Sphingolipid serum profiling in vitamin D deficient and dyslipidemic obese dimorphic adults

Nasser M Al-Daghri,Pietro Barbacini,Cristian Ricci,Mario Clerici,Hannah Asare,Franca Rosa Guerini,Daniele Capitanio,Majed S Alokail,Enrica Torretta,Cecilia Gelfi,Shaun B Sabico

doi:10.1038/s41598-019-53122-4

Abstract

Recent studies on Saudi Arabians indicate a prevalence of dyslipidemia and vitamin D deficiency (25(OH)D) in both normal weight and obese subjects. In the present study the sphingolipid pattern was investigated in 23 normolipidemic normal weight (NW), 46 vitamin D deficient dyslipidemic normal weight (-vitDNW) and 60 vitamin D deficient dyslipidemic obese (-vitDO) men and women by HPTLC-primuline profiling and LC-MS analyses. Results indicate higher levels of total ceramide (Cer) and dihydroceramide (dhCers C18–22) and lower levels of total sphingomyelins (SMs) and dihydrosphingomyelin (dhSM) not only in -vitDO subjects compared to NW, but also in –vitDNW individuals. A dependency on body mass index (BMI) was observed analyzing specific Cer acyl chains levels. Lower levels of C20 and 24 were observed in men and C24.2 in women, respectively. Furthermore, LC-MS analyses display dimorphic changes in NW, -vitDNW and –vitDO subjects. In conclusion, LC-MS data identify the independency of the axis high Cers, dhCers and SMs from obesity per se. Furthermore, it indicates that long chains Cers levels are specific target of weight gain and that circulating Cer and SM levels are linked to sexual dimorphism status and can contribute to predict obese related co-morbidities in men and women.

Highlights

Recent studies on Saudi Arabians indicate a prevalence of dyslipidemia and vitamin D deficiency (25(OH)D) in both normal weight and obese subjects
Serum samples were collected from 23 normolipidemic normal weight (NW) controls (M/F-15/8), 46 vitamin D deficient dyslipidemic (HDL < 1 mmol/L; TG > 2.3 mmol/L) normal weight (-vitDNW) subjects (M/F-23/23) and from 60 vitamin D deficient dyslipidemic obese (-vitDO) subjects (M/F-25/35)
Gender and age composition were homogeneous across groups composed of normal weight and obese subjects (U-test p-value = 0.64, χ2 p-value = 0.15 for age and gender respectively). -vitDNW subjects were characterized by dyslipidemia, with lower levels of high density lipoprotein-CHOL (HDL) and higher levels of TRG and total cholesterol compared to NW (U-test p-value < 0.001 for HDL, TRG and total cholesterol), and with higher levels of TRG and lower levels of HDL compared to -vitDO (U-test p-value = 0.019 and 0.006 for HDL and TRG respectively)

Summary

Introduction

Recent studies on Saudi Arabians indicate a prevalence of dyslipidemia and vitamin D deficiency (25(OH)D) in both normal weight and obese subjects. LC-MS data identify the independency of the axis high Cers, dhCers and SMs from obesity per se It indicates that long chains Cers levels are specific target of weight gain and that circulating Cer and SM levels are linked to sexual dimorphism status and can contribute to predict obese related co-morbidities in men and women. Low plasma levels of vitamin D have been associated with obesity-related health complications, such as insulin resistance, type 2 diabetes and dyslipidemia[7,8,9]. A recent differential proteomic study of sera of obese men and women from Saudi Arabia, in whom low vitamin D concentrations were present, identified a number of proteins that are differentially expressed in obese compared to lean weight people; these proteins belong to different pathways, including lipid metabolism, vitamin D function and immunity/inflammation[10]. It has been described that sphingolipid (SL) concentration, in association with adiponectin, IL-6 and insulin resistance, contributes to sexual dimorphism of the adipose tissue distribution in humans[19]

Methods

Results

Conclusion