As a critical apoptosis executioner, caspase-3 becomes activated and then enters into the nucleus to exert its function. However, the molecular mechanism of this nuclear entry of active caspase-3 is still unknown. In ...As a critical apoptosis executioner, caspase-3 becomes activated and then enters into the nucleus to exert its function. However, the molecular mechanism of this nuclear entry of active caspase-3 is still unknown. In this study, we revealed that easpase-3 harbors a crm-l-independent nuclear export signal （NES） in its small subunit. Using reversecaspase-3 as the study model, we found that the function of the NES in caspase-3 was not disturbed by the conformational changes during induced caspase-3 activation. Mutations disrupting the cleavage activity or p3-recognition site resulted in a defect in the nuclear entry of active caspase-3. We provide evidence that the p3-mediated specific cleavage activity of active caspase-3 abrogated the function of the NES. In conclusion, our results demonstrate that during caspase-3 activation, NES is constitutively present, p3-mediated specific cleavage activity abrogates the NES function in caspase-3, thus facilitating the nuclear entry of active caspase-3.展开更多
Introduction: The pathogenesis of nasal polyposis and nasal hyperplasia is still unknown. The localization of caspases in nasal polyps and nasal hyperplasia of patients with and without allergic rhinitis was studied. ...Introduction: The pathogenesis of nasal polyposis and nasal hyperplasia is still unknown. The localization of caspases in nasal polyps and nasal hyperplasia of patients with and without allergic rhinitis was studied. Methods: Sections of human nasal polyps (n = 5) and hyperplastic nasal turbinates (5 with, 5 without allergy) were stained for active caspase-3 and caspase-8. Double immunofluorescence was used to evaluate colocalization of the caspases with Ki-M1P and tryptase. TUNEL was performed. Results: Active caspase-3 and caspase-8 were seen in nearly all nasal polyps and hyperplastic nasal turbinates. Active caspase-3 was predominantly localized in stromal cells, identified as mast cells. Caspase-8 was localized in mast cells with the pattern similar to active caspase-3 and additionally found in epithelial cells at the nasal and polyp surface and in epithelial cells of glands. Conclusion: Our results suggest that mast cell apoptosis may be involved in the pathological mechanisms which characterize and sustain chronic inflammatory disorders of the nasal mucosa with and without allergy.展开更多
Objective:To investigate the pyroptosis-inducing effects of celastrol on tumor cells and to explore the potential mechanisms involved,specifically focusing on the role of the caspase-3/gasdermin E(GSDME)signaling path...Objective:To investigate the pyroptosis-inducing effects of celastrol on tumor cells and to explore the potential mechanisms involved,specifically focusing on the role of the caspase-3/gasdermin E(GSDME)signaling pathway and the impact of endoplasmic reticulum(ER)stress and autophagy.Methods: Necrostatin-1(Nec-1),lactate dehydrogenase release(LDH)assay,and Hoechst/propidium iodide(PI)double staining were employed to validate the mode of cell death.Western blot was used to detect the cleavage of GSDME and the expression of light chain 3(LC3)and BIP.Results: Celastrol induced cell swelling with large bubbles,which is consistent with the pyroptotic phenotype.Moreover,treatment with celastrol induced GSDME cleavage,indicating the activation of GSDME-mediated pyroptosis.GSDME knockout via CRISPR/Cas9 blocked the pyroptotic morphology of celastrol in HeLa cells.In addition,cleavage of GSDME was attenuated by a specific caspase-3 inhibitor in celastrol-treated cells,suggesting that GSDME activation was induced by caspase-3.Mechanistically,celastrol induced endoplasmic reticulum(ER)stress and autophagy in HeLa cells,and other ER stress inducers produced effects consistent with those of celastrol.Conclusion: These findings suggest that celastrol triggers caspase-3/GSDME-dependent pyroptosis via activation of ER stress,which may shed light on the potential antitumor clinical applications of celastrol.展开更多
