The Mediating Role of Kynurenine Pathway Metabolites on the Relationship Between Inflammation and Muscle Mass in Oldest-Old Men.

Tryptophan (TRP) metabolites along the kynurenine (KYN) pathway (KP) have been found to influence muscle. Proinflammatory cytokines are known to stimulate the degradation of TRP down the KP. Given that both inflammation and KP metabolites have been connected with loss of muscle, we assessed the potential mediating role of KP metabolites on inflammation and muscle mass in older men.

Liver glycogen stores via C magnetic resonance spectroscopy in healthy children: randomized, controlled study.

Background: Owing to its role in glucose homeostasis, liver glycogen concentration ([LGly]) can be a marker of altered metabolism seen in disorders that impact the health of children. However, there is a paucity of normative data for this measure in children to allow comparison with patients, and time-course assessment of [LGly] in response to feeding has not been reported. In addition, carbon-13 magnetic resonance spectroscopy (C-MRS) is used extensively in research to assess liver metabolites in adult health and disease noninvasively, but similar measurements in children are lacking.

Effect of an enteral amino acid blend on muscle and gut functionality in critically ill patients: a proof-of-concept randomized controlled trial.

Background: A defining feature of prolonged critical illness is muscle wasting, leading to impaired recovery. Supplementation with a tailored blend of amino acids may bolster the innate gut defence, promote intestinal mucosa repair and limit muscle loss.

Methods: This was a monocentric, randomized, double-blind, placebo-controlled study that included patients with sepsis or acute respiratory distress syndrome.

Association of amino acid metabolites with osteoporosis, a metabolomic approach: Bushehr elderly health program.

Introduction And Objectives: Amino acids are the most frequently reported metabolites associated with low bone mineral density (BMD) in metabolomics studies. We aimed to evaluate the association between amino acid metabolic profile and bone indices in the elderly population.

Methods: 400 individuals were randomly selected from 2384 elderly men and women over 60 years participating in the second stage of the Bushehr elderly health (BEH) program, a population-based prospective cohort study that is being conducted in Bushehr, a southern province of Iran.

Supplementation with Whey Protein, Omega-3 Fatty Acids and Polyphenols Combined with Electrical Muscle Stimulation Increases Muscle Strength in Elderly Adults with Limited Mobility: A Randomized Controlled Trial.

Age-related sarcopenia is a progressive and generalized skeletal muscle disorder associated with adverse outcomes. Herein, we evaluate the effects of a combination of electrical muscle stimulation (EMS) and a whey-based nutritional supplement (with or without polyphenols and fish oil-derived omega-3 fatty acids) on muscle function and size. Free-living elderly participants with mobility limitations were included in this study.

Development of the Nutrition and Functionality Assessment (NFA) among Older Adults in Japan.

Objective: Develop and evaluate the feasibility and validity of the Nutrition and Functionality Assessment (NFA) which identifies "target" older adults who could benefit from a personalized program following evaluation of their nutrition status and physical functionality.

Design: Cross-sectional study.

Setting: Community and geriatric day-care centers and university in Japan.

Protein Intake at Breakfast Promotes a Positive Whole-Body Protein Balance in a Dose-Response Manner in Healthy Children: A Randomized Trial.

Background: Protein ingestion promotes whole-body net protein balance (NB) in children, which is a prerequisite for growth. Determining how much protein is required at breakfast to promote a positive NB, which may be negative after the traditional overnight fast in children, has yet to be determined.

Objective: We determined the impact of incremental doses of milk protein at breakfast as well as the impact of daily dietary protein distribution on NB in children.

Long-term dietary supplementation with cystathionine improves tissue glutathione in ageing rats.

Background: Ageing is associated with decrease in tissue glutathione that can be reduced by food fortification with the amino acid cysteine. However, cysteine is not stable in solution and generates bad taste. Cystathionine, the direct precursor of cysteine, could be a valuable alternative.

Low-load resistance training during step-reduction attenuates declines in muscle mass and strength and enhances anabolic sensitivity in older men.

