Associations between plasma lipid parameters and APOC3 and APOA4 genotypes in a healthy population are independent of dietary cholesterol intake

Silencing ApoC3 alleviates LPS-induced acute lung injury by inhibiting TLR signaling pathway

This study aims to confirm whether apolipoprotein C3 (ApoC3) can regulate the inflammatory response and tissue damage in acute lung injury (ALI) and explore its regulatory pathway. ALI mouse model was established by intraperitoneal injection of lipopolysaccharide (LPS). ApoC3 levels were detected by real-time quantitative polymerase chain reaction, immunohistochemistry, and western blot assays. The levels of various inflammatory factors were detected by enzyme-linked immunosorbent assay and western blot analysis. Finally, the expression of toll-like receptor (TLR)/nuclear factor kappa B (NF-κB) signaling pathway-related protein [TLR2, myeloid differentiation primary response protein 88 (MyD88), IL-1 receptor-associated kinase 1 (IRAK1), NF-κB p65, and inhibitor of kappa B alpha (IκBα)], SLP adaptor and CSK interacting membrane protein (SCIMP), spleen tyrosine kinase (Syk), and phosphorylated (p)-Syk was detected by western blot analysis. ApoC3 was overexpressed in ALI mouse lung tissue and cell inflammation model. Silencing ApoC3 reduced inflammatory factors and alleviated lung tissue damage in ALI mice. Silencing ApoC3 reduced inflammatory factors and downregulated the expression of TLR2, MyD88, IRAK1, NF-κB p65, and increased IκBα expression in LPS-treated RAW264.7 cells. Moreover, co-transfection of si-TLR2 and shApoC3 further enhanced the inhibitory effects on the levels of inflammatory factors induced by silencing ApoC3. ApoC3 overexpression increased the levels of inflammatory factors and protein expression of SCIMP and p-Syk, while silencing TLR2 reversed the promotive effects of ApoC3 overexpression on above factors. In LPS-induced ALI mouse model and inflammatory cell model, downregulation of ApoC3 reduced inflammatory factors and relieved tissue damage. This process might be achieved through the TLR pathway.

Depression Augments Plasma APOA4 without Changes of Plasma Lipids and Glucose in Female Adolescents Carrying G Allele of APOA4 rs5104

The association of apolipoprotein AIV (APOA4) with depression or plasma levels of lipids and glucose has been inconsistently reported. However, interplays between APOA4 and depression on the levels have not been explored yet. The present study aimed to investigate plasma levels of APOA4, lipids, and glucose in adolescents with different genotypes of APOA4 rs5104 and with or without depression. Depressive symptoms were assessed in 631 adolescents by Beck Depression Inventory (BDI). A total score of 14 was defined as the cutoff point for depression. Plasma levels of triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), glucose, and insulin were measured by routine methods, and APOA4 by enzyme-linked immunosorbent assays. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism analyses and verified by DNA sequencing. Female adolescents had higher prevalence of depression than male subjects only in G allele carriers (p = 0.015), but not in AA homozygotes. Risk factors of depression and predictors of depression severity were different between G allele carriers and AA homozygotes. Lower levels of glucose (p = 0.003) were observed in male G allele carriers than those in male AA homozygotes and increased TG levels (p = 0.008) in female G allele carriers when compared with those in female AA homozygotes. When both APOA4 rs5104 and depression were taken into account, subjects with depression had higher levels of plasma APOA4 than adolescents without depression only in female G allele carriers (p = 0.043), but no significant changes of plasma lipids and glucose. Depression augments plasma APOA4 levels without changes of plasma lipids and glucose in female adolescents carrying G allele of APOA4 rs5104. These results may provide a novel explanation for the inconsistent relationship between depression, APOA4, and plasma levels of lipids and glucose in the literature.

