miR-29a-3p has been shown to be associated with cardiovascular diseases; however, the effect of miR-29a-3p on endothelial dysfunction is unclear. This study aimed to reveal the effects and mechanisms of miR-29a-3p on endothelial dysfunction. The levels of vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), and E-selectin were determined by real-time PCR and immunofluorescence staining to reveal the degree of tumor necrosis factor alpha (TNFα)-induced endothelial dysfunction. A luciferase activity assay and cell transfection with a miR-29a-3p mimic or an inhibitor were used to reveal the underlying mechanisms of miR-29a-3p action. Furthermore, the effects of miR-29a-3p on endothelial dysfunction were assessed in C57BL/6 mice injected with TNFα and/or a miR-29a-3p agomir. The results showed that the expression of TNFα-induced adhesion molecules in vascular endothelial cells (EA.hy926 cells, human aortic endothelial cells [HAECs], and primary human umbilical vein endothelial cells [pHUVECs]) and smooth muscle cells (human umbilical vein smooth muscle cells [HUVSMCs]) was significantly decreased following transfection with miR-29a-3p. This effect was reversed by cotransfection with a miR-29a-3p inhibitor. As a key target of miR-29a-3p, tumor necrosis factor receptor 1 mediated the effect of miR-29a-3p. Moreover, miR-29a-3p decreased the plasma levels of TNFα-induced VCAM-1 (32.62%), ICAM-1 (38.22%), and E-selectin (39.32%) in vivo. These data indicate that miR-29a-3p plays a protective role in TNFα-induced endothelial dysfunction, suggesting that miR-29a-3p is a novel target for the prevention and treatment of atherosclerosis.

Aims/hypothesis Alcohol consumption levels frequently fluctuate over the life course, but studies examining the association between alcohol consumption trajectories and type 2 diabetes are limited. This study aims to investigate the association of alcohol consumption trajectories with the risk of type 2 diabetes and its related factors. Methods Weighted longitudinal data were obtained for 12,186 adults who completed a questionnaire about alcohol consumption and diabetes status as part of the China Health and Nutrition Survey (1993-2011). Participants were designated into subgroups based on alcohol consumption trajectory, and subgroup analyses included 5436 individuals who were tested for specified diabetes-related factors. Light alcohol consumption was defined as fewer than seven standard drinks per week; moderate as 7-21 drinks per week; and heavy as more than 21 drinks per week. Latent class trajectory modelling was used to identify different alcohol consumption trajectories by sex. Multivariate Cox regression models and general linear regression models were used to assess association of trajectories with type 2 diabetes and its related factors. Results Compared with stable abstainers (individuals who never drank alcohol), two trajectories in men showing reduction to moderate or light levels after heavy alcohol consumption during early adulthood were significantly associated with increased risk of type 2 diabetes (HR 1.66 [95% CI 1.18, 2.33]; HR 1.93 [95% CI 1.01, 3.70]), while no significant association between trajectories and risk of type 2 diabetes was observed in women (p for trend = 0.404). Triacylglycerol, HDL-cholesterol (HDL-C), uric acid and high sensitivity C-reactive protein were significantly higher in these two trajectories than other trajectories in men (all p < 0.05), while only HDL-C showed significant increasing trends in women. Trajectories showing light-stable, or increase to moderate, levels were not associated with reduced risk of type 2 diabetes. Conclusions This study indicated that heavy alcohol consumption in early adulthood is significantly associated with increased risk of type 2 diabetes and higher levels of its biomarkers throughout adulthood in men. Gradually reducing alcohol consumption to moderate levels may not make a difference, which demonstrates the importance of alcohol intervention strategies in early adulthood. Although association between alcohol consumption and increased HDL-C levels has been observed, the results of this study did not support the hypothesis regarding the protective effect of moderate alcohol consumption on risk of type 2 diabetes in the Asian population. Data availability Data from China Health and Nutrition Survey was used in this study, which can be downloaded at www.cpc. unc.edu/projects/china.

