Alleviation of acute pancreatitis-associated lung injury by inhibiting the p38 mitogen-activated protein kinase pathway in pulmonary microvascular endothelial cells

BACKGROUND Previous reports have suggested that the p38 mitogen-activated protein kinase signaling pathway is involved in the development of severe acute pancreatitis(SAP)-related acute lung injury(ALI).Inhibition of p38 by SB203580 blocked the inflammatory responses in SAP-ALI.However,the precise mechanism associated with p38 is unclear,particularly in pulmonary microvascular endothelial cell(PMVEC)injury.AIM To determine its role in the tumor necrosis factor-alpha(TNF-α)-induced inflammation and apoptosis of PMVECs in vitro.We then conducted in vivo experiments to confirm the effect of SB203580-mediated p38 inhibition on SAP-ALI.METHODS In vitro,PMVEC were transfected with mitogen-activated protein kinase kinase 6(Glu),which constitutively activates p38,and then stimulated with TNF-α.Flow cytometry and western blotting were performed to detect the cell apoptosis and inflammatory cytokine levels,respectively.In vivo,SAP-ALI was induced by 5%sodium taurocholate and three different doses of SB203580(2.5,5.0 or 10.0 mg/kg)were intraperitoneally injected prior to SAP induction.SAP-ALI was assessed by performing pulmonary histopathology assays,measuring myeloperoxidase activity,conducting arterial blood gas analyses and measuring TNF-α,interleukin(IL)-1βand IL-6 levels.Lung microvascular permeability was measured by determining bronchoalveolar lavage fluid protein concentration,Evans blue pulmonary cells was confirmed by performing a terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling analysis and examining the Bcl2,Bax,Bim and cle-caspase3 levels.The proteins levels of P-p38,NFκB,IκB,P-signal transducer and activator of transcription-3,nuclear factor erythroid 2-related factor 2,HO-1 and Myd88 were detected in the lungs to further evaluate the potential mechanism underlying the protective effect of SB203580.RESULTS In vitro,mitogen-activated protein kinase(Glu)transfection resulted in higher apoptotic rates and cytokine(IL-1βand IL-6)levels in TNF-α-treated PMVECs.In vivo,SB2035080 attenuated lung histopathological injury,decreased inflammatory activity(TNF-α,IL-1β,IL-6 and myeloperoxidase)and preserved pulmonary function.Furthermore,SB203580 significantly reversed changes in the bronchoalveolar lavage fluid protein concentration,Evans blue accumulation,terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive cell numbers,apoptosis-related proteins(cle-caspase3,Bim and Bax)and endothelial microstructure.Moreover,SB203580 significantly reduced the pulmonary P-p38,NFκB,P-signal transducer and activator of transcription-3 and Myd88 levels but increased the IκB and HO-1 levels.CONCLUSION p38 inhibition may protect against SAP-ALI by alleviating inflammation and the apoptotic death of PMVECs.

Baicalin Induces IFN-α/β and IFN-γ Expressions in Cultured Mouse Pulmonary Microvascular Endothelial Cells

We studied the effect of baicalin,an extract from Radix Scutellariae（a traditional Chinese medicine） in inducing mouse pulmonary microvascular endothelial cells（MPMVECs） to produce interferons（IFNs）.MPMVECs were cultured in vitro in the presence of different concentrations of baicalin（10,20,and 30 μg mL-1）,and the cells and the culture media were harvested at various time intervals.The proteins and mRNA levels（relative to β-actin） of IFN-α/β and IFN-γ were analyzed by RT-PCR and enzyme-linked immunosorbent assay（ELISA）.It was observed that baicalin substantially up-regulated the expression of IFN-α/β and IFN-γ.In all baicalin-treated groups,the relative levels of IFN-α/β and IFN-γ mRNAs peaked after 12 h of culturing,and IFN-α/β and IFN-γ proteins peaked after 24 h of culturing.These results suggest that baicalin can effectively induce the expression of IFNs in pulmonary microvascular endothelial cells,and thus potentially act as an antiviral compound.This study may provide background information for developing new antiviral drugs based on baicalin.

