Association of Intestinal Amino Acid Absorption with the Uptake of Lactulose and Rhamnose in Adults with Environmental Enteropathy.

It is not clear whether impaired amino acid (AA) absorption occurs in adults with environmental enteropathy (EE). Therefore, we set out to determine the association between intestinal 13C615N-allo-isoleucine absorption (reflecting neutral AA transport) and lactulose-rhamnose ratio (LRR, reflecting permeability) in healthy adult volunteers (aged 18-35 years; N = 6) from India, and in those with biopsy-confirmed EE (N = 20) from Zambia. A 3-hour oral bolus protocol using 13C615N-allo-isoleucine (M), co-administered with lactulose and rhamnose sugars, was used to estimate AA absorption (as M area under the curve [AUC]) and LRR.

The Oral Bioavailability of Vitamin B at Different Doses in Healthy Indian Adults.

Background/objectives: The bioavailability of crystalline vitamin B (B) through active absorption is reported to have a maximum capacity of 1.5-2.5 µg per dose.

Mammalian colonic contribution of amino acids to whole-body homeostasis.

Purpose Of Review: The colon is an effective bioreactor with auxotrophic microbiota that can serve by hydrolyzing dietary and endogenous protein, as well as by synthesizing essential amino acids through nitrogen salvage. Due to assumed negligible amino acid absorption, this colonic contribution was thought to be minimal, but this may not be true.

Recent Findings: Several studies that examined the colonic environment in health and disease, show the presence of proteases in the colonic lumen, which are of both host and microbial origin, along with indirect evidence of amino acid transporters in the colonic epithelium.

True Digestibility of Tryptophan in Plant and Animal Protein.

Background: Protein quality, evaluated using Digestible Indispensable Amino Acid Score (DIAAS), requires ileal digestibility values of individual indispensable amino acids (IAAs) in each protein. However, true tryptophan (Trp) digestibility has rarely been quantified in humans.

Objective: To measure the true Trp digestibility and DIAAS of H-intrinsically labeled plant and animal protein sources in humans, using the dual isotope tracer technique.

Effect of calcium supplementation on reversing metformin-based inhibition of vitamin B bioavailability in healthy adults using a [C] cyanocobalamin tracer - A pilot study.

Background & Aims: Metformin is a widely prescribed first line drug for the treatment of type 2 diabetes mellitus (DM). Studies have shown that the use of metformin is often associated with a decrease in vitamin B (B) levels in patients with DM. Few studies have shown that this effect could be mitigated with calcium supplementation.

Estimation of exocrine pancreatic insufficiency in children with acute pancreatitis using the C mixed triglyceride breath test.

Background: /Objective: The extent of exocrine pancreatic insufficiency (EPI) in the paediatric population with acute pancreatitis (AP) is unknown. The primary objective was to use a 6 h stable-isotope breath test to determine the prevalence of EPI in children with AP. The secondary objective was to determine the diagnostic ability of a 4 h abbreviated breath test in the detection of EPI.

Measurement of True Indispensable Amino Acid Digestibility by the Dual Isotope Tracer Technique: A Methodological Review.

The digestible indispensable amino acid score uses ileal digestibility of each indispensable amino acid (IAA) of a dietary protein to calculate its protein quality. However, true ileal digestibility, which is the exclusive sum of digestion and absorption of a dietary protein up to the terminal ileum, is difficult to measure in humans. It is traditionally measured using invasive oro-ileal balance methods but can be confounded by endogenous secreted protein in the intestinal lumen, although the use of intrinsically labeled protein corrects for this.

The effect of l-arginine supplementation on amelioration of oxygen support in severe COVID-19 pneumonia.

Background & Aims: l-Arginine (l-Arg) has been shown to help reduce respiratory support requirements in coronavirus disease 2019 (COVID-19), in an Italian study. We investigated the effect of l-Arg supplementation on the reduction in respiratory support for patients with severe COVID-19 pneumonia in an Indian population.

Methods: A parallel-group, triple-blinded, randomized controlled trial (RCT) was conducted on patients with severe COVID-19 pneumonia on oxygen (O) support.

Tryptophan oxidation in young children with environmental enteric dysfunction classified by the lactulose rhamnose ratio.

