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BACKGROUND: Diesel exhaust particles (DEPs), a predominant component of ambient particulate matter (PM), are classified as ultrafine particles with the capacity to penetrate the cerebral blood-brain barrier (BBB). This penetration is implicated in the pathogenesis of central nervous system (CNS) disorders. The integrity of the BBB is inextricably linked to cerebrovascular homeostasis and the development of neurodegenerative disease, highlighting the importance of studying the effects and mechanisms of DEPs on BBB function damage. METHODS AND RESULTS: Utilizing mouse cerebral microvascular endothelial cells (bEnd.3 cells) as an in vitro model of the BBB, we explored the detrimental effects of DEPs exposure on BBB permeability and integrity, with particular focus on inflammation, cell apoptosis, and miRNA expression profiles. Our findings revealed that exposure to DEPs at varying concentrations for 48â¯h resulted in the inhibition of bEND.3 cell proliferation, induction of cell apoptosis, and an upregulation in the secretion of inflammatory cytokines/chemokines and adhesion molecules. The BBB integrity was further compromised, as evidenced by a decrease in trans-epithelial electrical resistance(TEER), a reduction in cytoskeletal F-actin, , and diminished tight junction (TJ) protein expression. Microarray analysis revealed that 23 miRNAs were upregulated and 11 were downregulated in response to a 50⯵g/mL DEPs treatment, with miR-466d-3p being notably differentially expressed. Wnt3 was identified as a target of miR-466d-3p, with the Wnt signaling pathway being significantly enriched. We validated that miR-466d-3p expression was downregulated, and the protein expression levels of Wnt/ß-catenin and Wnt/PCP signaling components were elevated. The modulation of the Wnt signaling pathway by miR-466d-3p was demonstrated by the transfection of miR-466d-3p mimic, which resulted in a downregulation of Wnt3 and ß-catenin protein expression, and the mRNA level of Daam1, as well as an enhancement of TJ proteins ZO-1 and Claudin-5 expression. CONCLUSIONS: Our study further confirmed that DEPs can induce the disruption of BBB integrity through inflammatory processes. We identified alterations in the expression profile of microRNAs (miRNAs) in endothelial cells, with miR-466d-3p emerging as a key regulator of tight junction (TJ) proteins, essential for maintaining BBB integrity. Additionally, our findings primarily demonstrated that the Wnt/ ß-catenin and Wnt/PCP signaling pathway can be activated by DEPs and are regulated by miR-466d-3p. Under the combined effects of Wnt/PCP and inflammation, there is an ultimate increase in BBB hyperpermeability. METHODS AND RESULTS: Employing mouse cerebral microvascular endothelial cells (bEnd.3 cells) as an in vitro model of the BBB, we investigated the adverse effects of DEPs exposure on BBB permeability and integrity, with particular focus on inflammation, cell apoptosis, and miRNA expression profiles. Our findings revealed that exposure to DEPs at varying concentrations for 48â¯h resulted in the inhibition of bEND.3 cell proliferation, induction of cell apoptosis, and an increase in the release of inflammatory cytokines/chemokines and adhesion molecules. The BBB integrity was further compromised, as evidenced by a decrease in trans-epithelial electrical resistance(TEER), a reduction in cytoskeletal F-actin, loss of intercellular junctional organization, and diminished tight junction (TJ) protein expression. Microarray analysis disclosed that 23 miRNAs were upregulated and 11 were downregulated in bEND.3 cells treated with 50⯵g/mL DEPs compared to the controls. In particular, miR-466d-3p was identified as a significantly differentially expressed miRNA. Wnt3 was predicted to be a target of miR-466d-3p, and the Wnt signaling pathway was identified as one of the most significantly enriched pathways. We validated that miR-466d-3p expression was downregulated, and the protein expression levels of Wnt/ß-catenin and Wnt/PCP signaling components were elevated. The modulation of the Wnt signaling pathway by miR-466d-3p was demonstrated by the transfection of miR-466d-3p mimic, which resulted in a downregulation of Wnt3 and ß-catenin protein expression, and the mRNA level of Daam1, as well as an enhancement of TJ proteins ZO-1 and Claudin-5 expression. CONCLUSIONS: Our study further confirmed that DEPs can induce the disruption of BBB integrity by inflammation. We identified changes in the expression profile of microRNAs (miRNAs) in endothelial cells, with miR-466d-3p emerging as a regulator of tight junction (TJ) proteins, which are critical for maintaining BBB integrity. Additionally, our findings primarily demonstrated that the Wnt/ ß-catenin and Wnt/PCP signaling pathway can be activated by DEPs and is regulated by miR-466d-3p, and under the combined effects of Wnt/PCP and inflammation ultimately led to hyperpermeability BBB.
