RESUMO
Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus are symbiotic starters widely used in yogurt fermentation. They exchange metabolites to meet their nutritional demands during fermentation, promoting mutual growth. Although S. thermophilus produces fumaric acid, and the addition of fumaric acid has been shown to promote the growth of L. bulgaricus monoculture, whether fumaric acid produced by S. thermophilus is used by L. bulgaricus during coculture remains unclear. Furthermore, the importance of fumaric acid metabolism in the growth of L. bulgaricus is yet to be elucidated. Therefore, in this study, we investigated the importance of fumaric acid metabolism in L. bulgaricus monocultures and coculture with S. thermophilus. We deleted the fumarate reductase gene (frd), which is responsible for the metabolism of fumaric acid to succinic acid, in L. bulgaricus strains 2038 and NCIMB 701373. Both Δfrd strains exhibited longer fermentation times than their parent strains, and fumaric acid was metabolized to malic acid rather than succinic acid. Coculture of Δfrd strains with S. thermophilus 1131 also resulted in a longer fermentation time, and the accumulation of malic acid was observed. These results indicated that fumaric acid produced by S. thermophilus is used by L. bulgaricus as a symbiotic substance during yogurt fermentation and that the metabolism of fumaric acid to succinic acid by fumarate reductase is a key factor determining the fermentation ability of L. bulgaricus.
Assuntos
Fermentação , Fumaratos , Lactobacillus delbrueckii , Iogurte , Lactobacillus delbrueckii/metabolismo , Fumaratos/metabolismo , Iogurte/microbiologia , Succinato Desidrogenase/metabolismo , Streptococcus thermophilus/metabolismoRESUMO
Pre-zygotic interspecies incompatibility in angiosperms is an important mechanism to prevent unfavourable hybrids between species. Here we report our identification of STIGMATIC PRIVACY 2 (SPRI2), a transcription factor that has a zinc-finger domain and regulates interspecies barriers in Arabidopsis thaliana, via genome-wide association study. Knockout analysis of SPRI2/SRS7 and its paralogue SPRI2-like/SRS5 demonstrated their necessity in rejecting male pollen from other species within female pistils. Additionally, they govern mRNA transcription of xylan O-acetyltransferases (TBL45 and TBL40) related to cell wall modification, alongside SPRI1, a pivotal transmembrane protein for interspecific pollen rejection. SPRI2/SRS7 is localized as condensed structures in the nucleus formed via liquid-liquid phase separation (LLPS), and a prion-like sequence in its amino-terminal region was found to be responsible for the formation of the condensates. The LLPS-regulated SPRI2/SRS7 discovered in this study may contribute to the establishment of interspecific reproductive barriers through the transcriptional regulation of cell wall modification genes and SPRI1.
Assuntos
Arabidopsis , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Estudo de Associação Genômica Ampla , Arabidopsis/genética , Arabidopsis/metabolismo , Pólen/genética , ReproduçãoRESUMO
Animals properly perform sexual behaviors by using multiple sensory cues. However, neural mechanisms integrating multiple sensory cues and regulating motivation for sexual behaviors remain unclear. Here, we focused on peptidergic neurons, terminal nerve gonadotropin-releasing hormone (TN-GnRH) neurons, which receive inputs from various sensory systems and co-express neuropeptide FF (NPFF) in addition to GnRH. Our behavioral analyses using knockout medaka of GnRH (gnrh3) and/or NPFF (npff) demonstrated that some sexual behavioral repertoires were delayed, not disrupted, in gnrh3 and npff single knockout males, while the double knockout appeared to alleviate the significant defects that were observed in single knockouts. We also found anatomical evidence to show that both neuropeptides modulate the sexual behavior-controlling brain areas. Furthermore, we demonstrated that NPFF activates neurons in the preoptic area via indirect pathway, which is considered to induce the increase in motivation for male sexual behaviors. Considering these results, we propose a novel mechanism by which co-existing peptides of the TN-GnRH neurons, NPFF, and GnRH3 coordinately modulate certain neuronal circuit for the control of behavioral motivation. Our results may go a long way toward understanding the functional significance of peptidergic neuromodulation in response to sensory information from the external environments.
