HDL cholesterol efflux normalised to apoA-I is associated with future development of type 2 diabetes: from the CORDIOPREV trial

Effect of a Multifactorial Weight Loss Intervention on HDL Cholesterol Efflux Capacity and Immunosenescence: A Randomized Controlled Trial

OBJECTIVE

Life expectancy and obesity prevalence are increasing worldwide, leading to an increase in the prevalence of cardiovascular disease. High-density lipoprotein (HDL) functionality and immunosenescence play key roles in cardiovascular disease, longevity, and quality of aging. Both molecular hallmarks of aging are impacted by obesity and metabolic syndrome and can be modulated by lifestyle. We aimed to evaluate the effect of a lifestyle intervention focused on an energy-reduced Mediterranean diet (erMedDiet), physical activity (PA), and behavioral support on HDL cholesterol efflux capacity (CEC) and immunosenescence.

METHOD

CEC and immunosenescent T cells were determined in 60 participants from the control group (CG) and 56 from the intervention group (IG) of the PREDIMED-Plus trial at baseline and after 1 and 3 years of follow-up. PREDIMED-Plus is a randomized, controlled, parallel-group trial with an IG of erMedDiet, PA promotion, and behavioral support for weight loss and a CG of usual primary care advice. The sample included 116 volunteers from the PREDIMED-Plus-IMDEA subsample of the PREDIMED-Plus trial. Men aged 55 to 75 years and women aged 60 to 75 years with a body mass index between 27 and 40 kg/m2 and metabolic syndrome were included.

RESULTS

Participants within the IG had significantly improved CEC (2.42% and 10.69% after 1 and 3 years of follow-up) and a decreased in senescent T cell profile (-3.32% ± 12.54% and -6.74% ± 11.2%, p < 0.001, after 1 and 3 years of follow-up). Baseline obesity status impacted the response to the intervention.

CONCLUSIONS

A weight loss intervention program with erMedDiet and PA ameliorated senescence markers.

APOLIPOPROTEIN E GENE POLYMORPHISMS AND PLASMA LIPIDS IN PERSONS LIVING WITH HIV: A CROSS SECTIONAL STUDY

Background and Objective

A major modifiable risk factor for atherosclerotic cardiovascular disease is abnormalities in lipid and lipoprotein metabolism which are frequently seen in HIV as well as its treatment. Apo-E is a protein that is important in plasma lipid homeostasis and its genetic alleles have been shown to contribute to lipid abnormalities. We examined for the effect of Apo-E gene polymorphisms on plasma lipid levels in PLHIV on protease inhibitor therapy.

Methods

This was a cross-sectional study conducted among adult persons living with HIV. Lipid profile, Apo-B and Apo-A were measured in fasting plasma. Amplification and analysis of Apo-E genotypes were determined using the Seeplex Apo-E ACE genotyping kit. Differences in quantitative values were compared with non-parametric analysis methods.

Results

Eighty-four persons were recruited into the study, 75% of whom were virally suppressed. The 3 homozygous genotypes had significantly different levels of low-density lipoprotein cholesterol (LDL-C), Apolipoprotein B (Apo-B) and Apolipoprotein A1 (Apo-A1). Persons with apo ε2/ε2 had higher LDL-C compared to those with apo ε3/ε3 (3.26 (3.61) mmol/L vs. 2.76 (1.28) mmol/L, p = 0.010). Those with apo ε4/ε4 had lower Apo-A1 compared to those with apo ε3/ε3 (0.84 (0.48) g/dL vs. 1.27 (0.70) g/dL, p =0.009). Compared with the same group, the heterozygous genotype, apo ε2/ε3 had lower triglyceride levels :1.33 (0.65) mmol/ L vs. 1.86 (1.11) mmol/L, p = 0.045.

Conclusion

Polymorphisms in the Apo-E gene may have significant influences on plasma lipid and apolipoprotein levels in PLHIV on PI therapy. This may have implications for the assessment of risk for cardiovascular disease.