Inhibitory effects of safranal on laser-induced choroidal neovascularization and human choroidal microvascular endothelial cells and related pathways analyzed with transcriptome sequencing

AIM:To determine the effects of safranal on choroidal neovascularization(CNV)and oxidative stress damage of human choroidal microvascular endothelial cells(HCVECs)and its possible mechanisms.METHODS:Forty-five rats were used as a laser-induced CNV model for testing the efficacy and safety of safranal(0.5 mg/kg·d,intraperitoneally)on CNV.CNV leakage on fluorescein angiography(FA)and CNV thickness on histology was compared.HCVECs were used for a H_(2)O_(2)-induced oxidative stress model to test the effect of safranal in vitro.MTT essay was carried to test the inhibition rate of safranal on cell viability at different concentrations.Tube formation was used to test protective effect of safranal on angiogenesis at different concentrations.mRNA transcriptome sequencing was performed to find the possible signal pathway.The expressions of different molecules and their phosphorylation level were validated by Western blotting.RESULTS:On FA,the average CNV leakage area was 0.73±0.49 and 0.31±0.11 mm^(2)(P=0.012)in the control and safranal-treated group respectively.The average CNV thickness was 127.4±18.75 and 100.6±17.34μm(P=0.001)in control and safranal-treated group.Under the condition of oxidative stress,cell proliferation was inhibited by safranal and inhibition rates were 7.4%-35.4%at the different concentrations.For tube formation study,the number of new branches was 364 in control group and 35,42,and 17 in 20,40,and 80μg/mL safranal groups respectively(P<0.01).From the KEGG pathway bubble graph,the PI3K-AKT signaling pathway showed a high gene ratio.The protein expression was elevated of insulin receptor substrate(IRS)and the phosphorylation level of PI3K,phosphoinositide-dependent protein kinase 1/2(PDK1/2),AKT and Bcl-2 associated death promoter(BAD)was also elevated under oxidative stress condition but inhibited by safranal.CONCLUSION:Safranal can inhibit CNV both in vivo and in vitro,and the IRS-PI3K-PDK1/2-AKT-BAD signaling pathway is involved in the pathogenesis of CNV.

The role of heme-oxygenase-1 in pathogenesis of cerebral malaria in the co-culture model of human brain microvascular endothelial cell and ITG Plasmodium falciparum-infected red blood cells

Objective: To investigate the role of human host heme-oxygenase-1(HO-1) in pathogenesis of cerebral malaria in the in vitro model,Methods: The effect of human host HO-1 [human brain microvascular endothelial cell(HBMEC)] on hemoglobin degradation in the co-culture model of HBMEC and ITG Plasmodium falciparum-infected red cells(i RBC) through measurement of the enzymatic products iron and bilirubin,Results: Following exposure to the HO-1 inducer Co PPIX at all concentrations,the HBMEC cells apoptosis occurred,which could be prominently observed at 15 μM of 3 h exposure,In contrast,there was no significant change in the morphology in the non-exposed i RBC at all concentrations and exposure time,This observation was in agreement with the levels of the enzymatic degradation products iron and bilirubin,of which the highest levels(106.03 and 1 753.54% of baseline level,respectively) were observed at 15 μM vs,20 μM at 3 h vs,24 h exposure,For the effect of the HO-1 inhibitor Zn PPIX,HBMEC cell morphology was mostly unchanged,but significant inhibitory effect on cell apoptosis was seen at 10 μM for the exposure period of 3 h(37.17% of baseline level),The degree of the inhibitory effect as reflected by the level of iron produced was not clearly observed(highest effect at 10 μM and 3 h exposure),Conclusions: Results provide at least in part,insight into the contribution of HO-1 on CM pathogenesis and need to be confirmed in animal model.

Down-regulation of histone deacetylase 7 reduces biological activities of retinal microvascular endothelial cells under high glucose condition and related mechanism

AIM:To investigate the expression and effect of histone deacetylase 7(HDAC7)in human retinal microvascular endothelial cells(HRMECs)under high glucose condition and related mechanism,and the expression of HDAC7 in the retinal tissue in diabetic rats.METHODS:The expression of HDAC7 in HRMECs under high glucose and the retinal tissue from normal or diabetic rats were detected with immunohistochemistry and Western blot.LV-shHDAC7 HRMECs were used to study the effect of HDAC7 on cell activities.Cell count kit-8(CCK-8),5-ethynyl2’-deoxyuridine(EdU),flow cytometry,scratch test,Transwell test and tube formation assay were used to examine the ability of cell proliferation,migration,and angiogenesis.Finally,a preliminary exploration of its mechanism was performed by Western blot.RESULTS:The expression of HDAC7 was both upregulated in retinal tissues of diabetic rats and high glucosetreated HRMECs.Down-regulation of HDAC7 expression significantly reduced the ability of proliferation,migration,and tube formation,and reversed the high glucose-induced high expression of CDK1/Cyclin B1 and vascular endothelial growth factor in high glucose-treated HRMECs.CONCLUSION:High glucose can up-regulate the expression of HDAC7 in HRMECs.Down-regulation of HDAC7 can inhibit HRMECs activities.HDAC7 is proposed to be involved in pathogenesis of diabetic retinopathy and a therapeutic target.

