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1.
Cell ; 174(2): 271-284.e14, 2018 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-29887373

RESUMO

The small intestinal tuft cell-ILC2 circuit mediates epithelial responses to intestinal helminths and protists by tuft cell chemosensory-like sensing and IL-25-mediated activation of lamina propria ILC2s. Small intestine ILC2s constitutively express the IL-25 receptor, which is negatively regulated by A20 (Tnfaip3). A20 deficiency in ILC2s spontaneously triggers the circuit and, unexpectedly, promotes adaptive small-intestinal lengthening and remodeling. Circuit activation occurs upon weaning and is enabled by dietary polysaccharides that render mice permissive for Tritrichomonas colonization, resulting in luminal accumulation of acetate and succinate, metabolites of the protist hydrogenosome. Tuft cells express GPR91, the succinate receptor, and dietary succinate, but not acetate, activates ILC2s via a tuft-, TRPM5-, and IL-25-dependent pathway. Also induced by parasitic helminths, circuit activation and small intestinal remodeling impairs infestation by new helminths, consistent with the phenomenon of concomitant immunity. We describe a metabolic sensing circuit that may have evolved to facilitate mutualistic responses to luminal pathosymbionts.


Assuntos
Intestino Delgado/fisiologia , Tritrichomonas/metabolismo , Acetatos/metabolismo , Animais , Fibras na Dieta/metabolismo , Metabolismo Energético , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Epiteliais/parasitologia , Interleucinas/genética , Interleucinas/metabolismo , Mucosa Intestinal/citologia , Intestino Delgado/microbiologia , Intestino Delgado/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microbiota , Plasmídeos/genética , Plasmídeos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Interleucina/metabolismo , Receptores de Interleucina-17/genética , Receptores de Interleucina-17/metabolismo , Ácido Succínico/metabolismo , Canais de Cátion TRPM/metabolismo , Tritrichomonas/crescimento & desenvolvimento , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo
2.
J Med Virol ; 95(1): e28283, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36333280

RESUMO

We agree that smoking might be a risk factor for the severity of COVID-19, but in our previous study, smoking was not so robust compared with our conclusion. Also, we strongly agreed that COVID-19 patients with diabetes or other chronic diseases might worsen the situation of the disease. But these factors were out of the scope of our study and we had published other research on this topic related to diabetes. Because of the limited sample size and original medical records, our study could not cover many factors. But we wish our study will be a useful and meaningful pilot study for future studies.

3.
Altern Lab Anim ; 51(4): 263-288, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37282515

RESUMO

Animal experimentation has been integral to drug discovery and development and safety assessment for many years, since it provides insights into the mechanisms of drug efficacy and toxicity (e.g. pharmacology, pharmacokinetics and pharmacodynamics). However, due to species differences in physiology, metabolism and sensitivity to drugs, the animal models can often fail to replicate the effects of drugs and chemicals in human patients, workers and consumers. Researchers across the globe are increasingly applying the Three Rs principles by employing innovative methods in research and testing. The Three Rs concept focuses on: the replacement of animal models (e.g. with in vitro and in silico models or human studies), on the reduction of the number of animals required to achieve research objectives, and on the refinement of existing experimental practices (e.g. eliminating distress and enhancing animal wellbeing). For the last two years, Oncoseek Bio-Acasta Health, a 3-D cell culture-based cutting-edge translational biotechnology company, has organised an annual International Conference on 3Rs Research and Progress. This series of global conferences aims to bring together researchers with diverse expertise and interests, and provides a platform where they can share and discuss their research to promote practices according to the Three Rs principles. In November 2022, the 3rd international conference, Advances in Animal Models and Cutting-Edge Research in Alternatives, took place at the GITAM University in Vishakhapatnam (AP, India) in a hybrid format (i.e. online and in-person). These conference proceedings provide details of the presentations, which were categorised under five different topic sessions. It also describes a special interactive session on in silico strategies for preclinical research in oncology, which was held at the end of the first day.