Assuntos
Hormônio Liberador de Gonadotropina/fisiologia , Oligopeptídeos/fisiologia , Oryzias , Ácido Pirrolidonocarboxílico/análogos & derivados , Comportamento Sexual Animal/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Encéfalo/metabolismo , Química Encefálica , Feminino , Técnicas de Inativação de Genes , Hormônio Liberador de Gonadotropina/análise , Hormônio Liberador de Gonadotropina/genética , Masculino , Neurônios/química , Neurônios/fisiologia , Oligopeptídeos/análise , Oligopeptídeos/genética , Filogenia , Ácido Pirrolidonocarboxílico/análise , Alinhamento de SequênciaRESUMO
Yogurt is traditionally fermented by a symbiotic starter culture of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. These bacteria exchange metabolites with each other to meet their nutritional demands during protocooperation, resulting in a shorter fermentation time. In this study, we investigated whether fumaric acid functions as a symbiotic agent to promote the growth of Lb. bulgaricus by evaluating 8 strains of Lb. bulgaricus and 7 strains of Strep. thermophilus. All the tested Lb. bulgaricus strains metabolized the added fumaric acid into succinic acid during monoculture in milk, and 6 strains (75%) showed shorter fermentation time compared with the control. The addition of malic acid showed similar trends as that of fumaric acid, indicating that the reverse tricarboxylic acid cycle was functioning in Lb. bulgaricus. All 7 Strep. thermophilus strains tested produced fumaric acid during monoculture in milk. Further, in Lb. bulgaricus 2038, the gene expression of fumarate reductase that converts fumaric acid to succinic acid, was higher in the coculture with Strep. thermophilus 1131 than in the monoculture. These findings indicate that fumaric acid produced by Strep. thermophilus can function as a symbiotic substance during yogurt fermentation to stimulate the growth of Lb. bulgaricus.
Assuntos
Lactobacillus delbrueckii , Animais , Fermentação , Fumaratos , Streptococcus thermophilus , IogurteRESUMO
Yogurt is a well-known nutritious and probiotic food and is traditionally fermented from milk using the symbiotic starter culture of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. However, yogurt consumption may cause health problems in lactose-intolerant individuals, and the demand for lactose-free yogurt has been increasing. The standard method to prepare lactose-free yogurt is to hydrolyze milk by lactase; however, this process has been reported to influence the fermentation properties of starter strains. This study aimed to investigate the fermentation properties of an industrial starter culture of L. bulgaricus 2038 and S. thermophilus 1131 in lactose-hydrolyzed milk and to examine the metabolic changes induced by glucose utilization. We found that the cell number of L. bulgaricus 2038, exopolysaccharide concentration, and viscosity in the coculture of L. bulgaricus 2038 and S. thermophilus 1131 was significantly increased in lactose-hydrolyzed milk compared with that in unhydrolyzed milk. Although the cell number of S. thermophilus 1131 showed no difference, production of formic acid and reduction of dissolved oxygen were enhanced in lactose-hydrolyzed milk. Further, in lactose-hydrolyzed milk, S. thermophilus 1131 was found to have increased the expression of NADH oxidase, which is responsible for oxygen reduction. These results indicated that glucose utilization promoted S. thermophilus 1131 to rapidly reduce the dissolved oxygen amount and produce a high concentration of formic acid, presumably resulting in the increased cell number of L. bulgaricus 2038 in the coculture. Our study provides basic information on the metabolic changes in starter strains in lactose-hydrolyzed milk, and demonstrates that lactose-free yogurt with increased cell number of L. bulgaricus can be prepared without delay in fermentation and decrease in the cell number of S. thermophilus.
Assuntos
Fermentação , Lactobacillus delbrueckii/metabolismo , Lactose/metabolismo , Streptococcus thermophilus/metabolismo , Animais , Reatores Biológicos , Hidrólise , Lactase/metabolismo , Lactose/análise , Leite/química , Probióticos , Iogurte/análise , Iogurte/microbiologiaRESUMO
Streptococcus thermophilus is widely used for producing fermented dairy products such as yogurt and cheese. Some S. thermophilus strains possessing the cell-wall protease PrtS show high proteolytic activity and fast acidification properties, which are very useful in industrial starters. However, few S. thermophilus strains possessing the prtS gene have been isolated from the environment. To clarify whether or not S. thermophilus strains possessing the prtS gene are present in Japan, we isolated S. thermophilus from raw milk collected in Japan from 2011 to 2017 and investigated the strains for the presence of prtS by PCR. A total of 172 S. thermophilus strains were isolated, and 59 strains were confirmed to possess prtS. We measured fermentation times of 59 prtS-positive strains in skim milk broth and found that 53 strains showed fast acidification properties, finishing fermentation within 10 hr. However, the remaining 6 prtS-positive strains showed slow acidification properties, and they had several amino acid mutations in PrtS compared with fast acidifying S. thermophilus LMD-9 and 4F44. These results demonstrate that S. thermophilus strains possessing prtS are prevalent in Japan and that some prtS-positive strains could lose their fast acidifying properties through mutations in PrtS.
