1. Organic personality and behavioral disorders on the base of psychopathology and brain metabolism
At rest, glucose is the primary cerebral substrate as the uptake ratio O2/glucose is close to 6.
ALNS: Astrocyte -Lactate -Neuron- -Shuttle
Glycogen brocken down in astrocytes;
Astrocytes engulfing synaptic clefts devoid of mitochondria. Lactate out of glycogen is segrated from blood-borne lactate.
Specifally for exercise, enhanced cerebral lactate transport from blood into the brain supports not only the nourishment of neurons but that of astrocytes, too.
In the pre` brain imaging area´ possible neurocognitive disorders were often diagnosed on the base of `organic impression´ and clinical criteria. But the classical concept of psychopathology was broader than that one in DSM IV TR and 5. In fact, biomarkers as MRI and/or CT results (DSM5) are established, but personality, mood changes, abulia, depression, emotional lability, even neurasthenia and histrionic behavior can possibly mask organic causes as hidden brain disturbances. The `organic etiology´ has been often underestimated and treatable causes neglected. In the 70s and 80s we predated the importance of lactate in brain metabolism not knowing the besides conceptual data. Therefore a sample of 155 patients (mean age 54y) diagnosed as organic will be reevaluated seeking to find different syndromes correlating with brain metabolism. Excluded were “brain damage” after stroke, trauma, and inflammation, obviously treatable due to metabolic or infectious conditions, seizure related disorders, full-blown delirium tremens and advanced stages of dementia. Documented data with the AMDP- rating scale system were prepared by principal and discriminant function analysis to form cluster derived groupings of patients with organic brain syndromes to correlate them with the results of cerebral rates of oxygen, glucose .
Recently, there is great evidence in:
Aerobic glycolysis participates with ca % of cerebral metabolism despite sufficient oxygen to metabolize glucose in the normal human brain at rest, increases locally during increased neuronal activity.
From in vitro and in vivo experiments lactate
is a fuel source on enhanced transport from the blood into brain and may help energetically the neurons by oxidation.
For much of the 20th century, lactate was discriminated as a dead-end waste product of glycolysis due to hypoxia as a key factor in acidosis-induced tissue damage, in brain, too.
The sample had to be divided on the base of clinical signs and symptoms in degenerative, vascular, alcohol, toxic and other etiologies. A cluster named
< organic personality and behavior> (N=52) could be discriminated from depressive (N=42), demented (N=45), and delusional patients (N=8) by principal component analysis (p<0, 0000). >>> There were significant differences (p(u) < 0,001) of the cerebral rates of O2, lactate and lactate-glucose index in per cent ranges compared with normal between groups. The etiologic impact of chronic alcoholism in this group (N=41/52) is evident, also different from 17 demented alcoholics. Treatment differences are obvious. .