BACKGROUND:Previous studies by the research group have shown that core proteoglycan in Cornus Cervi Col la can enter the bone,promote the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells,and has a good repair effect on steroid-induced osteonecrosis of the femoral head.OBJECTIVE:To investigate the therapeutic effect and potential mechanism of Cornus Cervi Colla on steroid-induced osteonecrosis of the femoral head in rats by fecal non-targeted fecal metabolomics.METHODS:Thirty SD rats were randomly divided into three groups using a random number table method:the control group(n=10)was injected with normal saline into the right gluteal muscle(injected on the first 3 days of each week for 3 consecutive weeks),and was given pure water gavage(once a day for 6 consecutive weeks).The model group(n=10)was injected with methylprednisolone sodium succinate into the right gluteal muscle(injected on the first 3 days of each week for 3 consecutive weeks)to establish a steroid-induced osteonecrosis of the femoral head model,and was given pure water gavage(once a day for 6 consecutive weeks).The Cornus Cervi Co I la group(n=10)was also established with a steroid-induced osteonecrosis of the femoral head model,and was given Cornus Cervi Col la gavage(once a day for 6 consecutive weeks).After gavage,cecal feces and femoral heads were collected for fecal metabolomics analysis and bone tissue Micro-CT and hematoxylin-eosin staining,respectively.RESULTS AND CONCLUSION:(1)Metabolomics analysis results showed that there were 233 differential metabolites between the Cornus Cervi Col la and model groups,with 65 significantly differing and clearly annotated metabolites.Lipid and amino acid metabolites were significantly increased,with bile acids,sulfated steroids,ephedrine,hypoxanthine,betaine,L-carnitine,B-mouse bile acid,cytidine,4-pyridoxic acid,taurine,N-acetyl-d-glucosamine,and butyric acid being the most impacted(variable weight value VIP＞5).The metabolic pathways of taurine and hypotaurine were crucial in the metabolic regulatory network(pathway impact=0.428 57).(2)Micro-CT scanning results of bone tissue showed that the femoral heads of rats in the model group and the Cornus Cervi Col la group had different degrees of damage;the femoral head contour was irregular;the trabeculae in the subchondral bone of the femoral head were missing and disordered,and some cystic structures were visible.Compared with the model group,the degree of trabecular damage in the rats of the Cornus Cervi Colla group was milder.Hematoxylin-eosin staining results showed that the trabeculae in the subchondral bone of the femoral heads of rats in the model group and the Cornus Cervi Colla group were sparse or interrupted,and the empty bone lacuna rate and adipocyte invasion were increased.Compared with the model group,the empty bone lacuna rate and adipocyte invasion in the subchondral bone of the femoral heads of rats in the Cornus Cervi Colla group were reduced.(3)These results conclude that Cornus Cervi Colla potentially mitigates steroid-induced osteonecrosis of the femoral head through the metabolic processes involving taurine and associated pathways.

