Which lipid class is involved in forming the myelin sheath around nerves?

Which lipid class is involved in forming the myelin sheath around nerves?

• A. Cholesterol
• B. Triglycerides
• C. Phospholipids
• D. Sphingolipids

Answer: (D)

Sphingolipids are the lipid class most associated with forming the insulating myelin sheath. Myelin is extremely lipid-rich, and the sphingolipid family—sphingomyelin plus glycosphingolipids like galactocerebroside and sulfatide—provides the dense, tightly packed membrane that creates low permeability and effective electrical insulation around axons. The sphingosine backbone and long, saturated fatty acid chains of sphingolipids promote the compact multilamellar structure of myelin, which is essential for rapid nerve conduction. While cholesterol and phospholipids are also present and contribute to membrane properties, the distinctive, high abundance of sphingolipids explains why this class is closely tied to myelin formation. Triglycerides are storage lipids and do not form the structural, insulating layers of myelin.

Sphingolipids are the lipid class most associated with forming the insulating myelin sheath. Myelin is extremely lipid-rich, and the sphingolipid family—sphingomyelin plus glycosphingolipids like galactocerebroside and sulfatide—provides the dense, tightly packed membrane that creates low permeability and effective electrical insulation around axons. The sphingosine backbone and long, saturated fatty acid chains of sphingolipids promote the compact multilamellar structure of myelin, which is essential for rapid nerve conduction. While cholesterol and phospholipids are also present and contribute to membrane properties, the distinctive, high abundance of sphingolipids explains why this class is closely tied to myelin formation. Triglycerides are storage lipids and do not form the structural, insulating layers of myelin.