RESUMO
BACKGROUND: New strategies are needed to combat multidrug-resistant bacteria. The restriction of iron uptake by bacteria is a promising way to inhibit their growth. We aimed to suppress the growth of Vibrio bacterial species by inhibiting their ferric ion-binding protein (FbpA) using food components. METHODS: Twenty spices were selected for the screening of FbpA inhibitors. The candidate was applied to antibacterial tests, and the mechanism was further studied. RESULTS: An active compound, rosmarinic acid (RA), was screened out. RA binds competitively and more tightly than Fe3+ to VmFbpA, the FbpA from V. metschnikovii, with apparent KD values of 8 µM vs. 17 µM. Moreover, RA can inhibit the growth of V. metschnikovii to one-third of the control at 1000 µM. Interestingly, sodium citrate (SC) enhances the growth inhibition effect of RA, although SC only does not inhibit the growth. The combination of RA/SC completely inhibits the growth of not only V. metschnikovii at 100/100 µM but also the vibriosis-causative pathogens V. vulnificus and V. parahaemolyticus, at 100/100 and 1000/100 µM, respectively. However, RA/SC does not affect the growth of Escherichia coli. CONCLUSIONS: RA/SC is a potential bacteriostatic agent against Vibrio species while causing little damage to indigenous gastrointestinal bacteria.
Assuntos
Cinamatos/farmacologia , Depsídeos/farmacologia , Ferro/metabolismo , Citrato de Sódio/farmacologia , Vibrio parahaemolyticus/efeitos dos fármacos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Cinamatos/química , Cinamatos/metabolismo , Depsídeos/química , Depsídeos/metabolismo , Sinergismo Farmacológico , Proteínas de Ligação ao Ferro/química , Proteínas de Ligação ao Ferro/metabolismo , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Ligação Proteica , Vibrio parahaemolyticus/metabolismo , Ácido RosmarínicoRESUMO
Cortical computation is distributed across multiple areas of the cortex by networks of reciprocal connectivity. However, how such connectivity contributes to the communication between the connected areas is not clear. In this study, we examine the communication between sensory and motor cortices. We develop an eye movement task in mice and combine it with optogenetic suppression and two-photon calcium imaging techniques. We identify a small region in the secondary motor cortex (MOs) that controls eye movements and reciprocally connects with a rostrolateral part of the higher visual areas (VRL/A/AL). These two regions encode both motor signals and visual information; however, the information flow between the regions depends on the direction of the connectivity: motor information is conveyed preferentially from the MOs to the VRL/A/AL, and sensory information is transferred primarily in the opposite direction. We propose that reciprocal connectivity streamlines information flow, enhancing the computational capacity of a distributed network.
Assuntos
Córtex Cerebral/fisiologia , Movimentos Oculares/fisiologia , Córtex Motor/fisiologia , Rede Nervosa/fisiologia , Animais , Mapeamento Encefálico , Humanos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios Motores/fisiologia , Estimulação Luminosa/métodos , Desempenho Psicomotor/fisiologia , Células Receptoras Sensoriais/fisiologia , Córtex Somatossensorial/fisiologiaRESUMO
During a routine health examination, a 50-year-old man was found to have an elevated lesion at the esophagogastric junction. Poorly differentiated adenocarcinoma was diagnosed from the biopsy findings. Computed tomography showed metastases in the mediastinal, intra-abdominal, and paraaortic lymph nodes. The clinical stage diagnosis was cT2, cN4, cM0, cStage IVa. Combination chemotherapy with docetaxel, CDDP, and 5-FU (DCF) was started initially. After 2 courses of DCF, the primary lesion and mediastinal lymph nodes had decreased in size, but the intra-abdominal lymph node had grown. A curative operation with paraaortic lymph node dissection was considered possible; thus, video-assisted thoracoscopic surgery of the esophagus with 3-field lymph node dissection was performed. The final findings revealed Barrett's esophageal carcinoma, EG, 0-III,23×18 mm, mod-por, CT-pT1b (sm3) pN4, sM0, fStage IV. Histologically, the mediastinal lymph node metastases disappeared with chemotherapy, but no reduction was observed in the abdominal lymph nodes. After surgery, 2 courses of combination adjuvant chemotherapy with CDDP and 5-FU were administered along with 50 Gy of radiotherapy. Subsequently, the treatment was changed to tegafur-gimeracil-oteracil potassium alone on an outpatient basis. The patient remains recurrence free 22 months postsurgery.
