BACKGROUND: Neoadjuvant therapeutic strategies play a pivotal role in the comprehensive treatment of non-small cell lung cancer (NSCLC). However, lung squamous cell carcinoma (SCC) generally exhibits a more favorable response to neoadjuvant therapy compared with lung adenocarcinoma (ADC). The aim of this study is to elucidate how baseline cancer-associated fibroblasts (CAFs) and tumor-associated endothelial cells (TAECs) influence the differential therapeutic outcomes of neoadjuvant treatment in SCC versus ADC. METHODS: We retrospectively collected pretreatment biopsy samples from 104 patients with stage II-III NSCLC who underwent neoadjuvant chemotherapy (NAC) or neoadjuvant chemoimmunotherapy (NAIC) at Shandong Cancer Hospital between January 1, 2018 and December 31, 2023. Tissue microarrays were constructed using an automated arrayer, and multiplex immunofluorescence staining (α-SMA/CD31/CK/DAPI) was performed to identify CAFs (α-SMA+/CK-) and TAECs (CD31+/CK-). Quantitative analyses included CAFs and TAECs densities, the nearest neighbor distance (NND) between CAFs and TAECs, and their spatial proximity (30 μm). Differences in major pathological response (MPR) between groups, defined as residual viable tumor cells ≤10% in resected specimens after neoadjuvant therapy, were assessed using the χ² test. The Mann-Whitney U test was applied to analyze intergroup differences in quantitative indicators, and receiver operating characteristic (ROC) curve analysis was conducted to evaluate the predictive performance of immune-related markers for MPR in the NAIC cohort. RESULTS: Among the 104 NSCLC patients who received neoadjuvant therapy, 35 underwent NAIC and 69 received NAC. Overall, patients with SCC were more likely to achieve MPR compared with those with ADC (50.0% vs 22.4%, P=0.006). This trend persisted in the NAIC subgroup (72.7% vs 30.8%, P=0.038), whereas no significant difference in MPR rates was observed between SCC and ADC in the NAC subgroup. At baseline, prior to NAIC or NAC, programmed cell death ligand 1 (PD-L1)/programmed cell death 1 (PD-1) expression, CAFs and TAECs densities, CAFs-TAECs NND, and CAFs-TAECs proximity (30 μm) showed no significant differences between SCC and ADC. In patients with SCC receiving NAIC, baseline PD-L1/PD-1 expression, CAFs density, and TAECs density showed not significant differences between MPR and NMPR groups. However, the CAFs-TAECs distance was significantly greater in the MPR group (NND: 31.2 vs 24.7 μm, P=0.038), and the number of TAECs within 30 μm of CAFs was significantly lower (proximity: 1.1 vs 3.6, P=0.038). Univariate Cox regression analysis indicated that low TAECs density was associated with MPR following NAIC (OR=36.00, 95%CI: 2.68-1486.88, P=0.019). Furthermore, ROC analysis demonstrated that baseline CAFs-TAECs NND and proximity (30 μm) exhibited strong predictive performance for MPR in SCC patients treated with NAIC, with an area under the curve (AUC) of 0.893, sensitivity of 0.857, and specificity of 1.000. CONCLUSIONS CAFs are more spatially distant from TAECs and more prone to MPR after NAIC in SCC, which may be related to the reduced interaction of CAFs with TAECs and reduced tumor-associated angiogenesis.
