Proteasome mutations associated with CANDLE syndrome cause altered neuronal development by dysregulating polyamine...

Area of Science:

• Neuroscience
• Genetics
• Developmental Biology

Background:

• Loss-of-function mutations in proteasome components, like PSMB8, cause diseases including CANDLE syndrome.
• CANDLE syndrome is associated with neurocognitive deficits, suggesting proteasome impact on neuronal development.
• The 20S proteasome is crucial for cellular protein homeostasis.

Purpose of the Study:

• To investigate the impact of proteasome dysfunction on neuronal development using cerebral organoids.
• To identify molecular mechanisms underlying neurodevelopmental deficits in CANDLE syndrome.
• To explore potential therapeutic targets for CNS manifestations of proteasome-related disorders.

Main Methods:

• Generation of cerebral organoids (COs) from induced pluripotent stem cells (iPSCs) of CANDLE patients and healthy controls.
• Comparative analysis of neuronal development and maturation in CANDLE and control COs.
• Measurement of polyamine levels and Ornithine decarboxylase (ODC) activity in COs and patient cerebrospinal fluid (CSF).
• Pharmacological inhibition of ODC to assess its effect on polyamine levels and neuronal maturation.

Main Results:

• CANDLE patient-derived COs showed impaired neuronal development and maturation compared to controls.
• Elevated polyamine levels were observed in CANDLE COs and patient CSF.
• Increased Ornithine decarboxylase (ODC) activity was found in neurons from CANDLE COs.
• Inhibition of ODC normalized polyamine levels and rescued neuronal maturation defects in CANDLE COs.

Conclusions:

• Proteasome dysfunction in CANDLE syndrome leads to impaired neuronal development via polyamine overproduction.
• Dysregulation of Ornithine decarboxylase (ODC) is a key mechanism linking proteasome defects to neurodevelopmental issues.
• Targeting ODC represents a potential therapeutic strategy for neurological complications in proteasome-related disorders.