RESUMEN
BACKGROUND: In older patients with progressive neurodegeneration, replacing fixed implant-supported prostheses (FIP) with implant overdentures (IOD) has been proposed to prevent future mucosal injury and create an oral environment that is easier for caregivers to clean. However, there have been no reports on the progress after replacing FIP with IOD. In this report, we present the progress of an older patient with Parkinson's disease in whom FIP was replaced with IOD. CASE PRESENTATION: An 81-year-old male patient with Parkinson's disease presented to our outpatient clinic with bruxism and crossbites. FIPs, with five Brånemark system implants, were placed in the bilateral lower molars. The FIP was replaced with an IOD with two locator attachments to create an oral environment that was easier for caregivers to clean and allow easy recovery of masticatory function if residual teeth were fractured in the care environment. As his systemic condition deteriorated, treatment was changed from outpatient to in-home visits. During dental care visits, professional oral cleaning and denture repair were continued, and good nutritional status was maintained. However, the patient developed cholecystitis and was hospitalized. During hospitalization, gastrostomy was performed because he developed aspiration pneumonia. After discharge from the hospital, the patient remained in bed all day and could not wear an IOD, resulting in buccal mucosa ulceration due to abrasion of the locator abutment. We decided to replace the abutment with cover screws; however, not all the implants could sleep submucosally. Although regular oral cleaning was resumed, new ulcers developed even when cover screws were installed. Additionally, swelling and drainage were observed at the peri-implant mucosal site where peri-implantitis had once occurred during an outpatient visit. The patient was readmitted to the hospital for a urinary tract infection, and subsequent visits were abandoned. CONCLUSIONS: By replacing FIP with IOD in an older patient with Parkinson's disease, we addressed a barrier to caregiver-provided oral management. The removable prosthesis facilitated smooth oral care by caregivers and functional recovery in the event of trouble with residual teeth. However, it could not completely avoid the recurrence of buccal mucosal ulcers or peri-implantitis.
Asunto(s)
Prótesis Dental de Soporte Implantado , Prótesis de Recubrimiento , Enfermedad de Parkinson , Humanos , Masculino , Anciano de 80 o más Años , Estudios de SeguimientoRESUMEN
PURPOSE: This prospective cohort study examined the effects of the number of present and functional teeth on mortality among older Japanese adults requiring nursing care in an environment of comprehensive oral hygiene and nutritional management. METHODS: The study included 174 older adults (mean age: 84.4 ± 8.3 years; male/female: 49/125) in need of support or long-term care, who resided in either a local specialized healthcare facility or their own homes, and received daily oral hygiene and nutritional support at facilities in Okayama, Japan. The initial clinical oral examination along with assessment of general physical condition and nursing environment of the participants were performed in July 2013 and followed up for one year. RESULTS: All-cause mortality occurred in 28 (mean age: 88.7 ±13.4 years; male/female: 6 /22) individuals during the follow-up period. Cox proportional hazard analysis indicated that older age, low performance in activities of daily living (Barthel Index <40), and underweight status (body mass index <18.5) were significant risk factors for mortality. The number of present and functional teeth were not found to be significant risk factors for mortality. CONCLUSIONS: During the one-year follow-up period, the number of present and functional teeth did not have a significant impact on mortality among older Japanese adults requiring nursing care in a well-managed environment of oral hygiene and nutritional status.
