Objective To investigate the effects of regenerating islet-derived protein 3β(Reg3β)on intestinal function and glycolysis in septic mice,as well as its role in promoting lactylation.Methods ① In vivo experiments:a total of 36 adult male C57BL/6 mice,including wild-type(WT)and Reg3β knockout(KO)mice,were randomly divided into six groups using a random number table:WT sham group,WT cecal ligation and puncture(CLP)-induced sepsis group(WT CLP group),WT sham+Reg3β intervention group(WT sham group),WT CLP+Reg3β intervention group(WT CLP+Reg3β group),KO sham group,and KO CLP group(n=6 per group).Blood glucose levels were measured at 24 hours and 48 hours after modeling;At 48 hours after modeling,ileum tissues were collected for hematoxylin-eosin(HE)staining to observe histopathological changes,immunofluorescence staining was performed to assess the positive expression levels of lactylated proteins,Western blotting was used to detect the expression levels of lactylated proteins in ileum tissues.② In vitro experiments:Cultured RAW264.7 cells were randomly divided into four groups using a random number table:blank control group,lipopolysaccharide(LPS)-induced sepsis model group(LPS group),Reg3β group,and LPS+Reg3β group.After 24 hours of drug induction,cells were collected,and Western blotting was performed to measure the levels of lactylated proteins,the culture medium was collected to determine lactylation levels.Results ① Histopathological observations showed that compared with the WT CLP group,the WT CLP+Reg3β group exhibited milder villus breakage and inflammatory cell infiltration.The KO CLP group showed more severe damage,with significantly shortened intestinal villi and separation of the epithelial layer from the lamina propria.Compared with the WT CLP group,blood glucose levels were significantly higher in the KO CLP group(mmol/L:6.83±1.15 vs.4.78±1.37,P<0.05).Both Western blotting and immunofluorescence staining results indicated that,compared with the WT CLP group,lactylation levels were significantly decreased in the KO CLP group[lactylated protein expression(lactylated protein/β-actin):0.48±0.20 vs.0.78±0.09;positive lactylated protein expression(mean fluorescence intensity):59.84±6.02 vs.100.00±5.26,both P<0.01].② Western blotting results of RAW264.7 cells cultured for 24 hours showed that compared with the LPS group,the LPS+Reg3β group exhibited significantly increased lactylated protein expression levels(lactylated protein expression/β-actin:3.67±0.48 vs.1.64±0.49,P<0.01).Compared with the blank control group,the lactate levels in the culture medium of the LPS group were significantly increased(mmol/L:4.95±0.20 vs.3.82±0.09,P<0.01).Compared with the LPS group,the lactate levels in the culture medium of the LPS+Reg3β group were also significantly increased(mmol/L:6.03±0.32 vs.4.95±0.20,P<0.01).Conclusion Reg3β promotes intestinal protein lactylation and exerts a protective effect on the intestine in sepsis,suggesting that Reg3β may serve as a novel therapeutic target for sepsis.

Objective To investigate the effects of regenerating islet-derived protein 3β(Reg3β)on intestinal function and glycolysis in septic mice,as well as its role in promoting lactylation.Methods ① In vivo experiments:a total of 36 adult male C57BL/6 mice,including wild-type(WT)and Reg3β knockout(KO)mice,were randomly divided into six groups using a random number table:WT sham group,WT cecal ligation and puncture(CLP)-induced sepsis group(WT CLP group),WT sham+Reg3β intervention group(WT sham group),WT CLP+Reg3β intervention group(WT CLP+Reg3β group),KO sham group,and KO CLP group(n=6 per group).Blood glucose levels were measured at 24 hours and 48 hours after modeling;At 48 hours after modeling,ileum tissues were collected for hematoxylin-eosin(HE)staining to observe histopathological changes,immunofluorescence staining was performed to assess the positive expression levels of lactylated proteins,Western blotting was used to detect the expression levels of lactylated proteins in ileum tissues.② In vitro experiments:Cultured RAW264.7 cells were randomly divided into four groups using a random number table:blank control group,lipopolysaccharide(LPS)-induced sepsis model group(LPS group),Reg3β group,and LPS+Reg3β group.After 24 hours of drug induction,cells were collected,and Western blotting was performed to measure the levels of lactylated proteins,the culture medium was collected to determine lactylation levels.Results ① Histopathological observations showed that compared with the WT CLP group,the WT CLP+Reg3β group exhibited milder villus breakage and inflammatory cell infiltration.The KO CLP group showed more severe damage,with significantly shortened intestinal villi and separation of the epithelial layer from the lamina propria.Compared with the WT CLP group,blood glucose levels were significantly higher in the KO CLP group(mmol/L:6.83±1.15 vs.4.78±1.37,P<0.05).Both Western blotting and immunofluorescence staining results indicated that,compared with the WT CLP group,lactylation levels were significantly decreased in the KO CLP group[lactylated protein expression(lactylated protein/β-actin):0.48±0.20 vs.0.78±0.09;positive lactylated protein expression(mean fluorescence intensity):59.84±6.02 vs.100.00±5.26,both P<0.01].② Western blotting results of RAW264.7 cells cultured for 24 hours showed that compared with the LPS group,the LPS+Reg3β group exhibited significantly increased lactylated protein expression levels(lactylated protein expression/β-actin:3.67±0.48 vs.1.64±0.49,P<0.01).Compared with the blank control group,the lactate levels in the culture medium of the LPS group were significantly increased(mmol/L:4.95±0.20 vs.3.82±0.09,P<0.01).Compared with the LPS group,the lactate levels in the culture medium of the LPS+Reg3β group were also significantly increased(mmol/L:6.03±0.32 vs.4.95±0.20,P<0.01).Conclusion Reg3β promotes intestinal protein lactylation and exerts a protective effect on the intestine in sepsis,suggesting that Reg3β may serve as a novel therapeutic target for sepsis.