Objective To evaluate the efficacy of uterine artery embolization(UAE)for the treatment of adenomyosis(AM)and to discuss the factors predicting efficacy.Methods The clinical data of 44 patients with AM,who received UAE at The Second Affiliated Hospital of Soochow University from January 2020 to August 2022,were retrospectively analyzed.Based on the MRI findings,serum CA125 levels and follow-up dysmenorrhea scores,the efficacy of UAE and the factors predicting efficacy were analyzed.Results A single UAE treatment was performed in all 44 patients with AM.Follow-up check with MRI at 12 months after treatment showed that the mean uterine volume decreased from preoperative(299.60±182.42)cm3 to postoperative(173.14±104.00)cm3,with a volume reduction of 36.64％(P＜0.05).The dysmenorrhea score decreased from preoperative(7.70±2.60)points to postoperative(2.20+2.37)points,with a relief rate of 88.64％(P＜0.05),and no severe adverse reactions occurred.Enhanced MRI demonstrated that in 30 patients(68.18％)the AM lesions presented as complete necrosis foci.In the patients whose preoperative lesions were completely necrotic,the mean preoperative serum CA125 level was(101.97±60.30)U/mL,the mean ADC value was(1.012+0.271)mm2/s,which were obviously lower than those in the patients whose preoperative lesions were incompletely necrotic(P＜0.05).The mean T2 signal ratio(T2SR)value in the patients whose preoperative lesions were completely necrotic was(0.582±0.198),which was significantly higher than that in the patients whose preoperative lesions were incompletely necrotic(P＜0.05).The analysis of receiver operating characteristic(ROC)curve showed that the preoperative area under the curve(AUC),sensitivity,and specificity for preoperative CA125 were 0.844,60％and 80％respectively;the AUC,sensitivity,and specificity for preoperative ADC were 0.760,80％and 65％respectively;and the AUC,sensitivity,and specificity for preoperative T2SR were 0.760,80％and 70％respectively.ADC＜1.116 × 10-3 mm2/s,T2SR＞0.479,and CA125＜109.10 U/mL could be used as the reliable predictive factors for the efficacy of UAE treatment for AM.Conclusion UAE can effectively alleviate dysmenorrhea symptoms in patients with AM,and it is clinically safe and effective.ADC,T2SR,and CA125 can be used as the reliable predictive factors for the efficacy of UAE treatment for AM,which are helpful in predicting the lesion response and selecting the reasonable therapeutic options for patients.

BACKGROUND:Osteonecrosis is an orthopedic disease that severely limits joint function,with complex pathogenesis involving multiple risk factors.Cathepsins,as a class of enzymes that play a key role in bone metabolism,are closely related to the proliferation,differentiation of bone cells,and remodeling of the bone matrix.However,previous studies have mostly focused on descriptive analyses,lacking direct evidence of causal relationships.OBJECTIVE:To clarify the potential causal relationship between cathepsins and osteonecrosis and to explore their possible mechanisms by analyzing large-scale sample data from the FinnGen database.METHODS:We obtained osteonecrosis-related data from the FinnGen database,including R9(a total of 359 399 samples:1 385 cases and 358 014 controls)and R10 versions(a total of 392 580 samples:1 543 cases and 391 037 controls).Single nucleotide polymorphisms associated with nine cathepsins(cathepsin B,E,F,G,H,O,S,L2,and Z)were acquired from a previous study(3 301 individuals).Univariate Mendelian randomization,reverse univariate Mendelian randomization,and multivariate Mendelian randomization analyses were conducted using the inverse variance weighted method,MR-Egger method,weighted median method,simple mode method,and weighted mode method.Initially,Mendelian randomization analysis was performed using osteonecrosis data from R9.Additionally,sensitivity analyses were conducted using Cochran's Q test,MR-Egger intercept,MR-PRESSO global test,and leave-one-out analysis to check for horizontal pleiotropy and heterogeneity.Subsequently,a validation analysis study was carried out on the R10 dataset,and a meta-analysis was conducted to combine the two datasets to explore the joint effect.RESULTS AND CONCLUSION:Univariate Mendelian randomization analysis results showed that higher levels of cathepsin B were significantly associated with a reduced risk of osteonecrosis(inverse variance weighted:odds ratio(OR)=0.865,95％confidence interval(CI):0.762-0.982,P=0.025),and no reverse causal relationship was found between the nine cathepsins and osteonecrosis(P＞0.05).These associations were validated by meta-analysis.Multivariate analysis,using the nine cathepsins as covariates,revealed a reverse causal relationship between the levels of cathepsin Band the risk of osteonecrosis(inverse variance weighted:OR=0.8710,95％CI:0.761-0.997,P=0.045),consistent with the results before adjustment.Sensitivity analyses based on heterogeneity and horizontal pleiotropy suggested that the results were relatively robust.This study suggests that there is a causal relationship between high levels of cathepsin B and the reduced risk of osteonecrosis,and it may serve as a biomarker for osteonecrosis,providing new directions and insights for the diagnosis and treatment of osteonecrosis.Although this study is based on data analysis of European populations,these findings have important implications for Chinese biomedical research,especially in understanding disease mechanisms,developing biomarkers,and formulating treatment strategies.They also encourage similar studies conducted on Chinese populations to explore the impact of racial and genetic background differences on the occurrence of osteonecrosis.

