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1.
Cell ; 179(4): 864-879.e19, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31675497

RESUMO

Physical or mental stress leads to neuroplasticity in the brain and increases the risk of depression and anxiety. Stress exposure causes the dysfunction of peripheral T lymphocytes. However, the pathological role and underlying regulatory mechanism of peripheral T lymphocytes in mood disorders have not been well established. Here, we show that the lack of CD4+ T cells protects mice from stress-induced anxiety-like behavior. Physical stress-induced leukotriene B4 triggers severe mitochondrial fission in CD4+ T cells, which further leads to a variety of behavioral abnormalities including anxiety, depression, and social disorders. Metabolomic profiles and single-cell transcriptome reveal that CD4+ T cell-derived xanthine acts on oligodendrocytes in the left amygdala via adenosine receptor A1. Mitochondrial fission promotes the de novo synthesis of purine via interferon regulatory factor 1 accumulation in CD4+ T cells. Our study implicates a critical link between a purine metabolic disorder in CD4+ T cells and stress-driven anxiety-like behavior.


Assuntos
Ansiedade/metabolismo , Comportamento Animal/fisiologia , Encefalopatias Metabólicas/metabolismo , Estresse Psicológico/metabolismo , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/patologia , Animais , Ansiedade/genética , Ansiedade/imunologia , Ansiedade/fisiopatologia , Encefalopatias Metabólicas/genética , Encefalopatias Metabólicas/fisiopatologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Modelos Animais de Doenças , Humanos , Camundongos , Dinâmica Mitocondrial/genética , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Análise de Célula Única , Estresse Psicológico/genética , Estresse Psicológico/fisiopatologia , Transcriptoma/genética , Xantina/metabolismo
2.
EMBO Rep ; 24(1): e55387, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36394357

RESUMO

Interferon regulatory factor (IRF) 3 and IRF7 are master regulators of type I interferon (IFN-I)-dependent antiviral innate immunity. Upon viral infection, a positive feedback loop is formed, wherein IRF7 promotes further induction of IFN-I in the later stage. Thus, it is critical to maintain a suitably low level of IRF7 to avoid the hyperproduction of IFN-I. In this study, we find that early expression of IFN-I-dependent STAT1 promotes the expression of XAF1 and that XAF1 is associated specifically with IRF7 and inhibits the activity of XIAP. XAF1-knockout and XIAP-transgenic mice display resistance to viral infection, and this resistance is accompanied by increases in IFN-I production and IRF7 stability. Mechanistically, we find that the XAF1-XIAP axis controls the activity of KLHL22, an adaptor of the BTB-CUL3-RBX1 E3 ligase complex through a ubiquitin-dependent pathway. CUL3-KLHL22 directly targets IRF7 and catalyzes its K48-linked ubiquitination and proteasomal degradation. These findings reveal unexpected functions of the XAF1-XIAP axis and KLHL22 in the regulation of IRF7 stability and highlight an important target for antiviral innate immunity.


Assuntos
Interferon Tipo I , Viroses , Camundongos , Animais , Viroses/genética , Antivirais , Imunidade Inata , Ubiquitinação , Fator Regulador 7 de Interferon/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose
3.
Biochem Biophys Res Commun ; 734: 150662, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39245030

RESUMO

Lipid metabolism, particularly triglyceride (TG) metabolism, is crucial for liver regeneration. During the early phase of liver regeneration, the liver temporarily accumulates a substantial amount of TG-dominated lipids. However, the specific composition of the TG profile during this phase is not yet fully understood. Here, we showed that the TG molecular composition in the liver was significantly altered during liver regeneration following carbon tetrachloride (CCl4)-induced liver injury. Lipid accumulation in livers was observed as early as 12 hours after CCl4 treatment, with transient regeneration-associated steatosis (TRAS) lasting until 24 hours. Hepatocyte proliferation began only after liver lipid levels returned to baseline at 48 hours. Furthermore, the profile of TG species changed significantly during liver regeneration. During the TRAS period, the accumulated TGs in the liver were mainly long-chain triglycerides, with most of the fatty acids constituting these triglycerides having fewer than 20 carbon atoms. In the proliferation phase, the fatty acid composition of these triglycerides shifted from long-chain to ultra-long-chain fatty acids. Our results suggest a significant TRAS-related change in the TG lipid profile of the liver during liver regeneration.

