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1.
Cell ; 141(6): 1042-55, 2010 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-20550938

RESUMO

The molecular understanding of autophagy has originated almost exclusively from yeast genetic studies. Little is known about essential autophagy components specific to higher eukaryotes. Here we perform genetic screens in C. elegans and identify four metazoan-specific autophagy genes, named epg-2, -3, -4, and -5. Genetic analysis reveals that epg-2, -3, -4, and -5 define discrete genetic steps of the autophagy pathway. epg-2 encodes a coiled-coil protein that functions in specific autophagic cargo recognition. Mammalian homologs of EPG-3/VMP1, EPG-4/EI24, and EPG-5/mEPG5 are essential for starvation-induced autophagy. VMP1 regulates autophagosome formation by controlling the duration of omegasomes. EI24 and mEPG5 are required for formation of degradative autolysosomes. This study establishes C. elegans as a multicellular genetic model to delineate the autophagy pathway and provides mechanistic insights into the metazoan-specific autophagic process.


Assuntos
Autofagia , Caenorhabditis elegans/genética , Animais , Caenorhabditis elegans/citologia , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans/genética , Grânulos Citoplasmáticos/metabolismo , Lisossomos/metabolismo , Mutação , Fagossomos/metabolismo
2.
Nature ; 574(7778): 372-377, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31619789

RESUMO

Diabetes is far more prevalent in smokers than non-smokers, but the underlying mechanisms of vulnerability are unknown. Here we show that the diabetes-associated gene Tcf7l2 is densely expressed in the medial habenula (mHb) region of the rodent brain, where it regulates the function of nicotinic acetylcholine receptors. Inhibition of TCF7L2 signalling in the mHb increases nicotine intake in mice and rats. Nicotine increases levels of blood glucose by TCF7L2-dependent stimulation of the mHb. Virus-tracing experiments identify a polysynaptic connection from the mHb to the pancreas, and wild-type rats with a history of nicotine consumption show increased circulating levels of glucagon and insulin, and diabetes-like dysregulation of blood glucose homeostasis. By contrast, mutant Tcf7l2 rats are resistant to these actions of nicotine. Our findings suggest that TCF7L2 regulates the stimulatory actions of nicotine on a habenula-pancreas axis that links the addictive properties of nicotine to its diabetes-promoting actions.


Assuntos
Transtornos do Metabolismo de Glucose/genética , Habenula/metabolismo , Transdução de Sinais , Tabagismo/complicações , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Animais , AMP Cíclico/metabolismo , Glucose/metabolismo , Transtornos do Metabolismo de Glucose/metabolismo , Humanos , Camundongos , Mutagênese , Nicotina/metabolismo , Células PC12 , Pâncreas/metabolismo , Ratos , Receptores Nicotínicos/metabolismo , Tabagismo/genética , Tabagismo/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética
3.
Neurochem Res ; 49(2): 519-531, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37962706

RESUMO

In recent years, the decline of microglia in the hippocampus has been shown to play a role in the development of depression, and its reversal shows marked antidepressant-like effects. ß-glucan is a polysaccharide from Saccharomyces cerevisiae and has numerous beneficial effects on the nervous system, including improving axon regeneration and cognition. Considering its immuno-stimulatory activities in cultured microglia and brain tissues, we hypothesize that ß-glucan may be a potential candidate to correct the functional deficiency of microglia and thereby alleviate depression-like behaviors in chronically stressed animals. An expected, our results showed that a single injection of ß-glucan 5 h before behavioral tests at a dose of 10 or 20 mg/kg, but not at a dose of 5 mg/kg, reversed the depression-like behavior induced by chronic stress in mice in the tail suspension test, forced swimming test, and sucrose preference test. The effect of ß-glucan (20 mg/kg) also showed time-dependent properties that were statistically significant 5 and 8, but not 3, hours after drug injection and persisted for at least 7 days. Fourteen days after ß-glucan injection, no antidepressant-like effect was observed anymore. However, this effect was overcome by a second ß-glucan injection (20 mg/kg) 14 days after the first ß-glucan injection. Stimulation of microglia appeared to mediate the antidepressant-like effect of ß-glucan, because both inhibition of microglia and their depletion prevented the antidepressant-like effect of ß-glucan. Based on these effects of ß-glucan, ß-glucan administration could be developed as a new strategy for the treatment of depression.


