scholarly journals The Appetite−Suppressant and GLP-1-Stimulating Effects of Whey Proteins in Obese Subjects are Associated with Increased Circulating Levels of Specific Amino Acids

Nutrients ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 775 ◽  
Author(s):  
Antonello E. Rigamonti ◽  
Roberto Leoncini ◽  
Alessandra De Col ◽  
Sofia Tamini ◽  
Sabrina Cicolini ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Whey Proteins ◽  
Nutrient Sensing ◽  
Isoleucine Leucine ◽  
Body Weight Reduction ◽  
Appetite Suppressant ◽  
Circulating Levels

The satiating effect of whey proteins depends upon their unique amino acid composition because there is no difference when comparing whey proteins or a mix of amino acids mimicking the amino acid composition of whey proteins. The specific amino acids underlying the satiating effect of whey proteins have not been investigated to date. Aims and Methods. The aim of the present study was to evaluate the appetite-suppressant effect of an isocaloric drink containing whey proteins or maltodextrins on appetite (satiety/hunger measured by a visual analogue scale or VAS), anorexigenic gastrointestinal peptides (circulating levels of glucagon-like peptide 1 (GLP-1) and peptide tyrosine tyrosine (PYY)) and amino acids (circulating levels of single, total [TAA] and branched-chain amino acids [BCAA]) in a cohort of obese female subjects (n = 8; age: 18.4 ± 3.1 years; body mass index, BMI: 39.2 ± 4.6 kg/m2). Results. Each drink significantly increased satiety and decreased hunger, the effects being more evident with whey proteins than maltodextrins. Similarly, circulating levels of GLP-1, PYY and amino acids (TAA, BCAA and alanine, arginine, asparagine, citrulline, glutamine, hydroxyproline, isoleucine, histidine, leucine, lysine, methionine, ornithine, phenylalanine, proline, serine, threonine, tyrosine, and valine) were significantly higher with whey proteins than maltodextrins. In subjects administered whey proteins (but not maltodextrins), isoleucine, leucine, lysine, methionine, phenylalanine, proline, tyrosine, and valine were significantly correlated with hunger (negatively), satiety, and GLP-1 (positively). Conclusions. Eight specific amino acids (isoleucine, leucine, lysine, methionine, phenylalanine, proline, tyrosine, and valine) were implicated in the appetite-suppressant and GLP-1-stimulating effects of whey proteins, which may be mediated by their binding with nutrient-sensing receptors expressed by L cells within the gastrointestinal wall. The long-term satiating effect of whey proteins and the effectiveness of a supplementation with these amino acids (i.e., as a nutraceutical intervention) administered during body weight reduction programs need to be further investigated.

scholarly journals AMINO ACID COMPOSITION AND ELECTROPHORETIC PROPERTIES OF HYPERTENSIN I

1955 ◽  
Vol 102 (4) ◽  
pp. 435-440 ◽  
Author(s):  
Leonard T. Skeggs ◽  
Walton H. Marsh ◽  
Joseph R. Kahn ◽  
Norman P. Shumway
Keyword(s):  
Amino Acids ◽  
Quantitative Analysis ◽  
Amino Acid ◽  
Ion Exchange ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Isoelectric Point ◽  
Column Chromatography ◽  
Isoleucine Leucine ◽  
Ion Exchange Column

A preparation of hypertensin I was purified by countercurrent distribution and was shown to migrate as a single component in starch blocks at pH 9.3 and 4.2. It had an isoelectric point of 7.7. Quantitative analysis by ion exchange column chromatography showed eight amino acids in approximately unimolar proportion: aspartic, proline, valine, isoleucine, leucine, tyrosine, phenylalanine, and arginine. There were in addition two moles of histidine.

