由“从瘀论治”理论探讨三七中槲皮素对破骨细胞分化自噬调控机制

目的 探究槲皮素对破骨细胞分化自噬调控机制的影响。方法 本实验分为对照组、RANKL组、RANKL+槲皮素组。通过CCK8检测摸索槲皮素的处理浓度，按照上述分组诱导7 d后进行TRAP染色验证模型成功后，加槲皮素干预48 h进行TRAP染色，通过qPCR检测TRAP、CTSK、NFATC-1、ATG5、p62、mTOR、Beclin-1基因表达。结果 根据CCK8结果选择槲皮素1 mg/L浓度；TRAP染色结果显示RANKL组破骨细胞显著增多，槲皮素干预后破骨细胞减少；qPCR 结果显示模型组TRAP、P62、CTSK、NFATC-1基因表达上升，ATG5、Beclin-1、mTOR基因表达下降，槲皮素干预组TRAP、CTSK、NFATC-1、ATG5、p62、mTOR、Beclin-1基因均下降。电镜观察显示槲皮素干预后破骨细胞自噬小体数量减少。结论 槲皮素可以通过降低自噬基因表达水平抑制破骨细胞的分化。     

五味子乙素调节AMPK/mTOR信号通路对高糖诱导骨髓间充质干细胞功能障碍和自噬的影响

目的 探究五味子乙素（SchB）对高糖（HG）条件下骨髓间充质干细胞（BMSCs）增殖和成骨分化的影响及机制。方法 分离大鼠BMSCs并筛选SchB的实验浓度。将BMSCs分为正常（NC）组、高糖（HG）组、HG+10 μmol/L SchB组、HG+20 μmol/L SchB组、HG+40 μmol/L SchB组、HG+40 μmol/L SchB+AMPK抑制剂Compound C（CC）组。CCK-8法检测细胞活力,碱性磷酸酶（ALP）活性测定和茜素红染色评估BMSCs成骨分化能力;qRT-PCR检测BMSCs中成骨分化相关基因（RUNX2、COl1a1、OCN、BMP2）表达;透射电子显微镜（TEM）观察自噬体数量;Western blot检测自噬（LC3A/B、Beclin-1、P62）,以及AMPK/mTOR信号通路相关蛋白表达。结果 HG环境能抑制BMSCs增殖和成骨分化,并降低自噬体数量、Beclin-1蛋白水平和LC3II/LC3I、p-AMPK/AMPK比值,升高P62蛋白水平和p-mTOR/mTOR比值（均P＜0.05）,抑制AMPK/mTOR通路介导的自噬。SchB可促进HG条件下BMSCs的增殖和成骨分化,并升高自噬体数量、Beclin-1蛋白水平和LC3II/LC3I、p-AMPK/AMPK比值,降低P62蛋白水平和p-mTOR/mTOR比值（均P＜0.05）,激活AMPK/mTOR通路介导的自噬。Compound C可阻断HG条件下SchB对BMSCs增殖、成骨分化和自噬的促进作用。结论 SchB可能通过激活AMPK/mTOR介导的自噬促进HG条件下BMSCs的增殖和成骨分化。     

索拉非尼通过调节Beclin-l的表达诱导肝癌细胞自噬的实验研究

探讨索拉非尼诱导肝癌细胞自噬的作用及机制。选取人肝癌HepG2细胞,随机分为对照组、2.5μmol/L组、5μmol/L组和10μmol/L组,其中2.5μmol/L组、5μmol/L组和10μmol/L组分别给予2.5μmol/L、5μmol/L和10μmol/L索拉非尼,采用MTT法检测细胞增殖,倒置荧光显微镜观察自噬小体,Western blot检测LC3-Ⅱ、Beclin-l表达。2.5μmol/L组、5μmol/L组和10μmol/L组培养24、48和72 h时吸光度(A)值明显低于对照组(P<0.05),其中10μmol/L组培养24、48和72 h时A值分别为0.289±0.097、0.310±0.100和0.411±0.103,明显低于2.5μmol/L和5μmol/L组(P<0.05);2.5μmol/L组、5μmol/L组和10μmol/L组自噬小体形成数明显高于对照组(P<0.05),其中10μmol/L组自噬小体形成数为(37.40±4.45)个,明显高于2.5μmol/L组和5μmol/L组(P<0.05);2.5μmol/L、5μmol/L组和10μmol/L组LC3-Ⅱ、Beclin-1相对表达量明显高于对照组(P<0.05),其中10μmol/L组LC3-Ⅱ、Beclin-1相对表达量为1.022±0.105和0.562±0.102,明显高于2.5μmol/L组和5μmol/L组(P<0.05)。索拉非尼可抑制肝癌细胞增殖,促进自噬小体生成,可能与调控Beclin-1表达有关。     

