Trans-palmitoleic acid, metabolic risk factors, and new-onset diabetes in U.S. adults: a cohort study

The Impact of Diet and Nutrition on Prostate Cancer - Food for Thought?

PURPOSE OF REVIEW

Prostate cancer is the second most common type of cancer in men. Its incidence varies widely and is influenced by geographic location, race, ethnicity, lifestyle factors, and diet. The purpose of this review is to discuss the association between prostate cancer and diet and outline the impact of fats, carbohydrates, proteins, vitamins and phytonutrients on the pathogenesis of disease.

RECENT FINDINGS

Although conclusive evidence is limited, current data is indicative that a diet low in particular fats, animal proteins, dairy products and high in vegetables and fruits can be beneficial in supporting the course of disease. Promoting a dietary pattern low in processed meat, dairy products, refined carbohydrates and saturated fats, but high in fruits and vegetables may have beneficial effects on prostate metabolism and inhibit various stages of carcinogenesis.

Blood biomarkers of trans-fatty acid intake among Nigerian adults in the Federal Capital Territory: a cross-sectional study

BACKGROUND

Intake of trans-fatty acids (TFAs) is an established risk factor for cardiovascular disease. In April 2023, Nigeria passed regulations limiting TFA content in foods, fats, and oils, but the current level of TFA exposure in the Nigerian population is unknown.

OBJECTIVES

To quantify trans-fatty acid (TFA) biomarkers in dried blood spots from Nigerian adults in the Federal Capital Territory before policy enforcement, establish baseline levels for future evaluations, assess subgroup variations by demographic and socioeconomic factors, and compare TFA levels with data from 30 countries worldwide.

METHODS

We used gas chromatography to measure TFA content in dried blood spots from adults participating in a cross-sectional household survey using a representative sampling frame. Individual TFA (t-16:1, t-18:1, and t- 18:2) and their total were expressed as percentage of total fatty acids. We assessed differences in TFA levels between subgroups based on sex, age, body mass index (BMI), education, income, and local government area using multivariable-adjusted linear regression models. Mean TFA levels were compared with samples from individuals in 30 countries.

RESULTS

In 213 adults (62% females; mean age: 36 y, mean BMI: 25.9 kg/m2), the mean TFA level in dried blood spots was 0.61% of total fatty acids (range: 0.23%-1.31%). In multivariable-adjusted models, TFA levels were higher in younger adults {<30 y compared with ≥42 y, 0.07% [95% confidence interval (CI): 0.00, 0.15], P = 0.047}, those without a high school degree [compared with higher education, 0.08% (95% CI: 0.01, 0.16), P = 0.023], and residents of Abuja Municipal Area Council [compared with residents in Gwagwalada, 0.12% (95% CI: 0.05, 0.20), P = 0.001]. Total TFA levels were comparable with international samples, but t-16:1 and t-18:1 appeared lower, whereas t-18:2 appeared greater (52% of all TFA), in the Nigerian samples.

CONCLUSIONS

These results provide a baseline assessment of TFA exposure in Nigerian adults to evaluate implementation and effect of national regulation passed in 2023. The observed subgroup differences may help identify subpopulations for targeted interventions to reduce TFA intake.

Therapeutic potential of palmitoleic acid in non-alcoholic fatty liver disease: Targeting ferroptosis and lipid metabolism disorders

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a metabolic syndrome associated with obesity and type 2 diabetes mellitus. Currently, there are no effective drugs to treat NAFLD. Palmitoleic acid (PA) has demonstrated therapeutic potential in managing various metabolic diseases and inflammation. Although ferroptosis is known to play a critical role in the NAFLD development, it remains unclear whether PA can alleviate NAFLD by inhibiting ferroptosis.

METHODS

Thirty C57BL/6 mice were divided into three groups: standard diet, high-fat diet (HFD), and HFD with PA. The experiment lasted 16 weeks.

RESULTS

PA alleviated liver injury, hepatitis, and dyslipidemia in HFD-induced NAFLD mice. It improved insulin resistance, downregulated genes and proteins related to fat synthesis, and upregulated genes and proteins linked to lipolysis and fat oxidation. Mechanistically, bioinformatics enrichment revealed the involvement of ferroptosis in NAFLD. PA mitigated oxidative stress and reduced liver iron content in NAFLD. It downregulated acyl-CoA synthetase long-chain family member 4 (ACSL4) expression while upregulating glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11) expression, thereby inhibiting ferroptosis.

CONCLUSION

PA exerts a protective effect against liver lipotoxicity by inhibiting lipid metabolism-mediated ferroptosis. These findings provide new insights into preventive and therapeutic strategies for the pathological processes of NAFLD.

Ruminant Trans Fatty Acid Intake Modulates Inflammation Pathways in the Adipose Tissue Transcriptome of C57BL/6 Mice

SCOPE

The study aims to analyze transcriptomic profiles in adipose tissues postconsumption of elaidic acid (EA; trans-18:1n-9) and trans-palmitoleic acid (TPA; trans-16:1n-7), elucidating their different effects on inflammation and glucose metabolism.

METHODS AND RESULTS

Twenty C57BL/6 mice are divided into four groups. Each group receives one of the following formulations in drinking water: lecithin nanovesicles, nanovesicles containing either lecithin with EA or TPA (86:14 w/w), or water (control) for 28 days with a regular fat diet (18% calories from fat). Total RNA is extracted, and paired-end sequencing is performed. TPA intake alters the expression of 351 genes compared to EA intake, including 11 downregulated and 340 upregulated genes (fold change [FC] >1.5, p < 0.05). TPA compares to EA upregulated: Slc5a8, Lcn2, Csf3, Scube1, Mapk13, Bdkrb2, Ctla2a, Slc2a1, Oas3, Cx3cl1, Oas2, Nlrp6, Pycard, Cyba, Ddr1, and Prkab1 and downregulated Fas gene. These genes are related to the NOD-like receptor, lipid and atherosclerosis, IL-17 signaling, TNF, nonalcoholic fatty liver disease, cytokine-cytokine receptor interaction, adipocytokine, glucagon, insulin resistance, and inflammatory mediator regulation of TRP channels signaling.

CONCLUSION

TPA intake has a distinct impact on the regulation of inflammation and diabetes-related pathways in adipose tissue compared to EA.

Effect of daily avocado consumption for 6 mo compared with habitual diet on red blood cell fatty acid profiles and association with cardiometabolic risk factors in individuals with abdominal obesity: a randomized trial

BACKGROUND

Avocado intake improves dietary fat quality, but the subsequent impact on red blood cell (RBC) saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA), and trans-fatty acid (TFA) composition and association with cardiometabolic health, has not been elucidated.

OBJECTIVES

To compare the effect of consuming 1 avocado/d relative to habitual diet (HAB) on RBC-FA profiles, and their association with visceral adiposity and cardiometabolic risk factors (CMRFs) in individuals with abdominal obesity.

METHODS

RBC-FA profiling at baseline, 3- and 6 mo was conducted in participants (n = 994) from the Habitual Diet and Avocado Trial (HAT). HAT was a multisite, free-living, parallel-arm intervention study in which participants were randomly assigned to either the avocado-supplemented group (AVO, usual diet with 1 avocado/d) or the HAB group (usual diet with limited avocado intake) for 6 mo. Changes in RBC-FA profiles, a secondary outcome measure, were determined within and between groups using linear regression and mixed effect models, adjusting for age, sex, BMI, clinical site, smoking status, and percentage of energy intake from fat at baseline. The association between changes in RBC-FAs with visceral adiposity measures and CMRFs was assessed after covariate and False Discovery Rate (FDR <0.05) adjustment.

RESULTS

No major differences in RBC-FA profiles were observed between groups, with the exception of MUFA cis-vaccenic [18:1n-7c], which was significantly higher in AVO (β: 0.11 [0.05, 0.17]) compared with the HAB (β: 0.03 [-0.03, 0.08]) participants. In the HAB but not AVO group, increases in MUFA cis (18:1n-7c, oleic [18;1n-9c], erucic [22:1n-9c]) and MUFA trans (palmitelaidic [16:1n-7t], vaccenic [18:1n-7t], elaidic [18:1n-9t], and petroselaidic [18;1n-10-12t), as well as PUFA γ-linolenic [18:3n-6], dihomo-γ-linolenic [20:3n-6], arachidonic [20:4n-6], and α-linolenic [18:3n-3] were associated with unfavorable changes in visceral adiposity measures, lipid profiles, glucose, insulin and high sensitivity C-reactive protein concentrations.

CONCLUSIONS

Daily avocado intake over 6-mo modified RBC-MUFA composition, notably 18:1n-7c, and potentially mitigated some of the unfavorable individual RBC-FA-CMRF associations observed over time in the HAB group. This trial was registered at https://clinicaltrials.gov/study as NCT03528031.

Investigating the Dietary Impact on Trans-Vaccenic Acid (Trans-C18:1 n-7) and Other Beneficial Fatty Acids in Breast Milk and Infant Formulas

Maternal diet plays a significant role in the fatty acid composition of breast milk. Dietary products such as milk and meat are the primary sources of natural TFAs for humans. These peculiar fatty acids hold nutritional significance as they not only lack the detrimental effects of industrially produced trans fats on the endothelium characteristic, but they also exhibit anti-inflammatory properties. The relationship between the presence of eight fatty acids in breast milk (including natural TFAs trans-vaccenic and conjugated linoleic acid) and the maternal diet has been explored, and their abundance has been compared to that of infant formulas. Two cohorts of lactating women, originating from a Spanish region, participated in this study; they adhered to the Southern European Atlantic diet or the Atlantic diet. While the consumption of conventional meat or dairy products does not seem to increase the abundance of TFAs in breast milk, trans-vaccenic and oleic acid are among the most distinctive features of breast milk fat in mothers consuming naturally improved dairy products with an improved fatty acid profile. The most significant differences between natural breastfeeding and formula feeding lie in natural TFAs, since formulas are notably deficient in natural TFAs while being overfortified in alpha-linolenic acid in comparison to breast milk. We suggest an improvement in the formulation of these products through using cow's milk with an optimal fatty acid profile that better mimics the fatty acid composition found in human milk.