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Scientific fertilization is an important technical means of achieving high and stable peanut yields. Using soil testing and formula fertilization, the "3414" optimal regression design was used and included 14 nitrogen (N), phosphorus (P), and potassium (K) fertilization treatments. Ternary quadratic functions of the fertilizer effect were established according to three-season field experiments and the regression analysis of fertilizer-yield function was performed to explore the optimal fertilizer application mode and ratio for peanuts under mulched drip irrigation (MDI), and a suitable fertilizer application system was established. The ternary quadratic equation relating peanut yield (y) and the fertilizer application rates of N (N), P (P2O5), and K (K2O) was obtained after fitting, i.e., y = 2912.528 + 21.432N + 16.324P + 6.181K - 0.051N2 - 0.109P2 - 0.061K2 + 0.017NP + 0.023NK + 0.086PK, and significance analysis and typicality assessment were performed. The model R 2 was 0.9709, both values are extremely significant (p < 0.01), which indicates that the obtained ternary quadratic fertilizer effect function is typical and could be used for statistical purposes and fertilization recommendations. Three quadratic fertilizer effect functions were obtained. Among them, the equation for K is extremely significant, and the equations of N and P are significant. According to the assumption that the marginal yield is zero and the marginal profit is zero, the fertilizer application rate with the maximum yield, the fertilizer application rate with the best economic benefits, and the corresponding yields were obtained. The optimal fertilizer application rate predicted by the ternary quadratic fertilizer effect function was relatively high, so the three quadratic fertilizer effect functions were used for prediction. Under the test conditions, the recommended fertilizer application rates for peanuts under MDI are 256.6 kg N per ha, 164.2 kg P2O5 per ha, and 213.2 kg K2O per ha, the recommended fertilization ratio is 1:0.64:0.83, and the recommended ratio under formula fertilization is 23:15:19. The study has developed a data-based decision support system for Xinjiang drip-irrigated peanut, which assists farmers and agricultural managers in making more scientific and precise fertilization decisions based on the specific growth requirements of the crops and soil conditions. This evidence-based methodology enhances the precision of agricultural management, which is conducive to increasing crop yields while reducing resource wastage and environmental impact. However, multipoint and multiyear experiments are still needed to ensure that the findings are adaptable to the diverse soil conditions and fluctuating climate patterns that may be encountered in practice.
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Considering the pear in the arid region as the research object, single-factor testing and water-fertilizer coupling testing were conducted. The response of pear tree growth to water, nitrogen, and phosphorus was explored and provided a theoretical basis for efficient water and fertilizer management. Among them, the single-factor test set water, nitrogen, and phosphorus as the three factors, and five levels were set. Screening out W3, W4, N3, N4, P3, and P4 promoted plant nutrient uptake and fruit quality. Eight treatments were set up in the water and fertilizer coupling test: Treatment 1 (T1, W3N3P3), Treatment 2 (T2, W3N3P4), Treatment 3 (T3, W3N4P3), Treatment 4 (T4, W3N4P4), Treatment 5 (T5, W4N3P3), Treatment 6 (T6, W4N3P4), Treatment 7 (T7, W4N4P3), and Treatment 8 (T8, W4N4P4). The results showed that the leaf area index of the T1, T2, T3, and T4 treatments was significantly higher than that of the other treatments at maturity. The yield, single fruit weight, and primary fruit rate were the highest under T3 treatment. The gray correlation degree analysis of fruit quality showed that the T3 treatment had the highest degree of correlation and ranking of each fruit quality index, indicating that the T3 treatment had the highest fruit quality. The yield model showed that irrigation with 6510.06 m3 hm-2, nitrogen fertilizer with 337.5 kg N hm-2, and phosphate fertilizer with 262.5 kg P hm-2 had the best yield. A detailed investigation of pear tree growth and fruit quality showed that the T3 treatment had the best fruit growth and development performance, and the pear fruit quality was the best.
