Hydroxychloroquine increased cholesterol transfer to high-density lipoprotein in systemic lupus erythematosus: A possible mechanism for the reversal of atherosclerosis in the disease

Serum lipid profile in systemic lupus erythematosus

Background

Dyslipidemia presents in various autoimmune diseases, and the serum lipid profile in systemic lupus erythematosus (SLE) has not yet been clearly defined. This study aims to evaluate the level of serum lipids in patients with SLE.

Methods

A case-control study evaluated four conventional sera lipids-total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), and low-density lipoprotein (LDL)-in patients with SLE compared to healthy controls (HCs). Correlations between serum lipids and clinical characteristics were analyzed in patients with SLE. A systematic review and meta-analysis were conducted to assess the epidemiology of lipid profiles in patients with SLE, and a random-effects meta-analysis was performed for data synthesis.

Results

TC and TG were elevated significantly, and HDL decreased in patients with SLE compared to HCs. Elevated lipids were associated with progressive disease activity. TC, TG, and HDL were elevated in patients with SLE and were associated with decreased IgG, increased 24-h proteinuria, white blood cells (WBCs), and neutrophils. Decreased HDL and increased TG were associated with an increase in the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Patients with SLE who took glucocorticoids (GCs) may have experienced increases in TC and TG, while those who took hydroxychloroquine (HCQ) may have experienced increases in TC and HDL. Eleven eligible studies including the present study on associations between serum lipids and SLE were reviewed by the meta-analysis. The results demonstrated elevated TC (MD = 0.85, 95% CI 0.82 to 0.89, p < 0.00001) and TG (MD = 0.96, 95% CI 0.94 to 0.99, p < 0.00001) levels in SLE, while HDL decreased (MD = -0.19, 95% CI -0.20 to -0.17, p < 0.00001).

Conclusions

Dyslipidemia is present in SLE. There was a significant association between SLE disease activity and TC, TG, and HDL. The exact pathogenesis of metabolic disorders in SLE needs to be further addressed.

Unraveling the Pleiotropic Role of High-Density Lipoproteins (HDLs) in Autoimmune Rheumatic Diseases

Autoimmune rheumatic diseases (ARDs) exhibit an elevated incidence of cardiovascular disease (CVD). The elevation of inflammatory and immune stress accompanying ARDs contributes to atherosclerosis development and alterations in lipid metabolism and lipoprotein profile add to cardiovascular (CV) risk. The plasma concentration of high-density lipoprotein cholesterol (HDLc) is inversely related to CVD and serves as a discriminator of CV risk. However, this association is not unequivocal, and changes in HDL functionality appear to emerge as a better indicator of CV risk, albeit difficult to measure and monitor clinically. The modulation of HDLc itself can bring benefits in controlling autoimmunity and reducing ARD activity. Understanding HDL function and each peculiarity involved in ARDs enables to seek means to prevent ischemic outcomes associated with CVD, in the face of the residual CV risk persisting even with controlled disease activity and classic risk factors. By comprehending HDL's structural and functional nuances, it will be possible to develop more effective strategies to manage the evolution and outcomes of ARDs. It is also necessary to standardize diagnostic methods and establish different markers for each specific disease allowing the design of intervention strategies to restore HDL functionality, reduce residual CV, and prevent, alleviate, or even suppress ARD activity.

Systemic lupus erythematosus patients have unique changes in serum metabolic profiles across age associated with cardiometabolic risk

OBJECTIVES

Cardiovascular disease through accelerated atherosclerosis is a leading cause of mortality for patients with systemic lupus erythematosus (SLE), likely due to increased chronic inflammation and cardiometabolic defects over age. We investigated age-associated changes in metabolomic profiles of SLE patients and healthy controls (HCs).

METHODS

Serum NMR metabolomic profiles from female SLE patients (n = 164, age = 14-76) and HCs (n = 123, age = 13-72) were assessed across age by linear regression and by age group between patients/HCs (Group 1, age ≤ 25, n = 62/46; Group 2, age = 26-49, n = 50/46; Group 3, age ≥ 50, n = 52/31) using multiple t tests. The impact of inflammation, disease activity and treatments were assessed, and UK Biobank disease-wide association analysis of metabolites was performed.

RESULTS

Age-specific metabolomic profiles were identified in SLE patients vs HCs, including reduced amino acids (Group 1), increased very-low-density lipoproteins (Group 2), and increased low-density lipoproteins (Group 3). Twenty-five metabolites were significantly altered in all SLE age groups, dominated by decreased atheroprotective high-density lipoprotein (HDL) subsets, HDL-bound apolipoprotein (Apo)A1 and increased glycoprotein acetyls (GlycA). Furthermore, ApoA1 and GlycA were differentially associated with disease activity and serological measures, as well as atherosclerosis incidence and myocardial infarction mortality risk through disease-wide association. Separately, glycolysis pathway metabolites (acetone/citrate/creatinine/glycerol/lactate/pyruvate) uniquely increased with age in SLE, significantly influenced by prednisolone (increased pyruvate/lactate) and hydroxychloroquine (decreased citrate/creatinine) treatment and associated with type 1 and type 2 diabetes by disease-wide association.

