Objective To investigate the protective effect and underlying mechanism of human umbilical cord mesenchymal stem cell-derived exosomes (hucMSC-Exo) on renal ischemia-reperfusion injury (IRI). Methods hucMSC-Exos were isolated and characterized. A mouse renal IRI model was established and the animals were divided into Sham, IRI, IRI+hucMSC-Exo, IRI+hucMSC-Exo+JY-2 and Sham+JY-2 groups. Serum creatinine (Scr) and blood urea nitrogen (BUN) were measured. Hematoxylin-eosin (HE) staining was used to evaluate renal histopathology. Enzyme-linked immune absorbent assay was performed to determine serum interleukin (IL)-1β and IL-18 levels. Western blotting was used to detect the expression of activating transcription factor 3 (ATF3), Toll-like receptor 4 (TLR4), nuclear factor (NF)-κB, NOD-like receptor protein 3 (NLRP3), cysteineyl aspartate specific proteinase (Caspase)-1 p20 and Gasdermin D(GSDMD). Real-time fluorescent quantitative polymerase chain reaction was employed to measure ATF3, TLR4 and NF-κB messenger RNA (mRNA). Immunohistochemistry was conducted to examine NLRP3, Caspase-1 p20 and GSDMD. An in vitro hypoxia/reoxygenation (H/R) model was established in HK-2 cells and divided into Control, H/R, H/R+hucMSC-Exo, H/R+hucMSC-Exo+JY-2 and Control+JY-2 groups. Western blotting was used to detect the expression of ATF3, TLR4 and NF-κB. Real-time fluorescent quantitative polymerase chain reaction was used to measure NLRP3, GSDMD and Caspase-1 mRNA. Results HucMSC-Exos were successfully isolated and identified. Compared with the Sham group, the IRI group exhibited elevated Scr and BUN, higher tubular injury scores, increased protein expression levels of ATF3, TLR4, NF-κB p65, NLRP3, Caspase-1 p20 and GSDMD, and raised mRNA expression levels of ATF3, TLR4, NF-κB. Compared with the IRI group, the IRI+hucMSC-Exo group showed decreased Scr and BUN, lower tubular injury scores, up-regulated ATF3 protein and mRNA, down-regulated TLR4, NF-κB p65, NLRP3, Caspase-1 p20 and GSDMD protein, and declined TLR4 and NF-κB mRNA. Compared with the IRI+hucMSC-Exo group, the IRI+hucMSC-Exo+JY-2 group exhibited increased Scr and BUN levels, elevated renal tubular injury scores, decreased ATF3 protein expression levels, elevated protein expression levels of TLR4, NF-κB p65, NLRP3, Caspase-1 p20, and GSDMD, decreased ATF3 mRNA expression levels, and elevated mRNA expression levels of TLR4 and NF-κB. (all P < 0.05). Compared with the Control group, the expression levels of ATF3, TLR4 and NF-κB p65 proteins were increased in the H/R group, and the expression levels of NLRP3, Caspase-1 and GSDMD mRNA were increased. Compared with the H/R group, the expression level of ATF3 protein was increased, the expression levels of TLR4 and NF-κB p65 proteins were decreased, and the expression levels of NLRP3, Caspase-1 and GSDMD mRNA were decreased in the H/R+hucMSC-Exo group. Compared with the H/R+hucMSC-Exo group, the expression level of ATF3 protein was decreased, the expression levels of TLR4 and NF-κB p65 proteins were increased, and the expression levels of NLRP3, Caspase-1 and GSDMD mRNA were increased in the H/R+hucMSC-Exo+JY-2 group (all P < 0.05). Conclusions HucMSC-Exos alleviate renal IRI by up-regulating ATF3, thereby negatively regulating the TLR4/NF-κB signaling pathway and subsequently inhibiting pyroptosis.