β-Estradiol 17-acetate enhances the in vitro vitality of endothelial cells isolated from the brain of patients subjected to neurosurgery

In the current landscape of endothelial cell isolation for building in vitro models of the blood-brain barrier,our work moves towards reproducing the features of the neurovascular unit to achieve glial compliance through an innovative biomimetic coating technology for brain chronic implants.We hypothesized that the autologous origin of human brain mic rovascular endothelial cells(hBMECs)is the first requirement for the suitable coating to prevent the glial inflammato ry response trigge red by foreign neuroprosthetics.Therefo re,this study established a new procedure to preserve the in vitro viability of hBMECs isolated from gray and white matter specimens taken from neurosurge ry patients.Culturing adult hBMECs is generally considered a challenging task due to the difficult survival ex vivo and progressive reduction in proliferation of these cells.The addition of 10 nMβ-estradiol 17-acetate to the hBMEC culture medium was found to be an essential and discriminating factor promoting adhesion and proliferation both after isolation and thawing,suppo rting the well-known protective role played by estrogens on microvessels.In particular,β-estradiol 17-acetate was critical for both freshly isolated and thawed female-derived hBMECs,while it was not necessary for freshly isolated male-derived hBMECs;however,it did countera ct the decay in the viability of the latter after thawing.The tumo r-free hBMECs were thus cultured for up to 2 months and their growth efficiency was assessed befo re and after two periods of cryopreservation.Des pite the thermal stress,the hBMECs remained viable and suitable for re-freezing and storage for several months.This approach increasing in vitro viability of hBMECs opens new perspectives for the use of cryopreserved autologous hBMECs as biomimetic therapeutic tools,offering the potential to avoid additional surgical sampling for each patient.

Quercetin protects human brain microvascular endothelial cells from fibrillarβ-amyloid_(1–40)-induced toxicity

Amyloid beta-peptides(Aβ) are known to undergo active transport across the blood-brain barrier, and cerebral amyloid angiopathy has been shown to be a prominent feature in the majority of Alzheimer's disease. Quercetin is a natural flavonoid molecule and has been demonstrated to have potent neuroprotective effects, but its protective effect on endothelial cells under Aβ-damaged condition is unclear. In the present study, the protective effects of quercetin on brain microvascular endothelial cells injured by fibrillar Aβ_(1–40)(f Aβ_(1–40)) were observed. The results show that f Aβ_(1–40)-induced cytotoxicity in human brain microvascular endothelial cells(h BMECs) can be relieved by quercetin treatment. Quercetin increases cell viability, reduces the release of lactate dehydrogenase, and relieves nuclear condensation.Quercetin also alleviates intracellular reactive oxygen species generation and increases superoxide dismutase activity. Moreover, it strengthens the barrier integrity through the preservation of the transendothelial electrical resistance value, the relief of aggravated permeability, and the increase of characteristic enzyme levels after being exposed to f Aβ_(1–40). In conclusion, quercetin protects h BMECs from f Aβ_(1–40)-induced toxicity.

D-galactose induces replicative senescence of rat pulmonary microvascular endothelial cells

To explore the relationship between senescent pulmonary microvascular endothelial cells (PMVECs) in-duced by D-galactose (D-gal) and apoptosis, PMVECs were cultured with DMEM containing D-gal (10 g/L) and identi-fied by the following methods. We found that about 90% senescent cells were b-galactosidase positive cells, and 90% cells entered an irreversible G1 growth arrest. The cells in S and G2/M phases nearly disappeared. These results indi-cated that PMVECs ageing model induced by D-gal was es-tablished successfully. Compared with the control, PMVECs induced by D-gal showed that chromatin condensation and apoptotic bodies in nucleus were detected by fluorescence microscopy and transmission electron microscopy. Apoptotic cells in the early and middle phases increased significantly (39.8 2.8)% vs. (14.0 3.7)%. Typical Sub-G1 peak in the late apoptosis phase appeared in the terminal stage of PMVECs ageing. It is concluded that D-gal induces cultured PMVECs replicative senescence. Senescent PMVECs in-duced by D-gal were sensitive to apoptosis. Apoptosis is the regular feature of senescent PMVECs.

