Sulphur Amino Acids and the Metabolic Response to Cytokines

Author(s):  
R. F. Grimble
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Benedikt Feuerecker ◽  
Philipp Biechl ◽  
Christof Seidl ◽  
Frank Bruchertseifer ◽  
Alfred Morgenstern ◽  
...  

AbstractEvaluation of treatment response is among the major challenges in modern oncology. We herein used a monoclonal antibody targeting the EGF receptor (EGFR) labelled with the alpha emitter 213Bi (213Bi-anti-EGFR-MAb). EJ28Luc (bladder) and LN18 (glioma) cancer cells, both overexpressing EGFR, were incubated for 3 h with the radioimmunoconjugate. To assess the responses in the core carbon metabolism upon this treatment, these cancer cell lines were subsequently cultivated for 18 h in the presence of [U-13C6]glucose. 13C-enrichment and isotopologue profiles of key amino acids were monitored by gas chromatography–mass spectrometry (GC/MS), in order to monitor the impacts of the radionuclide-treatment upon glucose metabolism. In comparison to untreated controls, treatment of EJ28Luc cells with 213Bi-anti-EGFR-MAb resulted in a significantly decreased incorporation of 13C from [U-13C6]glucose into alanine, aspartate, glutamate, glycine, proline and serine. In sharp contrast, the same amino acids did not display less 13C-enrichments during treatment of the LN18 cells. The data indicate early treatment response of the bladder cancer cells, but not of the glioma cells though cell lines were killed following 213Bi-anti-EGFR-MAb treatment. The pilot study shows that the 13C-labelling approach is a valid tool to assess the responsiveness of cancer cells upon radionuclide-treatment in considerable metabolic detail.


2004 ◽  
Vol 17 (1) ◽  
pp. 77-88 ◽  
Author(s):  
Thomas C. Vary ◽  
Christopher J. Lynch

Sepsis initiates a unique series of modifications in the homeostasis of N metabolism and profoundly alters the integration of inter-organ cooperatively in the overall N and energy economy of the host. The net effect of these alterations is an overall N catabolic state, which seriously compromises recovery and is semi-refractory to treatment with current therapies. These alterations lead to a functional redistribution of N (amino acids and proteins) and substrate metabolism among injured tissues and major body organs. The redistribution of amino acids and proteins results in a quantitative reordering of the usual pathways of C and N flow within and among regions of the body with a resultant depletion of the required substrates and cofactors in important organs. The metabolic response to sepsis is a highly integrated, complex series of reactions. To understand the regulation of the response to sepsis, a comprehensive, integrated analysis of the fundamental physiological relationships of key metabolic pathways and mechanisms in sepsis is essential. The catabolism of skeletal muscles, which is manifested by an increase in protein degradation and a decrease in synthesis, persists despite state-of-the-art nutritional care. Much effort has focused on the modulation of the overall amount of nutrients given to septic patients in a hope to improve efficiencies in utilisation and N economies, rather than the support of specific end-organ targets. The present review examines current understanding of the processes affected by sepsis and testable means to circumvent the sepsis-induced defects in protein synthesis in skeletal muscle through increasing provision of amino acids (leucine, glutamine, or arginine) that in turn act as nutrient signals to regulate a number of cellular processes.


