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1.
Invest New Drugs ; 40(2): 255-264, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34816337

RESUMEN

Introduction Boron neutron capture therapy (BNCT) is a biologically targeted, cell-selective particle irradiation therapy that utilizes the nuclear capture reaction of boron and neutron. Recently, accelerator neutron generators have been used in clinical settings, and expectations for developing new boron compounds are growing. Methods and Results In this study, we focused on serum albumin, a well-known drug delivery system, and developed maleimide-functionalized closo-dodecaborate albumin conjugate (MID-AC) as a boron carrying system for BNCT. Our biodistribution experiment involved F98 glioma-bearing rat brain tumor models systemically administered with MID-AC and demonstrated accumulation and long retention of boron. Our BNCT study with MID-AC observed statistically significant prolongation of the survival rate compared to the control groups, with results comparable to BNCT study with boronophenylalanine (BPA) which is the standard use of in clinical settings. Each median survival time was as follows: untreated control group; 24.5 days, neutron-irradiated control group; 24.5 days, neutron irradiation following 2.5 h after termination of intravenous administration (i.v.) of BPA; 31.5 days, and neutron irradiation following 2.5 or 24 h after termination of i.v. of MID-AC; 33.5 or 33.0 days, respectively. The biological effectiveness factor of MID-AC for F98 rat glioma was estimated based on these survival times and found to be higher to 12. This tendency was confirmed in BNCT 24 h after MID-AC administration. Conclusion MID-AC induces an efficient boron neutron capture reaction because the albumin contained in MID-AC is retained in the tumor and has a considerable potential to become an effective delivery system for BNCT in treating high-grade gliomas.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Neoplasias Encefálicas , Glioma , Albúminas , Animales , Boro/uso terapéutico , Compuestos de Boro/uso terapéutico , Terapia por Captura de Neutrón de Boro/métodos , Neoplasias Encefálicas/tratamiento farmacológico , Glioma/patología , Humanos , Maleimidas , Ratas , Distribución Tisular
2.
Jpn J Clin Oncol ; 52(5): 433-440, 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35079791

RESUMEN

BACKGROUND: Although boron neutron capture therapy has shown excellent survival data, previous studies have shown an increase in radiation necrosis against recurrent malignant glioma. Herein, we proposed that bevacizumab may reduce radiation injury from boron neutron capture therapy by re-irradiation. We evaluated the efficacy and safety of a boron neutron capture therapy and add-on bevacizumab combination therapy in patients with recurrent malignant glioma. METHODS: Patients with recurrent malignant glioma were treated with reactor-based boron neutron capture therapy. Treatment with bevacizumab (10 mg/kg) was initiated 1-4 weeks after boron neutron capture therapy and was administered every 2-3 weeks until disease progression. Initially diagnosed glioblastomas were categorized as primary glioblastoma, whereas other forms of malignant glioma were categorized as non-primary glioblastoma. RESULTS: Twenty-five patients (14 with primary glioblastoma and 11 with non-primary glioblastoma) were treated with boron neutron capture therapy and add-on bevacizumab. The 1-year survival rate for primary glioblastoma and non-primary glioblastoma was 63.5% (95% confidence interval: 33.1-83.0) and 81.8% (95% confidence interval: 44.7-95.1), respectively. The median overall survival was 21.4 months (95% confidence interval: 7.0-36.7) and 73.6 months (95% confidence interval: 11.4-77.2) for primary glioblastoma and non-primary glioblastoma, respectively. The median progression-free survival was 8.3 months (95% confidence interval: 4.2-12.1) and 15.6 months (95% confidence interval: 3.1-29.8) for primary glioblastoma and non-primary glioblastoma, respectively. Neither pseudoprogression nor radiation necrosis were identified during bevacizumab treatment. Alopecia occurred in all patients. Six patients experienced adverse events ≥grade 3. CONCLUSIONS: Boron neutron capture therapy and add-on bevacizumab provided a long overall survival and a long progression-free survival in recurrent malignant glioma compared with previous studies on boron neutron capture therapy alone. The add-on bevacizumab may reduce the detrimental effects of boron neutron capture therapy, including pseudoprogression and radiation necrosis. Further studies of the combination therapy with a larger sample size and a randomized controlled design are warranted.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Neoplasias Encefálicas , Glioblastoma , Glioma , Traumatismos por Radiación , Bevacizumab/uso terapéutico , Terapia por Captura de Neutrón de Boro/efectos adversos , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/radioterapia , Glioblastoma/tratamiento farmacológico , Glioblastoma/radioterapia , Glioma/tratamiento farmacológico , Glioma/radioterapia , Humanos , Necrosis/etiología , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/radioterapia , Traumatismos por Radiación/etiología
3.
Support Care Cancer ; 29(8): 4723-4732, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33515108