Increased lipogenesis and lipidosis of gallbladder epithelium in dogs with gallbladder mucocele formation

BACKGROUND

Gallbladder disease in people is frequently associated with disorders of lipid metabolism and metabolic syndrome. A recently emergent gallbladder disease of dogs, referred to as mucocele formation, is characterized by secretion of abnormal mucus by the gallbladder epithelium and is similarly associated with hyperlipidemia, endocrinopathy, and metabolic dysfunction. The cause of gallbladder mucocele formation in dogs is unknown.

METHODS

A prospective case-controlled study was conducted to gain insight into disease pathogenesis by characterization of plasma lipid abnormalities in 18 dogs with gallbladder mucocele formation and 18 age and breed matched control dogs using direct infusion mass spectrometry for complex plasma lipid analysis. This analysis was complemented by histochemical and ultrastructural examination of gallbladder mucosa from dogs with gallbladder mucocele formation and control dogs for evidence of altered lipid homeostasis of the gallbladder epithelium.

RESULTS

Gallbladder mucocele formation in dogs carried a unique lipidomic signature of increased lipogenesis impacting 50% of lipid classes, 36% of esterified fatty acid species, and 11% of complex lipid species. Broad enrichment of complex lipids with palmitoleic acid (16:1) and decreased abundance within complex lipids of presumptive omega-3 fatty acids eicosapentaenoic (20:5) and docosahexaenoic (22:6) was significant. Severe lipidosis of gallbladder epithelium pinpoints the gallbladder as involved causally or consequently in abnormal lipid metabolism.

CONCLUSION

Our study supports a primary increase in lipogenesis in dogs with mucocele formation and abnormal gallbladder lipid metabolism in disease pathogenesis.

Palmitoleic Acid Ameliorates Metabolic Disorders and Inflammation by Modulating Gut Microbiota and Serum Metabolites

SCOPE

Palmitoleic acid (POA) is an omega-7 monounsaturated fatty acid that has been suggested to improve metabolic disorders. However, it remains unclear whether gut microbiota plays a role in the amelioration of metabolic disorders by POA. This study aims to investigate the regulation of POA on metabolism, as well as systemic inflammation in HFD-fed mice from the perspective of serum metabolome and gut microbiome.

METHODS AND RESULTS

Thirty-six C57BL/6 male mice are randomly assigned to either a normal chow diet containing 1.9% w/w lard or an HFD containing 20.68% w/w lard or 20.68% w/w sea buckthorn pulp oil for 16 weeks. The study finds that POA significantly attenuated hyperlipidemia, insulin resistance, and inflammation in HFD-fed mice. POA supplementation significantly alters the composition of serum metabolites, particularly lipid metabolites in the glycerophospholipid metabolism pathway. POA obviously increases the abundance of Bifidobacterium and decreases the abundance of Allobaculum. Importantly, the study finds that glycerophosphocholine mediates the effect of Bifidobacterium on LDL-C, sphingomyelin mediates the effect of Bifidobacterium on IL-6, and maslinic acid mediates the effect of Allobaculum on IL-6.

CONCLUSION

The results suggest that exogenous POA can improve metabolic disorders and inflammation in HFD-fed mice, potentially by modulating the serum metabolome and gut microbiome.

Metabolic effects of milk fatty acids: A literature review

Milk and dairy products are known to have a significant role in human development and tissue maintenance due to their high nutritional value. With the higher incidence of obesity and metabolic diseases, nutrition and public health authorities have recommended the intake of fat-free or low-fat dairy due to the saturated fatty acid content of whole-fat products and their effect on serum cholesterol levels. However, recent studies have questioned the association between milk fat consumption and cardiometabolic risk. This literature review aims to compile the scientific evidence of the metabolic effects of milk fatty acids in clinical and basic research studies, as well as their relationship with metabolic disorders and gut microbiota composition. Research shows that various milk fatty acids exert effects on metabolic alterations (obesity, type 2 diabetes and cardiovascular diseases) by modifying glucose homeostasis, inflammation and lipid profile-related factors. Additionally, recent studies have associated the consumption of milk fatty acids with the production of metabolites and the promotion of healthy gut microbiota. From mainly observational studies, evidence suggests that milk and dairy fatty acids are not directly linked to cardiometabolic risk, but further controlled research is necessary to clarify such findings and to assess whether dietary recommendations to choose low-fat dairy foods are necessary for the population for the prevention of obesity and cardiometabolic disease.

Screening for the production of polyunsaturated fatty acids and cerebrosides in fungi

AIMS

To investigate fatty acid, including polyunsaturated fatty acids (PUFA), and cerebroside production of a large diversity of fungi from the Ascomycota, Basidiomycota, and Mucoromycota phyla.

METHODS AND RESULTS

Seventy-nine fungal strains were grown in Kavadia medium using a microcultivation system, i.e. Duetz microtiter plates. Following cultivation, fatty acid and cerebroside contents were analyzed by gas chromatography-flame ionization detection (GC-FID) and high performance thin-layer chromatography (HPTLC), respectively. Mucoromycota fungi appeared as the most promising candidates for omega-6 PUFA production. The best omega-6 producer, including γ-linolenic acid (GLA, 18:3n-6), was Mucor fragilis UBOCC-A109196 with a concentration of 647 mg L-1 total omega-6 PUFA (representing 35% of total fatty acids) and 225 mg L-1 GLA (representing 12% of total fatty acids). Arachidonic acid concentration (20:4n-6) was the highest in Mortierella alpina UBOCC-A-112046, reaching 255 mg L-1 and 18.56% of total fatty acids. Interestingly, several fungal strains were shown to produce omega-7 monounsaturated fatty acids. Indeed, Torulaspora delbrueckii strains accumulated palmitoleic acid (16:1n-7) up to 20% of total fatty acids, reaching 114 mg L-1 in T. delbrueckii UBOCC-A-214128, while C. elegans UBOCC-A-102008 produced mainly paullinic acid (20:1n-7) with concentrations up to 100 mg L-1. Concerning cerebroside production, HPTLC appeared as a relevant approach for their detection and quantification. Promising candidates belonging to the Mucoromycota phylum were found, especially in the Absidia genus with A. spinosa UBOCC-A-101332 as the best producer (12.7 mg L-1).

CONCLUSIONS

The present study highlighted PUFA and cerebroside production in a large diversity of fungi and the fact that members of the Mucoromycota phylum are good producers of PUFA as well as cerebrosides.

Evaluation of the Hypoglycemic and Hypolipidemic Potential of Extract Fraction of Quercus baloot Griff Seeds in Alloxan-induced Diabetic Mice

INTRODUCTION

The discovery and development of new phytomedicines can be greatly aided by plants because of their tremendous therapeutic benefits, efficiency, cost-effectiveness, lack of side effects, and cheaper therapies. In this regard, Quercus baloot, generally known as oak, is used in folkloric medicine for treating and preventing various human disorders, including diabetes.

AIM

For this purpose, the present study aimed to evaluate crude methanolic extract and various fractions of Quercus baloot for antihyperlipidemic and antihyperglycemic potential followed by the analysis of active compounds.

METHODS

The hypoglycemic and hypolipidemic activity was evaluated in Swiss male Albino mice by administering an oral dose of 150-300 mg/kg of Q. baloot extracts in alloxan induced diabetic mice for 14 days.

RESULTS

The results revealed that crude methanolic extract at a dose of 300 mg/kg exhibited a significant reduction in the blood glucose level (198.50 ± 1.99 mg/dl) at day 14 and the same treatment significantly increased the body weight (31.26 ± 0.27 g) at day 14 in comparison to the control group. Moreover, the biochemical parameters were investigated which presented an increase in high-density lipids (HDL) (30.33 ± 0.33 mg/dl), whereas low-density lipids (LDL) showed a significant decrease (105.66 ± 0.26 mg/dl). Additionally, triglyceride levels 104.83 ± 0.70 mg/dl, and total cholesterol 185.50 ± 0.76 mg/dl are significantly decreased. In serum biochemical analysis creatinine and hepatic enzyme markers, like serum glutamate pyruvate transaminase (32.00 ± 0.36 U/mg), serum glutamate oxaloacetate transaminase (34.33 ± 0.61 U/mg), and alkaline phosphatase (157.00 ± 0.73 U/mg), were significantly reduced by the crude methanolic extract at a dose of 300 mg/kg as compared to the control group. The antioxidant enzymes like Superoxide dismutase (4.57 ± 0.011), peroxidases dismutase (6.53 ± 0.014, and catalase (8.38 ± 0.014) at a dosage of 300 mg/kg of methanolic extract exhibited a significant increase. The histopathological study of the diabetic heart, liver, and pancreas showed substantial restoration of damaged tissues in the methanolic extract 150 and 300 mg/kg treated group, which supports the effectiveness of Q. baloot seeds. The gas chromatography-mass spectrometry analysis of methanolic extract identified 10 antidiabetic active compounds in the Q. baloot seeds, validating the antihyperglycemic activity. Thus, methanolic crude extract at the doses 150 and 300 mg/kg of Q. baloot showed significant antihyperlipidemic and antihyperglycemic activities, which validate the folkloric utilization of Q. baloot as a remedy in diabetes.

