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1.
Nature ; 626(7998): 411-418, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38297130

RESUMO

Ferroptosis, a form of regulated cell death that is driven by iron-dependent phospholipid peroxidation, has been implicated in multiple diseases, including cancer1-3, degenerative disorders4 and organ ischaemia-reperfusion injury (IRI)5,6. Here, using genome-wide CRISPR-Cas9 screening, we identified that the enzymes involved in distal cholesterol biosynthesis have pivotal yet opposing roles in regulating ferroptosis through dictating the level of 7-dehydrocholesterol (7-DHC)-an intermediate metabolite of distal cholesterol biosynthesis that is synthesized by sterol C5-desaturase (SC5D) and metabolized by 7-DHC reductase (DHCR7) for cholesterol synthesis. We found that the pathway components, including MSMO1, CYP51A1, EBP and SC5D, function as potential suppressors of ferroptosis, whereas DHCR7 functions as a pro-ferroptotic gene. Mechanistically, 7-DHC dictates ferroptosis surveillance by using the conjugated diene to exert its anti-phospholipid autoxidation function and shields plasma and mitochondria membranes from phospholipid autoxidation. Importantly, blocking the biosynthesis of endogenous 7-DHC by pharmacological targeting of EBP induces ferroptosis and inhibits tumour growth, whereas increasing the 7-DHC level by inhibiting DHCR7 effectively promotes cancer metastasis and attenuates the progression of kidney IRI, supporting a critical function of this axis in vivo. In conclusion, our data reveal a role of 7-DHC as a natural anti-ferroptotic metabolite and suggest that pharmacological manipulation of 7-DHC levels is a promising therapeutic strategy for cancer and IRI.


Assuntos
Desidrocolesteróis , Ferroptose , Humanos , Membrana Celular/metabolismo , Colesterol/biossíntese , Colesterol/metabolismo , Sistemas CRISPR-Cas/genética , Desidrocolesteróis/metabolismo , Genoma Humano , Nefropatias/metabolismo , Membranas Mitocondriais/metabolismo , Metástase Neoplásica , Neoplasias/metabolismo , Neoplasias/patologia , Fosfolipídeos/metabolismo , Traumatismo por Reperfusão/metabolismo
2.
Cardiovasc Diabetol ; 23(1): 215, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907337

RESUMO

BACKGROUND: Circulating atherogenic index of plasma (AIP) levels has been proposed as a novel biomarker for dyslipidemia and as a predictor of insulin resistance (IR) risk. However, the association between AIP and the incidence of new-onset stroke, particularly in individuals with varying glucose metabolism status, remains ambiguous. METHODS: A total of 8727 participants aged 45 years or older without a history of stroke from the China Health and Retirement Longitudinal Study (CHARLS) were included in this study. The AIP was calculated using the formula log [Triglyceride (mg/dL) / High-density lipoprotein cholesterol (mg/dL)]. Participants were divided into four groups based on their baseline AIP levels: Q1 (AIP ≤ 0.122), Q2 (0.122 < AIP ≤ 0.329), Q3 (0.329 < AIP ≤ 0.562), and Q4 (AIP > 0.562). The primary endpoint was the occurrence of new-onset stroke events. The Kaplan-Meier curves, multivariate Cox proportional hazard models, and Restricted cubic spline analysis were applied to explore the association between baseline AIP levels and the risk of developing a stroke among individuals with varying glycemic metabolic states. RESULTS: During an average follow-up of 8.72 years, 734 participants (8.4%) had a first stroke event. The risk for stroke increased with each increasing quartile of baseline AIP levels. Kaplan-Meier curve analysis revealed a significant difference in stroke occurrence among the AIP groups in all participants, as well as in those with prediabetes mellitus (Pre-DM) and diabetes mellitus (DM) (all P values < 0.05). After adjusting for potential confounders, the risk of stroke was significantly higher in the Q2, Q3, and Q4 groups than in the Q1 group in all participants. The respective hazard ratios (95% confidence interval) for stroke in the Q2, Q3, and Q4 groups were 1.34 (1.05-1.71), 1.52 (1.19-1.93), and 1.84 (1.45-2.34). Furthermore, high levels of AIP were found to be linked to an increased risk of stroke in both pre-diabetic and diabetic participants across all three Cox models. However, this association was not observed in participants with normal glucose regulation (NGR) (p > 0.05). Restricted cubic spline analysis also demonstrated that higher baseline AIP levels were associated with higher hazard ratios for stroke in all participants and those with glucose metabolism disorders. CONCLUSIONS: An increase in baseline AIP levels was significantly associated with the risk of stroke in middle-aged and elderly individuals, and exhibited distinct characteristics depending on the individual's glucose metabolism status.


