ObjectiveTo observe the effects of Yiqi Huoxue Jiedu formula（YHJF） on immune cell exhaustion in the spleen of septic mice and to explore and validate its potential intervention targets. MethodsMice were randomly divided into the sham-operated， model， low-dose YHJF（4.1 g·kg^-1）， and high-dose YHJF（8.2 g·kg^-1） groups. Except for the sham-operated group， a cecal ligation and puncture（CLP） procedure was performed to establish a mouse sepsis model. The treatment groups received oral administration of the corresponding doses， while the sham-operated and model groups received an equal volume of physiological saline. After the intervention， the 7-day survival rate of each group was recorded， and spleen samples were collected 72 h post-intervention， and the spleen index was calculated. Terminal deoxynucleotidyl transferase deoxyuridine triphosphate（dUTP） nick end labeling（TUNEL） staining was used to detect apoptosis in spleen cells. Enzyme-linked immunosorbent assay（ELISA） was performed to measure the levels of interleukin（IL）-4 and IL-10 in the serum. Transcriptomics and metabolomics were used to screen for differentially expressed genes（DEGs） and differential metabolites in the spleen， followed by bioinformatics analysis to identify key targets. Real-time quantitative polymerase chain reaction（Real-time PCR）， flow cytometry， and multiplex immunofluorescence were used to verify the expressions of key genes and proteins. ResultsThe high-dose YHJF group significantly improved the 7-day survival rate of septic mice（P0.05）. Compared with the sham-operated group， the model group showed a significant increase in apoptosis of spleen cells and a decrease in the spleen index at 72 h post-modeling， with markedly elevated peripheral serum IL-4 and IL-10 levels（P0.01）. Compared with the model group， the high-dose YHJF group showed a reduction in apoptosis of spleen cells， an increase in the spleen index， and a significant decrease in peripheral serum IL-4 and IL-10 levels（P0.05）. Spleen transcriptomics identified 255 DEGs between groups， potentially serving as intervention targets for YHJF. Gene Ontology（GO） enrichment analysis revealed that DEGs were mainly involved in biological processes such as natural killer（NK） cell-mediated positive immune regulation， cell killing， cytokine production， positive regulation of innate immune cells， and interferon production. Kyoto Encyclopedia of Genes and Genomes（KEGG） pathway enrichment analysis showed that DEGs were mainly involved in cytokine-cytokine receptor interactions， viral protein interactions with cytokines and cytokine receptors， chemokine signaling pathway， and nuclear transcription factor-κB（NF-κB） signaling pathway. Protein-protein interaction（PPI） network analysis identified CD160， granzyme B（GZMB）， and chemokine ligand 4（CCL4） as key targets for YHJF in treating sepsis. Metabolomics identified 46 differential metabolites that were significantly reversed by YHJF intervention， and combined transcriptomics and metabolomics analysis identified 17 differential metabolites closely related to CD160. Pathway enrichment revealed that these metabolites were mainly involved in glycerophospholipid metabolism， arachidonic acid metabolism， glycosylphosphatidylinositol（GPI） anchor biosynthesis， linoleic acid metabolism， and α-linolenic acid metabolism pathways. Verification results showed that， compared with the sham-operated group， the model group exhibited significantly elevated CD160 mRNA expression level in the spleen， along with markedly decreased CCL4 and GZMB mRNA expression， and had a significant increase in CD160 expression on the surface of natural killer T（NKT） cells in the spleen（P0.01）. Compared with the model group， the high-dose YHJF group had a significant decrease in CD160 mRNA expression in the spleen， a significant increase in CCL4 and GZMB mRNA expressions. Further flow cytometry and immunofluorescence revealed that compared with the sham-operated group， CD160 expression on the surface of splenic NKT cells in the model group was significantly increased（P0.01）， while high-dose YHJF intervention significantly reduced CD160 expression（P0.01）. ConclusionYHJF may alleviate NKT cell exhaustion in sepsis by downregulating the expression of the negative co-stimulatory molecule CD160， and this regulatory effect is closely related to fatty acid metabolism pathways. This study provides new insights and targets for further exploration of strengthening vital Qi and detoxifying strategy to improve immune cell exhaustion in acute deficiency syndrome of sepsis.

