Levels Of Threonine Research Articles

Interaction effects of glycine equivalent and standardized ileal digestible threonine in low protein diets for broiler grower chickens.

This study aims to investigate the interactive effect of a glycine equivalent (Glyequi) and standardized ileal digestible threonine (SID Thr) levels in low crude protein diets on performance, blood biochemistry, pectoral muscular creatine content and oxidative stability of meat in broiler chickens from 21 to 42 days. A total of 1,500, twenty-one-day-old Cobb-Vantress male broiler chickens were distributed in a completely randomized 5×3 factorial arrangement of Glyequi×SID Thr with five replicates of 20 birds each. Fifteen dietary treatments of 16.5% CP were formulated to contain five levels of total Glyequi (1.16%, 1.26%, 1.36%, 1.46%, and 1.56%) and three levels of SID Thr (0.58%; 0.68% and 0.78%). Interaction effects (p<0.05) of Glyequi and SID Thr levels were observed for weight gain, carcass yield, pectoral muscular creatine content and serum uric acid. Higher levels of Glyequi increased (p = 0.040) weight gain in 0.58% and 0.68% SID Thr diets compare to the 0.78% SID Thr diet. The SID Thr level at 0.68% improved (p = 0.040) feed conversion compared to other SID Thr diets. Levels of Glyequi equal to or above 1.26% in diets with 0.78% SID Thr resulted in birds with higher (p = 0.033) pectoral muscular creatine content. The breast meat yield observed in the 0.68% SID Thr diet was higher (p = 0.05) compared to the 0.58% SID Thr diet. There was a quadratic effect of Glyequi levels for pectoral pectoral muscular creatine content (p = 0.008), breast meat yield (p = 0.030), and serum total protein concentrations (p = 0.040), and the optimal levels were estimated to be 1.47%, 1.35%, and 1.40% Glyequi, respectively. The lowest (p = 0.050) concentration of malondialdehyde in the breast meat was found in 0.68% SID Thr diets at 1.36% Glyequi. The minimum dietary level of Glyequi needed to improve performance in low crude protein diets is 1.26% with adequate SID Thr levels for broiler chickens.

Integrated UHPLC-MS untargeted metabolomics and gut microbe metabolism pathway-targeted metabolomics to reveal the prevention mechanism of Gushudan on kidney-yang-deficiency-syndrome rats

Gushudan (GSD) was a traditional Chinese prescription with the remarkable effect of kidney-tonifying and bone-strengthening. However, the potential prevention mechanisms of the GSD on kidney-yang-deficiency-syndrome (KYDS) and its regulation on gut microbe metabolism still need to be further systematically investigated. This study established untargeted urinary metabolomics based on RP/HILIC-UHPLC-Q-Orbitrap HRMS and combined with multivariate statistical analysis to discover differential metabolites and key metabolic pathways. And the gut microbe metabolism pathway-targeted metabolomic based on HILIC-UHPLC-MS/MS was developed and validated to simultaneously determine 15 gut microbe-mediated metabolites in urine samples from the control group (CON), KYDS model group (MOD), GSD-treatment group (GSD) and positive group (POS). The results showed that a total of 36 differential metabolites were discovered in untargeted metabolomics. These differential metabolites included proline, cytosine, butyric acid and nicotinic acid, which were primarily involved in the gut microbe metabolism, amino acid metabolism, energy metabolism and nucleotide metabolism. And GSD played a role in preventing KYDS by regulating these metabolic pathways. The targeted metabolomics found that the levels of 10 gut microbe-mediated metabolites had significant differences in different groups. Among them, compared with the CON group, the levels of lysine, tryptophan, phenylacetylglycine and hippuric acid were increased in the MOD group, while the levels of threonine, leucine, dimethylamine, trimethylamine, succinic acid and butyric acid were decreased, which verified the disorders of gut microbe metabolism in the KYDS rats and GSD had a significant regulatory effect on this disorder. As well as by comparing analysis, it was found that the experimental results were consistent with previous metabolomics and microbiomics of fecal samples. Therefore, this integrated strategy of untargeted and targeted metabolomics not only elucidated the potential prevention mechanism of GSD on KYDS, but also provided a scientific basis for GSD preventing KYDS via the “gut-kidney” axis.

Evaluation of Dietary Essential Amino Acid Supplementation on Growth, Digestive Capacity, Antioxidant, and Intestine Health of the Juvenile Redclaw Crayfish, Cherax quadricarinatus.

