Hearing impairment(HI)affects 1/1000 children and over 2%of the aged population.We have previously reported that mutations in the gene encoding gap junction protein connexin-31(Cx31)are associated with HI.The patholog...Hearing impairment(HI)affects 1/1000 children and over 2%of the aged population.We have previously reported that mutations in the gene encoding gap junction protein connexin-31(Cx31)are associated with HI.The pathological mechanism of the disease mutations remains unknown.Here,we show that expression of Cx31 in the mouse inner ear is developmentally regulated with a high level in adult inner hair cells and spiral ganglion neurons that are critical for the hearing process.In transfected cells,wild type Cx31 protein(Cx31wt)forms functional gap junction at cell-cell-contacts.In contrast,two HIassociated Cx31 mutants,Cx31R180X and Cx31E183K resided primarily in the ER and Golgi-like intracellular punctate structures,respectively,and failed to mediate lucifer yellow transfer.Expression of Cx31 mutants but not Cx31wt leads to upregulation of and increased association with the ER chaperone BiP indicating ER stress induction.Together,the HI-associated Cx31 mutants are impaired in trafficking,promote ER stress,and hence lose the ability to assemble functional gap junctions.The study reveals a potential pathological mechanism of HI-associated Cx31 mutations.展开更多
目的探讨藏雪莲(SSB)多糖是否通过P38丝裂原激活蛋白激酶(P38MAPK)通路减轻中波紫外线(UVB)辐射后皮肤角质形成细胞(Ha Ca T细胞)凋亡引起炎性损伤。方法 2014年10月—2015年3月,提取SSB多糖,体外培养Ha Ca T细胞,将Ha Ca T细胞分为低...目的探讨藏雪莲(SSB)多糖是否通过P38丝裂原激活蛋白激酶(P38MAPK)通路减轻中波紫外线(UVB)辐射后皮肤角质形成细胞(Ha Ca T细胞)凋亡引起炎性损伤。方法 2014年10月—2015年3月,提取SSB多糖,体外培养Ha Ca T细胞,将Ha Ca T细胞分为低剂量辐射组(30 m J/cm2,辐射1 h,A组)和高剂量辐射组(60 m J/cm2,辐射1 h,B组);将A组和B组又分别分为对照组(1组)、辐射组(UVB,2组)、低剂量SSB多糖组(UVB+SSB 10 mg/ml,3组)和高剂量SSB多糖组(UVB+SSB 40 mg/ml,4组)。采用酶联免疫吸附实验(ELISA)法检测并比较白介素6(IL-6)、肿瘤坏死因子α(TNF-α)、P38MAPK、P53、B细胞淋巴瘤因子2(Bcl-2)、Bcl-2相关X(Bax)、半胱氨酸蛋白酶3(Caspase-3)水平。结果 A2组IL-6、TNF-α、P38MAPK、P53、Bax、Caspase-3水平高于A1组,Bcl-2水平低于A1组(P<0.05);A3组IL-6、TNF-α、P38MAPK、Caspase-3水平高于A1组(P<0.05);A4组TNF-α、Bcl-2水平高于A1组(P<0.05);A3组、A4组IL-6、TNF-α、P38MAPK、P53、Bax、Caspase-3水平低于A2组,Bcl-2水平高于A2组(P<0.05);A4组IL-6、TNF-α、Caspase-3水平低于A3组,Bcl-2水平高于A3组(P<0.05)。B2组IL-6、TNF-α、P38MAPK、P53、Bax、Caspase-3水平高于B1组,Bcl-2水平低于B1组(P<0.05);B3组IL-6、TNF-α水平高于B1组,Bcl-2水平低于B1组(P<0.05);B4组IL-6、Bcl-2水平高于B1组,TNF-α、Caspase-3水平低于B1组(P<0.05);B3组、B4组IL-6、TNF-α、P38MAPK、P53、Bax、Caspase-3水平低于B2组,Bcl-2水平高于B2组(P<0.05);B4组IL-6、TNF-α、Caspase-3水平低于B3组,Bcl-2水平高于B3组(P<0.05)。结论 SSB多糖通过P38MAPK通路减少UVB辐射后Ha Ca T细胞凋亡,进而减轻Ha Ca T细胞的炎性损伤。展开更多
目的研究天山雪莲愈伤组织提取物(extract from callus of Saussureainvolucrate,ESI)对人成骨肉瘤细胞MG-63增殖及分化的影响,探讨ESI抗骨质疏松的作用及机制。方法以MG-63为研究对象,采用MTT法和乳酸脱氢酶(LDH)法检测ESI对成骨细胞...目的研究天山雪莲愈伤组织提取物(extract from callus of Saussureainvolucrate,ESI)对人成骨肉瘤细胞MG-63增殖及分化的影响,探讨ESI抗骨质疏松的作用及机制。方法以MG-63为研究对象,采用MTT法和乳酸脱氢酶(LDH)法检测ESI对成骨细胞增殖的影响,相关试剂盒检测碱性磷酸酶(ALP)活性和羟脯氨酸(Hyp)水平,茜素红染色法观察对矿化骨结节形成的影响;实时荧光定量PCR(RT-PCR)检测骨保护素(OPG)和核因子-κB活化因子受体配体(RANKL)基因表达水平;Western blotting法检测OPG/RANKL蛋白水平;检测p38特异性抑制剂SB203580对ESI作用于成骨细胞增殖、分化、矿化以及OPG/RANKL表达的影响。结果 ESI低于125μg/mL对成骨细胞无细胞毒性,31.25、62.5μg/mL对成骨细胞生长有促进作用;ESI显著提高ALP活性、Hyp水平以及矿化骨结节形成;显著上调MG-63细胞OPG mR NA水平,下调RANKLmR NA水平,上调OPG/RANKL蛋白水平;SB203580显著抑制ESI对成骨细胞增殖、ALP活性、矿化结节形成的促进作用以及对胶原蛋白积累量和OPG/RANKL值的提高作用。结论 ESI能够促进成骨细胞增殖、分化和矿化,其机制可能与调节OPG和RANKL基因表达有关,并且可能通过p38丝裂原活化蛋白激酶(MAPK)通路进行信号转导。展开更多
基金supported by grants from the Chinese National Science Foundation(ZZ,KX,DLW)the NIH/NIDCD(ZZ).
