Effect of starvation and refeeding on amino acid metabolism in muscle of crab Neohelice granulata previously fed protein- or carbohydrate-rich diets.
The present study assesses the effects of starvation and refeeding on 1-[(14)C]-methyl aminoisobutyric acid ((14)C-MeAIB) uptake, (14)C-total lipids, (14)CO(2) production from (14)C-glycine, (14)C-protein synthesis from (14)C-leucine and Na(+)-K(+)-ATPase activity in jaw muscle of Neohelice granulata previously maintained on a carbohydrate-rich (HC) or high-protein (HP) diet. In N. granulata the metabolic adjustments during starvation and refeeding use different pathways according to the composition of the diet previously offered to the crabs. During starvation, (14)CO(2) production from (14)C-glycine, and (14)C-protein synthesis from (14)C-leucine were reduced in HC-fed crabs. In crabs maintained on the HP or HC diet, (14)C-total lipid synthesis increased after 15 days of starvation. In crabs fed HP diet, (14)C-MeAIB uptake and Na(+)-K(+)-ATPase activity decreased in refeeding state. In crabs refeeding HC diet, (14)C-MeAIB uptake and (14)CO(2) production decreased during the refeeding. In contrast, the (14)C-protein synthesis increased after 120h of refeeding. In both dietary groups, (14)C-total lipid synthesis increased during refeeding. Changes in the carbon amino acid flux between different metabolic pathways in muscle are among the strategies used by this crab to face starvation and refeeding. Protein or carbohydrate levels in the diet administered to this crab modulate the carbon flux between the different metabolic pathways.
Department of Physiology, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, 90050-170, Porto Alegre, RS, Brazil.
Ricardo
R
Pellegrino
Tiago Leal
TL
Martins
Charles Budaszewski
CB
Pinto
Vanessa
V
Schein
Luiz Carlos
LC
Kucharski
Roselis Silveira Martins
RS
Da Silva
D000621:Aminoisobutyric Acids / Q000378:metabolism; D000818:Animals; D001692:Biological Transport; D003386:Brachyura / Q000378:metabolism* / Q000502:physiology; D002244:Carbon / Q000378:metabolism; D002245:Carbon Dioxide / Q000378:metabolism; D002250:Carbon Radioisotopes / Q000378:metabolism; D004040:Dietary Carbohydrates / Q000378:metabolism*; D004044:Dietary Proteins / Q000378:metabolism*; D004789:Enzyme Activation; D005508:Food Deprivation; D005998:Glycine / Q000378:metabolism*; D007930:Leucine / Q000378:metabolism; D050356:Lipid Metabolism; D008297:Male; D009132:Muscles / Q000378:metabolism* / Q000502:physiology; D014176:Protein Biosynthesis; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D013997:Time Factors
D000621:Aminoisobutyric Acids; D002250:Carbon Radioisotopes; D004040:Dietary Carbohydrates; D004044:Dietary Proteins; D002245:Carbon Dioxide; D002244:Carbon; D000254:Sodium-Potassium-Exchanging ATPase; D007930:Leucine; D005998:Glycine