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1.
Int J Mol Sci ; 24(21)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37958986

RESUMO

Gastric cancer, particularly adenocarcinoma, is a significant global health concern. Environmental risk factors, such as Helicobacter pylori infection and diet, play a role in its development. This study aimed to characterize the chemical composition and evaluate the in vitro antibacterial and antitumor activities of an Aristolochia olivieri Colleg. ex Boiss. Leaves' methanolic extract (AOME). Additionally, morphological changes in gastric cancer cell lines were analyzed. AOME was analyzed using HPLC-MS/MS, and its antibacterial activity against H. pylori was assessed using the broth microdilution method. MIC and MBC values were determined, and positive and negative controls were included in the evaluation. Anticancer effects were assessed through in vitro experiments using AGS, KATO-III, and SNU-1 cancer cell lines. The morphological changes were examined through SEM and TEM analyses. AOME contained several compounds, including caffeic acid, rutin, and hyperoside. The extract displayed significant antimicrobial effects against H. pylori, with consistent MIC and MBC values of 3.70 ± 0.09 mg/mL. AOME reduced cell viability in all gastric cancer cells in a dose- and time-dependent manner. Morphological analyses revealed significant ultrastructural changes in all tumor cell lines, suggesting the occurrence of cellular apoptosis. This study demonstrated that AOME possesses antimicrobial activity against H. pylori and potent antineoplastic properties in gastric cancer cell lines. AOME holds promise as a natural resource for innovative nutraceutical approaches in gastric cancer management. Further research and in vivo studies are warranted to validate its potential clinical applications.


Assuntos
Aristolochia , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/prevenção & controle , Neoplasias Gástricas/metabolismo , Infecções por Helicobacter/metabolismo , Espectrometria de Massas em Tandem , Antibacterianos/química , Extratos Vegetais/química , Mucosa Gástrica/metabolismo
2.
Chem Res Toxicol ; 32(1): 100-112, 2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30560658

RESUMO

Stimulus-responsive cleavage reactions have found broad use to direct drug release at a particular target disease area. Increased levels of reactive oxygen species (ROS) have been associated with the development and progression of cancer and several other disease states, motivating the development of drug conjugates that can undergo a chemoselective ROS-triggered release. Melatonin (MLT) and the reactive electrophile p-benzoquinone methide ( p-QM) have evidenced either cytoprotective or cytotoxic effects in biological systems, depending on the dose, cellular targets, and time of exposure. In this study, we report the synthesis and biological activity of two MLT derivatives linked to ROS-responsive arylboronate triggers (P1 and P2), which can be activated by endogenously generated hydrogen peroxide (H2O2) to release MLT, or 5-methoxytryptamine (5-MeOT), and p-QM-intermediates. Their H2O2-induced activation mechanism was studied by HPLC-DAD-MS. P1, which rapidly releases MLT and p-QM, was able to strongly induce the Nrf2 antioxidant signaling pathway, but was ineffective to provide protection against H2O2-mediated oxidative damage. By contrast, P1 exhibited strong toxic effects in HeLa cancer cells, without causing significant toxicity to normal NCTC-2544 cells. Similar, although more limited, effects were exerted by P2. In both cases, cytotoxicity was accompanied by depletion of cellular glutathione (GSH), probably as a consequence of p-QM release, and increased ROS levels. A role for MLT in toxicity was also observed, suggesting that the P1 released products, MLT and p-QM, contributed additively to promote cell death.


Assuntos
Ácidos Borônicos/farmacologia , Desenho de Fármacos , Peróxido de Hidrogênio/farmacologia , Melatonina/farmacologia , Ácidos Borônicos/síntese química , Ácidos Borônicos/química , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células HeLa , Humanos , Peróxido de Hidrogênio/síntese química , Peróxido de Hidrogênio/química , Melatonina/síntese química , Melatonina/química , Estrutura Molecular , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
3.
J Org Chem ; 84(18): 12221-12227, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31476858

RESUMO

The concise and convergent total syntheses of (+)- and (-)-Fumimycin have been achieved by taking advantage of strategies for the asymmetric aza-Friedel-Crafts reaction of a highly substituted hydroquinone and N-fumaryl ketimine generated from the corresponding dehydroalanine. The enantiomerically pure natural product and its enantiomer were prepared in seven steps and 22% overall yield by employing both enantiomers of a BINOL-derived chiral phosphoric acid (CPA) catalyst.

