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1.
J Vis Exp ; (200)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37929996

RESUMO

Mesenchymal stromal cells (MSCs) are adult pluripotent stem cells which have been widely used in regenerative medicine. As somatic tissue-derived MSCs are restricted by limited donation, quality variations, and biosafety, the past 10 years have seen a great rise in efforts to generate MSCs from human induced pluripotent stem cells (hiPSCs). Past and recent efforts in the differentiation of hiPSCs into MSCs have been centered around two culture methodologies: (1) the formation of embryoid bodies (EBs) and (2) the use of monolayer culture. This protocol describes these two representative methods in deriving MSC from hiPSCs. Each method presents its advantages and disadvantages, including time, cost, cell proliferation ability, the expression of MSC markers, and their capability of differentiation in vitro. This protocol demonstrates that both methods can derive mature and functional MSCs from hiPSCs. The monolayer method is characterized by lower cost, simpler operation, and easier osteogenic differentiation, while the EB method is characterized by lower time consumption.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Mesenquimais , Adulto , Humanos , Osteogênese , Diferenciação Celular , Corpos Embrioides
2.
Theranostics ; 13(13): 4356-4375, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37649595

RESUMO

Background: Cisplatin is a widely used anti-tumor agent but its use is frequently limited by nephrotoxicity. Transient receptor potential melastatin 2 (TRPM2) is a non-selective cation channel which is generally viewed as a sensor of oxidative stress, and increasing evidence supports its link with autophagy, a critical process for organelle homeostasis. Methods: Cisplatin-induced cell injury and mitochondrial damage were both assessed in WT and Trpm2-knockout mice and primary cells. RNA sequencing, immunofluorescence staining, immunoblotting and flowcytometry were applied to interpret the mechanism of TRPM2 in cisplatin nephrotoxicity. Results: Knockout of TRPM2 exacerbates renal dysfunction, tubular injury and cell apoptosis in a model of acute kidney injury (AKI) induced by treatment with cisplatin. Cisplatin-caused tubular mitochondrial damage is aggravated in TRPM2-deficient mice and cells and, conversely, alleviated by treatment with Mito-TEMPO, a mitochondrial ROS scavenger. TRPM2 deficiency hinders cisplatin-induced autophagy via blockage of Ca2+ influx and subsequent up-regulation of AKT-mTOR signaling. Consistently, cisplatin-induced tubular mitochondrial damage, cell apoptosis and renal dysfunction in TRPM2-deficient mice are mitigated by treatment with a mTOR inhibitor. Conclusion: Our results suggest that the TRPM2 channel plays a protective role in cisplatin-induced AKI via modulating the Ca2+-AKT-mTOR signaling pathway and autophagy, providing novel insights into the pathogenesis of kidney injury.


Assuntos
Injúria Renal Aguda , Canais de Cátion TRPM , Animais , Camundongos , Camundongos Knockout , Cisplatino/toxicidade , Proteínas Proto-Oncogênicas c-akt , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Autofagia
4.
Hum Mol Genet ; 30(5): 321-330, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33481017

RESUMO

Most genetic variants for colorectal cancer (CRC) identified in genome-wide association studies (GWAS) are located in intergenic regions, implying pathogenic dysregulations of gene expression. However, comprehensive assessments of target genes in CRC remain to be explored. We conducted a multi-omics analysis using transcriptome and/or DNA methylation data from the Genotype-Tissue Expression, The Cancer Genome Atlas and the Colonomics projects. We identified 116 putative target genes for 45 GWAS-identified variants. Using summary-data-based Mendelian randomization approach (SMR), we demonstrated that the CRC susceptibility for 29 out of the 45 CRC variants may be mediated by cis-effects on gene regulation. At a cutoff of the Bonferroni-corrected PSMR < 0.05, we determined 66 putative susceptibility genes, including 39 genes that have not been previously reported. We further performed in vitro assays for two selected genes, DIP2B and SFMBT1, and provide functional evidence that they play a vital role in colorectal carcinogenesis via disrupting cell behavior, including migration, invasion and epithelial-mesenchymal transition. Our study reveals a large number of putative novel susceptibility genes and provides additional insight into the underlying mechanisms for CRC genetic risk loci.


