A method for HDAC activity screening in postmortem human brain. A proof-of-concept study with antipsychotics

Area of Science:

• Neuroscience
• Biochemistry
• Pharmacology

Background:

• Histone deacetylase (HDAC) activity is dysregulated in various brain disorders.
• Antipsychotic drugs (APs) are used to treat schizophrenia, but their impact on brain HDAC activity is unclear.

Purpose of the Study:

• To optimize and characterize a reliable assay for measuring HDAC activity in postmortem human brain samples.
• To investigate the effect of APs on HDAC activity in the brains of schizophrenia subjects.

Main Methods:

• Developed and validated a cost-efficient HDAC activity assay using Boc-Lys(Ac)-AMC substrate.
• Characterized assay parameters including subcellular fraction and protein concentration.
• Utilized the assay for enzyme kinetics and screening of HDAC inhibitors (HDACis).
• Assessed the effect of APs on class I HDAC activity in postmortem human brain and rat models.

Main Results:

• The optimized assay demonstrated reliability and detected class I HDAC activity, with IC50 values consistent with prior research.
• Inhibition studies confirmed the assay's ability to identify class I HDAC activity.
• No modulation of class I HDAC activity was observed in postmortem human brain samples treated with APs.
• Enzyme kinetic studies in rats treated with APs also showed no effect on class I HDAC activity.

Conclusions:

• An optimized and validated assay for measuring HDAC activity in postmortem human brain samples was successfully developed.
• Antipsychotic drugs were found to have no modulatory effect on class I HDAC activity in the studied samples.