Assuntos
Biomarcadores , Glicemia , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Fatores de Risco , Idoso , Glicemia/metabolismo , Biomarcadores/sangue , China/epidemiologia , Medição de Risco , Incidência , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/diagnóstico , Fatores de Tempo , Estudos Longitudinais , Prognóstico , Resistência à Insulina , Triglicerídeos/sangue , HDL-Colesterol/sangue , Dislipidemias/sangue , Dislipidemias/epidemiologia , Dislipidemias/diagnóstico , Aterosclerose/sangue , Aterosclerose/epidemiologia , Aterosclerose/diagnóstico , Estudos Prospectivos
3.
Mol Cell ; 58(5): 804-18, 2015 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-25936802

RESUMO

mTORC1 is essential for regulating cell growth and metabolism in response to various environmental stimuli. Heterodimeric Rag GTPases are required for amino-acid-mediated mTORC1 activation at the lysosome. However, the mechanism by which amino acids regulate Rag activation remains not fully understood. Here, we identified the lysosome-anchored E3 ubiquitin ligase RNF152 as an essential negative regulator of the mTORC1 pathway by targeting RagA for K63-linked ubiquitination. RNF152 interacts with and ubiquitinates RagA in an amino-acid-sensitive manner. The mutation of RagA ubiquitination sites abolishes this effect of RNF152 and enhances the RagA-mediated activation of mTORC1. Ubiquitination by RNF152 generates an anchor on RagA to recruit its inhibitor GATOR1, a GAP complex for Rag GTPases. RNF152 knockout results in the hyperactivation of mTORC1 and protects cells from amino-acid-starvation-induced autophagy. Thus, this study reveals a mechanism for regulation of mTORC1 signaling by RNF152-mediated K63-linked polyubiquitination of RagA.


Assuntos
Proteínas Monoméricas de Ligação ao GTP/metabolismo , Complexos Multiproteicos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Ubiquitina-Proteína Ligases/fisiologia , Ubiquitinação , Sequência de Aminoácidos , Animais , Autofagia , Ativação Enzimática , Células HEK293 , Humanos , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos Knockout , Dados de Sequência Molecular , Fosforilação , Transporte Proteico , Transdução de Sinais , Proteína 1 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/metabolismo
4.
Environ Res ; 203: 111795, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34343556

RESUMO

BACKGROUND: During the COVID-19 epidemic period, people showed a stronger connection to the environment within their communities. Although tree canopy in residential areas has been shown to positively affect psychological distress, it is not clear whether the COVID-19 epidemic played a role in this process. Elucidation of the relationship between tree canopy and the impact on psychological distress during the COVID-19 epidemic could provide valuable information as to the best methods to help individuals cope with urban mental stress events. METHODS: A total of 15 randomly selected residential areas of Beijing were enrolled in this repeated cross-sectional study. A total of 900 residents were included in the two-waves of the investigation (450 residents per wave) before and during the COVID-19 epidemic (i.e., May 2019 and May 2020). Psychological distress was estimated using the 12-question General Health Questionnaire (GHQ-12). Tree canopy coverage (TCC) was measured through visual interpretation based on the 2013 data sources (World View 2 satellite imagery of Beijing urban areas with a resolution of 0.5 m). The demographic characteristics, distance to the nearest surrounding green or blue space, residential area house price, household density, and construction year were also collected in this study. A multivariate logistic regression, relative risk due to interaction (RERI), and synergy index (SI) were used to explore the relationships among tree canopy, COVID-19, and psychological distress. RESULTS: The negative impact of the COVID-19 epidemic on mental health was significant, with the prevalence of psychological distress increased 7.84 times (aOR = 7.84, 95% CI = 4.67-13.95) during the COVID-19 epidemic period. Tree canopy coverage in the group without psychological distress was significantly higher than that of the psychologically distressed group (31.07 ± 11.38% vs. 27.87 ± 12.97%, P = 0.005). An increase in 1% of TCC, was related to a 5% decrease in the prevalence of psychological distress (aOR = 0.95, 95% CI = 0.93-0.98). An antagonism joint action between tree canopy and the COVID-19 epidemic existed (RERI = 1.09, 95% CI = 0.72-1.47; SI = 0.16, 95% CI = 0.05-0.52), and persisted enhancing only in medium (26.45%-33.21%) and above TCC level. Correlation of GHQ items and TCC significantly differed between the COVID-19 non-epidemic and epidemic periods, with the effects of tree canopy on GHQ-12 items covering topics, such as social function and depression, presumably absent because of epidemic limitations. CONCLUSIONS: This study indicates that the COVID-19 epidemic harmed mental health and verified the positive effects of residential tree canopy on psychological distress in Beijing. We suggest paying more attention to residents in areas of low TCC and dealing with psychological distress caused by public health stress events based on tree canopy strategies.