4.
J Org Chem ; 84(12): 8027-8034, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31120249

RESUMO

The first total synthesis of natural (-)-clavicipitic acid from γ,γ-dimethylallyltryptophan (DMAT), its biosynthetic precursor, is described. This is done by regio- and chemoselective, remote, nondirected C(sp3)-H hydroxylation followed by aminocyclization. This study also features regio- and chemoselective Pd(0)-catalyzed linear prenylation at C4 of l-tryptophan boronic pinacol ester derivate, the latter obtained by a Lewis acid-promoted aziridine amino acid ring opening with 4-boronated indole. In addition, these results support the hypothesis that oxidative cyclization between amino acid nitrogen and the prenyl chain during clavicipitic acid biosynthesis can occur through the transient hydroxylated intermediate.


Assuntos
Carbono/química , Alcaloides de Claviceps/química , Alcaloides de Claviceps/síntese química , Hidrogênio/química , Triptofano/química , Catálise , Técnicas de Química Sintética , Ciclização , Hidroxilação
5.
J Org Chem ; 83(19): 12275-12283, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30191715

RESUMO

N-Acetyl ketimine generated from methyl 2-acetamidoacrylate was explored to develop an unprecedented domino aza-Friedel-Crafts/lactonization reaction with naphthols and phenols (including 5-hydroxyindoles). This novel method requires a catalyst loading of only 5 mol % of a phosphoric acid catalyst and provides a new series of 3-NHAc-naphtho- and benzofuranone derivatives bearing tetra-substituted stereogenic centers in moderate-to-good yields. The enantioselective variant using BINOL-derived phosphoric acids was also explored with 1-naphthol, providing the desired product with moderate enantioselectivities (up to 99:1 following recrystallization).

6.
Eur J Nutr ; 57(4): 1381-1395, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28283822

RESUMO

PURPOSE: CaCo-2 colon cancer cells and HepG2 liver cancer cells represent two malignant cell lines, which show a high resistance to apoptosis induced by the conventional anticancer drugs. Vitexin-2-O-xyloside (XVX) and avenanthramides (AVNs) are naturally occurring dietary agents from Beta vulgaris var. cicla L. and Avena sativa L., respectively. The aim of this work was to evaluate the antiproliferative effects and the reduction of the pro-survival mechanisms exerted by XVX and AVNs, used individually and in combination, in CaCo-2 and HepG2 cancer cells. METHODS: XVX and AVNs were isolated by liquid chromatography and characterized by HPLC-PDA-MS. The XVX and AVN antiproliferative effects were evaluated through sulforhodamine B method, while their pro-apoptotic effects through caspase activity assays. RTqPCR was used to investigate the modulation of the pro-survival factors baculoviral inhibitor of apoptosis repeat-containing 5 (BIRC5), hypoxia inducible factor 1 A (HIF1A), and vascular endothelial growth factor A (VEGFA). Cellular antioxidant activity (CAA) was investigated by means of DCFH-DA assay, whereas chemical antioxidant capacity was evaluated by the ORAC method. RESULTS: XVX and AVNs, both individually and in combination, inhibited the proliferation of CaCo-2 and HepG2 cancer cells, through activation of caspases 9, 8, and 3. XVX and AVNs downregulated the pro-survival genes BIRC5, HIF1A, and VEGFA. The CAA assay showed that AVNs exhibited strong antioxidant activity inside both CaCo-2 and HepG2 cells. CONCLUSIONS: The antiproliferative activity of the XVX + AVNs mixture represents an innovative treatment, which is effective against two types of cancer cells characterized by high resistance to the conventional anticancer drugs.


Assuntos
Apoptose , Flavonoides/farmacologia , Glicosídeos/farmacologia , ortoaminobenzoatos/farmacologia , Células CACO-2 , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Fator A de Crescimento do Endotélio Vascular
7.
J Org Chem ; 82(16): 8769-8775, 2017 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-28745505

RESUMO

We present the coupling of primary and secondary benzyl alcohols with indoles to form 3-benzylated indoles and H2O that is catalyzed, for the first time, by a complex of earth-abundant iron. This transformation accommodates a variety of substrates and is distinguished by its operational simplicity, sustainability, high functional-group tolerance, and amenability to gram-scale synthesis. On the basis of the preliminary experimental observations, we propose that the reaction proceeds through a borrowing hydrogen process.

