Search

Creatine (Cr) supplementation is a well-established strategy to enhance gains in strength, lean body mass, and power from a period of resistance training. However, the effectiveness of creatyl-L-leucine (CLL), a purported Cr amide, is unknown. Therefore, the purpose of this study was to assess the effects of CLL on muscle Cr content. Twenty-nine healthy men (n = 17) and women (n = 12) consumed 5 g/day of either Cr monohydrate (n = 8; 28.5 ± 7.3 years, 172.1 ± 11.0 cm, 76.6 ± 10.7 kg), CLL (n = 11; 29.2 ± 9.3 years, 170.3 ± 10.5 cm, 71.9 ± 14.5 kg), or placebo (n = 10; 30.3 ± 6.9 years, 167.8 ± 9.9 cm, 69.9 ± 11.1 kg) for 14 days in a randomized, double-blind design. Participants completed three bouts of supervised resistance exercise per week. Muscle biopsies were collected before and after the intervention for quantification of muscle Cr. Cr monohydrate supplementation which significantly increased muscle Cr content with 14 days of supplementation. No changes in muscle Cr were observed for the placebo or CLL groups. Cr monohydrate supplementation is an effective strategy to augment muscle Cr content while CLL is not.

Spontaneous hypercortisolism (HC) is a common endocrine disease of senior dogs, often overlapping in selected clinical signs and hematologic and blood biochemical abnormalities with nonadrenal diseases (NADs). HC and NAD could differentially affect cortisol metabolism, which is a complex 10-enzymatic pathway process. HC might also affect blood and urine lactate levels through its effects on mitochondrial function. We aimed to differentiate between HC and NAD via a urinary cortisol metabolites and lactate panel. We prospectively recruited 7 healthy dogs and 18 dogs with HC, 15 with congestive heart failure (CHF), and 9 with NAD. We analyzed urine by gas chromatography–mass spectrometry and liquid chromatography–mass spectrometry. We normalized urinary lactate and cortisol metabolites to urine creatinine concentration, and then compared groups using a linear-mixed model and principal component (PC) analysis. A machine-learning classification algorithm generated a decision tree (DT) model for predicting HC. The least-squares means of normalized urinary 6β-hydroxycortisol and PC1 of the HC and CHF groups were higher than those of the healthy and NAD groups ( p = 0.05). Creatinine-normalized urinary 6β-hydroxycortisol had better sensitivity (Se, 0.78; 95% CI: 0.55–0.91), specificity (Sp, 0.89; 95% CI: 0.57–0.99), and a likelihood ratio (LR; 7), than the Se (0.72; 95% CI: 0.49–0.88), Sp (0.89; 95% CI: 0.57–0.99), and LR (6.5) of PC1 for distinguishing HC from NAD. Lactate and dihydrocortisone had the highest decreasing node-weighted impurity value and were considered the most important features in the DT model; dihydrocortisol had no role in determining whether a dog had HC.

Key points The ingestion of protein potentiates the stimulation of myofibrillar protein synthesis rates after an acute bout of resistance exercise. Protein supplementation (eating above the protein Recommended Dietary Allowance) during resistance training has been shown to maximize lean mass and strength gains in healthy young and older adults. Here, we assessed contractile, oxidative, and structural protein synthesis in skeletal muscle in response to a moderate or higher protein diet during the early adaptive phase of resistance training in middle-aged adults. We report that the stimulation of myofibrillar, mitochondrial, or collagen protein synthesis rates during 0-3 weeks of resistance training is not further enhanced by a higher protein diet. These results show that moderate protein diets are sufficient to support the skeletal muscle adaptive response during the early phase of a resistance training program. Abstract Protein ingestion augments muscle protein synthesis (MPS) rates acutely after resistance exercise and can offset age-related loss in muscle mass. Skeletal muscle contains a variety of protein pools, such as myofibrillar (contractile), mitochondrial (substrate oxidation), and collagen (structural support) proteins, and the sensitivity to nutrition and exercise seems to be dependent on the major protein fraction studied. However, it is unknown how free-living conditions of dietary protein density with habitual resistance exercise mediates muscle protein subfraction synthesis. Therefore, we investigated the effect of moderate (MOD: 1.06 ± 0.22 g·kg-1 ·d-1 ) or high (HIGH: 1.55 ± 0.25 g·kg-1 ·d-1 ) protein intake on daily MPS rates within the myofibrillar (MyoPS), mitochondrial (MitoPS), and collagen (CPS) protein fractions in middle-aged men and women (n = 20, 47 ± 1 y, BMI 28 ± 1 kg·m-2 ) during the early phase (0-3 wks) of a dietary counseling-controlled resistance training program. Participants were loaded with deuterated water, followed by daily maintenance doses throughout the intervention. Muscle biopsies were collected at baseline and after weeks 1, 2, and 3. MyoPS in the HIGH condition remained constant (P = 1.000), but MOD decreased over time (P = 0.023). MitoPS decreased after 0-3 wks when compared to 0-1 wks (P = 0.010) with no effects of protein intake (P = 0.827). A similar decline with no difference between groups (P = 0.323) was also observed for CPS (P = 0.007). Our results demonstrated that additional protein intake above moderate amounts does not potentiate the stimulation of longer-term MPS responses during the early stage of resistance training adaptations in middle-aged adults. This article is protected by copyright. All rights reserved.

Chlamydia trachomatis (CT) and Mycoplasma genitalium (MG) are two highly prevalent bacterial sexually transmitted infections (STIs) with a significant rate of co-infection in some populations. Vaginal metabolites are influenced by resident vaginal microbiota, affect susceptibility to sexually transmitted infections (STIs), and may impact local inflammation and patient symptoms. Examining the vaginal metabolome in the context of CT mono (CT+) and CT/MG co-infection (CT+/MG+) may identify biomarkers for infection or provide new insights into disease etiology and pathogenesis. Yet, the vaginal metabolome in the setting of CT infection is understudied and the composition of the vaginal metabolome in CT/MG co-infected women is unknown. Therefore, in this analysis, we used an untargeted metabolomic approach combined with 16S rRNA gene amplicon sequencing to characterize the vaginal microbiota and metabolomes of CT+, CT+/MG+, and uninfected women. We found that CT+ and CT+/MG+ women had distinct vaginal metabolomic profiles as compared to uninfected women both before and after adjustment for the vaginal microbiota. This study provides important foundational data documenting differences in the vaginal metabolome between CT+, CT+/MG+ and uninfected women. These data may guide future mechanistic studies that seek to provide insight into the pathogenesis of CT and CT/MG infections.