The present study was an 8-week feeding trial investigating the effects of lysine and threonine supplementation in vegetable-based diets on growth, antioxidative capacity, and gut microbiota of juvenile redclaw crayfish, Cherax quadricarinatus (initial weight 11.52 ± 0.23 g). The lysine and threonine were supplemented to formulate five isonitrogenous (37%) and isolipidic (9%) diets containing 0% (control), 0.2% lysine (L0.2), 0.2% threonine (T0.2), 0.4% lysine (L0.4), and 0.4% threonine (T0.4), respectively. Compared to the control, weight gain rate (WGR) and specific growth rate (SGR) of C. quadricarinatus significantly increased with increasing dietary lysine and threonine supplementation from 0.2% to 0.4% (P < 0.05). Hepatopancreas trypsin activity significantly increased with increasing levels of lysine and threonine in diets (P < 0.05). However, the pepsin, lipase, and amylase activities were not affected by dietary levels of lysine and threonine (P > 0.05). Compared with the control, crayfish in T0.4 and L0.4 showed significantly higher glutathione peroxidase (GPx) activity (P < 0.05), lower alanine aminotransferase (ALT) activity, and lower malondialdehyde (MDA) content (P < 0.05). Supplementation with 0.4% lysine significantly changed the composition of the gut microbiota (P < 0.05), which showed a significantly increased relative abundance of Proteobacteria and decreased Firmicutes, Actinomycetes, and Pontomyces (P < 0.05). The PICRUSt analysis demonstrated that the abundance of the metabolism and cellular processes pathways in the L0.4 group were markedly decreased compared with the control (P < 0.05). Meanwhile, a tighter interaction of the microbiota community in crayfish was observed in the T0.4 experimental group. In conclusion, these results suggested that dietary supplementation with 0.4% threonine could significantly promote growth and improve microbial health in juvenile C. quadricarinatus.

Effect of Protease Combined With Heat Treatment on the Stability of Proteins in Liqueur Wine

Background: Protein instability has been reported to be an important cause of haze in white wines; to investigate the feasibility of protease as a substitute for bentonite in the protein stability of white grape liqueurs, the effect of protease combined with heat treatment on the composition and protein stability of liqueur wines was investigated by chemical analysis, sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS‐PAGE), and amino acid analysis.Results: The results showed that the contents of total acid, volatile acid, pH, and glycerol were not significantly different from the blank control; the effect on total protein content and thermal stability were similar to the bentonite treatment; the L∗, b∗, and values of liqueur wines increased by 5.59%, 4.33%, and 4.33% after protease combined with heat treatment (p &lt; 0.05); SDS‐PAGE results confirmed that protease combined with heat treatment had good hydrolysis for thaumatin‐like proteins (TLPs) and chitinases (CHIs) in liqueur wines. Amino acid analysis revealed that the levels of threonine, serine, tyrosine, arginine, and proline had increased, respectively, and isoleucine (1.26 mg/L) and leucine (1.16 mg/L) were newly detected after protease combined with heat treatment. Particle size analysis showed that the protease combined with heat treatment had less effect on the particle size distribution of the wines.Conclusion: Protease combined with heat treatment had a certain protein stabilizing effect and had no significant negative impact on other nutrients of liqueur wines. Thus, it can be used as an alternative to bentonite for the protein stabilization of liqueur wines.

Screening key sorghum germplasms for low-nitrogen tolerance at the seedling stage and identifying from the carbon and nitrogen metabolism.

Sorghum (Sorghum bicolor L.) can withstand drought and heat stress and efficiently utilize water and nutrients. However, the underlying mechanism of its tolerance to low-nitrogen (N) stress remains poorly understood. This study assessed low-N tolerance in 100 sorghum-inbred lines and identified those with exceptional resilience. Principal component analysis, Pearson's correlation, and Y value analysis were used to examine various seedling growth metrics, including plant and root dimensions, biomass, chlorophyll content, root N content, shoot N content, and root/shoot ratio. The genotypes were categorized into four distinct groups based on their respective Y values, revealing a spectrum from highly tolerant to sensitive. Low-N-tolerant sorghum lines maintained higher photosynthetic rates and exhibited increased enzymatic activities linked to carbon and N metabolism in the leaves and roots. Furthermore, low-N-tolerant genotypes had higher levels of key amino acids, including cystine, glycine, histidine, isoleucine, leucine, phenylalanine, threonine, and tyrosine, indicating a robust internal metabolic response to N deficiency. This study provides a comprehensive and reliable approach for the evaluation of sorghum tolerance to low-N environments, sheds light on its morphological and physiological adaptations, and provides valuable insights for future breeding programs and agricultural practices.

