Clinical Reasoning: Pediatric Seizures of Unknown Cause.

We describe a neonate and a 14-month-old child presenting with seizures that were not (completely) controlled with antiepileptic medications. There were no signs of infection, and electrolytes and neuroimaging were normal. In the neonate, pyridoxine was administered followed by cessation of seizures, and a diagnosis of pyridoxine-dependent epilepsy (PDE-ALDH7A1, a neurometabolic disorder of lysine metabolism) was genetically confirmed. The 14-month-old child received a genetic diagnosis of PDE-ALDH7A1 after abnormalities in the metabolic investigations. Both children were treated with pyridoxine and adjunct lysine reduction therapy (LRT). Seizures were controlled completely, but both children are developmentally delayed. During her second pregnancy, the mother of the neonate was started on pyridoxine treatment because of the risk of PDE-ALDH7A1. After delivery, pyridoxine treatment was continued in the neonate, who did not show any clinical symptoms. Molecular analysis identified the familial variants consistent with the diagnosis of PDE-ALDH7A1. Adjunct LRT was initiated. This child has never experienced seizures, and development has been completely normal thus far (age 2.9 years), despite the shared genotype with their sibling with developmental delays (DDs). In conclusion, in neonates, infants, and children presenting with seizures of unknown origin with partial or no response to common antiepileptic medications, the diagnosis of PDE-ALDH7A1 or other pyridoxine-responsive genetic epilepsies should be considered, prompting a trial of pyridoxine as "diagnostic therapeuticum." The digital application Treatable-ID (treatable-id.org) can support clinicians in the early diagnosis of treatable conditions in patients presenting with DD/intellectual disability of unknown cause.

Habitual intake of dietary advanced glycation end products is not associated with generalized microvascular function-the Maastricht Study.

BACKGROUND: Endogenously formed advanced glycation end products (AGEs) may be important drivers of microvascular dysfunction and the microvascular complications of diabetes. AGEs are also formed in food products, especially during preparation methods involving dry heat. OBJECTIVES: We aimed to assess cross-sectional associations between dietary AGE intake and generalized microvascular function in a population-based cohort. METHODS: In 3144 participants of the Maastricht Study (mean ± SD age: 60 ± 8 y, 51% men) the dietary AGEs Nε-(carboxymethyl)lysine (CML), Nε-(1-carboxyethyl)lysine (CEL), and Nδ-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1) were estimated using the combination of our ultra-performance LC-tandem MS dietary AGE database and an FFQ. Microvascular function was determined in the retina as flicker light-induced arteriolar and venular dilation and as central retinal arteriolar and venular equivalents, in plasma as a z score of endothelial dysfunction biomarkers (soluble vascular adhesion molecule 1 and soluble intracellular adhesion molecule 1, soluble E-selectin, and von Willebrand factor), in skin as the heat-induced skin hyperemic response, and in urine as 24-h albuminuria. Associations were evaluated using multiple linear regression adjusting for demographic, cardiovascular, lifestyle, and dietary factors. RESULTS: Overall, intakes of CML, CEL, and MG-H1 were not associated with the microvascular outcomes. Although higher intake of CEL was associated with higher flicker light-induced venular dilation (ß percentage change over baseline: 0.14; 95% CI: 0.02, 0.26) and lower plasma biomarker z score (ß: -0.04 SD; 95% CI: -0.08, -0.00 SD), the effect sizes were small and their biological relevance can be questioned. CONCLUSIONS: We did not show any strong association between habitual intake of dietary AGEs and generalized microvascular function. The contribution of dietary AGEs to generalized microvascular function should be further assessed in randomized controlled trials using specifically designed dietary interventions.

Exposure of Caenorhabditis elegans to Dietary Nε-Carboxymethyllysine Emphasizes Endocytosis as a New Route for Intestinal Absorption of Advanced Glycation End Products.

The impact of dietary advanced glycation end products (dAGEs) on human health has been discussed in many studies but, to date, no consensual pathophysiological process has been demonstrated. The intestinal absorption pathways which have so far been described for dAGEs, the passive diffusion of free AGE adducts and transport of glycated di-tripeptides by the peptide transporter 1 (PEPT-1), are not compatible with certain pathophysiological processes described. To get new insight into the intestinal absorption pathways and the pathophysiological mechanisms of dAGEs, we initiated an in vivo study with a so-called simple animal model with a complete digestive tract, Caenorhabditis elegans. Dietary bacteria were chemically modified with glyoxylic acid to mainly produce Nε-carboxymethyllysine (CML) and used to feed the worms. We performed different immunotechniques using an anti-CML antibody for the relative quantification of ingested CML and localization of this AGE in the worms' intestine. The relative expression of genes encoding different biological processes such as response to stresses and intestinal digestion were determined. The physiological development of the worms was verified. All the results were compared with those obtained with the control bacteria. The results revealed a new route for the intestinal absorption of dietary CML (dCML), endocytosis, which could be mediated by scavenger receptors. The exposure of worms to dCML induced a reproductive defect and a transcriptional response reflecting oxidative, carbonyl and protein folding stresses. These data, in particular the demonstration of endocytosis of dCML by enterocytes, open up new perspectives to better characterize the pathophysiological mechanisms of dAGEs.

