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1.
Chembiochem ; 25(1): e202300730, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37877519

RESUMO

Engineering bioactive iminosugars with pH-responsive groups is an emerging approach to develop pharmacological chaperones (PCs) able to improve lysosomal trafficking and enzymatic activity rescue of mutated enzymes. The use of inexpensive l-malic acid allowed introduction of orthoester units into the lipophilic chain of an enantiomerically pure iminosugar affording only two diastereoisomers contrary to previous related studies. The iminosugar was prepared stereoselectively from the chiral pool (d-mannose) and chosen as the lead bioactive compound, to develop novel candidates for restoring the lysosomal enzyme glucocerebrosidase (GCase) activity. The stability of orthoester-appended iminosugars was studied by 1 H NMR spectroscopy both in neutral and acidic environments, and the loss of inhibitory activity with time in acid medium was demonstrated on cell lysates. Moreover, the ability to rescue GCase activity in the lysosomes as the result of a chaperoning effect was explored. A remarkable pharmacological chaperone activity was measured in fibroblasts hosting the homozygous L444P/L444P mutation, a cell line resistant to most PCs, besides the more commonly responding N370S mutation.


Assuntos
Doença de Gaucher , Glucosilceramidase , Humanos , Doença de Gaucher/tratamento farmacológico , Doença de Gaucher/genética , Piperidinas/farmacologia , Piperidinas/metabolismo , Mutação , Fibroblastos , Concentração de Íons de Hidrogênio
2.
Org Biomol Chem ; 21(47): 9362-9371, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-37975191

RESUMO

N-Acetylgalactosamine-6-sulfatase (GALNS) is an enzyme whose deficiency is related to the lysosomal storage disease Morquio A. For the development of effective therapeutic approaches against this disease, the design of suitable enzyme enhancers (i.e. pharmacological chaperones) is fundamental. The natural substrates of GALNS are the glycosaminoglycans keratan sulfate and chondroitin 6-sulfate, which mainly display repeating units of sulfated carbohydrates. With a biomimetic approach, gold nanoparticles (AuNPs) decorated with simple monosaccharides, sulfated ligands (homoligand AuNPs), or both monosaccharides and sulfated ligands (mixed-ligand AuNPs) were designed here as multivalent inhibitors of GALNS. Among the homoligand AuNPs, the most effective inhibitors of GALNS activity are the ß-D-galactoside-coated AuNPs. In the case of mixed-ligand AuNPs, ß-D-galactosides/sulfated ligands do not show better inhibition than the ß-D-galactoside-coated AuNPs. However, a synergistic effect is observed for α-D-mannosides in a mixed-ligand coating with sulfated ligands that reduced IC50 by one order of magnitude with respect to the homoligand α-D-mannoside-coated AuNPs. SAXS experiments corroborated the association of GALNS with ß-D-galactoside AuNPs. These AuNPs are able to restore the enzyme activity by almost 2-fold after thermal denaturation, indicating a potential chaperoning activity towards GALNS. This information could be exploited for future development of nanomedicines for Morquio A. The recent implications of GALNS in cancer and neuropathic pain make these kinds of multivalent bionanomaterials of great interest towards multiple therapies.


Assuntos
Condroitina Sulfatases , Nanopartículas Metálicas , Ouro , Acetilgalactosamina , Monossacarídeos , Ligantes , Sulfatos , Espalhamento a Baixo Ângulo , Difração de Raios X , Lisossomos
3.
Front Oncol ; 13: 1245248, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37901327

RESUMO

In the early stages of carcinogenesis, the transformed cells become "invisible" to the immune system. From this moment on, the evolution of the tumor depends essentially on the genotype of the primitive cancer cells and their subsequent genetic drift. The role of the immune system in blocking tumor progression from the earliest stages is largely underestimated because by the time tumors are clinically detectable, the immune system has already completely failed its task. Therefore, a clinical treatment capable of restoring the natural anti-tumor role of the immune system could prove to be the "ultimate weapon" against cancer. Herein, we propose a novel therapeutic approach for the treatment of solid cancer that exploits the capability of activated monocytes to transfer major histocompatibility complex I (MHC-I) molecules bound to antigenic peptides to cancer cells using microvesicles as cargo, making tumor cells target of a "natural" CD8+ T lymphocyte cytotoxic response.