Background There is insufficient evidence for the ability of vitamin K2 to improve type 2 diabetes mellitus symptoms by regulating gut microbial composition. Herein, we aimed to demonstrate the key role of the gut microbiota in the improvement of impaired glycemic homeostasis and insulin sensitivity by vitamin K2 intervention. Methods We first performed a 6-month RCT on 60 T2DM participants with or without MK-7 (a natural form of vitamin K2) intervention. In addition, we conducted a transplantation of the MK-7-regulated microbiota in diet-induced obesity mice for 4 weeks. 16S rRNA sequencing, fecal metabolomics, and transcriptomics in both study phases were used to clarify the potential mechanism. Results After MK-7 intervention, we observed notable 13.4%, 28.3%, and 7.4% reductions in fasting serum glucose (P = 0.048), insulin (P = 0.005), and HbA1c levels (P = 0.019) in type 2 diabetes participants and significant glucose tolerance improvement in diet-induced obesity mice (P = 0.005). Moreover, increased concentrations of secondary bile acids (lithocholic and taurodeoxycholic acid) and short-chain fatty acids (acetic acid, butyric acid, and valeric acid) were found in human and mouse feces accompanied by an increased abundance of the genera that are responsible for the biosynthesis of these metabolites. Finally, we found that 4 weeks of fecal microbiota transplantation significantly improved glucose tolerance in diet-induced obesity mice by activating colon bile acid receptors, improving host immune-inflammatory responses, and increasing circulating GLP-1 concentrations. Conclusions Our gut-derived findings provide evidence for a regulatory role of vitamin K2 on glycemic homeostasis, which may further facilitate the clinical implementation of vitamin K2 intervention for diabetes management. Trial registration The study was registered at https://www.chictr.org.cn (ChiCTR1800019663).

BackgroundTryptophan and its metabolites have been found related to various cancers, but the direction of this relationship is still unclear. The purpose of this study is to explore the causal associations of tryptophan and kynurenine with multiple cancers based on the bidirectional Mendelian randomization analysis.MethodsThe data of a genome-wide association study meta-analysis on 7,824 individuals was used to explore the genetic variants strongly associated with tryptophan and kynurenine. Genetic instruments of four specific cancers were obtained from available summary-level data of 323,590 European participants. Bidirectional Mendelian randomization analysis was conducted to examine possible causality. Sensitivity analysis was performed to test heterogeneity and horizontal pleiotropy. COX regression analysis was conducted to explore associations between dietary tryptophan and cancer mortality in NHANES 1988-1994.ResultsNo evidence of any causal association of tryptophan and kynurenine with the risk of four specific cancers was shown, except for weak correlations were suggested between lung or prostate cancer and kynurenine. Multiple sensitivity analyses generated similar results. Our findings from COX regression analysis were consistent with the above results.ConclusionsOur study did not find any causal relationship between tryptophan and kynurenine and multiple cancers. The associations still need further research.

The aim of the untargeted metabolomics study is to obtain a global metabolome coverage from biological samples. Therefore, a comprehensive and systematic protocol for tissue metabolite extraction is highly desirable. In this study, we evaluated a comprehensive liver pretreatment strategy based on ultra-highperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry to obtain more metabolites using four different protocols.These protocols included (A) methanol protein precipitation, (B) two-step extraction of dichloromethane-methanol followed by methanol-water, (C) two-step extraction of methyl tert-butyl ether-methanol followed by methanol-water, and (D) two-step extraction of isopropanol-methanol followed by methanol-water. Our results showed that protocol D was superior to the others due to more extracted features, annotated metabolites, and better reproducibility. And then, the stability and extraction sequence of protocol D were evaluated. The results showed that extraction with isopropanol-methanol followed by methanol-water was the optimum preparation sequence, which offered higher extraction efficiency, satisfactory repeatability, and acceptable stability. Furthermore, the optimal protocol was successfully applied by liver samples of rats after high-fat intervention. In summary, our protocol enabled a comprehensive and systematic evaluation of liver pretreatment to obtain more medium-polar and nonpolar metabolites and was suitable for high-throughput metabolomics analysis.