Ras homolog enriched in brain(Rheb) is a small GTPase that activates mammalian target of rapamycin complex 1(mTORC1).Previous studies have shown that constitutively active Rheb can enhance the regeneration of sensory ...Ras homolog enriched in brain(Rheb) is a small GTPase that activates mammalian target of rapamycin complex 1(mTORC1).Previous studies have shown that constitutively active Rheb can enhance the regeneration of sensory axons after spinal cord injury by activating downstream effectors of mTOR.S6K1 and4E-BP1 are important downstream effectors of mTORC1.In this study,we investigated the role of Rheb/mTOR and its downstream effectors S6K1 and 4E-BP1in the protection of retinal ganglion cells.We transfected an optic nerve crush mouse model with adeno-associated viral 2-mediated constitutively active Rheb and observed the effects on retinal ganglion cell survival and axon regeneration.We found that overexpression of constitutively active Rheb promoted survival of retinal ganglion cells in the acute(14 days) and chronic(21 and 42 days) stages of injury.We also found that either co-expression of the dominant-negative S6K1mutant or the constitutively active 4E-BP1 mutant together with constitutively active Rheb markedly inhibited axon regeneration of retinal ganglion cells.This suggests that mTORC1-mediated S6K1 activation and 4E-BP1 inhibition were necessary components for constitutively active Rheb-induced axon regeneration.However,only S6K1 activation,but not 4E-BP1 knockdown,induced axon regeneration when applied alone.Furthermore,S6K1 activation promoted the survival of retinal ganglion cells at 14 days post-injury,whereas 4E-BP1 knockdown unexpectedly slightly decreased the survival of retinal ganglion cells at 14 days postinjury.Ove rexpression of constitutively active 4E-BP1 increased the survival of retinal ganglion cells at 14 days post-injury.Likewise,co-expressing constitutively active Rheb and constitutively active 4E-BP1 markedly increased the survival of retinal ganglion cells compared with overexpression of constitutively active Rheb alone at 14 days post-injury.These findings indicate that functional 4E-BP1 and S6K1 are neuroprotective and that 4E-BP1 may exert protective effects through a pathway at least partially independent of Rhe b/mTOR.Together,our results show that constitutively active Rheb promotes the survival of retinal ganglion cells and axon regeneration through modulating S6K1 and 4E-BP1 activity.Phosphorylated S6K1 and 4E-BP1 promote axon regeneration but play an antagonistic role in the survival of retinal ganglion cells.展开更多
The regulating effects of TCM treatments including clearing away heat and toxic materials,promoting blood circulation and removing blood stasis,and strengthening the spleen and regulating qi on the oncogene transcript...The regulating effects of TCM treatments including clearing away heat and toxic materials,promoting blood circulation and removing blood stasis,and strengthening the spleen and regulating qi on the oncogene transcription were observed in the liver cancer model rats.The preliminary results indicated that the mRNA levels of H-ras N-ras and K-ras,and signal molecules correlated with the ras/MAPK signal transduction pathway were down-regulated by the different TCM treatments in varying degrees.Also,the regulating effects of the treatments on differently-displayed genes were discrepant.It is suggested that the molecular mechanisms of the TCM treatments for liver cancer was complex with different target genes.展开更多
BACKGROUND Alzheimer’s disease(AD)is a neurodegenerative condition characterized by oxidative stress and neuroinflammation.Tanshinone ⅡA(Tan-ⅡA),a bioactive compound isolated from Salvia miltiorrhiza plants,has sho...BACKGROUND Alzheimer’s disease(AD)is a neurodegenerative condition characterized by oxidative stress and neuroinflammation.Tanshinone ⅡA(Tan-ⅡA),a bioactive compound isolated from Salvia miltiorrhiza plants,has shown potential neuroprotective effects;however,the mechanisms underlying such a function remain unclear.AIM To investigate potential Tan-ⅡA neuroprotective effects in AD and to elucidate their underlying mechanisms.METHODS Hematoxylin and eosin staining was utilized to analyze structural brain tissue morphology.To assess changes in oxidative stress and neuroinflammation,we performed enzyme-linked immunosorbent assay and western blotting.Additionally,the effect of Tan-ⅡA on AD cell models was evaluated in vitro using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.Genetic changes related to the long non-coding RNA(lncRNA)nuclear-enriched abundant transcript 1(NEAT1)/microRNA(miRNA,miR)-291a-3p/member RAS oncogene family Rab22a axis were assessed through reverse transcription quantitative polymerase chain reaction.RESULTS In vivo,Tan-ⅡA