Carbohydrate (CHO) ingestion is an established strategy to improve endurance performance. Race fuels should not only sustain performance but also be readily digested and absorbed. Potatoes are a whole-food-based option that fulfills these criteria, yet their impact on performance remains unexamined. We investigated the effects of potato purée ingestion during prolonged cycling on subsequent performance vs. commercial CHO gel or a water-only condition. Twelve cyclists (70.7 ± 7.7 kg, 173 ± 8 cm, 31 ± 9 yr, 22 ± 5.1% body fat; means ± SD) with average peak oxygen consumption (V̇o2peak) of 60.7 ± 9.0 mL·kg−1·min−1 performed a 2-h cycling challenge (60–85% V̇o2peak) followed by a time trial (TT; 6 kJ/kg body mass) while consuming potato, gel, or water in a randomized-crossover design. The race fuels were administered with [U-13C6]glucose for an indirect estimate of gastric emptying rate. Blood samples were collected throughout the trials. Blood glucose concentrations were higher ( P < 0.001) in potato and gel conditions compared with water condition. Blood lactate concentrations were higher ( P = 0.001) after the TT completion in both CHO conditions compared with water condition. TT performance was improved ( P = 0.032) in both potato (33.0 ± 4.5 min) and gel (33.0 ± 4.2 min) conditions compared with water condition (39.5 ± 7.9 min). Moreover, no difference was observed in TT performance between CHO conditions ( P = 1.00). In conclusion, potato and gel ingestion equally sustained blood glucose concentrations and TT performance. Our results support the effective use of potatoes to support race performance for trained cyclists. NEW & NOTEWORTHY The ingestion of concentrated carbohydrate gels during prolonged exercise has been shown to promote carbohydrate availability and improve exercise performance. Our study aim was to expand and diversify race fueling menus for athletes by providing an evidence-based whole-food alternative to the routine ingestion of gels during training and competition. Our work shows that russet potato ingestion during prolonged cycling is as effective as carbohydrate gels to support exercise performance in trained athletes.

This study aimed to evaluate pharmacokinetic profiles of morphine in goats following a single dose administered intravenously, intramuscularly, or subcutaneously at 0.1 mg/kg, 0.25 mg/kg, and 0.4 mg/kg. Study population included eight healthy adult goats in a randomized cross-over study. Serial plasma samples were collected and morphine was quantified using high-performance liquid chromatography/mass spectrometry. Data fit a two-compartment model following intravenous administration and a non-compartmental model following both intramuscular and subcutaneous administration. Plasma elimination half-life was 2.88 ± 1.13 h (0.1 mg/kg), 2.30 ± 0.49 h (0.25 mg/kg), and 2.67 ± 0.82 h (0.4 mg/kg) following IV morphine. Intramuscular Cmax values were 13.4 ± 2.77 ng/ml (0.1 mg/kg), 34 ± 11.50 ng/ml (0.25 mg/kg), and 68.9 ± 24.5 ng/ml (0.4 mg/kg). Intramuscular Tmax f(h) or IM dosing (in hrs) was 0.19 ± 0.14 (0.1 mg/kg), 0.24 ± 0.24 (0.25 mg/kg), and 0.21 ± 0.24 (0.4 mg/kg). Subcutaneous Cmax values were 9.88 ± 3.31 ng/ml (0.1 mg/kg), 28.5 ± 11.6 ng/ml (0.25 mg/kg), and 39.4 ± 14.3 ng/ml (0.4 mg/kg). Subcutaneous Tmax (h) values for SC dosing were 0.36 ± 0.21 (0.1 mg/kg), 0.31 ± 0.17 (0.25 mg/kg), and 0.4 ± 0.13 (0.4 mg/kg). Intramuscular bioavailability values were 153.77 ± 12.60% (0.4 mg/kg), 104.8 ± 25.12% (0.25 mg/kg), and 100.7 ± 29.57% (0.1 mg/kg). Subcutaneous bioavailability values were 130.58 ± 19.07% (0.4 mg/kg), 116.6 ± 27.03% (0.25 mg/kg), and 111.6 ± 23.24% (0.1 mg/kg). No adverse effects were observed. Assuming plasma concentration required to induce analgesia is 16 ± 9 ng/ml in goats, as demonstrated in humans, it is suggested to administer morphine intramuscularly at 0.4 mg/kg every 3-4 h or SC every 2-3 h. This is a speculative conclusion therefore further studies evaluating pharmacodynamics and plasma analgesic threshold in goats is recommended.

Leucine is regarded as an anabolic trigger for the mTORC1 pathway and the stimulation muscle protein synthesis rates. More recently, there has been an interest in underpinning the relevance of branched-chain amino acid (BCAA)-containing dipeptides and their intact absorption into circulation to regulate muscle anabolic responses. We investigated the effects of dileucine and leucine ingestion on postprandial muscle protein turnover. Ten healthy young men (age: 23 ± 3 yr) consumed either 2 g of leucine (LEU) or 2 g of dileucine (DILEU) in a randomized crossover design. The participants underwent repeated blood and muscle biopsy sampling during primed continuous infusions of l-[

OBJECTIVES: Dietary protein intake augments muscle protein synthesis rates during acute recovery from resistance exercise training (RET) and can help offset age-related loss in muscle mass. Skeletal muscle tissue contains a variety of different protein pools such as myofibrillar (contractile), mitochondrial (substrate oxidation), and collagen (structural support) proteins that have been reported to have different contraction and nutrient sensitivities in controlled laboratory studies. However, no study has investigated the impact of dietary protein intake on the synthesis of these specific muscle proteins fractions during RET in a free-living setting. Therefore, we investigated the effect of dietary protein intake on daily muscle protein synthesis rates (PS) within the myofibrillar (MyoPS), mitochondrial (MitoPS), and collagen (CPS) protein fractions throughout the early phase (0 – 3 wks) of RET in middle-aged adults. METHODS: Twenty middle-aged adults (47 ± 1 y, BMI 28 ± 1 kg/m(2), M = 12, F = 8) were stratified and randomized to consume either moderate (MOD; 1.06 ± 0.22 g/kg/d) or high (HI; 1.55 ± 0.25 g/kg/d) amounts of protein during a dietary counseling-controlled resistance training program. On day 0, participants ingested intermittent boluses of deuterated ((2)H) water followed by daily maintenance doses throughout the study period. Muscle biopsies were collected prior to and at weeks 1, 2, and 3 of the intervention to assess MyoPS, MitoPS, and CPS by LC/MS. RESULTS: MitoPS decreased at 0–3 wks when compared to 0–1 wks (P = 0.010, CI: −0.77 – −0.10%/d) regardless of group (HI: 0.64 ± 0.32%/d and MOD 0.86 ± 0.55%/d; P = 0.827). A similar decline was also observed for CPS (group P = 0.323; time P = 0.007). The MyoPS in the HI condition remained constant (0–1 wk: 0.81 ± 0.42%/d and 0–3 wks: 0.81 ± 0.72%/d, P = 1.0), but MOD decreased over time (0–1 wk: 1.35 ± 0.9%/d and 0–3 wks: 0.77 ± 0.43%/d, P = 0.023). CONCLUSIONS: Our results demonstrated that additional protein intake above moderate amounts does not meaningfully potentiate the stimulation of longer-term muscle protein synthetic responses within the myofibrillar, mitochondrial, or collagen protein fractions during the early stages of a RET in middle-aged adults. FUNDING SOURCES: Funded in part by the Beef Checkoff. AFS funded by CAPES Scholarship.

