白花丹素介导sirt1-FOXO1通路对糖尿病肾病大鼠氧化应激损伤的影响

目的探究白花丹素通过沉默信息调节因子2相关酶(sirt)1-叉头框蛋白(FOX)O1通路对糖尿病肾病(DN)大鼠氧化应激损伤的影响。方法120只SD大鼠随机分为对照组、DN组、白花丹素低剂量组、白花丹素高剂量组、EX-527组(sirt1抑制剂,5 mg/kg)、白花丹素高剂量+EX-527组,每组20只。检测大鼠24 h尿蛋白、空腹血糖(FBG)、血肌酐(SCr)、血β2微球蛋白(β2-MG)及肾组织匀浆中超氧化物歧化酶(SOD)、丙二醛(MDA)、过氧化氢酶(CAT)、白细胞介素(IL)-1β、IL-6水平;测定大鼠左肾指数;过碘酸雪夫(PAS)染色观测肾脏病理变化;TUNEL法检测肾组织细胞凋亡;Western印迹法检测sirt1-FOXO1通路相关蛋白表达。结果与对照组相比,DN组24 h尿蛋白、FBG、Scr、β2-MG水平、左肾指数、MDA、IL-1β、IL-6水平均显著升高,肾组织匀浆SOD、CAT水平、肾组织sirt1、FOXO1蛋白均显著降低(P<0.05)。与DN组相比,白花丹素低、高剂量组24 h尿蛋白、FBG、Scr、β2-MG水平、左肾指数、MDA、IL-1β、IL-6水平均显著降低,肾组织匀浆SOD、CAT水平、肾组织sirt1、FOXO1蛋白显著升高(P<0.05);EX-527组24 h尿蛋白、FBG、Scr、β2-MG水平、左肾指数、MDA、IL-1β、IL-6水平均显著升高,肾组织匀浆SOD、CAT水平、肾组织sirt1、FOXO1蛋白均显著降低(P<0.05);EX-527可部分削弱白花丹素高剂量对DN大鼠氧化应激损伤的缓解作用。结论白花丹素可能通过激活sirt1-FOXO1通路,缓解DN大鼠氧化应激损伤。

Corilagin alleviates podocyte injury in diabetic nephropathy by regulating autophagy via the SIRT1-AMPK pathway

BACKGROUND Diabetic nephropathy(DN)is the most frequent chronic microvascular consequence of diabetes,and podocyte injury and malfunction are closely related to the development of DN.Studies have shown that corilagin(Cor)has hepatoprotective,anti-inflammatory,antibacterial,antioxidant,anti-hypertensive,antidiabetic,and anti-tumor activities.AIM To explore the protective effect of Cor against podocyte injury in DN mice and the underlying mechanisms.METHODS Streptozotocin and a high-fat diet were combined to generate DN mice models,which were then divided into either a Cor group or a DN group(n=8 in each group).Mice in the Cor group were intraperitoneally injected with Cor(30 mg/kg/d)for 12 wk,and mice in the DN group were treated with saline.Biochemical analysis was used to measure the blood lipid profiles.Hematoxylin and eosin staining was used to detect pathological changes in kidney tissue.Immunohistochemistry and Western blotting were used to assess the protein expression of nephrin and podocin.Mouse podocyte cells(MPC5)were cultured and treated with glucose(5 mmol/L),Cor(50μM),high glucose(HG)(30 mmol/L),and HG(30 mmol/L)plus Cor(50μM).Real-time quantitative PCR and Western blotting RESULTS Compared with the control group,the DN mice models had increased fasting blood glucose,glycosylated hemoglobin,triglycerides,and total cholesterol,decreased nephrin and podocin expression,increased apoptosis rate,elevated inflammatory cytokines,and enhanced oxidative stress.All of the conditions mentioned above were alleviated after intervention with Cor.In addition,Cor therapy improved SIRT1 and AMPK expression(P<0.001),inhibited reactive oxygen species and oxidative stress,and elevated autophagy in HG-induced podocytes(P<0.01).CONCLUSION Cor alleviates podocyte injury by regulating autophagy via the SIRT1-AMPK pathway,thereby exerting its protective impact on renal function in DN mice.

基于SIRT1/FOXO3a信号通路探讨“温阳通脉”灸法对ApoE^(-/-)动脉粥样硬化小鼠炎症反应的影响

【目的】探讨“温阳通脉”灸法防治动脉粥样硬化(AS)的作用机制。【方法】将10只饲喂普通饲料的C57BL/6J小鼠设为空白组;将30只ApoE^(-/-)小鼠给予高脂饲料喂养建立动脉粥样硬化模型,随机分为模型组、辛伐他汀组和艾灸组,每组10只。于造模第1天开始干预,艾灸组小鼠给予膻中、神阙、内关、血海穴艾灸,辛伐他汀组给予辛伐他汀蒸馏水混悬液灌胃,共干预12周。给药结束后,采用苏木素-伊红(HE)染色法观察小鼠胸主动脉病理形态结构,透射电镜观察小鼠胸主动脉内皮细胞超微结构,酶联免疫吸附法(ELISA)检测小鼠血清肿瘤坏死因子α(TNF-α)、细胞间黏附分子1(ICAM-1)、血管细胞黏附分子1(VCAM-1)水平,实时定量聚合酶链反应(qRT-PCR)法检测胸主动脉沉默信息调节因子1(SIRT1)和叉头框转录因子O3a(FOXO3a)的mRNA表达水平,Western Blot法检测胸主动脉SIRT1和FOXO3a蛋白表达水平。【结果】与空白组比较,模型组小鼠胸主动脉及血管内皮细胞病理变化明显,血清炎症因子TNF-α、ICAM-1和VCAM-1水平升高(P<0.05或P<0.01),胸主动脉SIRT1 mRNA和蛋白表达量降低(P<0.01),FOXO3a mRNA和蛋白表达量差异无统计学意义(P>0.05);与模型组比较,辛伐他汀组和艾灸组小鼠的胸主动脉及血管内皮细胞结构得到明显改善,血清TNF-α、ICAM-1、VCAM-1水平均降低(P<0.05),胸主动脉SIRT1 mRNA和蛋白表达量增加(P<0.05或P<0.01),FOXO3a mRNA和蛋白表达量差异均无统计学意义(P>0.05)。辛伐他汀组和艾灸组上述指标组间比较,差异均无统计学意义(P>0.05)。【结论】“温阳通脉”灸法可通过调控SIRT1/FOXO3a信号通路减轻炎症反应防治小鼠AS。