ObjectiveTo observe the effects of Yiqi Huoxue Jiedu formula（YHJF） on immune cell exhaustion in the spleen of septic mice and to explore and validate its potential intervention targets. MethodsMice were randomly divided into the sham-operated， model， low-dose YHJF（4.1 g·kg^-1）， and high-dose YHJF（8.2 g·kg^-1） groups. Except for the sham-operated group， a cecal ligation and puncture（CLP） procedure was performed to establish a mouse sepsis model. The treatment groups received oral administration of the corresponding doses， while the sham-operated and model groups received an equal volume of physiological saline. After the intervention， the 7-day survival rate of each group was recorded， and spleen samples were collected 72 h post-intervention， and the spleen index was calculated. Terminal deoxynucleotidyl transferase deoxyuridine triphosphate（dUTP） nick end labeling（TUNEL） staining was used to detect apoptosis in spleen cells. Enzyme-linked immunosorbent assay（ELISA） was performed to measure the levels of interleukin（IL）-4 and IL-10 in the serum. Transcriptomics and metabolomics were used to screen for differentially expressed genes（DEGs） and differential metabolites in the spleen， followed by bioinformatics analysis to identify key targets. Real-time quantitative polymerase chain reaction（Real-time PCR）， flow cytometry， and multiplex immunofluorescence were used to verify the expressions of key genes and proteins. ResultsThe high-dose YHJF group significantly improved the 7-day survival rate of septic mice（P0.05）. Compared with the sham-operated group， the model group showed a significant increase in apoptosis of spleen cells and a decrease in the spleen index at 72 h post-modeling， with markedly elevated peripheral serum IL-4 and IL-10 levels（P0.01）. Compared with the model group， the high-dose YHJF group showed a reduction in apoptosis of spleen cells， an increase in the spleen index， and a significant decrease in peripheral serum IL-4 and IL-10 levels（P0.05）. Spleen transcriptomics identified 255 DEGs between groups， potentially serving as intervention targets for YHJF. Gene Ontology（GO） enrichment analysis revealed that DEGs were mainly involved in biological processes such as natural killer（NK） cell-mediated positive immune regulation， cell killing， cytokine production， positive regulation of innate immune cells， and interferon production. Kyoto Encyclopedia of Genes and Genomes（KEGG） pathway enrichment analysis showed that DEGs were mainly involved in cytokine-cytokine receptor interactions， viral protein interactions with cytokines and cytokine receptors， chemokine signaling pathway， and nuclear transcription factor-κB（NF-κB） signaling pathway. Protein-protein interaction（PPI） network analysis identified CD160， granzyme B（GZMB）， and chemokine ligand 4（CCL4） as key targets for YHJF in treating sepsis. Metabolomics identified 46 differential metabolites that were significantly reversed by YHJF intervention， and combined transcriptomics and metabolomics analysis identified 17 differential metabolites closely related to CD160. Pathway enrichment revealed that these metabolites were mainly involved in glycerophospholipid metabolism， arachidonic acid metabolism， glycosylphosphatidylinositol（GPI） anchor biosynthesis， linoleic acid metabolism， and α-linolenic acid metabolism pathways. Verification results showed that， compared with the sham-operated group， the model group exhibited significantly elevated CD160 mRNA expression level in the spleen， along with markedly decreased CCL4 and GZMB mRNA expression， and had a significant increase in CD160 expression on the surface of natural killer T（NKT） cells in the spleen（P0.01）. Compared with the model group， the high-dose YHJF group had a significant decrease in CD160 mRNA expression in the spleen， a significant increase in CCL4 and GZMB mRNA expressions. Further flow cytometry and immunofluorescence revealed that compared with the sham-operated group， CD160 expression on the surface of splenic NKT cells in the model group was significantly increased（P0.01）， while high-dose YHJF intervention significantly reduced CD160 expression（P0.01）. ConclusionYHJF may alleviate NKT cell exhaustion in sepsis by downregulating the expression of the negative co-stimulatory molecule CD160， and this regulatory effect is closely related to fatty acid metabolism pathways. This study provides new insights and targets for further exploration of strengthening vital Qi and detoxifying strategy to improve immune cell exhaustion in acute deficiency syndrome of sepsis.