Assuntos
COVID-19 , Epidemias , Angústia Psicológica , Estudos Transversais , Humanos , SARS-CoV-2 , Estresse Psicológico/epidemiologia , Árvores
5.
Mol Ther ; 29(9): 2873-2885, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33895326

RESUMO

Dysregulated long non-coding RNAs (lncRNAs) have been shown to contribute to the pathogenesis of ischemic stroke. However, the potential role of lncRNAs in post-stroke microglial activation remains largely unknown. Here, we uncovered that lncRNA-U90926 was significantly increased in microglia exposed to ischemia/reperfusion both in vivo and in vitro. In addition, adenovirus-associated virus (AAV)-mediated microglial U90926 silencing alleviated neurological deficits and reduced infarct volume in experimental stroke mice. Microglial U90926 knockdown could reduce the infiltration of neutrophils into ischemic lesion site, which might be attributed to the downregulation of C-X-C motif ligand 2 (CXCL2). Mechanistically, U90926 directly bound to malate dehydrogenase 2 (MDH2) and competitively inhibited the binding of MDH2 to the CXCL2 3' untranslated region (UTR), thus protecting against MDH2-mediated decay of CXCL2 mRNA. Taken together, our study demonstrated that microglial U90926 aggravated ischemic brain injury via facilitating neutrophil infiltration, suggesting that U90926 might be a potential biomarker and therapeutic target for ischemic stroke.


Assuntos
Quimiocina CXCL2/genética , AVC Isquêmico/imunologia , Malato Desidrogenase/genética , Microglia/química , RNA Longo não Codificante/genética , Regulação para Cima , Regiões 5' não Traduzidas , Animais , Células Cultivadas , Modelos Animais de Doenças , Células HEK293 , Humanos , AVC Isquêmico/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infiltração de Neutrófilos , Cultura Primária de Células
6.
Exp Mol Pathol ; 121: 104645, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33989616

RESUMO

We have focused on the underlying role of miR-1224 in cardiomyocyte injury stimulated by hypoxia/reoxygenation (H/R). In the current study, the rat cardiomyocyte cell line H9C2 was used to construct a H/R cell model to validate the cardioprotective effects of miR-1224. Data from the dual-luciferase assay revealed that the glutathione peroxidase 4 (GPX4) was a direct target of miR-1224. Expression of miR-1224, determined using qRT-PCR, was remarkably increased while that of GPX4 protein, evaluated via western blotting, was significantly decreased in cardiomyocytes in response to H/R exposure. ROS generation, superoxide dismutase (SOD) activity, concentrations of malondialdehyde (MDA) and 4-hydroxy aldehydes (4-HNE), and H9C2 cell apoptosis were further evaluated following overexpression of miR-1224 or silencing of GPX4 in H9C2 cells. H9C2 cells under H/R conditions displayed increased synthesis of ROS, along with overexpression of miR-1224 and downregulation of GPX4. SOD activity was significantly decreased while concentrations of MDA and 4-HNE were markedly increased under H/R injury conditions. In addition, miR-1224 mimic or GPX4 siRNA plasmids dramatically enhanced H/R-mediated apoptosis, Bax expression and caspase-3 activity, with a concomitant reduction in Bcl-2 expression. Conversely, inhibition of miR-1224 exerted suppressive effects on oxidative stress and apoptosis in H9C2 cells under H/R conditions. Interestingly, silencing of GPX4 attenuated the negative effects of miR-1224 inhibition. Our results suggested that inhibition of miR-1224 caused resistance to H/R and diminished oxidative stress in vitro through targeting of GPX4.


Assuntos
Apoptose , Hipóxia/fisiopatologia , MicroRNAs/antagonistas & inibidores , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/patologia , Estresse Oxidativo , Oxigênio/toxicidade , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/antagonistas & inibidores , Animais , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/metabolismo , Ratos
7.
J Pharmacol Sci ; 143(4): 245-254, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32482409

RESUMO

The accumulation of insoluble amyloid ß (Aß) peptides is one of the pathological changes in Alzheimer's disease (AD), which induced synaptic plasticity impairment and excitatory amino acid toxicity associated with decreased memory function. Xingnaojing (XNJ), a well-known prescription in traditional Chinese medicine, has been used for the treatment of stroke for many years in China. In this study, we aim to investigate the therapeutic effects of XNJ in a hippocampus of Aß1-42 induced mouse model of AD which showed significant memory loss and impaired synaptic morphology and function. Treatment of XNJ could attenuate spatial and working memory dysfunction, increase dendritic spine density and improve long-term potential (LTP) induction. In addition, XNJ treatment significantly increased the level of N-methyl-d-aspartate receptors (NMDARs) and inhibit the NMDA/α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) ratio in AD mice. XNJ treatment also activated the AKT/mechanistic target of rapamycin (mTOR) pathway, while inhibition of the mTOR pathway by rapamycin could reverse the protective effects of XNJ treatment. In conclusion, XNJ protected against synaptic plasticity and memory impairment in AD mice via the activation of AKT/mTOR signaling pathway, suggesting XNJ as an alternative treatment for AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Transtornos da Memória/tratamento farmacológico , Plasticidade Neuronal/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Doença de Alzheimer/metabolismo , Animais , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL
8.
J Clin Periodontol ; 47(4): 509-517, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31944341

