RESUMEN
BACKGROUND AND PURPOSE: Chemotherapeutic agents, including 5-fluorouracil (5-FU), frequently cause intestinal mucositis resulting in severe diarrhoea and morphological mucosal damage. 5-HT3 receptor antagonists are clinically effective in the treatment of nausea and emesis during cancer chemotherapy. Therefore we here have examined the effects of 5-HT3 receptor antagonists on 5-FU-induced intestinal mucositis in mice. EXPERIMENTAL APPROACH: Intestinal mucositis was induced in male C57BL/6 mice by daily administration of 5-FU (50 mg·kg⻹) for 5 days. Effects of 5-HT3 receptor antagonists, ramosetron (0.01-0.1 mg·kg⻹) and ondansetron (5 mg·kg⻹), on the accompanying histology, cytokine production and apoptosis were assessed. KEY RESULTS: Continuous administration of 5-FU to mice caused severe intestinal mucositis, which was histologically characterized by the shortening of villi and destruction of intestinal crypts, accompanied by body weight loss and diarrhoea. Daily ramosetron administration dose-dependently reduced the severity of intestinal mucositis, body weight loss and diarrhoea. Similar beneficial effects were observed with ondansetron. The number of apoptotic, caspase-3- and caspase-8-activated cells increased 24 h after the first 5-FU administration, and these responses were reduced by ramosetron. The up-regulation of TNF-α, IL-1ß and IL-6 following 5-FU treatment was also attenuated by ramosetron. CONCLUSIONS AND IMPLICATIONS: 5-HT3 receptor antagonists ameliorated 5-FU-induced intestinal mucositis in mice, and this action could result from suppression of apoptotic responses in the intestinal crypt cells via inhibition of cytokine expression. Thus, 5-HT3 receptor antagonists may be useful for preventing not only nausea and emesis but also intestinal mucositis during 5-FU chemotherapy.
Asunto(s)
Antimetabolitos Antineoplásicos/efectos adversos , Apoptosis/efectos de los fármacos , Fluorouracilo/efectos adversos , Inmunosupresores/efectos adversos , Mucosa Intestinal/efectos de los fármacos , Mucositis/prevención & control , Antagonistas del Receptor de Serotonina 5-HT3/uso terapéutico , Animales , Antimetabolitos Antineoplásicos/uso terapéutico , Proteínas Reguladoras de la Apoptosis/antagonistas & inhibidores , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Bencimidazoles/administración & dosificación , Bencimidazoles/efectos adversos , Bencimidazoles/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Citocinas/genética , Citocinas/metabolismo , Diarrea/etiología , Diarrea/prevención & control , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Fluorouracilo/antagonistas & inhibidores , Fluorouracilo/uso terapéutico , Fármacos Gastrointestinales/administración & dosificación , Fármacos Gastrointestinales/uso terapéutico , Regulación de la Expresión Génica/efectos de los fármacos , Inmunosupresores/antagonistas & inhibidores , Inmunosupresores/uso terapéutico , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Mucositis/inducido químicamente , Mucositis/metabolismo , Mucositis/patología , Ondansetrón/efectos adversos , Ondansetrón/uso terapéutico , Agonistas del Receptor de Serotonina 5-HT3/efectos adversos , Agonistas del Receptor de Serotonina 5-HT3/uso terapéutico , Antagonistas del Receptor de Serotonina 5-HT3/administración & dosificación , Antagonistas del Receptor de Serotonina 5-HT3/efectos adversosRESUMEN
We have recently found that the combination of ovariectomy (OVX) and chronic restraint stress (CS) causes hippocampal pyramidal cell loss and cognitive dysfunction in female rats and that estrogen replacement prevents the OVX/CS-induced morphological and behavioral changes. In this study, to clarify the mechanisms underlying the OVX/CS-mediated memory impairment further, we examined the roles of cholinergic systems in the OVX/CS-induced memory impairment in mice. Female Slc:ICR strain mice were randomly divided into two groups: OVX and sham-operated groups. Two weeks after the operation, the mice of each group were further assigned to CS (6 h/day) or non-stress group. Following the 3-week-stress period, all mice were subjected to contextual fear conditioning, and context- and tone-dependent memory tests were conducted 1 or 24 h after the conditioning. Overburden with 3 weeks of CS from 2 weeks after OVX impaired context- and tone-dependent freezing and the OVX/CS caused significant Nissl-stained neuron-like cell loss in the hippocampal CA3 region, although OVX and CS alone did not cause such behavioral and histological changes. Replacement of 17ß-estradiol for 5 weeks after OVX suppressed OVX/CS-induced memory impairment and hippocampal Nissl-positive cell loss. Furthermore, the OVX/CS mice exhibited a significant decrease in choline acetyltransferase in the hippocampus compared with other groups. The cholinesterase inhibitors donepezil and galantamine ameliorated OVX/CS-induced memory impairment. These data suggest that cholinergic dysfunction may be involved in the OVX/CS-induced conditioned fear memory impairment. Overall, our findings suggest that the OVX/CS mouse model is useful to study the mechanisms underlying estrogen loss-induced memory deficits.
