Related Experiment Video
Updated: Aug 19, 2026

Quantitative and Qualitative Method for Sphingomyelin by LC-MS Using Two Stable Isotopically Labeled Sphingomyelin Species
Published on: May 7, 2018
Sphingolipids in human lens membranes: an update on their composition and possible biological implications
M Cecilia Yappert1, Douglas Borchman
1Department of Chemistry, University of Louisville, Louisville, KY 40292, USA. mcyappert@louisville.edu
Abstract:
The unique nature of the most abundant phospholipids in human lens membranes remained overlooked until the 1990s when it was possible to discern dihydrosphingomyelins (DHSMs) from the more common sphingomyelins (SMs). Unlike in other mammalian membranes, DHSMs comprise nearly half of the phospholipids in adult human lenses. Compared to SMs with a trans double bond between carbons 4 and 5 of the sphingoid backbone, the absence of this unsaturation site in DHSMs allows the participation of the OH group on C3 in intermolecular H-bonds and leads to stronger interlipid interactions with both neighboring DHSMs and cholesterol. Phospholipid compositional changes with age and lens region observed in mammals with various life spans and lens growth rates, suggest that the highest levels of DHSMs along with the lowest amounts of phosphatidylcholines and SMs are found in lenses with the lowest growth rate, namely human lenses. The participation of phospholipid metabolites in the control of mitosis and elongation of lens cells is plausible and deserves investigation.
More Related Videos
Related Concept Videos
Fluid Mosaic Model
Membrane Lipids
Phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin are the most common phospholipids present in mammalian membranes. At physiological pH, phosphatidylserine is negatively charged, while the other three...
Asymmetric Lipid Bilayer
Phosphoinositides and PIPs
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
Assembly of the Lipid Bilayer in the ER
A large chunk of any biological membrane is composed of phospholipids. These lipids have a heterogeneous distribution across different subcellular organelles and even between...
Lipid-derived Compounds in the Human Body
Fat-soluble Vitamins
Fat-soluble vitamins, including vitamins A, D, E, and K, are required in minimal quantities, but their deficiencies can lead to severely abnormal physiological conditions. For example, vitamin A deficiency can cause night blindness, dry skin, delayed...