Single-cell RNA-seq and bulk-seq identify RAB17 as a potential regulator of angiogenesis by human dermal microvascular endothelial cells in diabetic foot ulcers

Background:Angiogenesis is crucial in diabetic wound healing and is often impaired in diabetic foot ulcers(DFUs).Human dermal microvascular endothelial cells(HDMECs)are vital components in dermal angiogenesis;however,their functional and transcriptomic characteristics in DFU patients are not well understood.This study aimed to comprehensively analyse HDMECs from DFU patients and healthy controls and find the potential regulator of angiogenesis in DFUs.Methods:HDMECs were isolated from skin specimens of DFU patients and healthy controls via magnetic-activated cell sorting.The proliferation,migration and tube-formation abilities of the cells were then compared between the experimental groups.Both bulk RNA sequencing(bulk-seq)and single-cell RNA-seq(scRNA-seq)were used to identify RAB17 as a potential marker of angiogenesis,which was further confirmed via weighted gene co-expression network analysis(WGCNA)and least absolute shrink and selection operator(LASSO)regression.The role of RAB17 in angiogenesis was examined through in vitro and in vivo experiments.Results:The isolated HDMECs displayed typical markers of endothelial cells.HDMECs isolated from DFU patients showed considerably impaired tube formation,rather than proliferation or migration,compared to those from healthy controls.Gene set enrichment analysis(GSEA),fGSEA,and gene set variation analysis(GSVA)of bulk-seq and scRNA-seq indicated that angiogenesis was downregulated in DFU-HDMECs.LASSO regression identified two genes,RAB17 and CD200,as characteristic of DFU-HDMECs;additionally,the expression of RAB17 was found to be significantly reduced in DFU-HDMECs compared to that in the HDMECs of healthy controls.Overexpression of RAB17 was found to enhance angiogenesis,the expression of hypoxia inducible factor-1α and vascular endothelial growth factor A,and diabetic wound healing,partially through the mitogen-activated protein kinase/extracellular signal-regulated kinase signalling pathway.Conclusions:Our findings suggest that the impaired angiogenic capacity in DFUs may be related to the dysregulated expression of RAB17 in HDMECs.The identification of RAB17 as a potential molecular target provides a potential avenue for the treatment of impaired angiogenesis in DFUs.

胃饥饿素对高糖下视网膜微血管内皮细胞氧化应激及铁死亡的抑制作用

目的研究胃饥饿素对高糖下人视网膜微血管内皮细胞(HRMEC)氧化应激及铁死亡的影响。方法将体外培养的HRMEC分为对照组、高糖组、高糖+胃饥饿素组,分别采用常规培养基、含30 mmol/L D-葡萄糖培养基、含30 mmol/L D-葡萄糖+10 nmol/L胃饥饿素培养基培养24 h。采用细胞计数试剂盒8检测细胞增生情况;采用流式细胞术检测细胞活性氧簇(ROS)水平;采用试剂盒检测细胞中氧化应激指标还原型谷胱甘肽(GSH)浓度、丙二醛(MDA)浓度、超氧化物歧化酶(SOD)活性及Fe^(2+)浓度;采用透射电子显微镜观察线粒体结构;采用Western blot法检测HRMEC中铁死亡关键分子谷胱甘肽过氧化合物酶4(GPX4)、溶质载体家族7成员11(SLC7A11)蛋白表达。结果对照组、高糖组、高糖+胃饥饿素组细胞增生率分别为(100.62±3.40)%、(63.74±4.25)%和(88.19±4.65)%,ROS荧光强度分别为15512.20±1347.53、46457.00±1072.65和22220.87±1669.20,GSH浓度分别为(68.52±7.61)、(21.45±1.57)和(55.68±5.15)μmol/L,MDA浓度分别为(0.79±0.10)、(2.47±0.27)和(1.08±0.15)μmol/L,SOD活性分别为(111.67±10.32)、(37.75±5.92)和(97.45±9.12)U/ml,Fe^(2+)浓度分别为(3.02±0.30)、(9.45±0.71)和(4.63±0.32)mmol/mgprot。各组间细胞增生率、ROS荧光强度、GSH浓度、MDA浓度、SOD活性及Fe^(2+)浓度总体比较,差异均有统计学意义(F=61.82、414.59、61.28、67.24、61.64,146.14,均P<0.001);与对照组相比,高糖组细胞增生率、GSH浓度和SOD活性均明显降低,ROS荧光强度、MDA浓度和Fe^(2+)浓度明显升高,差异均有统计学意义(均P<0.05);与高糖组相比,高糖+胃饥饿素组细胞增生率、GSH浓度和SOD活性明显升高,ROS荧光强度、MDA浓度和Fe^(2+)浓度明显降低,差异均有统计学意义(均P<0.05)。与对照组相比,高糖组细胞内线粒体铁死亡现象明显;与高糖组相比,高糖+胃饥饿素组线粒体状态明显改善。各组间细胞中GPX4、SLC7A11蛋白相对表达量总体比较,差异均有统计学意义(F=63.94、182.84,均P<0.001);与对照组相比,高糖组和高糖+胃饥饿素组细胞中GPX4、SLC7A11蛋白相对表达量均明显降低,差异均有统计学意义(均P<0.05);与高糖组相比,高糖+胃饥饿素组2种蛋白表达水平均升高,差异均有统计学意义(均P<0.01)。结论胃饥饿素可促进高糖下的HRMEC增生,抑制高糖诱导的氧化应激和铁死亡。

