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1.
Science ; 384(6701): eadk5382, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38870290

RESUMO

Polycystic ovary syndrome (PCOS), a prevalent reproductive disorder in women of reproductive age, features androgen excess, ovulatory dysfunction, and polycystic ovaries. Despite its high prevalence, specific pharmacologic intervention for PCOS is challenging. In this study, we identified artemisinins as anti-PCOS agents. Our finding demonstrated the efficacy of artemisinin derivatives in alleviating PCOS symptoms in both rodent models and human patients, curbing hyperandrogenemia through suppression of ovarian androgen synthesis. Artemisinins promoted cytochrome P450 family 11 subfamily A member 1 (CYP11A1) protein degradation to block androgen overproduction. Mechanistically, artemisinins directly targeted lon peptidase 1 (LONP1), enhanced LONP1-CYP11A1 interaction, and facilitated LONP1-catalyzed CYP11A1 degradation. Overexpression of LONP1 replicated the androgen-lowering effect of artemisinins. Our data suggest that artemisinin application is a promising approach for treating PCOS and highlight the crucial role of the LONP1-CYP11A1 interaction in controlling hyperandrogenism and PCOS occurrence.


Assuntos
Proteases Dependentes de ATP , Artemisininas , Enzima de Clivagem da Cadeia Lateral do Colesterol , Proteínas Mitocondriais , Síndrome do Ovário Policístico , Animais , Feminino , Humanos , Camundongos , Ratos , Androgênios/metabolismo , Artemisininas/uso terapêutico , Artemisininas/farmacologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Modelos Animais de Doenças , Hiperandrogenismo/tratamento farmacológico , Hiperandrogenismo/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Ovário/efeitos dos fármacos , Ovário/metabolismo , Síndrome do Ovário Policístico/tratamento farmacológico , Proteólise , Camundongos Endogâmicos C57BL , Adulto Jovem , Adulto , Ratos Sprague-Dawley , Proteases Dependentes de ATP/genética , Proteases Dependentes de ATP/metabolismo
2.
Mol Metab ; 81: 101891, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307386

RESUMO

OBJECTIVE: Brown adipose tissue (BAT) development and function are essential for maintaining energy balance. However, the key factors that specifically regulate brown adipogenesis require further identification. Here, we demonstrated that the nuclear receptor subfamily 2 group F member 6 (NR2F6) played a pivotal role in brown adipogenesis and energy homeostasis. METHODS: We examined the differentiation of immortalized brown adipocytes and primary brown adipocytes when NR2F6 were deleted, and explored the mechanism through which NR2F6 regulated adipogenesis using ChIP-qPCR in vitro. Male wild type (WT) and Pdgfra-Cre-mediated deletion of Nr2f6 in preadipocytes (NR2F6-PKO) mice were fed with high fat diet (HFD) for 12 weeks, and adiposity, glucose intolerance, insulin resistance and inflammation were assessed. RESULTS: NR2F6 exhibited abundant expression in BAT, while its expression was minimal in white adipose tissue (WAT). Within BAT, NR2F6 was highly expressed in preadipocytes, experienced a transient increase in the early stage of brown adipocyte differentiation, and significantly decreased in the mature adipocytes. Depletion of NR2F6 in preadipocytes inhibited brown adipogenesis, caused hypertrophy of brown adipocytes, and impaired thermogenic function of BAT, but without affecting WAT development. NR2F6 transcriptionally regulated PPARγ expression to promote adipogenic process in brown adipocytes. Loss of NR2F6 in preadipocytes led to increased susceptibility to diet-induced metabolic disorders. CONCLUSIONS: Our findings unveiled NR2F6 as a novel key regulator of brown adipogenesis, potentially opening up new avenues for maintaining metabolic homeostasis by targeting NR2F6.