treatment improved neuronal morphology and attenuated oxidative stress and neuroinflammation in the brain tissue of AD mice.In vitro experiments showed that Tan-ⅡA dose-dependently ameliorated the amyloid-beta 1-42-induced reduction of neural stem cell viability,apoptosis,oxidative stress,and neuroinflammation.In this process,the lncRNA NEAT1-a potential therapeutic target-is highly expressed in AD mice and downregulated via Tan-ⅡA treatment.Mechanistically,NEAT1 promotes the transcription and translation of Rab22a via miR-291a-3p,which activates nuclear factor kappa-B(NF-κB)signaling,leading to activation of the pro-apoptotic B-cell lymphoma 2-associated X protein and inhibition of the anti-apoptotic B-cell lymphoma 2 protein,which exacerbates AD.Tan-ⅡA intervention effectively blocked this process by inhibiting the NEAT1/miR-291a-3p/Rab22a axis and NF-κB signaling.CONCLUSION This study demonstrates that Tan-ⅡA exerts neuroprotective effects in AD by modulating the NEAT1/miR-291a-3p/Rab22a/NF-κB signaling pathway,serving as a foundation for the development of innovative approaches for AD therapy.展开更多
Abnormal activation of the Ras/Raf/Mek/Erk signaling cascade plays an important role in glioma. Inhibition of this aberrant activity could effectively hinder glioma cell proliferation and promote cell apoptosis. To in...Abnormal activation of the Ras/Raf/Mek/Erk signaling cascade plays an important role in glioma. Inhibition of this aberrant activity could effectively hinder glioma cell proliferation and promote cell apoptosis. To investigate the mechanism of gJioblastoma treatment by neural stem ceiJ trans- plantation with respect to the Ras/Raf/Mek/Erk pathway, C6 glioma cells were prepared in sus- pension and then infused into the rat brain to establish a glioblastoma model. Neural stem cells isolated from fetal rats were then injected into the brain of this glioblastoma model. Results showed that Raf-1, Erk and Bcl-2 protein expression significantly increased, while Caspase-3 protein expression decreased. After transplantation of neural stem cells, Raf-1, Erk and Bcl-2 protein expression significantly decreased, while Caspase-3 protein expression significantly in-creased. Our findings indicate that transplantation of neural stem cells may promote apoptosis of glioma cells by inhibiting Ras/Raf/Mek/Erk signaling, and thus may represent a novel treatment approach for glioblastoma.展开更多
The biogeochemical processes of marine sediments are influenced by bioturbation and organic carbon decomposition,which is crucial for understanding global element cycles and climate change.Two sediment cores were acqu...The biogeochemical processes of marine sediments are influenced by bioturbation and organic carbon decomposition,which is crucial for understanding global element cycles and climate change.Two sediment cores were acquired in 2017 from abyssal basins in the central-eastern tropical Pacific to determine the bioturbation and organic carbon degradation processes.The radioactivity concentrations of 210Pb and 226Ra in the sediment cores were measured,indicating the presence of significant excess 210Pb(210Pbex)signals in the sediment cores.Besides,a manganese nodule was discovered in one core,which had a substantial influence on the distribution of 210Pbex.With the exception of this anomalous finding,the bioturbation coefficients in the remaining core were estimated to be 10.6 cm^(2)/a using a steady-state diffusion model,greater than most of the deep-sea sediments from the equatorial eastern Pacific.By using a bio-diffusion model,we further calculated the degradation rates of organic carbon(8.02 ka-1),which is also higher than other areas of the Pacific.Our findings displayed the presence of a biologically active benthic ecosystem in the central-eastern tropical Pacific.展开更多
Genome sequencing has revealed frequent mutations in Ras homolog family member A(RHOA)among various cancers with unique aberrant profiles and pathogenic effects,especially in peripheral T-cell lymphoma(PTCL).The discr...Genome sequencing has revealed frequent mutations in Ras homolog family member A(RHOA)among various cancers with unique aberrant profiles and pathogenic effects,especially in peripheral T-cell lymphoma(PTCL).The discrete positional distribution and types of RHOA amino acid substitutions vary according to the tumor type,thereby leading to different functional and biological properties,which provide new insight into the molecular pathogenesis and potential targeted therapies for various tumors.However,the similarities and discrepancies in characteristics of RHOA mutations among various histologic subtypes of PTCL have not been fully elucidated.Herein we highlight the inconsistencies and complexities of the type and location of RHOA mutations and demonstrate the contribution of RHOA variants to the pathogenesis of PTCL by combining epigenetic abnormalities and activating multiple downstream pathways.The promising potential of targeting RHOA as a therapeutic modality is also outlined.This review provides new insight in the field of personalized medicine to improve the clinical outcomes for patients.展开更多
