Tooth morphogenesis is orchestrated by a complex interplay of signaling pathways and transcription factors that control cell proliferation,apoptosis,and differentiation,with the Wnt/β-catenin signaling pathway playin...Tooth morphogenesis is orchestrated by a complex interplay of signaling pathways and transcription factors that control cell proliferation,apoptosis,and differentiation,with the Wnt/β-catenin signaling pathway playing a pivotal role.However,the comprehensive regulatory mechanisms of Wnt/β-catenin signaling remain largely unclear.Smad7,a key antagonist of the TGF-βsuperfamily,is essential for maintaining tissue homeostasis and ensuring proper cellular function.Our previous study has demonstrated that Smad7 knockout in mice leads to impaired proliferative property of tooth germ cells,resulting in small molars.Here,we identified SMAD7 expression in human dental papilla and dental pulp,colocalized with β-CATENIN and cell proliferationrelated proteins.RNA sequencing analysis revealed a significant reduction in Wnt signaling activity in Smad7-deficient mouse tooth germs.Using lentivirus transfection,we established SMAD7-knockdown human dental papilla stem cells,which manifested remarkably blunt proliferation rate,along with diminished Wnt signaling activity.In vivo transplantation investigations further revealed the indispensable role of SMAD7 in dentin formation.Mechanistically,we revealed that β-CATENIN interacts with P-SMAD2/3 and SMAD7 through co-immunoprecipitation and yeast two-hybrid assays.Inhibition of TGF-β pathway or disruption of SMAD7/β-CATENIN transcription factor complex formation potently impacted Wnt/β-catenin activities,indicating both direct and indirect regulatory mechanisms.These findings highlight the critical role of SMAD7 in the proliferation and diffe rentiation of human dental stem cells,which could contribute to dental tissue regeneration and engineering.展开更多
The activation of the sirtuin1(SIRT1)/nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase 1(HO-1)pathway has been shown to mitigate oxidative stress-induced apoptosis and mitochondrial damage by reducing ...The activation of the sirtuin1(SIRT1)/nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase 1(HO-1)pathway has been shown to mitigate oxidative stress-induced apoptosis and mitochondrial damage by reducing reactive oxygen species(ROS)levels.Clinical trials have demonstrated that Zhongfeng Xingnao Liquid(ZFXN)ameliorates post-stroke cognitive impairment(PSCI).However,the underlying mechanism,particularly whether it involves protecting mitochondria and inhibiting apoptosis through the SIRT1/Nrf2/HO-1 pathway,remains unclear.This study employed an oxygen-glucose deprivation(OGD)cell model using SHSY5Y cells and induced PSCI in rats through modified bilateral carotid artery ligation(2VO).The effects of ZFXN on learning and memory,neuroprotective activity,mitochondrial function,oxidative stress,and the SIRT1/Nrf2/HO-1 pathway were evaluated both in vivo and in vitro.Results indicated that ZFXN significantly increased the B-cell lymphoma 2(Bcl2)/Bcl2-associated X(Bax)ratio,reduced terminal deoxynucleotidyl transferase-mediated d UTP nickend-labeling(TUNEL)+cells,and markedly improved cognition,synaptic plasticity,and neuronal function in the hippocampus and cortex.Furthermore,ZFXN exhibited potent antioxidant activity,evidenced by decreased ROS and malondialdehyde(MDA)content and increased superoxide dismutase(SOD),catalase(CAT),and glutathione(GSH)levels.ZFXN also demonstrated considerable enhancement of mitochondrial membrane potential(MMP),Tom 20 fluorescence intensity,adenosine triphosphate(ATP)and energy charge(EC)levels,and mitochondrial complexⅠandⅢactivity,thereby inhibiting mitochondrial damage.Additionally,ZFXN significantly increased SIRT1 activity and elevated SIRT1,nuclear Nrf2,and HO-1 levels.Notably,these effects were substantially counteracted when SIRT1 was suppressed by the inhibitor EX-527 in vitro.In conclusion,ZFXN alleviates PSCI by activating the SIRT1/Nrf2/HO-1 pathway and preventing mitochondrial damage.展开更多
Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in s...Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in spinal cord injury.Previous studies have shown that microglia can promote neuronal survival by phagocytosing dead cells and debris and by releasing neuroprotective and anti-inflammatory factors.However,excessive activation of microglia can lead to persistent inflammation and contribute to the formation of glial scars,which hinder axonal regeneration.Despite this,the precise role and mechanisms of microglia during the acute phase of spinal cord injury remain controversial and poorly understood.To elucidate the role of microglia in spinal cord injury,we employed the colony-stimulating factor 1 receptor inhibitor PLX5622 to deplete microglia.We observed that sustained depletion of microglia resulted in an expansion of the lesion area,downregulation of brain-derived neurotrophic factor,and impaired functional recovery after spinal cord injury.Next,we generated a transgenic mouse line with conditional overexpression of brain-derived neurotrophic factor specifically in microglia.We found that brain-derived neurotrophic factor overexpression in microglia increased angiogenesis and blood flow following spinal cord injury and facilitated the recovery of hindlimb motor function.Additionally,brain-derived neurotrophic factor overexpression in microglia reduced inflammation and neuronal apoptosis during the acute phase of spinal cord injury.Furthermore,through using specific transgenic mouse lines,TMEM119,and the colony-stimulating factor 1 receptor inhibitor PLX73086,we demonstrated that the neuroprotective effects were predominantly due to brain-derived neurotrophic factor overexpression in microglia rather than macrophages.In conclusion,our findings suggest the critical role of microglia in the formation of protective glial scars.Depleting microglia is detrimental to recovery of spinal cord injury,whereas targeting brain-derived neurotrophic factor overexpression in microglia represents a promising and novel therapeutic strategy to enhance motor function recovery in patients with spinal cord injury.展开更多
Strokes include both ischemic stroke,which is mediated by a blockade or reduction in the blood supply to the brain,and hemorrhagic stroke,which comprises intracerebral hemorrhage and subarachnoid hemorrhage and is cha...Strokes include both ischemic stroke,which is mediated by a blockade or reduction in the blood supply to the brain,and hemorrhagic stroke,which comprises intracerebral hemorrhage and subarachnoid hemorrhage and is characterized by bleeding within the brain.Stroke is a lifethreatening cerebrovascular condition characterized by intricate pathophysiological mechanisms,including oxidative stress,inflammation,mitochondrial dysfunction,and neuronal injury.Critical transcription factors,such as nuclear factor erythroid 2-related factor 2 and nuclear factor kappa B,play central roles in the progression of stroke.Nuclear factor erythroid 2-related factor 2 is sensitive to changes in the cellular redox status and is crucial in protecting cells against oxidative damage,inflammatory responses,and cytotoxic agents.It plays a significant role in post-stroke neuroprotection and repair by influencing mitochondrial function,endoplasmic reticulum stress,and lysosomal activity and regulating metabolic pathways and cytokine expression.Conversely,nuclear factor-kappa B is closely associated with mitochondrial dysfunction,the generation of reactive oxygen species,oxidative stress exacerbation,and inflammation.Nuclear factor-kappa B contributes to neuronal injury,apoptosis,and immune responses following stroke by modulating cell adhesion molecules and inflammatory mediators.The interplay between these pathways,potentially involving crosstalk among various organelles,significantly influences stroke pathophysiology.Advancements in single-cell sequencing and spatial transcriptomics have greatly improved our understanding of stroke pathogenesis and offer new opportunities for the development of targeted,individualized,cell typespecific treatments.In this review,we discuss the mechanisms underlying the involvement of nuclear factor erythroid 2-related factor 2 and nuclear factor-kappa B in both ischemic and hemorrhagic stroke,with an emphasis on their roles in oxidative stress,inflammation,and neuroprotection.展开更多