秃疮花异紫堇碱对LPS诱导的牛肺微血管内皮细胞炎症因子和TLR2/MYD88/NF-κB通路的影响

试验旨在探究秃疮花异紫堇碱(ICD)对脂多糖(LPS)诱导的牛肺微血管内皮细胞(CPA 47)炎症因子和Toll样受体2/髓样分化因子88/核转录因子-κB(TLR2/MYD88/NF-κB)通路的影响。选取CPA 47分为5组接种于6孔板中,每组设置4孔,对照组细胞加入1640培养基,LPS组加入脂多糖处理建立炎症模型,ICD高剂量组细胞加入20 mg/L ICD+50μg/L LPS,ICD中剂量组细胞加入15 mg/L ICD+50μg/L LPS,ICD低剂量组细胞加入10 mg/L ICD+50μg/L LPS。分别利用ELISA检测各组的炎性因子含量,实时荧光定量PCR检测TLR2/MYD88/NF-κB通路中关键基因的表达量,免疫印迹法(Western blot)检测上述通路中各蛋白含量。结果显示,与对照组相比,LPS处理组和ICD低剂量组牛肺微血管内皮细胞白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、白细胞介素-8(IL-8)和肿瘤坏死因子(TNF-α)含量显著升高(P<0.05),TLR2、NF-κB、MYD88的mRNA表达量和蛋白含量显著升高(P<0.05)。与LPS组相比,ICD高、中剂量组中IL-1β、IL-6、IL-8和TNF-α含量显著降低(P<0.05),TLR2、NF-κB、MYD88的mRNA表达量和蛋白含量显著降低(P<0.05)。研究表明,15~20 mg/L ICD可以有效缓解LPS诱导的牛肺微血管内皮细胞的炎症反应,抑制LPS诱导的牛肺微血管内皮细胞TLR2/MYD88/NF-κB炎症通路的激活。

卡巴胆碱对失血性休克大鼠肺微血管内皮细胞功能的影响

目的 观察大鼠失血性休克时卡巴胆碱对肺微血管内皮细胞的作用。方法 将30只健康雄性SD大鼠(SPF级)按每组10只随机分为假休克组(SS组)、失血性休克组(HS组)、失血性休克+卡巴胆碱组(CBL组)。失血性休克动物模型按照Wiggers改良法制作,各组模型制备完毕后6 h,经右侧股动脉采血,检测肿瘤坏死因子-α(TNF-α)水平,取右肺下叶肺组织检测Src抑制的蛋白激酶C的底物(SSeCKS)、E-选择素蛋白质水平,取右肺下叶行透射电镜检查肺微血管内皮细胞超微结构。结果 SS组表达少量的TNF-α、SSeCKS、E-选择素,HS组和CBL组表达升高(P<0.05),与HS组相比,CBL组表达降低(P<0.05)。SS组肺微血管内皮细胞细胞膜表面光滑,细胞膜、细胞质、细胞核形态结构正常;HS组肺微血管内皮细胞出现细胞水肿、坏死和凋亡表现(细胞膜表面皱折、细胞膜表面凹凸不平、细胞器水肿、异染色质染色加深边集等);CBL组较SS组,细胞有所损伤,但好于HS组。结论 大鼠失血性休克时卡巴胆碱对肺微血管内皮细胞具有保护作用,也可通过抑制炎症细胞合成和释放炎症介质减轻对血管内皮细胞的损伤。

温石棉对内皮细胞Wnt5a、p16和p21表达的影响

目的探讨温石棉对人脐静脉内皮细胞(HUVECs)的影响。方法实验组以50、100、200 mg/L温石棉纤维液刺激HUVECs 24、48、72 h,对照组仅加RPMI 1640培养基培养细胞,观察细胞形态变化,β-半乳糖苷酶法分析细胞衰老情况,四甲基偶氮唑蓝法检测细胞存活率。采用实时荧光定量PCR法检测细胞中Wnt5a、p16和p21 mRNA的表达情况。结果实验组HUVECs多呈梭形,部分呈圆形或不规则形,出现裸核及空泡现象,可见死亡细胞。随温石棉质量浓度及暴露时间的增加,细胞活性逐渐降低,衰老细胞逐渐增多。100 mg/L温石棉处理HUVECs 24 h时,细胞生长较活跃。与对照组相比,实验组Wnt5a、p16和p21 mRNA表达水平均增高(P<0.05)。结论温石棉可促进HUVECs衰老,Wnt5a、p16和p21参与此过程。