Assuntos
Depressão , beta-Glucanas , Animais , Camundongos , Depressão/tratamento farmacológico , Depressão/etiologia , Microglia , beta-Glucanas/farmacologia , beta-Glucanas/uso terapêutico , Axônios , Regeneração Nervosa , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Hipocampo , Estresse Psicológico/tratamento farmacológico , Modelos Animais de Doenças
4.
Environ Sci Technol ; 58(18): 7743-7757, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38652822

RESUMO

Permeabilities of various trace elements (TEs) through the blood-follicle barrier (BFB) play an important role in oocyte development. However, it has not been comprehensively described as well as its involved biological pathways. Our study aimed to construct a blood-follicle distribution model of the concerned TEs and explore their related biological pathways. We finally included a total of 168 women from a cohort of in vitro fertilization-embryo transfer conducted in two reproductive centers in Beijing City and Shandong Province, China. The concentrations of 35 TEs in both serum and follicular fluid (FF) samples from the 168 women were measured, as well as the multiomics features of the metabolome, lipidome, and proteome in both plasma and FF samples. Multiomics features associated with the transfer efficiencies of TEs through the BFB were selected by using an elastic net model and further utilized for pathway analysis. Various machine learning (ML) models were built to predict the concentrations of TEs in FF. Overall, there are 21 TEs that exhibited three types of consistent BFB distribution characteristics between Beijing and Shandong centers. Among them, the concentrations of arsenic, manganese, nickel, tin, and bismuth in FF were higher than those in the serum with transfer efficiencies of 1.19-4.38, while a reverse trend was observed for the 15 TEs with transfer efficiencies of 0.076-0.905, e.g., mercury, germanium, selenium, antimony, and titanium. Lastly, cadmium was evenly distributed in the two compartments with transfer efficiencies of 0.998-1.056. Multiomics analysis showed that the enrichment of TEs was associated with the synthesis and action of steroid hormones and the glucose metabolism. Random forest model can provide the most accurate predictions of the concentrations of TEs in FF among the concerned ML models. In conclusion, the selective permeability through the BFB for various TEs may be significantly regulated by the steroid hormones and the glucose metabolism. Also, the concentrations of some TEs in FF can be well predicted by their serum levels with a random forest model.


Assuntos
Aprendizado de Máquina , Oligoelementos , Humanos , Oligoelementos/metabolismo , Feminino , Líquido Folicular/metabolismo , Líquido Folicular/química , China , Multiômica
5.
J Cell Sci ; 134(7)2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33674450

RESUMO

The small Rho-family GTPase Cdc42 has long been known to have a role in cell motility and axon growth. The eukaryotic Ccd42 gene is alternatively spliced to generate mRNAs with two different 3' untranslated regions (UTRs) that encode proteins with distinct C-termini. The C-termini of these Cdc42 proteins include CaaX and CCaX motifs for post-translational prenylation and palmitoylation, respectively. Palmitoyl-Cdc42 protein was previously shown to contribute to dendrite maturation, while the prenyl-Cdc42 protein contributes to axon specification and its mRNA was detected in neurites. Here, we show that the mRNA encoding prenyl-Cdc42 isoform preferentially localizes into PNS axons and this localization selectively increases in vivo during peripheral nervous system (PNS) axon regeneration. Functional studies indicate that prenyl-Cdc42 increases axon length in a manner that requires axonal targeting of its mRNA, which, in turn, needs an intact C-terminal CaaX motif that can drive prenylation of the encoded protein. In contrast, palmitoyl-Cdc42 has no effect on axon growth but selectively increases dendrite length. Together, these data show that alternative splicing of the Cdc42 gene product generates an axon growth promoting, locally synthesized prenyl-Cdc42 protein. This article has an associated First Person interview with one of the co-first authors of the paper.


Assuntos
Axônios , Isoformas de RNA , Axônios/metabolismo , Lipoilação , Regeneração Nervosa , Isoformas de RNA/metabolismo , Proteína cdc42 de Ligação ao GTP/genética , Proteína cdc42 de Ligação ao GTP/metabolismo
6.
Am J Physiol Heart Circ Physiol ; 324(4): H528-H541, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36867446