Background: In young children, associations between linear growth faltering, environmental enteric dysfunction (EED), and the plasma kynurenine (Kyn)/tryptophan (Trp) ratio (KTR) have led to the proposal that higher Trp catabolism in response to intestinal/systemic inflammation limits Trp availability for protein synthesis, resulting in impaired growth.

Objectives: We sought to estimate the Trp oxidation rate and the Trp conversion rate to Kyn in young children with and without EED.

Methods: Children aged 18-24 mo, from urban slums, were assigned to EED (n = 19) or no-EED (n = 26) groups on the basis of a urinary lactulose/rhamnose ratio (LRR) cutoff based on mean + 2 SDs of LRR (≥0.

Evaluation of Protein Quality in Humans and Insights on Stable Isotope Approaches to Measure Digestibility - A Review.

The recent Food and Agricultural Organization/World Health Organization/United Nations University expert consultations on protein requirements and quality have emphasized the need for the new Digestible Indispensable Amino Acid Score (DIAAS), as a measure of protein quality. This requires human measurements of the true ileal digestibility of individual indispensable amino acids (IAAs) until the end of the small intestine. Digestibility is measured using standard oro-ileal balance methods, which can only be achieved by an invasive naso-ileal intubation in healthy participants or fistulation at the terminal ileum.

Goat milk protein digestibility in relation to intestinal function.

Background: Milk is an important high-quality animal protein source in low- and middle-income countries (LMICs). Although the true ileal digestibility and absorption of milk has been shown to be high in French adults, this may be lower in individuals from LMICs who are at risk of environmental enteropathy.

Objective: To determine the true ileal indispensable amino acid (IAA) digestibility of intrinsically labeled goat milk protein in South Indian women of reproductive age (WRA), using the dual-isotope tracer technique, and to measure intestinal absorption of amino acid and inert sugar in the same participants using L-allo-isoleucine and a dual-sugar assay.

True ileal digestibility of legumes determined by dual-isotope tracer method in Indian adults.

Background: Good-quality plant protein sources are important for protein adequacy in a balanced diet. Legumes are known to be a source of good quality plant protein, but the true ileal digestibility of indispensable amino acids (IAAs) of commonly consumed legumes is not known in humans.

Objectives: In this study we measured the true ileal IAA digestibility of 2H-intrinsically labeled chickpea, yellow pea, and mung bean (hulled and dehulled) protein, using the dual-isotope tracer technique referenced to a standard protein ([U-13C] spirulina).

Co-ingestion of Black Tea Reduces the Indispensable Amino Acid Digestibility of Hens' Egg in Indian Adults.

Background: Tea, a commonly consumed beverage, contains high amounts of polyphenols that can impair protein digestibility, as demonstrated in vitro. There are no human studies examining the inhibitory influence of tea polyphenols (TPP) on high-quality protein digestibility.

Objective: The aim of this study was to determine the effect of black tea on the true indispensable amino acid (IAA) digestibility of whole boiled egg protein, in healthy adult humans, through use of a dual isotope tracer approach.

Protein-quality evaluation of complementary foods in Indian children.

Background: The types of food in complementary feeding of infants and young children are important for growth and development. Food protein quality, as measured by the Digestible Indispensable Amino Acid Score (DIAAS), requires the determination of true ileal digestibility of indispensable amino acids (IAAs) in children.

Objectives: First, the aim of this study was to measure the true ileal IAA digestibility of 4 (rice, finger millet, mung bean, and hen egg) commonly consumed complementary foods in children aged <2 y using the dual-isotope tracer method.

Ileal digestibility of intrinsically labeled hen's egg and meat protein determined with the dual stable isotope tracer method in Indian adults.

Background: Protein quality assessment through the Digestible Indispensable Amino Acid Score requires accurate measurements of true ileal protein and amino acid digestibility, for which a dual isotope technique was recently developed. However, the ileal digestibility of indispensable amino acids (IAA) in humans from high-quality proteins is not well known.

Objective: The aim of this study was to intrinsically label hen's egg and meat protein by the use of uniformly 2H-labeled amino acids, and to measure their true ileal indispensable amino acid (IAA) digestibility via the dual isotope method in humans.