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1.
J Mol Recognit ; : e3085, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38599335

RESUMO

Many proteins could aggregate into amyloid fibrils under certain conditions. However, the aggregation process and morphology of the fibrils may be significantly different because of the distinct protein structure. In this article, the hydrophilic carbon dots (Lys-CA-CDs) were prepared using lysine (Lys) and citric acid (CA) as reactant under the assistance of a microwave. The dissimilar modulation effect of Lys-CA-CDs on the aggregation process of distinct structure protein was further investigated, where bovine serum albumin (BSA) and hen egg white lysozyme (HEWL) were chosen as model proteins. All results showed that Lys-CA-CDs displayed the contrary influence on the aggregation process of BSA and HEWL. Lys-CA-CDs could induce BSA to aggregate into more wormlike fibrils and inhibit the aggregation of HEWL into hair-like fibrils. The influence on the aggregation process of BSA may be assigned to the increased concentration of BSA around the Lys-CA-CDs caused by their interaction. However, inserting of Lys-CA-CDs into the inner structure of HEWL led to the change of protein secondary structure. The change of secondary structure further made it difficult for HEWL to aggregate into fibrils and Lys-CA-CDs showed the inhibition effect on HEWL aggregation.

2.
J Ethnopharmacol ; 326: 117988, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38428657

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Perioperative or postoperative adjuvant chemotherapy based on 5-fluorouracil (5-FU) is a common first-line adjuvant therapy for gastric cancer (GC). However, drug resistance and the side effects of 5-FU have reduced its efficacy. Among these side effects, gastrointestinal (GI) toxicity is one of the most common. Xianglian Pill (XLP) is a Chinese patent medicine that is commonly used for the treatment of diarrhoea. It can reduce inflammation and has a protective effect on the intestinal mucosa. Recent studies have shown that many components of XLP can inhibite tumor cell growth. However, the therapeutic effect of XLP in combination with 5-FU on GC is unclear. AIM OF THE STUDY: To investigate whether the combination of XLP and 5-FU can enhance anti-GC activity while reducing GI toxicity. MATERIALS AND METHODS: XLP was administered orally during intraperitoneal injection of 5-FU in GC mice model. Mice were continuously monitored for diarrhea and xenograft tumor growth. After 2 weeks, the mice were sacrificed and serum was collected to determine interleukin-6 levels. Pathological changes, the expression of pro-inflammatory factors and p38 mitogen-activated protein kinase (MAPK) in GI tissue were determined by Western blot analysis. Pathological changes, apoptosis levels and p38 MAPK expression levels in xenograft tissues were also determined. RESULTS: The results showed that XLP could alleviate GI mucosal injury caused by 5-FU, alleviated diarrhea, and inhibited the expression of nuclear factor (NF)-κB and myeloid differentiation primary response-88. Besides, XLP could promote the 5-FU-induced apoptosis of GC cells and enhance the inhibitory effect of 5-FU on tumor xenografts. Further study showed that XLP administration could regulate the expression of p38 MAPK. CONCLUSIONS: XLP in combination with 5-FU could alleviate its GI side effects and enhance its inhibitory effect on xenograft tumor. Moreover, these effects were found to be related to the regulation of the p38 MAPK/NF-κB pathway.


Assuntos
Medicamentos de Ervas Chinesas , Fluoruracila , Neoplasias Gástricas , Humanos , Camundongos , Animais , Fluoruracila/toxicidade , Neoplasias Gástricas/tratamento farmacológico , NF-kappa B/metabolismo , Sistema de Sinalização das MAP Quinases , Diarreia/induzido quimicamente , Diarreia/tratamento farmacológico , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
3.
Fitoterapia ; 175: 105916, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38527590

