Mecanismo de células dendríticas derivadas de sangre periférica humana en la regulación de la autofagia en células de carcinoma / Mechanism of human peripheral blood-derived dendritic cells in the regulation of autophagy in carcinoma cells

Resumen Introducción: Las células dendríticas (CD) están involucradas en el reconocimiento, respuesta y modulación inmunológicos relacionados con la aparición del cáncer. Objetivo: Explorar el mecanismo de las CD en la inhibición de la autofagia de las células del hepatoma. Métodos: Células mononucleares de sangre periférica humana se aislaron mediante centrifugación en gradiente de densidad de Ficoll y se indujeron en CD, las cuales fueron cocultivadas con células HepG2 por ensayo de migración Transwell. La actividad de las células HepG2 se determinó mediante ensayo CCK8. La expresión del índice de autofagia LC3 se midió con análisis de transferencia Western y la expresión y secreción de citocinas mediante qRT-PCR y ELISA. Resultados: En el sistema de cocultivo, las CD redujeron la viabilidad de HepG2; la expresión de IL-2, IL-12, IL-10 e IFN-γ en CD también se inhibió significativamente, si bien IL-2 e IFN-γ aún se expresaron 0.6 y 0.53 más que en el grupo de control. Conclusión: Las CD pueden regular la autofagia de las células del carcinoma hepatocelular. El mecanismo puede estar relacionado con la síntesis y liberación de citocinas como IL-2, IL-12 e IFN-γ por parte de las CD.

Abstract Introduction: Dendritic cells (DC) are involved in immune recognition, response and immunomodulation mechanisms related to the onset of cancer. Objective: To explore DCs mechanism in the inhibition of autophagy in hepatoma cells. Methods: Human peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation and induced into DCs, which were co-cultured with HepG2 cells by Transwell migration assay. HepG2 cell activity was determined using the CCK8 assay. LC3 autophagy index expression was measured with Western blot analysis, and the expression and secretion of cytokines, with qRT-PCR and ELISA. Results: In the co-culture system, DCs were able to reduce HepG2 cells viability; IL-2, IL-12, IL-10 and IFN-γ expression in DCs was also significantly inhibited, although IL-2 and IFN-γ were still expressed 0.6 and 0.53 more than in the control group. Conclusion: DCs can regulate autophagy in hepatocellular carcinoma cells. The mechanism may be related to the synthesis and release of cytokines such as IL-2, IL-12 and IFN-γ by DCs.

Mechanism of human peripheral blood-derived dendritic cells in the regulation of autophagy in carcinoma cells.

INTRODUCTION: Dendritic cells (DC) are involved in immune recognition, response and immunomodulation mechanisms related to the onset of cancer. OBJECTIVE: To explore DCs mechanism in the inhibition of autophagy in hepatoma cells. METHODS: Human peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation and induced into DCs, which were co-cultured with HepG2 cells by Transwell migration assay. HepG2 cell activity was determined using the CCK8 assay. LC3 autophagy index expression was measured with Western blot analysis, and the expression and secretion of cytokines, with qRT-PCR and ELISA. RESULTS: In the co-culture system, DCs were able to reduce HepG2 cells viability; IL-2, IL-12, IL-10 and IFN-γ expression in DCs was also significantly inhibited, although IL-2 and IFN-γ were still expressed 0.6 and 0.53 more than in the control group. CONCLUSION: DCs can regulate autophagy in hepatocellular carcinoma cells. The mechanism may be related to the synthesis and release of cytokines such as IL-2, IL-12 and IFN-γ by DCs.

