Effect of an isoenergetic traditional Mediterranean diet on apolipoprotein A-I kinetic in men with metabolic syndrome

Dietary, macronutrient, micronutrient, and nutrigenetic factors impacting cardiovascular risk markers apolipoprotein B and apolipoprotein A1: a narrative review

Genetic predisposition and dietary factors can impact cardiovascular disease (CVD) risk. Two important markers in assessing CVD risk are apolipoprotein (apo) B and apolipoprotein A1 plasma levels. These markers are measured as a ratio, with a high apoB:apoA1 ratio associated with increased CVD risk. Dietary and lifestyle recommendations are the cornerstone of managing primary and secondary CVD risk-mitigation strategies. One way to assess the impact of various dietary and lifestyle interventions on CVD risk is to evaluate the changes in CVD risk markers, such as apoB, apoA1, and apoB:apoA1 ratio. Various human studies have demonstrated the impact of dietary, macronutrient, and micronutrient interventions on apoB and apoA1 status. This review aims to elucidate dietary, macronutrient, micronutrient, and nutrigenetic considerations for impacting apoB and apoA1 levels. A low-carbohydrate, high-saturated-fat diet, low fiber intake, low vitamin and mineral intake, and zinc and iron deficiency are associated with an elevated apoB:apoA1 ratio. The Mediterranean diet, vegan diet, fermented dairy products, lower sugar intake, higher protein intake, higher polyunsaturated fat intake, and an omega-3-rich diet are associated with a decreased apoB:apoA1 ratio. Micronutrients associated with a decreased apoB:apoA1 ratio include vitamin D sufficiency, increased serum vitamin C, and magnesium. Variants in the APOE, APOA1, and FADS2 genes may alter the apoB:apoA1 ratio in response to various dietary interventions. When accounting for factors that may favorably alter the apoB:apoA1 ratio, researchers should consider a healthy diet sufficient in polyunsaturated fats, vitamins, minerals, trace minerals, and lower excess sugars.

Dietary fat and carbohydrate affect the metabolism of protein-based high-density lipoprotein subspecies

PURPOSE OF REVIEW

Dietary fat compared to carbohydrate increases the plasma concentration of high-density lipoprotein (HDL)-cholesterol. However, neither the mechanism nor its connection to cardiovascular disease is known.

RECENT FINDINGS

Protein-based subspecies of HDL, especially those containing apolipoprotein E (apoE) or apolipoprotein C3 (apoC3), offer a glimpse of a vast metabolic system related to atherogenicity, coronary heart disease (CHD) and other diseases. ApoE stimulates several processes that define reverse cholesterol transport through HDL, specifically secretion of active HDL subspecies, cholesterol efflux to HDL from macrophages involved in atherogenesis, size enlargement of HDL with cholesterol ester, and rapid clearance from the circulation. Dietary unsaturated fat stimulates the flux of HDL that contains apoE through these protective pathways. Effective reverse cholesterol transport may lessen atherogenesis and prevent disease. In contrast, apoC3 abrogates the benefit of apoE on reverse cholesterol transport, which may account for the association of HDL that contains apoC3 with dyslipidemia, obesity and CHD.

SUMMARY

Dietary unsaturated fat and carbohydrate affect the metabolism of protein-defined HDL subspecies containing apoE or apoC3 accelerating or retarding reverse cholesterol transport, thus demonstrating new mechanisms that may link diet to HDL and to CHD.

Effect of varying quantities of lean beef as part of a Mediterranean-style dietary pattern on lipids and lipoproteins: a randomized crossover controlled feeding trial

BACKGROUND

It remains unclear whether red meat consumption is causatively associated with cardiovascular disease (CVD) risk, and few randomized controlled studies have examined the effect of incorporating lean beef into a healthy dietary pattern.

