Possible role of corticosterone in proteolysis, glycolytic, and amino acid metabolism in primary cultured avian myotubes incubated at high-temperature conditions

AbstractAerobic capacity is a strong predictor of longevity. With aging, aerobic capacity decreases concomitantly with changes in whole body metabolism leading to increased disease risk. To address the role of aerobic capacity, aging, and their interaction on metabolism, we utilized rat models selectively bred for low and high intrinsic aerobic capacity (LCRs/HCRs) and compared the metabolomics of serum, muscle, and white adipose tissue (WAT) at two time points: Young rats were sacrificed at 9 months of age, and old rats were sacrificed at 21 months of age. Targeted and semi-quantitative metabolomics analysis was performed on the ultra-pressure liquid chromatography tandem mass spectrometry (UPLC-MS) platform. The effects of aerobic capacity, aging, and their interaction were studied via regression analysis. Our results showed that high aerobic capacity is associated with an accumulation of isovalerylcarnitine in muscle and serum at rest, which is likely due to more efficient leucine catabolism in muscle. With aging, several amino acids were downregulated in muscle, indicating more efficient amino acid metabolism, whereas in WAT less efficient amino acid metabolism and decreased mitochondrial β-oxidation were observed. Our results further revealed that high aerobic capacity and aging interactively affect lipid metabolism in muscle and WAT, possibly combating unfavorable aging-related changes in whole body metabolism. Our results highlight the significant role of WAT metabolism for healthy aging.

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Purification and properties of glutamate-phenylpyruvate aminotransferase from the ruminal protozoan Entodinium caudatum

Australian Journal of Agricultural Research ◽

10.1071/ar04050 ◽

2004 ◽

Vol 55 (9) ◽

pp. 991

Author(s):

Md. Ruhul Amin ◽

Ryoji Onodera ◽

R. Islam Khan ◽

R. John Wallace ◽

C. Jamie Newbold

Keyword(s):

Amino Acid ◽

Amino Acid Metabolism ◽

Acid Metabolism ◽

Maximum Activity ◽

Purification And Properties ◽

Sds Page ◽

Wide Range ◽

S 100 ◽

A Cell

Entodinium species are important in catabolic protein metabolism by the mixed ruminal microbial population. This study was conducted to purify, and investigate properties of one of the enzymes involved in amino acid metabolism by Entodinium caudatum, glutamate-phenylpyruvate aminotransferase (GPA; EC 2.6.1.64). GPA was purified 74-fold from a cell-free extract by ammonium sulfate precipitation and column chromatography with phenyl-superose, DEAE-Toyopearl 650M, Sephacryl S-100 HR, and Sephadex G-100. The molecular mass of GPA was estimated by SDS–PAGE to be 65.0 kDa. The optimum pH was 6.0 and it was found to be reactive over a wide range of pH from 5.0 to 10.5. Maximum activity of GPA occurred at 45°C and the activity declined at temperatures over 55°C. GPA was stable below 60°C. Aminooxyacetate and phenylhydrazine were highly inhibitory, and SDS, EDTA, and some heavy metal ions also inhibited activity. The purification and characterisation of the enzyme will help to isolate the gene and ultimately to understand the role of GPA in both anabolic and catabolic amino acid metabolism by Entodinium caudatum.

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Amino acid metabolism in the thermophilic phototroph, Chloroflexus aurantiacus: properties and metabolic role of two l-threonine (l-serine) dehydratases

Archives of Microbiology ◽

10.1007/bf00422013 ◽

1988 ◽

Vol 149 (3) ◽

pp. 249-254 ◽

Cited By ~ 10

Author(s):

Gisela Laakmann-Ditges ◽

Jobst-Heinrich Klemme

Keyword(s):

Amino Acid ◽

Amino Acid Metabolism ◽

Acid Metabolism ◽

Chloroflexus Aurantiacus ◽

Metabolic Role

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The role of amino acid metabolism during abiotic stress release

Plant Cell & Environment ◽

10.1111/pce.13518 ◽

2019 ◽

Vol 42 (5) ◽

pp. 1630-1644 ◽

Cited By ~ 30

Author(s):

Willian Batista‐Silva ◽

Björn Heinemann ◽

Nils Rugen ◽

Adriano Nunes‐Nesi ◽

Wagner L. Araújo ◽

...

Keyword(s):

Abiotic Stress ◽

Amino Acid ◽

Amino Acid Metabolism ◽

Acid Metabolism ◽

Stress Release

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Glucagon Receptor Signaling and Glucagon Resistance

International Journal of Molecular Sciences ◽

10.3390/ijms20133314 ◽

2019 ◽

Vol 20 (13) ◽

pp. 3314 ◽

Cited By ~ 18

Author(s):

Janah ◽

Kjeldsen ◽

Galsgaard ◽

Winther-Sørensen ◽

Stojanovska ◽

...

Keyword(s):

Lipid Metabolism ◽

Amino Acid ◽

Amino Acid Metabolism ◽

Acid Metabolism ◽

Metabolic Diseases ◽

Physiological Role ◽

Glucagon Receptor ◽

Metabolomic Profiling ◽

Hepatic Fat

Hundred years after the discovery of glucagon, its biology remains enigmatic. Accurate measurement of glucagon has been essential for uncovering its pathological hypersecretion that underlies various metabolic diseases including not only diabetes and liver diseases but also cancers (glucagonomas). The suggested key role of glucagon in the development of diabetes has been termed the bihormonal hypothesis. However, studying tissue-specific knockout of the glucagon receptor has revealed that the physiological role of glucagon may extend beyond blood-glucose regulation. Decades ago, animal and human studies reported an important role of glucagon in amino acid metabolism through ureagenesis. Using modern technologies such as metabolomic profiling, knowledge about the effects of glucagon on amino acid metabolism has been expanded and the mechanisms involved further delineated. Glucagon receptor antagonists have indirectly put focus on glucagon’s potential role in lipid metabolism, as individuals treated with these antagonists showed dyslipidemia and increased hepatic fat. One emerging field in glucagon biology now seems to include the concept of hepatic glucagon resistance. Here, we discuss the roles of glucagon in glucose homeostasis, amino acid metabolism, and lipid metabolism and present speculations on the molecular pathways causing and associating with postulated hepatic glucagon resistance.

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