Assuntos
Adipócitos Marrons , Tecido Adiposo Marrom , Animais , Masculino , Camundongos , Adipócitos Marrons/metabolismo , Adipogenia , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Homeostase
3.
Proc Natl Acad Sci U S A ; 120(33): e2305717120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549287

RESUMO

Great progress has been made in identifying positive regulators that activate adipocyte thermogenesis, but negative regulatory signaling of thermogenesis remains poorly understood. Here, we found that cardiotrophin-like cytokine factor 1 (CLCF1) signaling led to loss of brown fat identity, which impaired thermogenic capacity. CLCF1 levels decreased during thermogenic stimulation but were considerably increased in obesity. Adipocyte-specific CLCF1 transgenic (CLCF1-ATG) mice showed impaired energy expenditure and severe cold intolerance. Elevated CLCF1 triggered whitening of brown adipose tissue by suppressing mitochondrial biogenesis. Mechanistically, CLCF1 bound and activated ciliary neurotrophic factor receptor (CNTFR) and augmented signal transducer and activator of transcription 3 (STAT3) signaling. STAT3 transcriptionally inhibited both peroxisome proliferator-activated receptor-γ coactivator (PGC) 1α and 1ß, which thereafter restrained mitochondrial biogenesis in adipocytes. Inhibition of CNTFR or STAT3 could diminish the inhibitory effects of CLCF1 on mitochondrial biogenesis and thermogenesis. As a result, CLCF1-TG mice were predisposed to develop metabolic dysfunction even without external metabolic stress. Our findings revealed a brake signal on nonshivering thermogenesis and suggested that targeting this pathway could be used to restore brown fat activity and systemic metabolic homeostasis in obesity.


Assuntos
Adipócitos Marrons , Biogênese de Organelas , Animais , Camundongos , Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/metabolismo , Homeostase , Obesidade/genética , Obesidade/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Termogênese/fisiologia
4.
Phytochemistry ; 214: 113801, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37499851

RESUMO

The characteristic 1H NMR signals (H-7 and H2-9) are significant parameters that have been widely used to assess the relative configuration of H-7 and H-8 of 8,4'-oxyneolignans. However, many usual 8,4'-oxyneolignans cannot be accurately determined by existing NMR methods and no research considering their limitations was performed until now. In this study, the application scope of NMR methods was comprehensively studied and the ΔδH9a-H9b methods have been extended to solve the majority of configuration determination difficulties. The accuracy of extended NMR methods was verified by anisotropic NMR (RCSA measurements), NMR calculation and diverse statistical analysis (MAEΔΔδ, CP3 and DP4+). Furthermore, the theoretical conformational analysis was performed to investigate the inherent limitations of existing NMR methods. This study could provide a valuable reference for determining the relative configuration of H-7 and H-8 in 8,4'-oxyneolignans and the relative configuration of 23 recently reported 8,4'-oxyneolignan derivatives should be reassigned as well.


Assuntos
Estrutura Molecular , Estudos Retrospectivos , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina , Espectroscopia de Ressonância Magnética/métodos , Conformação Molecular
5.
Materials (Basel) ; 16(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37109853

RESUMO

In the present study, the sputtered aluminum nitride (AlN) films were processed in a reactive pulsed DC magnetron system. We applied a total of 15 different design of experiments (DOEs) on DC pulsed parameters (reverse voltage, pulse frequency, and duty cycle) with Box-Behnken experimental method and response surface method (RSM) to establish a mathematical model by experimental data for interpreting the relationship between independent and response variables. For the characterization of AlN films on the crystal quality, microstructure, thickness, and surface roughness, X-ray diffraction (XRD), atomic force microscopy (AFM), and field emission-scanning electron microscopy (FE-SEM) were utilized. AlN films have different microstructures and surface roughness under different pulse parameters. In addition, in-situ optical emission spectroscopy (OES) was employed to monitor the plasma in real-time, and its data were analyzed by principal component analysis (PCA) for dimensionality reduction and data preprocessing. Through the CatBoost modeling and analysis, we predicted results from XRD in full width at half maximum (FWHM) and SEM in grain size. This investigation identified the optimal pulse parameters for producing high-quality AlN films as a reverse voltage of 50 V, a pulse frequency of 250 kHz, and a duty cycle of 80.6061%. Additionally, a predictive CatBoost model for obtaining film FWHM and grain size was successfully trained.