Asthmatic patients with high serum amyloid A have proinflammatory HDL: Implications for augmented systemic and airway inflammation

RATIONALE

Serum amyloid A (SAA) is bound to high-density lipoproteins (HDL) in blood. Although SAA is increased in the blood of patients with asthma, it is not known whether this modifies asthma severity.

OBJECTIVE

We sought to define the clinical characteristics of patients with asthma who have high SAA levels and assess whether HDL from SAA-high patients with asthma is proinflammatory.

METHODS

SAA levels in serum from subjects with and without asthma were quantified by ELISA. HDLs isolated from subjects with asthma and high SAA levels were used to stimulate human monocytes and were intravenously administered to BALB/c mice.

RESULTS

An SAA level greater than or equal to 108.8 μg/mL was defined as the threshold to identify 11% of an asthmatic cohort (n = 146) as being SAA-high. SAA-high patients with asthma were characterized by increased serum C-reactive protein, IL-6, and TNF-α; older age; and an increased prevalence of obesity and severe asthma. HDL isolated from SAA-high patients with asthma (SAA-high HDL) had an increased content of SAA as compared with HDL from SAA-low patients with asthma and induced the secretion of IL-6, IL-1β, and TNF-α from human monocytes via a formyl peptide receptor 2/ATP/P2X purinoceptor 7 axis. Intravenous administration to mice of SAA-high HDL, but not normal HDL, induced systemic inflammation and amplified allergen-induced neutrophilic airway inflammation and goblet cell metaplasia.

CONCLUSIONS

SAA-high patients with asthma are characterized by systemic inflammation, older age, and an increased prevalence of obesity and severe asthma. HDL from SAA-high patients with asthma is proinflammatory and, when intravenously administered to mice, induces systemic inflammation, and amplifies allergen-induced neutrophilic airway inflammation. This suggests that systemic inflammation induced by SAA-high HDL may augment disease severity in asthma.

Novel Insights of ANGPTL-3 on Modulating Cholesterol Efflux Capacity Induced by HDL Particle

BACKGROUND

Angiopoietin-like protein 3 (ANGPTL-3) modulates lipid metabolism and the risk of coronary artery disease (CAD), especially stable angina (SA), via suppressing lipoprotein lipase (LPL). However, whether there are other mechanisms is not elucidated yet. The current research explored the modulatory roles of ANGPTL-3 on high-density lipoprotein (HDL), which further affects atherosclerotic development.

METHODS

A total of 200 individuals were enrolled in the present study. Serum ANGPTL- 3 levels were detected via enzyme-linked immunosorbent assays (ELISA). Cholesterol efflux capacity induced by HDL particles was detected through H3-cholesterol loading THP-1 cell.

RESULTS

The serum ANGPTL-3 levels presented no significant discordance between the SA group and the non-SA group, whereas the serum ANGPTL-3 levels in type 2 diabetes mellitus (T2DM) group were significantly elevated compared with those in the non-T2DM group [428.3 (306.2 to 736.8) ng/ml vs. 298.2 (156.8 to 555.6) ng/ml, p <0.05]. Additionally, the serum ANGPTL-3 levels were elevated in patients with low TG levels compared to those in patients with high TG levels [519.9 (377.6 to 809.0) ng/ml vs. 438.7 (329.2 to 681.0) ng/ml, p <0.05]. By comparison, the individuals in the SA group and T2DM group presented decreased cholesterol efflux induced by HDL particles [SA: (12.21±2.11)% vs. (15.51±2.76)%, p <0.05; T2DM: (11.24±2.13)% vs. (14.65± 3.27)%, p <0.05]. In addition, the serum concentrations of ANGPTL-3 were inversely associated with the cholesterol efflux capacity of HDL particles (r=-0.184, p <0.05). Through regression analysis, the serum concentrations of ANGPTL-3 were found to be an independent modulator of the cholesterol efflux capacity of HDL particles (standardized β=-0.172, p <0.05).

CONCLUSION

ANGPTL-3 exhibited a negative modulatory function on cholesterol efflux capacity induced by HDL particles.

