Altered Lipoprotein Function and Metabolic Signatures in Relapsing–Remitting Multiple Sclerosis
Multiple Sclerosis (MS) is a complex immune-mediated disorder characterized by inflammation, demyelination, and neurodegeneration within the central nervous system. Although the immunological mechanisms of MS have been extensively studied, emerging evidence suggests that metabolic factors—particularly lipid metabolism—also influence disease pathophysiology. Lipoproteins, which transport cholesterol and triglycerides in circulation, play important roles not only in lipid homeostasis but also in immune regulation. The study published in Scientific Reports investigates whether alterations in lipoprotein composition and functionality occur in MS patients and whether these changes are associated with disease subtype and metabolic status.
Study Objective and Experimental Design
The primary objective of the study was to characterize the lipoprotein profile of patients with relapsing–remitting MS (RRMS) and progressive MS using advanced analytical techniques. Researchers applied nuclear magnetic resonance (NMR) spectroscopy to quantify lipoprotein particle size and concentration in serum samples. The study cohort included individuals with RRMS, patients with progressive MS, and healthy control subjects. By comparing these groups, the investigators aimed to determine whether lipoprotein abnormalities are associated specifically with the relapsing–remitting stage of the disease and whether body mass index (BMI) influences these metabolic alterations.
Lipoprotein Particle Changes in RRMS
The analysis revealed that patients with RRMS displayed distinct lipoprotein abnormalities compared with both progressive MS patients and healthy controls. Notably, RRMS patients exhibited smaller low-density lipoprotein (LDL) particles. Small LDL particles are considered more metabolically active and potentially more atherogenic than larger LDL particles. The presence of these altered LDL characteristics suggests that lipid metabolism may be substantially modified during the inflammatory phase of MS. These findings support the hypothesis that systemic metabolic changes accompany immune dysregulation in neuroinflammatory disorders.
Influence of Body Mass Index on Lipoprotein Alterations
A particularly striking observation emerged when the researchers stratified RRMS patients according to body mass index. Individuals with relatively low BMI (≤23 kg/m²) demonstrated more pronounced lipoprotein abnormalities. This subgroup exhibited elevated levels of small high-density lipoprotein (HDL) particles and increased concentrations of triglyceride-rich very low-density lipoproteins (VLDL). Additionally, these patients showed a higher lipoprotein insulin resistance (LP-IR) index, indicating metabolic disturbances related to insulin sensitivity. These results suggest that metabolic alterations in MS may not simply reflect obesity-related dyslipidemia but may also occur in patients with relatively low body weight.
Functional Impairment of HDL Particles
Beyond quantitative changes, the study also investigated the functional properties of HDL particles. HDL is traditionally regarded as protective due to its role in reverse cholesterol transport and anti-inflammatory signaling. However, the investigators found that HDL from RRMS patients exhibited reduced capacity to promote cholesterol efflux via the ATP-binding cassette transporter G1 (ABCG1). This mechanism is essential for removing excess cholesterol from immune cells such as macrophages. A reduction in cholesterol efflux capacity implies that HDL in RRMS may lose part of its protective functionality.
Impact on Immune Regulation
The researchers further demonstrated that HDL from RRMS patients was less effective at suppressing inflammatory activity in human monocytes. This diminished anti-inflammatory capacity indicates that altered lipoproteins may actively contribute to immune dysregulation rather than merely reflect systemic metabolic changes. The study also detected modifications in apolipoprotein A-I (ApoA-I), the principal protein component of HDL particles. Structural changes in ApoA-I may partly explain the impaired functional properties of HDL observed in the patient cohort.
Implications for Disease Progression and Future Research
Collectively, these findings suggest that both the composition and functionality of circulating lipoproteins are altered in RRMS, particularly among patients with lower BMI. Such metabolic disturbances may influence immune cell behavior and inflammatory pathways, potentially contributing to disease progression. The results highlight the importance of integrating metabolic profiling into the study of neuroinflammatory diseases. Future research may explore whether targeting lipoprotein metabolism—either through pharmacological intervention or lifestyle modification—could represent a novel therapeutic strategy for managing multiple sclerosis.
Disclaimer: This blog post is based on the provided research article and is intended for informational purposes only. It is not intended to provide medical advice. Please consult with a healthcare professional for any health concerns.
References:
Jorissen, W., Wouters, E., Bogie, J. et al. Relapsing-remitting multiple sclerosis patients display an altered lipoprotein profile with dysfunctional HDL. Sci Rep 7, 43410 (2017). https://doi.org/10.1038/srep43410
