RESUMO
Nuclear expression of protein kinase CK2α is reportedly elevated in human carcinomas, but mechanisms underlying its variable localization in cells are poorly understood. This study demonstrates a functional connection between nuclear CK2 and gene expression in relation to cell proliferation. Growth stimulation of quiescent human normal fibroblasts and phospho-proteomic analysis identified a pool of CK2α that is highly phosphorylated at serine 7. Phosphorylated CK2α translocates into the nucleus, and this phosphorylation appears essential for nuclear localization and catalytic activity. Protein signatures associated with nuclear CK2 complexes reveal enrichment of apparently unique transcription factors and chromatin remodelers during progression through the G1 phase of the cell cycle. Chromatin immunoprecipitation-sequencing profiling demonstrated recruitment of CK2α to active gene loci, more abundantly in late G1 phase than in early G1, notably at transcriptional start sites of core histone genes, growth stimulus-associated genes, and ribosomal RNAs. Our findings reveal that nuclear CK2α complexes may be essential to facilitate progression of the cell cycle, by activating histone genes and triggering ribosomal biogenesis, specified in association with nuclear and nucleolar transcriptional regulators.
Assuntos
Redes Reguladoras de Genes , Histonas , Humanos , Ciclo Celular/genética , Proliferação de Células/genética , ProteômicaRESUMO
OBJECTIVE: Postmenopausal women are at increased risk of metabolic diseases such as obesity and diabetes. Therefore, the chemoprevention of postmenopausal changes in health via dietary supplements is important. Syringic acid (SA) is a phenolic compound present in the fruit of the assai palm, Euterpe oleracea, and in the mycelium of the shiitake mushroom, Lentinula edodes. This compound shows no affinity for estrogen receptors and may exert disease-preventive effects. Reportedly, dietary SA ameliorates high-fat diet-induced obesity in mice; however, its effects on estrogen deficiency-induced obesity are still unclear. Therefore, in this study, we investigated whether and how dietary SA affects these factors in ovariectomized (OVX) mice. METHODS: Ten-week-old OVX mice were fed SA-containing diets (100âmg/kg body weight/d) for 12âweeks. Their body weights, food intake, and uterus weights as well as other parameters were measured and comparisons were made with mice in the control group. RESULTS: Dietary SA did not affect the body weight, food intake, or uterus weight of OVX mice over the study period; however, the SA-fed group showed lower fat mass (ie, visceral, subcutaneous, and total fat) than the OVX-control group (11.1â±â3.3 vs. 8.3â±â2.4, Pâ<â0.05; 7.9â±â1.1 vs. 5.9â±â1.6, Pâ<â0.05; 19.0â±â4.2 vs. 14.1â±â3.8, Pâ<â0.05, respectively). Furthermore, blood analysis revealed that SA-treatment resulted in a dose-dependent decrease and increase in serum triglyceride (59.2â±â8.3 vs. 43.9â±â12.2âmg/dL Pâ<â0.05) and adiponectin (7.7â±â0.3 vs. 9.5â±â0.6âµg/mL, Pâ<â0.05) levels, respectively. CONCLUSIONS: These results suggest that the SA diet improves lipid metabolism without affecting the uterus in OVX mice. Therefore, dietary SA has potential applicability for the prevention of postmenopausal obesity and type 2 diabetes.
