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1.
Epilepsia ; 65(1): 46-56, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37347512

RESUMO

OBJECTIVES: Although hemispheric surgeries are among the most effective procedures for drug-resistant epilepsy (DRE) in the pediatric population, there is a large variability in seizure outcomes at the group level. A recently developed HOPS score provides individualized estimation of likelihood of seizure freedom to complement clinical judgement. The objective of this study was to develop a freely accessible online calculator that accurately predicts the probability of seizure freedom for any patient at 1-, 2-, and 5-years post-hemispherectomy. METHODS: Retrospective data of all pediatric patients with DRE and seizure outcome data from the original Hemispherectomy Outcome Prediction Scale (HOPS) study were included. The primary outcome of interest was time-to-seizure recurrence. A multivariate Cox proportional-hazards regression model was developed to predict the likelihood of post-hemispheric surgery seizure freedom at three time points (1-, 2- and 5- years) based on a combination of variables identified by clinical judgment and inferential statistics predictive of the primary outcome. The final model from this study was encoded in a publicly accessible online calculator on the International Network for Epilepsy Surgery and Treatment (iNEST) website (https://hops-calculator.com/). RESULTS: The selected variables for inclusion in the final model included the five original HOPS variables (age at seizure onset, etiologic substrate, seizure semiology, prior non-hemispheric resective surgery, and contralateral fluorodeoxyglucose-positron emission tomography [FDG-PET] hypometabolism) and three additional variables (age at surgery, history of infantile spasms, and magnetic resonance imaging [MRI] lesion). Predictors of shorter time-to-seizure recurrence included younger age at seizure onset, prior resective surgery, generalized seizure semiology, FDG-PET hypometabolism contralateral to the side of surgery, contralateral MRI lesion, non-lesional MRI, non-stroke etiologies, and a history of infantile spasms. The area under the curve (AUC) of the final model was 73.0%. SIGNIFICANCE: Online calculators are useful, cost-free tools that can assist physicians in risk estimation and inform joint decision-making processes with patients and families, potentially leading to greater satisfaction. Although the HOPS data was validated in the original analysis, the authors encourage external validation of this new calculator.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Hemisferectomia , Espasmos Infantis , Criança , Humanos , Hemisferectomia/métodos , Espasmos Infantis/cirurgia , Estudos Retrospectivos , Fluordesoxiglucose F18 , Resultado do Tratamento , Epilepsia/diagnóstico por imagem , Epilepsia/cirurgia , Convulsões/diagnóstico , Convulsões/etiologia , Convulsões/cirurgia , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Imageamento por Ressonância Magnética , Eletroencefalografia
2.
Phytomedicine ; 117: 154907, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37295024

RESUMO

BACKGROUND: The diterpenoid alkaloids belong to a highly esteemed group of natural compounds, which display significant biological activities. It is a productive strategy to expand the chemical space of these intriguing natural compounds for drug discovery. METHODS: We prepared a series of new derivatives bearing diverse skeletons and functionalities from the diterpenoid alkaloids deltaline and talatisamine based on a diversity-oriented synthesis strategy. The anti-inflammatory activity of these derivatives was initially screened and evaluated by the release of nitric oxide (NO), tumor necrosis factor (TNF-α), and interleukin-6 (IL-6) in lipopolysaccharide (LPS)-activated RAW264.7 cells. Futhermore, the anti-inflammatory activity of the representative derivative 31a was validated in various inflammatory animal models, including phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mice ear edema, LPS-stimulated acute kidney injury, and collagen-induced arthritis (CIA). RESULTS: It was found that several derivatives were able to suppress the secretion of NO, TNF-α, and IL-6 in LPS-activated RAW264.7 cells. Compound 31a, one of the representative derivatives named as deltanaline, demonstrated the strongest anti-inflammatory effects in LPS-activated macrophages and three different animal models of inflammatory diseases by inhibiting nuclear factor kappa-B (NF-κB)/mitogen-activated protein kinase (MAPK) signaling and inducing autophagy. CONCLUSION: Deltanaline is a new structural compound derived from natural diterpenoid alkaloids, which may serve as a new lead compound for the treatment of inflammatory diseases.


