基于PERK/Nrf2/HO-1信号通路研究瑞马唑仑对心肌缺血再灌注损伤大鼠铁死亡的影响

摘要 目的：基于蛋白激酶R样内质网激酶（PERK）/核因子E2相关因子2（Nrf2）/血红素氧合酶-1（HO-1）信号通路探究瑞马唑仑对心肌缺血再灌注损伤（MIRI）大鼠铁死亡的影响。方法：将90只SD大鼠随机分为假手术（Sham）组、MIRI组、低剂量-瑞马唑仑组（L-瑞马唑仑组,5 mg/kg）、高剂量-瑞马唑仑组（H-瑞马唑仑组,20 mg/kg）、H-瑞马唑仑+PERK抑制剂组（瑞马唑仑20 mg/kg+GSK2606414 1 mg/kg）,每组18只。采用结扎冠状动脉左前降支（LAD）0.5 h、再灌注2 h制备MIRI大鼠模型,于再灌注2 h后即刻尾静脉注射给药,再灌注24 h后进行组织取材。酶联免疫吸附（ELISA）法检测血清心肌损伤标志物[肌酸激酶同工酶（CK-MB）、心肌肌钙蛋白I（cTnI）]水平;HE染色观察心肌组织病理改变;Tunel染色检测心肌细胞凋亡;透射电镜观察心肌细胞超微结构变化;检测心肌组织中铁死亡相关标志物[铁、活性氧（ROS）、谷胱甘肽（GSH）、丙二醛（MDA）]水平;蛋白质印迹法（Western Blot）检测心肌组织中PERK/Nrf2/HO-1信号通路相关蛋白表达。结果：与Sham组相比,MIRI组心肌结构受损,纤维排列紊乱,线粒体呈现显著的铁死亡特征（膜固缩,膜密度增加,嵴减少）,血清中CK-MB、cTnI水平,心肌细胞凋亡率及心肌组织中铁、ROS、MDA水平升高（P<0.05）,心肌组织中GSH水平及p-PERK/PERK、核Nrf2/Nrf2、HO-1蛋白表达降低（P<0.05）;与MIRI组相比,L-瑞马唑仑组和H-瑞马唑仑组心肌组织上述病理改变明显减轻,血清CK-MB、cTnI水平,心肌细胞凋亡率及心肌组织中铁、ROS、MDA水平降低（P<0.05）,心肌组织中GSH水平及p-PERK/PERK、核Nrf2/Nrf2、HO-1蛋白表达升高（P<0.05）;与H-瑞马唑仑组相比,H-瑞马唑仑+PERK抑制剂组心肌组织上述病理改变加重,血清CK-MB、cTnI水平,心肌细胞凋亡率及心肌组织中铁、ROS、MDA水平升高（P<0.05）,心肌组织中GSH水平及p-PERK/PERK、核Nrf2/Nrf2、HO-1蛋白表达降低（P<0.05）。结论：瑞马唑仑可通过抑制铁死亡减轻大鼠MIRI,可能通过激活PERK/Nrf2/HO-1信号通路而实现。     