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Actividades Cotidianas , Longevidad , Higiene Bucal , Humanos , Femenino , Masculino , Estudios Prospectivos , Anciano de 80 o más Años , Anciano , Japón , Factores de Riesgo , Atención de Enfermería , Cuidados a Largo Plazo , Estudios de Cohortes , Estudios de Seguimiento , Modelos de Riesgos Proporcionales , Pérdida de Diente , DienteRESUMEN
CONTEXT: Mutations in the GH1 gene have been identified in patients with isolated growth hormone deficiency (IGHD). Mutations causing aberrant splicing of exon 3 of GH1 that have been identified in IGHD are inherited in an autosomal dominant manner, whereas other mutations in GH1 that have been identified in IGHD are inherited in an autosomal recessive manner. OBJECTIVE: Two siblings born from nonconsanguineous healthy parents exhibited IGHD. To elucidate the cause, GH1 in all family members was analysed. RESULTS: Two novel mutations in GH1, a point mutation in intron 3 and a 16-bp deletion in exon 3, were identified by sequence analyses. The intronic mutation was present in both siblings and was predicted to cause aberrant splicing. The deletion was present in one of the siblings as well as the mother with normal stature and was predicted to cause rapid degradation of mRNA through nonsense-mediated mRNA decay. The point mutation was not identified in the parents' peripheral blood DNA; however, it was detected in the DNA extracted from the father's sperms. As a trace of the mutant allele was detected in the peripheral blood of the father using PCR-RFLP, the mutation is likely to have occurred de novo at an early developmental stage before differentiation of somatic cells and germline cells. CONCLUSIONS: This is the first report of mosaicism for a mutation in GH1 in a family with IGHD. It is clear that the intronic mutation plays a dominant role in the pathogenesis of IGHD in this family, as one of the siblings who had only the point mutation was affected. On the other hand, the other sibling was a compound heterozygote for the point mutation and the 16-bp deletion and it may be arguable whether IGHD in this patient should be regarded as autosomal dominant or recessive.
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Hormona de Crecimiento Humana/deficiencia , Hormona de Crecimiento Humana/genética , Mosaicismo , Mutación , Secuencia de Bases , Preescolar , Análisis Mutacional de ADN , Padre , Femenino , Humanos , Lactante , Masculino , Datos de Secuencia Molecular , Linaje , Sitios de Empalme de ARN/genética , Eliminación de Secuencia , HermanosRESUMEN
PURPOSE: We aimed to determine root caries annual incidence (RCAI) and root caries annual progression (RCAP) and risk factors for them among older people requiring nursing care. METHODS: The target population comprised 186 dentate individuals aged ≥ 65 years who required nursing care while living in nursing homes (NHs) or their own homes (OHs) in Okayama, Japan. Survey items included presence/absence and severity of root caries, age, sex, living environment (NH or OH), the Clinical Dementia Rating, and the Barthel Index (BI). Baseline surveys were conducted from 2015 to 2017; subjects were followed up for one year. RCAI and RCAP per tooth and per person were calculated, and risk factors for them were identified using generalized estimating equations. RESULTS: In total, 104 individuals (mean age: 82.0 ± 12.4 years) completed the follow-up survey. RCAIs per tooth and per person were 14.6% (173/1188) and 59.6% (62/104), respectively. RCAP per tooth was 22.5% (51/227 teeth with root caries at baseline). Significant risk factors for RCAI were living environment (OH, odds ratio [OR]: 2.14), sex (male, OR: 1.84), clasped tooth (OR: 1.82), and older age (OR: 1.05) at baseline. Significant risk factors for RCAP were sex (male, OR: 5.20), regular dental checkup (OR: 2.74), and high BI score (OR: 1.02) at baseline. CONCLUSION: At one-year follow-up, 59.6% of the subjects developed at least one root caries. Risk factors for RCAI were living environment (OH), male, clasped tooth, and older age, whereas those for RCAP were male, regular dental checkup, and high BI score.