RESUMO

Takotsubo syndrome (TTS) is characterized by short-term contractile dysfunction with its mechanism undefined. We showed that activation of cardiac Hippo pathway mediates mitochondrial dysfunction and that stimulation of ß-adrenoceptors (ßAR) activates Hippo pathway. Here, we investigated the role of ßAR-Hippo signaling in mediating mitochondrial dysfunction in isoproterenol (Iso)-induced TTS-like mouse model. Elderly postmenopausal female mice were administered with Iso (1.25 mg/kg/h for 23 h). Cardiac function was determined by serially echocardiography. At days 1 and 7 post-Iso exposure, mitochondrial ultrastructure and function were examined by electron microscopy and various assays. Alterations in cardiac Hippo pathway and effects of genetic inactivation of Hippo kinase (Mst1) on mitochondrial damage and dysfunction in the acute phase of TTS were investigated. Isoproterenol exposure induced acute increase in biomarkers of cardiac damage and ventricular contractile dysfunction and dilation. At day 1 post-Iso, we observed extensive abnormalities in mitochondrial ultrastructure, downregulation of mitochondrial marker proteins, and mitochondrial dysfunction evidenced by lower ATP content, increased lipid droplets, higher contents of lactate, and augmented reactive oxygen species (ROS). All changes were reversed by day 7. ßAR stimulation led to activation of cardiac Hippo pathway with enhanced expression of Hippo kinase Mst1 and inhibitory YAP phosphorylation, as well as reduced nuclear YAP-TEAD1 interaction. In mice with cardiac expression of inactive mutant Mst1 gene, acute mitochondrial damage and dysfunction were mitigated. Stimulation of cardiac ßAR activates Hippo pathway that mediates mitochondrial dysfunction with energy insufficiency and enhanced ROS, promoting acute but short-term ventricular dysfunction.NEW & NOTEWORTHY Takotsubo syndrome (TTS) is featured by activation of sympatho-ß-adrenoceptor (ßAR) system leading to acute loss of ventricular contractile performance. However, the molecular mechanism remains undefined. We demonstrated, in an isoproterenol-induced murine TTS-like model, extensive mitochondrial damage, metabolic dysfunction, and downregulated mitochondrial marker proteins, changes temporarily associated with cardiac dysfunction. Mechanistically, stimulation of ßAR activated Hippo signaling pathway and genetic inactivation of Mst1 kinase ameliorated mitochondrial damage and metabolic dysfunction at the acute phase of TTS.


Assuntos
Via de Sinalização Hippo , Cardiomiopatia de Takotsubo , Feminino , Camundongos , Animais , Cardiomiopatia de Takotsubo/induzido quimicamente , Isoproterenol , Espécies Reativas de Oxigênio , Modelos Animais de Doenças , Receptores Adrenérgicos beta
7.
Neurochem Res ; 48(10): 3160-3176, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37358676

RESUMO

We and others have reported that systematic stimulation of the central innate immune system by a low dose of lipopolysaccharide (LPS) can improve depression-like behavior in chronically stressed animals. However, it is unclear whether similar stimulation by intranasal administration could improve depression-like behavior in animals. We investigated this question using monophosphoryl lipid A (MPL), a derivative of LPS that lacks the adverse effects of LPS but is still immuno-stimulatory. We found that a single intranasal administration of MPL at a dose of 10 or 20 µg/mouse, but not at a dose of 5 µg/mouse, ameliorated chronic unpredictable stress (CUS)-induced depression-like behavior in mice, as evidenced by the decrease in immobility time in tail suspension test and forced swimming test and the increase in sucrose intake in sucrose preference test. In the time-dependent analysis, the antidepressant-like effect of a single intranasal MPL administration (20 µg/mouse) was observed 5 and 8 h but not 3 h after drug administration and persisted for at least 7 days. Fourteen days after the first intranasal MPL administration, a second intranasal MPL administration (20 µg/mouse) still showed an antidepressant-like effect. The innate immune response mediated by microglia might mediate the antidepressant-like effect of intranasal MPL administration, because both inhibition of microglial activation by pretreatment with minocycline and depletion of microglia by pretreatment with PLX3397 prevented the antidepressant-like effect of intranasal MPL administration. These results suggest that intranasal administration of MPL can produce significant antidepressant-like effects in animals under chronic stress conditions via stimulation of microglia.


Assuntos
Depressão , Microglia , Animais , Camundongos , Depressão/tratamento farmacológico , Depressão/induzido quimicamente , Lipopolissacarídeos/toxicidade , Administração Intranasal , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Sacarose/farmacologia , Modelos Animais de Doenças , Hipocampo
9.
Acta Pharmacol Sin ; 44(5): 1051-1065, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36347997