miR-19通过Keap-Nrf2/HO-1信号通路对卵巢癌细胞增殖的影响

摘要 目的：研究卵巢癌组织和细胞中miR-19的表达,探讨其异常表达对卵巢癌细胞Kelch样环氧氯丙烷相关蛋白-1（Kelch-like epichlorohydrin-associated protein1,Keap1）--核因子E2相关因子2（nuclearfactor-E2-relatedfactor2,Nrf2） /血红素氧合酶-1（heme oxygenase1,HO-1）信号通路及卵巢癌细胞增殖的影响。方法：回顾性收集2019年1月至2020年12月于我院就诊的患者经病理切片诊断为卵巢癌上皮细胞的手术标本30例,卵巢良性肿瘤标本30例,正常卵巢组织标本30例。免疫组化检测不同标本中Keap1、Nrf2、HO-1的表达,检测卵巢组织及细胞中miR-19、Keap1、Nrf2、HO-1的mRNA表达水平,及卵巢癌细胞中Keap1、Nrf2、HO-1的蛋白表达水平。在OVCAR-3细胞中沉默miR-19后,Western Blot检测细胞内Keap1、Nrf2、HO-1蛋白表达水平,收集沉默miR-19,对照组,沉默Nrf2、对照组的OVCAR-3细胞,继续培养0 h、24 h、48 h后,检测细胞增殖和凋亡。结果：Keap1蛋白在卵巢癌组织中的阳性表达显著低于良性卵巢肿瘤组织及正常卵巢组织;Nrf2和HO-1蛋白在卵巢癌组织中的阳性表达显著低于良性卵巢肿瘤组织及正常卵巢组织（P＜0.05）;沉默miR-19抑制其表达后,细胞内Keap1 mRNA、蛋白表达水平明显升高,Nrf2、HO-1 mRNA表达水平无明显变化,蛋白表达水平明显降低（P＜0.05）;沉默miR-19 组、沉默Nrf2组与转染阴性对照组相比,增殖能力明显降低,凋亡能力明显升高（P＜0.05）。结论：卵巢癌细胞中,miR-19表达水平升高,可通过调控Keap1-Nrf2/HO-1信号通路影响卵巢癌细胞的增值、凋亡能力。     

紫檀芪调节Keap-1/Nrf2/HO-1信号通路对非酒精性脂肪肝大鼠氧化应激和细胞凋亡的影响

摘要 目的：研究紫檀芪调节Kelch样ECH关联蛋白1（Keap-1）/核因子E2相关因子2（Nrf2）/血红素加氧酶-1（HO-1）信号通路对非酒精性脂肪肝（NAFLD）大鼠氧化应激和细胞凋亡的影响。方法：将60只SD大鼠随机分为对照组、模型组、紫檀芪低剂量组（30 mg/kg）、紫檀芪高剂量组（60 mg/kg）、紫檀芪（60 mg/kg）+N-（4-（2,3-二氢-1-（2''-甲基苯甲酰）-1H-吲哚-5-基）-5-甲基-2-噻唑基）-1,3-苯并二氧唑-5-乙酰胺（ML385）（30 mg/kg）组，每组12只。模型组与药物干预组大鼠以高脂饲料饲养诱导NAFLD模型，对照组大鼠以普通饲料饲养，各组连续喂养12周。以紫檀芪和ML385分组处理14 d后（对照组以等剂量生理盐水处理），检测各组大鼠脂代谢指标[三酰甘油（TG）、总胆固醇（TC）及游离脂肪酸（FFA）水平]、肝指数、肝功能指标[谷丙转氨酶（ALT）及谷草转氨酶（AST）]水平、血清白细胞介素（IL）-17、IL-6、IL-10、氧化应激指标[丙二醛（MDA）、超氧化物歧化酶（SOD）及过氧化氢酶（CAT）]水平；原位末端标记法（TUNEL）染色检测各组大鼠肝细胞凋亡率；蛋白免疫印迹法检测各组大鼠肝组织凋亡相关蛋白及Keap-1/Nrf2/HO-1通路相关蛋白表达。结果：与对照组相比，模型组大鼠血清IL-10、SOD及CAT水平、肝组织Nrf2、HO-1、Bcl-2表达水平显著降低（P＜0.05），TG、TC及FFA水平、肝指数、ALT及AST水平、血清IL-17、IL-6、MDA水平、肝细胞凋亡率、肝组织Keap-1及Bax表达水平显著升高（P＜0.05）。与模型组相比，紫檀芪低、高剂量组大鼠血清IL-10、SOD及CAT水平、肝组织Nrf2、HO-1、Bcl-2表达水平均升高（P＜0.05），TG、TC及FFA水平、肝指数、ALT及AST水平、血清IL-17、IL-6、MDA水平、肝细胞凋亡率、肝组织Keap-1、Bax表达水平均降低（P＜0.05）；与紫檀芪低剂量组相比，紫檀芪高剂量组大鼠血清IL-10、SOD及CAT水平、肝组织Nrf2、HO-1、Bcl-2表达水平升高（P＜0.05），TG、TC及FFA水平、肝指数、ALT及AST水平、血清IL-17、IL-6、MDA水平、肝细胞凋亡率、肝组织Keap-1及Bax表达水平降低（P＜0.05）；与紫檀芪高剂量组相比，紫檀芪+ML385组大鼠血清IL-10、SOD及CAT水平、肝组织Nrf2、HO-1、Bcl-2表达水平降低（P＜0.05），TG、TC及FFA水平、肝指数、ALT及AST水平、血清IL-17、IL-6、MDA水平、肝细胞凋亡率、肝组织Bax表达水平升高（P＜0.05）。结论：紫檀芪可能通过激活Keap-1/Nrf2/HO-1信号通路，改善NAFLD大鼠脂代谢水平，调节炎症反应及氧化应激，减轻肝组织脂肪变性及细胞凋亡。     

