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KEY MESSAGE: The interaction network and pathway map uncover the potential crosstalk between sugar and hormone metabolisms as a possible reason for leaf senescence in P. ternata. Pinellia ternata, an environmentally sensitive medicinal plant, undergoes leaf senescence twice a year, affecting its development and yield. Understanding the potential mechanism that delays leaf senescence could theoretically decrease yield losses. In this study, a typical senescent population model was constructed, and an integrated analysis of transcriptomic and metabolomic profiles of P. ternata was conducted using two early leaf senescence populations and two stay-green populations. The result showed that two key gene modules were associated with leaf senescence which were mainly enriched in sugar and hormone signaling pathways, respectively. A network constructed by unigenes and metabolisms related to the obtained two pathways revealed that several compounds such as D-arabitol and 2MeScZR have a higher significance ranking. In addition, a total of 130 hub genes in this network were categorized into 3 classes based on connectivity. Among them, 34 hub genes were further analyzed through a pathway map, the potential crosstalk between sugar and hormone metabolisms might be an underlying reason of leaf senescence in P. ternata. These findings address the knowledge gap regarding leaf senescence in P. ternata, providing candidate germplasms for molecular breeding and laying theoretical basis for the realization of finely regulated cultivation in future.
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Regulação da Expressão Gênica de Plantas , Metabolômica , Pinellia , Reguladores de Crescimento de Plantas , Folhas de Planta , Transcriptoma , Folhas de Planta/genética , Folhas de Planta/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Pinellia/genética , Pinellia/metabolismo , Pinellia/fisiologia , Pinellia/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/metabolismo , Transcriptoma/genética , Senescência Vegetal/genética , Perfilação da Expressão Gênica , Açúcares/metabolismo , Metaboloma/genética , Redes Reguladoras de Genes , Metabolismo dos Carboidratos/genéticaRESUMO
BACKGROUND: The presence of plasmid-mediated resistance-nodulation-division (RND) efflux pump gene cluster tmexCD1-toprJ1 and its related variants has been associated with heightened resistance to tigecycline, thus diminishing its effectiveness. In this study, we explored the potential of gramine, a naturally occurring indole alkaloid, as an innovative adjuvant to enhance the treatment of infections caused by K. pneumoniae carrying tmexCD-toprJ-like gene clusters. METHODS: The synergistic potential of gramine in combination with antibiotics against both planktonic and drug-tolerant multidrug-resistant Enterobacterales was evaluated using the checkerboard microbroth dilution technique and time-killing curve analyses. Afterwards, the proton motive force (PMF) of cell membrane, the function of efflux pump and the activity of antioxidant system were determined by fluorescence assay and RT-PCR. The intracellular accumulation of tigecycline was evaluated by HPLC-MS/MS. The respiration rate, bacterial ATP level and the NAD+/NADH ratio were investigated to reveal the metabolism state. Finally, the safety of gramine was assessed through hemolytic activity and cytotoxicity assays. Two animal infection models were used to evaluate the in vivo synergistic effect. RESULTS: Gramine significantly potentiated tigecycline and ciprofloxacin activity against tmexCD1-toprJ1 and its variants-positive pathogens. Importantly, the synergistic activity was also observed against bacteria in special physiological states such as biofilms and persister cells. The mechanism study showed that gramine possesses the capability to augment tigecycline accumulation within cells by disrupting the proton motive force (PMF) and inhibiting the efflux pump functionality. In addition, the bacterial respiration rate, intracellular ATP level and tricarboxylic acid cycle (TCA) were promoted under the treatment of gramine. Notably, gramine effectively restored tigecycline activity in multiple animal infection models infected by tmexCD1-toprJ1 positive K. pneumoniae (RGF105-1). CONCLUSION: This study provides the first evidence of gramine's therapeutic potential as a novel tigecycline adjuvant for treating infections caused by K. pneumoniae carrying tmexCD-toprJ-like gene clusters.