Assuntos
Alcaloides , Diterpenos , Camundongos , Animais , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Anti-Inflamatórios/uso terapêutico , NF-kappa B/metabolismo , Alcaloides/farmacologia , Células RAW 264.7 , Diterpenos/farmacologia , Óxido Nítrico/metabolismo
3.
Front Pharmacol ; 14: 1118017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124193

RESUMO

Aberrant mitophagy has been identified as a driver for energy metabolism disorder in most cardiac pathological processes. However, finding effective targeted agents and uncovering their precise modulatory mechanisms remain unconquered. Fuzi, the lateral roots of Aconitum carmichaelii, shows unique efficacy in reviving Yang for resuscitation, which has been widely used in clinics. As a main cardiotonic component of Fuzi, mesaconine has been proven effective in various cardiomyopathy models. Here, we aimed to define a previously unrevealed cardioprotective mechanism of mesaconine-mediated restoration of obstructive mitophagy. The functional implications of mesaconine were evaluated in doxorubicin (DOX)-induced heart failure models. DOX-treated mice showed characteristic cardiac dysfunction, ectopic myocardial energy disorder, and impaired mitophagy in cardiomyocytes, which could be remarkably reversed by mesaconine. The cardioprotective effect of mesaconine was primarily attributed to its ability to promote the restoration of mitophagy in cardiomyocytes, as evidenced by elevated expression of PINK1, a key mediator of mitophagy induction. Silencing PINK1 or deactivating mitophagy could completely abolish the protective effects of mesaconine. Together, our findings suggest that the cardioprotective effects of mesaconine appear to be dependent on the activation of PINK1-induced mitophagy and that mesaconine may constitute a promising therapeutic agent for the treatment of heart failure.

4.
J Asian Nat Prod Res ; 25(9): 819-833, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36632044

RESUMO

This paper describes a rare phenomenon of multi-conformers caused by conformational change of A-ring in the C18- and C19- N-dealkyl diterpenoid alkaloids. The possible reasons for the generation of multiple conformational isomers are complex, which could be affected by the substituents at C-1, C-3, C-13, C-14, and C-15, pH, solvents, the intramolecular hydrogen bond between 1α-OCH3/1α-OH and N-H groups, acid-base treatment, preparation methods, and work-up procedures.


Assuntos
Aconitum , Alcaloides , Diterpenos , Alcaloides/química , Diterpenos/química , Aconitum/química , Estrutura Molecular
5.
Brain ; 146(6): 2389-2398, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36415957

RESUMO

More than half of adults with epilepsy undergoing resective epilepsy surgery achieve long-term seizure freedom and might consider withdrawing antiseizure medications. We aimed to identify predictors of seizure recurrence after starting postoperative antiseizure medication withdrawal and develop and validate predictive models. We performed an international multicentre observational cohort study in nine tertiary epilepsy referral centres. We included 850 adults who started antiseizure medication withdrawal following resective epilepsy surgery and were free of seizures other than focal non-motor aware seizures before starting antiseizure medication withdrawal. We developed a model predicting recurrent seizures, other than focal non-motor aware seizures, using Cox proportional hazards regression in a derivation cohort (n = 231). Independent predictors of seizure recurrence, other than focal non-motor aware seizures, following the start of antiseizure medication withdrawal were focal non-motor aware seizures after surgery and before withdrawal [adjusted hazard ratio (aHR) 5.5, 95% confidence interval (CI) 2.7-11.1], history of focal to bilateral tonic-clonic seizures before surgery (aHR 1.6, 95% CI 0.9-2.8), time from surgery to the start of antiseizure medication withdrawal (aHR 0.9, 95% CI 0.8-0.9) and number of antiseizure medications at time of surgery (aHR 1.2, 95% CI 0.9-1.6). Model discrimination showed a concordance statistic of 0.67 (95% CI 0.63-0.71) in the external validation cohorts (n = 500). A secondary model predicting recurrence of any seizures (including focal non-motor aware seizures) was developed and validated in a subgroup that did not have focal non-motor aware seizures before withdrawal (n = 639), showing a concordance statistic of 0.68 (95% CI 0.64-0.72). Calibration plots indicated high agreement of predicted and observed outcomes for both models. We show that simple algorithms, available as graphical nomograms and online tools (predictepilepsy.github.io), can provide probabilities of seizure outcomes after starting postoperative antiseizure medication withdrawal. These multicentre-validated models may assist clinicians when discussing antiseizure medication withdrawal after surgery with their patients.


