Associations of dairy and fiber intake with circulating odd-chain fatty acids in post-myocardial infarction patients

Validation of Nutritional Approaches to Modulate Cardiovascular and Diabetic Risk Factors in Patients with Hypertriglyceridemia or Prediabetes-The MoKaRi II Randomized Controlled Study

Hypertriglyceridemia and diabetes mellitus type 2 are among the most important metabolic diseases globally. Diet plays a vital role in the development and progression of both clinical pictures. For the 10-week randomized, controlled, intervention study, 67 subjects with elevated plasma triglyceride (TG) concentrations (≥1.7 mmol/L) and 69 subjects with elevated fasting glucose concentrations (≥5.6 < 7.0 mmol/L) were recruited. The intervention groups received specially developed, individualized menu plans and regular counseling sessions to lower (A) TG or (B) fasting glucose and glycated hemoglobin A1c as well as other cardiovascular and diabetic risk factors. The hypertriglyceridemia intervention group was further supplemented with fish oil (3.5 g/d eicosapentaenoic acid + docosahexaenoic acid). The two control groups maintained a typical Western diet. Blood samples were taken every 2 weeks, and anthropometric data were collected. A follow-up examination was conducted after another 10 weeks. In both intervention groups, there were comparable significant reductions in blood lipids, glucose metabolism, and anthropometric parameters. These results were, with a few exceptions, significantly more pronounced in the intervention groups than in the corresponding control groups (comparison of percentage change from baseline). In particular, body weight was reduced by 7.4% (6.4 kg) and 7.5% (5.9 kg), low-density lipoprotein cholesterol concentrations by 19.8% (0.8 mmol/L) and 13.0% (0.5 mmol/L), TG concentrations by 18.2% (0.3 mmol/L) and 13.0% (0.2 mmol/L), and homeostatic model assessment for insulin resistance by 31.8% (1.1) and 26.4% (0.9) (p < 0.05) in the hypertriglyceridemia and prediabetes intervention groups, respectively. Some of these changes were maintained until follow-up. In patients with elevated TG or fasting glucose, implementing individualized menu plans in combination with regular counseling sessions over 10 weeks led to a significant improvement in cardiovascular and diabetic risk factors.

Metabolic profiles reflect weight loss maintenance and the composition of diet after very-low-energy diet

BACKGROUND & AIMS

Diet and weight loss affect circulating metabolome. However, metabolite profiles induced by different weight loss maintenance diets and underlying longer term weight loss maintenance remain unknown. Herein, we investigated after-weight-loss metabolic signatures of two isocaloric 24-wk weight maintenance diets differing in satiety value due to dietary fibre, protein and fat contents and identified metabolite features that associated with successful weight loss maintenance.

METHODS

Non-targeted LC-MS metabolomics approach was used to analyse plasma metabolites of 79 women and men (mean age ± SD 49.7 ± 9.0 years; BMI 34.2 ± 2.5 kg/m2) participating in a weight management study. Participants underwent a 7-week very-low-energy diet (VLED) and were thereafter randomised into two groups for a 24-week weight maintenance phase. Higher satiety food (HSF) group consumed high-fibre, high-protein, and low-fat products, while lower satiety food (LSF) group consumed isocaloric low-fibre products with average protein and fat content as a part of their weight maintenance diets. Plasma metabolites were analysed before the VLED and before and after the weight maintenance phase. Metabolite features discriminating HSF and LSF groups were annotated. We also analysed metabolite features that discriminated participants who maintained ≥10% weight loss (HWM) and participants who maintained <10% weight loss (LWM) at the end of the study, irrespective of the diet. Finally, we assessed robust linear regression between metabolite features and anthropometric and food group variables.

RESULTS

We annotated 126 metabolites that discriminated the HSF and LSF groups and HWM and LWM groups (p < 0.05). Compared to LSF, the HSF group had lower levels of several amino acids, e.g. glutamine, arginine, and glycine, short-, medium- and long-chain acylcarnitines (CARs), odd- and even-chain lysoglycerophospholipids, and higher levels of fatty amides. Compared to LWM, the HWM group in general showed higher levels of glycerophospholipids with a saturated long-chain and a C20:4 fatty acid tail, and unsaturated free fatty acids (FFAs). Changes in several saturated odd- and even-chain LPCs and LPEs and fatty amides were associated with the intake of many food groups, particularly grain and dairy products. Increase in several (lyso)glycerophospholipids was associated with decrease in body weight and adiposity. Increased short- and medium-chain CARs were related to decreased body fat-free mass.