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Infecções por Klebsiella , Klebsiella pneumoniae , Animais , Tigeciclina/metabolismo , Tigeciclina/farmacologia , Tigeciclina/uso terapêutico , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo , Minociclina/farmacologia , Minociclina/metabolismo , Minociclina/uso terapêutico , Espectrometria de Massas em Tandem , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Farmacorresistência Bacteriana , Antibacterianos/farmacologia , Alcaloides Indólicos/farmacologia , Trifosfato de Adenosina/metabolismo , Testes de Sensibilidade MicrobianaRESUMO
Zanthoxylum bungeanum has a lengthy history of widespread use as a food ingredient in China. However, the composition of Zanthoxylum bungeanum polysaccharide remains ambiguous, and the antioxidant effect has received limited attention. This study aimed to extract water-soluble polysaccharide from the dried pericarp of Zanthoxylum bungeanum, referred to as WZBP, which was fractionated into a neutral component (WZBP-N) and three pectic components (WZBP-A-I, WZBP-A-II, WZBP-A-III). The findings indicated that WZBP-A-III is a pectic polysaccharide "smooth region" without many side chains. All components of WZBP exhibited a notable capacity for scavenging free radicals, with WZBP-A-III demonstrating the most potent antioxidation activity, and WZBP-A-III also observed to effectively extend the lifespan of Drosophila melanogaster and enhanced the activity of antioxidant enzymes. These results provide valuable insight and direction for future research on Zanthoxylum bungeanum polysaccharide as an antioxidant agent.
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Antioxidantes , Zanthoxylum , Animais , Zanthoxylum/química , Drosophila melanogaster , Polissacarídeos , PectinasRESUMO
Background: The relationship between vitamin E supplementation and the prevalence of chronic kidney disease (CKD) is unclear. We discussed the relationship between vitamin E intake and CKD prevalence and further investigated the effect on different CKD risk strata. Methods: We ultimately included 20 295 participants from the National Health and Nutrition Examination Survey (NHANES) database from 2009 to 2016. Multiple logistic regression and restricted cubic splines (RCS) were applied to explore the relationship between vitamin E intake and CKD prevalence and risk stratification. Subgroup analysis was applied to assess the stability of the association between vitamin E intake and CKD. Results: In the CKD prevalence study, we found a negative association between high vitamin E intake and CKD prevalence through an adjusted multiple logistic regression model, the odds ratio (OR) was 0.86 [95% confidence interval (CI) 0.74-1.00; P for trend = .041] and RCS showed a nonlinear negative correlation (P-nonlinear = .0002, <.05). In the CKD risk stratification study, we found that in very high-risk patients, the OR was 0.51 (95% CI 0.32-0.84; P for trend = .006) and the RCS also showed a nonlinear negative correlation (P-nonlinear <.0001, <.05). Subgroup analysis demonstrated that the correlations were stable across populations (P-values >.01 for all interactions). Conclusion: Dietary vitamin E intake was negatively associated with the prevalence of CKD in US adults. Increased vitamin E intake was a protective factor across CKD risk strata, and as vitamin E intake increased, there was a non-linear downward trend in the proportion progressing to very high-risk CKD.
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BACKGROUND: Guided bone regeneration (GBR) involves collecting bone autografts with high bio-quality and efficiency. The current non-irrigated low-speed drilling has been limited for broader application in bone autograft harvest due to its low efficiency, inability to conduct buccal cortical perforation, and dependence on simultaneous implant placement. Increasing the drilling speed helps improve the efficiency but may incur thermal-mechanical bone damage. Most studies have addressed thermal reactions during bone drilling on non-vital models, which is irrelevant to clinical scenarios. Little has been known about bone's in vivo thermal profiles under non-irrigated higher-speed drilling and its influences on the resulting bone chips. AIM: A novel technique for bone harvest and cortical perforation via in-situ non-irrigated higher-speed drilling was proposed and investigated for the first time. METHODS: The third mandible premolars of eight beagles were extracted and healed for three months. Sixteen partial edentulous sites (left and right) were randomized into four groups for bone autograft harvest without irrigation: chisel, 50 rpm drilling, 500 rpm drilling, and 1000 rpm drilling. Bone chips were harvested on the buccal plates of the missing tooth. An infrared camera and an implantable thermocouple collaboratively monitored in vivo real-time bone temperature at the drilling sites. In vitro performances of cells from bone chips, including cell number, viability, proliferation, migration, ALP activity, in vitro mineralization, mRNA transcriptional level of osteogenic genes and heat shock protein 70 (HSP-70), and HSP-70 expression at the protein level were also studied. RESULTS: 500 rpm produced mild local hyperthermia with a 2-6 °C temperature rise both on the cortical surface and inside the cortical bone. It also held comparable or enhanced cell performances such as cell number, viability, proliferation, migration, ALP activity, in vitro mineralization, and osteogenic genes expression. CONCLUSIONS: In-situ non-irrigated higher-speed drilling at 500 rpm using a screw drill is versatile, efficient, and thermal friendly and improves the bio-quality of bone chips. Our novel technique holds clinical translational potential in GBR application.