The relationship between polymorphism of insulin-like growth factor I gene and susceptibility to type 2 diabetes in Uygur population, Xinjiang, China

Background

Type 2 diabetes (T2DM) susceptibility varies among different populations and is affected by gene single nucleotide polymorphism (SNP). Insulin-like growth factor (IGF)-1 gene, which has many SNP loci, is involved in T2DM pathogenesis. However, the relationship of IGF-1 gene polymorphism with T2DM in Uyghur population is less studied.

Objective

To investigate the relationship between T2DM susceptibility and polymorphism of IGF-1 gene in Uyghur population of Xinjiang, China.

Methods

This study enrolled 220 cases (122 males (55.46%) and 98 females (44.54%); mean age of 53.40 ± 10.94 years) of T2DM patients (T2DM group) and 229 (124 males (54.15%) and 105 females (45.85%); mean age of 51.64 ± 10.48 years) healthy controls (control group). Biochemical indexes were determined. IGF-1 gene polymorphism was analyzed by SNP genotyping.

Results

The levels of TG, HDL, LDL, BUN, and Cr were statistically significant between the T2DM group and the control group. In terms of IGF-1 polymorphism, T2DM group had higher frequency of AA genotype (OR = 2.40, 95% CI = 1.19–4.84) and allele A (OR = 1.55, 95% CI = 1.17–2.06) of rs35767 loci, suggesting that rs35767 is related to the occurrence of T2DM. A total of 5 gene interaction models was obtained through analyzing the interaction of 5 SNP loci with the GMDR method. Among them, the two-factor model that included rs35767 locus and rs5742694 locus had statistical difference with a large cross-validation consistency (10/10). The combination of GG/CC, GA/AA, AA/AA, and AA/AC genotype was in high-risk group, whereas the combination of GG/AA, GG/AC, GA/AC and GA/CC genotype was in the low-risk group. The risk of T2DM in the high-risk group was 2.165 times than that of the low-risk group (OR = 2.165, 95% CI = 1.478–3.171).

Conclusion

TG, HDL, LDL, BUN, and Cr are influencing factors of T2DM in Uyghur population. The rs35767 locus of IGF-1 gene may be associated with T2DM in Uyghur population. The high-risk group composing of rs35767 locus and rs5742694 locus has a higher risk of T2DM.

The influence of high-density lipoprotein (HDL) and HDL subfractions on insulin secretion and cholesterol efflux in pancreatic derived β-cells

BACKGROUND

High-density lipoprotein (HDL) is considered a complex plasma-circulating particle with subfractions that vary in function, size, and chemical composition. We sought to test the effects of HDL, and HDL subfractions on insulin secretion and cholesterol efflux in the β-cell line MIN-6.

METHODS

We used total HDL and HDL subfractions 2a, 2b, 3a, 3b, and 3c, isolated from human plasma, to test insulin secretion under different glucose concentrations as well as insulin content and cholesterol efflux in the insulinoma MIN-6 cell line.

RESULTS

Incubation of MIN-6 cells with low glucose and total HDL increased insulin release two-fold. Meanwhile, when high glucose and HDL were used, insulin release increased more than five times. HDL subfractions 2a, 2b, 3a, 3b, and 3c elicited higher insulin secretion and cholesterol efflux than their respective controls, at both low and high glucose concentrations. The insulin content of the MIN-6 cells incubated with low glucose and any of the five HDL subclasses had a modest reduction compared with their controls. However, there were no statistically significant differences between each HDL subfraction on their capacity of eliciting insulin secretion, insulin content, or cholesterol efflux.

CONCLUSIONS

HDL can trigger insulin secretion under low, normal, and high glucose conditions. We found that all HDL subfractions exhibit very similar capacity to increase insulin secretion and cholesterol efflux. This is the first report demonstrating that HDL subfractions act both as insulin secretagogues (under low glucose) and insulin secretion enhancers (under high glucose) in the MIN-6 cell line.