Investigating the Impact of Vitamin A and Amino Acids on Immune Responses in Celiac Disease Patients.

Amino acids (AAs) and vitamin imbalances are observed in celiac disease (CD). This study evaluated the plasma profile of vitamin A and AAs and the expression level of IL-2, IL-4, IL-10, IL-12 and TGFβ in CD patients. A total of 60 children and adults with CD and 40 healthy controls (HCs) were included. The plasma profile of Vitamin A and AAs and the mRNA expression levels of target genes were assessed. Active adult patients exhibited a decrease in Vitamin A levels (p = 0.04) and an increase in IL-2 (p = 0.008) and IL-12 (p = 0.007) mRNA expression compared to the HCs. The treated adult patients showed elevated Serine (p = 0.003) and Glycine (p = 0.04) levels, as well as increased IL-12 (p < 0.0001) mRNA expression, and a decrease in Tryptophan (p = 0.04) levels relative to the controls. Additionally, the treated adult patients had higher plasma levels of Threonine compared to both the active (p = 0.04) and control (p = 0.02) subjects, and the increased mRNA expression of IL-4 (p = 0.01) in comparison to the active patients. In active children with CD, the IL-2 mRNA level was found to be higher than in the controls (p < 0.0001) and in the treated children (p = 0.005). The treated children with CD exhibited decreased plasma levels of Tryptophan (p = 0.01) and Isoleucine (p = 0.01) relative to the controls, and the increased mRNA expression of TGFβ (p = 0.04) relative to the active patients. Elevated levels of specific AAs (Serine, Glycine, Threonine) in the treated CD patients suggested their potential to improve intestinal damage and inflammation, while decreased levels of Tryptophan and Isoleucine highlighted the need for dietary intervention.

Platelets characteristics in patients with coronary artery disease and atrial fibrillation

The aim. To estimate the connections between platelet morphological characteristics and amino acids (AA) profile in patients with coronary artery disease (CAD) and atrial fibrillation (AF).&#x0D; Materials and methods. 300 patients were included in the study. They were divided into 3 groups: first (CAD) – 149 patients with CAD but without arrhythmias, second (CAD+AF) – 124 patients with CAD and AF paroxysm and control group – 27 patients without CAD and arrhythmias. Platelets AA level was detected by method of ion exchange liquid column chromatography. Total platelet count (PC), mean platelet volume (MPV), platelets distribution width (PDW), platelet-to-leukocyte (PLR) were obtained from common blood count.&#x0D; Results. Significant decline of PC and rise of MPV and PLR ratio was found in CAD patients and AF paroxysm in comparison with group with CAD without arrhythmia, p &lt; 0.05. Significant increase of isoleucine, leucine and decrease of threonine, serine, glycine, valine levels was found, changes in branched chain amino acids (rise of Isoleucine + Leucine / Valine ratio) and Glycine + Serine (decline Glycine + Serine sum) metabolism were revealed in CAD patients and AF paroxysm in comparison with group with CAD without arrhythmia, p &lt; 0.05. Phenylalanine / Tyrosine ratio was significantly elevated in CAD patients with and without AF, p &lt; 0.05.&#x0D; Taurine, serine, and glycine correlated with platelets morphological characteristics: PC (r = 0.714, r = 0.732 and r = 0.340 consequently), MPV (r = -0.724, r = -0.390 and r = -0.571 consequently), PDW (r = -0.666 and r = -0.364 consequently) and PLR (r = 0.586 and r = 0.648 consequently), p &lt; 0.05. Platelets glycine (AUC = 0.8760), valine (AUC = 0.8707), leucine (AUC = 0.8267) and threonine (AUC = 0.8213) levels are closely connected with AF paroxysm in CAD patients by ROC-analysis results, p &lt; 0.05.&#x0D; Platelets amino acids combinations: Glycine + 0.6 × Valine (AUC = 0.9987), Threonine – 3.6 × Leucine (AUC = 0.9040) were found in prediction AF paroxysm for CAD patients by ROC-analysis results, p &lt; 0.05.&#x0D; Conclusions. Connections between platelets morphology and AA profile violations in patients with CAD and AF paroxysm were found in our study.

Optimization of the flip angles of narrow-band editing pulses in J-difference edited MRS of lactate at 3T.