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Hipertermia Induzida , Osteotomia , Cães , Animais , Autoenxertos , Osteotomia/métodos , Osso e Ossos , Osteogênese , Temperatura AltaRESUMO
BACKGROUND: The emergence and wide spread of plasmid-mediated colistin resistance gene (mcr-1) and its mutants have immensely limited the efficacy of colistin in treating multidrug-resistant (MDR) Gram-negative bacterial infections. The development of synergistic combinations of antibiotics with a natural product that coped with the resistance of MDR bacteria was an economic strategy to restore antibiotics activity. Herein, we investigated gigantol, a bibenzyl phytocompound, for restoring in vitro and in vivo, the sensitivity of mcr-positive bacteria to colistin. METHODS: The synergistic activity of gigantol and colistin against multidrug-resistant Enterobacterales was studied via checkerboard assay and time-killing curve. Subsequently, the transcription and protein expression levels of mcr-1 gene were determined by RT-PCR and Western blots. The interaction of gigantol and MCR-1 was simulated via molecular docking and verified via site-directed mutagenesis of MCR-1. Hemolytic activity and cytotoxicity assay were used to evaluate the safety of gigantol. Finally, the in vivo synergistic effect was evaluated via two animal infection models. RESULTS: Gigantol restored the activity of colistin against mcr-positive bacteria E.coli B2 (MIC from 4 µg/ml to 0.25 µg/ml), Salmonella 15E343 (MIC from 8 µg/ml to 1 µg/ml), K. pneumoniae 19-2-1 (MIC from 32 µg/ml to 2 µg/ml) carrying mcr-1, mcr-3, mcr-8, respectively. Mechanistic studies revealed that gigantol down-regulated the expression of genes involved in LPS-modification, reduced the MCR-1 products and inhibited the activity of MCR-1 by binding to amino acid residues Tyr287 and Pro481 in its D-glucose-binding pocket. Safety evaluation showed that the addition of gigantol relieves the hemolysis caused by colistin. Compared with monotherapy, the combination of gigantol and colistin significantly improved the survival rate of Gallgallella mellonella larvae and mice infected by E.coli B2. Moreover, there was a considerable decrease in the bacterial load present in the viscera of mice. CONCLUSION: Our results confirmed that gigantol was a potential colistin adjuvant, and could be used to tackle multi-drug resistant Gram-negative pathogen infections combined with colistin.
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Bibenzilas , Proteínas de Escherichia coli , Animais , Camundongos , Colistina/farmacologia , Simulação de Acoplamento Molecular , Antibacterianos/farmacologia , Bibenzilas/farmacologia , Escherichia coli , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/farmacologia , PlasmídeosRESUMO
The octadentate hydroxypyridonate ligand 3,4,3-LI(1,2-HOPO) (t-HOPO) shows strong binding affinity with actinide cations and is considered as a promising decorporation agent used to eliminate in vivo actinides, while its dynamics in its unbound and bound states in the condensed phase remain unclear. In this work, by means of MD simulations, the folding dynamics of intact t-HOPO in its neutral (t-HOPO0) and in its deprotonated state (t-HOPO4-) were studied. The results indicated that the deprotonation of t-HOPO in the aqueous phase significantly narrowed the accessible conformational space under the simulated conditions, and it was prepared in a conformation that could conveniently clamp the cations. The simulation of UIV-t-HOPO showed that the tetravalent uranium ion was deca-coordinated with eight ligating O atoms from the t-HOPO4- ligand, and two from aqua ligands. The strong electrostatic interaction between the U4+ ion and t-HOPO4- further diminished the flexibility of t-HOPO4- and confined it in a limited conformational space. The strong interaction between the U4+ ion and t-HOPO4- was also implicated in the shortened residence time of water molecules.