INTRODUCCIÓN: Las células dendríticas (CD) están involucradas en el reconocimiento, respuesta y modulación inmunológicos relacionados con la aparición del cáncer. OBJETIVO: Explorar el mecanismo de las CD en la inhibición de la autofagia de las células del hepatoma. MÉTODOS: Células mononucleares de sangre periférica humana se aislaron mediante centrifugación en gradiente de densidad de Ficoll y se indujeron en CD, las cuales fueron cocultivadas con células HepG2 por ensayo de migración Transwell. La actividad de las células HepG2 se determinó mediante ensayo CCK8. La expresión del índice de autofagia LC3 se midió con análisis de transferencia Western y la expresión y secreción de citocinas mediante qRT-PCR y ELISA. RESULTADOS: En el sistema de cocultivo, las CD redujeron la viabilidad de HepG2; la expresión de IL-2, IL-12, IL-10 e IFN-γ en CD también se inhibió significativamente, si bien IL-2 e IFN-γ aún se expresaron 0.6 y 0.53 más que en el grupo de control. CONCLUSIÓN: Las CD pueden regular la autofagia de las células del carcinoma hepatocelular. El mecanismo puede estar relacionado con la síntesis y liberación de citocinas como IL-2, IL-12 e IFN-γ por parte de las CD.

Magnetosome magnetite biomineralization in a flagellated protist: evidence for an early evolutionary origin for magnetoreception in eukaryotes.

The most well-recognized magnetoreception behaviour is that of the magnetotactic bacteria (MTB), which synthesize membrane-bounded magnetic nanocrystals called magnetosomes via a biologically controlled process. The magnetic minerals identified in prokaryotic magnetosomes are magnetite (Fe3 O4 ) and greigite (Fe3 S4 ). Magnetosome crystals, regardless of composition, have consistent, species-specific morphologies and single-domain size range. Because of these features, magnetosome magnetite crystals possess specific properties in comparison to abiotic, chemically synthesized magnetite. Despite numerous discoveries regarding MTB phylogeny over the last decades, this diversity is still considered underestimated. Characterization of magnetotactic microorganisms is important as it might provide insights into the origin and establishment of magnetoreception in general, including eukaryotes. Here, we describe the magnetotactic behaviour and characterize the magnetosomes from a flagellated protist using culture-independent methods. Results strongly suggest that, unlike previously described magnetotactic protists, this flagellate is capable of biomineralizing its own anisotropic magnetite magnetosomes, which are aligned in complex aggregations of multiple chains within the cell. This organism has a similar response to magnetic field inversions as MTB. Therefore, this eukaryotic species might represent an early origin of magnetoreception based on magnetite biomineralization. It should add to the definition of parameters and criteria to classify biogenic magnetite in the fossil record.

TNF-α inhibits SCF, ghrelin, and substance P expressions through the NF-κB pathway activation in interstitial cells of Cajal.

Ulcerative colitis is a chronic inflammatory disease of the colon where intestinal motility is disturbed. Interstitial cells of Cajal (ICC) are required to maintain normal intestinal motility. In the present study, we assessed the effect of tumor necrosis factor-alpha (TNF-α) on viability and apoptosis of ICC, as well as on the expression of stem cell factor (SCF), ghrelin, and substance P. ICC were derived from the small intestines of Swiss albino mice. Cell viability and apoptosis were measured using CCK-8 assay and flow cytometry, respectively. ELISA was used to measure the concentrations of IL-1ß, IL-6, ghrelin, substance P, and endothelin-1. Quantitative RT-PCR was used to measure the expression of SCF. Western blotting was used to measure the expression of apoptosis-related proteins, interleukins, SCF, and NF-κB signaling pathway proteins. TNF-α induced inflammatory injury in ICC by decreasing cell viability and increasing apoptosis and levels of IL-1ß and IL-6. TNF-α decreased the levels of SCF, ghrelin, and substance P, but had no effect on endothelin-1. TNF-α down-regulated expressions of SCF, ghrelin, and substance P by activating the NF-κB pathway in ICC. In conclusion, TNF-α down-regulated the expressions of SCF, ghrelin, and substance P via the activation of the NF-κB pathway in ICC.

