Biomarkers of fatty acids and risk of type 2 diabetes: a systematic review and meta-analysis of prospective cohort studies

Association of circulating long-chain free fatty acids and incident diabetes risk among normoglycemic Chinese adults: a prospective nested case-control study

BACKGROUND

Long-chain free fatty acids (FFAs) are associated with risk of incident diabetes. However, a comprehensive assessment of the associations in normoglycemic populations is lacking.

OBJECTIVES

Our study aimed to comprehensively investigate the prospective associations and patterns of FFA profiles with diabetes risk among normoglycemic Chinese adults.

METHODS

This is a prospective nested case-control study from the China Cardiometabolic Disease and Cancer Cohort (4C) study. We quantitatively measured 53 serum FFAs using a targeted metabolomics approach in 1707 incident diabetes subjects and 1707 propensity score-matched normoglycemic controls. Conditional logistic regression models were employed to estimate odds ratios (ORs) for associations. Least Absolute Shrinkage and Selection Operator (LASSO) penalty regression and quantile g-computation (qg-comp) analyses were implemented to estimate the association between multi-FFA exposures and incident diabetes.

RESULTS

The majority of odd-chain FFAs exhibited an inverse association with incident diabetes, wherein the ORs per SD increment of all 7 saturated fatty acids (SFAs), monounsaturated fatty acid (MUFA) 15:1, and polyunsaturated fatty acid (PUFA) 25:2 were ranging from 0.79 to 0.88 (95% CIs ranging between 0.71 and 0.97). Even-chain FFAs comprised 99.3% of total FFAs and displayed heterogeneity with incident diabetes. SFAs with 18-26 carbon atoms are inversely linked to incident diabetes, with ORs ranging from 0.81 to 0.86 (95% CIs ranging between 0.73 and 0.94). MUFAs 26:1 (OR: 0.85; 95% CI: 0.76, 0.94), PUFAs 20:4 (OR: 0.84; 95% CI: 0.75, 0.94), and 24:2 (OR: 0.87; 95% CI: 0.78, 0.97) demonstrated significant associations. In multi-FFA exposure model, 24 FFAs were significantly associated with incident diabetes, most of which were consistent with univariate results. The mixture OR was 0.78 (95% CI: 0.61, 0.99; P = 0.04159). Differential correlation network analysis revealed pre-existing perturbations in intraclass and interclass FFA coregulation before diabetes onset.

CONCLUSIONS

These findings underscore the variations in diabetes risk associated with FFAs across chain length and unsaturation degree, highlighting the importance of recognizing FFA subtypes in the pathogenesis of diabetes.

TXNIP inhibition in the treatment of type 2 diabetes mellitus: design, synthesis, and biological evaluation of quinazoline derivatives

Thioredoxin interacting protein (TXNIP) is a potential drug target for type 2 diabetes mellitus (T2DM) treatment. A series of quinazoline derivatives were designed, synthesised, and evaluated to inhibit TXNIP expression and protect from palmitate (PA)-induced β cell injury. In vitro cell viability assay showed that compounds D-2 and C-1 could effectively protect β cell from PA-induced apoptosis, and subsequent results showed that these two compounds decreased TXNIP expression by accelerating its protein degradation. Mechanistically, compounds D-2 and C-1 reduced intracellular reactive oxygen species (ROS) production and modulated TXNIP-NLRP3 inflammasome signalling, and thus alleviating oxidative stress injury and inflammatory response under PA insult. Besides, these two compounds were predicted to possess better drug-likeness properties using SwissADME. The present study showed that compounds D-2 and C-1, especially compound D-2, were potent pancreatic β cell protective agents to inhibit TXNIP expression and might serve as promising lead candidates for the treatment of T2DM.

Associations between the inflammatory potential of diets with adherence to plant-based dietary patterns and the risk of new-onset cardiometabolic diseases in Chinese adults: findings from a nation-wide prospective cohort study

Aims: convincing evidence is still limited for the validation of associations between the inflammatory potential of diets, based on the dietary inflammatory index (DII), and cardiometabolic outcomes. We aimed to investigate the associations between the DII with adherence to plant-based dietary patterns and the risk of new-onset cardiometabolic diseases (CMDs), including stroke, type 2 diabetes mellitus (T2DM) and myocardial infarction (MI). Methods: adults (N = 14 652) from the China Health and Nutrition Survey (1997-2015) were included in the current analysis. Dietary intake data were collected using a combination of 3 day consecutive 24 h dietary recalls and the food weighing method. The DII was calculated with established and validated methods. CMDs were identified using validated self-reported questionnaires. The Cox proportional hazard regression model was used for statistical analysis. Results: during a mean follow-up of 10 years, a total of 404 new-onset stroke, 1051 new-onset T2DM and 280 new-onset MI cases were identified. Lower PDI, hPDI, ERD, WISH and PHDI scores and higher uPDI scores were associated with higher DII scores (all P-trend < 0. 0001). A pro-inflammatory diet, as reflected by relatively higher DII scores, was positively associated with an increased risk of stroke (Q5 vs. Q1: HR = 1.90; 95% CI: 1.26-2.88; P-trend = 0.0006), T2DM (Q5 vs. Q1: HR = 2.08; 95% CI: 1.61-2.69; P-trend < 0.0001) and MI (Q5 vs. Q1: HR = 1.70; 95% CI: 1.04-2.76; P-trend = 0.0114) in the entire cohort. Sex and BMI significantly modified the association between the DII and the risk of T2DM, and sex significantly modified the association between the DII and the risk of MI. Conclusions: lower adherence to healthy and sustainable plant-based dietary patterns and higher adherence to unhealthy plant-based dietary patterns were associated with higher DII scores. With the use of the DII, we reported long-term positive associations between a pro-inflammatory diet and an increased risk of new-onset stroke, T2DM and MI in Chinese adults who were free from CMDs and cancer at the baseline. These findings provided evidence for the validation of associations between the DII and cardiometabolic health, and contributed to the current literature suggesting careful evaluations of whether the DII should be incorporated into dietary guidelines and utilized as an effective tool for improving the diet quality and CMD prevention in the Chinese population.

Association between Omega-3 Index and Hyperglycemia Depending on Body Mass Index among Adults in the United States

There is inconsistency regarding the association between long-chain n-3 polyunsaturated fatty acids such as eicosapentaenoic acid (EPA; 20:5n3) and docosahexaenoic acid (DHA; 22:6n3) and the risk of type 2 diabetes. The present study aimed to investigate the association between the Omega-3 Index (erythrocyte EPA + DHA) and glycemic status as a function of body mass index (BMI). Cross-sectional data from routine clinical laboratory testing with a total of 100,572 people aged over 18 years and BMI ≥ 18.5 kg/m² were included. Of the patients, 10% were hyperglycemic (fasting plasma glucose levels ≥ 126 mg/dL) and 24.7% were of normal weight, 35.0% were overweight, and 40.3% were obese. Odds ratios (ORs) of being hyperglycemic were inversely associated with the Omega-3 Index, but weakened as BMI increased. Thus, ORs (95% CI) comparing quintile 5 with quintile 1 were 0.54 (0.44-0.66) in the normal weight group, 0.70 (0.61-0.79) in the overweight group, and 0.74 (0.67-0.81) in the obese group. Similar patterns were seen for EPA and DHA separately. The present study suggested that a low Omega-3 Index is associated with a greater risk of disordered glucose metabolism and this is independent of BMI.