CONCLUSIONS

Increasing HDL (ApoA1) levels through therapeutic/nutritional intervention, whilst maintaining low disease activity, in SLE patients from a young age could improve cardiometabolic disease outcomes. Biomarkers from the glycolytic pathway could indicate adverse metabolic effects of current therapies.

Effects of belimumab on the lipid profile in systemic lupus erythematosus patients: an observational study

This study is asked to investigate the effects of belimumab on the lipid profile in systemic lupus erythematosus (SLE) patients. Forty-one SLE patients who received at least 6 months of belimumab treatment were retrospectively analyzed. The control group consisted of 56 age- and sex-matched lupus patients not treated with belimumab. The changes in lipid profile after a 6-month treatment were compared between the two groups. Generalized estimating equation (GEE) analyses were performed to examine lipid levels longitudinally during the period and the effect of clinical response variables and medication on the lipid profile in the belimumab group. In the belimumab group, high-density lipoprotein (HDL) cholesterol levels increased significantly after the 6-month treatment (P = 0.02). After 1 month, HDL, apolipoprotein A-I (apoA-I) significantly increased by 13.8 and 11.4%, compared with baseline, respectively. After 3 months, HDL and apoA-I increased by 9.0 and 7.1%, respectively. After 6 months, HDL increased by 7.6% compared with baseline. Total cholesterol, triglycerides, low-density lipoprotein cholesterol, and apolipoprotein B did not change significantly over the course of treatment. GEE analyses indicated a significant association between HDL and disease activity indexes, such as IgG, anti-dsDNA, and complement C3. Subgroup analysis revealed significant changes in HDL only in patients who had achieved a ≥ 4-point reduction in SLEDAI-2 K after 6 months of belimumab treatment. Belimumab treatment may result in a long-term increase in HDL level in SLE patients by improving control of lupus activity. This might have beneficial effects on controlling cardiovascular risk in lupus patients. Key Points • Treatment with belimumab resulted in a significant and sustained increase in the HDL levels in SLE patients. • Significant changes in HDL were observed in lupus patients treated with belimumab who had a better clinical response.

Role of Lipoprotein Levels and Function in Atherosclerosis Associated with Autoimmune Rheumatic Diseases

Immune and inflammatory mediators in autoimmune rheumatic diseases induce modification in the activity of enzymes pivotal for lipid metabolism and promote a proatherogenic serum lipid profile. However, disturbances in low- and high-density lipoprotein composition and increased lipid oxidation also occur. Therefore, lipoprotein dysfunction causes intracellular cholesterol accumulation in macrophages, smooth muscle cells, and platelets. Overall, both plaque progression and acute cardiovascular events are promoted. Single rheumatic diseases may present a particular pattern of lipid disturbances so that standard methods to evaluate cardiovascular risk may not be accurate enough. In general, antirheumatic drugs positively affect lipid metabolism in these patients.

Hydroxychloroquine Effects on THP-1 Macrophage Cholesterol Handling: Cell Culture Studies Corresponding to the TARGET Cardiovascular Trial

Background and Objectives: Cardiovascular (CV) risk is elevated in rheumatoid arthritis (RA). RA patient plasma causes pro-atherogenic derangements in cholesterol transport leading to macrophage foam cell formation (FCF). The TARGET randomized clinical trial compares CV benefits of 2 RA drug regimens. Hydoxychloroquine (HCQ) is a key medication used in TARGET. This study examines effects of HCQ on lipid transport to elucidate mechanisms underlying TARGET outcomes and as an indicator of likely HCQ effects on atherosclerosis in RA. Materials and Methods: THP1 human macrophages were exposed to media alone, IFNγ (atherogenic cytokine), HCQ, or HCQ + IFNγ. Cholesterol efflux protein and scavenger receptor mRNA levels were quantified by qRT-PCR and corresponding protein levels were assessed by Western blot. FCF was evaluated via Oil-Red-O and fluorescent-oxidized LDL. Intracellular cholesterol and efflux were quantified with Amplex Red assay. Results: With the exception of a decrease in the efflux protein cholesterol 27-hydroxylase in the presence IFNγ at all HCQ concentrations, no significant effect on gene or protein expression was observed upon macrophage exposure to HCQ and this was reflected in the lack of change in FCF and oxidized LDL uptake. Conclusions: HCQ did not significantly affect THP1 macrophage cholesterol transport. This is consistent with TARGET, which postulates superior effects of anti-TNF agents over sulfasalazine + HCQ.