The effect of ketoprofen lysine salt on mucosa of rat stomach after ethyl alcohol intoxication.

INTRODUCTION: Ketoprofen is a commonly used nonsteroidal anti-inflammatory drug (NSAID) with analgesic and antipyretic properties. Side effects of ketoprofen occur mainly from the gastrointestinal tract due to the inhibition of cyclooxygenaze-1. Binge drinking at least once a week is reported by 80 million Europeans. On the day after many of them use NSAIDs. This increases the risk for damage of gastric mucosa. AIM: The aim of the study was to check if use of ketoprofen lysine salt (KLS) has any gastroprotective effect on mucosa of rat stomach after ethyl alcohol intoxication. MATERIALS AND METHODS: There were 6 groups of 6 male rats which received: RESULTS: In groups 1, 2 and 3 the histopathologic examination of the stomachs revealed normal picture, without signs of inflammation. In the group 4, 5 and 6 within the mucosa and submucosa there were visible numerous infiltrates of inflammatory cells, consisting mainly of lymphocytes, plasmocytes and eosinophilia. Total leukocyte count was elevated in group 3, 4, 6. There was a significant decrease of blood urea concentration in group 6 vs 2 and significant decrease of serum albumin in group 6 vs 1 and 2, and total protein vs group 1. CONCLUSION: Side effects of ketoprofen occur mainly from the gastrointestinal tract. KLS has no gastroprotective effect after ethanol-gastric injury and does not protect gastric mucosa from damage produced by binge drinking. Therefore it should not be used after drinking distilled spirits.

Inhibition of inducible nitric oxide synthase protects against the deleterious effects of sub-lethal sepsis and ethanol in the cardiorenal system.

We tested the hypothesis that ethanol would aggravate the deleterious effects of sub-lethal cecal ligation and puncture (SL-CLP) sepsis in the cardiorenal system and that inhibition of inducible nitric oxide synthase (iNOS) would prevent such response. Male C57BL/6 mice were treated with ethanol for 12 weeks. One hour before SL-CLP surgery, mice were treated with N6-(1-iminoethyl)-lysine (L-NIL, 5 mg/kg, i.p.), a selective inhibitor of iNOS. A second dose of L-NIL was administered 24 h after SL-CLP surgery. Mice were killed 48 h post surgery and the blood, the renal cortex, and the left ventricle (LV) were collected for biochemical analysis. L-NIL attenuated the increase in serum creatinine levels induced by ethanol, but not by SL-CLP. Ethanol, but not SL-CLP, increased creatine kinase (CK)-MB activity and L-NIL did not prevent this response. In the renal cortex, L-NIL prevented the redox imbalance induced by ethanol and SL-CLP. Inhibition of iNOS also decreased lipoperoxidation induced by ethanol and SL-CLP in the LV. L-NIL prevented the increase of pro-inflammatory cytokines and reactive oxygen species induced by ethanol and (or) SL-CLP in the cardiorenal system, suggesting that iNOS modulated some of the molecular mechanisms that underlie the deleterious effects of both conditions in the cardiorenal system.

Oral aspirin or low dose of intravenous lysine acetylsalicylate in ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention.

AIM: To compare the pharmacodynamic effect of an oral loading dose of 'noncoated' ASA 300 mg vs. an intravenous bolus injection of lysine acetylsalicylate 150 mg in patients with STEMI undergoing pPCI. METHODS: This was a prospective single-center, open label, pharmacodynamic study, including nonconsecutive patients presenting at our catheterization laboratory with STEMI undergoing pPCI and not receiving ASA within the previous 7 days. Pharmacodynamic analyses were performed at five time points: baseline, and 1, 2, 4 and 12 h after the loading dose, and measured as ASA reaction units (ARU) by the Verify Now System. An ARU more than 550 was considered as nonresponsiveness to study drugs. The primary end point was the different rate of patients with ARU more than 550 at 2 h after the loading dose of oral vs. intravenous ASA. Secondary end points included the comparison of ARU more than 550 at the other time points and the comparison of continuous ARU at each time point. RESULTS: The study was planned with a sample size of 68 patients, but it was prematurely stopped due to slow enrollment after the inclusion of 23 patients, 12 randomized to oral ASA and 11 to intravenous lysine acetylsalicylate. At 2 h the rate of patients with ARU more than 550 was numerically but not significantly higher in patients receiving oral ASA as compared with intravenous lysine acetylsalicylate (33 vs. 14.2%; Δ -0.19, 95% confidence interval -0.59-0.21, P = 0.58). The difference over time was NS (P = 0.98), though the prevalence of ARU more than 550 was higher at the other time points. Both routes of administration reduced ARU values over time, though with no overall significant difference between profiles (P overall = 0.48). CONCLUSION: In patients with STEMI undergoing pPCI the rate of nonresponsiveness to ASA was not different comparing an oral 'noncoated' loading dose of ASA with an intravenous bolus injection of lysine acetylsalicylate. However, as patient enrollment was prematurely terminated, this study is underpowered to draw a definite conclusion.

