Changes in puromycin-sensitive aminopeptidases in postmortem schizophrenic brain regions

Area of Science:

• Neuroscience
• Biochemistry
• Psychiatry

Background:

• Puromycin-sensitive aminopeptidase (PSA) is an enzyme found in human brain tissues.
• Previous research has not fully elucidated the role of specific PSA variants in psychiatric disorders like schizophrenia.

Purpose of the Study:

• To investigate the distribution of puromycin-sensitive aminopeptidase (PSA) in human brain regions.
• To examine the potential role of PSA in schizophrenia by comparing its distribution in schizophrenic and control brains.

Main Methods:

• Western immunoblot analysis was used to quantify PSA antigens in well-defined human brain areas.
• Samples were obtained from suicide victims (schizophrenia group, n=13) and myocardial infarction victims (control group, n=12).
• Two major PSA antigens, PSA-100 (with peptidase activity) and PSA-170 (without activity), were compared.

Main Results:

• PSA-100 was present in all studied brain regions, with higher levels in control brains compared to schizophrenic brains.
• PSA-170 was predominantly found in schizophrenic brains, with significantly higher levels and broader distribution than in control brains.
• The presence of PSA-170 was not attributed to neuroleptic treatment or postmortem proteolysis.

Conclusions:

• The distribution and increased amounts of PSA-170 are largely restricted to brain areas affected by schizophrenia.
• PSA-170 represents a potential biomarker or has a specific role in the pathophysiology of schizophrenia.
• Further research is warranted to determine the functional significance of PSA-170 in schizophrenia.