RESUMO

Six previously unreported solanidane steroidal alkaloids, namely lyrasolanosides A-F, were isolated from Solanum lyratum. In addition, five known steroidal alkaloids were also identified. The structures of these compounds were determined through the use of NMR, HRESIMS,UV, IR and ECD analysis. To assess their bioactivities, the cytotoxic effects of the six previously unreported compounds were evaluated on A549 cells. The results revealed that lyrasolanoside B (2) exhibited the highest potency among them. Lyrasolanoside B (2) exhibited significant inhibition of cell migration, invasion, and adhesion dramatically. Mechanistically, it was found to suppress the activity of JAK2/STAT3 signaling pathway by downregulating the expression of phosphorylated JAK2/STAT3 in an exosome-dependent manner. In addition, lyrasolanoside B (2) was found to significantly upregulate the expression of E-cadherin and downregulate the expression of N-cadherin and vimentin. These findings indicate that lyrasolanoside B (2) inhibits the metastasis of A549 cells by suppressing exosome-mediated EMT. These findings suggest that lyrasolanoside B (2) may inhibit the metastasis of lung cancer by regulating A549-derived exosomes.

4.
Stem Cell Res ; 76: 103369, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38430735

RESUMO

Neurodevelopmental disorder with or without autistic features and/or structural brain abnormalities (NEDASB) is a rare autosomal dominant disorder caused by a heterozygous mutation in the NOVA2 gene on chromosome 19q13. Here, we describe the generation and characterization of an iPSC line derived from the peripheral blood of a 7-year-old patient carrying a novel heterozygous mutation in NOVA2 (c.625 del). The iPSCs with the confirmed patient-specific mutation were demonstrated by pluripotency markers, a normal karyotype, and the ability to differentiate into three germ layers. This NOVA2-mutant iPSC line could facilitate disease modeling and therapy development studies for NEDASB.


Assuntos
Células-Tronco Pluripotentes Induzidas , Humanos , Criança , Células-Tronco Pluripotentes Induzidas/metabolismo , Diferenciação Celular/genética , Cariótipo , Mutação , Camadas Germinativas , Leucócitos Mononucleares/metabolismo , Antígeno Neuro-Oncológico Ventral
5.
Phytochemistry ; 220: 113999, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38281703

RESUMO

Five undescribed eudesmane methyl esters (1-5), three undescribed eudesmane-12,6-olides (6-8), and 21 known analogues (9-29) were isolated from the aerial part of Artemisia princeps Pamp. Their structures were established by detailed analysis of the NMR and HRESIMS data. The absolute configurations of 1-8 were determined based on single-crystal X-ray diffraction analysis and ECD calculations. Moreover, the inhibitory effects on LPS-induced NO production in BV-2 microglial cells of all the isolated compounds were assessed. Except for compounds 2, 4, 10, and 11, the others showed significant inhibitory activities, with IC50 values of 0.73-18.66 µM, wherein the potential structure-activity relationship was also discussed.


Assuntos
Artemisia , Sesquiterpenos de Eudesmano , Sesquiterpenos , Artemisia/química , Estrutura Molecular , Sesquiterpenos/química , Relação Estrutura-Atividade , Sesquiterpenos de Eudesmano/farmacologia , Sesquiterpenos de Eudesmano/química
6.
Org Lett ; 26(4): 781-785, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38241637

RESUMO

A pair of novel chiral 1-phenylethylamine-modified twistarenes (4 and 11; compound 4 = 9,14-di-tert-butyl-7,16-diphenyl-2-(1-phenylethyl)-1H-benzo[8',9']triphenyleno[2',3':6,7]fluoreno[2,1,9-def]isoquinoline-1,3(2H)-dione) have been synthesized and characterized, and how the solvent component affects the chirality transfer of their self-assembled processes is investigated in mixtures with THF and H2O. The ordered assembly of 11 exhibits circular dichroism response. In addition, both 11a and 11b display positive photoconducting behavior.