Comparison of Nausea and Vomiting Associated With Amino Acid Formulations Coinfused With Peptide Receptor Radionuclide Therapy: Commercial Parenteral Nutrition Formulas Versus Compounded Arginine/Lysine.

OBJECTIVES: Positively charged amino acids (AA) such as arginine/lysine are coinfused with radiolabeled somatostatin analogs to reduce rates of nephrotoxicity. In the phase 3 NETTER-1 trial, commercial AA formulations were used in association with 177Lu-DOTA-0-Tyr3-Octreotate (DOTATATE). These formulations were also used in an early-access program (EAP) before regulatory approval of 177Lu-DOTATATE. Our program transitioned to compounded l-arginine 2.5%/l-lysine 2.5% in 0.9% NaCl after commercial approval of 177Lu-DOTATATE. We sought to compare rates of nausea/vomiting with arginine/lysine versus commercial parenteral AA formulations. METHODS: Rates of nausea/vomiting of all 20 EAP patients who received commercial AAs (15% Clinisol) were compared with the first 29 patients to receive 177Lu-DOTATATE after commercial approval and coinfused with arginine/lysine. Other parameters reviewed included infusion rates, need for PRN nausea medications, and other toxicities. RESULTS: Seventeen percent of patients who received compounded arginine/lysine experienced nausea, compared with 100% of patients in the EAP group (P < 0.0001). Infusion-related reactions occurred in 3% of the arginine/lysine cohort versus 35% in the EAP group. Infusion durations were substantially shorter in the arginine/lysine cohort (reduced by 61%). CONCLUSIONS: Coinfusions of arginine/lysine with radiolabeled somatostatin analogs result in substantially lower rates of nausea/vomiting compared with commercial AA formulations designed for parenteral nutrition.

Effects of low-crude protein diets supplemented with rumen-protected lysine and methionine on fattening performance and nitrogen excretion of Holstein steers.

The objective of this experiment was to investigate the effects of low-crude protein (CP) diets supplemented with rumen-protected lysine and methionine on growth performance, nitrogen excretion, and carcass traits in Holstein steers. Steers consumed the following diets: (1) 17.2% CP on a dry-matter basis during the early period (from 7 to 10 months of age) and 14.5% CP during the late period (from 10 to 18 months of age; CON, n = 4, initial body weight [BW] 238 kg), and (2) 14.4% CP during the early period and 11.4% CP during the late period (AA, n = 4, initial BW 243 kg). The AA diet contains rumen-protected lysine and methionine. Except for CP intake, feed intake and body weight gain were not affected by dietary CP content. Total nitrogen excretion per metabolic BW tended to be lower (p < .10) in the early period and significantly lower (p < .05) in the late period with decreasing the feed CP content. Plasma urea nitrogen concentrations were lower in AA than CON. Carcass traits and total free amino acid contents of the longissimus thoracis muscle were not affected by dietary CP content. Adding rumen-protected lysine and methionine to a low-CP diet would reduce nitrogen excretion in fattening Holstein steers without affecting productivity.

Monitoring PSMA Responses to ADT in Prostate Cancer Patient-Derived Xenograft Mouse Models Using [18F]DCFPyL PET Imaging.

