RESUMO
Ferulic acid (FA) is a phytochemical compound with various physiologic functions. To clarify the effect of FA intake on skin barrier function (SBF), we conducted a placebo-controlled double-blind pilot trial. Sixteen healthy subjects were divided into 2 groups (n = 8) and ingested capsules containing either FA (200 mg) or placebo daily for 2 weeks. Two measures of SBF, transepidermal water loss and stratum corneum hydration, were assessed before and 2 weeks after the start of the study. Autonomic nervous activity, which is suggested to be related to SBF, was also measured. Compared with the values obtained before the start of the study, FA intake significantly reduced transepidermal water loss (from 6.1 ± 1.1 to 4.8 ± 1.0 g/m2/h, p = 0.005) and increased stratum corneum hydration (from 30.1 ± 7.6 to 32.3 ± 8.1 a.u., p = 0.027) after 2 weeks. In addition, the amount change in sympathetic nervous activity was significantly reduced after ingesting the FA capsules compared with the placebo capsules (-0.7 ± 1.6 vs. 1.1 ± 1.4, p = 0.035). These findings suggest that FA supplementation decreases sympathetic nervous activity and strengthens SBF in healthy men.
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Pele , Água , Masculino , Humanos , Cápsulas , Suplementos NutricionaisRESUMO
The effect of chlorogenic acid-enriched green coffee bean extract (cGCE) intake on arterial stiffness was investigated using the cardio-ankle vascular index (CAVI) as a novel surrogate marker for predicting arteriosclerosis. A placebo-controlled double-blind pilot study was conducted with 16 healthy Japanese men. Subjects were divided into two groups and consumed beverages containing either cGCE or placebo daily for 2 weeks. The CAVI, the primary endpoint of the study, was evaluated at the beginning of the study and 2 weeks later. Endothelium-dependent flow-mediated dilation (FMD) and sympathetic nervous activity (SNA), which are thought to be related to the CAVI, were also measured. The CAVI change was significantly greater in the cGCE group than in the placebo group. In addition, FMD increased and SNA decreased in the cGCE group. These findings suggest that 2-week ingestion of cGCE may improve arterial stiffness as assessed by the CAVI.
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Ácido Clorogênico/farmacologia , Café/química , Extratos Vegetais/farmacologia , Rigidez Vascular/efeitos dos fármacos , Adulto , Tornozelo , Índice Tornozelo-Braço , Arteriosclerose , Pressão Sanguínea/efeitos dos fármacos , Índice de Massa Corporal , Doenças Cardiovasculares , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Sistema Nervoso Simpático/efeitos dos fármacosRESUMO
Glycosphingolipids are expressed on the cell membrane and act as important factors in various events that occur across the plasma membrane. Lactosylceramide (LacCer) is synthesized from glucosylceramide and is a common precursor of various glycosphingolipids existing in whole body. Based on the enzyme purification, ß1,4-galactosyltransferase 6 (B4galt6) cDNA was isolated as a LacCer synthase-coding gene in the rat brain. We generated B4galt6 gene knockout (KO) mice and analyzed their phenotypes to examine roles of ß4GalT6. B4galt6 KO mice were born and grew up apparently normal. LacCer synthase activity and the composition of acidic glycosphingolipids in the brain were almost equivalent or minimally different between wild-type and KO mice. Studies by mouse embryonic fibroblasts (MEFs) revealed that the silencing of B4galt5 gene resulted in the marked reduction in LacCer synthase activity and this reduction was more severe in MEFs derived from B4galt6 KO mice than those from wild-type mice. These results suggested that ß4GalT6 plays a role as a LacCer synthase, whereas ß4GalT5 acts as a main enzyme for LacCer biosynthesis in these tissues and cells.
