血清趋化素水平与代谢综合征的相关性研究

目的 探讨血清趋化素（Chemerin）水平与MS的相关性. 方法 选取非MS（Non-MS）组57例,MS组117例及健康对照（NC）组90名,按Chemerin水平从低到高分为Ter1、Ter2和Ter3亚组.所有研究对象行75 g OGTT和胰岛素释放试验,检测血脂、血清Chemerin、高敏C反应蛋白（hsC-RP）等相关生化指标. 结果 MS组血清Chemerin水平高于Non-MS组和NC组（P＜0.01）.从Ter1到Ter3亚组,BMI、WC、WHR、SBP、FPG、2 hPG、HbA1 c、FIns、HOMA-IR、TG、hsC-RP水平依次升高,HDL-C水平依次降低,MS的患病率依次增加（P＜0.05）.Chemerin与BMI、WC、WHR、SBP、FPG、2 hPG、HbA1 c、FIns、2 hIns、HOMA-IR、TG及hsC-RP呈正相关（P＜0.05）,与HDL-C、胰岛β细胞功能指数（HOMA-β）呈负相关（P＜0.01）.Logistic逐步回归分析显示,Chemerin是MS的独立危险因素（OR=2.197,P＜0.01）.受试者工作曲线（ROC）曲线提示Chemerin预测MS的界值为72.4 ng/ml.结论 Chemerin与MS的发生相关,可作为MS的独立预测指标之一.     

Takotsubo cardiomyopathy has a unique cardiac biomarker profile: NT-proBNP/myoglobin and NT-proBNP/troponin T ratios for the differential diagnosis of acute coronary syndromes and stress induced cardiomyopathy

Background

Takotsubo cardiomyopathy (TC) usually is not recognized until heart catheterization reveals typical wall motion abnormalities in the absence of significant coronary artery disease. It was our aim to identify TC by its unique cardiac biomarker profile at an early stage and, preferably, with non-invasive procedures only.

Methods

Ratios of N-terminal prohormone of brain natriuretic peptide (NT-proBNP) and myoglobin, NT-proBNP and troponin T (TnT), NT-proBNP and creatinekinase-MB (CK-MB) were compared in patients with TC (n = 39), patients with ST-elevation myocardial infarction (STEMI, n = 48) and patients with non-ST-elevation myocardial infarction (NSTEMI, n = 34). Biomarkers were recorded serially at admission and at the three consecutive days. Optimal cut-off values to distinguish TC from STEMI and NSTEMI were calculated with receiver operator characteristic (ROC) curves.

Results

At admission a NT-proBNP (ng/l)/myoglobin (μg/l) ratio of 3.8, distinguished TC from STEMI (sensitivity: 89%, specificity: 90%), while a NT-proBNP (ng/l)/myoglobin (μg/l) ratio of 14 separated well between TC and NSTEMI (sensitivity: 65%, specificity: 90%). Best differentiation of TC and ACS was possible with the ratio of peak levels of NT-proBNP (ng/l)/TnT (μg/l). A cut-off value of NT-proBNP (ng/l)/TnT (μg/l) ratio of 2889, distinguished TC from STEMI (sensitivity: 91%, specificity: 95%), while a NT-proBNP (ng/l)/TnT (μg/l) ratio of 5000 separated well between TC and NSTEMI (sensitivity: 83%, specificity: 95%).

Conclusions

TC goes along with a singular cardiac biomarker profile, which might be useful to identify patients with TC among patients presenting with acute coronary syndromes (ACS).     

mTOR inhibition with rapamycin causes impaired insulin signalling and glucose uptake in human subcutaneous and omental adipocytes

Rapamycin is an immunosuppressive agent used after organ transplantation, but its molecular effects on glucose metabolism needs further evaluation. We explored rapamycin effects on glucose uptake and insulin signalling proteins in adipocytes obtained via subcutaneous (n=62) and omental (n=10) fat biopsies in human donors. At therapeutic concentration (0.01 μM) rapamycin reduced basal and insulin-stimulated glucose uptake by 20-30%, after short-term (15 min) or long-term (20 h) culture of subcutaneous (n=23 and n=10) and omental adipocytes (n=6 and n=7). Rapamycin reduced PKB Ser473 and AS160 Thr642 phosphorylation, and IRS2 protein levels in subcutaneous adipocytes. Additionally, it reduced mTOR-raptor, mTOR-rictor and mTOR-Sin1 interactions, suggesting decreased mTORC1 and mTORC2 formation. Rapamycin also reduced IR Tyr1146 and IRS1 Ser307/Ser616/Ser636 phosphorylation, whereas no effects were observed on the insulin stimulated IRS1-Tyr and TSC2 Thr1462 phosphorylation. This is the first study to show that rapamycin reduces glucose uptake in human adipocytes through impaired insulin signalling and this may contribute to the development of insulin resistance associated with rapamycin therapy.     

