Dietary Linoleic Acid: Will Modifying Dietary Fat Quality Reduce the Risk of Type 2 Diabetes?
Ontology highlight
ABSTRACT:
SUBMITTER: Schulze MB
PROVIDER: S-EPMC8740926 | biostudies-literature | 2021 Sep
REPOSITORIES: biostudies-literature
Publications
Dietary Linoleic Acid: Will Modifying Dietary Fat Quality Reduce the Risk of Type 2 Diabetes?
Diabetes care 20210820 9
Similar Datasets
Project description:OBJECTIVE:To investigate whether the genetic burden of type 2 diabetes modifies the association between the quality of dietary fat and the incidence of type 2 diabetes. DESIGN:Individual participant data meta-analysis. DATA SOURCES:Eligible prospective cohort studies were systematically sourced from studies published between January 1970 and February 2017 through electronic searches in major medical databases (Medline, Embase, and Scopus) and discussion with investigators. REVIEW METHODS:Data from cohort studies or multicohort consortia with available genome-wide genetic data and information about the quality of dietary fat and the incidence of type 2 diabetes in participants of European descent was sought. Prospective cohorts that had accrued five or more years of follow-up were included. The type 2 diabetes genetic risk profile was characterized by a 68-variant polygenic risk score weighted by published effect sizes. Diet was recorded by using validated cohort-specific dietary assessment tools. Outcome measures were summary adjusted hazard ratios of incident type 2 diabetes for polygenic risk score, isocaloric replacement of carbohydrate (refined starch and sugars) with types of fat, and the interaction of types of fat with polygenic risk score. RESULTS:Of 102 305 participants from 15 prospective cohort studies, 20 015 type 2 diabetes cases were documented after a median follow-up of 12 years (interquartile range 9.4-14.2). The hazard ratio of type 2 diabetes per increment of 10 risk alleles in the polygenic risk score was 1.64 (95% confidence interval 1.54 to 1.75, I2=7.1%, τ2=0.003). The increase of polyunsaturated fat and total omega 6 polyunsaturated fat intake in place of carbohydrate was associated with a lower risk of type 2 diabetes, with hazard ratios of 0.90 (0.82 to 0.98, I2=18.0%, τ2=0.006; per 5% of energy) and 0.99 (0.97 to 1.00, I2=58.8%, τ2=0.001; per increment of 1 g/d), respectively. Increasing monounsaturated fat in place of carbohydrate was associated with a higher risk of type 2 diabetes (hazard ratio 1.10, 95% confidence interval 1.01 to 1.19, I2=25.9%, τ2=0.006; per 5% of energy). Evidence of small study effects was detected for the overall association of polyunsaturated fat with the risk of type 2 diabetes, but not for the omega 6 polyunsaturated fat and monounsaturated fat associations. Significant interactions between dietary fat and polygenic risk score on the risk of type 2 diabetes (P>0.05 for interaction) were not observed. CONCLUSIONS:These data indicate that genetic burden and the quality of dietary fat are each associated with the incidence of type 2 diabetes. The findings do not support tailoring recommendations on the quality of dietary fat to individual type 2 diabetes genetic risk profiles for the primary prevention of type 2 diabetes, and suggest that dietary fat is associated with the risk of type 2 diabetes across the spectrum of type 2 diabetes genetic risk.
| S-EPMC6652797 | biostudies-other
Project description:ObjectiveTo study plasma and dietary linoleic acid (LA) in relation to type 2 diabetes risk in post-myocardial infarction (MI) patients.Research design and methodsWe included 3,257 patients aged 60-80 years (80% male) with a median time since MI of 3.5 years from the Alpha Omega Cohort and who were initially free of type 2 diabetes. At baseline (2002-2006), plasma LA was measured in cholesteryl esters, and dietary LA was estimated with a 203-item food-frequency questionnaire. Incident type 2 diabetes was ascertained through self-reported physician diagnosis and medication use. Hazard ratios (with 95% CIs) were calculated by Cox regressions, in which dietary LA isocalorically replaced the sum of saturated (SFA) and trans fatty acids (TFA).ResultsMean ± SD circulating and dietary LA was 50.1 ± 4.9% and 5.9 ± 2.1% energy, respectively. Plasma and dietary LA were weakly correlated (Spearman r = 0.13, P < 0.001). During a median follow-up of 41 months, 171 patients developed type 2 diabetes. Plasma LA was inversely associated with type 2 diabetes risk (quintile [Q]5 vs. Q1: 0.44 [0.26, 0.75]; per 5%: 0.73 [0.62, 0.86]). Substitution of dietary LA for SFA+TFA showed no association with type 2 diabetes risk (Q5 vs. Q1: 0.78 [0.36, 1.72]; per 5% energy: 1.18 [0.59, 2.35]). Adjustment for markers of de novo lipogenesis attenuated plasma LA associations.ConclusionsIn our cohort of post-MI patients, plasma LA was inversely related to type 2 diabetes risk, whereas dietary LA was not related. Further research is needed to assess whether plasma LA indicates metabolic state rather than dietary LA in these patients.