4.
Biology (Basel) ; 12(9)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37759562

RESUMO

Animal feeding through the reuse of agro-industrial by-products in one of the ultimate goals of sustainable agriculture. Olive oil pomace (OOP) produced as a waste product during olive oil milling has been used as an ingredient in the diet for Holstein lactating cows. Recent findings have shown no decrease in animal performance, feed intake or detrimental effect on rumen microbiota. In contrast, an improvement in C18 polyunsaturated fatty acids has been observed. In this work, the milk protein content from cows fed a commercial diet (CON) or an experimental one supplemented with OOP was determined and compared, and the peptides derived from the simulated gastrointestinal digestion of raw milk were analyzed. After fractionation via RP-HPLC, peptides were characterized for their biological activity on different cell lines. The ability to reduce both the intracellular ROS content and the expression of inflammatory markers, such as Cyclooxygenase, isoenzyme 2 (COX-2) and inducible Nitric Oxide Synthase (iNOS), as well as the remarkable properties to induce cell differentiation and to slow down the proliferation of human intestinal cancer cells, enable us to define them as bioactive peptides. In spite of there being no observed significant difference between the healthy activity of CON and OOP peptides, the results allow us to broaden the knowledge about the biological activity of these bioactive peptides and to confirm that agro-industrial by-products may be successfully incorporated into the feeding strategy of dairy cows.

5.
Eur J Med Chem ; 252: 115270, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36934484

RESUMO

Type 2 diabetes mellitus (T2DM) is a serious chronic disease with an alarmingly growing worldwide prevalence. Current treatment of T2DM mainly relies on drug combinations in order to control blood glucose levels and consequently prevent the onset of hyperglycaemia-related complications. The development of multiple-targeted drugs recently emerged as an attractive alternative to drug combinations for the treatment of complex diseases with multifactorial pathogenesis, such as T2DM. Protein tyrosine phosphatase 1B (PTP1B) and aldose reductase (AKR1B1) are two enzymes crucially involved in the development of T2DM and its chronic complications and, therefore, dual inhibitors targeted to both these enzymes could provide novel agents for the treatment of this complex pathological condition. In continuing our search for dual-targeted PTP1B/AKR1B1 inhibitors, we designed new (5-arylidene-4-oxo-2-thioxothiazolidin-3-yl)alkanoic acids. Among them, 3-(4-phenylbutoxy)benzylidene derivatives 6f and 7f, endowed with interesting inhibitory activity against both targets, proved to control specific cellular pathways implicated in the development of T2DM and related complications.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Monoéster Fosfórico Hidrolases , Ligantes , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Aldeído Redutase
6.
Acta Oncol ; 62(1): 15-24, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36786345

