The article shows that skeletal muscle plays a dominant role in the catabolism of branched-chain amino acids (BCAAs; valine, leucine, and isoleucine) and the pathogenesis of their decreased concentrations in liver cirrhosis, increased concentrations in diabetes, and nonspecific alterations in disorders with signs of systemic inflammatory response syndrome (SIRS), such as burn injury and sepsis. The main role of skeletal muscle in BCAA catabolism is due to its mass and high activity of BCAA aminotransferase, which is absent in the liver. Decreased BCAA levels in liver cirrhosis are due to increased use of the BCAA as a donor of amino group to alpha-ketoglutarate for synthesis of glutamate, which in muscles acts as a substrate for ammonia detoxification to glutamine. Increased BCAA levels in diabetes are due to alterations in glycolysis, citric acid cycle, and fatty acid oxidation. Decreased glycolysis and citric cycle activity impair BCAA transamination to branched-chain keto acids (BCKAs) due to decreased supply of amino group acceptors (alpha-ketoglutarate, pyruvate, and oxaloacetate); increased fatty acid oxidation inhibits flux of BCKA through BCKA dehydrogenase due to increased supply of NADH and acyl-CoAs. Alterations in BCAA levels in disorders with SIRS are inconsistent due to contradictory effects of SIRS on muscles. Specifically, increased proteolysis and insulin resistance tend to increase BCAA levels, whereas activation of BCKA dehydrogenase and glutamine synthesis tend to decrease BCAA levels. The studies are needed to elucidate the role of alterations in BCAA metabolism and the effects of BCAA supplementation on the outcomes of specific diseases.
- MeSH
- diabetes mellitus metabolismus MeSH
- isoleucin metabolismus MeSH
- jaterní cirhóza metabolismus MeSH
- kosterní svaly metabolismus MeSH
- leucin metabolismus MeSH
- lidé MeSH
- metabolické nemoci metabolismus MeSH
- valin metabolismus MeSH
- větvené aminokyseliny metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Oxylipins of the jasmonate family are active as signals in plant responses to biotic and abiotic stresses as well as in development. Jasmonic acid (JA), its precursor cis-12-oxo-phytodienoic acid (OPDA) and the isoleucine conjugate of JA (JA-Ile) are the most prominent members. OPDA and JA-Ile have individual signalling properties in several processes and differ in their pattern of gene expression. JA-Ile, but not OPDA, is perceived by the SCFCOI1-JAZ co-receptor complex. There are, however, numerous processes and genes specifically induced by OPDA. The recently identified OPDA-Ile suggests that OPDA specific responses might be mediated upon formation of OPDA-Ile. Here, we tested OPDA-Ile-induced gene expression in wild type and JA-deficient, JA-insensitive and JA-Ile-deficient mutant background. Tests on putative conversion of OPDA-Ile during treatments revealed only negligible conversion. Expression of two OPDA-inducible genes, GRX480 and ZAT10, by OPDA-Ile could be detected in a JA-independent manner in Arabidopsis seedlings but less in flowering plants. The data suggest a bioactivity in planta of OPDA-Ile.
- MeSH
- Arabidopsis účinky léků genetika MeSH
- cyklopentany metabolismus MeSH
- ekotyp MeSH
- isoleucin analogy a deriváty metabolismus MeSH
- listy rostlin účinky léků metabolismus MeSH
- messenger RNA genetika metabolismus MeSH
- nenasycené mastné kyseliny metabolismus farmakologie MeSH
- oxylipiny metabolismus MeSH
- regulace genové exprese u rostlin účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
Expression takes place for most of the jasmonic acid (JA)-induced genes in a COI1-dependent manner via perception of its conjugate JA-Ile in the SCFCOI1-JAZ co-receptor complex. There are, however, numerous genes and processes, which are preferentially induced COI1-independently by the precursor of JA, 12-oxo-phytodienoic acid (OPDA). After recent identification of the Ile-conjugate of OPDA, OPDA-Ile, biological activity of this compound could be unequivocally proven in terms of gene expression. Any interference of OPDA, JA, or JA-Ile in OPDA-Ile-induced gene expression could be excluded by using different genetic background. The data suggest individual signaling properties of OPDA-Ile. Future studies for analysis of an SCFCOI1-JAZ co-receptor-independent route of signaling are proposed.
- MeSH
- Arabidopsis metabolismus MeSH
- cyklopentany metabolismus MeSH
- isoleucin analogy a deriváty metabolismus MeSH
- nenasycené mastné kyseliny metabolismus MeSH
- oxylipiny metabolismus MeSH
- proteiny huseníčku metabolismus MeSH
- regulátory růstu rostlin metabolismus MeSH
- signální transdukce fyziologie MeSH
- Publikační typ
- časopisecké články MeSH
Rozvětvené aminokyseliny valin, leucin, izoleucin patří mezi esenciální nutrienty, které mají větší než jen nutriční význam. Jsou důležitými mediátory a stavebními složkami v proteosyntéze, regulují hormonální funkce. Leucin je prekurzorem v syntéze cholesterolu a touto cestou hraje důležitou úlohu ve výstavbě svalové tkáně a při potlačení sarkopenie. V krátkém přehledu jsou demonstrovány starší i nová data opravňující širší využití rozvětvených aminokyselin, zejména v intenzivní péči.
The branched chain amino acids valine, leucine and isoleucine are essential nutrients with more than nutritional effects. They are important mediators and structural components in proteosynthesis and they regulate hormonal functions. Leucine is a precursor in cholesterol synthesis and as such plays an important role in muscle tissue growth and in sarcopenia suppression. Older and recent data are reviewed and support wider utilization of branched chain amino acids in intensive care.
- Klíčová slova
- rozvětvené aminokyseliny, katabolismus, beta-hydroxy-beta-methyl-butyrát, branched chain amino acids, catabolism, beta-hydroxy beta-methylbutyrate,
- MeSH
- butyráty metabolismus MeSH
- fyziologie výživy fyziologie MeSH
- isoleucin metabolismus terapeutické užití MeSH
- kritický stav terapie MeSH
- leucin farmakologie metabolismus terapeutické užití MeSH
- lidé MeSH
- nutriční podpora trendy MeSH
- péče o pacienty v kritickém stavu * trendy MeSH
- sarkopenie terapie MeSH
- valin metabolismus terapeutické užití MeSH
- větvené aminokyseliny * farmakologie metabolismus terapeutické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
- MeSH
- experimentální cirhóza jater chemicky indukované MeSH
- isoleucin metabolismus MeSH
- ketokyseliny metabolismus MeSH
- krysa rodu rattus MeSH
- leucin metabolismus MeSH
- oxidace-redukce MeSH
- techniky in vitro MeSH
- valin metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- hodnotící studie MeSH
- MeSH
- aminokyseliny metabolismus terapeutické užití MeSH
- isoleucin metabolismus terapeutické užití MeSH
- leucin metabolismus terapeutické užití MeSH
- metabolické nemoci farmakoterapie MeSH
- parenterální infuze MeSH
- parenterální výživa MeSH
- valin metabolismus terapeutické užití MeSH
- Publikační typ
- přehledy MeSH
