Altered Lipid Homeostasis in Mutant FUS^R521H Astrocytes from HiPSCs

Area of Science:

• Neuroscience
• Genetics
• Cell Biology

Background:

• Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder marked by motor neuron loss.
• Mutations in the fused in sarcoma (FUS) gene are linked to early-onset, rapidly progressing ALS.
• Dysfunctional glial cells, especially astrocytes, play a crucial role in ALS progression.

Purpose of the Study:

• To investigate lipid metabolism alterations in astrocytes derived from FUS-mutant human induced pluripotent stem cells (hiPSCs).
• To determine if lipid dysregulation extends to other central nervous system (CNS) cell types in FUS-ALS.

Main Methods:

• Generated FUS^R521H mutant and isogenic astrocytes from hiPSCs using inducible SOX9 overexpression.
• Performed lipidomic analysis to quantify lipid levels in mutant and control astrocytes.
• Examined lipid profiles in FUS^R521H mutant oligodendroglial progenitors and motor neurons.

Main Results:

• FUS^R521H mutant astrocytes exhibited significant deficiencies in glycerophospholipids.
• Reduced levels of phosphatidylcholine (PC) and phosphatidylinositol (PI) were prominent in mutant astrocytes.
• Decreased PC levels were also detected in FUS^R521H mutant oligodendroglial progenitors and motor neurons.

Conclusions:

• FUS-ALS is associated with widespread glycerophospholipid metabolic dysregulation across multiple CNS cell types.
• Lipid deficiencies, particularly in PC and PI, may contribute to the pathogenesis of FUS-ALS.
• Further research into lipid dysregulation is warranted for understanding and potentially treating FUS-ALS.