Author(s):  
IVONE YURIKA MIZUBUTI ◽  
LUIZ WALDEMAR DE OLIVEIRA SOUZA ◽  
OSWALDO BIONDO JÚNIOR ◽  
ELZA IOUKO IDA

Esta pesquisa teve por objetivo investigar as propriedades químicas e cômputo químico dos aminoácidos da farinha e de concentrado protéico de feijão guandu (Cajanus cajan (L.) Millsp). A farinha apresentou composição química adequada em relação a outras leguminosas. O procedimento de extração aquosa de proteína, a partir de grãos de feijão guandu com 25,73% de proteína, permitiu a obtenção de concentrado protéico com 52,47% de proteína, em base seca, compreendendo concentração da ordem de 103,85%. O concentrado protéico de feijão guandu apresentou composição química adequada, sendo que cinzas e açúcares solúveis foram concentrados 122,17 e 21,86%, respectivamente, em relação ao grão. Os níveis de aminoácidos no concentrado protéico foram similares aos de farinha de guandu, porém, a metionina foi concentrada em 42,64%. O cômputo químico indicou que os aminoácidos limitantes primários na farinha e concentrado protéico foram os sulfurados totais. A composição química da farinha e do concentrado protéico de guandu indicou potencialidade para utilização de ambos como componentes de alimentos para seres humanos e animais. Abstract The aim of this work was the investigation of the chemical properties of Pigeon pea (Cajanus cajan) (L.) Millsp) flour and protein concentrate. The flour presented suitable chemical composition in comparison to other legumes. The water extraction procedure of protein, from Pigeon pea grains with 25,73% of protein allowed to obtain a protein concentrate with 52,47% of protein in dry basis, resulting an increase in order of 103,85%. The protein concentrate of Pigeon pea showed suitable chemical composition, having an increase of 122,17% in ashes and 21,86 % in soluble sugars in relation to the crude grain. The amino acids levels in the concentrate were similar to those in the flour, however there were an increase of 42,64% in methionine concentration. The chemical score suggest that the primary limiting amino acids in the flour and in the concentrate were the total sulphur amino acids. The chemical composition of the flour and concentrate of Pigeon pea showed perspectives of its utilization as feed components for humans and animals.


Author(s):  
Andrea L. Darling ◽  
D. Joe Millward ◽  
Susan A. Lanham-New

The present paper reviews published literature on the relationship between dietary protein and bone health. It will include arguments both for and against the anabolic and catabolic effects of dietary protein on bone health. Adequate protein intake provides the amino acids used in building and maintaining bone tissue, as well as stimulating the action of insulin-like growth factor 1, which in turn promotes bone growth and increases calcium absorption. However, the metabolism of dietary sulphur amino acids, mainly from animal protein, can lead to increased physiological acidity, which may be detrimental for bone health in the long term. Similarly, cereal foods contain dietary phytate, which in turn contains phosphate. It is known that phosphate consumption can also lead to increased physiological acidity. Therefore, cereal products may produce as much acid as do animal proteins that contain sulphur amino acids. The overall effect of dietary protein on physiological acidity, and its consequent impact on bone health, is extremely complex and somewhat controversial. The consensus is now moving towards a synthesised approach. Particularly, how anabolic and catabolic mechanisms interact; as well as how the context of the whole diet and the type of protein consumed is important.


Animals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 946
Author(s):  
Pablo Jesús Marín-García ◽  
Mari Carmen López-Luján ◽  
Luís Ródenas ◽  
Eugenio Melchor Martínez-Paredes ◽  
Enrique Blas ◽  
...  

A total of 27 experimental diets were formulated starting from the same basal mixture, with a moderate content of crude protein and digestible energy (155 g and 9.86 MJ/kg of digestible matter (DM), respectively, both estimated). The contents of lysine, sulphur amino acids and threonine were variable. The first one, close to the current recommendations (Medium, M; 8.1, 5.8 and 6.9 g/kg DM for lysine, sulphur amino acids and threonine, respectively), and two other levels were on average 15% higher (High, H; 9.4, 6.6 and 7.8 g/kg DM for lysine, sulphur amino acids and threonine, respectively) or lower (Low, L; 6.7, 4.9 and 5.7 g/kg DM for lysine, sulphur amino acids and threonine, respectively). Diets were named with three letters, indicating lysine, sulphur amino acids and threonine levels, respectively. In total, 918 weaned rabbits (28 days old) were used (34 per diet). At weaning, animals were fed ad libitum with a commercial diet until day 46, day 47 each collective cage was randomly switched to one experimental diet. At day 48, blood samples were collected at 08:00h then the animals were subjected to 10 h of fasting and a second blood sample was extracted at 21.00h. At 08:00h, Pasmatic urea nitrogen (PUN) was higher with the L level of lysine (p < 0.001), unaffected by the level of sulphur amino acids and increased with the level of threonine (p < 0.001). At 21:00h, minimum PUN was observed with the MHL diet (14.72 ± 0.661 mg/dL). Taken into account the usual recommendations (established for a diet containing 11.3 MJ DE/kg DM, and then being 0.72, 0.51 and 0.61 g/MJ DE for lysine, sulphur amino acids and threonine, respectively), these results suggest that a diet containing more lysine and sulphur amino acids per energy unit (around 0.82 and 0.67 g/MJ DE) could better fit the growing rabbit requirements, although studies on the effects of such a diet on performance and protein retention are necessary.


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