RESUMO

AIM: This study measured the two-dimensional size of soft and hard tissues and analysed some relevance between them. MATERIAL AND METHODS: Ninety-six maxillary anterior implants with a follow-up time 1-7 years postoperatively were evaluated. We superimposed the CBCT data of 72 patients with the optical scan data, followed by the measurements of the thickness and the height of soft and bone tissues. The shoulder of the implant was the reference point for all vertical measurements. RESULTS: At the level of implant shoulder, the mid-buccal mean thickness of soft tissue was 1.83 ± 0.76 mm, and on the palatal side, it was 4.00 ± 1.22 mm. The mean height of mid-buccal and mid-palatal gingiva was 4.16 ± 1.07 mm and 4.27 ± 1.07 mm. The buccal and palatal vertical bone wall peak was 0.41 ± 0.73 mm and 0.22 ± 0.57 mm coronal to the implant shoulder, and the marginal bone loss was -0.28 ± 0.76 mm and -0.84 ± 1.41 mm. Correlation analysis showed that the soft tissue thickness was negatively correlated with the bone thickness at 0 mm on the buccal side and at 0/2/4 mm on the palatal side apical towards from implant shoulder. The gingival height was significantly positively correlated with bone peak height and marginal bone height. CONCLUSION: Soft and hard tissues were basically negatively correlated in the horizontal direction. Sites with little marginal bone loss or high bone peak positively correlated with higher soft tissue levels.


Assuntos
Implantes Dentários para Um Único Dente , Maxila , Processo Alveolar/diagnóstico por imagem , Estudos Transversais , Implantação Dentária Endóssea , Gengiva/diagnóstico por imagem , Gengiva/cirurgia , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Tempo
9.
Clin Oral Implants Res ; 31(5): 476-487, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31990412

RESUMO

OBJECTIVES: The purpose of this cone beam computed tomography (CBCT) study was to describe facial alveolar bone alterations and gray value (GV) changes around implants in aesthetic anterior maxilla with simultaneous guided bone regeneration (GBR) and to investigate potential influence of factors related to vertical alveolar bone stability, such as particle sizes of the deproteinized bovine bone mineral (DBBM) used. MATERIALS AND METHODS: A retrospective study design was adopted. Four facio-palatal cross-sectional CBCT images of 166 implants from 124 patients who had maxillary anterior implants were obtained. Measurements of the vertical facial alveolar bone level (VFBL), horizontal facial alveolar bone thickness (HFBT), and GV were identified of 1-3 years. Then, correlation coefficients for those parameters were calculated. Finally, linear mixed models were established to investigate potential factors influencing vertical alveolar bone resorption. RESULTS: Facial alveolar bone underwent fast bone modeling and remodeling during the first 6 months, with decreases of 1.00 ± 1.19 and 0.74 ± 0.86 mm in VFBL and HFBT in implant shoulder, respectively, and there was positive and significant correlation between the alterations in VFBL and HFBT1 (rs  = .516, p = .000). Linear mixed models identified particle size of DBBM as a critical factor associated with vertical bone resorption (p = .000). The GV gradually increased during the follow-up period. CONCLUSIONS: Rapid and unavoidable peri-implant bone resorption usually happened during the first 6 months after implant placement. GBR is a predictable treatment for maxillary anterior implants, since GV has an increasing trend. Large bone particles of DBBM help maintain vertical alveolar bone stability.


Assuntos
Implantes Dentários , Maxila , Animais , Bovinos , Tomografia Computadorizada de Feixe Cônico , Estudos Transversais , Implantação Dentária Endóssea , Estética Dentária , Humanos , Estudos Retrospectivos
10.
J Neuroinflammation ; 16(1): 75, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30961627