川芎嗪对脂多糖诱导内皮细胞凋亡及Sirt1/FoxO1通路的影响

目的研究川芎嗪(tetramethylpyrazine,TMP)对脂多糖(LPS)诱导内皮细胞凋亡及沉默信息调节因子1/叉头转录因子O1(SIRT1/Fox O1)通路的影响。方法培养人脐静脉内皮细胞(HUVECs)并分为对照组、LPS组和TMP组。对照组用不含药物的DMEM处理,LPS组用含有10μg/ml LPS的DMEM处理,TMP组用含有含有10μg/ml LPS及不同浓度TMP(10-10,10-12,10-14mol/L)的DMEM处理,检测细胞活力、凋亡率、凋亡基因及Sirt1/Fox O1通路分子的表达。结果与对照组比较,LPS组HUVECs的细胞活力及Bcl-2、乙酰化-Fox O1的蛋白表达明显降低,凋亡率及Bax、Caspase-9、Caspase-3、Sirt1的蛋白表达量明显增加(P<0.05);与LPS组比较,10-10,10-12,10-14mol/L TMP组的细胞活力明显增加、凋亡率明显降低(P<0.05),且TMP浓度越高,细胞活力的增加及凋亡率的降低越明显(P<0.05);与LPS组比较,10-10mol/L TMP组的Bax、Caspase-9、Caspase-3、Sirt1的蛋白表达量明显增加,Bcl-2、乙酰化-Fox O1的蛋白表达量明显减少(P<0.05),Fox O1的蛋白表达量无明显变化(P>0.05)。结论TMP对LPS诱导内皮细胞凋亡具有抑制作用,且该作用可能与Sirt1/Fox O1通路的抑制有关。

Huangqin decoction alleviates lipid metabolism disorders and insulin resistance in nonalcoholic fatty liver disease by triggering Sirt1/NF-κB pathway

BACKGROUND Nonalcoholic fatty liver disease(NAFLD)is a clinicopathological entity characterized by intrahepatic ectopic steatosis.As a consequence of increased consumption of high-calorie diet and adoption of a sedentary lifestyle,the incidence of NAFLD has surpassed that of viral hepatitis,making it the most common cause of chronic liver disease globally.Huangqin decoction(HQD),a Chinese medicinal formulation that has been used clinically for thousands of years,has beneficial outcomes in patients with liver diseases,including NAFLD.However,the role and mechanism of action of HQD in lipid metabolism disorders and insulin resistance in NAFLD remain poorly understood.AIM To evaluate the ameliorative effects of HQD in NAFLD,with a focus on lipid metabolism and insulin resistance,and to elucidate the underlying mechanism of action.METHODS High-fat diet-induced NAFLD rats and palmitic acid(PA)-stimulated HepG2 cells were used to investigate the effects of HQD and identify its potential mechanism of action.Phytochemicals in HQD were analyzed by highperformance liquid chromatography(HPLC)to identify the key components.RESULTS Ten primary chemical components of HQD were identified by HPLC analysis.In vivo,HQD effectively prevented rats from gaining body and liver weight,improved the liver index,ameliorated hepatic histological aberrations,decreased transaminase and lipid profile disorders,and reduced the levels of pro-inflammatory factors and insulin resistance.In vitro studies revealed that HQD effectively alleviated PA-induced lipid accumulation,inflammation,and insulin resistance in HepG2 cells.In-depth investigation revealed that HQD triggers Sirt1/NF-κB pathwaymodulated lipogenesis and inflammation,contributing to its beneficial actions,which was further corroborated by the addition of the Sirt1 antagonist EX-527 that compromised the favorable effects of HQD.CONCLUSION In summary,our study confirmed that HQD mitigates lipid metabolism disorders and insulin resistance in NAFLD by triggering the Sirt1/NF-κB pathway.

CHANGES IN NEUROPEPTIDES AFTER MUSIC EXPOSURE 429Cardioprotective effect of ivabradine via the AMPK/SIRT1/PGC-1αsignaling pathway in myocardial ischemia/reperfusion injuryinduced in H9c2 cell

Post-resuscitation myocardial dysfunction(PRMD)is the most severe myocardial ischemia-reperfusion injury(MIRI)and is characterized by difficult treatment and poor prognosis.Research has shown the protective effects of the rational use of ivabradine(IVA)against PRMD,however,the molecular mechanisms of IVA remain unknown.In this study,an ischemia-reperfusion injury(IRI)model was established using hypoxic chambers.The results demonstrated that pretreatment with IVA reduced IRI-induced cytotoxicity and apoptosis.IVA attenuated mitochondrial damage,eliminated excess reactive oxygen species(ROS),suppressed IRI-induced ATP and NAD+,and increased the AMP/ATP ratio.We further found that IVA increased the mRNA levels of sirtuin 1(SIRT1)and peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α)and upregulated the expression levels of phosphorylated AMP-activated protein kinase(p-AMPK)/AMPK,SIRT1,and PGC-1αproteins.Interestingly,no change in AMPK mRNA levels was observed.Cardiomyocyte energy metabolism significantly changed after IRI.The aim of this study was to demonstrate the cardioprotective effect of Ivabradine via the AMPK/SIRT1/PGC-1αsignaling pathway in myocardial ischemia/reperfusion injury-induced in H9c2 cell.