OBJECTIVE: To explore the genetic etiology of 46 Chinese pedigrees affected with Hereditary multiple exostoses (HME) and provide genetic counseling and reproductive intervention. METHODS: Whole-exome sequencing and Sanger sequencing were carried out on 87 patients from the 46 pedigrees to analyze the variants of EXT1 and EXT2 genes. Pathogenicity of the variants was assessed based on the guidelines from the American College of Medical Genetics and Genomics and Association for Molecular Pathology (ACMG/AMP). Prenatal diagnosis and preimplantation genetic testing (PGT) were provided for couples with identified pathogenic mutations. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: LL-SC-SG-2014-010). RESULTS: In total 17 and 22 pathogenic variants were respectively identified in the EXT1 and EXT2 genes, among which 5 EXT1 and 12 EXT2 variants were unreported previously. Three patients with no family history were found to harbor de novo variants of the EXT1 gene. Twenty nine couples had opted for PGT or underwent prenatal diagnosis following natural conception, and 17 healthy babies were born. CONCLUSION This study has clarified the genetic etiology of 45 HME pedigrees and identified 17 novel variants, which has enriched the mutational spectrum of the EXT1 and EXT2 genes. Reproductive intervention through PGT and prenatal diagnosis have prevented the recurrence of HME in these families.
Humans ; Female ; Male ; Pedigree ; Exostoses, Multiple Hereditary/diagnosis* ; N-Acetylglucosaminyltransferases/genetics* ; Adult ; Exostosin 1 ; Asian People/genetics* ; Genetic Testing ; Exostosin 2 ; Mutation ; China ; Prenatal Diagnosis ; Pregnancy ; Genetic Counseling ; Preimplantation Diagnosis ; Exome Sequencing ; East Asian People

ObjectiveProtein-protein interactions (PPIs) are fundamental to the execution of biological functions within living cells. However, traditional biochemical methods, such as co-immunoprecipitation (Co-IP), often fail to capture transient, weak, or membrane-associated interactions due to the stringent detergent requirements for cell lysis. Proximity labeling (PL) has emerged in recent years as a transformative technology for mapping the proteomes of specific subcellular compartments and identifying dynamic interactomes in situ. Golgi protein 73 (GP73, also known as GOLPH2), a resident type II Golgi transmembrane protein, is a well-recognized clinical biomarker for liver diseases, including hepatocellular carcinoma (HCC). Despite its clinical significance, the comprehensive physiological and pathological functions of GP73 remain partially understood. This study aims to establish an APEX2-mediated proximity labeling system specifically targeting GP73 to map its interactome in a living cellular environment, thereby providing new insights into its molecular roles and regulatory mechanisms. MethodsTo achieve spatial specificity, we first constructed a stable cell line expressing a fusion protein consisting of GP73 and the engineered soybean peroxidase APEX2. The localization of the GP73-APEX2 fusion protein was validated to ensure it correctly targeted the Golgi apparatus. The proximity labeling reaction was initiated by incubating the cells with biotin-phenol (BP) for 30 min, followed by a brief (1 min) treatment with1 mmol/L hydrogen peroxide (H₂O₂). This catalytic reaction converts BP into highly reactive, short-lived biotin-phenoxyl radicals that covalently attach to endogenous proteins within a small labeling radius of the GP73-APEX2 enzyme. Subsequently, the cells were quenched, and biotinylated proteins were enriched using high-affinity streptavidin-coated magnetic beads. The captured “neighbor” proteins were subjected to on-bead digestion and analyzed via liquid chromatography-tandem mass spectrometry (LC-MS/MS) for high-throughput identification. Rigorous bioinformatics analysis, including Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and protein-protein interaction network mapping, was performed to interpret the biological significance of the identified candidates. ResultsOur results demonstrate the successful establishment of a robust and sensitive APEX2-based proximity labeling system for GP73. We identified a total of 95 high-confidence interacting proteins that were significantly enriched in the GP73 proximity proteome compared to control groups. Bioinformatics analysis revealed that these interactors were predominantly associated with biological processes such as vesicular transport, protein localization, and, most notably, molecular functions related to “ribosome binding” and “translation regulation”. This suggested an unexpected role for the Golgi-resident GP73 in the cellular translation machinery. To validate these findings, we performed targeted biochemical assays which confirmed a direct interaction between GP73 and the subunits of the eukaryotic translation initiation factor 3 (eIF3) complex, specifically EIF3G and EIF3I. Furthermore, functional validation using the surface sensing of translation (SUnSET) assay—a non-radioactive method to monitor protein synthesis—revealed that the overexpression of GP73 significantly promoted global protein translation levels in the cell, whereas its depletion or inhibition resulted in reduced translation efficiency. ConclusionThis study successfully utilized APEX2-mediated proximity labeling to provide the first systematic map of GP73 interactome in living cells. Our findings uncover a novel, unconventional function of GP73 as a regulator of cellular protein translation, likely mediated through its interaction with the eIF3 complex. This discovery significantly broadens our understanding of the biological roles of GP73 beyond its traditional function in the Golgi apparatus and suggests that it may act as a bridge between Golgi-related trafficking and the protein synthesis machinery. Furthermore, the technical framework established in this study provides a valuable template for investigating other complex organelle-associated protein networks and resolving transient macromolecular interactions in various physiological and pathological contexts.

