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1.
Mol Cancer ; 23(1): 105, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755661

RESUMEN

BACKGROUND: The main drawback of BRAF/MEK inhibitors (BRAF/MEKi)-based targeted therapy in the management of BRAF-mutated cutaneous metastatic melanoma (MM) is the development of therapeutic resistance. We aimed to assess in this context the role of mTORC2, a signaling complex defined by the presence of the essential RICTOR subunit, regarded as an oncogenic driver in several tumor types, including MM. METHODS: After analyzing The Cancer Genome Atlas MM patients' database to explore both overall survival and molecular signatures as a function of intra-tumor RICTOR levels, we investigated the effects of RICTOR downregulation in BRAFV600E MM cell lines on their response to BRAF/MEKi. We performed proteomic screening to identify proteins modulated by changes in RICTOR expression, and Seahorse analysis to evaluate the effects of RICTOR depletion on mitochondrial respiration. The combination of BRAFi with drugs targeting proteins and processes emerged in the proteomic screening was carried out on RICTOR-deficient cells in vitro and in a xenograft setting in vivo. RESULTS: Low RICTOR levels in BRAF-mutated MM correlate with a worse clinical outcome. Gene Set Enrichment Analysis of low-RICTOR tumors display gene signatures suggestive of activation of the mitochondrial Electron Transport Chain (ETC) energy production. RICTOR-deficient BRAFV600E cells are intrinsically tolerant to BRAF/MEKi and anticipate the onset of resistance to BRAFi upon prolonged drug exposure. Moreover, in drug-naïve cells we observed a decline in RICTOR expression shortly after BRAFi exposure. In RICTOR-depleted cells, both mitochondrial respiration and expression of nicotinamide phosphoribosyltransferase (NAMPT) are enhanced, and their pharmacological inhibition restores sensitivity to BRAFi. CONCLUSIONS: Our work unveils an unforeseen tumor-suppressing role for mTORC2 in the early adaptation phase of BRAFV600E melanoma cells to targeted therapy and identifies the NAMPT-ETC axis as a potential therapeutic vulnerability of low RICTOR tumors. Importantly, our findings indicate that the evaluation of intra-tumor RICTOR levels has a prognostic value in metastatic melanoma and may help to guide therapeutic strategies in a personalized manner.


Asunto(s)
Resistencia a Antineoplásicos , Diana Mecanicista del Complejo 2 de la Rapamicina , Melanoma , Inhibidores de Proteínas Quinasas , Proteínas Proto-Oncogénicas B-raf , Proteína Asociada al mTOR Insensible a la Rapamicina , Humanos , Proteína Asociada al mTOR Insensible a la Rapamicina/metabolismo , Proteína Asociada al mTOR Insensible a la Rapamicina/genética , Melanoma/genética , Melanoma/tratamiento farmacológico , Melanoma/metabolismo , Melanoma/patología , Proteínas Proto-Oncogénicas B-raf/genética , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo , Diana Mecanicista del Complejo 2 de la Rapamicina/genética , Resistencia a Antineoplásicos/genética , Ratones , Animales , Línea Celular Tumoral , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto , Regulación Neoplásica de la Expresión Génica , Mutación , Regulación hacia Abajo , Proteómica/métodos
2.
Int J Mol Sci ; 25(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38612380

RESUMEN

Inflammatory bowel diseases (IBD) comprise chronic debilitating inflammatory disorders that can affect different parts of the gastrointestinal tract and are commonly correlated to two main diseases: Crohn's disease (CD) and ulcerative colitis (UC) [...].


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , Humanos , Enfermedades Inflamatorias del Intestino/etiología , Dieta
3.
Pharmaceuticals (Basel) ; 16(2)2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-37259338

RESUMEN

The prevention of nicotinamide adenine dinucleotide (NAD) biosynthesis is considered an attractive therapeutic approach against cancer, considering that tumor cells are characterized by an increased need for NAD to fuel their reprogrammed metabolism. On the other hand, the decline of NAD is a hallmark of some pathological conditions, including neurodegeneration and metabolic diseases, and boosting NAD biosynthesis has proven to be of therapeutic relevance. Therefore, targeting the enzymes nicotinamide phosphoribosyltransferase (NAMPT) and nicotinate phosphoribosyltransferase (NAPRT), which regulate NAD biosynthesis from nicotinamide (NAM) and nicotinic acid (NA), respectively, is considered a promising strategy to modulate intracellular NAD pool. While potent NAMPT inhibitors and activators have been developed, the search for NAPRT modulators is still in its infancy. In this work, we report on the identification of a new class of NAPRT modulators bearing the 1,2-dimethylbenzimidazole scaffold properly substituted in position 5. In particular, compounds 24, 31, and 32 emerged as the first NAPRT activators reported so far, while 18 behaved as a noncompetitive inhibitor toward NA (Ki = 338 µM) and a mixed inhibitor toward phosphoribosyl pyrophosphate (PRPP) (Ki = 134 µM). From in vitro pharmacokinetic studies, compound 18 showed an overall good ADME profile. To rationalize the obtained results, docking studies were performed on the NAPRT structure. Moreover, a preliminary pharmacophore model was built to shed light on the shift from inhibitors to activators.