Assuntos
Esôfago de Barrett/terapia , Quimiorradioterapia , Neoplasias Esofágicas/terapia , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Esôfago de Barrett/patologia , Cisplatino/administração & dosagem , Docetaxel , Neoplasias Esofágicas/patologia , Fluoruracila/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Taxoides/administração & dosagemRESUMO
Increasing incidence of small intestinal ulcers associated with nonsteroidal anti-inflammatory drugs (NSAIDs) has become a topic with recent advances of endoscopic technology. However, the pathogenesis and therapy are not fully understood. The aim of this study is to examine the effect of Rikkunshito (TJ-43), a traditional herbal medicine, on expression of HSP60 and cytoprotective ability in small intestinal cell line (IEC-6). Effect of TJ-43 on HSP60 expression in IEC-6 cells was evaluated by immunoblot analysis. The effect of TJ-43 on cytoprotective abilities of IEC-6 cells against hydrogen peroxide or indomethacin was studied by MTT assay, LDH-release assay, caspase-8 activity, and TUNEL. HSP60 was significantly induced by TJ-43. Cell necrosis and apoptosis were significantly suppressed in IEC-6 cells pretreated by TJ-43 with overexpression of HSP60. Our results suggested that HSP60 induced by TJ-43 might play an important role in protecting small intestinal epithelial cells from apoptosis and necrosis in vitro.
RESUMO
Nobiletin, a compound of polymethoxy flavones found in citrus fruits, possesses a wide range of pharmacological activities. Here we report the effects of nobiletin on catecholamine secretion in cultured bovine adrenal medullary cells. Nobiletin (1.0-100 microM) concentration-dependently stimulated catecholamine secretion and (45)Ca(2+) influx. Its stimulatory effect of nobiletin on catecholamine secretion was abolished by deprivation of extracellular Ca(2+) and partially inhibited by specific inhibitors of voltage-dependent Ca(2+) channels and Na(+)/Ca(2+) exchangers. On the other hand, nobiletin suppressed catecholamine secretion and (22)Na(+) and (45)Ca(2+) influx induced by acetylcholine, an agonist of nicotinic acetylcholine receptors, in a concentration-dependent manner. It also inhibited catecholamine secretion, (22)Na(+) influx and/or (45)Ca(2+) influx induced by veratridine, an activator of voltage-dependent Na(+) channels, and 56 mM K(+), an activator of voltage-dependent Ca(2+) channels. In Xenopus oocytes expressing alpha3beta4 neuronal acetylcholine receptors, nobiletin directly inhibited the current evoked by acetylcholine in a concentration-dependent manner similar to that observed in catecholamine secretion. The present findings suggest that nobiletin, by itself, stimulates catecholamine secretion via activation of voltage-dependent Ca(2+) channels or Na(+)/Ca(2+) exchangers, whereas it inhibits catecholamine secretion induced by acetylcholine through the suppression of Na(+) influx and Ca(2+) influx in cultured bovine adrenal medullary cells.
Assuntos
Medula Suprarrenal/efeitos dos fármacos , Medula Suprarrenal/metabolismo , Catecolaminas/metabolismo , Células Cromafins/efeitos dos fármacos , Células Cromafins/metabolismo , Citrus/química , Flavonas/farmacologia , Medula Suprarrenal/inervação , Animais , Antioxidantes/farmacologia , Cálcio/antagonistas & inibidores , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Catecolaminas/antagonistas & inibidores , Bovinos , Células Cultivadas , Relação Dose-Resposta a Droga , Oócitos , Extratos Vegetais/farmacologia , Canais de Sódio/metabolismo , Trocador de Sódio e Cálcio/antagonistas & inibidores , Trocador de Sódio e Cálcio/metabolismo , XenopusRESUMO
We investigated in this study the anti-obesity effect of an extract of Petasites japonicus (a culinary vegetable from Eastern Asia) on a murine adipocyte cell line (3T3-L1) and on diet-induced obesity-prone mice. An ethanol extract of P. japonicus. (PJET) suppressed 3T3-L1 preadipocyte differentiation; however, a hot water extract of P. japonicus (PJHW) exhibited no effect on cell differentiation. PJET significantly attenuated three adipogenetic transcription factors, peroxisome proliferator-activated receptor gamma2, CCAAT/enhancer-binding protein and sterol regulatory element-binding protein 1C, at the mRNA level and suppressed the gene expression of fatty acid synthetase. An experiment with diet-induced obesity-prone C57BL/6J mice showed that PJET lowered the body weight gain and visceral fat tissue accumulation, and ameliorated the plasma cholesterol concentration. These findings suggest that P. japonicus might be an effective food against obesity.