RESUMO

INTRODUCTION: To ensure that all citizens have equal access to high-quality cancer diagnosis and care, the EU4Health Programme, Europe's Beating Cancer Plan, and Horizon Europe's Cancer Mission propose Comprehensive Cancer Infrastructures in every European Union Member State. It is therefore important to establish the basic principles for high-performing cancer networks and a methodology for evaluating their quality and effectiveness. This article describes methods and standards/indicators for network evaluation found in literature, gives a comparative overview of the new OECI European Cancer Network Quality standards, and proposes principles for evaluating the performance of Comprehensive Cancer Networks as a basis for continuous improvement. MATERIALS AND METHODS: We performed a scoping literature review on methods and standards/indicators for care-network evaluation. We then compared the OECI set with literature findings, categorised standards that were similar, reflected on standards that were different, and deduced principles for quality standards for cancer networks. RESULTS: Of 1002 articles identified, 17 reported on evaluation methods and/or (mostly) qualitative indicators. Sixteen studies described indicators/standards for evaluating care networks, critical success factors or desirable outcomes. Of the 54 present OECI standards, 32 had a literature equivalent. No literature equivalent was found for 22 standards, especially on those related to the combination of care and research. The proposed OECI evaluation methods (survey, document review, and interviews) were all reported in the literature. From the conformity of these results, we deduced 8 principles for standards evaluating the effectiveness of Comprehensive Cancer Networks. CONCLUSIONS: Research on the evaluation of the effectiveness of care networks is scarce. Evaluation methods vary and are often single time-point assessments. The OECI set contributes to establishing clear principles and standards to evaluate the effectiveness of Comprehensive Cancer Networks.


Assuntos
Neoplasias , Humanos , Neoplasias/diagnóstico , Neoplasias/terapia , União Europeia
7.
J Med Chem ; 66(5): 3566-3587, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36790935

RESUMO

A new series of analogues or derivatives of the previously reported PPARα/γ dual agonist LT175 allowed the identification of ligand 10, which was able to potently activate both PPARα and -γ subtypes as full and partial agonists, respectively. Docking studies were performed to provide a molecular explanation for this different behavior on the two different targets. In vivo experiments showed that this compound induced a significant reduction in blood glucose and lipid levels in an STZ-induced diabetic mouse model displaying no toxic effects on bone, kidney, and liver. By examining in depth the antihyperglycemic activity of 10, we found out that it produced a slight but significant inhibition of the mitochondrial pyruvate carrier, acting also through insulin-independent mechanisms. This is the first example of a PPARα/γ dual agonist reported to show this inhibitory effect representing, therefore, the potential lead of a new class of drugs for treatment of dyslipidemic type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , PPAR alfa , Camundongos , Animais , PPAR alfa/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Transportadores de Ácidos Monocarboxílicos , Agonistas PPAR-gama , PPAR gama/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico
8.
Pharmaceutics ; 15(2)2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36839851

RESUMO

Type 2 diabetes mellitus (T2DM) is a complex disease characterized by impaired glucose homeostasis and serious long-term complications. First-line therapeutic options for T2DM treatment are monodrug therapies, often replaced by multidrug therapies to ensure that non-responding patients maintain target glycemia levels. The use of multitarget drugs instead of mono- or multidrug therapies has been emerging as a main strategy to treat multifactorial diseases, including T2DM. Therefore, modern drug discovery in its early stages aims to identify potential modulators for multiple targets; for this purpose, exploration of the chemical space of natural products represents a powerful tool. Our study demonstrates that avarone, a sesquiterpene quinone obtained from the sponge Dysidea avara, is capable of inhibiting in vitro PTP1B, the main negative regulator of the insulin receptor, while it improves insulin sensitivity, and mitochondria activity in C2C12 cells. We observe that when avarone is administered alone, it acts as an insulin-mimetic agent. In addition, we show that avarone acts as a tight binding inhibitor of aldose reductase (AKR1B1), the enzyme involved in the development of diabetic complications. Overall, avarone could be proposed as a novel natural hit to be developed as a multitarget drug for diabetes and its pathological complications.

9.
Chemistry ; 29(19): e202203841, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36598148

RESUMO

Piperidine-based photoswitchable derivatives have been developed as putative pharmacological chaperones for glucocerebrosidase (GCase), the defective enzyme in Gaucher disease (GD). The structure-activity study revealed that both the iminosugar and the light-sensitive azobenzene are essential features to exert inhibitory activity towards human GCase and a system with the correct inhibition trend (IC50 of the light-activated form lower than IC50 of the dark form) was identified. Kinetic analyses showed that all compounds are non-competitive inhibitors (mixed or pure) of GCase and the enzyme allosteric site involved in the interaction was identified by means of MD simulations. A moderate activity enhancement of mutant GCase assessed in GD patients' fibroblasts (ex vivo experiments) carrying the most common mutation was recorded. This promising observation paves the way for further studies to improve the benefit of the light-to-dark thermal conversion for chaperoning activity.


