Dietary Fatty Acid Composition Research Articles

Impact of Dietary Fatty Acid Composition on the Intestinal Microbiota and Fecal Metabolism of Rats Fed a High-Fructose/High-Fat Diet.

Background/Objectives: An inappropriate intake of dietary fats can disrupt the homeostasis of intestinal microbiota, affect the host's metabolic status, and increase the risk of chronic diseases. The impact of dietary fat types on the composition and metabolic functionality of the intestinal microbiota has become a research focus over recent years. The objective of this study was to explore the effects of regular peanut oil (PO) and high-oleic-acid peanut oil (HOPO) on the composition and metabolic function of the intestinal microbiota. Methods: A dietary intervention test was conducted on SD rats fed a high-fat/high-fructose (HFF) diet. The composition and metabolic functionality of the intestinal microbiota of the experimental rats were investigated by 16S rRNA gene sequencing and fecal metabolomics. Results: Compared with saturated fat, PO and HOPO enhanced the diversity of intestinal microbiota in HFF diet-fed rats. Compared with PO, HOPO significantly increased the relative abundance of Lachnospiraceae_NK4A136_group and Harryflintia (p < 0.05), which are able to generate butyrate and acetate. Compared with saturated fat, 318 and 271 fecal biomarkers were identified in PO and HOPO groups, respectively. In contrast, 68 fecal biomarkers were identified between the PO and HOPO groups. The inhibition of harmful proteolytic fermentation in the colon may represent the main regulatory mechanism. With regard to metabolic status, HOPO provided better control of body weight and insulin sensitivity than PO. Conclusions: Compared with saturated fat, peanut oils better regulated the composition and metabolic function of the intestinal microbiota. In addition, HOPO exhibited better regulatory effects than PO.

Gene therapy for fat-1 prevents obesity-induced metabolic dysfunction, cellular senescence, and osteoarthritis

Obesity is one of the primary risk factors for osteoarthritis (OA), acting through cross talk among altered biomechanics, metabolism, adipokines, and dietary free fatty acid (FA) composition. Obesity and aging have been linked to cellular senescence in various tissues, resulting in increased local and systemic inflammation and immune dysfunction. We hypothesized that obesity and joint injury lead to cellular senescence that is typically associated with increased OA severity or with aging and that the ratio of omega-6 (ω-6) to omega-3 (ω-3) FAs regulates these pathologic effects. Mice were placed on an ω-6-rich high-fat diet or a lean control diet and underwent destabilization of the medial meniscus to induce OA. Obesity and joint injury significantly increased cellular senescence in subcutaneous and visceral fat as well as joint tissues such as synovium and cartilage. Using adeno-associated virus (AAV) gene therapy for fat-1, a fatty acid desaturase that converts ω-6 to ω-3 FAs, decreasing the serum ω-6:ω-3 FA ratio had a strong senomorphic and therapeutic effect, mitigating metabolic dysfunction, cellular senescence, and joint degeneration. In vitro coculture of bone marrow-derived macrophages and chondrocytes from control and AAV8-fat1-treated mice were used to examine the roles of various FA mediators in regulating chondrocyte senescence. Our results suggest that obesity and joint injury result in a premature "aging" of the joint as measured by senescence markers, and these changes can be ameliorated by altering FA composition using fat-1 gene therapy. These findings support the potential for fat-1 gene therapy to treat obesity- and/or injury-induced OA clinically.

Associations between dietary fatty acid and plasma fatty acid composition in non-alcoholic fatty liver disease: secondary analysis from a randomised trial with a hypoenergetic low-carbohydrate high-fat and intermittent fasting diet.

