F2,6BP restores mitochondrial genome integrity in Huntington's Disease

Area of Science:

• Neuroscience
• Mitochondrial Biology
• Genetics

Background:

• Impaired mitochondrial function and DNA damage are implicated in Huntington's disease (HD) progression.
• Polynucleotide kinase 3'-phosphatase (PNKP) activity is crucial for DNA repair but is reduced in HD.

Purpose of the Study:

• To investigate the role of fructose-2,6 bisphosphate (F2,6BP) in regulating PNKP activity and mitochondrial integrity in HD.
• To determine if F2,6BP supplementation can ameliorate HD-related pathology.

Main Methods:

• Assessed PNKP activity, F2,6BP and PFKFB3 levels in mitochondrial extracts from HD patients and mouse models.
• Investigated the effect of F2,6BP supplementation on mitochondrial function and DNA integrity in HD cells and a Drosophila model.

Main Results:

• PNKP activity was significantly decreased in HD mitochondria due to lower F2,6BP levels.
• F2,6BP acts as a cofactor for PNKP, and its supplementation restored PNKP activity.
• F2,6BP supplementation improved mitochondrial genome integrity, membrane potential, respiration, and reduced aggregate formation in HD models.

Conclusions:

• Reduced F2,6BP levels impair mitochondrial DNA repair in HD by decreasing PNKP activity.
• F2,6BP supplementation represents a potential therapeutic strategy for Huntington's disease by restoring mitochondrial function and integrity.