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Galactosiltransferases/metabolismo , Lactosilceramidas/biossíntese , Animais , Encéfalo/metabolismo , Linhagem Celular , Galactosiltransferases/genética , Lactosilceramidas/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , FenótipoRESUMO
O-linked-ß-N-acetylglucosamine (O-GlcNAc) modification is a unique cytoplasmic and nuclear protein modification that is common in nearly all eukaryotes, including filamentous fungi, plants, and animals. We had recently reported that epidermal growth factor (EGF) repeats of Notch and Dumpy are O-GlcNAcylated by an atypical O-GlcNAc transferase, EOGT, in Drosophila. However, no study has yet shown whether O-GlcNAcylation of extracellular proteins is limited to insects such as Drosophila or whether it occurs in other organisms, including mammals. Here, we report the characterization of A130022J15Rik, a mouse gene homolog of Drosophila Eogt (Eogt 1). Enzymatic analysis revealed that Eogt1 has a substrate specificity similar to that of Drosophila EOGT, wherein the Thr residue located between the fifth and sixth conserved cysteines of the folded EGF-like domains is modified. This observation is supported by the fact that the expression of Eogt1 in Drosophila rescued the cell-adhesion defect caused by Eogt downregulation. In HEK293T cells, Eogt1 expression promoted modification of Notch1 EGF repeats by O-GlcNAc, which was further modified, at least in part, by galactose to generate a novel O-linked-N-acetyllactosamine structure. These results suggest that Eogt1 encodes EGF domain O-GlcNAc transferase and that O-GlcNAcylation reaction in the secretory pathway is a fundamental biochemical process conserved through evolution.
Assuntos
Acetilglucosamina/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Receptores Notch/metabolismo , Sequência de Aminoácidos , Animais , Drosophila melanogaster/enzimologia , Evolução Molecular , Expressão Gênica , Células HEK293 , Humanos , Camundongos , Dados de Sequência Molecular , N-Acetilglucosaminiltransferases/química , N-Acetilglucosaminiltransferases/genéticaRESUMO
OBJECTIVE: To evaluate longitudinal changes in parotid volumes and saliva production over 2 years after 30 Gy irradiation. METHODS: We retrospectively evaluated 15 assessable patients treated for advanced oral cancer. Eligibility criteria were a pathologic diagnosis of squamous cell carcinoma, preoperative radiation therapy with a total dose of 30 Gy delivered in 15 fractions, and the availability of longitudinal data of morphological assessments by computed tomography and functional assessments with the Saxon test spanning 2 years after radiation therapy. In the Saxon test, saliva production was measured by weighing a folded sterile gauze pad before and after chewing; the low-normal value is 2 g/2 min. Repeated-measures analysis of variance with Bonferroni adjustment for multiple comparisons was used to determine the longitudinal changes. RESULTS: The normalized ipsilateral parotid volumes 2 weeks and 6-, 12- and 24 months after radiation therapy were found to be 72.5, 63.7, 66.9 and 78.1%, respectively; the normalized contralateral volumes were 69.8, 64.6, 72.2 and 82.0%, respectively. The bilateral parotid volumes were significantly decreased after radiation therapy (P < 0.01). The nadir appeared at 6 months post-radiation therapy and the volumes substantially recuperated 24 months after radiation therapy (P < 0.01). Mean saliva production before radiation therapy was 3.7 g; the longitudinal changes after radiation therapy were 31.3, 38.0, 43.3 and 69.6%, respectively. Substantial recuperation of saliva production was observed 24 months after radiation therapy (P = 0.01). CONCLUSIONS: Although parotid volumes and saliva production were decreased after 30 Gy irradiation, we observed the recuperation of morphological and functional changes in the parotid glands 2 years after radiation therapy.
Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Bucais/radioterapia , Terapia Neoadjuvante/métodos , Glândula Parótida/efeitos da radiação , Saliva/metabolismo , Saliva/efeitos da radiação , Xerostomia/etiologia , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/fisiopatologia , Carcinoma de Células Escamosas/cirurgia , Quimioterapia Adjuvante , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/diagnóstico por imagem , Neoplasias Bucais/patologia , Neoplasias Bucais/fisiopatologia , Neoplasias Bucais/cirurgia , Tamanho do Órgão/efeitos da radiação , Glândula Parótida/metabolismo , Glândula Parótida/patologia , Planejamento da Radioterapia Assistida por Computador , Radioterapia Adjuvante/efeitos adversos , Recuperação de Função Fisiológica , Estudos Retrospectivos , Fatores de Tempo , Tomografia Computadorizada por Raios X , Xerostomia/patologia , Xerostomia/fisiopatologiaRESUMO
BACKGROUND: The effects of exposure to hyperbaric oxygen on ultraviolet B (UVB) irradiation-induced melanin pigmentations of skins and on senile spot sizes of faces were investigated. METHODS: In the first experiment, male subjects were irradiated with UVB on their upper arms for inducing erythema and the subsequent melanin pigmentation. They were exposed to a hyperbaric environment at 1.25 atmospheres absolute (ATA) with 32% oxygen for 1 h/day, three times per week. In the second experiment, female subjects were exposed to a hyperbaric environment at 1.25 ATA with 32% oxygen for 1 h/day, two times per week. RESULTS: In the first experiment, melanin pigmentations lightened after 4 weeks of exposure to hyperbaric oxygen. In the second experiment, senile spot sizes became small after 12 weeks of exposure to hyperbaric oxygen. CONCLUSION: We concluded that exposure to hyperbaric oxygen used in this study accelerates both the fading in melanin pigmentation and the decrease in senile spot size.
Assuntos
Oxigenoterapia Hiperbárica/métodos , Melanose/etiologia , Melanose/terapia , Queimadura Solar/etiologia , Queimadura Solar/terapia , Raios Ultravioleta/efeitos adversos , Adulto , Feminino , Humanos , Lentigo/etiologia , Lentigo/patologia , Lentigo/terapia , Masculino , Melanose/patologia , Queimadura Solar/patologia , Resultado do TratamentoRESUMO
At present, there is no established cognitive behavioral therapy (CBT) for treating emotional disorders in Japanese children. Therefore, we introduced the Unified Protocol for Transdiagnostic Treatment of Emotional Disorders in Children (UP-C) in Japan and adapted it to the Japanese context. We then examined its feasibility and preliminary efficacy using a single-arm pretest, posttest, follow-up design. Seventeen Japanese children aged between 8 and 12 years (female n = 11; male n = 6; M = 10.06 ± 0.97 years) with a principal diagnosis of anxiety, obsessive-compulsive, or depressive disorders, and their parents were enrolled in the study. The primary outcome was the overall severity of emotional disorders as assessed by psychiatrists using the Clinical Global Impression-Severity Scale. Secondary outcomes included child- and parent-reported anxiety symptoms, depressive symptoms, and functional status. No severe adverse events were observed. The feasibility was confirmed by the low dropout proportion (11.76%), high attendance proportion (children: 95.6%; parents: 94.6%), and sufficient participant satisfaction. Linear mixed models (LMMs) showed that the overall severity of emotional disorders and child- and parent-reported anxiety symptoms improved from pre-treatment to post-treatment, and that these treatment effects were maintained during the 3-month follow-up period. Additionally, child- and parent-reported functional status improved from pre-treatment to the 3-month follow-up. In contrast, child-reported depressive symptoms improved from pre-treatment to follow-up, but there was no significant change in parent-reported depressive symptoms between pre-treatment and other time points. These findings demonstrate the feasibility and preliminary efficacy of the Japanese version of the UP-C, suggesting that future randomized controlled trials (RCTs) are warranted (Clinical trial registration: UMIN000026911).