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Elementos da Série Actinoide , Urânio , Quelantes/química , Ligantes , Piridonas/químicaRESUMO
BACKGROUND: To evaluate the efficacy and safety of transjugular intrahepatic portosystemic shunt (TIPS) on hepatic sinusoidal obstruction syndrome (HSOS) associated with consumption of Gynura segetum (GS). METHODS: We retrospectively reviewed 9 consecutive patients with GS-related HSOS who were refractory to supportive treatment and underwent TIPS at our institution between January 2014 and September 2019. The patients were evaluated for safety and efficacy, including TIPS complications and changes in portosystemic pressure gradient (PPG), ascites, total bilirubin, liver size and portal vein diameter. RESULTS: TIPS procedures were performed successfully in the 9 patients, and no technically-related complications due to the TIPS procedure were recorded. The PPG was improved by TIPS in all patients (mean PPG before TIPS, 30.4 ± 5.2 vs. 13.0 ± 4.1 mm Hg post-TIPS, P = 0.008). One patient who was lost to follow-up, whereas the remaining 8 patients survived with a median follow-up period of 12 months (range 5-39 months). Although the total bilirubin was significantly increased 5-7 days after TIPS compared with that before the procedure (3.57 ± 1.58 vs. 4.82 ± 2.06 mg/dl, P = 0.017), it returned to baseline levels at 1-month follow-up (3.53 ± 2.72 vs. 4.82 ± 2.06 mg/dl, P = 0.401). The patients experienced complete resolution or noticeable reduction of ascites (P < 0.001), significant reduction of liver size (16.7 ± 2.2 vs. 13.7 ± 1.7 cm, P = 0.018), and significant enlargement of the portal trunk (10.7 ± 2.5 vs. 13.4 ± 2.4 mm, P = 0.017) after TIPS compared to the pre-TIPS state. CONCLUSION: TIPS may offer a potentially useful treatment for the GS-related HSOS.
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Hepatopatia Veno-Oclusiva , Derivação Portossistêmica Transjugular Intra-Hepática , Medicamentos de Ervas Chinesas , Hepatopatia Veno-Oclusiva/etiologia , Humanos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Allergic asthma is the most common type of asthma which characterized by inflammatory responses of the airways. Alpinetin, a flavonoid compound derived from the ginger family of medicinal herbs, possesses various biological properties including anti-inflammatory, anti-oxidant and other medical effects. In this study, we aimed to evaluate the effects of alpinetin on OVA-induced allergic asthma, and further to examine its molecular mechanisms underlying these processes in vivo and in vitro. Mice were sensitized and challenged with OVA to build allergic asthma model in vivo. Bronchoalveolar lavage fluid (BALF) was collected for inflammatory cells analysis and lung tissues were examined for histopathological examination. The levels of IL-5, IL-13, IL-4, IgE, TNF-α, IL-6 and IL-1ß were determined by the respective ELISA kits. The PI3K/AKT/NF-κB and HO-1 signaling pathways were examined by western blot analysis. The results showed that alpinetin significantly ameliorated OVA-induced pathologic changes of lungs, such as decreasing massive inflammatory cell infiltration and mucus hypersecretion, and reduced the number of inflammatory cells in BALF. Alpinetin also decreased the OVA-induced levels of IL-4, IL-5, IL-13 and IgE. Furthermore, alpinetin inhibited OVA-induced phosphorylation of p65, IκB, PI3K and AKT, and the activity of HO-1 in vivo. More importantly, these anti-inflammatory effects and molecular mechanisms of alpinetin has also been confirmed in LPS-stimulated RAW 264.7 macrophages in vitro. In conclusion, above results indicate that alpinetin exhibites a potent anti-inflammatory activity in allergic asthma through modulating PI3K/AKT/NF-κB and HO-1 signaling pathways, which would be used as a promising therapy agent for allergic asthma.
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Asma/induzido quimicamente , Flavanonas/farmacologia , NF-kappa B/metabolismo , Ovalbumina/toxicidade , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Redução da Medicação , Flavanonas/administração & dosagem , Flavanonas/química , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Imunoglobulina E/sangue , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-4/sangue , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Estrutura Molecular , NF-kappa B/genética , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Células RAW 264.7 , Transdução de SinaisRESUMO
During manufacturing processes and in the storage period of tea, amino acids may undergo enantiomeric isomerization, converting their l- to d-forms. To examine the hypothesis, a method was developed for the analysis of the enantiomers in tea leaves. After enriched by ion-exchange solid-phase extraction, the enantiomeric pairs were separated by a chiral high performance liquid chromatography (HPLC) and subsequently detected and identified by using a high resolution quadrupole time-of-flight mass spectrometry (QTOF MS). Only l-forms of amino acids were found in fresh tea leaves. A total of 11 d-amino acids were found in 19 tea samples, ranging from trace amount to 43 µg/g. The results indicated that the enantioisomerization of amino acids occurred in post-harvest tea leaves, and affected by process conditions and storage time.
