目的探讨载脂蛋白A-Ⅰ模拟肽左旋-氨基酸(L-4F)对肥胖合并心肌梗死大鼠心功能的影响及其可能机制。方法选择7周龄雄性SD大鼠60只,对照组12只大鼠给予普通饲料喂养,其余48只大鼠给予高脂饲料喂养8周,随机分为肥胖组,心肌梗死组,L-4F组,...目的探讨载脂蛋白A-Ⅰ模拟肽左旋-氨基酸(L-4F)对肥胖合并心肌梗死大鼠心功能的影响及其可能机制。方法选择7周龄雄性SD大鼠60只,对照组12只大鼠给予普通饲料喂养,其余48只大鼠给予高脂饲料喂养8周,随机分为肥胖组,心肌梗死组,L-4F组,血红素氧化酶1(HO-1)抑制剂(SnMP)组,每组12只,后3组大鼠给予结扎冠状动脉左前降支,建立肥胖合并心肌梗死大鼠模型。干预8周后行超声心动图、血流动力学检查,包括左心室收缩末期内径(LVESD)、左心室舒张末期内径(LVEDD)、LVEF、左心室短轴缩短率(LVFS)、左心室收缩压(LVSP)、左心室舒张末压(LVEDP),计算左心室压力最大上升及下降速率(±dp/dt_(max)),组织标本采用苏木精-伊红染色和Masson染色,ELISA检测血清脂联素,实时荧光定量PCR和Western blot检测相关基因表达,包括内质网应激蛋白(Chop)、葡萄糖调节蛋白78(GRP78)及磷酸化类蛋白激酶内质网激酶(PERK)蛋白。结果与对照组比较,肥胖组LVESD、LVEDD、LVSP、LVEDP、Chop及磷酸化PERK明显升高,LVEF、LVFS、-dp/dt_(max)、HO-1、脂联素水平明显降低;与心肌梗死组比较,L-4F组LVESD、LVEDD、LVSP、LVEDP、Chop、GRP78及磷酸化PERK明显降低,LVEF、LVFS、±dp/dt_(max)、HO-1、脂联素明显升高(P<0.05,P<0.01);与L-4F组比较,SnMP组LVESD、LVEDD、LVSP、LVEDP明显升高,Chop、GRP78及磷酸化PERK明显升高[1.14±0.15 vs 0.80±0.09,P<0.05;5.04±0.33 vs 2.96±0.22,P<0.05;16.79±0.89 vs 5.18±0.73,P<0.01],LVEF、LVFS、±dp/dt_(max)、HO-1、脂联素水平明显降低(P<0.05,P<0.01)。结论L-4F通过激活肥胖合并心肌梗死大鼠HO-1-脂联素轴,抑制内质网应激,降低心肌细胞毒性,抑制心脏重构,改善大鼠心功能。展开更多
A two-photon ratiometric fluorescent sensor for Cu^+ in endoplasmic reticulum(ER), CNSB, was developed via coumarin/ASBD integration based on FRET mechanism. In solution, CNSB shows reversible, highly-specific ratiome...A two-photon ratiometric fluorescent sensor for Cu^+ in endoplasmic reticulum(ER), CNSB, was developed via coumarin/ASBD integration based on FRET mechanism. In solution, CNSB shows reversible, highly-specific ratiometric response to Cu^+ .Moreover, CNSB exhibits suitable K_d value, suggesting the possibility of detecting Cu^+ in the living cells. The probe can enter the MCF-7 cells easily and specifically locates in the ER. The highly specific ratiometric response of CNSB toward Cu^+ in MCF-7 cells provides the sensor the capacity to visualize both exogenous and endogenous Cu^+ in the ER via fluorescence imaging.Next, CNSB was utilized to detect the fluctuation and distribution of Cu^+ under ER stress in MCF-7 cells, which confirmed directly the relationship between Cu^+ enhancement and ER stress. Meanwhile, the two-photon ability of coumarin facilitated the sensor to visualize Cu^+ fluctuation via two-photon fluorescence imaging. In addition, the spatial distribution of Cu^+ in the heart slice of the 14-day-old rat was demonstrated using CNSB. This study demonstrates the promising potential of CNSB in clarifying the Cu^+ -dependent signaling in the ER stress-related diseases.展开更多
