目的:观察泽泻萜类化合物对ApoE基因敲除小鼠实验性动脉粥样硬化肝脏基底膜硫酸乙酰肝素蛋白多糖的调节作用。方法:将8周龄C57/BL小鼠12只设为正常对照组,8周龄ApoE基因缺陷小鼠36只随机分为3组:模型组、中药组、舒降之阳性对照组。正...目的:观察泽泻萜类化合物对ApoE基因敲除小鼠实验性动脉粥样硬化肝脏基底膜硫酸乙酰肝素蛋白多糖的调节作用。方法:将8周龄C57/BL小鼠12只设为正常对照组,8周龄ApoE基因缺陷小鼠36只随机分为3组:模型组、中药组、舒降之阳性对照组。正常对照组、模型组予0.9%生理盐水灌胃,给药组正常人每kg体重的10倍量灌胃90天后,全自动生化仪测定血清血脂含量,用免疫印记法测定各组肝脏基底膜硫酸乙酰肝素蛋白多糖的表达,用Quantity One 6.0软件进行光密度分析。结果:中药组、阳性对照药组与模型组比较,总胆固醇、低密度脂蛋白水平均明显降低。中药组、阳性对照药组肝脏基底膜HSPG表达与模型组比较明显上调,但与正常对照组比较则明显下调。结论:泽泻萜类化合物对apoE-基因敲除高脂饲料喂养所致动脉粥样硬化小鼠具有降低血清总胆固醇、低密度脂蛋白的作用,对该模型小鼠的肝脏基底膜HSPG表达有调节作用。展开更多
Perlecan,a heparan sulfate proteoglycan,acts as a mechanical sensor for bone to detect external loading.Deficiency of perlecan increases the risk of osteoporosis in patients with Schwartz-Jampel Syndrome(SJS)and atten...Perlecan,a heparan sulfate proteoglycan,acts as a mechanical sensor for bone to detect external loading.Deficiency of perlecan increases the risk of osteoporosis in patients with Schwartz-Jampel Syndrome(SJS)and attenuates loading4nduced bone formation in perlecan deficient mice(Hypo).Considering that intracellular calcium[Ca2+]i is an ubiquitous messenger controlling numerous cellular processes including mechanotransduction,we hypothesized that perlecan deficiency impairs bone’s calcium signaling in response to loading.To test this,we performed real-time[Ca2+]i imaging on in situ osteocytes of adult murine tibiae under cyclic loading(8 N,Figure 1).Relative to wild type(WT),Hypo osteocytes showed decreases in the overall[Ca2+]i response rate(-58%),calcium peaks(-33%),cells with multiple peaks(-53%),peak magnitude(-6.8%),and recovery speed to baseline(-23%).RNA sequencing and pathway analysis of tibiae from mice subjected to one or seven days of unilateral loading demonstrated that perlecan deficiency significantly suppressed the calcium signaling,ECM-receptor interaction,and focal adhesion pathways following repetitive loading.Defects in the endoplasmic reticulum(ER)calcium cycling regulators such as Ryr1/ryanodine receptors and Atp2a1/Sercal calcium pumps were identified in Hypo bones.Taken together,impaired calcium signaling may contribute to bone’s reduced anabolic response to loading,underlying the osteoporosis risk for the SJS patients.展开更多
Lens fibre differentiation is a life-long process related with lens transparency, and is particularly intense during development, being related with an FGF-2 antero-posterior gradient at the equator level as the main ...Lens fibre differentiation is a life-long process related with lens transparency, and is particularly intense during development, being related with an FGF-2 antero-posterior gradient at the equator level as the main growth factor involved which has been related with the basal membrane of the lens anlagen known as “Lens capsule”. However the lens fibre differentiation induced by FGF2 depends, as in other biological systems, on the local bioavailability of FGF-2 regulated by their relationship with extracellular matrix molecules as Heparan Sulphate Proteoglycans. Here, we try to clarify how Perlecan (a heparan sulphate proteoglycan specific from basement membranes) is involved in lens fibre differentiation at earliest stages of eye development. Our results show that Perlecan, is a major component in the lens capsule during the earliest stages of lens development in chick embryos being present during lens plate induction, lens vesicle stage and the onset of lens fibre differentiation. In order to demonstrate a direct involvement of HSPG-Perlecan in lens fibre differentiation, we generate depleted lenses by HSPG-Perlecan synthesis disruption and specific enzymatic digestion. The HSPG-Perlecan depleted lens show a significant delay or abolition in the lens fibre differentiation which remains in an immature cells displaying DNA synthesis in the posterior epithelium and a decrease in FGF2 lens expression. These data support the hypothesis that lens capsule HSPG-Perlecan is a key molecule involved in lens fibre differentiation during development, probably by involvement in FGF-2 biodisponibility.展开更多