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Aminoácidos/análise , Aminoácidos/química , Camellia sinensis/química , Análise de Alimentos/métodos , Folhas de Planta/química , Chá/química , Cromatografia Líquida de Alta Pressão/métodos , Armazenamento de Alimentos , Espectrometria de Massas , Sensibilidade e Especificidade , Extração em Fase Sólida , EstereoisomerismoRESUMO
Wastewater treatment and generated biological sludge provide an alternative source of enzymes to conventional industrial production methods. Here, we present a protocol for extracting enzymes from activated sludge using ultrasonication and surfactant treatment. Under optimum conditions, ultrasound disruption of activated sludge gave recovery rates of protease and cellulase enzymes equivalent to 63.1% and â¼100%, respectively. The extracting of enzymes from activated sludge represents a potentially significant, high-value, resource recovery option for biological sludge generated by municipal wastewater treatment.
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Esgotos , Eliminação de Resíduos Líquidos , Resíduos Industriais , Extratos Vegetais , Águas ResiduáriasRESUMO
OBJECTIVE: In visceral obesity, an overactive endocannabinoid/CB1 receptor (CB1R) system promotes increased caloric intake and decreases energy expenditure, which are mitigated by global or peripheral CB1R blockade. In mice with diet-induced obesity (DIO), inhibition of food intake by the peripherally restricted CB1R antagonist JD5037 could be attributed to endogenous leptin due to the rapid reversal of hyperleptinemia that maintains leptin resistance, but the signaling pathway engaged by leptin has remained to be determined. METHODS: We analyzed the hypothalamic circuitry targeted by leptin following chronic treatment of DIO mice with JD5037. RESULTS: Leptin treatment or an increase in endogenous leptin following fasting/refeeding induced STAT3 phosphorylation in neurons in the arcuate nucleus (ARC) in lean and JD5037-treated DIO mice, but not in vehicle-treated DIO animals. Co-localization of pSTAT3 in leptin-treated mice was significantly less common with NPY+ than with POMC+ ARC neurons. The hypophagic effect of JD5037 was absent in melanocortin-4 receptor (MC4R) deficient obese mice or DIO mice treated with a MC4R antagonist, but was maintained in NPY-/- mice kept on a high-fat diet. CONCLUSIONS: Peripheral CB1R blockade in DIO restores sensitivity to endogenous leptin, which elicits hypophagia via the re-activation of melanocortin signaling in the ARC.
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Leptina/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Receptores para Leptina/efeitos dos fármacos , Animais , Núcleo Arqueado do Hipotálamo/metabolismo , Peso Corporal/fisiologia , Canabinoides/metabolismo , Dieta Hiperlipídica , Gorduras na Dieta/metabolismo , Ingestão de Alimentos/fisiologia , Hipotálamo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Neuropeptídeo Y/metabolismo , Obesidade/metabolismo , Pró-Opiomelanocortina/metabolismo , Pirazóis/farmacologia , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB1 de Canabinoide/fisiologia , Receptor Tipo 4 de Melanocortina/metabolismo , Receptores de Canabinoides/metabolismo , Receptores para Leptina/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologiaRESUMO
Major limitations of chalcones as clinical anticancer agents are water insolubility and poor bioavailability, which may be improved by a classic phosphate prodrug strategy that targets non-specific alkaline phosphatase (ALP) for releasing the parent drug in vivo. In this study, we found that BOC26P, a phosphate prodrug of chalcone OC26, exhibits excellent water solubility and improved plasma concentration in vivo by either i.v. or p.o. compared with the parent drug. In pace with decreased inhibitory activity of BOC26P against microtubule polymerization in vitro and in cells, the antiproliferative activity of BOC26P is attenuated in A549 and HLF cells. However, the antitumor effect of BOC26P increases in an A549 xenograft model as compared to the equimolar concentration of OC26, suggesting that complex tumor microenvironment would be another important influence factor to regulate the antitumor activity of BOC26Pin vivo. In conclusion, these observations showed that the traditional phosphate prodrug strategy would be a promising and easy method to increase water solubility and anticancer activity of chalcones for the clinical developments of anticancer agents.