Amino Acid Composition of Fishery Products (II)

1950 ◽  
Vol 7d (10) ◽  
pp. 563-566 ◽  
Author(s):  
Phyllis W. Ney ◽  
Catherine P. Deas ◽  
H. L. A. Tarr
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Chum Salmon ◽  
Pink Salmon ◽  
Essential Amino Acids ◽  
Microbiological Assay ◽  
Isoleucine Leucine ◽  
Fishery Products

The essential amino acids arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, valine, tryptophane and tyrosine were determined in the following fishery products using microbiological assay technique: fish meals, stickwaters (fish solubles), condensed fish solubles, liver, commercial liver hydrolysate, frozen pink salmon viscera, chum salmon fingerlings and herring scales.

scholarly journals CHANGE OF INDICES OF THE AMINO ACID COMPOSITION OF RATS’ HEARTS AT ARTIFICIAL HYPOBIOSIS

2019 ◽  
Vol 6 ◽  
pp. 3-9
Author(s):  
Anna Umanska
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Male Rats ◽  
European Convention ◽  
Modern World ◽  
Isoleucine Leucine ◽  
Surgical Interventions ◽  
Artificial Hypobiosis

A series of unsolved questions in such sciences as: medicine, veterinary, biology still exist in the modern world. One of them is a search for new promising ways of anaesthetization, at which it would be unnecessary to use apparatuses as an “artificial heart”, “artificial ventilation of lungs” at short-term surgical interventions. Just artificial hypobiosis may become one of such methods. Main conditions for creation are a synchronous effect of such factors as hypoxia, hypercapnia, hypothermia. That is why for confirming the safety of this method in pre-clinical studies with a further perspective of using at clinical ones, it is necessary to study the mechanism of an effect and influence of the hypobiotic condition on the homeostasis of the living organism in detail. Rats are the best research object in this case. Just they have a similar physiological structure of such organs as a heart. An urgent question about changes that take place in the amino acid composition under the hypobiotic effect still be unexplained. That is why the aim of the study was to investigate amino acid changes of the rat heart under condition of artificial hypobiosis. White outbred male rats with mass 180–200 g were used in the experiments. The animals were divided in groups: control (intact) and experimental: the condition of artificial hypobiosis (first group) and 24 hours after release from artificial hypobiosis (second group). The number of animals in each group n=5. The experiments were conducted according to requirements of “The European convention about protection of vertebral animals, used with experimental or other scientific aims” (Strasbourg, France 1985), by general ethical principles of experiments with animals, approved by the First national congress of Ukraine on bioethics (2001). As a result of the conducted studies, a little decrease of several amino acids under condition of artificial hypobiosis was demonstrated. First of all, a decrease of such amino acids as aminosuccinic, glutamic, isoleucine, leucine, lysine, arginine was observed in rats’ hearths under artificial hypobiosis. There was also demonstrated an increase of the level of these amino acids in rats’ hearts after 24 hours after release from it.

scholarly journals Change of amino-acid composition of yak blood, depending on the season of the year

2019 ◽  
Vol 49 (5) ◽  
pp. 94-97
Author(s):  
В. М. Ludu
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Amino Acid Content ◽  
Essential Amino Acids ◽  
Blood Parameters ◽  
Climatic Conditions ◽  
Isoleucine Leucine ◽  
The Republic

The results of the comparative study of yak blood parameters by amino-acid composition depending on the season of the year are presented. The research was conducted in the Republic of Tuva. The object of research were adult female yaks after the fi rst or more calving. The studied animals were at the pasture in the highlands all year round. The material of the research was whole blood stabilized by heparin and yak serum. Blood was taken in spring and autumn from the jugular vein. The determination of blood biochemical parameters and the biometric processing of the results were carried out by generally accepted methods. 14 amino acids were revealed. Of these, seven are non-essential amino acids (asparagine, serine, glutamine, glycine, alanine, histidine, arginine) and seven are essential (threonine, valine, methionine, isoleucine, leucine, phenylalanine, lysine). The amino-acid content in the blood of yaks living in highlands under low partial pressure did not vary signifi cantly during the study period. The content of non-essential and essential amino acids was recorded in the ratio of 50 : 50, regardless of the season of the year. In autumn, compared to spring, serine content increased 2.43 times, asparagine –1.05 times, valine – 1.07, leucine – 1.07 times. An increase in phenylalanine in the autumn period may indicate its suffi cient content in grass eaten by yaks. Features of the interior indicators of yaks, common in the Republic of Tuva, are the result of their long year-round pasture maintenance in extreme climatic conditions of the highlands.

