Reassessing lipid metabolism and its potentialities in the prediction of cardiovascular risk

Role of Phytoestrogen-Rich Bioactive Substances (Linum usitatissimum L., Glycine max L., Trifolium pratense L.) in Cardiovascular Disease Prevention in Postmenopausal Women: A Systematic Review and Meta-Analysis

The aim of this report was to determine the impact of flaxseed, soy and red clover, and their bioactive substances on the lipid profile in postmenopausal women in cardiovascular diseases prevention. We used the following databases: MEDLINE (PubMed), EMBASE and the Cochrane Library. Meta-analysis indicates that the intake of flaxseed by postmenopausal women is associated with a statistically significant reduction in total cholesterol (TC) levels (weighted-mean difference (WMD) = -0.26; 95% confidence interval (95% CI): -0.38 to -0.13; p = 0.0001), low-density lipoprotein cholesterol (LDL-C) levels (WMD = -0.19; 95% CI: -0.30 to -0.08; p = 0.0006), and high-density lipoprotein cholesterol (HDL-C) levels (WMD = -0.06; 95% CI: -0.11 to -0.01; p = 0.0150). The effect of soy protein on the lipid profile showed a significant decrease in TC levels: WMD = -0.15; 95% CI: -0.25-0.05; p = 0.0048, LDL-C levels: WMD = -0.15; 95% CI: -0.25-0.05; p = 0.0067, as well as a significant increase in HDL-C levels: WMD = 0.05; 95% CI: 0.02-0.08; p = 0.0034. Changes in the lipid profile showed a significant reduction in TC levels after the use of red clover (WMD = -0.11; 95% CI: -0.18--0.04; p = 0.0017) and a significant increase in HDL-C levels (WMD = 0.04; 95% CI: 0.01 to 0.07; p = 0.0165). This meta-analysis provides evidence that consuming flaxseed, soy and red clover can have a beneficial effect on lipids in postmenopausal women and suggest a favorable effect in preventing cardiovascular diseases.

Phytochemical‑rich herbal formula ATG‑125 protects against sucrose‑induced gastrocnemius muscle atrophy by rescuing Akt signaling and improving mitochondrial dysfunction in young adult mice

The antioxidant capability of herbal remedies has attracted widespread attention, but their molecular mechanisms in a muscle atrophy model have not been explored. The aim of the present study was to compare the bioactivity of sucrose challenged mice following treatment with ATG‑125. Here, through a combination of transcriptomic and biomedical analysis, herbal formula ATG‑125, a phytochemical‑rich formula, was identified as a protective factor against muscle atrophy in sucrose challenged mice. Gene ontology (GO) identified differentially expressed genes that were primarily enriched in the 'negative regulation of proteolysis', 'cellular amino acid metabolic process', 'lipoprotein particle' and 'cell cycle', all of which were associated with the ATG‑125‑mediated prevention of muscle atrophy, particularly with regard to mitochondrial biogenesis. In skeletal muscle, a set of mitochondrial‑related genes, including angiopoietin‑like 4, nicotinamide riboside kinase 2 (Nmrk2), pyruvate dehydrogenase lipoamide kinase isozyme 4, Asc‑type amino acid transporter 1 and mitochondrial uncoupling protein 3 (Ucp3) were markedly upregulated following ATG‑125 intervention. An increase in Nmrk2 and Ucp3 expression were noted after ATG‑125 treatment, in parallel with upregulation of the 'nicotinate and nicotinamide metabolism' pathway, as determined using the Kyoto Encyclopedia of Genes and Genomes (KEGG). Furthermore, KEGG pathway analysis revealed the downregulation of 'complement and coagulation cascades', 'cholesterol metabolism', 'biosynthesis of amino acids' and 'PPAR signaling pathway', which were associated with the downregulation of serine (or cysteine) peptidase inhibitor clade A member (Serpina)3, Serpina1b, Serpina1d, Serpina1e, apolipoprotein (Apo)a1 and Apoa2, all of which were cardiovascular and diabetes‑associated risk factors and were regulated by ATG‑125. In addition, ATG‑125 treatment resulted in downregulated mRNA expression levels of ATPase sarcoplasmic/endoplasmic reticulum Ca2+ transporting 2, troponin‑I1, troponin‑C1 and troponin‑T1 in young adult gastrocnemius muscle compared with the sucrose group. Nuclear factor‑κB‑hypoxia inducible factor‑1α‑TGFβ receptor type‑II‑vascular endothelial growth factor staining indicated that ATG‑125 decreased sucrose‑induced chronic inflammation. ATG‑125 was sufficient to prevent muscle atrophy, and this protective effect may be mediated through upregulation of AKT phosphorylation, upregulating the insulin growth factor‑1R‑insulin receptor substrate‑PI3K‑AKT pathway, which in turn resulted in a forkhead box O‑dependent decrease in protein degradation pathways, including regulation of atrogin1 and E3 ubiquitin‑protein ligase TRIM63. Peroxisome‑proliferator activated receptor γ coactivator 1α (PGC1α) was decreased in young adult mice challenged with sucrose. ATG‑125 treatment significantly increased PGC1α and significantly increased UCP‑1,2,3 expression levels, which suggested ATG‑125 poised the mitochondria for uncoupling of respiration. This effect is consistent with the increased SIRT1 levels and may explain an increase in mitochondria biogenesis. Taken together, the present study showed that ATG‑125, as an integrator of protein synthesis and degradative pathways, prevented muscle wasting.