The role of Nrf2/HO-1 signal pathway in regulating aluminum-induced apoptosis of PC12 cells

BackgroundAluminum has definite neurotoxicity and can lead to apoptosis of nerve cells, but the specific mechanism remains to be further explored. The aim of this study was to investigate the role of Nrf2/HO-1 signaling pathway in neural cell apoptosis induced by aluminum exposure.MethodsIn this study, PC12 cells were used as the research object, aluminum maltol [Al(mal)₃] was used as the exposure agent, and tert-butyl hydroquinone (TBHQ), an agonist of Nrf2, was used as the intervention agent to construct an in vitro cell model. Cell viability was detected by CCK-8 method, cell morphology was observed by light microscope, cell apoptosis was measured by flow cytometry, and expression of Bax and Bcl-2 proteins and Nrf2/HO-1 signaling pathway proteins were investigated by western blotting.ResultsWith the increase of Al(mal)₃ concentration, PC12 cell viability decreased, the early apoptosis rate and total apoptosis rate increased, the ratio of Bcl-2 and Bax protein expression decreased, and Nrf2/HO-1 pathway protein expression decreased. The use of TBHQ could activate the Nrf2/HO-1 pathway and reverse the apoptosis of PC12 cells induced by aluminum exposure.ConclusionNrf2/HO-1 signaling pathway plays a neuroprotective role in the apoptosis of PC12 cells caused by Al(mal)₃, which provides a possible target for the intervention of aluminum induced neurotoxicity.     

桃叶珊瑚苷对冠心病大鼠Nrf2介导的铁死亡途径的影响

摘要 目的：探讨桃叶珊瑚苷（AU）对冠心病（CHD）大鼠的治疗作用及其对核因子红系2相关因子2（Nrf2）介导的铁死亡途径的影响。方法：将大鼠分为NC组、CHD组、L-AU组、M-AU组、H-AU组和ML385组,每组12只大鼠。NC组为正常饲料喂养的对照大鼠,其他组均为高脂饮食联合腹腔注射垂体后叶素诱导的CHD模型大鼠。NC组和CHD组大鼠灌胃0.3%羧甲基纤维素钠（CMC）,L-AU组、M-AU组和H-AU组大鼠灌胃20、40和80 mg/kg/d的桃叶珊瑚苷,ML385组大鼠灌胃80 mg/kg/d的桃叶珊瑚苷并腹腔注射30 mg/kg/d Nrf2抑制剂ML385,共给药4周。分别检测各组大鼠的心功能指标[射血分数（EF）和短轴缩短率（FS）]、血清指标[肌酸激酶同工酶MB（CK-MB）、乳酸脱氢酶（LDH）、总胆固醇（TC）、甘油三酯（TG）、低密度脂蛋白胆固醇（LDL-C）、高密度脂蛋白胆固醇(HDL-C）和游离脂肪酸（FFA）]、心肌组织氧化应激指标[还原型谷胱甘肽（GSH）和丙二醛（MDA）]和心肌组织Fe²⁺含量。通过苏木素伊红（HE）染色观察大鼠心肌形态。通过Western blot检测大鼠心肌组织中Nrf2、Kelch样ECH相关蛋白1（Keap1）、血红素加氧酶-1（HO-1）、NADPH：醌氧化还原酶-1（NQO-1）、谷胱甘肽过氧化物酶4（GPX4）、铁蛋白重链1（FTH1）和膜铁转运蛋白1（FPN1）的蛋白水平。结果：与NC组比较,CHD组大鼠的EF和FS水平降低,CK-MB和LDH水平升高,心肌出现明显损伤;TC、TG、LDL-C、FFA和MDA水平升高,HDL-C和GSH水平降低;Nrf2、HO-1、NQO-1、GPX4、FTH1和FPN1蛋白水平降低,Keap1蛋白水平升高,Fe²⁺含量升高（P<0.05）。与CHD组比较,L-AU组、M-AU组和H-AU组大鼠的EF和FS升高,CK-MB和LDH水平降低,心肌形态明显改善;TC、TG、LDL-C、FFA和MDA水平降低,HDL-C和GSH水平升高;Nrf2、HO-1、NQO-1、GPX4、FTH1和FPN1蛋白水平升高,Keap1蛋白水平降低,Fe²⁺含量降低（P<0.05）。与H-AU组比较,ML385组大鼠的EF和FS降低,CK-MB和LDH水平升高,心肌损伤加重,TC、TG、LDL-C、FFA和MDA水平升高,HDL-C和GSH水平降低;Nrf2、HO-1、NQO-1、GPX4、FTH1和FPN1蛋白水平降低,Keap1蛋白水平升高,Fe²⁺含量升高（P<0.05）。结论：桃叶珊瑚苷表现出了良好的抗冠心病作用,其机制与抑制Nrf2介导的铁死亡途径有关。     