CONCLUSION

In conclusion, the 300 mg/kg methanolic extract of Q. baloot has notable hypoglycemic and hypolipidemic potential, supporting the plant's traditional medicinal usage in the treatment of diabetes and its complications. Further studies are needed for the purification, characterization, and structural clarification of bioactive compounds.

Maternal n-7 Unsaturated Fatty Acids Protect the Fetal Brain from Neuronal Degeneration in an Intrauterine Hyperglycemic Animal Model

We previously reported that glycation induces insulin resistance in the hearts of newborn pups from a gestational diabetes mellitus (GDM) rat model. Administration of n-3 unsaturated fatty acids suppressed glycation and improved signaling in GDM rat pups. In this study, we investigated their effects on cranial neurons using the GDM rat model and PC12 cells derived from rat adrenal pheochromocytomas. Additionally, we examined whether n-3 and n-7 unsaturated fatty acids (cis-palmitoleic acid [CPA] and trans-palmitoleic acid [TPA]) ameliorate the detrimental effects of high glucose exposure on rats. In the neonatal cerebrum of GDM rats, increased levels of advanced glycation end products (AGEs) inhibited Akt phosphorylation; however, CPA and TPA intake during pregnancy ameliorated these abnormalities. Furthermore, exposure to high-glucose-induced apoptosis in PC12 cells compared to the cells cultured in control glucose. PC12 cells exposed to high-glucose with fatty acids exhibited reduced AGE production and apoptosis induction compared to the high-glucose group. These findings suggest that a hyperglycemic environment during pregnancy promotes AGE formation in brain neuronal proteins and induces apoptosis. Both TPA and CPA mitigated these abnormalities; however, CPA is cytotoxic, highlighting its safety in pregnant women.

Trans-palmitoleic acid, a dairy fat biomarker, stimulates insulin secretion and activates G protein-coupled receptors with a different mechanism from the cis isomer

Dietary trans-palmitoleic acid (trans 16:1n-7, tPOA), a biomarker for high-fat dairy product intake, has been associated with a lower risk of type 2 diabetes mellitus (T2DM) in some cross-sectional and prospective epidemiological studies. Here, we investigated the insulin secretion-promoting activity of tPOA and compared them with the effects evoked by the cis-POA isomer (cPOA), an endogenous lipokine biosynthesized in the liver and adipose tissue, and found in some natural food sources. The debate about the positive and negative relationships of those two POA isomers with metabolic risk factors and the underlying mechanisms is still going on. Therefore, we examined the potency of both POA isomers to potentiate insulin secretion in murine and human pancreatic β cell lines. We also investigated whether POA isomers activate G protein-coupled receptors proposed as potential targets for T2DM treatment. We show that tPOA and cPOA augment glucose-stimulated insulin secretion (GSIS) to a similar extent; however, their insulin secretagogue activity is associated with different signaling pathways. We also performed ligand docking and molecular dynamics simulations to predict the preferred orientation of POA isomers and the strength of association between those two fatty acids and GPR40, GPR55, GPR119, and GPR120 receptors. Overall, this study provides insight into the bioactivity of tPOA and cPOA toward selected GPCR functions, indicating them as targets responsible for the insulin secretagogue action of POA isomers. It reveals that both tPOA and cPOA may promote insulin secretion and subsequently regulate glucose homeostasis.

Ostrich oil as a fat substitute in milk-based infant formula

In this study, the possibility of replacing vegetable fats with ostrich oil in infant formula (IF) production was investigated. The fatty acid profile, the positional distribution of fatty acids in the triacylglycerols, the cholesterol content, and the physicochemical properties of ostrich oil were determined and compared with breast milk fat and vegetable oils. In the next step, two infant formulas were produced using ostrich oil and vegetable oils and the physicochemical properties, rheological properties, color parameters, and sensory analysis of the resultant powders were compared. The results showed that the predominant fatty acids in ostrich oil are palmitic acid, oleic acid, and linoleic acid which is similar to breast milk fat and vegetable oils. The presence of appropriate cholesterol content in ostrich oil makes it more similar to breast milk fat compared to vegetable fats. Palmitic acid was located at sn-2 position in 15% triacylglycerol from ostrich fat, which was equal to the amount reported for vegetable fats. The incorporation of ostrich oil in infant formula production showed that there is no statistically significant difference between quality attributes of powder formulated with ostrich oil or vegetable oils. Therefore, ostrich oil can be introduced as a new source of edible oil, and addition of ostrich oil is an effective way to reduce the gap between the composition of breast milk and infant formula.

Industrial and Ruminant Trans-Fatty Acids-Enriched Diets Differentially Modulate the Microbiome and Fecal Metabolites in C57BL/6 Mice

Industrially originated trans-fatty acids (I-tFAs), such as elaidic acid (EA), and ruminant trans-fatty acids (R-tFAs), such as trans-palmitoleic acid (TPA), may have opposite effects on metabolic health. The objective was to compare the effects of consuming 2–3% I-tFA or R-tFA on the gut microbiome and fecal metabolite profile in mice after 7 and 28 days. Forty C57BL/6 mice were assigned to one of the four prepared formulations: lecithin nanovesicles, lecithin nanovesicles with EA or TPA, or water. Fecal samples and animals’ weights were collected on days 0, 7, and 28. Fecal samples were used to determine gut microbiome profiles by 16S rRNA sequencing and metabolite concentrations by GC/MS. At 28 days, TPA intake decreased the abundance of Staphylococcus sp55 but increased Staphylococcus sp119. EA intake also increased the abundance of Staphylococcus sp119 but decreased Ruminococcaceae UCG-014, Lachnospiraceae, and Clostridium sensu stricto 1 at 28 days. Fecal short-chain fatty acids were increased after TPA while decreased after EA after 7 and 28 days. This study shows that TPA and EA modify the abundance of specific microbial taxa and fecal metabolite profiles in distinct ways.

High-Fat Dairy Products May Decrease the Risk of Chronic Kidney Disease Incidence: A Long-Term Prospective Cohort Study

OBJECTIVE

The association between consumption of dairy products and risk of chronic kidney disease (CKD) is under debate. We aimed to determine the potential effects of total and subtypes of dairy intake on the occurrence of CKD.

METHODS

This study was conducted within the Tehran Lipid and Glucose Study (TLGS) on 2416 CKD-free adults. At baseline, consumption of dairy products was estimated using a validated 168-items semiquantitative food frequency questionnaire. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of CKD were calculated in tertile categories of dairy products. Also, the CKD risk was estimated with multivariable Cox regression to substitute total dairy with other dietary protein sources.

RESULTS

During 8.4 years of follow-up, the incidence rate of CKD was 21%. The participants' mean (±SD) age was 38 (±13) years and 46% were men. Dietary intakes of total dairy, low-fat dairy, and fermented dairy were not associated with CKD risk. There were significant lower risks of CKD in the highest compared to the lowest tertiles of high-fat dairy (HR = 0.76, 95% CI = 0.60-0.95) and high-fat milk (HR = 0.75, 95% CI = 0.59-0.96). However, no significant associations were found between other categories of dairy products and CKD incidence. Substitutions of total dairy with other dietary protein sources were not associated with CKD risk.

CONCLUSIONS

In this study, higher intakes of high-fat dairy and high-fat milk were associated with lower risks of CKD. No significant associations were found between other dairy products and CKD. More prospective and clinical trials are needed to clarify the issue.

C57bl/6 Mice Show Equivalent Taste Preferences toward Ruminant and Industrial Trans Fatty Acids

Two distinct types of trans fatty acids (TFA) are found in the diet. Industrial TFA such as elaidic acid (EA) have deleterious effects on metabolic risk factors, and oppositely ruminant TFA including trans-palmitoleic acid (TPA) may have beneficial effects. The objective is to evaluate the taste preference between EA, TPA, lecithin or water. In this study, 24 female C57BL/6 mice were microchipped and placed in two separate IntelliCages^®. Nano encapsulated TFA or lecithin were added to drinking water in different corners of the cage with normal diet. The study was carried out over 5 weeks, during which mice were exposed to water only (weeks 1 and 3), TFA or lecithin (week 2), and EA or TPA (weeks 4 and 5). Mice weights, corner visits, nose pokes (NP), and lick number were measured each week. The results demonstrated that mice consume more TFA, either EA or TPA, compared with lecithin. In addition, the mice licked more EA compared with TPA in one cage; conversely, in the other cage they licked more TPA compared with EA. However, when TFA positions were swapped, mice had equal licks for EA and TPA. In sum, mice preferred TFA, in equal matter compared with controls; therefore, the results demonstrate the potential for TFA-type substitution in diet.