RESUMO
Probiotic-rich foods are consumed without much restriction. We report here, a case of septic shock caused by yogurt derived Lactobacillus species in a 54-year-old male patient with acute promyelocytic leukemia, in second complete remission, and who was an autologous stem cell transplantation recipient. He received high dose chemotherapy and autologous peripheral blood stem cell transplantation. He ingested commercially available probiotic-enriched yogurt because of severe diarrhea. One week later, he developed septic shock, and the pathogen was determined by strain-specific PCR analysis as Lactobacillus rhamnosus GG (ATCC 53103), which was found to be identical with the strain in the yogurt he consumed. Thus, because even low virulent Lactobacilli in the probiotic products can be pathogenic in the compromised hosts, ingestion of such products should be considered with caution in neutropenic patients with severe diarrhea, such as stem cell transplantation recipients.
Assuntos
Lacticaseibacillus rhamnosus/fisiologia , Leucemia/terapia , Probióticos/efeitos adversos , Sepse/etiologia , Iogurte/efeitos adversos , Transplante de Células-Tronco Hematopoéticas , Humanos , Lacticaseibacillus rhamnosus/crescimento & desenvolvimento , Masculino , Pessoa de Meia-Idade , Probióticos/análise , Sepse/microbiologia , Transplante Autólogo , Iogurte/microbiologiaRESUMO
There are some cases that are difficult to cure with only circumferential pulmonary vein isolation (CPVI) of persistent atrial fibrillation (PerAF). Recently, prolonged interatrial conduction times (IACTs), which seem to be associated with progressive remodeled atria, have been reported as a predictor of new-onset AF. This study aimed to investigate the prognostic value of a prolonged IACT for predicting AF recurrences after CPVI of PerAF. One hundred thirteen patients who underwent CPVI without an empirical substrate modification of PerAF were retrospectively analyzed. The IACT was defined as the interval from the earliest P-wave onset on the ECG to the latest activation in the coronary sinus and was measured after achieving the CPVI and conversion to sinus rhythm. During a mean 22.7-month follow-up after the initial procedure, 56 patients (50%) had AF recurrences. Patients with AF recurrence had a longer IACT than those without AF recurrence (p < 0.001). The best discriminative cut-off value for the IACT was 123 ms (sensitivity 53%, specificity 85%). In a Cox multivariate analysis, a prolonged IACT of ≥ 123 ms was the only independent predictor (hazard ratio: 2.38; 95% confidence interval: 1.36-4.16, p = 0.002) of being associated with the incidence of an AF recurrence. Even after multiple CPVI procedures, patients with an IACT ≥ 123 ms had a higher AF recurrence rate than those with an IACT < 123 ms (p = 0.002). In conclusion, a prolonged IACT of ≥ 123 ms may be a useful marker for predicting AF recurrences after both initial and multiple CPVI procedures for PerAF.
Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Sistema de Condução Cardíaco/cirurgia , Frequência Cardíaca/fisiologia , Veias Pulmonares/cirurgia , Fibrilação Atrial/fisiopatologia , Mapeamento Potencial de Superfície Corporal , Feminino , Seguimentos , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Tempo , Resultado do TratamentoRESUMO
The aim of this study was to assess the safety and optimal dose of deferasirox for the treatment of iron overload after allogeneic hematopoietic cell transplantation (HCT). The primary endpoint was the maximum tolerated dose of deferasirox that was determined by the intrapatient dose escalation methods. A total of 16 patients with post-HCT iron overload were enrolled in the study. After excluding one case of early relapse, 15 remained evaluable. Their median age was 42 years (range 22-68). Median time from HCT to deferasirox administration was 9 months (range 6-84). Deferasirox was started at a dose of 5 mg/kg, and the dose was increased to 7.5 and 10 mg/kg every 4 weeks unless there were no grade ≥ 2 of adverse events. Achievement rates of planned medication were 80% in 5 mg/kg (12 of 15), 73% in 7.5 mg/kg (11 of 15), and 60% in 10 mg/kg (9 of 15), respectively. The reasons for discontinuation of the drug were grade 2 of adverse events (n = 4), late relapse (n = 1), and self-cessation (n = 1). None of the patients developed grade ≥ 3 of adverse events or exacerbation of GVHD. Among 11 evaluable cases, mean value of ferritin decreased from 1560 ng/ml pre-treatment to 1285 ng/ml post-treatment. These data suggested that 10 mg/kg of deferasirox may be maximum tolerated dose when given after HCT. Our dose escalating method of deferasirox is useful to identify the optimal dosage of the drug in each patient. TRIAL REGISTRATION: UMIN000011251.
Assuntos
Benzoatos/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Quelantes de Ferro/administração & dosagem , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Triazóis/administração & dosagem , Adulto , Idoso , Aloenxertos , Deferasirox , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
Cancer stem-like cells (CSCs)/ cancer-initiating cells (CICs) are defined by their higher tumor-initiating ability, self-renewal capacity and differentiation capacity. CSCs/CICs are resistant to several therapies including chemotherapy and radiotherapy. CSCs/CICs thus are thought to be responsible for recurrence and distant metastasis, and elucidation of the molecular mechanisms of CSCs/CICs are essential to design CSC/CIC-targeting therapy. In this study, we analyzed the molecular aspects of gynecological CSCs/CICs. Gynecological CSCs/CICs were isolated as ALDH1high cell by Aldefluor assay. The gene expression profile of CSCs/CICs revealed that several genes related to stress responses are preferentially expressed in gynecological CSCs/CICs. Among the stress response genes, a small heat shock protein HSP27 has a role in the maintenance of gynecological CSCs/CICs. The upstream transcription factor of HSP27, heat shock factior-1 (HSF1) was activated by phosphorylation at serine 326 residue (pSer326) in CSCs/CICs, and phosphorylation at serine 326 residue is essential for induction of HSP27. Immunohistochemical staining using clinical ovarian cancer samples revealed that higher expressions of HSF1 pSer326 was related to poorer prognosis. These findings indicate that activation of HSF1 at Ser326 residue and transcription of HSP27 is related to the maintenance of gynecological CSCs/CICs.
Assuntos
Regulação Neoplásica da Expressão Gênica , Doenças dos Genitais Femininos/genética , Doenças dos Genitais Femininos/metabolismo , Proteínas de Choque Térmico HSP27/genética , Fatores de Transcrição de Choque Térmico/metabolismo , Células-Tronco Neoplásicas/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Doenças dos Genitais Femininos/patologia , Proteínas de Choque Térmico HSP27/química , Proteínas de Choque Térmico HSP27/metabolismo , Xenoenxertos , Humanos , Camundongos , Mutação , Fosforilação , Interferência de RNA , Serina/metabolismo , Células Tumorais CultivadasRESUMO
Cancer stem-like cells (CSCs)/cancer-initiating cells (CICs) are small sub-population of cancer cells that are endowed with higher tumor-initiating ability, self-renewal ability and differentiation ability. CSCs/CICs could be isolated as high aldehyde dehydrogenase 1 activity cells (ALDH1high) from various cancer samples. In this study, we isolated urothelial carcinoma CSCs/CICs as ALDHhigh cells and investigated the molecular aspects. ALDH1high cells showed greater sphere-forming ability and higher tumor-initiating ability in immune-deficient mice than those of ALDH1low cells, indicating that CSCs/CICs were enriched in ALDH1high cells. cDNA microarray analysis revealed that an ionotropic glutamate receptor glutamate receptor, ionotropic, kainate 2 (GRIK2) was expressed in ALDH1high cells at a higher level than that in ALDH1low cells. GRIK2 gene knockdown by siRNAs decreased the sphere-forming ability and invasion ability, whereas GRIK2 overexpression increased the sphere-forming ability, invasion ability and tumorigenicity, indicating that GRIK2 has a role in the maintenance of CSCs/CICs. Immunohistochemical staining revealed that higher levels of GRIK2 and ALDH1 expression were related to poorer prognosis in urinary tract carcinoma cases. The findings indicate that GRIK2 has a role in the maintenance of urothelial CSCs/CICs and that GRIK2 and ALDH1 can be prognosis prediction markers for urinary tract carcinomas.