Purpose:Journal Impact Factors and other citation-based indicators are widely used and abused to help select journals to publish in or to estimate the value of a published article.Nevertheless,citation rates primarily...Purpose:Journal Impact Factors and other citation-based indicators are widely used and abused to help select journals to publish in or to estimate the value of a published article.Nevertheless,citation rates primarily reflect scholarly impact rather than other quality dimensions,including societal impact,originality,and rigour.In response to this deficit,Journal Quality Factors(JQFs)are defined and evaluated.These are average quality score estimates given to a journal’s articles by ChatGPT.Design/methodology/approach:JQFs were compared with Polish,Norwegian and Finnish journal ranks and with journal citation rates for 1,300 journals with 130,000 articles from 2021 in large monodisciplinary journals in the 25 out of 27 Scopus broad fields of research for which it was possible.Outliers were also examined.Findings:JQFs correlated positively and mostly strongly(median correlation:0.641)with journal ranks in 24 out of the 25 broad fields examined,indicating a nearly science-wide ability for ChatGPT to estimate journal quality.Journal citation rates had similarly high correlations with national journal ranks,however,so JQFs are not a universally better indicator.An examination of journals with JQFs not matching their journal ranks suggested that abstract styles may affect the result,such as whether the societal contexts of research are mentioned.Research limitations:Different journal rankings may have given different findings because there is no agreed meaning for journal quality.Practical implications:The results suggest that JQFs are plausible as journal quality indicators in all fields and may be useful for the(few)research and evaluation contexts where journal quality is an acceptable proxy for article quality,and especially for fields like mathematics for which citations are not strong indicators of quality.Originality/value:This is the first attempt to estimate academic journal value with a Large Language Model.展开更多
基金supported by the National Key Research and Development Program of China to W.Tian (2022YFA1104400)the National Natural Science Foundation of China to T.Chen (82100959)a grant from the Sichuan Science and Technology Program to Z.Liu (2024YFFK0068)。
文摘Tooth morphogenesis is orchestrated by a complex interplay of signaling pathways and transcription factors that control cell proliferation,apoptosis,and differentiation,with the Wnt/β-catenin signaling pathway playing a pivotal role.However,the comprehensive regulatory mechanisms of Wnt/β-catenin signaling remain largely unclear.Smad7,a key antagonist of the TGF-βsuperfamily,is essential for maintaining tissue homeostasis and ensuring proper cellular function.Our previous study has demonstrated that Smad7 knockout in mice leads to impaired proliferative property of tooth germ cells,resulting in small molars.Here,we identified SMAD7 expression in human dental papilla and dental pulp,colocalized with β-CATENIN and cell proliferationrelated proteins.RNA sequencing analysis revealed a significant reduction in Wnt signaling activity in Smad7-deficient mouse tooth germs.Using lentivirus transfection,we established SMAD7-knockdown human dental papilla stem cells,which manifested remarkably blunt proliferation rate,along with diminished Wnt signaling activity.In vivo transplantation investigations further revealed the indispensable role of SMAD7 in dentin formation.Mechanistically,we revealed that β-CATENIN interacts with P-SMAD2/3 and SMAD7 through co-immunoprecipitation and yeast two-hybrid assays.Inhibition of TGF-β pathway or disruption of SMAD7/β-CATENIN transcription factor complex formation potently impacted Wnt/β-catenin activities,indicating both direct and indirect regulatory mechanisms.These findings highlight the critical role of SMAD7 in the proliferation and diffe rentiation of human dental stem cells,which could contribute to dental tissue regeneration and engineering.
