on jejunal morphology, duodenal mitochondrial respiration, and lipid peroxidation in heat-stressed broiler chickens. A total of 1,200 one-day-old Ross 308 broilers were randomly assigned to two similar poultry houses. The experiment was designed as a 2 (ambient temperatures) × 2 (Met sources) × 3 (Met levels) × 2 (betaine amounts) split-plot factorial arrangement. Basal diets (Low-Met) were formulated with DL-or L-Met to meet Ross 308 nutrient recommendations except for Met which was 30% lower than the recommendation. Met level in basal diets was increased to the recommendation and/or 30% more than recommendation (High-Met) by supplemental DL-or L-Met. Betaine was or was not partially substituted at a 30% equivalent level of supplemental DL- or L-Met. HS was induced by increasing ambient temperature to 32 °C for 6 h daily in one house from 10 to 42 d. The highest feed conversion ratio (FCR) was observed in Low-Met diets. Low-L-Met diets showed greatest FCR than Low-DL-Met diets groups. Breast muscle malondialdehyde (MDA) concentration was decreased by increasing dietary Met level under HS. Duodenal MDA concentration and complex (Cox) III activity was lower and higher in L-Met diets than DL-Met diets, respectively. Cox II activity was increased in High-Met diets, and also was improved by betaine replacement. Villus height (VH) and Villus surface (VS) was increased in L-Met diets compared to DL-Met diets. Generally, L-Met was more effective than DL-Met in jejunal morphology, reducing duodenal MDA, and increasing Cox III activity. Betaine had the potential to be a partial replacement for Met. HIGHLIGHTS L-Met was more efficient than DL-Met in duodenal malondialdehyde concentration and complex III activity. Heat stress reduced the growth performance of broilers through its negative effects on intestinal development and duodenal activity of respiratory chain complexes. Betaine could have a protective effect on mitochondrial function in the tissues of broiler chickens.

1H NMR-based metabolomics approach for exploring the effect of astaxanthin supplementation on plasma metabolites after high-intensity physical exercise

Purpose: In this study, proton nuclear magnetic resonance (1H NMR) spectroscopy was used to evaluate the effect of astaxanthin (ASTA) supplementation on changes in human plasma elicited by high-intensity exercise. Methods: Sixteen adult males were randomly divided into 2 groups (n = 8 per group), namely the control group C (placebo for 28 d, 4 weeks) and experimental group M (supplement medium dose ASTA: 12 mg/d for 28 d, 4 weeks). At 08:00 on the 29th day, fasting blood sampling was carried out on all the participants, and the samples were tested in the laboratory for the first time. Later, the participants performed acute exercise on a pedal-powered bicycle with full strength for 30 s × 3/3 min intervals (loading a weight of 0.075 kg/kg). Blood sampling was then respectively performed immediately, 1 h after the acute exercise, and 1 d after the acute exercise. Results: (1) The metabolites of the subjects of the two groups were found to be diverse at different time points, and 34 types of metabolites were screened from the two groups. (2) The metabolites with differences between the two groups 1 h after exercise were β-hydroxybutyrate, creatine, and glycerol. The levels of β-hydroxybutyric acid and glycerol in group M were significantly lower than those in group C, while the level of creatine was significantly higher. Compared with the resting state 1 h after exercise, the metabolites in common between the two groups were leucine (Leu), valine (Val), and citric acid (CA), and their levels were significantly decreased. (3) During the period between 1 h and 1 d after exercise, the different metabolites between the two groups were methionine (Met) and glycerol. The glycerol levels of group M were significantly lower than those of group C, while the levels of Met were significantly higher. The co-metabolites of the subjects in groups C and M 1 d after exercise were creatine, glucose, and glycerol, the levels of which were all significantly increased. Conclusions: (1) One hour after exercise, the consumption of creatine, amino acids, fatty acids, and CA was found to be obvious, and ASTA intake was conducive to their recovery. (2) After high-intensity exercise, changes occurred in the body's energy metabolism that involved the metabolism of glucose, lipids, and proteins, and basic recovery was found 1 d after exercise. The findings of this study suggest that ASTA intake can accelerate metabolic recovery induced by physical exercise.