Dairy Food Consumption Is Associated with Reduced Risk of Heart Disease Mortality, but Not All-Cause and Cancer Mortality in US Adults

Previous evidence has linked animal protein intake, including dairy foods, with an increased risk in mortality from all-causes and certain chronic diseases, including cancer and heart disease. The objective of the current analysis was to examine associations between total dairy consumption with mortality from all-causes, cancer, and heart disease. Data for adults (≥19 y; n = 54,830) from the Third National Health and Nutrition Examination Survey (NHANES) and NHANES 1999-2014 were linked with mortality data through 2015. Individual usual intake for dairy foods were estimated using the National Cancer Institute method. Hazard ratio (HR) models were fit for mortality types (all cause, cancer, heart disease) and measures of usual intakes of dairy. Multivariable analysis further adjusted for age, gender, ethnicity, waist circumference, smoking status, education level, chronic condition status (i.e., based on cancer, myocardial infarct, and diabetes/diabetes medication reported), weight loss attempts, and % kcal from animal protein. No associations were seen between dairy food intake and mortality risk from all-causes [HR = 0.97; confidence intervals (CI): 0.85-1.11; p = 0.67], and cancer [HR = 0.95; CI: 0.75-1.20; p = 0.65] when comparing the lowest quartile to the highest quartile of consumption. Dairy food consumption was associated with a 26% reduced risk for heart disease mortality when comparing the lowest quartile to the highest quartile [HR = 0.74; CI: 0.54-1.01; p = 0.05]. Further analyses in different age groups showed that dairy food consumption was associated with 39% and 31% reduced risk for heart disease mortality in older adults 51-70 and ≥51 y, respectively [adults 51-70 y: HR = 0.61; CI: 0.41-0.91; p = 0.01; adults ≥51 y: HR = 0.69; CI: 0.54-0.89; p = 0.004]. These results contradict previous findings that have linked dairy foods to increased mortality risk. Further, dairy foods as part of a healthy dietary pattern, may help lower heart disease mortality risk.

Associations between dairy fat intake, milk-derived free fatty acids, and cardiometabolic risk in Dutch adults

PURPOSE

Milk-derived free fatty acids (FFAs) may act as both biomarkers of intake and metabolic effect. In this study we explored associations between different types of dairy consumption, a selection of milk-derived free fatty acids, and cardiometabolic disease (CMD) risk factors.

METHODS

Sixty-seven FFAs were quantified in the plasma of 131 free-living Dutch adults (median 60 years) using gas chromatography-flame ionization detector. Intakes of different dairy foods and groups were assessed using a food frequency questionnaire. Twelve different CMD risk factors were analyzed. Multiple linear regressions were used to evaluate the associations under study.

RESULTS

Based on the fully adjusted models, 5 long-chain unsaturated FFAs (C18:1 t13 + c6 + c7 + u, C18:2 c9t11 + u, C20:1 c11, C20:3 c8c11c14, and C20:4 c5c8c11c14), 2 medium-chain saturated FFAs (C15, C15 iso), and a trans FFA (C16:1 t9) were positively associated with at least one variable of dairy intake, as well as plasma total and LDL cholesterol, blood pressure, and SCORE (p ≤ 0.05). A long-chain PUFA associated with high-fat fermented dairy intake (C18:2 t9t12), was negatively associated with serum triglyceride levels, and a long-chain saturated FFA associated with cheese intake (C18:1 u1) was negatively associated with plasma LDL cholesterol and serum triglyceride levels. No clear associations were observed between dairy intake and CMD risk factors.

CONCLUSION

Milk-derived FFAs could act as sensitive biomarkers for dairy intake and metabolism, allowing the association between dairy and CMD risk to be more precisely evaluated.

New research development on trans fatty acids in food: Biological effects, analytical methods, formation mechanism, and mitigating measures

The trans fatty acids (TFAs) in food are mainly generated from the ruminant animals (meat and milk) and processed oil or oil products. Excessive intake of TFAs (>1% of total energy intake) caused more than 500,000 deaths from coronary heart disease and increased heart disease risk by 21% and mortality by 28% around the world annually, which will be eliminated in industrially-produced trans fat from the global food supply by 2023. Herein, we aim to provide a comprehensive overview of the biological effects, analytical methods, formation and mitigation measures of TFAs in food. Especially, the research progress on the rapid, easy-to-use, and newly validated analytical methods, new formation mechanism, kinetics, possible mitigation mechanism, and new or improved mitigation measures are highlighted. We also offer perspectives on the challenges, opportunities, and new directions for future development, which will contribute to the advances in TFAs research.

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.

Saturated fats, dairy foods and cardiovascular health: No longer a curious paradox?

Cardiovascular diseases (CVDs) are a major cause of death and morbidity in many parts of the world, and many dietary guidelines limit the intake of saturated fatty acids (SFA) as they are regarded as an important risk factor for CVDs due to their association with increased blood cholesterol. Dairy foods are often a major contributor to dietary intake of SFA, and since many dietary guidelines contain restrictions on SFA intake, this can lead to a moderation of dairy food intake despite meta-analyses generally showing dairy to have a neutral or negative association with CVDs. Many prospective studies and randomised controlled trials do not support a simple positive association between SFA intake and the risk of atherosclerotic CVD and its components although some early studies had a number of methodological weakness. Studies that included blood cholesterol data do broadly support the positive relationship between SFA and blood low-density lipoprotein cholesterol (LDL-C) but without increased CVD risk resulting, despite LDL being a causal factor in atherosclerotic CVD. These data suggest that LDL-C alone is not a consistently good predictor or cause of CVD risk, perhaps particularly in relation to dairy food consumption although some non-dairy food studies have also shown LDL-C reduction was not reflected in reduced CVD risk. This narrative review examines some reasons for these findings. Overall, restrictions on dairy food intake do not seem warranted, although there remains a need to further understand the association of different dairy food types with chronic diseases, perhaps particularly for type 2 diabetes.

Simultaneous determination of cis- and trans-palmitoleic acid in rat serum by UPLC-MS/MS

Palmitoleic acid, a monounsaturated fatty acid which could affect glucose and lipid metabolism and reduce insulin resistance has two isomers, i.e. cis-palmitoleic acid (cPOA) and trans-palmitoleic acid (tPOA). However, the pharmacokinetic, metabolic transformation and structure–activity relationship of the two isomers have not been reported. A precise and accurate ultra performance liquid chromatography–tandem mass spectroscopy (UPLC–MS/MS) method was developed to determine cPOA and tPOA simultaneously. Both the cPOA and tPOA were administered i.g. (intragastric gavage) to rats at 75 mg/kg. Serum samples were collected and analyzed for the two isomers by UPLC–MS/MS on a reverse-phase BDS C18 column equilibrated and eluted with water (A) and acetonitrile (B) at a flow rate of 0.3 mL/min. The calibration curves for cPOA and tPOA were linear over the range 0.1–12 μg/mL. Analytes were monitored by selected-reaction monitoring in negative electrospray ionization mode. The Tmax of cPOA was 0.94 ± 0.44 h and the Cmax 8.17 ± 1.97 μg/L, and the Tmax and Cmax of tPOA were 1.50 ± 0.98 h and 14.77 ± 11.91 μg/L, respectively. AUC_0–24 h of cPOA and tPOA were 59.45 ± 29.83 and 113.88 ± 72.25 mg/L·h. The method was applied in pharmacokinetic study of cPOA and tPOA in rat serum successfully. Besides, the concentrations of cPOA and tPOA in rat serums were observed fluctuating with a consistent trend, which may be due to reciprocal bio-convert in the body.

Saturated fatty acid biomarkers and risk of cardiometabolic diseases: A meta-analysis of prospective studies

Background and aims

Evidence regarding associations of circulating saturated fatty acids (SFAs) with chronic diseases is mixed. The objective of this study was to determine the associations between total or individual SFA biomarkers and the risk of cardiometabolic diseases.

Methods

Four electronic databases were searched from inception to March 2022. Three investigators independently assessed for inclusion and extracted data. Random-effects or fixed-effects models was used to estimate the pooled relative risks (RRs) and corresponding 95% confidence intervals (CIs) for the association of total or individual SFA biomarkers, including even-chain SFAs (e.g., 14:0, myristic acid; 16:0, palmitic acid; 18:0, stearic acid), odd-chain SFAs (e.g., 15:0, pentadecanoic acid; 17:0, margaric acid) and very-long-chain SFAs (VLCSFAs; e.g., 20:0, arachidic acid; 22:0, behenic acid; 24:0, lignoceric acid), with risk of incident type 2 diabetes (T2D), cardiovascular disease [CVD; coronary heart disease (CHD) inclusive of stroke], CHD and stroke.

Results

A total of 49 prospective studies reported in 45 articles were included. Higher concentration of circulating total SFAs was associated with an increasing risk of cardiometabolic diseases, the risk increased significantly by 50% for CVD (95%CI:1.31-1.71), 63% for CHD (95%CI:1.38-1.94), 38% for stroke (95%CI:1.05-1.82), respectively. Similarly, levels of even-chain SFAs were positively associated with higher risk of chronic diseases, with RRs ranging from 1.15 to 1.43. In contrast, the risk of cardiometabolic diseases was reduced with increasing odd-chain SFA levels, with RRs ranging from 0.62 to 0.91. A higher level of VLCSFAs corresponded to 19% reduction in CVD. Further dose-response analysis indicated that each 50% increment in percentage of total SFAs in circulating was associated with an 8% higher risk of T2D (RR: 1.08, 95%CI: 1.02-1.14) and trends toward higher risk of CVD (RR: 1.15, 95%CI: 0.98-1.34). Inverse linear relationships were observed between 17:0 biomarker and T2D or CVD risk.

Conclusion

Our findings support the current recommendations of reducing intake of saturated fat as part of healthy dietary patterns. Further studies are needed to confirm our findings on these SFAs in relation to cardiometabolic outcomes and to elucidate underlying mechanisms.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022329182], identifier [CRD42022329182].

