Aralia elata inhibits neurodegeneration by downregulating O-GlcNAcylation of NF-κB in diabetic mice

AIM： To investigate the role of O-GIcNAcylation of nuclear factor-kappa B （NF-KB） in retinal ganglion cell （RGC） death and analysedthe effect of Aralia elata （AE） on neurodegen- eration in diabetic mice. METHODS： C57BL/6mice with streptozotocin-induced diabetes were fed daily with AE extract or control （CTL） diet at the onset of diabetes mellitus （DM）. Two months af- tar injection of streptozotocin or saline, the degree of cell death and the expression of O-GIcNAc transferase （OGT）, N-acetyl-b-D-glucosaminidase （OGA）, O-GIcNAcylated pro- teins, and O-GIcNAcylation of NF-KB were examined. RESULTS： AE did not affect the metabolic status of diabetic mice. The decrease in the inner retinal thickness （P〈0.001 vs CTL, P〈0.01 vs DM） and increases in RGCs with terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling （P〈0.001 vs CTL, P〈0.0001 vs DM）, glial activation, and active caspase-3 （P〈0.0001 vs CTL, P〈0.0001 vs DM） were blocked in diabetic retinas of AE extract-fed mice. Expression levels of protein O-GIcNAcylation and OGT were increased in diabetic retinas （P〈0.0001 vs CTL）, and the level of O-GIcNAcylation of the NF-KB p65 subunit was higher in diabetic retinas than in controls （P〈0.0001 vs CTL）. AE extract downregulated O-GIcNAcylation of NF-KB and prevented neurodegeneration induced by hyperglycemia （P〈0.0001 vs DM）. CONCLUSION： O-GIcNAcylation of NF-KB is concerned in neuronal degeneration and that AE prevents diabetes-in- duced RGC apoptosis via downregulation of NF-KB O-GI- cNAcylation. Hence, O-GIcNAcylation may be a new object for the treatment of DR, and AE may have therapeutic pos- sibility to prevent diabetes-induced neurodegeneration.

In-situ formation of MOF derived mesoporous Co3N/amorphous N-doped carbon nanocubes as an efficient electrocatalytic oxygen evolution reaction

The suitable materials,metal nitrides,are a promising class of electrocatalyst materials for a highly efficient oxygen evolution reaction (OER) because they exhibit superior intrinsic conductivity and have higher sustainability than oxide-based materials.To our knowledge,for the first time,we report a designable synthesis of three-dimensional (3D) and mesoporous Co3N@ amorphous N-doped carbon (AN-C) nanocubes (NCs) with well-controlled open-framework structures via monodispersed Co3[Co(CN)6]2 Prussian blue analogue (PBA) NC precursors using in situ nitridation and calcination processes.Co3N@AN-C NCs (2 h) demonstrate better OER activity with a remarkably low Tafel plot (69.6 mV-dec-1),low overpotential of 280 mV at a current density of 10 mA-crrf2.Additionally,excellent cycling stability in alkaline electrolytes was exhibited without morphological changes and voltage elevations,superior to most reported hierarchical structures of transition-metal nitride particles.The presented strategy for synergy effects of metal-organic frameworks (MOFs)-derived transition-metal nitrides-carbon hybrid nanostructures provides prospects for developing high-performance and advanced electrocatalyst materials.