Step-reduction (SR) in older adults results in muscle atrophy and an attenuated rise in postprandial muscle protein synthesis (MPS): anabolic resistance. Knowing that resistance exercise (RT) can enhance MPS, we examined whether RT could enhance MPS following 2 weeks of SR. In addition, as we postulated that SR may impair feeding-induced vasodilation limiting nutrient delivery to muscle, we also examined whether citrulline (CIT), as an arginine and nitric oxide precursor, could attenuate muscle anabolic resistance accompanying SR.

A dietary supplementation with leucine and antioxidants is capable to accelerate muscle mass recovery after immobilization in adult rats.

Prolonged inactivity induces muscle loss due to an activation of proteolysis and decreased protein synthesis; the latter is also involved in the recovery of muscle mass. The aim of the present work was to explore the evolution of muscle mass and protein metabolism during immobilization and recovery and assess the effect of a nutritional strategy for counteracting muscle loss and facilitating recovery. Adult rats (6-8 months) were subjected to unilateral hindlimb casting for 8 days (I0-I8) and then permitted to recover for 10 to 40 days (R10-R40).

Leucine supplementation of a low-protein mixed macronutrient beverage enhances myofibrillar protein synthesis in young men: a double-blind, randomized trial.

Background: Leucine is a key amino acid involved in the regulation of skeletal muscle protein synthesis.

Objective: We assessed the effect of the supplementation of a lower-protein mixed macronutrient beverage with varying doses of leucine or a mixture of branched chain amino acids (BCAAs) on myofibrillar protein synthesis (MPS) at rest and after exercise.

Design: In a parallel group design, 40 men (21 ± 1 y) completed unilateral knee-extensor resistance exercise before the ingestion of 25 g whey protein (W25) (3.

Long-term cysteine fortification impacts cysteine/glutathione homeostasis and food intake in ageing rats.

Purpose: Healthy ageing is associated with higher levels of glutathione. The study aimed to determine whether long-term dietary fortification with cysteine increases cysteine and glutathione pools, thus alleviating age-associated low-grade inflammation and resulting in global physiological benefits.

Methods: The effect of a 14-week dietary fortification with cysteine was studied in non-inflamed (NI, healthy at baseline) and in spontaneously age-related low-grade inflamed (LGI, prefrail at baseline) 21-month-old rats.

Effect of citrulline on muscle functions during moderate dietary restriction in healthy adult rats.

Low calorie diets are designed to reduce body weight and fat mass, but they also lead to a detrimental loss of lean body mass, which is an important problem for overweight people trying to lose weight. In this context, a specific dietary intervention that preserves muscle mass in people following a slimming regime would be of great benefit. Leucine (LEU) and Citrulline (CIT) are known to stimulate muscle protein synthesis (MPS) in post-prandial and post-absorptive state, respectively.

Chronic α-hydroxyisocaproic acid treatment improves muscle recovery after immobilization-induced atrophy.

Muscle disuse atrophy is observed routinely in patients recovering from traumatic injury and can be either generalized resulting from extended bed rest or localized resulting from single-limb immobilization. The present study addressed the hypothesis that a diet containing 5% α-hydroxyisocaproic acid (α-HICA), a leucine (Leu) metabolite, will slow the loss and/or improve recovery of muscle mass in response to disuse. Adult 14-wk-old male Wistar rats were provided a control diet or an isonitrogenous isocaloric diet containing either 5% α-HICA or Leu.

Intestinal inflammation influences α-MSH reactive autoantibodies: relevance to food intake and body weight.

Autoantibodies reacting with alpha-melanocyte-stimulating hormone (α-MSH), an anorexigenic neuropeptide, are involved in regulation of feeding. In this work we studied if intestinal inflammation (mucositis) may influence α-MSH autoantibodies production relevant to food intake and body weight. Mucositis and anorexia were produced in Sprague-Dawley rats by methotrexate (MTX, 2.

Sarcopenia: an undiagnosed condition in older adults. Current consensus definition: prevalence, etiology, and consequences. International working group on sarcopenia.

