High density lipoprotein and metabolic disease: Potential benefits of restoring its functional properties

A Study on Multiple Facets of Apolipoprotein A1 Milano

For several strategies formulated to prevent atherosclerosis, Apolipoprotein A1 Milano (ApoA1M) remains a prime target. ApoA1M has been reported to have greater efficiency in reducing the incidence of coronary artery diseases. Furthermore, recombinant ApoA1M based mimetic peptide exhibits comparatively greater atheroprotective potential, offers a hope in reducing the burden of atherosclerosis in in vivo model system. The aim of this review is to emphasize on some of the observed ApoA1M structural and functional effects that are clinically and therapeutically meaningful that might converge on the basic role of ApoA1M in reducing the chances of glycation assisted ailments in diabetes. We also hypothesize that the nonenzymatic glycation prone arginine amino acid of ApoA1 gets replaced with cysteine residue and the rate of ApoA1 glycation may decrease due to change substitution of amino acid. Therefore, to circumvent the effect of ApoA1M glycation, the related mechanism should be explored at the cellular and functional levels, especially in respective experimental disease model in vivo.

Therapeutic mechanism of Curcuma aromatica Salisb. rhizome against coronary heart disease based on integrated network pharmacology, pharmacological evaluation and lipidomics

Curcuma aromatica Salisb. rhizome (CASR) has multifunctional characteristics worldwide and a long history of use as a botanical drug with. Currently, it is often used clinically to treat coronary heart disease (CHD) caused by blood stasis syndrome. However, the therapeutic mechanism of CASR in the treatment of CHD remains poorly understood. In study, the main chemical constituents of CASR were analyzed using UPLC-Q-TOF-MS/MS. Then, its potential therapeutic mechanism against CHD was predicted. Subsequently, pharmacological evaluation was performed using CHD rat model. Finally, a lipidomics approach was applied to explore the different lipid metabolites to verify the regulation of CASR on lipid metabolism disorders in CHD. A total of 35 compounds was identified from CASR. Seventeen active components and 51 potential targets related to CHD were screened by network pharmacology, involving 13 key pathways. In vivo experiments showed that CASR could significantly improve myocardial infarction, blood stasis, and blood lipid levels and regulate the PI3K/AKT/mTOR signaling pathway in CHD rats. Lipidomics further showed that CASR could regulate abnormal sphingolipid, glycerophospholipid, and glycerolipid metabolism in CHD rats. The therapeutic mechanism of CASR against CHD was initially elucidated and included the regulation of lipid metabolism. Its effects may be attributed to active ingredients, such as curzerene, isoprocurcumenol, and (+)-curcumenol. This study reveals the characteristics of multi-component and multi-pathway of CASR in the treatment of CHD, which provides a basis for the follow-up development and utilization of CASR.

Impact of sports participation on components of metabolic syndrome in adolescents: ABCD growth study

OBJECTIVES

This study aimed to analyze the impact of sports participation (12 months of practice) on the components of metabolic syndrome (MetS) in both sexes.

METHODS

This is an observational longitudinal study, a part of which is entitled "Analysis of Behaviors of Children During Growth" (ABCD Growth Study), Presidente Prudente, São Paulo, Brazil. The sample was composed of 171 adolescents (112 boys and 59 girls), divided into non-sports and sports groups. High-density lipoprotein-cholesterol (HDL-c), triglycerides, and glucose were analyzed by the colorimetric method of dry chemistry and processed biochemically. Systolic blood pressure and diastolic blood pressure were measured using an automatic device. Body fat was estimated using a densitometry scanner.

RESULTS

Adolescents who practiced sports were younger (p-value=0.001) and had a lower peak height velocity (p-value=0.001) than the non-sports group. The differences (Δ) after 12 months were of greater magnitude for the sports group when compared to the non-sports group (p-value=0.013), glucose (moderate magnitude in favor of the sports group; p-value=0.001), HDL-c (small magnitude in favor of the sports group; p-value=0.0015), and MetS (moderate magnitude in favor of the sports group; p-value=0.001).

CONCLUSIONS

The practice of sports in adolescents had a protective effect on the metabolic components of MetS.