RESUMO

BACKGROUND: Activation of microglial cells plays an important role in neuroinflammation after ischemic stroke. Inhibiting the activation of microglial cells has been suggested as a potential therapeutic approach in the treatment of ischemic stroke. METHODS: Oxygen-glucose deprivation in primary microglial cells and transient middle cerebral artery occlusion (MCAO) in C57BL/6 mice were used as the in vitro and in vivo ischemic stroke models. Microarray analysis was performed to investigate the overall impact of long non-coding RNAs (lncRNAs) on the inflammation status of microglial cells. RT-qPCR was used to evaluate the lncRNA levels and mRNA levels of cytokines and microglial cell markers. ELISA was taken to measure the level of cytokines. Immunofluorescence was used to observe the activation of microglial cells. Western blotting was performed to test the p65 phosphorylation. RESULTS: In this study, we showed that LncRNA-1810034E14Rik was significantly decreased in LPS-treated or oxygen-glucose deprivation-induced microglial cells. Overexpression of 1810034E14Rik decreased the infarct volume and alleviated brain damage in MCAO mice. 1810034E14Rik overexpression reduced the expression of inflammatory cytokines not only in ischemic stroke mice but also in oxygen-glucose deprivation-induced microglial cells. Moreover, 1810034E14Rik overexpression could suppress the activation of microglial cells and inhibit the phosphorylation of p65. CONCLUSIONS: LncRNA-1810034E14Rik plays an anti-inflammatory role in ischemic stroke and regulates p65 phosphorylation, making it a potential target for stroke treatment.


Assuntos
Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Microglia/metabolismo , Fosfoproteínas Fosfatases/metabolismo , RNA Longo não Codificante/metabolismo , Fator de Transcrição RelA/metabolismo , Animais , Animais Recém-Nascidos , Hipóxia Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Glucose/deficiência , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Análise em Microsséries , Microglia/efeitos dos fármacos , Fosfoproteínas Fosfatases/genética , RNA Longo não Codificante/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia
11.
Retina ; 39(6): 1091-1099, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29517579

RESUMO

PURPOSE: To elucidate the development of the choroid and retina in children, and to explore changes in these during myopic shift. METHODS: A total of 118 children aged 7 to 12 years participated in this 1-year longitudinal study. Children underwent several examinations at baseline and follow-up, including cycloplegic refraction, axial length measurement, and swept-source optical coherence tomography. Thickness changes in the choroid and retina were compared among children with or without myopic shift. RESULTS: Eighty-eight children (74.6%) developed a myopic shift after 1 year, and their central foveal choroid was significantly attenuated (P < 0.01). No significant change was observed in choroids of children without myopic shift (P = 0.83). Choroidal thickness decreased in all subfields during myopic shift, whereas the thickness of the retinal layers increased or were unchanged in most subfields. Axial length increase and central foveal choroidal thinning were associated with myopic shift (R = 0.157, P < 0.01), but axial length increase was not significantly related to choroidal thinning (P > 0.05). CONCLUSION: Choroidal thinning occurs early in myopic progression. Axial length increase and choroidal thinning are independently associated with myopic shift.


Assuntos
Corioide/patologia , Miopia/diagnóstico , Refração Ocular , Retina/patologia , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Comprimento Axial do Olho , Criança , Progressão da Doença , Feminino , Seguimentos , Humanos , Pressão Intraocular/fisiologia , Masculino , Miopia/fisiopatologia , Estudos Retrospectivos
12.
Cell Mol Neurobiol ; 38(3): 641-655, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28667374

RESUMO

Spinocerebellar ataxia 3 (SCA3), which is a progressive neurodegenerative disease, is currently incurable. Emerging studies have reported that human umbilical cord mesenchymal stem cells (HUC-MSCs) transplantation could be a promising therapeutic strategy for cerebellar ataxias. However, few studies have evaluated the effects of HUC-MSCs on SCA3 transgenic mouse. Thus, we investigated the effects of HUC-MSCs on SCA3 mice and the underlying mechanisms in this study. SCA3 transgenic mice received systematic administration of 2 × 106 HUC-MSCs once per week for 12 continuous weeks. Motor coordination was measured blindly by open field tests and footprint tests. Immunohistochemistry and Nissl staining were applied to detect neuropathological alternations. Neurotrophic factors in the cerebellum were assessed by ELISA. We used western blotting to detect the alternations of heat shock protein 70 (HSP70), IGF-1, mutant ataxin-3, and apoptosis-associated proteins. Tunel staining was also used to detect apoptosis of affected cells. The distribution and differentiation of HUC-MSCs were determined by immunofluorescence. Our results exhibited that HUC-MSCs transplantation significantly alleviated motor impairments, corresponding to a reduction of cerebellar atrophy, preservation of neurons, decreased expression of mutant ataxin-3, and increased expression of HSP70. Implanted HUC-MSCs were mainly distributed in the cerebellum and pons with no obvious differentiation, and the expressions of IGF-1, VEGF, and NGF in the cerebellum were significantly elevated. Furthermore, with the use of HSP70 analogy quercetin injection, it demonstrated that HSP70 is involved in mutant ataxin-3 reduction. These results showed that HUC-MSCs implantation is a potential treatment for SCA3, likely through upregulating the IGF-1/HSP70 pathway and subsequently inhibiting mutant ataxin-3 toxicity.


