Pathogenic VCP mutations induce mitochondrial uncoupling and reduced ATP levels

Area of Science:

• Biochemistry
• Cell Biology
• Neuroscience

Background:

• Valosin-containing protein (VCP) is a type II AAA+ ATPase.
• VCP mutations cause IBMPFD and contribute to familial ALS.
• The precise cellular mechanisms underlying VCP-related diseases are not fully understood.

Purpose of the Study:

• To investigate the impact of pathogenic VCP mutations on cellular energy metabolism.
• To elucidate the role of VCP in mitochondrial function.

Main Methods:

• Utilized patient-derived fibroblasts with three independent pathogenic VCP mutations.
• Assessed mitochondrial membrane potential, oxygen consumption, and ATP production.

Main Results:

• VCP deficiency led to profound mitochondrial uncoupling.
• Observed decreased mitochondrial membrane potential and increased oxygen consumption.
• Demonstrated a significant reduction in cellular ATP production in VCP-deficient cells.

Conclusions:

• Pathogenic VCP mutations impair mitochondrial function, leading to energy deficits.
• Reduced ATP levels compromise cellular energy capacity, increasing vulnerability to stress like ischemia.
• These findings propose a novel mechanism for VCP mutation-associated cell death.