BACKGROUND NLRP3-mediated pyroptosis is recognized as an essential modulator of renal disease pathology.Long noncoding RNAs(lncRNAs)are active participators of diabetic nephropathy(DN).X inactive specific transcript(X...BACKGROUND NLRP3-mediated pyroptosis is recognized as an essential modulator of renal disease pathology.Long noncoding RNAs(lncRNAs)are active participators of diabetic nephropathy(DN).X inactive specific transcript(XIST)expression has been reported to be elevated in the serum of DN patients.AIM To evaluate the mechanism of lncRNA XIST in renal tubular epithelial cell(RTEC)pyroptosis in DN.METHODS A DN rat model was established through streptozotocin injection,and XIST was knocked down by tail vein injection of the lentivirus LV sh-XIST.Renal metabolic and biochemical indices were detected,and pathological changes in the renal tissue were assessed.The expression of indicators related to inflammation and pyroptosis was also detected.High glucose(HG)was used to treat HK2 cells,and cell viability and lactate dehydrogenase(LDH)activity were detected after silencing XIST.The subcellular localization and downstream mechanism of XIST were investigated.Finally,a rescue experiment was carried out to verify that XIST regulates NLR family pyrin domain containing 3(NLRP3)/caspase-1-mediated RTEC pyroptosis through the microRNA-15-5p(miR-15b-5p)/Toll-like receptor 4(TLR4)axis.RESULTS XIST was highly expressed in the DN models.XIST silencing improved renal metabolism and biochemical indices and mitigated renal injury.The expression of inflammation and pyroptosis indicators was significantly increased in DN rats and HG-treated HK2 cells;cell viability was decreased and LDH activity was increased after HGtreatment. Silencing XIST inhibited RTEC pyroptosis by inhibiting NLRP3/caspase-1. Mechanistically,XIST sponged miR-15b-5p to regulate TLR4. Silencing XIST inhibited TLR4 by promotingmiR-15b-5p. miR-15b-5p inhibition or TLR4 overexpression averted the inhibitory effect ofsilencing XIST on HG-induced RTEC pyroptosis.CONCLUSIONSilencing XIST inhibits TLR4 by upregulating miR-15b-5p and ultimately inhibits renal injury inDN by inhibiting NLRP3/caspase-1-mediated RTEC pyroptosis.展开更多
目的探讨三黄连合剂通过NOD样受体蛋白3(NOD-like receptor protein domain associated protein 3,NLRP3)/凋亡相关颗粒样蛋白(apoptosis-associated speck-like protein containing a CARD,ASC)/半胱氨酸天冬氨酸蛋白酶1(cysteine aspa...目的探讨三黄连合剂通过NOD样受体蛋白3(NOD-like receptor protein domain associated protein 3,NLRP3)/凋亡相关颗粒样蛋白(apoptosis-associated speck-like protein containing a CARD,ASC)/半胱氨酸天冬氨酸蛋白酶1(cysteine aspartic acid specific protease-1,Caspase-1)通路对哮喘患儿气道炎症的作用及机制。方法选取2021年1月—2023年10月就诊的90例哮喘患儿,采用数字表法随机分为观察组与对照组,各45例。观察2组哮喘患儿不良反应、1 s用力呼气容积(forced expiratory volume in the first second,FEV_(1)%)、最大呼气流量(peak expiratory flow,PEF)、用力肺活量(forced vital capacity,FVC)、白细胞介素-1β(interleukin-1β,IL-1β)及TNF-α(tumor necrosis factor-α,TNF-α)表达水平差异。结果观察组不良反应发生率为6.66%,对照组为11.11%,差异无统计学意义(P>0.05)。观察组总有效率为95.56%,高于对照组的80.00%(P<0.05)。治疗后FEV_(1)%、PEF、FVC、哮喘控制测试表(asthma control test,ACT)评分高于对照组(P<0.05)。治疗后观察组血清IL-1β、IL-6、IL-8、IL-17、IL-18水平低于对照组(P<0.05)。治疗后观察组患儿血清NLRP3、ASC、Caspase-1、IL-1β蛋白表达水平低于对照组(P<0.05)。结论三黄连合剂治疗能减轻哮喘患儿气道炎症反应,降低炎症因子水平,改善肺功能,减轻病情,提高疗效,其可能通过NLRP3/ASC/Caspase-1通路发挥作用。展开更多
基金Supplementary information is linked to the online version of the paper on the Cell Research website.Acknowledgments We thank Prof Jian Wang （Shanghai University, Shanghai） for his valuable revision and discussion. This work was supported by grants from the National Natural Science Foundation of China （30700411）, Shenzhen Bureau of Science Technology and Information （SZKJ-2006018, SZKJ-2007012）, Shenzhen Nanshan Bureau of Science Technology and Information （2008036） and Shenzhen Key Laboratory Advancement Scheme.
