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1.
Adv Sci (Weinh) ; : e2306890, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816931

RESUMO

In spite of recent advances in the field of undernutrition, current dietary therapy relying on the supply of high protein high calorie formulas is still plagued with transient recovery of impaired organs resulting in significant relapse of cases. This is partly attributed to the inadequacy of current research models in recapitulating clinical undernutrition for mechanistic exploration. Using 1636 Macaca fascicularis monkeys, a human-relevant criterion for determining undernutrition weight-for-age z-score (WAZ), with a cutoff point of ≤ -1.83 is established as the benchmark for identifying undernourished nonhuman primates (U-NHPs). In U-NHPs, pathological anomalies in multi-organs are revealed. In particular, severe dysregulation of hepatic lipid metabolism characterized by impaired fatty acid oxidation due to mitochondria dysfunction, but unlikely peroxisome disorder, is identified as the anchor metabolic aberration in U-NHPs. Mitochondria dysfunction is typified by reduced mito-number, accumulated long-chain fatty acids, and disruption of OXPHOS complexes. Soy peptide-treated U-NHPs increase in WAZ scores, in addition to attenuated mitochondria dysfunction and restored OXPHOS complex levels. Herein, innovative criteria for identifying U-NHPs are developed, and unknown molecular mechanisms of undernutrition are revealed hitherto, and it is further proved that soypeptide supplementation reprogramed mitochondrial function to re-establish lipid metabolism balance and mitigated undernutrition.

2.
Cancer Immunol Immunother ; 73(7): 128, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743074

RESUMO

The majority of the immune cell population in the tumor microenvironment (TME) consists of tumor-associated macrophages (TAM), which are the main players in coordinating tumor-associated inflammation. TAM has a high plasticity and is divided into two main phenotypes, pro-inflammatory M1 type and anti-inflammatory M2 type, with tumor-suppressive and tumor-promoting functions, respectively. Considering the beneficial effects of M1 macrophages for anti-tumor and the high plasticity of macrophages, the conversion of M2 TAM to M1 TAM is feasible and positive for tumor treatment. This study sought to evaluate whether the glycopeptide derived from simulated digested Codonopsis pilosula extracts could regulate the polarization of M2-like TAM toward the M1 phenotype and the potential regulatory mechanisms. The results showed that after glycopeptide dCP1 treatment, the mRNA relative expression levels of some M2 phenotype marker genes in M2-like TAM in simulated TME were reduced, and the relative expression levels of M1 phenotype marker genes and inflammatory factor genes were increased. Analysis of RNA-Seq of M2-like TAM after glycopeptide dCP1 intervention showed that the gene sets such as glycolysis, which is associated with macrophage polarization in the M1 phenotype, were significantly up-regulated, whereas those of gene sets such as IL-6-JAK-STAT3 pathway, which is associated with polarization in the M2 phenotype, were significantly down-regulated. Moreover, PCA analysis and Pearson's correlation also indicated that M2-like TAM polarized toward the M1 phenotype at the transcriptional level after treatment with the glycopeptide dCP1. Lipid metabolomics was used to further explore the efficacy of the glycopeptide dCP1 in regulating the polarization of M2-like TAM to the M1 phenotype. It was found that the lipid metabolite profiles in dCP1-treated M2-like TAM showed M1 phenotype macrophage lipid metabolism profiles compared with blank M2-like TAM. Analysis of the key differential lipid metabolites revealed that the interconversion between phosphatidylcholine (PC) and diacylglycerol (DG) metabolites may be the central reaction of the glycopeptide dCP1 in regulating the conversion of M2-like TAM to the M1 phenotype. The above results suggest that the glycopeptide dCP1 has the efficacy to regulate the polarization of M2-like TAM to M1 phenotype in simulated TME.


Assuntos
Codonopsis , Fenótipo , Microambiente Tumoral , Macrófagos Associados a Tumor , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/efeitos dos fármacos , Animais , Camundongos , Microambiente Tumoral/efeitos dos fármacos , Humanos , Glicopeptídeos/metabolismo , Glicopeptídeos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/imunologia
3.
Cancer Pathog Ther ; 2(1): 15-23, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38328712

RESUMO

Brain metastases are a leading cause of cancer-related mortality. However, progress in their treatment has been limited over the past decade, due to an incomplete understanding of the underlying biological mechanisms. Employing accurate in vitro and in vivo models to recapitulate the complexities of brain metastasis offers the most promising approach to unravel the intricate cellular and physiological processes involved. Here, we present a comprehensive review of the currently accessible models for studying brain metastasis. We introduce a diverse array of in vitro and in vivo models, including cultured cells using the Transwell system, organoids, microfluidic models, syngeneic models, xenograft models, and genetically engineered models. We have also provided a concise summary of the merits and limitations inherent to each model while identifying the optimal contexts for their effective utilization. This review serves as a comprehensive resource, aiding researchers in making well-informed decisions regarding model selection that align with specific research questions.