RESUMEN

PURPOSE: Palonosetron, a long-acting 5-HT3 receptor antagonist, is an effective antiemetic agent for chemotherapy-induced nausea and vomiting; however, it sometimes causes severe constipation. The aim of the present study was to evaluate the severity of palonosetron-related constipation. METHODS: We retrospectively analyzed the incidence and severity of constipation after intravenous administration of 0.75-mg palonosetron in 150 chemotherapy-naïve patients who received first-line chemotherapy at Saga University Hospital. Constipation was classified into grades 1-5 according to the Common Terminology Criteria for Adverse Events version 5.0. Multiple logistic regression analysis was performed to identify factors associated with palonosetron-related worsening of constipation to grade 2 or higher. RESULTS: Palonosetron significantly increased the incidence and severity of constipation (incidence: before vs. after palonosetron, 35.4% vs. 74.0%, p < 0.0001, and severity: before vs. after palonosetron, 26.7% and 8.7% in grades 1 and 2, respectively, vs. 46.7%, 23.3%, and 4.0% in grades 1, 2, and 3, respectively, p < 0.0001). Despite the use of laxatives, 4.0% of patients had grade 3 constipation requiring manual evacuation. Combination treatment with aprepitant (odds ratio (OR), 10.9; 95% confidence interval (CI), 1.3-90.0; p = 0.026) and older age (OR, 1.25; 95% CI, 1.01-1.57; p = 0.039) were factors associated with the severity of constipation. CONCLUSION: Constipation was more severe in patients receiving combination treatment with aprepitant than in those treated with palonosetron alone. Older age was also associated with increased risk of severe palonosetron-related constipation. Identification of risk factors can help target risk-based laxative therapy.


Asunto(s)
Antieméticos/efectos adversos , Estreñimiento/inducido químicamente , Palonosetrón/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
4.
J Pharmacol Exp Ther ; 370(2): 172-181, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31182471

RESUMEN

The GPR40/FFA1 receptor is a G-protein-coupled receptor expressed in the pancreatic islets and enteroendocrine cells. Here, we report the pharmacological profiles of (3S)-3-cyclopropyl-3-{2-[(1-{2-[(2,2-dimethylpropyl)(6-methylpyridin-2-yl)carbamoyl]-5-methoxyphenyl}piperidin-4-yl)methoxy]pyridin-4-yl}propanoic acid (SCO-267), a novel full agonist of GPR40. Ca2+ signaling and insulin and glucagon-like peptide-1 (GLP-1) secretion were evaluated in GPR40-expressing CHO, MIN6, and GLUTag cells. Hormone secretions and effects on fasting glucose were tested in rats. Single or repeated dosing effects were evaluated in neonatally streptozotocin-induced diabetic rats (N-STZ-1.5 rats), diet-induced obese (DIO) rats, and GPR40-knockout (Ffar1-/- ) mice. Treatment with SCO-267 activated Gq signaling in both high- and low-FFAR1-expressing CHO cells, stimulated insulin secretion in MIN6 cells, and induced GLP-1 release in GLUTag cells. When administered to normal rats, SCO-267 increased insulin, glucagon, GLP-1, glucose-dependent insulinotropic peptide, and peptide YY (PYY) secretions under nonfasting conditions. These results show the full agonistic property of SCO-267 against GPR40. Hypoglycemia was not induced in SCO-267-treated rats during the fasting condition. In diabetic N-STZ-1.5 rats, SCO-267 was highly effective in improving glucose tolerance in single and 2-week dosing studies. DIO rats treated with SCO-267 for 2 weeks showed elevated plasma GLP-1 and PYY levels, reduced food intake, and decreased body weight. In wild-type mice, SCO-267 induced GLP-1 secretion, food intake inhibition, and body weight reduction; however, these effects were abolished in Ffar1-/- mice, indicating a GPR40-dependent mechanism. In conclusion, SCO-267 stimulated islet and gut hormone secretion, improved glycemic control in diabetic rats, and decreased body weight in obese rats. These data suggest the therapeutic potential of SCO-267 for the treatment of diabetes and obesity.


Asunto(s)
Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Ciclopropanos/farmacología , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/tratamiento farmacológico , Obesidad/complicaciones , Piperidinas/farmacología , Propionatos/farmacología , Piridinas/farmacología , Receptores Acoplados a Proteínas G/agonistas , Animales , Células CHO , Cricetulus , Ciclopropanos/uso terapéutico , Diabetes Mellitus Experimental/complicaciones , Modelos Animales de Enfermedad , Perros , Ingestión de Alimentos/efectos de los fármacos , Péptido 1 Similar al Glucagón/metabolismo , Humanos , Secreción de Insulina/efectos de los fármacos , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/metabolismo , Masculino , Ratones , Piperidinas/uso terapéutico , Propionatos/uso terapéutico , Piridinas/uso terapéutico , Ratas
5.
Scand J Gastroenterol ; 52(4): 442-449, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27996337

RESUMEN

OBJECTIVE: We wanted to exam the steady-state energy balance by using high-fat diet-induced obese (DIO) rats and mice as models for positive energy balance, and gastric bypassed (GB) rats and gene knockout of muscarinic acetylcholine M3 receptor (M3KO) mice as models for negative energy balance. METHODS: One hundred and thirty-two rats and mice were used. Energy balance was measured by a comprehensive laboratory animal monitoring system. Gene expression was analysed by in situ hybridisation in M3KO mice. RESULTS: DIO rats reached the plateau of body weight 28 weeks after starting high-fat diet (25% heavier than controls), whereas DIO mice reached the plateau after 6 weeks (23% heavier than controls). At the plateau, DIO rats had higher calorie intake during the light phase but not during the dark phase, while mice had the same calorie intake per day as controls. DIO rats and mice had lower energy expenditure (EE) and respiratory exchange ratio (RER) than controls. GB-rats reached the plateau (15% weight loss) 2 weeks after surgery and had the same calorie intake as sham-operated controls. EE, but not RER, was higher in GB rats than controls during the dark phase. The lean M3KO mice (25% lighter than wild-type (WT) mice at the plateau between 6 and 15 months of age) had the same calorie intake but higher EE, RER and hypothalamic mRNA expression of NPY, AgRP and leptin receptor than WT mice. CONCLUSION: When body weight gain or loss reached a plateau, the steady-state energy balance was mainly maintained by EE and/or RER rather than calorie intake.


