IVS I-5 (G > C) is associated with changes to the RBC membrane lipidome in response to hydroxyurea treatment in β-thalassemia patients

Abstract

The red blood cell membrane loses its integrity during hemoglobinopathies like β-thalassemia and sickle cell disease. Various mutations have been associated with β-thalassemia, the most prevalent of which is the IVS-1-5 (G > C) mutation. It is associated with poor prognosis of the disease with a dependency on transfusion. Here, we have investigated the effect of IVS mutation and the administration of hydroxyurea on the red blood cell membrane lipidome isolated from patients using a liquid chromatography coupled to tandem mass spectrometry based approach to identify changes in the red blood cell membrane lipidome of patients with/without the mutation and being/not being administered hydroxyurea. A total of 50 patients, with/without hydroxyurea treatment, were recruited and 62 lipid species were identified in all groups after statistical analyses using fold change analysis, ANOVA and lipids with higher VIP values extracted from the OPLS-DA loading plot. The presence of the IVS mutation showed altered expression levels of various lipid species as compared to non-IVS individuals, such as phosphatidylcholines, steroids, phenol lipids and fatty acids. Significant changes were though found with the administration of hydroxyurea where both the IVS and non-IVS groups showed a marked increase in complex lipids of the membrane, while a decrease was observed in those without hydroxyurea administration showing degradation of these membrane lipids. This study is the first to report changes incurred by IVS mutation and hydroxyurea administration in red blood cell membranes extracted from β-thalassemia patients. Hydroxyurea administration has been perceived to improve the lipid profile of the red blood cell membrane in both IVS and non-IVS patients.