4.
Acta Pharmacol Sin ; 45(10): 2119-2133, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38811775

RESUMO

Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to the epidermal growth factor precursor homologous domain A (EGF-A) of low-density lipoprotein receptor (LDLR) in the liver and triggers the degradation of LDLR via the lysosomal pathway, consequently leading to an elevation in plasma LDL-C levels. Inhibiting PCSK9 prolongs the lifespan of LDLR and maintains cholesterol homeostasis in the body. Thus, PCSK9 is an innovative pharmacological target for treating hypercholesterolemia and atherosclerosis. In this study, we discovered that E28362 was a novel small-molecule PCSK9 inhibitor by conducting a virtual screening of a library containing 40,000 compounds. E28362 (5, 10, 20 µM) dose-dependently increased the protein levels of LDLR in both total protein and the membrane fraction in both HepG2 and AML12 cells, and enhanced the uptake of DiI-LDL in AML12 cells. MTT assay showed that E28362 up to 80 µM had no obvious toxicity in HepG2, AML12, and HEK293a cells. The effects of E28362 on hyperlipidemia and atherosclerosis were evaluated in three different animal models. In high-fat diet-fed golden hamsters, administration of E28362 (6.7, 20, 60 mg·kg-1·d-1, i.g.) for 4 weeks significantly reduced plasma total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C) and PCSK9 levels, and reduced liver TC and TG contents. In Western diet-fed ApoE-/- mice (20, 60 mg·kg-1·d-1, i.g.) and human PCSK9 D374Y overexpression mice (60 mg·kg-1·d-1, i.g.), administration of E28362 for 12 weeks significantly decreased plasma LDL-C levels and the area of atherosclerotic lesions in en face aortas and aortic roots. Moreover, E28362 significantly increased the protein expression level of LDLR in the liver. We revealed that E28362 selectively bound to PCSK9 in HepG2 and AML12 cells, blocked the interaction between LDLR and PCSK9, and induced the degradation of PCSK9 through the ubiquitin-proteasome pathway, which finally resulted in increased LDLR protein levels. In conclusion, E28362 can block the interaction between PCSK9 and LDLR, induce the degradation of PCSK9, increase LDLR protein levels, and alleviate hyperlipidemia and atherosclerosis in three distinct animal models, suggesting that E28362 is a promising lead compound for the treatment of hyperlipidemia and atherosclerosis.


Assuntos
Aterosclerose , Hiperlipidemias , Inibidores de PCSK9 , Pró-Proteína Convertase 9 , Receptores de LDL , Animais , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Humanos , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/metabolismo , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/metabolismo , Masculino , Células Hep G2 , Camundongos , Células HEK293 , Camundongos Endogâmicos C57BL , Mesocricetus , Dieta Hiperlipídica , Cricetinae
5.
Molecules ; 28(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37959761

RESUMO

Cl, Br, and I are elements in the halogen family, and are often used as dopants in semiconductors. When employed as dopants, these halogens can significantly modify the optoelectronic properties of materials. From the perspective of halogen doping, we have successfully achieved the stabilization of crystal structures in CH3NH3PbX3, CH3NH3PbI3-xClx, CH3NH3PbI3-xBrx, and CH3NH3PbBr3-xClx, which are organic-inorganic hybrid perovskites. Utilizing first-principles density functional theory calculations with the CASTEP module, we investigated the optoelectronic properties of these structures by simulations. According to the calculations, a smaller difference in electronegativity between different halogens in doped structures can result in smoother energy bands, especially in CH3NH3PbI3-xBrx and CH3NH3PbBr3-xClx. The PDOS of the Cl-3p orbitals undergoes a shift along the energy axis as a result of variances in electronegativity levels. The optoelectronic performance, carrier mobility, and structural stability of the CH3NH3PbBr3-xClx system are superior to other systems like CH3NH3PbX3. Among many materials considered, CH3NH3PbBr2Cl exhibits higher carrier mobility and a relatively narrower bandgap, making it a more suitable material for the absorption layer in solar cells. This study provides valuable insights into the methodology employed for the selection of specific types, quantities, and positions of halogens for further research on halogen doping.