The Debate Over Egg Consumption and Incident Cardiovascular Disease

There is a great debate regarding the association of cholesterol intake from egg consumption and the incidence of cardiovascular disease (CVD). Most studies show that moderate egg consumption is not associated with a significant increase in CVD, stroke, heart failure, and type 2 diabetes mellitus (T2DM), whereas others dispute this fact and state that there is an association with increased egg consumption, especially if they are consumed with saturated fats. In addition, the recent relaxation of cholesterol intake to greater than 300 mg/d by the American College of Cardiology/American Heart Association Nutritional Guidelines has fueled this debate. In order to get a current perspective on the significance of moderate egg consumption with the primary incidence of CVD, a focused Medline search of the English language literature was conducted between 2010 and March 2020 using the terms, cholesterol intake, egg consumption, coronary artery disease, CVD, and T2DM. Nineteen pertinent articles were retrieved, and these, together with collateral literature, will be discussed in this review article. The analysis of data from the articles retrieved indicated that several studies showed that moderate egg consumption (1 egg/d) is not associated with adverse cardiovascular effects in subjects free of CVD or T2DM, whereas other studies showed a positive association, especially in patients with preexisting CVD or T2DM. Therefore, at present, there is no unanimous agreement on this subject, and the controversy will continue until new confirmatory evidence becomes available.

Association between Egg Consumption and Cholesterol Concentration: A Systematic Review and Meta-analysis of Randomized Controlled Trials

The association of egg consumption and serum cholesterol concentrations in healthy people has been discussed for a long time. In this study, we aimed to explore association of egg consumption with on low-density lipoprotein cholesterol (LDL-c) and high-density lipoprotein cholesterol (HDL-c) concentrations and the LDL-c/HDL-c ratio through meta-analysis. This systematic review only included randomized controlled trials (RCTs) investigating egg consumption in healthy populations without combination therapy. We extracted mean and standard deviation for LDL-c/HDL-c ratio, LDL-c/HDL-c. The extracted data were pooled in a random-effects model and were presented as mean difference (MD) with 95% confidence interval (CI). Moreover, subgroup analyses were conducted for understanding effects of more egg consumption (MEC) on different intervention periods, egg-consumption levels, classification of responders. Overall, 17 RCTs met the eligibility criteria and pooled results showed MEC group had a higher LDL-c/HDL-c ratio than the control group (MD = 0.14, p = 0.001, I² = 25%). The MEC group also had higher LDL-c than the control group (MD = 8.14, p < 0.0001, I² = 18%). Moreover, for the subset of intervention over two months, the MEC group seemed to have a larger effect size than the subset of intervention within two months. This synthesis, the largest meta-analysis on this topic, shows the impact of egg consumption on lipid profiles among healthy subjects. Notably, longer time with MEC may lead to higher LDL-c/HDL-c ratio and LDL-c. However, RCTs with long tern follow-up are needed to guarantee the association between egg consumption and human health.

The responses of different dosages of egg consumption on blood lipid profile: An updated systematic review and meta-analysis of randomized clinical trials

Diverse notions exist regarding egg intake, which is one of the main sources of dietary cholesterol, and its effect on blood lipids. We conducted this study to update the previous meta-analysis for their flaw in calculated effect size. PubMed, Scopus, ISI, and Cochrane were searched up to April 2019, for relevant randomized controlled clinical trials. Mean changes in total cholesterol (TC), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), triglyceride (TG), very low-density lipoprotein cholesterol (VLDL-C), LDL-C/HDL-C, TC/HDL-C, apolipoprotein (apo)A1, and apoB100 were assessed. Meta-analysis of 66 RCTs with 3,185 participants revealed that egg consumption can significantly increase TC, LDL-C, HDL-C, TC/HDL-C, apoA1/and B100, but there was no significant effect on other serum lipids. Dose-response analysis showed a linear effect for TC, HDL-C, ApoA1, ApoB100, and nonlinear for LDL-C, and TC/HDL-C. In conclusion, intake of more than one egg daily in less than 12 weeks may increase some blood lipids without any changes in the ratio of LDL-C/HDL-C. PRACTICAL APPLICATIONS: There are controversies reports for egg intake, which is one of the main sources of dietary cholesterol. This study provides comprehensive information about the effect of the number of eggs consumed per day (dietary cholesterol) on blood lipids for nutritionists, physicians, researchers, and the general population. In this regard, our results indicated that there is a linear correlation between consumption of greater than one egg per day in a short time (no long time) and increasing lipid profiles which may increase the risk of cardiovascular diseases. However, consumption of one egg daily can be safe and this can be a useful recommendation for prevention of cardiovascular disease and promotion of healthy life which indeed are the potential or actual uses of this research.