Assuntos
Isoenzimas/metabolismo , Células-Tronco Neoplásicas/patologia , Receptores de Ácido Caínico/metabolismo , Retinal Desidrogenase/metabolismo , Neoplasias Urológicas/genética , Urotélio/patologia , Família Aldeído Desidrogenase 1 , Animais , Carcinogênese , Linhagem Celular Tumoral , Autorrenovação Celular/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos SCID , Células-Tronco Neoplásicas/metabolismo , Prognóstico , RNA Interferente Pequeno/genética , Receptores de Ácido Caínico/genética , Neoplasias Urológicas/diagnóstico , Neoplasias Urológicas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Receptor de GluK2 CainatoRESUMO
Colorectal cancer (CRC) is one of the most common malignancy, and the prognosis is not still satisfactory due to treatment resistance, recurrence and distant metastasis. Cancer stem cells (CSCs)/cancer-initiating cells (CICs) is endowed with higher tumor-initiating ability, self-renewal ability and differentiation ability, and CSCs/CICs are resistant to treatments. Thus, CSCs/CICs are thought to be responsible for recurrence and distant metastasis, and eradication of CSCs/CICs is essential to cure CRCs. However, the molecular mechanisms of CSCs/CICs are remain unknown, and we aimed to elucidate molecular aspects of CR-CSCs/CICs in this study. We screened the transcriptome data of primary human CR-CSCs/CICs that we previously established, and found that LEM domain containing 1 (LEMD1) is preferentially expressed in CR-CSCs/CICs. LEMD1 belongs to cancer-testis (CT) antigen, and has five transcript variants (variant 1 [V1] - variant 5 [V5]). We found that LEMD1 V1, V2 and V3 is expressed in testis and CR-CSCs/CICs, whereas LEMD1 V4 and V5 is ubiquitously expressed. LEMD1 gene knockdown experiments using siRNAs and gene overexpression experiments revealed that LEMD1 has a role in the maintenance of CR-CSCs/CICs. These observations indicate that CR-CSC/CIC-specific LEMD1 variants are reasonable target of CR-CSC/CIC-targeted therapy.
Assuntos
Neoplasias Colorretais/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Sobrevivência Celular/genética , Neoplasias Colorretais/patologia , Feminino , Células HCT116 , Células HT29 , Humanos , Masculino , Células-Tronco Neoplásicas/patologia , Isoformas de Proteínas/genética , Interferência de RNA , Splicing de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esferoides Celulares/metabolismo , Testículo/metabolismoRESUMO
Colorectal carcinoma (CRC) is one of the most frequently diagnosed cancers and the leading cause of cancer-related death for both men and women. Recent studies have revealed that a small sub-population of cancer cells, termed cancer stem-like cells (CSCs)/cancer-initiating cells (CICs), are endowed with tumor-initiating ability, self-renewal ability and differentiation ability. CSCs/CICs are resistant to current therapies including chemotherapy and radiotherapy. Thus, CSCs/CICs are responsible for recurrence and metastasis, and eradication of CSCs/CICs is essential to cure cancer. In this study, we isolated CR-CSCs/CICs as sphere-cultured cells and found that a product derived from LY6/PLAUR domain containing 3 (LYPD3) is preferentially expressed in CSCs/CICs. Gene overexpression and gene knockdown experiments revealed that LYPD3 has a role in the maintenance of CR-CSCs/CICs. The findings provide a novel molecular insight into CR-CSCs/CICs.