Assuntos
Carcinogênese/genética , Neoplasias Colorretais/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Proteínas do Tecido Nervoso/genética , Proteínas Repressoras/genética , Transcriptoma , Linhagem Celular Tumoral , Proliferação de Células , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Genoma , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco
5.
Gastroenterology ; 160(4): 1164-1178.e6, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33058866

RESUMO

BACKGROUND AND AIMS: Susceptibility genes and the underlying mechanisms for the majority of risk loci identified by genome-wide association studies (GWAS) for colorectal cancer (CRC) risk remain largely unknown. We conducted a transcriptome-wide association study (TWAS) to identify putative susceptibility genes. METHODS: Gene-expression prediction models were built using transcriptome and genetic data from the 284 normal transverse colon tissues of European descendants from the Genotype-Tissue Expression (GTEx), and model performance was evaluated using data from The Cancer Genome Atlas (n = 355). We applied the gene-expression prediction models and GWAS data to evaluate associations of genetically predicted gene-expression with CRC risk in 58,131 CRC cases and 67,347 controls of European ancestry. Dual-luciferase reporter assays and knockdown experiments in CRC cells and tumor xenografts were conducted. RESULTS: We identified 25 genes associated with CRC risk at a Bonferroni-corrected threshold of P < 9.1 × 10-6, including genes in 4 novel loci, PYGL (14q22.1), RPL28 (19q13.42), CAPN12 (19q13.2), MYH7B (20q11.22), and MAP1L3CA (20q11.22). In 9 known GWAS-identified loci, we uncovered 9 genes that have not been reported previously, whereas 4 genes remained statistically significant after adjusting for the lead risk variant of the locus. Through colocalization analysis in GWAS loci, we additionally identified 12 putative susceptibility genes that were supported by TWAS analysis at P < .01. We showed that risk allele of the lead risk variant rs1741640 affected the promoter activity of CABLES2. Knockdown experiments confirmed that CABLES2 plays a vital role in colorectal carcinogenesis. CONCLUSIONS: Our study reveals new putative susceptibility genes and provides new insight into the biological mechanisms underlying CRC development.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Predisposição Genética para Doença , Modelos Genéticos , Alelos , Carcinogênese/genética , Estudos de Casos e Controles , Estudos de Coortes , Neoplasias Colorretais/epidemiologia , Técnicas de Silenciamento de Genes , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas/genética , RNA-Seq , Fatores de Risco , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Int J Biol Macromol ; 139: 1035-1045, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412265

RESUMO

Colorectal cancer (CRC) is a prevalent and fatal cancer. Oral administration provided the potential for in situ treatment of the colorectal cancer. However, drugs couldn't be well-absorbed mainly due to its degradation in the gastric area and poor intestinal permeability. In this study, we synthesized deoxycholic acid and hydroxybutyl decorated chitosan nanoparticles (DAHBC NPs) as oral curcumin (CUR) delivery system for colorectal cancer treatment. DAHBC with lower critical solution temperature (LCST) below 37 °C (27-33 °C) was obtained. DAHBC NPs were correspondingly stable in simulated gastric conditions (pH 1.2, 37 °C), due to the offset of size change between pH-responsive expansion and thermo-responsive shrinkage. In simulated intestinal tract (pH 7.0-7.4, 37 °C), DAHBC NPs exhibited burst release of CUR owing to the onefold effect of thermo-responsive shrinkage. DAHBC27 NPs showed the minimum CUR leakage (~10%) in simulated gastric conditions, because a furthest temperature-sensitive shrinkage caused by the lowest LCST offset the expansion in acid environment. DAHBC27 NPs induced ~10-fold increased (P < 0.05) CUR absorption by paracellular transport pathway, compared to the free CUR. Thus, DAHBC NPs stabilized in the gastric environment may be a promising oral drugs delivery system for effective in situ colorectal cancer therapy.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Curcumina/administração & dosagem , Curcumina/química , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Mucosa Gástrica/metabolismo , Administração Oral , Adsorção , Células CACO-2 , Quitosana/análogos & derivados , Quitosana/química , Curcumina/uso terapêutico , Ácido Desoxicólico/química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Hemólise/efeitos dos fármacos , Humanos , Absorção Intestinal , Teste de Materiais , Nanopartículas/química , Temperatura
7.
Artigo em Inglês | MEDLINE | ID: mdl-30008786

RESUMO

Herb mixtures are widely used for treatment of the menopausal syndrome long before the hormonal therapy. However, there is insufficient data for herb remedies in treating menopausal syndromes. Here we aim to investigate the effect of ZhenRongDan (ZRD) in balancing female hormones, regulating expression of estrogen receptors (ERs), and preventing organ atrophy in menopausal rats. Rats that underwent bilateral ovariectomy were used in the experiments; the effects of ZRD on serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), and estradiol (E2) levels were observed. Histology of vagina and ERs expression in vagina, uterus, and adrenal gland were also examined. ELISAs were used to analyze the changes of FSH, LH, PRL, and E2 in serum, and the morphological changes of the cervical epithelium cells were observed by Hematoxylin & Eosin (H&E) staining. Immunohistochemistry and western blot were applied to detect estrogen receptors subtypes alpha (ERα) and beta (ERß) expression in vagina, uterus, and adrenal gland. We found that ZRD could significantly reduce the weight of the adrenal gland and increase the weight of the uterus. It could decrease the release of FSH and LH as well as increasing E2 and PRL levels. Furthermore, ZRD could improve the number of cervical vaginal epithelial cells and increase the thickness of the vaginal wall. And the altered expressions of ERα and ERß are also restored by ZRD. ZRD could obviously relieve the endocrine disorders, modulate organ atrophy, and restore ERα and ERß expression in the ovariectomized rat model.