Asunto(s)
Reacción de Prevención/fisiología , Hipocampo/fisiopatología , Trastornos de la Memoria/fisiopatología , Degeneración Nerviosa/fisiopatología , Estrés Psicológico/fisiopatología , Animales , Neuronas Colinérgicas/metabolismo , Neuronas Colinérgicas/patología , Enfermedad Crónica , Modelos Animales de Enfermedad , Femenino , Hormonas Esteroides Gonadales/deficiencia , Hipocampo/patología , Trastornos de la Memoria/etiología , Trastornos de la Memoria/patología , Ratones , Ratones Endogámicos ICR , Degeneración Nerviosa/etiología , Degeneración Nerviosa/patología , Ovariectomía/efectos adversos , Estrés Psicológico/complicaciones , Estrés Psicológico/patologíaRESUMEN
Advanced glycation end products (AGEs) and their receptor (RAGE) have been shown to play a role in insulin resistance. We have previously shown that combination therapy with nateglinide (NAT) and telmisartan (TEL) improves postprandial metabolic derangements in Zucker fatty (ZF) rats, an animal model of insulin resistance with obesity. However, effects of combination therapy on insulin resistance remain unknown. We investigated here whether combination therapy with TEL and NAT could ameliorate insulin resistance in ZF rats by suppressing AGE-RAGE axis. NAT and/or TEL inhibited insulin receptor substrate-1 (IRS-1) serine phosphorylations at 307 and 636/639 residues in the liver of ZF rats. Further, combination therapy with NAT and TEL, but not each monotherapy alone, significantly restored the decrease in hepatic IRS-1 tyrosine phosphorylation in these animals. In addition, serum levels of AGEs, RAGE expression levels in the liver and hepatic AGE-RAGE index were decreased in NAT plus TEL-treated ZF rats. The present study suggests that combination therapy with NAT and TEL could ameliorate insulin resistance in ZF rats by suppressing the AGE-RAGE axis in the liver.
Asunto(s)
Bencimidazoles/administración & dosificación , Benzoatos/administración & dosificación , Ciclohexanos/administración & dosificación , Regulación hacia Abajo , Resistencia a la Insulina , Fenilalanina/análogos & derivados , Receptores Inmunológicos/metabolismo , Animales , Modelos Animales de Enfermedad , Quimioterapia Combinada , Productos Finales de Glicación Avanzada/metabolismo , Humanos , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Nateglinida , Fenilalanina/administración & dosificación , Ratas , Ratas Zucker , Receptor para Productos Finales de Glicación Avanzada , TelmisartánRESUMEN
As typical periodontopathic bacteria, Porphyromonas gingivalis (P. gingivalis) and Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) were exposed to electrolyzed ion-reduced water (ERI) and ERI containing 1% sodium carboxymethylcellulose (CMC-Na) (ERI-1% CMC-Na), and the time course of their bactericidal action was evaluated. More than 99% of each bacteria species were killed after exposure to each solution for 15 sec. In addition, 1% CMC-Na, which was added to prolong bactericidal action, did not affect the bactericidal action of ERI. Its bactericidal action was concentration-dependent. No viable P. gingivalis bacteria were observed at a concentration of 15% of the undiluted solution and no viable A. actinomycetemcomitans bacteria were observed at a concentration of 50%, indicating differences in the bactericidal action of ERI for the two bacteria species. These results suggest that ERI may be extremely useful in preventing and treating periodontal diseases.
RESUMEN
Postprandial metabolic derangements are one of the risk factors of cardiovascular disease in humans. Insulin resistance and/or impaired early-phase insulin secretion are major determinants of postprandial metabolic derangements. In this study, we investigated the potential utility of combination therapy with vildagliptin, a dipeptidyl peptidase IV (DPP-IV) inhibitor and nateglinide, a rapid-onset/short-duration insulinotropic agent, for the treatment of postprandial metabolic derangements in Zucker Fatty (ZF) rats, an animal model of obesity with insulin resistance. ZF rats fed twice daily with or without high fat diet (HFD) were given vehicle, 50 mg/kg of nateglinide, 10 mg/kg of vildagliptin, or both for 6 weeks. Combination therapy with nateglinide and vildagliptin for 2 weeks ameliorated postprandial hyperglycemia, hypertriglyceridemia, and elevation of free fatty acid in ZF rats fed with HFD. 6-week treatment with nateglinide and vildagliptin not only increased hepatic levels of phosphorylated forkhead box protein 1A (FOXO1A), but also reduced triglyceride contents in the liver. Combination therapy also prevented the loss of pancreatic islet mass in ZF rats fed with HFD. These observations demonstrate that combination therapy with nateglinide and vildagliptin may improve postprandial metabolic derangements probably by ameliorating early phase of insulin secretion and hepatic insulin resistance, respectively, in ZF rats fed with HFD. Since combination therapy with nateglinide and vildagliptin restored the decrease in pancreatic beta cell mass, our present findings suggest that combination therapy could be a promising therapeutic strategy for postprandial dysmetabolism associated with obese and insulin resistance.
