葡萄糖对豚鼠心室肌细胞跨膜离子电流的影响

目的观察葡萄糖对豚鼠心室肌细胞膜APD,IK1,IK,ICa-L的影响.方法采用全细胞膜片技术记录单个豚鼠心室肌细胞膜的动作电位时程和离子电流.比较0、10和20mmol·L-1葡萄糖对心室肌细胞跨膜离子电流的作用.结果(1)与10 mmol·L-1葡萄糖相比,0和20mmol·L-1均可使豚鼠心室肌细胞的APD缩短(P＜0.05);(2)在细胞外葡萄糖浓度为10 mmol·L-1时,内向整流钾电流IK1的电流密度最大,标准化I-V曲线显示0和20mmol·L-1葡萄糖均可抑制IK1,并使I-V曲线左移,其翻转电位从-72.4移至-64.6 mV;(3)与mmol·L-1葡萄糖相比,0和20mmol·L-1葡萄糖均可增加ICa-L的电流幅度和电流密度.当钳制电位为10 mV,细胞外葡萄糖浓度为0 mmol·L-1时,ICa-L的电流密度为(-8.03±0.82)pA/pF(n=8),而10mmol·L-1和20mmol·L-1葡萄糖分别使电流密度增加为(-5.45±0.67)pA/pF和(-6.50±0.56)pA/pF;(4)当钳制电压为 70mV,细胞外葡萄糖浓度为0、10和20 mmol·L-1时,IK的电流密度分别为(18.96±2.86)pA/pF,(8.66±1.87)pA/pF,(15.32±3.12)pA/pF.结论细胞外不同浓度的葡萄糖可使豚鼠心室肌细胞APD,IK1,IK,ICa-L发生改变.细胞外葡萄糖浓度为0和20mmol·L-1对细胞膜离子电流产生相似的影响.     

荆豆凝集素修饰脂质体对小鼠口服吸收胰岛素的促进作用

目的研究荆豆凝集素(UEA1)修饰的胰岛素脂质体在小鼠胃肠道的吸收作用。方法采用碳二亚胺偶联法制备荆豆凝集素修饰的磷脂酰乙醇胺(PE)，将PE-UEA1参入胰岛素脂质体中制成凝集素修饰脂质体，并证实UEA1凝集活性不受影响。分别对正常小鼠及糖尿病模型小鼠灌胃给予350 u·kg^-1胰岛素的修饰脂质体溶液，用葡萄糖酶试剂盒测定小鼠血糖，并与同剂量普通胰岛素脂质体比较。结果对于正常小鼠，荆豆凝集素修饰脂质体在4 h使血糖降至初始水平的(84±15)%，8 h降至(78±11)%，12 h为(90±12)%。胰岛素普通脂质体几乎没有降糖作用，与生理盐水对照组相当。对于糖尿病模型小鼠，荆豆凝集素修饰脂质体在4 h使血糖降至初始水平的(73±7)%，8 h降至(74±9)%，12 h为(86±9)%。结论荆豆凝集素修饰的脂质体可能通过与M细胞表面特异性受体的结合促进大分子药物的胃肠吸收。     

The Effect of Resveratrol Supplementation on Cardio‐Metabolic Risk Factors in Patients with Type 2 Diabetes: A Randomized,Double‐Blind Controlled Trial

The aim of the present randomized controlled trial was to evaluate the effect of a micronized resveratrol supplement on glycemic status, lipid profile, and body composition in patients with type 2 diabetes mellitus (T2DM). A total of 71 overweight patients with T2DM (body mass index ranged 25–30) were randomly assigned to receive 1000 mg/day trans‐resveratrol or placebo (methyl cellulose) for 8 weeks. Anthropometric indices and biochemical indices including lipid and glycemic profile were measured before and after the intervention. In adjusted model (age, sex, and baseline body mass index), resveratrol decreased fasting blood sugar (?7.97±13.6 mg/dL, p=0.05) and increased high density lipoprotein (3.62±8.75 mg/dL, p=0.01) levels compared with placebo. Moreover, the mean difference in insulin levels reached significance (?0.97±1.91, μIU/mL, p= 0.02). However, no significant differences were observed for anthropometric measures. It was found that 8‐week resveratrol supplementation produced useful effects on some cardio‐metabolic parameters in patients with T2DM. More studies are needed to confirm these findings.     