4.
CNS Neurosci Ther ; 30(1): e14495, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37849438

RESUMO

AIMS: Glioma is characterized by an immunosuppressed environment and a poor prognosis. The accumulation of Amyloid ß (Aß) leads to an active environment during the early stages of Alzheimer's disease (AD). Aß is also present in glioma tissues; however, the biological and translational implications of Aß in glioma are elusive. METHODS: Immunohistochemical (IHC) staining, Kaplan-Meier (KM) survival analysis and Cox regression analysis on a cohort of 79 patients from our institution were performed to investigate the association between Aß and the malignancy of glioma. Subsequently, the potential of oligomer-Aß42 (OAß42) to inhibit glioma growth was investigated in vivo and in vitro. Immunofluorescence staining and phagocytosis assays were performed to evaluate the activation of microglia. Finally, RNA-seq was utilized to identify the predominant signaling involved in this process and in vitro studies were performed to validate them. RESULTS: A positive correlation between Aß and a favorable prognosis was observed in glioma. Furthermore, OAß42 suppressed glioma growth by enhancing the phagocytic activity of microglia. Insulin-like growth factor 1 (IGF-1) secreted by OAß42-activated microglia was essential in the engulfment process. CONCLUSION: Our study proved an anti-glioma effect of Aß, and microglia could serve as a cellular target for treating glioma with OAß42.


Assuntos
Doença de Alzheimer , Glioma , Humanos , Animais , Camundongos , Peptídeos beta-Amiloides/metabolismo , Microglia , Doença de Alzheimer/metabolismo , Fagocitose , Glioma/metabolismo , Camundongos Transgênicos
5.
Int J Biol Sci ; 19(13): 4311-4326, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37705736

RESUMO

Gliomas develop in unique and complicated environments that nourish tumor cells. The tumor microenvironment (TME) of gliomas comprises heterogeneous cells, including brain-resident cells, immune cells, and vascular cells. Reciprocal interactions among these cells are involved in the evolution of the TME. Moreover, the study of attractive therapeutic strategies that target the TME is transitioning from basic research to the clinic. Mouse models are indispensable tools for dissecting the processes and mechanisms leading to TME evolution. In this review, we overview the paradoxical roles of the TME, as well as the recent progress of mouse models in TME research. Finally, we summarize recent advances in TME-targeting therapeutic strategies.


Assuntos
Glioma , Microambiente Tumoral , Animais , Camundongos , Microambiente Tumoral/genética , Glioma/genética , Modelos Animais de Doenças
7.
Biochem Biophys Res Commun ; 630: 41-49, 2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36137324

RESUMO

Hyperuricemia animal models have long been used for evaluating food-derived anti-hyperuricemia compounds. Fructose and potassium oxonate are commonly used for developing hyperuricemia mouse model. Recent research also developed spontaneous hyperuricemia model by uricase knockout (Uox-/-). In this work, we evaluated 3 kinds of models with the same gene background to illustrate the differences between the treatments. Unlike the uric acid levels in potassium oxonate (224.79 ± 33.62 µmol/L) and Uox-/- groups (458.39 ± 38.29 µmol/L), fructose treatment did not lead to higher serum uric acid level (174.93 ± 30.46 µmol/L) comparing to the control group (153.53 ± 40.96 µmol/L). However, abnormal glycometabolism only developed in the fructose and the Uox-/- group. In addition, anemia, inflammasome and severe renal injury occurred in the Uox-/- group. The Uox-/- mice were then treated with puerarin and allopurinol, and found that puerarin could reduce serum uric acid and alleviated the serious renal damage associated with high uric acid. Thus, the Uox-/- mice could be a suitable model for screening and evaluating anti-hyperuricemia compounds.