Asunto(s)
Adamantano/análogos & derivados , Ciclohexanos/uso terapéutico , Hipoglucemiantes/uso terapéutico , Enfermedades Metabólicas/tratamiento farmacológico , Enfermedades Metabólicas/fisiopatología , Nitrilos/uso terapéutico , Fenilalanina/análogos & derivados , Periodo Posprandial/fisiología , Pirrolidinas/uso terapéutico , Adamantano/farmacología , Adamantano/uso terapéutico , Animales , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Ciclohexanos/farmacología , Quimioterapia Combinada , Ácidos Grasos/sangre , Factores de Transcripción Forkhead/metabolismo , Hipoglucemiantes/farmacología , Insulina/sangre , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patología , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Enfermedades Metabólicas/sangre , Nateglinida , Proteínas del Tejido Nervioso , Nitrilos/farmacología , Tamaño de los Órganos/efectos de los fármacos , Fenilalanina/farmacología , Fenilalanina/uso terapéutico , Fosforilación/efectos de los fármacos , Periodo Posprandial/efectos de los fármacos , Pirrolidinas/farmacología , Ratas , Ratas Zucker , Triglicéridos/sangre , VildagliptinaRESUMEN
There is a growing body of evidence that postprandial hyperglycaemia plays an important role in accelerated atherosclerosis and may be a therapeutic target for preventing cardiovascular disease (CVD) in diabetes. However, there is no convenient biomarker that could reflect cumulative postprandial hyperglycaemia in diabetes. We have recently found that glyceraldehyde can rapidly react with amino groups of proteins to form glyceraldehyde-derived advanced glycation end products (AGEs), which evoke vascular inflammation and endothelial dysfunction, thereby being implicated in accelerated atherosclerosis in diabetes. In this study, we examined whether glyceraldehyde-derived AGEs were a biomarker that could reflect cumulative postprandial hyperglycaemia in Goto-Kakizaki (GK) rats fed twice a day. GK rats at 8 weeks of age were divided into 2 groups; either the vehicle (VEH) or 50 mg/kg of nateglinide (NAT) was administered twice daily just before each meal. After 6 weeks, nateglinide treatment was found to not only prevent postprandial hyperglycaemia, but also reduce glyceraldehyde-derived AGE levels in GK rats fed twice a day. However, there was no significant difference in HbA1c or glucose-derived AGE levels between the two groups. The present study demonstrated for the first time that glyceraldehyde-derived AGEs, but not HbA1c or glucose-derived AGEs, were a biomarker that could reflect cumulative postprandial hyperglycaemia in diabetic rats. Glyceraldehyde-derived AGEs may be a novel therapeutic target for preventing CVD in diabetes.
Asunto(s)
Biomarcadores/metabolismo , Diabetes Mellitus Experimental/metabolismo , Productos Finales de Glicación Avanzada/metabolismo , Gliceraldehído/metabolismo , Hiperglucemia/metabolismo , Periodo Posprandial , Animales , Masculino , Estrés Oxidativo , RatasRESUMEN
The metabolic syndrome is strongly associated with insulin resistance and has been recognized as a cluster of risk factors for cardiovascular disease. Insulin resistance and/or impaired early-phase insulin secretion are major determinants of postprandial hyperglycemia. In this study, we investigated the potential utility of combination therapy with telmisartan, an angiotensin II receptor blocker and nateglinide, a rapid-onset/short-duration insulinotropic agent, for the treatment of postprandial hyperglycemia and metabolic derangements in Zucker Fatty (ZF) rats. ZF rats fed twice daily were given vehicle, 50 mg/kg of nateglinide, 5 mg/kg of telmisartan, or both for 6 weeks. Combination therapy with nateglinide and telmisartan for 2 weeks ameliorated postprandial hyperglycemia in ZF rats fed twice daily. Furthermore, 6-week treatment with nateglinide and telmisartan not only decreased fasting plasma insulin, triglycerides, and free fatty acid levels, but also improved the responses of blood glucose to insulin and subsequently reduced the decremental glucose areas under the curve in the ZF rats. Combination therapy also restored the decrease of plasma adiponectin levels in the ZF rats. Monotherapy with nateglinide or telmisartan alone didnot significantly improve these metabolic parameters. These observations demonstrate that combination therapy with nateglinide and telmisartan may improve the metabolic derangements by ameliorating early phase of insulin secretion as well as insulin resistance in ZF rats fed twice daily. Our present findings suggest that the combination therapy with nateglinide and telmisartan could be a promising therapeutic strategy for the treatment of the metabolic syndrome.