Objective To evaluate pulmonary vascular remodeling,right ventricular function,intestinal barrier integrity,and inflammatory factor expression in rat models of pulmonary hypertension(PH)induced by normobaric hypoxia(NH)and hypobaric hypoxia(HH).We also aimed to compare modeling method and establish an experimental basis for understanding the pathogenesis of PH and for developing appropriate treatment strategies.Methods From June 2024 to December 2024,eighteen 6-week-old male SPF Sprague-Dawley rats were assigned randomly to three groups:normobaric normoxia(Control),NH,and HH groups.Mean pulmonary artery pressure(mPAP)was measured by right heart catheterization.Right ventricular function was assessed using echocardiography and right ventricular hypertrophy index(RVHI).Pulmonary vascular remodeling and intestinal mucosal barrier damage were evaluated via hematoxylin/eosin staining.Colon permeability was quantified by colon ligation followed by fluorescein isothiocyanate-dextran injection.Expression levels of inflammatory factors in lung and colon tissues were analyzed by enzyme-linked immunosorbent assays.Results Right heart function assessment revealed that mPAP was significantly increased(P＜0.05),pulmonary artery acceleration time(PAAT)was shortened,and RVHI and right ventricular free wall thickness(RVFW)were significantly elevated(P＜0.05)in rats in NH and HH groups compared with Control group.Rats in NH group demonstrated a prolonged pulmonary ejection time(PET)and reduced PAAT/PET ratio compared with HH group,indicating more pronounced right heart dysfunction.Pulmonary vascular morphology demonstrated that percentage of medial area percentage(MA％)and percentage of wall thickness percentage(WT％)of pulmonary vessels were significantly higher in NH and HH groups compared with Control group(P＜0.05).Moreover,MA％was markedly increased in the NH group relative to the HH group(P＜0.05),suggesting more severe pulmonary vascular remodeling in NH group.Regarding intestinal injury,rats in NH and HH groups exhibited shorter colon length,increased mucosal damage,and significantly increased permeability compared with Control group(P＜0.05),while rats in HH group showed more prominent inflammatory cell infiltration compared with NH group,confirming intestinal mucosal barrier damage in both groups.In terms of inflammation,expression levels of interleukin(IL)6,IL1β,and IL 17a were significantly elevated in lung and colon tissues from rats in NH and HH groups compared with Control group(P＜0.05).Notably,expression levels of IL6 and IL1 β in lung tissue and IL17a in colon tissue were significantly higher in NH group compared with HH group(P＜0.05),while IL6 expression in colon tissue was relatively lower(P＜0.05),indicating local inflammation in lung and colon tissues in both groups.Conclusions There are phenotypic differences between PH rat models induced by NH and HH,with respect to pulmonary vascular remodeling,right heart function,intestinal mucosal barrier injury,and the expression of inflammatory factors in lung and intestinal tissues.These result demonstrate that air pressure contributes to the pathogenesis and progression of PH.Different air pressures may affect the development of PH via distinct mechanisms,thereby offering critical insights into the pathological changes of PH,potential therapeutic strategies to mitigate disease progression,and the elucidation of inflammatory mechanisms underlying PH based on the lung-intestine axis.