Assuntos
Hiperuricemia , Ácido Úrico , Alopurinol , Animais , Modelos Animais de Doenças , Frutose , Hiperuricemia/tratamento farmacológico , Inflamassomos , Camundongos , Urato Oxidase/genética
8.
Food Funct ; 13(20): 10546-10557, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36155703

RESUMO

Hyperuricemia is a purine metabolism disorder, with increasing prevalence worldwide. Here, a high throughput cell model for screening of antihyperuricemic compounds was set up. Human kidney cells (HK2 cells) were stimulated with adenosine and the resulting supernatant and lysate were then analyzed using high performance liquid chromatography (HPLC). The results showed that hypoxanthine content was increased in both HK2 cells supernatant and xanthine oxidase (XO)-overexpressing HK2 cells lysate, but no uric acid was detected due to lower endogenous XO content in these cells. Exogenous XO was added to the supernatant, and then used to evaluate the antihyperuricemic activity of Febuxostat and two the previously identified peptides, Pro-Gly-Ala-Cys-Ser-Asn (PGACSN) and Trp-Met-Leu (WML). By adding exogenous XO, this combined-adenosine-XO-induced hyperuricemia model was optimized and established, and the Febuxostat and peptides were confirmed to significantly reduce uric acid production in the HK2 cells supernatant (p < 0.05). Therefore, this cell model could be recommended for screening potential bioactive antihyperuricemic compounds.


Assuntos
Hiperuricemia , Xantina Oxidase , Adenosina/uso terapêutico , Febuxostat/efeitos adversos , Supressores da Gota , Humanos , Hiperuricemia/metabolismo , Hipoxantinas/uso terapêutico , Peptídeos/química , Ácido Úrico/efeitos adversos , Xantina Oxidase/metabolismo
9.
Biochem Biophys Res Commun ; 591: 7-12, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34990904

RESUMO

Early-stage gastric cancer (GC) is asymptomatic. How to diagnose the early-stage GC is challenging. The sensitivity and specificity of diagnosing signatures for early-stage patients are still poor. Elastic-net-based analysis was used to identify potential diagnostic signatures of early-stage GC. The expression level of candidate gene was evaluated by immunohistochemistry staining. The potential function of candidate gene was verified by overexpressing in vitro. Consensus genes (including GAMT) were identified using the different strengths of the penalty. Surprisingly, GAMT was still identified even if some multicollinear variables were deleted directly. IHC staining showed that there are no GAMT-positive signals in the cell nuclei of all tumor tissues, while GAMT does express in nuclei of adjacent normal tissue. There are 16.33% positive cell nuclei in paracancerous tissues. In addition, the number of larger-area colonies of overexpression-GAMT group, empty-vector group, and AGS group is 70±29.21, 151.33±15.95, and 111.67±22.03, respectively. Number of larger colonies in group with overexpression of GAMT is significantly less than control groups. Elastic-net-penalty-based workflow is a effective tool to identify diagnostic biomarker for early-stage solid tumor. GAMT has strong potential to be the diagnostic biomarker for the early-stage GC.


Assuntos
Biomarcadores Tumorais/metabolismo , Elasticidade , Guanidinoacetato N-Metiltransferase/metabolismo , Neoplasias Gástricas/diagnóstico , Linhagem Celular Tumoral , Proliferação de Células , Análise por Conglomerados , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia
10.
Crit Rev Food Sci Nutr ; 62(17): 4769-4799, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33554630

RESUMO

Wnt signaling pathway is an evolutionarily conserved pathway that control embryonic development, adult tissue homeostasis, and pathological processes of organisms throughout life. However, dysregulation of the Wnt signaling is associated with the occurrence of chronic diseases. In comparison with the application of chemical drugs as traditional treatment for chronic diseases, dietary agents have unique advantages, such as less side effects, multiple targets, convenience in accessibility and higher acceptability in long-term intervention. In this review, we summarized current progress in manipulating the Wnt signaling using food components and its benefits in managing chronic diseases. The underlying mechanisms of bioactive food components in the management of the disease progression via the Wnt signaling was illustrated. Then, the review focused on the function of dietary pattern (which might act via combination of foods with multiple nutrients or food ingredients) on targeting Wnt signaling at multiple level. The potential caveats and challenges in developing new strategy via modulating Wnt-associated diseases with food-based agents and appropriate dietary pattern are also discussed in detail. This review shed light on the understanding of the regulatory effect of food bioactive components on chronic diseases management through the Wnt signaling, which can be expanded to other specific signaling pathway associated with disease.


