Adult neurogenesis is a highly dynamic process that leads to the production of new neurons from a population of quiescent neural stem cells(NSCs).In response to specific endogenous and/or external stimuli,NSCs enter a...Adult neurogenesis is a highly dynamic process that leads to the production of new neurons from a population of quiescent neural stem cells(NSCs).In response to specific endogenous and/or external stimuli,NSCs enter a state of mitotic activation,initiating proliferation and differentiation pathways.Throughout this process,NSCs give rise to neural progenitors,which undergo multiple replicative and differentiative steps,each governed by precise molecular pathways that coordinate cellular changes and signals from the surrounding neurogenic niche.展开更多
Background:Intracerebral hemorrhage(ICH)remains a devastating neurological disorder with limited therapeutic options.Neural stem cell(NSC)-based therapies have emerged as a potential regenerative approach,yet the mole...Background:Intracerebral hemorrhage(ICH)remains a devastating neurological disorder with limited therapeutic options.Neural stem cell(NSC)-based therapies have emerged as a potential regenerative approach,yet the molecular mechanisms regulating NSC behavior require further elucidation.The role of miR-21 in NSC differentiation and proliferation during ICH recovery remains unexplored.Methods:In vitro NSC cultures were analyzed for miR-21 expression dynamics during differentiation via qPCR.Lentiviral overexpression and knockdown of miR-21 were employed to assess its functional impact.The SOX2/LIN28-let-7 pathway was investigated using Western blot,luciferase reporter assays,and immunofluorescence.In vivo,miR-21-overexpressing NSCs were transplanted into a murine ICH model,with neurogenesis evaluated by immunostaining and neurological recovery assessed through behavioral tests(mNSS,rotarod).Results:miR-21 expression significantly increased during NSC differentiation,correlating with reduced SOX2 levels.Mechanistically,miR-21 directly targeted SOX2,disrupting the SOX2/LIN28-let-7 axis to promote NSC proliferation and lineage commitment.In ICH mice,transplantation of miR-21-overexpressing NSCs enhanced neurogenesis and improved motor coordination and neurological deficits at 28 days post-transplantation.Conclusions:Our findings identify miR-21 as a critical regulator of NSC plasticity through SOX2/LIN28-let-7 signaling,highlighting its therapeutic potential for enhancing neuroregeneration and functional recovery in ICH.Targeting miR-21 may represent a novel strategy to optimize NSC-based therapies for hemorrhagic stroke.展开更多
As a frequently-observed phenomenon in the northern South China Sea(nSCS),subsurface chlorophyll maximum(SCM)evolution from summer to winter remains unclear,neither the associated hydrographic control.In this study,on...As a frequently-observed phenomenon in the northern South China Sea(nSCS),subsurface chlorophyll maximum(SCM)evolution from summer to winter remains unclear,neither the associated hydrographic control.In this study,on the basis of in-situ data of fall-season cruises in 2004–2006,we characterized the depth,thickness and intensity of the SCM in the nSCS using a general Gaussian-function fitting approach,and investigated a linkage to the corresponding ocean vertical buoyance properties.Our results show that the SCM becomes deeper,thicker and less intense offshore-wards in the nSCS during fall seasons.In parallel,a correlation between the SCM variation and mixed layer depth exists in the nSCS,and it becomes pronounced in the shelf region compared to the slope and basin areas in autumn.Physically,once warmer surface ocean and thus stronger thermo-determined stratification,the SCM layer goes deeper and becomes thicker and less intense in the nSCS,especially in the shelf area of the nSCS.Moreover,the impact of water temperatures at deeper layers on the vertical stratification exerts more consequent roles on the spatial variability of SCM,compared to surface temperatures in the nSCS.Specifically,the isotherm line of 22℃ acts as crucial indicator for variations of the SCM in the nSCS during autumns.展开更多
文摘Adult neurogenesis is a highly dynamic process that leads to the production of new neurons from a population of quiescent neural stem cells(NSCs).In response to specific endogenous and/or external stimuli,NSCs enter a state of mitotic activation,initiating proliferation and differentiation pathways.Throughout this process,NSCs give rise to neural progenitors,which undergo multiple replicative and differentiative steps,each governed by precise molecular pathways that coordinate cellular changes and signals from the surrounding neurogenic niche.
基金Shanghai Minhang District Health Commission Project,Grant/Award Number:2022MHZ062Shanghai Sixth People's Hospital,Grant/Award Number:ynhg202311 and ynms202411。
文摘Background:Intracerebral hemorrhage(ICH)remains a devastating neurological disorder with limited therapeutic options.Neural stem cell(NSC)-based therapies have emerged as a potential regenerative approach,yet the molecular mechanisms regulating NSC behavior require further elucidation.The role of miR-21 in NSC differentiation and proliferation during ICH recovery remains unexplored.Methods:In vitro NSC cultures were analyzed for miR-21 expression dynamics during differentiation via qPCR.Lentiviral overexpression and knockdown of miR-21 were employed to assess its functional impact.The SOX2/LIN28-let-7 pathway was investigated using Western blot,luciferase reporter assays,and immunofluorescence.In vivo,miR-21-overexpressing NSCs were transplanted into a murine ICH model,with neurogenesis evaluated by immunostaining and neurological recovery assessed through behavioral tests(mNSS,rotarod).Results:miR-21 expression significantly increased during NSC differentiation,correlating with reduced SOX2 levels.Mechanistically,miR-21 directly targeted SOX2,disrupting the SOX2/LIN28-let-7 axis to promote NSC proliferation and lineage commitment.In ICH mice,transplantation of miR-21-overexpressing NSCs enhanced neurogenesis and improved motor coordination and neurological deficits at 28 days post-transplantation.Conclusions:Our findings identify miR-21 as a critical regulator of NSC plasticity through SOX2/LIN28-let-7 signaling,highlighting its therapeutic potential for enhancing neuroregeneration and functional recovery in ICH.Targeting miR-21 may represent a novel strategy to optimize NSC-based therapies for hemorrhagic stroke.
基金Supported by the Ministry of Science and Technology of the People’s Republic of China(No.2019 YFE 0125000)the National Natural Science Foundation of China-Shandong Joint Fund(No.U 1906215)+1 种基金the National Natural Science Foundation of China(No.41406010)partially by the Key Laboratory of Coastal Environmental Processes and Ecological Remediation,Chinese Academy of Sciences Opening Fund(No.2020 KFJJ 04)。
文摘As a frequently-observed phenomenon in the northern South China Sea(nSCS),subsurface chlorophyll maximum(SCM)evolution from summer to winter remains unclear,neither the associated hydrographic control.In this study,on the basis of in-situ data of fall-season cruises in 2004–2006,we characterized the depth,thickness and intensity of the SCM in the nSCS using a general Gaussian-function fitting approach,and investigated a linkage to the corresponding ocean vertical buoyance properties.Our results show that the SCM becomes deeper,thicker and less intense offshore-wards in the nSCS during fall seasons.In parallel,a correlation between the SCM variation and mixed layer depth exists in the nSCS,and it becomes pronounced in the shelf region compared to the slope and basin areas in autumn.Physically,once warmer surface ocean and thus stronger thermo-determined stratification,the SCM layer goes deeper and becomes thicker and less intense in the nSCS,especially in the shelf area of the nSCS.Moreover,the impact of water temperatures at deeper layers on the vertical stratification exerts more consequent roles on the spatial variability of SCM,compared to surface temperatures in the nSCS.Specifically,the isotherm line of 22℃ acts as crucial indicator for variations of the SCM in the nSCS during autumns.