7.
Sci Rep ; 14(1): 1502, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233602

RESUMO

HBV-miR-3 is encoded by HBV and takes part in pathogenesis of HBV-related liver disease. Whether HBV-miR-3 has a relationship with HBV replication and is predictive of PegIFN-α treatment response is still unknown. HBV-miR-3 quantification is based on qRT-PCR. The relationship of HBV-miR-3 and HBV replication, and predictive value of HBV-miR-3 were evaluated in a cohort of 650 HBeAg positive patients from a multi-center, randomized phase III clinical trial for the study of PegIFN-a2b. HBV-miR-3 is significantly positively related to HBVDNA, HBVpgRNA, HBeAg and HBsAg at baseline and at all the different time points during PegIFN-α treatment. Both univariate regression analyses and multivariate logistic regression analyses showed HBV-miR-3 is a predictor of HBeAg seroconversion in the patients treated with PegIFN-α at weeks of 0, 12, and 24. 70.0% of patients with HBV-miR-3 < 3log at week 12 achieved HBeAg seroconversion, otherwise, with HBV-miR-3 > 6log at week 12 no patient obtained HBeAg seroconversion. Conbination of HBV-miR-3 and HBeAg is more strongly predictive of HBeAg seroconversion (83.64%) at week 12. HBV-miR-3 is new biomarker for HBV replication and positively correlated to HBV replication. HBV-miR-3 is also an early predictor of HBeAg seroconversion in the patients treated with PegIFN-α.


Assuntos
Antivirais , MicroRNAs , Humanos , Antivirais/uso terapêutico , Vírus da Hepatite B/genética , Interferon-alfa/uso terapêutico , Antígenos E da Hepatite B , Soroconversão , Polietilenoglicóis/uso terapêutico , Resultado do Tratamento , DNA Viral , Proteínas Recombinantes/uso terapêutico
8.
Front Pharmacol ; 14: 1253013, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074148

RESUMO

Background: Penthorum chinense Pursh (PCP) is widely utilized in China to treat a variety of liver diseases. It has been shown that flavonoids inhibit inflammation and have the potential to attenuate tissue damage and fibrosis. However, the mechanisms underlying how total flavonoids isolated from PCP (TFPCP) exert their anti-fibrotic effects remain unclear. Methods: The chemical composition of TFPCP was determined using UHPLC-Q-Orbitrap HRMS. Subsequently, rats were randomly assigned to a control group (Control), a carbon tetrachloride (CCl4)-induced hepatic fibrosis model group (Model), a positive control group [0.2 mg/(kg∙day)] of Colchicine), and three TFPCP treatment groups [50, 100, and 150 mg/(kg∙day)]. All substances were administered by gavage and treatments lasted for 9 weeks. Simultaneously, rats were intraperitoneally injected with 10%-20% CCl4 for 9 weeks to induce liver fibrosis. At the end of the experiment, the liver ultrasound, liver histomorphological, biochemical indicators, and inflammatory cytokine levels were tested respectively. The underlying mechanisms were assessed using Western blot, immunohistochemistry, immunofluorescence, RT-qPCR, and metabolomics. Results: Fourteen flavonoids were identified in TFPCP. Compared with control animals, CCl4-treated rats demonstrated obvious liver injury and fibrosis, manifested as increases in gray values, distal diameter of portal vein (DDPV) and a decrease in blood flow velocity (VPV) in the ultrasound analysis; increased biochemical index values (serum levels of ALT, AST, TBIL, and ALP); marked increases in the contents of fibrotic markers (PC III, COL4, LN, HA) and inflammatory factors (serum TNF-α, IL-6, and IL-1ß); and significant pathological changes. However, compared with the Model group, the ultrasound parameters were significantly improved and the serum levels of inflammatory cytokines were reduced in the TFPCP group. In contrast, the expression of TGF-ß1, TLR4, and MyD88, as well as the p-P65/P65 and p-IκBα/IκBα ratios, were considerably reduced following TFPCP treatment. In addition, we identified 32 metabolites exhibiting differential abundance in the Model group. Interestingly, TFPCP treatment resulted in the restoration of the levels of 20 of these metabolites. Conclusion: Our findings indicated that TFPCP can ameliorate hepatic fibrosis by improving liver function and morphology via the inactivation of the TLR4/MyD88-mediated NF-κB pathway and the regulation of liver metabolism.