Biomarker Signatures of Two Phenotypical Prefrailty Types in the Irish Longitudinal Study on Ageing

We investigated the biomarker signatures of two previously reported phenotypical prefrailty (PF) types in the first wave of The Irish Longitudinal Study on Ageing (TILDA): PF1 (unexplained weight loss and/or exhaustion) and PF2 (one or two among slowness, weakness, and low physical activity). Binary logistic regression models evaluated the independent associations between available plasma biomarkers and each PF type (compared to robust and compared to each other), while adjusting for age, sex, and education. A total of 5307 participants were included (median age 61 years, 53% women) of which 1473 (28%) were prefrail (469 PF1; 1004 PF2), 171 were frail, and 3663 were robust. The PF2 median age was eight years older than the PF1 median age. Higher levels of lutein and zeaxanthin were independently associated with the lower likelihood of PF1 (OR: 0.77, p < 0.001 and OR: 0.81, p < 0.001, respectively). Higher cystatin C was associated with PF1 (OR: 1.23, p = 0.001). CRP (OR: 1.19, p < 0.001), cystatin C (OR: 1.36, p < 0.001), and HbA1c (OR: 1.18, p < 0.001) were independently associated with PF2, while a higher total (OR: 0.89, p = 0.004) and HDL (OR: 0.87, p < 0.001) cholesterol seemed to be PF2-protective. While PF1 seemed to be inversely associated with serum carotenoid concentrations and hence has an oxidative signature, PF2 seemed to have pro-inflammatory, hyperglycemic, and hypolipidemic signatures. Both PF types were associated with higher cystatin C (lower kidney function), but no biomarkers significantly distinguished PF1 vs. PF2. Further research should elucidate whether therapies for different PF types may require targeting of different biological pathways.

Integrative Analyses Reveal Tstd1 as a Potential Modulator of HDL Cholesterol and Mitochondrial Function in Mice

High-density lipoprotein (HDL) cholesterol levels are closely associated with human health and diseases. To identify genes modulating plasma HDL levels, we integrated HDL measurements and multi-omics data collected from diverse mouse cohorts and combined a list of systems genetics methods, including quantitative trait loci (QTL) mapping analysis, mediation analysis, transcriptome-wide association analysis (TWAS), and correlation analysis. We confirmed a significant and conserved QTL for plasma HDL on chromosome 1 and identified that Tstd1 liver transcript correlates with plasma HDL in several independent mouse cohorts, suggesting Tstd1 may be a potential modulator of plasma HDL levels. Correlation analysis using over 70 transcriptomics datasets in humans and mice revealed consistent correlations between Tstd1 and genes known to be involved in cholesterol and HDL regulation. Consistent with strong enrichment in gene sets related to cholesterol and lipoproteins in the liver, mouse strains with high Tstd1 exhibited higher plasma levels of HDL, total cholesterol and other lipid markers. GeneBridge using large-scale expression datasets identified conserved and positive associations between TSTD1/Tstd1 and mitochondrial pathways, as well as cholesterol and lipid pathways in human, mouse and rat. In summary, we identified Tstd1 as a new modulator of plasma HDL and mitochondrial function through integrative systems analyses, and proposed a new mechanism of HDL modulation and a potential therapeutic target for relevant diseases. This study highlights the value of such integrative approaches in revealing molecular mechanisms of complex traits or diseases.

Role of Mind-Body Intervention on Lipid Profile: A Cross-sectional Study

Background

Yoga is a combination of physical-breathing and meditative techniques that assist in the unification of the mind-body, which improves the quality of life. It was shown that long-term Yoga practitioners had superior control over respiratory rate, reduced stress and anxiety, and a better-controlled lipid profile.

Purpose

We aimed to investigate the lipid profile of long-term yoga practitioners who were practicing yoga for more than 1 year in comparison with the nonyoga group.

Methods

A nationwide survey was conducted in which the long-term yoga practitioners (n = 76) and nonyoga practitioners (n = 80) were recruited for assessment for the lipid parameters.

Results

The mean (standard deviation) values of both groups were within normal range with serum cholesterol at 189.715 ± 20.4 and 180.88 ± 29.7 and triglycerides at 216.72 ± 92.5 and 207.665 ± 88.3, low-density lipoprotein at 126.65 ± 18.5 and 120.775 ± 26.5, and high-density lipoprotein at 47.17 ± 6.6 and 44.99 ± 7.0, respectively, in yoga and no-yoga groups.