Assuntos
Diabetes Mellitus Tipo 2 , Animais , Peso Corporal , Dieta Hiperlipídica/efeitos adversos , Feminino , Ácido Gálico/análogos & derivados , Humanos , Camundongos , Obesidade/prevenção & controle , OvariectomiaRESUMO
Differentiation-inducing factor-1 (DIF-1) is a chlorinated alkylphenone (a polyketide) found in the cellular slime mold Dictyostelium discoideum. DIF-1 and its derivative, DIF-1(3M) promote glucose consumption in vitro in mammalian cells and in vivo in diabetic rats; they are expected to be the leading antiobesity and antidiabetes compounds. In this study, we investigated the mechanisms underlying the actions of DIF-1 and DIF-1(3M). In isolated mouse liver mitochondria, these compounds at 2-20 µM promoted oxygen consumption in a dose-dependent manner, suggesting that they act as mitochondrial uncouplers, whereas CP-DIF-1 (another derivative of DIF-1) at 10-20 µM had no effect. In confluent mouse 3T3-L1 fibroblasts, DIF-1 and DIF-1(3M) but not CP-DIF-1 induced phosphorylation (and therefore activation) of AMP kinase (AMPK) and promoted glucose consumption and metabolism. The DIF-induced glucose consumption was reduced by compound C (an AMPK inhibitor) or AMPK knock down. These data suggest that DIF-1 and DIF-1(3M) promote glucose uptake, at least in part, via an AMPK-dependent pathway in 3T3-L1 cells, whereas cellular metabolome analysis revealed that DIF-1 and DIF-1(3M) may act differently at least in part.
Assuntos
Adenilato Quinase/metabolismo , Dictyostelium/metabolismo , Glucose/metabolismo , Hexanonas/farmacologia , Hidrocarbonetos Clorados/farmacologia , Metaboloma/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Pirazóis/farmacologia , Pirimidinas/farmacologia , Células 3T3 , Adenilato Quinase/antagonistas & inibidores , Animais , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Técnicas de Silenciamento de Genes , Camundongos , Mitocôndrias/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Fosforilação , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacosRESUMO
Interleukin-31 (IL-31) is involved in excessive development of cutaneous sensory nerves in atopic dermatitis (AD), leading to severe pruritus. We previously reported that PQA-18, a prenylated quinolinecarboxylic acid (PQA) derivative, is an immunosuppressant with inhibition of p21-activated kinase 2 (PAK2) and improves skin lesions in Nc/Nga mice as an AD model. In the present study, we investigate the effect of PQA-18 on sensory nerves in lesional skin. PQA-18 alleviates cutaneous nerve fiber density in the skin of Nc/Nga mice. PQA-18 also inhibits IL-31-induced sensory nerve fiber outgrowth in dorsal root ganglion cultures. Signaling analysis reveals that PQA-18 suppresses phosphorylation of PAK2, Janus kinase 2, and signal transducer and activator of transcription 3 (STAT3), activated by IL-31 receptor (IL-31R), resulting in inhibition of neurite outgrowth in Neuro2A cells. Gene silencing analysis for PAK2 confirms the requirement for STAT3 phosphorylation and neurite outgrowth elicited by IL-31R activation. LC/MS/MS analysis reveals that PQA-18 prevents the formation of PAK2 activation complexes induced by IL-31R activation. These results suggest that PQA-18 inhibits the IL-31 pathway through suppressing PAK2 activity, which suppresses sensory nerve outgrowth. PQA-18 may be a valuable lead for the development of a novel drug for pruritus of AD.
Assuntos
Ácidos Carboxílicos/farmacologia , Dermatite Atópica/tratamento farmacológico , Interleucinas/antagonistas & inibidores , Quinolinas/farmacologia , Células Receptoras Sensoriais/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Dermatite Atópica/metabolismo , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Interleucinas/metabolismo , Janus Quinase 2/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fibras Nervosas/efeitos dos fármacos , Fibras Nervosas/patologia , Fatores de Crescimento Neural/metabolismo , Sistema Nervoso Periférico/efeitos dos fármacos , Sistema Nervoso Periférico/metabolismo , Prenilação de Proteína , Fator de Transcrição STAT3/metabolismo , Células Receptoras Sensoriais/metabolismo , Transdução de Sinais/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/metabolismo , Quinases Ativadas por p21/metabolismoRESUMO
