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
Src homology 2 domain-containing tyrosine phosphatase 2(SHP2)is an essential tyrosine phosphatase that is pivotal in regulating various cellular signaling pathways such as cell growth,differentiation,and survival.The ...Src homology 2 domain-containing tyrosine phosphatase 2(SHP2)is an essential tyrosine phosphatase that is pivotal in regulating various cellular signaling pathways such as cell growth,differentiation,and survival.The activation of SHP2 has been shown to have a therapeutic effect in colitis and Parkinson's disease.Thus,the identification of SHP2 activators and a complete understanding of their mechanism is required.We used a two-step screening assay to determine a novel allosteric activator of SHP2 that stabilizes it in an open conformation.Oleanolic acid was identified as a suitable candidate.By binding to R362,K364,and K366 in the active center of the PTP domain,oleanolic acid maintained the active open state of SHP2,which facilitated the binding between SHP2 and its substrate.This oleanolic acid-activated SHP2 hindered Th17 differentiation by disturbing the interaction between STAT3 and IL-6Rαand inhibiting the activation of STAT3.Furthermore,via the activation of SHP2 and subsequent attenuation of the STAT3-Th17 axis,oleanolic acid effectively mitigated colitis in mice.This protective effect was abrogated by SHP2 knockout or administration of the SHP2 inhibitor SHP099.These findings underscore the potential of oleanolic acid as a promising therapeutic agent for treating inflammatory bowel diseases.展开更多
从穗序鹅掌柴(Schettlera Delavayi Haums ex Diels,五加科)中分得7个单体化合物,经化学方法和光谱分析鉴定其中3个化合物的结构为:齐墩果酸-3-O-α-L-吡喃阿拉伯糖甙(Oleanolisacid-3-O-a-L-arabinopyranoside,S_0),齐墩果酸(Oleanolic...从穗序鹅掌柴(Schettlera Delavayi Haums ex Diels,五加科)中分得7个单体化合物,经化学方法和光谱分析鉴定其中3个化合物的结构为:齐墩果酸-3-O-α-L-吡喃阿拉伯糖甙(Oleanolisacid-3-O-a-L-arabinopyranoside,S_0),齐墩果酸(Oleanolic acid,G),齐墩果酮酸(Oleanonicacid,F)。这几种化合物均为首次从该植物中分得。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.
基金supported by the National Natural Science Foundation of China(82173820,82073856,82273933)Fundamental Research Funds for the Central Universities(020814380160,China)+1 种基金Innovation Team and Talents Cultivation Program of National Administration of Traditional Chinese Medicine(ZYYCXTD-C-202208,China)the Young Scholar Foundation from Cyrus Tang Foundation(China).
文摘Src homology 2 domain-containing tyrosine phosphatase 2(SHP2)is an essential tyrosine phosphatase that is pivotal in regulating various cellular signaling pathways such as cell growth,differentiation,and survival.The activation of SHP2 has been shown to have a therapeutic effect in colitis and Parkinson's disease.Thus,the identification of SHP2 activators and a complete understanding of their mechanism is required.We used a two-step screening assay to determine a novel allosteric activator of SHP2 that stabilizes it in an open conformation.Oleanolic acid was identified as a suitable candidate.By binding to R362,K364,and K366 in the active center of the PTP domain,oleanolic acid maintained the active open state of SHP2,which facilitated the binding between SHP2 and its substrate.This oleanolic acid-activated SHP2 hindered Th17 differentiation by disturbing the interaction between STAT3 and IL-6Rαand inhibiting the activation of STAT3.Furthermore,via the activation of SHP2 and subsequent attenuation of the STAT3-Th17 axis,oleanolic acid effectively mitigated colitis in mice.This protective effect was abrogated by SHP2 knockout or administration of the SHP2 inhibitor SHP099.These findings underscore the potential of oleanolic acid as a promising therapeutic agent for treating inflammatory bowel diseases.