Conclusion

The lipid profile values were similar in yoga and nonyoga practitioners in the 2017 survey.

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

Identification and characterization of anti-diabetic principle in Senna alata (Linn.) flower using alloxan-induced diabetic male Wistar rats

ETHNO-PHARMACOLOGICAL RELEVANCE

The age-long folkloric use of Senna alata flower (SAF) was recently substantiated with scientific evidence. However, the study did not account for the anti-diabetic principle(s) in SAF.

AIM OF THE STUDY

The study aimed to identify and characterize the bioactive principle(s) responsible for the anti-diabetic activity in SAF.

MATERIALS AND METHODS

Ninety-one male Wistar rats were used for the two phases of this study. In phase 1, forty-two of these were allotted into six groups (A-F) of seven rats each. Animals in group A received distilled water while those in groups B-F were made diabetic by treatment with 150 mg/kg body weight (b.w.) of alloxan. Group B received 0.5 mL of distilled water; C, D and E were treated each with 75 mg/kg b.w. of ethyl acetate, n-butanol and aqueous residual fractions of SAF, while F received 2.5 mg/kg b.w. of glibenclamide. In the second phase, forty-nine rats were assigned into seven groups (A-G) of seven rats each. Group A received distilled water. Animals in Groups B-G were also made diabetic by alloxan treatment. B received 0.5 mL of distilled water; C, D, E and F were treated with 5.77, 25.96, 15.40, 27.87 mg/kg b.w (equivalent dose of 75 mg/kg b.w.) of sub-fractions obtained from the ethyl acetate fraction of SAF respectively whereas G received 2.5 mg/kg b.w. of glibenclamide. Fasting blood glucose (FBG), serum lipids, albumin, globulin, liver glycogen, urine ketone, hexokinase and glucose-6-phosphate dehydrogenase activities, α-glucosidase and α-amylase inhibitory activities and cardiac function indices were evaluated using standard methods. Compounds D, E and F isolated from ethyl acetate sub-fraction B were evaluated for in vitro anti-diabetic activity. The structure of the anti-diabetic compound was identified using FTIR, ¹H-NMR, ¹³C-NMR, HCOSY, HSQC and HMBC. Data were subjected to Analysis of Variance and Duncan Multiple Range Test at p < 0.05.

RESULTS

Alloxan treatment increased the levels of FBG, total cholesterol, LDL-cholesterol, VLDL-cholesterol, urine ketone and cardiac function indices and reduced the levels of globulin, albumin, HDL-cholesterol, globulin, liver glycogen, hexokinase and glucose-6-phosphate dehydrogenase activities. Ethyl acetate fraction and sub-fraction B reversed the level and/or activities of these biochemical indices to levels and/or activities that compared favourably with the distilled water treated non-diabetic animals. Of the three compounds (D, E and F) that were obtained from the sub-fraction B, compound E which was Emodin (1, 3, 8-trihydroxy-6-methylanthraquinone) produced the highest α-glucosidase and α-amylase inhibitory activities.

CONCLUSION

Emodin is one of the bioactive constituents present in Senna alata flower.

Diabetes Impairs Cellular Cholesterol Efflux From ABCA1 to Small HDL Particles

RATIONALE

HDL (high-density lipoprotein) may be cardioprotective because it accepts cholesterol from macrophages via the cholesterol transport proteins ABCA1 (ATP-binding cassette transporter A1) and ABCG1 (ATP-binding cassette transporter G1). The ABCA1-specific cellular cholesterol efflux capacity (ABCA1 CEC) of HDL strongly and negatively associates with cardiovascular disease risk, but how diabetes mellitus impacts that step is unclear.

OBJECTIVE

To test the hypothesis that HDL's cholesterol efflux capacity is impaired in subjects with type 2 diabetes mellitus.

METHODS AND RESULTS

We performed a case-control study with 19 subjects with type 2 diabetes mellitus and 20 control subjects. Three sizes of HDL particles, small HDL, medium HDL, and large HDL, were isolated by high-resolution size exclusion chromatography from study subjects. Then we assessed the ABCA1 CEC of equimolar concentrations of particles. Small HDL accounted for almost all of ABCA1 CEC activity of HDL. ABCA1 CEC-but not ABCG1 CEC-of small HDL was lower in the subjects with type 2 diabetes mellitus than the control subjects. Isotope dilution tandem mass spectrometry demonstrated that the concentration of SERPINA1 (serpin family A member 1) in small HDL was also lower in subjects with diabetes mellitus. Enriching small HDL with SERPINA1 enhanced ABCA1 CEC. Structural analysis of SERPINA1 identified 3 amphipathic α-helices clustered in the N-terminal domain of the protein; biochemical analyses demonstrated that SERPINA1 binds phospholipid vesicles.