[Objectives]To investigate the anti-inflammatory effect of Embelia parviflora Wall.polysaccharide on rheumatoid arthritis(RA)in rats.[Methods]RA rat model was induced by type II collagen.After successful modeling,the ...[Objectives]To investigate the anti-inflammatory effect of Embelia parviflora Wall.polysaccharide on rheumatoid arthritis(RA)in rats.[Methods]RA rat model was induced by type II collagen.After successful modeling,the rats were divided into model group,positive group,low,medium and high dose of E.parviflora Wall.polysaccharide groups,and normal control group.Body mass,toe volume and arthritis index were measured,and thymus index and spleen index were calculated.The levels of interleukin-1β,interleukin-6 and tumor necrosis factor-αin serum and synovial tissue of ankle joint were detected by ELISA.[Results]Compared with the normal control group,the pathological changes such as synovial hyperplasia and unclear layer were observed in the model group,the body mass was decreased(P<0.05),the toe volume,arthritis index,thymus and spleen index were increased(P<0.05),and the levels of IL-1β,IL-6 and TNF-αin serum and ankle synovial tissue were increased(P<0.05).Compared with the model group,the histopathological changes in synovium of ankle joint in the positive group and the medium and high dose groups of E.parviflora Wall.polysaccharide were significantly improved,and the body mass was increased(P<0.05).The toe volume,arthritis index,thymus index and spleen index were decreased(P<0.05).The levels of IL-Iβ,IL-6 and TNF-αin serum and synovial tissue of ankle joint were increased(P<0.05),while there was no significant difference between the low dose group of E.parviflora Wall.polysaccharide and the model group(P>0.05).[Conclusions]E.parviflora Wall.polysaccharide can reduce the body's inflammatory response and improve RA,which may be related to the inhibition of the activation of inflammatory cytokines IL-1β,IL-6 and TNF-α.展开更多
基金National Natural Science Foundation of China,Nos.82070967,81770930the Natural Science Foundation of Hunan Province,No.2020jj4788 (all to BJ)。
文摘Ras homolog enriched in brain(Rheb) is a small GTPase that activates mammalian target of rapamycin complex 1(mTORC1).Previous studies have shown that constitutively active Rheb can enhance the regeneration of sensory axons after spinal cord injury by activating downstream effectors of mTOR.S6K1 and4E-BP1 are important downstream effectors of mTORC1.In this study,we investigated the role of Rheb/mTOR and its downstream effectors S6K1 and 4E-BP1in the protection of retinal ganglion cells.We transfected an optic nerve crush mouse model with adeno-associated viral 2-mediated constitutively active Rheb and observed the effects on retinal ganglion cell survival and axon regeneration.We found that overexpression of constitutively active Rheb promoted survival of retinal ganglion cells in the acute(14 days) and chronic(21 and 42 days) stages of injury.We also found that either co-expression of the dominant-negative S6K1mutant or the constitutively active 4E-BP1 mutant together with constitutively active Rheb markedly inhibited axon regeneration of retinal ganglion cells.This suggests that mTORC1-mediated S6K1 activation and 4E-BP1 inhibition were necessary components for constitutively active Rheb-induced axon regeneration.However,only S6K1 activation,but not 4E-BP1 knockdown,induced axon regeneration when applied alone.Furthermore,S6K1 activation promoted the survival of retinal ganglion cells at 14 days post-injury,whereas 4E-BP1 knockdown unexpectedly slightly decreased the survival of retinal ganglion cells at 14 days postinjury.Ove rexpression of constitutively active 4E-BP1 increased the survival of retinal ganglion cells at 14 days post-injury.Likewise,co-expressing constitutively active Rheb and constitutively active 4E-BP1 markedly increased the survival of retinal ganglion cells compared with overexpression of constitutively active Rheb alone at 14 days post-injury.These findings indicate that functional 4E-BP1 and S6K1 are neuroprotective and that 4E-BP1 may exert protective effects through a pathway at least partially independent of Rhe b/mTOR.Together,our results show that constitutively active Rheb promotes the survival of retinal ganglion cells and axon regeneration through modulating S6K1 and 4E-BP1 activity.Phosphorylated S6K1 and 4E-BP1 promote axon regeneration but play an antagonistic role in the survival of retinal ganglion cells.