Background Pyrethroid pesticides (PYRs) can cross the placental barrier to cause intrauterine fetal exposure, which may lead to developmental immunotoxicity (DIT). However, the specific effect of maternal PYR exposure during pregnancy on the cellular immune function of 1-year-old children remains unclear. Objective To explore the effect of PYRs exposure throughout the entire pregnancy on peripheral blood lymphocytes in 1-year-old children and potential sensitive window period of PYRs exposure. Methods A birth cohort was established by enrolling pregnant women in their first trimester and following them and their infants until one year of age. Ultra-high performance liquid chromatography-tandem mass spectrometry was used to detect the levels of PYRs metabolites, including 3-phenoxybenzoic acid (3PBA), 4-fluoro-3-phenoxybenzoic acid (4F3PBA), and cis-3-(2,2-dichlorovinyl)-2,2- dimethylcyclopropane carboxylic acid (cis-DBCA), in the urine of pregnant women during the first trimester (gestational weeks 6-12), the second trimester (gestational weeks 21-24), and the third trimester (gestational weeks 33-36). Peripheral blood leukocyte and lymphocyte counts were measured in children at 12 months of age using the Coulter principle combined with flow cytometry. Exposure levels of PYRs metabolites in each trimester were divided into low, moderate, and high exposure groups based on the 25th (P₂₅) and 75th (P₇₅) percentiles. Meanwhile, participants were classified as having repeated high or low exposure if their metabolite levels were > P₇₅ or <P₂₅ in at least two trimesters, respectively, while all others were categorized as having repeated moderate exposure. Generalized linear models were used to analyze the associations between trimester-specific and repeated PYRs metabolite exposure levels and the peripheral blood white blood cell (WBC) and lymphocyte counts in children aged 1 year. Results A total of 336 mother-child pairs were included in this study. For the pregnant women, the total detection rates of maternal urinary 3PBA, 4F3PBA, and cis-DBCA across the three trimesters of pregnancy were 80.5%, 100.0%, and 81.3%, respectively; and median creatinine-corrected concentrations were 0.24, 0.36, and 0.42 μg·g⁻¹, respectively. In children aged 1 year, the mean WBC and lymphocyte counts in peripheral blood were (8.9±2.0)×10⁹·L⁻¹ and (5.7±1.6)×10⁹·L⁻¹, respectively. The results of the generalized linear model analysis indicated that compared to the low exposure group, the high cis-DBCA exposure group during the third trimester of pregnancy had significantly lower peripheral blood WBC count (β=−0.87, 95%CI: −1.51, −0.23) and lymphocyte count (β=−0.64, 95%CI: −1.15, −0.13); and the repeated high-exposure group of cis-DBCA had significantly lower peripheral blood WBC count (β=−1.34, 95%CI: −2.34, −0.34) and lymphocyte count (β=−0.80, 95%CI: −1.60, −0.01) than the repeated low exposure group. Similarly, the repeated moderate-exposure group of cis-DBCA had a significantly lower peripheral blood WBC count (β=−0.83, 95%CI: −1.59, −0.07) than the repeated low exposure group. Conclusion High maternal exposure to PYRs with cis-DBCA as the major metabolite exposure is associated with decreased peripheral leukocyte and lymphocyte counts in children aged 1 year, and repeated high-level exposure throughout gestation appears to exacerbate DIT in offspring. The third trimester of pregnancy maybe a sensitive window for children's DIT induced by exposure to PYRs during pregnancy.

With the main pathological features of glomerulosclerosis and interstitial fibrosis， renal fibrosis is a key pathological process causing chronic kidney disease to progress to end-stage disease. As a cellular autophagic process， mitochondrial autophagy plays a crucial role in maintaining mitochondrial mass and functional stability. Mitochondrial dysfunction is considered to be one of the key factors driving the progression of fibrosis. Phosphatase and tension protein homologue （PTEN） induce various signalling pathways such as putative kinase 1/parkin， Nip3-like protein X/Bcl-2 interacting protein 3， and FUN14 structural domain-containing protein 1 to activate mitochondrial autophagy to participate in the regulation of fibrogenic factors， amelioration of oxidative stress， and inhibition of inflammatory response and apoptosis， which in turn effectively slows down the progression of renal fibrosis. Studies have shown that traditional Chinese medicine monomers and compound preparations， including phenolics， terpenoids， ketones， and alkaloids， can regulate mitochondrial autophagy-related signalling pathways and achieve significant clinical efficacy in intervening in the progression of renal fibrosis for the treatment of chronic kidney disease. This paper summarized the mechanism of mitochondrial autophagy and the research progress of traditional Chinese medicine intervention in renal fibrosis to provide new ideas for the study of the mechanism of traditional Chinese medicine in treating renal fibrosis.