Assuntos
Epilepsias Parciais , Epilepsia Generalizada , Epilepsia , Humanos , Adulto , Anticonvulsivantes/efeitos adversos , Recidiva Local de Neoplasia/tratamento farmacológico , Epilepsia/tratamento farmacológico , Epilepsia/cirurgia , Convulsões/tratamento farmacológico , Epilepsia Generalizada/tratamento farmacológico
6.
Alkaloids Chem Biol ; 87: 1-360, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35168778

RESUMO

The diterpenoid alkaloids are a family of extremely important natural products that have long been a research hotspot due to their myriad of intricate structures and diverse biological properties. This chapter systematically summarizes the past 11 years (2009-2019) of studies on the diterpenoid alkaloids, including the "so-called" atypical ones, covering the classification and biogenetic relationships, phytochemistry together with 444 new alkaloids covering 32 novel skeletons and the corrected structures, chemical reactions including conversion toward toxoids, synthetic studies, as well as biological activities. It should be noted that the synthetic studies, especially the total syntheses of various diterpenoid alkaloids, are for the first time reviewed in this treatise. This chapter, in combination with our four previous reviews in volumes 42, 59, 67, and 69, will present to the readers a more completed and updated profile of the diterpenoid alkaloids.


Assuntos
Alcaloides , Produtos Biológicos , Diterpenos , Estrutura Molecular
7.
Epilepsia ; 62(11): 2707-2718, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34510448

RESUMO

OBJECTIVE: This study was undertaken to determine whether the vertical parasagittal approach or the lateral peri-insular/peri-Sylvian approach to hemispheric surgery is the superior technique in achieving long-term seizure freedom. METHODS: We conducted a post hoc subgroup analysis of the HOPS (Hemispheric Surgery Outcome Prediction Scale) study, an international, multicenter, retrospective cohort study that identified predictors of seizure freedom through logistic regression modeling. Only patients undergoing vertical parasagittal, lateral peri-insular/peri-Sylvian, or lateral trans-Sylvian hemispherotomy were included in this post hoc analysis. Differences in seizure freedom rates were assessed using a time-to-event method and calculated using the Kaplan-Meier survival method. RESULTS: Data for 672 participants across 23 centers were collected on the specific hemispherotomy approach. Of these, 72 (10.7%) underwent vertical parasagittal hemispherotomy and 600 (89.3%) underwent lateral peri-insular/peri-Sylvian or trans-Sylvian hemispherotomy. Seizure freedom was obtained in 62.4% (95% confidence interval [CI] = 53.5%-70.2%) of the entire cohort at 10-year follow-up. Seizure freedom was 88.8% (95% CI = 78.9%-94.3%) at 1-year follow-up and persisted at 85.5% (95% CI = 74.7%-92.0%) across 5- and 10-year follow-up in the vertical subgroup. In contrast, seizure freedom decreased from 89.2% (95% CI = 86.3%-91.5%) at 1-year to 72.1% (95% CI = 66.9%-76.7%) at 5-year to 57.2% (95% CI = 46.6%-66.4%) at 10-year follow-up for the lateral subgroup. Log-rank test found that vertical hemispherotomy was associated with durable seizure-free progression compared to the lateral approach (p = .01). Patients undergoing the lateral hemispherotomy technique had a shorter time-to-seizure recurrence (hazard ratio = 2.56, 95% CI = 1.08-6.04, p = .03) and increased seizure recurrence odds (odds ratio = 3.67, 95% CI = 1.05-12.86, p = .04) compared to those undergoing the vertical hemispherotomy technique. SIGNIFICANCE: This pilot study demonstrated more durable seizure freedom of the vertical technique compared to lateral hemispherotomy techniques. Further studies, such as prospective expertise-based observational studies or a randomized clinical trial, are required to determine whether a vertical approach to hemispheric surgery provides superior long-term seizure outcomes.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Hemisferectomia , Criança , Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia/cirurgia , Hemisferectomia/métodos , Humanos , Projetos Piloto , Estudos Prospectivos , Estudos Retrospectivos , Convulsões/cirurgia , Resultado do Tratamento
8.
Epilepsia ; 62(5): 1064-1073, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33713438

