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1.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35027451

RESUMO

The axis of platelet-derived growth factor (PDGF) and PDGF receptor-beta (PDGFRß) plays prominent roles in cell growth and motility. In addition, PDGF-D enhances human natural killer (NK) cell effector functions when binding to the NKp44 receptor. Here, we report an additional but previously unknown role of PDGF-D, whereby it mediates interleukin-15 (IL-15)-induced human NK cell survival but not effector functions via its binding to PDGFRß but independent of its binding to NKp44. Resting NK cells express no PDGFRß and only a low level of PDGF-D, but both are significantly up-regulated by IL-15, via the nuclear factor κB signaling pathway, to promote cell survival in an autocrine manner. Both ectopic and IL-15-induced expression of PDGFRß improves NK cell survival in response to treatment with PDGF-D. Our results suggest that the PDGF-D-PDGFRß signaling pathway is a mechanism by which IL-15 selectively regulates the survival of human NK cells without modulating their effector functions.


Assuntos
Interleucina-15/metabolismo , Células Matadoras Naturais/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais/fisiologia , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Linfocinas , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Receptor 2 Desencadeador da Citotoxicidade Natural , Fator de Crescimento Derivado de Plaquetas/farmacologia , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética
2.
J Virol ; 96(1): e0096421, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34668775

RESUMO

A comprehensive analysis and characterization of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection model that mimics non-severe and severe coronavirus disease 2019 (COVID-19) in humans is warranted for understating the virus and developing preventive and therapeutic agents. Here, we characterized the K18-hACE2 mouse model expressing human (h)ACE2 in mice, controlled by the human keratin 18 (K18) promoter, in the epithelia, including airway epithelial cells where SARS-CoV-2 infections typically start. We found that intranasal inoculation with higher viral doses (2 × 103 and 2 × 104 PFU) of SARS-CoV-2 caused lethality of all mice and severe damage of various organs, including lung, liver, and kidney, while lower doses (2 × 101 and 2 × 102 PFU) led to less severe tissue damage and some mice recovered from the infection. In this hACE2 mouse model, SARS-CoV-2 infection damaged multiple tissues, with a dose-dependent effect in most tissues. Similar damage was observed in postmortem samples from COVID-19 patients. Finally, the mice that recovered from infection with a low dose of virus survived rechallenge with a high dose of virus. Compared to other existing models, the K18-hACE2 model seems to be the most sensitive COVID-19 model reported to date. Our work expands the information available about this model to include analysis of multiple infectious doses and various tissues with comparison to human postmortem samples from COVID-19 patients. In conclusion, the K18-hACE2 mouse model recapitulates both severe and non-severe COVID-19 in humans being dose-dependent and can provide insight into disease progression and the efficacy of therapeutics for preventing or treating COVID-19. IMPORTANCE The pandemic of coronavirus disease 2019 (COVID-19) has reached nearly 240 million cases, caused nearly 5 million deaths worldwide as of October 2021, and has raised an urgent need for the development of novel drugs and therapeutics to prevent the spread and pathogenesis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To achieve this goal, an animal model that recapitulates the features of human COVID-19 disease progress and pathogenesis is greatly needed. In this study, we have comprehensively characterized a mouse model of SARS-CoV-2 infection using K18-hACE2 transgenic mice. We infected the mice with low and high doses of SARS-CoV-2 to study the pathogenesis and survival in response to different infection patterns. Moreover, we compared the pathogenesis of the K18-hACE2 transgenic mice with that of the COVID-19 patients to show that this model could be a useful tool for the development of antiviral drugs and therapeutics.


Assuntos
COVID-19/patologia , Modelos Animais de Doenças , SARS-CoV-2/patogenicidade , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , COVID-19/imunologia , COVID-19/mortalidade , COVID-19/virologia , Humanos , Soros Imunes/imunologia , Queratina-18/genética , Camundongos , Camundongos Transgênicos , Regiões Promotoras Genéticas , Reinfecção/imunologia , Reinfecção/mortalidade , Reinfecção/patologia , Reinfecção/virologia , SARS-CoV-2/imunologia , Proteínas Virais/genética , Proteínas Virais/metabolismo
3.
Crit Rev Food Sci Nutr ; : 1-23, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38063335