Mechanism of Resveratrol on autophagy mediated by Mst1/Sirt3 signaling pathway in diabetic cardiomyopathy

Objective:To observe the effects of resveratrol on myocardial cell injury and Mst1/Sirt3 signaling pathway mediated autophagy in type 2 diabetic mice. Methods:C57 BL/KSJ db/db mice were allocated to the normal control group,the model group,and the resveratrol group;C57 BL/KSJ db/m mice served as the melbine group,with 10 mice each. The resveratrol group and the melbine group were treated with resveratrol and metformin by gavage,respectively. The normal control group and the model group were treated with equal volume of normal saline by gavage,for 8 consecutive weeks. H & E staining,transmission electron microscopy and immunofluorescence were used to observe the pathological morphology,ultrastructure and apoptosis levels of myocardial tissues,respectively. RT-qPCR method was used to detect the expression levels of apoptosis genes Bax and Bcl-2 in myocardial tissues,and Western-blot method was used to detect the expression levels of autophagy proteins(LC3 and p62),Mst1 and Sirt3 proteins in myocardial tissue. Results:Compared with the model group,resveratrol can significantly reduce the body weight,blood glucose level and serum CK and LDH levels of db/db mice,and the differences were statistically significant(P<0.05;P<0.01). Meanwhile,after resveratrol treatment,myocardial inflammation score,apoptosis rate,Bax mRNA expression level and Bax/Bcl-2 ratio in myocardial tissue were significantly reduced,and Bcl-2 mRNA expression level was significantly increased,and the differences were statistically significant(P<0.01). In addition,compared with the model group,the expression level of p62 and p-Mst1 protein in the myocardial tissue of the resveratrol group was significantly reduced,and the expression level of Sirt3 protein and the ratio of LC3Ⅱ/LC3Ⅰ were significantly increased,and the differences were statistically significant(P<0.01). Conclusion:Resveratrol promotes the autophagy level of cardiomyocytes by activating the Mst1/Sirt3 signaling pathway and inhibits cardiomyocyte apoptosis to play a protective role in diabetic cardiomyopathy.

Mechanism of hesperidin improving myocardial ischemia/reperfusion injury in type 2 diabetic rats through SIRT1/Nrf2/HO-1 signaling pathway

Objective:To observe the protective effect of hesperidin on myocardial ischemia/reperfusion injury in type 2 diabetes mellitus and its effect on SIRT1/Nrf2/HO-1 signaling pathway.Methods:50 Sprague-Dawley(SD)rats were randomly assigned to the normal control group(NC),model group,ischemia-reperfusion group(IR),hesperidin group,SIRT1 inhibitor group and hesperidin plus SIRT1 inhibitor group.In addition to NC,the rats in the remaining groups were replicated by intraperitoneal of high-fat diet combined with injection of streptozotocin for type 2 diabetic rats.After then,the myocardial ischemia/reperfusion injury(MIRI)rat model was established by LAd for 30 minutes with 2 hours reperfusion.He staining was used to observe the pathological changes of myocardial tissue,and the levels of serum LDH,CK-MB and SOD,GSH and MDA in myocardial tissue were detected by kit methods,and the expression abundance of related proteins in 4-HNE and SIRT1/Nrf2/HO-1 signal pathway were detected by immunohistochemistry and Western blot;Results:Hesperidin could significantly inhibit cardiomyocyte necrosis and inflammatory cell infiltration,reduce LDH activity,CK-MB and MDA level,and increase SOD activity,GSH and 4-HNE level,the differences were statistically significant when compared with IR group(P<0.01).In addition,compared with the ischemia-reperfusion group,the expressions of SIRT1,Nrf2 and HO-1 proteins in hesperidin group were significantly up-regulated,the differences were statistically significant(P<0.01);Conclusion:Hesperidin inhibits oxidative stress by activating SIRT1/Nrf2/HO-1 signaling pathway,and play a protective effect of myocardial ischemia reperfusion injury in diabetic rats.

Effect and Mechanism of Dicliptera chinensis Polysaccharide on miR-141/AMPK/SIRT1 Signaling Pathway in Rats with NAFLD

[Objectives]Non-alcoholic fatty liver disease(NAFLD)rat model was established by feeding high-fat and high-sugar fodder to rats,and the protective effect of Dicliptera chinensis polysaccharide(DCP)on NAFLD rats was studied to explore its potential mechanism.[Methods]45 SD rats were randomly divided into 4 groups:normal control group,model control group and DCP treatment groups(100 and 300 mg/kg).The rats in the normal control group were fed with ordinary fodder,and the rats in other groups were fed with high-fat and high-sugar diet for 14 weeks to establish NAFLD model.From the 9^(th)week,the rats in the DCP treatment groups were given different doses of DCP by intragastric administration(5 mL/kg)for 6 weeks.After the last intragastric administration,the rats fasted for 16 h,and the serum and liver of rats were collected for detection.Hematoxylin-eosin(HE)staining was conducted to observe the histopathological changes of rat liver,and alanine aminotransferase(ALT),aspartate aminotransferase(AST),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),malondialdehyde(MDA),triglyceride(TG),total cholesterol(TC),low density lipoprotein cholesterol(LDL-C),and high density lipoprotein cholesterol(HDL-C)were detected by biochemical method.Interleukin-6(IL-6),interleukin-1β(IL-1β),tumor necrosis factor(TNF-α)and micrornA-141(micro RNA-141)were detected by reverse transcription-polymerase chain reaction(RT-PCR).The expression of SIRT1 and adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK)in rat liver was detected by western blot.[Results]Compared with the model control group,the inflammatory damage and steatodegeneration of rats in the DCP groups were relieved to varying degrees,and the number of lipid vacuoles significantly reduced.The ALT,AST,TC,TG and LDL-C content in the serum and MDA content in the liver tissue decreased to varying degrees,while the HDL-C,SOD and GSH-Px content increased.The expression of SIRT1 and AMPK increased,while the expression of miR-141,TNF-α,IL-6 and IL-1βdeclined,and the DCP 300 mg/kg treatment group had better improvement effect.[Conclusions]DCP had a certain protective effect on NAFLD rats,which may be related to the regulation of miR-141/AMPK/SIRT1 signaling pathway.