Long Noncoding RNAs: Advances in Lipid Metabolism

Long noncoding RNAs (lncRNAs) are an important group of pervasive noncoding RNAs (>200nt) proposed to be crucial regulators of numerous physiological and pathological processes. Through interactions with RNA, chromatin, and protein, lncRNAs modulate mRNA stability, chromatin structure, and the function of proteins (including transcription factors). In addition, to their well-known roles in the modulation of cell growth, apoptosis, neurological disease progression and cancer metastasis, these large molecules have also been identified as likely mediators of lipid metabolism. In particular, lncRNAs orchestrate adipogenesis; fatty acid, cholesterol, and phospholipid metabolism and transport; and the formation of high-density and low-density lipoproteins (HDLs and LDLs). LncRNAs also appear to target several transcription factors that play essential roles in the regulation of lipid metabolism, such as liver X receptors (LXRs), sterol regulatory element binding proteins (SREBPs), and peroxisome proliferator-activated receptor γ (PPARγ). Better understanding the regulatory roles of lncRNAs in dyslipidemia, atherosclerosis, and adipogenesis will reveal appropriate strategies to treat these diseases. In this review, we review recent progress in lncRNA-mediated regulation of lipid metabolism, as well as its role in the regulation of adipogenesis.

Effects of Egg Consumption on Blood Lipids: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

BACKGROUND

It is widely agreed that egg consumption only modestly influences serum lipid concentrations. However, there is no meta-analysis summarizing existing randomized controlled trials.

OBJECTIVE

The purpose of this study was to conduct a meta-analysis of published randomized controlled trials to explore the quantitative effect of egg consumption on serum lipid concentrations.

DESIGN

Online databases including MEDLINE, Proquest and Google Scholar were systematically searched. Studies that were published after 2000 and compared serum lipids concentrations in egg-consumers and non egg-consumers were included. The data were obtained from 28 studies. Weighted mean differences were calculated as the ultimate effect using random effects model.

RESULTS

Overall, egg consumption increased total cholesterol (TC) by 5.60 mg/dL (95% CI: 3.11, 8.09; P<0.0001), low density lipoprotein-cholesterol (LDL-C) by 5.55 mg/dL (95% CI: 3.14, 7.69; P<0.0001) and high density lipoprotein-cholesterol (HDL-C) by 2.13 mg/dL (95% CI: 1.10, 3.16; P<0.0001) compared with the control group. Heterogeneity found between studies was explained partly by study design and participant response to dietary cholesterol. No effect of increased egg consumption on LDL-C:HDL-C and TC:HDL-C ratios, and triglyceride (TG) concentrations were found. No association was observed between number of eggs consumed per day or study duration and any of the serum lipid markers.

CONCLUSION

Consumption of egg increases total cholesterol, LDL-C and HDL-C, but not LDL-C:HDL-C, TC:HDL-C and TG compared with low egg control diets. To assess the risk of coronary events, future studies should focus on the postprandial effect of egg consumption and effects on coronary risk.

APOC3 rs2070666 Is Associated with the Hepatic Steatosis Independently of PNPLA3 rs738409 in Chinese Han Patients with Nonalcoholic Fatty Liver Diseases

BACKGROUND AND AIM

The association between nonalcoholic fatty liver disease (NAFLD) and apolipoprotein C3 gene (APOC3) promoter region single-nucleotide polymorphisms (SNPs) rs2854117 and rs2854116 is controversial. The aim of this study was to investigate the relationship between other polymorphisms of APOC3 and NAFLD in Chinese.

METHODS

Fifty-nine liver biopsy-proven NAFLD patients and 72 healthy control subjects were recruited to a cohort representing Chinese Han population. The polymorphisms in the exons and flanking regions of APOC3 and patatin-like phospholipase domain-containing protein 3 (PNPLA3) rs738409 polymorphisms were genotyped.

RESULTS

Among the five SNPs (rs4225, rs4520, rs5128, rs2070666, and rs2070667) in APOC3, only rs2070666 (c.179 + 62 T/A) was significantly different in genotype and allele frequency (both p < 0.01) between groups of NAFLD and control. After adjusting for sex, age, serum triglycerides, total cholesterol, body mass index, and the PNPLA3 rs738409 polymorphism, the APOC3 rs2070666 A allele was an independent risk factor for NAFLD with an odds ratio (OR) of 3.683 and 95 % confidence interval (CI) of 1.037-13.084. The APOC3 rs2070666 A allele was linked to the fourth quartile of the controlled attenuation parameter values (OR 2.769, 95 % CI 1.002-7.651) in 131 subjects, and also linked to the significant histological steatosis (OR 4.986, 95 % CI 1.020-24.371), but neither to liver stiffness measurement values nor to hepatic histological activity and fibrosis in NAFLD patients.

