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1.
Nature ; 608(7922): 413-420, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35922515

RESUMO

High cholesterol is a major risk factor for cardiovascular disease1. Currently, no drug lowers cholesterol through directly promoting cholesterol excretion. Human genetic studies have identified that the loss-of-function Asialoglycoprotein receptor 1 (ASGR1) variants associate with low cholesterol and a reduced risk of cardiovascular disease2. ASGR1 is exclusively expressed in liver and mediates internalization and lysosomal degradation of blood asialoglycoproteins3. The mechanism by which ASGR1 affects cholesterol metabolism is unknown. Here, we find that Asgr1 deficiency decreases lipid levels in serum and liver by stabilizing LXRα. LXRα upregulates ABCA1 and ABCG5/G8, which promotes cholesterol transport to high-density lipoprotein and excretion to bile and faeces4, respectively. ASGR1 deficiency blocks endocytosis and lysosomal degradation of glycoproteins, reduces amino-acid levels in lysosomes, and thereby inhibits mTORC1 and activates AMPK. On one hand, AMPK increases LXRα by decreasing its ubiquitin ligases BRCA1/BARD1. On the other hand, AMPK suppresses SREBP1 that controls lipogenesis. Anti-ASGR1 neutralizing antibody lowers lipid levels by increasing cholesterol excretion, and shows synergistic beneficial effects with atorvastatin or ezetimibe, two widely used hypocholesterolaemic drugs. In summary, this study demonstrates that targeting ASGR1 upregulates LXRα, ABCA1 and ABCG5/G8, inhibits SREBP1 and lipogenesis, and therefore promotes cholesterol excretion and decreases lipid levels.


Assuntos
Receptor de Asialoglicoproteína , Colesterol , Metabolismo dos Lipídeos , Proteínas Quinases Ativadas por AMP/metabolismo , Transportador 1 de Cassete de Ligação de ATP , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Receptor de Asialoglicoproteína/antagonistas & inibidores , Receptor de Asialoglicoproteína/deficiência , Receptor de Asialoglicoproteína/genética , Receptor de Asialoglicoproteína/metabolismo , Assialoglicoproteínas/metabolismo , Atorvastatina/farmacologia , Proteína BRCA1 , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Colesterol/metabolismo , Sinergismo Farmacológico , Endocitose , Ezetimiba/farmacologia , Humanos , Lipídeos/análise , Lipídeos/sangue , Fígado/metabolismo , Receptores X do Fígado/metabolismo , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Proteína de Ligação a Elemento Regulador de Esterol 1 , Ubiquitina-Proteína Ligases/metabolismo
2.
Plant J ; 118(3): 802-822, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38305492

RESUMO

Floral patterns are unique to rice and contribute significantly to its reproductive success. SL1 encodes a C2H2 transcription factor that plays a critical role in flower development in rice, but the molecular mechanism regulated by it remains poorly understood. Here, we describe interactions of the SL1 with floral homeotic genes, SPW1, and DL in specifying floral organ identities and floral meristem fate. First, the sl1 spw1 double mutant exhibited a stamen-to-pistil transition similar to that of sl1, spw1, suggesting that SL1 and SPW1 may located in the same pathway regulating stamen development. Expression analysis revealed that SL1 is located upstream of SPW1 to maintain its high level of expression and that SPW1, in turn, activates the B-class genes OsMADS2 and OsMADS4 to suppress DL expression indirectly. Secondly, sl1 dl displayed a severe loss of floral meristem determinacy and produced amorphous tissues in the third/fourth whorl. Expression analysis revealed that the meristem identity gene OSH1 was ectopically expressed in sl1 dl in the fourth whorl, suggesting that SL1 and DL synergistically terminate the floral meristem fate. Another meristem identity gene, FON1, was significantly decreased in expression in sl1 background mutants, suggesting that SL1 may directly activate its expression to regulate floral meristem fate. Finally, molecular evidence supported the direct genomic binding of SL1 to SPW1 and FON1 and the subsequent activation of their expression. In conclusion, we present a model to illustrate the roles of SL1, SPW1, and DL in floral organ specification and regulation of floral meristem fate in rice.