Humans ; Lung Neoplasms/therapy* ; Neoadjuvant Therapy ; Male ; Female ; Middle Aged ; Retrospective Studies ; Endothelial Cells/drug effects* ; Aged ; Cancer-Associated Fibroblasts/drug effects* ; Immunotherapy ; Carcinoma, Squamous Cell/drug therapy* ; Carcinoma, Non-Small-Cell Lung/drug therapy* ; Adult

Objective:The impact of bystander CD8 + T cells (CD8 + Tbys) within the tumor microenvironment on the prognosis of early-stage non-small cell lung cancer (NSCLC) remains unclear, particularly concerning their infiltration differences at the invasive margin (IM) and tumor center (TC). Methods:We retrospectively collected postoperative specimens from 173 patients with primary early-stage NSCLC who underwent radical surgery at the Affiliated Tumor Hospital of Shandong First Medical University from 2014 to 2018. Tissue microarrays encompassing IM and TC regions were prepared and subjected to multicolor immunofluorescence staining (CK/CD8/CD103/DAPI). Image processing and phenotype recognition (CD8 + T cells, CK -CD8 +; CD8 + T bys, CK -CD8 +CD103 -) were performed using inFrom software, and automatic quantitative cell density analysis was conducted using R language. Differences in CD8 + T and CD8 + T bys densities at IM and TC were analyzed using the Mann-Whitney U test. The relationship between CD8 + T, CD8 + T bys and clinicopathological features was examined using the Kruskal-Wallis H test. The impact of CD8 + T and CD8 + T bys on recurrence-free survival (RFS) was evaluated using Kaplan-Meier, log-rank, and Cox proportional hazards models. Results:A total of 173 patients with stage ⅠA-ⅡA NSCLC were included, with a recurrence rate of 26.6% (46/173) and a median RFS of 62.3 months (range: 44.7-71.9 months). CD8 + T and CD8 + T bys densities (1/1 000) were significantly higher in the IM region than in the TC region [70(32, 155) vs. 37(18, 88), P＜0.001; 25(11, 46) vs. 18(7, 34), P=0.002]. No significant association was found between CD8 + T, CD8 + T bys and age, gender, smoking history, histological type, or pathological stage (all P＞0.05). Patients with low-density IM CD8 + T cells had lower RFS compared to those with high-density IM CD8 + T cells ( P=0.021; median RFS not reached), Further analysis revealed that patients with low-density IM CD8 + T bys cell had lower RFS compared to those with high-density IM CD8 + T bys ( P=0.047; median RFS not reached), and low-density IM CD8 + T cell was an independent risk factor for postoperative recurrence ( HR=1.836, 95% CI:1.007-3.347, P=0.048). Joint analysis of IM and TC revealed that patients with low IM CD8 + T bys and high TC CD8 + T bys had significantly lower RFS compared to the other three groups ( P=0.006), and this combination was an independent risk factor for postoperative recurrence in early-stage NSCLC ( HR=2.090, 95% CI:1.162-3.760, P=0.014). Conclusions:The spatial distribution of bystander CD8 + T cells within the primary tumor influences the prognosis of patients with early-stage NSCLC. Patients with low-density IM CD8 + T bys and high-density TC CD8 + T bys are more prone to recurrence after radical surgery.