Assuntos
Doença de Gaucher , Glucosilceramidase , Humanos , Glucosilceramidase/genética , Glucosilceramidase/metabolismo , Doença de Gaucher/tratamento farmacológico , Doença de Gaucher/genética , Dobramento de Proteína , Fibroblastos/metabolismo , Mutação , Inibidores Enzimáticos/farmacologia
10.
FASEB J ; 36(12): e22655, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36421008

RESUMO

Trodusquemine is an aminosterol with a variety of biological and pharmacological functions, such as acting as an antimicrobial, stimulating body weight loss and interfering with the toxicity of proteins involved in the development of Alzheimer's and Parkinson's diseases. The mechanisms of interaction of aminosterols with cells are, however, still largely uncharacterized. Here, by using fluorescently labeled trodusquemine (TRO-A594 and TRO-ATTO565), we show that trodusquemine binds initially to the plasma membrane of living cells, that the binding affinity is dependent on cholesterol, and that trodusquemine is then internalized and mainly targeted to lysosomes after internalization. We also found that TRO-A594 is able to strongly and selectively bind to myelinated fibers in fixed mouse brain slices, and that it is a marker compatible with tissue clearing and light-sheet fluorescence microscopy or expansion microscopy. In conclusion, this work contributes to further characterize the biology of aminosterols and provides a new tool for nerve labeling suitable for the most advanced microscopy techniques.


Assuntos
Colestanos , Animais , Camundongos , Colestanos/farmacologia , Espermina/farmacologia , Microscopia de Fluorescência/métodos , Colesterol
11.
Cancer Manag Res ; 14: 3105-3118, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36340999

RESUMO

A multidisciplinary panel of experts and cancer patients developed a position paper to highlight recent evidence on "cancer cure" (ie, the possibility of achieving the same life expectancy as the general population) and discuss the consequences of this concept on follow-up and rehabilitation strategies. The aim is to inform clinicians, patients, and health-care policy makers about strategies of survivorship care for cured cancer patients and consequences impacting patient lives, spurring public health authorities and research organizations to implement resources to the purpose. Two identifiable, measurable, and reproducible indicators of cancer cure are presented. Cure fraction (CF) is >60% for breast and prostate cancer patients, >50% for colorectal cancer patients, and >70% for patients with melanoma, Hodgkin lymphoma, and cancers of corpus uteri, testis (>90%), and thyroid. CF was >65% for patients diagnosed at ages 15-44 years and 30% for those aged 65-74 years. Time-to-cure was consistently <1 year for thyroid and testicular cancer patients and <10 years for patients with colorectal and cervical cancers, melanoma, and Hodgkin lymphoma. The working group agrees that the evidence allows risk stratification of cancer patients and implementation of personalized care models for timely diagnosis, as well as treatment of possible cancer relapses or related long-term complications, and preventive measures aimed at maintaining health status of cured patients. These aspects should be integrated to produce an appropriate follow-up program and survivorship care plan(s), avoiding stigma and supporting return to work, to a reproductive life, and full rehabilitation. The "right to be forgotten" law, adopted to date only in a few European countries, may contribute to these efforts for cured patients.