6.
J Agric Food Chem ; 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36786443

RESUMO

Stigma maydis (corn silk) (S. maydis) is a food-based by-product of maize and possesses great nutritional and pharmaceutical value. This study aimed to explore bioactive components from S. maydis. By the guidance of bioactivity-guided approach and Global Natural Products Social (GNPS) molecular networking, 12 terpenoids were discovered from S. maydis. The structures of 11 undescribed compounds (1-11) were determined by detailed spectroscopic analyses, single-crystal X-ray diffraction analysis, specific rotation calculations, electronic circular dichroism (ECD) calculations, and NMR calculations. The neuroprotective and acetylcholinesterase (AChE) inhibitory effects of 1-12 were examined, and most of them showed significant or moderate activities. The underlying neuroprotective mechanism of 4 and 5 was revealed by Hoechst 33258, AO-EB, and JC-1 staining assays. This work illustrated the potential of S. maydis as a prospective natural source of bioactive compounds in food and pharmaceutical industries.

7.
Nat Prod Res ; 37(5): 835-839, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35736954

RESUMO

Corn silk (Stigma maydis), being the styles and stigmas of maize, is a famous traditional medicine and functional tea in China. Research into the chemical composition of corn silk led to the identification of an unreported flavone (1, silkone A), accompanying with three known flavonoids (2-4). And their structures were elucidated through comprehensive spectroscopic analysis. Each obtained compound was evaluated for antioxidant capacity by DPPH, ABTS and FRAP assays. As a result, all tested compounds exhibited stronger radicals scavenging activities than Trolox in ABTS radical assay and displayed relatively weak antioxidant capacity in the other two experiments. Tyrosinase inhibitory activities of compounds 1-4 were also investigated, and compounds 3 and 4 demonstrated moderate inhibitory activities to tyrosinase with IC50 values of 0.49 and 0.21 mM, respectively, which was further investigated through molecular docking calculation. These results may contribute to the development of novel antioxidants and tyrosinase inhibitors from corn silk.


Assuntos
Antioxidantes , Flavonoides , Antioxidantes/química , Flavonoides/química , Zea mays/química , Monofenol Mono-Oxigenase , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Seda
8.
Phytochemistry ; 204: 113468, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36191659

RESUMO

Investigation of the whole plant of Daphne gemmata E. Pritz. ex Diels (Thymelaeaceae) using molecular networking coupled to Network Annotation Propagation (NAP) and unsupervised substructure annotation (MS2LDA) led to the discovery of five tigliane diterpenoids, 14 guaiane sesquiterpenoids, one rhamnofolane diterpenoid and three carotene sesquiterpenoids. The structures of the eight undescribed compounds, daphnorbol A and daphnegemmatoids A-G, were characterized by detailed spectroscopic analyses, NMR and ECD calculations, application of Snatzke's method and single-crystal X-ray diffraction analysis. All isolated compounds were evaluated for their cytotoxic activities against HepG2, A549, and MCF-7 cells by MTT assay. Daphnorbol A exhibited significant cytotoxic activity against HepG2 and A549 cells with IC50 values of 4.06 µM and 6.35 µM, respectively. Prostratin showed potent cytotoxic activity against HepG2 and A549 cells with IC50 values of 6.06 µM and 5.45 µM, respectively. Further Hoechst 33,258 and AO-EB staining assays indicated that daphnorbol A and prostratin could induce apoptosis in HepG2 and A549 cells.