Overexpression of the ubiquitous protein kinase, CK2α, has been reported in various human cancers. Here, we demonstrate that nuclear and nucleolar CK2α localization in invasive ductal carcinomas of the breast is a reliable predictor of poor prognosis. Cellular localization of CK2α in nuclei and nucleoli was analyzed immunohistochemically using surgical tissue blocks from 112 patients, who had undergone surgery without neoadjuvant chemotherapy. Clinical data collection and median follow-up period were for more than 5 y. In total, 93.8% of patients demonstrated elevated CK2α expression in nuclei and 36.6% of them displayed elevated expression predominantly in nucleoli. Clinicopathological malignancy was strongly correlated with elevated nuclear and nucleolar CK2α expression. Recurrence-free survival was significantly worse (P = .0002) in patients with positive nucleolar CK2α staining. The 5-y survival rate decreased to a roughly 50% in nucleolar CK2α-positive patients of triple-negative (P = .0069) and p Stage 3 (P = .0073) groups. In contrast, no patients relapsed or died in the triple-negative group who exhibited a lack of nucleolar CK2α staining. Evaluation of nucleolar CK2α staining showed a high secondary index with a hazard ratio of 6.629 (P = .001), following lymph node metastasis with a hazard ratio of 14.30 (P = .0008). Multivariate analysis demonstrated that nucleolar CK2α is an independent factor for recurrence-free survival. Therefore, we propose that histochemical evaluation of nucleolar CK2α-positive staining may be a new and robust prognostic indicator for patients who need further treatment. Functional consequences of nucleolar CK2 dysfunction may be a starting point to facilitate development of novel treatments for invasive breast carcinoma.
Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Caseína Quinase II/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/enzimologia , Carcinoma Ductal de Mama/enzimologia , Nucléolo Celular/enzimologia , Núcleo Celular/enzimologia , Feminino , Humanos , Células MCF-7 , Pessoa de Meia-Idade , PrognósticoRESUMO
Inhibition of the complement activation has emerged as an option for treatment of a range of diseases. Activation of the lectin and alternative pathways (LP and AP, respectively) contribute to the deterioration of conditions in certain diseases such as ischemia-reperfusion injuries and age-related macular degeneration (AMD). In the current study, we generated dual complement inhibitors of the pathways MAp44-FH and sMAP-FH by fusing full-length MAp44 or small mannose-binding lectin-associated protein (sMAP), LP regulators, with the N-terminal five short consensus repeat (SCR) domains of complement factor H (SCR1/5-FH), an AP regulator. The murine forms of both fusion proteins formed a complex with endogenous mannose-binding lectin (MBL) or ficolin A in the circulation when administered in mice intraperitoneally. Multiple complement activation assays revealed that sMAP-FH had significantly higher inhibitory effects on activation of the LP and AP in vivo as well as in vitro compared to MAp44-FH. Human form of sMAP-FH also showed dual inhibitory effects on LP and AP activation in human sera. Our results indicate that the novel fusion protein sMAP-FH inhibits both the LP and AP activation in mice and in human sera, and could be an effective therapeutic agent for diseases in which both the LP and AP activation are significantly involved.
Assuntos
Inativadores do Complemento/metabolismo , Via Alternativa do Complemento/imunologia , Lectinas/imunologia , Lectina de Ligação a Manose/metabolismo , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo , Animais , Ativação do Complemento/imunologia , Fator H do Complemento/imunologia , Fator H do Complemento/metabolismo , Inativadores do Complemento/imunologia , Feminino , Humanos , Lectinas/metabolismo , Lectina de Ligação a Manose/imunologia , Serina Proteases Associadas a Proteína de Ligação a Manose/imunologia , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Astrocytes release exosomes that regulate neuronal cell function. 1-methyl-4-phenylpyridinium (MPP+) is a well-known neurotoxin used to induce cell death in in vitro Parkinson's disease models, and microRNA (miRNA) transferred by released exosomes can regulate its mechanisms. Here, we demonstrated that exosomes released from normal astrocytes (ADEXs), but not exosomes derived from MPP+-stimulated astrocytes (MPP+-ADEXs), significantly attenuate MPP+-induced cell death in SH-SY5Y cells and primary mesencephalic dopaminergic neuron cultures, and reduce expression of mitogen-activated protein kinase kinase 4 (MKK4), an important upstream kinase in the c-Jun N-terminal kinase cell death pathway. Similar neuroprotective results were obtained from primary hippocampal neuron cultures, an in vitro glutamate excitotoxicity model. Through small-RNA sequencing of exosomal miRNA, we identified miR-200a-3p as the most down-regulated miRNA expressed in MPP+-ADEXs. miRNA target analysis and reporter assay confirmed that miR-200a-3p targets MKK4 through binding to two independent sites on the 3'-UTR of Map2k4/MKK4 mRNA. Treatment with miR-200a-3p mimic suppressed both MKK4 mRNA and protein expressions, and attenuated cell death in MPP+-treated SH-SY5Y cells and glutamate-treated hippocampal neuron cultures. Our results suggest that normal astrocytes release miR-200a-3p which exhibits a neuroprotective effect through down-regulation of MKK4.