The mediating role of maternal metabolites between lipids and adverse pregnancy outcomes of gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy, and the demographics of pregnant women have changed in recent decades. GDM is a metabolic disease with short- and long-term adverse effects on both pregnant women and newborns. The metabolic changes and corresponding risk factors should be of great significance in understanding the pathological mechanism of GDM and reducing the incidence of adverse pregnancy outcomes in patients with GDM. The well-known GDM-associated lipids used in clinical tests, such as triglyceride (TG), are thought to play a major role in metabolic changes during GDM, which have a potential causal relationship with abnormal pregnancy outcomes of GDM. Therefore, this study analyzed the relationship between clinical lipid indicators, metabolic profiles, and abnormal pregnancy outcomes in GDM through mediation analysis. By constructing a metabolic atlas of 399 samples from GDM patients in different trimesters, we efficiently detected the key metabolites of adverse pregnancy outcomes and their mediating roles in bridging abnormal lipids and adverse pregnancy outcomes in patients with GDM. Our study confirmed that TG and total cholesterol were independent risk factors for adverse pregnancy outcomes in patients with GDM. Several key metabolites as mediators (e.g., gamma-linolenic acid, heptadecanoic acid, oleic acid, palmitic acid, and palmitoleic acid) have been identified as potential biomarkers for adverse pregnancy outcomes in patients with GDM. These metabolites mainly participate in the biosynthesis of unsaturated fatty acids, which may shed new light on the pathology of GDM and provide insights for further exploration of the molecular mechanisms underlying adverse pregnancy outcomes.

Plasma Industrial and Ruminant Trans Fatty Acids and Incident Type 2 Diabetes in the EPIC-Potsdam Cohort

OBJECTIVE

Although dietary intake of trans fatty acid (TFA) is a major public health concern because of the associated increase in the risk of cardiovascular events, it remains unclear whether TFAs also influence risk of type 2 diabetes (T2D) and whether industrial TFAs (iTFAs) and ruminant TFAs (rTFAs) exert the same effect on health.

RESEARCH DESIGN AND METHODS

To investigate the relationship of 7 rTFAs and iTFAs, including 2 conjugated linoleic acids (CLAs), plasma phospholipid TFAs were measured in a case-cohort study nested within the European Prospective Investigation Into Cancer and Nutrition-Potsdam cohort. The analytical sample was a random subsample (n = 1,248) and incident cases of T2D (n = 801) over a median follow-up of 6.5 years. Using multivariable Cox regression models, we examined associations of TFAs with incident T2D.

RESULTS

The TFA subtypes were intercorrelated with each other, with other fatty acids, and with different food sources. After controlling for other TFAs, the iTFAs (18:1n-6t, 18:1n-9t, 18:2n-6,9t) were not associated with diabetes risk. Some rTFA subtypes were inversely associated with diabetes risk: vaccenic acid (18:1n-7t; hazard ratio [HR] per SD 0.72; 95% CI 0.58-0.89) and t10c12-CLA (HR per SD 0.81; 95% CI 0.70-0.94), whereas c9t11-CLA was positively associated (HR per SD 1.39; 95% CI 1.19-1.62). Trans-palmitoleic acid (16:1n-7t) was not associated with diabetes risk when adjusting for the other TFAs (HR per SD 1.08; 95% CI 0.88-1.31).

CONCLUSIONS

The TFAs' conformation plays an essential role in their relationship to diabetes risk. rTFA subtypes may have opposing relationships to diabetes risk. Previous observations for reduced diabetes risk with higher levels of circulating trans-palmitoleic acid are likely due to confounding.

Dairy as a Source of Iodine and Protein in the UK: Implications for Human Health Across the Life Course, and Future Policy and Research

This narrative review summarizes key concepts in dairy nutrition for supporting human health throughout the life course. Milk and dairy products have been a staple component of our diet for thousands of years and provide a wide range of important nutrients that are otherwise difficult to obtain from dairy-free diets. In this review, we provide a broad perspective on the nutritional roles of iodine and dairy protein in supporting human health during pregnancy and early life, childhood and adolescence, mid- and later-life. New methodologies to identify biomarkers of dairy intake via high-throughput mass spectrometry are discussed, and new concepts such as the role of the food matrix in dairy nutrition are introduced. Finally, future policy and research related to the consumption of dairy and non-dairy alternatives for health are discussed with a view to improving nutritional status across the lifespan.

Chemical profiles with cardioprotective and anti-depressive effects of Morus macroura Miq. leaves and stem branches dichloromethane fractions on isoprenaline induced post-MI depression

This study was conducted to explore the potential cardioprotective and anti-depressive effects of dichloromethane (DCM) fractions of Morus macroura leaves (L) and stem branches (S) on post-myocardial infarction (MI) depression induced by isoprenaline (ISO) in rats in relation to their metabolites. The study was propped with a UPLC-ESI-MS/MS profiling and chromatographic isolation of the secondary metabolites. Column chromatography revealed the isolation of lupeol palmitate (6) that was isolated for the first time from nature with eight known compounds. In addition, more than forty metabolites belonging, mainly to flavonoids, and anthocyanins groups were identified. The rats were injected with ISO (85 mg kg⁻¹, s.c) in the first two days, followed by the administration of M. macroura DCM-L and DCM-S fractions (200 mg kg⁻¹ p.o) for 19 days. Compared with the ISO exposed rats, the treated rats displayed a reduction in cardiac biomarkers (LDH and CKMB), anxiety, and depressive-like behaviour associated with an increase in the brain defense system (SOD and GSH), neuronal cell energy, GABA, serotonin, and dopamine, confirmed by histopathological investigations. In conclusion, DCM-L and DCM-S fractions' cardioprotective and anti-depressive activities are attributed to their metabolite profile. Therefore, they could serve as a potential agent in amending post-MI depression.

This study was conducted to explore the potential cardioprotective and anti-depressive effects of dichloromethane fractions of Morus macroura leaves and stem branches on post-myocardial infarction depression induced by isoprenaline in rats in relation to their metabolites.

Effect of a dietary intervention including minimal and unprocessed foods, high in natural saturated fats, on the lipid profile of children, pooled evidence from randomized controlled trials and a cohort study

Aim

To study the possible effects of a dietary intervention with minimal and unprocessed foods, high in natural saturated fats on the lipid profile and body mass index of children.

Method

This study combines three intervention studies; one non-randomized retrospective cohort study and two randomized controlled trials, to a pooled analysis. The intervention group received a dietary intervention of minimal and unprocessed foods for three to six months, consisting of five times per week green vegetables, three times per week beef, daily 200–300 mL whole cow’s milk (3.4% fat) and whole dairy butter (80% fat) on each slice of bread. The control group continued their usual dietary habits. Raw data of the three intervention studies where combined into one single dataset for data analysis, using mixed effects analysis of covariance to test the effects of the dietary advice on the main study outcomes, which are measurements of the lipid profile.

Results

In total, 267 children aged 1 to 16 years were followed. 135 children were included in the intervention group and 139 children in the control group. Characteristics (age, gender and follow-up period) were equally distributed between the groups at baseline. In the intervention group HDL-cholesterol increased significantly from 1.22 mmol/L, 95% confidence interval (CI) 1.14–1.32 to 1.42 mmol/L 95% CI 1.30–1.65 (p = 0.007). The increase over time in HDL cholesterol in the intervention group was significantly different compared to the increase in the control group (from 1.26 mmol/L, 95% CI 1.19–1.35, to 1.30 mmol/L, 95% CI 1.26–1.37) (p = 0.04). Due to the increased HDL concentration in the intervention group, the total cholesterol/HDL cholesterol ratio decreased significantly from 3.70 mmol/L, 95% CI 3.38–3.87, to 3.25 mmol/L, 95% CI 2.96–3.31 (p = 0.05).

Conclusion

Consumption of minimal and unprocessed foods (high in natural saturated fats) has favourable effects on HDL cholesterol in children. Therefore, this dietary advice can safely be recommended to children.

Total, low-fat, and full-fat dairy consumption and risk of metabolic syndrome among workers

BACKGROUND & AIM

Dairy products may play a beneficial role against metabolic syndrome; however, epidemiological evidence is scarce in Asian populations, who consume less dairy than Western populations. We prospectively investigated the association between dairy product intake, both overall and by fat content, and metabolic syndrome in a Japanese working population.

METHODS

Participants were 1014 workers (aged 19-68 years) without metabolic syndrome at baseline who completed a 3-year follow-up survey. Dietary intake was assessed using a validated self-administered diet history questionnaire. Metabolic syndrome was defined according to the Joint Interim Statement (JIS) criteria. Multiple logistic regression was used to estimate the odds ratio of metabolic syndrome according to tertile of total, low-fat, and full-fat dairy product intake with adjustment for covariates.

RESULTS

At the 3-year follow-up, 66 (6.5%) workers were newly identified as having metabolic syndrome. A trend towards decreased odds of developing metabolic syndrome was observed among those in the highest tertile of total and full-fat dairy product intake: multivariable-adjusted odds ratio for the highest versus lowest tertile was 0.54 (95% CI 0.26-1.12; P for trend = 0.094) for total dairy products and 0.50 (95% CI 0.24-1.05; P for trend = 0.038) for full-fat dairy products. Low-fat dairy intake was not associated with metabolic syndrome.

CONCLUSIONS

Our results suggest that higher intake of full-fat, but not low-fat, dairy products may be associated with a lower risk of metabolic syndrome among Japanese.