CONCLUSIONS

The APOC3 rs2070666 A allele is a risk factor for NAFLD independent of obesity, dyslipidemia, and PNPLA3 rs738409, and it might contribute to increased liver fat content in Chinese Han population.

A long non-coding RNA, APOA4-AS, regulates APOA4 expression depending on HuR in mice

Long non-coding RNAs (lncRNAs) have been shown to be critical biomarkers or therapeutic targets for human diseases. However, only a small number of lncRNAs were screened and characterized. Here, we identified 15 lncRNAs, which are associated with fatty liver disease. Among them, APOA4-AS is shown to be a concordant regulator of Apolipoprotein A-IV (APOA4) expression. APOA4-AS has a similar expression pattern with APOA4 gene. The expressions of APOA4-AS and APOA4 are both abnormally elevated in the liver of ob/ob mice and patients with fatty liver disease. Knockdown of APOA4-AS reduces APOA4 expression both in vitro and in vivo and leads to decreased levels of plasma triglyceride and total cholesterol in ob/ob mice. Mechanistically, APOA4-AS directly interacts with mRNA stabilizing protein HuR and stabilizes APOA4 mRNA. Deletion of HuR dramatically reduces both APOA4-AS and APOA4 transcripts. This study uncovers an anti-sense lncRNA (APOA4-AS), which is co-expressed with APOA4, and concordantly and specifically regulates APOA4 expression both in vitro and in vivo with the involvement of HuR.

Nutrigenetics of cholesterol metabolism: observational and dietary intervention studies in the postgenomic era

Cholesterol metabolism is a well-defined responder to dietary intakes and a classic biomarker of cardiovascular health. For this reason, circulating cholesterol levels have become key in shaping nutritional recommendations by health authorities worldwide for better management of cardiovascular disease, a leading cause of mortality and one of the most costly health problems globally. Data from observational and dietary intervention studies, however, highlight a marked between-individual variability in the response of cholesterol metabolism to similar dietary protocols, a phenomenon linked to genetic heterogeneity. This review summarizes the postgenomic evidence of polymorphisms within cholesterol-associated genes relative to fasting circulating cholesterol levels under diverse nutritional conditions. A number of cholesterol-related gene-diet interactions are confirmed, which may have clinical importance, supporting a deeper look into the rapidly emerging field of nutrigenetics for meaningful conclusions that may eventually lead to genetically targeted dietary recommendations in the era of personalized nutrition.

Associations of the APOC3 rs5128 polymorphism with plasma APOC3 and lipid levels: a meta-analysis

BACKGROUND

Studies of the association between the apolipoprotein C3 gene (APOC3) rs5128 polymorphism and plasma levels of apolipoprotein C3 (APOC3) and lipids have reported apparently conflicting findings. This meta-analysis aimed to investigate the associations of the rs5128 polymorphism with fasting APOC3 and lipid levels.

METHODS

The following information was abstracted for each study: ethnicity, age, sex, health condition, sample size, genotyping and lipid assay methods, mean and standard deviation or standard error by genotypes for APOC3 and lipid variables. There were 42 eligible studies with 23846 subjects included in this meta-analysis. A dominant model was used for this meta-analysis.

RESULTS

The results showed that the carriers of the variant allele G had higher levels of APOC3 [standardized mean difference (SMD): 0.22, 95% confidence interval (CI): 0.12-0.31, P<0.00001], triglycerides (TG) (SMD: 0.33, 95% CI: 0.23-0.44, P<0.00001), total cholesterol (TC) (SMD: 0.15, 95% CI: 0.09-0.22, P<0.00001), and low-density lipoprotein cholesterol (LDL-C) (SMD: 0.11, 95% CI: 0.04-0.17, P=0.001) than the non-carriers. No significant association between the APOC3 rs5128 polymorphism and lower levels of high-density lipoprotein cholesterol (HDL-C) was detected under the dominant model (SMD: -0.03, 95% CI: -0.06-0.01, P=0.156).

CONCLUSIONS

The results from the present meta-analysis demonstrate a significant association between the APOC3 rs5128 polymorphism and higher levels of APOC3, TG, TC and LDL-C, but further studies are needed to elucidate the underlying mechanisms.

