Apolipoprotein E isoforms 3/3 and 3/4 differentially interact with circulating stearic, palmitic, and oleic fatty acids and lipid levels in Alaskan Natives

Impact of APOE Alleles-by-Diet Interactions on Glycemic and Lipid Features- A Cross-Sectional Study of a Cohort of Type 2 Diabetes Patients from Western Mexico: Implications for Personalized Medicine

Purpose

To analyze clinically relevant interactions between the apolipoprotein E (APOE) ε2, ε3 and ε4 alleles and nutritional factors on glycemic control and lipid levels in a cohort of type 2 diabetes (T2D) patients from western Mexico.

Patients and Methods

In this cross-sectional study of the cohort of T2D patients, a total of 224 individuals were selected for interaction studies. Clinical and anthropometric data were obtained from pre-designed medical records. Dietary intake was assessed by validated three-day food consumption records. Biochemical measurements were determined by automated methods. APOE genotyping was performed by a real-time allelic discrimination assay. Gene–diet interactions were tested by corrected multiple linear regression analyses, which were adjusted by potential confounding factors such as age, sex, energy intake, BMI and anti-hyperglycemic therapy (Metformin, Glibenclamide or Insulin), and years with T2D.

Results

Seventy-six percent of patients with T2D were on Metformin therapy. The frequencies of the APOE alleles were ε2 (5.8%), ε3 (74.1%) and ε4 (20.1%). After statistical settings, significant APOE alleles-by-diet interactions in relation to the metabolic profile were found. Interestingly, higher blood levels of total cholesterol (p int. = 0.016), non-HDL-c (p int. = 0.024), and LDL-c (p int. = 0.030) were found only in carriers of the APOE ε2 allele with a low consumption of MUFA. In contrast, carriers of the APOE ε4 allele with a high ω-6:ω-3 PUFA ratio in the diet had higher %HbA1c blood concentrations (p int. = 0.035).

Conclusion

This study suggests a differential metabolic impact of APOE alleles on lipid/glycemic phenotypes depending on the dietary intake, with important potential implications in the personalized medicine and nutritional management of patients with type 2 diabetes mellitus.

Lipoxins, RevD1 and 9, 13 HODE as the most important derivatives after an early incident of ischemic stroke

There is limited information available regarding the association of plasma free fatty acids (FFA) and inflammation mediators with ischemic stroke. At the same time, new treatment strategies are being pursued. The aim of this study was to carry out a thorough analysis of inflammation with multiple FFA-derivative mediators after and ischemic stroke and standard treatment. HPLC separations of 17 eicosanoids were performed using an Agilent Technologies 1,260 liquid chromatograph. The profiles of the esters of fatty acids were labelled by means of gas chromatography. FFA, and eicosanoid profiles in the group of patients after ischemic stroke significantly differed from the profile of the control group. Studies confirmed the involvement of derivative synthesis pathways responsible for the inflammation, especially palmitic acid (9 and 13 HODE), arachidonic acid, EPA and DHA. Arachidonic acid derivatives were synthesised on 5LOX, 15 LOX and COX pathways with the participation of prostaglandins while omega 3 derivatives strengthened the synthesis of resolvins, RevD1 in particular. The ability to accelerate the quenching of inflammation after ischemic stroke seems to be a promising strategy of stroke treatment in its early stage. In this context, our study points to lipoxins, RevD1, and 9, 13 HODE as the most important derivatives.

APOE and the Association of Fatty Acids With the Risk of Stroke, Coronary Heart Disease, and Mortality

Background and Purpose- The role of dietary fat on cardiovascular health and mortality remains under debate. Because the APOE is central to the transport and metabolism of lipids, we examined associations between plasma fatty acids and the risk of stroke, coronary heart disease, and mortality by APOE-ε4 genotype. Methods- We included 943 FHS (Framingham Heart Study) and 1406 3C (Three-City) Bordeaux Study participants. Plasma docosahexaenoic, linoleic, arachidonic, and palmitic fatty acids were measured at baseline by gas chromatography. All-cause stroke, ischemic stroke, coronary heart disease, and all-cause mortality events were identified prospectively using standardized protocols. Each cohort used Cox models to separately relate fatty acid levels to the risk of developing each event during ≤10 years of follow-up adjusting for potential confounders and stratifying by APOE genotype (ε4 carriers versus noncarriers). We then meta-analyzed summary statistics using random-effects models. Results- On average, participants had a mean age of 74 years, 61% were women, and 21% (n=483) were APOE-ε4 carriers. Meta-analysis results showed that, only among APOE-ε4 carriers, every SD unit increase in linoleic acid was associated with a reduced risk of all-cause stroke (hazard ratio [HR], 0.54 [95% CI, 0.38-0.78]), ischemic stroke (HR, 0.48 [95% CI, 0.33-0.71]), and all-cause mortality (HR, 0.70 [95% CI, 0.57-0.85]). In contrast, every SD unit increase in palmitic acid was related to an increased risk of all-cause stroke (HR, 1.58 [95% CI, 1.16-2.17]), ischemic stroke (HR, 1.76 [95% CI, 1.26-2.45]), and coronary heart disease (HR, 1.48 [95% CI, 1.09-2.01]), also in APOE-ε4 carriers only. Results for docosahexaenoic acid and arachidonic acid were heterogeneous between cohorts. Conclusions- These exploratory results suggest that APOE-ε4 carriers may be more susceptible to the beneficial or adverse impact of fatty acids on cardiovascular disease and mortality. In this subgroup, higher linoleic acid was protective for stroke and mortality, whereas palmitic acid was a risk factor for stroke and coronary heart disease. The mechanisms underlying these novel findings warrant further investigation.