Sarcopenia, the age-associated loss of skeletal muscle mass and function, has considerable societal consequences for the development of frailty, disability, and health care planning. A group of geriatricians and scientists from academia and industry met in Rome, Italy, on November 18, 2009, to arrive at a consensus definition of sarcopenia. The current consensus definition was approved unanimously by the meeting participants and is as follows: Sarcopenia is defined as the age-associated loss of skeletal muscle mass and function.

Presence of age-associated low-grade inflammation does not worsen the body response to bacterial infection in old male rats.

In the field of frailty, there is an underlying hypothesis that chronic low-grade inflammation contributes to bad outcomes in response to a stressor. The host response to an Escherichia coli infection was assessed in 24 month old male rats exhibiting a chronic low-grade inflammation and in non-inflamed control rats. Mortality, weight loss and sarcopenia were the main outcomes measured.

Chemotherapy-induced anorexia is accompanied by activation of brain pathways signaling dehydration.

Background And Aims: Cancer chemotherapy is accompanied by anorexia and mucositis. To clarify the mechanisms of chemotherapy-induced anorexia, we studied the expression of c-fos and appetite-regulating neuropeptidergic and inflammatory mediators in the hypothalamus of rats treated with methotrexate (MTX).

Methods: Sprague-Dawley rats received MTX (2.

Beneficial effects of cathepsin inhibition to prevent chemotherapy-induced intestinal mucositis.

One of the main secondary toxic side effects of anti-mitotic agents used to treat cancer patients is intestinal mucositis. Previous data showed that cathepsin D activity, contributing to the proteolytic lysosomal pathway, is up-regulated during intestinal mucositis in rats. At the same time, cathepsin inhibition limits intestinal damage in animal models of inflammatory bowel diseases.

Cysteine fluxes across the portal-drained viscera of enterally fed minipigs: effect of an acute intestinal inflammation.

Cysteine is considered as a conditionally indispensable amino acid. Its dietary supply should thus be increased when endogenous synthesis cannot meet metabolic need, such as during inflammatory diseases. However, studies in animal models suggest a high first-pass extraction of dietary cysteine by the intestine, limiting the interest for an oral supplementation.

A diet containing whey protein, free glutamine, and transforming growth factor-beta ameliorates nutritional outcome and intestinal mucositis during repeated chemotherapeutic challenges in rats.

Anticancer chemotherapy often induces side effects such as mucositis. Recent data suggest that a diet, Clinutren Protect (CP), containing whey proteins, glutamine, and transforming growth factor-beta (TGFbeta)-rich casein limits intestinal mucositis and improves recovery after a single methotrexate (MTX) challenge in rats. Chemotherapy consists of alternating periods of treatment and rest.

A diet containing whey protein, glutamine, and TGFbeta modulates gut protein metabolism during chemotherapy-induced mucositis in rats.

Background: Mucositis, a common side effect of chemotherapy, is characterized by compromised digestive function, barrier integrity and immune competence.

Aims: Our aim was to evaluate the impact of a specifically designed diet Clinutren Protect (CP), which contains whey proteins, TGFbeta-rich casein, and free glutamine, on mucositis in rats.

Methods: Mucositis was induced by three consecutive injections (day 0, day 1, day 2) of methotrexate (2.

Simultaneous measurement of 13C- and 15N-isotopic enrichments of threonine by mass spectrometry.

Under conditions of high isotopic dilution, e.g. in a tracer study, the ability to determine accurately and quantitatively small variations in isotopic enrichments of differently labelled chemical compounds (e.

Intestinal inflammation increases gastrointestinal threonine uptake and mucin synthesis in enterally fed minipigs.

The high requirement of the gut for threonine has often been ascribed to the synthesis of mucins, secreted threonine-rich glycoproteins protecting the intestinal epithelium from injury. This requirement could be even greater during intestinal inflammation, when mucin synthesis is enhanced. In this study, we used an animal model to investigate the effects of an acute ileitis on threonine splanchnic fluxes.