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HSP20 emerges as a novel regulator of autophagy in the heart. Nonetheless, the detailed function of HSP20 in the liver and its effect on autophagy remain unknown. Here, we observed that HSP20 expression is increased in liver tissues from mice and patients with metabolic dysfunction–associated steatotic liver disease (MASLD), formerly known as nonalcoholic fatty liver disease. Liver-specific downregulation of HSP20 mitigates hepatic steatosis and insulin resistance in obese mice, while upregulating HSP20 promotes lipid deposition and hepatocyte cell death. Mechanistically, liquid chromatography–tandem mass spectrometry revealed that HSP20 interacts with phosphorylated extracellular regulated protein kinase 2 (ERK2) and prevents its dephosphorylation by dual specificity phosphatase 6, leading to ERK2-mediated repression of autophagy and resulting in aggravated saturated fatty acid (SFA)–triggered hepatocyte death. Importantly, such adverse effects could be ameliorated by ERK inhibitor. Our data reveal a framework of how HSP20 increases susceptibility of SFA-induced liver injury through enhancing ERK2 phosphorylation, which represents a plausible therapeutic intervention to combat MASLD. Article Highlights: HSP20 expression was increased in the livers of mice and people living with metabolic dysfunction–associated steatotic liver disease and positively correlated with steatosis grade and body mass. Upregulating HSP20 sensitizes hepatocytes to lipotoxicity by inhibiting autophagy. HSP20 interacts with phosphorylated extracellular regulated protein kinase 2 and prevents its dephosphorylation by phosphatase dual specificity phosphatase 6, leading to aggravation of saturated fatty acid–triggered hepatocyte death by suppressing autophagy function. The HSP20-extracellular regulated protein kinase 2 pathway is an important target to maintain liver homeostasis in patients with metabolic disorders. [ABSTRACT FROM AUTHOR]

This study was to explore the functional mechanism of rare earth regulating soybean leaves and the characteristics and functions of differentially expressed proteins under the regulation of rare earth. In this study, Dongnong 42 was used as material, and 30 mg ⋅ L-1 CeCl3 solution was sprayed on soybean leaves at the seedling stage. Tandem mass tag (TMT) quantitative proteomics technique and bioinformatics analysis were used to identify soybean leaf proteins. A total of 8 510 proteins were identified, and 127 differentially expressed proteins (DEPs) in response to rare earth cerium regulation were identified, among which 64 were upregulated and 63 were down-regulated. The gene ontology (GO) annotation indicated that DEPs were mainly involved in metabolic process, cellular process, response to stimulus, biological regulation, and response to a stimulus; DEPs in cell module categories were mainly involved in cells, cell part, organelle, membrane, membrane part, organelle par, and protein-containing complex; DEPs in molecular functional categories were mainly involved in catalytic activity, binding and antioxidant activity. Kyoto encyclopedia of genes and genomes (KEGG) pathway significantly enriched starch and sucrose metabolism, glycolysis/gluconeogenesis, galactose metabolism, pentose phosphate pathway, and MAPK signaling pathway-plant. These DEPs were mainly involved in photosynthesis, glucose metabolism and stress response. Forty-six differential protein interaction networks were identified by protein interaction network analysis. This experiment provided a reference for studies of the mechanism of rare earth cerium regulating soybean leaf function from the proteomic perspective. [ABSTRACT FROM AUTHOR]