RESUMO

For years, researchers have been tirelessly searching for efficient postharvest preservatives to ensure a sustainable and healthy supply chain of fresh fruits and vegetables. However, the effectiveness of preservatives is significantly influenced by delivery methods employed for preservatives. This work centers on delivery methods of diverse preservatives. It delves into the mechanisms of penetration and internalization that facilitate preservatives diffusion into fruits and vegetables. Furthermore, the study comprehensively reviews various delivery methods and their impact on postharvest quality of these fresh food. Methods include liquid surface impregnation (soaking, vacuum infiltration, spraying) and gaseous fumigation. Additionally, unconventional delivery measures, such as fruit stem delivery, microbubble, and edible coating, are discussed in detail for the first time. It is expected that our work will provide inspiration for future development in academia, industry, and supervision.Through a comprehensive review on preservative delivery methods in fruits and vegetables preservation, it becomes evident that majority of existing studies concentrate on the development and mechanisms of preservatives. However, a notable gap lies in comparative analysis of different delivery methods, despite the direct impact of delivery methods on preservation outcomes. Additionally, emerging delivery techniques have displayed promising potential in enhancing delivery efficiency and likewise preservation effectiveness.


Preservative delivery methods (soaking, vacuum infiltration, spraying, fumigation) directly impact their effectiveness.Delivery efficiency is linked to fruit epidermis, including cuticle, intercellular spaces, and stomata.Research uses varied delivery methods, concentrations, and times for preserving different fruits.Promising preservative delivery methods: microbubble, fruit stem delivery, and edible coating.

4.
Semin Cancer Biol ; 73: 331-346, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33794344

RESUMO

Dietary interventions are key nutritional strategies to prevent, improve, and prolong the survival of cancer patients. Lycopene, one of the strongest natural antioxidants, and its biologically active metabolites, have shown significant potential to prevent a variety of cancers, including prostate, breast, and stomach cancers, making it a promising anti-cancer agent. We review the potential regulatory mechanisms and epidemiological evidences of lycopene and its metabolites to delay the progression of cancers at different developmental stages. Recent studies have revealed that lycopene and its metabolites mediate multiple molecular mechanisms in cancer treatment such as redox homeostasis, selective anti-proliferation, apoptosis, anti-angiogenesis, tumour microenvironment regulation, and anti-metastasis and anti-invasion. Gut microbes and cholesterol metabolism are also the potential regulation targets of lycopene and its metabolites. As a dietary supplement, the synergistic interaction of lycopene with other drugs and nutrients is highlighted especially due to its binding activity with other nutrients in the diet found central to the fight against cancer. Furthermore, the application of several of novel lycopene delivery carriers are on the rise including nanoemulsions, nanostructured liposomes, and polymer nanoparticles for cancer prevention as discussed in this review with future needed development. Moreover, the synergistic mechanism between lycopene and other nutrients or drugs and novel delivery systems of lycopene should now be deeply investigated to improve its clinical application in cancer intervention in the future.


Assuntos
Anticarcinógenos , Licopeno , Neoplasias , Animais , Sistemas de Liberação de Medicamentos , Humanos
5.
Crit Rev Food Sci Nutr ; : 1-20, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36123797

RESUMO

During the COVID-19 pandemic, the botanical product market saw a consumer interest increase in immune health supplements. While data are currently insufficient to support public health guidance for using foods and dietary supplements to prevent or treat COVID-19 and other immune disorders, consumer surveys indicate that immune support is the second-most cited reason for supplement use in the United States. Meanwhile, consumers showed increased attention to dietary supplement ingredient labels, especially concerning authenticity and ingredient claims. Top-selling botanical ingredients such as elderberry, turmeric, and functional mushrooms have been increasingly marketed toward consumers to promote immune health, but these popular products succumb to adulteration with inaccurate labeling due to the intentional or unintentional addition of lower grade ingredients, non-target plants, and synthetic compounds, partially due to pandemic-related supply chain issues. This review highlights the regulatory requirements and recommendations for analytical approaches, including chromatography, spectroscopy, and DNA approaches for ingredient claim verification. Demonstrating elderberry, turmeric, and functional mushrooms as examples, this review aims to provide industrial professionals and scientists an overview of current United States regulations, testing approaches, and trends for label compliance verification to ensure the safety of botanical products marketed for "immune health."

