Inositol Hexaphosphate (InsP6) Activates the HDAC1/3 Epigenetic Axis to Maintain Intestinal Barrier Function

Area of Science:

• Epigenetics
• Molecular Biology
• Biochemistry

Background:

• Histone deacetylases (HDACs) are critical regulators of gene expression with therapeutic potential in cancer.
• Understanding HDAC activation mechanisms is vital for developing targeted therapies.
• The specific role of inositol polyphosphate multikinase (IPMK) in HDAC regulation was previously unclear.

Purpose of the Study:

• To investigate the role of IPMK in the activation of HDAC1 and HDAC3.
• To elucidate the functional consequences of disrupting the IPMK-HDAC1/3 interaction on gene expression and cellular functions.
• To explore the therapeutic potential of targeting the IPMK-HDAC axis.

Main Methods:

• Utilized cell lines and mouse models with IPMK deletion or inactivated kinase activity.
• Assessed HDAC1/3 deacetylase activity and downstream gene expression changes.
• Analyzed cell and intestinal permeability, and the effect of inositol hexaphosphate (InsP6) treatment.

Main Results:

• IPMK is essential for activating HDAC1 and HDAC3 deacetylase activity.
• IPMK inactivation leads to impaired HDAC1/3 activity, altered gene expression, and increased matrix metalloproteinase (MMP) gene transcription.
• Disruption of the IPMK-HDAC1/3 axis increases cell and intestinal permeability, which is rescued by InsP6 treatment.

Conclusions:

• IPMK's kinase activity is indispensable for activating HDAC1/3.
• The IPMK-HDAC1/3 pathway critically regulates intestinal barrier function.
• Targeting IPMK offers a potential therapeutic strategy for conditions involving impaired intestinal permeability.