Assuntos
1-Metil-4-fenilpiridínio/toxicidade , Apoptose/fisiologia , Astrócitos/efeitos dos fármacos , Exossomos/metabolismo , MAP Quinase Quinase 4/metabolismo , MicroRNAs/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Astrócitos/metabolismo , Materiais Biomiméticos/farmacologia , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Linhagem Celular Tumoral , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Exossomos/efeitos dos fármacos , Células HEK293 , Humanos , MAP Quinase Quinase 4/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BLRESUMO
The complement system, a part of the innate immune system, can be activated via three different pathways. In the alternative pathway, a factor D (FD) plays essential roles in both the initiation and the amplification loop and circulates as an active form. Mannose-binding lectin-associated serine proteases (MASPs) are key enzymes of the lectin pathway, and MASP-1 and/or MASP-3 are reported to be involved in the activation of FD. In the current study, we generated mice monospecifically deficient for MASP-1 or MASP-3 and found that the sera of the MASP-1-deficient mice lacked lectin pathway activity, but those of the MASP-3-deficient mice lacked alternative pathway activity with a zymogen FD. Furthermore, the results indicate that MASP-3 but not MASP-1 activates the zymogen FD under physiological conditions and MASP-3 circulates predominantly as an active form. Therefore, our study illustrates that, in mice, MASP-3 orchestrates the overall complement reaction through the activation of FD.
Assuntos
Fator D do Complemento/imunologia , Via Alternativa do Complemento/imunologia , Proteínas do Sistema Complemento/imunologia , Serina Proteases Associadas a Proteína de Ligação a Manose/imunologia , Animais , Ativação do Complemento/imunologia , Lectina de Ligação a Manose da Via do Complemento/imunologia , Feminino , Sistema Imunitário/imunologia , Lectinas/imunologia , Camundongos , Camundongos Endogâmicos C57BLRESUMO
In recent years, the number of patients with osteoporosis has increased as population grows older. Therefore, the chemoprevention of osteoporosis by better nutrition is important. White-rot fungi degrades milled wood lignin for growth and development. This degradation results in the formation of phenolic compounds such as syringic acid (SA) and vanillic acid (VA). In the artificial culture of edible mushrooms using a mushroom bed, the disposal of waste beds after mushroom cultivation is an important issue. The present study investigated the presence and amount of both SA and VA in the discarded waste beds after mushroom cultivation. The extracts from waste beds after cultivation of shiitake mushrooms, Lentinula edodes; buna shimeji, Hypsizygus marmoreus; maitake, Grifola frondosa; king trumpet mushrooms, Pleurotus eryngii; and butterscotch mushrooms, Pholiota microspora were analyzed using high performance liquid chromatography. Although the content of SA and VA was considerably different among the mushrooms, SA and VA were present in extracts obtained from all the waste beds. We also demonstrated that SA and VA exert their anti-osteoporotic effect independently of the estrogen receptor-mediated pathway using murine monocytic RAW264.7 cells, ovariectomized mice, and human breast cancer MCF-7 cells. Thus, these results suggest that the extracts are effective sources of SA and VA, which are effective in preventing osteoporosis.