PURPOSE: PSMA overexpression has been associated with aggressive prostate cancer (PCa). However, PSMA PET imaging has revealed highly variable changes in PSMA expression in response to ADT treatment ranging from increases to moderate decreases. To better understand these PSMA responses and potential relationship to progressive PCa, the PET imaging agent, [18F]DCFPyL, was used to assess changes in PSMA expression in response to ADT using genomically characterized LuCaP patient-derived xenograft mouse models (LuCaP-PDXs) which were found to be sensitive to ADT (LuCaP73 and LuCaP136;CS) or resistant (LuCaP167;CR). METHODS: [18F]DCFPyL (2-(3-{1-carboxy-5-[(6-[18F]fluoro-pyridine-3-carbonyl)-amino]-pentyl}-ureido)-pentanedioic acid) was used to assess PSMA in vitro (saturation assays) in LuCaP tumor membrane homogenates and in vivo (imaging/biodistribution) in LuCaP-PDXs. Control and ADT-treated LuCaPs were imaged before ADT (0 days) and 2-, 7-, 14-, and 21-days post-ADT from which tumor:muscle ratios (T:Ms) were determined and concurrently tumor volumes were measured (caliper). After the 21-day imaging, biodistributions and histologic/genomic (PSMA, AR) analysis were done. RESULTS: [18F]DCFPyL exhibited high affinity for PSMA and distinguished different levels of PSMA in LuCaP tumors. Post-ADT CS LuCaP73 and LuCaP136 tumor volumes significantly decreased at day 7 or 14 respectively vs controls, whereas the CR LuCaP167 tumor volumes were minimally changed. [18F]DCFPyL imaging T:Ms were increased 3-5-fold in treated LuCaP73 tumors vs controls, while treated LuCaP136 T:Ms remained unchanged which was confirmed by day 21 biodistribution results. For treated LuCaP167, T:Ms were decreased (~ 45 %) vs controls but due to low T:M values (<2) may not be indicative of PSMA level changes. LuCaP73 tumor PSMA histologic/genomic results were comparable to imaging/biodistribution results, whereas the results for other tumor types varied. CONCLUSION: Tumor responses to ADT varied from sensitive to resistant among these LuCaP PDXs, while only the high PSMA expressing LuCaP model exhibited an increase in PSMA levels in response to ADT. These models may be useful in understanding the clinical relevance of PSMA PET responses to ADT and potentially the relationship to disease progression as it may relate to the genomic signature.

Dietary Lysine Levels Improved Antioxidant Capacity and Immunity via the TOR and p38 MAPK Signaling Pathways in Grass Carp, Ctenopharyngodon idellus Fry.

An 8-week rearing trial was designed to appraise the dietary lysine levels on intestinal antioxidant capacity and immunity of grass carp fry. Six practical diets were prepared with graded levels of lysine (1.44, 1.79, 1.97, 2.44, 2.56 and 2.87% dry matter), and these diets were fed to grass carp fry. The results showed that the activities of intestinal antioxidant factors including catalase and glutathione peroxidase were markedly improved by the 2.44% dietary lysine compared with the control diet (1.44% dietary lysine) (P < 0.05). In terms of antioxidants, compared with the control diet, the 2.44% diet markedly upregulated the mRNA expression levels of target of rapamycin, S6 kinase1 and nuclear factor erythroid 2-related factor 2 pathway-related antioxidant genes, containing catalase and glutathione peroxidase 1α (P < 0.05) and downregulated the mRNA levels of Kelch-like ECH-associated protein 1 (P > 0.05). The mRNA levels of 4E-binding protein 2 showed the opposite trend compared with those of target of rapamycin, and the minimum value was observed in the group of 1.97% dietary lysine (P < 0.05). In terms of immunity, compared with the 1.44% diet, the 2.44% diet markedly suppressed the intestinal p38 mitogen-activated protein kinase and interferon γ2 mRNA levels (P < 0.05). Moreover, nuclear factor-kappa B p65, tumor necrosis factor α, interleukin 6, interleukin 8, and interleukin 15 mRNA levels all exhibited the same trend as p38 mitogen-activated protein kinase and interferon γ2; however, the difference among all the lysine treatments groups was not significant (P > 0.05). The anti-inflammatory cytokines transforming growth factor ß2 and interleukin 4/13B mRNA levels in the intestine were remarkably upregulated by high dietary lysine levels (2.56 and 2.87%) (P < 0.05), and when the dietary lysine level reached 2.44%, the interleukin 4/13A mRNA levels were strikingly increased (P < 0.05). Overall, the data suggested that 2.44% dietary lysine could strengthen the immune and antioxidant capacities of grass carp fry via activating the target of rapamycin (TOR) signaling pathway, and suppressing the p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway, which then improve the survival rate.

Growth performance and accretion of selected amino acids in response to three levels of dietary lysine fed to fast- and slow-growing broilers.