OBJECTIVES

To evaluate the effects of a Mediterranean (MED) diet (carbohydrate 42%, protein 17%, fat 41%, SFAs 8%, MUFAs 26%, PUFAs 8%) with 14 (MED0.5; 0.5 oz), 71 (MED2.5; 2.5 oz), and 156 (MED5.5; 5.5 oz) g/d/2000 kcal lean beef compared with an average American diet (AAD; carbohydrate 52%, protein 15%, fat 33%, SFAs 12%, MUFAs 13%, PUFAs 8%) on lipid and lipoprotein concentrations, particle number, and size.

METHODS

This was a multicenter, 4-period controlled feeding, randomized crossover study. Fifty-nine generally healthy males and females (BMI 20-38 kg/m2; age 30-65 y) consumed each diet for 4 wk with a ≥1-wk washout between the diets. Fasting blood samples were collected at baseline and at the end of each 4-wk period. Lipid subfractions were measured by NMR.

RESULTS

Compared with the AAD, all 3 MED diets decreased LDL cholesterol (MED0.5: -10.3 mg/dL; 95% CI: -5.4, -15.7 mg/dL; MED2.5: -9.1 mg/dL; 95% CI: -3.9, -14.3 mg/dL; MED5.5: -6.9 mg/dL; 95% CI: -1.7, -12.1 mg/dL; P < 0.0001). All MED diets elicited similar reductions in total LDL particle number compared with baseline (P < 0.005); however, significant decreases only occurred with MED0.5 (-91.2 nmol/L; 95% CI: -31.4, -151.0 nmol/L) and MED2.5 (-85.3 nmol/L; 95% CI: -25.4, -145.2 nmol/L) compared with AAD (P < 0.003). Compared with the AAD, non-HDL cholesterol (P < 0.01) and apoB (P < 0.01) were lower following the 3 MED diets; there were no differences between the MED diets. All diets reduced HDL-cholesterol and HDL particle number from baseline (P < 0.01).

CONCLUSIONS

Lipid and lipoprotein lowering was not attenuated with the inclusion of lean beef in amounts ≤71 g (2.5 oz)/d as part of a healthy low-saturated-fat Mediterranean-style diet.This study is registered at clinicaltrials.gov as NCT02723617.

Low-Fat Diet Designed for Weight Loss But Not Weight Maintenance Improves Nitric Oxide-Dependent Arteriolar Vasodilation in Obese Adults

Obesity is associated with microvascular dysfunction. While low-fat diet improves cardiovascular risk, its contributions on microvascular function, independent of weight loss, is unknown. We tested the hypothesis that nitric oxide (NO)-dependent vasodilation in microvessels is improved by low-fat diets designed for weight loss (LFWL) compared to low-fat weight maintenance (LFWM) diet. Obese adults were randomly assigned to either a LFWL diet (n = 11) or LFWM diet (n = 10) for six weeks. Microvessels were obtained from gluteal subcutaneous fat biopsies before and after the intervention for vascular reactivity measurements to acetylcholine (Ach) and flow, with and without L-NAME or indomethacin. Vascular and serum NO and C-reactive protein (CRP) were also measured. LFWL diet increased flow-induced (FID) and ACh-induced dilation (AChID); an effect that was inhibited by L-NAME. Conversely, LFWM diet did not affect FID or AChID. Indomethacin improved FID and AChID in the baseline and this effect was minimized in response to both diets. Serum NO or CRP did not change in response to either diet. In conclusion, LFWL diet improves microvascular reactivity compared to LFWM diet and increased vascular NO contribution to the improved microvascular dilation. These data suggest that weight reduction on low fat diet is critical for microvascular health.

Gender differences in lifestyle and risk factors of metabolic syndrome: Do women have better health habits than men?

AIMS AND OBJECTIVES

To examine the gender-specific lifestyles of adults with metabolic syndrome in the Taiwanese community.

BACKGROUND

Many studies show different prevalence of metabolic syndrome in males and females; however, few studies have investigated gender-specific lifestyle risk factors, which are important for effectively reducing prevalence.