Assuntos
Agaricales/química , Ácido Gálico/análogos & derivados , Osteoporose/tratamento farmacológico , Ácido Vanílico/farmacologia , Animais , Linhagem Celular , Ácido Gálico/química , Ácido Gálico/farmacologia , Humanos , Camundongos , Ácido Vanílico/químicaRESUMO
The development of neuroprotective agents is necessary for the treatment of neurodegenerative diseases. Here, we report PQA-11, a prenylated quinolinecarboxylic acid (PQA) derivative, as a potent neuroprotectant. PQA-11 inhibits glutamate-induced cell death and caspase-3 activation in hippocampal cultures, as well as inhibits N-Methyl-4-phenylpyridinium iodide- and amyloid ß1-42-induced cell death in SH-SY5Y cells. PQA-11 also suppresses mitogen-activated protein kinase kinase 4 (MKK4) and c-jun N-terminal kinase (JNK) signaling activated by these neurotoxins. Quartz crystal microbalance analysis and in vitro kinase assay reveal that PQA-11 interacts with MKK4, and inhibits its sphingosine-induced activation. The administration of PQA-11 by intraperitoneal injection alleviates 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced degeneration of nigrostriatal dopaminergic neurons in mice. These results suggest that PQA-11 is a unique MKK4 inhibitor with potent neuroprotective effects in vitro and in vivo. PQA-11 may be a valuable lead for the development of novel neuroprotectants.
Assuntos
Ácidos Carboxílicos/farmacologia , MAP Quinase Quinase 4/antagonistas & inibidores , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Prenilação/efeitos dos fármacos , Quinolinas/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Linhagem Celular Tumoral , Humanos , MAP Quinase Quinase 4/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Prenilação/fisiologiaRESUMO
Phospholipase C (PLC)-δ1, activated by p122RhoGTPase-activating protein (GAP)/deleted in liver cancer-1 (p122RhoGAP/DLC-1), contributes to the coronary spastic angina (CSA) pathogenesis. The present study aims to further investigate the p122RhoGAP/DLC-1 protein. We examined molecules assisting this protein and identified a scaffold protein-IQ motif-containing GTPase-activating protein 1 (IQGAP1). IQGAP1-C binds to the steroidogenic acute regulatory-related lipid transfer (START) domain of p122RhoGAP/DLC-1, and PLC-δ1 binds to IQGAP1-N, forming a complex. In fluorescence microscopy, small dots of PLC-δ1 created fine linear arrays like microtubules, and IQGAP1 and p122RhoGAP/DLC-1 were colocated in the cytoplasm with PLC-δ1. Ionomycin induced the raft recruitment of the PLC-δ1, IQGAP1, and p122RhoGAP/DLC-1 complex by translocation to the plasma membrane (PM), indicating the movement of this complex is along microtubules with the motor protein kinesin. Moreover, the IQGAP1 protein was elevated in skin fibroblasts obtained from patients with CSA, and it enhanced the PLC activity and peak intracellular calcium concentration in response to acetylcholine. IQGAP1, a novel stimulating protein, forms a complex with p122RhoGAP/DLC-1 and PLC-δ1 that moves along microtubules and enhances the PLC activity.
RESUMO
The pathophysiology of benign prostatic hyperplasia (BPH) remained unclear. Here, we concentrated on the complement activation in the growth of BPH using a rat model. BPH tissues were harvested from rats after rat urogenital sinus implantation. The local expression and deposition levels of C1q, C3, mannose-binding lectin (MBL), factor B (FB), and C5b-9 in the rat and human BPH tissues were analyzed by real-time RT-PCR, western blotting and immunohistochemistry (IHC). Serum IgG levels in the rat BPH model were analyzed by ELISA, and IHC was used to assess tissue localization. Proteins binding serum IgG autoantibody in the BPH rats were isolated by immunoprecipitation. C1q, C3, MBL, FB and C5b-9 were highly localized in rat BPH tissues compared to normal tissues. In contrast, C3, FB and C5b-9, but not C1q and MBL, were abundantly detected in human BPH tissues compared to normal tissues. Diffuse localization of IgG in rat BPH tissues was found. Heat shock protein 90, annexin, α-smooth muscle actin, and ß-actin were identified as targets for IgG autoantibodies in the BPH model. Our results strongly suggested the role for complement activation in the growth process of BPH, likely triggered by classical pathway activation with autoantibodies.