RESUMO

Previous studies have shown mitochondrial dysfunction in various acute kidney injuries and chronic kidney diseases. Lipoic acid exerts potent effects on oxidant stress and modulation of mitochondrial function in damaged organ. In this study we investigated whether alpha lipoamide (ALM), a derivative of lipoic acid, exerted a renal protective effect in a type 2 diabetes mellitus mouse model. 9-week-old db/db mice were treated with ALM (50 mg·kg-1·d-1, i.g) for 8 weeks. We showed that ALM administration did not affect blood glucose levels in db/db mice, but restored renal function and significantly improved fibrosis of kidneys. We demonstrated that ALM administration significantly ameliorated mitochondrial dysfunction and tubulointerstitial fibrotic lesions, along with increased expression of CDX2 and CFTR and decreased expression of ß-catenin and Snail in kidneys of db/db mice. Similar protective effects were observed in rat renal tubular epithelial cell line NRK-52E cultured in high-glucose medium following treatment with ALM (200 µM). The protective mechanisms of ALM in diabetic kidney disease (DKD) were further explored: Autodock Vina software predicted that ALM could activate RXRα protein by forming stable hydrogen bonds. PROMO Database predicted that RXRα could bind the promoter sequences of CDX2 gene. Knockdown of RXRα expression in NRK-52E cells under normal glucose condition suppressed CDX2 expression and promoted phenotypic changes in renal tubular epithelial cells. However, RXRα overexpression increased CDX2 expression which in turn inhibited high glucose-mediated renal tubular epithelial cell injury. Therefore, we reveal the protective effect of ALM on DKD and its possible potential targets: ALM ameliorates mitochondrial dysfunction and regulates the CDX2/CFTR/ß-catenin signaling axis through upregulation and activation of RXRα. Schematic figure illustrating that ALM alleviates diabetic kidney disease by improving mitochondrial function and upregulation and activation of RXRα, which in turn upregulated CDX2 to exert an inhibitory effect on ß-catenin activation and nuclear translocation. RTEC renal tubular epithelial cell. ROS Reactive oxygen species. RXRα Retinoid X receptor-α. Mfn1 Mitofusin 1. Drp1 dynamic-related protein 1. MDA malondialdehyde. 4-HNE 4-hydroxynonenal. T-SOD Total-superoxide dismutase. CDX2 Caudal-type homeobox transcription factor 2. CFTR Cystic fibrosis transmembrane conductance regulator. EMT epithelial mesenchymal transition. α-SMA Alpha-smooth muscle actin. ECM extracellular matrix. DKD diabetic kidney disease. Schematic figure was drawn by Figdraw ( www.figdraw.com ).


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Ácido Tióctico , Animais , Camundongos , Ratos , beta Catenina/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/patologia , Transição Epitelial-Mesenquimal , Fibrose/tratamento farmacológico , Fibrose/metabolismo , Glucose/metabolismo , Rim/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Ácido Tióctico/farmacologia , Ácido Tióctico/uso terapêutico , Receptor X Retinoide alfa/efeitos dos fármacos , Receptor X Retinoide alfa/metabolismo
10.
Transfus Apher Sci ; 62(4): 103716, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37147249

RESUMO

Intravenous immune globulin (IVIG) is a common treatment given after plasma exchange procedures to either prevent secondary hypogammaglobulinemia or as an adjunctive treatment for organ transplant rejection. However, side-effects are relatively common with this medication during and after infusion. This case-report describes our alternative to IVIG infusions post-plasma exchange. We hypothesize that in patients unable to tolerate IVIG, using thawed plasma as a replacement fluid provides a suitable increase in the patients post procedure immunoglobulin G (IgG) levels for patients with secondary hypogammaglobulinemia that are unable to tolerate IVIG infusions.


Assuntos
Agamaglobulinemia , Imunoglobulinas Intravenosas , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Imunoglobulina G , Agamaglobulinemia/prevenção & controle , Troca Plasmática
11.
J Clin Apher ; 38(6): 755-759, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37665037

RESUMO

This manuscript describes a novel approach for treating patients with long-term sequelae from hemoglobin Evans (Hb Evans). After instituting conservative therapies for approximately 2 years, our patient's symptoms continually worsened. Therefore, we performed red blood cell exchange (RBCx) to reduce his Hb Evans percentage and his co-existing elevation of methemoglobin. Our assumptions of clinical benefit were based on our collective experience performing RBCx for patients with sickle cell disease. After the first exchange, pre- and post-laboratory results supported our approach and the patient experienced marked improvement in his clinical signs and symptoms. This report provides preliminary proof of principle for the use of RBCx to treat Hb Evans and other non-Hb S hemoglobinopathies.


Assuntos
Anemia Falciforme , Hemoglobinas Anormais , Metemoglobinemia , Humanos , Metemoglobinemia/terapia , Eritrócitos , Anemia Falciforme/complicações , Anemia Falciforme/terapia
12.
J Neurosci ; 41(8): 1779-1787, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33380469