Assuntos
Ataxina-3/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Cordão Umbilical/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos Transgênicos , Fatores de Crescimento Neural/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Substâncias Protetoras/farmacologia , Cordão Umbilical/citologia
13.
Ecotoxicol Environ Saf ; 147: 699-707, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28938140

RESUMO

The aim of this work was to study the removal of Cu (II) and U (VI) ions from aqueous solutions by encapsulating magnetic Fe3O4 nanoparticles into calcium alginate coated chitosan hydrochloride (CCM) hydrogel beads. ATR-FTIR and XRD analysis data indicated that the CCM composites were successfully prepared. SEM images and EDX spectra showed that Cu2+ and UO22+ ions were adhered onto sorbents. Adsorption properties for removal of both copper and uranium ions under various experimental conditions were investigated. Kinetic data and sorption equilibrium isotherms were also conducted in batch process. The sorption kinetic analysis revealed that sorption of Cu (II) and U (VI) followed the pseudo-second-order model well and exhibited 3-stage intraparticle diffusion model during the whole sorption process. Equilibrium data were best described by Langmuir model, and the CCM composite hydrogel beads showed the estimated maximum adsorption capacity 143.276mg/g and 392.692mg/g for Cu (II) and U (VI), respectively. The CCM adsorbent exhibited excellent reusability for five cycles use without significant changes in the adsorption capacity and structural stability. The results demonstrated that CCM can be an effective and promising sorbent for Cu (II) and U (VI) ions in wastewater.


Assuntos
Alginatos/química , Quitosana/química , Cobre/análise , Nanopartículas de Magnetita/química , Compostos de Urânio/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Hidrogéis/química , Concentração de Íons de Hidrogênio , Íons , Cinética , Modelos Teóricos , Soluções
14.
Fish Shellfish Immunol ; 63: 444-451, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28235639

RESUMO

High concentration of ammonia in aquatic system leads to detrimental effects on the health of aquatic animals. However, the mechanism underlying ammonia-induced toxicity is still not clear. To better understand the mechanism of ammonia toxicity effects on fish, juvenile grass carp was employed in the present study. RNA high-throughput sequencing technique was applied to analyze the total RNAs extracted from the liver of fish after 8 h post exposure to the water containing 2 mM NH4HCO3 which experimentally mimicked the high environmental ammonia (HEA). A total of 49,971,114 and 53,826,986 clean reads were obtained in control and 2 mM HEA group, respectively, in which there were 911 differently expressed genes (DEGs) including 563 up-regulated and 348 down-regulated genes. In addition, 10 DEGs were validated by quantitative PCR. These DEGs were involved in several pathways related with oxidative stress or apoptosis. Further analysis on oxidative stress, histopathology and cellular apoptosis in grass carp liver after HEA exposure revealed interesting findings. Increased reactive oxygen species (ROS) content and superoxide dismutase (SOD) activity together with the decreased catalase (CAT) activity were detected, which may be effected by DEGs and related pathways such as FOXO signaling pathway. The histopathology and TUNEL assays results confirmed that apoptosis was induced in liver when fish had suffered HEA. Combined with the results of transcriptomic experiments, c-Myc-Bax-Caspase9 apoptosis pathway could be involved in grass carp liver apoptosis induced by ammonia stress.


Assuntos
Amônia/toxicidade , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Carpas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Transcriptoma , Poluentes Químicos da Água/toxicidade , Amônia/metabolismo , Animais , Perfilação da Expressão Gênica/veterinária , Inativação Metabólica , Fígado/efeitos dos fármacos , Fígado/metabolismo , Transdução de Sinais/efeitos dos fármacos , Poluentes Químicos da Água/metabolismo
15.
Retina ; 37(2): 368-375, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27429378

RESUMO

PURPOSE: To explore the characteristics of choroidal thickness (ChT) in Chinese children. METHODS: A total of 144 healthy children, aged 6 years to 12 years old, were enrolled in the study. The ChT of subfovea and peripheral locations 0.5, 1.5, and 2.5 mm away from the fovea were evaluated by enhanced depth imaging optical coherence tomography. The association between subfoveal ChT and systemic, as well as ocular factors, including age, sex, height, weight, body mass index, axial length, refractive error, intraocular pressure, preterm history, and the refractive status of parents were studied. RESULTS: The mean subfoveal ChT was 302 ± 63 µm. In the nasal, superior, and inferior areas, the ChT of locations closer to the fovea was thicker than those farther away from the fovea (all P < 0.05); however, ChT was not significantly different among different locations in the temporal area (P = 0.16). The ChT of the nasal quadrant was significantly thinner than that of other areas (P < 0.01). Subfoveal ChT decreased with age, axial length, preterm history, and increased with height. Sex was not statistically associated with subfoveal ChT. CONCLUSION: In Chinese children, the ChT is thinnest in the nasal quadrant and thicker in central regions than in peripheral areas. The subfoveal ChT independently decreases with age, axial length, preterm history, and increases with height.