Ubiquitination, an essential post-transcriptional modification (PTM), plays a vital role in nearly every biological process, including development and growth. Despite its functions in plant reproductive development, its targets in rice panicles remain unclear. In this study, we used proteome-wide profiling of lysine ubiquitination in rice (O. sativa ssp. indica) young panicles. We created the largest ubiquitinome dataset in rice to date, identifying 1638 lysine ubiquitination sites on 916 unique proteins. We detected three conserved ubiquitination motifs, noting that acidic glutamic acid (E) and aspartic acid (D) were most frequently present around ubiquitinated lysine. Enrichment analysis of Gene Ontology (GO) annotations and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of these ubiquitinated proteins revealed that ubiquitination plays an important role in fundamental cellular processes in rice young panicles. Interestingly, enrichment analysis of protein domains indicated that ubiquitination was enriched on a variety of receptor-like kinases and cytoplasmic tyrosine and serine-threonine kinases. Furthermore, we analyzed the crosstalk between ubiquitination, acetylation, and succinylation, and constructed a potential protein interaction network within our rice ubiquitinome. Moreover, we identified ubiquitinated proteins related to pollen and grain development, indicating that ubiquitination may play a critical role in the physiological functions in young panicles. Taken together, we reported the most comprehensive lysine ubiquitinome in rice so far, and used it to reveal the functional role of lysine ubiquitination in rice young panicles.
Acetylation ; Lysine/metabolism* ; Oryza/metabolism* ; Plant Proteins/metabolism* ; Protein Interaction Maps ; Protein Processing, Post-Translational ; Proteome/metabolism* ; Ubiquitin/metabolism* ; Ubiquitination

OBJECTIVETo confirm that the severity of inflammation can promote the colitis-associated colorectal cancer(CAC) and explore the function of STAT3 signal pathway in CAC.

METHODSMutagenic agent azoxymethane(AOM) and pro-inflammatory agent dextran sodium sulfate salt (DSS) were used to develop a mouse model of CAC. By changing the concentration of DSS (0, 1% and 2% respectively), the mouse model with different extent of severity of inflammation was developed and the risk of carcinogenesis among these groups was compared. The expression of STAT3 signal pathway was detected by immunohistochemistry staining.

RESULTSIn the evaluation of inflammatory severity, disease activity index, histopathological inflammation scores and the expression of pro-inflammation chemokines such as TNF-α, IL-6 and IL-12 in the higher inflammatory response group were higher than that in the lower inflammatory response group. The incidence of colorectal tumor was 100%(12/12) in the higher inflammatory response group and the incidence of colorectal tumor was 58.3%(7/12) in the lower inflammatory response group, and the difference between these two group was statistically significant (P<0.05). The multiplicity(number of tumors/colon) was 12.5±0.5 in the higher inflammatory response group and the multiplicity was 6.6±1.0 in the lower inflammatory response group, and the difference between these two groups was statistically significant (P<0.001). The tumor load(sum of tumor diameters per mouse) in the higher inflammatory response group was 44.2±2.4 mm and that in the lower inflammatory response group was only 18.7±2.7 mm, and the difference between these two groups was statistically significant (P<0.0001). Moreover, the expression of p-STAT3 (Tyr705) was higher in colitis tissue of the higher inflammatory response group than that of the lower inflammatory response group.

CONCLUSIONSInflammation can promote the colitis-associated CAC. And the activation of STAT3 signal pathway may promote the development of CAC.

Animals ; Azoxymethane ; Colitis ; complications ; Colonic Neoplasms ; Colorectal Neoplasms ; etiology ; pathology ; Dextran Sulfate ; Disease Models, Animal ; Immunohistochemistry ; Inflammation ; Interleukin-6 ; Mice ; Mice, Inbred C57BL ; STAT3 Transcription Factor ; Signal Transduction ; Tumor Necrosis Factor-alpha