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This work investigates the impact of pressure on the structural, optical properties, and electronic structure of CsPbBr3 quantum dots (QDs) using steady-state photoluminescence, steady-state absorption, and femtosecond transient absorption spectroscopy, reaching a maximum pressure of 3.38 GPa. The experimental results indicate that CsPbBr3 QDs undergo electronic state (ES) transitions from ES-I to ES-II and ES-II to ES-III at 0.38 and 1.08 GPa, respectively. Intriguingly, a mixed state of ES-II and ES-III is observed within the pressure range of 1.08-1.68 GPa. The pressure-induced fluorescence quenching in ES-II is attributed to enhanced defect trapping and reduced radiative recombination. Above 1.68 GPa, fluorescence vanishes entirely, attributed to the complete phase transformation from ES-II to ES-III in which radiative recombination becomes non-existent. Notably, owing to stronger quantum confinement effects, CsPbBr3 QDs exhibit an impressive bandgap tuning range of 0.497 eV from 0 to 2.08 GPa, outperforming nanocrystals by 1.4 times and bulk counterparts by 11.3 times. Furthermore, this work analyzes various carrier dynamics processes in the pressure-induced bandgap evolution and electron state transitions, and systematically studies the microphysical mechanisms of optical properties in CsPbBr3 QDs under pressure, offering insights for optimizing optical properties and designing novel materials.
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Plum (Prunus spp.) is an economically and nutritionally important stone fruit that is grown worldwide. Gummosis disease (GD) is one of the most common limiting factors that adversely affects the yield and quality of stone fruits such as plum. Elucidating plum fruit metabolomics responses is essential to develop sustainable agricultural practices to combat GD in the future. Herein, an ultra-high-performance liquid chromatography coupled to mass-spectrometry (UHPLC-MS) pseudo-targeted metabolomic profiling was first performed to elucidate the overall metabolic alterations in Asian plum (Prunus salicina Lindl.) fruit in response to GD. The most pivotal differential metabolites, including certain amino acids and proanthocyanidins, in GD and control groups were identified by combining multivariate data analysis with strict statistical criteria. Metabolic pathway enrichment analysis showed that GD induced a series of coordinated defence responses and reprogramming of various metabolic pathways, including glucosinolate biosynthesis, 2-oxocarboxylic acid metabolism, valine, leucine and isoleucine degradation, and isoquinoline alkaloid biosynthesis pathways. Using UHPLC-MS-based pseudo-targeted metabolomic profiling, we systematically evaluated overall metabolic modifications in Asian plum fruits in response to GD for the first time. The identified metabolic pathway alterations helped to better understand the internal relationships and related metabolic networks.
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Alcaloides , Proantocianidinas , Prunus domestica , Alcaloides/análisis , Cromatografía Líquida de Alta Presión , Frutas/química , Glucosinolatos/análisis , Isoleucina/análisis , Isoquinolinas/análisis , Leucina/análisis , Espectrometría de Masas , Redes y Vías Metabólicas , Proantocianidinas/análisis , Prunus domestica/metabolismo , Valina/análisisRESUMEN
Carrizo citrange [Citrus sinensis (L.) Osbeck × Poncirus trifoliata (L.) Raf., CC] is one of the most widely used rootstocks in citriculture worldwide, but its cytogenetic study has been hampered by its inherent small size, morphological similarity to mitotic chromosomes, and lack of accessible cytological landmarks. In our previous study, a spontaneously occurring tetraploid CC seedling was discovered. The main goals of this study were to elucidate the chromosome constitution and construct the karyotypes of diploid CC rootstock and its corresponding spontaneously occurring tetraploid. To accomplish these, the chromosomal characteristics were investigated by sequential multicolor fluorescence in situ hybridization (FISH) with eight properly labeled repetitive DNA sequences, including a centromere-like repeat, four satellite repeats, two rDNAs, and an oligonucleotide of telomeric (TTTAGGG) n repeat. The results nicely demonstrated that these repetitive DNAs are reliable cytogenetic markers that collectively facilitate simultaneous and unequivocal identification of homologous chromosome pairs. Based on chromosome size and morphology together with FISH patterns of repetitive DNAs, an integrated karyotype of CC rootstock was constructed, consisting of 2n = 2x = 12m (1sat) + 6sm with karyotype asymmetry degree being divided into 2B category. Cytogenetically speaking, the variable and asymmetric distribution patterns of these repetitive DNAs were fully confirmed the hybrid nature of CC rootstock. In addition, comparative distribution patterns and chromosomal localizations of these repetitive DNAs convincingly showed that this tetraploid CC material arose from somatic chromosome doubling of diploid CC rootstock. This study revealed, for the first time, the integrated karyotype and chromosomal characteristics of this important citrus rootstock as well as its spontaneously occurring tetraploid plant. Furthermore, this study is a good prospective model for study species with morphologically indistinguishable small chromosomes.