丹参酮ⅡA对脓毒症肺微血管内皮细胞损伤的保护作用

目的探寻丹参酮ⅡA对脓毒症肺血管内皮细胞损伤的保护作用。方法采用盲肠结扎穿孔术构建脓毒症肺损伤小鼠模型,分为6组:假手术组、模型组、丹参酮1组(10 mg/kg)、丹参酮2组(30 mg/kg)、丹参酮3组(50 mg/kg)、丹参酮4组(100 mg/kg)。药物干预24 h后检测肺组织病理变化、肺微血管通透性、肺组织湿/干重比、白细胞计数以及炎症因子等各项指标,假手术组仅行盲肠探查术。结果丹参酮各组较模型组小鼠肺组织损伤及评分均减轻(P<0.05)。与模型组比较,丹参酮各组小鼠肺组织Evans Blue含量、肺组织湿/干比明显降低(P<0.05),BALF白细胞计数、蛋白含量、炎症因子明显减少(均P<0.05),且呈剂量依赖性,其中丹参酮2组、丹参酮3组和丹参酮4组之间,肺组织病理损伤、Evans Blue含量、肺组织湿/干比以及肺泡灌洗液中白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)表达水平差异无统计学意义(均P>0.05)。结论丹参酮ⅡA能够剂量依赖性地降低脓毒症所致的肺微血管内皮细胞损伤,从而改善肺损伤;30 mg/kg剂量的丹参酮ⅡA即可达到最佳效果。

中性粒细胞胞外诱捕网通过激活NLRP3炎症小体诱导人肺微血管内皮细胞焦亡

目的探讨中性粒细胞胞外诱捕网作用于肺微血管内皮细胞并诱发内皮细胞死亡的具体机制。方法以200 ng/mL的体外分离的中性粒细胞胞外诱捕网刺激人肺微血管内皮细胞,碘化丙锭染色法检测细胞死亡情况,蛋白质印迹法和免疫荧光法检测焦亡标记物。结果与对照组相比,中性粒细胞胞外诱捕网刺激后的肺微血管内皮细胞死亡加剧,NLRP3炎症小体和焦亡相关标记物GSDMD、N-GSDMD表达明显升高,NLRP3抑制剂MCC950预处理可有效减弱NLRP3的激活,抑制细胞焦亡的发生。结论中性粒细胞胞外诱捕网可通过激活NLRP3炎症小体诱发人肺微血管内皮细胞焦亡。

水蛭素对缺氧诱导心脏微血管内皮细胞间质转分化的作用及机制研究

目的探讨通络药物水蛭素对缺氧诱导的人心脏微血管内皮细胞(HCMECs)间质转分化(EndMT)的作用及可能机制。方法取常规培养的HCMECs细胞,随机分为对照组、缺氧组、水蛭素组(包括0、20、40、80、100μg/ml 5个浓度)。对照组常规培养不做任何处理,缺氧组置入低氧培养箱72 h,水蛭素组预加入Hirudin工作液,4 h后置入低氧培养箱72 h。MTS比色法检测HCMECs增殖能力;倒置显微镜观察HCMECs形态;免疫荧光鉴定HCMECs间质转分化情况,Western-blot检测内皮间质转分化相关蛋白:包括内皮细胞标记血小板—内皮细胞黏附分子(PECAM-1/CD31)、血管内皮钙黏蛋白(VE-cadherin),间质细胞标记α-平滑肌肌动蛋白(α-SMA)、成纤维细胞特异性蛋白-1(FSP-1),以及低氧诱导因子1α(HIF-1α)、转化生长因子β1(TGF-β1)、Smad同源物2/3(Smad2/3)、锌指转录因子(snail)等相关信号通路的蛋白表达。结果MTS法检测显示,缺氧显著抑制细胞活性(P<0.01),水蛭素在20~100μg/ml浓度范围内可提高细胞活性,且呈现浓度依赖性,当浓度为100μg/ml时细胞活性最强(P<0.01)。各组细胞培养72 h后,倒置显微镜下观察发现:对照组细胞呈铺路石样或鹅卵石状结构,缺氧组细胞由鹅卵石状结构变为分散的长梭形,接近成纤维细胞形态,水蛭素组长梭形细胞形态明显改善,细胞恢复鹅卵石样。Western-blot与免疫荧光结果显示:与对照组比较,缺氧组CD31、VE-cadherin蛋白水平降低(P<0.01),且vWF表达减少,α-SMA、FSP-1蛋白水平升高(P<0.01),且vimentin表达增强;与缺氧组比较,水蛭素明显增加CD31、VE-cadherin蛋白表达(P<0.01),并增强vWF表达,下调α-SMA、FSP-1蛋白表达(P<0.01),并减弱vimentin表达;与对照组相比,缺氧组信号通路HIF-1α、TGF-β1、p-smad2/3、snail蛋白表达均升高(P<0.01),与缺氧组比较,水蛭素下调HIF-1α、TGF-β1、p-smad2/3、snail蛋白表达(P<0.01)。结论水蛭素可以改善缺氧诱导的HCMECs细胞发生EndMT,其机制可能与调控HIF-α/TGF-β1/smad/snail通路有关。