Objective To evaluate pulmonary vascular remodeling,right ventricular function,intestinal barrier integrity,and inflammatory factor expression in rat models of pulmonary hypertension(PH)induced by normobaric hypoxia(NH)and hypobaric hypoxia(HH).We also aimed to compare modeling method and establish an experimental basis for understanding the pathogenesis of PH and for developing appropriate treatment strategies.Methods From June 2024 to December 2024,eighteen 6-week-old male SPF Sprague-Dawley rats were assigned randomly to three groups:normobaric normoxia(Control),NH,and HH groups.Mean pulmonary artery pressure(mPAP)was measured by right heart catheterization.Right ventricular function was assessed using echocardiography and right ventricular hypertrophy index(RVHI).Pulmonary vascular remodeling and intestinal mucosal barrier damage were evaluated via hematoxylin/eosin staining.Colon permeability was quantified by colon ligation followed by fluorescein isothiocyanate-dextran injection.Expression levels of inflammatory factors in lung and colon tissues were analyzed by enzyme-linked immunosorbent assays.Results Right heart function assessment revealed that mPAP was significantly increased(P＜0.05),pulmonary artery acceleration time(PAAT)was shortened,and RVHI and right ventricular free wall thickness(RVFW)were significantly elevated(P＜0.05)in rats in NH and HH groups compared with Control group.Rats in NH group demonstrated a prolonged pulmonary ejection time(PET)and reduced PAAT/PET ratio compared with HH group,indicating more pronounced right heart dysfunction.Pulmonary vascular morphology demonstrated that percentage of medial area percentage(MA％)and percentage of wall thickness percentage(WT％)of pulmonary vessels were significantly higher in NH and HH groups compared with Control group(P＜0.05).Moreover,MA％was markedly increased in the NH group relative to the HH group(P＜0.05),suggesting more severe pulmonary vascular remodeling in NH group.Regarding intestinal injury,rats in NH and HH groups exhibited shorter colon length,increased mucosal damage,and significantly increased permeability compared with Control group(P＜0.05),while rats in HH group showed more prominent inflammatory cell infiltration compared with NH group,confirming intestinal mucosal barrier damage in both groups.In terms of inflammation,expression levels of interleukin(IL)6,IL1β,and IL 17a were significantly elevated in lung and colon tissues from rats in NH and HH groups compared with Control group(P＜0.05).Notably,expression levels of IL6 and IL1 β in lung tissue and IL17a in colon tissue were significantly higher in NH group compared with HH group(P＜0.05),while IL6 expression in colon tissue was relatively lower(P＜0.05),indicating local inflammation in lung and colon tissues in both groups.Conclusions There are phenotypic differences between PH rat models induced by NH and HH,with respect to pulmonary vascular remodeling,right heart function,intestinal mucosal barrier injury,and the expression of inflammatory factors in lung and intestinal tissues.These result demonstrate that air pressure contributes to the pathogenesis and progression of PH.Different air pressures may affect the development of PH via distinct mechanisms,thereby offering critical insights into the pathological changes of PH,potential therapeutic strategies to mitigate disease progression,and the elucidation of inflammatory mechanisms underlying PH based on the lung-intestine axis.