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OBJECTIVE: To evaluate whether saliva production reflects the parotid volume during the course of radiation therapy (RT) in patients with head-and-neck cancer. METHODS: Twenty patients with advanced oral squamous cell carcinomas, who were treated with preoperative chemo-RT, underwent morphological assessment with CT or MRI and functional assessment with the Saxon test. For the Saxon test, saliva production was measured by weighing a gauze pad before and 2 min after chewing without swallowing; the low-normal value is 2 g. Saliva production and parotid volumes before and 2 weeks after RT were compared with the paired t-test, the Spearman rank correlation test and the Fisher exact test. RESULTS: After 30 Gy irradiation, mean saliva production was decreased from 4.2 to 1.0 g (P < 0.01); the reduction in saliva production ranged from 1.7 to 5.4 g (mean 3.2 g). The mean parotid volume was decreased from 68.2 to 47.9 cm(3) (P < 0.01); the post-RT:pre-RT parotid volume ratio ranged from 54% to 85% (mean 71%). Although the initial parotid ;volume was correlated with initial saliva production (r = 0.47, P = 0.04), no significant correlation was noted after RT (r = 0.08, P = 0.71), and there were considerable individual variations. The parotid volume ratio was inversely correlated with the saliva-reduction amount (r = - 0.79, P < 0.01). CONCLUSIONS: There was a correlation between decreased parotid gland volume and decreased saliva production in patients with head-and-neck cancer undergoing RT. Parotid volume reduction may predict parotid gland function.
Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Bucais/radioterapia , Glândula Parótida/efeitos da radiação , Saliva/metabolismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Glândula Parótida/metabolismo , Glândula Parótida/patologia , Estudos RetrospectivosRESUMO
The proliferation of epidermal basal cells decreases with age. This study examined the effects of exposure to mild hyperbaric oxygen on the proliferative activity of epidermal basal cells in aged mouse skin. Hairless mice aged 5, 34 and 55 weeks were exposed to mild hyperbaric oxygen at 1266 hPa with 36% oxygen for 6 h/day for 1 or 2 weeks. Skin samples were then collected from the back area to evaluate epidermal thickness and the number and proliferative activity of epidermal basal cells. Exposure to mild hyperbaric oxygen had no effect on the epidermal thickness, irrespective of age, but accelerated the proliferative activity of epidermal basal cells in aged mouse skin.
Assuntos
Proliferação de Células/efeitos dos fármacos , Oxigenoterapia Hiperbárica , Queratinócitos/efeitos dos fármacos , Oxigênio/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Epiderme/efeitos dos fármacos , Epiderme/fisiologia , Feminino , Humanos , Queratinócitos/fisiologia , Camundongos , Camundongos Pelados , Estresse Oxidativo/efeitos dos fármacos , Resultado do TratamentoRESUMO
Stereoselective synthesis of a potential intermediate bearing 11-oxabicyclo[6.2.1]undec-3-ene core, a common scaffold of biologically active germacrane-type sesquiterpenes, has been achieved. Synthetic features involve formal 1,3-asymmetric induction, unusual ring-closing metathesis constructing a 10-membered carbocycle system, and unique lactone transposition.
Assuntos
Compostos Bicíclicos com Pontes/química , Lactonas/síntese química , Sesquiterpenos/síntese química , Ciclização , Lactonas/química , Sesquiterpenos/químicaRESUMO
BACKGROUND: Cutaneous blood flow plays an important role in the thermoregulation, oxygen supply, and nutritional support necessary to maintain the skin. However, there is little evidence for a link between blood flow and skin physiology. Therefore, we conducted surveys of healthy volunteers to determine the relationship(s) between dry skin properties and cutaneous vascular function. METHODS: Water content of the stratum corneum, transepidermal water loss, and visual dryness score were investigated as dry skin parameters. Cutaneous blood flow in the resting state, the recovery rate (RR) of skin temperature on the hand after a cold-stress test, and the responsiveness of facial skin blood flow to local cooling were examined as indices of cutaneous vascular functions. The relationships between dry skin parameters and cutaneous vascular functions were assessed. RESULTS: The RR correlated negatively with the visual dryness score of skin on the leg but correlated positively with water content of the stratum corneum on the arm. No significant correlation between the resting state of blood flow and dry skin parameters was observed. In both the face and the body, deterioration in skin dryness from summer to winter was significant in subjects with low RR. The RR correlated well with the responsiveness of facial skin blood flow to local cooling, indicating that the RR affects systemic dry skin conditions. CONCLUSIONS: These results suggest that the RR but not blood flow at the resting state is associated with dry skin conditions and is involved in skin homeostasis during seasonal environmental changes.