Effects of cardiac rehabilitation on cardiac autonomic functions in ankylosing spondylitis patients: A randomized controlled study

Aim: Ankylosing spondylitis (AS) is a systemic chronic inflammatory disease that has various adverse effects on cardiac autonomicfunctions. On the other hand, there is no data regarding the effects of cardiac rehabilitation on cardiac autonomic functions in ASpatients. In this study, we aimed to investigate the effects of cardiac rehabilitation on cardiac autonomic nervous system parametersin patients with AS.Materials and Methods: This study was designed as a prospective randomized controlled trial. The study was carried out in December2015 - August 2016. 34 patients who fulfilled the modified New York criteria were enrolled in the study. Patients were randomlyassigned into case and control groups each consisting of 17 patients. The cardiac rehabilitation program was applied to the casegroup for eight weeks. Patient evaluation with clinical assessment, echocardiography, and exercise stress testing was performedbefore and after treatment.Results: A total of 34 patients made the final study population (37.35± 5.22 years, 55.9% male). There were no significant differencesregarding the baseline characteristics between case and control groups. Patients in the case group had better MET levels, exercisetime, resting heart rate, and chronotropic reserve than the control patients following cardiac rehabilitation.Conclusion: Our results indicate that significant improvement in cardiac autonomic functions can be obtained in AS patients whenthe cardiac rehabilitation program is combined with the medical treatment.

Integration of MsrB1 and MsrB2 in the Redox Network during the Development of Orthodox and Recalcitrant Acer Seeds.

Two related tree species, Norway maple (Acer platanoides L.) and sycamore (Acer pseudoplatanus L.), produce desiccation-tolerant (orthodox) and desiccation-sensitive (recalcitrant) seeds, respectively. We compared the seeds of these two species to characterize the developmentally driven changes in the levels of peptide-bound methionine sulfoxide (MetO) and the abundance of methionine sulfoxide reductases (Msrs) B1 and B2, with respect to the cellular redox environment. Protein oxidation at the Met level was dynamic only in Norway maple seeds, and the reduced MsrB2 form was detected only in this species. Cell redox status, characterized by the levels of reduced and oxidized ascorbate, glutathione, and nicotinamide adenine dinucleotide (NAD)/phosphate (NADP), was clearly more reduced in the Norway maple seeds than in the sycamore seeds. Clear correlations between MetO levels, changes in water content and redox status were reported in orthodox Acer seeds. The abundance of Msrs was correlated in both species with redox determinants, mainly ascorbate and glutathione. Our data suggest that MsrB2 is associated with the acquisition of desiccation tolerance and that ascorbate might be involved in the redox pathway enabling the regeneration of Msr via intermediates that are not known yet.

PSVI-30 Requirements of the sulfur amino acids in growing Labrador Retrievers using the indicator amino acid oxidation technique

Abstract Over time, the need to update amino acid (AA) requirements for canines becomes increasingly important to ensure animals are healthy and free of nutritional disease. Each of the AA plays a crucial role in the metabolism and health of mammals. Of the essential AA, the total sulfur amino acids (TSAA), namely methionine (Met) and cysteine (Cys), are involved in metabolic functions such as protein metabolism, intestinal health, and urinary function. Additionally, Met can function as a precursor in the requirement of Cys. The purpose of this experiment was to use the indicator amino acid oxidation technique to determine amino acid requirements on growing Labrador Retrievers. A total of 12 dogs were subjected to 12 diets with varying levels of Met and Cys, ranging from deficient to excess. Diets were formulated to 1.6x NRC values for all indispensable amino acids. The control diet was fed for two days, followed by a day in which the test diet was fed, a tracer amino acid was supplied, and breath samples were collected. On test day, a priming dose of L-[1-13C]phenylalanine (Cambridge Isotope Laboratories, Inc.) based on the subject’s body weight was first supplied, followed by [1-13C]Phe doses every thirty minutes, spanning a four hour period. A respiration mask was placed on each subject every thirty minutes (Oxymax, Columbus Instruments), 13CO2 was collected, and enrichment was determined by isotope ratio mass spectrometry (IRMS). Results for IRMS were converted to atom percent excess (APE) and analyzed using a broken line model (JMP® Pro 15). Results showed that the Met and TSAA mean and population requirements were 0.78 ± 0.16 and 1.53 ± 0.21 g/1000kcal (mean ± 2SD), respectively. Knowledge gained from these studies is necessary as the petfood industry aims to deliver accurate diet formulations to the expansive canine population.