基质细胞衍生因子-1对小鼠关节软骨细胞自噬水平的影响

目的：通过研究基质细胞衍生因子-1（stromal derived factor?1, SDF?1）对小鼠关节软骨细胞自噬的影响,探讨SDF?1在骨性关节炎中的作用及机制。方法分离并体外培养小鼠关节软骨细胞,分别予以0、1、10、100、1000μg/L浓度的五组重组SDF?1蛋白干预24 h。运用RT?PCR检测各组细胞的微管相关蛋白1轻链3（microtubule associated protein 1 light chain 3, LC3）和UNC?51样激酶复合物1（uncoordinated?51 like kinase 1, ULK1）mRNA表达情况,运用Western Blot方法检测LC3?Ⅱ、LC3?Ⅰ、ULK1及泛素连接蛋白62（ubiquitin?binding protein p62, p62）蛋白表达水平,通过透射电镜观察自噬溶酶体。结果 RT?PCR结果显示10、100、1000μg/L浓度条件下LC3、ULK1的mRNA水平明显高于对照组,且差异具有统计学意义（P＜0.05）。Western Blot结果显示1、10、100、1000μg/L的各组细胞的LC3?Ⅱ/LC3?Ⅰ比值、ULK?1表达水平较对照组升高,p62蛋白表达水平较对照组明显降低,差异具有统计学意义（P＜0.05）。透射电镜结果显示经SDF?1干预后,自噬溶酶体较对照组增多,差异具有统计学意义（P＜0.05）。结论 SDF?1可诱导小鼠关节软骨细胞自噬的发生,SDF?1可能通过调节软骨细胞自噬水平参与了骨性关节炎的进展。     

肝X受体激动剂GW3965对人结肠癌细胞奥沙利铂耐药的逆转作用及机制

目的:探讨肝X受体(LXR)激动剂GW3965对人结肠癌细胞奥沙利铂(OXA)耐药的逆转作用及机制。方法:用OXA药物浓度持续递增法诱导人结肠癌HCT116细胞构建OXA耐药的人结肠癌HCT116/L-OHP细胞,比较HCT116/L-OHP细胞与其亲本HCT116细胞的生长情况,以及对不同浓度OXA作用的反应情况;检测HCT116/L-OHP细胞经GW3965处理48 h后OXA耐药性及自噬相关蛋白ATG-5、Beclin-1、p62、LC3的表达的变化。结果:成功构建人结肠癌耐OXA细胞HCT116/L-OHP,表现为HCT116/L-OHP细胞与亲本HCT116细胞比较,增殖能力有所减弱,但对OXA的耐药性明显增强(IC_(50):244.99μmol/L vs.10.05μmol/L,P0.05),其耐药指数(RI)为24.45。不同浓度(10、20、30μmol/L)GW3965作用后,HCT116/L-OHP细胞对OXA的IC_(50)、RI均明显降低(均P0.05),且呈浓度依赖性(IC_(50):199.49、114.71、87.32μmol/L;RI:19.89、11.40、8.69),3个浓度的逆转倍数分别为1.23、2.15、2.82;ATG-5、Beclin-1蛋白的表达明显降低,而p62、LC3-II蛋白的表达明显升高(均P0.05),且均呈浓度依赖性。结论:LXR激动剂GW3965可逆转人结肠癌细胞对OXA的耐药,其机制可能与调节自噬相关蛋白表达水平有关。     

