目的探讨γ-分泌酶抑制剂DAPT对马兜铃酸(AA)诱导引起肾小管上皮细胞表型转化与胶原累积的作用及分子机制。方法将体外培养的大鼠肾小管上皮细胞NRK-52E分为正常细胞对照组、AA10 mg·L-1组、AA 10 mg·L-1+DAPT1和10μmol·...目的探讨γ-分泌酶抑制剂DAPT对马兜铃酸(AA)诱导引起肾小管上皮细胞表型转化与胶原累积的作用及分子机制。方法将体外培养的大鼠肾小管上皮细胞NRK-52E分为正常细胞对照组、AA10 mg·L-1组、AA 10 mg·L-1+DAPT1和10μmol·L-1组。24 h后,实时荧光定量PCR检测Notch信号关键分子Notch1、Jagged1和Numb、表型转化相关分子转化生长因子β1(TGF-β1)、E-钙黏着蛋白、α-平滑肌肌动蛋白(α-SMA)、骨形态发生蛋白7(Bmp7)和基质成分Ⅰ型胶原a1(Col1a1)和Ⅲ型胶原a1(Col3a1)m RNA的表达;细胞免疫荧光染色法检测Notch1、Jagged1、α-SMA和Col3a1蛋白的表达。结果与正常细胞对照相比,AA处理后,肾小管上皮细胞基质相关因子TGF-β1,α-SMA和Col3a1 m RNA表达上调,上皮标志物E-钙黏着蛋白m RNA的表达受到抑制,而且导致了Notch1、Jagged1 m RNA表达的上调和Numb m RNA表达的下调(P<0.05),提示AA促进肾小管上皮细胞表型转化与基质累积,同时激活了Notch信号通路。DAPT干预AA作用后,Notch1(P<0.01)和Jagged1(P<0.05)的m RNA表达下调,Numb m RNA表达上调(P<0.05),说明DAPT抑制了AA诱导的Notch信号通路活化。此外,与AA损伤组相比,DAPT也降低了TGF-β1,α-SMA,Col1a1和Col3a1 m RNA表达(P<0.05),提高BMP-7和E-钙黏着蛋白m RNA表达(P<0.05),提示DAPT抑制了AA诱导的上皮细胞的表型转化与基质累积。结论 DAPT抑制AA诱导的肾小管上皮细胞的表型转化与基质累积,其可能机制是DAPT靶向干预Notch信号的活化。展开更多
Atoh1 overexpression in cochlear epithelium induces new hair cell formation. Use of adenovirus-mediated Atoh1 overexpression has mainly focused on the rat lesser epithelial ridge and induces ectopic hair cell regenera...Atoh1 overexpression in cochlear epithelium induces new hair cell formation. Use of adenovirus-mediated Atoh1 overexpression has mainly focused on the rat lesser epithelial ridge and induces ectopic hair cell regeneration. The sensory region of rat cochlea is difficult to transfect, thus new hair cells are rarely produced in situ in rat cochlear explants. After culturing rat cochleae in medium containing 10% fetal bovine serum, adenovirus successfully infected the sensory region as the width of the supporting cell area was significantly increased. Adenovirus encoding Atoh1 infected the sensory region and induced hair cell formation in situ. Combined application of the Notch inhibitor DAPT and Atoh1 increased the Atoh1 expression level and decreased hes1 and hes5 levels, further promoting hair cell generation. Our results demonstrate that DAPT enhances Atoh1 activity to promote hair cell regeneration in rat cochlear sensory epithelium in vitro.展开更多
文摘目的探讨γ-分泌酶抑制剂DAPT对马兜铃酸(AA)诱导引起肾小管上皮细胞表型转化与胶原累积的作用及分子机制。方法将体外培养的大鼠肾小管上皮细胞NRK-52E分为正常细胞对照组、AA10 mg·L-1组、AA 10 mg·L-1+DAPT1和10μmol·L-1组。24 h后,实时荧光定量PCR检测Notch信号关键分子Notch1、Jagged1和Numb、表型转化相关分子转化生长因子β1(TGF-β1)、E-钙黏着蛋白、α-平滑肌肌动蛋白(α-SMA)、骨形态发生蛋白7(Bmp7)和基质成分Ⅰ型胶原a1(Col1a1)和Ⅲ型胶原a1(Col3a1)m RNA的表达;细胞免疫荧光染色法检测Notch1、Jagged1、α-SMA和Col3a1蛋白的表达。结果与正常细胞对照相比,AA处理后,肾小管上皮细胞基质相关因子TGF-β1,α-SMA和Col3a1 m RNA表达上调,上皮标志物E-钙黏着蛋白m RNA的表达受到抑制,而且导致了Notch1、Jagged1 m RNA表达的上调和Numb m RNA表达的下调(P<0.05),提示AA促进肾小管上皮细胞表型转化与基质累积,同时激活了Notch信号通路。DAPT干预AA作用后,Notch1(P<0.01)和Jagged1(P<0.05)的m RNA表达下调,Numb m RNA表达上调(P<0.05),说明DAPT抑制了AA诱导的Notch信号通路活化。此外,与AA损伤组相比,DAPT也降低了TGF-β1,α-SMA,Col1a1和Col3a1 m RNA表达(P<0.05),提高BMP-7和E-钙黏着蛋白m RNA表达(P<0.05),提示DAPT抑制了AA诱导的上皮细胞的表型转化与基质累积。结论 DAPT抑制AA诱导的肾小管上皮细胞的表型转化与基质累积,其可能机制是DAPT靶向干预Notch信号的活化。
基金supported by the National Natural Science Foundation of China,No.81420108010,81271084,81200740,81371093
文摘Atoh1 overexpression in cochlear epithelium induces new hair cell formation. Use of adenovirus-mediated Atoh1 overexpression has mainly focused on the rat lesser epithelial ridge and induces ectopic hair cell regeneration. The sensory region of rat cochlea is difficult to transfect, thus new hair cells are rarely produced in situ in rat cochlear explants. After culturing rat cochleae in medium containing 10% fetal bovine serum, adenovirus successfully infected the sensory region as the width of the supporting cell area was significantly increased. Adenovirus encoding Atoh1 infected the sensory region and induced hair cell formation in situ. Combined application of the Notch inhibitor DAPT and Atoh1 increased the Atoh1 expression level and decreased hes1 and hes5 levels, further promoting hair cell generation. Our results demonstrate that DAPT enhances Atoh1 activity to promote hair cell regeneration in rat cochlear sensory epithelium in vitro.