Association of circulating selenium concentration with dyslipidemia: Results from the NHANES

BACKGROUND

Observational studies have suggested that selenium levels might associate with the risk of cardio-metabolic diseases, but how circulating selenium is related to dyslipidemia remains inconclusive.

OBJECTIVES

To investigate the association of circulating selenium levels with lipid profiles and dyslipidemia among US adults.

METHODS

Using the data collected from the National Health and Nutrition Examination Survey (NHANES 1999-2006), we performed multivariate logistic regression to examine the association of circulating selenium levels (in quartiles) with total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-HDL-C, and atherogenic index (AI).

RESULTS

We included 2903 adults (49.3 % male) (average age: 61.9) for analysis. Circulating selenium had non-linear association with TC, LDL-C, HDL-C, and AI (all p < 0.05). When comparing with the lowest quartile, subjects with the highest quartile of circulating selenium (>147.00 μg/L) had the higher odds of elevated TG (OR: 1.75, 95% CI = 1.14, 2.68), TC (OR: 2.47, 95% CI = 1.62, 3.76), LDL-C (OR: 2.52, 95% CI = 1.60, 3.96), non-HDL-C (OR: 2.17, 95% CI = 1.41, 3.33), AI (OR: 1.20, 95% CI = 0.73, 1.97) and low-HDL-C (OR: 2.10, 95% CI = 1.19, 3.72). Similar patterns were observed in subgroup analysis.

CONCLUSIONS

Higher circulating selenium levels had non-linear association with lipid profiles and the increased odds of dyslipidemia.

Menopause-Associated Lipid Metabolic Disorders and Foods Beneficial for Postmenopausal Women

Menopause is clinically diagnosed as a condition when a woman has not menstruated for one year. During the menopausal transition period, there is an emergence of various lipid metabolic disorders due to hormonal changes, such as decreased levels of estrogens and increased levels of circulating androgens; these may lead to the development of metabolic syndromes including cardiovascular diseases and type 2 diabetes. Dysregulation of lipid metabolism affects the body fat mass, fat-free mass, fatty acid metabolism, and various aspects of energy metabolism, such as basal metabolic ratio, adiposity, and obesity. Moreover, menopause is also associated with alterations in the levels of various lipids circulating in the blood, such as lipoproteins, apolipoproteins, low-density lipoproteins (LDLs), high-density lipoproteins (HDL) and triacylglycerol (TG). Alterations in lipid metabolism and excessive adipose tissue play a key role in the synthesis of excess fatty acids, adipocytokines, proinflammatory cytokines, and reactive oxygen species, which cause lipid peroxidation and result in the development of insulin resistance, abdominal adiposity, and dyslipidemia. This review discusses dietary recommendations and beneficial compounds, such as vitamin D, omega-3 fatty acids, antioxidants, phytochemicals—and their food sources—to aid the management of abnormal lipid metabolism in postmenopausal women.

Performance Characteristics and Clinical Value of the Lipoprotein-Associated Phospholipase A2 by an Enzymatic Kinetic Method

OBJECTIVE

To analyze the performance characteristics, stability, and clinical value of lipoprotein-associated phospholipase A2 (Lp-PLA2) using an enzymatic kinetic method.

METHODS

The performance characteristics included reference intervals, precision, and accuracy. We assessed Lp-PLA2 stability by comparing Lp-PLA2 changes under different conditions. Lp-PLA2 was determined in the following groups: control individuals, patients with coronary heart disease (CHD), patients of different lipid subgroups within CHD, and patients with high total cholesterol (TC). Also, correlations between Lp-PLA2 and traditional cardiovascular risk factors were assessed.