Caspase 3/GSDME-dependent pyroptosis contributes to chemotherapy drug-induced nephrotoxicity

Chemotherapy drug-induced nephrotoxicity limits clinical applications for treating cancers. Pyroptosis, a newly discovered programmed cell death, was recently reported to be associated with kidney diseases. However, the role of pyroptosis in chemotherapeutic drug-induced nephrotoxicity has not been fully clarified. Herein, we demonstrate that the chemotherapeutic drug cisplatin or doxorubicin, induces the cleavage of gasdermin E (GSDME) in cultured human renal tubular epithelial cells, in a time- and concentration-dependent manner. Morphologically, cisplatin- or doxorubicin-treated renal tubular epithelial cells exhibit large bubbles emerging from the cell membrane. Furthermore, activation of caspase 3, not caspase 9, is associated with GSDME cleavage in cisplatin- or doxorubicin-treated renal tubular epithelial cells. Meanwhile, silencing GSDME alleviates cisplatin- or doxorubicin-induced HK-2 cell pyroptosis by increasing cell viability and decreasing LDH release. In addition, treatment with Ac-DMLD-CMK, a polypeptide targeting mouse caspase 3-Gsdme signaling, inhibits caspase 3 and Gsdme activation, alleviates the deterioration of kidney function, attenuates renal tubular epithelial cell injury, and reduces inflammatory cytokine secretion in vivo. Specifically, GSDME cleavage depends on ERK and JNK signaling. NAC, a reactive oxygen species (ROS) inhibitor, reduces GSDME cleavage through JNK signaling in human renal tubular epithelial cells. Thus, we speculate that renal tubular epithelial cell pyroptosis induced by chemotherapy drugs is mediated by ROS-JNK-caspase 3-GSDME signaling, implying that therapies targeting GSDME may prove efficacious in overcoming chemotherapeutic drug-induced nephrotoxicity.Subject terms: Apoptosis, Acute kidney injury     

牛樟芝提取物调控Nrf2/HO-1通路对酒精性肝损伤的保护作用

研究不同剂量（100、200和400mg/kg）的牛樟芝水提物（WE）、醇提后水提取物（WEE）和醇提物（EE）对酒精诱导的ICR小鼠急性肝损伤的保护作用和对Nrf2/HO-1抗氧化信号通路的影响。研究结果表明：与模型组比较,400mg/kg的WE和WEE均能显著抑制血清ALT和AST水平的升高,200mg/kg的WE和WEE分别显著降低血清ALT和AST含量。各剂量的WE、WEE和EE均能显著降低肝脏MDA含量,200和400mg/kg的WE和不同剂量的WEE均可明显提高肝脏的SOD和CAT活力。H&E染色结果表明WE、WEE和EE对酒精诱导的肝损伤均有一定的改善作用,EE处理组的效果相对较差。免疫组化染色结果表明各剂量的WE、WEE和EE均能促进Nrf2的核转位,诱导HO-1的表达,提高肝脏的抗氧化能力,对酒精诱导的急性肝损伤具有明显的保护作用。提示牛樟芝能通过调节Nrf2/HO-1抗氧化信号通路发挥解酒保肝功效。     