Assuntos
Homeostase/fisiologia , Temperatura Cutânea/fisiologia , Pele/química , Estresse Fisiológico , Água/análise , Adolescente , Adulto , Fatores Etários , Idoso , Braço , Regulação da Temperatura Corporal , Bochecha , Temperatura Baixa , Capacitância Elétrica , Feminino , Humanos , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Estações do Ano , Pele/irrigação sanguínea , Perda Insensível de Água , Adulto JovemRESUMO
INTRODUCTION: trans-3,4'-Dimethyl-3-hydroxyflavanone (t-flavanone) is a derivative of astilbin that actively stimulates hair growth. The aim of the present study was to identify the mechanisms of action of t-flavanone on hair growth. METHODS: A double-blind usage test was performed with healthy volunteers who had androgenic alopecia (AGA). The subjects were divided into three groups with equal average baldness. The members in each group applied a vasodilator-containing hair lotion supplemented with either 0, 0.1, or 0.3% (wt) t-flavanone twice a day for 30 weeks. The efficacy of t-flavanone was evaluated based on the parietal global and microscopic images. At week 30, the anchoring strength of hair was measured by the average peak force required for plucking out a single hair in a non-bald area using a digital force gauge. Desmoglein expression in the cultured human hair follicle was analyzed by Western blotting. RESULTS: After 30 weeks, t-flavanone significantly improved AGA and enhanced the hair-anchoring strength in a hair diameter-independent manner. Culture of human hair follicles in vitro with t-flavanone resulted in the upregulation of desmoglein protein expression. CONCLUSIONS: The results of our in vivo and in vitro studies demonstrated that t-flavanone enhanced the cell-cell adhesions in hair follicles; thus, reinforcement of hair rooting may be a mechanism by which t-flavanone promotes hair growth. FUNDING: Kao Corp.
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Prefoldin is a chaperone that captures a protein-folding intermediate and transfers it to the group II chaperonin for correct folding. However, kinetics of interactions between prefoldin and substrate proteins have not been investigated. In this study, dissociation constants and dissociation rate constants of unfolded proteins with prefoldin were firstly measured using fluorescence microscopy. Our results suggest that binding and release of prefoldin from hyperthermophilic archaea with substrate proteins were in a dynamic equilibrium. Interestingly, the release of substrate proteins from prefoldin was facilitated when chaperonin was present, supporting a handoff mechanism of substrate proteins from prefoldin to the chaperonin.
Assuntos
Proteínas Arqueais/metabolismo , Chaperoninas/metabolismo , Chaperonas Moleculares/metabolismo , Pyrococcus horikoshii/metabolismo , Proteínas Arqueais/química , Chaperoninas/química , Citrato (si)-Sintase/química , Chaperonas Moleculares/química , Especificidade por SubstratoRESUMO
Although the lipoprotein lipase (LPL) activator NO-1886 shows antiobesity effects in high-fat-induced obese animals, the mechanism remains unclear. To clarify the mechanism, we studied the effects of NO-1886 on the expression of uncoupling protein (UCP) 1, UCP2, and UCP3 in rats. NO-1886 was mixed with a high-fat chow to supply a dose of 100 mg/kg to 8-month-old male Sprague-Dawley rats. The animals were fed the high-fat chow for 8 weeks. At the end of the administration period, brown adipose tissue (BAT), mesenteric fat, and soleus muscle were collected and levels of UCP1, UCP2, and UCP3 messenger RNA (mRNA) were determined. NO-1886 suppressed the body weight increase seen in the high-fat control group after the 8-week administration (585 +/- 39 vs 657 +/- 66 g, P < .05). NO-1886 also suppressed fat accumulation in visceral (46.9 +/- 10.4 vs 73.7 +/- 14.5 g, P < .01) and subcutaneous (43.1 +/- 18.1 vs 68.9 +/- 18.8 g, P < .05) tissues and increased the levels of plasma total cholesterol and high-density lipoprotein cholesterol in comparison to the high-fat control group. In contrast, NO-1886 decreased the levels of plasma triglycerides, nonesterified free fatty acid, glucose, and insulin. NO-1886 increased LPL activity in soleus muscle (0.082 +/- 0.013 vs 0.061 +/- 0.016 mumol of free fatty acid per minute per gram of tissue, P < .05). NO-1886 increased the expression of UCP3 mRNA in soleus muscle 3.14-fold (P < .01) compared with the high-fat control group without affecting the levels of UCP3 in mesenteric adipose tissue and BAT. In addition, NO-1886 did not affect the expression of UCP1 and UCP2 in BAT, mesenteric adipose tissue, and soleus muscle. In conclusion, NO-1886 increased the expression of UCP3 mRNA and LPL activity only in skeletal muscle. Therefore, a possible mechanism for NO-1886's antiobesity effects in rats may be the enhancement of LPL activity in skeletal muscle and the accompanying increase in UCP3 expression.