12.
Cell Rep ; 40(7): 111233, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35977477

RESUMO

5-Fluorouracil (5-FU) is a key component of chemotherapy for colorectal cancer (CRC). 5-FU efficacy is established by intracellular levels of folate cofactors and DNA damage repair strategies. However, drug resistance still represents a major challenge. Here, we report that alterations in serine metabolism affect 5-FU sensitivity in in vitro and in vivo CRC models. In particular, 5-FU-resistant CRC cells display a strong serine dependency achieved either by upregulating endogenous serine synthesis or increasing exogenous serine uptake. Importantly, regardless of the serine feeder strategy, serine hydroxymethyltransferase-2 (SHMT2)-driven compartmentalization of one-carbon metabolism inside the mitochondria represents a specific adaptation of resistant cells to support purine biosynthesis and potentiate DNA damage response. Interfering with serine availability or affecting its mitochondrial metabolism revert 5-FU resistance. These data disclose a relevant mechanism of mitochondrial serine use supporting 5-FU resistance in CRC and provide perspectives for therapeutic approaches.


Assuntos
Neoplasias Colorretais , Neoplasias , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Resistencia a Medicamentos Antineoplásicos/genética , Fluoruracila/metabolismo , Fluoruracila/farmacologia , Humanos , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Nucleotídeos/metabolismo , Serina/metabolismo
13.
Molecules ; 27(13)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35807262

RESUMO

GM1 gangliosidosis is a rare lysosomal disease caused by the deficiency of the enzyme ß-galactosidase (ß-Gal; GLB1; E.C. 3.2.1.23), responsible for the hydrolysis of terminal ß-galactosyl residues from GM1 ganglioside, glycoproteins, and glycosaminoglycans, such as keratan-sulfate. With the aim of identifying new pharmacological chaperones for GM1 gangliosidosis, the synthesis of five new trihydroxypiperidine iminosugars is reported in this work. The target compounds feature a pentyl alkyl chain in different positions of the piperidine ring and different absolute configurations of the alkyl chain at C-2 and the hydroxy group at C-3. The organometallic addition of a Grignard reagent onto a carbohydrate-derived nitrone in the presence or absence of a suitable Lewis Acid was exploited, providing structural diversity at C-2, followed by the ring-closure reductive amination step. An oxidation-reduction process allowed access to a different configuration at C-3. The N-pentyl trihydroxypiperidine iminosugar was also synthesized for the purpose of comparison. The biological evaluation of the newly synthesized compounds was performed on leucocyte extracts from healthy donors and identified two suitable ß-Gal inhibitors, namely compounds 10 and 12. Among these, compound 12 showed chaperoning properties since it enhanced ß-Gal activity by 40% when tested on GM1 patients bearing the p.Ile51Asn/p.Arg201His mutations.


Assuntos
Gangliosidose GM1 , Gangliosidose GM1/tratamento farmacológico , Gangliosidose GM1/genética , Humanos , Lisossomos , Chaperonas Moleculares/genética , Mutação , beta-Galactosidase/química
14.
Eur J Med Chem ; 235: 114240, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35325635

RESUMO

The peroxisome proliferator-activated receptors (PPARs) are nuclear receptors involved in the regulation of the metabolic homeostasis and therefore represent valuable therapeutic targets for the treatment of metabolic diseases. The development of more balanced drugs interacting with PPARs, devoid of the side-effects showed by the currently marketed PPARγ full agonists, is considered the major challenge for the pharmaceutical companies. Here we present a chemoinformatics search approach for new ligands that let us identify a novel PPAR pan-agonist with a very attractive activity profile being able to reduce lipid accumulation and improve insulin sensitivity. This compound represents, therefore, the potential lead of a new class of drugs for treatment of dyslipidemic type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Quimioinformática , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Ligantes , Lipídeos , PPAR gama/agonistas , Receptores Ativados por Proliferador de Peroxissomo/metabolismo
15.
Chembiochem ; 23(11): e202200077, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35322924

RESUMO

The synthesis of five new multivalent derivatives of a trihydroxypiperidine iminosugar was accomplished through copper catalyzed alkyne-azide cycloaddition (CuAAC) reaction of an azido ending piperidine and several propargylated scaffolds. The resulting multivalent architectures were assayed as inhibitors of lysosomal GCase, the defective enzyme in Gaucher disease. The multivalent compounds resulted in much more potent inhibitors than a parent monovalent reference compound, thus showing a good multivalent effect. Biological investigation of these compounds as pharmacological chaperones revealed that the trivalent derivative (12) gives a 2-fold recovery of the GCase activity on Gaucher patient fibroblasts bearing the L444P/L444P mutations responsible for neuropathies. Additionally, a thermal denaturation experiment showed its ability to impart stability to the recombinant enzyme used in therapy.