体外研究橙皮苷抑制钛颗粒介导的破骨细胞分化

目的研究橙皮苷对钛颗粒介导前破骨细胞分化及成熟的影响。 方法骨髓巨噬细胞在巨噬细胞集落刺激因子(M-CSF)30 ng/ml及核因子κB受体活化因子配体(Rankl)50 ng/ml刺激下,诱导分化为破骨细胞。扫描电镜观察钛磨损颗粒形貌结构。对不同浓度下橙皮苷对巨噬细胞增殖的影响进行t检验分析得出最低有效浓度;对抗酒石酸酸性磷酸酶(TRAP)阳性细胞数及骨吸收陷窝面积判断橙皮苷对破骨细胞分化及成熟的影响。最后通过实时定量PCR(RT-PCR)验证橙皮苷对钛颗粒介导的破骨基因,包括活化T细胞核因子(NFATc1)、组织蛋白酶K (CTSK)、TRAP的影响。TRAP阳性细胞数及骨吸收陷窝面积、RT-PCR结果数据均采用t检验分析。 结果扫描电镜显示钛磨损颗粒大小在1～3 μm。CCK-8实验结果显示橙皮苷对巨噬细胞增殖有促进作用,浓度超过40 μmol/L后,会对巨噬细胞产生抑制作用(F＝40.1, P<0.01),所以选择40 μmol/L作为对巨噬细胞分化的影响。在抗酒石酸酸性磷酸酶染色中发现40 μmol/L的橙皮苷会明显抑制前破骨细胞的分化,TRAP阳性细胞数目及破骨细胞的面积明显减少(t＝5.5,P<0.05)。与对照组相比,扫描电镜观察钛颗粒介导骨吸收陷窝面积明显增多,但加入40 μmol/L的橙皮苷后,这种吸收效果或明显减少(t＝6.1,P<0.05)。最后,通过RT-PCR实验得出,40 μmol/L的橙皮苷会明显抑制破骨细胞分化相关NFATc1, CTSK,TRAP基因(t＝7.1、4.8、9.1,均为P<0.05)。 结论橙皮苷抑制钛颗粒介导的破骨细胞分化及成熟。     

番茄红素对高糖诱导的足细胞自噬以及凋亡的影响

目的探讨番茄红素(Lyc)对高糖诱导的足细胞自噬及凋亡的影响,旨在为临床治疗糖尿病肾病提供可靠的理论依据。方法采用条件永生化小鼠足细胞系为研究对象,通过添加不同剂量的Lyc对高糖诱导的足细胞进行干预。实验细胞分6组,分别为正常对照组(5.5m m ol/L葡萄糖)、高渗对照组(5.5 m m ol/L葡萄糖+1 9.5 m m ol/L甘露醇)、高糖组(2 5 m m ol/L葡萄糖)、低剂量Lyc组(25 mmol/L葡萄糖+3.125μmol/L Lyc)、中剂量Lyc组(25 mmol/L葡萄糖+6.25μmol/L Lyc)和高剂量Lyc组(25 mmol/L葡萄糖+12.5μmol/L Lyc)。在细胞培养4 8 h后,用吖啶橙染色法观察各组细胞的自噬体变化情况;流式细胞技术检测各组细胞的凋亡率变化;采用实时定量荧光PCR和蛋白质印迹法分别检测自噬相关基因LC3、beclin-1、p62/SQSTM I m RNA和蛋白的表达变化情况。结果与正常对照组、高渗对照组相比,高糖组细胞中的自噬体数目明显增多,细胞的凋亡率极显著增加(P0.01),自噬相关基因LC3-II、beclin-1的表达量显著增加(P0.05),而p62/SQSTMI基因的表达量则显著降低(P0.05)。与高糖组比较,不同剂量Lyc组中的足细胞自噬体数目更多;细胞的凋亡率显著降低(P0.05),且高剂量Lyc组细胞的凋亡率降低极显著(P0.01);自噬相关基因LC3-II、beclin-1表达量显著增加(P0.05);而p62/SQSTMI基因表达量则显著降低(P0.05);且高剂量Lyc组基因表达量变化极显著(P0.01);蛋白水平上的检测结果与mRNA水平基本一致。结论Lyc能进一步增强高糖诱导引起的足细胞的自噬,但对足细胞的凋亡却起到了一定的抑制作用,且高剂量的Lyc作用效果更加明显。     