RESUMO

OBJECTIVE: To develop and validate a model to predict seizure freedom in children undergoing cerebral hemispheric surgery for the treatment of drug-resistant epilepsy. METHODS: We analyzed 1267 hemispheric surgeries performed in pediatric participants across 32 centers and 12 countries to identify predictors of seizure freedom at 3 months after surgery. A multivariate logistic regression model was developed based on 70% of the dataset (training set) and validated on 30% of the dataset (validation set). Missing data were handled using multiple imputation techniques. RESULTS: Overall, 817 of 1237 (66%) hemispheric surgeries led to seizure freedom (median follow-up = 24 months), and 1050 of 1237 (85%) were seizure-free at 12 months after surgery. A simple regression model containing age at seizure onset, presence of generalized seizure semiology, presence of contralateral 18-fluoro-2-deoxyglucose-positron emission tomography hypometabolism, etiologic substrate, and previous nonhemispheric resective surgery is predictive of seizure freedom (area under the curve = .72). A Hemispheric Surgery Outcome Prediction Scale (HOPS) score was devised that can be used to predict seizure freedom. SIGNIFICANCE: Children most likely to benefit from hemispheric surgery can be selected and counseled through the implementation of a scale derived from a multiple regression model. Importantly, children who are unlikely to experience seizure control can be spared from the complications and deficits associated with this surgery. The HOPS score is likely to help physicians in clinical decision-making.


Assuntos
Epilepsia Resistente a Medicamentos/cirurgia , Hemisferectomia , Resultado do Tratamento , Idade de Início , Criança , Pré-Escolar , Estudos de Coortes , Epilepsia Resistente a Medicamentos/patologia , Epilepsia Resistente a Medicamentos/fisiopatologia , Feminino , Humanos , Lactente , Modelos Logísticos , Masculino , Prognóstico , Estudos Retrospectivos , Fatores de Risco
9.
Acc Chem Res ; 54(1): 22-34, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33351595