4.
Molecules ; 28(3)2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36770640

RESUMEN

The maintenance of a proper NAD+ pool is essential for cell survival, and tumor cells are particularly sensitive to changes in coenzyme levels. In this view, the inhibition of NAD+ biosynthesis is considered a promising therapeutic approach. Current research is mostly focused on targeting the enzymes nicotinamide phosphoribosyltransferase (NAMPT) and nicotinate phosphoribosyltransferase (NAPRT), which regulate NAD+ biosynthesis from nicotinamide and nicotinic acid, respectively. In several types of cancer cells, both enzymes are relevant for NAD+ biosynthesis, with NAPRT being responsible for cell resistance to NAMPT inhibition. While potent NAMPT inhibitors have been developed, only a few weak NAPRT inhibitors have been identified so far, essentially due to the lack of an easy and fast screening assay. Here we present a continuous coupled fluorometric assay whereby the product of the NAPRT-catalyzed reaction is enzymatically converted to NADH, and NADH formation is measured fluorometrically. The assay can be adapted to screen compounds that interfere with NADH excitation and emission wavelengths by coupling NADH formation to the cycling reduction of resazurin to resorufin, which is monitored at longer wavelengths. The assay system was validated by confirming the inhibitory effect of some NA-related compounds on purified human recombinant NAPRT. In particular, 2-hydroxynicotinic acid, 2-amminonicotinic acid, 2-fluoronicotinic acid, pyrazine-2-carboxylic acid, and salicylic acid were confirmed as NAPRT inhibitors, with Ki ranging from 149 to 348 µM. Both 2-hydroxynicotinic acid and pyrazine-2-carboxylic acid were found to sensitize OVCAR-5 cells to the NAMPT inhibitor FK866 by decreasing viability and intracellular NAD+ levels.


Asunto(s)
NAD , Niacina , Humanos , NAD/metabolismo , Línea Celular Tumoral , Pentosiltransferasa , Nicotinamida Fosforribosiltransferasa , Citocinas/metabolismo , Niacina/farmacología
5.
Elife ; 112022 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-36476387

RESUMEN

Axon degeneration contributes to the disruption of neuronal circuit function in diseased and injured nervous systems. Severed axons degenerate following the activation of an evolutionarily conserved signaling pathway, which culminates in the activation of SARM1 in mammals to execute the pathological depletion of the metabolite NAD+. SARM1 NADase activity is activated by the NAD+ precursor nicotinamide mononucleotide (NMN). In mammals, keeping NMN levels low potently preserves axons after injury. However, it remains unclear whether NMN is also a key mediator of axon degeneration and dSarm activation in flies. Here, we demonstrate that lowering NMN levels in Drosophila through the expression of a newly generated prokaryotic NMN-Deamidase (NMN-D) preserves severed axons for months and keeps them circuit-integrated for weeks. NMN-D alters the NAD+ metabolic flux by lowering NMN, while NAD+ remains unchanged in vivo. Increased NMN synthesis by the expression of mouse nicotinamide phosphoribosyltransferase (mNAMPT) leads to faster axon degeneration after injury. We also show that NMN-induced activation of dSarm mediates axon degeneration in vivo. Finally, NMN-D delays neurodegeneration caused by loss of the sole NMN-consuming and NAD+-synthesizing enzyme dNmnat. Our results reveal a critical role for NMN in neurodegeneration in the fly, which extends beyond axonal injury. The potent neuroprotection by reducing NMN levels is similar to the interference with other essential mediators of axon degeneration in Drosophila.