8.
Sci Rep ; 7(1): 62, 2017 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-28246402

RESUMO

Radiation-induced lung fibrosis (RILF) is a long-term adverse effect of curative radiotherapy. The accumulation of myofibroblasts in fibroblastic foci is a pivotal feature of RILF. In the study, we found the inhibitory effect of grape seed proanthocyanidins (GSPs) on irradiation-induced differentiation of human fetal lung fibroblasts (HFL1). To explore the mechanism by which GSPs inhibit fibroblast differentiation, we measured the reactive oxygen species (ROS) levels, mitochondrial function, mitochondrial dynamics, glycolysis and the signaling molecules involved in fibroblast transdifferentiation. GSPs significantly reduced the production of cellular and mitochondrial ROS after radiation. The increases in mitochondrial respiration, proton leak, mitochondrial ATP production, lactate release and glucose consumption that occurred in response to irradiation were ameliorated by GSPs. Furthermore, GSPs increased the activity of complex I and improved the mitochondrial dynamics, which were disturbed by irradiation. In addition, the elevation of phosphorylation of p38MAPK and Akt, and Nox4 expression induced by irradiation were attenuated by GSPs. Blocking Nox4 attenuated irradiation-mediated fibroblast differentiation. Taken together, these results indicate that GSPs have the ability to inhibit irradiation-induced fibroblast-to-myofibroblast differentiation by ameliorating mitochondrial dynamics and mitochondrial complex I activity, regulating mitochondrial ROS production, ATP production, lactate release, glucose consumption and thereby inhibiting p38MAPK-Akt-Nox4 pathway.


Assuntos
Fibroblastos/efeitos dos fármacos , Fibroblastos/efeitos da radiação , Extrato de Sementes de Uva/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/efeitos da radiação , Proantocianidinas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/efeitos da radiação , Linhagem Celular , Fibroblastos/citologia , Raios gama/efeitos adversos , Glicólise , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Pulmão/citologia , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo
9.
Colloids Surf B Biointerfaces ; 148: 147-156, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27591946

RESUMO

A series of deoxycholate-chitosan-hydroxybutyl (DAHBCs) with different degrees of substitution (DS) of hydrophobic deoxycholate (DOCA) were successfully synthesized. The lower critical solution temperature (LCST) of various DAHBCs could be adjusted from 35.4°C to 42.1°C by controlling the graft density of DOCA. DAHBCs could self-assemble into nanoparticles (NPs) which gradually evolved from irregular aggregates to spherical particles with the decrease of the DS of DOCA groups. The size of DAHBCs NPs ranged from 100nm to 250nm and their zeta potential varied between 3.85 and 12.37mV. Hemolysis tests and protein adsorption assay exhibited DAHBCs NPs had few adverse effects on the blood components even at a concentration as high as 1mg/mL. DAHBCs NPs showed high curcumin (CUR) encapsulation efficiency up to 80%. CUR-loaded DAHBCs NPs displayed thermal-dependent drug release profiles, and the release rate of CUR (∼75%) was significantly (p<0.05) accelerated at a temperature above the LCST compared with that (∼40%) below the LCST. Cytotoxicity analysis identified no toxicity associated with DAHBCs NPs at a concentration up to 0.5mg/mL. However, when the cells were incubated with the CUR-loaded NPs, their growth was significantly inhibited at 43°C (>LCST), demonstrating the thermal-responsive release of encapsulated cargoes from the NPs. With the capacity to control the LCST of DAHBCs NPs at specific temperatures, it could be speculated that DAHBCs NPs might serve as a promising thermo-responsive nanoplatform for the delivery of antitumor drugs.