6.
Compr Rev Food Sci Food Saf ; 20(1): 627-651, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33325130

RESUMO

Recently, interests in binary protein systems have been developed considerably ascribed to the sustainability, environment-friendly, rich in nutrition, low cost, and tunable mechanical properties of these systems. However, the molecular coalition is challenged by the complex mechanisms of interaction, aggregation, gelation, and emulsifying of the mixed system in which another protein is introduced. To overcome these fundamental difficulties and better modulate the structural and functional properties of binary systems, efforts have been steered to gain basic information regarding the underlying dynamics, theories, and physicochemical characteristics of mixed systems. Therefore, the present review provides an overview of the current studies on the behaviors of proteins in such systems and highlights shortcomings and future challenges when applied in scientific fields.


Assuntos
Alimentos , Proteínas
7.
Chem Biodivers ; 17(2): e1900040, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31815342

RESUMO

A new indole derivative colletoindole A (1), along with two new indole derivatives (2 and 3) and one known compound acropyrone (4) were isolated from cultures of Colletotrichum tropicale SCSIO 41022 derived from a mangrove plant Kandelia candel. The structures of 1-4 were determined by analysis of NMR and MS data. The cytotoxicity of 1, 2 and 4, and the COX-2 inhibitory activity of 1 and 2 were evaluated.


Assuntos
Colletotrichum/química , Indóis/química , Rhizophoraceae/microbiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Colletotrichum/classificação , Colletotrichum/metabolismo , Humanos , Indóis/isolamento & purificação , Indóis/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Filogenia
8.
Int J Neurosci ; 130(8): 826-833, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31858860

RESUMO

Purpose: Wernekink commissure syndrome is a typical but extremely rare mesencephalic syndrome, and generally presents with bilateral cerebellar dysfunction, diverse oculomotor disorders and occasionally delayed-onset palatal myoclonus or tremor. However, it has been reported infrequently.Methods: We report a case of a 55-year-old man who suffered an acute paramedian midbrain infarction presenting with bilateral cerebellar ataxia, bilateral anterior internuclear ophthalmoplegia and unilateral pseudoabducens palsy, which is confirmed as Wernekink commissure syndrome by magnetic resonance imaging (MRI). We summarized the clinical data of this entity and performed a literature review of 20 previous reports of patients with this syndrome.Results: In combination with previous reports, we found that the most common symptom was bilateral cerebellar ataxia (100%) and other frequent symptoms were oculomotor disorders (81%), delayed palatal myoclonus or tremor (33%) and consciousness dysfunction (33%). Lesions on brain MRI of all patients affected the area of caudal paramedian midbrain (CPM).Conclusion: Bilateral cerebellar ataxia and lesions involved in the area of CPM on MRI are the major features of Wernekink commissure syndrome and should be the necessary conditions of diagnostic criteria. The simultaneous occurrence of bilateral cerebellar ataxia and oculomotor disorders is significant for localization diagnosis. Consciousness dysfunction is also a relatively frequent symptom of this syndrome. Moreover, pseudoabducens palsy might be attributed to a midbrain lesion. Clinicians should be familiar with and early to recognize this unique syndrome to avoid misdiagnosis.


Assuntos
Doenças do Nervo Abducente , Infarto Encefálico , Ataxia Cerebelar , Mesencéfalo/patologia , Oftalmoplegia , Doenças do Nervo Abducente/etiologia , Doenças do Nervo Abducente/fisiopatologia , Infarto Encefálico/complicações , Infarto Encefálico/patologia , Infarto Encefálico/fisiopatologia , Ataxia Cerebelar/etiologia , Ataxia Cerebelar/fisiopatologia , Transtornos da Consciência/etiologia , Transtornos da Consciência/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Mesencéfalo/diagnóstico por imagem , Pessoa de Meia-Idade , Mioclonia/etiologia , Mioclonia/fisiopatologia , Oftalmoplegia/etiologia , Oftalmoplegia/fisiopatologia , Síndrome , Tremor/etiologia , Tremor/fisiopatologia
9.
Curr Opin Gastroenterol ; 35(2): 101-106, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30550380

RESUMO

PURPOSE OF REVIEW: Colorectal cancer (CRC) is one of the most common cancers and the fourth leading cause of cancer-related deaths worldwide. Diet has a significant impact on the risk of developing CRC, but though processed meat is a known positive contributor, the effects of other dietary components are largely mixed. This review focuses on dietary patterns to describe the complexity of dietary diversity and overall food consumption and to examine the relationship between dietary patterns and risk of CRC. RECENT FINDINGS: After searching human studies published in 2017-2018, we selected and evaluated 30 articles, including meta-analyses, cohort studies, and prospective studies. These studies suggest that the prudent or Mediterranean dietary pattern significantly decreases the risk of CRC compared to the Western dietary pattern; a lower dietary inflammatory index or a higher dietary quality index associates with a lower risk of CRC; closely following all aspects of the World Cancer Research Fund/American Institute for Cancer Research cancer prevention guidelines and recommendations correlates with a reduced risk of CRC. SUMMARY: The risk of developing CRC can be reduced by adopting a healthier lifestyle. More studies of the impact of diet on clinical outcomes of CRC are needed.