With the main pathological features of glomerulosclerosis and interstitial fibrosis， renal fibrosis is a key pathological process causing chronic kidney disease to progress to end-stage disease. As a cellular autophagic process， mitochondrial autophagy plays a crucial role in maintaining mitochondrial mass and functional stability. Mitochondrial dysfunction is considered to be one of the key factors driving the progression of fibrosis. Phosphatase and tension protein homologue （PTEN） induce various signalling pathways such as putative kinase 1/parkin， Nip3-like protein X/Bcl-2 interacting protein 3， and FUN14 structural domain-containing protein 1 to activate mitochondrial autophagy to participate in the regulation of fibrogenic factors， amelioration of oxidative stress， and inhibition of inflammatory response and apoptosis， which in turn effectively slows down the progression of renal fibrosis. Studies have shown that traditional Chinese medicine monomers and compound preparations， including phenolics， terpenoids， ketones， and alkaloids， can regulate mitochondrial autophagy-related signalling pathways and achieve significant clinical efficacy in intervening in the progression of renal fibrosis for the treatment of chronic kidney disease. This paper summarized the mechanism of mitochondrial autophagy and the research progress of traditional Chinese medicine intervention in renal fibrosis to provide new ideas for the study of the mechanism of traditional Chinese medicine in treating renal fibrosis.

Objective:To carry out a scoping review of studies on prehabilitation in kidney transplant patients.Methods:Databases such as China National Knowledge Infrastructure, VIP, Wanfang Data, China Biology Medicine disc, PubMed, Web of Science, Cochrane Library and Embase were searched according to the research methodology of the scoping review. The search period was from database establishment to August 14, 2024. Two researchers screened, summarized and analyzed the included literature.Results:A total of 11 papers were included. Intervention components involved unimodal prehabilitation and multimodal prehabilitation that incorporated exercise, nutrition, and psychological interventions. Forms of intervention included aerobic, resistance, flexibility exercises, respiratory function exercises, nutritional support, mindfulness-based stress reduction, psychoeducation, and cognitive therapy. Outcome indicators consisted of physical indicators, psychological indicators, quality of life, postoperative and feasibility indicators. Prehabilitation had positive impacts on cardiorespiratory fitness, physical fitness, physical activity, pain, quality of life, anxiety and depression, and short-term postoperative outcomes in kidney transplant patients.Conclusions:Prehabilitation interventions in kidney transplant patients are comprehensive, individualized, and have short-term positive outcomes. Future researchers should develop individualized multimodal prehabilitation intervention programs based on theoretical models to explore the long-term effects of prehabilitation, and should incorporate comprehensive evaluation indicators to explore the healthcare value and expandability factors of prehabilitation.

Objective:To analyze the selection of internal fixation methods, surgical outcomes, and complications in patients with Neurofibromatosis Type 1 (NF1) accompanied by dystrophic lumbosacral deformities, and to evaluate the indications for pelvic fixation.Methods:A retrospective analysis was conducted on 21 patients with NF1 and associated dystrophic lumbosacral malformations (L 4 to sacrum) who underwent spinal deformity correction surgery at Nanjing Drum Tower Hospital from January 2009 to November 2022. The cohort included 11 males and 10 females, with a mean surgical age of 15.4±4.7 years (range, 7-24 years). Patients were divided into two groups based on whether pelvic fixation was performed: 10 patients in the non-pelvic fixation group (NP group) and 11 in the pelvic fixation group (P group), where fixation involved second sacral alar-iliac (S 2AI) screws or iliac screws. Radiographic parameters, including the Cobb angle of the lumbosacral fractional curve, main curve, and focal kyphosis, were compared preoperatively, postoperatively, and at the last follow-up. Results:The