Assuntos
Doença Crônica/terapia , Ingestão de Alimentos/fisiologia , Alimentos/classificação , Via de Sinalização Wnt/fisiologia , Adulto , Doença Crônica/prevenção & controle , Humanos
11.
Free Radic Biol Med ; 178: 7-17, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34823017

RESUMO

Hyperuricemia (HUA) is a metabolic disorder caused by abnormal purine metabolism, the prevalence of which has increased worldwide. Here, a 3D organoid culture system for mimicking HUA in vitro was established using cultured human liver organoids. Liver organoids can be generated from single hepatocytes and passaged for several months, retaining key morphological features, functional purine metabolism and global gene expression profile. Furthermore, organoids can be differentiated into hepatocytes with high expression of maturation markers including the hepatocyte nuclear factor-4-alpha (HNF4α), E-cadherin (E-Ca), and albumin (ALB). Importantly, organoids can produce high level of uric acid after xanthine induction which is the substrate of xanthine oxidase. Furthermore, the preclinical application potential of this organoid model was verified by measuring the antihyperuricemic effect of the widely used allopurinol, as well as the reported bioactive substance puerarin. The results demonstrate that this novel organoid model could be used for high-throughput screening of both chemical and food-derived compounds with antihyperuricemic bioactivity.


Assuntos
Hiperuricemia , Organoides , Hepatócitos , Humanos , Hiperuricemia/tratamento farmacológico , Fígado , Ácido Úrico
12.
Food Chem ; 374: 131634, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-34838408

RESUMO

Hyperuricemia (HUA) is a metabolic disease caused by disorders of purine metabolism, the prevalence of which has increased worldwide. At present, most drugs aimed at lowering uric acid have toxic side effects, and in vitro screening of uric acid-lowering active substances are inefficient. Here, a long-term 3D human liver organoid culture system with high uric acid for screening and evaluating the efficacy of uric acid-lowering functional compounds. This liver organoids can be established from single hepatocytes and grown for multiple months, while retaining key morphological and functional features. Furthermore, establishment of HUA organoids model was verified by antihyperuricemic drugs allopurinol, as well as reported bioactive peptides, which significantly reduced uric acid production in the liver organoids (p < 0.05). The results demonstrated that it has the potential to be used as a rapid and valid in vitro model to screen antihyperuricemic compounds that mimics in vivo cell growth patterns.


Assuntos
Hiperuricemia , Organoides , Supressores da Gota/uso terapêutico , Humanos , Hiperuricemia/tratamento farmacológico , Fígado , Ácido Úrico
13.
Mol Nutr Food Res ; 65(24): e2100086, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34672083

RESUMO

SCOPE: Aging has become one of major concern worldwide. It is therefore of great significance in finding food resources as therapeutic candidates for aging-related functional decline improvement and prevention. This study aimed to define the potency of Haematococcus pluvialis (H. pluvialis) as an anti-aging food resource. METHODS AND RESULTS: Yeast is used to explore the anti-aging effects of H. pluvialis. The result showed that H. pluvialis extract could effectively extend yeast chronological lifespan (CLS) by reducing intracellular reactive oxygen species (ROS) levels, promoting mitochondrial membrane potential (MMP) levels and accumulating storage carbohydrate (glycogen). Subsequently, Slc25a46 knockout (Slc25a46-/- ) mice with mitochondrial dysfunction are fed with 100 mg kg-1 H. pluvialis extracts for 10 days. The in vivo data demonstrated that H. pluvialis extract could effectively improve the phenotypic deficits, including underweight, muscle weakness, redox imbalance, and mitochondrial respiratory chain dysfunction, etc., in Slc25a46-/- mice. CONCLUSIONS: This work highlights that the mitochondria may be a potential therapeutic target for combating aging, and demonstrated that H. pluvialis, as a dietary supplement, may potentially be an effective preventive substance that may contribute to the promotion of healthy aging.


Assuntos
Longevidade , Saccharomyces cerevisiae , Animais , Técnicas de Inativação de Genes , Camundongos , Camundongos Knockout , Oxirredução
14.
Biochem Biophys Res Commun ; 568: 116-123, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34217010

RESUMO

Advanced CUBIC clearing method can clear diverse organs and even the entire body of a mouse to enable high-resolution 3D imaging. Advanced CUBIC reagent has often been used due to its low toxicity and easy preparation. However, Advanced CUBIC has a long experimental cycle, which reduces the efficiency of data acquisition. In this study, we first tracked the clarity changes of different organs cleared by Advanced CUBIC and identified the shortest time required for optimal transparency in individual organs. We then introduced ultrasound processing and developed a decolorization cocktail to optimize the clearing efficiency of the Advanced CUBIC method. With the optimized clearing CUBIC-Plus method, we achieved high resolution 3D imaging of mouse organs. Our CUBIC-Plus provides an efficient procedure to clear different organ for 3D imaging at high resolution.