Asunto(s)
Drosophila , Mononucleótido de Nicotinamida , Animales , Ratones , Drosophila/metabolismo , Mononucleótido de Nicotinamida/metabolismo , NAD/metabolismo , Axones/fisiología , Neuronas/fisiología , Mamíferos/metabolismo , Proteínas del Citoesqueleto/metabolismo , Proteínas del Dominio Armadillo/genética , Proteínas del Dominio Armadillo/metabolismo
6.
J Struct Biol ; 214(4): 107917, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36332744

RESUMEN

Nicotinamide-adenine dinucleotide (NAD) is centrally important to metabolic reactions that involve redox chemistry. In bacteria, NAD biosynthesis is controlled by different transcription factors, depending on the species. Among the four regulators identified so far, the protein NadQ is reported to act as a repressor of the de novo NAD biosynthetic pathway in proteobacteria. Using comparative genomics, a systematic reconstruction of NadQ regulons in thousands of fully sequenced bacterial genomes has been performed, confirming that NadQ is present in α-proteobacteria and some ß- and γ-proteobacteria, including pathogens like Bordetella pertussis and Neisseria meningitidis, where it likely controls de novo NAD biosynthesis. Through mobility shift assay and mutagenesis, the DNA binding activity of NadQ from Agrobacterium tumefaciens was experimentally validated and determined to be suppressed by ATP. The crystal structures of NadQ in native form and in complex with ATP were determined, indicating that NadQ is a dimer, with each monomer composed of an N-terminal Nudix domain hosting the effector binding site and a C-terminal winged helix-turn-helix domain that binds DNA. Within the dimer, we found one ATP molecule bound, at saturating concentration of the ligand, in keeping with an intrinsic asymmetry of the quaternary structure. Overall, this study provided the basis for depicting a working model of NadQ regulation mechanism.


Asunto(s)
Bacterias , NAD , Adenosina Trifosfato
7.
Food Res Int ; 158: 111592, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35840266

RESUMEN

In Western and Central Mediterranean countries proteases from wild herbaceous perennial plants commonly known as "thistles" have been used as milk coagulants in cheese-making for centuries. For the first time, the technological and biochemical traits of proteases from cultivated Onopordum tauricum Willd. (Taurian thistle, bull cottonthistle) were assessed. The optimal conditions for minimizing the clotting time and the non-specific proteolytic activity were estimated at the highest (T = 43-45 °C; [Ca2+] = 11-13 mM) and the lowest (T = 35-39 °C; [Ca2+] = 5 mM) temperature and calcium ion levels in the explored range respectively, thus highlighting the difficulty to set the best operative compromise in the first step of cheesemaking. In the conditions adopted in common cheesemaking practice (T = 37 °C; pH = 6.5) 1 mL of reconstituted extract from cultivated thistles coagulated 10 mL of ewe's and goat's milk in 114-146 and 129-167 s, respectively, and 1 mL of reconstituted extract from spontaneous thistles coagulated 10 mL of ewe's and goat's milk in 232-294 and 428-621 s, respectively, while no significant differences in the non-specific proteolytic activity between cultivated and spontaneous O. tauricum extracts were observed. The purified enzyme (tauricosin) was identified as an aspartic protease made up of two sub-units with molecular weights of 32 and 9.6 kDa, respectively. Experimental data encouraged the exploitation of O. tauricum as a new and sustainable non-food crop in marginal and rainfed lands of Mediterranean countries, thus reducing the potential biodiversity losses due to wild collection.


Asunto(s)
Queso , Onopordum , Animales , Bovinos , Masculino , Leche/química , Péptido Hidrolasas
8.
Front Mol Biosci ; 9: 834700, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35463964

RESUMEN

Human α-amino-ß-carboxymuconate-ε-semialdehyde decarboxylase (ACMSD) stands at a branch point of the de novo NAD+ synthesis pathway and plays an important role in maintaining NAD+ homeostasis. It has been recently identified as a novel therapeutic target for a wide range of diseases, including inflammatory, metabolic disorders, and aging. So far, in absence of potent and selective enzyme inhibitors, only a crystal structure of the complex of human dimeric ACMSD with pseudo-substrate dipicolinic acid has been resolved. In this study, we report the crystal structure of the complex of human dimeric ACMSD with TES-1025, the first nanomolar inhibitor of this target, which shows a binding conformation different from the previously published predicted binding mode obtained by docking experiments. The inhibitor has a K i value of 0.85 ± 0.22 nM and binds in the catalytic site, interacting with the Zn2+ metal ion and with residues belonging to both chains of the dimer. The results provide new structural information about the mechanism of inhibition exerted by a novel class of compounds on the ACMSD enzyme, a novel therapeutic target for liver and kidney diseases.