Vertical sleeve gastrectomy restores glucose homeostasis in apolipoprotein A-IV KO mice

Bariatric surgery is the most successful strategy for treating obesity, yet the mechanisms for this success are not clearly understood. Clinical literature suggests that plasma levels of apolipoprotein A-IV (apoA-IV) rise with Roux-en-Y gastric bypass (RYGB). apoA-IV is secreted from the intestine postprandially and has demonstrated benefits for both glucose and lipid homeostasis. Because of the parallels in the metabolic improvements seen with surgery and the rise in apoA-IV levels, we hypothesized that apoA-IV was necessary for obtaining the metabolic benefits of bariatric surgery. To test this hypothesis, we performed vertical sleeve gastrectomy (VSG), a surgery with clinical efficacy very similar to that for RYGB, in whole-body apoA-IV knockout (KO) mice. We found that VSG reduced body mass and improved both glucose and lipid homeostasis similarly in wild-type mice compared with apoA-IV KO mice. In fact, VSG normalized the impairment in glucose tolerance and caused a significantly greater improvement in hepatic triglyceride storage in the apoA-IV KO mice. Last, independent of surgery, apoA-IV KO mice had a significantly reduced preference for a high-fat diet. Altogether, these data suggest that apoA-IV is not necessary for the metabolic improvements shown with VSG, but also suggest an interesting role for apoA-IV in regulating macronutrient preference and hepatic triglyceride levels. Future studies are necessary to determine whether this is the case for RYGB as well.

Monogenic causes of elevated HDL cholesterol and implications for development of new therapeutics

Identification of the CETP, LIPG (encoding endothelial lipase) and APOC3 genes, and ana lysis of rare genetic variants in them, have allowed researchers to increase understanding of HDL metabolism significantly. However, development of cardiovascular risk-reducing therapeutics targeting the proteins encoded by these genes has been less straightforward. The failure of two CETP inhibitors is complex but illustrates a possible over-reliance on HDL cholesterol as a marker of therapeutic efficacy. The case of endothelial lipase exemplifies the importance of utilizing population-wide genetic studies of rare variants in potential therapeutic targets to gain information on cardiovascular disease end points. Similar population-wide studies of cardiovascular end points make apoC-III a potentially attractive target for lipid-related drug discovery. These three cases illustrate the positives and negatives of single-gene studies relating to HDL-related cardiovascular drug discovery; such studies should focus not only on HDL cholesterol and other components of the lipid profile, but also on the effect genetic variants have on cardiovascular end points.

Re-sequencing of the APOAI promoter region and the genetic association of the -75G > A polymorphism with increased cholesterol and low density lipoprotein levels among a sample of the Kuwaiti population

Background

APOAI, a member of the APOAI/CIII/IV/V gene cluster on chromosome 11q23-24, encodes a major protein component of HDL that has been associated with serum lipid levels. The aim of this study was to determine the genetic association of polymorphisms in the APOAI promoter region with plasma lipid levels in a cohort of healthy Kuwaiti volunteers.

Methods

A 435 bp region of the APOAI promoter was analyzed by re-sequencing in 549 Kuwaiti samples. DNA was extracted from blood taken from 549 healthy Kuwaiti volunteers who had fasted for the previous 12 h. Univariate and multivariate analysis was used to determine allele association with serum lipid levels.

Results

The target sequence included a partial segment of the promoter region, 5’UTR and exon 1 located between nucleotides −141 to +294 upstream of the APOAI gene on chromosome 11. No novel single nucleotide polymorphisms (SNPs) were observed. The sequences obtained were deposited with the NCBI GenBank with accession number [GenBank: JX438706]. The allelic frequencies for the three SNPs were as follows: APOAI rs670G = 0.807; rs5069C = 0.964; rs1799837G = 0.997 and found to be in HWE. A significant association (p < 0.05) was observed for the APOAI rs670 polymorphism with increased serum LDL-C. Multivariate analysis showed that APOAI rs670 was an independent predictive factor when controlling for age, sex and BMI for both LDL-C (OR: 1.66, p = 0.014) and TC (OR: 1.77, p = 0.006) levels.

Conclusion

This study is the first to report sequence analysis of the APOAI promoter in an Arab population. The unexpected positive association found between the APOAI rs670 polymorphism and increased levels of LDL-C and TC may be due to linkage disequilibrium with other polymorphisms in candidate and neighboring genes known to be associated with lipid metabolism and transport.