Asunto(s)
Metabolismo Energético , Obesidad/metabolismo , Obesidad/cirugía , Pérdida de Peso , Animales , Encéfalo/patología , Grasas de la Dieta , Modelos Animales de Enfermedad , Femenino , Derivación Gástrica , Hibridación in Situ , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Obesos , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Receptor Muscarínico M3/genética
6.
Learn Behav ; 45(2): 135-146, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27619982

RESUMEN

The within-trial contrast hypothesis (WTC) provides a more parsimonious explanation for the phenomenon that humans and animals prefer outcomes that follow more effortful events to outcomes that follow less effortful events (Zentall, 2013). We conducted two WTC experiments with human adults. In Experiment 1, we manipulated the difficulty of a preceding event by varying the interresponse time and the limited-hold interval during differential reinforcement with a low response rate schedule, to examine the effect of effort on the preference for the subsequent stimuli. In Experiment 2, we attempted to identify the variables that had affected the results of Experiment 1, by manipulating time as the delay of reinforcement. The results showed preferences based on WTC only when participants made a high rate of incorrect responses in the preceding event, which was used as an index of the strength of individual effort. These results extend the findings of previous human WTC studies and suggest that the difficulty of a task could serve as an aversive event that affects the WTC effect. It is possible that an index based on performance in the preceding event would provide useful information for predicting the contrast effect.


Asunto(s)
Conducta de Elección , Refuerzo en Psicología , Animales , Columbidae , Humanos
7.
J Pharmacol Exp Ther ; 357(1): 217-27, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26813930

RESUMEN

Sulfonylureas (SUs) are widely used insulin secretagogues, but they have adverse effects including hypoglycemia and secondary failure. Fasiglifam/TAK-875, a selective GPR40 agonist, enhances glucose-stimulated insulin secretion and improves hyperglycemia. In the present study, we compared the in vivo glucose-lowering effects of fasiglifam with SUs. The risk of secondary failure of fasiglifam and the efficacy in rats desensitized to SUs were also evaluated. Moreover, we assessed whether fasiglifam was effective when combined with SUs. In diabetic neonatally streptozotocin-induced rats 1.5 days after birth (N-STZ-1.5), oral administrations of fasiglifam (3-30 mg/kg) dose dependently improved glucose tolerance; the effect was greater than that of glibenclamide at maximal effective doses (glucose AUC: fasiglifam, -37.6%; glibenclamide, -12.3%). Although the glucose-lowering effects of glibenclamide (10 mg/kg/day) were completely diminished in N-STZ-1.5 rats after 4 weeks of treatment, effects were maintained in rats receiving fasiglifam (10 mg/kg/day), even after 15 weeks. Fasiglifam (3-10 mg/kg) was still effective in two models desensitized to SUs: 15-week glibenclamide-treated N-STZ-1.5 rats and aged Zucker diabetic fatty (ZDF) rats. Acute administration of fasiglifam (3 mg/kg) and glimepiride (10 mg/kg) in combination additively decreased glucose AUC (fasiglifam, -25.3%; glimepiride, -20.0%; combination, -43.1%). Although glimepiride (10 mg/kg) decreased plasma glucose below normal in nonfasted control rats, fasiglifam (3 mg/kg) maintained normoglycemia, and no further exaggeration of hypoglycemia was observed with combination treatment. These results indicate that GPR40 agonists could be more effective and durable than SUs. Our results also provide new insights into GPR40 pharmacology and rationale for the use of GPR40 agonists in diabetic patients with SU failure.


Asunto(s)
Benzofuranos/farmacología , Hiperglucemia/tratamiento farmacológico , Hipoglucemiantes/farmacología , Receptores Acoplados a Proteínas G/agonistas , Sulfonas/farmacología , Compuestos de Sulfonilurea/farmacología , Animales , Glucemia/metabolismo , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/tratamiento farmacológico , Sinergismo Farmacológico , Prueba de Tolerancia a la Glucosa , Gliburida/uso terapéutico , Hiperglucemia/sangre , Masculino , Ratas , Ratas Zucker
8.
Nitric Oxide ; 46: 157-64, 2015 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-25460323

RESUMEN

Hydrogen sulfide (H2S) is known to be an important gaseous mediator that affects various functions under physiological and pathological conditions. We examined the effects of NaHS, a H2S donor, on HCO3(-) secretion in rat stomachs and investigated the mechanism involved in this response. Under urethane anesthesia, rat stomachs were mounted on an ex vivo chamber and perfused with saline. Acid secretion had been inhibited by omeprazole. The secretion of HCO3(-) was measured at pH 7.0 using a pH-stat method and by the addition of 10 mM HCl. NaHS (0.5-10 mM) was perfused in the stomach for 5 min. Indomethacin or L-NAME was administered s.c. before NaHS treatment, while glibenclamide (a KATP channel blocker), ONO-8711 (an EP1 antagonist), or propargylglycine (a cystathionine γ-lyase inhibitor) was given i.p. before. The mucosal perfusion of NaHS dose-dependently increased the secretion of HCO3(-), and this effect was significantly attenuated by indomethacin, L-NAME, and sensory deafferentation, but not by glibenclamide or ONO-8711. The luminal output of nitric oxide, but not the mucosal production of prostaglandin E2, was increased by the perfusion of NaHS. Mucosal acidification stimulated HCO3(-) secretion, and this response was inhibited by sensory deafferentation, indomethacin, L-NAME, and ONO-8711, but not by propargylglycine. These results suggested that H2S increased HCO3(-) secretion in the stomach, and this effect was mediated by capsaicin-sensitive afferent neurons and dependent on nitric oxide and prostaglandins, but not ATP-sensitive K(+) channels. Further study is needed to define the role of endogenous H2S in the mechanism underlying acid-induced gastric HCO3(-) secretion.