APOE4 Genotype Exerts Greater Benefit in Lowering Plasma Cholesterol and Apolipoprotein B than Wild Type (E3/E3), after Replacement of Dietary Saturated Fats with Low Glycaemic Index Carbohydrates

We examined the impact of APOE genotype on plasma lipids and glucose in a secondary analysis of data from a five-arm, randomised controlled, parallel dietary intervention trial ('RISCK' study), to investigate the impact of replacing saturated fatty acids (SFA) with either monounsaturated fat (MUFA) or carbohydrate of high or low glycaemic index (GI) on CVD risk factors and insulin sensitivity. We tested the impact of APOE genotype (carriage of E2 and E4 alleles versus E3/E3), determined retrospectively, on plasma lipids, lipoproteins and glucose homeostasis at baseline (n = 469), and on the change in these variables after 24 weeks of dietary intervention (n = 389). At baseline, carriers of E2 (n = 70), E4 (n = 125) and E3/E3 (n = 274) expressed marked differences in total plasma cholesterol (TC, p = 0.001), low density lipoprotein cholesterol (LDL-C, p < 0.0001), apolipoprotein B (apo B, p < 0.0001) and total to high density lipoprotein cholesterol ratio (TC:HDL-C, p = 0.002), with plasma concentrations decreasing in the order E4 > E3/E3 > E2. Following intervention, there was evidence of a significant diet x genotype interaction with significantly greater decreases in TC (p = 0.02) and apo B (p = 0.006) among carriers of E4 when SFA was replaced with low GI carbohydrate on a lower fat diet (TC -0.28 mmol/L p = 0.03; apo B -0.1 g/L p = 0.02), and a relative increase in TC (in comparison to E3/E3) when SFA was replaced with MUFA and high GI carbohydrates (TC 0.3 mmol/L, p = 0.03). Among carriers of E2 (compared with E3/E3) there was an increase in triacylglycerol (TAG) when SFA was replaced with MUFA and low GI carbohydrates 0.46 mmol/L p = 0.001). There were no significant interactions between APOE genotype and diet for changes in indices of glucose homeostasis. In conclusion, variations in APOE genotype led to differential effects on the lipid response to the replacement of SFA with MUFA and low GI carbohydrates.

Apolipoproteins C-II and C-III as nutritional markers unaffected by inflammation

BACKGROUND

Rapid turnover proteins (RTPs), such as transthyretin (TTR), retinol binding protein (RBP), and transferrin (Tf), provide an accurate assessment of nutritional status but are susceptible to inflammation. Lipid-related markers, which have short half-lives in serum, may be better suited for nutritional assessment. We sought to identify sensitive nutritional markers unaffected by inflammation.

METHODS

Fasting serum samples were collected from 30 malnourished inpatients and 25 healthy volunteers. Malnourished inpatients were divided into 2 groups: a low-C-reactive protein (CRP) group (CRP < 20 mg/l, n = 15) and a high-CRP group (CRP ≥ 20 mg/l, n = 15). Lipid-related markers, traditional nutritional markers, RTPs, micronutrients, and ketone bodies were measured and compared among the groups.

RESULTS

Apolipoprotein (Apo)C-II and ApoC-III concentrations were lower in malnourished inpatients than in the control group. There was no significant difference in ApoC-II and ApoC-III between the low- and high-CRP groups. Carnitine transporters and ketone bodies did not show a significant difference among the three groups. Albumin, TTR, RBP, and Tf concentrations were lowest in the high-CRP group, intermediate in the low-CRP group, and highest in the control group.

CONCLUSIONS

These results indicate that ApoC-II and ApoC-III are appropriate nutritional biomarkers unaffected by inflammation.