Assuntos
Neoplasias Colorretais/etiologia , Dieta , Animais , Comportamento Alimentar , Humanos , Política Nutricional
10.
Crit Rev Food Sci Nutr ; 59(6): 992-1007, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30795687

RESUMO

Cancer is considered a fetal disease caused by uncontrolled proliferation and progression of abnormal cells. The most efficient cancer therapies suppress tumor growth, prevent progression and metastasis, and are minimally toxic to normal cells. Natural compounds have shown a variety of chemo-protective effects alone or in combination with standard cancer therapies. Along with better understanding of the dynamic interactions between our immune system and cancer development, nutritional immunology-the use of natural compounds as immunomodulators in cancer patients-has begun to emerge. Cancer cells evolve strategies that target many aspects of the immune system to escape or even edit immune surveillance. Therefore, the immunesuppressive tumor microenvironment is a major obstacle in the development of cancer therapies. Because interaction between the tumor microenvironment and the immune system is a complex topic, this review focuses mainly on human clinical trials and animal studies, and it highlights specific immune cells and their cytokines that have been modulated by natural compounds, including carotenoids, curcumin, resveratrol, EGCG, and ß-glucans. These natural compounds have shown promising immune-modulating effects, such as inhibiting myeloid-derived suppressor cells and enhancing natural killer and cytolytic T cells, in tumor-bearing animal models, but their efficacy in cancer patients remains to be determined.


Assuntos
Fatores Imunológicos/imunologia , Fatores Imunológicos/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Animais , Carotenoides/farmacologia , Catequina/análogos & derivados , Catequina/farmacologia , Curcumina/farmacologia , Humanos , Sistema Imunitário , Células Matadoras Naturais/efeitos dos fármacos , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Resveratrol/farmacologia , Linfócitos T/efeitos dos fármacos , Tretinoína/farmacologia , beta-Glucanas/farmacologia
11.
Lab Invest ; 98(11): 1397-1407, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29955087

RESUMO

Endometrial cancer is the most common gynecological cancer in the United States. We wanted to identify epigenetic aberrations involving microRNAs (miRNAs), whose genes become hypermethylated in endometrial primary tumors. By integrating known miRNA sequences from the miRNA database (miRBase) with DNA methylation data from methyl-CpG-capture sequencing, we identified 111 differentially methylated regions (DMRs) associated with CpG islands (CGIs) and miRNAs. Among them, 22 DMRs related to 29 miRNAs and within 8 kb of CGIs were hypermethylated in endometrial tumors but not in normal endometrium. miR-137 was further validated in additional endometrial primary tumors. Hypermethylation of miR-137 was found in both endometrioid and serous endometrial cancer (P < 0.01), and it led to the loss of miR-137 expression. Treating hypermethylated endometrial cancer cells with epigenetic inhibitors reactivated miR-137. Moreover, genetic overexpression of miR-137 suppressed cancer cell proliferation and colony formation in vitro. When transfected cancer cells were implanted into nude mice, the cells that overexpressed miR-137 grew more slowly and formed smaller tumors (P < 0.05) than vector transfectants. Histologically, xenograft tumors from cancer cells expressing miR-137 were less proliferative (P < 0.05), partly due to inhibition of EZH2 and LSD1 expression (P < 0.01) in both the transfected cancer cells and tumors. Reporter assays indicated that miR-137 targets EZH2 and LSD1. These results suggest that miR-137 is a tumor suppressor that is repressed in endometrial cancer because the promoter of its gene becomes hypermethylated.