文摘As a critical apoptosis executioner, caspase-3 becomes activated and then enters into the nucleus to exert its function. However, the molecular mechanism of this nuclear entry of active caspase-3 is still unknown. In this study, we revealed that easpase-3 harbors a crm-l-independent nuclear export signal （NES） in its small subunit. Using reversecaspase-3 as the study model, we found that the function of the NES in caspase-3 was not disturbed by the conformational changes during induced caspase-3 activation. Mutations disrupting the cleavage activity or p3-recognition site resulted in a defect in the nuclear entry of active caspase-3. We provide evidence that the p3-mediated specific cleavage activity of active caspase-3 abrogated the function of the NES. In conclusion, our results demonstrate that during caspase-3 activation, NES is constitutively present, p3-mediated specific cleavage activity abrogates the NES function in caspase-3, thus facilitating the nuclear entry of active caspase-3.
文摘Introduction: The pathogenesis of nasal polyposis and nasal hyperplasia is still unknown. The localization of caspases in nasal polyps and nasal hyperplasia of patients with and without allergic rhinitis was studied. Methods: Sections of human nasal polyps (n = 5) and hyperplastic nasal turbinates (5 with, 5 without allergy) were stained for active caspase-3 and caspase-8. Double immunofluorescence was used to evaluate colocalization of the caspases with Ki-M1P and tryptase. TUNEL was performed. Results: Active caspase-3 and caspase-8 were seen in nearly all nasal polyps and hyperplastic nasal turbinates. Active caspase-3 was predominantly localized in stromal cells, identified as mast cells. Caspase-8 was localized in mast cells with the pattern similar to active caspase-3 and additionally found in epithelial cells at the nasal and polyp surface and in epithelial cells of glands. Conclusion: Our results suggest that mast cell apoptosis may be involved in the pathological mechanisms which characterize and sustain chronic inflammatory disorders of the nasal mucosa with and without allergy.
基金supported by grants from startup fund program at Beijing University of Chinese Medicine(90011451310011)key research fund for drug discovery in Chinese medicine at Beijing University of Chinese Medicine(1000061223476)startup fund program at Beijing University of Chinese Medicine(90020361220006).
文摘Objective:To investigate the pyroptosis-inducing effects of celastrol on tumor cells and to explore the potential mechanisms involved,specifically focusing on the role of the caspase-3/gasdermin E(GSDME)signaling pathway and the impact of endoplasmic reticulum(ER)stress and autophagy.Methods: Necrostatin-1(Nec-1),lactate dehydrogenase release(LDH)assay,and Hoechst/propidium iodide(PI)double staining were employed to validate the mode of cell death.Western blot was used to detect the cleavage of GSDME and the expression of light chain 3(LC3)and BIP.Results: Celastrol induced cell swelling with large bubbles,which is consistent with the pyroptotic phenotype.Moreover,treatment with celastrol induced GSDME cleavage,indicating the activation of GSDME-mediated pyroptosis.GSDME knockout via CRISPR/Cas9 blocked the pyroptotic morphology of celastrol in HeLa cells.In addition,cleavage of GSDME was attenuated by a specific caspase-3 inhibitor in celastrol-treated cells,suggesting that GSDME activation was induced by caspase-3.Mechanistically,celastrol induced endoplasmic reticulum(ER)stress and autophagy in HeLa cells,and other ER stress inducers produced effects consistent with those of celastrol.Conclusion: These findings suggest that celastrol triggers caspase-3/GSDME-dependent pyroptosis via activation of ER stress,which may shed light on the potential antitumor clinical applications of celastrol.