9.
J Biol Chem ; 298(3): 101669, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35120922

RESUMEN

The secreted form of the enzyme nicotinamide phosphoribosyltransferase (NAMPT), which catalyzes a key reaction in intracellular NAD biosynthesis, acts as a damage-associated molecular pattern triggering Toll-like receptor 4 (TLR4)-mediated inflammatory responses. However, the precise mechanism of interaction is unclear. Using an integrated approach combining bioinformatics and functional and structural analyses, we investigated the interaction between NAMPT and TLR4 at the molecular level. Starting from previous evidence that the bacterial ortholog of NAMPT cannot elicit the inflammatory response, despite a high degree of structural conservation, two positively charged areas unique to the human enzyme (the α1-α2 and ß1-ß2 loops) were identified as likely candidates for TLR4 binding. However, alanine substitution of the positively charged residues within these loops did not affect either the oligomeric state or the catalytic efficiency of the enzyme. The kinetics of the binding of wildtype and mutated NAMPT to biosensor-tethered TLR4 was analyzed. We found that mutations in the α1-α2 loop strongly decreased the association rate, increasing the KD value from 18 nM, as determined for the wildtype, to 1.3 µM. In addition, mutations in the ß1-ß2 loop or its deletion increased the dissociation rate, yielding KD values of 0.63 and 0.22 µM, respectively. Mutations also impaired the ability of NAMPT to trigger the NF-κB inflammatory signaling pathway in human cultured macrophages. Finally, the involvement of the two loops in receptor binding was supported by NAMPT-TLR4 docking simulations. This study paves the way for future development of compounds that selectively target eNAMPT/TLR4 signaling in inflammatory disorders.


Asunto(s)
Citocinas , Nicotinamida Fosforribosiltransferasa , Receptor Toll-Like 4 , Citocinas/genética , Citocinas/metabolismo , Humanos , NAD/metabolismo , FN-kappa B/metabolismo , Nicotinamida Fosforribosiltransferasa/genética , Nicotinamida Fosforribosiltransferasa/metabolismo , Unión Proteica , Transducción de Señal , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo
10.
Int J Biochem Cell Biol ; 145: 106189, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35219878

RESUMEN

Nicotinamide phosphoribosyltransferase (NAMPT) possesses a vital role in mammalian cells due to its activity as a rate-limiting enzyme in the biosynthesis of nicotinamide adenine dinucleotide (NAD) from nicotinamide. NAD is an essential redox cofactor, but it also functions as a substrate for NAD-consuming enzymes, regulating multiple cellular processes such as DNA repair and gene expression, fundamental to sustain tumor growth and survival and energetic needs. A common strategy that several tumor types adopt to sustain NAD synthesis is to over-express NAMPT. However, beside its intracellular functions, this enzyme has a second life outside of cells exerting cytokine-like functions and mediating pro-inflammatory conditions activating signaling pathways. While the effects of NAMPT/NAD axis on energetic metabolism in tumors has been well-established, increasing evidence demonstrated the impact of NAMPT over-expression (intra-/extra-cellular) on several tumor cellular processes, including DNA repair, gene expression, signaling pathways, proliferation, invasion, stemness, phenotype plasticity, metastatization, angiogenesis, immune regulation, and drug resistance. For all these reasons, NAMPT targeting has emerged as promising anti-cancer strategy to deplete NAD and impair cellular metabolism, but also to counteract the other NAMPT-related functions. In this review, we summarize the key role of NAMPT in multiple biological processes implicated in cancer biology and the impact of NAMPT inhibition as therapeutic strategy for cancer treatment.


Asunto(s)
Neoplasias , Nicotinamida Fosforribosiltransferasa , Animales , Citocinas/metabolismo , Mamíferos/metabolismo , NAD/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Niacinamida , Nicotinamida Fosforribosiltransferasa/genética , Nicotinamida Fosforribosiltransferasa/metabolismo
11.
Cell Mol Life Sci ; 78(7): 3317-3331, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33755743

RESUMEN

Extracellular NAD represents a key signaling molecule in different physiological and pathological conditions. It exerts such function both directly, through the activation of specific purinergic receptors, or indirectly, serving as substrate of ectoenzymes, such as CD73, nucleotide pyrophosphatase/phosphodiesterase 1, CD38 and its paralog CD157, and ecto ADP ribosyltransferases. By hydrolyzing NAD, these enzymes dictate extracellular NAD availability, thus regulating its direct signaling role. In addition, they can generate from NAD smaller signaling molecules, like the immunomodulator adenosine, or they can use NAD to ADP-ribosylate various extracellular proteins and membrane receptors, with significant impact on the control of immunity, inflammatory response, tumorigenesis, and other diseases. Besides, they release from NAD several pyridine metabolites that can be taken up by the cell for the intracellular regeneration of NAD itself. The extracellular environment also hosts nicotinamide phosphoribosyltransferase and nicotinic acid phosphoribosyltransferase, which inside the cell catalyze key reactions in NAD salvaging pathways. The extracellular forms of these enzymes behave as cytokines, with pro-inflammatory functions. This review summarizes the current knowledge on the extracellular NAD metabolome and describes the major biochemical properties of the enzymes involved in extracellular NAD metabolism, focusing on the contribution of their catalytic activities to the biological function. By uncovering the controversies and gaps in their characterization, further research directions are suggested, also to better exploit the great potential of these enzymes as therapeutic targets in various human diseases.