Although Staphylococcus aureus is a major cause of food poisoning, little is known about its response to growth on food. Utilizing a transcriptional profiling and metabolomics approach, we compared S. aureus grown on autoclaved chicken breast (ACB) to Luria broth agar. ACB cultures demonstrated increased expression of genes associated with protein synthesis, cofactors, secondary metabolites, nitrogen and nucleotide metabolism, amino acid transport, and reduced expression of general stress, lipid metabolism, and virulence genes. The ACB culture also displayed characteristics of catabolite de-repression and anaerobic growth, and increased expression of arginine biosynthesis genes (argFGH) and an arginine/ornithine antiporter gene (arcD). S. aureus synthesizes arginine from proline and the ACB culture exhibited increased expression of proline transport genes (opuBA, opuBB and putP) and increased proline accumulation. Amino acid and sugar content in the ACB grown culture increased, and this was attributed to the consumption of ACB, transport of amino acids, and gluconeogenesis. Genes involved with biotin biosynthesis and uptake were upregulated and biotin is required for amino acid catabolism. Genes encoding urease and urease activity were upregulated in ACB cultures, while urea levels were reduced. This research provides fundamental information on the response of S. aureus growing on chicken meat that could find application in future attempts to reduce the growth of S. aureus in food.

Introduction Skeletal muscle loss is common in patients with renal failure who receive maintenance hemodialysis (MHD) therapy. Regular ingestion of protein-rich meals are recommended to help offset muscle protein loss in MHD patients, but little is known about the anabolic potential of this strategy. Methods Eight MHD patients (age: 56 ± 5 years; body mass index [BMI]: 32 ± 2 kg/m2) and 8 nonuremic control subjects (age: 50 ± 2 years: BMI: 31 ± 1 kg/m2) received primed continuous L-[ring-2H5]phenylalanine and L-[1-13C]leucine infusions with blood and muscle biopsy sampling on a nondialysis day. Participants consumed a mixed meal (546 kcal; 20-g protein, 59-g carbohydrates, 26-g fat) with protein provided as L-[5,5,5-2H3]leucine-labeled eggs. Results Circulating dietary amino acid availability was reduced in MHD patients (41 ± 5%) versus control subjects (61 ± 4%; P = 0.03). Basal muscle caspase-3 protein content was elevated (P = 0.03) and large neutral amino acid transporter 1 (LAT1) protein content was reduced (P = 0.02) in MHD patients versus control subjects. Basal muscle protein synthesis (MPS) was ∼2-fold higher in MHD patients (0.030 ± 0.005%/h) versus control subjects (0.014 ± 0.003%/h) (P = 0.01). Meal ingestion failed to increase MPS in MHD patients (absolute change from basal: 0.0003 ± 0.007%/h), but stimulated MPS in control subjects (0.009 ± 0.002%/h; P = 0.004). Conclusions MHD patients demonstrated muscle anabolic resistance to meal ingestion. This blunted postprandial MPS response in MHD patients might be related to high basal MPS, which results in a stimulatory ceiling effect and/or reduced plasma dietary amino acid availability after mixed-meal ingestion.

Bacterial vaginosis (BV) is the most common vaginal disorder of reproductive-aged women, yet its etiology remains enigmatic. One clinical symptom of BV, malodor, is linked to the microbial production of biogenic amines (BA). Using targeted liquid chromatography mass spectrometry, we analyzed 149 longitudinally collected vaginal samples to determine the in vivo concentrations of the most common BAs and then assessed their relationship to BV and effect upon the growth kinetics of axenically cultured vaginal Lactobacillus species. Increases in cadaverine, putrescine, and tyramine were associated with greater odds of women transitioning from L. crispatus-dominated vaginal microbiota to microbiota that have a paucity of Lactobacillus spp. and from Nugent scores of 0 to 3 to Nugent scores of 7 to 10, consistent with BV. Exposure to putrescine lengthened the lag time and/or slowed the growth of all vaginal Lactobacillus spp. except L. jensenii 62G. L. iners AB107’s lag time was lengthened by cadaverine but reduced in the presence of spermidine and spermine. The growth rate of L. crispatus VPI 3199 was slowed by cadaverine and tyramine, and strain-specific responses to spermine and spermidine were observed. BAs were associated with reduced production of d- and l-lactic acid by vaginal Lactobacillus spp., and this effect was independent of their effect upon Lactobacillus species growth. The exceptions were higher levels of d- and l-lactic acid by two strains of L. crispatus when grown in the presence of spermine. Results of this study provide evidence of a direct impact of common biogenic amines on vaginal Lactobacillus spp. IMPORTANCELactobacillus spp. are credited with providing the primary defense against gynecological conditions, including BV, most notably through the acidification of the vaginal microenvironment, which results from their production of lactic acid. The microbial production of BAs has been hypothesized to play a mechanistic role in diminishing Lactobacillus species-mediated protection, enabling the colonization and outgrowth of diverse anaerobic bacterial species associated with BV. Here, we demonstrate that in vivo increases in the most commonly observed BAs are associated with a loss of Lactobacillus spp. and the development of BV, measured by Nugent score. Further, we show that BAs formed by amino acid decarboxylase enzymes negatively affect the growth of type strains of the most common vaginal Lactobacillus spp. and separately alter their production of lactic acid. These results suggest that BAs destabilize vaginal Lactobacillus spp. and play an important and direct role in diminishing their protection of the vaginal microenvironment.