基金supported by the Science&Technology Department of Sichuan Province(No.2019YFS0040)the Improvement Plan of“Xinglin Scholar”Scientific Research Talent,Chengdu University of Traditional Chinese Medicine(No.XKTD2022002)。
文摘The activation of the sirtuin1(SIRT1)/nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase 1(HO-1)pathway has been shown to mitigate oxidative stress-induced apoptosis and mitochondrial damage by reducing reactive oxygen species(ROS)levels.Clinical trials have demonstrated that Zhongfeng Xingnao Liquid(ZFXN)ameliorates post-stroke cognitive impairment(PSCI).However,the underlying mechanism,particularly whether it involves protecting mitochondria and inhibiting apoptosis through the SIRT1/Nrf2/HO-1 pathway,remains unclear.This study employed an oxygen-glucose deprivation(OGD)cell model using SHSY5Y cells and induced PSCI in rats through modified bilateral carotid artery ligation(2VO).The effects of ZFXN on learning and memory,neuroprotective activity,mitochondrial function,oxidative stress,and the SIRT1/Nrf2/HO-1 pathway were evaluated both in vivo and in vitro.Results indicated that ZFXN significantly increased the B-cell lymphoma 2(Bcl2)/Bcl2-associated X(Bax)ratio,reduced terminal deoxynucleotidyl transferase-mediated d UTP nickend-labeling(TUNEL)+cells,and markedly improved cognition,synaptic plasticity,and neuronal function in the hippocampus and cortex.Furthermore,ZFXN exhibited potent antioxidant activity,evidenced by decreased ROS and malondialdehyde(MDA)content and increased superoxide dismutase(SOD),catalase(CAT),and glutathione(GSH)levels.ZFXN also demonstrated considerable enhancement of mitochondrial membrane potential(MMP),Tom 20 fluorescence intensity,adenosine triphosphate(ATP)and energy charge(EC)levels,and mitochondrial complexⅠandⅢactivity,thereby inhibiting mitochondrial damage.Additionally,ZFXN significantly increased SIRT1 activity and elevated SIRT1,nuclear Nrf2,and HO-1 levels.Notably,these effects were substantially counteracted when SIRT1 was suppressed by the inhibitor EX-527 in vitro.In conclusion,ZFXN alleviates PSCI by activating the SIRT1/Nrf2/HO-1 pathway and preventing mitochondrial damage.
基金supported by the National Natural Science Foundation of China,Nos.82072165 and 82272256(both to XM)the Key Project of Xiangyang Central Hospital,No.2023YZ03(to RM)。
文摘Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in spinal cord injury.Previous studies have shown that microglia can promote neuronal survival by phagocytosing dead cells and debris and by releasing neuroprotective and anti-inflammatory factors.However,excessive activation of microglia can lead to persistent inflammation and contribute to the formation of glial scars,which hinder axonal regeneration.Despite this,the precise role and mechanisms of microglia during the acute phase of spinal cord injury remain controversial and poorly understood.To elucidate the role of microglia in spinal cord injury,we employed the colony-stimulating factor 1 receptor inhibitor PLX5622 to deplete microglia.We observed that sustained depletion of microglia resulted in an expansion of the lesion area,downregulation of brain-derived neurotrophic factor,and impaired functional recovery after spinal cord injury.Next,we generated a transgenic mouse line with conditional overexpression of brain-derived neurotrophic factor specifically in microglia.We found that brain-derived neurotrophic factor overexpression in microglia increased angiogenesis and blood flow following spinal cord injury and facilitated the recovery of hindlimb motor function.Additionally,brain-derived neurotrophic factor overexpression in microglia reduced inflammation and neuronal apoptosis during the acute phase of spinal cord injury.Furthermore,through using specific transgenic mouse lines,TMEM119,and the colony-stimulating factor 1 receptor inhibitor PLX73086,we demonstrated that the neuroprotective effects were predominantly due to brain-derived neurotrophic factor overexpression in microglia rather than macrophages.In conclusion,our findings suggest the critical role of microglia in the formation of protective glial scars.Depleting microglia is detrimental to recovery of spinal cord injury,whereas targeting brain-derived neurotrophic factor overexpression in microglia represents a promising and novel therapeutic strategy to enhance motor function recovery in patients with spinal cord injury.