Female Fertility and the Nutritional Approach: The Most Essential Aspects

Infertility is an increasing problem that affects couples attempting pregnancy. A growing body of evidence points to a link between diet and female fertility. In fact, data show that a diet high in trans fats, refined carbohydrates, and added sugars can negatively affect fertility. Conversely, a diet based on the Mediterranean dietary patterns, i.e., rich in dietary fiber, omega-3 (ɷ-3) fatty acids, plant-based protein, and vitamins and minerals, has a positive impact on female fertility. An unhealthy diet can disrupt microbiota composition, and it is worth investigating whether the composition of the gut microbiota correlates with the frequency of infertility. There is a lack of evidence to exclude gluten from the diet of every woman trying to become pregnant in the absence of celiac disease. Furthermore, there are no data concerning adverse effects of alcohol on female fertility, and caffeine consumption in the recommended amounts also does not seem to affect fertility. On the other hand, phytoestrogens presumably have a positive influence on female fertility. Nevertheless, there are many unanswered questions with regard to supplementation in order to enhance fertility. It has been established that women of childbearing age should supplement folic acid. Moreover, most people experience vitamin D and iodine deficiency; thus, it is vital to control their blood concentrations and consider supplementation if necessary. Therefore, since diet and lifestyle seem to be significant factors influencing fertility, it is valid to expand knowledge in this area.

Milk Odd and Branched Chain Fatty Acids in Dairy Cows: A Review on Dietary Factors and Its Consequences on Human Health

This review highlights the importance of odd and branched chain fatty acids (OBCFAs) and dietary factors that may affect the content of milk OBCFAs in dairy cows. Historically, OBCFAs in cow milk had little significance due to their low concentrations compared to other milk fatty acids (FAs). The primary source of OBCFAs is ruminal bacteria. In general, FAs and OBCFAs profile in milk is mainly affected by dietary FAs and FAs metabolism in the rumen. Additionally, lipid mobilization in the body and FAs metabolism in mammary glands affect the milk OBCFAs profile. In cows, supplementation with fat rich in linoleic acid and α-linolenic acid decrease milk OBCFAs content, whereas supplementation with marine algae or fish oil increase milk OBCFAs content. Feeding more forage rather than concentrate increases the yield of some OBCFAs in milk. A high grass silage rate in the diet may increase milk total OBCFAs. In contrast to saturated FAs, OBCFAs have beneficial effects on cardiovascular diseases and type II diabetes. Furthermore, OBCFAs may have anti-cancer properties and prevent Alzheimer's disease and metabolic syndrome.

Association between the food security status and dietary patterns with polycystic ovary syndrome (PCOS) in overweight and obese Iranian women: a case-control study

Background

Polycystic ovary syndrome (PCOS), as one of the significant endocrine disorders, is common among women worldwide. Food insecurity (FI) and unhealthy dietary patterns can negatively affect reproductive health. The effects of the lifestyle modifications, especially dietary components, on PCOS are contradictory. The aim was the assessment of association between PCOS with food security status and dietary patterns among overweight or obese women.

Methods

This case-control study was performed on 240 overweight and obese women with and without PCOS (ratio 1:1) referred to the infertility clinic of Arash Hospital, Tehran, Iran. The general and socioeconomic characteristics, anthropometrics (weight, height, body mass index (BMI), waist circumference, hip circumference), physical activity, food security status, and dietary intakes (or patterns) were assessed using valid questionnaires, scales, stadiometer, and tape meter. The significant p-value was < 0.05.

Results

The prevalence of FI was 60% in women with PCOS and 30% in healthy women. PCOS risk was positively related to FI, quasi-western dietary patterns, low economic levels, waist circumference, and menstrual age and negatively with physical activity and healthy dietary patterns, even after controlling the potential confounders (P <  0.05). PCOS women had a higher intake of saturated fats, monounsaturated fats, oleic acid, fluorine, sucrose, and caffeine and a lower intake of vitamins A, B₅, B₆, B₁₂, C, and D, potassium, proteins, carbohydrates, cholesterols, docosahexaenoic acid, potassium, carotenes, lutein, beta-cryptoxanthin, lycopene, calcium, iron, thiamine, riboflavin, niacin, tetra- and dihydrofolate, biotin, phosphorus, magnesium, zinc, copper, fiber (total, insoluble, and crude), glucose, galactose, fructose, and lactose compared to the healthy women (P <  0.05).

Conclusions

FI, quasi-western dietary patterns, low economic levels, and waist circumference were significantly associated with the higher risk of PCOS. The lifestyle changes, especially dietary patterns, may be an essential strategy for reducing PCOS. Further studies are warranted to confirm these findings and to identify the underlying mechanisms.

Exploring the Links between Diet and Inflammation: Dairy Foods as Case Studies

Systemic chronic inflammation may be a contributing factor to many noncommunicable diseases, including diabetes, cardiovascular disease, and obesity. With the rapid rise of these conditions, identifying the causes of and treatment for chronic inflammation is an important research priority, especially with regard to modifiable lifestyle factors such as diet. An emerging body of evidence indicates that consuming certain foods, including dairy foods like milk, cheese, and yogurt, may be linked to a decreased risk for inflammation. To discuss both broader research on diet and inflammation as well as research on links between individual foods and inflammation, the National Dairy Council sponsored a satellite session entitled "Exploring the Links between Diet and Inflammation: Dairy Foods as Case Studies" at the American Society for Nutrition's 2020 LIVE ONLINE Conference. This article, a review based on the topics discussed during that session, explores the links between diet and inflammation, focusing most closely on the relations between intake of dairy fat and dairy foods like milk, cheese, and yogurt, and biomarkers of inflammation from clinical trials. While there is currently insufficient evidence to prove an "anti-inflammatory" effect of dairy foods, the substantial body of clinical research discussed in this review indicates that dairy foods do not increase concentrations of biomarkers of chronic systemic inflammation.

Plasma Lipolysis and Changes in Plasma and Cerebrospinal Fluid Signaling Lipids Reveal Abnormal Lipid Metabolism in Chronic Migraine

Background

Lipids are a primary storage form of energy and the source of inflammatory and pain signaling molecules, yet knowledge of their importance in chronic migraine (CM) pathology is incomplete. We aim to determine if plasma and cerebrospinal fluid (CSF) lipid metabolism are associated with CM pathology.

Methods

We obtained plasma and CSF from healthy controls (CT, n = 10) or CM subjects (n = 15) diagnosed using the International Headache Society criteria. We measured unesterified fatty acid (UFA) and esterified fatty acids (EFAs) using gas chromatography-mass spectrometry. Glycerophospholipids (GP) and sphingolipid (SP) levels were determined using LC-MS/MS, and phospholipase A₂ (PLA₂) activity was determined using fluorescent substrates.

Results

Unesterified fatty acid levels were significantly higher in CM plasma but not in CSF. Unesterified levels of five saturated fatty acids (SAFAs), eight monounsaturated fatty acids (MUFAs), five ω-3 polyunsaturated fatty acids (PUFAs), and five ω-6 PUFAs are higher in CM plasma. Esterified levels of three SAFAs, eight MUFAs, five ω-3 PUFAs, and three ω-6 PUFAs, are higher in CM plasma. The ratios C20:4n-6/homo-γ-C20:3n-6 representative of delta-5-desaturases (D5D) and the elongase ratio are lower in esterified and unesterified CM plasma, respectively. In the CSF, the esterified D5D index is lower in CM. While PLA₂ activity was similar, the plasma UFA to EFA ratio is higher in CM. Of all plasma GP/SPs detected, only ceramide levels are lower (p = 0.0003) in CM (0.26 ± 0.07%) compared to CT (0.48 ± 0.06%). The GP/SP proportion of platelet-activating factor (PAF) is significantly lower in CM CSF.

Conclusions

Plasma and CSF lipid changes are consistent with abnormal lipid metabolism in CM. Since plasma UFAs correspond to diet or adipose tissue levels, higher plasma fatty acids and UFA/EFA ratios suggest enhanced adipose lipolysis in CM. Differences in plasma and CSF desaturases and elongases suggest altered lipid metabolism in CM. A lower plasma ceramide level suggests reduced de novo synthesis or reduced sphingomyelin hydrolysis. Changes in CSF PAF suggest differences in brain lipid signaling pathways in CM. Together, this pilot study shows lipid metabolic abnormality in CM corresponding to altered energy homeostasis. We propose that controlling plasma lipolysis, desaturases, elongases, and lipid signaling pathways may relieve CM symptoms.

Cow's milk fat and child adiposity: a prospective cohort study

BACKGROUND

International guidelines recommend children aged 9 months to 2 years consume whole (3.25%) fat cow's milk, and children older than age 2 years consume reduced (0.1-2%) fat cow's milk to prevent obesity. The objective of this study was to evaluate the longitudinal relationship between cow's milk fat (0.1-3.25%) intake and body mass index z-score (zBMI) in childhood. We hypothesized that higher cow's milk fat intake was associated with lower zBMI.

METHODS

A prospective cohort study of children aged 9 months to 8 years was conducted through the TARGet Kids! primary care research network. The exposure was cow's milk fat consumption (skim (0.1%), 1%, 2%, whole (3.25%)), measured by parental report. The outcome was zBMI. Height and weight were measured by trained research assistants and zBMI was determined according to WHO growth standards. A linear mixed effects model and logistic generalized estimating equations were used to determine the longitudinal association between cow's milk fat intake and child zBMI.

RESULTS

Among children aged 9 months to 8 years (N = 7467; 4699 of whom had repeated measures), each 1% increase in cow's milk fat consumed was associated with a 0.05 lower zBMI score (95% CI -0.07 to -0.03, p < 0.0001) after adjustment for covariates including volume of milk consumed. Compared to children who consumed reduced fat (0.1-2%) milk, there was evidence that children who consumed whole milk had 16% lower odds of overweight (OR = 0.84, 95% CI 0.77 to 0.91, p < 0.0001) and 18% lower odds of obesity (OR = 0.82, 95% CI 0.68 to 1.00, p = 0.047).

CONCLUSIONS

Guidelines for reduced fat instead of whole cow's milk during childhood may not be effective in preventing overweight or obesity.