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Dibromoacetic acid (DBA) is one of haloacetic acids, often as a by-product of disinfection in drinking water. DBA is a multiple-organ carcinogen in rodent animals, but little research on its hepatotoxicity has been conducted and its mechanism has not been elucidated. In this study, we found that DBA could induce obvious hepatotoxcity in Balb/c mice as indicated by histological changes, increasing serum level of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and accumulation of hepatic glycogen, after the mice were administered DBA at doses of 1.25, 5, and 20 mg/kg body weight for 28 days via oral gavage. In mechanism study, DBA induced oxidative stress as evidenced by increasing the level of malondialdehyde (MDA), reactive oxygen species (ROS) in the liver, advanced oxidative protein products (AOPPs) in the serum, and decreasing the level of glutathione (GSH) in the liver. DBA induced inflammation in the liver of the mice which is supported by increasing the production of tumor necrosis factor-α (TNF-α) and the mRNA levels of TNF-α, interleukin-6 (IL-6), interleukin-1ß (IL-1ß), and nuclear factor κB (NF-κB) in the liver. DBA also upregulated the protein levels of Toll-like receptor (TLR) 4, myeloid differentiation factor 88 (MyD88), tumor necrosis factor receptor-associated factor 6 (TRAF6), inhibitor of nuclear factor κB alpha (IκB-α), nuclear factor κB p65 (NF-κB p65), and the phosphoralation of P38 mitogen-activated protein kinase (P38MAPK) and c-Jun N-terminal kinase (JNK). Conclusion. DBA could induce hepatotoxicity in mice by oral exposure; the mechanism is related to oxidative stress, inflammation, and Toll-like receptor 4 signaling pathway activation.
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Acetatos/toxicidad , Hígado/metabolismo , Estrés Oxidativo/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Administración Oral , Animales , Peso Corporal/efectos de los fármacos , Glutatión/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Hígado/efectos de los fármacos , Hígado/ultraestructura , Ratones , Ratones Endogámicos BALB C , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo , Inhibidor NF-kappaB alfa/genética , Inhibidor NF-kappaB alfa/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Receptor Toll-Like 4/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
In this study, a semi-open-top artificial climate chamber was used to study the effect of CO2 enrichment (360 and 540 µmol · mol(-1)) and nitrogen addition (0, 150, 300 and 450 kg · hm(-2)) on cotton dry matter accumulation and distribution, nitrogen absorption and soil urease activity. The results showed that the dry matter accumulation of bud, stem, leaf and the whole plant increased significantly in the higher CO2 concentration treatment irrespective of nitrogen level. The dry matter of all the detected parts of plant with 300 kg · hm(-2) nitrogen addition was significantly higher than those with the other nitrogen levels irrespective of CO2 concentration, indicating reasonable nitrogen fertilization could significantly improve cotton dry matter accumulation. Elevated CO2 concentration had significant impact on the nitrogen absorption contents of cotton bud and stem. Compared to those under CO2 concentration of 360 µmol · mol(-1), the nitrogen contents of bud and stem both increased significantly under CO2 concentration of 540 µmol · mol(-1). The nitrogen content of cotton bud in the treatment of 300 kg · hm(-2) nitrogen was the highest among the four nitrogen fertilizer treatments. While the nitrogen contents of cotton stem in the treatments of 150 kg · hm(-2) and 300 kg · hm(-2) nitrogen levels were higher than those in the treatment of 0 kg · hm(-2) and 450 kg · hm(-2) nitrogen levels. The nitrogen content of cotton leaf was significantly influenced by the in- teraction of CO2 elevation and N addition as the nitrogen content of leaf increased in the treatments of 0, 150 and 300 kg · hm(-2) nitrogen levels under the CO2 concentration of 540 µmol · mol(-1). The nitrogen content in cotton root was significantly increased with the increase of nitrogen fertilizer level under elevated CO2 (540 µmol · mol(-1)) treatment. Overall, the cotton nitrogen absorption content under the elevated CO2 (540 µmol · mol(-1)) treatment was higher than that under the ambient CO2- (360 µmol · mol(-1)) treatment. The order of nitrogen accumulation content in organs was bud > leaf > stem > root. Soil urease activity of both layers increased significantly with the elevation of CO2 concentration in all the nitrogen treatments. Under each CO2 concentration treatment, the soil urease activity in the upper layer (0-20 cm) increased significantly with nitrogen application, while the urease activity under the application of 300 kg · hm(-2) nitrogen was highest in the lower layer (20- 40 cm). The average soil urease activity in the upper layer (0-20 cm) was significantly higher than that in the lower layer (20-40 cm). This study suggested that the cotton dry matter accumulation and nitrogen absorption content were significantly increased in response to the elevated CO2 concentration (540 µmol · mol(-1)) and higher nitrogen addition (300 kg · hm(-2)).