Pathological cardiac hypertrophy is an early and significant cardiac structural charac-teristic that contributes to the onset and progression of heart failure(HF).Its mainly structural feature is the abnormally enlarged cardiomyocyte.Effective intervention targets for abnormally en-larged cardiomyocyte remain to be identified.Previous studies have shown that the cellular shape and size can be regulated by the actin related protein 2/3(Arp2/3)complex,which is an actin-binding protein complex involved in the actin nucleation and assembly.However,the roles of the Arp2/3 complex in cardiomyocyte hypertrophy remain unknown.Here our study identifies its no-vel roles in the occurrence and development of cardiomyocyte hypertrophy.We found that mRNA levels of all subunits from the Arp2/3 complex are significantly upregulated(P<0.05)in the an-giotensin II(Ang Ⅱ)-induced neonatal rat primary and H9c2 cardiomyocyte hypertrophy.Fur-ther studies showed that siRNA-directed ARPC2 silencing inhibits the reactivation of fetal genes and enlargement of cardiomyocyte area induced by Ang Ⅱ in neonatal rat primary cardiomyocytes(NRCMs)and H9c2 cells(P<0.05).In addition,the upstream activators of the Arp2/3 com-plex including SH3 protein interacting with Nck,90 kD(SPIN90)and Ras-related C3 botulinum toxin substrate 1(Rac1)/WASp family Verprolin-homologous protein-2(WAVE-2)are upregu-lated(P<0.05)in Ang Ⅱ-induced neonatal rat primary and H9c2 cardiomyocyte hypertrophy,indicating the excessive activation of the Arp2/3 complex.We further show that CK666,a specif-ic Arp2/3 complex inhibitor,prevents the reactivation of fetal genes and the enlargement of car-diomyocyte area induced by Ang Ⅱ in NRCMs and H9c2 cells(P<0.05).Our results reveal that the Arp2/3 complex plays a crucial role in Ang Ⅱ-induced cardiomyocyte hypertrophy,which is beneficial to further studies about the molecular mechanisms by which the Arp2/3 complex regu-lates pathological cardiac hypertrophy.

Aim To reveal the mechanism of CIP4 homologs protein 1(RICH1)are involved in the regu-lation of myocardial fibrosis.Methods Mouse cardiac fibroblasts(MCFs)cells were treated with transforming growth factor-β(TGF-β1)to induce the formation of a myocardial fibrosis cell model;the level of the target protein was detected by Western blotting;and the RICH1 gene was detected by transfection of the cells with plasmid.The RICH1 gene was overexpressed(RICH 1 OE)using plasmid transfection;the RICH1 gene was silenced using siRNA fragment(siRICH1);and the expression levels of myocardial fibrosis marker genes,such as Col1 a1,Col3 a1,and Acta2,were de-tected using RT-qPCR.Results RICH1 was signifi-cantly down-regulated in TGF-β1-treated MCFs;the expression levels of myocardial fibrosis marker genes,such as Col1 a1,Col3a1,and Acta2,were down-regu-lated in the RICH1 OE+TGF-β1 group;and in the siRICH1+TGF-β1 group,myocardial fibrosis marker genes,such as Col1 a1,Col3a1 and Acta2 were up-regulated at the expression level;phosphorylated SMAD2(p-SMAD2)and phosphorylated SMAD3(p-SMAD3)levels were down-regulated in the siRICH1 OE+TGF-β1 group.p-SMAD2 and P-SMAD3 levels were upregulated in the siRICH1+TGF-β1 group.Conclusion RICH1 inhibits TGF-β1-induced myo-cardial fibrosis;RICH1 inhibits TGF-β1-induced myo-cardial fibrosis by negatively regulating the SMAD2/3 signaling pathway.