RESUMO

Three-dimensional cage-like natural products represent astounding and long-term challenges in the research endeavors of total synthesis. A central issue that synthetic chemists need to address lies in how to efficiently construct the polycyclic frameworks as well as to install the requisite substituent groups. The diterpenoid alkaloids that biogenetically originate from amination of diterpenes and diversify through late-stage skeletal reorganization belong to such a natural product category. As the characteristic components of the Aconitum and Delphinium species, these molecules display a rich array of biological activities, some of which are used as clinical drugs. More strikingly, their intricate and beautiful architectures have rendered the diterpenoid alkaloids elusive targets in the synthetic community. The successful preparation of these intriguing compounds relies on the development of innovative synthetic strategies.Our laboratory has explored the total synthesis of a variety of diterpenoid alkaloids and their biogenetically related diterpenes over the past decade. In doing so, we have accessed 6 different types of skeletons (atisine-, denudatine-, arcutane-, arcutine-, napelline-, and hetidine-type) and achieved the total synthesis of 6 natural products (isoazitine, dihydroajaconine, gymnandine, atropurpuran, arcutinine, and liangshanone). Strategically, an oxidative dearomatization/Diels-Alder (OD/DA) cycloaddition sequence was widely employed in our synthesis to form the ubiquitous [2.2.2]-bicyclic ring unit and its related ring-distorted derivatives in these complex target molecules. This protocol, in combination with additional bond-forming key steps, allowed us to prepare the corresponding polycyclic alkaloids and a biogenetically associated diterpene. For example, bioinspired C-H activation, aza-pinacol, and aza-Prins cyclizations were used toward a unified approach to the atisine-, denudatine-, and hetidine-type alkaloids via ajaconine intermediates in our first work. To pursue the synthesis of atropurpuran and related arcutine alkaloids, we harnessed a ketyl-olefin radical cyclization to assemble the carbocycle and an aza-Wacker cyclization to construct the unusual pyrrolidine ring. Furthermore, a one-pot alkene cleavage/Mannich cyclization tactic, sequential Robinson annulation, and intramolecular aldol addition were developed, which facilitated the formation of the napelline alkaloid scaffold and the first total synthesis of liangshanone. Finally, the utility of the Mannich cyclization and enyne cycloisomerization reactions allowed for access to the highly functionalized A/E and C/D ring fragments of aconitine (regarded as the "Holy Grail" of diterpenoid alkaloids). This Account provides insight into our synthetic designs and approaches used toward the synthesis of diterpenoid alkaloids and relevant diterpenes. These endeavors lay a foundation for uncovering the biological profiles of associated molecules and also serve as a reference for preparing other three-dimensionally fascinating natural products.


Assuntos
Alcaloides/síntese química , Produtos Biológicos/síntese química , Diterpenos/química , Alcaloides/química , Produtos Biológicos/química , Compostos Bicíclicos com Pontes/síntese química , Compostos Bicíclicos com Pontes/química , Ciclização , Reação de Cicloadição , Diterpenos/síntese química , Conformação Molecular , Oxirredução , Estereoisomerismo
10.
Nat Prod Bioprospect ; 11(1): 15-20, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32960403

RESUMO

This review summarizes the process of the discovery, research, and development of a cardioactive component, mesaconine, from the lateral roots of Aconitum carmichaelii ("Fu Zi"). To date, pre-clinical showed that mesaconine is a novel type of cardiotonic lead drug with relatively high potency, low toxicity, and a new mechanism.

11.
Angew Chem Int Ed Engl ; 59(52): 23609-23614, 2020 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-32902096

RESUMO

The first total synthesis of liangshanone, a hexacyclic ent-kaurane diterpenoid alkaloid, has been completed. Its intricate cagelike framework was assembled through several key transformations, including an oxidative dearomatization/Diels-Alder (OD/DA) cycloaddition sequence, a tandem alkene cleavage/Mannich cyclization, a Robinson-type annulation, and an intramolecular aldol reaction. Notably, an organocatalytic enantioselective α-hydroxymethylation process allowed the preparation of an enantiomerically enriched tricyclic intermediate that should enable asymmetric access to the target natural product.

12.
Water Sci Technol ; 80(8): 1413-1420, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31961804

RESUMO

In this study, a high-concentration simulated organic wastewater, made by dissolving methyl violet in water, was degraded using dielectric barrier discharge (DBD) plasma generated in air and O2 respectively. The decoloration rate and chemical oxygen demand (COD) of wastewater were evaluated during plasma treatments with the initial concentration of methyl violet of 300 mg L-1. Results showed that the highest decoloration rate of around 100% within 10 min and the highest COD decrease of 33% within 60 min could be achieved with the O2 plasma treatment at the discharge voltage of 10 kV, while air plasma treatment showed lower efficiency in decolorizing the methyl violet solution and lower COD decrease (24%) after 60 min treatment. UV-Vis spectroscopy and chemical analysis of generated by-products during the plasma-enabled degradation process revealed that the methyl violet molecules could be completely decomposed into some refractory organics in the solution. Based on the experimental results and literature review, a pathway of methyl violet degradation attributed to energetic electrons and highly reactive species generated by DBD was proposed.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Análise da Demanda Biológica de Oxigênio , Violeta Genciana , Águas Residuárias
13.
Nat Prod Commun ; 12(3): 329-330, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30549877