scholarly journals Amino acids as biomarkers of phase сomposition of gallstones

2020 ◽  
Vol 10 ◽  
pp. 22-30
Author(s):  
O. Ye. Amosova ◽  
◽  
Е. V. Mashina ◽  
S. N. Shanina
Keyword(s):  
Amino Acids ◽  
Phase Composition ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Gallstone Disease ◽  
Komi Republic ◽  
Protein Component ◽  
Isoleucine Leucine ◽  
The Difference

Gallstone disease (cholelithiasis) remains one of the most common gastroenterological diseases worldwide. The formation of gallstones has not been fully studied due to the latent course of the initial stage of gallstone disease. The composition of gallstones is diverse. Among the substances present in gallstones, the least studied is the protein component, the structural units of which are amino acids. In this connection, the main goal of the study was to identify patterns of changes in the amino acid composition of gallstones of various phase compositions. The objects of the study were 23 samples of gallstones belonging to residents of the Komi Republic. Data analysis was carried out by statistical one-dimensional and multidimensional methods. The statistical analysis, used in this work to study pathogenic formations in the human body, revealed qualitatively new, previously unremarked features of the amino acid composition of gallstones, which indicated the difference in the protein component and its relationship with the phase composition of gallstones. According to the results of cluster analysis by the contents of all amino acids, the studied gallstones were grouped into three different phase compositions of the type — cholesterol, cholesterol with a mineral component, and pigment. The Mann-Whitney and Student’s criteria established that all three types of gallstones were statistically significantly (p <0.05) pairwise different in the contents of alanine, valine, isoleucine, leucine, proline, phenylalanine, aspartic and glutamic acid. The lowest contents of the amino acids were determined in cholesterol gallstones, the highest — in pigment ones. The multidimensional method of classification trees also revealed individual amino acids phenylalanine, proline, leucine, according to which gallstones of different phase compositions were clearly separated by type. Based on the results obtained by statistical methods, special attention should be paid to Phenylalanine acid most clearly compared gallstones of different phase composition in comparison with others. The established relationships can be used to predict the type of cholelithiasis, to solve the problem of gallstones formation and metaphylaxis.

Amino acid composition of degradation-resistant peptides in extracellular rumen fluid of sheep

1993 ◽  
Vol 120 (1) ◽  
pp. 129-133 ◽  
Author(s):  
R. J. Wallace ◽  
C. J. Newbold ◽  
N. D. Watt ◽  
V. Buchan ◽  
D. S. Brown
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Rumen Fluid ◽  
Particulate Material ◽  
Exchange Chromatography ◽  
Supernatant Fluid ◽  
Isoleucine Leucine ◽  
Rotary Evaporation

SUMMARYRumen fluid was removed from four sheep 6 h after feeding, and the fluid was centrifuged to remove the micro-organisms. Perchloric acid (PCA) was added to the supernatant fluid to precipitate soluble proteins, which were again removed by centrifugation. The PCA extract was neutralized with KOH and the precipitate was removed by centrifugation. The supernatant fluid was hydrolysed with 6 MHC1 at 110 °C for 24 h, then dried by rotary evaporation, and the amino acid composition of each extract was analysed by ion-exchange chromatography. The recovery of amino acids was 98%, except for methionine, cysteine and tryptophan, which were destroyed. The recovery of amino acids from added Trypticase was 92% of the peptide mixture as amino acids. The free amino acid composition of extracellular rumen fluid was low and variable in both amount and composition (0·36, S.D. 0·49, μmol/ml). The concentration of amino acids released by acid hydrolysis of the PCA extract, presumed to be derived from peptides, was larger and its composition was less variable (1 ·02, S.D. 0·30, μmol/ml). Aspartic acid and histidine were enriched in peptides in comparison with the amino acids present in the feed or in rumen particulate material. Glycine and proline contents were higher in peptides that in particulate material. In contrast, the contents of isoleucine, leucine, tyrosine and phenylalanine tended to be lower in peptides than in the other materials. It was concluded that extracellular degradation-resistant peptides had a composition that was different to microbial protein and to the feed. The peptides appeared to be enriched for amino acids which previous studies with pure peptides had shown tend to make peptides more resistant to degradation.