Objective:To summarize the technical difficulties, key points and cosmetic effects of Ti-loop patch application in breast shaping of immediate reconstruction with omental flap transplantation after mastectomy.Methods:The clinical data of 90 cases with breast cancer who underwent immediate breast reconstruction by using laparoscopically harvested omental flap alone or combined with prosthesis after nipple and areola complex sparing mastectomy from May. 2020 to Jan. 2023 in Hunan Cancer Hospital was retrospectively analyzed. All patients were female between 16 and 55 years old with the average age of 42. Their courses of the disease range from 5 to 26 months with the mean of 15.5 months. These patients received mastectomy with conservation of nipple and areola, and then the greater omentum with right pedicle were harvested laparoscopically. Ti-loop patch was used to hang and fix the greater omentum as a support. 27 patients accepted immediate breast reconstruction with pedicled greater omentum alone, while 63 subjects with greater omentum and gel prosthesis. Among them, contralateral breast contraction and lift was operated on 9 cases.Results:All the pedicled greater omentum successfully survived, and wound surfaces of donor and recipient sites healed at stage I. Axillary lymph node dissection and postoperative radiotherapy were performed on 14 patients with positive pathological examination of sentinel lymph nodes. Breasts of two patients were found to be smaller after postoperative radiotherapy. All 90 subjects were followed up for 5 to 32 months, and the average follow-up period was 16.4 months. The reconstructed breasts were good in shape and tactile sensation. Only punctate scars were observed in donor sites of abdomen. All patients recovered with no upper limb lymphedema, no short and long term complications in abdomen, and only one patient had papillary recurrence without distant metastasis.Conclusions:The omental flap is hard to be sutured and shaped in the reconstructed breast, while easily to be avulsed and form hematoma. The application of Ti-loop patch, which could semi-surround and wrap the greater omentum, and suspend and fix it on the chest wall in upper pole of the breast as a support, can significantly improve the reconstruction effect.

Objective:To investigate the levels of C reactive protein(CRP)and interleukin(IL)-6 in patients with myocardial infarction(MI)and their association with cardiac function.Methods:We enrolled 140 MI patients ad-mitted to Sanya Harbin Medical University Hongsen Hospital Co.,Ltd between January 2020 and December 2022,as MI group.According to coronary stenotic severity,they were divided into mild group(n=62),moderate group(n=41)and severe group(n=37),and 75 healthy individuals who underwent physical examination simultaneously were selected as control group.Serum CRP,IL-6,cardiac troponin Ⅰ(cTnⅠ)and creatine kinase isoenzyme MB(CK-MB)levels were measured by automatic biochemical analyzer,and left ventricular ejection fraction(LVEF)was assessed by echocardiography.Above-mentioned indexes were compared between MI group and control group,and among groups of different coronary disease severity.Pearson/Spearman correlation was used to analyze the asso-ciation of serum CRP and IL-6 levels with Gensini score,cTnⅠ,CK-MB levels,and LVEF in MI patients.Diag-nostic value of serum CRP and IL-6 levels for MI was analyzed by receiver operating characteristic(ROC)curve.Results:Compared with participants in control group,those in MI group had significant higher serum CRP,IL-6,cTnⅠ and CK-MB,and significant lower LVEF(P＜0.001 all).Serum CRP,IL-6,cTnⅠ and CK-MB levels sig-nificantly increased,and LVEF significant decreased in the order of mild group,moderate group and severe group(P＜0.01 all).Pearson/Spearman correlation analysis showed that serum CRP and IL-6 levels were positively cor-related with Gensini score,cTnⅠ,and CK-MB levels(r=0.496～0.646,P＜0.001all),and negatively correlated with LVEF(r=-0.530,-0.572,P＜0.001 all)in MI patients.ROC curve showed that the area under the curve(AUC)of CRP combined IL-6 diagnosing MI was 0.856(95％CI 0.802～0.900),which was significantly higher than those of CRP(AUC=0.770,95％CI 0.708～0.824)and IL-6(AUC=0.793,95％CI 0.733～0.845)alone(Z=3.295,2.877,P＜0.01 all).Conclusion:Serum CRP and IL-6 levels rise in MI patients,and they are closely associated with increased severity of coronary artery disease and reduced cardiac function.