Application of highly selective editing RF pulses provides a means of minimizing co-editing of contaminants in J-difference MRS (MEGA), but it causes reduction in editing yield. We examined the flip angles (FAs) of narrow-band editing pulses to maximize the lactate edited signal with minimal co-editing of threonine. The effect of editing-pulse FA on the editing performance was examined, with numerical and phantom analyses, for bandwidths of 17.6-300 Hz in MEGA-PRESS editing of lactate at 3T. The FA and envelope of 46 ms Gaussian editing pulses were tailored to maximize the lactate edited signal at 1.3 ppm and minimize co-editing of threonine. The optimized editing-pulse FA MEGA scheme was tested in brain tumor patients. Simulation and phantom data indicated that the optimum FA of MEGA editing pulses is progressively larger than 180° as the editing-pulse bandwidth decreases. For 46 ms long 17.6 Hz bandwidth Gaussian pulses and other given sequence parameters, the lactate edited signal was maximum at the first and second editing-pulse FAs of 241° and 249°, respectively. The edit-on and difference-edited lactate peak areas of the optimized FA MEGA were greater by 43% and 25% compared to the 180°-FA MEGA, respectively. In-vivo data confirmed the simulation and phantom results. The lesions of the brain tumor patients showed elevated lactate and physiological levels of threonine. The lactate MEGA editing yield is significantly increased with editing-pulse FA much larger than 180° when the editing-pulse bandwidth is comparable to the lactate quartet frequency width.

Serum metabolomic profiling unveils distinct sex-related metabolic patterns in NAFLD.

Obesity poses an increased risk for the onset of Nonalcoholic fatty liver disease (NAFLD). The influence of other factors, such as sex in the incidence and severity of this liver disease has not yet been fully elucidated. Thus, we aimed to identify the NAFLD serum metabolic signatures associated with sex in normal, overweight and obese patients and to associate the metabolite fluctuations across the increasing liver steatosis stages. Using nuclear magnetic resonance (NMR) serum samples of 210 NAFLD cases and control individuals diagnosed with liver U/S, our untargeted metabolomics enquiry provided a sex distinct metabolic bouquet. Increased levels of alanine, histidine and tyrosine are associated with severity of NAFLD in both men and women. Moreover, higher serum concentrations of valine, aspartic acid and mannose were positively associated with the progression of NAFLD among the male subjects, while a negative association was observed with the levels of creatine, phosphorylcholine and acetic acid. On the other hand, glucose was positively associated with the progression of NAFLD among the female subjects, while levels of threonine were negatively related. Fluctuations in ketone bodies acetoacetate and acetone were also observed among the female subjects probing a significant reduction in the circulatory levels of the former in NAFLD cases. A complex glycine response to hepatic steatosis of the female subjects deserves further investigation. Results of this study aspire to address the paucity of data on sex differences regarding NAFLD pathogenesis. Targeted circulatory metabolome measurements could be used as diagnostic markers for the distinct stages of NAFLD in each sex and eventually aid in the development of novel sex-related therapeutic options.

Effect of the Probiotic Bacillus subtilis DE-CA9TM on Fecal Scores, Serum Oxidative Stress Markers and Fecal and Serum Metabolome in Healthy Dogs.

There is increasing interest in the use of Bacillus species as probiotics since their spore-forming ability favors their survival in the acidic gastric environment over other probiotic species. The subsequent germination of B. subtilis to their vegetative form allows for their growth in the small intestine and may increase their beneficial effect on the host. B. subtilis strains have also previously been shown to have beneficial effects in humans and production animals, however, no reports are available so far on their use in companion animals. The goal of this study was therefore to investigate the daily administration of 1 × 109 cfu DE-CA9TM orally per day versus placebo on health parameters, fecal scores, fecal microbiome, fecal metabolomics, as well as serum metabolomics and oxidative stress markers in ten healthy Beagle dogs in a parallel, randomized, prospective, placebo-controlled design over a period of 45 days. DE-CA9TM decreased the oxidative status compared to controls for advanced oxidation protein products (AOPP), thiobarbituric acid reactive substances (TBARS) and reactive oxygen metabolites (d-ROMS), suggesting an antioxidant effect of the treatment. Fecal metabolomics revealed a significant reduction in metabolites associated with tryptophan metabolism in the DE-CA9TM-treated group. DE-CA9TM also significantly decreased phenylalanine and homocysteine and increased homoserine and threonine levels. Amino acid metabolism was also affected in the serum metabolome, with increased levels of urea and cadaverine, and reductions in N-acetylornithine in DE-CA9TM compared to controls. Similarly, changes in essential amino acids were observed, with a significant increase in tryptophan and lysine levels and a decrease in homocysteine. An increase in serum guanine and deoxyuridine was also detected, with a decrease in beta-alanine in the animals that ingested DE-CA9TM. Data generated throughout this study suggest that the daily administration of 1 × 109 cfu of DE-CA9TM in healthy Beagle dogs is safe and does not affect markers of general health and fecal scores. Furthermore, DE-CA9TM administration had a potential positive effect on some serum markers of oxidative stress, and protein and lipid metabolism in serum and feces.