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Caries Dental , Caries Radicular , Anciano , Anciano de 80 o más Años , Caries Dental/epidemiología , Femenino , Humanos , Incidencia , Masculino , Estudios Prospectivos , Factores de Riesgo , Caries Radicular/epidemiologíaRESUMEN
(1) Background: Protein stimulates the secretion of glucagon (GCG), which can affect glucose metabolism. This study aimed to analyze the metabolic effect of a high-protein diet (HPD) in the presence or absence of proglucagon-derived peptides, including GCG and GLP-1. (2) Methods: The response to HPD feeding for 7 days was analyzed in mice deficient in proglucagon-derived peptides (GCGKO). (3) Results: In both control and GCGKO mice, food intake and body weight decreased with HPD and intestinal expression of Pepck increased. HPD also decreased plasma FGF21 levels, regardless of the presence of proglucagon-derived peptides. In control mice, HPD increased the hepatic expression of enzymes involved in amino acid metabolism without the elevation of plasma amino acid levels, except branched-chain amino acids. On the other hand, HPD-induced changes in the hepatic gene expression were attenuated in GCGKO mice, resulting in marked hyperaminoacidemia with lower blood glucose levels; the plasma concentration of glutamine exceeded that of glucose in HPD-fed GCGKO mice. (4) Conclusions: Increased plasma amino acid levels are a common feature in animal models with blocked GCG activity, and our results underscore that GCG plays essential roles in the homeostasis of amino acid metabolism in response to altered protein intake.
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Dieta Rica en Proteínas , Glucagón , Animales , Glucagón/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Ratones , Péptidos , Proglucagón/genética , Proglucagón/metabolismoRESUMEN
In the 1990s, interprofessional education (IPE) was introduced to health professionals in higher education; it has come to be regarded as a standard learning method. However, major barriers remain regarding its introduction and smooth operation. This study conducted a questionnaire survey at educational facilities for health professionals in Japan; it developed scales to measure the recognition of barriers to and benefits of IPE implementation. We surveyed chairpersons responsible for 2,690 courses in Japanese health education facilities. We used for analysis the responses related to 767 courses (valid response rate, 28.5%). In all, 216 courses (28.7%) implemented IPE. We conducted exploratory factor analysis and developed scales for measuring the recognition of barriers to IPE implementation (15 items) and its benefits (11 items). We observed a significant relationship between the state of IPE implementation and recognition of barriers to and benefits of IPE. Using information and communication technology and faculty development for faculty members would be effective in removing the barriers to IPE implementation.
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Educación Interprofesional , Relaciones Interprofesionales , Curriculum , Empleos en Salud , Humanos , JapónRESUMEN
The co-occurrence of resistance to thyroid hormone beta (RTHß) and myotonic dystrophy type 1 (DM1) was observed in a Japanese family. Two mutations, P453A and C36Y, were identified in the thyroid hormone receptor beta (THRB) gene. Whereas family members with THRBP453A exhibited RTHß, two members with THRBC36Y but without THRBP453A had normal thyroid function. Two members, one with RTHß and the other without, had a triplet expansion in the dystrophia myotonia protein kinase gene, a hallmark of DM1. The member with both RTHß and DM1 developed atrial fibrillation at the age of 16 years, suggesting a synergistic impact on the heart.
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Mutación , Distrofia Miotónica/genética , Proteína Quinasa de Distrofia Miotónica/genética , Receptores beta de Hormona Tiroidea/genética , Síndrome de Resistencia a Hormonas Tiroideas/genética , Repeticiones de Trinucleótidos , Adolescente , Adulto , Fibrilación Atrial/etiología , Aleteo Atrial/etiología , Femenino , Predisposición Genética a la Enfermedad , Herencia , Humanos , Masculino , Persona de Mediana Edad , Distrofia Miotónica/complicaciones , Distrofia Miotónica/diagnóstico , Linaje , Fenotipo , Síndrome de Resistencia a Hormonas Tiroideas/complicaciones , Síndrome de Resistencia a Hormonas Tiroideas/diagnósticoRESUMEN
OBJECTIVE: To characterize the cause of a sporadic isolated growth hormone deficiency in a single patient. METHODS: Genomic DNA was extracted from blood samples of the patient and his family. Exons and exon-intron junctions of the GH-1 gene were amplified by PCR and sequenced. To characterize possible GH-1 deletions we performed Southern blot analysis and PCR-restriction fragment length analyses. RESULTS: An adenine to guanine mutation at the first nucleotide of the initiation codon (Met [ATG](-26)Val [GTG]) of the GH-1 gene was identified in the patient and the mother. A 7.6kb GH-1 deletion was identified in the patient, the brother and the father. CONCLUSION: The patient was a compound heterozygote for an allele bearing a Met(-26)Val missense mutation inherited from his mother and an allele containing deletion of the entire GH-1 gene inherited from his father. The present missense mutation has not been described previously. Attention should be paid to the heterozygous gene deletion that is difficult to detect by PCR-based genetic analysis. The patient responded to GH replacement therapy fairly well, without developing anti-hGH antibody.