Protein-protein interactions play an extremely important role in the biochemical functions of cells,and in-depth analysis of protein interactions is the key to understanding cellular life activities.In this study,we systematically mined the interacting proteins of Golgi protein 73(GP73)using classical immunoprecipitation combined with mass spectrometry,and sought to further analyze the molecular func-tion of GP73.Hepatocellular carcinoma cell line HepG2 was selected,and a stable cell line overexpress-ing GP73-3Flag was constructed using lentiviral infection technology.A total of 78 high-confidence GP73 interacting proteins were identified by immunoprecipitation coupled with mass spectrometry.Bioinformat-ics analyses suggested that GP73 interacted with nearly 40 cytosolic proteins and participated in the bio-logical processes of RNA transport,splicing,and translation.Further immunofluorescence and cytosolic protein isolation experiments confirmed the cytosolic localization of GP73 in a variety of tumor cells.Based on the 78 interacting proteins,we further screened protein interaction networks related to mRNA splicing and verified the existence of interactions between GP73 and seven proteins,including HNRN-PH3,SMN1,RBM14,andNCBP1,by co-immunoprecipitation experiments.In addition,minigene spli-cing assay results indicated that GP73 inhibited the splicing efficiency of pre-mRNA by cells.This study contributes to the expansion of knowledge regarding the function of GP73 and aids in elucidating its criti-cal role in cell biology and its potential association with diseases.

Objective:To investigate the levels of C reactive protein(CRP)and interleukin(IL)-6 in patients with myocardial infarction(MI)and their association with cardiac function.Methods:We enrolled 140 MI patients ad-mitted to Sanya Harbin Medical University Hongsen Hospital Co.,Ltd between January 2020 and December 2022,as MI group.According to coronary stenotic severity,they were divided into mild group(n=62),moderate group(n=41)and severe group(n=37),and 75 healthy individuals who underwent physical examination simultaneously were selected as control group.Serum CRP,IL-6,cardiac troponin Ⅰ(cTnⅠ)and creatine kinase isoenzyme MB(CK-MB)levels were measured by automatic biochemical analyzer,and left ventricular ejection fraction(LVEF)was assessed by echocardiography.Above-mentioned indexes were compared between MI group and control group,and among groups of different coronary disease severity.Pearson/Spearman correlation was used to analyze the asso-ciation of serum CRP and IL-6 levels with Gensini score,cTnⅠ,CK-MB levels,and LVEF in MI patients.Diag-nostic value of serum CRP and IL-6 levels for MI was analyzed by receiver operating characteristic(ROC)curve.Results:Compared with participants in control group,those in MI group had significant higher serum CRP,IL-6,cTnⅠ and CK-MB,and significant lower LVEF(P＜0.001 all).Serum CRP,IL-6,cTnⅠ and CK-MB levels sig-nificantly increased,and LVEF significant decreased in the order of mild group,moderate group and severe group(P＜0.01 all).Pearson/Spearman correlation analysis showed that serum CRP and IL-6 levels were positively cor-related with Gensini score,cTnⅠ,and CK-MB levels(r=0.496～0.646,P＜0.001all),and negatively correlated with LVEF(r=-0.530,-0.572,P＜0.001 all)in MI patients.ROC curve showed that the area under the curve(AUC)of CRP combined IL-6 diagnosing MI was 0.856(95％CI 0.802～0.900),which was significantly higher than those of CRP(AUC=0.770,95％CI 0.708～0.824)and IL-6(AUC=0.793,95％CI 0.733～0.845)alone(Z=3.295,2.877,P＜0.01 all).Conclusion:Serum CRP and IL-6 levels rise in MI patients,and they are closely associated with increased severity of coronary artery disease and reduced cardiac function.

Protein-protein interactions play an extremely important role in the biochemical functions of cells,and in-depth analysis of protein interactions is the key to understanding cellular life activities.In this study,we systematically mined the interacting proteins of Golgi protein 73(GP73)using classical immunoprecipitation combined with mass spectrometry,and sought to further analyze the molecular func-tion of GP73.Hepatocellular carcinoma cell line HepG2 was selected,and a stable cell line overexpress-ing GP73-3Flag was constructed using lentiviral infection technology.A total of 78 high-confidence GP73 interacting proteins were identified by immunoprecipitation coupled with mass spectrometry.Bioinformat-ics analyses suggested that GP73 interacted with nearly 40 cytosolic proteins and participated in the bio-logical processes of RNA transport,splicing,and translation.Further immunofluorescence and cytosolic protein isolation experiments confirmed the cytosolic localization of GP73 in a variety of tumor cells.Based on the 78 interacting proteins,we further screened protein interaction networks related to mRNA splicing and verified the existence of interactions between GP73 and seven proteins,including HNRN-PH3,SMN1,RBM14,andNCBP1,by co-immunoprecipitation experiments.In addition,minigene spli-cing assay results indicated that GP73 inhibited the splicing efficiency of pre-mRNA by cells.This study contributes to the expansion of knowledge regarding the function of GP73 and aids in elucidating its criti-cal role in cell biology and its potential association with diseases.