Assuntos
Experimentação Animal , Animais , Humanos , Modelos Animais , Descoberta de Drogas , Índia , Alternativas aos Testes com Animais
4.
J Med Virol ; 94(10): 4727-4734, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35656698

RESUMO

Comorbidities such as hypertension could exacerbate symptoms of coronaviral disease 2019 (COVID)-19 infection. Patients with hypertension may receive both anti-COVID-19 and antihypertension therapies when infected with COVID-19. However, it is not clear how different classes of anti-hypertension drugs impact the outcome of COVID-19 treatment. Herein, we explore the association between the inpatient use of different classes of anti-hypertension drugs and mortality among patients with hypertension hospitalized with COVID-19. We totally collected data from 278 patients with hypertension diagnosed with COVID-19 admitted to hospitals in Wuhan from February 1 to April 1, 2020. A retrospective study was conducted and single-cell RNA-sequencing (RNA-Seq) analysis of treatment-related genes was performed. The results showed that Angiotensin II receptor blocker (ARB) and calcium channel blocker (CCB) drugs significantly increased the survival rate but the use of angiotensin-converting enzyme inhibitor/ß-block/diuretic drugs did not affect the mortality caused by COVID-19. Based on the analysis of four public data sets of single-cell RNA-Seq on COVID-19 patients, we concluded that JUN, LST1 genes may play a role in the effect of ARB on COVID-19-related mortality, whereas CALM1 gene may contribute to the effect of CCB on COVID-19-related mortality. Our results provide guidance on the selection of antihypertension drugs for hypertensive patients infected with COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Hipertensão , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , COVID-19/complicações , Bloqueadores dos Canais de Cálcio/uso terapêutico , Biologia Computacional , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Estudos Retrospectivos , SARS-CoV-2
5.
Molecules ; 27(23)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36500212

RESUMO

Bivalent proximity-inducing compounds represent a novel class of small molecule therapeutics with exciting potential and new challenges. The most prominent examples of such compounds are utilized in targeted protein degradation where E3 ligases are hijacked to recruit a substrate protein to the proteasome via ubiquitination. In this review we provide an overview of the current state of E3 ligases used in targeted protein degradation, their respective ligands as well as challenges and opportunities that present themselves with these compounds.


Assuntos
Complexo de Endopeptidases do Proteassoma , Ubiquitina , Proteólise , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina/metabolismo , Ubiquitinação , Ubiquitina-Proteína Ligases/metabolismo
6.
Bioorg Med Chem Lett ; 29(16): 2286-2289, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31278031

RESUMO

The tumor suppressor transcription factor CCAAT enhancer-binding protein α (C/EBPα) expression is downregulated in myeloid leukemias and enhancement of C/EBPα expression induces granulocytic differentiation in leukemic cells. Previously we reported that Styryl quinazolinones induce myeloid differentiation in HL-60 cells by upregulating C/EBPα expression. To identify more potent molecule that can induce leukemic cell differentiation we synthesized and evaluated new series of styryl quinazolinones, ethynyl styryl quinazolinones, styryl quinolinones and thienopyrimidinones. Thienopyrimidinones were found toxic and styryl quinolinones were found inactive. Ethynyl styryl quinazolinone 39 and styryl quinazolinone 5 were found active on par with the earlier reported analogues 1 and 2 suggesting that the 5-nitro furan-2-yl styryl quinazolinones find a real promise in leukemic cell differentiation. The improved potency of 5 suggested that further modifications in the 5-nitro furan-2-yl styryl quinazolinones can be at the phenyl substitution at the 3-position of the quinazolinone ring apart from the 5-position of the heteroaryl ring.


Assuntos
Alcinos/farmacologia , Antineoplásicos/farmacologia , Proteína alfa Estimuladora de Ligação a CCAAT/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Quinazolinonas/farmacologia , Alcinos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Leucemia Mieloide Aguda/metabolismo , Estrutura Molecular , Quinazolinonas/síntese química , Quinazolinonas/química , Relação Estrutura-Atividade
7.
BMC Complement Altern Med ; 16: 278, 2016 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-27506388