β-Caryophyllene Attenuates Focal Cerebral Ischemia-Reperfusion Injury by Nrf2/HO-1 Pathway in Rats

This study aimed to identify the effect of β-caryophyllene (BCP) pretreatment and elucidate the Nrf2/HO-1 signaling mechanism after focal cerebral ischemia-reperfusion (I-R) injury in rats. Adult male Sprague–Dawley rats were randomly assigned to the sham-operated group, I-R group and BCP pretreated I-R group. At 24 h after reperfusion, neurological deficits and infarct volume were evaluated. Pathological changes of neuron in hippocampuses were observed by Nissil staining and transmission electron microscopy (TEM). Oxidative stress was assessed by malondialdehyde (MDA) level, lipid peroxidation (LPO), nitric oxide (NO), superoxide dismutase (SOD) and Catalase (CAT) activity. The expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were analysed by Western blotting and real-time quantitative polymerase chain reaction (Q-PCR). The protein expression of Bcl-2 and Bax was determined by immunohistochemistry. Apoptotic cells were detected using TUNEL staining. In I-R group, neurological deficit scores, cerebral infarct volume, MDA levels, LPO content, NO level, expression of Bax and TUNEL-positive cells were found to be increased at 24 h after I-R injury, while SOD activity, CAT activity and expression of Bcl-2 were decreased. However, results in the BCP pretreatment groups were reversed. And the protein and mRNA expressions of Nrf2 and HO-1 were significantly up-regulated in the BCP pretreated I-R group. Results of Nissil staining and TEM scan manifested that BCP remarkablely improved neuronal injury after I-R in rats. All the above suggested that BCP pretreatment played a neuroprotective role in cerebral I-R injury, which might be exerted by upregulating the expression of Nrf2 and HO-1 to ameliorate oxidative damage and neuronal apoptosis.     

高糖背景下白蛋白抑制肾小管上皮细胞的自噬表达

目的:探讨高糖背景下白蛋白造成肾小管间质损伤的作用及其机制。方法:体外培养大鼠近端肾小管上皮细胞系NRK-52E细胞,观察高糖培养环境下细胞自噬表达的改变;同时观察低浓度牛血清白蛋白(BSA)单独刺激,对肾小管上皮细胞自噬蛋白表达的影响以及细胞凋亡蛋白的表达改变;接着在高糖培养环境下加入低浓度的白蛋白刺激,观察肾小管上皮细胞的损伤效应及自噬表达情况。结果:高糖培养条件下肾小管上皮细胞自噬蛋白Beclin-1表达增加(P0.05),低浓度白蛋白也诱导肾小管上皮细胞自噬蛋白Beclin-1、Atg12表达增加(P0.05),以及细胞凋亡蛋白cleaved caspase3的轻度增加,乳酸脱氢酶活性增加(P0.05);但高糖培养下,少量白蛋白却抑制了肾小管上皮细胞自噬蛋白Beclin-1、Atg12的表达,并且显著增加了肾小管上皮细胞的凋亡蛋白cleaved caspase3的表达(P0.05)。结论:自噬是细胞自身的一种保护机制。在高糖背景下,白蛋白通过影响自噬的自身调节机制,促进了肾小管间质的损害作用。     

Hydrogen‐rich water alleviates cyclosporine A‐induced nephrotoxicity via the Keap1/Nrf2 signaling pathway