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Enanismo Hipofisario/genética , Heterocigoto , Hormona de Crecimiento Humana/genética , Alelos , Codón Iniciador/genética , Hormona de Crecimiento Humana/deficiencia , Humanos , Lactante , Masculino , Metionina/química , Metionina/genética , Mutación Missense , Linaje , Análisis de Secuencia de ADN , Valina/química , Valina/genéticaRESUMEN
Desmosterolosis is an autosomal recessive disorder due to mutations in the 3beta-hydroxysterol-Delta24 reductase (DHCR24) gene that encodes an enzyme catalyzing the conversion of desmosterol to cholesterol. To date, only two patients have been reported with severe developmental defects including craniofacial abnormalities and limb malformations. We employed mice with targeted disruption of DHCR24 to understand the pathophysiology of desmosterolosis. All DHCR24-/- mice died within a few hours after birth. Their skin was wrinkleless and less pliant, leading to restricted movement and inability to suck (empty stomach). DHCR24 gene was expressed abundantly in the epidermis of control but not of DHCR24-/- mice. Accordingly, cholesterol was not detected whereas desmosterol was abundant in the epidermis of DHCR24-/- mice. Skin histology revealed thickened epidermis with few and smaller keratohyaline granules. Aberrant expression of keratins such as keratins 6 and 14 suggested hyperproliferative hyperkeratosis with undifferentiated keratinocytes throughout the epidermis. Altered expression of filaggrin, loricrin, and involcrin were also observed in the epidermis of DHCR24-/-. These findings suggested impaired skin barrier function. Indeed, increased trans-epidermal water loss and permeability of Lucifer yellow were observed in DHCR24-/- mice. DHCR24 thus plays crucial role for skin development and its proper function.
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Desmosterol/metabolismo , Proteínas del Tejido Nervioso/fisiología , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/fisiología , Enfermedades de la Piel/etiología , Piel/patología , Animales , Apoptosis , Caveolina 1/análisis , Diferenciación Celular , Proliferación Celular , Ceramidas/análisis , Colesterol/biosíntesis , Ácidos Grasos no Esterificados/análisis , Inmunohistoquímica , Queratinocitos/citología , Queratinas/análisis , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía Electrónica , Proteínas del Tejido Nervioso/genética , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/genética , Permeabilidad , Piel/metabolismo , Enfermedades de la Piel/patologíaRESUMEN
BACKGROUND: Various mutations of the growth hormone releasing hormone receptor (GHRH-R) gene have been recently described to cause familial isolated growth hormone (GH) deficiency (FIGHD), with the GHRH-R nonsense mutation E72X reported in patients with FIGHD from South Asia. The molecular genetic basis of FIGHD in Indian children is not known. OBJECTIVE: To look for the GHRH-R E72X non-sense mutation in our patients with FIGHD and describe its clinical phenotype. PATIENTS AND METHOD: A total of 31 patients from 22 families diagnosed 4-20 years previously, 20 patients with familial IGHD-IB from 11 families and 11 patients with non-familial isolated GH deficiency (NFIGHD) (phenotypes IGHD-IB in eight