基于网络药理学、分子对接及实验验证探讨滋肾健脾化瘀片对糖尿病视网膜病变的干预机制

目的运用网络药理学方法和分子对接技术探讨滋肾健脾化瘀片(山萸肉、三七、黄芪、葛根、鸡血藤、生地黄)治疗糖尿病视网膜病变(DR)的作用机制,并通过体外实验进行验证。方法(1)利用中药系统药理学数据库与分析平台(TCMSP)及BATMAN-TCM数据库筛选滋肾健脾化瘀片的有效成分及其对应的靶点蛋白。利用GeneCards、OMIM及TTD数据库检索DR疾病相关靶点。利用VENNY 2.1.0平台对药物活性成分靶点与DR疾病相关靶点取交集(共同靶点),即为滋肾健脾化瘀片治疗DR的潜在作用靶点。构建“中药-活性成分-共同靶点”网络,筛选出滋肾健脾化瘀片治疗DR的关键活性成分。将共同靶点导入STRING数据库,获取PPI网络关系,并筛选出核心靶点。运用Metascape平台对共同靶点进行GO功能及KEGG通路富集分析。将关键活性成分及核心靶点通过Autodock 4软件进行分子对接验证。(2)制备滋肾健脾化瘀片含药血清及空白血清。将人视网膜微血管内皮细胞(HRmECs)随机分成5组:对照组(低糖DMEM培养基+10%空白血清)、高糖组(高糖DMEM培养基+10%空白血清)及滋肾健脾化瘀片含药血清低、中、高剂量组(高糖DMEM培养基+10%低、中、高剂量含药血清),培养48 h后进行检测。采用CCK-8法检测HRmECs细胞增殖活性;RT-qPCR法检测HRmECs细胞中IL-1β、AKT1、VEGFA、TP53 mRNA表达水平。结果(1)共筛选出滋肾健脾化瘀片治疗DR的潜在作用靶点(共同靶点)74个;9个关键活性成分包括槲皮素、芒柄花黄素、毛地黄黄酮、β谷甾醇、山柰酚、毛蕊异黄酮、γ-氨基丁酸、豆甾醇、异鼠李亭;12个核心靶点:IL-1β、PPARG、NOS3、CXCL8、IL-6、AKT1、TNF、INS、EGF、VEGFA、TP53、PTGS2。GO功能及KEGG富集分析显示核心靶点主要参与了炎症反应、蛋白质磷酸化的正调控、细胞迁移等生物过程,以及NF-κB信号通路、AGE-RAGE信号通路、HIF-1通路、TNF通路、PI3K-AKT通路等。关键活性成分与核心靶点均具有较好的结合亲和力。(2)与对照组比较,高糖组HRmECs细胞活性显著降低(P<0.01);细胞中VEGFA、TP53、IL-1βmRNA表达水平显著升高(P<0.01),AKT1 mRNA表达水平显著降低(P<0.01)。与高糖组比较,滋肾健脾化瘀片含药血清低、中、高剂量组的HRmECs细胞活性均显著升高(P<0.05,P<0.01),并呈浓度依赖性;含药血清高剂量组细胞的VEGFA、TP53、IL-1βmRNA表达水平显著降低(P<0.05,P<0.01),而AKT1 mRNA表达水平显著升高(P<0.01)。结论滋肾健脾化瘀片可能通过槲皮素、山柰酚、毛地黄黄酮等多种活性成分,作用于IL-1β、IL-6、VEGFA等核心靶点,以及NF-κB信号通路、AGE-RAGE信号通路、PI3K-AKT通路等关键通路,从而发挥对DR的治疗作用。