The results of this study indicate a discordance between gut microbiome composition and evolutionary history in primates, calling into question previous notions about host genetic control of the primate gut microbiome. Microbiome similarities between humans consuming nonindustrialized diets and monkeys characterized by subsisting on eclectic, omnivorous diets also raise questions about the ecological and nutritional drivers shaping the human gut microbiome. Moreover, a more detailed understanding of the factors associated with gut microbiome plasticity in primates offers a framework to understand why humans following industrialized lifestyles have deviated from states thought to reflect human evolutionary history. The results also provide perspectives for developing therapeutic dietary manipulations that can reset configurations of the gut microbiome to potentially improve human health., The gut microbiome of primates, including humans, is reported to closely follow host evolutionary history, with gut microbiome composition being specific to the genetic background of its primate host. However, the comparative models used to date have mainly included a limited set of closely related primates. To further understand the forces that shape the primate gut microbiome, with reference to human populations, we expanded the comparative analysis of variation among gut microbiome compositions and their primate hosts, including 9 different primate species and 4 human groups characterized by a diverse set of subsistence patterns (n = 448 samples). The results show that the taxonomic composition of the human gut microbiome, at the genus level, exhibits increased compositional plasticity. Specifically, we show unexpected similarities between African Old World monkeys that rely on eclectic foraging and human populations engaging in nonindustrial subsistence patterns; these similarities transcend host phylogenetic constraints. Thus, instead of following evolutionary trends that would make their microbiomes more similar to that of conspecifics or more phylogenetically similar apes, gut microbiome composition in humans from nonindustrial populations resembles that of generalist cercopithecine monkeys. We also document that wild cercopithecine monkeys with eclectic diets and humans following nonindustrial subsistence patterns harbor high gut microbiome diversity that is not only higher than that seen in humans engaging in industrialized lifestyles but also higher compared to wild primates that typically consume fiber-rich diets. IMPORTANCE The results of this study indicate a discordance between gut microbiome composition and evolutionary history in primates, calling into question previous notions about host genetic control of the primate gut microbiome. Microbiome similarities between humans consuming nonindustrialized diets and monkeys characterized by subsisting on eclectic, omnivorous diets also raise questions about the ecological and nutritional drivers shaping the human gut microbiome. Moreover, a more detailed understanding of the factors associated with gut microbiome plasticity in primates offers a framework to understand why humans following industrialized lifestyles have deviated from states thought to reflect human evolutionary history. The results also provide perspectives for developing therapeutic dietary manipulations that can reset configurations of the gut microbiome to potentially improve human health.

KEY POINTS Lifestyle modifications that include the regular performance of exercise are probably important for counteracting the negative consequences of obesity on postprandial myofibrillar protein synthetic responses to protein dense food ingestion. We show that the interactive effect of resistance exercise and feeding on the stimulation of myofibrillar protein synthesis rates is diminished with obesity compared to normal weight adults. The blunted myofibrillar protein synthetic response with resistance exercise in people with obesity may be underpinned by alterations in muscle anabolic signalling phosphorylation (p70S6K and 4E-BP1). The results obtained in the present study suggest that further exercise prescription manipulation may be necessary to optimize post-exercise myofibrillar protein synthesis rates in adults with obesity. ABSTRACT We aimed to determine whether obesity alters muscle anabolic and inflammatory signalling phosphorylation and also muscle protein synthesis within the myofibrillar (MYO) and sarcoplasmic (SARC) protein fractions after resistance exercise. Nine normal weight (NW) (21 ± 1 years, body mass index 22 ± 1 kg m-2 ) and nine obese (OB) (22 ± 1 years, body mass index 36 ± 2 kg m-2 ) adults received l-[ring-13 C6 ]phenylalanine infusions with blood and muscle sampling at basal and fed-state of the exercise (EX) and non-exercise (CON) legs. Participants performed unilateral leg extensions and consumed pork (36 g of protein) immediately after exercise. Basal muscle Toll-like receptor 4 (TLR4) protein was similar between OB and NW groups (P > 0.05) but increased at 300 min after pork ingestion only in the OB group (P = 0.03). Resistance exercise reduced TLR4 protein in the OB group at 300 min (EX vs. CON leg in OB: P = 0.04). Pork ingestion increased p70S6K phosphorylation at 300 min in CON and EX of the OB and NW groups (P > 0.05), although the response was lower in the EX leg of OB vs. NW at 300 min (P = 0.05). Basal MYO was similar between the NW and OB groups (P > 0.05) and was stimulated by pork ingestion in the EX and CON legs in both groups (Δ from basal NW: CON 0.04 ± 0.01% h-1 ; EX 0.10 ± 0.02% h-1 ; OB: CON 0.06 ± 0.01% h-1 ; EX 0.06 ± 0.01% h-1 ; P < 0.05). MYO was more strongly stimulated in the EX vs. CON legs in NW (P = 0.02) but not OB (P = 0.26). SARC was feeding sensitive but not further potentiated by resistance exercise in both groups. Our results suggest that obesity may attenuate the effectiveness of resistance exercise to augment fed-state MYO.

During a traditional set configuration of resistance exercise (TRD), characterized by a continuous completion of repetitions, a decrease in power output tends to occur throughout a set of repetitions. Inclusion of intraset rest, otherwise known as a cluster set configuration (CLU), counteracts this power decline. However, the effect of a CLU configuration on postexercise myofibrillar protein synthesis rates (MPS) and anabolic signaling has not been investigated. PURPOSE We aimed to determine if any mechanistic differences exist between TRD and CLU signaling events associated with muscle anabolism. METHODS In randomized crossover trials, eight resistance-trained participants (23 ± 1 yr, 81 ± 4.7 kg, body fat: 18% ± 1.9%; 1 repetition maximum [1RM], 150 ± 9.1 kg) performed an acute bout of CLU (4 sets × (2 × 5) repetitions, 30-s intraset rest, 90-s interset rest) and TRD (4 sets × 10 repetitions, 120-s interset rest) barbell back squats at approximately 70% 1RM with total volume load equated during primed continuous L-[ring-C6]phenylalanine infusions. Blood and muscle biopsy samples were collected at rest and after exercise at 0, 2, and 5 h. RESULTS There was no difference in postexercise MPS between the CLU and TRD condition (P > 0.05) and no changes in phosphorylation of mTORC1 downstream targets (p70S6K and 4EBP1). Total and phosphorylated yes-associated protein on Ser127 transiently increased (P < 0.01) immediately after exercise (t = 0) in CLU (~2.1-fold) and TRD condition (~2.2-fold). CONCLUSIONS Our results show that CLU is a viable anabolic option by preserving power output with similar MPS stimulation when compared with the TRD condition in trained young adults.

Endurance exercise increases indices of small intestinal damage and leucine oxidation, which may attenuate dietary amino acid appearance and postprandial leucine balance during postexercise recovery. Therefore, the purpose of this study was to examine the effect of an acute bout of endurance exercise on postprandial leucine kinetics and net leucine balance.In a crossover design, seven trained young men (age = 25.6 ± 2.3 yr; V˙O2peak = 61.4 ± 2.9 mL·kg·min; mean ± SEM) received a primed constant infusion of L-[1-C]leucine before and after ingesting a mixed macronutrient meal containing 18 g whole egg protein intrinsically labeled with L-[5,5,5-H3]leucine, 17 g fat, and 60 g carbohydrate at rest and after 60 min of treadmill running at 70% V˙O2peak.Plasma intestinal fatty acid binding protein concentrations and leucine oxidation both increased (P0.01) to peaks that were ~2.5-fold above baseline values during exercise with a concomitant decrease (P0.01) in nonoxidative leucine disposal. Meal ingestion attenuated (P0.01) endogenous leucine rates of appearance at rest and after exercise. There were no differences (both, P0.05) in dietary leucine appearance rates or in the amount of dietary protein-derived leucine that appeared into circulation over the 5-h postprandial period at rest and after exercise (62% ± 2% and 63% ± 2%, respectively). Leucine balance over the 5-h postprandial period was positive (P0.01) in both conditions but was negative (P0.01) during the exercise trial after accounting for exercise-induced leucine oxidation.We demonstrate that endurance exercise does not modulate dietary leucine availability from a mixed meal but attenuates postprandial whole-body leucine balance in trained young men.