RESUMO

BACKGROUND: We have previously shown that the grape bioactive compound resveratrol (RSV) potentiates grape seed extract (GSE)-induced colon cancer cell apoptosis at physiologically relevant concentrations. However, RSV-GSE combination efficacy against colon cancer stem cells (CSCs), which play a key role in chemotherapy and radiation resistance, is not known. METHODS: We tested the anti-cancer efficacy of the RSV-GSE against colon CSCs using isolated human colon CSCs in vitro and an azoxymethane-induced mouse model of colon carcinogenesis in vivo. RESULTS: RSV-GSE suppressed tumor incidence similar to sulindac, without any gastrointestinal toxicity. Additionally, RSV-GSE treatment reduced the number of crypts containing cells with nuclear ß-catenin (an indicator of colon CSCs) via induction of apoptosis. In vitro, RSV-GSE suppressed - proliferation, sphere formation, nuclear translocation of ß-catenin (a critical regulator of CSC proliferation) similar to sulindac in isolated human colon CSCs. RSV-GSE, but not sulindac, suppressed downstream protein levels of Wnt/ß-catenin pathway, c-Myc and cyclin D1. RSV-GSE also induced mitochondrial-mediated apoptosis in colon CSCs characterized by elevated p53, Bax/Bcl-2 ratio and cleaved PARP. Furthermore, shRNA-mediated knockdown of p53, a tumor suppressor gene, in colon CSCs did not alter efficacy of RSV-GSE. CONCLUSION: The suppression of Wnt/ß-catenin signaling and elevated mitochondrial-mediated apoptosis in colon CSCs support potential clinical testing/application of grape bioactives for colon cancer prevention and/or therapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias do Colo/metabolismo , Extrato de Sementes de Uva/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Vitis/química , Animais , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Extrato de Sementes de Uva/química , Masculino , Camundongos , Células-Tronco Neoplásicas/metabolismo , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Estilbenos/química , Estilbenos/farmacologia , beta Catenina/metabolismo
8.
Bioorg Med Chem Lett ; 25(20): 4412-8, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26386604

RESUMO

Non-basic azolotriazinones were explored using an empirical free brain exposures-driven approach to identify potent MCHR1 antagonists for evaluation in in vivo efficacy studies. An optimized lead from this series, 1j (rMCHR1 Ki=1.8 nM), demonstrated a 6.9% reduction in weight gain relative to vehicle in a rat model at 30 mg/kg after 4 days of once-daily oral treatment as a glycine prodrug. Despite a promising efficacy profile, an assessment of the biliary toxicity risk of this compound rendered this compound non-progressible.


Assuntos
Encéfalo/efeitos dos fármacos , Obesidade/tratamento farmacológico , Receptores de Somatostatina/antagonistas & inibidores , Triazinas/farmacologia , Animais , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Obesidade/metabolismo , Ratos , Relação Estrutura-Atividade , Triazinas/administração & dosagem , Triazinas/química
9.
bioRxiv ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38260640

RESUMO

Immunomodulatory imide drugs (IMiDs) degrade specific C2H2 zinc finger degrons in transcription factors, making them effective against certain cancers. SALL4, a cancer driver, contains seven C2H2 zinc fingers in four clusters, including an IMiD degron in zinc finger cluster two (ZFC2). Surprisingly, IMiDs do not inhibit growth of SALL4 expressing cancer cells. To overcome this limit, we focused on a non-IMiD degron, SALL4 zinc finger cluster four (ZFC4). By combining AlphaFold and the ZFC4-DNA crystal structure, we identified a potential ZFC4 drug pocket. Utilizing an in silico docking algorithm and cell viability assays, we screened chemical libraries and discovered SH6, which selectively targets SALL4-expressing cancer cells. Mechanistic studies revealed that SH6 degrades SALL4 protein through the CUL4A/CRBN pathway, while deletion of ZFC4 abolished this activity. Moreover, SH6 led to significant 62% tumor growth inhibition of SALL4+ xenografts in vivo and demonstrated good bioavailability in pharmacokinetic studies. In summary, these studies represent a new approach for IMiD independent drug discovery targeting C2H2 transcription factors in cancer.

10.
Wound Repair Regen ; 21(1): 1-16, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23126632

RESUMO

Mimicking porous topography of natural extracellular matrix is advantageous for successful regeneration of damaged tissues or organs. Nanotechnology being one of the most promising and growing technology today shows an extremely huge potential in the field of tissue engineering. Nanofibrous structures that mimic the native extracellular matrix and promote the adhesion of various cells are being developed as tissue-engineered scaffolds for skin, bone, vasculature, heart, cornea, nervous system, and other tissues. A range of novel biocomposite materials has been developed to enhance the bioactive or therapeutic properties of these nanofibrous scaffolds via surface modifications, including the immobilization of functional cell-adhesive ligands and bioactive molecules such as drugs, enzymes, and cytokines. In skin tissue engineering, usage of allogeneic skin is avoided to reestablish physiological continuity and also to address the challenge of curing acute and chronic wounds, which remains as the area of exploration with various biomimetic approaches. Two-dimensional, three-dimensional scaffolds and stem cells are presently used as dermal regeneration templates for the treatment of full-thickness skin defects resulting from injuries and severe burns. The present review elaborates specifically on the fabrication of nanofibrous structured strategies for wound dressings, wound healing, and controlled release of growth factors for skin tissue regeneration.