RESUMO

Continuous investigations of the roots of Aconitum nagarum var. lasiandrum led to the isolation of two new C19-diterpenoid alkaloids, lasiandrine (1) and lasiandroline (2). Their structures were elucidated on the basis of extensive interpretation of spectroscopic and mass spectrometric data.


Assuntos
Aconitum/química , Alcaloides Diterpenos/química , Estrutura Molecular , Raízes de Plantas/química
14.
Angew Chem Int Ed Engl ; 55(50): 15667-15671, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27860043

RESUMO

A unified approach to four different (atisine, ajaconine, denudatine, and hetidine) diterpenoid alkaloid skeletons was developed and applied to the total synthesis of the natural products dihydroajaconine (2, atisine type) and gymnandine (4, denudatine type). The synthesis features a biogenetically inspired strategy that relies on C-H oxidation, aza-pinacol coupling, and aza-Prins cyclization as key steps.

15.
Sci Rep ; 6: 35353, 2016 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-27739459

RESUMO

Schistosoma japonicum is a widespread human and animal parasite that causes intestinal and hepatosplenic schistosomiasis linked to colon, liver and bladder cancers, and anemia. Estimated 230 million people are currently infected with Schistosoma spp, with 779 million people at risk of contracting the parasite. Infection occurs when a host comes into contact with cercariae, a planktonic larval stage of the parasite, and can be prevented by inactivating the larvae, commonly by chemical treatment. We investigated the use of physical non-equilibrium plasma generated at atmospheric pressure using custom-made dielectric barrier discharge reactor to kill S. japonicum cercariae. Survival rate decreased with treatment time and applied power. Plasmas generated in O2 and air gas discharges were more effective in killing S. japonicum cercariae than that generated in He, which is directly related to the mechanism by which cercariae are inactivated. Reactive oxygen species, such as O atoms, abundant in O2 plasma and NO in air plasma play a major role in killing of S. japonicum cercariae via oxidation mechanisms. Similar level of efficacy is also shown for a gliding arc discharge plasma jet generated in ambient air, a system that may be more appropriate for scale-up and integration into existing water treatment processes.


Assuntos
Cercárias/efeitos da radiação , Fígado/parasitologia , Schistosoma japonicum/efeitos da radiação , Esquistossomose Japônica/parasitologia , Animais , Humanos , Larva/patogenicidade , Larva/efeitos da radiação , Fígado/efeitos da radiação , Fenômenos Físicos , Schistosoma japonicum/patogenicidade , Esquistossomose Japônica/prevenção & controle
16.
Angew Chem Int Ed Engl ; 55(1): 392-6, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26545636

RESUMO

The first total syntheses of the architecturally complex atisane-type diterpenes and biogenetically related atisine-type diterpenoid alkaloids (±)-spiramilactone B, (±)-spiraminol, (±)-dihydroajaconine, and (±)-spiramines C and D are reported. Highlights of the synthesis include a late-stage biomimetic transformation of spiramilactone B, a facile formal lactone migration from the pentacyclic skeleton of spiramilactone E, a highly efficient and diastereoselective 1,7-enyne cycloisomerization to construct the functionalized tetracyclic atisane skeleton, and a tandem retro-Diels-Alder/intramolecular Diels-Alder sequence to achieve the tricyclo[6.2.2.0] ring system.