Yiqi Yangyin and Huatan Quyu granule can improve skeletal muscle energy metabolism in a type 2 diabetic rat model by promoting the AMPK/SIRT/PGC-1α signalling pathway

Objective:To investigate how Yiqi Yangyin and Huatan Quyu granule (YYHO) improves skeletal muscle insulin resistance in a type 2 diabetic rat model and to discover whether the molecular mechanism is related to the promotion of the AMPK/SIRT/PGC-1α signalling pathway.Methods:Rats were randomly divided into 4 groups:the normal group,the model group,the YYHQ granule group,and the pioglitazone group.The type 2 diabetic rat model was established by feeding a high-fat diet for 5 weeks along with a single intraperitoneal injection of 30 mg/kg streptozotocin (STZ).After modelling successfully,the appropriate drug was intragastrically administered to diabetic rats for 2 weeks,once per day.The YYHQ granule group was given a dose of 4.8 g/kg body weight per day,the pioglitazone group was given a dose of 1.35 mg/kg body weight per day.The doses for both groups were equivalent to the clinical equivalent dose based on a previous study.Other groups were gavaged with the same amount of saline water.Body weight,food intake,water intake,urine volume and grip strength were recorded weekly.The fasting blood glucose(FBG) was determined weekly using blood glucose test strips.The related glucose and lipid metabolism indexes,e.g.,fasting insulin (Fins),glycated haemoglobin (GHb),HOMA-IR,ISI,triglycerides (TG),total cholesterol (TC),high-density lipoprotein cholesterol (HDL-C),low-density lipoprotein cholesterol (LDL-C) and free fatty acid (FFA),were determined using biochemical method.The mRNA expression levels of adenosine monophosphate-activated protein kinase (AMPK),peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α),carnitine palmitoyl transterase-1 (CPT-1),Sirtuin 1 (SIRT1),and Sirtuin 3 (SIRT3) were assessed using quantitative real-time PCR (qRT-PCR).The protein expression levels of creatine kinase (CK),Ca2+ ATPase,α-Actin,AMPK,PGC-1α and CPT-1 were determined using enzyme-linked immunosorbent assay method (ELISA).Results:Body weight decreased significantly (P <.01),food intake,water intake and urine volume increased significantly (P <.01),and grip strength decreased significantly (P <.01) in the model group compared with the normal group.The levels of FBG,Fins,GHb and HOMA-IR increased significantly (P <.01),and the ISI decreased significantly (P <.01) in the model group.The levels of TG,TC,LDL-C and FFA increased significantly (P <.05 or P <.01),and the level of HDL-C decreased significantly (P <.05) in the model group.These changes were reversed after treatment with YYHQ granule or pioglitazone.Compared with the model group,the YYHQ granule and pioglitazone groups significantly improve body weight,water intake and urine volume (P <.05 or P <.01),however,both treatments had no significant effect on food intake (P >.05).The levels of FBG,Fins,GHb,HOMA-IR and ISI were improved significantly (P <.01) and the levels of TG,TC and LDL-C were improved significantly (P <.05 or P <.01),however,both treatments had no significant effect on the levels of HDL-C and FFA (P >.05).Further results indicated that YYHQ granule significantly decreased the mRNA expression of AMPK,PGC-1α,CPT-1,SIRT1 and SIRT3 in skeletal muscle (P <.01) and the pioglitazone group showed similar effects;moreover,the protein expression levels of CK,Ca2+ATPase,α-Actin,AMPK,PGC-1α and CPT-1 in skeletal muscle significantly decreased (P <.01),however,pioglitazone had no significant effect on CK and α-Actin (P >.05).Conclusion:The possible molecular mechanism of YYHQ granule improving skeletal muscle insulin resistance in a type 2 diabetic rat model may be related to the stimulation of energy metabolism in skeletal muscle via the AMPK/SIRT/PGC-1α signalling pathway.

炎症因子IFN-γ调控小鼠成肌细胞FoxO1乙酰化及活性的机制研究

目的 :在炎症信号IFN-γ作用下,研究小鼠成肌细胞(C2C12)内Fox O1的活性和乙酰化水平的改变,探讨炎症在2型糖尿病发病过程中的机制。方法:免疫共沉淀分析Ⅲ型脱乙酰化酶沉默信息调节因子1(silent information regulator 1,SIRT1)激动剂白藜芦醇对IFN-γ升高Fox O1乙酰化水平的影响。通过荧光素酶报告基因活性实验分析IFN-γ、CⅡTA对Fox O1转录活性的影响,同时用小RNA干扰内源性CⅡTA后再检测IFN-γ作用下Fox O1转录活性的改变。结果:蛋白实验显示,IFN-γ处理后Fox O1乙酰化水平明显升高,白藜芦醇降低该效应。报告基因实验显示IFN-γ抑制野生型Fox O1的转录活性,对赖氨酸突变的Fox O1作用不大。过表达CⅡTA抑制了Fox O1靶基因FHRE启动子的活性,且在同时转染Fox O1时抑制60%左右。IFN-γ抑制Fox O1的转录活性,内源性CⅡTA干扰后再给予IFN-γ,抑制作用消失。结论 :IFN-γ通过激活CⅡTA降低SIRT1酶活性,使SIRT1对Fox O1的去乙酰化作用减弱,提高了Fox O1乙酰化水平,抑制了Fox O1的转录活性。本研究为临床2型糖尿病的治疗提供了新思路。