高浓度葡萄糖对体外培养大鼠Müller细胞P2Y2受体的影响

目的:观察高浓度葡萄糖对体外培养的大鼠视网膜Müler细胞P2Y2受体表达的影响。方法:用改进的酶消化法纯化培养并用胶质原纤维酸性蛋白(GFAP)和谷氨酰胺合成酶(GS)鉴定大鼠Müller细胞。分别在对照组(5.5mmol/L)与高糖组(10,25,50mmol/L)中孵育24h和72h,通过免疫荧光及荧光强度半定量分析检测Müller细胞中P2Y2受体表达的变化。结果:纯化培养到第3~4代的Müller细胞,经鉴定纯度大于90%,表达GFAP和GS。在24h,10,25,50mmol/L组的荧光强度分别为31.05±7.06,59.17±11.42和84.11±12.72,与对照组(26.60±5.15)相比较均明显增高(P<0.01)。而在72h,仅25和50mmol/L组的荧光强度明显强于对照组(P<0.01)。结论:高浓度葡萄糖上调大鼠视网膜Müller细胞P2Y2受体的表达,提示这一受体可能参与糖尿病视网膜病变过程。     

高糖对人晶状体上皮细胞凋亡的作用

目的:研究不同浓度的高糖(HG)对人晶状体上皮细胞凋亡的作用。方法:用不同浓度的HG诱导人晶状体上皮细胞凋亡,处理组:DMEM+HG;对照组:DMEM。用四甲基偶氮唑盐(MTT)比色法检测人晶状体上皮细胞的生长活性;原位末端核苷标记(TUNEL)法检测细胞凋亡的凋亡指数(AI),并在电镜下观察TUNEL染色阳性细胞的形态及分布。结果:HG可抑制人晶状体上皮细胞生长,诱导细胞的凋亡,并呈剂量及时间依赖性,HG诱导组细胞凋亡率明显高于正常组(P<0.01)。TUNEL染色法在电镜下观察到HG诱导24h后,TUNEL染色阳性细胞核固缩或碎裂呈棕黄色,细胞大小不一;而TUNEL染色阴性细胞着色均匀,大小均一。结论:高糖具有促使人晶状体上皮细胞凋亡形成的作用,尤其是在120~150mmol/L浓度范围内。     

Neonatal and fetal exposure to trans-fatty acids retards early growth and adiposity while adversely affecting glucose in mice

Industrially produced trans-fatty acids (TFAs) consumed in Western diets are incorporated into maternal and fetal tissues and are passed linearly to offspring via breast milk. We hypothesized that TFA exposure in utero and during lactation in infants would promote obesity and poor glycemic control as compared with unmodified fatty acids. We further hypothesized that in utero exposure alone may program for these outcomes in adulthood. To test this hypothesis, we fed female C57/BL6 mice identical Western diets that differed only in cis- or trans-isomers of C18:1 and then aimed to determine whether maternal transfer of TFAs through pregnancy and lactation alters growth, body composition, and glucose metabolism. Mice were unexposed, exposed during pregnancy, during lactation, or throughout pregnancy and lactation to TFA. Body weight and composition (by computed tomography) and glucose metabolism were assessed at weaning and adulthood. Trans-fatty acid exposure through breast milk caused significant early growth retardation (P < .001) and higher fasting glucose (P = .01), but insulin sensitivity was not different. Elevated plasma insulin-like growth factor-1 in mice consuming TFA-enriched milk (P = .02) may contribute to later catch-up growth and leanness and preserved peripheral insulin sensitivity observed in these mice. Mice exposed to TFA in utero underwent rapid early neonatal growth with TFA-free breast milk and had significantly impaired insulin sensitivity (P < .05) and greater abdominal fat (P = .01). We conclude that very early catch-up growth resulted in impaired peripheral insulin sensitivity in this model of diet-related fetal and neonatal programming. Trans-fatty acid surprisingly retarded growth and adiposity while still adversely affecting glucose metabolism.     