patients and -IA in three) were included. Twenty-eight of 31 patients with IGHD-IB came from two states of Western India, 27 of them Hindus from 18 families (three consanguineous) and one from an inbred Moslem kindred. RESULTS: Twenty-two of the patients (71%) (18 FIGHD and four NFIGHD) had a homozygous G-->T transversion in exon 3, with this GHRH-R gene mutation E72X in 90% (18/20) of patients with FIGHD, 36% (4/11) of NFIGHD, altogether 78% (22/28) with phenotype IB. One parent pair with IGHD had homozygous E72X mutation, the rest were heterozygous carriers. Two siblings with IGHD due to homozygous E72X mutation were also heterozygous carriers for GH-1 gene 6.7 kb deletion, inherited from their mother, heterozygous for both GH-1 and GHRH-R mutations. Initial chronological age was 10.89 +/- 3.69 years, bone age 6.4 +/- 3.4 years, and mean height SDS was -5.83 +/- 1.41. The clinical phenotype, with sharp features, lean habitus, lack of frontal bossing or hypoglycemia, was characteristic. The mean peak GH was 1.25 +/- 0.75 ng/ml, IGF-I and IGFBP-3 below -2 SDS with no response to GHRH in those tested. MRI (n = 10) showed pituitary hypoplasia, mean vertical height 2.61 +/- 0.76 mm. Among the other 7/11 NFIGHD patients, four with phenotype IB were negative for genotypes tested in this study; of three patients with phenotype IA, two had the GH-1 gene 6.7 kb deletion, and one was a compound heterozygote with 6.7 and 7.6 kb deletions. CONCLUSIONS: The majority of patients with FIGHD from different communities belonged to non-consanguineous Hindu families from Western India. The GHRH-R gene E72X mutation was found in 71% of this series, in 90% of FIGHD, 36% of NFIGHD, and in 78% with phenotype IB. The characteristic phenotype helped in suspecting this mutation. GHRH-R gene mutations may be the most reasonable candidate for IGHD-IB with the E72X mutation predominating in the Indian subcontinent. More extensive studies need to be undertaken.
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Codón sin Sentido , Enanismo Hipofisario/genética , Predisposición Genética a la Enfermedad , Hormona de Crecimiento Humana/deficiencia , Receptores de Neuropéptido/genética , Receptores de Hormona Reguladora de Hormona Hipofisaria/genética , Adolescente , Adulto , Niño , Preescolar , Enanismo Hipofisario/etnología , Enanismo Hipofisario/patología , Femenino , Hinduismo , Humanos , India/epidemiología , Lactante , Islamismo , Masculino , Persona de Mediana Edad , Linaje , Estudios RetrospectivosRESUMEN
An identical nonsense mutation (E72X) in growth hormone releasing hormone receptor (GHRHR) gene was identified in 17 patients with isolated GH deficiency belonging to one Muslim and four Hindu families residing in the Western part of India. Analysis of two dinucleotide repeat polymorphism, one at 6 kb downstream and the other at 13 kb downstream of GHRHR gene, revealed that all the patients shared the same homozygotic alleles at both loci. These results strongly indicate that the nonsense mutation occurred in a single ancestor and was subsequently transmitted to the descendants. This GHRHR mutation may be an important cause of familial IGHD in Western India and Sindh area of Pakistan as previous studies have also reported the same mutation.