Asunto(s)
Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Bencimidazoles/uso terapéutico , Benzoatos/uso terapéutico , Ciclohexanos/uso terapéutico , Hipoglucemiantes/uso terapéutico , Enfermedades Metabólicas/tratamiento farmacológico , Fenilalanina/análogos & derivados , Adiponectina/sangre , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Animales , Bencimidazoles/farmacología , Benzoatos/farmacología , Glucemia/efectos de los fármacos , Presión Sanguínea/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Ciclohexanos/farmacología , Quimioterapia Combinada , Hemoglobina Glucada/metabolismo , Hipoglucemiantes/farmacología , Insulina/sangre , Insulina/farmacología , Lípidos/sangre , Masculino , Nateglinida , Fenilalanina/farmacología , Fenilalanina/uso terapéutico , Ratas , Ratas Zucker , TelmisartánRESUMEN
We have recently found that a combination of ovariectomy (OVX) and chronic restraint stress causes cognitive dysfunction and reduces hippocampal CA3 neurons in female rats and that estrogen replacement suppresses the OVX/stress-induced behavioral and morphological changes. In this study, we examined the effect of Ginkgo biloba extract (EGb 761), a popular herbal supplement, on the cognitive dysfunction and neuromorphological change in OVX/stress-subjected rats. Female Fisher 344 rats were randomly divided into three groups: vehicle-treated OVX, EGb 761 (50 mg/kg) -treated OVX and vehicle-treated sham-operated control groups. Two months after ovariectomy, all animals received restraint stress for 21 days (6 h/day), and were then subjected to a novel object recognition test followed by morphological examination by Nissl staining. EGb 761 was orally administered once daily until the behavioral analysis was done. Treatment with EGb 761 improved memory impairment and neuronal loss of hippocampus in the OVX/stress-subjected group in the same ways as 17beta-estradiol. On the other hand, EGb 761 did not affect the loss of bone mineral density and increase in body weight after OVX, although 17beta-estradiol attenuated them. These results have important implications for neuroprotective and cognition enhancing effects of EGb 761 in postmenopausal women and suggest that the effects are mediated by a different mechanism from estrogen.
Asunto(s)
Trastornos del Conocimiento/tratamiento farmacológico , Ginkgo biloba/química , Hipocampo/patología , Neuronas/patología , Extractos Vegetales/farmacología , Estrés Psicológico/tratamiento farmacológico , Animales , Densidad Ósea/efectos de los fármacos , Recuento de Células , Enfermedad Crónica , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/psicología , Femenino , Tamaño de los Órganos/efectos de los fármacos , Ovariectomía , Desempeño Psicomotor/efectos de los fármacos , Desempeño Psicomotor/fisiología , Ratas , Ratas Endogámicas F344 , Reconocimiento en Psicología/efectos de los fármacos , Restricción Física , Estrés Psicológico/patología , Estrés Psicológico/psicología , Útero/efectos de los fármacos , Aumento de Peso/efectos de los fármacosRESUMEN
The mechanism of gastrointestinal dysmotility in inflammatory bowel disease has not been clarified. In this study, we examined the mechanism involved in the inflamed distal colon isolated from a mouse model of dextran sodium sulphate-induced ulcerative colitis (DSS-treated mouse). Although substance P-induced contraction was not changed, carbachol-induced contraction was reduced in the DSS-treated mouse colon. Pre-incubation with the NO synthase inhibitor N(G)-monomethyl-L-arginine (L-NMMA) or the cyclooxygenase inhibitor indomethacin did not reverse the carbachol-induced contraction in the DSS-treated mouse colon. In semi-quantitative reverse transcription-polymerase chain reaction experiments and Western blot analysis, muscarinic M3 receptor expressions were not changed. The Ca2+ -sensitization of contractile elements induced by carbachol with GTP or GTPgammaS was reduced in the beta-escin-permeabilized DSS-treated mouse colon. Although the expression of proteins such as rhoA, ROCK1, ROCK2 or MYPT1 in smooth muscles was not changed, the expression of CPI-17, the functional protein involved in smooth muscle Ca2+ -sensitization, was significantly decreased in the DSS-treated mouse colon. These results suggest that the suppression of carbachol-induced contraction in mice with colitis is attributable at least partially to the increased activity of myosin phosphatase following the downregulation of CPI-17.