Assuntos
Doença de Gaucher , Glucosilceramidase , Inibidores Enzimáticos/farmacologia , Fibroblastos , Doença de Gaucher/tratamento farmacológico , Doença de Gaucher/genética , Glucosilceramidase/genética , Glucosilceramidase/uso terapêutico , Humanos , Mutação
16.
Pharmaceuticals (Basel) ; 15(3)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35337123

RESUMO

Diabetes mellitus (DM) represents a complex and multifactorial disease that causes metabolic disorders with acute and long-term serious complications. The onset of DM, with over 90% of cases of diabetes classified as type 2, implies several metabolic dysfunctions leading to consider DM a worldwide health problem. In this frame, protein tyrosine phosphatase 1B (PTP1B) and aldose reductase (AR) are two emerging targets involved in the development of type 2 diabetes mellitus (T2DM) and its chronic complications. Herein, we employed a marine-derived dual type inhibitor of these enzymes, phosphoeleganin, as chemical starting point to perform a fragment-based process in search for new inhibitors. Phosphoeleganin was both disassembled by its oxidative cleavage and used as model structure for the synthesis of a small library of functionalized derivatives as rationally designed analogues. Pharmacological screening supported by in silico docking analysis outlined the mechanism of action against PTP1B exerted by a phosphorylated fragment and a synthetic simplified analogue, which represent the most potent inhibitors in the library.

17.
Org Biomol Chem ; 20(8): 1637-1641, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35107482

RESUMO

Light-switchable inhibitors of the enzyme ß-glucocerebrosidase (GCase) have been developed by anchoring a specific azasugar to a dihydroazulene or an azobenzene responsive moiety. Their inhibitory effect towards human GCase, before and after irradiation are reported, and the effect on thermal denaturation of recombinant GCase and cytotoxicity were studied on selected candidates.


Assuntos
Compostos Azo/farmacologia , Azulenos/farmacologia , Inibidores Enzimáticos/farmacologia , Glucosilceramidase/antagonistas & inibidores , Compostos Azo/síntese química , Compostos Azo/química , Azulenos/síntese química , Azulenos/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Glucosilceramidase/metabolismo , Humanos , Luz , Estrutura Molecular , Processos Fotoquímicos
18.
Mar Drugs ; 20(1)2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35049920

RESUMO

The chemical investigation of the Mediterranean ascidian Clavelina lepadiformis has led to the isolation of a new lepadin, named lepadin L, and two known metabolites belonging to the same family, lepadins A and B. The planar structure and relative configuration of the decahydroquinoline ring of lepadin L were established both by means of HR-ESIMS and by a detailed as extensive analysis of 1D and 2D NMR spectra. Moreover, microscale derivatization of the new alkaloid lepadin L was performed to assess the relative configuration of the functionalized alkyl side chain. Lepadins A, B, and L were tested for their cytotoxic activity on a panel of cancer cell lines (human melanoma [A375], human breast [MDA-MB-468], human colon adenocarcinoma [HT29], human colorectal carcinoma [HCT116], and mouse myoblast [C2C12]). Interestingly, a deeper investigation into the mechanism of action of the most cytotoxic metabolite, lepadin A, on the A375 cells has highlighted its ability to induce a strongly inhibition of cell migration, G2/M phase cell cycle arrest and a dose-dependent decrease of cell clonogenity, suggesting that it is able to impair self-renewing capacity of A375 cells.


