We have repeatedly shown in short-term feeding trials that a high intake of dietary n–6 PUFAs, i.e. linoleic acid, prevents liver fat accumulation compared with saturated fat. However, ...population-based data is lacking and the mechanisms behind such effects are unclear.
To investigate associations between serum cholesteryl ester (CE) fatty acids and liver fat, basal fat oxidation respiratory quotient (RQ), and resting energy expenditure (REE). We hypothesized that PUFA in particular is inversely associated with liver fat and that such a relation is partly explained by a PUFA-induced increase in basal fat oxidation or REE.
Cross-sectional analyses using linear regression models in a population-based cohort with data on serum CE fatty acid composition and liver fat (n = 308).
Linoleic acid (18:2n–6) (β = −0.03, 95% CI: −0.06, −0.001) and Δ5 desaturase index were inversely associated, whereas, γ-linolenic acid (18:3n–6) (β = 0.59, 95% CI: 0.28, 0.90), dihomo-γ-linolenic acid (20:3n–6) (β = 1.20, 95% CI: 0.65, 1.75), arachidonic acid (20:4n–6) (β = 0.08, 95% CI: 0.002, 0.16), palmitoleic acid (16:1n–7) (β = 0.37, 95% CI: 0.04, 0.70), Δ6 desaturase, and stearoyl CoA desaturase-1 (SCD-1) index were directly associated with liver fat after adjustment for confounders. Several serum CE fatty acids were correlated with both liver fat and REE, but only the association between DHA (22:6n–3) and liver fat was clearly attenuated after adjustment for REE (from β = −0.63 95% CI: −1.24, −0.02 to β = −0.34, 95% CI: −0.95, 0.27). Palmitoleic acid and SCD-1 were weakly inversely correlated with RQ but could not explain a lower liver fat content.
Several serum CE fatty acids are associated with liver fat, among them linoleic acid. Although we identified novel associations between individual fatty acids and RQ and REE, our findings imply that PUFAs might prevent liver fat accumulation through mechanisms other than enhanced whole-body energy metabolism.
•No link between insomnia symptoms and insulin sensitivity in elderly men.•No link between insomnia symptoms and circulating levels of adiponectin.•No link between insomnia symptoms and circulating ...levels of free fatty acids.•Insomnia symptoms may have a minimal effect on insulin sensitivity in elderly men.
Insomnia-related sleep disruptions, such as short and disturbed sleep, have been tied to systemic insulin resistance in young adult populations. We therefore sought to confirm these findings in a cohort of elderly men. To this aim, we utilized variables from 980 men who participated in the investigation at age 70 of the Uppsala Longitudinal Study of Adult Men. Self‐reported insomnia symptoms were assessed by questions about difficulty initiating sleep, early final awakening, and regular use of hypnotics. All participants also underwent the gold-standard hyperinsulinemic-euglycemic clamp technique to assess the insulin sensitivity index (M/I). Finally, fasting blood was collected to measure free fatty acids (FFAs) and adiponectin. Differences in blood parameters between men with and those without insomnia were determined by ANCOVA, and were adjusted for lifestyle and cardio-metabolic risk factors. Our analysis yielded no differences in M/I, FFAs, and adiponectin between men with and those without insomnia symptoms. Analyses in non-diabetic and diabetic subsamples confirmed these negative findings. Our cross-sectional results therefore suggest that insomnia symptoms may have a minimal effect, if any, on measures of insulin sensitivity in elderly men. Given the observational design of our study, future studies are needed to determine whether experimental sleep manipulations influence systemic insulin sensitivity in elderly humans, as has previously been shown in young adult populations.
