Sodium pyruvate improves the plasma amino acid profile in rats with L-arginine-induced acute pancreatitis.

Plasma amino acid levels are altered upon many pathological conditions including acute pancreatitis. It is unclear whether amino acids can be used as specific biomarker of acute pancreatitis severity or recovery. Development of acute pancreatitis is associated with mitochondrial dysfunction and decreased cytosolic ATP level. Sodium pyruvate is considered as a potential treatment of pancreatitis due to its ability to sustain mitochondrial oxidative and ATP-productive capacity in vitro. This study investigated the effect of sodium pyruvate on pancreatic morphology and plasma amino acid levels in rats with acute pancreatitis. Acute pancreatitis in rats was induced by administration of L-arginine (5 g/kg) Experimental treatment group received sodium pyruvate (1 g/kg) for 4 days. On day 8 of the experiment, animals were killed, blood was collected and plasma amino acid concentration was determined with high-performance liquid chromatography. Histological examination showed large areas of fibrosis in the pancreas of animals treated with L-arginine irrespectively of sodium pyruvate administration. Sodium pyruvate improved the plasma amino acid levels. Rats with acute pancreatitis had significantly lower levels of most essential and non-essential amino acids and increased glutamate and aspartate in plasma. Administration of sodium pyruvate completely or partially restored the levels of methionine, phenylalanine, tryptophan, leucine, isoleucine, aspartate, asparagine and ornithine levels, while increasing glutamine and serine to levels significantly higher than control. Plasma lysine, alanine, arginine and taurine remained unaffected in all experimental groups. Sodium pyruvate may be considered for use as a maintenance therapy in acute pancreatitis.

Modulation of the Purine Pathway for Riboflavin Production in Flavinogenic Recombinant Strain of the Yeast Candida famata.

Riboflavin (vitamin B2 ) is an indispensable nutrient for humans and animals, since it is the precursor of the essential coenzymes flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), involved in variety of metabolic reactions. Riboflavin is produced on commercial scale and is used for feed and food fortification purposes, and in medicine. Until recently, the mutant strains of the flavinogenic yeast Candida famata were used in industry for riboflavin production. Guanosine triphosphate is the immediate precursor of riboflavin synthesis. Therefore, the activation of metabolic flux toward purine nucleotide biosynthesis is a promising approach to improve riboflavin production. The phosphoribosyl pyrophosphate synthetase and phosphoribosyl pyrophosphate amidotransferase are the rate limiting enzymes in purine biosynthesis. Corresponding genes PRS3 and ADE4 from yeast Debaryomyces hansenii are modified to avoid feedback inhibition and cooverexpressed on the background of a previously constructed riboflavin overproducing strain of C. famata. Constructed strain accumulates twofold more riboflavin when compared to the parental strain.