Plasma dihydroceramide species associate with waist circumference in Mexican American families.
OBJECTIVE
Waist circumference (WC), the clinical marker of central obesity, is gaining popularity as a screening tool for type 2 diabetes (T2D). While there is epidemiologic evidence favoring the WC-T2D association, its biological substantiation is generally weak. Our objective was to determine the independent association of plasma lipid repertoire with WC.


METHODS
Samples and data from the San Antonio Family Heart Study of 1208 Mexican Americans from 42 extended families were used. Association of plasma lipidomic profiles with the cross-sectionally assessed WC was determined. Plasma lipidomic profiling entailed liquid chromatography with mass spectrometry. Statistical analyses included multivariable polygenic regression models and bivariate trait analyses using the SOLAR software.


RESULTS
After adjusting for age and sex interactions, body mass index, homeostasis model of assessment-insulin resistance, total cholesterol, triglycerides, high density lipoproteins and use of lipid lowering drugs, dihydroceramides as a class were associated with WC. Dihydroceramide species 18:0, 20:0, 22:0, and 24:1 were significantly associated and genetically correlated with WC. Two sphingomyelin species (31:1 and 41:1) were also associated with WC.


CONCLUSIONS
Plasma dihydroceramide levels independently associate with WC. Thus, high resolution plasma lipidomic studies can provide further credence to the biological underpinnings of the association of WC with T2D.
Department of Genetics, Texas Biomedical Research Institute, San Antonio, Texas, USA.
Manju
M
Mamtani
Peter J
PJ
Meikle
Hemant
H
Kulkarni
Jacquelyn M
JM
Weir
Christopher K
CK
Barlow
Jeremy B
JB
Jowett
Claire
C
Bellis
Thomas D
TD
Dyer
Laura
L
Almasy
Michael C
MC
Mahaney
Ravindranath
R
Duggirala
Anthony G
AG
Comuzzie
John
J
Blangero
Joanne E
JE
Curran
D000328:Adult; D001786:Blood Glucose; D002318:Cardiovascular Diseases / Q000097:blood / Q000208:ethnology; D002518:Ceramides / Q000097:blood*; D002784:Cholesterol / Q000097:blood; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000208:ethnology*; D006801:Humans; D008297:Male; D017058:Mexican Americans; D008875:Middle Aged; D015999:Multivariate Analysis; D009765:Obesity / Q000097:blood / Q000208:ethnology*; D015995:Prevalence; D011795:Surveys and Questionnaires; D013781:Texas / Q000453:epidemiology; D014280:Triglycerides / Q000097:blood; D055105:Waist Circumference; D055815:Young Adult
D001786:Blood Glucose; D002518:Ceramides; D014280:Triglycerides; C109343:dihydroceramide; D002784:Cholesterol