Dysfunctional High-Density Lipoproteins in Type 2 Diabetes Mellitus: Molecular Mechanisms and Therapeutic Implications

High density lipoproteins (HDLs) are commonly known for their anti-atherogenic properties that include functions such as the promotion of cholesterol efflux and reverse cholesterol transport, as well as antioxidant and anti-inflammatory activities. However, because of some chronic inflammatory diseases, such as type 2 diabetes mellitus (T2DM), significant changes occur in HDLs in terms of both structure and composition. These alterations lead to the loss of HDLs' physiological functions, to transformation into dysfunctional lipoproteins, and to increased risk of cardiovascular disease (CVD). In this review, we describe the main HDL structural/functional alterations observed in T2DM and the molecular mechanisms involved in these T2DM-derived modifications. Finally, the main available therapeutic interventions targeting HDL in diabetes are discussed.

Association between cholesterol efflux capacity and peripheral artery disease in coronary heart disease patients with and without type 2 diabetes: from the CORDIOPREV study

Background

Peripheral artery disease (PAD) is recognized as a significant predictor of mortality and adverse cardiovascular outcomes in patients with coronary heart disease (CHD). In fact, coexisting PAD and CHD is strongly associated with a greater coronary event recurrence compared with either one of them alone. High-density lipoprotein (HDL)-mediated cholesterol efflux capacity (CEC) is found to be inversely associated with an increased risk of incident CHD. However, this association is not established in patients with PAD in the context of secondary prevention. In this sense, our main aim was to evaluate the association between CEC and PAD in patients with CHD and whether the concurrent presence of PAD and T2DM influences this association.

Methods

CHD patients (n = 1002) from the CORDIOPREV study were classified according to the presence or absence of PAD (ankle-brachial index, ABI ≤ 0.9 and ABI > 0.9 and < 1.4, respectively) and T2DM status. CEC was quantified by incubation of cholesterol-loaded THP-1 cells with the participants' apoB-depleted plasma was performed.

Results

The presence of PAD determined low CEC in non-T2DM and newly-diagnosed T2DM patients. Coexisting PAD and newly-diagnosed T2DM provided and additive effect providing an impaired CEC compared to non-T2DM patients with PAD. In established T2DM patients, the presence of PAD did not determine differences in CEC, compared to those without PAD, which may be restored by glucose-lowering treatment.

Conclusions

Our findings suggest an inverse relationship between CEC and PAD in CHD patients. These results support the importance of identifying underlying mechanisms of PAD, in the context of secondary prevention, that provide potential therapeutic targets, that is the case of CEC, and establishing strategies to prevent or reduce the high risk of cardiovascular events of these patients.

Trial registrationhttps://clinicaltrials.gov/ct2/show/NCT00924937. Unique Identifier: NCT00924937

High Density Lipoprotein Cholesterol Efflux Capacity and Atherosclerosis in Cardiovascular Disease: Pathophysiological Aspects and Pharmacological Perspectives

Over the years, the relationship between high-density lipoprotein (HDL) and atherosclerosis, initially highlighted by the Framingham study, has been revealed to be extremely complex, due to the multiple HDL functions involved in atheroprotection. Among them, HDL cholesterol efflux capacity (CEC), the ability of HDL to promote cell cholesterol efflux from cells, has emerged as a better predictor of cardiovascular (CV) risk compared to merely plasma HDL-cholesterol (HDL-C) levels. HDL CEC is impaired in many genetic and pathological conditions associated to high CV risk such as dyslipidemia, chronic kidney disease, diabetes, inflammatory and autoimmune diseases, endocrine disorders, etc. The present review describes the current knowledge on HDL CEC modifications in these conditions, focusing on the most recent human studies and on genetic and pathophysiologic aspects. In addition, the most relevant strategies possibly modulating HDL CEC, including lifestyle modifications, as well as nutraceutical and pharmacological interventions, will be discussed. The objective of this review is to help understanding whether, from the current evidence, HDL CEC may be considered as a valid biomarker of CV risk and a potential pharmacological target for novel therapeutic approaches.