Dietary fatty acids (FA) affect metabolic risk factors. The aim of this study was to explore if changes in dietary fat intake during energy restriction were associated with plasma FA composition. The study also investigated if these changes were associated with changes in liver fat, liver stiffness and plasma lipids among persons with non-alcoholic fatty liver disease. Dietary and plasma FA were investigated in patients with non-alcoholic fatty liver disease (n 48) previously enrolled in a 12-week-long open-label randomised controlled trial comparing two energy-restricted diets: a low-carbohydrate high-fat diet and intermittent fasting diet (5:2), to a control group. Self-reported 3 d food diaries were used for FA intake, and plasma FA composition was analysed using GC. Liver fat content and stiffness were measured by MRI and transient elastography. Changes in intake of total FA (r 0·41; P = 0·005), SFA (r 0·38; P = 0·011) and MUFA (r 0·42; P = 0·004) were associated with changes in liver stiffness. Changes in plasma SFA (r 0·32; P = 0·032) and C16 : 1n-7 (r 0·33; P = 0·028) were positively associated with changes in liver fat, while total n-6 PUFA (r -0·33; P = 0·028) and C20 : 4n-6 (r -0·42; P = 0·005) were inversely associated. Changes in dietary SFA, MUFA, cholesterol and C20:4 were positively associated with plasma total cholesterol and LDL-cholesterol. Modifying the composition of dietary fats during dietary interventions causes changes in the plasma FA profile in patients with non-alcoholic fatty liver disease. These changes are associated with changes in liver fat, stiffness, plasma cholesterol and TAG. Replacing SFA with PUFA may improve metabolic parameters in non-alcoholic fatty liver disease patients during weight loss treatment.

Plasma fatty acid levels and risk of non-small cell lung cancer: a large-scale prospective cohort study.

Non-small cell lung cancer (NSCLC) ranks among the most prevalent and lethal malignancies globally. Fatty acids (FAs) play a significant role in diverse physiological and pathological mechanisms, yet their precise involvement in NSCLC remains poorly understood. This study utilized a large-scale prospective cohort of 249,132 participants, observed over an average of 12 years, to investigate the relationship between different FAs and NSCLC risk. Analytical approaches included Cox proportional hazards regression, Kaplan-Meier survival analysis, accelerated failure time (AFT) modeling, and restricted cubic spline (RCS) analysis. During the follow-up period, 1,460 participants were diagnosed with NSCLC. Cox regression analysis demonstrated that elevated levels of docosahexaenoic acid (DHA), linoleic acid (LA), and omega-3 were inversely associated with NSCLC risk. Kaplan-Meier curves, along with AFT models, corroborated that elevated concentrations of DHA and LA significantly delayed NSCLC onset. Additionally, RCS analysis uncovered nuanced dose-response relationships between these FAs and NSCLC. Stratified analyses highlighted variability based on smoking status, gender, and body mass index subgroups. The concentration of specific FAs exhibits a significant association with NSCLC risk. These results offer a foundation for devising dietary FA composition adjustments aimed at reducing NSCLC risk.

Replacement of fish oil by palm oil in diet for juvenile greenfin horse-faced filefish (Thamnaconus septentrionalis): Effects on growth performance, fatty acid composition, antioxidant capacity and inflammatory responses

This study investigated the effects of replacing dietary fish oil (FO) with palm oil (PO) on the growth performance, proximate composition, antioxidant capacity, and inflammatory responses of juvenile greenfin horse-faced filefish, Thamnaconus septentrionalis. Five isonitrogenous and isocaloric diets with varying levels of PO inclusion (0%, 25%, 50%, 75%, and 100%) were prepared, and each diet was administered in triplicate to juvenile fish for 10 weeks. Results indicated that moderately partial replacement of FO did not result in detrimental effects whereas complete or high-level replacement of FO compromised survival, growth, and feed utilization. Moderate PO inclusion slightly increased the antioxidant capacity. However, this effect was significantly impaired by high levels of dietary PO. The moisture and ash content of whole fish showed an increasing trend, while crude lipid and crude protein content tended to decline, showing significant linear response. Dietary PO appeared to affect triglyceride synthesis, albeit with minimal impact on the lipid content of the liver. Fatty acid compositions in both liver and muscle tissues were linearly correlated with dietary FA profiles, with fish liver being more reflective of dietary fatty acid composition than muscle tissue. ARA, EPA and DHA were selectively retained in the muscle tissue, whereas EPA retention was significantly reduced in the liver tissue with the gradual replacement of FO. High levels of PO inclusion in the diet resulted in elevated gene expression related to hepatic inflammation, including TLRs, MyD88 and TNFa. In conclusion, palm oil could potentially serve as an alternative to fish oil in the diet for juvenile T. septentrionalis, with up to 50% substitution without deteriorating growth performance, n-3 LC-PUFA deposition in muscle, and health status of juvenile greenfin horse-faced filefish.