Assuntos
Povo Asiático , Corioide/anatomia & histologia , Fatores Etários , Comprimento Axial do Olho/fisiologia , Estatura , Peso Corporal , Criança , China , Estudos Transversais , Feminino , Humanos , Masculino , Tamanho do Órgão , Erros de Refração/patologia , Tomografia de Coerência Óptica/métodos
16.
J Neuroinflammation ; 12: 51, 2015 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-25889216

RESUMO

BACKGROUND: Activation of microglia plays a crucial role in immune and inflammatory processes after ischemic stroke. Microglia is reported with two opposing activated phenotypes, namely, classic phenotype (M1) and the alternative phenotype (M2). Inhibiting M1 while stimulating M2 has been suggested as a potential therapeutic approach in the treatment of stroke. FINDINGS: In this study, we indicated that a novel natural anti-oxidant extracted from the Chinese plant Hopea hainanensis, malibatol A (MA), decreased the infarct size and alleviated the brain injury after mice middle cerebral artery occlusion (MCAO). MA inhibited expression inflammatory cytokines in not only MCAO mice but also lipopolysaccharide (LPS)-stimulated microglia. Moreover, treatment of MA decreased M1 markers (CD16, CD32, and CD86) and increased M2 markers (CD206, YM-1) while promoting the activation of nuclear receptor PPARγ. CONCLUSIONS: MA has anti-inflammatory effects in MCAO mice in a PPARγ-dependent manner, making it a potential candidate for stroke treatment.


Assuntos
Polaridade Celular/efeitos dos fármacos , Infarto da Artéria Cerebral Média/patologia , Microglia/efeitos dos fármacos , PPAR gama/metabolismo , Estilbenos/farmacologia , Estilbenos/uso terapêutico , Animais , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Infarto Encefálico/etiologia , Infarto Encefálico/prevenção & controle , Proteínas de Ligação ao Cálcio/metabolismo , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , Lipopolissacarídeos/farmacologia , Camundongos , Proteínas dos Microfilamentos/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Óxido Nítrico Sintase Tipo II/metabolismo , PPAR gama/antagonistas & inibidores , Piridinas/farmacologia , Piridinas/uso terapêutico , Fatores de Tempo
17.
Int J Neuropsychopharmacol ; 17(9): 1511-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24641999

RESUMO

ß-amyloid (Aß)-mediated neuronal apoptosis contributes to the progression of Alzheimer's disease (AD), although the exact mechanism remains unclear. This study aimed to investigate whether Dalesconol B (TL-2), a potent immunosuppressive agent with an unusual carbon skeleton, could inhibit Aß-induced apoptosis in vitro and in vivo and to explore the underlying mechanisms. Aß(1-42) was injected to bilateral hippocampus of mice to make the AD models in vivo. TL-2 was able to cross the blood-brain barrier and attenuate memory deficits in the AD mice. TL-2 also inhibited Aß(1-42)-induced neuronal apoptosis in vitro and in vivo. In addition, TL-2 could activate the AKT/GSK-3ß pathway, and inhibition of AKT and activation of GSK-3ß partially eliminated the neuroprotective effects of TL-2. Furthermore, TL-2 induced the nuclear translocation of ß-catenin and enhanced its transcriptional activity through the AKT/GSK-3ß pathway to promote neuronal survival. These results suggest that TL-2 might be a potential drug for AD treatment.


Assuntos
Doença de Alzheimer , Apoptose/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Hidrocarbonetos Policíclicos Aromáticos/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/complicações , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/toxicidade , Animais , Caspase 3/metabolismo , Caspase 9/metabolismo , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/patologia , Cromonas/farmacologia , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Camundongos , Morfolinas/farmacologia , Proteína Oncogênica v-akt/metabolismo , Fragmentos de Peptídeos/toxicidade , beta Catenina/metabolismo
18.
Clin Lab ; 60(2): 241-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24660536