Asunto(s)
Bicarbonatos/metabolismo , Capsaicina/farmacología , Sulfuro de Hidrógeno/farmacología , Óxido Nítrico/metabolismo , Prostaglandinas/metabolismo , Estómago/efectos de los fármacos , Estómago/fisiología , Animales , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/metabolismo , Indometacina/farmacología , Masculino , NG-Nitroarginina Metil Éster/farmacología , Ratas , Ratas Sprague-Dawley , Células Receptoras Sensoriales/efectos de los fármacos , Células Receptoras Sensoriales/metabolismo , Estómago/inervación , Sulfuros
9.
Digestion ; 91(3): 218-32, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25791157

RESUMEN

BACKGROUND/AIMS: NSAID-induced enteropathy has been the focus of recent basic and clinical research subsequent to the development of the capsule endoscope and double-balloon endoscope. We review the possible pathogenic mechanisms underlying NSAID-induced enteropathy and discuss the role of the inhibition of COX-1/COX-2 and the influences of food as well as various prophylactic treatments on these lesions. METHODS: Studies were performed in experimental animals. RESULTS: Multiple factors, such as intestinal hypermotility, decreased mucus secretion, enterobacteria, and upregulation of iNOS/NO expression, are involved in the pathogenesis of NSAID-induced enteropathy, in addition to the decreased production of PGs due to the inhibition of COX. Enterobacterial invasion is the most important pathogenic event, and intestinal hypermotility, which was associated with this event, is essential for the development of these lesions. NSAIDs also upregulate the expression of COX-2, and the inhibition of both COX-1 and COX-2 is required for the intestinal ulcerogenic properties of NSAIDs to manifest. NSAID-induced enteropathy is prevented by PGE2, atropine, ampicillin, and aminoguanidine as well as soluble dietary fiber, and exacerbated by antisecretory drugs such as proton pump inhibitors. CONCLUSION: These findings on the pathogenesis of NSAID-induced enteropathy will be useful for the future development of intestinal-sparing alternatives to standard NSAIDs.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Enfermedades Intestinales/inducido químicamente , Intestino Delgado/efectos de los fármacos , Animales , Inhibidores de la Ciclooxigenasa/efectos adversos , Fibras de la Dieta/efectos adversos , Fibras de la Dieta/uso terapéutico , Dinoprostona/uso terapéutico , Enterobacteriaceae , Interacciones Alimento-Droga , Motilidad Gastrointestinal/efectos de los fármacos , Enfermedades Intestinales/patología , Enfermedades Intestinales/prevención & control , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Intestino Delgado/microbiología , Intestino Delgado/patología , Ratones , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa/metabolismo , Profilaxis Pre-Exposición/métodos , Prostaglandinas/biosíntesis , Inhibidores de la Bomba de Protones/efectos adversos , Ratas
10.
J Pharmacol Exp Ther ; 348(2): 227-35, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24254524

RESUMEN

Antisecretory drugs such as histamine H2-receptor antagonists and proton pump inhibitors are commonly used for the treatment of upper gastrointestinal mucosal lesions induced by nonsteroidal anti-inflammatory drugs (NSAIDs). However, it has recently been reported that these drugs exacerbate NSAID-induced small intestinal lesions in rats. Unfortunately, there are few effective agents for the treatment of this complication. We examined the effects of mucosal protective agents (MPAs) (misoprostol, irsogladine, and rebamipide) and mucin of porcine stomach on diclofenac-induced intestinal lesions and the exacerbation of the lesions by ranitidine or omeprazole. The effects of the drugs on intestinal motility and mucus distribution/content were also examined. Male Wistar rats (180-220 g) were used. Each drug was administered orally under fed conditions. Diclofenac (1-10 mg/kg) produced multiple lesions in the small intestine dose-dependently. Both ranitidine (30 mg/kg) and omeprazole (100 mg/kg) significantly increased the intestinal lesions induced by low doses (3 and 6 mg/kg) of diclofenac. Misoprostol (0.03-0.3 mg/kg), irsogladine (3-30 mg/kg), and rebamipide (30-300 mg/kg), as well as mucin (30-300 mg/kg) inhibited the formation of intestinal lesions caused by a high dose (10 mg/kg) of diclofenac alone and prevented the exacerbation of diclofenac-induced lesions by antisecretory drugs. Diclofenac (10 mg/kg) markedly increased the intestinal motility and decreased the mucosal mucus, and the decrease of mucus was significantly inhibited by the MPAs. These results indicate the usefulness of the MPAs for the treatment of intestinal lesions induced by NSAIDs alone or by coadministration with antisecretory drugs, and suggest that mucus plays an important role in the protection of intestinal mucosa by the MPAs.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Antiulcerosos/efectos adversos , Fármacos Gastrointestinales/uso terapéutico , Enfermedades Intestinales/prevención & control , Mucosa Intestinal/efectos de los fármacos , Intestino Delgado/efectos de los fármacos , Sustancias Protectoras/uso terapéutico , Alanina/administración & dosificación , Alanina/análogos & derivados , Alanina/uso terapéutico , Animales , Antiulcerosos/uso terapéutico , Diclofenaco/efectos adversos , Relación Dosis-Respuesta a Droga , Mucinas Gástricas/administración & dosificación , Mucinas Gástricas/uso terapéutico , Fármacos Gastrointestinales/administración & dosificación , Enfermedades Intestinales/inducido químicamente , Enfermedades Intestinales/patología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Intestino Delgado/metabolismo , Intestino Delgado/patología , Masculino , Misoprostol/administración & dosificación , Misoprostol/uso terapéutico , Moco/efectos de los fármacos , Moco/metabolismo , Omeprazol/efectos adversos , Omeprazol/uso terapéutico , Sustancias Protectoras/administración & dosificación , Inhibidores de la Bomba de Protones/efectos adversos , Inhibidores de la Bomba de Protones/uso terapéutico , Quinolonas/administración & dosificación , Quinolonas/uso terapéutico , Ranitidina/efectos adversos , Ranitidina/uso terapéutico , Ratas , Ratas Wistar , Sus scrofa , Triazinas/administración & dosificación , Triazinas/uso terapéutico
11.
J Pharmacol Exp Ther ; 349(3): 470-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24713141