Omega-7 Mixed Fatty Acid Supplementation Fails to Reduce Serum Inflammatory Biomarkers: A Placebo-Controlled, Double-Blind Randomized Crossover Trial

We report the effects of mixed omega-7 fatty acid supplementation on changes in serum hsCRP, TNFα, and IL-6 levels and self-reported outcomes in people with non-specific chronic musculoskeletal discomfort. Design: A double-blind, placebo-controlled, 1:1 randomized single crossover trial composed of 688 mg/day palmiteolate for the verum and an equivalent amount of medium-chain triglycerides for the placebo. Method: Data were analyzed in two independent groups and as a crossover group. Results: From 211 screened participants in 2017–2019, 56 were randomized. Six participants dropped out and fifty completers contributed to the statistical analyses. At baseline, none of the investigated biomarkers were significantly correlated to subjectively assessed musculoskeletal discomfort levels. For the two-group analysis (n = 26 and n = 24), none of the serum biomarkers reached statistical significance; however, a statistically significant placebo effect was found in the subjective outcomes. Conclusion: For the crossover analysis (n = 50), three weeks of supplementation with n7FA containing 688 mg per day of palmiteolate did not reduce serum inflammatory biomarkers nor did it improve subjectively measured quality of life (QoL) compared to placebo. Future studies should explore appropriate biomarkers, sufficient power, length of dosing, inclusion criteria for volunteers with higher BMI, and the verification of cis-palmiteolate versus trans-palmiteolate.

Isomer-Resolved Imaging of Prostate Cancer Tissues Reveals Specific Lipid Unsaturation Profiles Associated With Lymphocytes and Abnormal Prostate Epithelia

Prostate cancer is the fourth most common cancer worldwide with definitive diagnosis reliant on biopsy and human-graded histopathology. As with other pathologies, grading based on classical haematoxylin and eosin (H&E) staining of formalin fixed paraffin-embedded material can be prone to variation between pathologists, prompting investigation of biomolecular markers. Comprising around 50% of cellular mass, and with known metabolic variations in cancer, lipids provide a promising target for molecular pathology. Here we apply isomer-resolved lipidomics in combination with imaging mass spectrometry to interrogate tissue sections from radical prostatectomy specimens. Guided by the histopathological assessment of adjacent tissue sections, regions of interest are investigated for molecular signatures associated with lipid metabolism, especially desaturation and elongation pathways. Monitoring one of the most abundant cellular membrane lipids within these tissues, phosphatidylcholine (PC) 34:1, high positive correlation was observed between the n-9 isomer (site of unsaturation 9-carbons from the methyl terminus) and epithelial cells from potential pre-malignant lesions, while the n-7 isomer abundance was observed to correlate with immune cell infiltration and inflammation. The correlation of lipid isomer signatures with human disease states in tissue suggests a future role for isomer-resolved mass spectrometry imaging in assisting pathologists with prostate cancer diagnoses and patient stratification.

Phytochemical Profiling in Conjunction with In Vitro and In Silico Studies to Identify Human α-Amylase Inhibitors in Leucaena leucocephala (Lam.) De Wit for the Treatment of Diabetes Mellitus

Bioactive constituents from natural sources are of great interest as alternatives to synthetic compounds for the treatment of various diseases, including diabetes mellitus. In the present study, phytochemicals present in Leucaena leucocephala (Lam.) De Wit leaves were identified by gas chromatography-mass spectrometry and further examined by qualitative and quantitative methods. α-Amylase enzyme activity assays were performed and revealed that L. leucocephala (Lam.) De Wit leaf extract inhibited enzyme activity in a dose-dependent manner, with efficacy similar to that of the standard α-amylase inhibitor acarbose. To determine which phytochemicals were involved in α-amylase enzyme inhibition, in silico virtual screening of the absorption, distribution, metabolism, excretion, and toxicity properties was performed and pharmacophore dynamics were assessed. We identified hexadecenoic acid and oleic acid ((Z)-octadec-9-enoic acid) as α-amylase inhibitors. The binding stability of α-amylase to those two fatty acids was confirmed in silico by molecular docking and a molecular dynamics simulation performed for 100 ns. Together, our findings indicate that L. leucocephala (Lam.) De Wit-derived hexadecanoic acid and oleic acid are natural product-based antidiabetic compounds that can potentially be used to manage diabetes mellitus.

Effects of omega-7 palmitoleic acids on skeletal muscle differentiation in a hyperglycemic condition

Maternal obesity and diabetes are known to be involved in fetal myogenesis, but the later stages of myogenesis are not well understood. In this study, we investigated the influence of a hyperglycemic environment on L6 skeletal myoblast differentiation and the function of omega-7 palmitoleic acids. Exposure to a high concentration of glucose (25 mM) in high-glucose culture medium (HG) increased the expression of myogenic genes (MyoD, Myogenin, MRF4, Myhc2x, and Myhc2a) and the synthesis of myosin. HG also activated the PI3K/AKT pathway revealed muscle cell differentiation. Furthermore, the levels of reactive oxygen species (ROS) and an inflammatory cytokine (Tnfaip3; tumor necrosis factor alpha-induced protein 3), which are crucial for the growth and differentiation of skeletal muscle, were increased by HG. Palmitoleic acids suppressed the expression levels of myogenic regulatory genes and increased the expression level of a cell proliferation-related gene (Pax3). Trans-palmitoleic acid and eicosapentaenoic acid (TPA and EPA) increased the phosphorylation level of MAPK/ERK1/2 and downregulated ROS generation and Tnfaip3 expression. In contrast, cis-palmitoleic acid inactivated MAPK/ERK1/2, leading to increased ROS generation. In conclusion, a hyperglycemic environment mediated by HG induced excessive muscle differentiation. Palmitoleic acids inhibited myoblast differentiation by downregulating muscle-specific genes. Moreover, trans-palmitoleic acids may have beneficial antioxidant and/or anti-inflammatory effects in cells.

Palmitoleate Protects against Zika Virus-Induced Placental Trophoblast Apoptosis

Zika virus (ZIKV) infection in pregnancy is associated with the development of microcephaly, intrauterine growth restriction, and ocular damage in the fetus. ZIKV infection of the placenta plays a crucial role in the vertical transmission from the maternal circulation to the fetus. Our previous study suggested that ZIKV induces endoplasmic reticulum (ER) stress and apoptosis of placental trophoblasts. Here, we showed that palmitoleate, an omega-7 monounsaturated fatty acid, prevents ZIKV-induced ER stress and apoptosis in placental trophoblasts. Human trophoblast cell lines (JEG-3 and JAR) and normal immortalized trophoblasts (HTR-8) were used. We observed that ZIKV infection of the trophoblasts resulted in apoptosis and treatment of palmitoleate to ZIKV-infected cells significantly prevented apoptosis. However, palmitate (saturated fatty acid) did not offer protection from ZIKV-induced ER stress and apoptosis. We also observed that the Zika viral RNA copies were decreased, and the cell viability improved in ZIKV-infected cells treated with palmitoleate as compared to the infected cells without palmitoleate treatment. Further, palmitoleate was shown to protect against ZIKV-induced upregulation of ER stress markers, C/EBP homologous protein and X-box binding protein-1 splicing in placental trophoblasts. In conclusion, our studies suggest that palmitoleate protects placental trophoblasts against ZIKV-induced ER stress and apoptosis.

Trans-palmitoleic acid reduces adiposity via increased lipolysis in a rodent model of diet-induced obesity

Obesity is defined as increased adiposity, which leads to metabolic disease. The growth of adipose tissue depends on its capacity to expand through hyperplasia or hypertrophy, in order to buffer energy surplus. Also, during the establishment of obesity, adipose tissue expansion reflects adipose lipid metabolism (lipogenesis and/or lipolysis). It is well known that dietary factors can modify lipid metabolism promoting or preventing the development of metabolic abnormalities that concur with obesity. Trans-palmitoleic acid (TP), a biomarker of dairy consumption, has been associated with reduced adiposity in clinical studies. Thus, we aimed to evaluate the effect of TP over adiposity and lipid metabolism-related genes in a rodent model of diet-induced obesity (DIO). To fulfil this aim, we fed C57BL/6 mice with a Control or a High-Fat diet, added with or without TP (3 g/kg diet), during 11 weeks. Body weight and food intake were monitored, fat pads were weighted, histology of visceral adipose tissue was analysed and lipid metabolism-related gene expression was explored by qPCR. Results show that TP consumption prevented weight gain induced by high-fat diet, reduced visceral adipose tissue weight and adipocyte size, while increasing the expression of lipolytic molecules. In conclusion, we show for the first time that TP influences adipose tissue metabolism, specifically lipolysis, resulting in decreased adiposity and reduced adipocyte size in a DIO mice model.

Oleic acid in Angus and Hanwoo (Korean native cattle) fat reduced the fatty acid synthase activity in rat adipose tissues

This study aimed to determine the blood lipid profiles, fatty acid composition, and lipogenic enzyme activities in rat adipose tissues as affected by the Angus beef fat (ABF) and Hanwoo beef fat (HBF) containing high oleic acid (OA) content. We assigned 60 Sprague Dawley rats with a mean bodyweight of 249 ± 3.04 g to three groups (n = 20 each) to receive diets containing 7% coconut oil (CON), 7% ABF, or 7% HBF. The OA content was highest in the HBF (45.23%) followed by ABF (39.51%) and CON (6.10%). The final body weight of the HBF-fed group was significantly increased, probably due to increased feed intake, indicating the palatability of the diet. The HBF and ABF significantly increased high-density lipoprotein cholesterol (HDL-C), decreased triglyceride (TG) and total cholesterol (TC) levels, and also tended to attenuate glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) levels in the bloodstream of the rats compared to CON. As compared to CON, lauric, myristic, and palmitic acids were significantly lower, and those of OA and α-linolenic acid (ALA) were significantly higher in the adipose tissues of HBF and ABF-fed groups. The HBF and ABF also reduced lipogenesis as induced by depleted fatty acid synthase (FAS) activity in rat adipose tissues. Nevertheless, between the two fats, HBF showed high feed intake due to its high palatability but reduced lipogenic enzyme activity, specifically that of FAS, and increased HDL-C, decreased TC and TG levels in the bloodstream, reduced saturated fatty acids (SFA), and increased oleic and ALA contents in rat adipose tissues indicating that HBF consumption does not pose significant risks of cardiovascular disease.