Assuntos
Adenocarcinoma/metabolismo , Metilação de DNA , Neoplasias do Endométrio/metabolismo , Inativação Gênica , MicroRNAs/metabolismo , Adenocarcinoma/genética , Animais , Linhagem Celular Tumoral , Neoplasias do Endométrio/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Feminino , Histona Desmetilases/metabolismo , Humanos , Camundongos Nus , MicroRNAs/genética
12.
Int J Cancer ; 143(4): 886-896, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-29524208

RESUMO

Free fatty acid receptor 2 (FFAR2, also named GPR43), is activated by short-chain fatty acids (SCFAs), such as butyrate, that are produced when gut bacteria ferment dietary fiber. FFAR2 has been suggested to regulate colonic inflammation, which is a major risk factor for the development of colon cancer and is also linked to epigenetic dysregulation in colon carcinogenesis. The current study assessed whether FFAR2, acting as an epigenetic regulator, protects against colon carcinogenesis. To mimic the mild inflammation that promotes human colon cancer, we treated mice with dextran sodium sulfate (DSS) overnight, which avoids excessive inflammation but induces mild inflammation that promotes colon carcinogenesis in the ApcMin/+ and the azoxymethane (AOM)-treated mice. Our results showed that FFAR2 deficiency promotes the development of colon adenoma in the ApcMin/+ /DSS mice and the progression of adenoma to adenocarcinoma in the AOM/DSS mice. FFAR2's downstream cAMP-PKA-CREB pathway was enhanced, leading to overexpression of histone deacetylases (HDACs) in the FFAR2-deficient mice. ChIP-qPCR analysis revealed differential binding of H3K27me3 and H3K4me3 histone marks onto the promoter regions of inflammation suppressors (e.g., sfrp1, dkk3, socs1), resulting in decreased expression of these genes in the FFAR2-deficient mice. Also, more neutrophils infiltrated into tumors and colon lamina propria of the FFAR2-deficient mice. Depletion of neutrophils blocked the progression of colon tumors. In addition, FFAR2 is required for butyrate to suppress HDAC expression and hypermethylation of inflammation suppressors. Therefore, our results suggest that FFAR2 is an epigenetic tumor suppressor that acts at multiple stages of colon carcinogenesis.


Assuntos
Colite/genética , Neoplasias do Colo/genética , Epigênese Genética , Inflamação/genética , Inflamação/prevenção & controle , Neoplasias Experimentais/genética , Receptores Acoplados a Proteínas G/genética , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/genética , Adenoma/induzido quimicamente , Adenoma/genética , Adenoma/patologia , Animais , Azoximetano/administração & dosagem , Colite/induzido quimicamente , Neoplasias do Colo/induzido quimicamente , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Sulfato de Dextrana , Progressão da Doença , Histona Desacetilases/metabolismo , Homeostase , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias Experimentais/induzido quimicamente , Neutrófilos/metabolismo
13.
Int J Mol Sci ; 19(1)2018 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-29316620

RESUMO

Early inhibition of inflammation suppresses the carcinogenic process. Aspirin is the most commonly used non-steroid anti-inflammatory drugs (NSAIDs), and it irreversibly inhibits cyclooxygenase-1 and -2 (COX1, COX2). Multiple randomized clinical trials have demonstrated that aspirin offers substantial protection from colon cancer mortality. The lower aspirin doses causing only minimal gastrointestinal disturbance, ideal for long-term use, can achieve only partial and transitory inhibition of COX2. Aspirin's principal metabolite, salicylic acid, is also found in fruits and vegetables that inhibit COX2. Other phytochemicals such as curcumin, resveratrol, and anthocyanins also inhibit COX2. Such dietary components are good candidates for combination with aspirin because they have little or no toxicity. However, obstacles to using phytochemicals for chemoprevention, including bioavailability and translational potential, must be resolved. The bell/U-shaped dose-response curves seen with vitamin D and resveratrol might apply to other phytochemicals, shedding doubt on 'more is better'. Solutions include: (1) using special delivery systems (e.g., nanoparticles) to retain phytochemicals; (2) developing robust pharmacodynamic biomarkers to determine efficacy in humans; and (3) selecting pharmacokinetic doses relevant to humans when performing preclinical experiments. The combination of aspirin and phytochemicals is an attractive low-cost and low-toxicity approach to colon cancer prevention that warrants testing, particularly in high-risk individuals.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Aspirina/uso terapêutico , Neoplasias do Colo/prevenção & controle , Fibras na Dieta/uso terapêutico , Quimioprevenção , Ensaios Clínicos como Assunto , Neoplasias do Colo/patologia , Sinergismo Farmacológico , Humanos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/uso terapêutico , Prostaglandina-Endoperóxido Sintases/química , Prostaglandina-Endoperóxido Sintases/metabolismo
14.
Carcinogenesis ; 38(1): 86-93, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27866157

