Effects of undernutrition on glycine metabolism in the cerebellum of rats.

Undernutrition is a worldwide problem affecting millions of unborn and young children during the most vulnerable stages of brain development. Total restriction of protein during the perinatal period of life can alter the development of the mammalian fetus and have marked repercussions on development of the central nervous system (CNS). The brain is vulnerable to undernutrition with altered morphologic and biochemical maturation, leading to impaired functions. The focus of this study is to investigate [U-14C]glycine metabolism in undernourished rats submitted to pre- and postnatal protein deprivation (diet: 8% protein with and without addition of L-methionine; control group: 25% protein). Although undernutrition produced a reduction in cerebellar weight and alterations in the DNA concentration, the present study shows that glycine metabolism in this structure is partially protected because the undernourished group with L-methionine did not show modifications in glycine metabolism at all ages studied. However, L-methionine deficiency alters glycine metabolism at 7 and 21 days, but in the adult age both undernourished groups presented no differences in oxidation to CO2, conversion to lipids and incorporation into protein from glycine, compared to the control group. Copyright (c) 2004 S. Karger AG, Basel.