Differences in rectal amino acid levels determine bacteria-originated sex pheromone specificity in two closely related flies

Sex pheromones are widely used by insects as a reproductive isolating mechanism to attract conspecifics and repel heterospecifics. Although researchers have obtained extensive knowledge about sex pheromones, little is known about the differentiation mechanism of sex pheromones in closely related species. Using Bactrocera dorsalis and Bactrocera cucurbitae as the study model, we investigated how the male-borne sex pheromones are different. The results demonstrated that both 2,3,5-trimethylpyrazine (TMP) and 2,3,5,6-tetramethylpyrazine (TTMP) were sex pheromones produced by rectal Bacillus in the two flies. However, the TMP/TTMP ratios were reversed, indicating sex pheromone specificity in the two flies. Bacterial fermentation results showed that different threonine and glycine levels were responsible for the preference of rectal Bacillus to produce TMP or TTMP. Accordingly, threonine (glycine) levels and the expression of the threonine and glycine coding genes were significantly different between B. dorsalis and B. cucurbitae. In vivo assays confirmed that increased rectal glycine and threonine levels by amino acid feeding could significantly decrease the TMP/TTMP ratios and result in significantly decreased mating abilities in the studied flies. Meanwhile, decreased rectal glycine and threonine levels due to RNAi of the glycine and threonine coding genes was found to significantly increase the TMP/TTMP ratios and result in significantly decreased mating abilities. The study contributes to the new insight that insects and their symbionts can jointly regulate sex pheromone specificity in insects, and in turn, this helps us to better understand how the evolution of chemical communication affects speciation.

The Association between Macrosomia and Amino Acids' Levels in Maternal and Cord Sera: A Case-Control Study.

In the case-control study, 78 pairs of mothers and newborns were recruited from December 2016 to November 2019. Participants were divided into the macrosomia group (BW ≥ 4000 g, n = 39) and the control group (BW between 2500 g and 3999 g, n = 39) according to the birth weight (BW) of newborns. Maternal vein blood samples were collected before delivery and cord vein blood samples were collected after birth. The levels of amino acids in maternal and cord sera were measured by liquid chromatography and mass spectrometry (LC-MS/MS) in the year 2021. The difference in amino acid levels in maternal and cord sera between the two groups was compared, and the contribution of each amino acid to the difference between the two groups was analyzed. Unconditional logistic regression analysis was used to test the relationship between macrosomia and amino acids. In maternal serum during the antepartum, the levels of asparagine, glutamine, methionine, alanine, and threonine in the macrosomia group were higher but arginine was lower than that in the control group (p < 0.05). In cord serum, the levels of lysine, histidine, phenylalanine, arginine, tryptophan, valine, isoleucine, glutamate, tyrosine, and total essential amino acid (EAA) in the macrosomia group were lower while glutamine was higher than that in the control group (p < 0.05). The ratios of EAA, valine, threonine, methionine, tryptophan, and alanine in maternal serum to those in cord serum were higher, while the ratio of glutamine was lower in the macrosomia group (p < 0.05). Arginine and threonine in maternal serum and glutamate, glutamine, and histidine in cord serum were associated with macrosomia (p < 0.05). Most of the amino acid levels in the maternal sera of the macrosomia group are higher than those in the control group, while most of the amino acids' levels in the cord sera of the macrosomia group are lower than those in the control group. The ratios of some amino acids in maternal serum to those in cord serum were different between the two groups. Arginine and threonine in maternal serum and glutamate, glutamine, and histidine in cord serum are closely related to macrosomia.