Modelling changes in whole body and fillet fatty acid composition of Atlantic salmon with changing levels of dietary omega-3 intake

In this study, a fatty acid dilution model was coupled with a dynamic nutrient demand model to provide an integrated model capable of predicting the whole-body and fillet lipid and fatty acid levels of Atlantic salmon (Salmo salar) following a change in dietary fatty acid profile. Based on knowledge of the initial fish and dietary fatty acid compositions, diet digestible energy density, the water temperature and duration of feeding, the model demonstrated that it was possible to predict a range of parameters, including the growth, feed utilisation, whole-body and fillet (Norwegian Quality Cut; NQC) total lipid, and fatty acid levels of the fish. The model was validated against five separate experiments, including two farm-based trials with harvest size fish. Validation experiments involved fish ranging in size (initial weights to final weights) from 138 g/fish to 5138 g/fish and running for durations of between 66 and 323 days. For the laboratory experiments, prediction of growth, feed utilisation and fatty acid deposition proved to be highly predictable (R2 > 0.998). Fatty acid profiles from both short and long-term cage trials were also highly predictable. Despite the reduced level of weight change in the short-term cage trial, and the higher variability that was observed in growth performance, the fatty acid deposition still showed high levels of correlation (R2 > 0.996), between the modelled and measured fatty acid levels in the fish fillet. Departure from linearity was more evident in the long-term cage trial, but correlation still exceeded R2 > 0.995 for all treatments. Prediction of whole-body and NQC total lipid levels was less accurate, with correlations being R2 = 0.962 and R2 = 0.909 respectively. Model outputs were generally more accurate with greater weight change and/or experiment duration. The outcome of this study shows that the model developed here provides a useful tool for the estimation of the fatty acid composition of Atlantic salmon following a change in dietary fatty acid composition. This could help assist in the more judicious use of dietary long-chain omega-3 fatty acids for commercial salmon farming.

PSIII-15 Effect of dietary fatty acids composition on growth performance, fecal consistency, and plasma fatty acid profile of weaned pigs

Abstract Dietary lipids are an important source of energy and fatty acids (FA), which have critical roles in mucosal immune responses, epithelial barrier functions, and overall intestinal development. Therefore, including fat in nursery pig diets can be used as a nutritional strategy to optimize pig growth performance and intestinal health after weaning. This study evaluated the effects of two different dietary fatty acid compositions derived from conventional soybean oil (CSO) and/or high oleic soybean oil (HOSO) supplementation on growth performance, fecal consistency, and plasma FA profile of weaned pigs. A total of 208 weaned pigs (body weights = 4.96 ± 0.8 kg) were used in a randomized complete block design and allotted to 16 pens of 13 pigs each. Experimental diets met NRC (2012) requirements and were provided in a 3-phase nursery feeding program: Phase 1 (d 0-d7), Phase 2 (d 8-d21), and Phase 3 (d 22-d42). Pens were assigned to one of two dietary treatments consisting of two dietary FA compositions derived from the supplementation of 3% of either CSO (20% Oleic acid; 50% Linoleic acid; 6% Linolenic acid) or HOSO (44% Oleic acid; 30% Linoleic acid; 3% Linolenic acid). Feed disappearance and body weight were measured at d 0, 21, and 42. Pen fecal score was assigned daily from d 0 to 21 and then 3 times per week until d 42. Blood samples were collected on d 21 (2 pigs/pen) for plasma FA profile analysis. Performance data were analyzed using T-TEST and fecal score using PROC FREQ procedures of SAS. From d 0 to 21, pigs fed CSO supplemented diets had a greater (P ≤ 0.05) body weight (8.6 vs. 7.4 kg) and daily gain (0.17 vs. 0.12 kg). In addition, daily feed intake and feed efficiency tended to be 23% and 16% greater in CSO-fed pigs, respectively. From d 21 to d 42, there were no differences between dietary treatments for growth performance. Overall nursery period, pigs fed CSO had greater (P ≤ 0.1) daily gain than HOSO pigs (0.34 vs. 0.30 kg). Pigs fed CSO had a greater (P ≤ 0.05) plasma concentration of palmitic, linoleic, and linolenic FA while pigs fed HOSO had a greater (P ≤ 0.05) plasma concentration of palmitoleic and oleic FA. There were no differences in fecal scores in wk 1 and 2. However, pigs fed CSO had less incidence of soft and watery feces (χ2 &amp;lt; 0.1) in wk 3 to 6. In conclusion, a greater dietary content of linoleic and linolenic FA promoted pig growth performance and reduced incidence of diarrhea after weaning compared with greater content of oleic FA.