RESUMO

Allelic variation in CHRNA3, the gene encoding the α3 nicotinic acetylcholine receptor (nAChR) subunit, increases vulnerability to tobacco dependence and smoking-related diseases, but little is known about the role for α3-containing (α3*) nAChRs in regulating the addiction-related behavioral or physiological actions of nicotine. α3* nAChRs are densely expressed by medial habenula (mHb) neurons, which project almost exclusively to the interpeduncular nucleus (IPn) and are known to regulate nicotine avoidance behaviors. We found that Chrna3tm1.1Hwrt hypomorphic mice, which express constitutively low levels of α3* nAChRs, self-administer greater quantities of nicotine (0.4 mg kg-1 per infusion) than their wild-type littermates. Microinfusion of a lentivirus vector to express a short-hairpin RNA into the mHb or IPn to knock-down Chrna3 transcripts markedly increased nicotine self-administration behavior in rats (0.01-0.18 mg kg-1 per infusion). Using whole-cell recordings, we found that the α3ß4* nAChR-selective antagonist α-conotoxin AuIB almost completely abolished nicotine-evoked currents in mHb neurons. By contrast, the α3ß2* nAChR-selective antagonist α-conotoxin MII only partially attenuated these currents. Finally, micro-infusion of α-conotoxin AuIB (10 µm) but not α-conotoxin MII (10 µm) into the IPn in rats increased nicotine self-administration behavior. Together, these data suggest that α3ß4* nAChRs regulate the stimulatory effects of nicotine on the mHb-IPn circuit and thereby regulate nicotine avoidance behaviors. These findings provide mechanistic insights into how CHRNA3 risk alleles can increase the risk of tobacco dependence and smoking-related diseases in human smokers.SIGNIFICANCE STATEMENT Allelic variation in CHRNA3, which encodes the α3 nicotinic acetylcholine receptor (nAChR) subunit gene, increases risk of tobacco dependence but underlying mechanisms are unclear. We report that Chrna3 hypomorphic mice consume greater quantities of nicotine than wild-type mice and that knock-down of Chrna3 gene transcripts in the habenula or interpeduncular nucleus (IPn) increases nicotine intake in rats. α-Conotoxin AuIB, a potent antagonist of the α3ß4 nAChR subtype, reduced the stimulatory effects of nicotine on habenular neurons, and its infusion into the IPn increased nicotine intake in rats. These data suggest that α3ß4 nAChRs in the habenula-IPn circuit regulate the motivational properties of nicotine.


Assuntos
Habenula/metabolismo , Núcleo Interpeduncular/metabolismo , Receptores Nicotínicos/metabolismo , Tabagismo/metabolismo , Animais , Feminino , Predisposição Genética para Doença/genética , Variação Genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Ratos Wistar , Receptores Nicotínicos/genética , Tabagismo/genética
13.
Exp Eye Res ; 222: 109152, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35714699

RESUMO

Diabetic retinopathy (DR) is a serious blinding complication of diabetes. At present, the therapeutic intervention effect is limited. We aimed to investigate the circRNA expression profiles in retinal proliferative fibrovascular membranes of patients with DR and explore the effect of circFAT1 on pyroptosis and autophagy of high glucose (HG)-induced retinal pigment epithelial (RPE) cells and its molecualr mechanism. In this study, circRNA sequencing was performed to determine the expression profiles of circRNAs in DR patients. The expression of circFAT1 was measured by qRT-PCR. Cell counting kit-8, transmission electron microscope, western blot, immunofluorescence and enzyme-linked immunosorbent assay were conducted to explore the roles of HG and circFAT1 in RPE cell pyroptosis and autophagy. RNA pull down was used to determine the binding protein of circFAT1. Our data showed that HG significantly reduced the viability of RPE cells, inhibited cell autophagy and contributed to cell pyroptosis. In addition, a total of 189 differentially expressed circRNAs (DEcircRNAs) were identified between DR patients and non-DR patients, including 93 upregulated and 96 downregulated DEcircRNAs in the retinal proliferative fibrovascular membranes of DR patients. Pathway analysis showed that DEcircRNAs were mainly involved in MAPK signaling pathway, TGF-beta signaling pathway and adherens junction. Moreover, circFAT1 was significantly downregulated in retinal proliferative fibrovascular membranes of DR patients and HG-induced RPE cells. CircFAT1 overexpression remarkably enhanced the expression of LC3B, while reduced the expression of GSDMD in HG-induced RPE cells. RNA pull down combined with western blot analysis indicated that circFAT1 bound to m6A reader YTHDF2. YTHDF2 overexpression significantly increased the protein expression of LC3B in HG-induced RPE cells. In summary, circFAT1 promoted autophagy and inhibited pyroptosis of RPE cells induced by HG, and could combine with YTHDF2. This study provides new ideas for DR prevention and treatment.