Background: Protein in the diet is commonly ingested from whole foods that contain various macro- and micronutrients. However, the effect of consuming protein within its natural whole-food matrix on postprandial protein metabolism remains understudied in humans.Objective: We aimed to compare the whole-body and muscle protein metabolic responses after the consumption of whole eggs with egg whites during exercise recovery in young men.Design: In crossover trials, 10 resistance-trained men [aged 21 ± 1 y; 88 ± 3 kg; body fat: 16% ± 1% (means ± SEMs)] received primed continuous l-[ring-2H5]phenylalanine and l-[1-13C]leucine infusions and performed a single bout of resistance exercise. After exercise, participants consumed intrinsically l-[5,5,5-2H3]leucine-labeled whole eggs (18 g protein, 17 g fat) or egg whites (18 g protein, 0 g fat). Repeated blood and muscle biopsy samples were collected to assess whole-body leucine kinetics, intramuscular signaling, and myofibrillar protein synthesis.Results: Plasma appearance rates of protein-derived leucine were more rapid after the consumption of egg whites than after whole eggs (P = 0.01). Total plasma availability of leucine over the 300-min postprandial period was similar (P= 0.75) between the ingestion of whole eggs (68% ± 1%) and egg whites (66% ± 2%), with no difference in whole-body net leucine balance (P = 0.27). Both whole-egg and egg white conditions increased the phosphorylation of mammalian target of rapamycin complex 1, ribosomal protein S6 kinase 1, and eukaryotic translation initiation factor 4E-binding protein 1 during postexercise recovery (all P < 0.05). However, whole-egg ingestion increased the postexercise myofibrillar protein synthetic response to a greater extent than did the ingestion of egg whites (P= 0.04).Conclusions: We show that the ingestion of whole eggs immediately after resistance exercise resulted in greater stimulation of myofibrillar protein synthesis than did the ingestion of egg whites, despite being matched for protein content in young men. Our data indicate that the ingestion of nutrient- and protein-dense foods differentially stimulates muscle anabolism compared with protein-dense foods. This trial was registered at clinicaltrials.gov as NCT03117127.

Bigheaded Carp have spread throughout the Mississippi River basin since the 1970s. Little has stopped the spread as carp have the ability to pass through locks and dams, and they are currently approaching the Great Lakes. However, the location of the leading edge in the Illinois River has stalled for over a decade, even though there is no barrier preventing further advancement towards the Great Lakes. Defining why carp are not moving towards the Great Lakes is important for predicting why they might advance in the future. The aim of this study was to test the hypothesis that anthropogenic contaminants in the Illinois River may be playing a role in preventing further upstream movement of Bigheaded Carp. Ninety three livers were collected from carp at several locations between May and October of 2018. Liver samples were analyzed using gas chromatography-mass spectrometry in a targeted metabolite profiling approach. Livers from carp at the leading edge had differences in energy use and metabolism, and suppression of protective mechanisms relative to downstream fish; differences were consistent across time. This body of work provides evidence that water quality is linked to carp movement in the Illinois River. As water quality in this region continues to improve, consideration of this impact on carp spread is essential to protect the Great Lakes.

OBJECTIVES: The ingestion of free amino acids, or isolated sources of protein, results in faster postprandial release of dietary amino acids into circulation, which stimulates muscle protein synthesis rates. However, indirect evidence suggests that this rapid release of dietary amino acids after the ingestion of free amino acids is coupled with higher amino acid oxidation rates when compared to a whole-food source. Whole food protein results in a reduced peak amplitude and prolonged postprandial aminoacidemia. This study aimed to assess the effects of eating a whole food source of protein on the stimulation of whole-body leucine oxidation rates versus eating these same nutrients in isolated form in healthy young adults. METHODS: In a crossover design, 10 recreationally active adults (24 ± 4 y; 5 M, 5 F) performed an acute bout of resistance exercise followed by the ingestion of salmon (SAL) (20.5 g protein and 7.5 g fat) or its matched constituents as crystalline amino acids and fish oil (ISO). Participants received priming doses of NaH(13)CO(2) and L-[1–(13)C]leucine before initiating a constant L-[1–(13)C]leucine infusion. Blood and breath samples were collected at rest and after resistance exercise at regular intervals for the measurement of whole-body leucine oxidation rates and plasma leucine profiles. Data were tested using linear fixed effects models with time and group as fixed factors with Bonferroni's post hoc test. RESULTS: Postprandial plasma leucine concentrations did not differ between the SAL and ISO conditions (P > 0.05). Time to peak plasma leucine concentrations was faster in ISO (50 ± 27 min) vs. SAL (114 ± 64 min, P = 0.022) condition. Postprandial leucine oxidation rates were elevated from baseline at t = 30 min to t = 120 min in ISO and t = 60 min to t = 180 min in SAL (P

Excess fat mass may diminish the anabolic potency of protein-rich food ingestion to stimulate muscle protein subfractional synthetic responses. However, the impact of adiposity on mitochondrial protein synthesis (MPS) rates after protein-rich food ingestion has not been thoroughly examined in vivo in humans.We compared basal and postprandial MPS and markers of muscle inflammation [toll-like receptor 4 (TLR4) and myeloid differentiation primary response protein 88 (MyD88) protein content] in young adults with different body mass indices (BMIs).Ten normal-weight (NW; BMI = 22.7 ± 0.4 kg/m2), 10 overweight (OW; BMI = 27.1 ± 0.5 kg/m2), and 10 obese (OB; BMI = 35.9 ± 1.3 kg/m2) adults received primed continuous L-[ring-13C6]phenylalanine infusions, blood sampling, and skeletal muscle biopsies before and after the ingestion of 170 g of pork.Pork ingestion increased muscle TLR4 and MyD88 protein content in the OB group (P0.05), but not in the NW or OW groups. Basal MPS was similar between groups (P0.05). Pork ingestion stimulated MPS (P0.001; 0 to 300 minutes) in the NW (2.5- ± 0.6-fold above baseline values), OW (1.7- ± 0.3-fold), and OB groups (2.4- ± 0.5-fold) with no group differences (P0.05).Protein-dense food ingestion promotes muscle inflammatory signaling only in OB adults. However, the consumption of a dinner-sized amount of protein strongly stimulated a postprandial MPS response irrespective of BMI. Our data suggest that alterations in postprandial MPS are unlikely to contribute to compromised muscle macronutrient metabolism witnessed with obesity.