Dietary fatty acids and incident hip fractures in cohorts of women and men. A relative validation and follow-up study

ObjectivesHip fractures are associated with a high burden of morbidity and mortality. Diet is essential for preventing fragility fractures, but the role of dietary fatty acids on the risk of hip fracture is uncertain. The aim was to investigate how intake of different dietary fatty acids relates to the risk of hip fracture. A relative validation of the long-term intake of dietary fatty acids estimated from food frequency questionnaires (FFQs) was also performed. Design, settings and participantsWe used data collected in two population-based cohorts, the Swedish Mammography Cohort and the Cohort of Swedish men (n = 83,603, 54% men, aged 45–82 years). Data from the repeated investigations in the cohorts and cross-sectional data from their clinical sub-cohorts were used. MeasurementsDiet data was collected in FFQs. Incident hip fractures were gathered by individual linkage to national registers. We performed Cox regression analysis to investigate associations between dietary fatty acids and hip fracture. Follow-up time was between January 1st, 1998 and December 31st, 2020. The validation was performed using correlation analyses, comparing fatty acids measured in adipose tissue with estimated fatty acid intakes from FFQs. ResultsDuring up to 23 years of follow-up (mean 18 years) and 1,538,627 person-years at risk, 7345 participants (2840 men) experienced a hip fracture. A low linoleic acid (LA) and high intakes of long-chain n-3 fatty acids were associated with higher hip fracture risk in a non-linear way. In quartile 4 compared to quartile 1 of LA, the multivariable-adjusted hazard ratio of hip fracture was 0.89 (95% Confidence Interval: 0.81, 0.97). The study confirmed the validity of FFQs to capture the intake of the specific dietary long-chain n-3 fatty acids. The estimated intake of LA, α-linolenic acid, and myristic acid were also adequately captured by the FFQs. Validity was confirmed in both women and men. ConclusionA low to moderate intake of linoleic acid and a higher intake of long-chain n-3 fatty acids were associated with a higher risk of hip fractures. The results indicate that attention should be paid to dietary fatty acid composition for the optimal prevention of fragility fractures.

Maternal dietary fatty acid composition and content prior to and during pregnancy and lactation influences serum profile, liver phenotype and hepatic miRNA expression in young male and female offspring

This study aimed to investigate whether modifying the pre-gestational lipid content could mitigate metabolic damage in offspring from dams exposed to a high-fat (HF) diet before conception and during pregnancy and lactation, with a focus on sex-specific outcomes. Specific effects of maternal normolipidic diets on offspring were also assessed. Female Wistar rats received control (C) or HF diets before conception. During pregnancy and lactation, females were distributed in five groups: C-C, HF-HF, HF-C, HF-saturated (HF-S) or HF-polyunsaturated n-3 group (HF-P). Saturated and PUFA n-3 diets were normolipidic. In 21-day-old offspring, corporal parameters, adiposity, serum metabolites, OGTT, liver phenotype, and miR-34a-5p hepatic expression were determined. Pre-gestational HF diet impaired glycemic response in females, independent of any change in body weight. Female and male offspring from dams continuously exposed to HF diet exhibited hyperglycemia, increased adiposity, and disrupted serum lipid profiles. Male offspring showed increased hepatic fat accumulation and miR-34a-5p expression. Shifting maternal dietary lipid content to normolipidic diets restored offspring's phenotype; however, decreased SIRT1, IRβ and IRS1 expression in offspring from dams exposed to HF diet before conception suggested early indicators of glucose metabolism damage. Our findings indicated a pronounced metabolic impact on males. In conclusion, glucose tolerance impairment in females before conception disturbed intrauterine environment, influencing in offspring's phenotype. Modifying maternal dietary lipid content mitigated effects of pre-gestational HF diet exposure on young offspring. Nevertheless, decreased hepatic levels of critical insulin signaling proteins indicated that independently of the maternal diet, pre-existing HF diet-induced glucose intolerance before conception may adversely program the offspring's phenotype.