AIM:This study aims to investigate whether vitamin E succinate(VES)induces autophagy in hu-man gastric cancer cells through the promotion of mitochondria-associated endoplasmic reticulum membranes(MAMs).METHODS:Human gastric cancer cell lines MKN28 and MKN45 were cultured in vitro.Cell viability was assessed us-ing the CCK8 assay,and two cell growth curves were plotted to determine the treatment concentration of VES.Control groups,VES dose groups(MKN28:5,10,20,and 40 mg/L;MKN45:10,20,40,and 80 mg/L),an autophagy-posi-tive control group(rapamycin,RAPA,100 nmol/L),and a MAMs-positive control group(oligomycin A,10 mg/L)were set up.Cells were harvested after 24 h of treatment for subsequent experiments.The formation of autophagosomes and MAMs was observed using transmission electron microscopy.The expression levels of autophagy-related proteins,includ-ing beclin-1,LC3-II/LC3-I,and p62,were detected by Western blot.MAMs labeled with split green fluorescent protein(GFP)were visualized by fluorescence microscopy.The expression of mitofusin 2(MFN2),a key molecule of MAMs,was also detected by Western blot.To inhibit MFN2 specifically,the cells were treated with mitochondrial fusion inhibitor 8(MFI8)and simultaneously transfected with an MFN2 plasmid to achieve MFN2 overexpression(OE-MFN2).The cells were divided into control group,MFI8(20 μmol/L)group,VES groups(20 mg/L for MKN28 cells and 40 mg/L for MKN45 cells),VES+MFI8 group,OE-MFN2+MFI8 group and OE-MFN2+VES+MFI8 group.The MAMs were visualized by fluorescence microscopy,and the expression changes of MFN2,beclin-1 and LC3-II/I were detected by Western blot.RESULTS:The results of the CCK8 assay showed that VES significantly inhibited the viability of both human gastric can-cer cell lines(P<0.05).After VES treatment,the formation of typical autophagosomes and MAMs was observed in both cell lines by transmission electron microscopy.Fluorescence microscopy showed a significant increase in GFP signals of MAMs.Western blot analysis showed that with increasing doses of VES,the expression levels of MFN2,beclin-1,and LC3-II/I were significantly up-regulated,while that of p62 was significantly down-regulated(P<0.05).Compared with VES group,the cells pretreated with MFI8 followed by VES exposure showed markedly reduced GFP signals of MAMs and much lower protein levels of MFN2,beclin-1 and LC3-II/LC3-I(P<0.05).Transfection with an MFN2 overexpression plasmid rescued MFN2 expression.Compared with VES+MFI8 group,the cells in OE-MFN2+VES+MFI8 group had much higher protein expression levels of MFN2,beclin-1 and LC3-II/LC3-I(P<0.05).CONCLUSION:The VES may partici-pates in the regulation of autophagy in human gastric cancer cells by promoting the formation of MAMs.

Objective To investigate the binding interaction between the calmodulin(CaM)mutant D130V and the IQ motif of the car-diac Cav1.2 channel.Methods The binding of mutant CaM-D130V to the IQ motif was predicted by fold recognition modeling,homology modeling,and protein docking.The plasmid was transformed into Escherichia coli BL-21 sensory cells via heat shock at 42 ℃ to induce the expression of glutathione S-transferase(GST)fusion protein.The protein was extracted by ultrasonic fragmentation and purified using GS-4B beads.PreScission protease was applied to remove the GST.SDS-PAGE was performed to detect the purity of protein.A GST pull-down assay was conducted to detect the interaction between CaM-D130V and IQ motif.Results Protein docking results showed that both CaM-WT and CaM-D130V could bind to the IQ motif of the cardiac Cav1.2 channel,but the binding sites of the mutant CaM-D130V to the IQ motif were reduced,and its binding conformation was changed compared with the CaM-WT,with decreased binding energy(|S|reduced from 48.086 6 kcal/mol to 47.309 5 kcal/mol).The GST pull-down assay indicated that the binding of CaM-D130V to IQ motif significantly decreased(P＜0.01),and the affinity was significantly reduced at 2 mmol/L Ca2+concentration compared with CaM-WT.Conclusion The reduced binding ability of CaM-D130V to the IQ motif of the cardiac Cav1.2 channel may contribute to functional alterations in the channel.These findings provide a theoretical basis for understanding the pathogenesis of CaM mutant-associated cardio-vascular diseases as well as targeted therapies.