RESULTS

The mean (SD) reference interval of serum Lp-PLA2 activity was 451 (113) U per L with sex differences. Inter- and intra-assay precision revealed coefficients of variance (CVs) of 1.81% to 2.63% and 1.43% to 1.77%. The average bias was 0.33%. Lp-PLA2 activity was stable. In the CHD group, high-lipid subgroups, and high-TC group, Lp-PLA2 was elevated, and correlation was observed between Lp-PLA2 and traditional risk factors.

CONCLUSION

Lp-PLA2 activity has important clinical value in CHD.

Recommended reference values for serum lipids during early and middle pregnancy: a retrospective study from China

Background

Disturbances in maternal lipid metabolism have been shown to increase the risk of adverse pregnancy outcomes. However, there is no consensus as to what constitutes normal maternal lipid values during pregnancy. Thus, the aim of this study was to establish serum lipid reference ranges during early and middle pregnancy.

Methods

We conducted a retrospective survey in Beijing from 2013 to 2014. A total of 17,610 singleton pregnancies with lipid data from early and middle pregnancy were included. First, after excluding women with adverse pregnancy outcomes, we performed a descriptive analysis of total cholesterol (TC), triglycerides (TG), high-density lipid cholesterol (HDL-C) and low-density lipid cholesterol (LDL-C) levels using means and standard deviations to determine appropriate percentiles. Second, in the total population, we examined the lipid levels in different trimesters with the risk of adverse pregnancy outcomes using categorical analyses and logistic regression models. Third, we determined the lipid reference range in early and middle pregnancy based on the first two results. Finally, based on the reference ranges we determined, we assessed whether the number of abnormal lipid values affected the risk of adverse pregnancy outcomes.

Results

(1) Serum levels of TC, TG, LDL-C and HDL-C all increased significantly from early to middle pregnancy, with the greatest increase in TG. (2) A trend towards an increasing incidence of adverse pregnancy outcomes was observed with increasing levels of TC, TG, and LDL-C and decreasing levels of HDL-C in both early and middle pregnancy. (3) We recommend that serum TC, TG and LDL-C reference values in early and middle pregnancy should be less than the 95th percentiles, whereas that of HDL-C should be greater than the 5th percentile, i.e., in early pregnancy, TC < 5.64 mmol/L, TG < 1.95 mmol/L, HDL-C > 1.23 mmol/L, and LDL-C < 3.27 mmol/L, and in middle pregnancy, TC < 7.50 mmol/L, TG < 3.56 mmol/L, HDL-C > 1.41 mmol/L, and LDL-C < 4.83 mmol/L. (4) Higher numbers out-of-range lipids during early and middle pregnancy were correlated with a higher risk of adverse pregnancy outcomes.

Conclusions

The reference ranges recommended in this paper can identify pregnant women with unfavourable lipid values.

Impact of smoking on the observed levels of apolipoprotein B: Data from NHANES 2007-2012

Impact of smoking on the levels of apolipoprotein B (APOB) was evaluated by analyzing data from National Health and Nutrition Examination Survey for the years 2007-2012 for US adolescents aged 12-19 years and adults aged >=20 years. When adjustments were made for the effects of age, gender, race/ethnicity, body mass index, and poverty income ratio, smoking did not influence the observed levels of APOB for either adolescents or adults. Moreover, even the variables that represented intensity of smoking indicated, for example, by the number of days participants smoked during the last five days and/or the number of cigarettes smoked on the days they were smoked did not affect the levels of APOB. Also, type of smoking, cigarettes only, cigars only, or smokeless products only did not affect the levels of APOB. Every two years, adjusted levels of APOB decreased by 2.5% for adolescents and by 1.8% for adults.

The associations between early pregnancy lipid profiles and pregnancy outcomes

OBJECTIVE

To evaluate the association between early pregnancy lipid profiles and pregnancy outcomes.

STUDY DESIGN

Retrospective 6 months analysis of 5218 singleton pregnant women. Each participant's demographic and medical data were collected by questionnaires and medical records. Total cholesterol (TC), triglycerides (TG), high-density lipid cholesterol (HDL-C) and low-density lipid cholesterol (LDL-C) levels were divided into quartiles, and the women were categorized as having low (<25th percentile), referent (25 to <75th percentile) or high (>75th percentile) TC, TG, HDL-C and LDL-C values. Differences between groups were tested using t-test and Pearson's χ²-test. Binary logistic regression and multivariate analysis was conducted to evaluate the associations between lipid values and the risk of pregnancy outcomes.