Influence of lactic-acid bacteria feed supplementation on free amino acid levels in serum and feces of rainbow trout (Oncorhynchus mykiss, Walbaum 1792)

IntroductionThe influence of intestinal microbiota, particularly lactic-acid bacteria, on digestion and nutrient metabolic activities has been extensively studied. In this research, we investigated the effects of supplementing the feed of rainbow trout (O. mykiss) with P. acidilactici or L. lactis probiotics. A Control group without probiotic supplementation was also included. The study aimed to evaluate growth, feed conversion indices, free amino acid levels in serum and feces, and the relative gene expression of amino acid solute carrier transporters (SLC).MethodsRainbow trout weighing 73.9±10 g were fed with a basal commercial diet supplemented with mono-strains of P. acidilactici or L. lactis at a dosage of 5 x 108 CFU per gram of feed for 60 days. The trout were reared in 100-liter tanks with independent closed recirculation systems, with a water replacement rate of 80% of the total volume daily and a controlled temperature of 15 ± 0.3 °C. The proximate composition of the basal diet consisted of crude protein (49.8%), fat (32.1%), fiber (1.31%), ash (13%), and moisture (8.3%) on a dry matter basis. The diet was provided at a rate of 2% of bodyweight per day.ResultsNo significant differences (p &amp;gt; 0.05) were observed in growth and feed conversion indices between the experimental groups. However, significant differences in free amino acid levels in feces and serum samples (p ≤ 0.05) were observed. The P. acidilactici group exhibited significantly higher levels of glutamate, lysine, proline, and tyrosine in feces samples, and higher levels of arginine, iso/leucine, phenylalanine, proline, serine, threonine, and valine in serum samples compared to the Control group. Additionally, the supplemented probiotic groups showed significant downregulation (p ≤ 0.05) of theslc6a19 and slc7a9 genes, which encode transporters for neutral and cationic amino acids.DiscussionThe autochthonous rainbow trout strain, P. acidilactici, demonstrated more pronounced effects on amino acid levels in feces and serum compared to the non-autochthonous L. lactis strain. However, the increased amino acid levels, particularly in the serum, resulting from P. acidilactici supplementation, did not lead to improved trout growth or feed conversion. Nonetheless, lactic-acid bacteria supplementation induced measurable metabolic effects, as evidenced by elevated levels of specific amino acids in the serum and feces.Future research should focus on evaluating these probiotic effects using specialized diets and considering the observed metabolic effects in this study.

NMR metabolomics in bladder cancer: Identification and monitoring of serum biomarkers during Pt-based treatment.

3057 Background: To date, predictive and prognostic biomarkers for Bladder Cancer (BC) are lacking. Metabolomics, the study of small molecules involved in metabolism, aims to identify diagnostic, predictive and prognostic biomarkers. Overall, BC shows perturbations of various metabolic pathways, involved in biochemical reactions essential for energy production and for the maintenance of the REDOX balance, as well as in the metabolism of purines and pyrimidines. The main objective of this study is to characterize the serum metabolic profile of patients with BC undergoing platinum-based chemotherapy (Pt-CT), to identify the alterations induced by CT and evaluate the associated deregulated metabolic pathways, in order to identify potential biomarkers, prognostic and predictive of response to treatment. Methods: We enrolled patients with BC undergoing Pt-CT in different settings (neoadjuvant, adjuvant or metastatic). For each patient, a blood sample was collected before the start of each CT cycle (T0, T1, Tn). Metabolomic analysis was performed using the Bruker Avance 600 spectrometer. At baseline (T0), the metabolomic profiles of BC patients were compared with that of age- and sex-matched healthy controls. Major metabolites up- or down-regulated in patients with BC at baseline, were then monitored during CT (T1, Tn). Results: 14 patients were enrolled. When compared with age- and sex-matched healthy controls, patients with BC had elevated levels of acetate and acetone (ketone bodies), hypoxanthine, trimethylamine N-oxide (TMAO), glutamate, lactate, phenylalanine, and ornithine, and decreased levels of carnitine, choline, betaine, aspartate, threonine, 2-hydroxybutyrate, 2-aminobutyrate and histidine. When monitored during CT, hypoxanthine, glutamate, and aspartate levels increased; acetone, acetate and TMAO instead had a decreasing trend. Conclusions: The results of our pilot study confirm perturbations in several metabolic pathways: up-regulation of lactate, ketone bodies, hypoxanthine, phenylalanine, and glutamate levels in BC patients reflects altered glycolysis, fatty acid, purine, and amino acid metabolism, respectively. In addition, TMAO may play a role in the development of BC by promoting a pro-inflammatory and oxidative stress state. Furthermore, monitoring these metabolites could be a useful tool for predicting response to treatments. To our knowledge, there are no metabolomic studies that evaluated BC patients receiving CT and that included longitudinal monitoring to identify any changes in the metabolic profile induced by treatment.