Association of a DNA polymorphism of the apolipoprotein AI-CIII-AIV gene cluster with myocardial infarction in a Tunisian population

BACKGROUND

Apolipoproteins AI-CIII-AIV play important roles in the metabolism of triglycerides and high-density lipoprotein cholesterol. However, whether genetic variations in the ApoAI-CIII-AIV gene cluster are associated with the risk of myocardial infarction (MI) remains uncertain. In the present study, we examined a possible association of the ApoCIII SacI polymorphism in the ApoAI-CIII-AIV gene cluster with lipid parameters and MI in a sample of the Tunisian population.

METHODS

A total of 326 Tunisian patients with MI and 361 controls were included in the study. Genotypes were determined by polymerase chain reaction--restriction fragment length polymorphism (PCR-RFLP) analysis.

RESULTS

A significant difference in genotype distribution and allele frequency was observed between patients and controls. At the multivariate analysis after adjustment for traditional vascular risk factors, the ApoCIII SacI polymorphism was significantly associated with MI, according to co-dominant and dominant models (co-dominant model odds ratio [OR]: 1.53, 95% confidence interval [CI]: 1.0-2.35, p=0.04; dominant model OR: 2.02, 95% CI: 1.11-3.67, p=0.02). The MI patient group showed a significant higher frequency of the S2 allele compared to the controls (10.2% vs. 6.5%; OR: 1.64, 95% CI: 1.10-2.47, p=0.01). There was no statistically significant association between ApoAI-CIII-AIV cluster gene polymorphism and lipid, lipoprotein, and apolipoprotein levels in both MI patients and controls.

CONCLUSION

In the current study, a significant association between the ApoCIII SacI polymorphism (presence of S2 allele) and MI in the Tunisian population was found.

Egg consumption as part of an energy-restricted high-protein diet improves blood lipid and blood glucose profiles in individuals with type 2 diabetes

The role of dietary cholesterol in people with diabetes has been little studied. We investigated the effect of a hypoenergetic high-protein high-cholesterol (HPHchol) diet compared to a similar amount of animal protein (high-protein low-cholesterol, HPLchol) on plasma lipids, glycaemic control and cardiovascular risk markers in individuals with type 2 diabetes. A total of sixty-five participants with type 2 diabetes or impaired glucose tolerance (age 54·4 (sd8·2) years; BMI 34·1 (sd4·8) kg/m2; LDL-cholesterol (LDL-C) 2·67 (sd0·10) mmol/l) were randomised to either HPHchol or HPLchol. Both hypoenergetic dietary interventions (6–7 MJ; 1·4–1·7 Mcal) and total carbohydrate:protein:fat ratio of 40:30:30 % were similar but differed in cholesterol content (HPHchol, 590 mg cholesterol; HPLchol, 213 mg cholesterol). HPHchol participants consumed two eggs per d, whereas HPHchol participants replaced the eggs with 100 g of lean animal protein. After 12 weeks, weight loss was 6·0 (sd0·4) kg (P < 0·001). LDL-C and homocysteine remained unchanged. All the subjects reduced total cholesterol ( − 0·3 (sd0·1) mmol/l,P < 0·001), TAG ( − 0·4 (sd0·1) mmol/l,P < 0·001), non-HDL-cholesterol (HDL-C, − 0·4 (sd0·1) mmol/l,P < 0·001), apo-B ( − 0·04 (sd0·02) mmol/l,P < 0·01), HbA1c ( − 0·6 (sd0·1) %,P < 0·001), fasting blood glucose ( − 0·5 (sd0·2) mmol/l,P < 0·01), fasting insulin ( − 1·7 (sd0·7) mIU/l,P < 0·01), systolic blood pressure ( − 7·6 (sd1·7) mmHg,P < 0·001) and diastolic blood pressure ( − 4·6 (sd1·0) mmHg;P < 0·001). Significance was not altered by diet, sex, medication or amount of weight loss. HDL-C increased on HPHchol (+0·02 (sd0·02) mmol/l) and decreased on HPLchol ( − 0·07 (sd0·03) mmol/l,P < 0·05). Plasma folate and lutein increased more on HPHchol (P < 0·05). These results suggest that a high-protein energy-restricted diet high in cholesterol from eggs improved glycaemic and lipid profiles, blood pressure and apo-B in individuals with type 2 diabetes.

