G-CSF/SCF exert beneficial effects via anti-apoptosis in rabbits with steroid-associated osteonecrosis

Objectives

Osteonecrosis is also known as avascular necrosis, and two types of cell death are included in the pathogenesis of osteonecrosis: necrosis and apoptosis. Apoptosis in the osteonecrosis of femoral head is thought to be the key determinant of glucocorticoid-induced cortical bone loss. The present study was implemented to evaluate the anti-apoptotic effect of Granulocyte colony-stimulating factor and stem cell factor (G-CSF/SCF) in rabbits with steroid-induced osteonecrosis.

Methods

In the experiment, osteonecrosis was induced by low-dose lipopolysaccharide and subsequent pulsed high-dose methylprednisolone. Rabbits in preventive medicine group were treated with100 μg/kg/d G-CSF and 25 μg/kg/d SCF. Then hematological and histomorphometric methods were used to investigate the treatment effects of osteonecrosis. Apoptosis was assessed via quantitative TUNEL staining and activated caspase-3 immunostaining and immunoblotting.

Results

The results showed that G-CSF/SCF treatment could increase the secretion of serum osteocalcin, but inhibit the expression of serum tartrate-resistant acid phosphatase (TRAP5b). The incidence of osteonecrosis was significantly decreased in Preventive group when compared with Steroid group (42.1% vs. 88.2%). Histomorphometric analysis showed that G-CSF/SCF pre-disposal treatment was able to increase trabecular mineral appositional rate (MAR) and bone formation rate (BFR). Quantitative TUNEL and activated caspase-3 levels showed lower apoptosis in the Preventive group.

Conclusions

In conclusion, G-CSF/SCF treatment could inhibit caspase-3-dependent apoptosis in osteocytes to exert beneficial effects in preventing steroid-induced ON in rabbit models.     

心房颤动患者心房组织AMPK/PGC-1a通路表达改变的研究

目的 探讨心房颤动（房颤）患者心房肌组织中AMPK/PGC-1α信号通路表达是否改变,探究该通路在在房颤过程中的作用。方法 选择2018年12月至2019年11月在我科行心脏手术的患者76例,根据术前24 h动态心电图及病史分为房颤组（AF,41例）和窦性组（SR,35例）,术中切除左心耳组织留存。使用蛋白质印迹法（western blot,WB）检测心耳组织中AMPK、PGC-1α、NRF1、TFAM的表达量水平。免疫组织化学染色定量左心耳组织TFAM水平。Logistic回归分析AMPK、PGC-1α、NRF1、TFAM的表达水平与术后早期房颤之间的关系。结果 WB结果显示,与窦性心率患者相比,房颤患者左心耳组织内的AMPK、PGC-1α、NRF1、TFAM的表达明显降低（AMPK: 0.75±0.27 VS 0.47±0.43, PGC-1α:0.55±0.10 VS 0.35±0.10, NRF1:0.67±0.11 VS 0.46±0.15, TFAM:0.88±0.19 VS 0.58±0.30,P均<0.05）。免疫组化结果显示房颤患者的左心耳TFAM水平较窦性患者明显降低（8.86±2.13 VS 5.95±2.53, P<0.05）。Logistic回归分析显示TFAM为术后早期房颤的影响因素（b=-0.55, P<0.05）补充数据,低水平TFAM会增加术后新发房颤的风险。结论 AMPK/PGC-1α信号通路参与了房颤过程,其表达在房颤心患者房内降低。TFAM为术后早期房颤的相关因素,低水平TFAM会增加术后发生房颤的风险。     

重组人肿瘤坏死因子相关弱凋亡诱导因子对小鼠主动脉内皮舒张功能及凝血相关因子的影响

目的 采用重组人肿瘤坏死因子相关弱凋亡诱导因子（rhTWEAK）经腹腔注射,诱导血管内皮损伤模型,观察rhTWEAK对小鼠主动脉内皮舒张功能和凝血相关因子的影响。方法 3～4周龄C57BL小鼠32只,随机分成4组,每组8只,腹腔注射各药物：①rhTWEAK组：rhTWEAK按5 μg/（kg·d）的量溶于生理盐水,共0.3 mL,腹腔注射,连续注射7天;②rhTWEAK＋抗rhTWEAK组：先给予抗rhTWEAK腹腔注射,15 min后再给予rhTWEAK注射;③IgG组：给予小鼠非特异性IgG腹腔注射;④对照组：给予0.3 mL生理盐水注射。分别在干预1周后眼球取血,分离上清;取小鼠胸主动脉段进行血管舒张功能的检测。酶联免疫吸附法检测血浆中内皮型一氧化氮合酶（eNOS）、高敏C反应蛋白（hs-CRP）、一氧化氮（NO）、组织因子（TF）、组织因子途径抑制物（TFPI）含量。结果 ①与对照组、rhTWEAK＋抗rhTWEAK组、IgG组相比,rhTWEAK组内皮依赖性血管舒张功能、血浆中eNOS、NO、TFPI水平明显降低,TF水平明显升高,均有统计学意义（均P<0.05）;血浆中hs-CRP含量未见明显改变（P>0.05）;②rhTWEAK组、IgG组与对照组相比,血管内皮舒张功能、血浆中NO、TF、TFPI、eNOS、hs-CRP含量变化均无统计学差异（均P>0.05）。结论 rhTWEAK可诱导内皮功能紊乱和凝血相关因子含量的改变,这可能是TWEAK参与动脉粥样硬化早期血管内皮损害的机制。     