| S-EPMC6971780 | biostudies-literature
Project description:De novo beige adipocyte biogenesis involves the proliferation of progenitor cells in white adipose tissue (WAT); however, what regulates this process remains unclear. Here, we report that in mouse models but also in human tissues, WAT lipolysis-derived linoleic acid triggers beige progenitor cell proliferation following cold acclimation, β3-adrenoceptor activation, and burn injury. A subset of adipocyte progenitors, as marked by cell surface markers PDGFRα or Sca1 and CD81, harbored cristae-rich mitochondria and actively imported linoleic acid via a fatty acid transporter CD36. Linoleic acid not only was oxidized as fuel in the mitochondria but also was utilized for the synthesis of arachidonic acid-derived signaling entities such as prostaglandin D2. Oral supplementation of linoleic acid was sufficient to stimulate beige progenitor cell proliferation, even under thermoneutral conditions, in a CD36-dependent manner. Together, this study provides mechanistic insights into how diverse pathophysiological stimuli, such as cold and burn injury, promote de novo beige fat biogenesis.
| S-EPMC9875052 | biostudies-literature
Project description:ObjectiveTo investigate the association between intakes of n-6 polyunsaturated fatty acids (PUFAs) and type 2 diabetes risk in three prospective cohort studies of U.S. men and women.Research design and methodsWe followed 83,648 women from the Nurses' Health Study (NHS) (1980-2012), 88,610 women from NHSII (1991-2013), and 41,771 men from the Health Professionals Follow-Up Study (HPFS) (1986-2012). Dietary data were collected every 2-4 years by using validated food-frequency questionnaires. Self-reported incident diabetes, identified biennially, was confirmed by using a validated supplementary questionnaire.ResultsDuring 4.93 million person-years of follow-up, 18,442 type 2 diabetes cases were documented. Dietary n-6 PUFAs accounted for 4.4-6.8% of total energy, on average, and consisted primarily of linoleic acid (LA) (≥98%). In multivariate-adjusted models, hazard ratios (95% CIs) of type 2 diabetes risk comparing extreme n-6 PUFA quintiles (highest vs. lowest) were 0.91 (0.85, 0.96) (P trend = 0.002) for total n-6 PUFAs and 0.92 (0.87, 0.98) (P trend = 0.01) for LA. In an isocaloric substitution model, diabetes risk was 14% (95% CI 5%, 21%) (P = 0.002) lower when LA isocalorically replaced saturated fats (5% of energy), 17% (95% CI 9%, 24%) (P < 0.001) lower for trans fats (2% of energy), or 9% (95% CI 17%, 0.1%) (P = 0.047) lower for carbohydrates (5% of energy). Replacing n-3 PUFAs or monounsaturated fats with LA was not significantly associated with type 2 diabetes risk.ConclusionsOur study provides additional evidence that LA intake is inversely associated with risk of type 2 diabetes, especially when replacing saturated fatty acids, trans fats, or carbohydrates.