Literature data indicate that feed intake is sensitive to the dietary Lys content particularly in fast-growing birds. From a conceptual and a practical viewpoint, an interaction between genotype (i.e., fast-growing vs. slow-growing birds) and dietary Lys content is of interest, but it needs confirmation owing to a dearth of studies addressing this issue. A study was conducted with 266 Cobb 500 birds and 266 Thai native crossbreed birds serving as models for fast-growing broilers (FGB) and slow-growing broilers (SGB), respectively. Within genotype, chicks were randomly allocated to diets containing either a high (H-LYS = 1.36%), medium (1.17%), or low Lys (1.01%) content. Growth performance and the accretion of protein and selected amino acids were determined in birds from 1 to 21 d of age. Treatments were arranged in a factorial design with 6 replications/treatment. Low Lys vs. H-LYS caused a 42.1% lower feed intake in FGB (P < 0.001), but not in SGB (P = 0.596). The feed conversion ratio (FCR (g feed/g BW gain)) was lowest in FGB (P < 0.001) and increased with decreasing dietary Lys contents (P < 0.001). The Lys induced increase in FCR, however, was more pronounced in SGB (P = 0.025). The absolute protein gain (g/bird) was influenced by the Lys content of feed and decreased by ∼54% and ∼23% in FGB and SGB, respectively (P < 0.001). The efficiency (% of intake) of protein accretion was found to be greater in FGB (P ≤ 0.001) and decreased with decreasing dietary Lys (P ≤ 0.001). The efficiency of Lys accretion was found to be negatively affected by the dietary Lys content in FGB (P < 0.001) but not SGB (Pgenotype × dietary Lys = 0.008). It can be concluded that a dietary Lys content of 1.01% does not safeguard both growth performance and body protein accretion efficiency in both FGB and SGB. The suboptimal growth performance in FGB, but not SGB, is partially counteracted by a Lys-induced reduction in feed intake.

In vitro dissolution behaviour and absorption in humans of a novel mixed l-lysine salt formulation of EPA and DHA.

INTRODUCTION: Supplements with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are generally oil-based formulations containing their triacylglycerols, phospholipids or ethyl-esters (EE). Recently, a l-lysine salt of carboxylic EPA and DHA became available (Lys-FFA), which necessitated to study its oral absorption and plasma kinetics in humans. OBJECTIVES: The in vitro dissolution characteristics, oral bioavailability and 48 h plasma profiles of EPA and DHA (as triacylglycerides) of Lys-FFA, relative to a commercially available oil-based EE supplement. METHODS: Dissociation of the lysine from the FFAs was studied in vitro applying simulated gastric (12 h) and intestinal (3 h) conditions. In an open label, randomized, two-way cross-over design, oral administration of Lys-FFA (500 mg EPA plus 302 mg DHA) versus EE (504 mg EPA plus 378 mg DHA) was studied over 48 h, in eight female volunteers. Plasma profiles of EPA and DHA were described by Area Under the Curve (AUC; 0-12 h), Cmax and Tmax. RESULTS: Dissolution studies with Lys-FFA showed complete dissociation under both conditions. In volunteers Lys-FFA showed rapid absorption and high bioavailability indicated by significant differences in both the AUC0-12hr and Cmax when compared to the EE comparator (p<0.001), with AUC0-12hr which was for EPA 5 times higher with Lys-FFA than with the EE formulation. CONCLUSION: This first-in-man study of Lys-FFA demonstrated rapid absorption of EPA and DHA and a considerably higher bioavailability compared to an EE supplement under fasting conditions. The release and absorption characteristics from this solid form offer several new options in terms of formulation technology and dosing.

Relative availability of metabolizable methionine from 2 ruminally protected sources of methionine fed to lactating dairy cattle.

Our objective was to evaluate the lactational responses of dairy cows to methionine provided from 2 ruminally protected sources of methionine activity. Twenty-one Holstein dairy cows [11 primiparous (634 kg of body weight, 140 d in milk) and 10 second-parity (670 kg of body weight, 142 d in milk)] were assigned to a treatment sequence in 4 replicated 5 × 5 Latin squares plus 1 cow, with 14-d periods. Treatments were as follows: control; 7.5 or 15 g/d of a ruminally protected product of 2-hydoxy-4-methylthio-butyric acid (NTP-1401; Novus International Inc., St. Charles, MO); or 7.5 or 15 g/d of a ruminally protected dl-methionine product (Smartamine M; Adisseo, Alpharetta, GA). The diet was predicted to meet metabolizable protein and energy requirements. Diets contained 16.1% crude protein, and the control diet was predicted to be deficient in metabolizable methionine (1.85% of metabolizable protein) but sufficient in lysine (6.8% of metabolizable protein). Feed intake and milk yield were measured on d 11 to 14. Blood was collected on d 14. Dry matter intake, milk yield, energy-corrected milk, milk fat yield and percentage, and efficiencies of milk and energy-corrected milk yield were not affected by treatment. Milk protein percentage and milk protein yield increased linearly with supplementation, without differences between methionine sources or interactions between source and level. Linear regressions of milk protein percentage and milk protein yield against supplement amount within source led to slope ratios (NTP-1401:Smartamine M) of 95% for protein percentage and 84% for protein yield, with no differences between sources for increasing milk protein. Plasma methionine concentrations were increased linearly by methionine supplementation; the increase was greater for Smartamine M than for NTP-1401. Plasma d-methionine was increased only by Smartamine M. Plasma 2-hydoxy-4-methylthio-butyric acid was increased only by NTP-1401. Our data demonstrated that supplementation with these methionine sources can improve milk protein percentage and yield, and the 2 methionine sources did not differ in their effect on lactation performance or milk composition.

