. 2020 Dec 16;14:611393. doi: 10.3389/fnins.2020.611393

TABLE 3.

Summary of lipids and enzyme activities changes in cerebrospinal fluid (CSF) fractions.

Changes in the Supernatant Fluid Fraction
CH-NAT/CH-PAT	CH-NAT/AD	CH-PAT/AD
	The ceramide to sphingomyelin ratio is significantly is lower in CH-NAT than in AD.	PC, PC-SAFA, PC-MUFA, PC34a:0, PC36a:0, and the PC36a:1 levels are higher in CH-PAT than in AD. The ceramide to sphingomyelin ratio is significantly is lower in CH-PAT than in AD.
Changes in the nanoparticle fraction
Total sphingomyelin is lower in CH-NAT than in CH-PAT. SM(35:1), SM(36:2), and the SM(42:3) levels are lower in CH-NAT than in CH-PAT. The ceramide to sphingomyelin ratio is higher in CH-NAT than in CH-PAT.	Ceramide levels are higher in CH-NAT than in AD.	Total sphingomyelin is higher in CH-PAT than in AD. SM(34:2), SM(34:1), and SM(35:1) levels are higher in CH-PAT than in AD.
Changes in enzyme activities
	Acid sphingomyelinase activity and the acid to neutral sphingomyelinase ratio are lower in AD than in CH-NAT.	Phospholipase A₂ activity is higher in AD than in CH-PAT. Acid sphingomyelinase activity and the acid to neutral sphingomyelinase ratio are lower in AD than in CH-PAT.