High incidence of type 2 diabetes in a population with normal range body mass index and individual prediction nomogram in Vietnam.

AIMS: The study aimed at determining 5-year incidence and prediction nomogram for new-onset type 2 diabetes (T2D) in a middle-aged population in Vietnam. METHODS: A population-based prospective study was designed to collect socio-economic, anthropometric, lifestyle and clinical data. Five-year T2D incidence was estimated and adjusted for age and sex. Hazard ratio (HR) for T2D was investigated using discrete-time proportional hazards model. T2D prediction model entering the most significant risk factors was developed using the multivariable logistic-regression algorithm. The corresponding prediction nomogram was constructed and checked for discrimination, calibration and clinical usefulness. RESULTS: The age- and sex-adjusted incidence was 21.0 cases (95% CI: 12.2-40.0) per 1000 person-years in people with mean BMI of 22.2 (95% CI: 21.9-22.7 kg/m2 ). The HRs (95% CI) for T2D were 1.14 (1.05-1.23) per 10 mmHg systolic blood pressure, 1.05 (1.03-1.08) per 1 cm waist circumference, 1.40 (1.13-1.73) per 1 mmol/L fasting blood glucose, 1.77 (1.15-2.71) per sleeping time (<6 h/day vs 6-7 h/day) and 2.12 (1.25-3.61) per residence (urban vs rural). The prediction nomogram for new-onset T2D had a good discrimination (area under curve: 0.711, 95% CI: 0.666-0.755) and fit calibration (mean absolute error: 0.009). For the predicted probability thresholds between 0.03 and 0.36, the nomogram showed a positive net benefit, without increasing the number of false positives. CONCLUSION: This study highlighted an alarmingly high incidence of T2D in a middle-aged population with a normal range BMI in Vietnam. The individual prediction nomogram with decision curve analysis for new-onset T2D would be valuable for early detection, intervention and treatment of the condition.

Dammarane triterpenes and phytosterols from Dysoxylum tpongense Pierre and their anti-inflammatory activity against liver X receptors and NF-κB activation.

Dysoxylum tpongense Pierre (local name 'Huynh Dan Bap') belonging to family Meliaceae, is a tree (3-10 m height), distributed in the mountainous areas (ca. 1000 m a.s.l.) in North Vietnam. From the dichloromethane fraction of the methanol extract of the leaves and stems of this plant, six dammarane triterpenes, one furanoid diterpene together with three sterols were isolated. Evaluation of biological activities of isolated compounds showed that cabraleahydroxylactone (5), cabraleahydroxylactone 3-acetate (6), and stigmast-4-en-3-one (10) possessed an anti-inflammatory effect against Liver X receptor (LXR) activation in HepG2 cell line model with IC50 values of 20.29 ± 3.69, 24.32 ± 2.99, and 7.09 ± 0.97 (µM), respectively. While three other triterpenoid compounds aglinin C 3- acetate (1), aglinin C (2), and 24-epi-cabraleadiol (4) presented the most significant inhibitory effect against TNF-α induced NF-κB activation in HepG2 cell line in a dose-dependent manner with IC50 values of 12.45 ± 2.37, 23.32 ± 3.25, and 13.95 ± 1.57 µM, respectively. As stigmast-4-en-3-one (10), with structure closely similar to cholesterol, acted selectively on LXRs but not on NF-kB activation pathway, this suggests that stigmast-4-en-3-one (10) can be potentially applied as an agonist on LXR signaling pathway. Pathways LXRs-NF-κB-iNOS expression have a close relationship and play a crucial role in proceeding metabolic abnormalities like atherosclerosis, obesity, inflammation, etc. Thus, the findings showed that dammarane-type triterpenoids from D. tpongense are worthy of further investigation for potential LXR agonists and potent anti-atherogenic agents against atherosclerotic lesion progression.