文摘目的:观察泽泻萜类化合物对ApoE基因敲除小鼠实验性动脉粥样硬化肝脏基底膜硫酸乙酰肝素蛋白多糖的调节作用。方法:将8周龄C57/BL小鼠12只设为正常对照组,8周龄ApoE基因缺陷小鼠36只随机分为3组:模型组、中药组、舒降之阳性对照组。正常对照组、模型组予0.9%生理盐水灌胃,给药组正常人每kg体重的10倍量灌胃90天后,全自动生化仪测定血清血脂含量,用免疫印记法测定各组肝脏基底膜硫酸乙酰肝素蛋白多糖的表达,用Quantity One 6.0软件进行光密度分析。结果:中药组、阳性对照药组与模型组比较,总胆固醇、低密度脂蛋白水平均明显降低。中药组、阳性对照药组肝脏基底膜HSPG表达与模型组比较明显上调,但与正常对照组比较则明显下调。结论:泽泻萜类化合物对apoE-基因敲除高脂饲料喂养所致动脉粥样硬化小鼠具有降低血清总胆固醇、低密度脂蛋白的作用,对该模型小鼠的肝脏基底膜HSPG表达有调节作用。
基金supported by NIH grants ( P30GM103333,R01AR054385)supported partially by a core access award through NIH NIGMS IDeA Program grant ( P20GM103446)
文摘Perlecan,a heparan sulfate proteoglycan,acts as a mechanical sensor for bone to detect external loading.Deficiency of perlecan increases the risk of osteoporosis in patients with Schwartz-Jampel Syndrome(SJS)and attenuates loading4nduced bone formation in perlecan deficient mice(Hypo).Considering that intracellular calcium[Ca2+]i is an ubiquitous messenger controlling numerous cellular processes including mechanotransduction,we hypothesized that perlecan deficiency impairs bone’s calcium signaling in response to loading.To test this,we performed real-time[Ca2+]i imaging on in situ osteocytes of adult murine tibiae under cyclic loading(8 N,Figure 1).Relative to wild type(WT),Hypo osteocytes showed decreases in the overall[Ca2+]i response rate(-58%),calcium peaks(-33%),cells with multiple peaks(-53%),peak magnitude(-6.8%),and recovery speed to baseline(-23%).RNA sequencing and pathway analysis of tibiae from mice subjected to one or seven days of unilateral loading demonstrated that perlecan deficiency significantly suppressed the calcium signaling,ECM-receptor interaction,and focal adhesion pathways following repetitive loading.Defects in the endoplasmic reticulum(ER)calcium cycling regulators such as Ryr1/ryanodine receptors and Atp2a1/Sercal calcium pumps were identified in Hypo bones.Taken together,impaired calcium signaling may contribute to bone’s reduced anabolic response to loading,underlying the osteoporosis risk for the SJS patients.
文摘Lens fibre differentiation is a life-long process related with lens transparency, and is particularly intense during development, being related with an FGF-2 antero-posterior gradient at the equator level as the main growth factor involved which has been related with the basal membrane of the lens anlagen known as “Lens capsule”. However the lens fibre differentiation induced by FGF2 depends, as in other biological systems, on the local bioavailability of FGF-2 regulated by their relationship with extracellular matrix molecules as Heparan Sulphate Proteoglycans. Here, we try to clarify how Perlecan (a heparan sulphate proteoglycan specific from basement membranes) is involved in lens fibre differentiation at earliest stages of eye development. Our results show that Perlecan, is a major component in the lens capsule during the earliest stages of lens development in chick embryos being present during lens plate induction, lens vesicle stage and the onset of lens fibre differentiation. In order to demonstrate a direct involvement of HSPG-Perlecan in lens fibre differentiation, we generate depleted lenses by HSPG-Perlecan synthesis disruption and specific enzymatic digestion. The HSPG-Perlecan depleted lens show a significant delay or abolition in the lens fibre differentiation which remains in an immature cells displaying DNA synthesis in the posterior epithelium and a decrease in FGF2 lens expression. These data support the hypothesis that lens capsule HSPG-Perlecan is a key molecule involved in lens fibre differentiation during development, probably by involvement in FGF-2 biodisponibility.