文摘The regulating effects of TCM treatments including clearing away heat and toxic materials,promoting blood circulation and removing blood stasis,and strengthening the spleen and regulating qi on the oncogene transcription were observed in the liver cancer model rats.The preliminary results indicated that the mRNA levels of H-ras N-ras and K-ras,and signal molecules correlated with the ras/MAPK signal transduction pathway were down-regulated by the different TCM treatments in varying degrees.Also,the regulating effects of the treatments on differently-displayed genes were discrepant.It is suggested that the molecular mechanisms of the TCM treatments for liver cancer was complex with different target genes.
基金Supported by 2020 Guangxi Zhuang Autonomous Region Health Care Commission Self-Financing Research Projects,No.Z202000962023 Guangxi University Young and Middle-Aged Teachers’Basic Research Ability Improvement Project,No.2023KY0091+1 种基金National Natural Science Foundation of China,No.82260241the Natural Science Foundation of Guangxi Province,No.2015GXNSFAA139171 and No.2020GXNSFAA259053.
文摘BACKGROUND Alzheimer’s disease(AD)is a neurodegenerative condition characterized by oxidative stress and neuroinflammation.Tanshinone ⅡA(Tan-ⅡA),a bioactive compound isolated from Salvia miltiorrhiza plants,has shown potential neuroprotective effects;however,the mechanisms underlying such a function remain unclear.AIM To investigate potential Tan-ⅡA neuroprotective effects in AD and to elucidate their underlying mechanisms.METHODS Hematoxylin and eosin staining was utilized to analyze structural brain tissue morphology.To assess changes in oxidative stress and neuroinflammation,we performed enzyme-linked immunosorbent assay and western blotting.Additionally,the effect of Tan-ⅡA on AD cell models was evaluated in vitro using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.Genetic changes related to the long non-coding RNA(lncRNA)nuclear-enriched abundant transcript 1(NEAT1)/microRNA(miRNA,miR)-291a-3p/member RAS oncogene family Rab22a axis were assessed through reverse transcription quantitative polymerase chain reaction.RESULTS In vivo,Tan-ⅡA treatment improved neuronal morphology and attenuated oxidative stress and neuroinflammation in the brain tissue of AD mice.In vitro experiments showed that Tan-ⅡA dose-dependently ameliorated the amyloid-beta 1-42-induced reduction of neural stem cell viability,apoptosis,oxidative stress,and neuroinflammation.In this process,the lncRNA NEAT1-a potential therapeutic target-is highly expressed in AD mice and downregulated via Tan-ⅡA treatment.Mechanistically,NEAT1 promotes the transcription and translation of Rab22a via miR-291a-3p,which activates nuclear factor kappa-B(NF-κB)signaling,leading to activation of the pro-apoptotic B-cell lymphoma 2-associated X protein and inhibition of the anti-apoptotic B-cell lymphoma 2 protein,which exacerbates AD.Tan-ⅡA intervention effectively blocked this process by inhibiting the NEAT1/miR-291a-3p/Rab22a axis and NF-κB signaling.CONCLUSION This study demonstrates that Tan-ⅡA exerts neuroprotective effects in AD by modulating the NEAT1/miR-291a-3p/Rab22a/NF-κB signaling pathway,serving as a foundation for the development of innovative approaches for AD therapy.
文摘Abnormal activation of the Ras/Raf/Mek/Erk signaling cascade plays an important role in glioma. Inhibition of this aberrant activity could effectively hinder glioma cell proliferation and promote cell apoptosis. To investigate the mechanism of gJioblastoma treatment by neural stem ceiJ trans- plantation with respect to the Ras/Raf/Mek/Erk pathway, C6 glioma cells were prepared in sus- pension and then infused into the rat brain to establish a glioblastoma model. Neural stem cells isolated from fetal rats were then injected into the brain of this glioblastoma model. Results showed that Raf-1, Erk and Bcl-2 protein expression significantly increased, while Caspase-3 protein expression decreased. After transplantation of neural stem cells, Raf-1, Erk and Bcl-2 protein expression significantly decreased, while Caspase-3 protein expression significantly in-creased. Our findings indicate that transplantation of neural stem cells may promote apoptosis of glioma cells by inhibiting Ras/Raf/Mek/Erk signaling, and thus may represent a novel treatment approach for glioblastoma.
基金The Scientific Research Foundation of Third Institute of Oceanography,Ministry of Natural Resources under contract No.2020012the Natural Science Foundation of Xiamen,China under contract No.3502Z20227246the Guiding Project of the Science and Technology Plan of Fujian Province under contract No.2020Y0081.