9.
J Perinatol ; 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066226

RESUMO

PURPOSE: To investigate in-hospital mortality and hospital length of stay (LOS) in infants requiring tracheostomy with bronchopulmonary dysplasia (BPD). METHODS: We explored the correlation between tracheostomy with in-hospital mortality and LOS in infant patients hospitalized with BPD, using the data from Nationwide Inpatient Sample between 2008 and 2017 in the United States. In-hospital mortality and LOS was compared in patients who underwent tracheostomy with those patients who did not after propensity-score matching. RESULTS: A total of 10,262 children ≤2 years old hospitalized with BPD, 847 (8%) underwent tracheostomy, and 821 patients underwent tracheostomy were matched with 1602 patients without tracheostomy. Tracheostomy group was correlated with higher in-hospital mortality(OR(95%CI):2.98(2.25-3.95)) and prolonged LOS(absolute difference(95%CI):97.0(85.6-108.4)). CONCLUSIONS: Tracheostomy was correlated with increased in-hospital mortality and prolonged LOS. Such information may contribute to better decision-making process between clinicians and parents regarding tracheostomy to manage parent expectations, as well as better interdisciplinary teamwork.

10.
BMC Med ; 21(1): 416, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37919742

RESUMO

BACKGROUND: Progressive reduction of sodium intake is an attractive approach for addressing excessive salt intake, but evidence for this strategy in real practice is limited. We aimed to determine the feasibility, effectiveness, and safety of a progressive sodium intake reduction intervention in real-world setting. METHODS: We randomized 48 residential elderly care facilities in China, with 1612 participants aged 55 years and older, to either progressive reduction (PR, 24 facilities) or no reduction (NR, 24 facilities) of the supply of study salt to the kitchens of these facilities for 2 years. The primary efficacy outcome was systolic blood pressure (SBP) at any scheduled follow-up visit. Secondary efficacy outcomes included diastolic blood pressure (DBP) at any scheduled follow-up visit, and major adverse cardiovascular events (comprising non-fatal stroke, non-fatal myocardial infarction, hospitalized non-fatal heart failure, or vascular death) and total mortality. The perception of food saltiness, the addition of out-of-study salt in meals, and 24-h urinary sodium excretion were used as process indicators. RESULTS: Pre-specified analysis per randomization found no effect of the intervention on the 2-year overall mean systolic and diastolic blood pressure (SBP, DBP) and any other outcomes. However, post hoc analysis showed that the intervention effect on blood pressure varied over multiple follow-up visits (p for interaction < 0.046) and presented favorable differences at the 24-month visit (SBP = - 3.0 mmHg, 95%CI = - 5.6, - 0.5; p = 0.020; DBP = - 2.0 mmHg, 95%CI - 3.4, - 0.63; p = 0.004). The effect on 24-h sodium was non-significant (- 8.4 mmol, 95%CI = - 21.8 to 4.9, p = 0.216), though fewer participants with NR than with PR reported food tasting bland (odds ratio 0.46; 95%CI 0.29 to 0.73; p = 0.001). Reporting of bland food taste and other process measures indicated that intervention delivery and adherence were not fully achieved as designed. CONCLUSIONS: The experience of this real-world study demonstrated that achieving acceptability and sustainability of the progressive sodium intake reduction strategy among older adults was challenging, but it has shown potential for effectiveness in these and potentially other residential settings if the lessons of DECIDE-Salt are applied in further studies. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03290716).