AIM:This study aims to investigate whether vitamin E succinate(VES)induces autophagy in hu-man gastric cancer cells through the promotion of mitochondria-associated endoplasmic reticulum membranes(MAMs).METHODS:Human gastric cancer cell lines MKN28 and MKN45 were cultured in vitro.Cell viability was assessed us-ing the CCK8 assay,and two cell growth curves were plotted to determine the treatment concentration of VES.Control groups,VES dose groups(MKN28:5,10,20,and 40 mg/L;MKN45:10,20,40,and 80 mg/L),an autophagy-posi-tive control group(rapamycin,RAPA,100 nmol/L),and a MAMs-positive control group(oligomycin A,10 mg/L)were set up.Cells were harvested after 24 h of treatment for subsequent experiments.The formation of autophagosomes and MAMs was observed using transmission electron microscopy.The expression levels of autophagy-related proteins,includ-ing beclin-1,LC3-II/LC3-I,and p62,were detected by Western blot.MAMs labeled with split green fluorescent protein(GFP)were visualized by fluorescence microscopy.The expression of mitofusin 2(MFN2),a key molecule of MAMs,was also detected by Western blot.To inhibit MFN2 specifically,the cells were treated with mitochondrial fusion inhibitor 8(MFI8)and simultaneously transfected with an MFN2 plasmid to achieve MFN2 overexpression(OE-MFN2).The cells were divided into control group,MFI8(20 μmol/L)group,VES groups(20 mg/L for MKN28 cells and 40 mg/L for MKN45 cells),VES+MFI8 group,OE-MFN2+MFI8 group and OE-MFN2+VES+MFI8 group.The MAMs were visualized by fluorescence microscopy,and the expression changes of MFN2,beclin-1 and LC3-II/I were detected by Western blot.RESULTS:The results of the CCK8 assay showed that VES significantly inhibited the viability of both human gastric can-cer cell lines(P<0.05).After VES treatment,the formation of typical autophagosomes and MAMs was observed in both cell lines by transmission electron microscopy.Fluorescence microscopy showed a significant increase in GFP signals of MAMs.Western blot analysis showed that with increasing doses of VES,the expression levels of MFN2,beclin-1,and LC3-II/I were significantly up-regulated,while that of p62 was significantly down-regulated(P<0.05).Compared with VES group,the cells pretreated with MFI8 followed by VES exposure showed markedly reduced GFP signals of MAMs and much lower protein levels of MFN2,beclin-1 and LC3-II/LC3-I(P<0.05).Transfection with an MFN2 overexpression plasmid rescued MFN2 expression.Compared with VES+MFI8 group,the cells in OE-MFN2+VES+MFI8 group had much higher protein expression levels of MFN2,beclin-1 and LC3-II/LC3-I(P<0.05).CONCLUSION:The VES may partici-pates in the regulation of autophagy in human gastric cancer cells by promoting the formation of MAMs.

Objective To investigate the binding interaction between the calmodulin(CaM)mutant D130V and the IQ motif of the car-diac Cav1.2 channel.Methods The binding of mutant CaM-D130V to the IQ motif was predicted by fold recognition modeling,homology modeling,and protein docking.The plasmid was transformed into Escherichia coli BL-21 sensory cells via heat shock at 42 ℃ to induce the expression of glutathione S-transferase(GST)fusion protein.The protein was extracted by ultrasonic fragmentation and purified using GS-4B beads.PreScission protease was applied to remove the GST.SDS-PAGE was performed to detect the purity of protein.A GST pull-down assay was conducted to detect the interaction between CaM-D130V and IQ motif.Results Protein docking results showed that both CaM-WT and CaM-D130V could bind to the IQ motif of the cardiac Cav1.2 channel,but the binding sites of the mutant CaM-D130V to the IQ motif were reduced,and its binding conformation was changed compared with the CaM-WT,with decreased binding energy(|S|reduced from 48.086 6 kcal/mol to 47.309 5 kcal/mol).The GST pull-down assay indicated that the binding of CaM-D130V to IQ motif significantly decreased(P＜0.01),and the affinity was significantly reduced at 2 mmol/L Ca2+concentration compared with CaM-WT.Conclusion The reduced binding ability of CaM-D130V to the IQ motif of the cardiac Cav1.2 channel may contribute to functional alterations in the channel.These findings provide a theoretical basis for understanding the pathogenesis of CaM mutant-associated cardio-vascular diseases as well as targeted therapies.