白皮杉醇对糖尿病肾病肾小管间质纤维化、肾小管凋亡及FoxO1表达的影响

目的探究白皮杉醇(Pic)对糖尿病肾病(DN)肾小管间质纤维化、肾小管凋亡的影响及潜在机制。方法选择雄性C57BL/6小鼠40只,随机分为对照(Control)组、模型(Model)组、Pic低剂量(Low-Pic)组、Pic中剂量(Mid-Pic)组及Pic高剂量(High-Pic)组各8只。除Control组外,其他组进行高糖高脂饮食,并配合链脲佐菌素(STZ)腹腔注射诱导构建DN小鼠模型。Low-Pic、Mid-Pic及High-Pic组DN造模成功后,分别给予Pic 10、20及40 mg/kg灌胃2 w,Control组及Model组给予等量生理盐水灌胃。留取血清及肾脏组织,检测小鼠空腹血糖、血清肌酐、尿素氮及24 h尿总蛋白;采用Western印迹测定肾脏组织蛋白表达。体外培养人肾小管上皮细胞株(HK)-2,随机分为Control组、Model组、Low-Pic组、Mid-Pic组及High-Pic组。除Control组外,使用30 mmol/L D-葡萄糖对其他组处理72 h,对Low-Pic组、Mid-Pic组及High-Pic组分别给予Pic 10、20及40μmol/L处理24 h,采用Western印迹测定细胞蛋白表达。结果Model组空腹血糖、血清肌酐、尿素氮及24 h尿蛋白总量显著高于Control组,Low-Pic、Mid-Pic、High-Pic组可呈显著剂量依赖性逆转(均P<0.05)。在HK-2细胞系中,与Control组相比,Model组细胞纤维化相关蛋白E-钙黏附蛋白(cadherin)表达降低,α-SMA表达升高,促凋亡相关蛋白Cleaved Caspase-3及Bax表达升高,差异均有统计学意义(P<0.05),而Low-Pic、Mid-Pic、High-Pic组可逆转上述变化,且呈显著剂量依赖性(均P<0.05)。此外,Pic各组沉默调节蛋白(Sirt)1和磷酸化叉头框蛋白(Fox)O1蛋白表达水平均显著高于Model组,且随着Pic浓度升高,效果越明显(均P<0.05)。结论Pic可减轻DN引起的肾功能损伤,并抑制肾小管纤维化及凋亡,其发挥保护性作用可能是通过调节Sirt1/FoxO1活化实现。

Quercetin ameliorates oxidative stress-induced senescence in rat nucleus pulposus-derived mesenchymal stem cells via the miR-34a-5p/SIRT1 axis

BACKGROUND Intervertebral disc degeneration(IDD)is a main contributor to low back pain.Oxidative stress,which is highly associated with the progression of IDD,increases senescence of nucleus pulposus-derived mesenchymal stem cells(NPMSCs)and weakens the differentiation ability of NPMSCs in degenerated intervertebral discs(IVDs).Quercetin(Que)has been demonstrated to reduce oxidative stress in diverse degenerative diseases.AIM To investigate the role of Que in oxidative stress-induced NPMSC damage and to elucidate the underlying mechanism.METHODS In vitro,NPMSCs were isolated from rat tails.Senescence-associatedβ-galactosidase(SA-β-Gal)staining,cell cycle,reactive oxygen species(ROS),realtime quantitative polymerase chain reaction(RT-qPCR),immunofluorescence,and western blot analyses were used to evaluated the protective effects of Que.Meanwhile the relationship between miR-34a-5p and Sirtuins 1(SIRT1)was evaluated by dual-luciferase reporter assay.To explore whether Que modulates tert-butyl hydroperoxide(TBHP)-induced senescence of NPMSCs via the miR-34a-5p/SIRT1 pathway,we used adenovirus vectors to overexpress and downregulate the expression of miR-34a-5p and used SIRT1 siRNA to knockdown SIRT1 expression.In vivo,a puncture-induced rat IDD model was constructed,and X rays and histological analysis were used to assess whether Que could alleviate IDD in vivo.RESULTS We found that TBHP can cause NPMSCs senescence changes,such as reduced cell proliferation ability,increased SA-β-Gal activity,cell cycle arrest,the accumulation of ROS,and increased expression of senescence-related proteins.While abovementioned senescence indicators were significantly alleviated by Que treatment.Que decreased the expression levels of senescence-related proteins(p16,p21,and p53)and senescence-associated secreted phenotype(SASP),including IL-1β,IL-6,and MMP-13,and it increased the expression of SIRT1.In addition,the protective effects of Que on cell senescence were partially reversed by miR-34a-5p overexpression and SIRT1 knockdown.In vivo,X-ray,and histological analyses indicated that Que alleviated IDD in a punctureinduced rat model.CONCLUSION In summary,the present study provides evidence that Que reduces oxidative stress-induced senescence of NPMSCs via the miR-34a/SIRT1 signaling pathway,suggesting that Que may be a potential agent for the treatment of IDD.

