DNA fragmentation decreased in schizophrenia but not bipolar disorder.
BACKGROUND
Apoptosis is thought to play a role in neuronal pathology in schizophrenia and bipolar disorder.


METHODS
To test this hypothesis, the Klenow method for in situ end-labeling of single-stranded DNA breaks was applied to anterior cingulate cortex from 18 healthy controls, 18 schizophrenic subjects, and 10 bipolar subjects.


RESULTS
An unexpected reduction (71%) in Klenow-positive nuclei was found in schizophrenic but not in bipolar cortexes.


CONCLUSIONS
To our knowledge to date, this is the first demonstration that there is much less DNA fragmentation in individuals with schizophrenia than in healthy controls and bipolar subjects, which raises a key question as to whether this alteration represents an adaptive or nonadaptive change in the regulation of intracellular signaling and mitochondrial oxidative pathways associated with apoptosis.
Benes
Francine M
FM
Laboratories for Structural Neuroscience, McLean Hospital, Belmont, MA 02478, USA. benesf@mclean.harvard.edu
Walsh
John
J
Bhattacharyya
Sujoy
S
Sheth
Archna
A
Berretta
Sabina
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D017209:Apoptosis / Q000235:genetics*; D001714:Bipolar Disorder / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology; D015331:Cohort Studies; D053938:DNA Fragmentation / Q000235:genetics*; D004706:Endodeoxyribonucleases / Q000235:genetics / Q000378:metabolism; D005260:Female; D006179:Gyrus Cinguli / Q000378:metabolism / Q000503:physiopathology; D006801:Humans; D020287:In Situ Nick-End Labeling; D008297:Male; D008875:Middle Aged; D018807:Polymorphism, Single-Stranded Conformational; D012559:Schizophrenia / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology
D004706:Endodeoxyribonucleases; C108945:mitochondrial oxidative damage endonuclease