Localization of masticatory motoneurons in the trigeminal motor nucleus of shrew and pig,with emphasis on the innervation ratio in the shrew

Objectives:We investigated the topographical representation of the masticatory muscles, primarily in the trigeminal motor nucleus (TMN) of the house musk shrew (Suncus murinus) and miniature pig, in a series of mammalian comparative anatomical studies. Additionally, correlations between motoneurons and muscles were investigated in order to examine the functionality of each muscle in the trigeminal motor system.Methods:Motoneurons were labeled using horseradish peroxidase (HRP) injection into each muscle innervated by the trigeminal nerve. In the shrew, the sizes and numbers of HRP-labeled neurons, muscle weight, and numbers of muscle fibers were measured in the innervated muscles, and correlation coefficients for the relationships among these parameters were calculated.Results:The motoneuron cluster of each muscle was arranged in the TMN in a manner similar to that observed in other previously reported animals, but the distribution of the lateral pterygoid motoneurons varied between species. In addition, considerably higher overlap was observed in each pig jaw-closer motoneuron cluster compared with other animals. The approximate innervation ratios were as follows: masseter, 337; temporal, 322; anterior digastric, 137; medial pterygoid, 110; lateral pterygoid, 79; mylohyoid, 42; tensor veli palatini, 42; transverse mandibular, 16; and tensor tympani muscles, 5.ConclusionsThe distribution pattern of the masticatory motoneurons was clearly observed in the shrew and pig TMN, and various correlations between the motoneuron and innervated muscles were determined.     

The Effect of K-ATP Channel Blockage During Erythropoietin Treatment in Renal Ischemia-Reperfusion Injury

ATP dependent K channels (K-ATP) take part in the Erythropoietin (EPO) induced cardioprotection but these channel activations have role in cytoprotective role of EPO in the renal ischemia reperfusion (IR) damage is still unknown. For this purpose rats were pretreated with EPO (500 IU/kg) and/or K-ATP channel blocker glibenclamide (40mM/kg) i.p. before bilateral renal IR damage. Renal tissues were used for histological examination and measurement of caspase-3 and TNF-α levels. Renal functions were evaluated by glomerular filtration rate (GFR) fractional excretion of sodium (FENa) and potassium (FEK). Renal TNF-α and caspase-3 levels were decreased in both glibenclamide and EPO-treated IR rats compared to untreated rats. The protection afforded by the pretreatment with EPO alone was greater than that of administering glibenclamide alone. Application of glibenclamide at the same time partly abolished the cytoprotective effect of EPO treatment. K-ATP mediated cytoprotection is not the main mechanism of protective effect of EPO.     

甜菜碱对大鼠心肌缺血再灌注损伤炎症及心肌细胞凋亡的影响

目的 探讨甜菜碱对大鼠心肌缺血再灌注（IR）损伤的影响及发生机制。方法 选用成年雄性SD大鼠18只,采用随机数字表分为假手术组（SO组）、缺血再灌注组（IR组）及甜菜碱组（450 mg/kg灌胃）,每组6只大鼠。SO组：开胸,前降支动脉下穿线不结扎,IR组和甜菜碱组：开胸,缺血30 min,再灌注4 h。ELISA法检测并比较3组大鼠心肌损伤标记物乳酸脱氢酶（LDH）、肌酸激酶b（CK-Mb）和肌钙蛋白I（cTnI）和检测炎症因子（HMGB1、IL-17A、IL-6以及TNF-α）的表达。Western Blot法检测并比较3组大鼠心肌组织凋亡蛋白（caspase-3,Bcl-2和Bax）的相对表达量。结果 与SO组比较,IR组中心肌损伤标记物（CK、LDH和cTnI）、炎症因子和凋亡蛋白的表达均增高,差异均有统计学意义（P<0.05）。与IR比较,甜菜碱组心肌损伤标记物、炎症因子和凋亡蛋白的表达下降,抗凋亡蛋白Bcl-2的表达增加,差异有统计学意义（P<0.05）。结论 甜菜碱可以通过抑制炎症反应和心肌细胞凋亡减轻大鼠心肌IR损伤。