Assuntos
Flores , Regulação da Expressão Gênica de Plantas , Meristema , Oryza , Proteínas de Plantas , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Plantas Geneticamente Modificadas , Mutação
3.
Plant Cell ; 34(11): 4313-4328, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-35904763

RESUMO

Leaf morphology is one of the most important features of the ideal plant architecture. However, the genetic and molecular mechanisms controlling this feature in crops remain largely unknown. Here, we characterized the rice (Oryza sativa) wide leaf 1 (wl1) mutant, which has wider leaves than the wild-type due to more vascular bundles and greater distance between small vascular bundles. WL1 encodes a Cys-2/His-2-type zinc finger protein that interacts with Tillering and Dwarf 1 (TAD1), a co-activator of the anaphase-promoting complex/cyclosome (APC/C) (a multi-subunit E3 ligase). The APC/CTAD1 complex degrades WL1 via the ubiquitin-26S proteasome degradation pathway. Loss-of-function of TAD1 resulted in plants with narrow leaves due to reduced vascular bundle numbers and distance between the small vascular bundles. Interestingly, we found that WL1 negatively regulated the expression of a narrow leaf gene, NARROW LEAF 1 (NAL1), by recruiting the co-repressor TOPLESS-RELATED PROTEIN and directly binding to the NAL1 regulatory region to inhibit its expression by reducing the chromatin histone acetylation. Furthermore, biochemical and genetic analyses revealed that TAD1, WL1, and NAL1 operated in a common pathway to control the leaf width. Our study establishes an important framework for understanding the APC/CTAD1-WL1-NAL1 pathway-mediated control of leaf width in rice, and provides insights for improving crop plant architecture.


Assuntos
Oryza , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Fenótipo , Mutação/genética , Folhas de Planta/genética , Folhas de Planta/metabolismo
4.
PLoS Biol ; 20(11): e3001851, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36346780

RESUMO

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), responsible for the Coronavirus Disease 2019 (COVID-19) pandemic, causes respiratory failure and damage to multiple organ systems. The emergence of viral variants poses a risk of vaccine failures and prolongation of the pandemic. However, our understanding of the molecular basis of SARS-CoV-2 infection and subsequent COVID-19 pathophysiology is limited. In this study, we have uncovered a critical role for the evolutionarily conserved Hippo signaling pathway in COVID-19 pathogenesis. Given the complexity of COVID-19-associated cell injury and immunopathogenesis processes, we investigated Hippo pathway dynamics in SARS-CoV-2 infection by utilizing COVID-19 lung samples and human cell models based on pluripotent stem cell-derived cardiomyocytes (PSC-CMs) and human primary lung air-liquid interface (ALI) cultures. SARS-CoV-2 infection caused activation of the Hippo signaling pathway in COVID-19 lung and in vitro cultures. Both parental and Delta variant of concern (VOC) strains induced Hippo pathway. The chemical inhibition and gene knockdown of upstream kinases MST1/2 and LATS1 resulted in significantly enhanced SARS-CoV-2 replication, indicating antiviral roles. Verteporfin, a pharmacological inhibitor of the Hippo pathway downstream transactivator, YAP, significantly reduced virus replication. These results delineate a direct antiviral role for Hippo signaling in SARS-CoV-2 infection and the potential for this pathway to be pharmacologically targeted to treat COVID-19.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Via de Sinalização Hippo , Antivirais/farmacologia
5.
Plant J ; 115(1): 37-51, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36970846

RESUMO

Pollen development is critical to plant reproduction, but the underlying regulatory molecular mechanisms have not been fully elucidated. The Arabidopsis (Arabidopsis thaliana) EFR3 OF PLANT 3 (EFOP3) and EFR3 OF PLANT 4 (EFOP4) genes encode members of the Armadillo (ARM) repeat superfamily that play key roles in pollen development. Herein, we demonstrate that EFOP3 and EFOP4 are co-expressed in pollen at anther stages 10-12, but loss-of-function of both EFOP3 and EFOP4 leads to male gametophyte sterility, irregular intine, and shriveled pollen grains at anther stage 12. We further established that full-length EFOP3 and EFOP4 specifically localize to the plasma membrane, and the integrity of these proteins is essential for pollen development. We observed uneven intine, less organized cellulose and reduced pectin content in mutant pollen compared with the wild-type. These, together with the misexpression of several genes related to cell wall metabolism in efop3-/- efop4+/- mutants, suggest that EFOP3 and EFOP4 may indirectly regulate the expression of these genes to affect intine formation, thus controlling Arabidopsis pollen fertility in a functionally redundant manner. Moreover, transcriptome analysis showed that the absence of EFOP3 and EFOP4 function affects multiple pollen development pathways. These results enhance our understanding of EFOPs proteins and their role in pollen development.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Pólen , Fertilidade , Reprodução/genética , Regulação da Expressão Gênica de Plantas
6.
Biochem Biophys Res Commun ; 703: 149637, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38354464