Asunto(s)
Colitis/metabolismo , Motilidad Gastrointestinal/fisiología , Proteínas Musculares/metabolismo , Músculo Liso/metabolismo , Fosfoproteínas/metabolismo , Animales , Anticoagulantes/toxicidad , Western Blotting , Carbacol/farmacología , Agonistas Colinérgicos/farmacología , Colitis/inducido químicamente , Colitis/patología , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Regulación hacia Abajo , Inhibidores Enzimáticos/farmacología , Femenino , Motilidad Gastrointestinal/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular , Ratones , Ratones Endogámicos BALB C , Contracción Muscular/efectos de los fármacos , Contracción Muscular/fisiología , Proteínas Musculares/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Fosfoproteínas/efectos de los fármacos , Receptor Muscarínico M3/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
OBJECTIVE: Amelogenesis imperfecta (AI) is a heterogeneous group of genetic disorders characterized by developmental abnormalities of tooth enamel. The AI is also seen as part of multi-organ abnormalities, e.g. with cone-rod dystrophy, hypothalamo-hypophyseal insufficiency and renal failure. The present patient with AI and nephrocalcinosis exhibited a phenotype different from previous cases with renal failure. To highlight the characteristics of this rare case, extensive analysis that included histological, biochemical and genetic examinations was performed. PATIENT: The present Japanese male patient exhibited dentition with AI and bilateral cleft lip and palate. Ground sections of his extracted tooth showed that it was hypomaturation-type AI, unlike previous cases with nephrocalcinosis were hypoplastic-type. He showed nephrocalcinosis and hematuria at 15 years of age but these symptoms appeared to be secondary to polycystic kidney disease. He showed skeletal Class II pattern with a retrognathic profile and retroclined incisors of both arches. A dolicofacial appearance was seen with an enlarged gonial angle. Biochemical makers including serum alkaline phosphatase, parathyroid hormone, calcitonin, calcium, and phosphate, were all in the normal range. Sequence analysis of the genes encoding amelogenin and enamelin, which are known to be responsible for hypoplastic-type AI, did not reveal any mutations. Since mouse null mutant of homeobox transcription factor, Msx2, exhibits a phenotype resembling AI, the human homolog of this gene, MSX2, was sequenced. There was a missense mutation of T447C that resulted in the conversion of methionine to threonine at 129.
Asunto(s)
Amelogénesis Imperfecta/patología , Labio Leporino/patología , Fisura del Paladar/patología , Enfermedades Renales Poliquísticas/patología , Adulto , Fosfatasa Alcalina/sangre , Amelogenina , Calcitonina/sangre , Calcio/sangre , Citosina , Proteínas de Unión al ADN/genética , Proteínas del Esmalte Dental/genética , Hematuria/patología , Proteínas de Homeodominio/genética , Humanos , Masculino , Maloclusión Clase II de Angle/patología , Metionina/genética , Mutación Missense/genética , Nefrocalcinosis/patología , Hormona Paratiroidea/sangre , Fosfatos/sangre , Retrognatismo/patología , Treonina/genética , TiminaRESUMEN
Our previous study showed that tooth germs at late embryonic stage [later than embryonic day 17.5 (E17.5)] and neonatal homozygous parathyroid hormone-related protein (PTHrP)-knockout mice are compressed or penetrated by the surrounding alveolar bone tissue. In vivo and in vitro studies have shown that the development of the tooth germ proper is not disturbed, but insufficient alveolar bone resorption, due to the decreased number and hypofunction of osteoclasts, is the main cause of this abnormality. In addition to the insufficient alveolar bone resorption, progressive bone formation toward tooth germs was observed in homozygous mice, suggesting that accelerated bone formation also contributes to this abnormality. To further investigate this, homozygous mice at E14.0 and E15.5, when alveolar bone is forming, were used for histochemical and bone histomorphometric analyses. In contrast to the late embryonic stage, the alveolar bone did not yet compress developing tooth germs in homozygous mice on E14.0, but a larger amount of bone tissue was seen compared to wild-type littermates. Histomorphometric analysis of bone at E14.0 revealed that the osteoblast numbers and surfaces in the mandibles and in the bone collar of femora of homozygous mice were significantly higher than those of wild-type mice. However, unlike our previous study showing the osteoclast surface on E18.5 in homozygous mice to be significantly lower than that of wild-type mice, this study at E14.0 showed no significant difference between the two genotypes. To evaluate the amount of calcification around tooth germs, 3D images of mandibles were reconstructed from the calcein-labeled sections of the wild-type and mutant mice. Labeling was performed at E14.0, and the mice were sacrificed 1 h after the calcein injection to minimize the effect of bone resorption. Comparison of the 3D images revealed that the labeled surface was larger around developing tooth germs in homozygous mouse than in wild-type mouse. On day E15.5, osteoblasts approached the enamel organ of homozygous mice but this was not observed in wild-type mice. In this study, we report a systemic increase in osteoblast number and accelerated bone formation in homozygous PTHrP-knockout mice, both of which contribute to the abnormal tooth development.