Asunto(s)
ADP Ribosa Transferasas/metabolismo , Enfermedad , Metaboloma , NAD/metabolismo , Pentosiltransferasa/metabolismo , Pirofosfatasas/metabolismo , Animales , Humanos , Transducción de Señal
12.
J Bacteriol ; 202(10)2020 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-32152217

RESUMEN

Diadenosine tetraphosphate (Ap4A) is a dinucleotide found in both prokaryotes and eukaryotes. In bacteria, its cellular levels increase following exposure to various stress signals and stimuli, and its accumulation is generally correlated with increased sensitivity to a stressor(s), decreased pathogenicity, and enhanced antibiotic susceptibility. Ap4A is produced as a by-product of tRNA aminoacylation, and is cleaved to ADP molecules by hydrolases of the ApaH and Nudix families and/or by specific phosphorylases. Here, considering evidence that the recombinant protein YqeK from Staphylococcus aureus copurified with ADP, and aided by thermal shift and kinetic analyses, we identified the YqeK family of proteins (COG1713) as an unprecedented class of symmetrically cleaving Ap4A hydrolases. We validated the functional assignment by confirming the ability of YqeK to affect in vivo levels of Ap4A in B. subtilis YqeK shows a catalytic efficiency toward Ap4A similar to that of the symmetrically cleaving Ap4A hydrolases of the known ApaH family, although it displays a distinct fold that is typical of proteins of the HD domain superfamily harboring a diiron cluster. Analysis of the available 3D structures of three members of the YqeK family provided hints to the mode of substrate binding. Phylogenetic analysis revealed the occurrence of YqeK proteins in a consistent group of Gram-positive bacteria that lack ApaH enzymes. Comparative genomics highlighted that yqeK and apaH genes share a similar genomic context, where they are frequently found in operons involved in integrated responses to stress signals.IMPORTANCE Elevation of Ap4A level in bacteria is associated with increased sensitivity to heat and oxidative stress, reduced antibiotic tolerance, and decreased pathogenicity. ApaH is the major Ap4A hydrolase in gamma- and betaproteobacteria and has been recently proposed as a novel target to weaken the bacterial resistance to antibiotics. Here, we identified the orphan YqeK protein family (COG1713) as a highly efficient Ap4A hydrolase family, with members distributed in a consistent group of bacterial species that lack the ApaH enzyme. Among them are the pathogens Staphylococcus aureus, Streptococcus pneumoniae, and Mycoplasma pneumoniae By identifying the player contributing to Ap4A homeostasis in these bacteria, we disclose a novel target to develop innovative antibacterial strategies.


Asunto(s)
Ácido Anhídrido Hidrolasas/metabolismo , Proteínas Bacterianas/metabolismo , Staphylococcus aureus/enzimología , Ácido Anhídrido Hidrolasas/química , Ácido Anhídrido Hidrolasas/genética , Adenosina Difosfato/metabolismo , Secuencia de Aminoácidos , Bacterias/química , Bacterias/clasificación , Bacterias/enzimología , Bacterias/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Catálisis , Clonación Molecular , Fosfatos de Dinucleósidos/química , Fosfatos de Dinucleósidos/metabolismo , Cinética , Familia de Multigenes , Filogenia , Alineación de Secuencia , Staphylococcus aureus/química , Staphylococcus aureus/genética
13.
Antioxidants (Basel) ; 9(1)2020 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-31936782

RESUMEN

: Manuka honey (MH) is a natural food with many beneficial properties to human health, thanks to its high variety of bioactive compounds; however, little is known about its bioaccessibility. The aim of this study was to evaluate and compare the polyphenol compounds, the antioxidant capacity and the anticancer activity of MH subjected to an in vitro gastrointestinal digestion in human HCT-116 colon cancer cells. Raw MH and digested MH (DMH) were assessed for total polyphenols and flavonoids by spectrophotometric and HPLC-ESI-MS/MS analysis, and total antioxidant capacity (TAC) using different methods. Cell viability, intracellular ROS production, apoptosis, cell cycle and colony formation capacity were tested after treatment with MH or DMH. Results showed that total polyphenols, total flavonoids and TAC were significantly (p < 0.05) reduced after in vitro digestion. In addition, MH and DMH at 8, 16 and 24 mg/mL had similar effects in inducing intracellular ROS production and in inhibiting the colon formation ability; MH induced a more marked apoptosis compared to DMH, while cell cycle was blocked in S phase by MH and in Sub G1 phase by DMH. Our results increase knowledge of the effect of gastrointestinal digestion on the biological effect of honey against colorectal cancer.