RESUMO

The normal development of pollen grains and the completion of double fertilization in embryos are crucial for both the sexual reproduction of angiosperms and grain production. Actin depolymerizing factor (ADF) regulates growth, development, and responses to biotic and abiotic stress by binding to actin in plants. In this study, the function of the ZmADF1 gene was validated through bioinformatic analysis, subcellular localization, overexpression in maize and Arabidopsis, and knockout via CRISPR/Cas9. The amino acid sequence of ZmADF1 exhibited high conservation and a similar tertiary structure to that of ADF homologs. Subcellular localization analysis revealed that ZmADF1 is localized mainly to the nucleus and cytoplasm. The ZmADF1 gene was specifically expressed in maize pollen, and overexpression of the ZmADF1 gene decreased the number of pollen grains in the anthers of transgenic Arabidopsis plants. The germination rate of pollen and the empty seed shell rate in the fruit pods of the overexpressing plants were significantly greater than those in the wild-type (WT) plants. In maize, the pollen viability of the knockout lines was significantly greater than that of both the WT and the overexpressing lines. Our results confirmed that the ZmADF1 gene was specifically expressed in pollen and negatively regulated pollen quantity, vigor, germination rate, and seed setting rate. This study provides insights into ADF gene function and possible pathways for improving high-yield maize breeding.


Assuntos
Arabidopsis , Destrina , Pólen , Zea mays , Sequência de Aminoácidos , Arabidopsis/metabolismo , Destrina/genética , Destrina/metabolismo , Gelsolina/metabolismo , Regulação da Expressão Gênica de Plantas , Pólen/genética , Pólen/crescimento & desenvolvimento , Zea mays/metabolismo
7.
Small ; 20(15): e2307184, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38012533

RESUMO

Aqueous zinc-ion hybrid capacitors (ZIHCs), as ideal candidates for high energy-power supply systems, are restricted by unsatisfied energy density and poor cycling durability for further applications. The construction of a surface-functionalized carbon cathode is an effective strategy for improving the performance of ZIHCs. Herein, a high-performance ZIHC is achieved using oxygen-rich hierarchically porous carbon rods (MDPC-X) prepared by the pyrolysis of a metal-organic framework (MOF) assisted by KOH activation. The MDPC-X samples displayed high electric double-layer capacitance (EDLC) and pseudocapacitance owing to their oxygen-rich surfaces, abundant electroactive sites, and short ions/electron transfer lengths. The surface oxygen functional groups for the reversible chemical adsorption/desorption of Zn2+ are identified using ex situ X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Consequently, the as-assembled ZIHC exhibited a high capacity of 323.4 F g-1 (161.7 mA h g-1) at 0.5 A g-1 and a retention of 147 F g-1 (73.5 mA h g-1) at an ultrahigh current density of 50 A g-1, corresponding to high energy and power densities of 145.5 W h kg-1 and 45 kW kg-1, respectively. Furthermore, an excellent cycling life with 96.5% of capacity retention is also maintained after 10 000 cycles at 10 A g-1, demonstrating its promising potential for applications.

8.
Hepatology ; 77(3): 774-788, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35908246

RESUMO

BACKGROUND AND AIMS: The sensitivity of current surveillance methods for detecting early-stage hepatocellular carcinoma (HCC) is suboptimal. Extracellular vesicles (EVs) are promising circulating biomarkers for early cancer detection. In this study, we aim to develop an HCC EV-based surface protein assay for early detection of HCC. APPROACH AND RESULTS: Tissue microarray was used to evaluate four potential HCC-associated protein markers. An HCC EV surface protein assay, composed of covalent chemistry-mediated HCC EV purification and real-time immuno-polymerase chain reaction readouts, was developed and optimized for quantifying subpopulations of EVs. An HCC EV ECG score, calculated from the readouts of three HCC EV subpopulations ( E pCAM + CD63 + , C D147 + CD63 + , and G PC3 + CD63 + HCC EVs), was established for detecting early-stage HCC. A phase 2 biomarker study was conducted to evaluate the performance of ECG score in a training cohort ( n  = 106) and an independent validation cohort ( n  = 72).Overall, 99.7% of tissue microarray stained positive for at least one of the four HCC-associated protein markers (EpCAM, CD147, GPC3, and ASGPR1) that were subsequently validated in HCC EVs. In the training cohort, HCC EV ECG score demonstrated an area under the receiver operating curve (AUROC) of 0.95 (95% confidence interval [CI], 0.90-0.99) for distinguishing early-stage HCC from cirrhosis with a sensitivity of 91% and a specificity of 90%. The AUROCs of the HCC EV ECG score remained excellent in the validation cohort (0.93; 95% CI, 0.87-0.99) and in the subgroups by etiology (viral: 0.95; 95% CI, 0.90-1.00; nonviral: 0.94; 95% CI, 0.88-0.99). CONCLUSION: HCC EV ECG score demonstrated great potential for detecting early-stage HCC. It could augment current surveillance methods and improve patients' outcomes.