Assuntos
Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Fármacos Antiobesidade/farmacologia , Obesidade/metabolismo , Petasites/química , Extratos Vegetais/farmacologia , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/fisiologia , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Colesterol/sangue , Gorduras na Dieta/administração & dosagem , Ácido Graxo Sintases/metabolismo , Gordura Intra-Abdominal/efeitos dos fármacos , Gordura Intra-Abdominal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , PPAR gama/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismoRESUMO
We examined the effects of genistein, one of the major soy phytoestrogens, on the activity of noradrenaline transporter (NAT) and serotonin transporter. Treatment with genistein (10 nM-10 microM) for 20 min stimulated [(3)H]noradrenaline (NA) uptake by SK-N-SH cells. Genistein also stimulated [(3)H]NA uptake and [(3)H]serotonin uptake by NAT and serotonin transporter transiently transfected COS-7 cells, respectively. Kinetics analysis of the effect of genistein on NAT activity in NAT-transfected COS-7 cells revealed that genistein significantly increased the maximal velocity of NA transport with little or no change in the affinity. Scatchard analysis of [(3)H]nisoxetine binding to NAT-transfected COS-7 cells showed that genistein increased the maximal binding without altering the dissociation constant. Although genistein is also known to be an inhibitor of tyrosine kinases, daidzein, another soy phytoestrogen and an inactive genistein analogue against tyrosine kinases, had little effect on [(3)H]NA uptake by SK-N-SH cells. The stimulatory effects on NAT activity were observed by treatment of tyrphostin 25, an inhibitor of epidermal growth factor receptor tyrosine kinase, whereas orthovanadate, a protein tyrosine phosphatase inhibitor, suppressed [(3)H]NA uptake by NAT-transfected COS-7 cells. These findings suggest that genistein up-regulates the activity of neuronal monoamine transporters probably through processes involving protein tyrosine phosphorylation.
Assuntos
Genisteína/farmacologia , Glycine max/química , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/efeitos dos fármacos , Fitoestrógenos/farmacologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/efeitos dos fármacos , Animais , Células COS , Linhagem Celular Tumoral , Chlorocebus aethiops , Inibidores Enzimáticos/farmacologia , Estradiol/análogos & derivados , Estradiol/farmacologia , Fluoxetina/análogos & derivados , Fluoxetina/metabolismo , Fulvestranto , Humanos , Neuroblastoma , Norepinefrina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/genética , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/fisiologia , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Receptores de Estrogênio/antagonistas & inibidores , Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/fisiologia , Transfecção , Trítio , Vanadatos/farmacologiaRESUMO
AIMS: The aim of this study is to investigate the expression and cytoprotective function of a 72-kDa heat shock protein (HSP72) using a reflux esophagitis model in rats. MAIN METHODS: Expression of HSP60, HSP72, and HSP90 in rat esophageal mucosa was evaluated by Western blot analysis before and after hyperthermia (42.5 degrees C, 20 min). Rats received the operation to produce reflux esophagitis with or without pretreatment with hyperthermia to induce HSPs. The esophageal mucosal damage was evaluated 12 h after the operation. KEY FINDINGS: Expression of HSP72 was significantly increased by hyperthermia in rat esophageal mucosa. Reflux esophagitis was dramatically prevented when HSP72 was preinduced by hyperthermia. Furthermore, activation of TNF-alpha and IL-1beta in esophageal mucosa was also suppressed. SIGNIFICANCE: These results suggested that hyperthermia protects the esophageal mucosa in reflux esophagitis model by inducing HSP72 and suppressing proinflammatory cytokine activation. These findings might suggest that HSP-inducing therapy could be a novel and unique therapy for reflux esophagitis.
Assuntos
Esofagite Péptica/metabolismo , Esofagite Péptica/prevenção & controle , Proteínas de Choque Térmico HSP72/biossíntese , Hipertermia Induzida , Mucosa/metabolismo , Animais , Western Blotting , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Garlic has been reported to have chemopreventive effects against a variety of cancers. However, different garlic preparations contain different constituents. We investigated the chemopreventive effect of aged garlic extract (AGE), an odorless product from prolonged extraction of fresh garlic, on colon carcinogenesis and cell proliferation in 1,2-dimethylhydrazine (DMH)-induced colon neoplastic rats. Rats were given weekly subcutaneous injections of DMH (20 mg/kg) for 20 wk, and fed either a basal diet or one containing 4% AGE. Serum from AGE-treated rats contained detectable S-allylcysteine. The AGE diet significantly reduced the number of colon tumors and aberrant crypt foci compared to the basal diet. Cell proliferation of normal-appearing colonic mucosa was assessed by MIB-5 immunohistochemistry. AGE treatment significantly decreased the mean MIB-5-labeling index. These findings suggest AGE has a chemopreventive effect on colon carcinogenesis through suppression of cell proliferation.