TNF-α inhibits SCF, ghrelin, and substance P expressions through the NF-κB pathway activation in interstitial cells of Cajal

Ulcerative colitis is a chronic inflammatory disease of the colon where intestinal motility is disturbed. Interstitial cells of Cajal (ICC) are required to maintain normal intestinal motility. In the present study, we assessed the effect of tumor necrosis factor-alpha (TNF-α) on viability and apoptosis of ICC, as well as on the expression of stem cell factor (SCF), ghrelin, and substance P. ICC were derived from the small intestines of Swiss albino mice. Cell viability and apoptosis were measured using CCK-8 assay and flow cytometry, respectively. ELISA was used to measure the concentrations of IL-1β, IL-6, ghrelin, substance P, and endothelin-1. Quantitative RT-PCR was used to measure the expression of SCF. Western blotting was used to measure the expression of apoptosis-related proteins, interleukins, SCF, and NF-κB signaling pathway proteins. TNF-α induced inflammatory injury in ICC by decreasing cell viability and increasing apoptosis and levels of IL-1β and IL-6. TNF-α decreased the levels of SCF, ghrelin, and substance P, but had no effect on endothelin-1. TNF-α down-regulated expressions of SCF, ghrelin, and substance P by activating the NF-κB pathway in ICC. In conclusion, TNF-α down-regulated the expressions of SCF, ghrelin, and substance P via the activation of the NF-κB pathway in ICC.

Effects of R219K polymorphism of ATP-binding cassette transporter 1 gene on serum lipids ratios induced by a high-carbohydrate and low-fat diet in healthy youth

BACKGROUND: Diets are the important players in regulating plasma lipid profiles. And the R219K polymorphism at the gene of ATP-binding cassette transporter 1(ABCA1) was reported to be associated with the profiles. However, no efforts have been made to investigate the changes of lipid profiles after a high-carbohydrate and low-fat diet in different subjects with different genotypes of this polymorphism. This study was to evaluate the effects of ABCA1 R219K polymorphism on serum lipid and apolipoprotein (apo) ratios induced by a high-carbohydrate/low-fat (high-CHO) diet. After a washout diet of 54.1% carbohydrate for 7 days, 56 healthy young subjects (22.89 ± 1.80 years old) were given a high-CHO diet of 70.1% carbohydrate for 6 days. Height, weight, waist circumference, hip circumference, glucose (Glu), triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), apoA-1 and apoB-100 were measured on the 1st, 8th and 14th days of this study. Body mass index (BMI), waist-to-hip ratios (WHR), log(TG/HDL-C), TC/HDL-C, LDL-C/HDL-C and apoA-1/apoB-100 were calculated. ABCA1 R219K was analyzed by a PCR-RFLP method. RESULTS: The results indicate that the male subjects of all the genotypes had higher WHR than their female counterparts on the 1st, 8th and 14th days of this study. The male K carriers had higher log(TG/HDL-C) and TC/HDL-C than the female carriers on the 1st and 14th days, and higher LDL-C/HDL-C on the 14th day. When compared with that on the 8th day, TC/HDL-C was decreased regardless of the genotypes and genders on the 14th day. Log(TG/HDL-C) was increased in the males with the RR genotype and the female K carriers. Lowered BMI, Glu and LDL-C/HDL-C were found in the male K carriers, but only lowered BMI in the female K carriers and only lowered LDL-C/HDL-C in the females with the RR genotype. CONCLUSIONS: These results suggest that ABCA1 R219K polymorphism is associated differently in males and females with elevated log(TG/HDL-C) and decreased LDL-C/HDL-C induced by the high-CHO diet.

A high-carbohydrate diet enhances the adverse effect of the S2 allele of APOC3 SstI polymorphism on the TG/HDL-C ratio only in young Chinese females