Asunto(s)
Osteoblastos/patología , Osteogénesis/genética , Proteína Relacionada con la Hormona Paratiroidea/genética , Germen Dentario/patología , Fosfatasa Ácida/metabolismo , Fosfatasa Alcalina/metabolismo , Animales , Calcinosis/enzimología , Calcinosis/metabolismo , Calcinosis/patología , Condrocitos/patología , Fémur/química , Fémur/enzimología , Fémur/patología , Histocitoquímica , Isoenzimas/metabolismo , Mandíbula/química , Mandíbula/enzimología , Mandíbula/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Osteoblastos/química , Osteoblastos/enzimología , Osteoclastos/enzimología , Proteína Relacionada con la Hormona Paratiroidea/metabolismo , Fosfatasa Ácida Tartratorresistente , Germen Dentario/química , Germen Dentario/embriologíaRESUMEN
AIM: The aim of this study was to clarify the role of an early insulin secretion in postprandial hyperglycaemia and hyperlipidaemia; a study using spontaneously type 2 diabetic Otsuka Long-Evans Tokushima Fatty rats with visceral obesity was performed to investigate the acute effect of nateglinide (NAT) vs. glibenclamide (GB) on increases in glucose after glucose loading and on increases in triglyceride (TG) after fat loading. METHODS: Fasting rats were given 50 mg/kg of NAT, 1 mg/kg of GB or 5% methyl cellulose (vehicle) as control and then immediately given oral glucose 1 g/kg. RESULTS: An acute increase in insulin levels in portal blood peaked at 15 min in the NAT group, while insulin levels in the GB group continued to increase significantly after 60 min. Glucose levels in peripheral blood were significantly lower in the NAT group at 30 and 60 min and in the GB group at 120, 180 and 270 min after glucose loading, compared with those in the vehicle group. Subsequently, fasting rats were given NAT, GB or vehicle and then immediately given oral fat emulsion (soy oil 2 g/kg). An acute increase in insulin secretion was seen with NAT, peaking at 30 min, while TG, chylomicron and very low-density lipoprotein levels after fat loading were shown to be significantly lower with NAT than with vehicle. However, the continued insulin secretion observed with GB led to no significant decrease in TG levels after fat loading. In addition, lipoprotein lipase mRNA expression in adipose tissue increased significantly 120 min after NAT administration in comparison with baseline. This increase was not noted with GB administration. CONCLUSION: Abnormalities in early insulin secretion are closely associated with the pathogenesis of various disease conditions that combine to characterize type 2 diabetes, suggesting that normalizing early insulin response in portal blood represents an important treatment not only for postprandial hyperglycaemia but also for postprandial hyperlipidaemia.
Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Hiperglucemia/sangre , Hiperlipidemias/sangre , Hipoglucemiantes/farmacología , Insulina/metabolismo , Fenilalanina/análogos & derivados , Tejido Adiposo/metabolismo , Animales , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Ciclohexanos/farmacología , Grasas de la Dieta/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Gliburida/farmacología , Insulina/sangre , Secreción de Insulina , Lipoproteína Lipasa/biosíntesis , Lipoproteína Lipasa/genética , Masculino , Nateglinida , Fenilalanina/farmacología , Periodo Posprandial , ARN Mensajero/genética , Ratas , Ratas Endogámicas OLETF , Ratas Long-Evans , Triglicéridos/sangreRESUMEN
Clarithromycin (CAM) and rifampicin (RFP) have both been recognized to be effective antibiotic agents against Mycobacterium avium complex (MAC) infection. Rifamycin derivatives including RFP and rifabutin modulate the CAM metabolism by inducing the hepatic cytochrome p-450 3A4. To clarify the effect of RFP on the CAM metabolism, we measured the plasma concentration of CAM and 14-R-hydroxyclarithromycin (M-5), the major metabolite of CAM, in 9 patients suffering from MAC infection before and after the addition of RFP. After the addition of RFP, the mean plasma concentration of CAM significantly decreased, while that of M-5 did not. In addition, the amount of CAM + M-5 concentration also significantly decreased. As M-5 is less effective against MAC infection than CAM, more attention should thus be paid to the plasma CAM concentration in patients administered CAM and RFP concomitantly.