14.
Biotechnol Adv ; 38: 107322, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-30476540

RESUMEN

Worldwide, colorectal cancer (CRC) remains a major cancer type and leading cause of death. Unfortunately, current medical treatments are not sufficient due to lack of effective therapy, adverse side effects, chemoresistance and disease recurrence. In recent decades, epidemiologic observations have highlighted the association between the ingestion of several phytochemical-enriched foods and nutrients and the lower risk of CRC. According to preclinical studies, dietary phytochemicals exert chemopreventive effects on CRC by regulating different markers and signaling pathways; additionally, the gut microbiota plays a role as vital effector in CRC onset and progression, therefore, any dietary alterations in it may affect CRC occurrence. A high number of studies have displayed a key role of growth factors and their signaling pathways in the pathogenesis of CRC. Indeed, the efficiency of dietary phytochemicals to modulate carcinogenic processes through the alteration of different molecular targets, such as Wnt/ß-catenin, PI3K/Akt/mTOR, MAPK (p38, JNK and Erk1/2), EGFR/Kras/Braf, TGF-ß/Smad2/3, STAT1-STAT3, NF-кB, Nrf2 and cyclin-CDK complexes, has been proven, whereby many of these targets also represent the backbone of modern drug discovery programs. Furthermore, epigenetic analysis showed modified or reversed aberrant epigenetic changes exerted by dietary phytochemicals that led to possible CRC prevention or treatment. Therefore, our aim is to discuss the effects of some common dietary phytochemicals that might be useful in CRC as preventive or therapeutic agents. This review will provide new guidance for research, in order to identify the most studied phytochemicals, their occurrence in foods and to evaluate the therapeutic potential of dietary phytochemicals for the prevention or treatment of CRC by targeting several genes and signaling pathways, as well as epigenetic modifications. In addition, the results obtained by recent investigations aimed at improving the production of these phytochemicals in genetically modified plants have been reported. Overall, clinical data on phytochemicals against CRC are still not sufficient and therefore the preventive impacts of dietary phytochemicals on CRC development deserve further research so as to provide additional insights for human prospective studies.


Asunto(s)
Neoplasias Colorrectales , Anticarcinógenos , Humanos , Fosfatidilinositol 3-Quinasas , Fitoquímicos , Estudios Prospectivos
15.
Food Funct ; 10(11): 7103-7120, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31621765

RESUMEN

The aim of this study was the evaluation of the effects of strawberry anthocyanin extract treatment on two in vitro models of murine breast cancer cell lines, in an attempt to detect a specific pathway (AMP-activated protein kinase or AMPK) through which strawberries exert their anticancer activity. The anticancer activity of purified anthocyanin extracts from an Alba cultivar on two murine cancer cell lines, N202/1A (with high levels of the HER2/neu oncogene) and N202/1E (with low levels of the HER2/neu oncogene), was evaluated after 48 and 72 h of treatment. The cell viability and apoptosis, intracellular ROS rates, and cell oxidative damage were assessed. Western blot assays were performed to analyze the expression of several proteins related to apoptosis, autophagy, metastasis, the oxidative status, mitochondrial functionality, and the AMPK pathway. This study demonstrated that the anthocyanin extract of Alba strawberry shows an antiproliferative effect on cancer cells, through the induction of apoptosis and oxidative stress, by stimulating different molecular pathways. This study is one of the first studies that have tried to deepen the understanding of a candidate pathway for the explanation of the effects of strawberry on cancer cells. A relationship between the AMPK pathway and the anticancer effects of strawberries was demonstrated.