Assuntos
Antineoplásicos/administração & dosagem , Materiais Biocompatíveis , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Humanos , Interações Hidrofóbicas e Hidrofílicas
10.
Colloids Surf B Biointerfaces ; 145: 492-501, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27236511

RESUMO

Here we described nano-polyplexes (NPs) made of oleoyl-carboxymethy-chitosan (OCMCS)/hyaluronic acid (HA) as novel potential carriers for oral gene vaccines delivery. Aerolysin gene (aerA) of Aeromonas hydrophila as microbial antigen was efficiently loaded to form OCMCS-HA/aerA (OHA) NPs. OHA NPs performed the optimal parameters, i.e. smallest (154.5±9.4nm), positive charged (+7.9±0.5mV) and monodispersed system with the N/P ratio of 5 and OCMCS/HA weight ratio of 4. Upon the introduction of HA, OHA NPs was beneficial for the DNA release in intestinal environments in comparison to OA NPs. The mean fluorescence intensity detected in Caco-2 cells incubated with OHA NPs was about 2.5-fold higher than that of OA NPs; however, it decreased significantly in the presence of excess free HA. The OHA NPs and OA NPs decreased the transepithelial electric resistance (TEER) of Caco-2 monolayers obviously and induced increasing the apparent permeability coefficient (Papp) of DNA by 5.45-6.09 folds compared with free DNA. Significantly higher (P<0.05) antigen-specific antibodies were detected in serum after orally immunized with OHA NPs than that immunized with OA NPs and DNA alone in carps. These results enable the OHA NPs might resolve challenges arising from gastrointestinal damage to gene antigens, and offer an approach applicable for oral vaccination.


Assuntos
Quitosana/química , Ácido Hialurônico/química , Nanopartículas/química , Vacinas de DNA/administração & dosagem , Células CACO-2 , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Humanos
11.
Sci Rep ; 5: 17909, 2015 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-26643045

RESUMO

Silkworm pupae oil derived from reeling waste is a rich source of α-linolenic acid (ALA), which has multipal applications. ALAs were added in sn-1, 3 positions in a triacylglycerol (TAG) to produce an APA-human milk fat analogues (APA-HMFAs, A: α-linolenic acid, P: palmitic acid). The optimum condition is that tripalmitin to free fatty acids of 1:12 (mole ratio) at 65 °C for 48 h using lipase Lipozyme RM IM. Results show that, the major TAG species that comprised APA-HMFAs were rich in ALA and palmitic acid, which contained 64.52% total unsaturated fatty acids (UFAs) and 97.05% PA at the sn-2 position. The melting point of APA was -27.5 °C which is much lower than tripalmitin (40.5 °C) indicating more plastic character. In addition, the practical application of alkyl caffeates as liposoluble antioxidants in APA was developed. Alkyl caffeate showed a superior IC50 (1.25-1.66 µg/mL) compared to butyl hydroxy anisd (1.67 µg/mL) and L-ascorbic acid-6-palmitate (L-AP) (1.87 µg/mL) in DPPH analysis. The addition of ethyl caffeate to oil achieved a higher UFAs content (73.58%) at high temperatures. Overall, APA was obtained from silkworm pupae oil successfully, and the addition of caffeates extended storage ranges for APA-HMFAs.


Assuntos
Bombyx/química , Leite Humano/química , Óleos/química , Ácido alfa-Linolênico/química , Animais , Antioxidantes/química , Esterificação , Ácidos Graxos/química , Humanos , Lipídeos/química , Pupa/química , Temperatura
12.
PLoS One ; 9(4): e95909, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24760050

RESUMO

Caffeic acid (CA) is distributed widely in nature and possesses strong antioxidant activity. However, CA has lower solubility in non-polar media, which limits its application in fat-soluble food. To increase the lipophilicity of natural antioxidant CA, a series of alkyl caffeates were synthesized and their antioxidant and antitumor activities were investigated. The antioxidant parameters, including the induction period, acid value and unsaturated fatty acid content, of the alkyl caffeates in edible oil were firstly investigated. The results indicated that alkyl caffeates had a lower DPPH IC50 (14-23 µM) compared to CA, dibutyl hydroxy toluene (BHT) and Vitamin C (24-51 µM), and significantly inhibited four human cancer cells (SW620, SW480, SGC7901 and HepG2) with inhibition ratio of 71.4-78.0% by a MTT assay. With regard to the induction period and acid value assays, methyl and butyl caffeates had higher abilities than BHT to restrain the oxidation process and improve the stability of edible oil. The addition of ethyl caffeate to oil allowed maintenance of a higher unsaturated fatty acid methyl ester content (68.53%) at high temperatures. Overall, the alkyl caffeats with short chain length (n<5) assessed better oxidative stability than those with long chain length. To date, this is the first report to the correlations among the antioxidant activity, anticancer activity and oxidative stability of alkyl caffeates.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Ácidos Cafeicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Óleos de Plantas/química , Antineoplásicos/síntese química , Antioxidantes/síntese química , Compostos de Bifenilo/metabolismo , Ácidos Cafeicos/síntese química , Linhagem Celular Tumoral , Estabilidade de Medicamentos , Ácidos Graxos Insaturados/metabolismo , Células Hep G2 , Humanos , Picratos/metabolismo
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