Oxidative stress induced by long‐term cyclosporine A (CsA) administration is a major cause of chronic nephrotoxicity, which is characterized by tubular atrophy, tubular cell apoptosis, and interstitial fibrosis in the progression of organ transplantation. Although hydrogen‐rich water (HRW) has been used to prevent various oxidative stress‐related diseases, its underlying mechanisms remain unclear. This study investigated the effects of HRW on CsA‐induced nephrotoxicity and its potential mechanisms. After administration of CsA (25 mg/kg/day), rats were treated with or without HRW (12 mL/kg) for 4 weeks. Renal function and vascular activity were investigated. Histological changes in kidney tissues were analyzed using Masson's trichrome and terminal deoxynucleotidyl transferase dUTP nick‐end labeling stains. Oxidative stress markers and the activation of the Kelch‐like ECH‐associated protein 1 (Keap1)/nuclear factor erythroid 2‐related factor 2 (Nrf2) signaling pathway were also measured. We found that CsA increased the levels of reactive oxygen species (ROS) and malonaldehyde (MDA), but it reduced glutathione (GSH) and superoxide dismutase (SOD) levels. Such alterations induced vascular dysfunction, tubular atrophy, interstitial fibrosis, and tubular apoptosis. This was evident secondary to an increase in urinary protein, serum creatinine, and blood urea nitrogen, ultimately leading to renal dysfunction. Conversely, HRW decreased levels of ROS and MDA while increasing the activity of GSH and SOD. This was accompanied by an improvement in vascular and renal function. Moreover, HRW significantly decreased the level of Keap1 and increased the expression of Nrf2, NADPH dehydrogenase quinone 1, and heme oxygenase 1. In conclusion, HRW restored the balance of redox status, suppressed oxidative stress damage, and improved kidney function induced by CsA via activation of the Keap1/Nrf2 signaling pathway.     

银杏叶提取物对对乙酰氨基酚诱导的小鼠急性肝损伤的保护作用

目的：探究银杏叶提取物（GBE）对对乙酰氨基酚（APAP）诱导的小鼠急性肝损伤的保护作用及其机制。方法：30只小鼠随机分为对照组、模型组、GBE低、中、高剂量组（50,100,and 200 mg·kg^-1）,每组6只。除对照组外,剩余小鼠腹腔注射APAP （300 mg/kg）一次,随后GBE低、中、高剂量组按照相应剂量灌胃给药,治疗2 d后取材。观察各组肝脏大体情况和肝组织的病理组织学变化;取血测定各组小鼠血清中ALT、AST的活性和TNF-α、IL-6的水平;取肝检测各组肝组织中SOD、MPO的活性和GSH、MDA的含量;通过Western blot检测各组肝组织中Nrf2、HO-1蛋白的表达量。结果：与对照组相比,模型组肝脏明显肿大,病理表现差,血清中ALT、AST、TNF-α、IL-6的水平显著升高（P<0.01）,肝组织中GSH的含量和SOD的活性显著降低（P<0.01）,MDA的含量和MPO的活性显著升高（P<0.01）,Nrf2、HO-1蛋白表达明显下调（P<0.01）。与模型组相比,GBE组肝脏肿大减轻,病理表现有所改善,血清中ALT、AST、TNF-α、IL-6的水平显著降低（P<0.01）,肝组织中GSH的含量和SOD的活性显著提高（P<0.01）,MDA的含量和MPO的活性显著降低（P<0.01）,Nrf2、HO-1蛋白表达上调（P<0.05）,其中高剂量GBE组治疗效果最明显。结论：GBE可对APAP诱导的小鼠急性肝损伤具有保护作用,其作用机制可能是通过Nrf2/HO-1抗氧化途径发挥作用。     

Dynorphin activation of kappa opioid receptor protects against epilepsy and seizure-induced brain injury via PI3K/Akt/Nrf2/HO-1 pathway