Assuntos
Caderinas/genética , Diabetes Mellitus , Retinopatia Diabética , Proteínas de Ligação a RNA/metabolismo , Autofagia , Caderinas/metabolismo , Linhagem Celular , Diabetes Mellitus/metabolismo , Retinopatia Diabética/genética , Retinopatia Diabética/metabolismo , Células Epiteliais/metabolismo , Glucose/metabolismo , Humanos , Piroptose , RNA/genética , RNA/metabolismo , RNA Circular/genética , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina/metabolismo , Pigmentos da Retina/farmacologia
14.
Brain Behav Immun ; 105: 44-66, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35781008

RESUMO

Our previous studies had reported that microglia activation one day before stress exposure prevented the behavioral abnormalities induced by chronic stress in adult mice, and a 10-day interval between microglia stimulation and stress exposure can abolish the prophylactic effect of LPS preinjection on the behavioral abnormalities induced by chronic stress, which, however, could be rescued by repeated LPS injection. This suggests that increased stimulation of microglia results in animals developing a strong ability to prevent deleterious stress stimuli. Because microglia in the adolescent brain exhibit flexible immunological plasticity, we hypothesize that a single low-dose LPS injection during adolescence may provide long-lasting protection against behavioral abnormalities induced by chronic stress in adult mice. As expected, our results showed that a single injection of LPS (100 µg/kg) at post-natal day 28 (PND 28) prevented the development of abnormal behaviors and shifted neuroinflammatory responses toward an anti-inflammatory phenotype in adult mice treated with CSDS at their different stages of the age (PND 56, 140, and 252). Moreover, pretreatment with minocycline or PLX3397 to inhibit microglial activation abolished the prophylactic effect of LPS preinjection after PND 28 on behavioral abnormalities and neuroinflammatory responses induced by CSDS in adult mice at their different stages of the age, PND 56, 140, and 252. These results indicate that stimulation of microglia in adolescence may confer long-lasting protection against neuroinflammatory responses and behavioral abnormalities induced by chronic stress in adult mice. This may offer the potential for the development of a "vaccine-like strategy" to prevent mental disorders.


Assuntos
Lipopolissacarídeos , Microglia , Animais , Anti-Inflamatórios/farmacologia , Encéfalo , Humanos , Inflamação/tratamento farmacológico , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Minociclina/farmacologia
15.
Brain Behav Immun ; 106: 147-160, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35995236

RESUMO

Depressed mice have lower numbers of microglia in the dentate gyrus (DG). Reversal of this decline by a single low dose of lipopolysaccharide (LPS) may have antidepressant effects, but there is little information on the molecular mechanisms underlying this effect. It is known that impairment of brain-derived neurotrophic factor (BDNF) signaling is involved in the development of depression. Here, we used a combination of neutralizing antibodies, mutant mice, and pharmacological approaches to test the role of BDNF-tyrosine kinase receptor B (TrkB) signaling in the DG in the effect of microglial stimulation. Our results suggest that inhibition of BDNF signaling by infusion of an anti-BDNF antibody, the BDNF receptor antagonist K252a, or knock-in of the mutant BDNF Val68Met allele abolished the antidepressant effect of LPS in chronically stressed mice. Increased BDNF synthesis in DG, mediated by extracellular signal-regulated kinase1/2 (ERK1/2) signaling but not protein kinase B (Akt)-mammalian target of rapamycin (mTOR) signaling, was essential for the antidepressant effect of microglial stimulation. These results suggest that increased BDNF synthesis through activation of ERK1/2 caused by a single LPS injection and subsequent TrkB signaling are required for the antidepressant effect of hippocampal microglial stimulation.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Receptor trkB , Animais , Anticorpos Neutralizantes/farmacologia , Antidepressivos/metabolismo , Antidepressivos/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipocampo/metabolismo , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases , Mamíferos/metabolismo , Camundongos , Microglia/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor trkB/metabolismo , Receptor trkB/farmacologia , Serina-Treonina Quinases TOR/metabolismo
16.
Am J Obstet Gynecol ; 227(5): 759.e1-759.e15, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35667419