RESULTS

(1) Women who subsequently developed adverse pregnancy outcomes had higher levels of TC, TG, LDL-C and lower levels of HDL-C during early pregnancy (<14 gestational weeks). (2) A trend toward an increasing incidence of adverse pregnancy outcomes was noted with increasing levels of TC, TG and LDL-C, and decreasing level of HDL-C. (3) The more numbers of TC, TG and LDL-C above 75th percentile and HDL-C inferior to 25th percentile women had, the higher their risk of developing adverse pregnancy outcomes. (4) Low TG level was a protective factor for gestational diabetes mellitus (GDM) (<1.44 mmol l^-1, odds ratio (OR)=0.706, 95% confidence interval (CI), 0.586 to 0.852) and large for gestational age infants (LGA) (<1.44 mmol l^-1, OR=0.769, 95% CI, 0.631 to 0.936), and low LDL-C (<1.89 mmol l^-1) level was protective factor for preterm birth. High TG (>1.40 mmol l^-1, OR=1.327, 95% CI, 1.130 to 1.558), TC (>4.29 mmol l^-1, OR=1.250, 95% CI, 1.062 to 1.471), and LDL-C (>2.62 mmol l^-1, OR=1.25, 95% CI, 1.069 to 1.480) levels and a low HDL-C (<1.89 mmol l^-1, OR=1.190, 95% CI, 1.007 to 1.405) level were associated with increased risk of GDM. A high TG (>1.40 mmol l^-1, OR=1.550, 95% CI, 1.025 to 2.343) level was related to high risk of pre-eclampsia (PE), while a high LDL-C (>2.62 mmol l^-1, OR=1.400, 95% CI, 1.100 to 1.781) level was risk factor for macrosomia. (5) After adjusting for confounders, early pregnancy TC was an independent risk factor for GDM (ajusted odds ratio [aOR]=1.184, 95% CI, 1.085 to 1.291), TG level was independently associated with the prevalence of GDM (aOR=1.253, 95% CI, 1.141 to 1.375) and PE (aOR=1.245, 95% CI, 1.023 to 1.516), and LDL-C level was significantly associated with risk of GDM (aOR=1.162, 95% CI, 1.052 to 1.283) and preterm birth (aOR=1.264, 95% CI, 1.065, 1.501).

CONCLUSIONS

Early pregnancy high levels of TC, TG, LDL-C and low level of HDL-C may be predictive biomarkers for adverse pregnancy outcomes, while early pregnancy low TC, TG, LDL-C levels and high HDL-C levels could have some protective roles.

Isoorientin Prevents Hyperlipidemia and Liver Injury by Regulating Lipid Metabolism, Antioxidant Capability, and Inflammatory Cytokine Release in High-Fructose-Fed Mice

Isoorientin (ISO), a natural flavonoid, has been found to have multiple biological properties. In the present study, obese mice with high-fructose (HF)-induced liver injury were used to investigate the hepatoprotective effects of ISO. The results showed that ISO significantly reduced the serum lipid parameters in mice fed 20% HF water. Meanwhile, ISO appeared to alleviate HF-induced lipid metabolic disorders by increasing the serum levels of apo-A1 and decreasing the serum apoB levels, apoB/apo-A1 ratio, and FAS activity in the liver. ISO also remarkably ameliorated HF-induced hepatic oxidative injury and inflammation by decreasing ALT, AST, and ALP levels; enhancing antioxidant enzyme activities; and inhibiting inflammatory cytokine (TNF-α, IL-1, IL-6) release. Histopathology of liver stained by H&E and Oil Red O showed the liver steatosis and oxidative injury after HF treatment and the protective effect of ISO. Furthermore, aortic pathology observation found that ISO had a protective effect on the vascular endothelium. This is the first report that ISO efficiently inhibited HF-induced hyperlipidemia and liver injury by ameliorating lipid metabolism, enhancing the antioxidant defensedefense system, and regulating the secretion of inflammatory cytokines.

An LC-MS based untargeted metabolomics study identified novel biomarkers for coronary heart disease

This work leads to candidate diagnosis biomarker discovery in coronary heart disease which can be developed as a non-invasive and feasible method for CHD diagnosis.