Dynorphins act as endogenous anticonvulsants via activation of kappa opioid receptor (KOR). However, the mechanism underlying the anticonvulsant role remains elusive. This study aims to investigate whether the potential protection of KOR activation by dynorphin against epilepsy was associated with the regulation of PI3K/Akt/Nrf2/HO-1 pathway. Here, a pilocarpine-induced rat model of epilepsy and Mg²⁺-free-induced epileptiform hippocampal neurons were established. Decreased prodynorphin (PDYN) expression, suppressed PI3K/Akt pathway, and activated Nrf2/HO-1 pathway were observed in rat epileptiform hippocampal tissues and in vitro neurons. Furthermore, dynorphin activation of KOR alleviated in vitro seizure-like neuron injury via activation of PI3K/Akt/Nrf2/HO-1 pathway. Further in vivo investigation revealed that PDYN overexpression by intra-hippocampus injection of PDYN-overexpressing lentiviruses decreased hippocampal neuronal apoptosis and serum levels of inflammatory cytokines and malondialdehyde (MDA) content, and increased serum superoxide dismutase (SOD) level, in pilocarpine-induced epileptic rats. The protection of PDYN in vivo was associated with the activation of PI3K/Akt/Nrf2/HO-1 pathway. In conclusion, dynorphin activation of KOR protects against epilepsy and seizure-induced brain injury, which is associated with activation of the PI3K/Akt/Nrf2/HO-1 pathway.     

虎杖苷对老年小鼠术后认知功能障碍及海马氧化应激和神经炎症的影响

摘要 目的：探讨虎杖苷对老年小鼠术后认知功能障碍及海马氧化应激和神经炎症的影响。方法：C57BL/6J雄性老年小鼠,18月龄,体重24~28 g,随机分为4组：假手术组（Sham组）、术后认知功能障碍组（POCD组）、低剂量虎杖苷组（PD1组）、高剂量虎杖苷组（PD2组）。Sham组老年小鼠仅接受水合氯醛麻醉,不行外科手术;POCD组老年小鼠接受腹部手术以制备POCD老年动物模型;PD1组小鼠制备POCD模型,并于术后即刻、24 h和48 h分别腹腔注射低剂量虎杖苷25 mg/kg;PD2组小鼠制备POCD模型,并于术后即刻、24 h和48 h分别腹腔注射高剂量虎杖苷50 mg/kg。使用Morris水迷宫行为学实验评估老年小鼠术后认知功能,使用Western blot法检测术后小鼠海马Nrf2、HO-1、HMGB1、Iba-1蛋白水平,检测海马活性氧（ROS）、丙二醛（MDA）、超氧化物歧化酶（SOD）含量以反映术后海马氧化应激水平。结果：（1）与Sham组比较,POCD组老年小鼠术后逃离潜伏期显著增加（P<0.05）,穿越平台次数和目标象限停留时间下降（P<0.05）,海马Nrf2和HO-1蛋白表达水平明显降低（P<0.05）,氧化应激产物ROS和MDA含量增加（P<0.05）,抗氧化酶SOD活性降低（P<0.05）,Iba-1和HMGB1蛋白表达水平增加（P<0.05）;（2）与POCD组比较,PD1组和PD2组小鼠术后逃离潜伏期缩短（P<0.05）,穿越平台次数和目标象限停留时间增多（P<0.05）,海马Nrf2和HO-1蛋白表达水平升高（P<0.05）,ROS和MDA含量减少（P<0.05）,SOD活性增加（P<0.05）,Iba-1和HMGB1蛋白表达减少（P<0.05）。结论：虎杖苷可减轻老年小鼠术后认知功能损伤,缓解术后海马氧化应激和神经炎症,其机制可能与促进Nrf2/HO-1信号通路有关。     

Penehyclidine Hydrochloride Pretreatment Ameliorates Rhabdomyolysis-Induced AKI by Activating the Nrf2/HO-1 Pathway and Allevi-ating Endoplasmic Reticulum Stress in Rats

Acute kidney injury (AKI) is one of the most severe complications of rhabdomyolysis (RM). The underlying mechanisms and potential preventions need to be investigated. Penehyclidine hydrochloride (PHC) was reported to ameliorate renal ischemia-reperfusion injury, but the effect of PHC on RM-reduced AKI is unknown. In this study, we established a rat model of RM-induced AKI using an intramuscular glycerol injection in the hind limbs. Rats were pretreated with PHC before the glycerol injection, and the heme oxygenase-1 (HO-1) inhibitor ZnPP was introduced to evaluate the effect of HO-1 on RM-induced AKI. PHC pretreatment ameliorated the pathological renal injury and renal dysfunction, and decreased the renal apoptosis rate in RM-induced AKI. PHC significantly up-regulated HO-1 expression, increased HO-1 enzymatic activity and decreased the accumulation of myoglobin in renal tissues. This effect was partly inhibited by ZnPP. PHC pretreatment also effectively up-regulated nuclear factor erythroid 2-related factor 2 (Nrf2) and down-regulated glucose regulated protein 78 (GRP78) and caspase-12 at both the gene and protein levels. These results suggest that the protective effects of PHC pretreatment on RM-induced AKI occur at least in part through activating the Nrf2/HO-1 pathway and alleviating endoplasmic reticulum stress (ERS) in rat renal tissues.     

