Authors:James Vasta, Bernard Fried, and Joseph Sherma
HPTLC analysis has been used to compare neutral lipid profiles in the urine of humans and mice. Neutral lipids and ubiquinone were extracted from urine with chloroform-methanol, 2:1, and determined on silica gel plates with 19 lanes and a concentration zone that were developed with petroleum ether-diethyl ether-glacial acetic acid, 80:20:1. Separated zones were detected with phosphomolybdic acid reagent and quantified by visible mode slit-scanning densitometry at 610 nm. Specific detection reagents were used to confirm the identity of particular lipid classes. The studies confirmed the presence of free sterols, free fatty acids, and triacylglycerols in both human and mouse urine. Methyl esters were found in mouse but not human urine. Hydrocarbons and ubiquinone were present in both human and mouse urine, but were not quantified. Similarities in the urinary neutral lipid profiles of humans and mice suggest that mice may serve as effective models for studies of the effects of infectious and metabolic diseases in humans.
Authors:Daniel Massa, James Vasta, Bernard Fried, and Joseph Sherma
High-performance thin-layer chromatography was used to examine the phospholipid profiles in the urine of
infected mice, uninfected mice, and humans. Phospholipids were extracted from urine with chloroform-methanol, 2:1, and determined on silica gel plates with 19 lanes and a concentration zone that were developed with chloroform-methanol-water, 65:25:4. Separated zones were detected by charring with aqueous cupric sulfate reagent and quantified by visible mode slit-scanning densitometry at 370 nm. Ninhydrin spray reagent was used to confirm the presence of phosphatidylethanolamine and spiking analyses were used to confirm the identity of phosphatidylcholine in human urine. Lysophosphatidylcholine was found in human but not mouse urine. Comparison of chromatograms from the urine of infected and uninfected mice showed no qualitative or quantitative differences in the phospholipid profiles, suggesting that urinary phospholipids may not serve as biological markers for trematode infection in mice. Marked differences between the overall polar lipid profiles of mouse and human urine suggest that mice may not be useful models for humans in analyses of the effects of metabolic and infectious diseases on polar lipids.