自噬在镉致小鼠睾丸血-睾屏障损伤中的作用

目的:探究自噬在氯化镉致小鼠睾丸血-睾屏障(BTB)损伤中的作用。方法:将20只4周龄雄性C57BL/6小鼠随机分为对照组[0 mg/(kg·d)]、低剂量组[0.5 mg/(kg·d)]、中剂量组[1.0 mg/(kg·d)]和高剂量组[2.0 mg/(kg·d)],腹腔注射氯化镉，连续28 d。采用HE染色法分析睾丸组织形态学变化，生物示踪法观察BTB的完整性，Western印迹检测BTB组分ZO-1和N-Cadherin蛋白的表达。采用0、2.5、5和10μmol/L CdCl₂处理睾丸支持细胞株(TM4细胞)24 h, Western印迹检测ZO-1和N-Cadherin蛋白，以及自噬相关蛋白LC3II和p62的变化情况。在含CdCl₂(10μmol/L)的细胞培养液中分别加入自噬抑制剂氯喹(CQ)(5μmol/L)或自噬激动剂雷帕霉素(Rap)(50 nmol/L)处理细胞24 h, Western印迹检测LC3II、p62、ZO-1和N-Cadherin蛋白表达。结果:与对照组小鼠相比，镉染毒组小鼠的生精小管间隙增大、生精细胞内空...     

狼疮肾炎患者自噬水平及其对足细胞相关蛋白表达水平的影响

目的探讨狼疮肾炎(lupus nephritis,LN)患者自噬水平及其对足细胞相关蛋白表达水平的影响。方法选择2017年5月至2019年5月于榆林市第一医院收治的69例LN患者为LN组,50例系统性红斑狼疮(systemic lupus erythematosus,SLE)患者为SLE组,50例肾切除手术患者为对照组,观察3组肾脏足细胞内自噬体数量,比较3组肾脏组织中自噬相关蛋白、微管相关蛋白轻链3(LC3)、B淋巴细胞瘤蛋白质-2-相互作用蛋白(Beclin1)的表达,以及足细胞相关蛋白,肾病蛋白(Nephrin)、足突蛋白(Podocin)的表达。分离狼疮肾炎患者肾脏足细胞,将足细胞分为自噬抑制组和自噬诱导组,自噬抑制组加入100 nmol/L 3-甲基腺嘌呤(3-MA),自噬诱导组加入100 nmol/L雷帕霉素(RAPA),比较3组足细胞内自噬体数量及LC3、Beclin-1、Podocin、Nephrin等蛋白的表达。结果LN组、SLE组肾脏足细胞内自噬体数量及LC3、Beclin-1、Podocin、Nephrin蛋白表达量显著高于对照组(P<0.05);SLE组肾脏足细胞内自噬体数量及LC3、Beclin-1、Podocin、Nephrin蛋白表达量显著高于LN组(P<0.05);自噬诱导组足细胞内自噬体数量及LC3、Beclin-1、Podocin、Nephrin蛋白表达量显著高于正常对照组、自噬抑制组(P<0.05);正常对照组足细胞内自噬体数量及LC3、Beclin-1、Podocin、Nephrin蛋白表达量显著高于自噬抑制组(P<0.05)。结论LN患者自噬水平呈升高状态,自噬水平升高可能通过上调足细胞相关蛋白Podocin、Nephrin水平而减轻足细胞损伤,抑制LN病情进展。     

