Dysregulation of G9a,a histone-lysine N-methyltransferase,has been observed in Alzheimer’s disease and has been correlated with increased levels of chronic inflammation and oxidative stress.Likewise,microRNAs are inv...Dysregulation of G9a,a histone-lysine N-methyltransferase,has been observed in Alzheimer’s disease and has been correlated with increased levels of chronic inflammation and oxidative stress.Likewise,microRNAs are involved in many biological processes and diseases playing a key role in pathogenesis,especially in multifactorial diseases such as Alzheimer’s disease.Therefore,our aim has been to provide partial insights into the interconnection between G9a,microRNAs,oxidative stress,and neuroinflammation.To better understand the biology of G9a,we compared the global microRNA expression between senescence-accelerated mouse-prone 8(SAMP8)control mice and SAMP8 treated with G9a inhibitor UNC0642.We found a downregulation of miR-128 after a G9a inhibition treatment,which interestingly binds to the 3′untranslated region(3′-UTR)of peroxisome-proliferator activator receptor γ(PPARG)mRNA.Accordingly,Pparg gene expression levels were higher in the SAMP8 group treated with G9a inhibitor than in the SAMP8 control group.We also observed modulation of oxidative stress responses might be mainly driven Pparg after G9a inhibitor.To confirm these antioxidant effects,we treated primary neuron cell cultures with hydrogen peroxide as an oxidative insult.In this setting,treatment with G9a inhibitor increases both cell survival and antioxidant enzymes.Moreover,up-regulation of PPARγby G9a inhibitor could also increase the expression of genes involved in DNA damage responses and apoptosis.In addition,we also described that the PPARγ/AMPK axis partially explains the regulation of autophagy markers expression.Finally,PPARγ/GADD45αpotentially contributes to enhancing synaptic plasticity and neurogenesis after G9a inhibition.Altogether,we propose that pharmacological inhibition of G9a leads to a neuroprotective effect that could be due,at least in part,by the modulation of PPARγ-dependent pathways by miR-128.展开更多
BACKGROUND： MicroRNA （miRNA） expression in stem cells provides important clues for the molecular mechanisms of stem cell proliferation and differentiation. Bone marrow stromal cells and spinal cord-derived neural s...BACKGROUND： MicroRNA （miRNA） expression in stem cells provides important clues for the molecular mechanisms of stem cell proliferation and differentiation. Bone marrow stromal cells and spinal cord-derived neural stem cells exhibit potential for neural regeneration. However, miRNA expression in these cells has been rarely reported. OBJECTIVE： To explore differential expression of two nervous system-specific miRNAs, miR-124 and miR-128, in bone marrow stromal cells and spinal cord-derived neural stem cells. DESIGN, TIME AND SETTING： An In vitro, cell biology experiment was performed at the Department of Biotechnology, Shanxi Medical University from June 2008 to June 2009. MATERIALS： TaqMan miRNA assays were purchased from Applied Biosystems. METHODS： Rat bone marrow stromal cells were isolated and cultured using the whole-bone marrow method, and rat spinal cord-derived neural stem cells were obtained through neurosphere formation. TaqMan miRNA assays were used to measure miR-124 and miR-128 expression in bone marrow stromal cells and spinal cord-derived neural stem cells. MAIN OUTCOME MEASURES： Morphology of bone marrow stromal cells and spinal cord-derived neural stem cells were observed by inverted microscopy. Expression of the neural stem cell-specific marker, nestin, the bone marrow stromal cell surface marker, CD71, and expression of miR-124 and miR-128, were detected by real-time polymerase chain reaction. RESULTS： Cultured bone marrow stromal cells displayed a short fusiform shape. Flow cytometry revealed a large number of CD71-positive cells （〉 95%）. Cultured spinal cord-derived neural stem cells formed nestin-positive neurospheres, and quantitative detection of miRNA demonstrated that less miR-124 and miR-128 was expressed in bone marrow stromal cells compared to spinal cord-derived neural stem cells （P 〈 0.05）. CONCLUSION： Bone marrow stromal cells and spinal cord-derived neural stem cells exhibited differential expression of miR-124 and miR-128, which suggested different 展开更多
基金supported by the Ministerio de Economía,Industria y Competitividad(Agencia Estatal de Investigación,AEI,to CGF and MP)Fondo Europeo de Desarrollo Regional(MINECO-FEDER)(PID2022-139016OA-I00,PDC2022-133441-I00,to CGF and MP),Generalitat de Catalunya(2021 SGR 00357+3 种基金to CGF and MP)co-financed by Secretaria d’Universitats i Recerca del Departament d’Empresai Coneixement de la Generalitat de Catalunya 2021(Llavor 00086,to CGF)the recipient of an Alzheimer’s Association Research Fellowship(AARF-21-848511)the Agència de Gestiód’Ajuts Universitaris i de Recerca(AGAUR)for her FI-SDUR fellowship(2021FISDU 00182).