基金supported by grants from the Zhejiang Provincial TCM Science and Technology Plan Project,No.2023ZL156(to YH)Ningbo Top Medical and Health Research Program,No.2022020304(to XG)+1 种基金the Natural Science Foundation of Ningbo,No.2023J019(to YH)Key Laboratory of Precision Medicine for Atherosclerotic Diseases of Zhejiang Province,No.2022E10026(to YH)。
文摘Strokes include both ischemic stroke,which is mediated by a blockade or reduction in the blood supply to the brain,and hemorrhagic stroke,which comprises intracerebral hemorrhage and subarachnoid hemorrhage and is characterized by bleeding within the brain.Stroke is a lifethreatening cerebrovascular condition characterized by intricate pathophysiological mechanisms,including oxidative stress,inflammation,mitochondrial dysfunction,and neuronal injury.Critical transcription factors,such as nuclear factor erythroid 2-related factor 2 and nuclear factor kappa B,play central roles in the progression of stroke.Nuclear factor erythroid 2-related factor 2 is sensitive to changes in the cellular redox status and is crucial in protecting cells against oxidative damage,inflammatory responses,and cytotoxic agents.It plays a significant role in post-stroke neuroprotection and repair by influencing mitochondrial function,endoplasmic reticulum stress,and lysosomal activity and regulating metabolic pathways and cytokine expression.Conversely,nuclear factor-kappa B is closely associated with mitochondrial dysfunction,the generation of reactive oxygen species,oxidative stress exacerbation,and inflammation.Nuclear factor-kappa B contributes to neuronal injury,apoptosis,and immune responses following stroke by modulating cell adhesion molecules and inflammatory mediators.The interplay between these pathways,potentially involving crosstalk among various organelles,significantly influences stroke pathophysiology.Advancements in single-cell sequencing and spatial transcriptomics have greatly improved our understanding of stroke pathogenesis and offer new opportunities for the development of targeted,individualized,cell typespecific treatments.In this review,we discuss the mechanisms underlying the involvement of nuclear factor erythroid 2-related factor 2 and nuclear factor-kappa B in both ischemic and hemorrhagic stroke,with an emphasis on their roles in oxidative stress,inflammation,and neuroprotection.
基金funded by the UKRI Economic and Social Research Council.
文摘Purpose:Journal Impact Factors and other citation-based indicators are widely used and abused to help select journals to publish in or to estimate the value of a published article.Nevertheless,citation rates primarily reflect scholarly impact rather than other quality dimensions,including societal impact,originality,and rigour.In response to this deficit,Journal Quality Factors(JQFs)are defined and evaluated.These are average quality score estimates given to a journal’s articles by ChatGPT.Design/methodology/approach:JQFs were compared with Polish,Norwegian and Finnish journal ranks and with journal citation rates for 1,300 journals with 130,000 articles from 2021 in large monodisciplinary journals in the 25 out of 27 Scopus broad fields of research for which it was possible.Outliers were also examined.Findings:JQFs correlated positively and mostly strongly(median correlation:0.641)with journal ranks in 24 out of the 25 broad fields examined,indicating a nearly science-wide ability for ChatGPT to estimate journal quality.Journal citation rates had similarly high correlations with national journal ranks,however,so JQFs are not a universally better indicator.An examination of journals with JQFs not matching their journal ranks suggested that abstract styles may affect the result,such as whether the societal contexts of research are mentioned.Research limitations:Different journal rankings may have given different findings because there is no agreed meaning for journal quality.Practical implications:The results suggest that JQFs are plausible as journal quality indicators in all fields and may be useful for the(few)research and evaluation contexts where journal quality is an acceptable proxy for article quality,and especially for fields like mathematics for which citations are not strong indicators of quality.Originality/value:This is the first attempt to estimate academic journal value with a Large Language Model.