CONCLUSIONS

Our results show that isocaloric weight maintenance diets differing in dietary fibre, protein, and fat content affected amino acid and lipid metabolism. Increased abundances of several phospholipid species and FFAs were related with greater weight loss maintenance. Our findings indicate common and distinct metabolites for weight and dietary related variables in the context of weight reduction and weight management. The study was registered in isrctn.org with identifier 67529475.

Fatty acid composition of cholesterol esters reflects dietary fat intake after dietary interventions in a multinational population

BACKGROUND

The effects of different dietary fatty acids (FA) on cardiovascular risk still needs clarification. Plasma lipids composition may be a biomarker of FA dietary intake.

PURPOSE

To evaluate in a composite population the relationships between changes in dietary fat intake and changes in FA levels in serum cholesterol esters.

METHODS

In a multinational, parallel-design, dietary intervention (KANWU study), dietary intakes (3-day food record) and FA composition of serum cholesterol esters (gas-liquid chromatography) were evaluated at baseline and after 3 months in 162 healthy individuals, randomly assigned to a diet containing a high proportion of saturated (SFA) or monounsaturated (MUFA) fat, with a second random assignment to fish oil or placebo supplements.

RESULTS

Main differences in serum lipid composition after the two diets included saturated (especially myristic, C14:0, and pentadecanoic, C15:0) and monounsaturated (oleic acid, C18:1 n-9) FA. C14:0 and C15:0 were related to SFA intake, while C18:1 n-9 was associated with MUFA intake. Fish oil supplementation induced a marked increase in eicosapentaenoic (C20:5 n-3) and docosahexaenoic (C22:6 n-3) acids. After the 3-month intervention, Δ-9 desaturase activity, calculated as palmitoleic acid/palmitic acid (C16:1/C16:0) ratio, was more reduced after the MUFA (0.31±0.10 vs 0.25±0.09, p<0.0001) than SFA diet (0.31±0.09 vs 0.29±0.08, p=0.006), with a statistically significant difference between the two groups (p<0.0001).

CONCLUSIONS

This study shows that serum cholesterol ester FA composition can be used during randomized controlled trials as an objective indicator of adherence to experimental diets based on saturated and monounsaturated fat modifications, as well as fish oil supplementation.

Dairy products and kidney function decline after myocardial infarction: A prospective analysis in the Alpha Omega Cohort

BACKGROUND & AIMS

Population-based studies have shown both beneficial and neutral associations between dairy consumption and kidney function outcomes. We investigated the association between dairy products and kidney function decline in drug-treated post-myocardial infarction (MI) patients.

METHODS

We analysed data of 2169 post-MI patients (aged 60-80 years, 81% male) of the Alpha Omega Cohort. Dietary data were collected at baseline (2002-2006) using a validated 203-item food frequency questionnaire. The 2021 Chronic Kidney Disease Epidemiology (CKD-EPI) equation was used to estimate 40-months change in creatinine-cystatin C based glomerular filtration rate (eGFR_cr-cysC, mL/min per 1.73 m²). Beta coefficients and 95% confidence intervals (CIs) for dairy products in relation to annual eGFR_cr-cysC change were obtained from multivariable linear regression, adjusted for age, sex, energy intake, and other lifestyle and dietary factors.

RESULTS

Baseline energy-adjusted median intakes were 64 g/day for total milk, 20 g/day for hard cheeses, 18 g/day for plain yogurt, and 70 g/day for dairy desserts. Mean ± SD eGFR_cr-cysC was 84 ± 20 (13% with CKD), and annual eGFR_cr-cysC change was -1.71 ± 3.85. In multivariable models, high vs. low intakes of total milk, cheese, and dairy desserts were not associated with annual eGFR_cr-cysC change (β_{total milk}: -0.21 [-0.60; 0.19], β_cheese: -0.08 [-0.52; 0.36], β_{dairy desserts}: -0.24 [-0.72; 0.24]). High vs. low intake of yogurt was adversely associated with annual eGFR_cr-cysC change (β_{total yogurt}: -0.50 [-0.91;-0.09]), but subsequent spline analyses showed no clear dose-response association.

CONCLUSIONS

Intakes of milk, cheese or dairy desserts were not associated with a delayed kidney function decline after MI. The observed adverse association for yogurt should be interpreted with caution. Our findings require confirmation in other cohorts of coronary heart disease patients.

