1 - Development of energy metabolism
In addition to early myelinization, development of
other metabolic processes in the inferior colliculi
precedes those in other parts of the brain. Chugani
et al. (1991) used the deoxyglucose method to
examine brain maturation in cats, and found the
highest rate of metabolism at every stage of
development in the inferior colliculus [1]. They also
found that the cerebral metabolism of developing cats
exceeds that of adult animals, and suggested that the
decline to adult metabolic levels may result from
selective elimination of surplus neurons.
Hypermetabolism in the brain during development
may also support production of trophic factors that
stimulate growth in later-maturing areas. Chugani et
al. (1998) pointed out that high metabolic rates in
young animals provide a period in which recovery
from injuries can take place [2]. Megencephaly has
been reported in some autistic individuals [3]. Could
this then be the result of unchecked growth as part of
a recovery process from perinatal damage?
Hovda et al. (1992) found cytochrome oxidase activity
in developing cats is high in the same brain areas that
have high rates of glucose uptake [4]. They also
found that maturation of the cytochrome oxidase
system is complete one to two weeks before glucose
uptake reaches its highest levels, and suggested a
necessity for the cytochrome oxidase system to be
functional first. Otherwise, glucose would undergo
anaerobic metabolism, producing lactic acid, which
can lead to cell death. This represents one possible
disruption of development that could lead to brain
damage early in life.
Nehlig (1996) investigated development of glucose
and fat metabolism in the brain of developing rats and
found an early dependence on fat metabolism, which
declined as capability to metabolize glucose matured.
This is one of several studies of development of
cerebral circulation and energy metabolism by Nehlig
and colleagues (Nehlig et al. 1989, 1991, 1993, Bilger
et al. 1992). Nehlig (1997) has compared data from
rat and human research on maturation, which support
the relevance of animal studies to human
development.
- Chugani HT et al. (1991)
Metabolic maturation of the
brain: a study of local
cerebral glucose utilization in
the developing cat.
- Chugani HT (1998) A critical
period of brain development:
studies of cerebral glucose
utilization with PET.
Preventative Medicine 27:184-
188.
- Bailey A et al. (1998) A
clinicopathological study of
autism.
- Courchesne E et al. (2003)
Evidence of brain overgrowth
in the first year of life in
autism.
- McCaffery P, Deutsch CK
(2005) Macrocephaly and the
control of brain growth in
autistic disorders.
- Hovda DA et al. (1992)
Maturation of cerebral
oxidative metabolism in the
cat: a cytochrome oxidase
histochemistry study.
- Nehlig A (1996) Respective
roles of glucose and ketone
bodies as substrates for
cerebral energy metabolism
in the suckling rat.
- Nehlig A et al. (1989)
Postnatal changes in local
cerebral blood flow
measured by the quantitative
autoradiographic [14C]
iodoantipyrine technique in
freely moving rats.
- Bilger A, Nehlig A. (1993)
Regional cerebral blood flow
response to acute hypoxia
changes with postnatal age
in the rat.
- Nehlig A et al. (1995)
Mapping of cerebral blood
flow changes during
audiogenic seizures in
Wistar rats: effect of kindling.
- Nehlig A et al. (1998) Local
cerebral glucose utilization in
adult and immature GAERS.
- Nehlig A. (1997) Cerebral
energy metabolism, glucose
transport and blood flow:
changes with maturation and
adaptation to
hypoglycaemia.
- Chugani HT, Hovda DA, Villablanca JR, Phelps ME, Xu, W-F (1991) Metabolic maturation of
the brain: a study of local cerebral glucose utilization in the developing cat. Journal of Cerebral
Blood Flow and Metabolism 11:35-47.
- Chugani HT (1998) A critical period of brain development: studies of cerebral glucose
utilization with PET. Preventative Medicine 27:184-188.
- Bailey A, Luthert P, Dean A, Harding B, Janota I, Montgomery M, Rutter M, Lantos P (1998) A
clinicopathological study of autism. Brain 121:889-905.
- Courchesne E, Carper R, Akshoomoff N. Evidence of brain overgrowth in the first year of life in
autism. JAMA. 2003 Jul 16;290(3):337-44.
- McCaffery P, Deutsch CK.Macrocephaly and the control of brain growth in autistic disorders.
Prog Neurobiol. 2005 Sep-Oct;77(1-2):38-56.
- Hovda DA, Chugani HT, Villablanca JR, Badie B, Sutton RL (1992) Maturation of cerebral
oxidative metabolism in the cat: a cytochrome oxidase histochemistry study. Journal of
Cerebral Blood Flow and Metabolism 12:1039-1048.
- Nehlig A (1996) Respective roles of glucose and ketone bodies as substrates for cerebral
energy metabolism in the suckling rat. Developmental Neuroscience 18:426-433.
- Nehlig A, Pereira de Vasconcelos A, Boyet S (1989) Postnatal changes in local cerebral
blood flow measured by the quantitative autoradiographic [14C]iodoantipyrine technique in
freely moving rats. Journal of Cerebral Blood Flow and Metabolism 9:579-588.
- Bilger A, Nehlig A. (1993) Regional cerebral blood flow response to acute hypoxia changes
with postnatal age in the rat. Brain Res Dev Brain Res. 1993 Dec 17;76(2):197-205.
- Nehlig A, Vergnes M, Hirsch E, Boyet S, Koziel V, Marescaux C (1995) Mapping of cerebral
blood flow changes during audiogenic seizures in Wistar rats: effect of kindling. Journal of
Cerebral Blood flow and Metabolism 15:259-269.
- Nehlig A, Vergnes M, Boyet S, Marescaux C (1998) Local cerebral glucose utilization in adult
and immature GAERS. Epilepsy Research 32:206-12.
- Nehlig A. (1997) Cerebral energy metabolism, glucose transport and blood flow: changes
with maturation and adaptation to hypoglycaemia. Diabetes Metab. 1997 Feb;23(1):18-29.