Interactions of the apolipoprotein C-III 3238C>G polymorphism and alcohol consumption on serum triglyceride levels

Background

Both apolipoprotein (Apo) C-III gene polymorphism and alcohol consumption have been associated with increased serum triglyceride (TG) levels, but their interactions on serum TG levels are not well known. The present study was undertaken to detect the interactions of the ApoC-III 3238C>G (rs5128) polymorphism and alcohol consumption on serum TG levels.

Methods

A total of 516 unrelated nondrinkers and 514 drinkers aged 15-89 were randomly selected from our previous stratified randomized cluster samples. Genotyping of the ApoC-III 3238C>G was performed by polymerase chain reaction and restriction fragment length polymorphism combined with gel electrophoresis, and then confirmed by direct sequencing. Interactions of the ApoC-III 3238C>G genotype and alcohol consumption was assessed by using a cross-product term between genotypes and the aforementioned factor.

Results

Serum total cholesterol (TC), TG, high-density lipoprotein cholesterol (HDL-C), ApoA-I and ApoB levels were higher in drinkers than in nondrinkers (P < 0.05-0.001). There was no significant difference in the genotypic and allelic frequencies between the two groups. Serum TG levels in nondrinkers were higher in CG genotype than in CC genotype (P < 0.01). Serum TC, TG, low-density lipoprotein cholesterol (LDL-C) and ApoB levels in drinkers were higher in GG genotype than in CC or CG genotype (P < 0.01 for all). Serum HDL-C levels in drinkers were higher in CG genotype than in CC genotype (P < 0.01). Serum TC, TG, HDL-C and ApoA-I levels in CC genotype, TC, HDL-C, ApoA-I levels and the ratio of ApoA-I to ApoB in CG genotype, and TC, TG, LDL-C, ApoA-I and ApoB levels in GG genotype were higher in drinkers than in nondrinkers (P < 0.05-0.01). But the ratio of ApoA-I to ApoB in GG genotype was lower in drinkers than in nondrinkers (P < 0.01). Multivariate logistic regression analysis showed that the levels of TC, TG and ApoB were correlated with genotype in nondrinkers (P < 0.05 for all). The levels of TC, LDL-C and ApoB were associated with genotype in drinkers (P < 0.01 for all). Serum lipid parameters were also correlated with age, sex, alcohol consumption, cigarette smoking, blood pressure, body weight, and body mass index in both groups.

Conclusions

This study suggests that the ApoC-III 3238CG heterozygotes benefited more from alcohol consumption than CC and GG homozygotes in increasing serum levels of HDL-C, ApoA-I, and the ratio of ApoA-I to ApoB, and lowering serum levels of TC and TG.

Dietary cholesterol from eggs increases plasma HDL cholesterol in overweight men consuming a carbohydrate-restricted diet

Carbohydrate-restricted diets (CRD) significantly decrease body weight and independently improve plasma triglycerides (TG) and HDL cholesterol (HDL-C). Increasing intake of dietary cholesterol from eggs in the context of a low-fat diet maintains the LDL cholesterol (LDL-C)/HDL-C for both hyper- and hypo-responders to dietary cholesterol. In this study, 28 overweight/obese male subjects (BMI = 25-37 kg/m2) aged 40-70 y were recruited to evaluate the contribution of dietary cholesterol from eggs in a CRD. Subjects were counseled to consume a CRD (10-15% energy from carbohydrate) and they were randomly allocated to the EGG group [intake of 3 eggs per day (640 mg/d additional dietary cholesterol)] or SUB group [equivalent amount of egg substitute (0 dietary cholesterol) per day]. Energy intake decreased in both groups from 10,243 +/- 4040 to 7968 +/- 2401 kJ (P < 0.05) compared with baseline. All subjects irrespective of their assigned group had reduced body weight and waist circumference (P < 0.0001). Similarly, the plasma TG concentration was reduced from 1.34 +/- 0.66 to 0.83 +/- 0.30 mmol/L after 12 wk (P < 0.001) in all subjects. The plasma LDL-C concentration, as well as the LDL-C:HDL-C ratio, did not change during the intervention. In contrast, plasma HDL-C concentration increased in the EGG group from 1.23 +/- 0.39 to 1.47 +/- 0.38 mmol/L (P < 0.01), whereas HDL-C did not change in the SUB group. Plasma glucose concentrations in fasting subjects did not change. Eighteen subjects were classified as having the metabolic syndrome (MetS) at the beginning of the study, whereas 3 subjects had that classification at the end. These results suggest that including eggs in a CRD results in increased HDL-C while decreasing the risk factors associated with MetS.