BACKGROUND:Previous studies by the research group have shown that core proteoglycan in Cornus Cervi Col la can enter the bone,promote the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells,and has a good repair effect on steroid-induced osteonecrosis of the femoral head.OBJECTIVE:To investigate the therapeutic effect and potential mechanism of Cornus Cervi Colla on steroid-induced osteonecrosis of the femoral head in rats by fecal non-targeted fecal metabolomics.METHODS:Thirty SD rats were randomly divided into three groups using a random number table method:the control group(n=10)was injected with normal saline into the right gluteal muscle(injected on the first 3 days of each week for 3 consecutive weeks),and was given pure water gavage(once a day for 6 consecutive weeks).The model group(n=10)was injected with methylprednisolone sodium succinate into the right gluteal muscle(injected on the first 3 days of each week for 3 consecutive weeks)to establish a steroid-induced osteonecrosis of the femoral head model,and was given pure water gavage(once a day for 6 consecutive weeks).The Cornus Cervi Co I la group(n=10)was also established with a steroid-induced osteonecrosis of the femoral head model,and was given Cornus Cervi Col la gavage(once a day for 6 consecutive weeks).After gavage,cecal feces and femoral heads were collected for fecal metabolomics analysis and bone tissue Micro-CT and hematoxylin-eosin staining,respectively.RESULTS AND CONCLUSION:(1)Metabolomics analysis results showed that there were 233 differential metabolites between the Cornus Cervi Col la and model groups,with 65 significantly differing and clearly annotated metabolites.Lipid and amino acid metabolites were significantly increased,with bile acids,sulfated steroids,ephedrine,hypoxanthine,betaine,L-carnitine,B-mouse bile acid,cytidine,4-pyridoxic acid,taurine,N-acetyl-d-glucosamine,and butyric acid being the most impacted(variable weight value VIP＞5).The metabolic pathways of taurine and hypotaurine were crucial in the metabolic regulatory network(pathway impact=0.428 57).(2)Micro-CT scanning results of bone tissue showed that the femoral heads of rats in the model group and the Cornus Cervi Col la group had different degrees of damage;the femoral head contour was irregular;the trabeculae in the subchondral bone of the femoral head were missing and disordered,and some cystic structures were visible.Compared with the model group,the degree of trabecular damage in the rats of the Cornus Cervi Colla group was milder.Hematoxylin-eosin staining results showed that the trabeculae in the subchondral bone of the femoral heads of rats in the model group and the Cornus Cervi Colla group were sparse or interrupted,and the empty bone lacuna rate and adipocyte invasion were increased.Compared with the model group,the empty bone lacuna rate and adipocyte invasion in the subchondral bone of the femoral heads of rats in the Cornus Cervi Colla group were reduced.(3)These results conclude that Cornus Cervi Colla potentially mitigates steroid-induced osteonecrosis of the femoral head through the metabolic processes involving taurine and associated pathways.

BACKGROUND:Osteonecrosis is an orthopedic disease that severely limits joint function,with complex pathogenesis involving multiple risk factors.Cathepsins,as a class of enzymes that play a key role in bone metabolism,are closely related to the proliferation,differentiation of bone cells,and remodeling of the bone matrix.However,previous studies have mostly focused on descriptive analyses,lacking direct evidence of causal relationships.OBJECTIVE:To clarify the potential causal relationship between cathepsins and osteonecrosis and to explore their possible mechanisms by analyzing large-scale sample data from the FinnGen database.METHODS:We obtained osteonecrosis-related data from the FinnGen database,including R9(a total of 359 399 samples:1 385 cases and 358 014 controls)and R10 versions(a total of 392 580 samples:1 543 cases and 391 037 controls).Single nucleotide polymorphisms associated with nine cathepsins(cathepsin B,E,F,G,H,O,S,L2,and Z)were acquired from a previous study(3 301 individuals).Univariate Mendelian randomization,reverse univariate Mendelian randomization,and multivariate Mendelian randomization analyses were conducted using the inverse variance weighted method,MR-Egger method,weighted median method,simple mode method,and weighted mode method.Initially,Mendelian randomization analysis was performed using osteonecrosis data from R9.Additionally,sensitivity analyses were conducted using Cochran's Q test,MR-Egger intercept,MR-PRESSO global test,and leave-one-out analysis to check for horizontal pleiotropy and heterogeneity.Subsequently,a validation analysis study was carried out on the R10 dataset,and a meta-analysis was conducted to combine the two datasets to explore the joint effect.RESULTS AND CONCLUSION:Univariate Mendelian randomization analysis results showed that higher levels of cathepsin B were significantly associated with a reduced risk of osteonecrosis(inverse variance weighted:odds ratio(OR)=0.865,95％confidence interval(CI):0.762-0.982,P=0.025),and no reverse causal relationship was found between the nine cathepsins and osteonecrosis(P＞0.05).These associations were validated by meta-analysis.Multivariate analysis,using the nine cathepsins as covariates,revealed a reverse causal relationship between the levels of cathepsin Band the risk of osteonecrosis(inverse variance weighted:OR=0.8710,95％CI:0.761-0.997,P=0.045),consistent with the results before adjustment.Sensitivity analyses based on heterogeneity and horizontal pleiotropy suggested that the results were relatively robust.This study suggests that there is a causal relationship between high levels of cathepsin B and the reduced risk of osteonecrosis,and it may serve as a biomarker for osteonecrosis,providing new directions and insights for the diagnosis and treatment of osteonecrosis.Although this study is based on data analysis of European populations,these findings have important implications for Chinese biomedical research,especially in understanding disease mechanisms,developing biomarkers,and formulating treatment strategies.They also encourage similar studies conducted on Chinese populations to explore the impact of racial and genetic background differences on the occurrence of osteonecrosis.