RESUMO

BACKGROUND: A number of automated devices for pretransfusion testing have recently become available. This study evaluated the Immucor Galileo System, a fully automated device based on the microplate hemagglutination technique for ABO/Rh (D) determinations. METHODS: Routine ABO/Rh typing tests were performed on 13,045 samples using the Immucor automated instruments. Manual tube method was used to resolve ABO forward and reverse grouping discrepancies. D-negative test results were investigated and confirmed manually by the indirect antiglobulin test (IAT). RESULTS: The system rejected 70 tests for sample inadequacy. 87 samples were read as "No-type-determined" due to forward and reverse grouping discrepancies. 25 tests gave these results because of sample hemolysis. After further tests, we found 34 tests were caused by weakened RBC antibodies, 5 tests were attributable to weak A and/or B antigens, 4 tests were due to mixed-field reactions, and 8 tests had high titer cold agglutinin with blood qualifications which react only at temperatures below 34 degrees C. In the remaining 11 cases, irregular RBC antibodies were identified in 9 samples (seven anti-M and two anti-P) and two subgroups were identified in 2 samples (one A1 and one A2) by a reference laboratory. As for D typing, 2 weak D+ samples missed by automated systems gave negative results, but weak-positive reactions were observed in the IAT. CONCLUSIONS: The Immucor Galileo System is reliable and suited for ABO and D blood groups, some reasons may cause a discrepancy in ABO/D typing using a fully automated system. It is suggested that standardization of sample collection may improve the performance of the fully automated system.


Assuntos
Sistema ABO de Grupos Sanguíneos/classificação , Automação/métodos , Tipagem e Reações Cruzadas Sanguíneas/instrumentação , Tipagem e Reações Cruzadas Sanguíneas/métodos , Kit de Reagentes para Diagnóstico , Sistema do Grupo Sanguíneo Rh-Hr/classificação , Adulto , Automação/instrumentação , Humanos
19.
Int Immunopharmacol ; 129: 111648, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38335656

RESUMO

AIMS: To study the role of Aucubin (AU) in cerebral ischemia-reperfusion injury and investigate the potential mechanisms. METHODS: For the in vitro experiment, primary microglia were cultured and stimulated by Lipopolysaccharides (LPS) and treated with AU. Male C57/BL6J mice were used and middle cerebral artery occlusion (MCAO) model was performed to induce cerebral ischemia-reperfusion injury. For the short-term effects, mice administrated with AU (40 mg/kg) for 3 days after MCAO were evaluated for the infarct volume and neurological deficits. The neuroinflammatory factors and microglia activation were determined by Real-time PCR, western blot and immunofluorescence staining. For the long-term effects, MCAO mice were injected daily with AU (5 mg/kg or 10 mg/kg) for 28 days. Behavior tests were used to assess the neurological deficits of MCAO mice, and white matter integrity was determined by myelin basic protein (MBP) staining and black-gold staining. RESULTS: AU suppressed LPS-induced activation of microglia and pro-inflammatory cytokines release, and downregulated the NF-κB and MAPK pathways in primary microglia. In addition, AU attenuated ischemic injury and inhibited the neuro-inflammatory response in MCAO mice. Moreover, AU induced prolonged improvements in sensorimotor function and memory function following MCAO, and preserved white matter integrity in the long-term experiments. CONCLUSIONS: AU protected against ischemic injury, which might be correlated with the downregulation of NF-κB and MAPK signaling pathways. Furthermore, AU alleviated cognitive impairment after stroke and restored white matter integrity. Our data indicated that AU might be a potential compound for the treatment of stroke and post-stroke cognitive impairment.


Assuntos
Isquemia Encefálica , Glucosídeos Iridoides , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Camundongos , Masculino , Animais , NF-kappa B/metabolismo , Fármacos Neuroprotetores/farmacologia , Lipopolissacarídeos/farmacologia , Acidente Vascular Cerebral/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , Microglia , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo
20.
Adv Sci (Weinh) ; 11(12): e2301164, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38229144

RESUMO

Mechanistic target of rapamycin complex 1 (mTORC1) is a conserved serine/threonine kinase that integrates various environmental signals to regulate cell growth and metabolism. mTORC1 activation requires tethering to lysosomes by the Ragulator-Rag complex. However, the dynamic regulation of the interaction between Ragulator and Rag guanosine triphosphatase (GTPase) remains unclear. In this study, that LAMTOR1, an essential component of Ragulator, is dynamically ubiquitinated depending on amino acid abundance is reported. It is found that the E3 ligase TRAF4 directly interacts with LAMTOR1 and catalyzes the K63-linked polyubiquitination of LAMTOR1 at K151. Ubiquitination of LAMTOR1 by TRAF4 promoted its binding to Rag GTPases and enhanced mTORC1 activation, K151R knock-in or TRAF4 knock-out blocks amino acid-induced mTORC1 activation and accelerates the development of inflammation-induced colon cancer. This study revealed that TRAF4-mediated LAMTOR1 ubiquitination is a regulatory mechanism for mTORC1 activation and provides a therapeutic target for diseases involving mTORC1 dysregulation.


Assuntos
Neoplasias Colorretais , Proteínas Monoméricas de Ligação ao GTP , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Proteínas Monoméricas de Ligação ao GTP/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Fator 4 Associado a Receptor de TNF/metabolismo , Ubiquitinação , Aminoácidos/metabolismo
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