Assuntos
Carcinoma Hepatocelular , Vesículas Extracelulares , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Biomarcadores Tumorais/análise , Vesículas Extracelulares/química , Proteínas de Membrana , Eletrocardiografia , Glipicanas
9.
Brain Behav Immun ; 120: 256-274, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38852761

RESUMO

Major depressive disorder (MDD) is a global health burden characterized by persistent low mood, deprivation of pleasure, recurrent thoughts of death, and physical and cognitive deficits. The current understanding of the pathophysiology of MDD is lacking, resulting in few rapid and effective antidepressant therapies. Recent studies have pointed to the sigma-1 (σ-1) receptor as a potential rapid antidepressant target; σ-1 agonists have shown promise in a variety of preclinical depression models. Hypidone hydrochloride (YL-0919), an independently developed antidepressant by our institute with faster onset of action and low rate of side effects, has recently emerged as a highly selective σ-1 receptor agonist; however, its underlying astrocyte-specific mechanism is unknown. In this study, we investigated the effect of YL-0919 treatment on gene expression in the prefrontal cortex of depressive-like mice by single-cell RNA sequencing. Furthermore, we knocked down σ-1 receptors on astrocytes in the medial prefrontal cortex of mice to explore the effects of YL-0919 on depressive-like behavior and neuroinflammation in mice. Our results demonstrated that astrocyte-specific knockdown of σ-1 receptor resulted in depressive-like behavior in mice, which was reversed by YL-0919 administration. In addition, astrocytic σ-1 receptor deficiency led to activation of the NF-κB inflammatory pathway, and crosstalk between reactive astrocytes and activated microglia amplified neuroinflammation, exacerbating stress-induced neuronal apoptosis. Furthermore, the depressive-like behavior induced by astrocyte-specific knockdown of the σ-1 receptor was improved by a selective NF-κB inhibitor, JSH-23, in mice. Our study not only reaffirms the σ-1 receptor as a key target of the faster antidepressant effect of YL-0919, but also contributes to the development of astrocytic σ-1 receptor-based novel drugs.

10.
Neurochem Res ; 49(7): 1628-1642, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38416374

RESUMO

Heterotopic ossification (HO) is a pathological process characterized by the aberrant formation of bone in muscles and soft tissues. It is commonly triggered by traumatic brain injury, spinal cord injury, and burns. Despite a wide range of evidence underscoring the significance of neurogenic signals in proper bone remodeling, a clear understanding of HO induced by nerve injury remains rudimentary. Recent studies suggest that injury to the nervous system can activate various signaling pathways, such as TGF-ß, leading to neurogenic HO through the release of neurotrophins. These pathophysiological changes lay a robust groundwork for the prevention and treatment of HO. In this review, we collected evidence to elucidate the mechanisms underlying the pathogenesis of HO related to nerve injury, aiming to enhance our understanding of how neurological repair processes can culminate in HO.


Assuntos
Ossificação Heterotópica , Ossificação Heterotópica/metabolismo , Humanos , Animais , Neurotransmissores/metabolismo , Transdução de Sinais/fisiologia
11.
J Natl Compr Canc Netw ; 22(3)2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38498975