Associations between dietary fatty acids intake and abdominal aortic calcification: a national population-based study

BackgroundAbdominal aortic calcification (AAC) is a crucial indicator of cardiovascular health. This study aims investigates the associations between dietary fatty acid intake and AAC.MethodsIn this study, a cross-sectional assessment was performed on a group of 2,897 individuals aged 40 and above, utilizing data from the NHANES. The focus was on examining dietary consumption of various fatty acids, including Saturated (SFA), Monounsaturated (MUFA), Polyunsaturated (PUFA), as well as Omega-3 and Omega-6. The evaluation of AAC was done by applying the Kauppila AAC score to results obtained from dual-energy X-ray absorptiometry scans. For statistical analysis, weighted multivariate linear and logistic regression were employed, with adjustments for variables like gender, age, ethnicity, and overall health condition.ResultsParticipants with higher intake of SFA and PUFA showed a positive association with AAC score, while higher levels of dietary Omega-3 and Omega-6 fatty acids was connected with a negative correlation. Subgroup analyses indicated consistent associations across different sexes and age groups. The study found that an increase in SFA and PUFA intake correlated with an increase in AAC score, whereas Omega-3 and Omega-6 intake correlated with a decrease.ConclusionThis study underscores the importance of dietary fatty acid composition in the prevalence of AAC and its potential implications for dietary guidelines and cardiovascular disease prevention strategies.

Experimental evidence that EPA and DHA are dietary requirements in a migratory shorebird, but they do not affect muscle oxidative capacity.

Dietary n-3 long chain polyunsaturated fatty acids (LCPUFAs) are hypothesized to be natural doping agents in migratory shorebirds, enabling prolonged flight by increasing membrane fluidity and oxidative capacity of the flight muscles. Animals can obtain n-3 LCPUFAs from the diet or by conversion of dietary α-linolenic acid, 18:3 n-3. However, the capacity to meet n-3 LCPUFA requirements from 18:3 n-3 varies among species. Direct tests of muscle oxidative enhancement and fatty acid conversion capacity are lacking in marine shorebirds that evolved eating diets rich in n-3 LCPUFAs. We tested whether the presence and type of dietary fatty acids influence the fatty acid composition and flight muscle oxidative capacity in western sandpipers (Calidris mauri). Sandpipers were fed diets low in n-3 PUFAs, high in 18:3 n-3, or high in n-3 LCPUFAs. Dietary fatty acid composition was reflected in multiple tissues, and low intake of n-3 LCPUFAs decreased the abundance of these fatty acids in all tissues, even with a high intake of 18:3 n-3. This suggests that 18:3 n-3 cannot replace n-3 LCPUFAs, and dietary n-3 LCPUFAs are required for sandpipers. Flight muscle indicators of enzymatic oxidative capacity and regulators of lipid metabolism did not change. However, the n-3 LCPUFA diet was associated with increased FAT/CD36 mRNA expression, potentially benefitting fatty acid transport during flight. Our study suggests that flight muscle lipid oxidation is not strongly influenced by n-3 PUFA intake. The type of dietary n-3 PUFA strongly influences the abundance of n-3 LCPUFAs in the body and could still impact whole-animal performance.