Avaliação nutricional e metabólica de borregas alimentadas com níveis crescentes de aminoácidos protegidos / [Nutritional and metabolic evaluation of feeding lambs with growing levels of protein amino acids]

Objetivou-se avaliar a inclusão de níveis de lisina e metionina protegidas na dieta sobre os parâmetros nutricionais e metabólicos energéticos e hepáticos de borregas em crescimento. Utilizaram-se cinco borregas ½ sangue Dorper x Santa Inês, com aproximadamente oito meses de idade e peso médio de 50 ± 2,3kg, distribuídas em esquema quadrado latino 5x5 (cinco tratamentos, cinco animais e cinco períodos). Os tratamentos consistiram na inclusão de diferentes níveis de lisina e metionina protegidas da degradação ruminal (MicroPEARLS LM®) na ração, sendo: 0g, 8g, 16g, 24g e 32g por dia. A dieta era composta por silagem de milho e concentrado na relação 30V:70C. Realizou-se um ensaio de digestibilidade para determinar consumo e digestibilidade da matéria seca (CMS/DGMS), balanço de nitrogênio e metabólitos sanguíneos. O CMS (kg/dia) em relação ao peso metabólico apresentou equação linear positiva, sendo maior no tratamento que ofertou 32g de aminoácidos por dia, assim como o nitrogênio ingerido e o balanço de nitrogênio, sendo positivo em todos os tratamentos. Não houve diferença (P>0,05) para a digestibilidade da MS e o metabolismo energético e hepático. Lisina e metionina protegidas da degradação ruminal podem ser incluídas na ração de borregas em crescimento até 32g/dia sem causar efeitos negativos na digestibilidade da MS e no metabolismo.(AU)

The objective was to evaluate the inclusion of protected lysine and methionine levels on the diet, over the nutritional parameters and energetic and hepatic metabolites of growing lambs. Five lambs ½ blood Dorper x Santa Inês, with approximately eight months of age and average weight of 50kg, were distributed in a 5x5 latin square scheme (five treatments and five replicates). The treatments consisted of the inclusion of different levels of lysine and methionine protected from ruminal degradation (MicroPEARLS LM®) in the diet, being: 0g, 8g, 16g, 24g and 32g. The diet was composed of corn silage and concentrated 30V:70C in the ratio. A digestibility assay was performed to determine dry matter intake and digestibility (DMI/DDMI), nitrogen balance and blood metabolites. The DMI (kg/day) in relation to the metabolic weight had a positive linear equation, being higher in treatment 32g, as well as the ingested nitrogen and nitrogen balance, being positive in all treatments. There was no difference (P>0.05) for the digestibility of DM, energetic and hepatic metabolism. Lysine and methionine protected from ruminal degradation can be included in the diet of growing lambs up to 32g without causing negative effects on DM digestibility and metabolism.(AU)

Feeding rumen-protected lysine prepartum increases energy-corrected milk and milk component yields in Holstein cows during early lactation.