RESUMEN

Lubiprostone, a bicyclic fatty acid derived from prostaglandin E1, has been used to treat chronic constipation and irritable bowel syndrome, and its mechanism of action has been attributed to the stimulation of intestinal fluid secretion via the activation of the chloride channel protein 2/cystic fibrosis transmembrane regulator (ClC-2/CFTR) chloride channels. We examined the effects of lubiprostone on indomethacin-induced enteropathy and investigated the functional mechanisms involved, including its relationship with the EP4 receptor subtype. Male Sprague-Dawley rats were administered indomethacin (10 mg/kg p.o.) and killed 24 hours later to examine the hemorrhagic lesions that developed in the small intestine. Lubiprostone (0.01-1 mg/kg) was administered orally twice 30 minutes before and 9 h after the indomethacin treatment. Indomethacin markedly damaged the small intestine, accompanied by intestinal hypermotility, a decrease in mucus and fluid secretion, and an increase in enterobacterial invasion as well as the up-regulation of inducible nitric-oxide synthase (iNOS) and tumor necrosis factor α (TNFα) mRNAs. Lubiprostone significantly reduced the severity of these lesions, with the concomitant suppression of the functional changes. The effects of lubiprostone on the intestinal lesions and functional alterations were significantly abrogated by the coadministration of AE3-208 [4-(4-cyano-2-(2-(4-fluoronaphthalen-1-yl)propionylamino)phenyl)butyric acid], a selective EP4 antagonist, but not by CFTR(inh)-172, a CFTR inhibitor. These results suggest that lubiprostone may prevent indomethacin-induced enteropathy via an EP4 receptor-dependent mechanism. This effect may be functionally associated with the inhibition of intestinal hypermotility and increase in mucus/fluid secretion, resulting in the suppression of bacterial invasion and iNOS/TNFα expression, which are major pathogenic events in enteropathy. The direct activation of CFTR/ClC-2 chloride channels is not likely to have contributed to the protective effects of lubiprostone.


Asunto(s)
Alprostadil/análogos & derivados , Antiinflamatorios no Esteroideos/toxicidad , Antiulcerosos/uso terapéutico , Hemorragia Gastrointestinal/prevención & control , Intestino Delgado/efectos de los fármacos , Subtipo EP4 de Receptores de Prostaglandina E/metabolismo , Alprostadil/administración & dosificación , Alprostadil/uso terapéutico , Animales , Antiulcerosos/administración & dosificación , Regulador de Conductancia de Transmembrana de Fibrosis Quística/antagonistas & inhibidores , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Hemorragia Gastrointestinal/inducido químicamente , Motilidad Gastrointestinal/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Intestino Delgado/inmunología , Intestino Delgado/metabolismo , Intestino Delgado/patología , Lubiprostona , Masculino , Naftalenos/farmacología , Óxido Nítrico Sintasa de Tipo II/biosíntesis , Fenilbutiratos/farmacología , Ratas , Ratas Sprague-Dawley , Subtipo EP4 de Receptores de Prostaglandina E/genética , Factor de Necrosis Tumoral alfa/biosíntesis
12.
J Gastroenterol Hepatol ; 29 Suppl 4: 3-10, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25521725

RESUMEN

BACKGROUND AND AIM: We investigated the roles of cyclooxygenase (COX) isozymes and prostaglandins (PGs) and their receptors in mucosal defense against cold-restraint stress (CRS)-induced gastric lesions. METHODS: Male C57BL/6 wild-type (WT) mice and those lacking COX-1 or COX-2 as well as those lacking EP1, EP3, or IP receptors were used after 18 h fasting. Animals were restrained in Bollman cages and kept in a cold room at 10°C for 90 min. RESULTS: CRS induced multiple hemorrhagic lesions in WT mouse stomachs. The severity of these lesions was significantly worsened by pretreatment with the nonselective COX inhibitors (indomethacin, loxoprofen) or selective COX-1 inhibitor (SC-560), while neither of the selective COX-2 inhibitors (rofecoxib and celecoxib) had any effect. These lesions were also aggravated in animals lacking COX-1, but not COX-2. The expression of COX-2 mRNA was not detected in the stomach after CRS, while COX-1 expression was observed under normal and stressed conditions. The gastric ulcerogenic response to CRS was similar between EP1 or EP3 knockout mice and WT mice, but was markedly worsened in animals lacking IP receptors. Pretreating WT mice with iloprost (the PGI2 analog) significantly prevented CRS-induced gastric lesions in the presence of indomethacin. PGE2 also reduced the severity of these lesions, and the effect was mimicked by the EP4 agonist, AE1-329. CONCLUSIONS: These results suggest that endogenous PGs derived from COX-1 play a crucial role in gastric mucosal defense during CRS, and this action is mainly mediated by PGI2 /IP receptors and partly by PGE2 /EP4 receptors.