Assuntos
Autoantígenos/imunologia , Ativação do Complemento/imunologia , Proteínas do Sistema Complemento/imunologia , Suscetibilidade a Doenças , Hiperplasia Prostática/etiologia , Animais , Autoanticorpos/imunologia , Proteínas do Sistema Complemento/genética , Proteínas do Sistema Complemento/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças/imunologia , Humanos , Imunoglobulina G/imunologia , Masculino , Modelos Biológicos , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patologia , RatosRESUMO
Reactive oxygen species (ROS) are implicated in the modulation of diverse processes including immune responses. To evaluate the effects of metabolic ROS produced by mitochondria on B-cell function and development, we created transgenic (Tg) mice expressing a phosphorylation-defective mutant of succinate dehydrogenase A in B cells (bSDHAY215F ). Splenic B cells in male, but not female, bSDHAY215F mice produced three times more ROS than those in the control mice, and had decreased production of IgM, IgG1 , and IgG3 , and affinity maturation of IgG1 against T-cell-dependent antigens. Following immunization, the male bSDHAY215F mice further displayed suppressed germinal center (GC) formation, and proliferation of GC B cells. Signaling analysis revealed defects in the intrinsic BCR responses, such as activation of Lyn, Btk, and PLCγ2, thus resulting in reduced intracellular Ca2+ mobilization. Notably, the expression levels of B-cell co-receptor CD19 and its interaction with Lyn after BCR ligation were significantly reduced in B cells from male bSDHAY215F mice. These results suggest that mitochondrial ROS suppress humoral immune responses through reduction of CD19 expression and resultant BCR signaling in B cells. Therefore, B-cell immunity may be more labile to oxidative stress in male mice than in female mice.
Assuntos
Antígenos CD19/metabolismo , Linfócitos B/imunologia , Complexo II de Transporte de Elétrons/metabolismo , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antígenos CD19/genética , Células Cultivadas , Complexo II de Transporte de Elétrons/genética , Feminino , Imunidade Humoral , Terapia de Imunossupressão , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Fosforilação/genética , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais/genéticaRESUMO
Development of new immunosuppressing agents is necessary in organ transplantation or immune diseases. Because Ppc-1 exhibits a suppressing effect on interleukin-2 (IL2) production in Jurkat cells, we synthesized and screened Ppc-1 derivatives that preserve prenylated quinolinecarboxylic acid (PQA) structure, and identified compound 18 (PQA-18) as a novel molecule with immunosuppressing effect. PQA-18 suppressed not only IL2 but also IL4, IL6, and tumor necrosis factor-α production in human peripheral lymphocytes without affecting cell viability. Two-dimensional gel electrophoresis analysis and in vitro kinase assay revealed that PQA-18 inhibits kinase activity of p21-activated kinase 2 (PAK2). Administration of PQA-18 by intraperitoneal injection suppressed the population of a subset of regulatory T cells and the immunoglobulin (Ig) production against T cell-dependent antigens in mice. Treatment with the PQA-18 ointment on Nc/Nga mice, a model of human atopic dermatitis, improved skin lesions and serum IgE levels. These results suggest that PQA-18 is a unique PAK2 inhibitor with potent immunosuppressing effects in vitro and in vivo. PQA-18 may be a valuable lead for the development of novel immunosuppressants.