Asunto(s)
Antocianinas/farmacología , Neoplasias de la Mama/fisiopatología , Fragaria/química , Extractos Vegetales/farmacología , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Antocianinas/aislamiento & purificación , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/aislamiento & purificación , Especies Reactivas de Oxígeno/metabolismo
16.
Artículo en Inglés | MEDLINE | ID: mdl-31561897

RESUMEN

Phenolic groups of steroidal or nonsteroidal estrogens can redox cycle, leading to oxidative stress, where creation of reactive oxygen species are recognized as the main mechanism of their DNA damage properties. Dry olive (Olea europaea L.) leaf extract is known to contain bioactive and antioxidative components and to have an ability to modulate the effects of various oxidants in cells. The main goal of this study was to investigate antigenotoxic potential of a standardized dry olive leaf extract on DNA damage induced by 17ß-estradiol and diethylstilbestrol in human whole blood cells in vitro, using comet assay. Our results indicated that both hormones showed a genotoxic effect at a concentration of 100 µM (P < 0.05, n = 6). Dry olive leaf extract was efficient in reducing number of cells with estrogen-induced DNA damage at tested concentrations (0.125, 0.5 and 1 mg/mL) (P < 0.05, n = 6) and under two experimental protocols, pre-treatment and post-treatment, exhibiting antigenotoxic properties. Analysis of antioxidant properties of the extract revealed moderate ABTS radical scavenging properties and reducing power. Overall, our results suggested that the protective potential of dry olive leaf extract could arise from the synergistic effect of its scavenging activity and enhancement of the cells' antioxidant capacity.


Asunto(s)
Antioxidantes/farmacología , Células Sanguíneas/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Dietilestilbestrol/antagonistas & inhibidores , Estradiol/toxicidad , Antagonistas de Estrógenos/farmacología , Depuradores de Radicales Libres/farmacología , Olea/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Adulto , Ensayo Cometa , Dietilestilbestrol/toxicidad , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Femenino , Humanos , Masculino , Oxidación-Reducción , Estrés Oxidativo , Extractos Vegetales/aislamiento & purificación , Especies Reactivas de Oxígeno , Adulto Joven
17.
Antioxid Redox Signal ; 30(4): 577-634, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29943652

RESUMEN

SIGNIFICANCE: In eukaryotes, autophagy represents a highly evolutionary conserved process, through which macromolecules and cytoplasmic material are degraded into lysosomes and recycled for biosynthetic or energetic purposes. Dysfunction of the autophagic process has been associated with the onset and development of many human chronic pathologies, such as cardiovascular, metabolic, and neurodegenerative diseases as well as cancer. Recent Advances: Currently, comprehensive research is being carried out to discover new therapeutic agents that are able to modulate the autophagic process in vivo. Recent evidence has shown that a large number of natural bioactive compounds are involved in the regulation of autophagy by modulating several transcriptional factors and signaling pathways. CRITICAL ISSUES: Critical issues that deserve particular attention are the inadequate understanding of the complex role of autophagy in disease pathogenesis, the limited availability of therapeutic drugs, and the lack of clinical trials. In this context, the effects that natural bioactive compounds exert on autophagic modulation should be clearly highlighted, since they depend on the type and stage of the pathological conditions of diseases. FUTURE DIRECTIONS: Research efforts should now focus on understanding the survival-supporting and death-promoting roles of autophagy, how natural compounds interact exactly with the autophagic targets so as to induce or inhibit autophagy and on the evaluation of their pharmacological effects in a more in-depth and mechanistic way. In addition, clinical studies on autophagy-inducing natural products are strongly encouraged, also to highlight some fundamental aspects, such as the dose, the duration, and the possible synergistic action of these compounds with conventional therapy.


Asunto(s)
Autofagia/efectos de los fármacos , Productos Biológicos/farmacología , Neoplasias/tratamiento farmacológico , Productos Biológicos/química , Humanos , Enfermedades del Sistema Inmune/tratamiento farmacológico , Enfermedades del Sistema Inmune/patología , Enfermedades Metabólicas/tratamiento farmacológico , Enfermedades Metabólicas/patología , Neoplasias/patología , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/patología
18.
J Cell Physiol ; 234(5): 7622-7633, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30317591