2型糖尿病胰岛素抵抗与脂代谢关系分析

目的 探讨2型糖尿病胰岛素抵抗（IR）与脂代谢异常之间的关系.方法 测定106例2型糖尿病患者和100例正常对照者空腹血糖（FPG）、空腹胰岛素及脂代谢指标,并进行相关性分析.结果 2型糖尿病组空腹血糖、血清、总胆固醇（TC）、甘油三酯（TG）、低密度脂蛋白胆固醇（LDL-C）、水平明显高于正常对照组（P〈0.01）,高密度脂蛋白胆固醇（HDL-C）水平明显低于正常对照组（P〈0.01）.结论 2型糖尿病患者有高胰岛素血症、胰岛素抵抗和脂代谢异常.     

Urinary phthalate metabolites and metabolic syndrome in U.S. adolescents: Cross-sectional results from the National Health and Nutrition Examination Survey (2003–2014) data

Objective

There is limited research on the association between phthalates and metabolic syndrome (MetS). Among adolescents, phthalate exposure, which can occur from multiple sources, has been linked to several risk factors for MetS. The objective was to investigate the association between urinary phthalate metabolite concentrations (i.e., mono-ethyl phthalate (MEP), mono-n-butyl phthalate (MnBP), mono-isobutyl phthalate (MiBP), mono-benzyl phthalate (MBzP), mono-(3-carboxylpropyl) phthalate (MCPP), and di(2-ethylhexyl phthalate (DEHP)) and MetS in adolescents aged 12–19 years using the National Health and Nutrition Examination Survey (NHANES) data (2003–2014). A secondary aim was to assess if observed associations varied by a measure of socioeconomic status, economic adversity, which was defined using parental income and educational attainment as well as household food security.

镇心省睡益智方及其精油对AD模型小鼠学习记忆的影响

目的:观察镇心省睡益智方水提液及其精油对β淀粉样前体蛋白基因/早老素基因(APP/PS1)双转基因小鼠学习记忆的影响并探讨其可能机制。方法:采用APP/PS1双转基因痴呆小鼠及同月龄相同遗传背景C57BL/6JNju小鼠2种小鼠。C57BL/6JNju小鼠作为正常组,APP/PS1双转基因痴呆小鼠随机分为模型组,镇心省睡益智方精油低、高质量浓度组(12.13,48.50 mg·L~(-1)),镇心省睡益智方水提液组(0.46 g·kg~(-1)),每组12只。每天给药1次,连续给药22 d。给药结束后采用跳台实验、Morris水迷宫实验对小鼠行为学能力进行检测,采用尼氏染色观察海马CA1区神经元变化,采用硫磺素(Th S)染色观察海马DG区老年斑(SP)沉积,采用免疫组化法检测小鼠脑组织中葡萄糖转运蛋白1(GLUT1),胰岛素受体底物-1(IRS-1)的表达,采用酶联免疫吸附测定(ELISA)检测小鼠海马组织中乙酰胆碱(ACH),γ-氨基丁酸(GABA),谷氨酸(GLU)含量的变化。结果:与正常组比较,模型组小鼠跳台实验潜伏期显著缩短,错误次数显著增加(P0.01),Morris水迷宫实验定位航行逃避潜伏期明显延长(P0.05,P0.01),海马CA1区神经元出现缺失,DG区出现明显的老年斑沉积(P0.05),ACH,GLUT1含量均显著下降(P0.01),GABA,GLU水平及IRS-1的表达均显著升高(P0.01);与模型组比较,各给药组均可显著延长小鼠跳台实验潜伏期、减少跳台错误次数(P0.01),明显降低定位航行小鼠逃避潜伏期(P0.05,P0.01),可一定程度保护小鼠海马CA1区神经元,减少DG区老年斑沉积(P0.05,P0.01),明显增加小鼠脑组织中ACH,GLUT1表达(P0.05,P0.01),显著降低GABA,GLU水平及IRS-1的表达(P0.01)。结论:镇心省睡益智方水提液及其精油能够改善APP/PS1小鼠的学习记忆行为,保护神经元,增加脑组织GLUT1的表达,减少脑组织IRS-1的表达,减少老年斑沉积,升高ACH含量,降低GABA,GLU含量,可能是其防治阿尔茨海默症的机制。     

儿童早期发展养育照护体系中的回应性照护

儿童早期发展养育照护体系由儿童健康、足够的营养、安全和保障、回应性照护以及早期学习机会五大内容组成。其中回应性照护是促进儿童早期发展的重要方式,本文从回应性照护的内涵、面临的挑战、实施与评价等方面进行总结回顾,探讨回应性照护对儿童早期发展的影响。