DESIGN

A cross-sectional study design was used.

METHODS

Between 2012 and 2015, a total of 1,066 individuals were recruited in northern Taiwan. Data were collected by questionnaires and analysed by descriptive statistics, chi-square tests and logistic regression. This study followed the STROBE guidelines.

RESULTS

The prevalence of metabolic syndrome was 40.8% in men and 36.0% in women. Women had healthier dietary habits, a higher rate of moderate-vigorous physical activity, and a lower rate of smoking and obesity than men. Men, who were overweight or obese, lacked vigorous physical activity, often consumed excess amounts of salt and fat, and seldom consumed appropriate amounts of protein tended to have metabolic syndrome. Women with an unhealthy metabolism tended to be overweight or obese and seldom consumed dairy products.

CONCLUSIONS

Men, who had normal body weight, performed vigorous physical activity, seldom consumed excess amounts of salt and fat, and often consumed appropriate amounts of protein tended not to have metabolic syndrome. Women with a healthy metabolism were of normal body weight and often consumed dairy products. There exist gender differences in health habits with metabolic syndrome.

RELEVANCE TO CLINICAL PRACTICE

Although the associated risk factors differed between men and women, controlling body weight and maintaining a healthy lifestyle may reduce the risk of metabolic syndrome.

Olive oil phenolic compounds and high-density lipoprotein function

PURPOSE OF REVIEW

The functional capacities of high-density lipoproteins (HDLs) reflect the physiological role of the particle better than the quantity of HDL cholesterol. Owing to its phenolic compounds, the consumption of virgin olive oil has emerged as a promising therapy to promote these capacities. This review highlights the human studies that explain these benefits and explores some possible mechanisms.

RECENT FINDINGS

The consumption of olive oil phenolic compounds increased the ability of HDLs to pick up cholesterol excess in peripheral cells (the cholesterol efflux capacity). Olive oil phenolic compounds have also been shown to improve HDL antioxidant capacities and some anti-inflammatory traits. These changes respond to an improvement of HDL oxidative status and composition.

SUMMARY

Novel strategies to increase HDL functional capacities are in demand from clinicians. The attainment of a fully-functional HDL through dietary or lifestyle changes is a priority in cardiovascular research. Within this context, the consumption of virgin olive oil, because of its phenolic compounds, may be a relevant protective approach. Further studies in large-scale, randomized controlled trials are, however, required to confirm these effects in HDL functionality.

Greater adherence to a Mediterranean dietary pattern is associated with improved plasma lipid profile: the Aragon Health Workers Study cohort

INTRODUCTION AND OBJECTIVES

There is wide recognition of the importance of healthy eating in cardiovascular health promotion. The purpose of this study was to identify the main dietary patterns among a Spanish population, and to determine their relationship with plasma lipid profiles.

METHODS

A cross-sectional analysis was conducted of data from 1290 participants of the Aragon Workers Health Study cohort. Standardized protocols were used to collect clinical and biochemistry data. Diet was assessed through a food frequency questionnaire, quantifying habitual intake over the past 12 months. The main dietary patterns were identified by factor analysis. The association between adherence to dietary patterns and plasma lipid levels was assessed by linear and logistic regression.

RESULTS

Two dietary patterns were identified: a Mediterranean dietary pattern, high in vegetables, fruits, fish, white meat, nuts, and olive oil, and a Western dietary pattern, high in red meat, fast food, dairy, and cereals. Compared with the participants in the lowest quintile of adherence to the Western dietary pattern, those in the highest quintile had 4.6 mg/dL lower high-density lipoprotein cholesterol levels (P < .001), 8 mg/dL lower apolipoprotein A1 levels (P = .005) and a greater risk of having decreased high-density lipoprotein cholesterol (odds ratio = 3.19; 95% confidence interval, 1.36-7.5; P-trend = .03). Participants adhering to the Mediterranean dietary pattern had 3.3mg/dL higher high-density lipoprotein cholesterol levels (P < .001), and a ratio of triglycerides to high-density lipoprotein cholesterol that was 0.43 times lower (P = .043).