lncRNA SNHG6对高糖诱导的人视网膜微血管内皮细胞损伤的影响

目的:探讨lncRNA SNHG6对高糖诱导的人视网膜微血管内皮细胞(hRMECs)损伤的影响及其可能的作用机制。方法:采用高糖诱导hRMECs建立细胞损伤模型。高糖(HG)组将hRMECs培养在浓度为25 mmol/L D-葡萄糖的DMEM培养基24 h;正常(NG)组将hRMECs培养在浓度为5.5 mmol/L D-葡萄糖的DMEM培养基;按照实验设计分别将si-NC、si-SNHG6、si-SNHG6和anti-miR-NC、si-SNHG6和anti-miR-186-5p转染至hRMECs,随后25 mmol/L D-葡萄糖孵育24 h,分别记为HG+si-NC组、HG+si-SNHG6组、HG+si-SNHG6+anti-miR-NC组、HG+si-SNHG6+anti-miR-186-5p组。qRT-PCR法检测lncRNA SNHG6、miR-186-5p的表达量;双荧光素酶报告实验检测lncRNA SNHG6与miR-186-5p的靶向关系;MTT法与流式细胞术分别检测细胞增殖及凋亡;ELISA法检测IL-1β、TNF-α、IL-8、IL-10的水平;采用试剂盒检测SOD的活性和MDA的水平;Western blot检测cleaved-caspase3、Bax、Bcl-2蛋白表达量。结果:HG组与NG组比较lncRNA SNHG6表达升高,miR-186-5p表达降低(均P<0.05);lncRNA SNHG6可靶向结合miR-186-5p。转染si-SNHG6后细胞增殖抑制率、凋亡率、cleaved-caspase3、Bax蛋白水平,IL-1β、TNF-α、IL-8含量以及MDA活性降低(P<0.05),而Bcl-2蛋白、IL-10含量以及SOD的活性升高(P<0.05)。共转染si-SNHG6和anti-miR-186-5p后,细胞增殖抑制率、凋亡率、cleaved-caspase3、Bax、IL-1β、TNF-α、IL-8以及MDA升高(P<0.05),而Bcl-2蛋白、IL-10和SOD降低(P<0.05)。结论:干扰lncRNA SNHG6表达可通过促进miR-186-5p表达而抑制高糖诱导的hRMECs凋亡、炎症反应及氧化应激。

RASAL1在同型半胱氨酸致肺血管内皮通透性增加中的作用及机制研究

目的探讨同型半胱氨酸(homocystein,Hcy)对肺微血管内皮细胞(pulmonary microvascular endothelial cells,PMVECs)通透性的影响及Ras蛋白样激活剂(Ras protein activator like,RASAL1)的作用及机制。方法CBS^(+/-)小鼠喂养高蛋氨酸饮食(HMD)16周复制高同型半胱氨酸血症(HHcy)动物模型;HE染色观察肺组织结构变化;qRT-PCR检测肺组织RASAL1、DNMT1 mRNA水平;Western blot检测RASAL1、DNMT1、ZO-1、VE-cadherin蛋白表达;MS-PCR检测RASAL1启动子区甲基化;PMVECs转染Ad-RASAL1检测ZO-1和VE-cadherin表达;si-DNMT1干扰片段转染PMVECs,检测RASAL1表达。结果HMD小鼠血清Hcy水平明显增加,HE染色显示肺组织结构严重紊乱,RASAL1、ZO-1、VE-cadherin表达降低而DNMT1表达增加,RASAL1启动子区甲基化程度增加。PMVECs转染Ad-RASAL1后ZO-1和VE-cadherin表达增加;敲低DNMT1后,RASAL1表达增加。结论Hcy可以导致PMVECs通透性增加,其机制与上调RASAL1甲基化水平有关。

间充质干细胞对肺内皮细胞的保护作用及机制

急性呼吸窘迫综合征(acute respiratory distress syndrome,ARDS)是临床上常见的严重的呼吸衰竭,死亡率高达40%。毛细血管内皮细胞通透性增加和肺水肿是ARDS的重要特征,修复肺微血管内皮屏障是阻止液体和蛋白质进入肺间质和肺泡腔的关键。动物实验和临床试验中发现,间充质干细胞移植可明显改善ARDS,减少炎症反应,降低内皮通透性。静脉移植的间充质干细胞可直接接触内皮细胞,在肺内皮损伤治疗方面可能有独特的优势,其主要通过旁分泌和免疫调节起作用。以往综述大多聚焦间充质干细胞对肺泡上皮的保护作用,本文聚焦肺内皮细胞,综述了间充质干细胞通过旁分泌细胞因子、细胞外囊泡等对内皮的直接保护作用和机制,并分析了间充质干细胞可能通过调节免疫细胞间接保护肺内皮细胞的机制。