NP group had a significantly lower mean age (13.2±4.9 years) compared to the P group (17.5±3.5 years; t=2.287, P=0.034). Spinal instability (rotational subluxation or spondylolisthesis) due to dystrophic changes was observed in 2 patients in the NP group and 8 in the P group, a statistically significant difference (χ 2=5.838, P=0.030). In the P group, five patients underwent unilateral fixation and six underwent bilateral fixation. Implant types included 2 cases with iliac screws, 1 case with iliac screws plus S 2AI, and 8 cases with S 2AI screws alone. The utilization rate of hooks was significantly higher in the NP group (12.6%±11.5%) compared to the P group (3.5%±6.9%; t=2.230, P=0.038). The preoperative Cobb angle of the lumbosacral fractional curve was significantly smaller in the NP group (13.8°±9.0°) than in the P group (25.5°±13.9°; t=2.228, P=0.039). Postoperatively, the angles were corrected to 6.3°±6.1° and 6.4°±5.3°, respectively ( t=0.901, P=0.969), with correction rates of 57.3%±13.6% and 74.1%±17.8% ( t=2.369, P=0.029). At final follow-up, the angles remained stable (6.6°±6.6° vs. 6.3°±4.8°; t=0.116, P=0.909). For the main curve, preoperative Cobb angles were 52.5°±15.1° (NP) and 61.1°±16.9° (P; t=1.200, P=0.246), corrected to 31.3°±13.8° and 28.0°±8.4°, respectively ( t=0.646, P=0.526). Correction rates were 41.3%±13.0% in the NP group and 53.2%±11.6% in the P group ( t=2.206, P=0.037). At the final follow-up, these values were 32.4°±14.2° and 31.7°±10.3° ( t=0.133, P=0.896). Focal kyphosis, seen in 9 patients, was corrected from 19.7°±10.9° preoperatively to -13.6°±9.5° postoperatively, and remained at -14.1°±9.6° at the final follow-up ( F=33.547, P<0.001). Multi-rod systems were used in 6 cases (NP group) and 7 cases (P group), with no significant difference (χ 2=0.153, P=0.926). Two patients in the NP group developed coronal decompensation three years postoperatively, and one required revision surgery. In the P group, rod breakage occurred in 3 patients, two of whom underwent revision. Conclusions:Dystrophic rotational subluxation or spondylolisthesis of the lumbosacral spine is a primary indication for pelvic fixation in patients with NF1-associated deformities. However, complications related to internal fixation remain common. The combined use of a multi-rod screw-hook hybrid system, particularly when extending across the lumbosacral region, may reduce the risk of instrumentation failure.

The aim of this study is to identify the cause of death of a South China tiger cub at the Meihuashan breeding institute of Fujian Province.Pathogenic bacteria were isolated and cultured from liver,spleen,lung and other tissue samples of the dead South China tiger aseptically.The iso-lated bacteria were identified through morphological observation,biochemical characterization,sequence analysis of housekeeping gene gyrB,virulence gene detection,animal pathogenicity test and drug sensitivity test.A pathogenic Aeromonas hydrophila strain,designated FJ/Tiger-201809 was successfully isolated from the trachea of dead South China tiger.The nucleotide sequence ho-mology between the isolate and 11 strains of Aeromonas gyrB ranged from 91.2％to 99.1％,with the highest homology of 99.1％observed with Aeromonas hydrophila(AF208251.1).Genetic evo-lution analysis showed that the isolated strain FJ/Tiger-201809 was in the same evolutionary branch as other reference strains of Aeromonas hydrophila and was closely related.The pathoge-nicity test in mice showed artificial infection of mice with the strain resulted in varying degrees of lesions in several organs of the mice,and the median lethal dose(LD50)was 1 × 107.8 CFU/mL.Virulence gene test results showed that the isolate FJ/Tiger-201809 carried two virulence genes,aer and act.The results of drug sensitivity test showed that FJ/Tiger-201809 was highly sensitive to enrofloxacin and ampicillin among 18 commonly used antibiotics,relatively sensitive to penicil-lin G and doxycycline,and resistant to the other 14 antibiotics.In conclusion,this study isolated and identified a strain of Aeromonas hydrophila from a dead South China tiger with multiple drug resistance and strong pathogenicity,which provided an important reference for the prevention and control of bacterial diseases in South China tiger.