8.
Biochim Biophys Acta ; 1852(9): 1960-70, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26096686

RESUMO

Parkinson's disease (PD) is the most common neurodegenerative movement disorder caused primarily by selective degeneration of the dopaminergic neurons in substantia nigra. In this work the proteomes extracted from primary fibroblasts of two unrelated, hereditary cases of PD patients, with different parkin mutations, were compared with the proteomes extracted from commercial adult normal human dermal fibroblasts (NHDF) and primary fibroblasts from the healthy mother of one of the two patients. The results show that the fibroblasts from the two different cases of parkin-mutant patients display analogous alterations in the expression level of proteins involved in different cellular functions, like cytoskeleton structure-dynamics, calcium homeostasis, oxidative stress response, protein and RNA processing.

9.
Biochim Biophys Acta ; 1842(7): 902-15, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24582596

RESUMO

Mitochondrial dysfunction and oxidative stress occur in Parkinson's disease (PD), but the molecular mechanisms controlling these events are not completely understood. Peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) is a transcriptional coactivator known as master regulator of mitochondrial functions and oxidative metabolism. Recent studies, including one from our group, have highlighted altered PGC-1α activity and transcriptional deregulation of its target genes in PD pathogenesis suggesting it as a new potential therapeutic target. Resveratrol, a natural polyphenolic compound proved to improve mitochondrial activity through the activation of several metabolic sensors resulting in PGC-1α activation. Here we have tested in vitro the effect of resveratrol treatment on primary fibroblast cultures from two patients with early-onset PD linked to different Park2 mutations. We show that resveratrol regulates energy homeostasis through activation of AMP-activated protein kinase (AMPK) and sirtuin 1 (SIRT1) and raise of mRNA expression of a number of PGC-1α's target genes resulting in enhanced mitochondrial oxidative function, likely related to a decrease of oxidative stress and to an increase of mitochondrial biogenesis. The functional impact of resveratrol treatment encompassed an increase of complex I and citrate synthase activities, basal oxygen consumption, and mitochondrial ATP production and a decrease in lactate content, thus supporting a switch from glycolytic to oxidative metabolism. Moreover, resveratrol treatment caused an enhanced macro-autophagic flux through activation of an LC3-independent pathway. Our results, obtained in early-onset PD fibroblasts, suggest that resveratrol may have potential clinical application in selected cases of PD-affected patients.


Assuntos
Mitocôndrias/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Estilbenos/farmacologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Trifosfato de Adenosina/genética , Trifosfato de Adenosina/metabolismo , Células Cultivadas , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Mitocôndrias/genética , Mitocôndrias/metabolismo , NAD/genética , NAD/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/genética , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Resveratrol , Sirtuína 1/genética , Sirtuína 1/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
10.
J Org Chem ; 80(6): 3217-22, 2015 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-25699684

RESUMO

The selective C3-alkylation of indoles with N-protected ethanolamines involving the "borrowing hydrogen" strategy is described. This method provides convenient and sustainable access to several tryptamine derivatives.


Assuntos
Alquilantes/química , Amino Álcoois/química , Indóis/química , Irídio/química , Compostos Organometálicos/química , Triptaminas/síntese química , Catálise , Estrutura Molecular , Triptaminas/química
11.
J Org Chem ; 79(7): 3255-9, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-24605802

RESUMO

A new and short synthesis of racemic cis-clavicipitic acid was achieved by taking advantage of the double nucleophilic character of indole-4-pinacolboronic ester. Key to the success of the synthesis were an efficient and selective C-3 indole Friedel-Crafts alkylation and the development of an unprecedented intramolecular rhodium-catalyzed 1,2-addition of an aryl pinacolboronic ester to an unactivated imine.


Assuntos
Ácidos Borônicos/química , Ácidos Borônicos/síntese química , Alcaloides de Claviceps/síntese química , Iminas/química , Indóis/química , Indóis/síntese química , Ródio/química , Alquilação , Catálise , Ésteres , Estrutura Molecular , Estereoisomerismo
12.
Beilstein J Org Chem ; 10: 1991-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25246958

RESUMO

The reaction of 3-substituted indoles with dehydroalanine (Dha) derivatives under Lewis acid-mediated conditions has been investigated. The formation of 2-substituted tryptophans is proposed to occur through a selective alkylative dearomatization-cyclization followed by C3- to C2-alkyl migration and rearomatization.