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Antineoplásicos/síntese química , Chalconas/síntese química , Fosfatos/síntese química , Pró-Fármacos/síntese química , Células A549 , Animais , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Chalconas/farmacologia , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosfatos/farmacologia , Pró-Fármacos/farmacologia , Ratos , Ratos Sprague-Dawley , Solubilidade , Água/química , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
BACKGROUND: Glioma recurrence frequently occurs close to the marginal area of the surgical cavity as a result of residual infiltrating glioma cells. Fluorescence-guided surgery with 5-aminolevulinic acid (ALA) for resection of gliomas has been used as an effective therapeutic approach to discriminate malignant tissue from brain tissue and to facilitate patient prognosis. ALA-based photodynamic therapy is an effective adjuvant treatment modality for gliomas. However, insufficient protoporphyrin IX (PpIX) accumulation may limit the applicability of fluorescence-guided resection and photodynamic therapy in the marginal areas of gliomas. METHODS: To be able to understand how to overcome these issues, human glioma cells and normal astrocytes were used as the model system. Glioma cells and astrocytes were preconditioned with calcitriol for 48 hours and then incubated with ALA. Changes in ALA-induced PpIX fluorescence and cell survival after light exposure were assessed. Furthermore, expression of porphyrin synthetic enzymes in pretreated glioma cells was analyzed. RESULTS: Calcitriol can be administered prior to ALA as a non-toxic preconditioning regimen to significantly enhance ALA-induced PpIX levels and fluorescence. This increase in PpIX level was detected preferentially in glioma versus normal cells. Also, calcitriol pretreated glioma cells exhibited increased cell death following ALA-based photodynamic therapy. Furthermore, mechanistic studies documented that expression of the porphyrin synthesis enzymes coproporphyrinogen oxidase was increased by calcitriol at the mRNA level. CONCLUSION: We demonstrated for the first time a simple, non-toxic and highly effective preconditioning regimen to selectively enhance PpIX fluorescence and the response of ALA-PDT in glioma cells. This finding suggests that the combined treatment of glioma cells with calcitriol plus ALA may provide an effective and selective therapeutic modality to enhance ALA-induced PpIX fluorescent quality for improving discrimination of tumor tissue and PDT efficacy.
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Ácido Aminolevulínico/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Calcitriol/farmacologia , Fluorescência , Glioma/tratamento farmacológico , Imagem Molecular/métodos , Fotoquimioterapia/métodos , Astrócitos/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Enzimas/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/patologia , Humanos , Protoporfirinas/metabolismoRESUMO
RATIONALE: A number of epidemiological studies have suggested an association of hyperhomocysteinemia (HHcy) and abdominal aortic aneurysm (AAA), but discrepancies exist. In addition, we lack direct evidence supporting a causal role. OBJECTIVE: We determined the association and contribution of HHcy to AAA formation. METHODS AND RESULTS: We first performed a meta-analysis of studies involving 1489 subjects and found a strong association of HHcy and AAA (odds ratio, 7.39). Next, we used angiotensin II-infused male apolipoprotein E-deficient mice and tested whether HHcy contributes to AAA pathogenesis. Homocysteine (Hcy) supplement (1.8 g/L) in drinking water resulted in mild HHcy. Intriguingly, HHcy greatly increased the incidence of angiotensin II-induced AAA and aortic dissection in apolipoprotein E-deficient mice (vehicle versus Hcy: 50% versus 100%; P<0.05). Histology indicated HHcy markedly exaggerated aortic adventitial inflammation. Increased levels of proinflammatory interleukin-6 and monocyte chemoattractant protein-1 were preferentially colocalized within adventitial fibroblasts in HHcy plus angiotensin II mice, which suggested the importance of adventitial fibroblasts activation in Hcy-aggravated AAA. Hcy sequentially stimulated adventitial fibroblasts transformation into myofibroblasts, secretion of interleukin-6 and monocyte chemoattractant protein-1, and consequent recruitment of monocytes/macrophages to adventitial fibroblasts, which was abolished by the NADPH oxidase inhibitor diphenyliodonium. NADPH oxidase 4, but not other homologs of NADPH oxidase, was significantly upregulated by Hcy in adventitial fibroblasts, whereas NADPH oxidase 4 small interfering RNA silencing diminished Hcy-induced adventitial fibroblasts activation. Finally, folic acid supplement (0.071 µg/g per day) markedly reduced HHcy-aggravated angiotensin II-induced AAA formation in apolipoprotein E-deficient mice. CONCLUSIONS: HHcy may aggravate AAA formation at least partially via activating adventitial fibroblast NADPH oxidase 4.