Muscle Protein Synthesis with a Hybrid Dairy and Plant-Based Protein Blend (P4) Is Equal to Whey Protein in a Murine Ageing Model after Fasting.

P4, a specific combination of dairy proteins (whey and casein) and plant-based protein isolates (pea and soy), has been shown to provide a more balanced amino acid (AA) profile than its single constituent proteins; however, less is known about how this translates to muscle protein synthesis (MPS). The aim of this study was to investigate the effect of P4 compared to whey or casein against fasted control on MPS. C57BL/6J mice, aged 25 months, were fasted overnight, followed by oral gavage of either whey, P4, casein, or water as a fasted control. Thirty minutes after ingestion, puromycin (0.04 µmol∙g-1 bodyweight) was subcutaneously injected; 30-min thereafter, mice were sacrificed. MPS was measured by the SUnSET method, and signalling proteins were determined in the left-tibialis anterior (TA) muscle by the WES technique. AA composition was determined in plasma and right-TA muscle. Dried blood spots (DBS) were analysed for postprandial AA dynamics at 10, 20, 45, 60 min. MPS was 1.6-fold increased with whey (p = 0.006) and 1.5-fold with P4 compared to fasted (p = 0.008), while no change was seen with casein. This was confirmed by a significant increase of phosphorylated/total ratio of 4E-BP1 for both whey (p = 0.012) and P4 (p = 0.001). No changes were observed in p70S6K and mTOR phosphorylation/total ratio with whey or P4. Intramuscular leucine levels were lower for P4 (0.71 µmol∙g dry weight-1) compared to whey (0.97 µmol∙g dry weight-1) (p = 0.0007). Ten minutes postprandial, DBS showed significantly increased blood AA levels of BCAAs, histidine, lysine, threonine, arginine, and tyrosine for P4 versus fasted. In conclusion, a hybrid mix of dairy and plant-based proteins (P4) resulted in a MPS response that was similar to whey protein in aged mice after fasting. This suggests that other anabolic triggers beyond leucine or the well-balanced amino acid profile and bioavailability of the blend benefit stimulation of MPS.

Growth performance, liver and kidney functions, blood hormonal profile, and economic efficiency of broilers fed different levels of threonine supplementation during feed restriction

The objective of the existing investigation was to determine the effect of dietary inclusion of threonine amino acid at different levels during feed restriction on growth indices, liver and kidney function parameters, and some hormonal profiles along with economic indicators in broiler chickens. A total of 1,600 from 2 different breeds (800 Ross 308 and 800 Indian River) at 21-day-old age were incorporated. Chicks were randomly assigned into 2 main groups, control and feed-restricted (8 h/d), during the fourth week of age. Each main group was subdivided into 4 groups. The first group was fed a basal diet without adding extra threonine (100%), the second, third, and fourth groups were fed a basal diet with extra threonine levels of 110, 120, and 130%, respectively. Each subgroup consisted of 10 replicates of 10 birds. We noticed that the dietary inclusion of threonine at extra levels in the basal diets significantly enhanced final body weight, body weight gain, and better feed conversion ratio. This was mainly due to the enhanced levels of growth hormone (GH), insulin-like growth factor (IGF1), triiodothyronine (T3), and thyroxine (T4). Moreover, the lowest feed cost per kilogram body weight gain and improved return parameters were reported in control and feed-restricted birds fed higher levels of threonine than other groups. Also, a significant increase in alanine aminotransferase (ALT), aspartate aminotransferase (AST), and urea levels was observed in feed-restricted birds supplemented with 120 and 130% levels of threonine. Hence, we recommend supplementing threonine at levels of 120 and 130% in the diet of broilers to promote growth and profitability.

Serine metabolism during differentiation of human iPSC-derived astrocytes.

Astrocytes are essential players in development and functions, being particularly relevant as regulators of brain energy metabolism, ionic homeostasis, and synaptic transmission. They are also the major source of L-serine in the brain, which is synthesized from the glycolytic intermediate 3-phosphoglycerate through the phosphorylated pathway. L-serine is the precursor of the two main co-agonists of the N-methyl-D-aspartate receptor, glycine and D-serine. Strikingly, dysfunctions in both L- and D-serine metabolism are associated with neurological and psychiatric disorders. Here, we exploited a differentiation protocol, based on the generation of human mature astrocytes from neural stem cells, and investigated the modification of the proteomic and metabolomic profile during the differentiation process. We show that differentiated astrocytes are more similar to mature rather than to reactive ones, and that axogenesis and pyrimidine metabolism increase up to 30 days along with the folate cycle and sphingolipid metabolism. Consistent with the proliferation and cellular maturation processes that are taking place, also the intracellular level of L-serine, glycine, threonine, L- and D-aspartate (which level is unexpectedly higher than that of D-serine) show the same biosynthetic time course. A significant utilization of L-serine from the medium is apparent while glycine is first consumed and then released with a peak at 30 days, parallel to its intracellular level. These results underline how metabolism changes during astrocytes differentiation, highlight that D-serine synthesis is restricted in differentiated astrocytes, and provide a valuable model for developing potential novel therapeutic approaches to address brain diseases, especially the ones related to serine metabolism alterations.