Abdominal obesity is a key contributor of metabolic disease. Recent trials suggest that dietary fat quality affects abdominal fat content, where palmitic acid and linoleic acid influence abdominal ...obesity differently, while effects of n-3 polyunsaturated fatty acids are less studied. Also, fatty acid desaturation may be altered in abdominal obesity. We aimed to investigate cross-sectional associations of serum fatty acids and desaturases with abdominal obesity prevalence in a population-based cohort study. Serum cholesteryl ester fatty acids composition was measured by gas chromatography in 60-year old men (n = 1883) and women (n = 2015). Cross-sectional associations of fatty acids with abdominal obesity prevalence and anthropometric measures (e.g., sagittal abdominal diameter) were evaluated in multivariable-adjusted logistic and linear regression models, respectively. Similar models were employed to investigate relations between desaturase activities (estimated by fatty acid ratios) and abdominal obesity. In logistic regression analyses, palmitic acid, stearoyl-CoA-desaturase and Δ6-desaturase indices were associated with abdominal obesity; multivariable-adjusted odds ratios (95% confidence intervals) for highest versus lowest quartiles were 1.45 (1.19-1.76), 4.06 (3.27-5.05), and 3.07 (2.51-3.75), respectively. Linoleic acid, α-linolenic acid, docohexaenoic acid, and Δ5-desaturase were inversely associated with abdominal obesity; multivariable-adjusted odds ratios (95% confidence intervals): 0.39 (0.32-0.48), 0.74 (0.61-0.89), 0.76 (0.62-0.93), and 0.40 (0.33-0.49), respectively. Eicosapentaenoic acid was not associated with abdominal obesity. Similar results were obtained from linear regression models evaluating associations with different anthropometric measures. Sex-specific and linear associations were mainly observed for n3-polyunsaturated fatty acids, while associations of the other exposures were generally non-linear and similar across sexes. In accordance with findings from short-term trials, abdominal obesity was more common among individuals with relatively high proportions of palmitic acid, whilst the contrary was true for linoleic acid. Further trials should examine the potential role of linoleic acid and its main dietary source, vegetable oils, in abdominal obesity prevention.
Adherence to a Mediterranean diet may link to a better preserved kidney function in the community as well as a favorable cardiometabolic profile and reduced mortality risk in individuals with ...manifest CKD.
Dietary habits were determined by 7-day dietary records in a population-based cohort of 1110 Swedish men (age 70 years) from 1991 to 1995, 506 of whom were considered to have CKD because of a GFR<60 ml/min per 1.73 m(2). A Mediterranean Diet Score was calculated, and participants were categorized as having low, medium, or high adherence. Adequate dietary reporters were identified with Goldberg cutoffs (n=597). Deaths were registered during a median follow-up of 9.9 years.
Compared with low adherents, medium and high adherents were 23% and 42% less likely to have CKD, respectively (adjusted odds ratio 95% confidence interval=0.77 0.57 to 1.05 and 0.58 0.38 to 0.87, respectively, P for trend=0.04). Among those individuals with CKD, phosphate intake and net endogenous acid production were progressively lower across increasing adherence groups. No differences were observed regarding other cardiometabolic risk factors across adherence groups. As many as 168 (33%) CKD individuals died during follow-up. Compared with low adherents, proportional hazards regression associated medium and high adherents to a 25% and 23% lower mortality risk, respectively (adjusted hazard ratio 95% confidence interval=0.75 0.52 to 1.06 and 0.77 0.44 to 1.36, respectively, P for trend=0.10). Sensitivity analyses showed significant and stronger associations when only adequate dietary reporters were considered.
Adherence to a Mediterranean dietary pattern is associated with lower likelihood of CKD in elderly men. A greater adherence to this diet independently predicted survival in those patients with manifest CKD. Clinical trials are warranted to test the hypothesis that following such a diet could improve outcomes (independent of other healthy lifestyles) in CKD patients.
The quality of dietary fat in relation to cardiovascular disease forms the basis of the diet-heart hypothesis. Current recommendations on dietary fat now emphasise quality rather than quantity. The ...focus of this review is to summarise the results from prospective cohort studies on dietary fat and cardiovascular disease outcomes. Relatively few prospective cohort studies have found an association between dietary fat quality and cardiovascular disease, partly because of limitations in estimating dietary intake. Saturated and
trans fatty acids have increased cardiovascular risk in several studies. Both n−6 and n−3 polyunsaturated fatty acids have been associated with lower cardiovascular risk. Within the n−6 series, linoleic acid seems to decrease cardiovascular risk. Within the n−3 series the long-chain fatty acids (eicosapentaenoic and docosahexaenoic acids) are associated with decreased risk for especially fatal coronary outcomes, whereas the role of α-linolenic acid is less clear. Dietary fat quality also influences the activity of enzymes involved in the desaturation of fatty acids in the body. Serum desaturase indices have been consistently associated with adverse cardiovascular outcomes. Data from metabolic and clinical studies reinforce findings from observational studies supporting recommendations to replace saturated and
trans fat with unsaturated fat in the prevention of cardiovascular disease.
Whole grain rye products have been shown to increase satiety and elicit lower postprandial insulin response without a corresponding change in glucose response compared with soft refined wheat bread. ...The underlying mechanisms for these effects have not been fully determined The primary aim of the study was to investigate if whole grain rye crisp bread compared to refined wheat crisp bread, elected beneficial effects on appetite and postprandial insulin response, similarly as for other rye products.