CONCLUSIONS

The ABCA1 CEC of small HDL is selectively impaired in type 2 diabetes mellitus, likely because of lower levels of SERPINA1. SERPINA1 contains a cluster of amphipathic α-helices that enable apolipoproteins to bind phospholipid and promote ABCA1 activity. Thus, impaired ABCA1 activity of small HDL particles deficient in SERPINA1 could increase cardiovascular disease risk in subjects with diabetes mellitus.

Does Lifestyle Exercise After a Cardiac Event Improve Metabolic Syndrome Profile in Older Adults?

BACKGROUND

Exercise is a common recommendation to reduce the risk factors of metabolic syndrome, yet there are limited data on the influence of lifestyle exercise after cardiac events on metabolic syndrome factors.

OBJECTIVE

The purpose of this study was to determine whether lifestyle exercise improves metabolic syndrome profile in older adults after a cardiac event.

METHODS

Participants were from a post-cardiac-event lifestyle exercise study. Five metabolic syndrome factors were assessed: waist circumference, triglycerides, high-density lipids, glucose, and systolic and diastolic blood pressure. Objective measures of exercise were obtained from heart rate monitors over a year. Logistic regression was used to determine whether participants who engaged in the minimum recommendation of 130 hours of exercise or greater during the 12-month period improved their metabolic syndrome profile by improving at least 1 metabolic syndrome factor.

RESULTS

In the sample of 116 participants (74% men; average age, 67.5 years), 43% exercised at the recommended amount (≥130 h/y) and 28% (n = 33) improved their metabolic syndrome profile. After controlling for confounding factors of age, gender, race, diabetes, functional ability, and employment, subjects who exercised at least 130 hours a year were 3.6 times more likely to improve at least 1 metabolic syndrome factor (95% confidence interval, 1.24-10.49). Of the 28% who improved their metabolic syndrome profile, 72% increased their high-density lipoprotein and 60.6% reduced their waist circumference and glucose.

CONCLUSIONS

After a cardiac event, older patients who engage in lifestyle exercise at the recommended amount have improvement in their metabolic syndrome profile.

Effects of Regular Aerobic Exercise and Resistance Training on High-Density Lipoprotein Cholesterol Levels in Taiwanese Adults

Increased levels of high-density lipoprotein cholesterol (HDL-C) can improve endothelial function. This may help reduce cardiovascular risks and mortality. Evidence has been provided on the association between cardiometabolic traits, such as HDL-C and exercise modalities. However, there is the absence of studies investigating this association in Taiwan. We assessed the relationship between exercise type and HDL-C among Taiwanese adults. Data were collected from Taiwan Biobank (TWB), a national biomedical research database that contains the genetic information of ethnic Taiwanese residents gathered from 2008 to 2016. We enrolled 24,856 participants aged 30 to 70 years who completed a questionnaire about their recent health behaviors including smoking, drinking, and exercise. Regular exercise was categorized as non-aerobic exercise (separated as weight training, ball game, and mixed exercise) and strict aerobic exercise. Linear regression models were used to assess the effects of exercise in a questionnaire-based manner. After multivariate adjustments, HDL-C was positively associated with aerobic (β = 1.33748, p < 0.0001) and non-aerobic (β = 2.56210; p < 0.0001) exercise. Positive associations were also found for resistance training (β = 4.01828, p = 0.0020), ballgame (β = 2.43815, p = 0.0001), and mixed exercise (β = 2.47021, p < 0.0001). This study demonstrated that both aerobic and non-aerobic exercise have positive effects on HDL-C among Taiwanese adults. Among the non-aerobic exercise groups, resistance training had the greatest effect.

Duration-response association between exercise and HDL in both male and female Taiwanese adults aged 40 years and above

BACKGROUND

Exercise is an important cardiovascular risk reducing therapy.

OBJECTIVE

The aim of this study was to assess the relationship between weekly exercise duration and high-density lipoprotein cholesterol (HDL-c) in Taiwanese men and women.