Assuntos
Moléculas de Adesão Celular/genética , Regulação Neoplásica da Expressão Gênica , Células-Tronco Neoplásicas/metabolismo , Esferoides Celulares/metabolismo , Aldeído Desidrogenase/genética , Aldeído Desidrogenase/metabolismo , Família Aldeído Desidrogenase 1 , Moléculas de Adesão Celular/antagonistas & inibidores , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Células HCT116 , Células HT29 , Humanos , Proteína Homeobox Nanog/genética , Proteína Homeobox Nanog/metabolismo , Células-Tronco Neoplásicas/patologia , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Retinal Desidrogenase , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Transdução de Sinais , Esferoides Celulares/patologiaRESUMO
Cylindradines A and B are members of the oroidin-derived pyrrole-imidazole alkaloid (PIA) family. They possess a characteristic pyrrole-3-carbamoyl moiety, which is unusual among PIAs. We achieved a total synthesis of (+)-cylindradine B by applying a Pictet-Spengler-type reaction followed by oxidative cyclization in the presence of hypervalent iodine to construct the pyrrole-3-carbamoyl and cyclic guanidine with N,N'-aminal moieties at C6 and C10.
RESUMO
Human cancer stem-like cells (CSCs)/cancer-initiating cells (CICs) can be isolated as side population (SP) cells, aldehyde dehydrogenase high (ALDHhigh) cells or cell surface marker-positive cells including CD44+ cells and CD133+ cells. CSCs/CICs and non-CSCs/CICs are unstable in in vitro culture, and CSCs/CICs can differentiate into non-CSCs/CICs and some non-CSCs/CICs can dedifferentiate into CSCs/CICs. Therefore, experiments using a large amount of CSCs/CICs are technically very difficult. In this study, we isolated single cell clones from SP cells and main population (MP) cells derived from the human colon cancer cell line SW480. SP analysis revealed that SP clone cells had relatively high percentages of SP cells, whereas MP clone cells showed very few SP cells, and the phenotypes were sustainable for more than 2 months of in vitro culture. Xenograft transplantation revealed that SP clone cells have higher tumor-initiating ability than that of MP clone cells and SP clone cell showed higher chemo-resistance compared with MP clone cells. These results indicate that SP clone cells derived from SW480 cells are enriched with CSCs/CICs, whereas MP clone cells are pure non-CSCs/CICs. SP clone cells and MP clone cells are a very stable in vitro CSC/CIC-enriched and non-CSC/CIC model for further analysis.
Assuntos
Neoplasias do Colo/patologia , Células-Tronco Neoplásicas/fisiologia , Células da Side Population/fisiologia , Animais , Ciclo Celular , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Transplante de Neoplasias , Células-Tronco Neoplásicas/transplante , Células da Side Population/transplanteRESUMO
Cancer stem-like cells (CSCs)/cancer-initiating cells (CICs) are reasonable targets for cancer therapy. However, recent studies have revealed that some non-CSCs/CICs have plastic ability and can dedifferentiate into CSCs/CICs. Therefore, an understanding of the molecular mechanisms that control the plasticity is essential to achieve CSC/CIC-targeting therapy. In this study, we analyzed the plasticity of lung cancer cells and found that lung non-CSCs/CICs can dedifferentiate into CSCs/CICs in accordance with the expression of stem cell transcription factor SOX2. SOX2 expression was induced by the transcription factor HOXA5. Oxidative stress repressed the expression of HDAC8 and then induced histone 3 acetylation and increased the expression of HOXA5 and SOX2. These findings indicate that lung cancer cells have plasticity under a condition of oxidative stress and that HOAX5 has a critical role in dedifferentiation.
Assuntos
Desdiferenciação Celular , Proteínas de Homeodomínio/metabolismo , Neoplasias Pulmonares/metabolismo , Células-Tronco Neoplásicas/metabolismo , Estresse Oxidativo , Fatores de Transcrição SOXB1/metabolismo , Células da Side Population/metabolismo , Acetilação , Animais , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Histona Desacetilases/metabolismo , Histonas/química , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Transplante de Neoplasias , RNA Interferente Pequeno/metabolismo , Proteínas Repressoras/metabolismo , TransfecçãoRESUMO
The distribution characteristics of aerosolized PEGylated liposomes in alveolar epithelial lining fluid (ELF) were examined in rats, and the ensuing mechanisms were investigated in the in vitro uptake and protein adsorption experiments. Nonmodified or PEGylated liposomes (particle size 100 nm) were aerosolized into rat lungs. PEGylated liposomes were distributed more sustainably in ELFs than nonmodified liposomes. Furthermore, the uptake of PEGylated liposomes by alveolar macrophages (AMs) was less than that of nonmodified liposomes. In further in vitro uptake experiments, nonmodified and PEGylated liposomes were opsonized with rat ELF components and then added to NR8383 cells as cultured rat AMs. The uptake of opsonized PEGylated liposomes by NR8383 cells was lower than that of opsonized nonmodified liposomes. Moreover, the protein absorption levels in opsonized PEGylated liposomes were lower than those in opsonized nonmodified liposomes. These findings suggest that sustained distributions of aerosolized PEGylated liposomes in ELFs reflect evasion of liposomal opsonization with surfactant proteins and consequent reductions in uptake by AMs. These data indicate the potential of PEGylated liposomes as aerosol-based drug delivery system that target ELF for the treatment of respiratory diseases.