6.
Molecules ; 28(17)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37687114

RESUMO

The theory of electron spin has been proposed for a century, but the study of quantum effects in biological molecules is still in its infancy. Chirality-induced spin selectivity (CISS) is a very modern theory that can explain many biochemical phenomena. In this paper, we propose a new theoretical model based on CISS theory and quantum chemistry theory, which can well explain the theoretical explanation of the chiral selectivity of chiral proteins. Moreover, this theory can predict the spin state of corresponding chiral molecules. Taking the L-DOPA and AADC enzymes as examples, this theoretical model elucidates the AADC enzyme's chiral catalysis selectivity and successfully predicts the spin state of L-DOPA and D-DOPA's valence electrons.

7.
Angew Chem Int Ed Engl ; 61(22): e202202585, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35229423

RESUMO

Asymmetric copolymerization of meso-epoxide and anhydride is a powerful strategy for preparing various isotactic polyesters with two contiguous stereogenic centers. However, the previous binary systems suffered from slow rates at low loadings, poor enantioselectivities and transesterification reactions at enhanced temperatures. Herein, we report novel dinuclear aluminium complexes with multiple chiralities and ammonium salts anchored on ligand frameworks. These bifunctional catalysts exhibit high activities and enantioselectivities for epoxides/anhydrides copolymerizations at harsh conditions via intramolecularly synergistic catalysis, affording polyesters with unprecedented molecular weights and narrow distributions. Notably, no transesterification reactions were observed, significantly different from the binary catalyst/cocatalyst pairs. This study represents a rare example regarding temperature-independent asymmetric induction for preparing chiral polymers from achiral monomers.

8.
Int J Mol Sci ; 20(23)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775357

RESUMO

Carbon dioxide is commonly used as one of the significant environmental factors to control pileus expansion during mushroom cultivation. However, the pileus expansion mechanism related to CO2 is still unknown. In this study, the young fruiting bodies of a popular commercial mushroom Flammulina filiformis were cultivated under different CO2 concentrations. In comparison to the low CO2 concentration (0.05%), the pileus expansion rates were significantly lower under a high CO2 concentration (5%). Transcriptome data showed that the up-regulated genes enriched in high CO2 concentration treatments mainly associated with metabolism processes indicated that the cell metabolism processes were active under high CO2 conditions. However, the gene ontology (GO) categories and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways associated with cell division processes contained down-regulated genes at both 12 h and 36 h under a high concentration of CO2. Transcriptome and qRT-PCR analyses demonstrated that a high CO2 concentration had an adverse effect on gene expression of the ubiquitin-proteasome system and cell cycle-yeast pathway, which may decrease the cell division ability and exhibit an inhibitory effect on early pileus expansion. Our research reveals the molecular mechanism of inhibition effects on early pileus expansion by elevated CO2, which could provide a theoretical basis for a CO2 management strategy in mushroom cultivation.


Assuntos
Dióxido de Carbono/farmacologia , Divisão Celular , Flammulina/genética , Carpóforos/genética , Proteínas Fúngicas/genética , Transcriptoma/efeitos dos fármacos , Biologia Computacional , Flammulina/efeitos dos fármacos , Flammulina/crescimento & desenvolvimento , Carpóforos/efeitos dos fármacos , Carpóforos/crescimento & desenvolvimento , Perfilação da Expressão Gênica
9.
Zhonghua Nan Ke Xue ; 24(2): 138-141, 2018 Feb.
Artigo em Zh | MEDLINE | ID: mdl-30156073