| S-EPMC6647042 | biostudies-literature
Project description:BackgroundDietary n-3 PUFAs are inversely associated with risk of sudden cardiac death (SCD); however, little is known about other fats and SCD. Furthermore, concerns have been raised that high n-6 PUFA intake may attenuate the benefits of n-3 PUFAs.ObjectiveWe examined associations and selected interactions between dietary fatty acids, expressed as a proportion of total fat and SCD.DesignWe conducted a prospective cohort study among 91,981 women aged 34-59 y from the Nurses' Health Study in 1980. Over 30 y, we documented 385 SCDs.ResultsIn multivariable models, women in the highest compared with the lowest quintile of SFA intake had an RR of SCD of 1.44 (95% CI: 1.04, 1.98). Conversely, women in the highest compared with the lowest quintile of PUFA intake had an RR of SCD of 0.57 (95% CI: 0.41, 0.78). Intakes of n-6 and n-3 PUFAs were both significantly associated with a lower risk of SCD, and n-6 PUFAs did not modify the association between n-3 PUFAs and SCD. MUFAs and trans fats were not associated with SCD risk. After further adjustment for coronary heart disease (CHD) and CHD risk factors potentially in the causal pathway, the association between PUFAs and SCD remained significant, whereas the association for SFAs was no longer significant.ConclusionsIntake of PUFAs as a proportion of fat was inversely associated with SCD risk, independent of traditional CHD risk factors. These results support dietary guidelines to improve dietary fat quality by replacing intake of SFAs with n-6 and n-3 PUFAs.
| S-EPMC3417213 | biostudies-literature
Project description:IntroductionThe variants rs10517086 and rs1534422 are predictive of type 1 diabetes mellitus (T1DM) development and poor residual β cell function within the first year of diagnosis. However, the mechanism by which risk is conferred is unknown. We explored the impact of both variants on β cell function in vitro and assessed their relationship with C-peptide in people with T1DM and type 2 diabetes mellitus (T2DM).MethodsUsing CRISPR/Cas9, the variants were introduced into a β cell line (BRIN-BD11) and a T cell line (Jurkat cells) from which the conditioned media was applied to otherwise healthy β cells to model the inflammatory environment associated with these variants.ResultsBoth variants significantly reduced glucose-stimulated insulin secretion, increased production of pro-inflammatory cytokines and reduced expression of several β cell markers and transcription factors (KCNJ11, KCNQ1, SCL2A2, GCK, NKX6.1, Pdx1 NGN3). However, HNF1A was significantly upregulated in the presence of both variants. We subsequently silenced HNF1A in variant expressing BRIN-BD11 cells using siRNA and found that gene expression profiles were normalised. Induction of each variant significantly increased expression of the lncRNAs they encode, which was normalised upon HNF1A silencing. Analysis of the DARE (Diabetes Alliance for Research in England) study revealed an association of rs10517086_A genotype with C-peptide in 153 individuals with T1DM, but not in 417 people with T2DM.ConclusionsThese data suggest that rs1534422 and rs10517086 exert multiple insults on the β cell through excessive upregulation of HNF1A and induction of pro-inflammatory cytokines, and highlight their utility as prognostic markers of β cell function.
| S-EPMC11855905 | biostudies-literature
Project description:Linoleic acid (LA, 18:2n-6) is a precursor to arachidonic acid (AA, 20:4n-6), which can be converted by brain lipoxygenase and cyclooxygenase (COX) enzymes into various lipid mediators involved in the regulation of brain immunity. Brain AA metabolism is activated in rodents by the bacterial endotoxin, lipopolysaccharide (LPS). This study tested the hypothesis that dietary LA lowering, which limits plasma supply of AA to the brain, reduces LPS-induced upregulation in brain AA metabolism. Male Fischer CDF344 rats fed an adequate LA (5.2 % energy (en)) or low LA (0.4 % en) diet for 15 weeks were infused with LPS (250 ng/h) or vehicle into the fourth ventricle for 2 days using a mini-osmotic pump. The incorporation rate of intravenously infused unesterified 14C-AA into brain lipids, eicosanoids, and activities of phospholipase A2 and COX-1 and 2 enzymes were measured. Dietary LA lowering reduced the LPS-induced increase in prostaglandin E2 concentration and COX-2 activity (P < 0.05 by two-way ANOVA) without altering phospholipase activity. The 14C-AA incorporation rate into brain lipids was decreased by dietary LA lowering (P < 0.05 by two-way ANOVA). The present findings suggest that dietary LA lowering reduced LPS-induced increase in brain markers of AA metabolism. The clinical utility of LA lowering in brain disorders should be explored in future studies.