Objective In this study,we analyzed the transcriptome sequences of Kupffer cells exposed to simulated microgravity for 3 d and conducted biological experiments to determine how microgravity initiates apoptosis in Kupffer cells. Methods Rotary cell culture system was used to construct a simulated microgravity model.GO and KEGG analyses were conducted using the DAVID database.GSEA was performed using the R language.The STRING database was used to conduct PPI analysis.qPCR was used to measure the IL1B,TNFA,CASP3,CASP9,and BCL2L11 mRNA expressions.Western Blotting was performed to detect the level of proteins CASP3 and CASP 9.Flow cytometry was used to detect apoptosis and mitochondrial membrane cells.Transmission electron microscopy was used to detect changes in the ultrastructure of Kupffer cells. Results Transcriptome Sequencing indicated that simulated microgravity affected apoptosis and the inflammatory state of Kupffer cells.Simulated microgravity improved the CASP3,CASP9,and BCL2L11 expressions in Kupffer cells.Annexin-V/PI and JC-1 assays showed that simulated microgravity promoted apoptosis in Kupffer cells.Simulated microgravity causes M1 polarization in Kupffer cells. Conclusion Our study found that simulated microgravity facilitated the apoptosis of Kupffer cells through the mitochondrial pathway and activated Kupffer cells into M1 polarization,which can secrete TNFA to promote apoptosis.

BACKGROUND:Osteonecrosis is a common refractory disease in clinical practice,and observational studies have suggested that micronutrients may have a prognostic role in osteonecrosis.However,the specific causal association between micronutrients and osteonecrosis is not known. OBJECTIVE:To explore the causal association between micronutrients and osteonecrosis by Mendelian randomization using summary data from a large population-based genome-wide association study(GWAS)for clinical diagnosis and treatment. METHODS:The required exposure and outcome data(calcium,magnesium,iron,vitamin E,carotenoids,retinol&osteonecrosis)were extracted from the IEU OpenGWAS database,GWAS catalog database,and FinnGen database.Data were analyzed by bidirectional Mendelian randomization with inverse-variance weighted as the primary study method,and weighted median method,simple mode method,weighted mode method,and MR-Egger regression to complement the results.The reliability of the data was then verified through sensitivity analyses. RESULTS AND CONCLUSION:(1)The results found a positive correlation between serum iron concentration and osteonecrosis,while no correlation was found for other micronutrients.There was no reverse causality in all the data.(2)The results of sensitivity analysis showed a robust causality.(3)By Mendelian randomization method,this study provided evidence of causality between serum iron concentration and osteonecrosis,and understanding the causality of micronutrient elements on osteonecrosis can help in the clinical diagnosis and treatment of osteonecrosis,which is of great clinical significance.

