N-乙酰半胱氨酸通过AMPK/SIRT1途径抑制缺氧诱导的大鼠脑血管内皮细胞损伤

目的研究N-乙酰半胱氨酸(NAC)对缺氧诱导脑血管内皮细胞损伤的调节作用及分子机制。方法选择SD大鼠分离培养脑血管内皮细胞,分为常氧组、缺氧组、0. 5 NAC组(缺氧+0. 5 mol/L NAC)、1. 0 NAC组(缺氧+1. 0 mol/L NAC)、NAC+8-bAMP组(缺氧+1. 0 mol/L NAC+1. 0 mol/L 8-bAMP)。采用MTS法检测细胞增殖活力,采用TUNEL染色检测凋亡率,采用试剂盒检测氧化应激指标,采用Western blot检测凋亡基因、AMPK/SIRT1通路分子的表达量。结果缺氧组细胞OD490值、T-AOC含量及B淋巴细胞瘤2(Bcl-2)、p-AMP活化蛋白激酶(pAMPK)、去乙酰化酶Sirtuin1(SIRT1)表达量均明显低于常氧组;缺氧组细胞凋亡率、细胞中活性氧(ROS)、丙二醛(MDA)、8-羟基脱氧鸟苷(8-OHDG)含量及bcl-2相关X蛋白(bax)、细胞色素C(Cyt-C)、含半胱氨酸的天冬氨酸蛋白水解酶3(Caspase-3)的表达量均明显高于常氧组。0. 5 NAC组、1. 0 NAC组细胞OD490值、T-AOC量及Bcl-2、pAMPK、SIRT1表达量均明显高于缺氧组; 0. 5 NAC组、1. 0 NAC组细胞凋亡率、ROS、MDA、8-OHDG含量及Caspase-3、Cyt-C、Bax的表达量均明显低于缺氧组。NAC+8-bAMP组细胞OD490值、T-AOC及Bcl-2、p-AMPK、SIRT1表达量均明显低于1. 0 NAC组; NAC+8-bAMP组凋亡率、ROS、MDA、8-OHDG含量及Caspase-3、Cyt-C、Bax的表达量均明显高于1. 0 NAC组。结论 NAC能够通过激活AMPK/SIRT1通路来减轻氧化应激及线粒体凋亡介导的脑血管内皮细胞损伤。     

Diabetes,Metformin, and Lung Cancer: Retrospective Study of the Korean NHIS-HEALS Database

BackgroundMetformin is the first option in managing type 2 diabetes mellitus (DM) and has pleotropic effects. We studied the incidence of lung cancer in patients who received metformin therapy.Patients and MethodsThis study was retrospectively designed and based on the Korean National Health Insurance Service–National Health Screening Cohort to determine whether metformin reduces lung cancer risk in the diabetic population. At baseline, all participants were 40 to 69 years old and were categorized into 3 groups: metformin nonrecipients with DM, metformin recipients with DM, and the nondiabetic group.ResultsA total of 336,168 individuals were included in the final analysis (314,291 nondiabetic individuals, 8806 metformin recipients, and 13,071 metformin nonrecipients). The study median follow-up period was 12.86 years. The estimated cumulative lung cancer incidence of metformin nonrecipients, metformin recipients, and the nondiabetic group was 1.80%, 1.97%, and 1.24% in men and 1.87%, 0.61%, and 0.41% in women, respectively (P < .05). Compared to metformin nonrecipients, the hazard ratios (95% confidence intervals) for lung cancer incidence of metformin recipients and the nondiabetic group were 1.287 (0.979-1.691) and 0.835 (0.684-1.019) in men and 0.664 (0.374-1.177) and 0.553 (0.359-0.890) in women, respectively. The hazard ratios (95% confidence intervals) were statistically significant in male ever smokers (0.784 [0.627-0.979]) and female nonsmokers (0.498 [0.320-0.774]) after stratification according to smoking status.ConclusionMetformin therapy did not reduce lung cancer incidence in the diabetic population. However, individuals without DM were at a lower risk of lung cancer, especially in male ever smokers and female nonsmokers.     

负荷渐增式训练对老年小鼠骨骼肌卫星细胞AMPK磷酸化的影响

目的 探讨负荷渐增式训练对老年小鼠骨骼肌卫星细胞腺苷酸活化蛋白激酶（AMP-activated protein kinase，AMPK）磷酸化的影响。方法 实验小鼠分为 3 组：青年对照组（YC组，n=12）、老年对照组（OC组，n=12）与老年运动组（OT组，n=12）。OT组进行负荷渐增式训练，流式细胞分选技术分离CD45-/CD31-/Sca1-/VCAM(CD106)+细胞群体，分选细胞通过desmin、Myod肌原性染色以及成肌分化诱导培养进行肌卫星细胞鉴定，免疫组化结合Western blotting方法检测肌卫星细胞p-AMPK水平。结果 YC组骨骼肌卫星细胞AMPK及p-AMPK表达水平显著高于OC组（P<0.05）；OT组与OC组AMPK表达无明显变化（Ｐ>0.05），而OT组p-AMPK表达水平显著高于OC组（P<0.05）。结论 负荷渐增式训练可促进老年小鼠骨骼肌卫星细胞AMPK磷酸化，改善老年小鼠骨骼肌能量代谢。     