中药复方益糖康颗粒通过AGE-RAGE轴介导SIRT1调控PI3K/Akt/FoxO1信号通路促进足细胞自噬的机制

目的:通过观察中药复方益糖康(YTK)颗粒对晚期糖基化终末产物(AGE)-晚期糖基化终产物受体(RAGE)轴介导沉默信息调节因子1(SIRT1)调控磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(Akt)/叉头框蛋白O1(FoxO1)信号通路改善糖尿病肾脏疾病(DKD)大鼠足细胞自噬的影响,探讨YTK治疗DKD的可能作用机制。方法:选取8周龄SPF级健康雄性Wistar大鼠96只,使用随机数字表法分为空白组、模型组、YTK高、中、低剂量组(40、20、10 g·kg^(-1))、西药组(氯沙坦片,20 mg·kg^(-1)),采用高脂饲料喂养联合腹腔注射链脲佐菌素建立DKD大鼠模型。造模成功后,各组按照相应比例剂量连续给药8周后取材。严格按照试剂盒所示方法检测超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)的水平;苏木素-伊红(HE)染色观察肾脏组织病理形态学变化;免疫组化法检测α-平滑肌肌动蛋白(α-SMA)、纤维连接蛋白(FN)、肌间质蛋白(Desmin)、裂孔膜蛋白(Nephrin)的平均积分吸光度值;蛋白免疫印迹法(Western blot)分析DKD大鼠肾组织中滑膜PI3K、磷酸化磷脂酰肌醇3-激酶(p-PI3K)、Akt、磷酸化蛋白激酶B(p-Akt)、RAGE、SIRT1、胱天蛋白酶-3(Caspase-3)、FoxO1的蛋白表达水平。结果:与空白组比较,模型组SOD、GSH-Px、CAT表达水平明显降低,MDA显著升高(P<0.01);大鼠呈现严重肾损现象;足细胞标志蛋白α-SMA、FN、Desmin阳性表达显著增多,Nephrin、足突蛋白质(Podocin)显著下降(P<0.01);肾组织中PI3K、p-PI3K、Akt、p-Akt、RAGE、Caspase-3蛋白表达水平显著升高,SIRT1、FoxO1蛋白表达水平显著降低(P<0.01)。与模型组比较,YTK各剂量组大鼠血清中SOD、GSH-Px、CAT水平显著升高,MDA显著下降(P<0.01);肾损程度均发生了不同程度减轻;足细胞标志蛋白α-SMA、FN、Desmin平均积分吸光度值均明显降低,Nephrin、Podocin显著升高(P<0.01);肾组织中PI3K、p-PI3K、Akt、p-Akt、RAGE、Caspase-3表达水平显著降低,SIRT1、FoxO1表达水平显著提升(P<0.01)。中药组表现出明显的量效趋势。结论:YTK可能通过AGE-RAGE轴介导SIRT1调控PI3K/Akt/FoxO1信号通路,改善足细胞自噬,从而减轻肾脏病理损害,减少蛋白尿,保护肾功能,达到延缓DKD进展的目的。且中药组具有量效趋势。

Danshensu Ameliorates Cardiac Ischaemia Reperfusion Injury through Activating Sirt1/Fox01/Rab7 Signal Pathway

Objective:To explore the specific molecular mechanisms of Danshensu(DSS)in the treatment of ischemia reperfusion injury(IRI).Methods:IRI model was established with isolated rat hearts by performing global ischaemia for 30 min,and then followed by 60 min reperfusion.Also,H9C2 cells were subjected to 4-h hypoxia followed by 3-h reoxygenation.Then 10|i mol/L DSS were added in the reperfusion/reoxygenation step to intervene IRI.Cardiac function,structural change and apoptosis were respectively tested by Langendorff System,hematoxylin and eosin(HE)and terminal-deoxynucleotidyl transferase mediated nick endabeling(TUNEL)stainings.Then lactate dehydrogenase(LDH),cardiac troponin T(cTnT),reactive oxygen species(ROS),superoxide dismutase(SOD)and glutathione peroxidase(GSH-PX)were detected by enzyme-linked immunosorbent assay(ELISA).Sirt1/FoxO1/Rab7 Signal Pathway was monitored at both protein and mRNA levels.Results:The results showed that IRI not only greatly attenuated cardiac function(LVDP and±dp/dtmax,P<0.01,P<0.05)and increased the level of the marker enzymes(cTnT,LDH,P<0.01)from the coronary effluents,but also markedly induced changes in the structure of cardiomyocytes and contributed to apoptosis,which were mediated by boosted en doge nous ROS.However,after treatment with DSS all above indexes were improved,which was related to activating Sirt1/FoxO1/Rab7 signal pathway accompanied with the enhancement of antioxidant defense system,such as SOD and GSH-PX.Conclusion:DSS is able to protect hearts from IRI,which may be attributable to inhibiting excessive ROS through Sirt1/FoxO1/Rab7 signaling.

姜黄素后处理通过SIRT1/FOXO1信号通路拮抗小鼠脑缺血再灌注损伤

目的:探究姜黄素后处理是否通过激活SIRT1/FOXO1信号通路抵抗小鼠脑缺血再灌注损伤。方法:小鼠脑缺血30 min,再灌注24 h建立脑缺血再灌注模型。手术前脑室内注射SIRT1特异性抑制剂EX527。再灌注后腹腔注射姜黄素。小鼠随机分为以下6组:假手术组;单纯姜黄素后处理组;缺血再灌注组;缺血再灌注+姜黄素后处理组;EX527预处理+缺血再灌注+姜黄素后处理组;EX527预处理+脑缺血再灌注组。再灌注24 h检测脑梗体积、Complex I活性、ROS含量以及SIRT1、Ac-FOXO1、Bax、Bcl-2、Caspase-3蛋白表达情况。结果:与手术组相比,姜黄素后处理组梗死区脑组织SIRT1的表达量及活性明显增加,脑梗体积降低,ROS含量降低而Complex I活性增高,Bcl-2的表达增高而Bax和Caspase-3的表达量降低(均P<0.05)。阻断SIRT1信号通路后上述姜黄素脑保护作用均减弱(P<0.05)。结论:我们的研究首次证实姜黄素后处理通过激活SIRT1/FOXO1信号通路,进而降低氧化应激与凋亡,最终减轻脑缺血再灌注损伤。