RESUMO

BACKGROUND: Neoadjuvant anti-PD-1 therapy has shown encouraging efficacy in patients with deficient DNA mismatch repair (dMMR)/microsatellite instability-high (MSI-H) locally advanced rectal cancer (LARC), which suggests its potential as a curative-intent therapy and a promising treatment option for organ preservation. We aimed to investigate the long-term outcomes of patients with dMMR/MSI-H LARC who experienced clinical complete response (cCR) after anti-PD-1 therapy. METHODS: We retrospectively analyzed patients with dMMR/MSI-H LARC who achieved cCR and received nonoperative management following neoadjuvant anti-PD-1-based treatment from 4 Chinese medical centers. Patients were followed up for at least 1 year after they achieved cCR, their clinical data were collected, and survival outcomes were analyzed using the Kaplan-Meier method. RESULTS: A total of 24 patients who achieved cCR and received nonoperative management from March 2018 to May 2022 were included, with a median age of 51.0 years (range, 19.0-77.0 years). The median treatment course to reach cCR was 6.0 (range, 1.0-12.0). Fifteen patients (62.5%) continued their treatments after experiencing cCR, and the median treatment course was 17.0 (range, 3.0-36.0). No local regrowth or distant metastasis was observed in a median follow-up time of 29.1 months (range, 12.6-48.5 months) after cCR. The 3-year disease-free and overall survivals were both 100%. CONCLUSIONS: Patients with dMMR/MSI-H locally advanced or low-lying rectal cancer who achieved cCR following anti-PD-1-based therapy had promising long-term outcomes. A prospective clinical trial with a larger sample size is required to further validate these findings.


Assuntos
Neoplasias Colorretais , Neoplasias Retais , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Neoplasias Colorretais/genética , Reparo de Erro de Pareamento de DNA , Imunoterapia , Instabilidade de Microssatélites , Terapia Neoadjuvante , Neoplasias Retais/genética , Neoplasias Retais/terapia , Estudos Retrospectivos , Resultado do Tratamento
12.
Arterioscler Thromb Vasc Biol ; 43(7): 1219-1233, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37165876

RESUMO

BACKGROUND: Lower plasma levels of LDL (low-density lipoprotein) cholesterol (LDL-C) can reduce the risk of atherosclerotic cardiovascular disease. The loss-of-function mutations in PCSK9 (proprotein convertase subtilisin/kexin type 9) have been known to associate with low LDL-C in many human populations. PCSK9 genetic variants in Chinese Uyghurs who are at high risk of atherosclerotic cardiovascular disease due to their dietary habits have not been reported. METHODS: The study involved the whole-exome and target sequencing of college students from Uyghur and other ethnic groups in Xinjiang, China, for the association of PCSK9 loss-of-function mutations with low plasma levels of LDL-C. The mechanisms by which the identified mutations affect the function of PCSK9 were investigated in cultured cells using biochemical and cell assays. The causal effects of the identified PCSK9 mutations on LDL-C levels were verified in mice injected with adeno-associated virus expressing different forms of PCSK9 and fed a high-cholesterol diet. RESULTS: We identified 2 PCSK9 mutations-E144K and C378W-in Chinese Uyghurs with low plasma levels of LDL-C. The E144K and C378W mutations impaired the maturation and secretion of the PCSK9 protein, respectively. Adeno-associated virus-mediated expression of E144K and C378W mutants in Pcsk9 KO (knockout) mice fed a high-cholesterol diet also hampered PCSK9 secretion into the serum, resulting in elevated levels of LDL receptor in the liver and reduced levels of LDL-C in the serum. CONCLUSIONS: Our study shows that E144K and C378W are PCSK9 loss-of-function mutations causing low LDL-C levels in mice and probably in humans as well.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Hipercolesterolemia , Humanos , Camundongos , Animais , Pró-Proteína Convertase 9/genética , LDL-Colesterol , Serina Endopeptidases/genética , Pró-Proteína Convertases/genética , Pró-Proteína Convertases/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , Camundongos Knockout , Aterosclerose/genética , Aterosclerose/prevenção & controle , Aterosclerose/metabolismo , Mutação
13.
J Pharmacol Sci ; 154(4): 236-245, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38485341

RESUMO

Postpartum depression (PPD) is a significant contributor to maternal morbidity and mortality. The Sigma-1 (σ-1) receptor has received increasing attention in recent years because of its ability to link different signaling systems and exert its function in the brain through chaperone actions, especially in neuropsychiatric disorders. YL-0919, a novel σ-1 receptor agonist developed by our institute, has shown antidepressive and anxiolytic effects in a variety of animal models, but effects on PPD have not been revealed. In the present study, excitatory/inhibitory signaling in the hippocampus was reflected by GABA and glutamate and their associated excitatory-inhibitory receptor proteins, the HPA axis hormones in the hippocampus were assessed by ELISA. Finally, immunofluorescence for markers of newborn neuron were undertaken in the dentate gyri, along with dendritic spine staining and dendritic arborization tracing. YL-0919 rapidly improves anxiety and depressive-like behavior in PPD-like mice within one week, along with normalizing the excitation/inhibition signaling as well as the HPA axis activity. YL-0919 rescued the decrease in hippocampal dendritic complexity and spine density induced by estrogen withdrawal. The study results suggest that YL-0919 elicits a therapeutic effect on PPD-like mice; therefore, the σ-1 receptor may be a novel promising target for PPD treatment in the future.