Objective:The impact of bystander CD8 + T cells (CD8 + Tbys) within the tumor microenvironment on the prognosis of early-stage non-small cell lung cancer (NSCLC) remains unclear, particularly concerning their infiltration differences at the invasive margin (IM) and tumor center (TC). Methods:We retrospectively collected postoperative specimens from 173 patients with primary early-stage NSCLC who underwent radical surgery at the Affiliated Tumor Hospital of Shandong First Medical University from 2014 to 2018. Tissue microarrays encompassing IM and TC regions were prepared and subjected to multicolor immunofluorescence staining (CK/CD8/CD103/DAPI). Image processing and phenotype recognition (CD8 + T cells, CK -CD8 +; CD8 + T bys, CK -CD8 +CD103 -) were performed using inFrom software, and automatic quantitative cell density analysis was conducted using R language. Differences in CD8 + T and CD8 + T bys densities at IM and TC were analyzed using the Mann-Whitney U test. The relationship between CD8 + T, CD8 + T bys and clinicopathological features was examined using the Kruskal-Wallis H test. The impact of CD8 + T and CD8 + T bys on recurrence-free survival (RFS) was evaluated using Kaplan-Meier, log-rank, and Cox proportional hazards models. Results:A total of 173 patients with stage ⅠA-ⅡA NSCLC were included, with a recurrence rate of 26.6% (46/173) and a median RFS of 62.3 months (range: 44.7-71.9 months). CD8 + T and CD8 + T bys densities (1/1 000) were significantly higher in the IM region than in the TC region [70(32, 155) vs. 37(18, 88), P＜0.001; 25(11, 46) vs. 18(7, 34), P=0.002]. No significant association was found between CD8 + T, CD8 + T bys and age, gender, smoking history, histological type, or pathological stage (all P＞0.05). Patients with low-density IM CD8 + T cells had lower RFS compared to those with high-density IM CD8 + T cells ( P=0.021; median RFS not reached), Further analysis revealed that patients with low-density IM CD8 + T bys cell had lower RFS compared to those with high-density IM CD8 + T bys ( P=0.047; median RFS not reached), and low-density IM CD8 + T cell was an independent risk factor for postoperative recurrence ( HR=1.836, 95% CI:1.007-3.347, P=0.048). Joint analysis of IM and TC revealed that patients with low IM CD8 + T bys and high TC CD8 + T bys had significantly lower RFS compared to the other three groups ( P=0.006), and this combination was an independent risk factor for postoperative recurrence in early-stage NSCLC ( HR=2.090, 95% CI:1.162-3.760, P=0.014). Conclusions:The spatial distribution of bystander CD8 + T cells within the primary tumor influences the prognosis of patients with early-stage NSCLC. Patients with low-density IM CD8 + T bys and high-density TC CD8 + T bys are more prone to recurrence after radical surgery.