RESUMO

BACKGROUND: It has been well recognized that antenatal administration of dexamethasone to pregnant women at risk of preterm delivery may markedly accelerate fetal maturation and reduce the risk of adverse perinatal outcomes in their preterm infants, particularly for births before 34 weeks of gestation. Since 2015, antenatal corticosteroid administration has been extended beyond 34 weeks of gestation by clinical guidelines, as it might have beneficial effects on fetal maturation and perinatal outcomes. However, concerns regarding the potential influence of antenatal corticosteroid treatment on offspring neurodevelopment have been raised. OBJECTIVE: This study aimed to investigate whether maternal antenatal corticosteroid administration was associated with neurodevelopment in infants at 1 year of age. STUDY DESIGN: In this prospective and longitudinal birth cohort study, women were followed up throughout gestation, and their infants underwent a Bayley Scales of Infant and Toddler Development, Third Edition, screening test at 1 year of age between December 2018 and September 2020. Finally, 1609 pregnant women and 1759 infants were included in the current study. Using a generalized linear mixed model, we examined the association between antenatal corticosteroid exposure and infant neurodevelopment in cognitive, receptive communication, expressive communication, fine motor, and gross motor functions. RESULTS: Of the 1759 infants eligible for this study, 1453 (82.6%) were singletons. A total of 710 infants were exposed to antenatal corticosteroids, among whom 415 were dexamethasone exposed and 483 were prednisone exposed. Dexamethasone was prescribed most often in late pregnancy, whereas prednisone was often used before 8 weeks of gestation among women who conceived through assisted reproductive technology. Compared with those who had no exposure, antenatal corticosteroid exposure was associated with an increased risk of infants being noncompetent in the cognitive development domain after adjusting for conventional risk factors (adjusted risk ratio, 1.53; 95% confidence interval, 1.08-2.18; P=.017). For medication-specific exposure, those exposed vs not exposed to antenatal dexamethasone were 1.62-fold (95% confidence interval, 1.10-2.38; P=.014) more likely to be noncompetent in the cognitive development domain at 1 year. The association did not vary markedly between preterm and term infants, singletons and twins, or assisted reproductive technology-conceived and spontaneously conceived infants (all P>.05 for heterogeneity). In contrast, a null association was observed for the risk of being noncompetent in any domain of neurodevelopment with antenatal prednisone exposure at early pregnancy. CONCLUSION: Here, antenatal corticosteroid, particularly dexamethasone exposure, was markedly associated with an increased risk of infants being noncompetent in the cognitive development domain at 1 year of age. These findings may provide new information when weighing the benefits and potential risks of maternal antenatal corticosteroid administration.


Assuntos
Recém-Nascido Prematuro , Nascimento Prematuro , Gravidez , Feminino , Lactente , Recém-Nascido , Humanos , Prednisona/uso terapêutico , Estudos de Coortes , Estudos Prospectivos , Corticosteroides/uso terapêutico , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/tratamento farmacológico , Dexametasona/efeitos adversos
17.
Nature ; 533(7601): 115-9, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-27096368

RESUMO

Defects in clearance of dying cells have been proposed to underlie the pathogenesis of systemic lupus erythematosus (SLE). Mice lacking molecules associated with dying cell clearance develop SLE-like disease, and phagocytes from patients with SLE often display defective clearance and increased inflammatory cytokine production when exposed to dying cells in vitro. Previously, we and others described a form of noncanonical autophagy known as LC3-associated phagocytosis (LAP), in which phagosomes containing engulfed particles, including dying cells, recruit elements of the autophagy pathway to facilitate maturation of phagosomes and digestion of their contents. Genome-wide association studies have identified polymorphisms in the Atg5 (ref. 8) and possibly Atg7 (ref. 9) genes, involved in both canonical autophagy and LAP, as markers of a predisposition for SLE. Here we describe the consequences of defective LAP in vivo. Mice lacking any of several components of the LAP pathway show increased serum levels of inflammatory cytokines and autoantibodies, glomerular immune complex deposition, and evidence of kidney damage. When dying cells are injected into LAP-deficient mice, they are engulfed but not efficiently degraded and trigger acute elevation of pro-inflammatory cytokines but not anti-inflammatory interleukin (IL)-10. Repeated injection of dying cells into LAP-deficient, but not LAP-sufficient, mice accelerated the development of SLE-like disease, including increased serum levels of autoantibodies. By contrast, mice deficient in genes required for canonical autophagy but not LAP do not display defective dying cell clearance, inflammatory cytokine production, or SLE-like disease, and, like wild-type mice, produce IL-10 in response to dying cells. Therefore, defects in LAP, rather than canonical autophagy, can cause SLE-like phenomena, and may contribute to the pathogenesis of SLE.


Assuntos
Autofagia , Inflamação/patologia , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Animais , Complexo Antígeno-Anticorpo/metabolismo , Autoanticorpos/sangue , Autofagia/genética , Citocinas/biossíntese , Citocinas/sangue , Inflamação/sangue , Inflamação/genética , Interleucina-10/biossíntese , Rim/metabolismo , Rim/patologia , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/genética , Masculino , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Fagócitos/citologia , Fagócitos/fisiologia , Fagossomos/fisiologia
18.
Environ Res ; 215(Pt 2): 114305, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096164