Graduate Student Literature Review: A scoping review on the impact of consumption of dairy products on phosphatidylcholine and lysophosphatidylcholine in circulation and the liver in human studies and animal models

Dairy consumption is inversely related to the risk of developing type 2 diabetes in epidemiological research. One proposed hypothesis is that phospholipid (PL) species associated with dairy consumption mediate this relationship. This scoping review aimed to identify the existing literature in animal and human trials investigating the impact of dairy products, including milk, yogurt, and cheese as well as dairy-derived PL supplementation on PL and its species in the circulation, summarizing the characteristics of these studies and identifying research gaps. A systematic search was conducted across 3 databases (PubMed, Scopus, and Web of Science) in March 2021. Of 2,427 identified references, 15 studies (7 humans and 8 animal studies) met the eligibility criteria and were included in the final narrative synthesis. The evidence base was heterogeneous, involving a variety of clinical and preclinical studies, metabolically healthy or obese/diabetic participants or animal models, and displayed mixed findings. Circulating postprandial concentrations of total PL were elevated acutely but unchanged after longer intervention with dairy products. The PL concentration remained stable even after a high dosage of milk supplemented with dairy-derived PL, which may be related to increased fecal excretion; however, certain phosphatidylcholine (PC) or lysophosphatidylcholine species were increased in circulation by interventions. These include several PC species with 32 to 38 total carbons in addition to the dairy biomarkers C15:0 and C17:0. The results of this scoping review demonstrate a small body of literature indicating that dairy products can influence blood concentrations of PC and lysophosphatidylcholine species in both rodents and humans without alteration of total PL and PC. There is a lack of well-designed trials in humans and animals that explore the potential differences between individual dairy foods on PL species. In addition, trials to understand the bioactive properties of PC and lysophosphatidylcholine species on cardiometabolic risk are needed.

Nutritional lipidomics for the characterization of lipids in food

Lipids represent one out of three major macronutrient classes in the human diet. It is estimated to account for about 15-20% of the total dietary intake. Triacylglycerides comprise the majority of them, estimated 90-95%. Other lipid classes include free fatty acids, phospholipids, cholesterol, and plant sterols as minor components. Various methods are used for the characterization of nutritional lipids, however, lipidomics approaches become increasingly attractive for this purpose due to their wide coverage, comprehensiveness and holistic view on composition. In this chapter, analytical methodologies and workflows utilized for lipidomics profiling of food samples are outlined with focus on mass spectrometry-based assays. The chapter describes common lipid extraction protocols, the distinct instrumental mass-spectrometry based analytical platforms for data acquisition, chromatographic and ion-mobility spectrometry methods for lipid separation, briefly mentions alternative methods such as gas chromatography for fatty acid profiling and mass spectrometry imaging. Critical issues of important steps of lipidomics workflows such as structural annotation and identification, quantification and quality assurance are discussed as well. Applications reported over the period of the last 5years are summarized covering the discovery of new lipids in foodstuff, differential profiling approaches for comparing samples from different origin, species, varieties, cultivars and breeds, and for food processing quality control. Lipidomics as a powerful tool for personalized nutrition and nutritional intervention studies is briefly discussed as well. It is expected that this field is significantly growing in the near future and this chapter gives a short insight into the power of nutritional lipidomics approaches.

Can individual fatty acids be used as functional biomarkers of dairy fat consumption in relation to cardiometabolic health? A narrative review

In epidemiological studies, dairy food consumption has been associated with minimal effect or decreased risk of some cardiometabolic diseases (CMD). However, current methods of dietary assessment do not provide objective and accurate measures of food intakes. Thus, the identification of valid and reliable biomarkers of dairy product intake is an important challenge to best determine the relationship between dairy consumption and health status. This review investigated potential biomarkers of dairy fat consumption, such as odd-chain, trans- and branched-chain fatty acids (FA), which may improve the assessment of full-fat dairy product consumption. Overall, the current use of serum/plasma FA as biomarkers of dairy fat consumption is mostly based on observational evidence, with a lack of well-controlled, dose-response intervention studies to accurately assess the strength of the relationship. Circulating odd-chain SFA and trans-palmitoleic acid are increasingly studied in relation to CMD risk and seem to be consistently associated with a reduced risk of type 2 diabetes in prospective cohort studies. However, associations with CVD are less clear. Overall, adding less studied FA such as vaccenic and phytanic acids to the current available evidence may provide a more complete assessment of dairy fat intake and minimise potential confounding from endogenous synthesis. Finally, the current evidence base on the direct effect of dairy fatty acids on established biomarkers of CMD risk (e.g. fasting lipid profiles and markers of glycaemic control) mostly derives from cross-sectional, animal and in vitro studies and should be strengthened by well-controlled human intervention studies.