文摘Hearing impairment(HI)affects 1/1000 children and over 2%of the aged population.We have previously reported that mutations in the gene encoding gap junction protein connexin-31(Cx31)are associated with HI.The pathological mechanism of the disease mutations remains unknown.Here,we show that expression of Cx31 in the mouse inner ear is developmentally regulated with a high level in adult inner hair cells and spiral ganglion neurons that are critical for the hearing process.In transfected cells,wild type Cx31 protein(Cx31wt)forms functional gap junction at cell-cell-contacts.In contrast,two HIassociated Cx31 mutants,Cx31R180X and Cx31E183K resided primarily in the ER and Golgi-like intracellular punctate structures,respectively,and failed to mediate lucifer yellow transfer.Expression of Cx31 mutants but not Cx31wt leads to upregulation of and increased association with the ER chaperone BiP indicating ER stress induction.Together,the HI-associated Cx31 mutants are impaired in trafficking,promote ER stress,and hence lose the ability to assemble functional gap junctions.The study reveals a potential pathological mechanism of HI-associated Cx31 mutations.
文摘目的探讨藏雪莲(SSB)多糖是否通过P38丝裂原激活蛋白激酶(P38MAPK)通路减轻中波紫外线(UVB)辐射后皮肤角质形成细胞(Ha Ca T细胞)凋亡引起炎性损伤。方法 2014年10月—2015年3月,提取SSB多糖,体外培养Ha Ca T细胞,将Ha Ca T细胞分为低剂量辐射组(30 m J/cm2,辐射1 h,A组)和高剂量辐射组(60 m J/cm2,辐射1 h,B组);将A组和B组又分别分为对照组(1组)、辐射组(UVB,2组)、低剂量SSB多糖组(UVB+SSB 10 mg/ml,3组)和高剂量SSB多糖组(UVB+SSB 40 mg/ml,4组)。采用酶联免疫吸附实验(ELISA)法检测并比较白介素6(IL-6)、肿瘤坏死因子α(TNF-α)、P38MAPK、P53、B细胞淋巴瘤因子2(Bcl-2)、Bcl-2相关X(Bax)、半胱氨酸蛋白酶3(Caspase-3)水平。结果 A2组IL-6、TNF-α、P38MAPK、P53、Bax、Caspase-3水平高于A1组,Bcl-2水平低于A1组(P<0.05);A3组IL-6、TNF-α、P38MAPK、Caspase-3水平高于A1组(P<0.05);A4组TNF-α、Bcl-2水平高于A1组(P<0.05);A3组、A4组IL-6、TNF-α、P38MAPK、P53、Bax、Caspase-3水平低于A2组,Bcl-2水平高于A2组(P<0.05);A4组IL-6、TNF-α、Caspase-3水平低于A3组,Bcl-2水平高于A3组(P<0.05)。B2组IL-6、TNF-α、P38MAPK、P53、Bax、Caspase-3水平高于B1组,Bcl-2水平低于B1组(P<0.05);B3组IL-6、TNF-α水平高于B1组,Bcl-2水平低于B1组(P<0.05);B4组IL-6、Bcl-2水平高于B1组,TNF-α、Caspase-3水平低于B1组(P<0.05);B3组、B4组IL-6、TNF-α、P38MAPK、P53、Bax、Caspase-3水平低于B2组,Bcl-2水平高于B2组(P<0.05);B4组IL-6、TNF-α、Caspase-3水平低于B3组,Bcl-2水平高于B3组(P<0.05)。结论 SSB多糖通过P38MAPK通路减少UVB辐射后Ha Ca T细胞凋亡,进而减轻Ha Ca T细胞的炎性损伤。