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Codón sin Sentido , Repeticiones de Dinucleótido/fisiología , Efecto Fundador , Hormona de Crecimiento Humana/deficiencia , Polimorfismo Genético , Receptores de Neuropéptido/genética , Receptores de Hormona Reguladora de Hormona Hipofisaria/genética , Adolescente , Adulto , Secuencia de Bases , Niño , Humanos , India , Datos de Secuencia Molecular , LinajeRESUMEN
Glucagon and glucagon-like peptide-1 (GLP-1) are produced in pancreatic α-cells and enteroendocrine L-cells, respectively, in a tissue-specific manner from the same precursor, proglucagon, that is encoded by glucagon gene (Gcg), and play critical roles in glucose homeostasis. Here, we studied glucose homeostasis and ß-cell function of Gcg-deficient mice that are homozygous for a Gcg-GFP knock-in allele (Gcg(gfp/gfp)). The Gcg(gfp/gfp) mice displayed improved glucose tolerance and enhanced insulin secretion, as assessed by both oral glucose tolerance test (OGTT) and intraperitoneal glucose tolerance test (IPGTT). Responses of glucose-dependent insulinotropic polypeptide (GIP) to both oral and intraperitoneal glucose loads were unexpectedly enhanced in Gcg(gfp/gfp) mice, and immunohistochemistry localized GIP to pancreatic ß-cells of Gcg(gfp/gfp) mice. Furthermore, secretion of GIP in response to glucose was detected in isolated islets of Gcg(gfp/gfp) mice. Blockade of GIP action in vitro and in vivo by cAMP antagonism and genetic deletion of the GIP receptor, respectively, almost completely abrogated enhanced insulin secretion in Gcg(gfp/gfp) mice. These results indicate that ectopic GIP expression in ß-cells maintains insulin secretion in the absence of proglucagon-derived peptides (PGDPs), revealing a novel compensatory mechanism for sustaining incretin hormone action in islets.
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Polipéptido Inhibidor Gástrico/biosíntesis , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Fragmentos de Péptidos/metabolismo , Proglucagón/metabolismo , Animales , AMP Cíclico/antagonistas & inhibidores , Polipéptido Inhibidor Gástrico/genética , Eliminación de Gen , Técnicas de Sustitución del Gen , Receptor del Péptido 1 Similar al Glucagón , Intolerancia a la Glucosa/genética , Intolerancia a la Glucosa/metabolismo , Prueba de Tolerancia a la Glucosa , Homeostasis/genética , Homeostasis/fisiología , Inmunohistoquímica , Incretinas/metabolismo , Secreción de Insulina , Células Secretoras de Insulina/citología , Masculino , Ratones , Proglucagón/análisis , Receptores de la Hormona Gastrointestinal/genética , Receptores de Glucagón/metabolismoRESUMEN
Proglucagon, which is encoded by the glucagon gene (Gcg), is the precursor of several peptide hormones, including glucagon and glucagon-like peptide 1 (GLP-1). Whereas glucagon stimulates hepatic glycogenolysis and gluconeogenesis, GLP-1 stimulates insulin secretion to lower blood glucose and also supports ß-cell proliferation and protection from apoptotic stimuli. Pregnancy is a strong inducer of change in islet function, however the roles of proglucagon-derived peptides in pregnancy are only partially understood. In the present study, we analyzed fertility and pregnancy-associated changes in homozygous glucagon-green fluorescent protein (gfp) knock-in mice (Gcg(gfp/gfp)), which lack all the peptides derived from proglucagon. Female Gcg(gfp/gfp) mice could deliver and raise Gcg(gfp/gfp) pups to weaning and Gcg(gfp/gfp) pups from Gcg(gfp/gfp) dams were viable and fertile. Pregnancy induced ß-cell proliferation in Gcg(gfp/gfp) mice as well as in control mice. However, serum insulin levels in pregnant Gcg(gfp/gfp) females were lower than those in control pregnant females under ad libitum feeding, and blood glucose levels in pregnant Gcg(gfp/gfp) females were higher after gestational day 12. Gcg(gfp/gfp) females showed a decreased pregnancy rate and smaller litter size. The rate of successful breeding was significantly lower in Gcg(gfp/gfp) females and was not improved by experience of breeding. Taken together, proglucagon-derived peptides are not required for pregnancy-associated ß-cell proliferation, however, are required for regulation of blood glucose levels and normal reproductive capacity. Gcg(gfp/gfp) mice may serve as a novel model to analyze the effect of mild hyperglycemia during late gestational periods.