Assuntos
Imunofluorescência/métodos , Imageamento Tridimensional/métodos , Microscopia Confocal/métodos , Animais , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Cor , Feminino , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência/métodos , Ondas Ultrassônicas
15.
Transl Lung Cancer Res ; 10(5): 2252-2277, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34164274

RESUMO

BACKGROUND: As lymphatic vessel is a major route for solid tumor metastasis, they are considered an essential part of tumor drainage conduits. Apart from forming the walls of lymphatic vessels, lymphatic endothelial cells (LECs) have been found to play multiple other roles in the tumor microenvironment, calling for a more in-depth review. We hope that this review may help researchers gain a detailed understanding of this fast-developing field and shed some light upon future research. METHODS: To achieve an informative review of recent advance, we carefully searched the Medline database for English literature that are openly published from the January 1995 to December 2020 and covered the topic of LEC or lymphangiogenesis in tumor progression and therapies. Two different authors independently examined the literature abstracts to exclude possible unqualified ones, and 310 papers with full texts were finally retrieved. RESULTS: In this paper, we discussed the structural and molecular basis of tumor-associated LECs, together with their roles in tumor metastasis and drug therapy. We then focused on their impacts on tumor cells, tumor stroma, and anti-tumor immunity, and the molecular and cellular mechanisms involved. Special emphasis on lung cancer and possible therapeutic targets based on LECs were also discussed. CONCLUSIONS: LECs can play a much more complex role than simply forming conduits for tumor cell dissemination. Therapies targeting tumor-associated lymphatics for lung cancer and other tumors are promising, but more research is needed to clarify the mechanisms involved.

16.
Brain Behav Immun ; 96: 227-238, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34111528

RESUMO

Gut microbiota is proven to be involved in the development of beta amyloid (Aß) pathology in Alzheimer's disease (AD). Since there are difficulties in translating microbiota findings based on germ-free mice into clinical practice, here, we used short-term antibiotic cocktail treatment to develop a novel model with a near-germ-free status and without impacting Aß pathology. Three months old APPSWE/PS1ΔE9 mice were fed with antibiotic cocktails for two weeks by gavage to obtain a near "germ-free" status, and then received the donor fecal matter from the 16 months old APPSWE/PS1ΔE9 mice for 7 consecutive days. Fecal pellets were collected prior to antibiotics treatment, following antibiotic exposure, prior to and following fecal microbiota transplantation for gut microbiota analysis. Also, Aß pathology, astrocyte and microglia morphology were further explored. Pre-antibiotic-treated mice successfully allowed engraftment of gut microbiota following 7 consecutive days gavage with aged APPSWE/PS1ΔE9 mice microbiota. Microbiota reconstitution by transplantation was largely attributable to the donor source (e.g. g_Coriobacteriaceae and g_Clostridium) and led to a significant increase in Aß plaques. Surprisingly, astrocyte activation around Aß plaques was suppressed rather than microglia, the well-recognized plaque phagocytic cell type in Aß clearance, following microbiota engraftment. Our findings provide a novel framework for understanding the mechanisms of AD through the gut-brain axis and the translation of gut microbiota manipulation from bench to clinical practice.


Assuntos
Doença de Alzheimer , Microbiota , Doença de Alzheimer/terapia , Peptídeos beta-Amiloides , Animais , Antibacterianos , Modelos Animais de Doenças , Transplante de Microbiota Fecal , Camundongos , Camundongos Transgênicos
17.
JAMA Intern Med ; 181(3): 407-408, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33346813
18.
J Gerontol A Biol Sci Med Sci ; 76(3): 440-447, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33277645

RESUMO

The mitochondrial theory of aging postulates that accumulation of mtDNA mutations and mitochondrial dysfunction are responsible for producing aging phenotypes. To more comprehensively explore the complex relationship between aging and mitochondria dysfunction, we have developed a mouse model with Slc25a46 knockout, a nuclear gene described as encoding mitochondrial carriers, by CRISPR/Cas9 gene editing to mimic some typical aging phenotypes in human. Slc25a46-/- mice present segmental premature aging phenotypes characterized by shortened life span of no more than 2 months, obviously defective motor ability, gastrocnemius muscle atrophy, and imbalance of redox level in brain and liver. The underlying mechanism for multiple organ disorder may attribute to mitochondrial dysfunction, which is mainly manifested in the damaged mitochondrial structure (eg, vacuolar structure, irregular swelling, and disorganized cristae) and an age-associated decrease in respiratory chain enzyme (mainly complex I and IV) activity. In summary, our study suggests that the Slc25a46-/- mouse is a valid animal model for segmental aging-related pathologies studies based on mitochondrial theory, generating a new platform to both understand mechanisms between aging and mitochondria dysfunction as well as to design mitochondria-based therapeutic strategies to improve mitochondrial quality, and thereby the overall healthspan.