文摘The biogeochemical processes of marine sediments are influenced by bioturbation and organic carbon decomposition,which is crucial for understanding global element cycles and climate change.Two sediment cores were acquired in 2017 from abyssal basins in the central-eastern tropical Pacific to determine the bioturbation and organic carbon degradation processes.The radioactivity concentrations of 210Pb and 226Ra in the sediment cores were measured,indicating the presence of significant excess 210Pb(210Pbex)signals in the sediment cores.Besides,a manganese nodule was discovered in one core,which had a substantial influence on the distribution of 210Pbex.With the exception of this anomalous finding,the bioturbation coefficients in the remaining core were estimated to be 10.6 cm^(2)/a using a steady-state diffusion model,greater than most of the deep-sea sediments from the equatorial eastern Pacific.By using a bio-diffusion model,we further calculated the degradation rates of organic carbon(8.02 ka-1),which is also higher than other areas of the Pacific.Our findings displayed the presence of a biologically active benthic ecosystem in the central-eastern tropical Pacific.
基金This work was supported by the Natural Science Foundation of Guangdong Province(Grant No.2019A1515011354).
文摘Genome sequencing has revealed frequent mutations in Ras homolog family member A(RHOA)among various cancers with unique aberrant profiles and pathogenic effects,especially in peripheral T-cell lymphoma(PTCL).The discrete positional distribution and types of RHOA amino acid substitutions vary according to the tumor type,thereby leading to different functional and biological properties,which provide new insight into the molecular pathogenesis and potential targeted therapies for various tumors.However,the similarities and discrepancies in characteristics of RHOA mutations among various histologic subtypes of PTCL have not been fully elucidated.Herein we highlight the inconsistencies and complexities of the type and location of RHOA mutations and demonstrate the contribution of RHOA variants to the pathogenesis of PTCL by combining epigenetic abnormalities and activating multiple downstream pathways.The promising potential of targeting RHOA as a therapeutic modality is also outlined.This review provides new insight in the field of personalized medicine to improve the clinical outcomes for patients.
基金Supported by State Administration of Traditional Chinese Medicine High-level Key Discipline Construction Project of Traditional Chinese Medicine-Ethnic Minority Pharmacy (Zhuang Pharmacy) (zyyzdxk-2023165)Young Talent Cultivation Program of Guangxi International Zhuang Medicine Hospital (2022001)+4 种基金Key R&D Project of Guangxi Science and Technology Department (Guike AB21196057)Guangxi Traditional Chinese Medicine Interdisciplinary Innovation Team Project (GZKJ2309)Funding Project of High-level Talent Cultivation and Innovation Team of Guangxi University of Chinese Medicine (2022A008)The Third Batch of"Qihuang Project"High-Level Talent Team Training Project of Guangxi University of Chinese Medicine (202414)Three-year Action Plan for the Construction of High-level Talents Team of Guangxi International Zhuang Medicine Hospital in 2023 (GZCX20231203).
文摘[Objectives]To investigate the anti-inflammatory effect of Embelia parviflora Wall.polysaccharide on rheumatoid arthritis(RA)in rats.[Methods]RA rat model was induced by type II collagen.After successful modeling,the rats were divided into model group,positive group,low,medium and high dose of E.parviflora Wall.polysaccharide groups,and normal control group.Body mass,toe volume and arthritis index were measured,and thymus index and spleen index were calculated.The levels of interleukin-1β,interleukin-6 and tumor necrosis factor-αin serum and synovial tissue of ankle joint were detected by ELISA.[Results]Compared with the normal control group,the pathological changes such as synovial hyperplasia and unclear layer were observed in the model group,the body mass was decreased(P<0.05),the toe volume,arthritis index,thymus and spleen index were increased(P<0.05),and the levels of IL-1β,IL-6 and TNF-αin serum and ankle synovial tissue were increased(P<0.05).Compared with the model group,the histopathological changes in synovium of ankle joint in the positive group and the medium and high dose groups of E.parviflora Wall.polysaccharide were significantly improved,and the body mass was increased(P<0.05).The toe volume,arthritis index,thymus index and spleen index were decreased(P<0.05).The levels of IL-Iβ,IL-6 and TNF-αin serum and synovial tissue of ankle joint were increased(P<0.05),while there was no significant difference between the low dose group of E.parviflora Wall.polysaccharide and the model group(P>0.05).[Conclusions]E.parviflora Wall.polysaccharide can reduce the body's inflammatory response and improve RA,which may be related to the inhibition of the activation of inflammatory cytokines IL-1β,IL-6 and TNF-α.