9.
Diabetes ; 71(9): 1862-1879, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35709007

RESUMO

Brown and beige adipocytes dissipate energy in a nonshivering thermogenesis manner, exerting beneficial effects on metabolic homeostasis. CHCHD10 is a nuclear-encoded mitochondrial protein involved in cristae organization; however, its role in thermogenic adipocytes remains unknown. We identify CHCHD10 as a novel regulator for adipocyte thermogenesis. CHCHD10 is dramatically upregulated during thermogenic adipocyte activation by PPARγ-PGC1α and positively correlated with UCP1 expression in adipose tissues from humans and mice. We generated adipocyte-specific Chchd10 knockout mice (Chchd10-AKO) and found that depleting CHCHD10 leads to impaired UCP1-dependent thermogenesis and energy expenditure in the fasting state, with no effect in the fed state. Lipolysis in adipocytes is disrupted by CHCHD10 deficiency, while augmented lipolysis through ATGL overexpression recovers adipocyte thermogenesis in Chchd10-AKO mice. Consistently, overexpression of Chchd10 activates thermogenic adipocytes. Mechanistically, CHCHD10 deficiency results in the disorganization of mitochondrial cristae, leading to impairment of oxidative phosphorylation complex assembly in mitochondria, which in turn inhibits ATP generation. Decreased ATP results in downregulation of lipolysis by reducing nascent protein synthesis of ATGL, thereby suppressing adipocyte thermogenesis. As a result, Chchd10-AKO mice are prone to develop high-fat diet-induced metabolic disorders. Together, our findings reveal an essential role of CHCHD10 in regulating lipolysis and the thermogenic program in adipocytes.


Assuntos
Adipócitos Bege , Adipócitos Marrons , Lipólise , Proteínas Mitocondriais , Termogênese , Trifosfato de Adenosina/metabolismo , Adipócitos Bege/metabolismo , Adipócitos Marrons/metabolismo , Animais , Humanos , Lipólise/genética , Camundongos , Camundongos Knockout , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
10.
J Biol Chem ; 298(2): 101544, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34971706

RESUMO

Uncontrolled gluconeogenesis results in elevated hepatic glucose production in type 2 diabetes (T2D). The small ubiquitin-related modifier (SUMO)-specific protease 2 (SENP2) is known to catalyze deSUMOylation of target proteins, with broad effects on cell growth, signal transduction, and developmental processes. However, the role of SENP2 in hepatic gluconeogenesis and the occurrence of T2D remain unknown. Herein, we established SENP2 hepatic knockout mice and found that SENP2 deficiency could protect against high-fat diet-induced hyperglycemia. Pyruvate- or glucagon-induced elevation in blood glucose was attenuated by disruption of SENP2 expression, whereas overexpression of SENP2 in the liver facilitated high-fat diet-induced hyperglycemia. Using an in vitro assay, we showed that SENP2 regulated hepatic glucose production. Mechanistically, the effects of SENP2 on gluconeogenesis were found to be mediated by the cellular fuel sensor kinase, 5'-AMP-activated protein kinase alpha (AMPKα), which is a negative regulator of gluconeogenesis. SENP2 interacted with and deSUMOylated AMPKα, thereby promoting its ubiquitination and reducing its protein stability. Inhibition of AMPKα kinase activity dramatically reversed impaired hepatic gluconeogenesis and reduced blood glucose levels in SENP2-deficient mice. Our study highlights the novel role of hepatic SENP2 in regulating gluconeogenesis and furthers our understanding of the pathogenesis of T2D.


Assuntos
Proteínas Quinases Ativadas por AMP , Cisteína Endopeptidases , Diabetes Mellitus Tipo 2 , Hiperglicemia , Sumoilação , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Glicemia/metabolismo , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Gluconeogênese , Glucose/metabolismo , Hiperglicemia/metabolismo , Fígado/metabolismo , Camundongos , Peptídeo Hidrolases/metabolismo
11.
J Asian Nat Prod Res ; 24(8): 703-712, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34585635

RESUMO

Ten compounds (1-10) including four new compounds (1-4) and six known compounds (5-10) were isolated from Solanum nigrum. Their structures were elucidated on the basis of spectroscopic data, gauge-including atomic orbital (GIAO) calculation of NMR data, DP4+ probability analysis and comparison of their experimental and calculated electronic circular dichroism (ECD) spectral data. All the isolated compounds were tested for their neuroprotective activities against H2O2-induced damage in SH-SY5Y cells. Among them, compounds 1, 5 and 7 displayed moderate neuroprotective effects.