Assuntos
Nanofibras , Nanomedicina/métodos , Pele/lesões , Cicatrização , Ferimentos e Lesões/terapia , Materiais Biocompatíveis , Adesão Celular , Doença Crônica , Humanos , Nanomedicina/tendências , Regeneração , Pele/fisiopatologia , Pele Artificial , Engenharia Tecidual , Alicerces Teciduais
11.
FEBS J ; 290(9): 2437-2448, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36259273

RESUMO

Glutaminase catalyses the metabolic process called glutaminolysis. Cancer cells harness glutaminolysis to increase energy reserves under stressful conditions for rapid proliferation. Glutaminases are upregulated in many tumours. In humans, the kidney-type glutaminase (KGA) isoform is highly expressed in the kidney, brain, intestine, foetal liver, lymphocytes and in many tumours. Glutaminase inhibition is shown to be effective in controlling cancers. Previously, we and others reported the inhibition mechanism of KGA using various inhibitors that target the active and allosteric sites of the enzyme. Here, we report the identification of a novel allosteric site in KGA using the compound DDP through its complex crystal structure combined with mutational and hydrogen-deuterium exchange mass spectrometry studies. This allosteric site is located at the dimer interface, situated ~ 31 Å away from the previously identified allosteric site and ~ 32 Å away from the active site. Remarkably, the mechanism of inhibition is conserved, irrespective of which allosteric pocket is targeted, causing the same conformational changes in the key loop near the active site (Glu312-Pro329) and subsequent enzyme inactivation. Contrary to the previously identified allosteric site, the identified new allosteric site is primarily hydrophilic. This site could be effectively targeted for the synthesis of specific and potent water-soluble inhibitors of glutaminase, which will lead to the development of anticancer drugs.


Assuntos
Antineoplásicos , Glutaminase , Humanos , Sítio Alostérico , Glutaminase/genética , Glutaminase/metabolismo , Rim/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Mutação
12.
Sci Rep ; 12(1): 12707, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35882902

RESUMO

Disinformation campaigns are prevalent, affecting vaccination coverage, creating uncertainty in election results, and causing supply chain disruptions, among others. Unfortunately, the problems of misinformation and disinformation are exacerbated due to the wide availability of online platforms and social networks. Naturally, these emerging disinformation networks could lead users to engage with critical infrastructure systems in harmful ways, leading to broader adverse impacts. One such example involves the spread of false pricing information, which causes drastic and sudden changes in user commodity consumption behavior, leading to shortages. Given this, it is critical to address the following related questions: (i) How can we monitor the evolution of disinformation dissemination and its projected impacts on commodity consumption? (ii) What effects do the mitigation efforts of human intermediaries have on the performance of the infrastructure network subject to disinformation campaigns? (iii) How can we manage infrastructure network operations and counter disinformation in concert to avoid shortages and satisfy user demands? To answer these questions, we develop a hybrid approach that integrates an epidemiological model of disinformation spread (based on a susceptible-infectious-recovered model, or SIR) with an efficient mixed-integer programming optimization model for infrastructure network performance. The goal of the optimization model is to determine the best protection and response actions against disinformation to minimize the general shortage of commodities at different nodes over time. The proposed model is illustrated with a case study involving a subset of the western US interconnection grid located in Los Angeles County in California.