Assuntos
Tecido Adiposo/metabolismo , Fármacos Antiobesidade/farmacologia , Benzamidas/farmacologia , Proteínas de Transporte/genética , Gorduras na Dieta/administração & dosagem , Regulação da Expressão Gênica/efeitos dos fármacos , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Compostos Organofosforados/farmacologia , Animais , Glicemia/análise , Ingestão de Alimentos/efeitos dos fármacos , Insulina/sangue , Canais Iônicos , Lipase Lipoproteica/metabolismo , Masculino , Proteínas Mitocondriais , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Proteína Desacopladora 3 , Aumento de Peso/efeitos dos fármacosRESUMO
CA19-9 widely used as a tumor marker of the pancreas and a bile duct. There are a number of reports which describes the measured value discrepancies between RIA and non-RIA kits. RIA results also have shown lack of the linearity over 70 U/ml when the samples are diluted. The pH condition at assay reaction for RIA had been suggested as the major reason, it has been denied by the results from the same pH condition at assay reaction used by COBAS CORE CA19-9 EIA II. On the other hand, the lack of RIA antibody titer is indicated for the discordant results by changing the sample volume to reagent volume ratio in the reaction. Our further investigation also indicates that the specific Lewis blood type, i.e. Le (a-b+), shows the linearity issues by RIA. The discrepancies are not caused by the reaction pH, but the amount of the antibody used in the RIA kit is closely associated. Considering the CA19-9 antibody nature used in RIA kit, which covers broad molecular range, users need to pay more attention to setting up each laboratory's measuring range.
Assuntos
Antígenos de Neoplasias/sangue , Biomarcadores Tumorais/sangue , Anidrases Carbônicas/sangue , Radioimunoensaio/normas , Anidrase Carbônica IX , Humanos , Antígenos do Grupo Sanguíneo de Lewis , Radioimunoensaio/métodosRESUMO
We have investigated the physiological significance of the glucosylation of ceramides and the subsequent deglucosylation of glucosylceramide in the synthetic pathway of acylceramide. In this metabolic pathway using [14C]-serine in organ culture, newborn murine (BALB/c) epidermis synthesizes several types of ceramides, including acylceramide, as analyzed by thin-layer chromatography. When conduritol-B-epoxide, a specific inhibitor of beta-glucocerebrosidase, was added to the culture medium, the synthesis of acylceramide was significantly suppressed in concert with a significant increase in acylglucosylceramide. Furthermore, addition of d-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol, an inhibitor of glucosyltransferase, also specifically abolished the synthesis of acylceramide whereas non-acylated ceramides were relatively less affected. We further determined whether the physiological substrate of glucosyltransferase is omega-hydroxyceramide (C30) or non-omega-hydroxylated ceramides. Of those, only non-omega-hydroxylated ceramides proved to be good substrates for glucosyltransferase in vitro. Our parallel in vitro study also demonstrated that murine epidermis contains enzymatic activity by which omega-hydroxyglucosylceramide or omega-hydroxyceramide can be converted to acylglucosylceramide or acylceramide. Collectively, these findings indicate that the majority of acylceramides found in the stratum corneum may be synthesized through a distinct sequence of enzymatic reactions consisting of the glucosylation of ceramides by glucosyltransferase, omega-hydroxylation of glucosylceramide, the acylation of omega-hydroxyglucosylceramide (possibly by an omega-acyltransferase), and the deglucosylation of acylglucosylceramide by beta-glucocerebrosidase.