Assuntos
Hipertensão , Cloreto de Sódio na Dieta , Idoso , Humanos , Pessoa de Meia-Idade , Pressão Sanguínea/fisiologia , Cloreto de Sódio na Dieta/efeitos adversos
11.
J Phys Chem Lett ; 14(47): 10509-10516, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37970815

RESUMO

Polarization-sensitive detectors have significant applications in modern communication and information processing. In this study. We present a polarization-sensitive detector based on a MoTe2/WTe2 heterojunction, where WTe2 forms a favorable bandgap structure with MoTe2 after forming the heterojunction. This enhances the carrier separation efficiency and photoelectric response. We successfully achieved wide spectral detection ranging from visible to near-infrared light. Specifically, under zero bias, our photodetector exhibits a responsivity (R) of 0.6 A/W and a detectivity (D*) of 3.6 × 1013 Jones for 635 nm laser illumination. Moreover, the photoswitching ratio can approach approximately 6.3 × 105. Importantly, the polarization sensitivity can reach 3.5 (5.2) at 635 (1310) nm polarized light at zero bias. This study both unveils potential for utilizing MoTe2/WTe2 heterojunctions as polarization-sensitive detectors and provides novel insights for developing high-performance optoelectronic devices.

12.
Front Mol Neurosci ; 16: 1237745, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37664242

RESUMO

Background: Cerebral palsy (CP) is a neurodevelopmental disorder characterized by motor impairment. In this study, we aimed to describe the characteristics of amino acids (AA) in the plasma of children with CP and identify AA that could play a potential role in the auxiliary diagnosis and treatment of CP. Methods: Using high performance liquid chromatography, we performed metabolomics analysis of AA in plasma from 62 CP children and 60 healthy controls. Univariate and multivariate analyses were then applied to characterize different AA. AA markers associated with CP were then identified by machine learning based on the Lasso regression model for the validation of intra-sample interactions. Next, we calculated a discriminant formula and generated a receiver operating characteristic (ROC) curve based on the marker combination in the discriminant diagnostic model. Results: A total of 33 AA were detected in the plasma of CP children and controls. Compared with controls, 5, 7, and 10 different AA were identified in total participants, premature infants, and full-term infants, respectively. Of these, ß-amino-isobutyric acid [p = 2.9*10(-4), Fold change (FC) = 0.76, Variable importance of protection (VIP) = 1.75], tryptophan [p = 5.4*10(-4), FC = 0.87, VIP = 2.22], and asparagine [p = 3.6*10(-3), FC = 0.82, VIP = 1.64], were significantly lower in the three groups of CP patients than that in controls. The combination of ß-amino-isobutyric acid, tryptophan, and taurine, provided high levels of diagnostic classification and risk prediction efficacy for preterm children with an area under the curve (AUC) value of 0.8741 [95% confidence interval (CI): 0.7322-1.000]. The discriminant diagnostic formula for preterm infant with CP based on the potential marker combination was defined by p = 1/(1 + e-(8.295-0.3848* BAIBA-0.1120*Trp + 0.0108*Tau)). Conclusion: Full-spectrum analysis of amino acid metabolomics revealed a distinct profile in CP, including reductions in the levels of ß-amino-isobutyric acid, tryptophan, and taurine. Our findings shed new light on the pathogenesis and diagnosis of premature infants with CP.

13.
Nanoscale ; 15(24): 10223-10231, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37272869

RESUMO

Based on the charge-polarity control, a novel anti-ambipolar heterotransistor is proposed based on a special In2Se3&WSe2 van der Waals heterostructure. Unlike traditional logic transistors, our anti-ambipolar heterotransistor can treat an optical signal as an input to change its operating state, that is, with the switching of the optical signal, it shows a reversible polarity change between anti-ambipolar and P-type. Moreover, with the increase of laser power density from 0 to 4.4 mW cm-2, the current value corresponding to the anti-ambipolar peak of the device (Ipeak) shifts from 0 to 4.3 nA, and the voltage value corresponding to the anti-ambipolar peak of the device (Vpeak) can shift from -7 to -5.67 V. These phenomena demonstrate that the charge neutrality point of the anti-ambipolar heterotransistor can be selectively varied with the change of laser power density. In addition, the aforementioned device possesses a high Ion/Ioff ratio of about 104 (405 nm, 4.4 mW cm-2) at 0 V. These properties indicate that our unique anti-ambipolar In2Se3&WSe2 heterotransistor can be employed in photo-triggered inverters for future optoelectronic circuits, and it has great potential to improve the integration of overall chip circuits by implementing optoelectronic logic functions in a unit.