Asunto(s)
Frío/efectos adversos , Ciclooxigenasa 1/fisiología , Inhibidores de la Ciclooxigenasa/efectos adversos , Mucosa Gástrica/patología , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/patología , Prostaglandinas I/fisiología , Estrés Fisiológico/fisiología , Animales , Ciclooxigenasa 1/genética , Ciclooxigenasa 1/metabolismo , Dinoprostona/fisiología , Epoprostenol/fisiología , Expresión Génica , Indometacina/efectos adversos , Masculino , Ratones Endogámicos C57BL , Fenilpropionatos/efectos adversos , Pirazoles/efectos adversos , ARN Mensajero/metabolismo , Receptores de Epoprostenol/fisiología , Receptores de Prostaglandina E/fisiología , Subtipo EP4 de Receptores de Prostaglandina E/fisiología
13.
J Gastroenterol Hepatol ; 29 Suppl 4: 37-46, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25521732

RESUMEN

BACKGROUND AND AIM: We examined the prophylactic effect of rebamipide on gastric bleeding induced by the perfusion of aspirin (acetylsalicylic acid [ASA]) plus clopidogrel under the stimulation of acid secretion in rats. METHODS: Under urethane anesthesia, acid secretion was stimulated by the i.v. infusion of histamine (8 mg/kg/h), and the stomach was perfused with 25 mmol/L ASA at a rate of 0.4 mL/min. Gastric bleeding was evaluated as the concentration of hemoglobin in the perfusate. Clopidogrel (30 mg/kg) was given p.o. 24 h before the perfusion. Rebamipide (3-30 mg/kg) or other antiulcer drugs were given i.d. before the ASA perfusion. RESULTS: Slight gastric bleeding or damage was observed with the perfusion of ASA under the stimulation of acid secretion, whereas these responses were significantly increased in the presence of clopidogrel. Both omeprazole and famotidine inhibited acid secretion and prevented these responses to ASA plus clopidogrel. Rebamipide had no effect on acid secretion, but dose-dependently prevented gastric bleeding in response to ASA plus clopidogrel, with the degree of inhibition being almost equivalent to that of the antisecretory drugs, and the same effects were obtained with the gastroprotective drugs, irsogladine and teprenone. These agents also reduced the severity of gastric lesions, although the effects were less than those of the antisecretory drugs. CONCLUSIONS: These results suggest that the antiplatelet drug, clopidogrel, increases gastric bleeding induced by ASA under the stimulation of acid secretion, and the gastroprotective drug, rebamipide, is effective in preventing the gastric bleeding induced under such conditions, similar to antisecretory drugs.


Asunto(s)
Alanina/análogos & derivados , Antiulcerosos/uso terapéutico , Aspirina/administración & dosificación , Aspirina/efectos adversos , Ácido Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Hemorragia Gastrointestinal/inducido químicamente , Hemorragia Gastrointestinal/prevención & control , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/efectos adversos , Quinolonas/uso terapéutico , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/prevención & control , Ticlopidina/análogos & derivados , Alanina/farmacología , Alanina/uso terapéutico , Animales , Antiulcerosos/farmacología , Clopidogrel , Modelos Animales de Enfermedad , Masculino , Quinolonas/farmacología , Ratas Sprague-Dawley , Ticlopidina/administración & dosificación , Ticlopidina/efectos adversos , Resultado del Tratamiento
14.
J Pharmacol Exp Ther ; 344(1): 189-95, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23008503

RESUMEN

Although nonsteroidal anti-inflammatory drugs often cause ulcers in the duodenum in humans, the role of cyclooxygenase (COX) isoforms in the pathogenesis of duodenal ulcers has not been fully elucidated. We examined in cats the 1) ulcerogenic effects of selective COX-1 (SC-560, ketorolac) and COX-2 (celecoxib, meloxicam) inhibitors on the gastrointestinal mucosa, 2) effect of feeding and cimetidine on the expression of COX isoforms and prostaglandin E(2) (PGE(2)) level in the duodenum, and 3) localization of COX isoforms in the duodenum. COX inhibitors were administered after the morning meal in cats once daily for 3 days. Gastrointestinal lesions were examined on day 4. Localization and expression of COX isoforms (by immunohistochemistry, Western blot) and PGE(2) level (by enzyme immunoassay) were examined. Results were as follows. First, selective COX-1 or COX-2 inhibitors alone produced marked ulcers in the duodenum but did not cause obvious lesions in the small intestine. Coadministration of SC-560 and celecoxib produced marked lesions in the small intestine. Second, feeding increased both the expression of COX isoforms and PGE(2) level in the duodenum, and the effects were markedly inhibited by pretreatment with cimetidine. Third, COX-1 was localized in goblet and Brunner's gland cells, Meissner's and Auerbach's plexus, smooth muscle cells, and arterioles; and COX-2 was observed in capillaries, venules, and basal granulated cells. The expression of COX isoforms in the duodenum is up-regulated by feeding, and inhibition of either COX-1 or COX-2 causes ulcers in the duodenum, suggesting that both isoforms play an important role in the protection of the duodenal mucosa.