DW14006 as a direct AMPKα1 activator improves pathology of AD model mice by regulating microglial phagocytosis and neuroinflammation

Alzheimer’s disease (AD) is a progressively neurodegenerative disease with typical hallmarks of amyloid β (Aβ) plaque accumulation, neurofibrillary tangle (NFT) formation and neuronal death extension. In AD brain, activated microglia phagocytose Aβ and neuronal debris, but also aggravate inflammation stress by releasing inflammatory factors and cytotoxins. Improving microglia on Aβ catabolism and neuroinflammatory intervention is thus believed to be a promising therapeutic strategy for AD. AMP-activated protein kinase (AMPK) is highly expressed in microglia with AMPKα1 being tightly implicated in neuroinflammatory events. Since indirect AMPKα1 activators may cause side effects with undesired intracellular AMP/ATP ratio, we focused on direct AMPKα1 activator study by exploring its potential function in ameliorating AD-like pathology of AD model mice. Here, we reported that direct AMPKα1 activator DW14006 (2-(3-(7-chloro-6-(2′-hydroxy-[1,1′-biphenyl]-4-yl)-2-oxo-1,2-dihydroquinolin-3-yl)phenyl)acetic acid) effectively improved learning and memory impairments of APP/PS1 mice, and the underlying mechanisms have been intensively investigated. DW14006 reduced amyloid plaque deposition by promoting microglial o-Aβ₄₂ phagocytosis and ameliorated innate immune response by polarizing microglia to an anti-inflammatory phenotype. It selectively enhanced microglial phagocytosis of o-Aβ₄₂ by upgrading scavenger receptor CD36 through AMPKα1/PPARγ/CD36 signaling and suppressed inflammation by AMPKα1/IκB/NFκB signaling. Together, our work has detailed the crosstalk between AMPKα1 and microglia in AD model mice, and highlighted the potential of DW14006 in the treatment of AD.     

Artesunate alleviates intracerebral haemorrhage secondary injury by inducing ferroptosis in M1-polarized microglia and suppressing inflammation through AMPK/mTORC1/GPX4 pathway

Intracerebral haemorrhage (ICH) is a catastrophic subtype of stroke with severe morbidity and mortality. However, little progress has been made in the subsequent secondary injury. Artesunate, a water-soluble semi-synthetic derivative of artemisinin, exhibits remarkable pharmacological effects on anti-neuroinflammation. However, the effects of artesunate on ICH remain unknown. In the present study, haemoglobin (Hb) treatment in BV2 cell and collagenase type IV intracerebroventricular injection in Sprague–Dawley rats were used to establish in vitro and in vivo ICH models, respectively. For in vivo, the neurological scores, haematoma volume, brain oedema, inflammatory factors and iron deposition were evaluated. Besides, lipopolysaccharide (LPS) was used in in vitro to polarize BV2 cell to M1 phenotype. Cell viability, cellular reactive oxygen species (ROS), Fe²⁺ concentration, and lipid peroxidation levels, ferroptosis-associated proteins and mRNA, morphological of mitochondria were measured in vitro. Additionally, the AMP-activated protein kinase (AMPK)/mammalian/mechanistic target of rapamycin (mTOR) pathway were measured by western blot and immunofluorescence staining. The present in vivo results indicated that artesunate significantly ameliorated neurological deficits, haematoma volume and brain oedema in ICH rats. Besides, artesunate suppressed the M1-microglia relative inflammatory factors and up-regulated iron deposition. For in vitro, artesunate significantly selectively decreased the viability of LPS-stimulated BV2 cell. Furthermore, ROS and lipid peroxidation levels were up-regulated. And the glutathione peroxidase 4 (GPX4) were silenced via the AMPK/mTORC1 axis. Our finding supports that artesunate ameliorates the ICH secondary injury both in vitro and in vivo by inducing ferroptosis in microglia and further inhibiting inflammation mainly through the AMPK/mTORC1/GPX4 pathway. This finding may provide a novel target for ICH treatment.     