降脂通络软胶囊调控SIRT1/FoxO3通路对膜性肾病大鼠细胞凋亡的影响

目的:通过观察降脂通络软胶囊对膜性肾病(MN)大鼠肾组织中沉默信息调节因子2相关酶1(SIRT1)/叉头转录因子O3(FoxO3)蛋白表达及足细胞凋亡的影响,探讨其治疗MN的可能分子机制。方法:将60只雄性SD大鼠随机分为6组,每组10只,随机选取1组作为正常组,其余5组分别为模型组、盐酸贝那普利(西药)组(10 mg·kg^(-1))和降脂通络软胶囊低、中、高剂量(中药低、中、高剂量)组(25、50、100 mg·kg^(-1)),并通过尾静脉注射阳离子化牛血清白蛋白(C-BSA)的方法造模。造模成功后,各组按照相应比例剂量连续4周灌胃给药,并在第4周末留取肾组织,采用电镜、免疫荧光观察肾脏病理学变化,蛋白免疫印迹法(Western blot)检测大鼠肾脏SIRT1、FoxO3蛋白的表达情况,免疫组化(IHC)检测B细胞淋巴瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)、死亡启动子重组蛋白(Bad)、足细胞裂孔膜蛋白(Nephrin)、膜蛋白(Podocin)的蛋白表达情况。结果:与正常组比较,模型组大鼠肾组织中促凋亡因子Bax、Bad、FoxO3蛋白表达均明显增加(P<0.05),抗凋亡因子Bcl-2、SIRT1、Nephrin、Podocin蛋白表达均降低(P<0.05);与模型组比较,各治疗组肾组织中Bax、Bad、FoxO3蛋白表达明显减少(P<0.05),Bcl-2、SIRT1、Nephrin、Podocin表达明显升高(P<0.05)。结论:降脂通络软胶囊对MN的肾保护作用可能与其调控SIRT1/FoxO3通路,减少足细胞凋亡,维护足细胞结构稳定有关。

Ginsenoside Rb1 Protects Human Umbilical Vein Endothelial Cells against High Glucose-Induced Mitochondria-Related Apoptosis through Activating SIRT3 Signalling Pathway

Objective:To investigate whether ginsenoside Rb1(Rb1)can protect human umbilical vein endothelial cells(HUVECs)against high glucose-induced apoptosis and examine the underlying mechanism.Methods:HUVECs were divided into 5 groups:control group(5.5 mmol/L glucose),high glucose(HG,40 mmol/L)treatment group,Rb1(50μmol/L)treatment group,Rb1 plus HG treatment group,and Rb1 and 3-(1 H-1,2,3-triazol-4-yl)pyridine(3-TYP,16μmol/L)plus HG treatment group.Cell viability was evaluated by cell counting kit-8 assay.Mitochondrial and intracellular reactive oxygen species were detected by Mito Sox Red mitochondrial superoxide indicator and dichloro-dihydro-fluorescein diacetate assay,respectively.Annexin V/propidium iodide staining and fluorescent dye staining were used to measure the apoptosis and the mitochondrial membrane potential of HUVECs,respectively.The protein expressions of apoptosis-related proteins[Bcl-2,Bax,cleaved caspase-3 and cytochrome c(Cyt-c)],mitochondrial biogenesis-related proteins[proliferator-activated receptor gamma coactivator 1-alpha,nuclear respiratory factor-1 and mitochondrial transcription factor A],acetylation levels of forkhead box O3 a and SOD2,and sirtuin-3(SIRT3)signalling pathway were measured by immunoblotting and immunoprecipitation.Results:Rb1 ameliorated survival in cells in which apoptosis was induced by high glucose(P<0.05 or P<0.01).Upon the addition of Rb1,mitochondrial and intracellular reactive oxygen species generation and malondialdehyde levels were decreased(P<0.01),while the activities of antioxidant enzymes were increased(P<0.05 or P<0.01).Rb1 preserved the mitochondrial membrane potential and reduced the release of Cyt-c from the mitochondria into the cytosol(P<0.01).In addition,Rb1 upregulated mitochondrial biogenesis-associated proteins(P<0.01).Notably,the cytoprotective effects of Rb1 were correlated with SIRT3 signalling pathway activation(P<0.01).The effect of Rb1 against high glucose-induced mitochondria-related apoptosis was restrained by 3-TYP(P<0.05 or P<0.01).Conclusion:Rb1 could protect HUVECs from high glucose-induced apoptosis by promoting mitochondrial function and suppressing oxidative stress through the SIRT3 signalling pathway.

