Background:Oleanolic acid(OA),a pentacyclic triterpenoid exhibiting specific anti-cancer properties and highly effective antioxidant activity,was isolated from traditional Chinese medicinal herbs.Conversely,the OA that...Background:Oleanolic acid(OA),a pentacyclic triterpenoid exhibiting specific anti-cancer properties and highly effective antioxidant activity,was isolated from traditional Chinese medicinal herbs.Conversely,the OA that impacts colon cancer(CC)cells and its underlying mechanisms remain poorly understood.Methods:The cytotoxic effect of OA alone or OA-5-Fluorouracil(5-FU)combination on normal and CC cells was analyzed by methyl thiazolyl diphenyl-tetrazolium bromide(MTT).Then,the impact of OA on CC cell lines(LoVo and HT-29)proliferation and stemness were measured using colon formation and tumorsphere formation assays.Octamer-binding transcription factor 4(Oct4),Prominin-1(CD133),Nanog,and transcription factor SOX-2(SOX2)are cell stemness-related indicators whose expression was assessed usingfluorescence qPCR assay,Western blotting,and immunohistochemistry.The effect of OA on the proliferative potency of CC cells was evaluated using an in vivo model.Results:The stem-like characteristics and clone production of colon cancer cells were markedly reduced by OA alone or in combination with OA-5-FU.Moreover,OA increases the susceptibility of CC cells to 5-FU by blocking the cell stemness-related markers(CD133,Nanog,SOX2,and Oct4)expression levels both in vitro and in vivo,as well as by inactivating the activator of transcription 3(STAT3 signaling)and Janus kinase 2/signal transducer(JAK2).Conclusion:Thesefindings imply that oleanolic acid,both in vitro and in vivo,suppresses the JAK2/STAT3 pathway,which in turn reverses chemoresistance and decreases colon cancer cell stemness.Therefore,by reducing the recommended amount of 5-FU,this strategy may improve chemotherapeutic effectiveness and minimize undesired side effects.展开更多
目的 探讨高迁移率族蛋白B1(high mobility group protein B1,HMGB1)加重神经性疼痛的作用机制。方法 在脂多糖(lipopolysaccharide, LPS)激活的BV-2细胞中干扰HMGB1表达,检测细胞凋亡、炎症因子分泌,以及JAK2和STAT3蛋白的磷酸化水平...目的 探讨高迁移率族蛋白B1(high mobility group protein B1,HMGB1)加重神经性疼痛的作用机制。方法 在脂多糖(lipopolysaccharide, LPS)激活的BV-2细胞中干扰HMGB1表达,检测细胞凋亡、炎症因子分泌,以及JAK2和STAT3蛋白的磷酸化水平。检测LPS激活的BV-2细胞中JAK2和STAT3蛋白的磷酸化水平,并引入JAK2抑制剂探究JAK2/STAT3轴阻断对细胞的影响。建立HMGB1敲低的脊神经结扎(spinal nerve ligation, SNL)大鼠模型,检测脊髓组织中通路蛋白表达和炎症因子分泌,评估SNL大鼠的机械痛敏阈值和热痛敏阈值。结果 LPS处理的BV-2细胞中HMGB1表达上调,干扰HMGB1表达显著抑制细胞凋亡和炎症反应。LPS处理激活JAK2/STAT3轴,且JAK2/STAT3轴激活是由HMGB1表达上调介导的。在SNL大鼠模型中,脊髓组织中HMGB1和通路蛋白表达增加,炎症反应加重,机械痛敏阈值和热痛敏阈值均降低。通过敲低HMGB1表达,观察到HMGB1和通路蛋白的表达下调,炎症减轻,神经性疼痛缓解。结论 HMGB1通过激活JAK2/STAT3轴加重神经性疼痛。展开更多
基金The work was supported by grants from the Scientific Research Projects of Medical and Health Institutions of Longhua District,Shenzhen(2021016)Shenzhen Basic Research Project(JCYJ20210324125803008).
文摘Background:Oleanolic acid(OA),a pentacyclic triterpenoid exhibiting specific anti-cancer properties and highly effective antioxidant activity,was isolated from traditional Chinese medicinal herbs.Conversely,the OA that impacts colon cancer(CC)cells and its underlying mechanisms remain poorly understood.Methods:The cytotoxic effect of OA alone or OA-5-Fluorouracil(5-FU)combination on normal and CC cells was analyzed by methyl thiazolyl diphenyl-tetrazolium bromide(MTT).Then,the impact of OA on CC cell lines(LoVo and HT-29)proliferation and stemness were measured using colon formation and tumorsphere formation assays.Octamer-binding transcription factor 4(Oct4),Prominin-1(CD133),Nanog,and transcription factor SOX-2(SOX2)are cell stemness-related indicators whose expression was assessed usingfluorescence qPCR assay,Western blotting,and immunohistochemistry.The effect of OA on the proliferative potency of CC cells was evaluated using an in vivo model.Results:The stem-like characteristics and clone production of colon cancer cells were markedly reduced by OA alone or in combination with OA-5-FU.Moreover,OA increases the susceptibility of CC cells to 5-FU by blocking the cell stemness-related markers(CD133,Nanog,SOX2,and Oct4)expression levels both in vitro and in vivo,as well as by inactivating the activator of transcription 3(STAT3 signaling)and Janus kinase 2/signal transducer(JAK2).Conclusion:Thesefindings imply that oleanolic acid,both in vitro and in vivo,suppresses the JAK2/STAT3 pathway,which in turn reverses chemoresistance and decreases colon cancer cell stemness.Therefore,by reducing the recommended amount of 5-FU,this strategy may improve chemotherapeutic effectiveness and minimize undesired side effects.