Assuntos
Neuroblastoma , Fármacos Neuroprotetores , Solanum nigrum , Humanos , Peróxido de Hidrogênio/farmacologia , Estrutura Molecular , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia
12.
Bioorg Chem ; 116: 105356, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34560562

RESUMO

Two undescribed ent-abietane-type diterpenoid dimers with nonacyclic backbone formed by intermolecular [4 + 2] cycloaddition into a spirocyclic skeleton, bisfischoids A (1) and B (2), along with a known one fischdiabietane A (3), were identified from Euphorbia fischeriana Steud. Their structures were elucidated by extensive spectroscopic analysis, ECD and NMR calculation combined with DP4+ probability analysis, as well as X-ray diffraction. The anti-inflammatory potential of dimers 1-3 were examined using their inhibitory effects on soluble epoxide hydrolase (sEH), which revealed that 1 and 2 exhibited promising activities with inhibition constant (Ki) of 3.20 and 1.95 µM, respectively. Further studies of molecular docking and molecular dynamics indicated that amino acid residue Tyr343 in the catalytic cavity of sEH was the key site for their inhibitory function.


Assuntos
Anti-Inflamatórios/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Epóxido Hidrolases/antagonistas & inibidores , Euphorbia/química , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Epóxido Hidrolases/metabolismo , Humanos , Medicina Tradicional Chinesa , Estrutura Molecular , Relação Estrutura-Atividade
13.
Hepatology ; 74(4): 1864-1883, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33934381

RESUMO

BACKGROUND AND AIMS: NAFLD, characterized by aberrant triglyceride accumulation in liver, affects the metabolic remodeling of hepatic and nonhepatic tissues by secreting altered hepatokines. Small ubiquitin-related modifier (SUMO)-specific protease 2 (SENP2) is responsible for de-SUMOylation of target protein, with broad effects on cell growth, signal transduction, and developmental processes. However, the role of SENP2 in hepatic metabolism remains unclear. APPROACH AND RESULTS: We found that SENP2 was the most dramatically increased SENP in the fatty liver and that its level was modulated by fed/fasted conditions. To define the role of hepatic SENP2 in metabolic regulation, we generated liver-specific SENP2 knockout (Senp2-LKO) mice. Senp2-LKO mice exhibited resistance to high-fat diet-induced hepatic steatosis and obesity. RNA-sequencing analysis showed that Senp2 deficiency up-regulated genes involved in fatty acid oxidation and down-regulated genes in lipogenesis in the liver. Additionally, ablation of hepatic SENP2 activated thermogenesis of adipose tissues. Improved energy homeostasis of both the liver and adipose tissues by SENP2 disruption prompted us to detect the hepatokines, with FGF21 identified as a key factor markedly elevated in Senp2-LKO mice that maintained metabolic homeostasis. Loss of FGF21 obviously reversed the positive effects of SENP2 deficiency on metabolism. Mechanistically, by screening transcriptional factors of FGF21, peroxisome proliferator-activated receptor alpha (PPARα) was defined as the mediator for SENP2 and FGF21. SENP2 interacted with PPARα and deSUMOylated it, thereby promoting ubiquitylation and subsequent degradation of PPARα, which in turn inhibited FGF21 expression and fatty acid oxidation. Consistently, SENP2 overexpression in liver facilitated development of metabolic disorders. CONCLUSIONS: Our finding demonstrated a key role of hepatic SENP2 in governing metabolic balance by regulating liver-adipose tissue crosstalk, linking the SUMOylation process to metabolic regulation.