RESUMEN

Uterine leiom yomas are benign tumors highly prevalent in reproductive women. In thecurrent study, initially, we aimed to screen five different strawberry cultivars (Alba, Clery, Portola, Tecla, and Romina) to identify efficient cultivars in terms of phytochemical characterization and biological properties by measuring phenolic and anthocyanin content as well as antioxidant capacity, and by measuring apoptotic rate and reactive oxygen species (ROS) production in uterine leiomyoma cells. Next, we focused on the most efficient ones, cultivar Alba (A) and Romina (R) as well as Romina anthocyanin (RA) fraction for their ability to regulate oxidative phosphorylation (oxygen consumption rate [OCR]) glycolysis (extracellular acidification rate [ECAR]), and also fibrosis. Leiomyoma and myometrial cells were treated with a methanolic extract of A and R (250 µg/ml) or with RA (50 µg/ml) for 48 hr to measure OCR and ECAR, as well as gene expression associated with fibrosis. In the leiomyoma cells, RA was more effective in inducing apoptosis and increasing intracellular ROS levels, followed by R and A. In myometrial cells, all strawberry treatments increased the cellular viability and decreased ROS concentrations. Leiomyoma cells showed also a significant decrease in ECAR, especially after RA treatment, while OCR was slightly increased in both myometrial and leiomyoma cells. R and RA treatment significantly decreased collagen 1A1, fibronectin, versican, and activin A messenger RNA expression in leiomyoma cells. In conclusion, this study suggests that Romina, or its anthocyanin fraction, can be developed as a therapeutic and/or preventive agent for uterine leiomyomas, confirming the healthy effects exerted by these fruits and their bioactive compounds.


Asunto(s)
Fragaria/química , Leiomioma/tratamiento farmacológico , Preparaciones de Plantas/farmacología , Neoplasias Uterinas/tratamiento farmacológico , Activinas/farmacología , Antioxidantes/metabolismo , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colágeno Tipo I/metabolismo , Femenino , Fibronectinas/metabolismo , Fibrosis/tratamiento farmacológico , Fibrosis/metabolismo , Expresión Génica/efectos de los fármacos , Glucólisis/efectos de los fármacos , Humanos , Leiomioma/metabolismo , Fosforilación Oxidativa/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Células Tumorales Cultivadas , Neoplasias Uterinas/metabolismo , Versicanos/farmacología
19.
Crit Rev Food Sci Nutr ; 59(6): 893-920, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30421983

RESUMEN

The traditional Mediterranean diet (MedDiet) is a well-known dietary pattern associated with longevity and improvement of life quality as it reduces the risk of the most common chronic pathologies, such as cancer and cardiovascular diseases (CVDs), that represent the principal cause of death worldwide. One of the most characteristic foods of MedDiet is olive oil, a very complex matrix, which constitutes the main source of fats and is used in the preparation of foods, both raw as an ingredient in recipes, and in cooking. Similarly, strawberries and raspberries are tasty and powerful foods which are commonly consumed in the Mediterranean area in fresh and processed forms and have attracted the scientific and consumer attention worldwide for their beneficial properties for human health. Besides olive oil and berries, honey has lately been introduced in the MedDiet thanks to its relevant nutritional, phytochemical and antioxidant profile. It is a sweet substance that has recently been classified as a functional food. The aim of this review is to present and discuss the recent evidence, obtained from in vitro, in vivo and epidemiological studies, on the potential roles exerted by these foods in the prevention and progression of different types of cancer and CVDs.


Asunto(s)
Dieta Mediterránea , Frutas , Alimentos Funcionales/análisis , Miel , Aceite de Oliva/administración & dosificación , Animales , Enfermedades Cardiovasculares/prevención & control , Modelos Animales de Enfermedad , Humanos , Longevidad , Neoplasias/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto
20.
Int J Mol Sci ; 19(9)2018 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-30235888

RESUMEN

The antioxidant capacity and the phytochemical composition of two by-products from beeswax recycling processes were recently investigated. The aim of the present work was to evaluate the efficacy of one of these by-products, MUD1, against the oxidative stress induced by 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) in human dermal fibroblast (HDF) cells. After a preliminary viability assay, the protective effect of MUD1 was investigated through the measurement of apoptosis level, the reactive oxygen species (ROS) and nitrite (NO2-) production, the level of protein and lipid biomarkers (carbonyl groups, total glutathione and thiobarbituric acid-reactive substance) of oxidative damage, and the measurement of antioxidant enzymes activities (glutatione peroxidase, glutathione reductase, glutathione transferase, superoxide dismutase and catalase). The obtained results showed that MUD1 exerted protective effects on HDF, increasing cell viability and counteracted the oxidative stress promoted by AAPH-treatment, and improved mitochondria functionality and wound healing capacities. This work shows the antioxidant effects exerted by beeswax by-products, demonstrating for the first time their potential against oxidative stress in human dermal fibroblast cells; however, further research will be necessary to evaluate their potentiality for human health by more deeply in vitro and in vivo studies.


Asunto(s)
Antioxidantes/farmacología , Fibroblastos/efectos de los fármacos , Ceras/farmacología , Apoptosis , Células Cultivadas , Dermis/citología , Fibroblastos/metabolismo , Humanos , Estrés Oxidativo , Ceras/química
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