Assuntos
Mídias Sociais , Comunicação , Desinformação , Humanos , Política , Rede Social
13.
Curr Dev Nutr ; 6(10): nzac105, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36204330

RESUMO

Background: Purified diets (PDs) contain refined ingredients with one main nutrient, allowing for greater control relative to grain-based diets (GBDs), which contain unrefined grains and animal byproducts. Traditional PDs like the American Institute of Nutrition (AIN)-76A (76A) and AIN-93G (93G) can negatively impact metabolic and gut health when fed long term, in part due to lower total fiber, no soluble fiber, and higher sucrose content. Objective: Two studies were conducted to determine how PDs with reduced sucrose and increased fiber (soluble and insoluble) influence metabolic and gut health in mice compared with traditional AIN PDs or GBDs. Methods: In study 1, C57Bl/6N mice (n = 75) consumed a GBD [LabDiet 5002 (5002)], 76A, 93G, or 2 PDs with reduced sucrose and higher fiber for 88 d. Body composition and metabolic parameters were assessed. In study 2, C57Bl/6N mice (n = 54) consumed either 2 GBDs (LabDiet 5001 or 5002) or PDs with different types/levels of fiber for 14 d. Microbiome alterations and predicted functional metagenomic changes were measured. Results: The PD with 75 g cellulose and 25 g inulin per 4084 kcals marginally influenced body weight and adiposity, but improved glucose tolerance relative to 93G (P = 0.0131) and 76A (P = 0.0014). Cecal and colonic weights were lower in mice fed cellulose-based PDs compared with those fed GBDs and soluble-fiber PDs. Soluble-fiber PDs reduced alpha diversity and showed similar beta diversity, which differed from cellulose-based PDs and GBDs. Certain genera associated with improved gut health such as Bifidobacteria and Akkermansia were significantly elevated by soluble-fiber PDs (P ≤ 0.01). Metabolic pathways related to carbohydrate and fatty acid metabolism were affected by PDs. Conclusions: PDs formulated with lower sucrose and increased fiber content, particularly soluble fiber, blunted elevations in metabolic parameters and favorably impacted the microbiota and metagenome in C57BL/6N mice.

14.
Technol Cancer Res Treat ; 21: 15330338221095950, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35466792

RESUMO

Conventional small-molecule drugs (SMDs) are compounds characterized by low molecular weight, high cell permeability, and high selectivity. In clinical translation, SMDs are regarded as good candidates for oral drug formulation. SMD inhibitors play an important role in cancer treatment; however, resistance and low effectiveness have been major bottlenecks in clinical application. Generally, only 20% of cell proteins can potentially be targeted and have been developed as SMDs; thus, some types of tumor targets are considered "undruggable." Among these are transcription factors (TFs), an important class of proteins that regulate the occurrence, formation, and development of tumors. It is difficult for SMDs and macromolecular drugs to identify bioactive sites in TFs and hence for use as pharmacological inhibitors in targeting TF proteins. For this reason, technologies that enable targeted protein degradation, such as proteolysis-targeting chimera or molecular glues, could serve as a potential tool to solve these conundrums.


Assuntos
Neoplasias , Fatores de Transcrição , Descoberta de Drogas , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Proteólise , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
15.
Proteome Sci ; 9(1): 49, 2011 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-21849056

RESUMO

BACKGROUND: We and others have previously reported that resveratrol (RSV) suppresses colon cancer cell proliferation and elevates apoptosis in vitro and/or in vivo, however molecular mechanisms are not fully elucidated. Particularly, little information is available on RSV's effects on metabolic pathways and the cell-extra cellular matrix (ECM) communication that are critical for cancer cell growth. To identify important targets of RSV, we analyzed whole protein fractions from HT-29 advanced human colon cancer cell line treated with solvent control, IGF-1 (10 nM) and RSV (150 µM) using LC/MS/MS-Mud PIT (Multidimensional Protein Identification Technology). RESULTS: Pentose phosphate pathway (PPP), a vital metabolic pathway for cell cycle progression, was elevated and suppressed by IGF-1 and RSV, respectively in the HT-29 cell line. Enzymatic assays confirmed RSV suppression of glucose-6 phosphate dehydrogenase (rate limiting) and transketolase, key enzymes of the PPP. RSV (150 µM) suppressed, whereas IGF-1 (10 nM) elevated focal adhesion complex (FAC) proteins, talin and pFAK, critical for the cell-ECM communication. Western blotting analyses confirmed the suppression or elevation of these proteins in HT-29 cancer cells treated with RSV or IGF-1, respectively. CONCLUSIONS: Proteomic analysis enabled us to establish PPP and the talin-pFAK as targets of RSV which suppress cancer cell proliferation and induce apoptosis in the colon cancer cell line HT-29. RSV (150 µM) suppressed these pathways in the presence and absence of IGF-1, suggesting its role as a chemo-preventive agent even in obese condition.