Assuntos
Ácido Glutâmico , Receptor Sigma-1 , Feminino , Camundongos , Animais , Ácido Glutâmico/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Hipocampo/metabolismo , Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Estrogênios , Plasticidade Neuronal , Ácido gama-Aminobutírico/metabolismo
14.
Acta Pharmacol Sin ; 45(4): 704-713, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38097715

RESUMO

Sigma-1 receptor (S1R) is a unique multi-tasking chaperone protein in the endoplasmic reticulum. Since S1R agonists exhibit potent antidepressant-like activity, S1R has become a novel target for antidepression therapy. With a rapid and sustained antidepressant effect, ketamine may also interact with S1R. In this study, we investigated whether the antidepressant action of ketamine was related to S1R activation. Depression state was evaluated in the tail suspension test (TST) and a chronic corticosterone (CORT) procedure was used to induce despair-like behavior in mice. The neuronal activities and structural changes of pyramidal neurons in medial prefrontal cortex (mPFC) were assessed using fiber-optic recording and immunofluorescence staining, respectively. We showed that pharmacological manipulation of S1R modulated ketamine-induced behavioral effect. Furthermore, pretreatment with an S1R antagonist BD1047 (3 mg·kg-1·d-1, i.p., for 3 consecutive days) significantly weakened the structural and functional restoration of pyramidal neuron in mPFC caused by ketamine (10 mg·kg-1, i.p., once). Ketamine indirectly triggered the activation of S1R and subsequently increased the level of BDNF. Pretreatment with an S1R agonist SA4503 (1 mg·kg-1·d-1, i.p., for 3 consecutive days) enhanced the sustained antidepressant effect of ketamine, which was eliminated by knockdown of BDNF in mPFC. These results reveal a critical role of S1R in the sustained antidepressant effect of ketamine, and suggest that a combination of ketamine and S1R agonists may be more beneficial for depression patients.


Assuntos
Antidepressivos , Fator Neurotrófico Derivado do Encéfalo , Ketamina , Receptor Sigma-1 , Animais , Humanos , Camundongos , Antidepressivos/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Depressão/tratamento farmacológico , Ketamina/farmacologia , Neurônios , Córtex Pré-Frontal/metabolismo , Receptor Sigma-1/agonistas
15.
Appl Opt ; 63(16): 4386-4395, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856618

RESUMO

Reflective mirrors are the key imaging components of space-borne telescopes, which require a high lightweight ratio integrated with excellent optical properties. In this context, a novel, to our knowledge, 2.5D centroidal Voronoi tessellation (CVT) generation methodology is proposed for designing and optimizing a lightweight mirror structure. Firstly, the initial designs are obtained combining global sensitivity factor mapping and local distribution optimization. Then, the optimal model is selected through multi-objective optimization and decision making. Subsequently, the FEA (finite element analysis) results indicate that, under the same mass, the proposed design exhibits better optomechanical performance. Finally, in practical applications, the approach presented in this paper outperforms the traditional design for each technological requirement, including a 62% reduction in RMS and a higher lightweight ratio. This method offers a kind of novel design and optimization process for space-based optomechanical lightweight structures.

16.
Endocr J ; 71(5): 537-542, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38508775

RESUMO

Bartter syndrome (BS) is a rare, inherited salt-losing renal tubular disorder characterized by secondary hyperaldosteronism, hypokalemia, hypochloremia, metabolic alkalosis, and low-to-normal blood pressure. Classic BS, or BS Type 3, the most common subtype in the Asian population, is caused by a molecular defect in ClC-Kb, a voltage-gated chloride channel in renal tubules, due to CLCNKB gene mutation. Because the onset of BS is more common in children than in adults, the diagnosis, treatment outcomes, genotype/phenotype association, and follow-up of adult-onset BS Type 3 are limited. This case report describes the findings in a 20-year-old man who was admitted with hypokalemic paralysis, with clinical manifestations were similar to those of Gitelman syndrome (GS); however, the patient was later diagnosed to have BS Type 3 through genetic testing (NM_000085.4 (CLCNKB): c.1052G>T). A literature review showed that no homozygous mutations have been reported to date. After 5 years of treatment and follow-up, we found that this genotype requires high levels of potassium and is prone to urinary protein and metabolic syndrome. Distinguishing adult-onset BS from GS is challenging in clinical practice. However, genetic diagnosis can help solve this problem effectively, and genotypes play a guiding role in treatment planning.