Obesity is a global health threat, and the induction of white adipose tissue (WAT) browning presents a promising therapeutic method for it. Recent publications revealed the essential role of protein arginine methyltransferase 4 (PRMT4) in lipid metabolism and adipogenesis, but its involvement in WAT browning has not been investigated. Our initial studies found that the expression of PRMT4 in adipocytes was upregulated in cold-induced WAT browning but downregulated in obesity. Besides, PRMT4 overexpression in inguinal adipose tissue accelerated WAT browning and thermogenesis to protect against high-fat diet–induced obesity and metabolic disruptions. Mechanistically, our work demonstrated that PRMT4 methylated peroxisome proliferator-activated receptor-γ (PPARγ) on Arg240 to enhance its interaction with the coactivator PR domain-containing protein 16 (PRDM16), leading to the increased expression of thermogenic genes. Taken together, our results uncover the essential role of the PRMT4/PPARγ/PRDM16 axis in the pathogenesis of WAT browning. Article Highlights: Protein arginine methyltransferase 4 (PRMT4) expression was upregulated during cold exposure and negatively correlated with body mass of mice and humans. PRMT4 overexpression in inguinal white adipose tissue of mice improved high-fat diet–induced obesity and associated metabolic impairment due to enhanced heat production. PRMT4 methylated peroxisome proliferator-activated receptor-γ on Arg240 and facilitated the binding of the coactivator PR domain-containing protein 16 to initiate adipose tissue browning and thermogenesis. PRMT4-dependent methylation of peroxisome proliferator-activated receptor-γ on Arg240 is important in the process of inguinal white adipose tissue browning. [ABSTRACT FROM AUTHOR]

An experimental study was performed on line-source fire over an inclined surface (ground) to simulate downhill fire spread behavior. The flame geometry and the thermal radiation to both far-field surroundings and near-field inclined surface were investigated. As a basic configuration for wildland fire over a slope, the buoyancy induced natural convection flow along the inclined surface and the constraint of air entrainment by the inclined surface change the flame geometry as well as its radiation emission. Various surface (ground) inclination angles (from 0°-80°), fire source heat release rates and fuels were considered comprehensively with a total of 126 test conditions. Results showed that the flame perpendicular height decreased, while both the flame parallel length and base drag length along the inclined surface increased, with the increased inclination angle. A dimensional analysis was then performed based on the controlling mechanisms, with the dimensionless heat release rate, the density ratio of fuel vapor to air, along with sin α and cos α involved to represent the components in the parallel and perpendicular directions. The flame geometry parameters were well represented by the proposed dimensional analysis. Both the radiation fluxes to far-field surroundings and to near-field inclined surface decreased with the increased inclination angle. The far-field radiation was found to be well characterized by a model based on the soot volume fraction analysis according to single point source model. Concerning the near-field radiation to inclined surface, an inclined cuboid radiative modeling was developed. The predicting results by the proposed model and the experimental values showed good agreement. The present study has explained the controlling physics and proposed non-dimensional functions for flame geometry and modeling the downslope radiation of the line-source fire over the inclined surface, which facilitates the understanding of the wildland fire spread behavior over a slopping ground in the downhill direction. [ABSTRACT FROM AUTHOR]

Abstract: We report here the preparation of Ag-doped LiV3O8 for use as a cathode material in rechargeable lithium ion batteries. Synthesis was carried out by sol–gel methods and low temperature calcination using V2O5 wet gel, LiOH·H2O, and AgNO3 as raw materials. The product was characterized by X-ray diffraction (XRD), and its electrochemical behavior as a cathode material was studied by galvanostatic charge–discharge, cyclic voltammetry, and ac impedance techniques. The experimental results show that Ag-doped LiV3O8 cathodes have greater initial discharge capacity than undoped cathode. And those Ag-doped LiV3O8 electrodes, especially Ag0.04Li0.96V3O8, show the best long-life cycling performance. All of the doped powders show better stability at the 2.6V plateau efficiency, due to their more stable cell impedance. [Copyright &y& Elsevier]

Abstract: LiV3O8 was synthesized by the normal citric acid assisted sol–gel method and an improved citric acid assisted sol–gel method. The improved method compares with the normal method in detail by thermogravimetry (TG), FTIR, X-ray diffraction (XRD), scanning electron microscopy (SEM), charge–discharge test, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Results show that the improved method can synthesize LiV3O8 successfully at much lower temperature than normal method. [Copyright &y& Elsevier]