Asunto(s)
Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/metabolismo , Enfermedades Duodenales/prevención & control , Mucosa Intestinal/patología , Animales , Western Blotting , Gatos , Celecoxib , Cimetidina/farmacología , Inhibidores de la Ciclooxigenasa 2/farmacología , Inhibidores de la Ciclooxigenasa/farmacología , Dieta , Dinoprostona/metabolismo , Enfermedades Duodenales/patología , Duodeno/efectos de los fármacos , Duodeno/metabolismo , Femenino , Antagonistas de los Receptores H2 de la Histamina/farmacología , Inmunohistoquímica , Masculino , Pirazoles/farmacología , Sulfonamidas/farmacología
15.
J Pharmacol Sci ; 121(4): 305-11, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23545479

RESUMEN

Atrophic gastritis caused by infection with Helicobacter pylori is characterized by parietal cell loss, which is a main risk factor for gastric cancer. Parietal cells play a crucial role in the regulation of cell lineage maturation and proliferation in the gastric units. Among the classical cadherins, E-cadherin plays an important role not only in epithelial cell-cell connections, but also in the maintenance of epithelial polarity and gastric glandular architecture and regulation of cell proliferation. The aim of this study is to elucidate how parietal cells and E-cadherin are altered in gastritis with Helicobacter pylori infection. We studied the effects of Helicobacter pylori on gastric mucosal E-cadherin 2 weeks after inoculation and investigated the relationship between parietal cell loss and the amount of E-cadherin on parietal cells in Mongolian gerbils. The number of parietal cells and amount of staining of E-cadherin below the isthmus were investigated by immunohistochemistry. It was shown that a reduction in intercellular E-cadherin preceded the disappearance of parietal cells. The gastric glands where parietal cells were lost were replaced by mucus secreting cells without E-cadherin. These results suggest that Helicobacter pylori damaged E-cadherin on parietal cells and caused massive parietal cell loss, leading to the deregulation of gastric morphology.


Asunto(s)
Cadherinas/fisiología , Gastritis Atrófica/microbiología , Gastritis Atrófica/patología , Infecciones por Helicobacter , Helicobacter pylori , Células Parietales Gástricas/patología , Animales , Cadherinas/metabolismo , Recuento de Células , Proliferación Celular , Mucosa Gástrica/citología , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patología , Gastritis Atrófica/metabolismo , Gerbillinae , Inmunohistoquímica , Masculino , Células Parietales Gástricas/fisiología
16.
Dig Dis Sci ; 58(10): 2840-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23765256

RESUMEN

BACKGROUND/AIMS: The effects of feeding conditions (fasted or fed) and dietary fiber (DF) in the diet on gastrointestinal (GI) damage induced by aspirin (ASA) were examined in cats. METHODS: Plain ASA (P-ASA, 20 mg/kg) or one enteric-coated ASA tablet (EC-ASA, containing 100 mg ASA) was administered p.o. once daily for 3 or 7 days just after morning meal, 3 h after the evening meal, or in the morning without a morning meal (fasted). Several types of diet, dry food (DRY, DF: 2.8 %), canned food (CAN, DF: 0.4 %), and diets with added cellulose or pectin were provided twice daily. RESULTS: P-ASA or EC-ASA administered just after feeding of DRY caused marked lesions in the GI tract, although EC-ASA did not produce any lesions in the stomach. GI damage was markedly decreased when ASA was administered 3 h after the evening meal. The induction of lesions by EC-ASA was markedly decreased in cats that ate CAN, but lesions were induced in cats fed CAN with added cellulose (6 %). The addition of pectin (6 %) to the DRY markedly decreased the induction of lesions by EC-ASA. CONCLUSIONS: The results indicate that the induction of GI lesions by ASA was highly dependent on the feeding conditions and DF. To minimize the induction of GI damage, it would be better to take ASA 3 h after the evening meal, or after consuming diets that contain low amounts of insoluble DF and high amounts of soluble DF.


Asunto(s)
Aspirina/efectos adversos , Dieta , Ingestión de Alimentos/fisiología , Úlcera Péptica/inducido químicamente , Úlcera Péptica/prevención & control , Administración Oral , Animales , Aspirina/administración & dosificación , Aspirina/farmacología , Gatos , Cimetidina/uso terapéutico , Fibras de la Dieta/farmacología , Modelos Animales de Enfermedad , Femenino , Intestinos/efectos de los fármacos , Intestinos/patología , Masculino , Misoprostol/uso terapéutico , Úlcera Péptica/fisiopatología , Estómago/efectos de los fármacos , Estómago/patología , Comprimidos Recubiertos
17.
Gan To Kagaku Ryoho ; 40(11): 1489-95, 2013 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-24231701

RESUMEN

This report summarizes the use of gemcitabine for the treatment of malignant lymphoma. Gemcitabine is a deoxycytidine antagonist that has characteristics different from those of the deoxycytidine antagonist cytarabine(Ara-C). International guidelines based on the results of recent clinical studies recommend the use of gemcitabine as monotherapy and in combination therapy, particularly for relapsed and refractory malignant lymphomas. Clinical studies on gemcitabine monotherapy up to 2012 reported response rates of 51-75% for peripheral T -cell lymphoma and cutaneous T-cell lymphoma. Regarding combination therapy, the GDP regimen consisting of gemcitabine, dexamethasone, and cisplatin was associated with response rates of 62-70% for relapsed or refractory Hodgkin lymphoma and 45-53% for relapsed or refractory non-Hodgkin lymphoma, thereby displaying comparable efficacy to existing salvage chemotherapy regimens. The GDP regimen has a favorable safety profile and is also associated with favorable autologous transplantation rates, which suggests its potential as induction chemotherapy before autologous transplantation. Concerning adverse reactions requiring clinical caution, lung disorder was reported in 8 of 27 patients(30%)who received a regimen of gemcitabine in combination with bleomycin.