Dietary fatty acid composition drives neuroinflammation and impaired behavior in obesity

Nutrient composition in obesogenic diets may influence the severity of disorders associated with obesity such as insulin-resistance and chronic inflammation. Here we hypothesized that obesogenic diets rich in fat and varying in fatty acid composition, particularly in omega 6 (ω6) to omega 3 (ω3) ratio, have various effects on energy metabolism, neuroinflammation and behavior. Mice were fed either a control diet or a high fat diet (HFD) containing either low (LO), medium (ME) or high (HI) ω6/ω3 ratio. Mice from the HFD-LO group consumed less calories and exhibited less body weight gain compared to other HFD groups. Both HFD-ME and HFD-HI impaired glucose metabolism while HFD-LO partly prevented insulin intolerance and was associated with normal leptin levels despite higher subcutaneous and perigonadal adiposity. Only HFD-HI increased anxiety and impaired spatial memory, together with increased inflammation in the hypothalamus and hippocampus. Our results show that impaired glucose metabolism and neuroinflammation are uncoupled, and support that diets with a high ω6/ω3 ratio are associated with neuroinflammation and the behavioral deterioration coupled with the consumption of diets rich in fat.

The association between prepregnancy dietary fatty acids and risk of gestational diabetes mellitus: A prospective cohort study

Background & aimsEpidemiologic studies have examined the association between dietary fatty acids and type 2 diabetes risk in general populations. Evidence regarding their associations with gestational diabetes mellitus (GDM) risk remains limited. This study aimed to evaluate prepregnancy fatty acids intake in relation to GDM risk. Methods3,725 pregnant women from the Xi’an Birth Cohort Study who were free of previous GDM or pre-existing chronic diseases were included. Dietary intake of total fat and individual fatty acids (including saturated fatty acids [SFA], monounsaturated fatty acids [MUFA], polyunsaturated fatty acids [PUFA], and trans fatty acids) during the year preceding pregnancy was assessed by a validated food-frequency questionnaire before 16 weeks of gestation. GDM was confirmed based on the 75-g oral glucose tolerance test. Log-binomial or modified Poisson regression models were applied to estimate the relative risks (RRs) and 95% confidence intervals (95%CIs) of GDM for fatty acids intake. Generalized linear regression was adopted for blood glucose levels with fatty acids intake. Results644 (17.3%) incident GDM cases were confirmed in our study. Participants in the highest intake of total fat substituting for carbohydrates had a 33% reduced risk of GDM than those in the lowest intake (RR:0.67;95%CI:0.55,0.81). For individual fatty acids, only PUFA intake was associated with a lower risk of GDM, with RR comparing extreme tertiles of 0.61 (95%CI:0.49,0.76). Each 2% increase in energy from total fat and PUFA replacing carbohydrates decreased the risk of GDM by 6% (95%CI:3%,9%) and 15% (95%CI:9%,21%), respectively. Similar inverse associations with intake of total fat and PUFA were observed for blood glucose levels. Further analyses of SFA substitution showed that replacement of 2% energy from SFA with PUFA and MUFA was associated with 26% (RR:0.74;95%CI:0.62,0.88) and 30% (RR:0.70;95%CI:0.50, 0.98) decreased risk of GDM, respectively. ConclusionsGreater intake of total fat and PUFA before pregnancy was associated with lower risk of GDM when replacing carbohydrates. Substitution SFA with PUFA and MUFA was also inversely associated with GDM risk. These findings support the important role of optimal dietary fatty acids composition in the prevention of GDM.

Dietary fatty acids and gallstone risk: insights from NHANES and Mendelian randomization analysis.

Prior research suggests polyunsaturated fatty acids (PUFA) may prevent gallstones, but evidence on saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) is limited. This study aims to explore the associations between fatty acids and gallstones using a large sample of American population and Mendelian randomization (MR) methods. The cross-sectional study involved 6,629 participants from the National Health and Nutrition Examination Survey (NHANES) 2017-2020. Logistic regression and restricted cubic spline (RCS) analysis were conducted after stratifying by gender subgroups. Two-sample MR analysis was used to explore the causal relationship between fatty acids and gallstones without confounding factors. In females, higher SFA intake was positively associated with gallstone risk, while higher intake of n-3 and n-6 PUFA was negatively associated. No significant associations were found in males. No nonlinear correlations were found in any group by RCS analysis. MR analysis indicated that SFA, n-3, and n-6 PUFA could reduce gallstone risk. The influence of dietary fatty acid composition on gallstone development differs by gender, providing insights into dietary prevention and treatment of gallstones.