文摘Dysregulation of G9a,a histone-lysine N-methyltransferase,has been observed in Alzheimer’s disease and has been correlated with increased levels of chronic inflammation and oxidative stress.Likewise,microRNAs are involved in many biological processes and diseases playing a key role in pathogenesis,especially in multifactorial diseases such as Alzheimer’s disease.Therefore,our aim has been to provide partial insights into the interconnection between G9a,microRNAs,oxidative stress,and neuroinflammation.To better understand the biology of G9a,we compared the global microRNA expression between senescence-accelerated mouse-prone 8(SAMP8)control mice and SAMP8 treated with G9a inhibitor UNC0642.We found a downregulation of miR-128 after a G9a inhibition treatment,which interestingly binds to the 3′untranslated region(3′-UTR)of peroxisome-proliferator activator receptor γ(PPARG)mRNA.Accordingly,Pparg gene expression levels were higher in the SAMP8 group treated with G9a inhibitor than in the SAMP8 control group.We also observed modulation of oxidative stress responses might be mainly driven Pparg after G9a inhibitor.To confirm these antioxidant effects,we treated primary neuron cell cultures with hydrogen peroxide as an oxidative insult.In this setting,treatment with G9a inhibitor increases both cell survival and antioxidant enzymes.Moreover,up-regulation of PPARγby G9a inhibitor could also increase the expression of genes involved in DNA damage responses and apoptosis.In addition,we also described that the PPARγ/AMPK axis partially explains the regulation of autophagy markers expression.Finally,PPARγ/GADD45αpotentially contributes to enhancing synaptic plasticity and neurogenesis after G9a inhibition.Altogether,we propose that pharmacological inhibition of G9a leads to a neuroprotective effect that could be due,at least in part,by the modulation of PPARγ-dependent pathways by miR-128.
基金the National Natural Science Foundation of China, No. 30672114
文摘BACKGROUND： MicroRNA （miRNA） expression in stem cells provides important clues for the molecular mechanisms of stem cell proliferation and differentiation. Bone marrow stromal cells and spinal cord-derived neural stem cells exhibit potential for neural regeneration. However, miRNA expression in these cells has been rarely reported. OBJECTIVE： To explore differential expression of two nervous system-specific miRNAs, miR-124 and miR-128, in bone marrow stromal cells and spinal cord-derived neural stem cells. DESIGN, TIME AND SETTING： An In vitro, cell biology experiment was performed at the Department of Biotechnology, Shanxi Medical University from June 2008 to June 2009. MATERIALS： TaqMan miRNA assays were purchased from Applied Biosystems. METHODS： Rat bone marrow stromal cells were isolated and cultured using the whole-bone marrow method, and rat spinal cord-derived neural stem cells were obtained through neurosphere formation. TaqMan miRNA assays were used to measure miR-124 and miR-128 expression in bone marrow stromal cells and spinal cord-derived neural stem cells. MAIN OUTCOME MEASURES： Morphology of bone marrow stromal cells and spinal cord-derived neural stem cells were observed by inverted microscopy. Expression of the neural stem cell-specific marker, nestin, the bone marrow stromal cell surface marker, CD71, and expression of miR-124 and miR-128, were detected by real-time polymerase chain reaction. RESULTS： Cultured bone marrow stromal cells displayed a short fusiform shape. Flow cytometry revealed a large number of CD71-positive cells （〉 95%）. Cultured spinal cord-derived neural stem cells formed nestin-positive neurospheres, and quantitative detection of miRNA demonstrated that less miR-124 and miR-128 was expressed in bone marrow stromal cells compared to spinal cord-derived neural stem cells （P 〈 0.05）. CONCLUSION： Bone marrow stromal cells and spinal cord-derived neural stem cells exhibited differential expression of miR-124 and miR-128, which suggested different