Feeding rumen-protected Lys (RPL) may be used to increase lactation performance in dairy cows; however, the effect of feeding RPL during the prepartum period and subsequent effect on postpartum performance is not well explored. Therefore, this experiment was conducted to determine the effects of feeding RPL (AjiPro-L Generation 3, Ajinomoto Heartland Inc., Chicago, IL) prepartum, postpartum, or both on performance, health, and blood metabolites. Seventy-five multiparous Holstein cows, blocked by parity, previous 305-d mature-equivalent milk production, expected calving date, and body condition score during the far-off dry period were assigned to 1 of 2 dietary treatments: total mixed ration with or without RPL in a randomized, complete block design. A 2 × 2 factorial arrangement of treatments was used. Prepartum (-28 d to calving), animals were fed a diet (forage, 68% of dietary DM) with RPL [PRE-L; 0.54% RPL of dietary dry matter intake (DMI)] or without RPL (control; PRE-C). After calving, half of the cows from each prepartum treatment group were assigned to a diet (forage, 55.5% of dietary DM) with RPL (PRE-L POST-L; PRE-C POST-L; 0.40% RPL of dietary DMI) or without RPL (PRE-C POST-C; PRE-L POST-C) until d 28 postpartum. Cows were milked twice a day and milk samples were taken on 7 ± 1.3, 14 ± 1.4, and 28 ± 1.1 d relative to calving (DRC). Milk yield and DMI were recorded daily. Blood samples were taken for plasma AA analysis on -7 ± 0.5, 0 ± 0.5, 7 ± 0.9, and 14 ± 0.9 DRC. Cows in PRE-L had greater body weight at -2 and -1 wk before calving compared with those in PRE-C, though body weight change from wk -4 to -1 was not different. Body weight (717 ± 6 kg) was greater and DMI (18.1 ± 0.7 kg) tended to be greater for cows in PRE-L POST-L and PRE-L POST-C compared with those that were in PRE-C POST-L and PRE-C POST-C (707 ± 6 and 16.8 ± 0.7 kg, respectively). Energy-corrected milk (48.8 ± 1.9 kg/d), milk fat (1.9 ± 0.1 kg/d), milk true protein (1.4 ± 0.1 kg/d), milk casein (0.6 ± 0.04 kg/d), and milk lactose yields (2.1 ± 0.1 kg/d) were greater for cows in PRE-L POST-L and PRE-L POST-C compared with those that were in PRE-C POST-L and PRE-C POST-C (44.2 ± 1.9, 1.7 ± 0.1, 1.3 ± 0.1, 0.5 ± 0.04, 1.9 ± 0.1 kg/d, respectively). Plasma concentrations of Lys prepartum (69.8 ± 1.8 µM) increased for cows in PRE-L compared with those in PRE-C (62.5 ± 1.3 µM). In conclusion, RPL consumed prepartum tended to increase postpartum DMI and increased energy-corrected milk and milk component yields. This indicates that prepartum supply of intestinally available Lys is pertinent to postpartum performance. However, postpartum supply of intestinally available Lys had no effect on cows' performance.

Lysine Bioavailability in School-Age Children Consuming Rice Is Reduced by Starch Retrogradation.

BACKGROUND: Rice is one of the most commonly consumed cereal grains and is part of staple diets in the majority of the world. However, it is regarded as an incomplete protein, with lysine being a limiting amino acid. OBJECTIVES: Our objectives were to determine the bioavailability of lysine in school-age children consuming cooked white rice and to assess the effect of rice starch retrogradation. METHODS: Bioavailability or metabolic availability (MA) of lysine was determined using the indicator amino acid oxidation (IAAO) method in a repeated-measures design. Six healthy school-age children (3 boys, 3 girls) with a mean ± SD age of 6.8 ± 0.98 y randomly received 4 crystalline l-lysine intakes (2, 6, 10, 14 mg · kg-1 · d-1), and 5 rice intakes to provide lysine at 8, 11, or 14 mg · kg-1 · d-1. The 14 mg · kg-1 · d-1 intakes were measured twice as warm rice and once as cold rice (to assess the impact of starch retrogradation on MA). Diets provided protein at 1.5 g · kg-1 · d-1 and calories at 1.7 times the participant's measured resting energy requirement, and were isonitrogenous. Breath samples were collected at baseline and during an isotopic steady state for 13C enrichment measurement. The MA of lysine from rice was determined by comparing the IAAO response of rice with l-lysine using the slope-ratio and single intake methods. Starch retrogradation was characterized using differential scanning calorimetry. RESULTS: MA of lysine in warm rice measured in school-age children was 97.5% and was similar to a repeated rice study (97.1%) within the same study population. MA of lysine was reduced significantly (P < 0.05) to 86.1% when the cooked rice was consumed cold, which corresponded to detectable starch retrogradation. CONCLUSIONS: To our knowledge, this is the first study to measure the MA of lysine from rice in school-age children. Although the bioavailability of lysine from rice is high, it can be reduced by retrogradation of its starch component.This trial was registered at clinicaltrials.gov as NCT04135040.

Lysine is required for growth factor-induced mTORC1 activation.

Mechanistic target of rapamycincomplex 1 (mTORC1) integrates various environmental signals to regulate cell growth and metabolism. mTORC1 activity is sensitive to changes in amino acid levels. Here, we investigated the effect of lysine on mTORC1 activity in non-small cell lung cancer (NSCLC) cells. Lysine deprivation suppressed mTORC1 activity and lysine replenishment restored the decreased mTORC1 activity in lysine-deprived cells. Supplementing growth factors, such as insulin growth factor-1 or insulin restored the decreased mTORC1 activity in serum-deprived cells. However, in serum/lysine-deprived cells, supplementing growth factors was not sufficient to restore mTORC1 activity, suggesting thatgrowth factors could not activate mTORC1 efficiently in the absence of lysine. General control nonderepressible 2 and AMP-activated protein kinase were involved in lysine deprivation-mediated inhibition of mTORC1. Taken together, these results suggest that lysine might play role in the regulation of mTORC1 activation in NSCLC cells.