Oleic Acid Promotes the Biosynthesis of 10-Hydroxy-2-decenoic Acid via Species-Selective Remodeling of TAGs in Apis mellifera ligustica.

This study aimed to assess the impact of oleic acid (OA) supplementation on the biosynthesis of 10-hydroxy-2-decenoic acid (10-HDA) in Apis mellifera ligustica. In experiment 1, varying concentrations of OA (2%, 4%, 6% and 8%) were added to an artificial diet for newly emerged bees reared in cages. Analysis of 10-HDA content and gene expression in the mandibular gland (MG) revealed that the 8% OA treatment had the greatest impact on promoting the synthesis of 10-HDA. Subsequent investigations utilized RNA-seq and lipidomics to characterize the molecular signature in the MG after feeding the 8% OA diet. Phosphatidylcholine (PC) and triacylglycerol (TAG) were found to be the predominant lipids in the MG of worker bees. A total of 154 TAGs were identified, with TAG (18:1-18:1-18:1) exhibiting the highest abundance, which increased by 1.5 times. The major TAG species contained palmitic acid (16:0) and oleic acid (18:1) in their structure, which was associated with fatty acid composition of diet. The increase in abundance of main TAGs may be attributed to the upregulation of glycerol-3-phosphate acyltransferase (Gpat) and glycerol kinase (GK) gene expression at the transcriptional level. The upregulation of differentially expressed genes (DEGs) related to carbohydrate metabolism may contribute to meeting the heightened metabolic demands of the MGs in worker bees. Royal jelly (RJ) samples from bee colonies fed with the 8% OA diet exhibited higher 10-HDA level than RJ collected from bee colonies fed with the artificial diet. These results indicate that 8% OA addition in the diet enhanced biosynthesis of 10-HDA in the mandibular gland, which was accompanied by significant and highly species-selective remodeling of TAGs.

Dietary palmitic acid to oleic acid ratio modulates energy metabolism and biological rhythms in young healthy Japanese males.

The present study investigated the potential role of the composition of dietary fatty acids in the regulation of biological rhythms, such as the sleep architecture, core body temperature and leukocyte clock gene expression, in subjects fed meals rich in palmitic acid (PA) or oleic acid (OA). Eleven males participated in two sessions of indirect calorimetry in a whole-room metabolic chamber. In each session, subjects consumed three meals rich in PA (44·3 % of total fat as PA and 42·3 % as OA) or OA (11·7 % of total fat as PA and 59·3 % as OA) in the metabolic chamber. The ratio of PA to OA in plasma was significantly lower and fat oxidation was significantly higher during 24 h of indirect calorimetry in the session with meals rich in OA than in that with meals rich in PA. The duration of slow wave sleep (SWS) was shorter, the latency of SWS was longer and the nadir of core body temperature after bedtime was later in the session with meals rich in PA than in that with meals rich in OA. The peak in CRY1 gene expression was earlier and its amplitude was higher in the session with meals rich in PA than in that with meals rich in OA. In healthy young males, meals rich in PA decreased fat oxidation and disrupted biological rhythms, particularly the sleep architecture and core body temperature during sleep, more than meals rich in OA.

Dietary fat differentially modulates the response of bone marrow-derived macrophages to TLR4 and NOD2 agonists.

Consumption of diets high in fat has been linked to the development of obesity and related metabolic complications. Such associations originate from the enhanced, chronic, low-grade inflammation mediated by macrophages in response to translocated bacteria, bacterial products, or dietary constituents such as fatty acids (FAs). Nucleotide-binding Oligomerization Domain 2 (NOD2) senses muramyl dipeptide (MDP), a component of bacterial peptidoglycan. The inability to sense peptidoglycan through NOD2 has been demonstrated to lead to dysbiosis, increased bacterial translocation, inflammation and metabolic dysfunction. Currently, it is unknown how consumption of HFDs with different FA compositions might influence NOD2-dependent responses. In this study, we subjected WT mice to a control diet or to HFDs comprised of various ratios of unsaturated to saturated fats and determined the macrophage response to TLR4 and NOD2 agonists. A HFD with equal ratios of saturated and unsaturated fats enhanced subsequent responsiveness of macrophages to LPS but not to MDP. However, a high-unsaturated fat diet (HUFD) or a high-saturated fat diet (HSFD) both decreased the responsiveness to NOD2 agonists compared to that observed in control diet (CD) fed mice. These data suggest that dietary fatty acid composition can influence the subsequent macrophage responsiveness to bacterial products.