RESUMO

OBJECTIVE: To explore the strategies of preserving urinary continence in transurethral plasmakinetic enucleation of the prostate (PKEP) for benign prostate hyperplasia (BPH). METHODS: We treated 65 BPH patients by PKEP with preservation of urinary continence (UC-PKEP), which involved protection of the external urethral sphincter in the beginning of surgery, proper preservation of the anterior lobe of the prostate to protect the internal urethral sphincter in the middle, and preservation of the integrity of the bladder neck towards the end. We compared the postoperative status of urinary continence of the patients with that of the 54 BPH cases treated by complete plasmakinetic enucleation of the prostate (Com-PKEP). RESULTS: All the operations were performed successfully with the urinary catheters removed at 5 days after surgery. In comparison with Com-PKEP, UC-PKEP achieved evidently lower incidence rates of urinary incontinence at 24 hours (31.49% vs 13.85%, P <0.05), 1 week (18.52% vs 4.62%, P <0.05), 2 weeks (14.81% vs 3.08%, P <0.05), 1 month (3.70% vs 1.54%, P >0.05), and 3 months (3.70% vs 0%, P >0.05) after catheter removal. Compared with the baseline, the maximum urinary flow rate (Qmax) was significantly improved postoperatively in both the Com-PKEP (ï¼»7.43 ± 3.26ï¼½ vs ï¼»20.58 ± 3.22ï¼½ ml, P <0.05) and the UC-PKEP group (ï¼»8.04 ± 2.28ï¼½ vs ï¼»20.66 ± 3.08ï¼½ ml, P <0.05). CONCLUSIONS: Transurethral PKEP is a safe and effective method for the management of BPH, during which the strategies of avoiding blunt or sharp damage to the external urethral sphincter in the beginning, properly preserving the anterior lobe of the prostate in the middle and preserving the integrity of the bladder neck towards the end may help to achieve rapid recovery of urinary continence.


Assuntos
Tratamentos com Preservação do Órgão/métodos , Hiperplasia Prostática/cirurgia , Ressecção Transuretral da Próstata/métodos , Uretra , Bexiga Urinária , Incontinência Urinária/prevenção & controle , Humanos , Masculino , Período Pós-Operatório , Qualidade de Vida , Ressecção Transuretral da Próstata/efeitos adversos , Resultado do Tratamento , Cateterismo Urinário
10.
Hepatobiliary Pancreat Dis Int ; 14(3): 263-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26063026

RESUMO

BACKGROUND: Portal hypertension is one of the most important clinical conditions that cause intraoperative intensive hemorrhage in cirrhotic patients undergoing liver transplantation. Pre-transplant portal decompression may reduce the intraoperative bleeding during liver transplantation. METHODS: Splenic artery trunk embolization (SATE) was performed one month prior to liver transplantation. Platelet count, prealbumin, international normalized ratio, and blood flow in the portal vein and hepatic artery were monitored before and one month after SATE. The measurements above were collected on admission and before surgery in the non-SATE patients, who served as controls. We also recorded the intraoperative blood loss, operating time, required transfusion, post-transplant ascites, and complications within three months after operation in all patients. RESULTS: SATE significantly reduced portal venous blood flow, increased hepatic arterial blood flow, normalized platelet count, and improved prealbumin and international normalized ratio in the patients before liver transplantation. Compared to the non-SATE patients, the pre-transplant SATE significantly decreased the operating time, intraoperative bleeding, post-transplant ascites and severe surgical complications. CONCLUSION: Pre-transplant SATE decreases portal pressure, improves liver function reserve, and reduces the surgical risk of liver transplantation effectively in patients with severe portal hypertension.


Assuntos
Embolização Terapêutica/métodos , Hipertensão Portal/terapia , Transplante de Fígado/efeitos adversos , Cuidados Pré-Operatórios/métodos , Artéria Esplênica , Adulto , Ascite/etiologia , Ascite/prevenção & controle , Biomarcadores/sangue , Coagulação Sanguínea , Velocidade do Fluxo Sanguíneo , Perda Sanguínea Cirúrgica/prevenção & controle , Embolização Terapêutica/efeitos adversos , Feminino , Artéria Hepática/fisiopatologia , Artéria Hepática/cirurgia , Humanos , Hipertensão Portal/diagnóstico , Hipertensão Portal/fisiopatologia , Coeficiente Internacional Normatizado , Circulação Hepática , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Contagem de Plaquetas , Pressão na Veia Porta , Veia Porta/fisiopatologia , Veia Porta/cirurgia , Pré-Albumina/metabolismo , Cuidados Pré-Operatórios/efeitos adversos , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
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