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Dióxido de Carbono/química , Fertilizantes , Gossypium/crecimiento & desarrollo , Nitrógeno/química , Suelo/química , Ureasa/química , Biomasa , Clima , Hojas de la Planta/crecimiento & desarrollo , Raíces de Plantas/crecimiento & desarrollo , Tallos de la Planta/crecimiento & desarrolloRESUMEN
Clostridium perfringens enterotoxin (CPE) causes the symptoms associated with several common gastrointestinal diseases. CPE is a 35 kDa polypeptide consisting of three structured domains, that is, C-terminal domain I (responsible for receptor binding), domain II (responsible for oligomerization and membrane insertion), and domain III (which may participate in physical changes when the CPE protein inserts into membranes). Native CPE binds to claudin receptors, which are components of the tight junction. The bound toxin then assembles into a hexameric prepore on the membrane surface, prior to the insertion of this oligomer into membranes to form an active pore. The toxin is especially lethal for cells expressing large amounts of claudin-3 or -4, which includes many cancer cells. Initial studies suggest that native CPE has potential usefulness for treating several cancers where claudin CPE receptors are overexpressed. However, some challenges with immunogenicity, toxicity, and (possibly) the development of resistance may need to be overcome. An alternative approach now being explored is to utilize C-CPE, which corresponds approximately to receptor binding domain I, to enhance paracellular permeability and delivery of chemotherapeutic agents against cancer cells. Alternatively, C-CPE fusion proteins may prove superior to use of native CPE for cancer treatment. Finally, C-CPE may have application for other medical treatments, including vaccination or increasing drug absorption. The coming years should witness increasing exploitation of this otherwise formidable toxin.
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Laser welding has the potential to become an effective method for wound closure and healing without sutures. Closure of skin incisions by laser welding with a combination of two near-infrared lasers (980 and 1064 nm), was performed for the first time in this study. One centimeter long, full-thickness incisions were made on the Wistar rat's dorsal skin. The efficiencies of laser-welding with different parameters were investigated. Incision-healing, histology examination, and a tensile strength test of incisions were recorded. Laser welding with the irradiance level of 15.9 W∕cm(2) for both 980 and 1064-nm lasers and exposure time of 5 s per spot in continuous wave mode yielded a more effective closure and healing with minimal thermal damage, faster recovery, and stronger apposition in comparison with a suturing technique. The conclusion is that skin welding with a combination of two near-infrared diode lasers can be a good candidate for incision closure, and further investigations are in progress for clinical use.