15.
Nat Med ; 29(4): 973-981, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37055566

RESUMO

There is a paucity of high-quality evidence on the effectiveness and safety of salt reduction strategies, particularly for older people, who have the most to benefit but are at higher risk of adverse effects. Here, we conducted a clinical trial in which 48 residential elderly care facilities in China (1,612 participants including 1,230 men and 382 women, 55 years or older) were cluster-randomized using a 2 × 2 factorial design to provision of salt substitute (62.5% NaCl and 25% KCl) versus usual salt and to a progressively restricted versus usual supply of salt or salt substitute for 2 years. Salt substitute compared with usual salt lowered systolic blood pressure (-7.1 mmHg, 95% confidence interval (CI) -10.5 to -3.8), meeting the primary outcome of the trial, whereas restricted supply compared with usual supply of salt or salt substitute had no effect on systolic blood pressure. Salt substitute also lowered diastolic blood pressure (-1.9 mmHg, 95% CI -3.6 to -0.2) and resulted in fewer cardiovascular events (hazard ratio (HR) 0.60, 95% CI 0.38-0.96), but had no effect on total mortality (HR 0.84, 95% CI 0.63-1.13). From a safety standpoint, salt substitute increased mean serum potassium and led to more frequent biochemical hyperkalemia, but was not associated with adverse clinical outcomes. In contrast, salt restriction had no effect on any study outcome. The results of this trial indicate that use of salt substitute, but not efforts to restrict salt supply, may achieve blood pressure lowering and deliver health benefits to residents of elderly care facilities in China. Clinicaltrials.gov registration: NCT03290716.


Assuntos
Hipertensão , Masculino , Humanos , Feminino , Idoso , Pressão Sanguínea , Hipertensão/complicações , Cloreto de Sódio/farmacologia , Cloreto de Sódio na Dieta/efeitos adversos , China/epidemiologia
16.
Front Pediatr ; 11: 1091532, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937983

RESUMO

Neurodevelopmental disorders (NDDs) have heterogeneity in both clinical characteristics and genetic factors. EBF3 is a recently discovered gene associated with a syndromic form of NDDs characterized by hypotonia, ataxia and facial features. In this study, we report twelve unrelated individuals with EBF3 variants using next-generation sequencing. Five missense variants (four novel variants and one known variant) and seven copy number variations (CNVs) of EBF3 gene were identified. All of these patients exhibited developmental delay/intellectual disability. Ataxia was observed in 33% (6/9) of the patients, and abnormal muscle tone was observed in 55% (6/11) of the patients. Aberrant MRI reports were noted in 64% (7/11) of the patients. Four novel missense variants were all located in the DNA-binding domain. The pathogenicity of these variants was validated by in vitro experiments. We found that the subcellular protein localization of the R152C and F211L mutants was changed, and the distribution pattern of the R163G mutant was changed from even to granular. Luciferase assay results showed that the four EBF3 mutants' transcriptional activities were all significantly decreased (p < 0.01). Our study further expanded the gene mutation spectrum of EBF3-related NDD.

17.
J Asian Nat Prod Res ; 25(5): 411-421, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35880466

RESUMO

Three previously undescribed aromatic diglycosides (1, 5, and 8) and six known analogs (2-4, 6, 7, and 9) were isolated from the roots and rhizomes of Sophora tonkinensis Gagnep. Their structures were elucidated by detailed spectroscopic analysis. The absolute configuration of compound 8 was determined by comparing the experimental and TDDFT calculated ECD spectra of 8 and aglycone 8a. Furthermore, a multistep conformer filtering procedure for TDDFT calculation of flexible glycoside was proposed, which afforded high accuracy with acceptable computing cost in determining the absolute configuration of glycosides using quantum calculated ECD.