文摘目的探讨载脂蛋白A-Ⅰ模拟肽左旋-氨基酸(L-4F)对肥胖合并心肌梗死大鼠心功能的影响及其可能机制。方法选择7周龄雄性SD大鼠60只,对照组12只大鼠给予普通饲料喂养,其余48只大鼠给予高脂饲料喂养8周,随机分为肥胖组,心肌梗死组,L-4F组,血红素氧化酶1(HO-1)抑制剂(SnMP)组,每组12只,后3组大鼠给予结扎冠状动脉左前降支,建立肥胖合并心肌梗死大鼠模型。干预8周后行超声心动图、血流动力学检查,包括左心室收缩末期内径(LVESD)、左心室舒张末期内径(LVEDD)、LVEF、左心室短轴缩短率(LVFS)、左心室收缩压(LVSP)、左心室舒张末压(LVEDP),计算左心室压力最大上升及下降速率(±dp/dt_(max)),组织标本采用苏木精-伊红染色和Masson染色,ELISA检测血清脂联素,实时荧光定量PCR和Western blot检测相关基因表达,包括内质网应激蛋白(Chop)、葡萄糖调节蛋白78(GRP78)及磷酸化类蛋白激酶内质网激酶(PERK)蛋白。结果与对照组比较,肥胖组LVESD、LVEDD、LVSP、LVEDP、Chop及磷酸化PERK明显升高,LVEF、LVFS、-dp/dt_(max)、HO-1、脂联素水平明显降低;与心肌梗死组比较,L-4F组LVESD、LVEDD、LVSP、LVEDP、Chop、GRP78及磷酸化PERK明显降低,LVEF、LVFS、±dp/dt_(max)、HO-1、脂联素明显升高(P<0.05,P<0.01);与L-4F组比较,SnMP组LVESD、LVEDD、LVSP、LVEDP明显升高,Chop、GRP78及磷酸化PERK明显升高[1.14±0.15 vs 0.80±0.09,P<0.05;5.04±0.33 vs 2.96±0.22,P<0.05;16.79±0.89 vs 5.18±0.73,P<0.01],LVEF、LVFS、±dp/dt_(max)、HO-1、脂联素水平明显降低(P<0.05,P<0.01)。结论L-4F通过激活肥胖合并心肌梗死大鼠HO-1-脂联素轴,抑制内质网应激,降低心肌细胞毒性,抑制心脏重构,改善大鼠心功能。
基金supported by the National Basic Research Program of China (2015CB856300)the National Natural Science Foundation of China (21571099, 21731004)the Natural Science Foundation of Jiangsu (BK20150054)
文摘A two-photon ratiometric fluorescent sensor for Cu^+ in endoplasmic reticulum(ER), CNSB, was developed via coumarin/ASBD integration based on FRET mechanism. In solution, CNSB shows reversible, highly-specific ratiometric response to Cu^+ .Moreover, CNSB exhibits suitable K_d value, suggesting the possibility of detecting Cu^+ in the living cells. The probe can enter the MCF-7 cells easily and specifically locates in the ER. The highly specific ratiometric response of CNSB toward Cu^+ in MCF-7 cells provides the sensor the capacity to visualize both exogenous and endogenous Cu^+ in the ER via fluorescence imaging.Next, CNSB was utilized to detect the fluctuation and distribution of Cu^+ under ER stress in MCF-7 cells, which confirmed directly the relationship between Cu^+ enhancement and ER stress. Meanwhile, the two-photon ability of coumarin facilitated the sensor to visualize Cu^+ fluctuation via two-photon fluorescence imaging. In addition, the spatial distribution of Cu^+ in the heart slice of the 14-day-old rat was demonstrated using CNSB. This study demonstrates the promising potential of CNSB in clarifying the Cu^+ -dependent signaling in the ER stress-related diseases.