Dietary Long-Chain Fatty Acids Accelerate Metabolic Dysfunction in Guinea Pigs with Non-Alcoholic Steatohepatitis.

The composition of dietary fatty acids may be important for the development and progression of metabolic syndrome and non-alcoholic steatohepatitis (NASH). This study investigated the effect of two high-fat diets based on coconut oil, containing predominantly medium-chain fatty acids (MCFA), or cocoa butter, containing mainly long-chain fatty acids (LCFA), on glucose homeostasis and NASH in guinea pigs following 16 and 32 weeks of diet. At week 16, glucose intolerance was increased in the LCFA animals compared to the MCFA animals (p < 0.001), with both groups differing from the controls by week 32 (p < 0.0001), supported by increased hemoglobin A1c (p < 0.05). NASH was present in both high-fat groups from week 16, with advancing fibrosis appearing more progressive in the LCFA animals at week 16. In agreement, gene expression showed overall increased expression of NASH target genes in the LCFA animals compared to the MCFA animals at weeks 16 and 32 (p < 0.05 and p < 0.0001, respectively). The LCFA animals also displayed increased plasma uric acid at both time points (p < 0.05), a phenomenon linked to NASH in humans. In conclusion, this study reports that a diet high in LCFA promotes metabolic imbalance and may accelerate NASH-associated hepatic fibrosis. This highlights the importance of a critical evaluation of fatty acid composition when investigating NASH-associated endpoints.

Association Between Dietary Fatty Acid Composition and Diabetes Kidney Disease: Systematic Review, Meta-analysis and Trial Sequential Analysis of Observational Studies

Association Between Dietary Fatty Acid Composition and Diabetes Kidney Disease: Systematic Review, Meta-analysis and Trial Sequential Analysis of Observational Studies

Impact of dietary fat levels and fatty acid composition on milk fat synthesis in sows at peak lactation

BackgroundDietary fat is important for energy provision and immune function of lactating sows and their progeny. However, knowledge on the impact of fat on mammary transcription of lipogenic genes, de novo fat synthesis, and milk fatty acid (FA) output is sparse in sows. This study aimed to evaluate impacts of dietary fat levels and FA composition on these traits in sows. Forty second-parity sows (Danish Landrace × Yorkshire) were assigned to 1 of 5 dietary treatments from d 108 of gestation until weaning (d 28 of lactation): low-fat control diet (3% added animal fat); or 1 of 4 high-fat diets with 8% added fat: coconut oil (CO), fish oil (FO), sunflower oil (SO), or 4% octanoic acid plus 4% FO (OFO). Three approaches were taken to estimate de novo milk fat synthesis from glucose and body fat.ResultsDaily intake of FA was lowest in low-fat sows within fat levels (P < 0.01) and in OFO and FO sows within high-fat diets (P < 0.01). Daily milk outputs of fat, FA, energy, and FA-derived carbon reflected to a large extent the intake of those. On average, estimates for de novo fat synthesis were 82 or 194 g/d from glucose according to method 1 or 2 and 255 g de novo + mobilized FA/d according to method 3. The low-fat diet increased mammary FAS expression (P < 0.05) and de novo fat synthesis (method 1; P = 0.13) within fat levels. The OFO diet increased de novo fat synthesis (method 1; P < 0.05) and numerically upregulated mammary FAS expression compared to the other high-fat diets. Across diets, a daily intake of 440 g digestible FA minimized milk fat originating from glucose and mobilized body fat.ConclusionsSows fed diets with low-fat or octanoic acid, through upregulating FAS expression, increased mammary de novo fat synthesis whereas the milk FA output remained low in sows fed the low-fat diet or high-fat OFO or FO diets, indicating that dietary FA intake, dietary fat level, and body fat mobilization in concert determine de novo fat synthesis, amount and profiles of FA in milk.