Lipid efflux mechanisms, relation to disease and potential therapeutic aspects

Lipids are hydrophobic and amphiphilic molecules involved in diverse functions such as membrane structure, energy metabolism, immunity, and signaling. However, altered intra-cellular lipid levels or composition can lead to metabolic and inflammatory dysfunction, as well as lipotoxicity. Thus, intra-cellular lipid homeostasis is tightly regulated by multiple mechanisms. Since most peripheral cells do not catabolize cholesterol, efflux (extra-cellular transport) of cholesterol is vital for lipid homeostasis. Defective efflux contributes to atherosclerotic plaque development, impaired β-cell insulin secretion, and neuropathology. Of these, defective lipid efflux in macrophages in the arterial walls leading to foam cell and atherosclerotic plaque formation has been the most well studied, likely because a leading global cause of death is cardiovascular disease. Circulating high density lipoprotein particles play critical roles as acceptors of effluxed cellular lipids, suggesting their importance in disease etiology. We review here mechanisms and pathways that modulate lipid efflux, the role of lipid efflux in disease etiology, and therapeutic options aimed at modulating this critical process.

Human high-density lipoprotein microtranscriptome is unique and suggests an extended role in lipid metabolism

Aim: To comprehensively characterize the high-density lipoproteins (HDLs) microtranscriptome and to assess whether it is distinct from that of plasma and different between women and men. Methods: RNA was extracted from ultracentrifugation-purified HDLs and plasma from 17 healthy women and men couples, and libraries were sequenced on a HiSeq2500 platform. Results: On average, 310 ± 64 and 355 ± 31 miRNAs were detected (≥1 read per million) in HDLs and plasma, respectively. A total of 62 and 134 miRNAs were over-represented (e.g., miR-150-5p; fold change = 7.52; p_adj = 5.41 × 10^-111) and under-represented (e.g., miR-22-3p; fold change = -5.28; p_adj = 2.11 × 10^-154) in HDLs compared with plasma. These miRNAs were enriched in lipid metabolism and cellular processes-related pathways. Conclusion: HDLs exhibit a sex-independent miRNA profile distinct from that of plasma. These miRNAs may contribute to the HDLs' physiology.

Changes in Splicing Machinery Components Influence, Precede, and Early Predict the Development of Type 2 Diabetes: From the CORDIOPREV Study

Background

Type-2 diabetes mellitus (T2DM) is a major health problem with increasing incidence, which severely impacts cardiovascular disease. Because T2DM is associated with altered gene expression and aberrant splicing, we hypothesized that dysregulations in splicing machinery could precede, contribute to, and predict T2DM development.

Methods

A cohort of patients with cardiovascular disease (CORDIOPREV study) and without T2DM at baseline (at the inclusion of the study) was used (n = 215). We determined the expression of selected splicing machinery components in fasting and 4 h-postprandial peripheral blood mononuclear cells (PBMCs, obtained at baseline) from all the patients who developed T2DM during 5-years of follow-up (n = 107 incident-T2DM cases) and 108 randomly selected non-T2DM patients (controls). Serum from incident-T2DM and control patients was used to analyze in vitro the modulation of splicing machinery expression in control PBMCs from an independent cohort of healthy subjects.

Findings

Expression of key splicing machinery components (e.g. RNU2, RNU4 or RNU12) from fasting and 4 h-postprandial PBMCs of incident-T2DM patients was markedly altered compared to non-T2DM controls. Moreover, in vitro treatment of healthy individuals PBMCs with serum from incident-T2DM patients (compared to non-T2DM controls) reduced the expression of splicing machinery elements found down-regulated in incident-T2DM patients PBMCs. Finally, fasting/postprandial levels of several splicing machinery components in the PBMCs of CORDIOPREV patients were associated to higher risk of T2DM (Odds Ratio > 4) and could accurately predict (AUC > 0.85) T2DM development.

Interpretation

Our results reveal the existence of splicing machinery alterations that precede and predict T2DM development in patients with cardiovascular disease.

Fund

ISCIII, MINECO, CIBERObn.