艾拉莫德对类风湿关节炎外周血破骨细胞分化及破骨细胞相关基因表达的影响

目的观察艾拉莫德对类风湿关节炎(rheumatoid arthritis,RA)外周血破骨细胞分化形成及破骨细胞相关基因表达的影响。方法使用人核因子kB受体活化因子配体(receptor activator of nuclear factor-κB ligand,RANKL)及人巨噬细胞集落刺激因子(macrophage colony-stimulating factor,M-CSF)诱导RA患者外周血淋巴细胞(Peripheral blood mononuclear cell,PBMCs)分化为成熟破骨细胞,抗酒石酸酸性磷酸酶(tartrate-resistant acid phosphatase,TRAP)染色进行鉴定。CCK-8法筛选艾拉莫德抑制破骨细胞形成的浓度。观察艾拉莫德25μg/mL、12.5μg/mL、6.25μg/mL对RA患者PBMCs生成破骨细胞的影响,RT-PCR法检测不同浓度艾拉莫德对破骨细胞分化过程中TRAP、组织蛋白酶K(Cathepsin K,CTSK)、细胞核因子κB受体活化因子(receptor activator of nuclear factor-κB,RANK)、激活蛋白-1(Activator protein-1,AP-1)mRNA表达的影响。结果 100 ng/mL RANKL和50 ng/mL M-CSF在第14天将RA患者PBMCs诱导为破骨细胞。CCK-8检测结果显示艾拉莫德25μg/mL、12.5μg/mL、6.25μg/mL三个浓度对PBMCs细胞活力无明显影响,且均能抑制破骨细胞的生成,以25μg/mL组最为显著。艾拉莫德能抑制TRAP、CTSK、RANK、AP-1 mRNA的表达水平,且随艾拉莫德浓度的升高抑制作用越明显。结论艾拉莫德通过抑制破骨细胞特异性基因表达来抑制破骨细胞分化、增殖。     

Dynamic changes of autophagy during hypertrophic scar formation and the role of autophagy intervention

BackgroundThe role of autophagy in the formation of hypertrophic scars (HS) remains unclear. This study aimed to explore the role and potential mechanism of autophagy during the development of HS.MethodsRNA and protein expression levels of Beclin-1, p62, and LC3II in normal skin tissues and HS specimens from different patients were examined. Autophagy inducers and inhibitors were used to cure established HS in rabbit ears, and the expression of Beclin-1, p62, and LC3II at the RNA and protein level was determined. Lastly, the effects of autophagy inducers and inhibitors on HS development were analyzed.ResultsCompared to normal skin tissues, the expression of LC3Ⅱ and Beclin-1 was higher (P<0.05), while that of p62 was lower (P<0.05) in HS tissues. In addition, the LC3II/LC3I ratio was increased during HS formation, and the altered expression of the three proteins stabilized after one year. Administration of autophagy inducers enhanced the formation of HS as well as the expression levels of LC3II and Beclin-1 but decreased p62 expression. Meanwhile, administration of autophagy inhibitors increased the expression of LC3II, Beclin-1, and p62, along with reduced HS formation.ConclusionAutophagic activity increased during HS initiation and subsequent stabilization. In addition, autophagy inhibitors were able to inhibit HS formation by suppressing autophagy, whereas autophagy inducers promoted scar hyperplasia by enhancing autophagy.     

Role of autophagy in contrast media-induced renal tubular epithelial cells injury

Objective To observe the effect of contrast media on autophagy and apoptosis of renal tubular epithelial cells, evaluate the role of autophagy in contrast media-induced renal tubular epithelial cells injury. Methods NRK-52E cells were exposed to iopromide at different concentration for 1 hour or at 50 gI/L for variable incubation time. Rapamycin (1 μg/L) and 3-methyadenine (2 mmol/L) were further introduced to investigate the role of autophagy in the process. The formation of autophagy was observed by acridine orange staining and Green fluorescent protein tagged LC3 (GFP-LC3). The expression of autophagy protein LC3 and Beclin-1 was examined by Western blotting, and the apoptosis level was examined by flow cytometry and Hoechst 33342-staining. Results (1) Autophagy could be enhanced by contrast media in renal tubular epithelial cells. (2) The expression of LC3-Ⅱ/LC3-I in renal tubular epithelial cells rose at first and then dropped with the increase of iopromide stimulation time and concentration (P＜0.05). (3) Iopromide promoted renal tubular epithelial cell apoptosis in dose-and time-dependent manner (P＜0.05). (4) Co-culture with rapamycin further increased LC3-Ⅱ/LC3-I, Beclin-1 and GFP-LC3 expression, but obviously prevented iopromide-induced apoptosis of renal tubular epithelial cells (P＜0.05). On the contrary, Co-culture with 3-methyadenine reduced iopromide-induced LC3-II/LC3-I, Beclin-1 and GFP-LC3 overexpression, but aggravated the apoptosis induced by iopromide (P＜0.05). Conclusions Contrast media can induce renal tubular epithelial cells apoptosis as well as autophagy. Enhancing autophagy appropriately has a protective effect on iopromide-induced renal tubular epithelial cells apoptosis, which conforms that autophagy plays an important role in antagonizing iopromide-induced renal tubular epithelial cells injury.     