Assuntos
Tecido Adiposo/metabolismo , Cisteína Endopeptidases/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , PPAR alfa/metabolismo , Animais , Cisteína Endopeptidases/metabolismo , Dieta Hiperlipídica , Metabolismo Energético/genética , Ácidos Graxos/metabolismo , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Humanos , Lipogênese/genética , Síndrome Metabólica/genética , Síndrome Metabólica/metabolismo , Camundongos , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/genética , Obesidade/metabolismo , Sumoilação , Termogênese/genética , Ubiquitinação
14.
Nat Prod Res ; 35(18): 3142-3145, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31709827

RESUMO

A new monoterpene-lactone (1) along with five known compounds (2-6) were isolated from corn silk. The structure of the new compound was elucidated based on comprehensive spectroscopic analyses and quantum chemical calculations of electronic circular dichroism (ECD) curves. All compounds were evaluated for their neuroprotective effects against H2O2-induced damage in human dopaminergic neuroblastoma cells (SH-SY5Y). As a result, compound 1 exhibited weak neuroprotective activity.


Assuntos
Lactonas/farmacologia , Monoterpenos/farmacologia , Fármacos Neuroprotetores , Zea mays/química , Linhagem Celular Tumoral , Humanos , Peróxido de Hidrogênio , Lactonas/isolamento & purificação , Estrutura Molecular , Monoterpenos/isolamento & purificação , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia
15.
J Environ Manage ; 258: 110052, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31929078

RESUMO

The atmospheric pollution has been the public attention in recent years. In order to better coordinate economic development and atmospheric environmental management, China introduced the concept of atmospheric environmental capacity (AEC). The remaining atmospheric environmental capacity (RAEC) calculated by existing atmospheric pollution sources and AEC is an important basis for regional development and environmental protection. The RAEC of the high-pollution risk suburb of Chengdu in 2015 was estimated by the single-box model and analyzed on multiple time scales. The results show that the RAEC of SO2 and NO2 in this region is 3299 t/a and 2849 t/a, respectively under the annual time scale. However, in the daily time scale, the RAEC of NO2 is negative for 3 days, that is, there are 3 days with serious air pollution. Therefore, it is not appropriate to plan the industrial area only by relying on annual RAEC. Especially, RAEC displays inter-seasonal and monthly variability. On the one hand, in plain areas with low wind speed and little change in wind direction, achieving the prediction of atmospheric mixing layer height could give early warning of atmospheric pollution events. On the other hand, different management measures are taken on different time scales. On a long timescale, the regional energy structure should be optimized. On seasonal and monthly time scales, the production plans should be adapted to RAEC. On the daily time scale, it mainly deals with the serious atmospheric pollution accident timely.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , China , Monitoramento Ambiental , Material Particulado , Estações do Ano
16.
Nat Prod Res ; 34(10): 1352-1359, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-30417665

RESUMO

As a part of our ongoing search for neuroprotective compounds from natural products, two new iridoid glycosides, vibsansuspenside A-B (1-2), along with five known terpenoids (3-7), were isolated from the dry leaves of Viburnum odoratissimum. Their chemical structures were well determined by means of NMR spectroscopic data as well as HRESIMS analysis. All compounds were detected for their neuroprotective effects against H2O2-induced damage in human dopaminergic neuroblastoma cells (SH-SY5Y). Among them, compound 3 displayed the most potent neuroprotective ability, and further investigation by Annexin V/PI and Western blot analysis demonstrated that compound 3 could protect SH-SY5Y cells from oxidative damage through inhibiting cell apoptosis.[Formula: see text].


Assuntos
Fármacos Neuroprotetores/isolamento & purificação , Folhas de Planta/química , Terpenos/isolamento & purificação , Viburnum/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Glicosídeos/isolamento & purificação , Humanos , Peróxido de Hidrogênio/farmacologia , Estrutura Molecular , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Fármacos Neuroprotetores/farmacologia , Terpenos/análise , Terpenos/farmacologia
17.
Fitoterapia ; 141: 104448, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31816344

RESUMO

Five undescribed macrocarpene-type sesquiterpenes (1-5), along with a known analogue (6) were isolated from the crude extract of stigma maydis. The structures of these compounds were elucidated based on comprehensive spectroscopic analyses together with quantum chemical calculations of 13C NMR data and electronic circular dichroism (ECD) curves. All isolated compounds were tested for their neuroprotective effects against the injury of human neuroblastoma SH-SY5Y cells induced by H2O2. Among them, compounds 3 (65.89%) and 5 (64.38%) showed moderate neuroprotective activity at 50 µM.