Objective To explore the clinical efficacy of low molecular weight heparin combined with insulin in the treatment of hyper-triglyceridemic-acute pancreatitis(HTG-AP).Methods A total of 106 patients diagnosed with HTG-AP who were admitted to the department of gastroenterology of Huaibei People's Hospital from May 2022 to July 2023 were selected as the research objects.According to the random number table method,the low-molecular heparin group(35 cases,received a 5 000 U subcutaneous injection low-molecular heparin once every 12 hours for 6 days),the insulin group(35 cases,received intravenous insulin pumping at a rate of 2 U/h,with careful monitoring of the patient's random blood glucose levels to prevent hypoglycemia),and the combination therapy group(36 cases,received both low-molecular heparin and insulin).Before treatment and at 1,2,and 6 days after treatment,the difference of serum triacylglycerol(TG),total cholesterol(TC),blood amylase,inflammatory factors[C-reactive protein(CRP),interleukin-6(IL-6)],calcium ions,and creatinine levels among the three groups were compared.The modified computed tomography severity index(MCTSI)scores,acute physiology and chronic health evaluationⅡ(APACHEⅡ),hospital length of stay,and hospital costs before and after 6 days of treatment were observed.Results After treatment,the TC of all three groups significantly decreased compared to before treatment(P<0.05),but there was no significant difference among the three groups.The calcium ion levels of the three groups did not show a statistically significant difference before and after treatment.After 6 days of treatment,the creatinine levels of the three groups significantly decreased compared to before treatment,but there was no significant difference among the three groups.After 2 days of treatment,serum TG levels were significantly lower in the combination therapy group and insulin group compared to the low-molecular heparin group(mmol/L:4.6±1.7,4.4±1.8 vs.5.6±2.0,both P<0.05).However,there was no statistically significant difference between the combination therapy group and the insulin group.After 6 days of treatment,the combination therapy group showed significantly lower levels of serum TG,blood amylase,CRP,and IL-6 compared to the insulin group and the low-molecular heparin group[TG(mmol/L):2.8±1.9 vs.4.3±1.9,5.0±2.2,blood amylase(U/L):36.0(32.0,45.0)vs.59.0(43.0,71.0),52.0(45.0,64.0),CRP(mg/L):12.9(8.8,29.7)vs.35.3(21.7,50.3),31.4(23.0,45.1),IL-6(ng/L):15.4(9.8,23.5)vs.25.6(16.4,51.5),32.9(14.7,41.4),all P<0.05].After 6 days of treatment,the APACHEⅡscores of all three groups decreased significantly(all P<0.05).The MCTSI scores of the insulin group and the combined treatment group also decreased significantly compared to before treatment.Furthermore,the MCTSI and APACHEⅡscores of the combination therapy group were significantly lower than those of the low-molecular heparin group and the insulin group(MCTSI score:2.3±0.7 vs.3.3±1.7,2.9±1.3,APACHEⅡscore:1.3±1.2 vs.2.5±2.4,2.6±2.5,all P<0.05).The combination therapy group had significantly lower length of hospital stay and treatment cost compared to the low molecular heparin and insulin groups[length of hospital stay(days):6.9±1.6 vs.8.8±3.4,8.5±2.8,and cost of treatment(yuan):6 040.5(5 239.4,7 105.9)vs.6 696.4(5 791.5,11 026.2),6 918.5(6 087.9,10 080.8),all P<0.05].Conclusions The combination of low-molecular heparin and insulin treatment can significantly reduce serum TG and inflammatory factor levels,as well as the severity and duration of the disease.This approach can also reduce the cost of treatment.Therefore,it is worth promoting and applying in clinical settings.

Objective:To investigate the prevalence of diabetes in the elderly aged ≥60 years in Liaoning Province from 2017 to 2019 and analyze the impact of blood glucose control on all-cause mortality and cardiovascular disease (CVD) mortality.Methods:A survey was conducted in the elderly aged ≥60 years in Liaoning from 2017 to 2019 to collect the information about the prevalence of diabetes and other chronic diseases in the diabetes patients. The mortality of the enrolled subjects was investigated in September 2023. Cox proportional hazards regression models were used to estimate the association between blood glucose control in the elderly with diabetes and the risks of all-cause mortality and CVD mortality.Results:The crude prevalence of diabetes in the elderly aged ≥60 years was 20.2% (2 014/9 958) in Liaoning from 2017 to 2019, and the standardized prevalence rate was 19.9%. The prevalence rates of hypertension, dyslipidemia, and overweight/obesity in the diabetes patients were 77.0%, 51.7%, and 67.5% respectively. The median follow-up time was 5.5 years, and the all-cause mortality and CVD mortality rates in the diabetes patients were 244.3/10 000 person-years and 142.9/10 000 person-years, respectively. The results of the Cox proportional hazards regression model analysis showed that compared with non-diabetic individuals, diabetes patients had an increased risk of all-cause mortality by 1.68 times [hazard ratio ( HR)=1.68, 95% CI: 1.44-1.94] and an increased risk of CVD mortality by 1.56 times ( HR=1.56, 95% CI: 1.29-1.89). The differences in risks of all-cause mortality and CVD mortality between the diabetes patients with normal fasting blood glucose and glycated hemoglobin levels and people without diabetes were not significant (all P>0.05). The failure to meet either the FPG or HbA1c target increased the risk of all-cause mortality (all P<0.05). For individuals who failed to meet the HbA1c target, there was an increased risk of CVD mortality (all P<0.05). Conclusions:The comorbidity rate of chronic diseases was higher in the elderly with diabetes than in the elderly without diabetes in Liaoning. Elderly diabetes patients can benefit from good blood glucose control.