CONCLUSIONS

Adherence to the Mediterranean dietary pattern is associated with improved lipid profile compared with a Western dietary pattern, which was associated with a lower odds of optimal high-density lipoprotein cholesterol levels in this population.

Dietary fatty acids, dietary patterns, and lipoprotein metabolism

PURPOSE OF REVIEW

Few studies have reviewed the impact of dietary fat and dietary patterns on lipoprotein metabolism. This review intends to provide perspective on this topic, while focusing primarily on the studies that assessed intravascular lipoprotein kinetics in humans using isotope methodologies.

RECENT FINDINGS

Data suggest that dietary saturated fatty acids slow the clearance of LDL apolipoprotein (apo)B-100 and of apoA-I from the circulation, whereas possibly increasing also apoA-I production. Dietary trans fats reduce the clearance of LDL apoB-100, whereas increasing the clearance of apoA-I. n-3 polyunsaturated fatty acids (PUFAs) intake reduces the production of apoB-48-containing lipoproteins as well as of VLDL apoB-100 and increases their conversion into smaller lipoproteins. Medium-chain triglycerides appear to have no significant effect on lipoprotein kinetics. Finally, Mediterranean diet in the absence of weight loss reduces LDL cholesterol, primarily by enhancing its clearance from the circulation.

SUMMARY

Kinetic studies with tracers allow a better appreciation of the impact of specific dietary factors on plasma lipid risk factors. However, additional studies are required to better document the effect of monounsaturated fatty acids, n-6 PUFAs, and of whole diets on lipoprotein metabolism.

Effect of Mediterranean Diet With and Without Weight Loss on Apolipoprotein B 100 Metabolism in Men With Metabolic Syndrome

Objective—

To assess the effect of a Mediterranean diet (MedDiet) with and without weight loss (WL) on apolipoprotein B 100 (apoB 100 ) metabolism in men with metabolic syndrome.

Approach and Results—

The diet of 19 men with metabolic syndrome (age, 24–62 years) was first standardized to a North American isoenergetic control diet for 5 weeks, followed by an isoenergetic MedDiet for an additional 5 weeks under full-feeding conditions (MedDiet−WL). Participants next underwent a 20-week supervised WL program under free-living conditions (−10.2±2.9% body weight; P <0.01) and finally consumed the MedDiet (5 weeks) under weight-stabilizing feeding conditions (MedDiet+WL). In vivo kinetic of apoB 100 was assessed in the fasted state at the end of the 3 controlled diets using a bolus of D 3 -leucine. Compared with the control diet, MedDiet−WL reduced low-density lipoprotein (LDL)-apoB 100 pool size (−14.2%, P <0.01) primarily through an increase in LDL-apoB 100 fractional catabolic rate (+30.4%, P =0.02) and increased LDL particle size ( P <0.01) but had no effect on very-LDL (VLDL)-apoB 100 pool size or triglyceride concentrations, despite a significant increase in VLDL-apoB 100 fractional catabolic rate (+25.6%; P =0.03). MedDiet+WL had no further effect on LDL-apoB 100 pool size and fractional catabolic rate but further increased LDL particle size and reduced VLDL-apoB 100 pool size versus the control diet primarily through an increase in VLDL-apoB 100 fractional catabolic rate (+30.7%; P <0.01).

Conclusions—

Consumption of MedDiet increases LDL size and reduces LDL-apoB 100 concentrations primarily by increasing the catabolism of LDL even in the absence of WL in men with metabolic syndrome. MedDiet seems to have a trivial effect on VLDL concentrations and kinetics unless accompanied by significant WL.

Clinical Trial Registration

—URL: http://www.clinicaltrials.gov . Unique identifier: NCT00988650.