L-threonine requirement of silver catfish (Rhamdia quelen): growth performance, body composition, plasma and liver metabolites

ABSTRACT A feeding trial was performed to evaluate the effects of dietary L-threonine supplementation on growth and body composition of fingerlings Rhamdia quelen (initial weight: 4.47 ± 0.39 g). Five diets (370 g/kg crude protein and 14.23 MJ / kg of digestible energy) containing levels of L-threonine (16.0, 22.0, 28.0, 34.0, 40.0 g threonine/kg protein) were fed to quadruplicate groups of fishes for 10 weeks. The analysed variables were influenced by the threonine levels. Fish fed with diet containing 16.0 g threonine/kg of CP showed lower growth and body deposition of nutrients. In addition to unsatisfactory performance, the fish subjected to lower levels of threonine presented higher hepatosomatic index scores and changes in the concentrations of some plasmatic metabolites. To determine the ideal level of threonine in the diet, the weight gain, specific growth rate and feed conversion ratio were subjected to broken-line and quadratic regression. The results showed indicate that a diet containing inadequate levels of threonine causes insufficient growth. Dietary threonine requirement of R. quelen was estimated between 24.5 and 32.5 g threonine/ kg of crude dietary protein, corresponding to 9.1 and 12.0 g/ kg threonine in the diet for the initial growth of silver catfish.

Effect of Increasing the Methionine Level and Reducing the Threonine Level in the Diet of Fast-Growing Rabbits.

The main aim of this work was to evaluate a novel combination of the first limiting amino acids (lysine, methionine, and threonine) in fast-growing rabbits (combination MHL, shown to minimise levels of plasmatic urea nitrogen in previous research, medium level of lysine, high level of methionine, and low level of threonine) and compare it with current recommendations (combination MMM, medium level of all amino acids). A total of 165 weaned rabbits (28 d old) from a paternal line selected for growth rate were used in the growth trial. The effect of the diet on apparent fecal digestibility, as well as the apparent and true ileal digestibility, were studied. Nutrient retention was also determined. Although no differences in digestibility between diets were observed, animals fed with Diet MHL improved the global average daily gain (+2.3 g/d; p = 0.0482) and feed conversion ratio (-0.10; p = 0.0229). Animals fed with Diet MMM reduced the protein-to-energy ratio retained (p = 0.0086). In conclusion, Diet MHL promoted an improvement in growth traits in a paternal line. Consequently, we propose its levels of 6.4, 5.4, and 5.0 g/kg DM of true ileal digestible lysine, methionine, and threonine, respectively.

Metabolomics analysis of follicular fluid in ovarian endometriosis women receiving progestin-primed ovary stimulation protocol for in vitro fertilization

This study aimed to investigate the metabolite profile and inflammatory state of follicular fluid (FF) in women with stage III–IV ovarian endometriosis (OE) who underwent in vitro fertilization (IVF). A cohort of 20 consecutive patients with OE were recruited and received progestin-primed ovary stimulation (PPOS) protocol (study group), while another 20 OE patients received one-month ultra-long term protocol (control group) for IVF in this prospective, nonrandomized study. FF samples were obtained from dominant follicles during oocyte retrieval, and liquid chromatography-mass spectrometry (LC–MS) was used to investigate the metabolites profile of FF. Results showed that significant increases in the levels of proline, arginine, threonine, and glycine in patients who received PPOS protocol compared to the control group (P < 0.05). A panel of three metabolites (proline, arginine, and threonine) was identified as specific biomarkers of OE patients using PPOS protocol. Additionally, levels of interleukin-1β, regulated on activation, normal T cell expressed and secreted, and tumor necrosis factor-α markedly decreased in women who received PPOS protocol compared to the control group (P < 0.05). In conclusion, PPOS protocol regulates the metabolism of several amino acids in the FF, which may play critical roles in the oocyte development and blastocyst formation, and their specific mechanism should be further elucidated.