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Procedimientos Quirúrgicos Dermatologicos , Láseres de Semiconductores/uso terapéutico , Técnicas de Cierre de Heridas , Animales , Masculino , Fenómenos Ópticos , Ratas , Ratas Wistar , Piel/patología , Piel/fisiopatología , Técnicas de Sutura , Resistencia a la Tracción , Cicatrización de HeridasRESUMEN
PURPOSE: We have previously shown that CLDN4 (encoding claudin-4), a cell tight junction (TJ) protein, is highly expressed in human epithelial ovarian carcinomas (EOC) but undetectable in normal ovaries. CLDN4 has been identified as a specific receptor for C terminus of Clostridium perfringens enterotoxin (C-CPE), a nontoxic molecule that may disrupt TJ barrier function and enhance cellular absorption. The purpose of this study was to determine the potential clinical applications of C-CPE and its effects on CLDN4 expression in EOC. EXPERIMENTAL DESIGN: Using a 3-dimensional culture model and monolayer culture of EOC cells, we examined the effects of C-CPE on CLDN4 expression by quantitative real-time PCR, immunofluorescence, and Western blot. The synergistic effect of C-CPE to clinically relevant chemotherapies (Taxol and Carboplatin) was observed in EOC culture and xenograft mice. Furthermore, we determined through oligonucleotide microarray analysis that the transcript profile alterations dysregulated as a consequence of C-CPE treatment. RESULTS: C-CPE treatment decreased protein expression and relocated CLDN4 from cell-cell contact regions to the cytoplasm. Particularly, C-CPE sensitized EOC cells to chemotherapeutic administration at low dosages and significantly inhibited tumor growth in a nontoxic manner. Furthermore, we provided genome-wide molecular evidence that C-CPE treatment is involved in the stimulation of the ubiquitin-proteasome pathway and the inhibition of cell metabolism in EOC cells. CONCLUSIONS: The addition of C-CPE can enhance the effectiveness of Taxol or Carboplatin and significantly inhibited EOC cell growth in a CLDN4-dependent manner, suggesting that C-CPE may have promising therapeutic potential for EOC.
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Antineoplásicos/uso terapéutico , Carboplatino/uso terapéutico , Enterotoxinas/uso terapéutico , Proteínas de la Membrana/genética , Neoplasias Glandulares y Epiteliales/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Paclitaxel/uso terapéutico , Animales , Antineoplásicos/farmacología , Western Blotting , Carboplatino/farmacología , Carcinoma Epitelial de Ovario , Células Cultivadas , Claudina-4 , Clostridium perfringens/metabolismo , Células Epiteliales/metabolismo , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Etiquetado Corte-Fin in Situ , Proteínas de la Membrana/metabolismo , Ratones , Ratones SCID , Neoplasias Glandulares y Epiteliales/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Neoplasias Ováricas/metabolismo , Paclitaxel/farmacología , Reacción en Cadena de la Polimerasa , Complejo de la Endopetidasa Proteasomal/metabolismo , ARN Mensajero/análisis , Uniones Estrechas , Complejos de Ubiquitina-Proteína Ligasa/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Claudin-4, a tight junction (TJ) protein and receptor for the C-terminal fragment of Clostridium perfringens enterotoxin (C-CPE), is overexpressed in epithelial ovarian cancer (EOC). Previous research suggests DNA methylation is a mechanism for claudin-4 overexpression in cancer and that C-CPE acts as an absorption-enhancing agent in claudin-4-expressing cells. We sought to correlate claudin-4 overexpression in EOC with clinical outcomes and TJ barrier function, investigate DNA methylation as a mechanism for overexpression, and evaluate the effect of C-CPE on the TJ. METHODS: Claudin-4 expression in EOC was quantified and correlated with clinical outcomes. Claudin-4 methylation status was determined, and claudin-4-negative cell lines were treated with a demethylating agent. Electric cell-substrate impedance sensing was used to calculate junctional (paracellular) resistance (Rb) in EOC cells after claudin-4 silencing and after C-CPE treatment. RESULTS: Claudin-4 overexpression in EOC does not correlate with survival or other clinical endpoints and is associated with hypomethylation. Claudin-4 overexpression correlates with Rb and C-CPE treatment of EOC cells significantly decreased Rb in a dose- and claudin-4-dependent noncytotoxic manner. CONCLUSIONS: C-CPE treatment of EOC cells leads to altered TJ function. Further research is needed to determine the potential clinical applications of C-CPE in EOC drug delivery strategies.
