ALKBH8 contributes to neurological function through oxidative stress regulation.

Area of Science:

• Molecular Biology
• Neuroscience
• Biochemistry

Background:

• Transfer RNA (tRNA) modifications are crucial for protein translation and cellular function.
• AlkB homolog 8 (ALKBH8) modifies tRNA wobble uridine (U34), impacting selenoprotein translation.
• The specific in vivo roles of ALKBH8 in mammalian systems, particularly the central nervous system, are not well understood.

Purpose of the Study:

• To elucidate the biological functions of ALKBH8 in the central nervous system.
• To investigate the consequences of ALKBH8 deficiency on neural function and associated molecular mechanisms.

Main Methods:

• Utilized Alkbh8-knockout (Alkbh8-/-) mice to study ALKBH8 function.
• Assessed tRNA modification levels, including 5-methoxycarbonylmethyluridine (mcm5U).
• Conducted behavioral tests (novel object recognition, rotarod, forced swim) to evaluate neurological function.
• Performed histological analysis of brain tissue (cerebral cortex, hippocampus).
• Employed omics analyses to identify differential expression of oxidative stress-related proteins and metabolites.
• Measured mitochondrial membrane potential in neurons and glial cells.

Main Results:

• Alkbh8-/- mice exhibited reduced mcm5U levels, with partial compensation in the brain.
• Behavioral tests revealed impaired cognitive function, motor coordination, and increased depressive-like behavior in Alkbh8-/- mice.
• Histological examination showed reduced brain weight and ischemic changes in the cerebral cortex and hippocampus.
• Omics analyses identified dysregulation of oxidative stress pathways in the brains of Alkbh8-/- mice.
• Neurons and glial cells from Alkbh8-/- mice displayed reduced mitochondrial membrane potential.

Conclusions:

• ALKBH8 plays a critical role in maintaining neural function.
• ALKBH8 deficiency leads to central nervous system dysfunction, potentially mediated by oxidative stress.
• ALKBH8 is essential for regulating mitochondrial function and preventing neurodegeneration.