METHODS

Data were retrieved from the dataset of the national adult preventive medical services which is recorded under the Health Promotion Administration (HPA). The lipid profiles of 194528 eligible participants aged 40 years and above who completed a questionnaire on recent health behavior including smoking, drinking, exercise and other factors in 2014 were determined. Weekly exercise durations of 0.0, <2.5 and ≥2.5 hours were classified as no, below recommended and recommended, respectively. The relationship between exercise and HDL-c was determined using linear regression.

RESULTS

After multivariate adjustments, a duration-response association existed between exercise and HDL-c (P-trend <0.0001) in both sexes. Weekly exercise durations of <2.5 and ≥2.5 hours were both positively associated with HDL-c (P <0.0001) in both sexes. However, the associations were stronger in males than females in both exercise groups. Smoking (P <0.05) and BMI (P <0.0001) were negatively associated while drinking was positively associated with HDL-c in both sexes.

CONCLUSION

This study demonstrated a duration-response association between exercise and HDL-c. Exercise at durations below the minimum weekly recommendation of 2.5 hours was positively associated with HDL-c.

Hepatocyte estrogen receptor alpha mediates estrogen action to promote reverse cholesterol transport during Western-type diet feeding

OBJECTIVE

Hepatocyte deletion of estrogen receptor alpha (LKO-ERα) worsens fatty liver, dyslipidemia, and insulin resistance in high-fat diet fed female mice. However, whether or not hepatocyte ERα regulates reverse cholesterol transport (RCT) in mice has not yet been reported.

METHODS AND RESULTS

Using LKO-ERα mice and wild-type (WT) littermates fed a Western-type diet, we found that deletion of hepatocyte ERα impaired in vivo RCT measured by the removal of ³H-cholesterol from macrophages to the liver, and subsequently to feces, in female mice but not in male mice. Deletion of hepatocyte ERα decreased the capacity of isolated HDL to efflux cholesterol from macrophages and reduced the ability of isolated hepatocytes to accept cholesterol from HDL ex vivo in both sexes. However, only in female mice, LKO-ERα increased serum cholesterol levels and increased HDL particle sizes. Deletion of hepatocyte ERα increased adiposity and worsened insulin resistance to a greater degree in female than male mice. All of the changes lead to a 5.6-fold increase in the size of early atherosclerotic lesions in female LKO-ERα mice compared to WT controls.

CONCLUSIONS

Estrogen signaling through hepatocyte ERα plays an important role in RCT and is protective against lipid retention in the artery wall during early stages of atherosclerosis in female mice fed a Western-type diet.

Lipoprotein lipase and lipid profiles in plasma and placenta from normal pregnancies compared with patients with intrahepatic cholestasis of pregnancy

OBJECTIVE

To analyse lipoprotein lipase (LPL) expression and lipid levels in placenta and plasma of patients with intrahepatic cholestasis of pregnancy (ICP) and normal pregnancies.

METHODS

This prospective study included 30 patients with ICP and 30 gestational-age-matched pregnancies without any complications. Enzyme-linked immunosorbent assays were used to investigate plasma LPL levels from 28 weeks of gestation, at 4-weekly intervals, to 38 weeks of gestation, and data were assessed longitudinally. Immunohistochemistry, Western blotting and real-time polymerase chain reaction were used to detect placental LPL expression and activity. Placental triglyceride and total cholesterol levels were also analysed. The clinical data related to ICP and lipid profiles were collected retrospectively.

RESULTS

Plasma LPL concentration increased with gestational age in both groups, but the increase was limited in the ICP group. Immunohistochemistry revealed LPL staining mainly in syncytiotrophoblasts, and 3,3'-diamino-benzidine tetrahydrochloride wt% was lower in ICP placenta compared with normal placenta (p<0.01). LPL protein and mRNA expression in ICP placenta were significantly lower than in normal placenta (p<0.01). LPL activity was not significantly different in both groups. Correlation analysis indicated that the plasma LPL level was negatively associated with the corresponding concentration of total bile acid (r=-0.57) in the ICP group.

CONCLUSION

Reduced LPL expression in placenta, limited increase in LPL level in maternal plasma, and abnormal lipid profiles were found in patients with ICP. LPL was possibly related to ICP by participating abnormal lipid metabolism.