Assuntos
Síndrome de Bartter , Canais de Cloreto , Humanos , Masculino , Adulto Jovem , Síndrome de Bartter/genética , Síndrome de Bartter/diagnóstico , Síndrome de Bartter/complicações , Canais de Cloreto/genética , Seguimentos , Síndrome de Gitelman/genética , Síndrome de Gitelman/diagnóstico , Síndrome de Gitelman/complicações , Mutação
17.
Biochem Genet ; 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38244156

RESUMO

Colorectal carcinoma (CRC) is one of the most common malignant tumors in the digestive tract. It was found that butyric acid could inhibit the expression of miR-183 to slow down malignant progression of CRC in the early stage. However, its regulatory mechanism remains unclear. This study screened the IC50 value of butyrate on inhibition of CRC cells malignant progression. Its inhibitory effects were detected by MTT assay, colony formation experiment, Transwell migration experiment, and apoptosis evaluation by flow cytometry. Next, the expressions of miR-183 and DNAJB4 were, respectively, determined in butyrate treated and miR-183 analog or si-DNAJB4-transfected CRC cells to further detect the role of upregulated miR-183 or silencing DNAJB4 in CRC cells malignant progression. Subsequently, the targeted regulatory relationship between miR-183 and si-DNAJB4 was confirmed by bioinformatic prediction tools and double luciferase report genes analysis method. The regulatory mechanism of butyrate on miR-183/DNAJB4 axis signal pathway was evaluated in molecular level, and verified in nude mouse xerograft tumor model and immunohistochemical analysis tests of Ki67 positive rates. The results displayed that butyrate with increased concentration can hinder the proliferation and improve apoptosis of CRC cells by decreasing the expression of miR-183. Thus, butyrate reduces miR-183 expression and increases DNAJB4 expression via the miR-183/DNAJB4 axis, ultimately inhibiting the malignant progression and increasing apoptosis of CRC. While over expression of miR-183 downregulate the expression of DNAJB4, which can reverse the inhibitory effect of butyrate.

18.
Ann Surg ; 277(4): 557-564, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36538627

RESUMO

OBJECTIVE: To compare neoadjuvant chemotherapy (nCT) with CAPOX alone versus neoadjuvant chemoradiotherapy (nCRT) with capecitabine in locally advanced rectal cancer (LARC) with uninvolved mesorectal fascia (MRF). BACKGROUND DATA: nCRT is associated with higher surgical complications, worse long-term functional outcomes, and questionable survival benefits. Comparatively, nCT alone seems a promising alternative treatment in lower-risk LARC patients with uninvolved MRF. METHODS: Patients between June 2014 and October 2020 with LARC within 12 cm from the anal verge and uninvolved MRF were randomly assigned to nCT group with 4 cycles of CAPOX (Oxaliplatin 130 mg/m2 IV day 1 and Capecitabine 1000 mg/m2 twice daily for 14 d. Repeat every 3 wk) or nCRT group with Capecitabine 825 mg/m² twice daily administered orally and concurrently with radiation therapy (50 Gy/25 fractions) for 5 days per week. The primary end point is local-regional recurrence-free survival. Here we reported the results of secondary end points: histopathologic response, surgical events, and toxicity. RESULTS: Of the 663 initially enrolled patients, 589 received the allocated treatment (nCT, n=300; nCRT, n=289). Pathologic complete response rate was 11.0% (95% CI, 7.8-15.3%) in the nCT arm and 13.8% (95% CI, 10.1-18.5%) in the nCRT arm ( P =0.33). The downstaging (ypStage 0 to 1) rate was 40.8% (95% CI, 35.1-46.7%) in the nCT arm and 45.6% (95% CI, 39.7-51.7%) in the nCRT arm ( P =0.27). nCT was associated with lower perioperative distant metastases rate (0.7% vs. 3.1%, P =0.03) and preventive ileostomy rate (52.2% vs. 63.6%, P =0.008) compared with nCRT. Four patients in the nCT arm received salvage nCRT because of local disease progression after nCT. Two patients in the nCT arm and 5 in the nCRT arm achieved complete clinical response and were treated with a nonsurgical approach. Similar results were observed in subgroup analysis. CONCLUSIONS: nCT achieved similar pCR and downstaging rates with lower incidence of perioperative distant metastasis and preventive ileostomy compared with nCRT. CAPOX could be an effective alternative to neoadjuvant therapy in LARC with uninvolved MRF. Long-term follow-up is needed to confirm these results.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Humanos , Terapia Neoadjuvante/métodos , Resultado do Tratamento , Capecitabina/uso terapêutico , Neoplasias Retais/patologia , Quimiorradioterapia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estadiamento de Neoplasias
19.
J Comput Chem ; 44(4): 581-593, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36326119

