Cross-Classification of Human Urinary Lipidome by Sex, Age, and Body Mass Index

Abstract

Technological advancements in past decades have led to the development of integrative analytical approaches to lipidomics, such as liquid chromatography-mass spectrometry (LC/MS), and information about biogenic lipids is rapidly accumulating. Although several cohort-based studies have been conducted on the composition of urinary lipidome, the data on urinary lipids cross-classified by sex, age, and body mass index (BMI) are insufficient to screen for various abnormalities. To promote the development of urinary lipid metabolome-based diagnostic assay, we analyzed 60 urine samples from healthy white adults (young (c.a., 30 years) and old (c.a., 60 years) men/women) using LC/MS. Women had a higher urinary concentration of omega-3 12-lipoxygenase (LOX)-generated oxylipins with anti-inflammatory activity compared to men. In addition, young women showed increased abundance of poly-unsaturated fatty acids (PUFAs) and cytochrome P450 (P450)-produced oxylipins with anti-hypertensive activity compared with young men, whereas elderly women exhibited higher concentration of 5-LOX-generated anti-inflammatory oxylipins than elderly men. There were no significant differences in urinary oxylipin levels between young and old subjects or between subjects with low and high BMI. Our findings suggest that sex, but neither ages nor BMI could be a confounding factor for measuring the composition of urinary lipid metabolites in the healthy population. The information showed contribute to the development of reliable biomarker findings from urine.

Impact of Androgens on Inflammation-Related Lipid Mediator Biosynthesis in Innate Immune Cells

“…than elderly men (67). Such sex-bias was evident also in mice and rats in vivo, where female animals in zymosan-induced peritonitis, carrageenan-elicited pleurisy or experimental models of inflammation upon allergen challenge produced higher levels of LTs (23,55,56).…”

“…For example, blood or isolated monocytes and neutrophils from healthy adult women exhibited higher capacities to produce LTs upon stimulation ex vivo vs. men ( 22 , 23 , 54 ). Also, in urine samples from healthy white volunteers, higher concentrations of 5-LOX products were found in samples from elderly women than elderly men ( 67 ). Such sex-bias was evident also in mice and rats in vivo , where female animals in zymosan-induced peritonitis, carrageenan-elicited pleurisy or experimental models of inflammation upon allergen challenge produced higher levels of LTs ( 23 , 55 , 56 ).…”

Age and gender characteristics of the biochemical composition of saliva: Correlations with the composition of blood plasma

“…65,66 In general, experimental data emphasize that gender is one of the most important biological variables that significantly affect the metabolic profile of blood plasma and other biological fluids, particularly urine. [67][68][69] However, gender differences in the biochemical composition of saliva are inconclusive or controversial. 70 Additional consideration of the age group of the surveyed shows that the male plasma metabolism forms a unique cluster regardless of age, whereas for women there are two age clusters: the first is between 30 and 49 years old, the second is over 50 years old.…”

Modern Methods of Sample Preparation for the Analysis of Oxylipins in Biological Samples

“…Before target extraction, urine samples can be diluted with a buffer with an appropriate pH or with water. [115,116]. To better dissolve compounds from urine, acid or base hydrolysis is used for basic and acidic compounds, respectively.…”