Effects of three methionine sources in diets on temporal B0AT1 and ASCT2 mRNA expression in different intestinal segments of cobia, Rachycentron canadum

AbstractA 4‐week feeding trial was conducted using five groups of hybrid grouper (61.15 ± 0.15 g) to explore the potential effects of three methionine (Met) sources. Five isonitrogenous and isolipidic diets were formulated that included a fishmeal (FM) diet; nonsupplemented (NS) diet; or NS diets with the addition of the L‐methionine (L‐Met), DL‐methionine (DL‐Met), or coated Met (Co‐Met) to obtain the same Met level as the FM diet. Fish were randomly distributed into sea cages (30 fish per cage). Weight gain and specific growth rate in the DL‐Met group and FM group were significantly higher than those in all other groups (p &lt; .05). In the proximal and distal intestines, of the 20 gene and time combinations (10 per gene), there were 14 combinations (70%) in which there were no significant differences in gene expression levels between the FM and DL‐Met groups (p &gt; .05). The main reason for the same growth effect between the DL‐Met and FM groups may be attributed to the synchronized absorption at most time points after feeding, which had similar expression patterns of B0AT1 and ASCT2 of the proximal and distal intestines between two groups.

Relationship between IL10 and PD-L1 in Liver Hepatocellular Carcinoma Tissue and Cell Lines

Background Despite the large-scale clinical application of programmed death-ligand 1 (PD-L1) monoclonal antibody, reduction in its clinical response rate has become a gradual problem. As such, use of PD-L1 monoclonal antibody in combination with other anticarcinoma drugs has been the main strategy in improving its efficacy. Interleukin 10 (IL10) is a recognized inflammatory and immunosuppressive factor. Previous studies have suggested that there is a link between PD-L1 and IL10. Objective This study was aimed at clarifying the relationship between PD-L1 and IL10 in liver hepatocellular carcinoma (LIHC) and whether IL10 enhances the efficacy of PD-L1 inhibitor. Methods Expression levels of PD-L1 and IL10 in carcinoma and adjacent tissues were tested by immunochemistry, Western blotting, and RT-PCR. Survival duration and follow-up data of each patient were recorded. LIHC cell lines Bel7405 and MHCC 97-H were used for in vitro experiments. Exogenous IL10 and anti-IL10 were added to cell supernatant. Expression level of PD-L1 in the LIHC cell lines was determined using Western blotting and ELISA. CCK8 and transwell assays were adopted to examine the effect of PD-L1 combined with IL10 on proliferation, invasion, and metastasis of LIHC cells. Results The survival period of patients with low expression of IL10 was longer than that of patients with high expression (P = 0.01). Overexpression of PD-L1 increased the IL10 and Met levels in LIHC tissues and cell lines. IL10 downregulated the expression level of PD-L1 and enhanced the efficacy of crizotinib via the Met signaling pathway in the LIHC cells. Conclusions A combination of IL10 and PD-L1 inhibitor holds great promise as an effective treatment for LIHC.

Modelling Accumulation of Respiratory-CO2 in Closed Rooms Leading to Decision-Making on Room Occupancy

A model predicting time required to attain undesired levels of respiratory-CO2 in closed rooms is described. The model works under the following assumptions: (1) room air is well-mixed, (2) indoor CO2 does not exchange with outdoor CO2, (3) there is no effect of individual occupants on CO2 exhalation rate of other occupants, (4) there is no indoor CO2 sink and all exhaled CO2 end up increasing CO2 concentration in the room, (5) apart from respiration, there is no other source of indoor CO2, (6) breathing rates of occupants are constant throughout the period of occupation of room. The model makes use of anthropocentric parameters like body weight, height, du bois surface area, MET levels, etc., to calculate dedicated individual CO2 exhalation rate and uses room volume and number of occupants to predict time required to reach user-earmarked levels of CO2. A model run showed that in a closed room of 12 × 12 × 10 m3, respiration by one person at rest (65 kg body weight, 1.7 m height, basal respiratory quotient of 0.83) would take 4.37 h to reach 2000 ppmV indoor CO2 when background indoor CO2 level was 380 ppmV. This model would help allocating desired number of occupants in closed rooms to help avoid building up of undesirable levels of CO2 in poorly ventilated offices, schools, hospitals or households that might frequently experience high levels of indoor CO2, undermining health and performance of occupants, patients and workers.

Predicting military working dog core temperature during exertional heat strain: Validation of a Canine Thermal Model.