13.
ChemMedChem ; : e202400134, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778632

RESUMO

The establishment of the Young Scientists Network (YSN) by the European Federation for Medicinal Chemistry (EFMC) served as a proactive response to the evolving landscape of the scientific community. The YSN aims to assist early-career medicinal chemists and chemical biologists by responding to emerging themes, such as the influence of social media, shifts in gender balance within the scientific population, and evolving educational opportunities. The YSN also ensures that the upcoming generation of scientists actively contributes to shape the EFMC's strategic direction while addressing their specific needs. Initially conceived as a general concept, YSN has evolved into a proactive and dynamic team which demonstrates a tangible impact. To boost the impact of the YSN and involve additional motivated young scientists, we have adopted a novel organization, and structured the team in seven working groups (WGs). Herein, we will discuss the tasks of the different WGs as well as the activities planned for the near future. We believe this structure will strengthen the pivotal role YSN has already played in serving medicinal chemists and chemical biologists in Europe. The YSN now has the structure and motivation to pave the way to attract young scientists across Europe and to give them the stage within EFMC.

14.
J Org Chem ; 78(15): 7727-34, 2013 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-23845025

RESUMO

The synthetic efforts toward the concise synthesis of (-)-indolactam V from simple and commercially available starting materials using palladium- and copper-catalyzed intramolecular N-arylation strategy for the elaboration of the requisite nine-membered lactam ring as the key step are described. The incorporation of a turn-inducing structural element along the linear precursor was fundamental to achieve the heterocyclization step as well as obtain the correct regio- and chemoselectivity. The stereoselective nature in the C-N coupling cyclization reaction is interpreted in terms of minimization of allylic strain at the transition state for the palladium-amido complex formation. Meanwhile, the synthesis of the (-)-epi-indolactam V and its enantiomer have been accomplished.


Assuntos
Indóis/síntese química , Lactamas/síntese química , Ciclização , Indóis/química , Lactamas/química , Estrutura Molecular , Estereoisomerismo
15.
Biomed Pharmacother ; 158: 114083, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36495668

RESUMO

COronaVIrus Disease 2019 (COVID-19) is a newly emerging infectious disease that spread across the world, caused by the novel coronavirus Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2). Despite the advancements in science that led to the creation of the vaccine, there is still an urgent need for new antiviral drugs effective against SARS-CoV-2. This study aimed to investigate the antiviral effect of Paulownia tomentosa Steud extract against SARS-CoV-2 and to evaluate its antioxidant properties, including respiratory smooth muscle relaxant effects. Our results showed that P. tomentosa extract can inhibit viral replication by directly interacting with both the 3-chymotrypsin-like protease and spike protein. In addition, the phyto complex does not reduce lung epithelial cell viability and exerts a protective action in those cells damaged by tert-butyl hydroperoxide , a toxic agent able to alter cells' functions via increased oxidative stress. These data suggest the potential role of P. tomentosa extract in COVID-19 treatment, since this extract is able to act both as an antiviral and a cytoprotective agent in vitro.


Assuntos
COVID-19 , Humanos , Antivirais/uso terapêutico , SARS-CoV-2 , Antioxidantes/farmacologia , Tratamento Farmacológico da COVID-19 , Extratos Vegetais/farmacologia , Músculo Liso
17.
Eur J Med Chem ; 243: 114762, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36150258

RESUMO

In crystal structures of melatonin MT1 and MT2 receptors, a lipophilic subpocket has been characterized which accommodates the phenyl ring of the potent agonist 2-phenylmelatonin. This subpocket appears a key structural element to achieve high binding affinity and selectivity for the MT2 receptor. A series of 2-arylindole ligands was synthesized to probe the requirements for the optimal occupation and interaction with the 2-phenyl binding pocket. Thermodynamic integration simulations applied to MT1 and MT2 receptors in complex with the α-naphthyl derivative provided a rationale for the MT2-selectivity and investigation on the binding mode of a couple of atropisomers allowed to define the available space and arrangement of substituents inside the subpocket. Interestingly, more hydrophilic 2-aza-substituted compounds displayed high binding affinity and molecular dynamics simulations highlighted polar interaction with residues from the subpocket that could be responsible for their potency.