Asunto(s)
Antimetabolitos Antineoplásicos/uso terapéutico , Desoxicitidina/análogos & derivados , Linfoma/tratamiento farmacológico , Antimetabolitos Antineoplásicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Citarabina/efectos adversos , Citarabina/uso terapéutico , Desoxicitidina/efectos adversos , Desoxicitidina/uso terapéutico , Humanos , Guías de Práctica Clínica como Asunto , Gemcitabina
18.
Sci Rep ; 13(1): 2644, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36788314

RESUMEN

The aim of this study was to evaluate the influence of skin distortion due to surgical positioning on the clinical accuracy of the navigation system. The distance errors were measured in four fiducial markers (anterior, posterior, right, and left of the head) after the registration of the navigation system. The distance errors were compared between the surface-merge registration (SMR) method using preoperative imaging and the automatic intraoperative registration (AIR) method using intraoperative imaging. The comparison of the distance errors were performed in various surgical positions. The AIR method had the significant accuracy in the lateral markers than the SMR method (lateral position, 3.8 mm vs. 8.95 mm; p < 0.0001; prone position, 4.5 mm vs. 13.9 mm; p = 0.0001; 5.2 mm vs. 11.5 mm; p = 0.0070). The smallest distance errors were obtained close to the surgical field in the AIR method (3.25-3.85 mm) and in the forehead in the SMR method (3.3-8.1 mm). The AIR method was accurate and recommended for all the surgical positions if intraoperative imaging was available. The SMR method was only recommended for the supine position, because skin distortion was frequently observed in the lateral region.


Asunto(s)
Neoplasias Encefálicas , Cirugía Asistida por Computador , Humanos , Cirugía Asistida por Computador/métodos , Posición Prona , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía
19.
Sci Rep ; 13(1): 10173, 2023 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-37349515

RESUMEN

Boron neutron capture therapy (BNCT) is a high-LET particle radiotherapy clinically tested for treating malignant gliomas. Boronophenylalanine (BPA), a boron-containing phenylalanine derivative, is selectively transported into tumor cells by amino acid transporters, making it an ideal agent for BNCT. In this study, we investigated whether the amino acid 5-aminolevulinic acid (ALA) could sensitize glioma stem cells (GSCs) to BNCT by enhancing the uptake of BPA. Using human and mouse GSC lines, pre-incubation with ALA increased the intracellular accumulation of BPA dose-dependent. We also conducted in vivo experiments by intracerebrally implanting HGG13 cells in mice and administering ALA orally 24 h before BPA administration (ALA + BPA-BNCT). The ALA preloading group increased the tumor boron concentration and improved the tumor/blood boron concentration ratio, resulting in improved survival compared to the BPA-BNCT group. Furthermore, we found that the expression of amino acid transporters was upregulated following ALA treatment both in vitro and in vivo, particularly for ATB0,+. This suggests that ALA may sensitize GSCs to BNCT by upregulating the expression of amino acid transporters, thereby enhancing the uptake of BPA and improving the effectiveness of BNCT. These findings have important implications for strategies to improve the sensitivity of malignant gliomas to BPA-BNCT.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Neoplasias Encefálicas , Glioma , Humanos , Animales , Ratones , Ácido Aminolevulínico/farmacología , Boro , Glioma/radioterapia , Células Madre Neoplásicas , Compuestos de Boro , Neoplasias Encefálicas/radioterapia
20.
Neuroimage ; 59(2): 1735-44, 2012 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-21867764

RESUMEN

A number of behavioral studies suggest that infant-directed speech (IDS) plays a more important role in facilitating both: a) speech perception, and b) adult-infant social interactions than does adult-directed speech (ADS), and hence that IDS contributes to subsequent social and language development. However neural substrates that may underlie these IDS functions have not been examined. The present study examined cerebral hemodynamic responses to IDS in 48 infants (4-13 months of age) using near-infrared spectroscopy (NIRS). Japanese sentences uttered by the infants' own mothers and by unfamiliar mothers were used to record activations in temporal and frontal area separately. Increased activations were observed predominantly in infants' left and right temporal areas when they listened to IDS rather than to ADS when both involved voices of their own and unfamiliar mothers. In contrast, significantly greater activations were observed in the frontal area when infants listened to IDS produced by their own mothers, not when IDS arose from unfamiliar mothers. Furthermore, the present results indicate that responses to IDS do vary as a function of the infant's age and the talker familiarity. These findings suggest a differential function for frontal and temporal areas in processing infant-directed speech by the different speakers.


Asunto(s)
Lóbulo Frontal/fisiología , Desarrollo del Lenguaje , Relaciones Madre-Hijo , Madres , Percepción del Habla/fisiología , Lóbulo Temporal/fisiología , Mapeo Encefálico , Femenino , Humanos , Lactante , Masculino
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