AIM:Chronic exposure to elevated levels of free fatty acids (FFAs) in type 2 diabetes patients is toxic to pancreatic β-cells.Thioredoxin (Trx)-interacting protein (TXNIP), an endogenous Trx-inhibiting protein, is up-regulated by glucose and is a critical mediator of hyperglycemia-induced β-cell apoptosis in diabetes.However, the effects of FFAs on TXNIP are unknown.In this experiment we observed the effect of palmitate on TXNIP expression in cultured INS-1 islet cells and the pathways involved were analyzed meanwhile.METHODS:After the full basis of preliminary experiment of incubating INS-1 cells with palmitate at different concentrations for different time, INS-1 islet cells were cultured with 0.5 mmol/L palmitate for 24 h.TXNIP expression, cell apoptosis, and expression of transcription factors related to TXNIP transcriptional regulation were determined.RESULTS:Compared with control group, the expression of TXNIP at mRNA and protein levels in palmitate group was significantly up-regulated (P<0.01).Cleaved caspase-3/caspase-3 ratio was increased in palmitate group (P<0.05), and the apoptosis of the INS-1 cells was also significantly increased (P<0.01).Palmitate enhanced the phosphorylation of nuclear factor-κB (NF-κB) (P<0.01), and the NF-κB inhibitors, PDTC and SN50, both blocked the palmitate-induced up-regulation of TXNIP expression.CONCLUSION:Saturated fatty acid palmitate enhances the expression of TXNIP.The mechanism of palmitate-induced TXNIP expression may be associa-ted with the increase in NF-κB phosphorylation.

BACKGROUND: This study aimed to develop a comprehensive instrument for evaluating and ranking clinical practice guidelines, named Scientific, Transparent and Applicable Rankings tool (STAR), and test its reliability, validity, and usability. METHODS: This study set up a multidisciplinary working group including guideline methodologists, statisticians, journal editors, clinicians, and other experts. Scoping review, Delphi methods, and hierarchical analysis were used to develop the STAR tool. We evaluated the instrument's intrinsic and interrater reliability, content and criterion validity, and usability. RESULTS: STAR contained 39 items grouped into 11 domains. The mean intrinsic reliability of the domains, indicated by Cronbach's α coefficient, was 0.588 (95% confidence interval [CI]: 0.414, 0.762). Interrater reliability as assessed with Cohen's kappa coefficient was 0.774 (95% CI: 0.740, 0.807) for methodological evaluators and 0.618 (95% CI: 0.587, 0.648) for clinical evaluators. The overall content validity index was 0.905. Pearson's r correlation for criterion validity was 0.885 (95% CI: 0.804, 0.932). The mean usability score of the items was 4.6 and the median time spent to evaluate each guideline was 20 min. CONCLUSION The instrument performed well in terms of reliability, validity, and efficiency, and can be used for comprehensively evaluating and ranking guidelines.
Reproducibility of Results ; Surveys and Questionnaires ; Practice Guidelines as Topic ; Humans