RESUMO

We previously showed that black raspberries (BRBs) have beneficial effects in human colorectal cancer and a mouse model of colorectal cancer (ApcMin/+). The current study investigated the role of free fatty acid receptor 2 (FFAR2) in colon carcinogenesis and whether the FFAR2 signaling pathway contributes to BRB-mediated chemoprevention in mice. FFAR2 (also named GPR43) is a member of the G-protein-coupled receptor family that is expressed in leukocytes and colon. ApcMin/+ and ApcMin/+-FFAR2-/- mice were given a control diet or the control diet supplemented with 5% BRBs for 8 weeks. FFAR2 deficiency promoted colonic polyp development, with 100% incidence and increased polyp number and size. The ApcMin/+ mice developed colonic tubular adenoma, whereas the ApcMin/+-FFAR2-/- mice developed colonic tubular adenoma with high-grade dysplasia. FFAR2 deficiency also enhanced the cAMP-PKA-CREB-HDAC pathway, downstream of FFAR2 signaling, and increased activation of the Wnt pathway, and raised the percentage of GR-1+ neutrophils in colonic lamina propria (LP) and increased infiltration of GR-1+ neutrophils into colonic polyps. BRBs suppressed colonic polyp development and inhibited the cAMP-PKA-CREB-HDAC and Wnt pathways in the ApcMin/+ mice but not the ApcMin/+-FFAR2-/- mice. They also increased the percentage of GR-1+ neutrophils and cytokine secretion in colonic LP and decreased the infiltration of GR-1+ neutrophils and IL-1ß expression in colon polyps of ApcMin/+ mice but not ApcMin/+-FFAR2-/- mice. These results suggest that loss of FFAR2 drives colon tumorigenesis and that BRBs require functional FFAR2 to be chemopreventive. BRBs have the potential to modulate the host immune system, thereby enhancing the antitumor immune microenvironment.


Assuntos
Adenoma/patologia , Anticarcinógenos/farmacologia , Colo/patologia , Neoplasias do Colo/patologia , Genes APC/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Rubus/química , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenoma/tratamento farmacológico , Adenoma/metabolismo , Animais , Carcinogênese , Colo/efeitos dos fármacos , Colo/metabolismo , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Modelos Animais de Doenças , Feminino , Frutas/química , Humanos , Masculino , Camundongos , Extratos Vegetais/farmacologia
15.
Nutr Cancer ; 69(6): 943-951, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28718724

RESUMO

Natural compounds can alter the diversity and composition of the gut microbiome, potentially benefiting our health. We previously demonstrated chemopreventive effects of black raspberries (BRBs) in colorectal cancer, which is associated with gut dysbiosis. To investigate the effects of whole BRBs and their fractions on gut microbiota, we fed F-344 rats a control diet, 5% BRBs, the BRB anthocyanin fraction, or the BRB residue fraction for 6 weeks. Feces were collected at baseline and at weeks 3 and 6, and bacterial sequence counts were analyzed. We observed distinct patterns of microbiota from different diet groups. Beta diversity analysis suggested that all diet groups exerted time-dependent changes in the bacterial diversity. Hierarchical clustering analysis revealed that post-diet fecal microbiota was segregated from baseline fecal microbiota within each diet. It is interesting to note that fractions of BRBs induced different changes in gut bacteria compared to whole BRBs. The abundance of specific microbial species known to have anti-inflammatory effects, such as Akkermansia and Desulfovibrio, was increased by whole BRBs and their residue. Further, butyrate-producing bacteria, e.g., Anaerostipes, were increased by whole BRBs. Our results suggest that whole BRBs and their fractions alter the gut microbiota in ways that could significantly influence human health.


Assuntos
Antocianinas/farmacologia , Fibras na Dieta/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Rubus/química , Animais , Antocianinas/análise , Clostridiales/efeitos dos fármacos , Clostridiales/isolamento & purificação , Desulfovibrio/efeitos dos fármacos , Desulfovibrio/isolamento & purificação , Dieta , Fibras na Dieta/análise , Fezes/microbiologia , Frutas/química , Ratos , Ratos Endogâmicos F344 , Verrucomicrobia/efeitos dos fármacos , Verrucomicrobia/isolamento & purificação
16.
Nutr Cancer ; 69(2): 299-306, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28094560