法舒地尔通过Rho-ROCK通路抑制高糖诱导的单核细胞与内皮细胞黏附

目的观察Rho激酶抑制剂法舒地尔能否抑制高糖诱导的单核细胞(THP-1)与人脐静脉内皮细胞黏附,初步探讨其潜在机制。方法使用荧光显微镜观察荧光标记的THP-1与人脐静脉内皮细胞黏附。血管细胞黏附分子1和单核细胞趋化蛋白1的mRNA及蛋白表达水平分别通过RT-PCR、Western blot检测。使用Western blot检测RhoA、ROCK-1、p-MYPT及MYPT蛋白表达水平变化。结果法舒地尔显著抑制高糖诱导的THP-1与人脐静脉内皮细胞黏附,并呈剂量依赖性,其中,低浓度法舒地尔(10-6 mmol/L)干预24 h黏附减少约33.4%,高浓度法舒地尔(10-5 mmol/L)干预24 h黏附减少约42.8%(P值均0.05),干预12 h组趋势相同。法舒地尔显著减低高糖诱导的人脐静脉内皮细胞血管细胞黏附分子1及单核细胞趋化蛋白1的mRNA及蛋白表达水平,并呈时间依赖性和剂量依赖性。高糖显著增加p-MYPT/MYPT比值,而法舒地尔减弱高糖对p-MYPT/MYPT比值的影响,抑制Rho/RCOK通路激活。结论法舒地尔抑制高糖诱导的THP-1与人脐静脉内皮细胞黏附,减低高糖诱导的人脐静脉内皮细胞血管细胞黏附分子1和单核细胞趋化蛋白1的表达,减少高糖诱导的Rho/RCOK通路激活,提示法舒地尔可能成为新的糖尿病大血管病变治疗药物。     

莫沙必利对阿司匹林致大鼠急性胃黏膜损伤的保护作用

研究显示促胃肠动力药物莫沙必利对胃黏膜损伤具有一定的保护作用。目的：研究不同剂量莫沙必利对阿司匹林致大鼠急性胃黏膜损伤的保护作用及其机制。方法：将50只大鼠随机分为阴性对照组、单纯损伤组以及不同剂量莫沙必利干预组（0．25mg／kg、0．50mg／kg、0．75mg／kg）。干预组大鼠以不同剂量莫沙必利灌胃行预处理,以150mg／kg阿司匹林灌胃制备急性胃黏膜损伤模型。实验第4d,处死大鼠。评估大鼠胃黏膜损伤指数和组织学变化,以免疫组化法检测Occludin蛋白分布,蛋白质印迹法检测Occludin、ZO．1以及磷酸化ERK（p-ERK）、磷酸化JNK（p-JNK）和磷酸化p38（p-p38）蛋白表达。结果：与单纯损伤组相比,各莫沙必利干预组胃黏膜损伤指数均明显降低（P〈0．05）;胃黏膜组织学明显改善;胃黏膜Occludin、ZO-1蛋白表达呈剂量依赖性升高（P〈0．05）;胃黏膜p-ERK、p-p38蛋白表达呈剂量依赖性降低（P〈0．05）;而胃黏膜p-JNK蛋白表达无明显差异。结论：莫沙必利对阿司匹林致大鼠急性胃黏膜损伤具有明显保护作用,其机制可能为降低MAPKs信号通路中ERK和p38蛋白磷酸化程度,并上调胃黏膜紧密连接蛋白Occludin和ZO-1表达,从而改善胃黏膜屏障的功能。     

临床护理路径对核磁共振增强检查患者满意度的影响

目的：探讨如何将临床护理路径应用于核磁共振增强检查,使其形成模式化并确保更高的患者满意度。方法：将实施临床护理路径前后进行核磁共振增强检查的患者分别设为对照组和实验组。采用技术评价量表和患者满意度问卷调查,比较护士技术水平和患者满意度。结果：实施临床护理路径管理模式后,患者检查准备不足现象减少,护理投诉与纠纷明显减少（P < 0.05）。患者对MRI增强检查过程中护士主动沟通、健康教育、检查后处置、部门间协作的满意度提升明显（P < 0.05）。结论：在核磁共振增强检查过程中应用临床护理路径管理模式提升了患者满意度,对改进临床管理质量有一定借鉴。     

Monomethylarsonous acid inhibited endogenous cholesterol biosynthesis in human skin fibroblasts

Human exposure to arsenic in drinking water is a widespread public health concern, and such exposure is known to be associated with many human diseases. The detailed molecular mechanisms about how arsenic species contribute to the adverse human health effects, however, remain incompletely understood. Monomethylarsonous acid [MMA(III)] is a highly toxic and stable metabolite of inorganic arsenic. To exploit the mechanisms through which MMA(III) exerts its cytotoxic effect, we adopted a quantitative proteomic approach, by coupling stable isotope labeling by amino acids in cell culture (SILAC) with LC-MS/MS analysis, to examine the variation in the entire proteome of GM00637 human skin fibroblasts following acute MMA(III) exposure. Among the ~ 6500 unique proteins quantified, ~ 300 displayed significant changes in expression after exposure with 2 μM MMA(III) for 24 h. Subsequent analysis revealed the perturbation of de novo cholesterol biosynthesis, selenoprotein synthesis and Nrf2 pathways evoked by MMA(III) exposure. Particularly, MMA(III) treatment resulted in considerable down-regulation of several enzymes involved in cholesterol biosynthesis. In addition, real-time PCR analysis showed reduced mRNA levels of select genes in this pathway. Furthermore, MMA(III) exposure contributed to a distinct decline in cellular cholesterol content and significant growth inhibition of multiple cell lines, both of which could be restored by supplementation of cholesterol to the culture media. Collectively, the present study demonstrated that the cytotoxicity of MMA(III) may arise, at least in part, from the down-regulation of cholesterol biosynthesis enzymes and the resultant decrease of cellular cholesterol content.