16.
Curr Dev Nutr ; 5(12): nzab138, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34993389

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is intricately linked to metabolic disease (including obesity, glucose intolerance, and insulin resistance) and encompasses a spectrum of disorders including steatosis, nonalcoholic steatohepatitis (NASH), and fibrosis. Rodents consuming high-fat (HF; ∼40 kcal% fat including fats containing higher concentrations of saturated and trans fats), high-fructose (HFr), and high-cholesterol (HC) diets display many clinically relevant characteristics of NASH, along with other metabolic disorders. C57BL/6 mice are the most commonly used animal model because they can develop significant metabolic disorders including severe NASH with fibrosis after months of feeding, but other models also are susceptible. The significant number of diets that contain these different factors (i.e., HF, HFr, and HC), either alone or in combination, makes the choice of diet difficult. This methodology review describes the efficacy of these nutrient manipulations on the NAFLD phenotype in mice, rats, guinea pigs, hamsters, and nonhuman primates.

17.
BMC Cancer ; 10: 238, 2010 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-20504360

RESUMO

BACKGROUND: Obesity is a global phenomenon and is associated with various types of cancer, including colon cancer. There is a growing interest for safe and effective bioactive compounds that suppress the risk for obesity-promoted colon cancer. Resveratrol (trans-3, 4', 5,-trihydroxystilbene), a stilbenoid found in the skin of red grapes and peanuts suppresses many types of cancers by regulating cell proliferation and apoptosis through a variety of mechanisms, however, resveratrol effects on obesity-promoted colon cancer are not clearly established. METHODS: We investigated the anti-proliferative effects of resveratrol on HT-29 and SW480 human colon cancer cells in the presence and absence of insulin like growth factor-1 (IGF-1; elevated during obesity) and elucidated the mechanisms of action using IGF-1R siRNA in HT-29 cells which represents advanced colon carcinogenesis. RESULTS: Resveratrol (100-150 microM) exhibited anti-proliferative properties in HT-29 cells even after IGF-1 exposure by arresting G0/G1-S phase cell cycle progression through p27 stimulation and cyclin D1 suppression. Treatment with resveratrol suppressed IGF-1R protein levels and concurrently attenuated the downstream Akt/Wnt signaling pathways that play a critical role in cell proliferation. Targeted suppression of IGF-1R using IGF-1R siRNA also affected these signaling pathways in a similar manner. Resveratrol treatment induced apoptosis by activating tumor suppressor p53 protein, whereas IGF-1R siRNA treatment did not affect apoptosis. Our data suggests that resveratrol not only suppresses cell proliferation by inhibiting IGF-1R and its downstream signaling pathways similar to that of IGF-1R siRNA but also enhances apoptosis via activation of the p53 pathway. CONCLUSIONS: For the first time, we report that resveratrol suppresses colon cancer cell proliferation and elevates apoptosis even in the presence of IGF-1 via suppression of IGF-1R/Akt/Wnt signaling pathways and activation of p53, suggesting its potential role as a chemotherapeutic agent.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estilbenos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Proteínas Wnt/metabolismo , Ciclo Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Ciclina D1/metabolismo , Inibidor de Quinase Dependente de Ciclina p27 , Relação Dose-Resposta a Droga , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Células HT29 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Receptor IGF Tipo 1/genética , Resveratrol , Fatores de Tempo
18.
Curr Dev Nutr ; 4(6): nzaa078, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32494762

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is a complex spectrum of disorders ranging from simple benign steatosis to more aggressive forms of nonalcoholic steatohepatitis (NASH) and fibrosis. Although not every patient with NAFLD/NASH develops liver complications, if left untreated it may eventually lead to cirrhosis and hepatocellular carcinoma. Purified diets formulated with specific nutritional components can drive the entire spectrum of NAFLD in rodent models. Although they may not perfectly replicate the clinical and histological features of human NAFLD, they provide a model to gain further understanding of disease progression in humans. Owing to the growing demand of diets for NAFLD research, and for our further understanding of how manipulation of dietary components can alter disease development, we outlined several commonly used dietary approaches for rodent models, including mice, rats, and hamsters, time frames required for disease development and whether other metabolic diseases commonly associated with NAFLD in humans occur.