Military working dogs (MWDs) operate under a wide range of conditions, including hot environments. Predicting how long a MWD can safely work without overheating is important for both health and performance. A Canine Thermal Model (CTM) was developed to predict core temperature (Tc) of MWDs. The CTM calculates heat storage from the balance of heat production from metabolism and heat exchange with the environment. Inputs to the CTM are: meteorological conditions (ambient temperature, relative humidity, solar radiation and wind speed), physical characteristics of the dog (mass, length), and metabolic activity (MET level, estimated from accelerometer data). The CTM was validated against Tc measured in 23 MWDs during training sessions (11.6±5.0min (mean±standard deviation), range 4-26min) in October (24°C, 52% RH), March (14°C, 74% RH), or August (28°C, 64% RH), and 24 kennel MWDs during a standard exercise walk (11.4±3.3min, range 5.6-18min) in July (26°C, 77% RH). The CTM was considered acceptable if predicted Tc was within ±0.5°C of measured Tc at the end of exercise. Compared to Tc at the end of training sessions (39.8±0.6°C, range 38.4-41.1°C) and exercise walks (40.0±0.7°C, range 38.9-41.4°C), the CTM-predicted Tc was within ±0.5°C for 71 of 84 cases (85%) and 19 of 24 cases (79%), respectively. The mean difference between CTM-predicted and measured final Tc during training was -0.04±0.43°C, with 80 of 84 cases (95%) within the range of ±2 SD (Bland Altman comparison). During exercise walks the mean difference was -0.15°C±0.57, with 23 of 24 cases (96%) within ±2 SD. These results support the use of the CTM to predict Tc of MWDs for the types of physical activities described above.

Suppressed Methionine γ-Lyase Expression Causes Hyperaccumulation of S-Methylmethionine in Soybean Seeds.

Several soybean (Glycine max) germplasms, such as Nishiyamahitashi 98-5 (NH), have an intense seaweed-like flavor after cooking because of their high seed S-methylmethionine (SMM) content. In this study, we compared the amounts of amino acids in the phloem sap, leaves, pods, and seeds between NH and the common soybean cultivar Fukuyutaka. This revealed a comparably higher SMM content alongside a higher free Met content in NH seeds, suggesting that the SMM-hyperaccumulation phenotype of NH soybean was related to Met metabolism in seeds. To investigate the molecular mechanism behind SMM hyperaccumulation, we examined the phenotype-associated gene locus in NH plants. Analyses of the quantitative trait loci in segregated offspring of the cross between NH and the common soybean cultivar Williams 82 indicated that one locus on chromosome 10 explains 71.4% of SMM hyperaccumulation. Subsequent fine-mapping revealed that a transposon insertion into the intron of a gene, Glyma.10g172700, is associated with the SMM-hyperaccumulation phenotype. The Glyma.10g172700-encoded recombinant protein showed Met-γ-lyase (MGL) activity in vitro, and the transposon-insertion mutation in NH efficiently suppressed Glyma.10g172700 expression in developing seeds. Exogenous administration of Met to sections of developing soybean seeds resulted in transient increases in Met levels, followed by continuous increases in SMM concentrations, which was likely caused by Met methyltransferase activity in the seeds. Accordingly, we propose that the SMM-hyperaccumulation phenotype is caused by suppressed MGL expression in developing soybean seeds, resulting in transient accumulation of Met, which is converted into SMM to avoid the harmful effects caused by excess free Met.

A Structural Model of Social Determinants of the Metabolic Syndrome.

The metabolic syndrome (MetS) refers to a cluster of interrelated physiological characteristics that are associated with an increased risk of cardiovascular disease and diabetes. While the clinical usefulness of the MetS has been the subject of controversy for years, increasingly sophisticated methods are being used to measure the concept. Study of community health center patients who were not diabetic; study group was evenly divided between Black and White adults. Latent MetS score and MetS status based on the five-point scale developed by the National Cholesterol Education Panel (NCEP). Structural equation modeling of MetS incorporating the effects of race/ethnicity, racial discrimination, socioeconomic position (SEP), and selected mediating variables. The largest influences on latent MetS scores were SEP (negative relationship) and male gender (higher scores for men). Two mediating variables, physical activity and stress-related eating, had smaller impacts. Self-reported racial discrimination was associated with cynical hostility but did not influence the MetS level among nondiabetics. Despite higher NCEP scores and MetS prevalence rates for Blacks compared with Whites, race did not have direct effect on MetS levels when adjusted for the other characteristics in our model. Neither race nor self-reported racial discrimination had direct effects on MetS level in our structural model. The large effects of socioeconomic position and male gender were not mediated by the other variables in the model.

Influence of low-protein diet with different levels of amino acids on laying hen performance, quality and egg composition.