Assuntos
Envelhecimento/patologia , Envelhecimento/fisiologia , Doenças Mitocondriais/etiologia , Proteínas Mitocondriais/fisiologia , Transtornos Motores/etiologia , Estresse Oxidativo/fisiologia , Animais , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Knockout , Oxirredução
19.
Cell ; 180(3): 502-520.e19, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-31983537

RESUMO

The tumor microenvironment (TME) is critical for tumor progression. However, the establishment and function of the TME remain obscure because of its complex cellular composition. Using a mouse genetic system called mosaic analysis with double markers (MADMs), we delineated TME evolution at single-cell resolution in sonic hedgehog (SHH)-activated medulloblastomas that originate from unipotent granule neuron progenitors in the brain. First, we found that astrocytes within the TME (TuAstrocytes) were trans-differentiated from tumor granule neuron precursors (GNPs), which normally never differentiate into astrocytes. Second, we identified that TME-derived IGF1 promotes tumor progression. Third, we uncovered that insulin-like growth factor 1 (IGF1) is produced by tumor-associated microglia in response to interleukin-4 (IL-4) stimulation. Finally, we found that IL-4 is secreted by TuAstrocytes. Collectively, our studies reveal an evolutionary process that produces a multi-lateral network within the TME of medulloblastoma: a fraction of tumor cells trans-differentiate into TuAstrocytes, which, in turn, produce IL-4 that stimulates microglia to produce IGF1 to promote tumor progression.


Assuntos
Astrócitos/metabolismo , Carcinogênese/metabolismo , Transdiferenciação Celular , Neoplasias Cerebelares/metabolismo , Meduloblastoma/metabolismo , Comunicação Parácrina , Animais , Linhagem da Célula , Neoplasias Cerebelares/patologia , Modelos Animais de Doenças , Feminino , Proteínas Hedgehog/metabolismo , Xenoenxertos , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Interleucina-4/genética , Interleucina-4/metabolismo , Masculino , Meduloblastoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Microambiente Tumoral
20.
BMJ Nutr Prev Health ; 3(2): 308-319, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33521542

RESUMO

OBJECTIVE: To assess the knowledge on country-specific nutrition situation, perceptions of the nutrition curricula and factors influencing capacity to offer nutrition guidance among medical students studying internationally in China compared with their home-country counterparts. DESIGN: Cross-sectional study. SETTINGS: China, Ghana, India and Montenegro. PARTICIPANTS: International medical students in China and medical students studying in their home countries of Ghana, India and Montenegro. MAIN MEASURE: An online semistructured questionnaire was administered using WeChat for international students and Microsoft Forms for home-country medical students to assess students' perceived knowledge and significance of nutrition, knowledge of country-specific nutrition situation, perceptions of the nutrition curricula and perceived capacity to offer nutrition counselling. RESULT: In all, 190 medical students responded to the survey: 110 international students studying in China and 80 home-country students from Ghana (40), India (20) and Montenegro (20). Home-country students rated the importance of nutrition in health and disease development higher than international students (p<0.05). International students reported not having any specific nutrition courses while home-country students had nutrition courses as part of their curriculum. Only 8.2% of international students and 13.8% of home-country students were able to correctly mention any specific national nutrition guidelines of their home countries. Home-country students were more likely to provide correct nutrition recommendations for infants (χ²(3)=26.349; p=0.001), pregnancy (χ²(3)=9.793; p=0.007), lactating mothers (χ²(3)=9.112; p=0.011), diabetes (χ²(3)=13.619; p=0.001), hypertension (χ²(3)=12.022; p=0.002), overweight/obesity (χ²(3)=8.896; p=0.012) and undernutrition (χ²(3)=7.670; p=0.022) compared with international students. Practical nutrition courses, hours of nutrition education and how often students were asked nutrition-related questions tended to affect and predict the adequacy of nutrition education received and the perceived confidence for nutrition counselling. CONCLUSION: International medical students in China are less familiar with the nutrition context in their respective home countries compared with their home-country counterparts. Medical schools in China that train significant numbers of international students need to support these students to become familiar with their respective countries' nutrition contexts.

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