| S-EPMC5843819 | biostudies-literature
Project description:Liver fat accumulation is an important pathophysiological feature of non-alcoholic fatty liver disease that may be modulated by dietary supplements (DS). A systematic search of the literature was conducted for randomized controlled trials (RCTs) pertaining to the effect of a DS on liver fat as assessed using quantitative tomographic imaging in human adults. Where feasible, data were pooled, and meta-analyses conducted using random-effect model. Quality assessment was done according the Cochrane Collaboration's tool for assessing risk of bias. Twenty RCTs, involving 1171 overweight and obese adults, of which 36% were females, with or without comorbidities, were included. Only RCTs assessing omega-3 fatty acids (n = 4) and resveratrol (n = 4) qualified for meta-analysis. Results did neither favor omega-3 (effect size -1.17; weighted mean difference (WMD) (95% confidence interval (CI)) -3.62, 1.28; p < 0.001) nor resveratrol supplementation (0.18; 95% CI -1.08, 1.43; p = 0.27). The findings of the qualitatively summarized RCTs suggested that catechins (n = 1), Lactobacillus reuteri (n = 1), and carnitine (n = 1) may reduce liver fat. All other DS did not show any influence. The current evidence is scarce, of limited quality and does not support DS use to reduce liver fat. Further well-designed trials are warranted.
| S-EPMC7469018 | biostudies-literature
Project description:Type 2 diabetes mellitus (T2DM) increases the risk of cognitive decline and dementia. Disruptions in the cytochrome P450-soluble epoxide hydrolase (CYP450-sEH) pathway have been reported in T2DM, obesity and cognitive impairment. We examine linoleic acid (LA)-derived CYP450-sEH oxylipins and cognition in T2DM and explore potential differences between obese and nonobese individuals. The study included 51 obese and 57 nonobese participants (mean age 63.0 ± 9.9, 49% women) with T2DM. Executive function was assessed using the Stroop Color-Word Interference Test, FAS-Verbal Fluency Test, Digit Symbol Substitution Test, and Trails Making Test-Part B. Verbal memory was assessed using the California Verbal Learning Test, second Edition. Four LA-derived oxylipins were analyzed by ultra-high-pressure-LC/MS, and the 12,13-dihydroxyoctadecamonoenoic acid (12,13-DiHOME) considered the main species of interest. Models controlled for age, sex, BMI, glycosylated hemoglobin A1c, diabetes duration, depression, hypertension, and education. The sEH-derived 12,13-DiHOME was associated with poorer executive function scores (F1,98 = 7.513, P = 0.007). The CYP450-derived 12(13)-epoxyoctadecamonoenoic acid (12(13)-EpOME) was associated with poorer executive function and verbal memory scores (F1,98 = 7.222, P = 0.008 and F1,98 = 4.621, P = 0.034, respectively). There were interactions between obesity and the 12,13-DiHOME/12(13)-EpOME ratio (F1,97 = 5.498, P = 0.021) and between obesity and 9(10)-epoxyoctadecamonoenoic acid (9(10)-EpOME) concentrations (F1,97 = 4.126, P = 0.045), predicting executive function such that relationships were stronger in obese individuals. These findings suggest that the CYP450-sEH pathway as a potential therapeutic target for cognitive decline in T2DM. For some markers, relationships may be obesity dependent.
| S-EPMC10394387 | biostudies-literature
Project description:Prader-Willi Syndrome (PWS) is a human genetic condition that affects up to 1 in 10,000 live births. Affected infants present with hypotonia and developmental delay. Hyperphagia and increasing body weight follow unless drastic calorie restriction is initiated. Recently, our laboratory showed that one of the genes in the deleted locus causative for PWS, Snord116, maintains increased expression of hypothalamic Nhlh2, a basic helix-loop-helix transcription factor. We have previously also shown that obese mice with a deletion of Nhlh2 respond to a conjugated linoleic acid (CLA) diet with weight and fat loss. In this study, we investigated whether mice with a paternal deletion of Snord116 (Snord116m+/p-) would respond similarly. We found that while Snord116m+/p- mice and mice with a deletion of both Snord116 alleles were not significantly obese on a high-fat diet, they did lose body weight and fat on a high-fat/CLA diet, suggesting that the genotype did not interfere with CLA actions. There were no changes in food intake or metabolic rate, and only moderate differences in exercise performance. RNA-seq and microbiome analyses identified hypothalamic mRNAs, and differentially populated gut bacteria, that support future mechanistic analyses. CLA may be useful as a food additive to reduce obesity in humans with PWS.
| S-EPMC8880678 | biostudies-literature