RESUMO

INTRODUCTION: Freeze-dried black raspberries (BRBs) elicit chemopreventive effects against colorectal cancer in humans and in rodents. The objective of this study was to investigate potential BRB-caused metabolite changes using wild-type (WT) C57BL/6 mice. METHODS AND RESULTS: WT mice were fed either control diet or control diet supplemented with 5% BRBs for 8 wk. A nontargeted metabolomic analysis was conducted on colonic mucosa, liver, and fecal specimens collected from both diet groups. BRBs significantly changed the levels of 41 colonic mucosa metabolites, 40 liver metabolites, and 34 fecal metabolites compared to control diet-fed mice. BRBs reduced 34 lipid metabolites in colonic mucosa and increased levels of amino acids in liver. One metabolite, 3-[3-(sulfooxy) phenyl] propanoic acid, might be a useful biomarker of BRB consumption. In addition, BRB powder was found to contain 30-fold higher levels of linolenate compared to control diets. Consistently, multiple omega-3 polyunsaturated fatty acids (ω-3 PUFAs), including stearidonate, docosapentaenoate (ω-3 DPA), eicosapentaenoate (EPA), and docosahexaenoate (DHA), were significantly elevated in livers of BRB-fed mice. CONCLUSION: The data from the current study suggest that BRBs produce systemic metabolite changes in multiple tissue matrices, supporting our hypothesis that BRBs may serve as both a chemopreventive agent and a beneficial dietary supplement.


Assuntos
Aminoácidos/metabolismo , Anticarcinógenos/farmacologia , Colo/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Rubus , Animais , Benzoatos/metabolismo , Suplementos Nutricionais , Ácidos Graxos Ômega-3/metabolismo , Fezes , Mucosa Intestinal/metabolismo , Camundongos Endogâmicos C57BL
17.
Mol Carcinog ; 55(11): 1867-1875, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27696538

RESUMO

Aberrant methylation of DNA is a common event in the development of cancers, including squamous cell carcinoma (SCC) of the human esophagus. In the present study, we determined: (a) whether aberrant DNA methylation also occurs in the development of N-nitrosomethylbenzylamine (NMBA)-induced tumorigenesis in the rat esophagus, a model of human esophageal SCC; and (b) if so, whether dietary black raspberries (BRBs) are capable of preventing this aberrant DNA methylation. A diet containing 5% BRBs inhibited the development of NMBA-induced tumors in the rat esophagus. This inhibition was associated with reduced mRNA levels of the DNA methyltransferases, Dnmt1 and Dnmt3b, in both dysplastic lesions and in papillomas of the esophagus. In addition, promoter methylation of Sfrp4, a WNT pathway antagonist, was significantly reduced by the berry diet, and this was associated with decreased nuclear localization of ß-CATENIN and reduced expression of c-MYC protein in NMBA-treated esophagi. Decreased promoter methylation of Sfrp4 correlated with decreased expression of Dmnt3b and, ultimately, with increased Sfrp4 mRNA expression. This suggests that epigenetic alterations in NMBA-induced rat esophageal tumorigenesis recapitulate epigenetic events in human esophageal SCC, and that BRBs could be useful in preventing the aberrant DNA methylation involved in the development of human esophageal SCC. © 2015 Wiley Periodicals, Inc.


Assuntos
Carcinoma de Células Escamosas/dietoterapia , DNA (Citosina-5-)-Metiltransferases/genética , Dimetilnitrosamina/análogos & derivados , Neoplasias Esofágicas/dietoterapia , Extratos Vegetais/administração & dosagem , Proteínas Proto-Oncogênicas/genética , Rubus/química , Animais , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/genética , DNA (Citosina-5-)-Metiltransferase 1 , Metilação de DNA/efeitos dos fármacos , Dimetilnitrosamina/efeitos adversos , Epigênese Genética/efeitos dos fármacos , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Extratos Vegetais/farmacologia , Ratos , Via de Sinalização Wnt/efeitos dos fármacos , DNA Metiltransferase 3B
18.
J Immunol ; 193(6): 2994-3002, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25122922