Assuntos
Melatonina , Receptor MT1 de Melatonina , Receptor MT2 de Melatonina , Ligantes , Melatonina/análogos & derivados , Melatonina/química , Melatonina/metabolismo , Simulação de Dinâmica Molecular , Receptor MT1 de Melatonina/química , Receptor MT1 de Melatonina/metabolismo , Receptor MT2 de Melatonina/química , Receptor MT2 de Melatonina/metabolismo
18.
Mov Disord ; 26(14): 2563-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21956541

RESUMO

BACKGROUND: The objective of this study was to evaluate the possible association between endogenous and exogenous estrogens and Parkinson's disease (PD). METHODS: The FRAGAMP study is a large Italian multicenter case-control study. PD was diagnosed according to Gelb's criteria. A standardized questionnaire was administered to record demographic, epidemiological, and clinical data. Adjusted ORs and 95% CIs were estimated using multivariate analysis (logistic regression). RESULTS: Two hundred PD women (mean age, 68.0 ± 9.5 years) and 299 control women (mean age, 61.8 ± 9.9 years) were enrolled in the study. Age at menarche, age at menopause, fertile life duration, cumulative duration of pregnancies, hormone replacement therapy, and surgical menopause were not significantly associated with PD. Multivariate analysis showed a significant positive association between use of oral contraceptives and PD, with an adjusted OR of 3.27 (95% CI, 1.24-8.59; P = .01). CONCLUSIONS: Our data suggest that oral contraceptives could increase the risk of PD.


Assuntos
Anticoncepcionais Orais Hormonais/uso terapêutico , Terapia de Reposição de Estrogênios/estatística & dados numéricos , Estrogênios/uso terapêutico , Leiomioma/epidemiologia , Menopausa/fisiologia , Doença de Parkinson/epidemiologia , Neoplasias Uterinas/epidemiologia , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Itália/epidemiologia , Modelos Logísticos , Pessoa de Meia-Idade , Análise Multivariada , Gravidez , Reprodução/fisiologia , Fatores de Risco , Inquéritos e Questionários
19.
Antioxidants (Basel) ; 10(2)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33530504

RESUMO

I-152 combines two pro-glutathione (GSH) molecules, namely N-acetyl-cysteine (NAC) and cysteamine (MEA), to improve their potency. The co-drug efficiently increases/replenishes GSH levels in vitro and in vivo; little is known about its mechanism of action. Here we demonstrate that I-152 not only supplies GSH precursors, but also activates the antioxidant kelch-like ECH-associated protein 1/nuclear factor E2-related factor 2 (KEAP1/NRF2) pathway. The mechanism involves disulfide bond formation between KEAP1 cysteine residues, NRF2 stabilization and enhanced expression of the γ-glutamil cysteine ligase regulatory subunit. Accordingly, a significant increase in GSH levels, not reproduced by treatment with NAC or MEA alone, was found. Compared to its parent compounds, I-152 delivered NAC more efficiently within cells and displayed increased reactivity to KEAP1 compared to MEA. While at all the concentrations tested, I-152 activated the NRF2 pathway; high doses caused co-activation of activating transcription factor 4 (ATF4) and ATF4-dependent gene expression through a mechanism involving Atf4 transcriptional activation rather than preferential mRNA translation. In this case, GSH levels tended to decrease over time, and a reduction in cell proliferation/survival was observed, highlighting that there is a concentration threshold which determines the transition from advantageous to adverse effects. This body of evidence provides a molecular framework for the pro-GSH activity and dose-dependent effects of I-152 and shows how synergism and cross reactivity between different thiol species could be exploited to develop more potent drugs.

20.
Antioxidants (Basel) ; 10(3)2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33801467

RESUMO

Prunus spinosa L. fruit (PSF) ethanol extract, showing a peculiar content of biologically active molecules (polyphenols), was investigated for its wound healing capacity, a typical feature that declines during aging and is negatively affected by the persistence of inflammation and oxidative stress. To this aim, first, PSF anti-inflammatory properties were tested on young and senescent LPS-treated human umbilical vein endothelial cells (HUVECs). As a result, PSF treatment increased miR-146a and decreased IRAK-1 and IL-6 expression levels. In addition, the PSF antioxidant effect was validated in vitro with DPPH assay and confirmed by in vivo treatments in C. elegans. Our findings showed beneficial effects on worms' lifespan and healthspan with positive outcomes on longevity markers (i.e., miR-124 upregulation and miR-39 downregulation) as well. The PSF effect on wound healing was tested using the same cells and experimental conditions employed to investigate PSF antioxidant and anti-inflammaging ability. PSF treatment resulted in a significant improvement of wound healing closure (ca. 70%), through cell migration, both in young and older cells, associated to a downregulation of inflammation markers. In conclusion, PSF extract antioxidant and anti-inflammaging abilities result in improved wound healing capacity, thus suggesting that PSF might be helpful to improve the quality of life for its beneficial health effects.

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