The mGluR5 agonist CHPG enhances human oligodendrocyte differentiation

Area of Science:

• Neuroscience
• Cell Biology
• Regenerative Medicine

Background:

• Previous studies in mice showed the mGluR5 agonist CHPG promotes myelin repair by acting on astrocytes.
• The effect of CHPG on human oligodendrocytes and its underlying mechanisms were previously unclear.

Purpose of the Study:

• To investigate the effects of CHPG on human oligodendrocytes (OLs) and oligodendrocyte precursor cells (OPCs).
• To determine the cellular localization of mGluR5 in human OLs and OPCs.
• To explore the potential of CHPG as a therapeutic agent for demyelinating diseases like multiple sclerosis (MS).

Main Methods:

• Cultured human induced pluripotent stem cell (hiPSC)-derived oligodendrocytes and primary human fetal oligodendrocytes were treated with CHPG.
• mGluR5 expression was analyzed in human oligodendrocytes, OPCs, and astrocytes.
• Postmortem brain tissue from individuals with chronic active MS and healthy controls was analyzed for mGluR5 expression.

Main Results:

• CHPG increased the proportion of mature, myelin basic protein-positive (MBP+) oligodendrocytes without affecting cell survival.
• CHPG enhanced the proliferation of oligodendrocyte precursor cells (OPCs) and promoted their differentiation into mature oligodendrocytes.
• In humans, mGluR5 is expressed on OPCs and immature oligodendrocytes, not astrocytes, contrasting with mouse models.
• MS patient tissues showed elevated mGluR5 mRNA expression in astrocytes within demyelinated white matter.

Conclusions:

• CHPG promotes human OPC differentiation and oligodendrocyte maturation via a mechanism distinct from that observed in mice.
• Astrocytes in MS pathology exhibit dynamic upregulation of mGluR5, suggesting a role in disease progression.
• These findings highlight CHPG's potential for myelin repair strategies in human demyelinating diseases.