BACKGROUND: We have recently shown that a novel signalling kinase, inositol hexakisphosphate kinase 1 (IP6K1), is implicated in whole-body insulin resistance via its inhibitory action on Akt. Insulin and insulin like growth factor 1 (IGF-1) share many intracellular processes with both known to play a key role in glucose and protein metabolism in skeletal muscle. AIMS: We aimed to compare IGF/IP6K1/Akt signalling and the plasma proteomic signature in individuals with a range of BMIs after ingestion of lean meat. METHODS: Ten lean [Body mass index (BMI) (in kg/m(2)): 22.7 ± 0.4; Homeostatic model assessment of insulin resistance (HOMA(IR)): 1.36 ± 0.17], 10 overweight (BMI: 27.1 ± 0.5; HOMA(IR): 1.25 ± 0.11), and 10 obese (BMI: 35.9 ± 1.3; HOMA(IR): 5.82 ± 0.81) adults received primed continuous L-[ring-(13)C(6)]phenylalanine infusions. Blood and muscle biopsy samples were collected at 0 min (post-absorptive), 120 min and 300 min relative to the ingestion of 170 g pork loin (36 g protein and 5 g fat) to examine skeletal muscle protein signalling, plasma proteomic signatures, and whole-body phenylalanine disappearance rates (R(d)). RESULTS: Phenylalanine R(d) was not different in obese compared to lean individuals at all time points and was not responsive to a pork ingestion (basal, P = 0.056; 120 & 300min, P > 0.05). IP6K1 was elevated in obese individuals at 120 min post-prandial vs basal (P < 0.05). There were no acute differences plasma proteomic profiles between groups in the post-prandial state (P > 0.05). CONCLUSIONS: These data demonstrate, for the first time that muscle IP6K1 protein content is elevated after lean meat ingestion in obese adults, suggesting that IP6K1 may be contributing to the dysregulation of nutrient uptake in skeletal muscle. In addition, proteomic analysis showed no differences in proteomic signatures between obese, overweight or lean individuals.

OBJECTIVES: High protein diets (>1.6 g/kg/d) are thought to maximize daily myofibrillar protein synthesis (MPS) rates to resistance exercise training. Current research has focused on isolated protein sources to stimulate MPS disregarding other nutritional factors within a healthy diet. Therefore, we examined the impact of dietary counseling underlining food-focused healthy eating patterns equally distributing protein through high-quality sources at the Recommended Daily Allowance (RDA) or in excess on resistance exercise mediated daily rates of MPS in middle-aged adults. METHODS: Nineteen healthy middle-aged adults (11 M, 8F, 48 ± 7 y, BMI: 28.9 ± 3.7 kg/m(2), 7451 ± 4957 steps/d) were randomized to consume protein at the RDA (0.8–1.0 g/kg/d, n = 10) or twice the RDA (2 × RDA, 1.6–1.8 g/kg/d, n = 9) for 2 weeks. Participants were counseled to equally distribute protein between meals and consumed either 15 g (RDA) or 30 g (2 × RDA) protein from lean beef in immediately post-exercise and nightly. Week 0 (−7 to 0 d) served as a dietary habituation, and week 1 (1–8 d) included whole body resistance exercise sessions (3/wk) with the dietary intervention. On 0 d, participants ingested 5 mL/kg over 10.5 h of deuterated water ((2)H(2)O) for deuterium enrichment of body water, with maintenance daily doses of 0.625 mL/kg/d (2)H(2)O for days 1–8. Repeated saliva and muscle biopsies from the vastus lateralis were collected throughout the 1-week intervention to assess daily rates of MPS. RESULTS: The 2 × RDA group (1.6 ± 0.4 g/kg/d) consumed significantly more protein than the RDA group (1.0 ± 0.4 g/kg/d, P = 0.01). Steady-state body water enrichment was not different (P = 0.94) between the 2 × RDA (0.9 ± 0.3%) or RDA (0.9 ± 0.1%) groups. Daily MPS was not different (P = 0.43) between RDA (0.91 ± 0.2%/d) and 2 × RDA groups (1.13 ± 0.6%/d) during the 1-week intervention. CONCLUSIONS: Daily MPS with resistance exercise training is not altered by a more protein-dense diet when at least the RDA is consumed in middle-aged adults. Our data suggest that multi-component nutritional strategies focusing on protein quality, distribution, and timing may supersede the importance of only considering total quantity to support early hypertrophic protein remodeling with resistance exercise. FUNDING SOURCES: This work was supported by funds provided by the National Cattleman's Beef Association.

Sanitary pads and diapers are made of synthetic plastic materials that can potentially be released while being used. This study measured the amounts of volatile organic compounds (VOCs) (methylene chloride, toluene, and xylene) and phthalates (DBP, DEHP, DEP, and BBP) contained in sanitary pads and diapers. In sanitary pads, 5,900- and 130-fold differences of VOC and phthalate concentrations were seen among the brands. In the diapers, 3- and 63-fold differences of VOC and phthalate concentrations were detected among the brands. VOC concentrations from the sanitary pads and diapers were similar to that of the residential air. However, phthalate concentrations of sanitary pads and diapers were significantly higher than those found in common commercial plastic products. As sanitary pads and diapers are in direct contact with external genitalia for an extended period, there is a probability that a considerable amount of VOCs or phthalates could be absorbed into the reproductive system.

BACKGROUND Excess body fat diminishes muscle protein synthesis rates in response to hyperinsulinemic-hyperaminoacidemic clamps. However, muscle protein synthetic responses after the ingestion of a protein-dense food source across a range of body mass indexes (BMIs) have not been compared. OBJECTIVE We compared the myofibrillar protein synthetic response and underlying nutrient-sensing mechanisms after the ingestion of lean pork between obese, overweight, and healthy-weight adults. DESIGN Ten healthy-weight [HW; BMI (in kg/m2): 22.7 ± 0.4], 10 overweight (OW; BMI: 27.1 ± 0.5), and 10 obese (OB; BMI: 35.9 ± 1.3) adults received primed continuous l-[ring-13C6]phenylalanine infusions. Blood and muscle biopsy samples were collected before and after the ingestion of 170 g pork (36 g protein and 3 g fat) to assess skeletal muscle anabolic signaling, amino acid transporters [large neutral and small neutral amino acid transporters (LAT1, SNAT2) and CD98], and myofibrillar protein synthesis. RESULTS At baseline, OW and OB groups showed greater relative amounts of mammalian target of rapamycin complex 1 (mTORC1) protein than the HW group. Pork ingestion increased mTORC1 phosphorylation only in the HW group (P = 0.001). LAT1 and SNAT2 protein content increased during the postprandial period in all groups (time effect, P < 0.05). Basal myofibrillar protein synthetic responses were similar between groups (P = 0.43). However, myofibrillar protein synthetic responses (0-300 min) were greater in the HW group (1.6-fold; P = 0.005) after pork ingestion than in the OW and OB groups. CONCLUSIONS There is a diminished myofibrillar protein synthetic response to the ingestion of protein-dense food in overweight and obese adults compared with healthy-weight controls. These data indicate that impaired postprandial myofibrillar protein synthetic response may be an early defect with increasing fat mass, potentially dependent on altered anabolic signals, that reduces muscle sensitivity to food ingestion. This trial was registered at clinicaltrials.gov as NCT02613767.