Plasma Free Fatty Acids and Metabolic Effect in Type 2 Diabetes, an Ancillary Study from a Randomized Clinical Trial

Most nutrition studies looking at the association of food with cardiometabolic markers rely on food frequency questionnaires, which are prone to recall bias. Pentadecanoic acid, heptadecanoic acid and trans-palmitoleic acid are fatty acids that are not synthesized endogenously but are obtained from the diet, particularly dairy, making them reasonable biomarkers of dairy consumption. We investigated the association of dairy fatty acid biomarkers with glycated hemoglobin (HbA1c) and cardiovascular risk factors in type 2 diabetes (T2D). In a clinical trial, 111 participants with T2D (age 58.5 ± 8.9 years, HbA1c 8.09 ± 0.96%) were randomized into three groups: a control group that maintained baseline dairy intake, a low-fat (LF) group that incorporated ≥3 servings/day of LF dairy and a high-fat (HF) group that incorporated ≥3 servings/day of HF dairy. We compared the fatty acids (FA) composition between the three groups at 24 weeks. Pentadecanoic acid and trans-palmitoleic acid increased in the HF group by 14.1% ± 5.4% and 17.5% ± 5.1%, respectively, but not in the control and LF groups (p = 0.0474 and p = 0.0025 for group-by-time interaction, respectively). Those increases were positively associated with changes in total cholesterol, very-low-density lipoprotein cholesterol VLDL-C and triglycerides but were not associated with changes in HbA1c from baseline to 24 weeks. These results suggest that the intervention was successful and that participants were likely compliant, which supports the validity of the main trial.

Trans triacylglycerols from dairy products and industrial hydrogenated oil exhibit different effects on the function of human umbilical vein endothelial cells via modulating phospholipase A2/arachidonic acid metabolism pathways

Dairy fat intake has been considered as a risk factor for cardiovascular disease. Rodent models show that trans fatty acids in industrial hydrogenated oil and ruminant milk have different effects on cardiovascular diseases. One of the main reasons is that the distributions of trans fatty acids in triacylglycerols from dairy products and from industrial hydrogenated oil are different, which affects lipid absorption and metabolism. This study investigated the effects of 1,3-olein-2-elaidin (OEO, representing industrial hydrogenated oil triacylglycerols) and 1-vaccenic-2,3-olein (OOV, representing ruminant triacylglycerols in dairy products) on the function of human umbilical vein endothelial cells (HUVEC), including cell viability, lactate dehydrogenase (LDH) exudation rate, and nitric oxide secretory and nitric oxide synthase relative activity. We found that the detrimental effect of OEO on HUVEC was significantly greater than that of OOV. The results also showed that the absorption rate of OEO in HUVEC (78.25%) was significantly greater than that of OOV (63.32%). Mechanistically, based on phospholipidomics analysis, we found that calcium-independent phospholipase A2 (iPLA2) played a key role with regard to the OOV-mediated arachidonic acid (ARA)/COX-2/PG pathway, whereas secretory phospholipase A2 (sPLA2) and cytoplasmic phospholipase A2 (cPLA2) are responsible for the OEO-mediated ARA/COX-2/PG pathway. Moreover, OEO had a greater effect on the protein expression of COX-2 and PG secretion than OOV. In addition, iPLA2, sPLA2, and cPLA2 could mediate the ARA/CYP4A11 pathway in OOV-treated HUVEC, but only iPLA2 could mediate this pathway in HUVEC treated with OEO. We also found that sPLA2 could mediate the ARA/5-LOX pathway in HUVEC treated with OOV, but none of these 3 forms of PLA2 could mediate this pathway in HUVEC treated with OEO. On the other hand, after OOV treatment, trans-11 C18:1 was converted to beneficial forms of fatty acids in HUVEC, including conjugated linoleic acid (CLA) and trans-9 C16:1. In conclusion, we elucidated the potential mechanisms that might account for the diverse effects of triacylglycerols from industrial hydrogenated oil and ruminant milk on the function of HUVEC.

MicroRNA-193a-5p Regulates the Synthesis of Polyunsaturated Fatty Acids by Targeting Fatty Acid Desaturase 1 (FADS1) in Bovine Mammary Epithelial Cells

Cardiovascular diseases (CVDs) are seriously threatening to human life and health. Polyunsaturated fatty acids (PUFAs) are known for their role in preventing CVDs. It is beneficial to population health to promote the content of PUFAs in bovine milk. In recent years, limited research based on molecular mechanisms has focused on this field. The biological roles of numerous microRNAs (miRNAs) remain unknown. In this study, a promising and negatively correlated pair of the miRNA (miRNA-193a-5p) and a fatty acid desaturase 1 (FADS1) gene are identified and screened to explore whether they are potential factors of PUFAs’ synthesis in bovine milk. The targeted relationship between miRNA-193a-5p and FADS1 in bovine mammary epithelial cells (BMECs) is demonstrated by dual luciferase reporter assays. qRT-PCR and western blot assays indicate that both the expression of mRNA and the protein FADS1 show a negative correlation with miRNA-193a-5p expression in BMECs. Also, miR-193a-5p expression is positively correlated with the expression of genes associated with milk fatty acid metabolism, including ELOVL fatty acid elongase 6 (ELOVL6) and diacylglycerol O-acyltransferase 2 (DGAT2). The expression of fatty acid desaturase 2 (FADS2) is negatively correlated with miR-193a-5p expression in BMECs. The contents of triglycerides (TAG), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) have a significant positive correlation with the expression of FADS1 and a significant negative correlation with the expression of miR-193a-5p in BMECs. For the first time, this study confirms that miRNA-193a-5p regulates PUFAs metabolism in BMECs by targeting FADS1, indicating that miRNA-193a-5p and FADS1 are underlying factors that improve PUFAs content in bovine milk.

Milk and Dairy Products Intake Is Related to Cognitive Impairment at Baseline in Predimed Plus Trial

SCOPE

To examine the association between milk and dairy products intake and the prevalence of cognitive decline among Spanish individuals at high cardiovascular risk.

METHODS AND RESULTS

Cross-sectional analyses are performed on baseline data from 6744 adults (aged 55-75 years old). Intake of milk and dairy products is estimated using a food frequency questionnaire grouped into quartiles. The risk of developing cognitive impairment is based on the Mini-Mental State Examination (MMSE). A higher prevalence of cognitive decline was found in subjects who consumed more grams. Patients with worse MMSE score (10-24) consumed a mean of 395.14 ± 12.21 g, while patients with better MMSE score (27-30) consumed a mean of 341.23 ± 2.73 g (p < 0.05). Those subjects with the lower milk consumption (<220 g/day) had a higher MMSE score (28.35 ± 0.045). Higher intake of fermented dairy products was observed in participants with a lower MMSE score (OR 1.340, p = 0.003). A positive correlation was found between the consumption of whole milk and the MMSE score (r = 0.066, p < 0.001).

CONCLUSIONS

These findings suggest that greater consumption of milk and dairy products could be associated with greater cognitive decline according to MMSE. Conversely, consumption of whole-fat milk could be linked with less cognitive impairment in the cross-sectional study.

Cis- and Trans-Palmitoleic Acid Isomers Regulate Cholesterol Metabolism in Different Ways

Hypercholesterolemia is a preventable risk factor for atherosclerosis and cardiovascular disease. However, the mechanisms whereby cis-palmitoleic acid (cPOA) and trans-palmitoleic acid (tPOA) promote cholesterol homeostasis and ameliorate hypercholesterolemia remain elusive. To investigate the effects of cPOA and tPOA on cholesterol metabolism and its mechanisms, we induced hypercholesterolemia in mice using a high-fat diet and then intragastrically administered cPOA or tPOA once daily for 4 weeks. tPOA administration reduced serum cholesterol, low-density lipoprotein, high-density lipoprotein, and hepatic free cholesterol and total bile acids (TBAs). Conversely, cPOA had no effect on these parameters except for TBAs. Histological examination of the liver, however, revealed that cPOA ameliorated hepatic steatosis more effectively than tPOA. tPOA significantly reduced the expression of 3-hydroxy-3-methyl glutaryl coenzyme reductase (HMGCR), LXRα, and intestinal Niemann-Pick C1-Like 1 (NPC1L1) and increased cholesterol 7-alpha hydroxylase (CYP7A1) in the liver, whereas cPOA reduced the expression of HMGCR and CYP7A1 in the liver and had no effect on intestinal NPC1L1. In summary, our results suggest that cPOA and tPOA reduce cholesterol synthesis by decreasing HMGCR levels. Furthermore, tPOA, but not cPOA, inhibited intestinal cholesterol absorption by downregulating NPC1L1. Both high-dose tPOA and cPOA may promote the conversion of cholesterol into bile acids by upregulating CYP7A1. tPOA and cPOA prevent hypercholesterolemia via distinct mechanisms.