Assuntos
Flores/química , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Zea mays/química , Linhagem Celular Tumoral , China , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Peróxido de Hidrogênio , Estrutura Molecular , Neuroblastoma/tratamento farmacológico , Fármacos Neuroprotetores/química , Extratos Vegetais/química , Sesquiterpenos/química
18.
Fitoterapia ; 138: 104356, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31520649

RESUMO

Five pairs of enantiomeric compounds (1a/1b-5a/5b) including seven undescribed compounds (1a/1b-3a/3b, 4b) along with two known ones (. and .) have been isolated from corn silk (Stigma maydis). Racemic mixtures of these enantiomers were separated by HPLC with different types of chiral columns. Their structures were elucidated based on comprehensive spectroscopic analyses together with quantum chemical calculations of 13C NMR data and electronic circular dichroism (ECD) curves. All the isolates were evaluated for their inhibition ability of self-induced Aß1-42 aggregation. Among them, compounds 4a (88.36%), 4b (74.66%) and . (85.65%) showed stronger inhibitory activity than the positive control curcumin (61.90%). The different inhibition profiles of enantiomers 4a and 4b were explained by docking simulation studies.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Flores/química , Fragmentos de Peptídeos/antagonistas & inibidores , Compostos Fitoquímicos/farmacologia , Agregação Patológica de Proteínas/prevenção & controle , Zea mays/química , China , Simulação de Acoplamento Molecular , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação
19.
Planta Med ; 85(8): 648-656, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30974464

RESUMO

Four pairs of ß-carboline enantiomers (1A: /1B: -4A: /4B: ), 2 ß-carboline derivatives (5:  - 6: ) with a single enantiomeric configuration, together with 2 known achiral congeners (7:  - 8: ) were isolated from the stems of Picrasma quassioides. Their structures were elucidated on the basis of extensive spectroscopic analyses and quantum mechanical calculations. Compound 5: possesses a 4,5-seco ß-carboline framework and represents the first example of this type of ß-carboline alkaloids from nature. A possible biosynthetic pathway is proposed to generate the racemate 4: and the enantiomerically pure compounds 5: and 6: . All isolates were screened for their cytotoxicity against hepatocellular carcinoma Hep3B and HepG2 cells, which revealed that enantiomeric compounds 4A: and 4B: had distinctive effects in HepG2 cells. Further investigation showed that 4B: could induce apoptosis in HepG2 cells.


Assuntos
Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Carbolinas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Picrasma/química , Alcaloides/química , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Carbolinas/química , Carbolinas/farmacologia , Cromatografia , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Estrutura Molecular , Estereoisomerismo
20.
J Nat Prod ; 82(4): 714-723, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30917277

RESUMO

Quassinoids are a class of highly oxygenated degraded triterpenoids exclusively discovered from plants of the Simaroubaceae family. In this study, eight new (1-8) and 15 known quassinoids (9-23) were isolated from an extract of the stems of Picrasma quassioides. The structures were elucidated by spectroscopic analysis and electronic circular dichroism spectra combined with quantum chemical calculations. Compounds 4 and 5 represent the first examples of 18-nor-quassinoids from P. quassioides. All isolates were screened for their neuroprotective activities toward H2O2-induced cell damage in SH-SY5Y cells. Further study revealed that the potential protective activities of these compounds appeared to occur via the suppression of cell apoptosis and downregulation of caspase-3 activation.


Assuntos
Fármacos Neuroprotetores/farmacologia , Picrasma/química , Quassinas/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Linhagem Celular Tumoral , Humanos , Peróxido de Hidrogênio/toxicidade , Estrutura Molecular , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Espectroscopia de Prótons por Ressonância Magnética , Quassinas/química , Quassinas/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray
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