Neonatal hyperglycemia induces cell death in the rat brain.

Several studies have examined neonatal diabetes, a rare disease characterized by hyperglycemia and low insulin levels that is usually diagnosed in the first 6 month of life. Recently, the effects of diabetes on the brain have received considerable attention. In addition, hyperglycemia may perturb brain function and might be associated with neuronal death in adult rats.

Intracerebroventricular administration of N-acetylaspartic acid impairs antioxidant defenses and promotes protein oxidation in cerebral cortex of rats.

N-acetylaspartic acid (NAA) is the biochemical hallmark of Canavan Disease, an inherited metabolic disease caused by deficiency of aspartoacylase activity. NAA is an immediate precursor for the enzyme-mediated biosynthesis of N-acetylaspartylglutamic acid (NAAG), whose concentration is also increased in urine and cerebrospinal fluid of patients affected by CD. This neurodegenerative disorder is clinically characterized by severe mental retardation, hypotonia and macrocephaly, and generalized tonic and clonic type seizures.

Alpha-ketoisocaproate increases the in vitro 32P incorporation into intermediate filaments in cerebral cortex of rats.

In this study we investigated the effects of alpha-ketoisocaproic (KIC), alpha-ketoisovaleric (KIV) and alpha-keto-beta-methylvaleric (KMV) acids on the phosphorylation of intermediate filament (IF) proteins of cerebral cortex of rats. Tissue slices were incubated with [32P] orthophosphate in the presence or absence of the acids. The intermediate filament enriched cytoskeletal fraction was isolated and the radioactivity incorporated into neurofilament subunits, vimentin and glial fibrillary acidic protein was measured.

Phenylalanine inhibition of the phosphorylation of cytoskeletal proteins from cerebral cortex of young rats is prevented by alanine.

Background: Phenylalanine has been considered the main responsible agent for the brain damage that occurs in phenylketonuria.

Methods And Results: In this work we studied the effect of this amino acid on the in vitro phosphorylation of cytoskeletal proteins of the cerebral cortex of rats. We observed that 2 mM phenylalanine, a concentration usually found in the plasma of phenylketonuric patients, decreased the in vitro 32P incorporation into these proteins.

Methylmalonic and propionic acids increase the in vitro incorporation of 32P into cytoskeletal proteins from cerebral cortex of young rats through NMDA glutamate receptors.

In this study we investigated the effects of methylmalonic acid (MMA) and propionic acid (PA) on the phosphorylation of cytoskeletal proteins of cerebral cortex of rats. Slices of tissue were incubated with 32P-orthophosphate in the presence or absence of glutamate, MMA, PA and ionotropic or metabotropic glutamate receptor agonists. The cytoskeletal fraction was isolated and the radioactivity incorporated into the cytoskeletal proteins was measured.