高糖通过PI3K-AKT-mTOR信号通路增加足细胞自噬

目的 研究高糖引起足细胞自噬变化及其相关的信号机制.方法 培养的足细胞被分为6组,正常浓度葡萄糖(NG)组、高浓度葡萄糖(HG)组、NG+雷帕霉素(Rap)组、HG+Rap组、NG+LY294002组和HG+LY294002组.观察自噬增强剂Rap和PI3K抑制剂LY294002对高糖条件下培养的足细胞自噬和凋亡的影响.电镜和吖啶橙染色观察细胞内自噬体的形成;Western印迹检测自噬标志蛋白微管相关蛋白1轻链3(LC3)和自噬血管基因Beclin-1的表达;通过阻断自噬的信号通路观察磷脂酰肌醇3激酶-蛋白激酶B-哺乳动物雷帕霉素靶蛋白(PI3K-AKT-mTOR)相关蛋白AKT和mTOR的磷酸化水平的改变.结果 高糖可导致足细胞凋亡增加,促进足细胞内自噬体和自噬相关蛋白表达增加(均P＜ 0.05).与高糖组相比,HG+ Rap组LC3-Ⅱ和Beclin-1的表达增加(均P＜0.05);LY294002部分抑制高糖导致的LC3-Ⅱ和Beclin-1表达增加(均P＜0.05).与高糖组相比,HG+ LY294002组足细胞内AKT磷酸化的水平增加(P＜0.05),mTOR的磷酸化水平降低(P＜0.01);HG+ LY294002组足细胞的AKT和mTOR磷酸化水平较高糖组均降低(均P＜0.05).结论 高糖可促进足细胞的自噬和凋亡,推测高糖诱导的足细胞自噬作用部分通过PI3K-AKT-mTOR信号通路调节实现的.     

Autophagy alleviate podocytes injury induced by contrast media via oxidative stress

Objective To evaluate the effects of autophagy on oxidative stress induced by contrast media in podocytes. Methods The differentiated mouse podocytes were exposed to contrast media (Iopromide, 50 mg/L)、rapamycin (Rap, autophagy enhancer, 1 ng/L), 3-methyladenine (3-MA, autophagy inhibitor, 2 mmol/L) for 2 hours. The expression of autophagy protein LC3-Ⅱand Beclin-1 as well as oxidative stress-related proteins Catalase, MnSOD were detected by Western blot. The formations of autophagy were observed by MDC staining, and the levels of reactive oxygen species (ROS) by CM-H2DCFDA staining. Cell activity was evaluated by CCK8 assay. Results Both the levels of oxidative stress and autophagy in podocytes increased when stimulated by contrast media, the expression of LC3-Ⅱand Beclin-1 were enhanced, Catalase and MnSOD were inhibited (all P＜0.05). Rapamycin increased the expression of Catalase, MnSOD and cell activity of podocytes, reduced the generation of ROS (all P＜0.05), but in Rap group, cell activity showed no significant difference (P＞0.05). 3-MA decreased the expression of Catalase、 MnSOD and inhibited the cell activity of podocyte, increased the generation of ROS (all P＜0.05). Conclusion Autophagy protects podocyte from contrast media by the means of reducing oxidative stress.     