RESUMO

Si69 and Si75, typical commodities of silane coupling agents, are often employed in tire recipes to work as the bridges connecting silica and polymers, with which rolling resistance and wet traction are enhanced without loss in abrasion resistance. In this article, the reactivities of Si69 and Si75 with silica and various rubbers were theoretically investigated by using density functional theory (DFT). When the agents were coupled with silica, not only the acid+water condition but also the pure acid condition was confirmed to readily trigger the condensation reactions. The corresponding Gibbs free energy barriers were related to the charge distributions of reaction regions. As the agents suffered from the homolysis of central SS bonds, the generated single-S-tailer radicals (RS·) showed significantly higher reactivities of both the radical addition and the α-H transfer reactions with rubbers, due to the stronger radical philicities of the terminal sulfur radicals with larger condensed local softnesses [s0 (S)]. When the agents underwent the heterolysis of central SS bonds, the terminal sulfur anions with smaller s- (S) indices, however, facilitated the nucleophilic addition reactions with rubbers. Several derivative indices based on the condensed local softnesses were also proposed here to shed light on the reactivities from the viewpoint of the relationship between energy barriers and electronic characteristics. The above findings pave the way for the design of new kinds of silane coupling agents using computer-aided techniques, and meanwhile, provide references for the practical application of Si69 and Si75 to the silica/rubbers systems.

20.
BMC Med ; 21(1): 161, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37106440

RESUMO

BACKGROUND: The objective response rate of microsatellite instability-high (MSI-H) metastatic colorectal cancer (mCRC) patients with first-line anti-programmed cell death protein-1 (PD-1) monotherapy is only 40-45%. Single-cell RNA sequencing (scRNA-seq) enables unbiased analysis of the full variety of cells comprising the tumor microenvironment. Thus, we used scRNA-seq to assess differences among microenvironment components between therapy-resistant and therapy-sensitive groups in MSI-H/mismatch repair-deficient (dMMR) mCRC. Resistance-related cell types and genes identified by this analysis were subsequently verified in clinical samples and mouse models to further reveal the molecular mechanism of anti-PD-1 resistance in MSI-H or dMMR mCRC. METHODS: The response of primary and metastatic lesions to first-line anti-PD-1 monotherapy was evaluated by radiology. Cells from primary lesions of patients with MSI-H/dMMR mCRC were analyzed using scRNA-seq. To identify the marker genes in each cluster, distinct cell clusters were identified and subjected to subcluster analysis. Then, a protein‒protein interaction network was constructed to identify key genes. Immunohistochemistry and immunofluorescence were applied to verify key genes and cell marker molecules in clinical samples. Immunohistochemistry, quantitative real-time PCR, and western blotting were performed to examine the expression of IL-1ß and MMP9. Moreover, quantitative analysis and sorting of myeloid-derived suppressor cells (MDSCs) and CD8+ T cells were performed using flow cytometry. RESULTS: Tumor responses in 23 patients with MSI-H/dMMR mCRC were evaluated by radiology. The objective response rate was 43.48%, and the disease control rate was 69.57%. ScRNA-seq analysis showed that, compared with the treatment-resistant group, the treatment-sensitive group accumulated more CD8+ T cells. Experiments with both clinical samples and mice indicated that infiltration of IL-1ß-driven MDSCs and inactivation of CD8+ T cells contribute to anti-PD-1 resistance in MSI-H/dMMR CRC. CONCLUSIONS: CD8+ T cells and IL-1ß were identified as the cell type and gene, respectively, with the highest correlation with anti-PD-1 resistance. Infiltration of IL-1ß-driven MDSCs was a significant factor in anti-PD-1 resistance in CRC. IL-1ß antagonists are expected to be developed as a new treatment for anti-PD-1 inhibitor resistance.


Assuntos
Neoplasias Colorretais , Instabilidade de Microssatélites , Animais , Camundongos , Linfócitos T CD8-Positivos/patologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Imuno-Histoquímica , Microambiente Tumoral
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