Assuntos
Ácidos Carboxílicos/farmacologia , Imunidade Celular/fisiologia , Imunossupressores/farmacologia , Prenilação/fisiologia , Quinolinas/farmacologia , Quinases Ativadas por p21/metabolismo , Animais , Ácidos Carboxílicos/química , Dermatite/tratamento farmacológico , Dermatite/imunologia , Dermatite/metabolismo , Relação Dose-Resposta a Droga , Humanos , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/imunologia , Células Jurkat , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Prenilação/efeitos dos fármacos , Prenilação/imunologia , Quinolinas/química , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Ácidos Tri-Iodobenzoicos/farmacologia , Quinases Ativadas por p21/antagonistas & inibidores , Quinases Ativadas por p21/imunologiaRESUMO
BACKGROUND: We previously showed that phospholipase C (PLC)-δ1 activity was enhanced by 3-fold in patients with coronary spastic angina (CSA). We also reported that p122Rho GTPase-activating protein/deleted in liver cancer-1 (p122RhoGAP/DLC-1) protein, which was discovered as a PLC-δ1 stimulator, was upregulated in CSA patients. We tested the hypothesis that p122RhoGAP/DLC-1 overexpression causes coronary spasm. METHODS AND RESULTS: We generated transgenic (TG) mice with vascular smooth muscle (VSM)-specific overexpression of p122RhoGAP/DLC-1. The gene and protein expressions of p122RhoGAP/DLC-1 were markedly increased in the aorta of homozygous TG mice. Stronger staining with anti-p122RhoGAP/DLC-1 in the coronary artery was found in TG than in WT mice. PLC activities in the plasma membrane fraction and the whole cell were enhanced by 1.43 and 2.38 times, respectively, in cultured aortic vascular smooth muscle cells from homozygous TG compared with those from WT mice. Immediately after ergometrine injection, ST-segment elevation was observed in 1 of 7 WT (14%), 6 of 7 heterozygous TG (84%), and 7 of 7 homozygous TG mice (100%) (p<0.05, WT versus TGs). In the isolated Langendorff hearts, coronary perfusion pressure was increased after ergometrine in TG, but not in WT mice, despite of the similar response to prostaglandin F2α between TG and WT mice (n = 5). Focal narrowing of the coronary artery after ergometrine was documented only in TG mice. CONCLUSIONS: VSM-specific overexpression of p122RhoGAP/DLC-1 enhanced coronary vasomotility after ergometrine injection in mice, which is relevant to human CSA.
Assuntos
Vasoespasmo Coronário/metabolismo , Vasos Coronários/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Músculo Liso Vascular/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Angina Pectoris/metabolismo , Animais , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Regulação para Cima/fisiologiaRESUMO
Osteosarcoma is a common metastatic bone cancer that predominantly develops in children and adolescents. Metastatic osteosarcoma remains associated with a poor prognosis; therefore, more effective anti-metastatic drugs are needed. Differentiation-inducing factor-1 (DIF-1), -2, and -3 are novel lead anti-tumor agents that were originally isolated from the cellular slime mold Dictyostelium discoideum. Here we investigated the effects of a panel of DIF derivatives on lysophosphatidic acid (LPA)-induced migration of mouse osteosarcoma LM8 cells by using a Boyden chamber assay. Some DIF derivatives such as Br-DIF-1, DIF-3(+2), and Bu-DIF-3 (5-20 µM) dose-dependently suppressed LPA-induced cell migration with associated IC50 values of 5.5, 4.6, and 4.2 µM, respectively. On the other hand, the IC50 values of Br-DIF-1, DIF-3(+2), and Bu-DIF-3 versus cell proliferation were 18.5, 7.2, and 2.0 µM, respectively, in LM8 cells, and >20, 14.8, and 4.3 µM, respectively, in mouse 3T3-L1 fibroblasts (non-transformed). Together, our results demonstrate that Br-DIF-1 in particular may be a valuable tool for the analysis of cancer cell migration, and that DIF derivatives such as DIF-3(+2) and Bu-DIF-3 are promising lead anti-tumor agents for the development of therapies that suppress osteosarcoma cell proliferation, migration, and metastasis.