scholarly journals The Amino Acid Composition of Keratins

1955 ◽  
Vol 8 (4) ◽  
pp. 537 ◽  
Author(s):  
DH Simmonds
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Merino Wool

The amino acid composition of 16-hr 6N HCI hydrolysates of three qualities of commercially classified wools has now been determined using the technique of Moore and Stein (1951). In this paper the results obtained on samples of Merino 70's and Corriedale 56's wool are compared with those previously reported for Merino wool of 64's quality. The overall pattern of the amino acid composition of the three wools is similar although small variations between the wools are observed with some of the amino acids.

scholarly journals Amino acid production in isolated rat liver mitochondria

1973 ◽  
Vol 134 (2) ◽  
pp. 431-436 ◽  
Author(s):  
W. Ferdinand ◽  
W. Bartley ◽  
V. Broomhead
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Lipid Hydroperoxide ◽  
Liver Mitochondria ◽  
Cysteic Acid ◽  
Rat Liver Mitochondria ◽  
Isolated Mitochondria ◽  
Selective Retention

Amino acid analyses of mitochondrial membranes are compared with the amino acid composition of whole mitochondria (Alberti, 1964) and found to be very similar except in the cystine content. The composition of the endogenous amino acids found in freshly prepared mitochondria has been established and shown to differ considerably from the amino acid composition of membranes or whole mitochondria. The amino acids produced during anaerobic incubation of mitochondria at pH7.4, on the other hand, resemble the membrane in composition, supporting the view that neutral proteinase activity is responsible for their appearance. Aerobic incubation produces a similar pattern of amino acids except that amino acids such as proline, serine, asparagine, glutamic acid and glutamine, which can be metabolically utilized under aerobic conditions, are present to a smaller extent. The presence of large relative concentrations of endogenous taurine, cysteic acid and oxidized glutathione and the accumulation of taurine during incubation is found. The selective retention of taurine and cysteic acid within the mitochondria is established. It is proposed that the first step in the degeneration of isolated mitochondria results from lipid hydroperoxide accumulation caused by the lack of glutathione reductase in isolated mitochondria.

scholarly journals WRAP-based nanoparticles for siRNA delivery: a SAR study and a comparison with lipid-based transfection reagents

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Karidia Konate ◽  
Emilie Josse ◽  
Milana Tasic ◽  
Karima Redjatti ◽  
Gudrun Aldrian ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Gene Silencing ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Sirna Delivery ◽  
Cell Penetrating Peptides ◽  
Sirna Transfection ◽  
Arginine Residues ◽  
Sar Study

AbstractRecently, we designed novel amphipathic cell-penetrating peptides, called WRAP, able to transfer efficiently siRNA molecules into cells. In order to gain more information about the relationship between amino acid composition, nanoparticle formation and cellular internalization of these peptides composed of only three amino acids (leucine, arginine and tryptophan), we performed a structure–activity relationship (SAR) study. First, we compared our WRAP1 and WRAP5 peptides with the C6M1 peptide also composed of the same three amino acids and showing similar behaviors in siRNA transfection. Afterwards, to further define the main determinants in the WRAP activity, we synthesized 13 new WRAP analogues harboring different modifications like the number and location of leucine and arginine residues, the relative location of tryptophan residues, as well as the role of the α-helix formation upon proline insertions within the native WRAP sequence. After having compared the ability of these peptides to form peptide-based nanoparticles (PBNs) using different biophysical methods and to induce a targeted gene silencing in cells, we established the main sequential requirements of the amino acid composition of the WRAP peptide. In addition, upon measuring the WRAP-based siRNA transfection ability into cells compared to several non-peptide transfection agents available on the markets, we confirmed that WRAP peptides induced an equivalent level of targeted gene silencing but in most of the cases with lower cell toxicity as clearly shown in clonogenic assays.

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