基于SIRT1/FoxO1通路探究小檗碱抑制卵巢颗粒细胞凋亡与自噬的调节机制

目的:通过观察小檗碱(BBR)对卵巢颗粒细胞衰老的影响,探究其保护作用及调节机制。方法:应用H_(2)O_(2)诱导建立人卵巢颗粒样肿瘤(KGN)细胞衰老模型;设置空白组、模型组、BBR高剂量(1μmol·L^(-1))组和BBR低剂量(0.5μmol·L^(-1))组,模型组与BBR组加入浓度为10μmol·L^(-1)H_(2)O_(2),孵育40 min。通过细胞增殖与活性检测(CCK-8)分析检测BBR对KGN细胞增殖的影响;通过β-半乳糖苷酶染色检测BBR对KGN细胞衰老状态的影响;应用流式细胞术检测BBR对KGN细胞凋亡和ROS含量的影响;实时荧光定量聚合酶链式反应(Real-time PCR)检测BBR对KGN细胞抗凋亡蛋白B细胞淋巴瘤-2(Bcl-2)/促凋亡蛋白Bcl-2相关X蛋白(Bax)比值、胱天蛋白酶-3(Caspase-3)、叉头框转录因子O1(FoxO1)及过氧化氢酶(CAT)mRNA表达的影响;蛋白免疫印迹法(Western blot)检测BBR对KGN细胞沉默信息调节因子1(SIRT1)、超氧化物歧化酶2(SOD2)、c-Jun氨基末端激酶(JNK)、FoxO1、自噬相关蛋白微管相关蛋白轻链3Ⅱ(LC3BⅡ)、自噬关键分子酵母Atg6(Beclin-1)及泛素结合蛋白p62蛋白表达的影响。结果:H_(2)O_(2)诱导40 min后,与空白组比较,模型组细胞增殖率显著下降(P<0.01);与模型组比较,BBR干预组细胞增殖率明显上升(P<0.05);β-半乳糖苷酶染色结果显示,与空白组比较,模型组细胞呈现明显的衰老状态(P<0.01),BBR干预组细胞衰老情况较模型组显著降低(P<0.01);流式细胞术检测显示,与空白组比较,模型组细胞凋亡率显著上升(P<0.01),BBR干预组细胞凋亡率较模型组明显降低(P<0.05);同时,与空白组比较,模型组ROS含量显著增加(P<0.01);与模型组比较,BBR干预组细胞ROS含量显著降低(P<0.01);Real-time PCR结果显示,与空白组比较,模型组KGN细胞CAT、Bcl-2/Bax mRNA表达明显降低,Caspase-3与FoxO1 mRNA表达明显增加(P<0.05);与模型组比较,BBR干预后KGN细胞CAT与Bcl-2/Bax mRNA表达明显增加(P<0.05),Caspase-3与FoxO1 mRNA表达较模型组明显降低(P<0.05)。Western blot结果显示,与空白组比较,模型组SIRT1、SOD2及p62蛋白水平显著降低(P<0.01),JNK、FoxO1、LC3BⅡ与Beclin-1蛋白水平明显升高(P<0.05);BBR干预后,SIRT1、SOD2及p62蛋白水平较模型组显著增加(P<0.01),JNK、FoxO1、LC3BⅡ与Beclin-1蛋白水平较模型组明显降低(P<0.05)。结论:BBR具有抑制卵巢颗粒细胞衰老效应,其机制与通过SIRT1/FoxO1通路介导抑制细胞凋亡与自噬有关。

葛根芩连汤对db/db糖尿病小鼠SIRT1/FoxO1自噬通路的影响

目的:探究葛根芩连汤是否通过调控沉默信息调节因子1(SIRT1)/叉头框蛋白O1(FoxO1)自噬通路减轻db/db糖尿病小鼠胰岛素抵抗。方法:选取SPF级自发性2型糖尿病动物模型db/db小鼠75只及对照db/m小鼠15只予维持饲料喂养1周后检测血糖,随机分为6组,每组15只。正常组(生理盐水0.2 g·kg^(-1))、二甲双胍组(0.2 g·kg^(-1))、葛根芩连汤高、中、低剂量组(31.9、19.1、6.9 g·kg^(-1))及模型组(生理盐水0.2 g·kg^(-1)),连续灌胃给药8周,1次/d,使用罗氏血糖仪检测空腹血糖(FBG),全自动生化分析仪检测血清中高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、甘油三酯(TG)和总胆固醇(TC)水平,酶联免疫吸附测定法(ELISA)检测血清空腹胰岛素(INS)水平,计算胰岛素抵抗指数(HOMA-IR);采用蛋白免疫印迹法(Western blot)检测肝脏组织中Beclin-1、微管相关蛋白1轻链3(LC3)及SIRT1/FoxO1自噬通路相关蛋白的表达;免疫组化检测肝脏组织中SIRT1、FoxO1、Beclin-1、LC3B蛋白的表达;透射电镜观察肝脏自噬小体形成。结果:与正常组比较,模型组FBG、FINS、HOMA-IR、TC、TG、LDL-C、HDL-C水平显著升高(P<0.01),肝脏组织SIRT1、Beclin-1、LC3蛋白表达显著升高(P<0.01),FoxO1显著升高(P<0.01),透射电镜显示模型组自噬小体最多;与模型组比较,二甲双胍组、葛根芩连汤低、中、高剂量组血清FBG、FINS、HOMA-IR、TC、TG、LDL-C、HDL-C水平明显降低(P<0.05,P<0.01),肝脏组织SIRT1、Beclin-1、LC3蛋白表达明显降低(P<0.05,P<0.01),FoxO1显著降低(P<0.01),透射电镜显示用药组自噬程度有所减轻;与二甲双胍组比较,葛根芩连汤中、高剂量组FBG、FINS、TG水平显著降低(P<0.01),肝脏组织SIRT1、Beclin-1、LC3蛋白表达明显降低(P<0.05,P<0.01),FoxO1显著降低(P<0.01),葛根芩连汤高剂量HOMA-IR、TC、LDL-C、HDL-C水平明显降低(P<0.05,P<0.01),透射电镜显示葛根芩连汤中、高剂量组自噬小体明显减少。结论:葛根芩连汤可显著改善糖脂代谢紊乱,通过激活SIRT1/FoxO1自噬通路减轻db/db小鼠胰岛素抵抗从而防治2型糖尿病。