Assuntos
Alcaloides/farmacologia , Antineoplásicos/farmacologia , Urocordados , Alcaloides/química , Animais , Antineoplásicos/química , Organismos Aquáticos , Linhagem Celular Tumoral/efeitos dos fármacos , Humanos , Mar Mediterrâneo , Camundongos , Relação Estrutura-Atividade
19.
Eur J Nutr ; 61(4): 1905-1918, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35066640

RESUMO

PURPOSE: The impact of tea constituents on the insulin-signaling pathway as well as their antidiabetic activity are still debated questions. Previous studies suggested that some tea components act as Protein Tyrosine Phosphatase 1B (PTP1B) inhibitors. However, their nature and mechanism of action remain to be clarified. This study aims to evaluate the effects of both tea extracts and some of their constituents on two main negative regulators of the insulin-signaling pathway, Low-Molecular-Weight Protein Tyrosine Phosphatase (LMW-PTP) and PTP1B. METHODS: The effects of cold and hot tea extracts on the enzyme activity were evaluated through in vitro assays. Active components were identified using gas chromatography-mass spectrometry (GC-MS) analysis. Finally, the impact of both whole tea extracts and specific active tea components on the insulin-signaling pathway was evaluated in liver and muscle cells. RESULTS: We found that both cold and hot tea extracts inhibit LMW-PTP and PTP1B, even if with a different mechanism of action. We identified galloyl moiety-bearing catechins as the tea components responsible for this inhibition. Specifically, kinetic and docking analyses revealed that epigallocatechin gallate (EGCG) is a mixed-type non-competitive inhibitor of PTP1B, showing an IC50 value in the nanomolar range. Finally, in vitro assays confirmed that EGCG acts as an insulin-sensitizing agent and that the chronic treatment of liver cells with tea extracts results in an enhancement of the insulin receptor levels and insulin sensitivity. CONCLUSION: Altogether, our data suggest that tea components are able to regulate both protein levels and activation status of the insulin receptor by modulating the activity of PTP1B.


Assuntos
Resistência à Insulina , Proteínas Tirosina Fosfatases , Receptor de Insulina , Chá , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos , Insulina/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Receptor de Insulina/metabolismo , Transdução de Sinais , Chá/química
20.
Tumori ; 108(3): 213-222, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33876985

RESUMO

OBJECTIVE: To describe smoking behaviours of patients with incident cancer attending an Italian cancer centre and to examine changes in their smoking habits within 12 months from cancer diagnosis, evaluating determinants of smoking cessation. METHODS: A hospital-based prospective cohort included patients hospitalized in an Italian cancer centre (2016-2018). Patients were mostly female (74%) and included a limited proportion of aerodigestive cancers (7%). Face-to-face interviews were performed during hospital stay to gather information on patient characteristics and smoking history. Changes in smoking habits were assessed through telephone interviews at 3, at 6, and at 12 months after cancer diagnosis. RESULTS: Among 1011 enrolled patients, 222 (22%) were current smokers at cancer diagnosis. Smoking prevalence was high in male patients (30%), in patients <50 years old (28%), in those with aerodigestive cancers (50%), and in those diagnosed at advanced stages (26%). Among current smokers at cancer diagnosis, 38% quit smoking after 12 months, 26% reduced intensity, and 36% did not modify smoking habits. Smoking cessation was associated with chemotherapy and, although not statistically significant, with female sex, older age, and advanced cancer stage. Patients with gastrointestinal, breast, or genitourinary cancer and those treated with surgery were less likely to quit smoking. CONCLUSIONS: Our results highlighted that 62% of smoking patients with cancer did not quit the habit. Smoking cessation programs targeted to patients with cancer need intensification, particularly for those who may underestimate smoking effects after diagnosis.


Assuntos
Neoplasias , Abandono do Hábito de Fumar , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Neoplasias/etiologia , Prevalência , Estudos Prospectivos , Fumar/efeitos adversos , Fumar/epidemiologia , Abandono do Hábito de Fumar/métodos
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