Melatonin safeguards against fatty liver by antagonizing TRAFs‐mediated ASK1 deubiquitination and stabilization in a β‐arrestin‐1 dependent manner

Melatonin has been previously shown to prevent nonalcoholic fatty liver disease (NAFLD), yet the underlying mechanisms are poorly understood. Here, we identified a previously unknown regulatory action of melatonin on apoptosis signal‐regulating kinase 1 (ASK1) signaling pathway in the pathogenesis and development of NAFLD. Although melatonin administration did not alter food intake, it significantly alleviated fatty liver phenotypes, including the body weight gain, insulin resistance, hepatic lipid accumulation, steatohepatitis, and fibrosis in a high‐fat diet (HFD)‐induced NAFLD mouse model (in vivo). The protection of melatonin against NAFLD was not affected by inactivation of Kupffer cell in this model. In NAFLD mice liver, ASK1 signal cascade was substantially activated, evidence by the enhancement of total ASK1, phospho‐ASK1, phospho‐MKK3/6, phospho‐p38, phospho‐MKK4/7, and phospho‐JNK. Melatonin treatment significantly suppressed the ASK1 upregulation and the phosphorylation of ASK1, MKK3/6, MKK4/7, p38, and JNK. Mechanistically, we found that lipid stress triggered the interaction between ASK1 and TNF receptor‐associated factors (TRAFs), including TRAF1, TRAF2, and TRAF6, which resulted in ASK1 deubiquitination and thereby increased ASK1 protein stability. Melatonin did not alter ASK1 mRNA level; however, it activated a scaffold protein β‐arrestin‐1 and enabled it to bind to ASK1, which antagonized the TRAFs‐mediated ASK1 deubiquitination, and thus reduced ASK1 protein stability. Consistent with these findings, knockout of β‐arrestin‐1 in mice partly abolished the protection of melatonin against NAFLD. Taken together, our results for the first time demonstrate that melatonin safeguards against NAFLD by eliminating ASK1 activation via inhibiting TRAFs‐mediated ASK1 deubiquitination and stabilization in a β‐arrestin‐1 dependent manner.     

农村老年人老化期望现状及影响因素研究

目的 了解农村老年人的老化期望现状，分析其影响因素，为针对干预提供参考。 方法 采用一般资料调查表、UCLA孤独感量表简化版、老化期望量表、简版自我感知老化量表对199名农村老年人进行问卷调查。 结果 老化期望总分为32.72±9.18，孤独感得分为15.11±3.82，自我感知老化得分为52.75±2.76；多元线性回归分析显示，性别、婚姻状况、患慢性病种数、独居、孤独感、自我感知老化及经济来源是农村老年人老化期望的影响因素（调整R2=0.612，均P＜0.05）。 结论 农村老年人的老化期望水平较低，女性、孤独、无配偶、患慢性病较多、老化态度消极及低收入人群是关注的重点。     

Evidence of association between single-nucleotide polymorphisms in lipid metabolism-related genes and type 2 diabetes mellitus in a Chinese population

Background: Type 2 diabetes mellitus (T2DM) is a complex chronic metabolic disorder triggered by insulin resistance in peripheral tissues. Evidence has shown that lipid metabolism and related genetic factors lead to insulin resistance. Hence, it is meaningful to investigate the association between single-nucleotide polymorphisms (SNPs) in lipid metabolism-related genes and T2DM.Methods: A total of 1,194 subjects with T2DM and 1,274 Non-diabetic subjects (NDM) were enrolled. Five SNPs in three genes (rs864745 in JAZF1, rs35767 in IGF1, and rs4376068, rs4402960, and rs6769511 in IGF2BP2) that contribute to insulin resistance involving lipid metabolism were genotyped using the MassArray method in a Chinese population.Results: The allele and genotypes of rs6769511 in IGF2BP2 were associated with T2DM (P=0.009 and P=0.002, respectively). In inheritance model analysis, compared with the T/T-C/T genotype, the C/C genotype of rs6769511 in IGF2BP2 was a risk factor for the development of T2DM (P<0.001, odds ratio [OR] =1.76; 95% confidence interval [CI]: 1.29-2.42). Haplotype analysis revealed associations of the rs4376068-rs4402960-rs6769511 haplotypes in IGF2BP2 with the development of T2DM (P=0.015). Additionally, rs4376068C-rs4402960T-rs6769511C was a risk haplotype for T2DM (OR=1.179; 95% CI: 1.033-1.346).Conclusion: The rs6769511 in IGF2BP2 was associated with T2DM susceptibility, and the rs4376068-rs4402960-rs6769511 haplotypes in IGF2BP2 was associated with the development of T2DM in a Chinese population.     

基于扎根理论的中成药上市后再评价专家访谈资料分析＊

目的 开展更全面的中成药临床应用资料收集，并对非定量化资料进行定性处理。方法 运用专家深度访谈的方法，以某中成药的临床应用为例，对临床上使用过该中成药的专家进行半结构式访谈，记录并整理访谈资料，引入扎根理论方法进行访谈资料分析。结果 本研究共访谈了10位专家，经扎根理论分析编码，将该中成药的临床应用编码为该药的背景、有效性、安全性、经济便宜性、依从性、临床定位6个主范畴，最终提炼出一个核心类属，并围绕这几个方面的具体信息进行详细分析。结论 通过收集、整理和分析专家经验性信息，丰富了中成药上市后再评价的临床证据集，明确了已上市中成药的临床应用范围，可为后续的临床和科研研究提供证据支持，同时，专家深度访谈和扎根理论分析是对专家经验的挖掘和利用，还可应用于中医经验传承、医者诊疗思维研究等领域。本研究进行了方法探讨和实例验证，以期为后续更高阶的研究奠定基础。