Aurora A激酶抑制剂Alisertib诱导结直肠癌细胞自噬的作用及与p53表达间的关系

目的 探讨Alisertib（ALS）对人结直肠癌Caco-2和HT29细胞的诱导自噬的作用及与p53 表达状态间的关系。方法 本研究采用人结直肠癌Caco-2和HT29细胞进行实验。实验组用0.1、1、5 μmol/L ALS而对照组用同浓度的DMSO处理细胞。流式细胞术检测细胞的自噬率,Wester Blotting法检测细胞自噬过程中关键调节分子的蛋白表达。结果与对照组比较,0.1、1 μmol/L Alisertib组Caco-2细胞自噬率增加,分别为26.4%和26.8%（P<0.01）。1、5 μmol/L ALS组HT29细胞自噬率增加,分别为36.8%和42.6%（P<0.01）。Caco-2细胞不表达p53蛋白,而HT29细胞表达p53蛋白。与对照组比较,1、5μmol/L Alisertib引起Caco-2细胞的p-PI3K/PI3K、p-Akt/Akt和p-p38/p38的比值分别降低为对照组的62.6%、45.2%,30.1%、38.2%和49.0%、30.4%（P<0.01）,LC3-Ⅱ/LC3-I的比值升高32.6%、46.8%（P<0.01）。与对照组比较,1、5 μmol/L Alisertib引起HT29细胞的p-PI3K/PI3K、p-Akt/Akt的比值分别降低为对照组的70.9%、66.3%和85.2%、27.2%（P<0.01）,p-p38/p38和LC3-II/LC3-I的比值升高2.1倍、2.0倍和78.5%、84.8%（P<0.05）。与5 μmol/L Alisertib组比较,10 μmol/L SB202190+5 μmol/L Alisertib引起HT29细胞凋亡率升高64.7%（P<0.001）,而Caco-2细胞凋亡率无明显变化。结论 Alisertib抑制了PI3K/Akt信号通路,诱导了Caco-2和HT29细胞发生细胞自噬。Alisertib对p38 MAPK信号通路的影响不同,激活了HT29而抑制了Caco-2细胞的p38 MAPK信号通路,可能与p53蛋白是否表达有关。     

Role of autophagy in high glucose-induced podocyte lipid droplet accumulation

Objective To investigate the role of autophagy in high glucose-induced podocyte lipid droplet metabolism. Methods (1) Cultured, conditionally immortalized human podocytes (HPC) were divided into normal control group, high glucose group and mannitol group. Oil red O staining and oil red O staining extraction assay was used to observe the degree of lipid accumulation; Protein level of SREBP-1 was analyzed by Western blotting. (2) HPC were cultured and divided into normal control group, high glucose group, high glucose+3-methyladenine (3-MA) group, and mannitol group. Acridine orange staining was used to observe the formation of autophagosomes. Western blotting was used to detect the protein levels of beclin-1 and LC3-II/LC3-I. Oil red O staining and oil red O staining extraction assay was used to observe the degree of lipid accumulation; Western blotting was used to analyze the expression of SREBP-1. Results (1) Compared with the normal control group, the lipid accumulation in the high glucose group was increased and the lipid metabolism related molecule SREBP-1 was up-regulated (P＜0.05); There was no significant difference between the normal control group and the mannitol group in lipid accumulation (P＞0.05). (2) Compared with the normal group, the number of autophagosomes was increased and autophagy-related proteins beclin-1 and LC3-II/LC3-I were up-regulated in high glucose group (all P＜0.05). After intervened with 3-methyladenine, a significant decrease in autophagosomes was observed; Protein levels of autophagy-related proteins beclin-1 and LC3-II/LC3-I were decreased (all P＜0.05); The lipid droplets in the high glucose+3-MA group was decreased and lipid metabolism related molecule SREBP-1 was down-regulated (all P＜0.05). Conclusion Autophagy may be involved in the process of high-glucose-induced podocyte lipid accumulation by affecting SREBP-1 expression, and inhibition of autophagy can alleviate the high-glucose-induced podocyte lipid accumulation.