基金Supported by Natural Science Foundation of Shenzhen University General Hospital (SUGH2020QD011)
文摘BACKGROUND NLRP3-mediated pyroptosis is recognized as an essential modulator of renal disease pathology.Long noncoding RNAs(lncRNAs)are active participators of diabetic nephropathy(DN).X inactive specific transcript(XIST)expression has been reported to be elevated in the serum of DN patients.AIM To evaluate the mechanism of lncRNA XIST in renal tubular epithelial cell(RTEC)pyroptosis in DN.METHODS A DN rat model was established through streptozotocin injection,and XIST was knocked down by tail vein injection of the lentivirus LV sh-XIST.Renal metabolic and biochemical indices were detected,and pathological changes in the renal tissue were assessed.The expression of indicators related to inflammation and pyroptosis was also detected.High glucose(HG)was used to treat HK2 cells,and cell viability and lactate dehydrogenase(LDH)activity were detected after silencing XIST.The subcellular localization and downstream mechanism of XIST were investigated.Finally,a rescue experiment was carried out to verify that XIST regulates NLR family pyrin domain containing 3(NLRP3)/caspase-1-mediated RTEC pyroptosis through the microRNA-15-5p(miR-15b-5p)/Toll-like receptor 4(TLR4)axis.RESULTS XIST was highly expressed in the DN models.XIST silencing improved renal metabolism and biochemical indices and mitigated renal injury.The expression of inflammation and pyroptosis indicators was significantly increased in DN rats and HG-treated HK2 cells;cell viability was decreased and LDH activity was increased after HGtreatment. Silencing XIST inhibited RTEC pyroptosis by inhibiting NLRP3/caspase-1. Mechanistically,XIST sponged miR-15b-5p to regulate TLR4. Silencing XIST inhibited TLR4 by promotingmiR-15b-5p. miR-15b-5p inhibition or TLR4 overexpression averted the inhibitory effect ofsilencing XIST on HG-induced RTEC pyroptosis.CONCLUSIONSilencing XIST inhibits TLR4 by upregulating miR-15b-5p and ultimately inhibits renal injury inDN by inhibiting NLRP3/caspase-1-mediated RTEC pyroptosis.
文摘目的探讨三黄连合剂通过NOD样受体蛋白3(NOD-like receptor protein domain associated protein 3,NLRP3)/凋亡相关颗粒样蛋白(apoptosis-associated speck-like protein containing a CARD,ASC)/半胱氨酸天冬氨酸蛋白酶1(cysteine aspartic acid specific protease-1,Caspase-1)通路对哮喘患儿气道炎症的作用及机制。方法选取2021年1月—2023年10月就诊的90例哮喘患儿,采用数字表法随机分为观察组与对照组,各45例。观察2组哮喘患儿不良反应、1 s用力呼气容积(forced expiratory volume in the first second,FEV_(1)%)、最大呼气流量(peak expiratory flow,PEF)、用力肺活量(forced vital capacity,FVC)、白细胞介素-1β(interleukin-1β,IL-1β)及TNF-α(tumor necrosis factor-α,TNF-α)表达水平差异。结果观察组不良反应发生率为6.66%,对照组为11.11%,差异无统计学意义(P>0.05)。观察组总有效率为95.56%,高于对照组的80.00%(P<0.05)。治疗后FEV_(1)%、PEF、FVC、哮喘控制测试表(asthma control test,ACT)评分高于对照组(P<0.05)。治疗后观察组血清IL-1β、IL-6、IL-8、IL-17、IL-18水平低于对照组(P<0.05)。治疗后观察组患儿血清NLRP3、ASC、Caspase-1、IL-1β蛋白表达水平低于对照组(P<0.05)。结论三黄连合剂治疗能减轻哮喘患儿气道炎症反应,降低炎症因子水平,改善肺功能,减轻病情,提高疗效,其可能通过NLRP3/ASC/Caspase-1通路发挥作用。