Objective:To investigate the effect of proprotein convertase subtilisin/kexin type 9 (PCSK9) on platelet activation in sepsis.Methods:① Clinical trial: a prospective study was conducted. Patients with sepsis and septic shock aged ≥ 18 years old who met the diagnostic criteria of Sepsis-3 admitted to the department of intensive care medicine of the Affiliated Hospital of Binzhou Medical College from January to October in 2021 were selected as subjects. Healthy subjects in the same period were taken as healthy control group. Platelet count (PLT) in the first routine blood test after admission was recorded. Venous blood was taken 1 day after diagnosis, and serum PCSK9 level was determined by enzyme-linked immunosorbent assay (ELISA). The differences of PCSK9 level and PLT between the two groups were compared, and subgroup analysis was conducted based on PLT for patients with sepsis. The correlation between PCSK9 level and PLT in septic patients was analyzed by Pearson correlation method. ② Animal experiment: 80 male C57BL/6 mice were randomly divided into control group, sepsis model group [lipopolysaccharide (LPS) group], PCSK9 inhibitor pretreatment group (PCSK9 inhibitor+LPS group) and PCSK9 inhibitor control group (PCSK9 inhibitor group), with 20 mice in each group. The mouse model of sepsis was reproduced by intraperitoneal injection of LPS 12 mg/kg, and the control group and PCSK9 inhibitor group were intraperitoneally injected with the same amount of sterile normal saline. PCSK9 inhibitor+LPS group and PCSK9 inhibitor group were pretreated with PCSK9 inhibitor 5 mg/kg intraperitoneal injection for 7 days before injection of LPS or normal saline, respectively, and the control group and LPS group were injected with an equal amount of sterile normal saline. The lung tissues were taken for pathological and immunohistochemical observation 24 hours after modeling. Blood was taken from the heart for determining PLT. Platelet activation was detected by flow cytometry. The expression level of platelet-activation marker CD40L was detected by Western blotting.Results:① Clinical trial: there were 57 cases in the sepsis group and 27 cases in the healthy control group. Serum PCSK9 level in the sepsis group was significantly higher than that in the healthy control group (μg/L: 232.25±72.21 vs. 191.72±54.92, P < 0.05), and PLT was significantly lower than that in the healthy control group [×10 9/L: 146.00 (75.50, 204.50) vs. 224.00 (194.00, 247.00), P < 0.01]. Subgroup analysis showed that the serum PCSK9 level in the thrombocytopenia patients ( n = 20) was significantly higher than that in the non-thrombocytopenia patients ( n = 37; μg/L: 264.04±60.40 vs. 215.06±72.95, P < 0.01). Correlation analysis showed a significant negative correlation between serum PCSK9 levels and PLT in septic patients ( r = -0.340, P = 0.010). ② Animal experiment: there were no significant pathological changes in lung tissue in the control group and PCSK9 inhibitor group under light microscope, and no significant differences in PLT, platelet activation and plasma CD40L protein expression was found between the two groups. In the LPS group, a large number of inflammatory cells were infiltrated in the pulmonary interstitium, the alveolar structure was damaged obviously, the alveolar septum was widened, the alveolar cavity was extensively bleeding, the capillary dilatation with bleeding and platelet aggregation were found, the PLT was significantly decreased, the platelet activation and the expression level of CD40L protein in plasma were significantly increased. The infiltration of inflammatory cells in lung tissue of mice in the PCSK9 inhibitor+LPS group was reduced to a certain extent, the thickening of alveolar septa was reduced, the platelet aggregation in lung tissue was decreased as compared with the LPS group, the PLT was significantly increased (×10 9/L: 515.83±46.60 vs. 324.83±46.31, P < 0.05), the platelet activation and the expression level of CD40L protein in plasma were significantly decreased [positive expression rate of platelet activation dependent granule surface facial mask protein CD62P: (12.15±1.39)% vs. (18.33±2.74)%, CD40L protein (CD40L/β-actin): 0.77±0.08 vs. 1.18±0.10, both P < 0.05]. Conclusion:PCSK9 level has a certain effect on promoting platelet activation in sepsis, and inhibition of PCSK9 level may have potential research value in improving adverse outcomes caused by sepsis thrombocytopenia.