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Clostridium perfringens/fisiología , Metilación de ADN , Enterotoxinas/administración & dosificación , Proteínas de la Membrana/genética , Neoplasias Glandulares y Epiteliales/metabolismo , Neoplasias Ováricas/metabolismo , Fragmentos de Péptidos/administración & dosificación , Uniones Estrechas/enzimología , Uniones Estrechas/fisiología , Línea Celular Tumoral , Claudina-4 , Metilación de ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Sistemas de Liberación de Medicamentos/métodos , Enterotoxinas/toxicidad , Femenino , Humanos , Proteínas de la Membrana/biosíntesis , Neoplasias Glandulares y Epiteliales/tratamiento farmacológico , Neoplasias Glandulares y Epiteliales/genética , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Fragmentos de Péptidos/toxicidad , Uniones Estrechas/efectos de los fármacosRESUMEN
It is now evident that the use of levonorgestrel-releasing intrauterine system (LNg-IUS) is effective for long-term management of menorrhagic women with uterine myomas because of a striking reduction in menorrhagia. This prompted us to characterize the effects of progesterone (P4) on the growth and apoptosis of uterine leiomyoma cells. On the other hand, we have recently noted that epidermal growth factor (EGF) and IGF-I play a crucial role in prompting uterine leiomyoma growth through stimulating the proliferative potential and inhibiting apoptosis of cultured human leiomyoma cells. In the present review, attention was paid to evaluate the effects of P4 on the expression of growth factors (EGF, IGF-I) and apoptosis-related factors (TNFalpha, Bcl-2 protein) in cultured uterine leiomyoma cells. Treatment with P4 augmented EGF and Bcl-2 protein expression, but inhibited IGF-I and TNFalpha expression in cultured leiomyoma cells. It is known that TNFalpha induces apoptosis in a variety of cell types and Bcl-2 protein is an apoptosis-inhibiting gene product. Thus, the results obtained suggest that P4 has dual actions on uterine leiomyoma growth: one is to stimulate leiomyoma cell growth and survival through up-regulating EGF and Bcl-2 protein expression as well as down-regulating TNFalpha expression in those cells, and the other is to inhibit leiomyoma cell growth through down-regulating IGF-I expression in those cells. This may explain why the size of uterine myomas during use of LNg-IUS increases in some but decreases in other instances. This may also explain why the size of uterine myomas during pregnancy does not increase despite the overwhelming increase in circulating concentrations of sex steroid hormones.
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Sustancias de Crecimiento/biosíntesis , Leiomioma/metabolismo , Progesterona/fisiología , Neoplasias Uterinas/metabolismo , Apoptosis , Western Blotting , División Celular , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo , Factor de Crecimiento Epidérmico/metabolismo , Femenino , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Regulación hacia ArribaRESUMEN
p53 protein, a tumor suppressor gene product, has been reported to play a crucial role in suppressing the growth of a variety of cancer cells. However, little information is currently available regarding the content of p53 protein in human leiomyomas. The present study was conducted to elucidate the p53 protein content in human leiomyomas and its regulation by sex steroid hormones. The content of p53 protein in leiomyomas was examined by immunohistochemical staining and Western blot analysis in comparison with that in the adjacent normal myometrium or leiomyoma specimens from GnRH agonist-treated patients. In addition, isolated human leiomyoma cells were subcultured in phenol red-free DMEM supplemented with 10% FBS for 120 h and then stepped down to serum-free conditions for an additional 72 h in the absence or presence of 17 beta-estradiol (E2; 10 ng/ml), progesterone (P4; 100 ng/ml), or E2 (10 ng/ml) plus P4 (100 ng/ml). The effects of sex steroids on p53 protein content in cultured leiomyoma cells were also assessed by Western immunoblot analysis. Immunohistochemical staining and Western blot analysis revealed that p53 protein content was highest in leiomyomas treated with GnRH agonist for 16 wk, lower in leiomyomas in the secretory, P4-dominated phase, and lowest in leiomyomas in the proliferative, E2-dominated phase of the menstrual cycle. There was no difference in p53 content between leiomyomas and the adjacent normal myometrium. Western blot analysis of cultured leiomyoma cell extracts revealed that E2 treatment significantly decreased p53 protein content compared with the control cultures, whereas either P4 treatment or combined treatment with E2 and P4 did not affect p53 protein content in cultured leiomyoma cells. The concentrations of sex steroid hormones used were within the physiological tissue concentrations in leiomyomas and myometrium described earlier. The present study suggests that E2 down-regulates p53 protein content, whereas P4 is ineffective in those cells. The E2-induced decrease in p53 protein content in leiomyoma cells leads us to propose that E2 may regulate human leiomyoma growth in part by down-regulating p53 tumor suppressor protein content in those cells.