Beneficial effects of quercetin on vincristine-induced liver injury in rats: Modulating the levels of Nrf2/HO-1, NF-kB/STAT3, and SIRT1/PGC-1α

Our experimental objective was to investigate the hepatotoxic effect of vincristine (VCR) administration in rats and determined whether combined therapy with Quercetin (Quer) ensured protection. Five groups with seven rats each were used for this purpose, and experimental groups were formulated as follows: Control group; Quer group; VCR group; VCR plus Quer 25 group; VCR plus Quer 50 group. The results showed that VCR significantly increased the activity of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) enzymes. Besides, VCR caused considerable increases in the malondialdehyde (MDA) contents, along with significant decreases in reduced glutathione levels, superoxide dismutase, catalase, and glutathione peroxidase enzyme activities in the rat livers. Quer treatment in VCR toxicity markedly decreased the activity of ALT, AST, ALP enzymes, and MDA contents and enhanced the activities of antioxidant enzymes. The results also showed that VCR significantly increased the levels of NF-kB, STAT3, and the expression of caspase 3, Bax, and MAP LC3 and decreased the expression of Bcl2 and levels of Nrf2, HO-1, SIRT1, and PGC-1α. Compared to the VCR group, Quer treatment exhibited significantly lower levels of NF-kB, STAT3, and the expression of caspase 3, Bax, and MAP LC3, and higher levels of Nrf2, HO-1, SIRT1, and PGC-1α. In conclusion, our study demonstrated that Quer could alleviate the harmful effects of VCR via activation of NRf2/HO-1 and SIRT1/PGC-1α pathways, and via attenuation of oxidative stress, apoptosis, autophagy, and NF-kB/STAT3 pathways.     

Electroacupuncture Ameliorates Acute Renal Injury in Lipopolysaccharide-Stimulated Rabbits via Induction of HO-1 through the PI3K/Akt/Nrf2 Pathways

Electroacupuncture at select acupoints have been verified to protect against organ dysfunctions during endotoxic shock. And, heme oxygenase (HO)-1 as a phase II enzyme and antioxidant contributed to the protection of kidney in septic shock rats. The phosphatidylinositol 3-kinase (PI3K)-Akt pathway mediated the activation of NF-E2 related factor-2 (Nrf2), which was involved in HO-1 induction. To understand the efficacy of electroacupuncture stimulation in ameliorating acute kidney injury (AKI) through the PI3K/Akt/Nrf2 pathway and subsequent HO-1 upregulation, a dose of LPS 5mg/kg was administered intravenously to replicate the rabbit model of AKI induced by endotoxic shock. Electroacupuncture pretreatment was handled bilaterally at Zusanli and Neiguan acupoints for five consecutive days while sham electroacupuncture at non-acupoints as control. Results displayed that electroacupuncture stimulation significantly alleviated the morphologic renal damage, attenuated renal tubular apoptosis, suppressed the elevated biochemical indicators of AKI caused by LPS, enhanced the expressions of phospho-Akt, HO-1protein, Nrf2 total and nucleoprotein, and highlighted the proportions of Nrf2 nucleoprotein as a parallel. Furthermore, partial protective effects of elecroacupuncture were counteracted by preconditioning with wortmannin (the selective PI3K inhibitor), indicating a direct involvement of PI3K/Akt pathway. Inconsistently, wortmannin pretreatment made little difference to the expressions of HO-1, Nrf2 nucleoprotein and total protein, which indicated that PI3K/Akt may be not the only pathway responsible for electroacupuncture-afforded protection against LPS-induced AKI. These findings provide new insights into the potential future clinical applications of electroacupuncture for AKI induced by endotoxic shock instead of traditional remedies.