Both genetic background and diet have profound effects on plasma lipid profiles. We hypothesized that a high-carbohydrate (high-CHO) diet may affect the ratios of serum lipids and apolipoproteins (apo) differently in subjects with different genotypes of the SstI polymorphism in the apoCIII gene (APOC3). Fifty-six healthy university students (27 males and 29 females, 22.89 ± 1.80 years) were given a washout diet of 54 percent carbohydrate for 7 days, followed by a high-CHO diet of 70 percent carbohydrate for 6 days without total energy restriction. Serum triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apoB100, apoAI, and the APOC3 SstI polymorphism were analyzed. The ratios of serum lipids and apoB100/apoAI were calculated. At baseline, the TG/HDL-C ratio was significantly higher in females, but not in males, with the S2 allele. The differences in the TG/HDL-C ratio between genotypes remained the same after the washout and the high-CHO diet in females. When compared with those before the high-CHO diet, the TC/HDL-C (male S2 carriers: 3.13 ± 1.00 vs 2.36 ± 0.65, P = 0.000; male subjects with the S1S1 genotype: 2.97 ± 0.74 vs 2.09 ± 0.55, P = 0.000; female S2 carriers: 2.68 ± 0.36 vs 2.24 ± 0.37, P = 0.004; female subjects with the S1S1 genotype: 2.69 ± 0.41 vs 2.09 ± 0.31, P = 0.000) and LDL-C/HDL-C (male S2 carriers: 1.44 ± 0.71 vs 1.06 ± 0.26, P = 0.012; male subjects with the S1S1 genotype: 1.35 ± 0.61 vs 1.01 ± 0.29, P = 0.005; female S2 carriers: 1.18 ± 0.33 vs 1.00 ± 0.18, P = 0.049; female subjects with the S1S1 genotype: 1.18 ± 0.35 vs 1.04 ± 0.19, P = 0.026) ratios were significantly decreased after the high-CHO diet regardless of gender and of genotype of the APOC3 SstI polymorphism. However, in female S2 carriers, the TG/HDL-C (1.38 ± 0.46 vs 1.63 ± 0.70, P = 0.039) ratio was significantly increased after the high-CHO diet. In conclusion, the high-CHO diet has favorable effects on the TC/HDL-C and LDL-C/HDL-C ratios regardless of gender and of genotype of the APOC3 SstI polymorphism. Somehow, it enhanced the adverse effect of the S2 allele on the TG/HDL-C ratio only in females.

A high-carbohydrate diet enhances the adverse effect of the S2 allele of APOC3 SstI polymorphism on the TG/HDL-C ratio only in young Chinese females.

Both genetic background and diet have profound effects on plasma lipid profiles. We hypothesized that a high-carbohydrate (high-CHO) diet may affect the ratios of serum lipids and apolipoproteins (apo) differently in subjects with different genotypes of the SstI polymorphism in the apoCIII gene (APOC3). Fifty-six healthy university students (27 males and 29 females, 22.89 ± 1.80 years) were given a washout diet of 54% carbohydrate for 7 days, followed by a high-CHO diet of 70% carbohydrate for 6 days without total energy restriction. Serum triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apoB100, apoAI, and the APOC3 SstI polymorphism were analyzed. The ratios of serum lipids and apoB100/apoAI were calculated. At baseline, the TG/HDL-C ratio was significantly higher in females, but not in males, with the S2 allele. The differences in the TG/HDL-C ratio between genotypes remained the same after the washout and the high-CHO diet in females. When compared with those before the high-CHO diet, the TC/HDL-C (male S2 carriers: 3.13 ± 1.00 vs 2.36 ± 0.65, P = 0.000; male subjects with the S1S1 genotype: 2.97 ± 0.74 vs 2.09 ± 0.55, P = 0.000; female S2 carriers: 2.68 ± 0.36 vs 2.24 ± 0.37, P = 0.004; female subjects with the S1S1 genotype: 2.69 ± 0.41 vs 2.09 ± 0.31, P = 0.000) and LDL-C/HDL-C (male S2 carriers: 1.44 ± 0.71 vs 1.06 ± 0.26, P = 0.012; male subjects with the S1S1 genotype: 1.35 ± 0.61 vs 1.01 ± 0.29, P = 0.005; female S2 carriers: 1.18 ± 0.33 vs 1.00 ± 0.18, P = 0.049; female subjects with the S1S1 genotype: 1.18 ± 0.35 vs 1.04 ± 0.19, P = 0.026) ratios were significantly decreased after the high-CHO diet regardless of gender and of genotype of the APOC3 SstI polymorphism. However, in female S2 carriers, the TG/HDL-C (1.38 ± 0.46 vs 1.63 ± 0.70, P = 0.039) ratio was significantly increased after the high-CHO diet. In conclusion, the high-CHO diet has favorable effects on the TC/HDL-C and LDL-C/HDL-C ratios regardless of gender and of genotype of the APOC3 SstI polymorphism. Somehow, it enhanced the adverse effect of the S2 allele on the TG/HDL-C ratio only in females.