Asunto(s)
Antibacterianos/sangre , Antibióticos Antituberculosos/farmacología , Claritromicina/sangre , Interacciones Farmacológicas , Infección por Mycobacterium avium-intracellulare/tratamiento farmacológico , Infección por Mycobacterium avium-intracellulare/metabolismo , Rifampin/farmacología , Anciano , Anciano de 80 o más Años , Antibacterianos/administración & dosificación , Antibióticos Antituberculosos/administración & dosificación , Claritromicina/administración & dosificación , Claritromicina/análogos & derivados , Citocromo P-450 CYP3A , Sistema Enzimático del Citocromo P-450/metabolismo , Quimioterapia Combinada , Femenino , Humanos , Hígado/enzimología , Masculino , Persona de Mediana Edad , Rifampin/administración & dosificación , Factores de TiempoRESUMEN
Osteoclasts are multinucleated cells with the specialized function of resorbing calcified tissues. These cells develop from hemopoietic cells of the monocyte-macrophage lineage with the support of osteoblasts/stromal cells. Tooth eruption is a vertical movement of teeth via creation of an eruption pathway in and through the alveolar bone. The precise cellular and molecular determinants of tooth eruption are not yet clear, and a cell culture system that can reproduce the activity of osteoclast formation during tooth eruption is expected to be a useful tool to clarify the mechanism of eruption pathway formation. To this end, mandibular bodies, including incisors and molars, were isolated from 9- to 11-day-old mice undergoing active tooth eruption. Primary cells were obtained from mandibular bodies by enzymatic digestion and cultured in alphaMEM containing 15% FBS without any cytokine or growth factor or hormone in the culture (AFT culture, for alveolar bone, dental follicle, and tooth). A progressive increase in the number of tartrate-resistant acid phosphatase-positive multinucleated osteoclastic cells was observed in AFT culture. The osteoclastic cells generated were immunopositive for cathepsin K and calcitonin receptor, and formed resorption pits when cultured on dentine slices. Parathyroid hormone-related protein (PTHrP), expressed by the enamel organ of tooth, is reported to be an essential factor in creation of the eruption pathway. To verify this point, cells were isolated from mandibular bodies from which all teeth and dental follicles had been removed and cultured similarly (A culture, for alveolar bone). Osteoclastic cells were not formed and PTHrP production was hardly detected in the medium of A culture, in contrast to the high level of PTHrP in AFT culture. Since our previous study demonstrated that neonatal homozygous PTHrP-knockout mice show impaired osteoclastogenesis around tooth germs, AFT culture was performed by using this sample to examine whether this culture system can reproduce the status of osteoclastogenesis observed in vivo. The result showed that none of the osteoclastic cells were generated from cells of homozygous mice. We here report a novel mouse osteoclast culture system that reproduces the activity of osteoclast formation around erupting teeth without addition of any cytokine or growth factor or hormone to the medium. Histological examination of various transgenic and mutant mice now offers valuable findings on studies of tooth eruption and the present culture system using these animals would be a powerful tool in clarifying the cellular and molecular mechanisms of eruption pathway formation.
Asunto(s)
Técnicas de Cultivo de Célula/métodos , Incisivo/citología , Diente Molar/citología , Osteoclastos/citología , Animales , Humanos , Incisivo/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Diente Molar/metabolismo , Osteoclastos/metabolismo , Proteína Relacionada con la Hormona Paratiroidea/deficiencia , Proteína Relacionada con la Hormona Paratiroidea/genética , Ratas , Ratas Sprague-Dawley , Diente no Erupcionado/anatomía & histología , Diente no Erupcionado/metabolismoRESUMEN
Parathyroid hormone-related protein (PTHrP) is involved in epithelial-mesenchymal cell interactions during development of various tissues and organs. Tooth germ development is a classical model for this interaction. In tooth germs, PTHrP is expressed in the enamel organ (epithelial component), whereas its major receptor, the type I PTH/PTHrP receptor is expressed in cells of the alveolar bone and dental follicle (mesenchymal components). To clarify the role of PTHrP during fetal tooth germ development, PTHrP gene-knockout mice were used for histochemical and ultrastructural analysis. In wild-type mice, osteoclastic cells were aligned predominantly in the inner aspects of the alveolar bone surrounding the developing tooth germs throughout the late embryonic (after embryonic, 17.5 days) and neonatal animals examined. In contrast, osteoblasts were predominant in corresponding areas of fetal homozygous PTHrP-gene knockout mice with only occasional osteoclasts. In such areas, cell-free surfaces showing cement line-like tartrate-resistant acid phosphatase (TRAP) reactions were frequently observed. In neonatal homozygous mice, bone spicules were often shown to penetrate and/or compress the enamel organ and caused partial destruction of the tooth germs. Osteoclasts were few in number in the inner aspects of the alveolar bone, and had poorly developed ruffled border. No morphological abnormality was noted in cells of the tooth germs proper. On bone surfaces away from developing tooth germs, functional osteoclasts with structural features similar to those in wild-type mice were observed in homozygous mice. These observations suggest that PTHrP is required to maintain an appropriate spatiotemporal arrangement of bone cells and osteoclast function, which are necessary for the normal development of tooth germ and alveolar bone encasing the tooth germ. The observation also demonstrates that PTHrP deficiency affects the structure and function of osteoclasts exclusively those located in the vicinity of the growing tooth germ.
Asunto(s)
Odontogénesis/genética , Odontogénesis/fisiología , Proteínas/genética , Proteínas/fisiología , Diente/crecimiento & desarrollo , Fosfatasa Ácida/metabolismo , Animales , Animales Recién Nacidos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía Electrónica , Modelos Biológicos , Osteoclastos/citología , Osteoclastos/fisiología , Proteína Relacionada con la Hormona Paratiroidea , Germen Dentario/citología , Germen Dentario/embriología , Germen Dentario/crecimiento & desarrolloRESUMEN
Studies were made on the physically disabled and scoliotic children who underwent tracheostomy. The purpose was to clarify factors that might lead to the tracheo-innominate artery fistula, by use of three-dimensional helical CT (3 DCT). In a case of right scoliosis, the tracheo-innominate artery fistula may be caused by the left-ward displacement of the trachea from the vertebra, having the innominate artery ride over the trachea and compressing it. In a case of the physically disabled and scoliotic children, there may be more compression on the trachea by the innominate artery along with the worsening scoliosis. Therefore, we consider it necessary to examine the structural relationship between the trachea, the vertebra, and the innominate artery periodically by 3 DCT.