Associations of the Lipidome with Ageing, Cognitive Decline and Exercise Behaviours

One of the most recognisable features of ageing is a decline in brain health and cognitive dysfunction, which is associated with perturbations to regular lipid homeostasis. Although ageing is the largest risk factor for several neurodegenerative diseases such as dementia, a loss in cognitive function is commonly observed in adults over the age of 65. Despite the prevalence of normal age-related cognitive decline, there is a lack of effective methods to improve the health of the ageing brain. In light of this, exercise has shown promise for positively influencing neurocognitive health and associated lipid profiles. This review summarises age-related changes in several lipid classes that are found in the brain, including fatty acyls, glycerolipids, phospholipids, sphingolipids and sterols, and explores the consequences of age-associated pathological cognitive decline on these lipid classes. Evidence of the positive effects of exercise on the affected lipid profiles are also discussed to highlight the potential for exercise to be used therapeutically to mitigate age-related changes to lipid metabolism and prevent cognitive decline in later life.

Associations of Maternal Consumption of Dairy Products during Pregnancy with Perinatal Fatty Acids Profile in the EDEN Cohort Study

Maternal diet is the main source of fatty acids for developing offspring in-utero and in breastfed infants. Dairy products (DP) are important sources of fat in the European population diet. C15:0 and C17:0 fatty acids have been suggested as biomarkers of dairy fat consumption. This study’s aim is to describe the associations between maternal DP (milk included) consumption during pregnancy and C15:0, C17:0 and polyunsaturated fatty acid (PUFA) levels in perinatal biofluids. Study populations were composed of 1763, 1337 and 879 French mothers from the EDEN (“Étude des Déterminants pre- et post-natals de la santé de l’ENfant”) study, with data on maternal and cord red blood cells’ (RBC) membrane and colostrum, respectively. Associations were assessed using linear regression models adjusted for recruitment center, maternal age, healthy dietary pattern or fish consumption. Greater adherence to a ”cheese” consumption pattern was associated with lower linoleic acid level in colostrum and higher C15:0 and C17:0 levels but in a less consistent manner for C17:0 across biofluids. Greater adherence to “semi-skimmed milk, yogurt” and “reduced-fat DP” patterns was related to higher docosahexaenoic acid and total n-3 PUFA levels and lower n-6/n-3 long-chain PUFA ratio in maternal and cord RBC. Our results suggest that C15:0 could be a good biomarker of maternal dairy fat consumption in perinatal biofluids.

Association of the odd-chain fatty acid content in lipid groups with type 2 diabetes risk: A targeted analysis of lipidomics data in the EPIC-Potsdam cohort

BACKGROUND

Plasma odd-chain saturated fatty acids (OCFA) are inversely associated with type 2 diabetes (T2D) risk and may serve as biomarkers for dairy fat intake. Their distribution across different lipid classes and consequences for diabetes risk remain unknown.

AIM

To investigate the prospective associations of OCFA-containing lipid species with T2D risk and their dietary determinants.

METHODS

Within the European Prospective Investigation into Cancer and Nutrition-Potsdam study (n = 27,548), we applied a nested case-cohort design (subcohort: n = 1,248; T2D cases: n = 820; median follow-up 6.5 years). OCFA-containing lipids included triacylglycerols, free fatty acids (FFA), cholesteryl esters (CE), phosphatidylcholines, phosphatidylethanolamines, lysophosphatidylcholines, lysophosphatidylethanolamines, monoacylglycerols, and diacylglycerols. We estimated lipid class-specific associations between OCFA-containing lipids and T2D in sex-stratified Cox proportional-hazards models. We investigated correlations between lipids and dietary intakes derived from food-frequency questionnaires.