In a randomized cross-over trial, 23 healthy volunteers, aged 27-70 years, BMI 18-31.4 kg/m2, were served a standardized breakfast with unfermented whole grain rye crisp bread (uRCB), fermented whole grain rye crisp bread (RCB) or refined wheat crisp bread (WCB), Appetite was measured using a visual analogue scale (VAS) until 4 h after breakfast. Postprandial glucose and insulin were measured at 0-230 min. Breads were chemically characterized including macronutrients, energy, dietary fiber components, and amino acid composition, and microstructure was characterized with light microscopy.
Reported fullness was 16% higher (P<0.001), and hunger 11% and 12% lower (P<0.05) after ingestion of uRCB and RCB, respectively, compared with WCB. Postprandial glucose response did not differ significantly between treatments. Postprandial insulin was 10% lower (P<0.007) between 0-120 min but not significantly lower between 0-230 min for RCB compared with WCB. uRCB induced 13% (P<0.002) and 17% (P<0.001) lower postprandial insulin response between 0-230 min compared with RCB and WCB respectively.
Whole grain rye crisp bread induces higher satiety and lower insulin response compared with refined wheat crisp bread. Microstructural characteristics, dietary fiber content and composition are probable contributors to the increased satiety after ingestion of rye crisp breads. Higher insulin secretion after ingestion of RCB and WCB compared with uRCB may be due to differences in fiber content and composition, and higher availability of insulinogenic branched chain amino acids.
ClinicalTrials.gov NCT02011217.
Abstract Objectives To find out if the presence of the metabolic syndrome increases the risk of subsequent total and cardiovascular mortality, taking into account established risk factors for ...cardiovascular disease. Design Prospective cohort study. Setting General population. Participants A community based sample of 2322 men followed since 1970 for a maximum of 32.7 years, investigated at ages 50 and 70. Main outcome measures The relations of the metabolic syndrome defined by the national cholesterol education programme (NCEP) of the US National Heart, Lung, and Blood Institute or criteria of the World Health Organization (WHO) to subsequent total and cardiovascular mortality. Results When adding the metabolic syndrome to models with established risk factors for cardiovascular disease (smoking, diabetes, hypertension, and serum cholesterol) at age 50, presence of the metabolic syndrome as defined in the NCEP significantly predicted total and cardiovascular mortality (Cox proportional hazard ratios 1.36, 95% confidence interval 1.17 to 1.58; and 1.59, 1.29 to 1.95, respectively). The metabolic syndrome added prognostic information to that of the established risk factors for cardiovascular disease (likelihood ratio tests, P < 0.0001 for both outcomes). Similar results were obtained in a subsample without diabetes or manifest cardiovascular disease. Conclusions In a large, community based sample of middle aged men, the presence of the metabolic syndrome according to the definition of the NCEP gave long term prognostic information regarding total and cardiovascular mortality if the status of established risk factors for cardiovascular disease was known. If confirmed this may indicate clinical value in diagnosing the metabolic syndrome.
Bisphenol A (BPA) is an endocrine disruptor and also a suggested obesogen and metabolism-disrupting chemical. Accumulating data indicates that the fatty acid (FA) profile and their ratios in plasma ...and other metabolic tissues are associated with metabolic disorders. Stearoyl-CoA desaturase 1 (SCD-1) is a key regulator of lipid metabolism and its activity can be estimated by dividing the FA product by its precursor measured in blood or other tissues.
The primary aim of this study was to investigate the effect of low-dose developmental BPA exposure on tissue-specific FA composition including estimated SCD-1 activity, studied in 5- and 52-week (wk)-old Fischer 344 (F344) rat offspring.
Pregnant F344 rats were exposed to BPA via their drinking water corresponding to 0: CTRL, 0.5: BPA0.5, or 50 µg/kg BW/day: BPA50, from gestational day 3.5 until postnatal day 22.
BPA0.5 increased SCD-16 (estimated as the 16:1n-7/16:0 ratio) and SCD-18 (estimated as the 18:1n-9/18:0 ratio) indices in inguinal white adipose tissue triglycerides (iWAT-TG) and in plasma cholesterol esters (PL-CE), respectively, in 5-wk-old male offspring. In addition, BPA0.5 altered the FA composition in male offspring, e.g. by decreasing levels of the essential polyunsaturated FA linoleic acid (18:2n-6) in iWAT-and liver-TG. No differences were observed regarding the studied FAs in 52-wk-old offspring, although a slightly increased BW was observed in 52-wk-old female offspring.