Assuntos
Alcaloides/síntese química , Diterpenos/síntese química , Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Alcaloides/química , Diterpenos/química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Conformação Molecular , Estereoisomerismo
17.
J Asian Nat Prod Res ; 18(4): 315-27, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26479584

RESUMO

Three new C20-diterpenoid alkaloids vilmorrianines E (1), F (2), and G (3) were isolated from the whole plants of Aconitum vilmorrianum, along with one artifact N-chloromethyl vilmorrianine E hydrochloride (4), as well as two known alkaloids hemsleyaconitines F (5) and G (6). The structures of 1-4 were established by HR-ESI-MS, 1D-, 2D-NMR (HMQC, HMBC, and NOESY), and single-crystal X-ray diffraction analysis. In addition, the structures of naturally occurring 2-O-acetylorochrine (7) and orochrine (8) were revised to be the known alkaloids heterophylloidine (9) and deacetyl heterophylloidine (10), respectively, on the basis of consideration of transannular effect and chemical correlations.


Assuntos
Aconitum/química , Alcaloides/isolamento & purificação , Diterpenos/isolamento & purificação , Alcaloides/química , Cristalografia por Raios X , Diterpenos/química , Estrutura Molecular , Raízes de Plantas/química
18.
J Asian Nat Prod Res ; 17(6): 638-48, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26235354

RESUMO

Overexpression of ATP-dependent efflux pump P-glycoprotein (P-gp) is the main cause of multidrug resistance (MDR) and chemotherapy failure in cancer treatment. Inhibition of P-gp-mediated drug efflux is an effective way to overcome cancer drug resistance. The present study investigated the reversal effect of the novel tetrandrine derivative W6 on P-gp-mediated MDR. KBv200, MCF-7/adr and their parental sensitive cell lines KB, MCF-7 were used for reversal study. The intracellular accumulation with P-gp substrates of doxorubicin was determined by flow cytometry. The expression of P-gp and ERK1/2 was investigated by western blot and real-time-PCR (RT-PCR) analysis. ATPase activity of P-gp was performed by P-gp-Glo(TM) assay systems. In comparison with P-gp-negative parental cells, W6 produced a favorable reversal effect in the MDR cells, as determined using the MTT assay. W6 significantly and dose-dependently increased intracellular accumulation of P-gp substrate doxorubicin (DOX) in P-gp overexpressing KBv200 cells, and also inhibited the ATPase activity of P-gp. W6 inhibited P-gp expression in KBv200 cells in a time-dependent manner, but it had no effect on MDR1 expression. In addition, W6 significantly decreased the ERK1/2 activation in KBv200 cells. Our results showed that W6 effectively reversed P-gp-mediated MDR by inhibiting the transport function and expression of P-gp, demonstrating the potential clinical utility of W6.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Benzilisoquinolinas/farmacologia , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Células KB , Estrutura Molecular
19.
Nat Prod Commun ; 10(6): 861-2, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26197500

RESUMO

Continuous investigations on the whole herbs of Aconitum tanguticum var. trichocarpum led to the isolation of three new C20-diterpenoid alkaloids trichocarpisines A-C (1-3). Their structures were elucidated on the basis of extensive interpretation of the spectroscopic data.


Assuntos
Aconitum/química , Alcaloides/química , Diterpenos/química , Extratos Vegetais/química , Alcaloides/isolamento & purificação , Diterpenos/isolamento & purificação , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray
20.
Nat Prod Commun ; 10(6): 1093-102, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26197559

RESUMO

Stemona alkaloids, featuring polycyclic structures and interesting bioactivities, constitute a distinct class from the Stemonaceae family. In this review, recent advances in the synthesis of these unique alkaloids are briefly discussed, highlighting the application of novel synthetic strategies to access the core structures, as well as creative solutions to the installation of multiple stereogenic centers. The literature reviewed in this article covers the publications from 2010 to November 2014, a period that witnessed the prosperity of the synthesis of Stemona alkaloids.


Assuntos
Alcaloides/síntese química , Medicamentos de Ervas Chinesas/síntese química , Stemonaceae/química , Alcaloides/química , Medicamentos de Ervas Chinesas/química , Estrutura Molecular
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