OBJECTIVE To investigate the effects and underlying mechanisms of Yiqi Huoxue Decoction(YQHX)on mitochon-drial midzone division and peripheral fission in myocardial tissue after myocardial infarction(MI).METHODS A total of 48 male SPF-grade C57BL/6N mice were randomly divided into a sham-operated group(Sham,n=12)and a left anterior descending coronary ar-tery ligation MI model(n=36).After MI surgery,mice deemed to have successfully developed the model were randomly divided into a model group(MI,n=12),a YQHX group(n=12),and an empagliflozin group(EMPA,n=12)based on echocardiographic results.Four weeks after infarction,cardiac function and structural changes were comprehensively evaluated using echocardiography imaging,serum myocardial injury biomarkers,and hematoxylin-eosin(HE)staining.Transmission electron microscopy(TEM)was employed to observe mitochondrial ultrastructural,morphological,and quantitative changes at the peri-infarct zone.Myocardial mitochondria and cytoplas-mic fractions were isolated from myocardial tissue using a mitochondrial extraction kit,and the spatial expression changes of mitochon-drial fission-related proteins in both mitochondria and cytoplasm of the peri-infarct myocardium were analyzed by Western blot.These proteins included dynamin-related protein 1(Drp1),its phosphorylated form at serine 616(P-Drp1-Ser616),mitochondrial fission fac-tor(MFF),and mitochondrial fission protein 1(Fis1).RESULTS Compared with the MI group,mice in the YQHX group exhibited sig-nificantly increased left ventricular ejection fraction(LVEF)and left ventricular fractional shortening(LVFS)(P<0.000 1),as well as decreased left ventricular internal dimension-diastole(LVIDd)and left ventricular end-systolic diameter(LVIDs)(P<0.05,P<0.01),suggesting improved cardiac function.Additionally,serum levels of lactate dehydrogenase(LDH)and creatine kinase-MB(CK-MB)were significantly reduced in the YQHX group(P<0.05,P<0.001),indicating cardio-protective effects of YQHX against ischemic in-jury.HE staining showed that YQHX improved cellular morphology,suggesting structural improvement.TEM showed that YQHX sig-nificantly improved mitochondrial swelling and reduced mitochondrial fragmentation in the marginal zone of myocardial infarction,thereby preserving mitochondrial ultrastructure.Furthermore,Western blot showed that YQHX treatment significantly downregulated P-Drp1-Ser616 expression(P<0.05)in the cytoplasm.Interestingly,YQHX treatment significantly downregulated mitochondrial Fis1 expression(P<0.05),thereby inhibiting peripheral mitochondrial fission.Meanwhile,YQHX treatment significantly increased MFF ex-pression in mitochondria(P<0.01),which may promote mitochondrial midzone fission.CONCLUSION YQHX improves cardiac structure and function after MI,potentially by promoting myocardial mitochondrial midzone fission and inhibiting mitochondrial periph-eral fission in ischemic cardiomyocytes.

AIM:To investigate the role of SET and MYND domain-containing protein 3(SMYD3)-mediated histone H3 lysine 4 trimethylation(H3K4me3)dysregulation in pulmonary vascular remodeling in a rat model of pulmo-nary arterial hypertension associated with atrial septal defect(PAH-ASD).METHODS:The PAH-ASD rat model was created using transseptal puncture and radiofrequency ablation techniques.The rats were randomly assigned to 5 groups:normal,sham,PAH-ASD,PAH-ASD+vehicle(Veh),and PAH-ASD+BCI-121(SMYD3 inhibitor).Four weeks after modeling,lung tissues and pulmonary vessels were harvested for subsequent analysis.Western blot analysis was conducted to evaluate the protein levels of SMYD3,H3K4me3,transforming growth faction-β1(TGF-β1),and collagen type Ⅲ(Col Ⅲ).The mRNA expression of TGF-β1 was quantified using RT-qPCR.Histological assessment of pulmonary vascu-lar fibrosis,vascular wall thickness and smooth muscle proliferation was executed through Masson's trichrome and HE staining.Co-immunoprecipitation(Co-IP)assay was performed to investigate the interactions among SMYD3,H3K4me3,and TGF-β1.Hemodynamic parameters,including mean pulmonary artery pressure(mPAP),were quantified using a computerized physiological signal acquisition system.RESULTS:The Western blot analysis indicated a significant in-crease in the protein levels of SMYD3,TGF-β1,Col Ⅲ,and H3K4me3 in the PAH-ASD group compared with the sham group(P<0.05).RT-qPCR corroborated the elevation of TGF-β1 mRNA expression in the PAH-ASD group(P<0.05).Furthermore,Masson's trichrome and HE staining techniques revealed more pronounced pulmonary vascular fibrosis,an augmented vascular wall area,and an elevated vascular area index within the PAH-ASD group(P<0.05).Additionally,the right ventricular hypertrophy index(RVHI)and mPAP were significantly elevated in the PAH-ASD group(P<0.05).The administration of BCI-121 resulted in a significant reduction of SMYD3,TGF-β1,Col Ⅲ,and H3K4me3 levels(P<0.05),while also mitigating pulmonary vascular fibrosis,RVHI,mPAP,pulmonary vascular area,and area index(P<0.05).Co-IP confirmed direct interactions among SMYD3,H3K4me3,and TGF-β1.CONCLUSION:Histone methyl-transferase SMYD3-mediated histone H3K4me3 modification plays a role in the pulmonary vascular remodeling of PAH-ASD model rats.The underlying mechanism may involve the regulation of pulmonary vascular proliferation and fibrosis me-diated by the overexpression of TGF-β1 and Col Ⅲ.