RESUMO

Natural products are a major source for cancer drug development. NK cells are a critical component of innate immunity with the capacity to destroy cancer cells, cancer-initiating cells, and clear viral infections. However, few reports describe a natural product that stimulates NK cell IFN-γ production and unravel a mechanism of action. In this study, through screening, we found that a natural product, phyllanthusmin C (PL-C), alone enhanced IFN-γ production by human NK cells. PL-C also synergized with IL-12, even at the low cytokine concentration of 0.1 ng/ml, and stimulated IFN-γ production in both human CD56(bright) and CD56(dim) NK cell subsets. Mechanistically, TLR1 and/or TLR6 mediated PL-C's activation of the NF-κB p65 subunit that in turn bound to the proximal promoter of IFNG and subsequently resulted in increased IFN-γ production in NK cells. However, IL-12 and IL-15Rs and their related STAT signaling pathways were not responsible for the enhanced IFN-γ secretion by PL-C. PL-C induced little or no T cell IFN-γ production or NK cell cytotoxicity. Collectively, we identify a natural product with the capacity to selectively enhance human NK cell IFN-γ production. Given the role of IFN-γ in immune surveillance, additional studies to understand the role of this natural product in prevention of cancer or infection in select populations are warranted.


Assuntos
Benzodioxóis/farmacologia , Glicosídeos/farmacologia , Interferon gama/biossíntese , Células Matadoras Naturais/imunologia , Fator de Transcrição RelA/imunologia , Antígeno CD56/biossíntese , Antígeno CD56/genética , Células Cultivadas , Células HEK293 , Humanos , Interleucina-12/farmacologia , Interleucina-15/farmacologia , Ativação Linfocitária/imunologia , Interferência de RNA , RNA Interferente Pequeno , Receptores de Interleucina-15 , Transdução de Sinais/imunologia , Receptor 1 Toll-Like/genética , Receptor 1 Toll-Like/imunologia , Receptor 6 Toll-Like/imunologia , Fator de Transcrição RelA/biossíntese , Regulação para Cima
19.
Carcinogenesis ; 36(10): 1245-53, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26246425

RESUMO

Freeze-dried black raspberries (BRBs) have demonstrated chemopreventive effects in a dietary intervention trial with human colorectal cancer patients. The aim of this study was to investigate BRB-caused metabolite changes using the Apc(Min/+) mouse as a model of human colorectal cancer. Wild-type (WT) mice were fed control diet, and Apc(Min/+) mice were fed either control diet or control diet supplemented with 5% BRBs for 8 weeks. Colonic and intestinal polyp size and number were measured. A non-targeted metabolomic analysis was conducted on colonic mucosa, liver and fecal specimens. Eight weeks of BRB treatment significantly decreased intestinal and colonic polyp number and size in Apc(Min/+) mice. The apc gene mutation significantly changed 52 metabolites in colonic mucosa associated with increased amino acid and decreased lipid metabolites, as well as 39 liver and 8 fecal metabolites. BRBs significantly reversed 23 apc-regulated metabolites, including 13 colonic mucosa, 8 liver and 2 fecal metabolites that were involved in amino acid, glutathione, lipid and nucleotide metabolism. Of these, changes in eight metabolites were linearly correlated with decreased colonic polyp number and size in BRB-treated Apc(Min/+) mice. Elevated levels of putrescine and linolenate in Apc(Min/+) mice were significantly decreased by BRBs. Ornithine decarboxylase expression, the key enzyme in putrescine generation, was fully suppressed by BRBs. These results suggest that BRBs produced beneficial effects against colonic adenoma development in Apc(Min/+) mice and modulated multiple metabolic pathways. The metabolite changes produced by BRBs might potentially reflect the BRB-mediated chemopreventive effects in colorectal cancer patients.


Assuntos
Adenoma/dietoterapia , Proteína da Polipose Adenomatosa do Colo/genética , Neoplasias Colorretais/dietoterapia , Frutas , Rubus , Adenoma/metabolismo , Adenoma/patologia , Animais , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Mucosa Intestinal/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Putrescina/biossíntese , Ácido alfa-Linolênico/biossíntese
20.
Mar Drugs ; 13(1): 237-48, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25574738

RESUMO

Four new meroterpenoids (2-5), along with three known analogues (1, 6, and 7) were isolated from mangrove plant Acanthus ilicifolius derived endophytic fungus Aspergillus flavipes. The structures of these compounds were elucidated by NMR and MS analysis, the configurations were assigned by CD data, and the stereochemistry of 1 was confirmed by X-ray crystallography analysis. A possible biogenetic pathway of compounds 1-7 was also proposed. All compounds were evaluated for antibacterial and cytotoxic activities.


Assuntos
Acanthaceae/microbiologia , Aspergillus/química , Terpenos/isolamento & purificação , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Terpenos/química , Terpenos/metabolismo , Áreas Alagadas
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