左、右归丸通过调节AMPK/mTOR通路抑制大鼠股骨成脂化的实验研究

目的基于AMPK/m TOR信号通路初步探讨左、右归丸对绝经后骨质疏松(postmenopausal osteoporsis,PMOP)大鼠成脂分化的调节机制。方法将60只雌性SD大鼠随机分为空白组(KB)、假手术组(SHAM)、模型组(OVX)、左归丸组(ZGW)、右归丸组(YGW)、补佳乐组(BJL)。除KB、SHAM组外,其余大鼠均摘除双侧卵巢,SHAM组大鼠摘除双侧卵巢周围等量脂肪,灌胃12周。应用数字化全身骨密度仪检测大鼠右侧股骨骨密度(bone mineral density,BMD),应用实时荧光定量PCR法检测大鼠右侧股骨PPARγ、AMPK、m TORC1 mRNA的表达,采用Western blot法检测大鼠右侧股骨PPARγ、C/EBPα、C/EBPβ蛋白的表达以及AMPKα、m TOR蛋白磷酸化水平。结果左、右归丸能明显升高PMOP大鼠右侧股骨BMD(P0.01),降低大鼠股骨成脂相关mRNA与蛋白的表达(P0.01或P0.05),降低AMPK mRNA的表达与蛋白磷酸化水平(P0.01),升高m TORC1 mRNA的表达与蛋白磷酸化水平(P0.01或P0.05);与ZGW组相比,YGW组PMOP大鼠右侧股骨BMD没有明显差异(P0.05),股骨成脂分化相关mRNA与蛋白的表达明显升高(P0.01),且AMPK mRNA的表达明显升高(P0.01),m TORC1 mRNA的表达与蛋白磷酸化水平降低(P0.01或P0.05)。结论左、右归丸通过AMPK/m TOR通路改善了PMOP大鼠股骨成脂分化过度,其作用机制可能与调节AMPK、m TOR mRNA的表达与蛋白磷酸化水平有关。     

二甲双胍联合紫杉醇对人乳腺癌细胞凋亡及AMPK信号通路的影响

目的:探索二甲双胍联合紫杉醇对乳腺癌MCF-7细胞活力和凋亡的影响及其可能的机制。方法:采用不同浓度(2、5、10、20、40和80 mmol/L)二甲双胍作用于体外培养的MCF-7细胞,MTT法检测细胞的活力。采用2 mmol/L二甲双胍和2. 4 mg/L紫杉醇单独或联合处理细胞,并加入一磷酸腺苷活化的蛋白激酶(AMPK)信号转导通路抑制剂compound C。实验分为对照组、二甲双胍组、紫杉醇组、联合组和联合+compound C组;流式细胞术检测细胞的凋亡率,采用RT-qPCR和Western blot法检测Bax、Bcl-2和caspase-3的mRNA和蛋白表达量,Western blot检测AMPK和P21蛋白的表达量。结果:不同浓度二甲双胍(2、5、10、20、40和80 mmol/L)显著抑制乳腺癌细胞的活力(P 0. 05),且具有一定浓度依赖性。与对照组相比,2 mmol/L二甲双胍和2. 4 mg/L紫杉醇单独或联合均可显著抑制细胞活力并诱导其凋亡(P 0. 05),显著下调Bcl-2水平(P 0. 05),上调Bax和caspase-3水平(P 0. 05),促进AMPK和P21蛋白表达。联合使用的效果优于单独使用。加入AMPK抑制剂可削弱此作用。结论:二甲双胍联合紫杉醇可抑制乳腺癌MCF-7细胞活力,诱导其凋亡。此作用与激活AMPK信号转导通路并调节细胞凋亡信号通路有关。     

Exercising with blocked muscle glycogenolysis: Adaptation in the McArdle mouse

Background

McArdle disease (glycogen storage disease type V) is an inborn error of skeletal muscle metabolism, which affects glycogen phosphorylase (myophosphorylase) activity leading to an inability to break down glycogen. Patients with McArdle disease are exercise intolerant, as muscle glycogen-derived glucose is unavailable during exercise. Metabolic adaptation to blocked muscle glycogenolysis occurs at rest in the McArdle mouse model, but only in highly glycolytic muscle. However, it is unknown what compensatory metabolic adaptations occur during exercise in McArdle disease.

四妙勇安汤含药血清对 ox-LDL 诱导的泡沫化巨噬细胞活化与自噬的影响

目的:探究四妙勇安汤含药血清对ox-LDL诱导的泡沫化巨噬细胞活化与自噬的影响,并探讨其抗动脉粥样硬化(AS)的作用机制。方法:灌胃给予SD大鼠不同剂量四妙勇安水煎液制备含药血清。油红O染色观察泡沫化巨噬细胞脂滴变化;CCK-8法观察含药血清对泡沫巨噬细胞活化的影响;ELISA检测炎症性细胞因子IL-6、IL-10和IFN-γ表达;透射电镜观察细胞自噬水平;免疫荧光标记法检测LC3Ⅱ表达;RT-PCR及Western blot检测细胞AMPK/mTOR/p70S6K通路相关因子表达变化。结果:油红O染色显示,ox-LDL干预后胞质内可见大量橘红色脂滴;CCK-8显示浓度30%以下的含药血清干预泡沫化巨噬细胞OD值无明显变化(P>0.05)。与模型组相比,含药血清刺激后,IL-6、IFN-γ表达降低,IL-10表达升高(P<0.05),含药血清组及雷帕霉素组细胞自噬小体形成增加,LC3Ⅱ、AMPK表达提高,mTOR、p70S6K表达降低(P<0.05)。结论:四妙勇安汤含药血清可调节ox-LDL诱导的泡沫化巨噬细胞活化以及AMPK/mTOR/p70S6K信号通路,抑制炎...