Phospholipid traffic between serum-HDL-erythrocyte membrane in circadian rhythm disorders

Aim: In order to reveal the phospholipid traffic between serum-HDL-erythrocyte membrane in patients using metformin, patients with psoriasis, newly diagnosed patients with T2DM and night shift workers in four conditions selected from among the pathologies known to cause circadian rhythm disorders, the levels of proteins involved in this traffic (PLTP, LCAT, EL and sPLA2) and the phospholipid composition in three layers (serum-HDL-erythrocyte membrane) in relation to these proteins and to compare all these data with those obtained from healthy individuals. Materials and Methods: Serum PLTP, LCAT, sPLA2, EL and melatonin levels of these individuals were analyzed by ELISA method. Cortisol analysis was done by chemiluminescence method. Phospholipid analyzes in serum-HDL-erythrocyte membrane were performed by HPLC and HPTLC methods. Serum Total-C, HDL-C and TG levels were analyzed by enzymatic colorimetric method. Results: According to HPLC analysis, PC subfraction (PC4) values of all groups in the erythrocyte membrane were higher than the control. Serum LCAT, EL and PLTP levels were found to be lower in all four groups compared to the control. Conclusions: Circadian rhythm disorders led to changes in erythrocyte membrane PC composition. We believe that the mechanism of these changes may be the replacement of fatty acids with the repair processes initiated by phospholipases of phospholipids damaged as a result of oxidative stress. Analysis of erythrocyte membrane lipids can be an important biomarker in the diagnosis of circadian rhythm disorders, and analysis of the fatty acid composition of membrane phospholipids by techniques such as LC-MS/MS or GC MS/MS may be more useful.