Assuntos
Movimento Celular/efeitos dos fármacos , Dictyostelium/metabolismo , Hexanonas/farmacologia , Lisofosfolipídeos/farmacologia , Osteossarcoma/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Camundongos , Mitocôndrias/efeitos dos fármacos , Osteossarcoma/patologia , Consumo de Oxigênio/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Anomalous atmospheric variations in radon related to earthquakes have been observed in hourly exhaust-monitoring data from radioisotope institutes in Japan. The extraction of seismic anomalous radon variations would be greatly aided by understanding the normal pattern of variation in radon concentrations. Using atmospheric daily minimum radon concentration data from five sampling sites, we show that a sinusoidal regression curve can be fitted to the data. In addition, we identify areas where the atmospheric radon variation is significantly affected by the variation in atmospheric turbulence and the onshore-offshore pattern of Asian monsoons. Furthermore, by comparing the sinusoidal regression curve for the normal annual (seasonal) variations at the five sites to the sinusoidal regression curve for a previously published dataset of radon values at the five Japanese prefectures, we can estimate the normal annual variation pattern. By fitting sinusoidal regression curves to the previously published dataset containing sites in all Japanese prefectures, we find that 72% of the Japanese prefectures satisfy the requirements of the sinusoidal regression curve pattern. Using the normal annual variation pattern of atmospheric daily minimum radon concentration data, these prefectures are suitable areas for obtaining anomalous radon variations related to earthquakes.
Assuntos
Poluentes Radioativos do Ar/análise , Monitoramento de Radiação , Radônio/análise , Terremotos , Japão , Modelos Teóricos , Estações do AnoRESUMO
Mitochondria play a key role in diverse processes including ATP synthesis and apoptosis. Mitochondrial function can be studied using inhibitors of respiration, and new agents are valuable for discovering novel mechanisms involved in mitochondrial regulation. Here, we screened small molecules derived from slime molds and other microorganisms for their effects on mitochondrial oxygen consumption. We identified Ppc-1 as a novel molecule which stimulates oxygen consumption without adverse effects on ATP production. The kinetic behavior of Ppc-1 suggests its function as a mitochondrial uncoupler. Serial administration of Ppc-1 into mice suppressed weight gain with no abnormal effects on liver or kidney tissues, and no evidence of tumor formation. Serum fatty acid levels were significantly elevated in mice treated with Ppc-1, while body fat content remained low. After a single administration, Ppc-1 distributes into various tissues of individual animals at low levels. Ppc-1 stimulates adipocytes in culture to release fatty acids, which might explain the elevated serum fatty acids in Ppc-1-treated mice. The results suggest that Ppc-1 is a unique mitochondrial regulator which will be a valuable tool for mitochondrial research as well as the development of new drugs to treat obesity.
Assuntos
Dictyosteliida/metabolismo , Mitocôndrias/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Redução de Peso/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Ácidos Graxos/metabolismo , Feminino , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Mitocôndrias/metabolismo , Consumo de Oxigênio/efeitos dos fármacosRESUMO
Anomalous radon readings in air have been reported before an earthquake activity. However, careful measurements of atmospheric radon concentrations during a normal period are required to identify anomalous variations in a precursor period. In this study, we obtained radon concentration data for 5 years (2003-2007) that can be considered a normal period and compared it with data from the precursory period of 2008 until March 2011, when the 2011 Tohoku-Oki Earthquake occurred. Then, we established a model for seasonal variation by fitting a sinusoidal model to the radon concentration data during the normal period, considering that the seasonal variation was affected by atmospheric turbulence. By determining the amplitude in the sinusoidal model, the normal variation of the radon concentration can be estimated. Thus, the results of this method can be applied to identify anomalous radon variations before an earthquake.
Assuntos
Modelos Teóricos , Monitoramento de Radiação/métodos , Radônio/análise , Estações do AnoRESUMO
Mitochondrial uncoupling is one of the therapeutic strategies used to control energy metabolism in various metabolic diseases and in obesity. Ppc-1 (1), a prenylated quinolinecarboxylic acid isolated from cellular slime molds, shows uncoupling activity in vitro and anti-obesity activity in vivo. In this study, we synthesized Ppc-1 (1) and its derivatives, and revealed the structure-activity relationship of uncoupling activities. The triprenylated compound 18 showed mitochondrial uncoupling activity that was more potent than that of Ppc-1 (1). Compound 18 also suppressed weight gain in mice without undesired effects such as lesions on tissues. These results indicate that compound 18 could be used as a seed compound for new anti-obesity drugs.