Low-dose developmental BPA exposure increased SCD-16 in iWAT-TG and SCD-18 in PL-CE of male offspring, which may reflect higher SCD-1 activity in these tissues. Altered desaturation activity and signs of altered FA composition are novel findings that may indicate insulin resistance in the rat offspring. These aforementioned results, together with the observed increased BW, adds to previously published data demonstrating that BPA can act as a metabolism disrupting chemical.
•Low-dose developmental exposure to BPA alters fatty acid composition in rats.•Increased fatty acid markers of SCD-1 activity in male offspring.•Decreased levels of linoleic acid, an essential fatty acid, in male offspring.•Increased body weight was found in female offspring.•The observed altered fatty acid composition may reflect insulin resistance.
Background: Diabetic kidney disease (DKD) is a leading risk factor for end-stage renal disease and is one of the most important risk factors for cardiovascular disease in patients with diabetes. It ...is possible that novel markers portraying the pathophysiological underpinning processes may be useful.
Aim: To investigate the associations between 80 circulating proteins, measured by a proximity extension assay, and prevalent DKD and major adverse cardiovascular events (MACE) in type 2 diabetes.
Methods: We randomly divided individuals with type 2 diabetes from three cohorts into a two-thirds discovery and one-third replication set (total n = 813, of whom 231 had DKD defined by estimated glomerular filtration rate <60 mg/mL/1.73 m
2
and/or urinary albumin-creatinine ratio ≥3 g/mol). Proteins associated with DKD were also assessed as predictors for incident major adverse cardiovascular events (MACE) in persons with DKD at baseline.
Results: Four proteins were positively associated with DKD in models adjusted for age, sex, cardiovascular risk factors, glucose control, and diabetes medication: kidney injury molecule-1 (KIM-1, odds ratio OR per standard deviation increment, 1.65, 95% confidence interval CI 1.27-2.14); growth differentiation factor 15 (GDF-15, OR 1.40, 95% CI 1.16-1.69); myoglobin (OR 1.57, 95% CI 1.30-1.91), and matrix metalloproteinase 10 (MMP-10, OR 1.43, 95% CI 1.17-1.74). In patients with DKD, GDF-15 was significantly associated with increased risk of MACE after adjustments for baseline age, sex, microalbuminuria, and kidney function and (59 MACE events during 7 years follow-up, hazard ratio per standard deviation increase 1.43 95% CI 1.03-1.98) but not after further adjustments for cardiovascular risk factors.
Conclusion: Our proteomics approach confirms and extends previous associations of higher circulating levels of GDF-15 with both micro- and macrovascular disease in patients with type 2 diabetes. Our data encourage additional studies evaluating the clinical utility of our findings.
Fatty acid composition of serum lipids and adipose tissue triacylglycerols (AT-TAG) partly reflect dietary fatty acid intake. The fatty acid composition is, besides the diet, also influenced by ...desaturating enzymes that can be estimated using product-to-precursor fatty acid ratios. The interrelationships between desaturase indices derived from different serum lipid fractions and adipose tissue are unclear, as well as their associations with obesity and insulin resistance. We aimed to investigate cross-sectional correlations between desaturase indices as measured in serum lipid fractions (phospholipids; PL and free fatty acids; FFA) and in adipose tissue (AT-TAG). In a population-based sample of 301 healthy 60-year-old men various desaturase indices were assessed: stearoyl-CoA-desaturase (16:1n-7/16:0; SCD-16 and 18:1n-9/18:0; SCD-18, respectively), delta-6-desaturase (20:3n-6/18:2n-6; D6D) and delta-5-desaturase (20:4n-6/20:3n-6; D5D). Correlations with BMI and insulin resistance (HOMA-IR) were also examined. SCD-16 and D5D were significantly correlated between fractions and tissues (all r > 0.30), whereas SCD-18 and D6D were not. Desaturase indices in serum FFA and AT-TAG were significantly correlated; SCD-16 (r = 0.63), SCD-18 (r = 0.37), and D5D (r = 0.43). In phospholipids, SCD-16 was positively correlated to BMI (r = 0.15), while D5D negatively to both BMI (r = -0.30) and HOMA-IR (r = -0.31), all p < 0.01. D6D in both phospholipids and AT-TAG was positively correlated to HOMA-IR and BMI (all p < 0.01). In conclusion, SCD-1 and D5D activity indices showed overall strong correlations between lipid pools. SCD-1 activity index in adipose tissue is best reflected by 16:1/16:0-ratio in serum FFA, but associations with obesity and insulin resistance differ between these pools. D5D in PL was inversely related to obesity and insulin resistance, whereas D6D index showed positive associations.