We examined 185 metabolites in 30 adult Humboldt Penguins (Spheniscus humboldti) nesting at the Punta San Juan Marine Protected Area, Peru, in order to examine gender differences in metabolome profiles, particularly those involved in metabolism and energetics. The majority of the compounds identified were fatty (26% of total identified compounds), organic (19%), and amino (16%) acids. We were able to differentiate male and female penguins with 96.6% accuracy on the basis of 12 metabolites, most of which are involved in lipid and carbohydrate metabolism. These included 2-oxoglutarate, erythronic acid, GABA, mannitol, sedoheptulose 7-phosphate, and serine and six metabolites present in higher concentrations in females compared to males (2-aminoadipic acid, O-phosphorylethanolamine, glycerol 2-phosphate, glycerol 3-phosphate, pantothenic acid, and creatinine). Of these, 2-oxoglutarate and glycerol 3-phosphate were key metabolites distinguishing gender. Our results indicated that male and female Humboldt Penguins were characterized by differing metabolic states. Such differences could be important to individual and brood survival in times of environmental stress.

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) has evolved to become an effective discovery tool in science and clinical diagnostics. Here, chemical imaging approaches are applied to well-defined regions of the mammalian peripheral sensory-motor system, including the dorsal root ganglia (DRG) and adjacent nerves. By combining several MSI approaches, analyte coverage is increased and 195 distinct molecular features are observed. Principal component analysis suggests three chemically different regions within the sensory-motor system, with the DRG and adjacent nerve regions being the most distinct. Investigation of these regions using gas chromatography-mass spectrometry corroborate these findings and reveal important metabolic markers related to the observed differences. The heterogeneity of the structurally, physiologically, and functionally connected regions demonstrates the intricate chemical and spatial regulation of their chemical composition.

Complete genome comparisons, transcriptomic and metabolomic studies were performed on two laboratory-selected, well-characterized vancomycin-intermediate Staphylococcus aureus (VISA) derived from the same parent MRSA that have changes in cell wall composition and decreased autolysis. A variety of mutations were found in the VISA, with more in strain 13136p−m+V20 (vancomycin MIC = 16 µg/mL) than strain 13136p−m+V5 (MIC = 8 µg/mL). Most of the mutations have not previously been associated with the VISA phenotype, some were associated with cell wall metabolism and many with stress responses, notably relating to DNA damage. The genomes and transcriptomes of the two VISA support the importance of gene expression regulation to the VISA phenotype. Similarities in overall transcriptomic and metabolomic data indicated that the VISA physiologic state includes elements of the stringent response, such as downregulation of protein and nucleotide synthesis, the pentose phosphate pathway and nutrient transport systems. Gene expression for secreted virulence determinants was generally downregulated, but was more variable for surface-associated virulence determinants, although capsule formation was clearly inhibited. The importance of activated stress response elements could be seen across all three analyses, as in the accumulation of osmoprotectant metabolites such as proline and glutamate. Concentrations of potential cell wall precursor amino acids and glucosamine were increased in the VISA strains. Polyamines were decreased in the VISA, which may facilitate the accrual of mutations. Overall, the studies confirm the wide variability in mutations and gene expression patterns that can lead to the VISA phenotype.

Red rice (Oryza sativa L.) that has a red (reddish brown) bran layer in de-hulled rice is known to contain rich biofunctional components. Germination is an effective technique to improve the nutritional quality, digestibility, and flavor of de-hulled rice. Ultrasonication, a form of physical stimulation, has been documented as a novel approach to improve the nutritional quality of plant-based food. This study was undertaken to test the use of ultrasound to enhance the nutritional value of red rice. Ultrasonication (5min, 16W/L) was applied to rice during soaking or after 66h germination. Changes of metabolites (amino acids, sugars, and organic acids) in red rice treated by ultrasonication were determined using a GC/MS plant primary metabolomics analysis platform. Differential expressed metabolites were identified through multivariate statistical analysis. Results showed that γ-aminobutyric acid (GABA) and riboflavin (vitamin B2) in red rice significantly increased after germination for 72h, and then experienced a further increase after treatment by ultrasound at different stages during germination. The metabolomics analysis showed that some plant metabolites, i.e. GABA, O-phosphoethanolamine, and glucose-6-phosphate were significantly increased after the ultrasonic treatment (VIP>1.5) in comparison with the untreated germinated rice. The findings of this study showed that controlled germination with ultrasonic stress is an effective method to enhance GABA and other health-promoted components in de-hulled rice.

Although soybean seeds appear homogeneous, their composition (protein, oil and mineral concentrations) can vary significantly with the canopy position where they were produced. In studies with 10 cultivars grown over a 3-yr period, we found that seeds produced at the top of the canopy have higher concentrations of protein but less oil and lower concentrations of minerals such as Mg, Fe, and Cu compared to seeds produced at the bottom of the canopy. Among cultivars, mean protein concentration (average of different positions) correlated positively with mean concentrations of S, Zn and Fe, but not other minerals. Therefore, on a whole plant basis, the uptake and allocation of S, Zn and Fe to seeds correlated with the production and allocation of reduced N to seed protein; however, the reduced N and correlated minerals (S, Zn and Fe) showed different patterns of allocation among node positions. For example, while mean concentrations of protein and Fe correlated positively, the two parameters correlated negatively in terms of variation with canopy position. Altering the microenvironment within the soybean canopy by removing neighboring plants at flowering increased protein concentration in particular at lower node positions and thus altered the node-position gradient in protein (and oil) without altering the distribution of Mg, Fe and Cu, suggesting different underlying control mechanisms. Metabolomic analysis of developing seeds at different positions in the canopy suggests that availability of free asparagine may be a positive determinant of storage protein accumulation in seeds and may explain the increased protein accumulation in seeds produced at the top of the canopy. Our results establish node-position variation in seed constituents and provide a new experimental system to identify genes controlling key aspects of seed composition. In addition, our results provide an unexpected and simple approach to link agronomic practices to improve human nutrition and health in developing countries because food products produced from seeds at the bottom of the canopy contained higher Fe concentrations than products from the top of the canopy. Therefore, using seeds produced in the lower canopy for production of iron-rich soy foods for human consumption could be important when plants are the major source of protein and human diets can be chronically deficient in Fe and other minerals.

