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Background Non-alcoholic fatty liver disease (NAFLD) has been entitled as metabolic-dysfunction associated fatty liver disease (MAFLD). Therefore anthropometric indicators of adiposity may provide a non-invasive predictive and diagnostic tool for this disease. This study intended to validate and compare the MAFLD predictive and diagnostic capability of eight anthropometric indicators. Methods The study involved a population-based retrospective cross-sectional design. The Fangchenggang area male health and examination survey (FAMHES) was used to collect data of eight anthropometric indicators, involving body mass index (BMI), waist-to-height ratio (WHtR), waist-hip ratio (WHR), body adiposity index (BAI), cardiometabolic index (CMI), lipid accumulation product (LAP), visceral adiposity index (VAI), and abdominal volume index (AVI). Receiver operating characteristics (ROC) curves and the respective areas under the curves (AUCs) were utilized to compare the diagnostic capacity of each indicator for MAFLD and to determine the optimal cutoff points. Binary logistic regression analysis was applied to identify the odds ratios (OR) with 95% confidence intervals (95% CI) for all anthropometric indicators and MAFLD. The Spearman rank correlation coefficients of anthropometric indicators, sex hormones, and MAFLD were also calculated. Results All selected anthropometric indicators were significantly associated with MAFLD (P < 0.001), with an AUC above 0.79. LAP had the highest AUC [0.868 (95% CI, 0.853–0.883)], followed by WHtR [0.863 (95% CI, 0.848–0.879)] and AVI [0.859 (95% CI, 0.843–0.874)]. The cutoff values for WHtR, LAP and AVI were 0.49, 24.29, and 13.61, respectively. WHtR [OR 22.181 (95% CI, 16.216–30.340)] had the strongest association with MAFLD, regardless of potential confounders. Among all the anthropometric indicators, the strongest association was seen between LAP and sex hormones. Conclusion All anthropometric indicators were associated with MAFLD. WHtR was identified as the strongest predictor of MAFLD in young Chinese males, followed by LAP and AVI. The strongest association was found between LAP and sex hormones.

Background: Human urate transporter 1 (hURAT1) is the most pivotal therapeutic target for treating hyperuricemia. However, the molecular interactions between uric acid and URAT1 are still unknown due to lack of structural details. Methods: In the present study, several methods (homology modeling, sequence alignment, docking, and mutagenesis) were used to explain the atomistic mechanisms of uric acid transport of hURAT1. Results: Residues W357-F365 in the TMD7 and P484-R487 in the TMD11 present in the hURAT1 have unique roles in both binding to the uric acid and causing subsequent structural changes. These residues, located in the transport tunnel, were found to be related to the structural changes, as demonstrated by the reduced V max values and an unaltered expression of protein level. In addition, W357, G361, T363, F365, and R487 residues may confer high affinity for binding to uric acid. An outward-open homology model of hURAT1 revealed a crucial role for these two domains in the conformational changes of hURAT1. F241 and H245 in TMD5, and R477 and R487 in TMD11 may confer high affinity for uric acid, and as the docking analysis suggests, they may also enhance the affinity for the inhibitors. R477 relation to the structural changes was demonstrated by the V max values of the mutants and the contribution of positive charge to the uric acid selectivity. Conclusions: W357-F365 in TMD7, P484-R487 in TMD11, and residues F241, H245, and R477 were found to be critical for the translocation and recognition of uric acid.