Comprehensive Safety Assessment of l-Lysine Supplementation from Clinical Studies: A Systematic Review.

BACKGROUND: Despite the widespread use of l-lysine in dietary supplements, the safety information pertinent to excessive l-lysine ingestion is limited and, to the best of our knowledge, there is no published systematic review of safety. OBJECTIVE: The objective of this study was to assess the clinical safety of l-lysine supplementation of a regular diet. METHODS: We searched PubMed, Cochrane Library, Ichushi Web, and EBSCOhost using the relevant keywords, "l-lysine" and "clinical trial." To investigate all adverse events observed during intervention trials, we included all intervention studies with orally ingested l-lysine without restricting background factors, environment, study designs, and sample sizes. RESULTS: We identified 71 articles, which included 3357 study subjects. The l-lysine doses ranged from 16.8 to 17.5 g/d, and the dosing period ranged from 1 to 1095 d. The observed adverse events were mainly subjective gastrointestinal tract symptoms; however, the risk analysis for incidence of gastrointestinal symptoms was not statistically significant (risk ratio of 1.02). CONCLUSION: The provisional no-observed-adverse-effect level in healthy human subjects was based on gastrointestinal symptoms and identified at 6.0 g/d. The review protocol was registered at umin.ac.jp as UMIN000028914 before the beginning of the study.

Proposals for Upper Limits of Safe Intake for Methionine, Histidine, and Lysine in Healthy Humans.

Based on research presented during the 10th Amino Acid Assessment Workshop, no observed adverse effect levels (NOAELs) for supplemental methionine at 46 mg/(kg·d) (∼3.2 g/d), for supplemental histidine at 8.0 g/d, and for supplemental lysine at 6.0 g/d have been proposed. These NOAELs are relevant to healthy adults and are applicable only to high-purity amino acids administered in fortified foods or dietary supplements. Because individuals are exposed to the above supplemental amino acids in the context of complex combinations of essential amino acids or individually in dietary supplements for various physiologic benefits, such as body fat reduction, skin conditioning, mental energy increase, or herpes simplex treatments, the above safety recommendations will make an important contribution to regulatory and nutritional practices.

Use of encapsulated L-lysine-HCl and DL-methionine improves postprandial amino acid balance in laying hens.

The supplementation of dietary limiting amino acids (AA) with crystalline AA makes the use of low-protein diets an option in poultry production. The differing absorption rates of crystalline and protein-bound AA may lead to temporally imbalanced AA in the postabsorptive period. In this study, two experiments were conducted to evaluate the effect of encapsulated L-lysine-HCl (L-Lys-HCl) and DL-methionine (DL-Met) on the laying performance of hens. In exp. 1, a total of 135 forty-seven-wk-old Hy-Line Brown hens were subjected to three dietary treatments for 8 wk: basal diet supplemented with 0.14% L-Lys-HCl and 0.17% DL-Met to satisfy the NRC (1994) total Lys and Met recommendation (control) and basal diet supplemented with encapsulated L-Lys-HCl and DL-Met at the levels of 60% (60CLM, 0.084% L-Lys-HCl and 0.102% DL-Met) or 80% of control (80CLM, 0.112% L-Lys-HCl and 0.136% DL-Met), respectively. In exp. 2, 24 fifty-five-wk-old Hy-Line Brown hens were individually reared in cages and subjected to the same treatments as in exp. 1. The plasma concentrations of free AA and nitrogen metabolites were measured 2, 4, and 6 h after fed. The results showed that dietary AA treatment had no significant influence on body weight (BW), feed intake, laying rate, egg weight, egg mass, or feed efficiency. The expression levels of AA transporters CAT-1, y+LAT1, b0,+AT, B0AT, rBAT, EAAT3, and PepT1 in the duodenum, jejunum, and ileum were not influenced (P > 0.05) by dietary treatment. There was an interaction of dietary AA treatment and time (P < 0.05) and the 80CLM hens exhibited higher concentrations of Lys (P < 0.05) than the controls at 2-h time point. In contrast, plasma Met concentration was not influenced (P > 0.05), while Cys was reduced in the 60CLM hens at every time point. The 80CLM hens had higher taurine concentrations than those receiving the control diet at every postprandial time point. In conclusion, these findings demonstrate that by using encapsulated form, the supplemental levels of synthetic L-Lys-HCl and DL-Met can be effectively reduced by approximately 20% with no negative effect on laying performance. The result suggests that encapsulated Lys and Met may ameliorate the postabsorptive AA balance and contribute to the reduced dietary AA supplemental levels.