RESUMO

Previous epidemiological studies have reported that prenatal exposure to metals might have influence on fetal growth. Most studies assessed the effect of individual metals, while the investigation on the relationship between multiple metal exposure and fetal growth is sparse. The objective of the present study is to assess the joint impact of metal mixtures on fetal growth during pregnancy. A total of 1275 maternal-infant pairs from the Jiangsu Birth Cohort (JBC) Study were included to investigate the effect of maternal metal exposure on fetal biometry measures at 22-24, 30-32, and 34-36 weeks of gestation. Lead (Pb), arsenic (As), cadmium (Cd), mercury (Hg), chromium (Cr), vanadium(V), thallium (Tl) and barium (Ba) were measured by inductively coupled plasma mass spectrometry (ICP-MS) in maternal urine samples collected in the first trimester. We used general linear models and restricted cubic splines to test dose-response relationships between single metals and fetal growth. The weighted quantile sum (WQS) models were then applied to evaluate the overall effect of all these metals. We observed inverse associations of exposure to Pb, V and Cr with estimated fetal weight (EFW) at 34-36 weeks of gestation. Notably, maternal exposure to metal mixtures was significantly associated with reduced EFW at 34-36 weeks of gestation after adjusting for some covariates and confounders (aß -0.05 [95% CI: 0.09, -0.01], P = 0.023), and this association was mainly driven by Cr (30.41%), Pb (23.92%), and Tl (15.60%). These findings indicated that prenatal exposure to metal mixtures might impose adverse effects on fetal growth.


Assuntos
Arsênio , Mercúrio , Efeitos Tardios da Exposição Pré-Natal , Bário/farmacologia , Coorte de Nascimento , Cádmio , China , Cromo , Feminino , Desenvolvimento Fetal , Peso Fetal , Humanos , Chumbo , Exposição Materna , Gravidez , Tálio/farmacologia , Vanádio
19.
Age Ageing ; 51(1)2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34673897

RESUMO

BACKGROUND: Multiple myeloma is a disease of the older people, whose prognoses are highly heterogeneous. The International Myeloma Working Group (IMWG) proposed a geriatric assessment (GA) based on age, functional status and comorbidities to discriminate between fit and frail patients. Given the multidimensional nature of frailty and the relatively recent exploration of frailty in the field of MM, reaching a consensus on the measurement of frailty in MM patients remains challenging. OBJECTIVE: We sought to assess the feasibility of performing a comprehensive GA (CGA) in older MM patients in a real-world and multicentre setting and to evaluate their baseline CGA profiles. RESULTS: We studied 349 older patients with newly diagnosed MM (age range, 65-86 years). Our results showed that a CGA is feasible for older MM patients. Using the IMWG-GA criteria, we identified significantly more frail patients in our cohort comparing to in the IMWG cohort (43% vs 30%, P = 0.002). In the IMWG-GA 'fit' group, risk of malnutrition, depression and cognitive impairment remains. The median follow-up time was 26 months (range 1-38). The median overall survival (OS) was 34.7 months, and the estimated 3-year OS rate was 50%. A high MNA-SF score (MNA-SF ≥ 12), low GDS score (GDS ≤ 5) and high CCI score (CCI ≥ 2) can be used to predict the OS of older patients with newly diagnosed MM. This study is registered at www.clinicaltrials.gov (NCT03122327). CONCLUSIONS: Our study justifies the need for a CGA in older patients with newly diagnosed MM.


Assuntos
Fragilidade , Mieloma Múltiplo , Idoso , Idoso de 80 Anos ou mais , Idoso Fragilizado , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Avaliação Geriátrica , Humanos , Mieloma Múltiplo/diagnóstico , Estudos Prospectivos
20.
Pharmacology ; 107(9-10): 495-509, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35679828

RESUMO

INTRODUCTION: The increased migration of vascular smooth muscle cells (VSMCs) is an essential pathological factor in the early development of atherosclerosis. Beta-sitosterol (BS), a natural phytosterol abundant in plant seeds, exhibits various bioactivities, including cardioprotective effects. However, its effects on VSMC migration and underlying mechanisms remain to be explored. METHOD AND RESULT: BS inhibited the proliferation and migration of angiotensin II-induced A7r5 cells and reduced intracellular oxidative stress. Targets related to VSMC migration and the targets of BS were screened, cross-referenced, and analyzed by network pharmacology combined with molecular docking technology. The identified targets were verified at the protein and gene levels using Western blotting and quantitative PCR, respectively. BS was observed to activate peroxisome proliferator-activated receptor-γ (PPARG) and adenosine 5'-monophosphate-activated protein kinase (AMPK) and negatively regulate mammalian target of rapamycin (mTOR) expression. Furthermore, a PPARG inhibitor reversed the BS-induced activation of AMPK and mTOR. CONCLUSION: This study indicated that regulation of the PPARG/AMPK/mTOR signaling pathway could potentially contribute to the inhibitory effects of BS on angiotensin II-induced VSMC migration.


Assuntos
Músculo Liso Vascular , PPAR gama , Proteínas Quinases Ativadas por AMP/metabolismo , Angiotensina II/farmacologia , Movimento Celular , Proliferação de Células , Simulação de Acoplamento Molecular , Miócitos de Músculo Liso/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Sitosteroides , Serina-Treonina Quinases TOR/metabolismo
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