Citrus aurantium L. extract alleviate depression by inhibiting gut microbiota-mediated inflammation in mice

Gut microbiota plays a crucial role in the pathophysiology of depression.This study aimed to explore the antidepressant effect of mature whole Citrus aurantium fruit extract(FEMC)in the chronic unpredictable mild stress(CUMS)model.The behavioral tests were applied to assess antidepressant effect and 16S rRNA sequencing was used to analyze the changes of gut microbiota.The results showed that the major components of FEMC were naringin and neohesperidin and significantly increased the sucrose preference index of the mice.FEMC also could reduce the feeding latency in an open field test and the rest time in a novelty suppressed feeding test.In addition,FEMC could increase CUMS-induced reduction in the levels of BDNF,PSD95,and SYN in the hippocampus.Moreover,FEMC intervention slightly decreased the ratio of Firmicutes to Bacteroidota.Meanwhile,FEMC reduced the abundance of the Prevotellaceae_Ga6A1_group,[Ruminococcus]_torques_group,which have been reported to be closely related to inflammation.Bioinformatics analysis revealed that mitogen-activated protein kinase(MAPK)signaling pathway and lipopolysaccharide biosynthesis were involved in the anti-inflammatory effect of FEMC in the CUMS animal model.Finally,the ELISA results showed that FEMC could significantly reduce the expression of pro-inflammatory cytokines IL-6 and TNF-αin the serum of depressive mice.Our results suggest FEMC can am eliorate depressive behavior by i nhibiting gut microbiota-mediated inflammation in mice.

Vitamin B3 inhibits apoptosis and promotes autophagy of isletβcells under high glucose stress

Background:Hyperglycemia is a typical symptom of diabetes.High glucose induces apoptosis of isletβcells.While autophagy functions in cytoprotection and autophagic cell death.The interaction between autophagy and apoptosis is important in the modulation of the function of isletβcells.Vitamin B3 can induce autophagy and inhibit isletβapoptosis.Method:The mechanism of vitamin B3-mediated protective effect on the function of isletβcells was explored by the method of western blot,immunofluorescence and flow cytometry.Results:In the present study,high glucose stress increased the apoptosis rate,while vitamin B3 reduced the apoptosis rate.The effect of vitamin B3 on autophagy flux under normal and high glucose stress was also investigated.Vitamin B3 increased the number of autophagosomes and increased the light chain(LC)3-II/LC3-I ratio.In contrast,vitamin B3 decreased sequestosome 1(SQSTM1)/p62 protein expression and inhibited the phosphorylation of mammalian ribosomal protein S6 kinaseβ-1(p70S6K/S6K1),which was a substrate of mammalian target of rapamycin(mTOR)under normal and high glucose stress.To further verify the protective effect of vitamin B3 on apoptosis,we treated isletβcell RIN-m5F with autophagy inhibitor 3-methyladenine(3-MA).Vitamin B3 decreased the apoptosis rate under high glucose stress,while the inhibition of apoptosis by vitamin B3 was blocked after adding 3-MA.Conclusion:Our data suggested that vitamin B3 reduced the apoptosis rate ofβcells,possibly through inducing autophagy under high glucose stress.

Effect of Post-weld Heat Treatment on the Microstructure and Mechanical Properties of 2.25Cr-1Mo-0.25V Ultra-Thick Steel Plate

Ensuring the homogeneous and excellent mechanical properties of 2.25Cr-1Mo-0.25V ultra-thick steel plate is the key to the production of hydrogenation reactor equipment.Thus,it is required to understand the heterogeneity of microstructures and properties of ultra-thick plate after heat treatment.In this work,the effect of post-weld heat treatment(PWHT)on the strength,plasticity,toughness and microstructures of the 193-mm-thick steel plate was investigated,and the formation mechanism of heterogeneity was elucidated.The PWHT decreased the room-and high-temperature yield strength(YS)and ultimate tensile strength(UTS)of the steel plate after normalizing and tempering(NT),while the room-and high-temperature YS and UTS decreased from the surface to the center of 193-mm-thick steel plate.It was attributed to the enhanced decomposition of martensite-austenite(M-A)constituents and coarsening of grains and precipitated carbides.

Effect of Grain Size and Compression Direction on the Hot Deformation Characteristics of High-Cr Ultra-Super-Critical Rotor Steel with Columnar Grains

The columnar grains with a duplex grain size distribution in the ingot increase the difficulty of the hot forging of the as-cast high Cr ultra-super-critical rotor steel.The hot deformation behaviors of the high Cr steel with different initial grain sizes under various compression directions were investigated.The results show that the hot deformation characteristic is strongly grain size and compression direction dependent.The finer grain size and compression direction perpendicular to the columnar grains increase the flow stress and activation energies of hot deformation,comparing with the large grain and deformation direction parallel to the columnar grains.The relationships between flow stress and deformation parameters for the different initial structures conform to the established constitutive equations.The former enhances the critical stress of the dynamic recrystallization(DRX),inhibiting the occurrence of DRX and reducing the dimensions of DRX grains.