Tumour necrosis factor receptor-associated factor 6 (TRAF6) is a ubiquitin E3 ligase that regulates important biological processes. However, the role of TRAF6 in cardiac hypertrophy remains unknown. Here, we show that TRAF6 levels are increased in human and murine hypertrophied hearts, which is regulated by reactive oxygen species (ROS) production. Cardiac-specific Traf6 overexpression exacerbates cardiac hypertrophy in response to pressure overload or angiotensin II (Ang II) challenge, whereas Traf6 deficiency causes an alleviated hypertrophic phenotype in mice. Mechanistically, we show that ROS, generated during hypertrophic progression, triggers TRAF6 auto-ubiquitination that facilitates recruitment of TAB2 and its binding to transforming growth factor beta-activated kinase 1 (TAK1), which, in turn, enables the direct TRAF6–TAK1 interaction and promotes TAK1 ubiquitination. The binding of TRAF6 to TAK1 and the induction of TAK1 ubiquitination and activation are indispensable for TRAF6-regulated cardiac remodelling. Taken together, we define TRAF6 as an essential molecular switch leading to cardiac hypertrophy in a TAK1-dependent manner.
More serious coronary atherosclerosis was observed in CHD patients with H. pylori +CagA+ infection. H. pylori +CagA+ infection might be involved in coronary atherosclerosis by modifying serum lipids, enhancing LDL oxidation, and activating the inflammatory responses.
Background. In recent years, with the popularity of CHM, its hepatotoxicity has also been increasingly noticed. However, there are still veils on causative herbs and clinical characteristics. Aim. To systematically review data on CHM induced liver injury with particular focus on causative herbs and clinical characteristics. Methods. Using terms related to CHM and liver injury, PubMed and three Chinese electronic databases were searched, which was limited to the past 5 years. Publications meeting our eligibility criteria were included and further analyzed. Results. In total, 4 single herbs, 21 patent drugs, and 4 decoctions were reported to be of hepatotoxicity, with He-Shou-Wu being the most common one (65/114). Dang-Gui and other 5 herbs were the most common ingredients of patent drugs and decoctions. All patients were assessed using the RUCAM scale, with 26 being highly probable and 28 being probable. For these 54 cases, the latent period was 30 (47) days, and 81.48% were labeled as hepatocellular injuries. Most patients (96.3%) recovered, apart from the fact that one died and one is receiving liver transplantation. Conclusions. CHM should be used carefully for hepatotoxicity. Liver injury from CHM is similar to that from conventional medicines in clinical characteristics. Details about causative herbs should be illustrated, and more RUCAM should be used in future.
RationaleIt is clear that lipid disorder and inflammation are associated with cardiovascular diseases and underlying atherosclerosis. Nur77 has been shown to be involved in inflammatory response and lipid metabolism.ObjectiveHere, we explored the role of Nur77 in atherosclerotic plaque progression in apoE−/− mice fed a high-fat/high cholesterol diet.Methods and ResultsThe Nur77 gene, a nuclear hormone receptor, was highly induced by treatment with Cytosporone B (Csn-B, specific Nur77 agonist), recombinant plasmid over-expressing Nur77 (pcDNA-Nur77), while inhibited by treatment with siRNAs against Nur77 (si-Nur77) in THP-1 macrophage-derived foam cells, HepG2 cells and Caco-2 cells, respectively. In addition, the expression of Nur77 was highly induced by Nur77 agonist Csn-B, lentivirus encoding Nur77 (LV-Nur77), while silenced by lentivirus encoding siRNA against Nur77 (si-Nur77) in apoE−/− mice fed a high-fat/high cholesterol diet, respectively. We found that increased expression of Nur77 reduced macrophage-derived foam cells formation and hepatic lipid deposition, downregulated gene levels of inflammatory molecules, adhesion molecules and intestinal lipid absorption, and decreases atherosclerotic plaque formation.ConclusionThese observations provide direct evidence that Nur77 is an important nuclear hormone receptor in regulation of atherosclerotic plaque formation and thus represents a promising target for the treatment of atherosclerosis.
Our results indicate that the new upper cut-off values of serum ALT and AST are markedly lower than current standards and may be valuable for the evaluation of liver function.
Background and Aims
Milk fat globule–epidermal growth factor–factor 8 (MFGE8) has been shown to be a critical extracellular molecule that mediates apoptotic signaling in the pathological process of nonalcoholic fatty liver disease (NAFLD). MFGE8 is abundantly expressed in hepatocytes, but its function in the pathogenesis of NAFLD has not been characterized.
Approach and Results
In our current study, hepatic MFGE8 showed a protective role in the pathogenesis of NAFLD. Hepatic MFGE8 deletion largely exacerbated lipid accumulation and inflammatory responses in the liver in response to overnutrition. Mechanistically, intercellular MFGE8 was shown to directly bind to apoptosis signal‐regulating kinase 1 (ASK1) and to inhibit its dimerization and phosphorylation under a normal diet. However, under metabolic challenges, decreased cytoplasmic MFGE8 facilitated the dimerization and phosphorylation of ASK1 and subsequent mitogen‐activated protein kinase signaling in hepatocytes.
Conclusions
Hepatic MFGE8 is an endogenous inhibitor that halts the progression of hepatic steatosis and inflammation. Metabolic challenge–induced loss of intracellular MFGE8 facilitates ASK1 dimerization and phosphorylation. Therefore, maintaining hepatic MFGE8 levels may serve as an alternative strategy for the treatment of NAFLD.
China's largest freshwater lake, Poyang Lake, is characterized by rapid changes in its inundation area and hydrodynamics, so in this study, a hydrodynamic model of Poyang Lake was established to simulate these long-term changes. Inundation information was extracted from Moderate Resolution Imaging Spectroradiometer (MODIS) remote sensing data and used to calibrate the wetting and drying parameter by assessing the accuracy of the simulated inundation area and its boundary. The bottom friction parameter was calibrated using current velocity measurements from Acoustic Doppler Current Profilers (ADCP). The results show the model is capable of predicting the inundation area dynamic through cross-validation with remotely sensed inundation data, and can reproduce the seasonal dynamics of the water level, and water discharge through a comparison with hydrological data. Based on the model results, the characteristics of the current velocities of the lake in the wet season and the dry season of the lake were explored, and the potential effect of the current dynamic on water quality patterns was discussed. The model is a
OPEN ACCESSRemote Sens. 2015, 7 4859 promising basic tool for prediction and management of the water resource and water quality of Poyang Lake.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.