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Fertilidad , Células Secretoras de Insulina/citología , Fragmentos de Péptidos/metabolismo , Proglucagón/química , Animales , Glucemia/metabolismo , Proliferación Celular , Tamaño de la Célula , Femenino , Técnicas de Sustitución del Gen , Genotipo , Insulina/sangre , Células Secretoras de Insulina/metabolismo , Ratones , Embarazo , Proglucagón/genética , Conducta Sexual AnimalRESUMEN
Glucagon is believed to be one of the most important peptides for upregulating blood glucose levels. However, homozygous glucagon-green fluorescent protein (gfp) knock-in mice (Gcg(gfp/gfp): GCGKO) are normoglycemic despite the absence of proglucagon-derived peptides, including glucagon. To characterize metabolism in the GCGKO mice, we analyzed gene expression and metabolome in the liver. The expression of genes encoding rate-limiting enzymes for gluconeogenesis was only marginally altered. On the other hand, genes encoding enzymes involved in conversion of amino acids to metabolites available for the tricarboxylic acid cycle and/or gluconeogenesis showed lower expression in the GCGKO liver. The expression of genes involved in the metabolism of fatty acids and nicotinamide was also altered. Concentrations of the metabolites in the GCGKO liver were altered in manners concordant with alteration in the gene expression patterns, and the plasma concentrations of amino acids were elevated in the GCGKO mice. The insulin concentration in serum and phosphorylation of Akt protein kinase in liver were reduced in GCGKO mice. These results indicated that proglucagon-derived peptides should play important roles in regulating various metabolic pathways, especially that of amino acids. Serum insulin concentration is lowered to compensate the impacts of absent proglucagon-derived peptide on glucose metabolism. On the other hand, impacts on other metabolic pathways are only partially compensated by reduced insulin action.
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Aminoácidos/sangre , Hígado/metabolismo , Enfermedades Metabólicas/metabolismo , Proglucagón/deficiencia , Proglucagón/genética , Aminoácidos/metabolismo , Animales , Regulación Enzimológica de la Expresión Génica , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Metabolismo de los Lípidos/genética , Metabolismo de los Lípidos/fisiología , Hígado/enzimología , Masculino , Enfermedades Metabólicas/sangre , Enfermedades Metabólicas/genética , Redes y Vías Metabólicas/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Modelos Biológicos , Fragmentos de Péptidos/química , Fragmentos de Péptidos/deficiencia , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Proglucagón/química , Proglucagón/metabolismo , Regulación hacia ArribaRESUMEN
Multiple bioactive peptides, including glucagon, glucagon-like peptide-1 (GLP-1), and GLP-2, are derived from the glucagon gene (Gcg). In the present study, we disrupted Gcg by introduction of GFP cDNA and established a knock-in mouse line. Gcg(gfp/gfp) mice that lack most, if not all, of Gcg-derived peptides were born in an expected Mendelian ratio without gross abnormalities. Gcg(gfp/gfp) mice showed lower blood glucose levels at 2 wk of age, but those in adult Gcg(gfp/gfp) mice were not significantly different from those in Gcg(+/+) and Gcg(gfp/+) mice, even after starvation for 16 h. Serum insulin levels in Gcg(gfp/gfp) mice were lower than in Gcg(+/+) and Gcg(gfp/+) on ad libitum feeding, but no significant differences were observed on starvation. Islet alpha-cells and intestinal L-cells were readily visualized in Gcg(gfp/gfp) and Gcg(gfp/+) mice under fluorescence. The Gcg(gfp/gfp) postnatally developed hyperplasia of islet alpha-cells, whereas the population of intestinal L-cells was not increased. In the Gcg(gfp/gfp), expression of Aristaless-related homeobox (Arx) was markedly increased in pancreas but not in intestine and suggested involvement of Arx in differential regulation of proliferation of Gcg-expressing cells. These results illustrated that Gcg-derived peptides are dispensable for survival and maintaining normoglycemia in adult mice and that Gcg-derived peptides differentially regulate proliferation/differentiation of alpha-cells and L-cells. The present model is useful for analyzing glucose/energy metabolism in the absence of Gcg-derived peptides. It is useful also for analysis of the development, differentiation, and function of Gcg-expressing cells, because such cells are readily visualized by fluorescence in this model.