RESULTS

We observed heterogeneous integration of OCFA in different lipid classes: triacylglycerols, FFA, CE, and phosphatidylcholines contributed most to the total OCFA-plasma abundance. The relative concentration of OCFA was particularly high in monoacylglycerols, and the contribution of C15:0 versus C17:0 to the total OCFA-abundance differed across lipid classes. In women, several OCFA-containing phospholipids were inversely associated with T2D risk [phosphatidylcholine(C15:0), HR Q5 vs Q1: 0.56, 95% CI 0.32-0.97; phosphatidylcholine(C17:0), HR per SD: 0.59, 95% CI 0.48-0.71; lysophosphatidylcholine(C17:0), HR Q5 vs Q1: 0.42, 95% CI 0.23-0.76]. In men, we did not detect statistically significant inverse associations in phospholipids, and lysophosphatidylcholine(C15:0) was associated with higher T2D risk (HR Q5 vs. Q1: 1.96, 95% CI 1.06-3.63). Besides, CE(C17:0), monoacylglycerols(C15:0), and diacylglycerols(C15:0) were inversely associated with T2D risk; FFA(C17:0) was positively associated with T2D risk in women. Consumption of fat-rich dairy and fiber-rich foods were positively and red meat inversely correlated to OCFA-containing lipid plasma levels.

CONCLUSIONS

OCFA-containing lipids are linked to T2D risk in a lipid class and sex-specific manner, and they are correlated with several foods.

Plasma fatty acids and kidney function decline in post-myocardial infarction patients of the Alpha Omega Cohort

BACKGROUND AND AIMS

Age-related kidney function decline is accelerated in patients with coronary heart disease (CHD). CHD and chronic kidney disease may share common etiologies. We examined plasma fatty acids (FAs) as novel biomarkers of kidney function decline after myocardial infarction (MI).

METHODS AND RESULTS

The analysis included 2329 Dutch post-MI patients aged 60-80y (Alpha Omega Cohort) most receiving state-of-the-art medications. Plasma FAs (% total FAs) in cholesteryl esters were assessed at baseline (2002-2006), and ∼40 months change in creatinine-cystatin C based glomerular filtration rate was estimated (eGFR, in ml/min per 1.73 m²). Beta coefficients for annual eGFR change in relation to plasma linoleic acid (LA; 50.1% of total FAs in CE), omega-3 FAs (EPA + DHA; 1.7%), odd-chain FAs (C15:0 and C17:0; 0.2%), and C14:0 (0.7%) were obtained from linear regression analyses adjusted for age, sex, smoking, and alcohol intake. Mean baseline eGFR ±SD was 78.5 ± 18.7, which declined by 4.7 ± 13.1 during follow-up, or 1.4 ± 3.9 per year. The annual decline in eGFR was less in patients with higher plasma LA (adjusted beta: 0.40 for LA >47 vs ≤ 47%, 95% CI: 0.01; 0.78; p = 0.046). Associations of plasma LA with annual eGFR decline were stronger in 437 patients with diabetes (1.21, 0.24; 2.19) and in 402 patients with CKD (eGFR<60; 0.90, -0.09; 1.89). Weaker, non-significant associations with kidney function decline were observed for the other plasma FAs.

CONCLUSION

Higher plasma LA may be a good predictor of less kidney function decline after MI, particularly in patients with diabetes. The Alpha Omega Cohort is registered with clinicaltrials.gov, NCT03192410.

Effect of Microbial Status on Hepatic Odd-Chain Fatty Acids Is Diet-Dependent

Odd-chain fatty acids (OCFA) are inversely associated with type-2-diabetes in epidemiological studies. They are considered as a biomarker for dairy intake because fermentation in ruminants yields high amounts of propionate, which is used as the primer for lipogenesis. Recently, we demonstrated endogenous OCFA synthesis from propionate in humans and mice, but how this is affected by microbial colonization is still unexplored. Here, we investigated the effect of increasing microbiota complexity on hepatic lipid metabolism and OCFA levels in different dietary settings. Germ-free (GF), gnotobiotic (SIH, simplified human microbiota) or conventional (CONV) C3H/HeOuJ-mice were fed a CHOW or high-fat diet with inulin (HFI) to induce microbial fermentation. We found that hepatic lipogenesis was increased with increasing microbiota complexity, independently of diet. In contrast, OCFA formation was affected by diet as well as microbiota. On CHOW, hepatic OCFA and intestinal gluconeogenesis decreased with increasing microbiota complexity (GF > SIH > CONV), while cecal propionate showed a negative correlation with hepatic OCFA. On HFI, OCFA levels were highest in SIH and positively correlated with cecal propionate. The propionate content in the CHOW diet was 10 times higher than that of HFI. We conclude that bacterial propionate production affects hepatic OCFA formation, unless this effect is masked by dietary propionate intake.