Asunto(s)
Tronco Braquiocefálico/diagnóstico por imagen , Niños con Discapacidad , Fístula del Sistema Respiratorio/diagnóstico por imagen , Escoliosis/complicaciones , Tomografía Computarizada por Rayos X , Tráquea/diagnóstico por imagen , Fístula Vascular/diagnóstico por imagen , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Intensificación de Imagen Radiográfica , Fístula del Sistema Respiratorio/etiología , Escoliosis/diagnóstico por imagen , Traqueostomía/efectos adversos , Fístula Vascular/etiologíaRESUMEN
Cases of pulmonary infection caused by Mycobacterium kansasii (Mk) in our hospital located at the mid-northern area of the Kyushu district, which is in the southern part of Fukuoka prefecture were evaluated. Mk infection is not so rare in other areas of Japan, such as Tokyo and Kinki district, however, there has been no published report on the disease from the Kyusyu district. Therefore, the frequency and the clinical features of our cases of Mk infection were analyzed. During 17 years from 1982 to 1998, there were 14 patients of Mk infection out of 241 nontuberculous mycobacteriosis (NTM). There were 595 patients of culture-positive pulmonary tuberculosis without prior treatment (Tbc). The proportion of Mk/Tbc was 2.4% and that of Mk/NTM was 5.8%. During the period A (from 1982 to 1994) the ratio of Mk/Tbc was 5/462 (1.1%), while on the other side that of Mk/Tbc during the period B (from 1995 to 1998), it was 9/133 (6.8%), which was significantly (P < 0.01) higher compared with that in the period A. Although the patients of Mk infection in our hospital had been rare until 1994, from the results mentioned above, it was considered that the frequency of Mk infection in our hospital has increased to some extent since 1995. One of the characteristics in our cases was that the ratio of female (42.9%) was relatively high. All the female patients were considered to be compromised hosts. The results of the drug resistance tests were consistent with the other reports in our country. By the combination treatment including rifampicin as the major drug, the negative conversion of culture were obtained within 2 months in all our cases.
Asunto(s)
Infecciones por Mycobacterium no Tuberculosas/epidemiología , Mycobacterium kansasii , Tuberculosis Pulmonar/epidemiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Infecciones por Mycobacterium no Tuberculosas/microbiología , Factores Sexuales , Factores de Tiempo , Tuberculosis Pulmonar/microbiologíaRESUMEN
By using Western blot and RT-PCR analyses, the expression of ClC-5, a member of the ClC family of voltage-gated chloride channels, and its mRNA was detected in OK cells. The effect of chloride channel inhibitors on receptor-mediated endocytosis of albumin was examined in OK cells and compared to that of vacuolar H(+)-ATPase inhibitors. Accumulation of fluorescein-isothiocyanate (FITC)-albumin, a receptor-mediated endocytosis marker, was inhibited by 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB), a chloride channel inhibitor, in a concentration-dependent fashion. In contrast, uptake of FITC-inulin, a fluid-phase endocytosis marker, was not affected by NPPB. Other chloride channel inhibitors, 4,4'-diisothiocyanatostilbene-2-2'-disulfonic acid and diphenylamine-2-carboxylic acid, also inhibited FITC-albumin uptake. NPPB, as well as a vacuolar H(+)-ATPase inhibitor bafilomycin A(1), caused a decrease in the affinity and in the maximal velocity of FITC-albumin uptake. These results suggest that chloride channel, most likely ClC-5, plays an important role in the receptor-mediated endocytosis of albumin in OK cells.
Asunto(s)
Albúminas/metabolismo , Canales de Cloruro/genética , Endocitosis/fisiología , Receptores de Superficie Celular/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , Canales de Cloruro/fisiología , Fluoresceína-5-Isotiocianato , Cinética , Datos de Secuencia Molecular , Zarigüeyas , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
A new transthyretin (TTR) variant (lysine 92), which causes late onset cardiac amyloidosis, is described in a 71-year-old man. The patient at first had syncope due to ventricular tachycardia and was admitted our hospital. Typical findings of cardiac amyloidosis were observed by echocardiography, and a diagnosis of systemic amyloidosis was made by rectal biopsy. The man died approximately 3 years and 6 months after first admission, with gradually worsening congestive heart failure. Pathological examination showed prominent amyloid deposits in the heart and the vascular wall of many organs including the liver, pancreas, kidney, lung, and gastrointestinal tracts. Amyloid protein of transthyretin type was indicated by immunohistochemical study, and DNA sequencing identified a novel mutation in the transthyretin gene encoding 92 glutamine --> lysine. A polymerase chain reaction-induced mutation restriction analysis with a mismatched antisense primer showed that the patient was heterozygous for the TTR Lys92 allele.