19.
Nutrition ; 69: 110563, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31622909

RESUMO

Although extensive resources are dedicated to the development and study of cancer drugs, the cancer burden is expected to rise by about 70% over the next 2 decade. This highlights a critical need to develop effective, evidence-based strategies for countering the global rise in cancer incidence. Except in high-risk populations, cancer drugs are not generally suitable for use in cancer prevention owing to potential side effects and substantial monetary costs (Sporn, 2011). There is overwhelming epidemiological and experimental evidence that the dietary bioactive compounds found in whole plant-based foods have significant anticancer and chemopreventative properties. These bioactive compounds often exert pleiotropic effects and act synergistically to simultaneously target multiple pathways of cancer. Common bioactive compounds in fruits and vegetables include carotenoids, glucosinolates, and polyphenols. These compounds have been shown to target multiple hallmarks of cancer in vitro and in vivo and potentially to address the diversity and heterogeneity of certain cancers. Although many studies have been conducted over the past 30 y, the scientific community has still not reached a consensus on exactly how the benefit of bioactive compounds in fruits and vegetables can be best harnessed to help reduce the risk for cancer. Different stages of the food processing system, from "farm-to-fork," can affect the retention of bioactive compounds and thus the chemopreventative properties of whole foods, and there are opportunities to improve handling of foods throughout the stages in order to best retain their chemopreventative properties. Potential target stages include, but are not limited to, pre- and postharvest management, storage, processing, and consumer practices. Therefore, there is a need for a comprehensive food-system-based approach that not only taking into account the effects of the food system on anticancer activity of whole foods, but also exploring solutions for consumers, policymakers, processors, and producers. Improved knowledge about this area of the food system can help us adjust farm-to-fork operations in order to consistently and predictably deliver desired bioactive compounds, thus better utilizing them as invaluable chemopreventative tools in the fight to reduce the growing burden of cancer worldwide.


Assuntos
Dieta Saudável/métodos , Neoplasias/prevenção & controle , Compostos Fitoquímicos/administração & dosagem , Carotenoides/administração & dosagem , Manipulação de Alimentos , Frutas/química , Glucosinolatos/administração & dosagem , Humanos , Polifenóis/administração & dosagem , Verduras/química
20.
Cells ; 9(9)2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32883049

RESUMO

Non-alcoholic steatohepatitis (NASH) is a fast-growing liver disorder that is associated with an increased incidence of cardiovascular disease and type 2 diabetes. Animal models adequately mimicking this condition are scarce. We herein investigate whether Ldlr-/-. Leiden mice on different high-fat diets represent a suitable NASH model. Ldlr-/-. Leiden mice were fed a healthy chow diet or fed a high-fat diet (HFD) containing lard or a fast food diet (FFD) containing milk fat. Additionally, the response to treatment with obeticholic acid (OCA) was evaluated. Both high-fat diets induced obesity, hyperlipidemia, hyperinsulinemia, and increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. Mice on both diets developed progressive macro- and microvesicular steatosis, hepatic inflammation, and fibrosis, along with atherosclerosis. HFD induced more severe hyperinsulinemia, while FFD induced more severe hepatic inflammation with advanced (F3) bridging fibrosis, as well as more severe atherosclerosis. OCA treatment significantly reduced hepatic inflammation and fibrosis, and it did not affect atherosclerosis. Hepatic transcriptome analysis was compared with human NASH and illustrated similarity. The present study defines a translational model of NASH with progressive liver fibrosis and simultaneous atherosclerosis development. By adaptation of the fat content of the diet, either insulin resistance (HFD) or hepatic inflammation and fibrosis (FFD) can be aggravated.


Assuntos
Aterosclerose/sangue , Aterosclerose/etiologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Fast Foods/efeitos adversos , Cirrose Hepática/sangue , Cirrose Hepática/etiologia , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/etiologia , Animais , Aterosclerose/tratamento farmacológico , Aterosclerose/genética , Ácido Quenodesoxicólico/análogos & derivados , Ácido Quenodesoxicólico/uso terapêutico , Hiperinsulinismo/tratamento farmacológico , Hiperinsulinismo/etiologia , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/etiologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Obesidade/sangue , Obesidade/tratamento farmacológico , Obesidade/etiologia , Receptores de LDL/genética , Transcriptoma , Resultado do Tratamento
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