Assuntos
Aerossóis/farmacocinética , Lipossomos/farmacocinética , Pulmão/metabolismo , Macrófagos Alveolares/metabolismo , Aerossóis/química , Animais , Líquidos Corporais/metabolismo , Células Cultivadas , Lipossomos/química , Masculino , Tamanho da Partícula , Polietilenoglicóis/química , Ratos , Propriedades de SuperfícieRESUMO
Polyglutamine (polyQ) diseases comprise neurodegenerative disorders caused by expression of expanded polyQ-containing proteins. The cytotoxicity of the expanded polyQ-containing proteins is closely associated with aggregate formation. In this study, we report that a novel J-protein, DNAJ (HSP40) Homolog, Subfamily C, Member 8 (DNAJC8), suppresses the aggregation of polyQ-containing protein in a cellular model of spinocerebellar ataxia type 3 (SCA3), which is also known as Machado-Joseph disease. Overexpression of DNAJC8 in SH-SY5Y neuroblastoma cells significantly reduced the polyQ aggregation and apoptosis, and DNAJC8 was co-localized with the polyQ aggregation in the cell nucleus. Deletion mutants of DNAJC8 revealed that the C-terminal domain of DNAJC8 was essential for the suppression of polyQ aggregation, whereas the J-domain was dispensable. Furthermore, 22-mer oligopeptide derived from C-termilal domain could suppress the polyQ aggregation. These results indicate that DNAJC8 can suppress the polyQ aggregation via a distinct mechanism independent of HSP70-based chaperone machinery and have a unique protective role against the aggregation of expanded polyQ-containing proteins such as pathogenic ataxin-3 proteins.
Assuntos
Ataxina-3/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Doença de Machado-Joseph/metabolismo , Neurônios/metabolismo , Proteínas Repressoras/metabolismo , Sítios de Ligação , Linhagem Celular , Células HeLa , Humanos , Ligação Proteica , Domínios Proteicos , Multimerização ProteicaRESUMO
Asymmetric synthesis of tetrahydrobenzodiazepines was achieved by transfer hydrogenation of dihydrobenzodiazepines with benzothiazoline having a hydrogen-bonding donor substituent by means of a newly synthesized chiral phosphoric acid. This method was applicable to various racemic dihydrobenzodiazepines to give the corresponding products in good yields with excellent diastereoselectivities and enantioselectivities taking advantage of the dynamic kinetic resolution. Furthermore, the effect of bulky substituent at 3,3'-position on the catalyst and hydrogen-bonding donor substituent on benzothiazoline was fully elucidated by the theoretical study.
RESUMO
The impact of pre-transplant serum C-reactive protein (CRP) level on the outcome of reduced-intensity conditioning allogeneic hematopoietic stem cell transplantation (RIC allo-SCT) is unclear. This study retrospectively investigated 78 patients who underwent RIC allo-SCT between 2005 and 2013. The conditioning regimen consisted of fludarabine and melphalan with/without total body irradiation. The 3-year overall survival of high CRP (43.6 % of all patients) patients was significantly worse than that of normal CRP patients in whom CRP was ≤0.3 mg/dl (26.7 vs. 74.1 %, P < 0.001). Both the CRP level before transplantation and disease risk status were independent prognostic factors for overall survival by multivariate analysis. CRP was not a significant predictor of NRM by multivariate analysis (hazard ratio 3.2, 95 % confidence interval 0.8-13.1, P = 0.100). These results suggest that measuring the CRP level before transplantation can be useful to predicting the outcome of RIC allo-SCT.