Objective To construct an in vitro"metabolic memory"cell model of HT-22 mouse hippocampal neurons induced by high glucose,and to investigate the effect of"metabolic memory"on apoptosis and histone acetylation in HT-22 cells.Methods HT-22 cells were cultured in high glucose medium(glucose concentration was 55 mmol/L)and conventional glucose medium(glucose concentration was 25 mmol/L),and cells were divided into the control group(NG 4,6 and 8 groups,25 mmol/L glucose was cultured for 4,6 and 8 days,respectively),the high glucose group(HG 4,6 and 8 groups,respectively)and the metabolic memory group(HG2NG2,HG2NG4,HG2NG6,HG4NG2 and HG4NG4 groups,high glucose culture for 2 days to 25 mmol/L glucose culture for 2,4 or 6 days,high glucose culture for 4 days to 25 mmol/L glucose culture for 2 or 4 days).Cell viability was detected by CCK-8 method.The release of lactate dehydrogenase(LDH)in cell culture supernatant was detected,and the optimal time to establish a"metabolic memory"model was selected.Subsequently,cells were divided into the NG4 group,the NG8 group,the HG4 group,the HG4NG4 group and the HG8 group,and the cell morphology of each group was observed by optical microscope.The apoptosis rate was detected by flow cytometry.The activities of deacetylase(HDAC)and histone acetyltransferase(HAT)were detected by enzyme-linked immunosorbent assay(ELISA).Western blot assay was used to detect expression levels of histone deacetylase 4(HDAC4),B lymphocyte tumor 2(Bcl-2),Bcl-2 related X protein(Bax)and Caspase-3 protein.Results The HG4NG4 group was the ideal cell model with high glucose metabolic memory.Cells of the NG4 group and the NG8 group were interwoven into a dense network,growing well,with spindle shaped cells and distinct synaptic structures.However,in the HG4 group and the HG8 group,the cell body became round,synaptic structure disappeared and growth was inhibited.In the HG4NG4 group,the number of cells increased but their morphology was damaged.Results of flow cytometry showed that compared with the NG8 group,the apoptosis rates were significantly increased in the HG8 group and the HG4NG4 group(P＜0.05).ELISA results showed that compared with the NG8 group,the expression levels of HDAC4,Bax,and Caspase-3 proteins increased in the HG8 group and the HG4NG4 group,while the expression level of Bcl-2 protein significantly decreased(P＜0.05).Compared with the HG8 group,there were no significant differences in protein expression levels of HAT and HDAC in the HG4NG4 group.Western blot reslts showed that compared with the NG8 group,the levels of HDAC4,Bax and Caspase-3 protein increased in the HG8 group and the HG4NG4 group(P＜0.05).Compared with the HG8 group,there were no significant differences in protein expression levels in the HG4NG4 group.Conclusion HT-22 mouse hippocampal neurons cultured with 55mmol/L high glucose for 4 days,and then cultured with 25 mmol/L glucose for 4 days are the ideal"metabolic memory"cell model.The mechanism may be related to the increased activity of HDAC,HAT and HDAC4 expression in the hyperglycemic model.