The present study aimed to investigate the consequences of dietary levels of crude protein (CP) and total sulfur amino acids (TSAA, Met+Cys) on productive performance, egg quality and egg components for Lohmann Brown laying hens through 18-34 weeks of age. A 2×3 factorial design experiment was conducted using two levels of CP (16 and 18 %) and three levels of Met+ Cys (0.67, 0.72 and 0.77 %). A total of 144 Lohmann Brown laying hens at 18 weeks of age were randomly divided into 6 treatment groups. The best values of final body weight and body weight change were recorded by the hens fed 18 % CP diet. Increasing dietary CP up to 18 % accompanied with the best (P> 0.01) feed conversion, egg weight and egg mass. The combination between low-CP diet (16 %) and 0.72 % Met+ Cys gave the best percentage of egg production. The majority of egg quality traits were not significantly altered by dietary treatments. The interaction between CP and Met+Cys levels had a statistical (P>0.01) impact on egg content of moisture and total solids only. It could be concluded that the best production criteria could be obtained by using 0.72% Met+Cys. Moreover, dietary level of 16 or 18 % CP with 0.72% Met+Cys is recommended for feeding Lohmann hens.

Effect of hydroxyproline supplementation on growth performance, body composition, amino acid profiles, blood‐biochemistry and collagen synthesis of juvenile chu's croaker ( Nibea coibor )

Hydroxyproline (Hyp) may play an important role in collagen metabolism, as it is almost exclusively found in collagen. To examine this possibility, a 56-day feeding trial was conducted to evaluate the effect of graded supplementaries of Hyp (0, 2.5, 5, 7.5, 10 and 12.5 g/kg dry diet weight) on growth performance, feed utilization, biochemical composition and collagen synthesis of chu's croaker, Nibea coibor (13.6 ± 0.28 g). The growth performance and feed utilization were improved with increased levels of dietary Hyp, reaching a maximum at 5 g/kg (diet H2) followed by a slight decrease. Polynomial regression analysis showed that the maximum specific growth rate (SGR) was attained at 7.177 g/kg dietary Hyp. Increasing levels of Hyp did not affect body composition of juvenile Nibea coibor. However, dietary Hyp supplementation significantly affected the levels of Leu, Ile, Met, Lys, Ser, Glu and Pro in muscle and the levels of Met, Lys, Glu, Pro and Gly in swim bladder. The serum calcium (SC) level decreased significantly with increasing levels of dietary Hyp. However, the triglycerides (TG) and total cholesterol (T-CH) levels in serum and liver were relatively stable. Importantly, the acid-soluble collagen (ASC) and total collagen (TC) levels in swim bladder increased significantly initially and then decreased after reaching a maximum. Polynomial regression analysis revealed that the maximum TC level in swim bladder was attained at 9.736 g/kg of dietary Hyp. Collectively, these results suggest that the appropriate provision of hydroxyproline is essential for maximal collagen synthesis and growth.

Alterations in methionine to homocysteine ratio in individuals with first-episode psychosis and those with at-risk mental state

BackgroundDisturbance of the methionine (Met) cycle, which produces Met from homocysteine (Hcy), is suggested to be involved in several diseases, including psychiatric disorders. This study was aimed to investigate both levels of Met and Hcy in serum from individuals with first-episode psychosis (FEP) and individuals with at-risk mental state (ARMS). MethodWe measured serum Met and Hcy levels in individuals with FEP (n = 13) and ARMS (n = 30) using HPLC with fluorescence detection and LC-ESI-MS/MS. Met and Hcy levels in healthy controls (n = 41) were also measured. Differences between the 3 groups were analyzed by one-way analysis of variance (ANOVA) with Bonferroni correction. ResultsSerum Met levels were decreased (p = 0.038) and Hcy levels were increased (p = 0.017) in the FEP group. Hcy levels were also significantly increased compared to the ARMS group (p = 0.016), while Met levels were not significantly different between the FEP and ARMS groups. A significant decrease in the Met to Hcy ratio (Met/Hcy) was observed in the FEP group compared to both the control (p = 4.58 × 10−4) and ARMS (p = 8.07 × 10−3) groups. Furthermore, Met/Hcy ratio was correlated with Positive and Negative Syndrome Scale, especially positive scores (p = 5.90 × 10−5). ConclusionTaken together, these data indicate that a decrease in the serum Met/Hcy ratio may be a risk factor for developing psychosis during the transition from ARMS to FEP, and may prove to be a useful marker of the phase between ARMS and FEP.