Assuntos
Glicosídeos , Sophora , Sophora/química , Rizoma/química , Raízes de Plantas/química
18.
Angew Chem Int Ed Engl ; 62(2): e202208451, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36268649

RESUMO

Current action mechanisms for aptamer-based therapeutics depend on occupancy-driven pharmacology to mediate protein functions. We report a new mechanism where aptamers leverage cellular proteasomal degradation system to degrade proteins for cancer treatment. A DNA aptamer (hereinafter referred to as c-Met-Ap) binds to the extracellular domain of mesenchymal-epithelial transition factor (c-Met) and selectively induces c-Met phosphorylation at Y1003 and Y1349. The phosphorylation of Y1003 recruits E3 ubiquitin ligase casitas B-lineage lymphoma, causing c-Met ubiquitination and degradation in the proteasome. Furthermore, c-Met-Ap can induce a decrease in the heterodimeric partner proteins of c-Met and the downstream effector proteins in the c-Met signal axis, effectively inhibiting tumor growth in A549 tumor-bearing BALB/c mice. Our study uncovers a novel, actionable mechanism for aptamer therapeutics and opens a new avenue for developing highly efficient anticancer drugs.


Assuntos
Complexo de Endopeptidases do Proteassoma , Ubiquitina-Proteína Ligases , Camundongos , Animais , Complexo de Endopeptidases do Proteassoma/metabolismo , Citoplasma/metabolismo , Ubiquitinação , Ubiquitina-Proteína Ligases/metabolismo , Fosforilação
19.
Org Lett ; 25(9): 1343-1347, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36583556

RESUMO

Two novel helical heteronanographenes bearing a [6]helicene unit (3a and 5a) have been synthesized, and their molecular structures are unambiguously determined via single-crystal X-ray diffraction analyses. Density functional theory calculations suggest that the as-prepared compounds have isomerization barriers of 29.02 kcal/mol for 3a and 34.07 kcal/mol for 5a, respectively. Optical enantiomers of 5a exhibit appealing chiroptical properties.

20.
Diabetes ; 72(3): 348-361, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36508222

RESUMO

Dysregulated lipid droplet accumulation has been identified as one of the main contributors to liver steatosis during nonalcoholic fatty liver disease (NAFLD). However, the underlying molecular mechanisms for excessive lipid droplet formation in the liver remain largely unknown. In the current study, hepatic E4 promoter-binding protein 4 (E4BP4) plays a critical role in promoting lipid droplet formation and liver steatosis in a high-fat diet (HFD)-induced NAFLD mouse model. Hepatic E4bp4 deficiency (E4bp4-LKO) protects mice from HFD-induced liver steatosis independently of obesity and insulin resistance. Our microarray study showed a markedly reduced expression of lipid droplet binding genes, such as Fsp27, in the liver of E4bp4-LKO mice. E4BP4 is both necessary and sufficient to activate Fsp27 expression and lipid droplet formation in primary mouse hepatocytes. Overexpression of Fsp27 increased lipid droplets and triglycerides in E4bp4-LKO primary mouse hepatocytes and restored hepatic steatosis in HFD-fed E4bp4-LKO mice. Mechanistically, E4BP4 enhances the transactivation of Fsp27 by CREBH in hepatocytes. Furthermore, E4BP4 is modified by SUMOylation, and HFD feeding induces deSUMOylation of hepatic E4BP4. SUMOylation of five lysine residues of E4BP4 is critical for the downregulation of Fsp27 and lipid droplets by cAMP signaling in hepatocytes. Taken together, this study revealed that E4BP4 drives liver steatosis in HFD-fed mice through its regulation of lipid droplet binding proteins. Our study also highlights the critical role of deSUMOylation of hepatic E4BP4 in promoting NAFLD.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica , Dieta Hiperlipídica , Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Hepatócitos/metabolismo , Gotículas Lipídicas/metabolismo , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fatores de Transcrição/metabolismo
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