Background With the increasing interest in metabolic engineering of plants using genetic manipulation and gene editing technologies to enhance growth, nutritional value and environmental adaptation, a major concern is the potential of undesirable broad and distant effects of manipulating the target gene or metabolic step in the resulting plant. A comprehensive transcriptomic and metabolomic analysis of the product may shed some useful light in this regard. The present study used these two techniques with plant cell cultures to analyze the effects of genetic manipulation of a single step in the biosynthesis of polyamines because of their well-known roles in plant growth, development and stress responses. Results The transcriptomes and metabolomes of a control and a high putrescine (HP) producing cell line of poplar (Populus nigra x maximowiczii) were compared using microarrays and GC/MS. The HP cells expressed an ornithine decarboxylase transgene and accumulated several-fold higher concentrations of putrescine, with only small changes in spermidine and spermine. The results show that up-regulation of a single step in the polyamine biosynthetic pathway (i.e. ornithine → putrescine) altered the expression of a broad spectrum of genes; many of which were involved in transcription, translation, membrane transport, osmoregulation, shock/stress/wounding, and cell wall metabolism. More than half of the 200 detected metabolites were significantly altered (p ≤ 0.05) in the HP cells irrespective of sampling date. The most noteworthy differences were in organic acids, carbohydrates and nitrogen-containing metabolites. Conclusions The results provide valuable information about the role of polyamines in regulating nitrogen and carbon use pathways in cell cultures of high putrescine producing transgenic cells of poplar vs. their low putrescine counterparts. The results underscore the complexity of cellular responses to genetic perturbation of a single metabolic step related to nitrogen metabolism in plants. Combined with recent studies from our lab, where we showed that higher putrescine production caused an increased flux of glutamate into ornithine concurrent with enhancement in glutamate production via additional nitrogen and carbon assimilation, the results from this study provide guidance in designing transgenic plants with increased nitrogen use efficiency, especially in plants intended for non-food/feed applications (e.g. increased biomass production for biofuels). Electronic supplementary material The online version of this article (doi:10.1186/s12870-016-0796-2) contains supplementary material, which is available to authorized users.

The yeast N-acetyltransferase MPR1 gene has previously been shown to confer resistance to the toxic proline analogue azetidine-2-carboxylic acid (A2C) in yeast and transgenic tobacco. Here experiments were carried out to determine if MPR1 and A2C can work as a selectable marker system for plant transformation. The MPR1 gene was inserted into a binary vector under the control of the cauliflower mosaic virus 35S promoter and nopaline synthase terminator, and transformed into tobacco via the Agrobacterium tumefaciens-mediated leaf disc method. A2C was applied in the selection medium to select for putative transformants. PCR analysis showed that 28.4% and 66.7% of the plantlets selected by 250 muM and 300 muM A2C were positive for the MPR1 gene, respectively. Southern and northern blot analysis and enzyme activity assay confirmed the stable gene incorporation, transcription, and translation of the MPR1 transgene in the transgenic plants. The transgene-carrying T(1) progeny could be distinguished from the recessive progeny when grown on 400, 450, or 500 muM A2C. Examination of the metabolism of 22 transgenic plants by gas chromatography-mass spectrometry profiling did not reveal any significant changes. In conclusion, the results demonstrate that MPR1/A2C is a safe and efficient selection system that does not involve microbial antibiotic or herbicide resistance genes. Recent studies showed that MPR1 can protect yeast against oxidative stresses by decreasing the accumulation of the proline catabolite Delta(1)-pyrroline-5-carboxylate (P5C). However, H(2)O(2) treatment resulted in contradictory responses among the five transgenic lines tested. Further experiments are required to assess the response of MPR1 transgenic plants under oxidative stress.

The drought stress tolerance of two Solanum tuberosum subsp. andigena landraces, one hybrid (adgxtbr) and Atlantic (S. tuberosum subsp. tuberosum) has been evaluated. Photosynthesis in the Andigena landraces during prolonged drought was maintained significantly longer than in the Tuberosum (Atlantic) line. Among the Andigena landraces, 'Sullu' (SUL) was more drought resistant than 'Negra Ojosa' (NOJ). Microarray analysis and metabolite data from leaf samples taken at the point of maximum stress suggested higher mitochondrial metabolic activity in SUL than in NOJ. A greater induction of chloroplast-localized antioxidant and chaperone genes in SUL compared with NOJ was evident. ABA-responsive TFs were more induced in NOJ compared with SUL, including WRKY1, mediating a response in SA signalling that may give rise to increased ROS. NOJ may be experiencing higher ROS levels than SUL. Metabolite profiles of NOJ were characterized by compounds indicative of stress, for example, proline, trehalose, and GABA, which accumulated to a higher degree than in SUL. The differences between the Andigena lines were not explained by protective roles of compatible solutes; hexoses and complex sugars were similar in both landraces. Instead, lower levels of ROS accumulation, greater mitochondrial activity and active chloroplast defences contributed to a lower stress load in SUL than in NOJ during drought.

Soybean [Glycine max (L.) Merr.] embryogenic cultures were transformed by particle bombardment with the feedback-insensitive tobacco anthranilate synthase (AS) gene ASA2 driven by the CaMV 35S promoter and selected using hph as the selectable marker gene. Only one of eight regenerated lines that set seed and contained ASA2 expressed the gene highly and contained increased free tryptophan (Trp) levels in leaves, seeds and embryogenic cultures. Leaf extracts of the ASA2 expressing line contained about twice as much AS enzyme activity as the untransformed control and this activity was only slightly more feedback-insensitive. Amino acid analysis showed that both leaves and embryogenic tissue cultures of the ASA2 expressing line had four to five-times the normal levels of free Trp and slightly higher free tyrosine and phenylalanine. The seed total Trp content was only slightly increased. Metabolic profiling-analysis by GC-MS detected no other consistent differences. These studies show that the ASA2 gene can be expressed in soybean and that modest changes in Trp synthesis occurs.

Background Environmental factors such as temperature, nutrient availability, and larval density determine the outcome of postembryonic development in mosquitoes. Suboptimal temperatures, crowding, and starvation during the larval phase reduce adult mosquito size, nutrient stores and affect vectorial capacity. Methods In this study we compared adult female Aedes aegypti, Rockefeller strain, raised under standard laboratory conditions (Large) with those raised under crowded and nutritionally deprived conditions (Small). To compare the gene expression and nutritional state of the major energy storage and metabolic organ, the fat body, we performed transcriptomics using Illumina based RNA-seq and metabolomics using GC/MS on females before and 24 hours following blood feeding. Results Analysis of fat body gene expression between the experimental groups revealed a large number of significantly differentially expressed genes. Transcripts related to immunity, reproduction, autophagy, several metabolic pathways; including amino acid degradation and metabolism; and membrane transport were differentially expressed. Metabolite profiling identified 60 metabolites within the fat body to be significantly affected between small and large mosquitoes, with the majority of detected free amino acids at a higher level in small mosquitoes compared to large. Conclusions Gene expression and metabolites in the adult fat body reflect the individual post-embryonic developmental history of a mosquito larva. These changes affect nutritional storage and utilization, immunity, and reproduction. Therefore, it is apparent that changes in larval environment due to weather conditions, nutrition availability, vector control efforts, and other factors can affect adult vectorial capacity in the field. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-0863-9) contains supplementary material, which is available to authorized users.