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Ceramidas/metabolismo , Epiderme/metabolismo , Glucosilceramidase/antagonistas & inibidores , Glucosiltransferases/antagonistas & inibidores , Acilação , Aciltransferases/fisiologia , Animais , Glucosilceramidas/metabolismo , Glicosilação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Especificidade por SubstratoRESUMO
The O-linked-N-acetylglucosamine (O-GlcNAc) modification of cytoplasmic and nuclear proteins regulates basic cellular functions and is involved in the aetiology of diabetes and neurodegeneration. This intracellular O-GlcNAcylation is catalyzed by a single O-GlcNAc transferase, OGT. Here we report a novel OGT, EOGT, responsible for extracellular O-GlcNAcylation. Although both OGT and EOGT are regulated by hexosamine flux, EOGT localizes to the lumen of the endoplasmic reticulum and transfers GlcNAc to epidermal growth factor-like domains in an OGT-independent manner. Loss of Eogt gives phenotypes similar to those caused by defects in the apical extracellular matrix. Dumpy (Dp), a membrane-anchored extracellular protein, is O-GlcNAcylated, and EOGT is required for Dp-dependent epithelial cell-matrix interactions. Thus, O-GlcNAcylation of secreted and membrane glycoproteins is a novel mediator of cell-cell or cell-matrix interactions at the cell surface.
Assuntos
Acetilglucosamina/metabolismo , Comunicação Celular/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Células Epiteliais/metabolismo , Proteínas da Matriz Extracelular/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Acilação , Sequência de Aminoácidos , Animais , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Drosophila melanogaster/enzimologia , Fator de Crescimento Epidérmico/química , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/metabolismo , Células Epiteliais/citologia , Proteínas da Matriz Extracelular/genética , Hexosaminas/metabolismo , Camundongos , Dados de Sequência Molecular , N-Acetilglucosaminiltransferases/química , N-Acetilglucosaminiltransferases/genética , Plasmídeos , Ligação Proteica , Processamento de Proteína Pós-Traducional/genética , Estrutura Terciária de Proteína , Interferência de RNA , Homologia de Sequência de Aminoácidos , Transdução de Sinais , TransfecçãoRESUMO
The effects of exposure to hyperbaric oxygen on the oxidative capacity of the skeletal muscles in mice at different ages were investigated. We exposed 5-, 34-, 55-, and 88-week-old mice to 36% oxygen at 950 mmHg for 6 hours per day for 2 weeks. The activities of succinate dehydrogenase (SDH), which is a mitochondrial marker enzyme, of the tibialis anterior muscle in hyperbaric mice were compared with those in age-matched mice under normobaric conditions (21% oxygen at 760 mmHg). Furthermore, the SDH activities of type IIA and type IIB fibers in the muscle were determined using quantitative histochemical analysis. The SDH activity of the muscle in normobaric mice decreased with age. Similar results were observed in both type IIA and type IIB fibers in the muscle. The decrease in the SDH activity of the muscle was reduced in hyperbaric mice at 57 and 90 weeks. The decreased SDH activities of type IIA and type IIB fibers were reduced in hyperbaric mice at 90 weeks and at 57 and 90 weeks, respectively. We conclude that exposure to hyperbaric oxygen used in this study reduces the age-related decrease in the oxidative capacity of skeletal muscles.
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PURPOSE: To determine the feasibility and efficacy of preoperative concurrent chemoradiation therapy (CCRT) with S-1, an oral fluoropyrimidine derivative, in patients with T4 oral squamous cell carcinoma (SCC). METHODS AND MATERIALS: Only patients with histologically proven T4 oral SCC were included. Radiotherapy (total dose, 30 Gy) was delivered in 2-Gy daily fractions over a period of 3 weeks. Concurrently, S-1 (80 mg/m(2)/day) was administered orally twice daily for 14 consecutive days. RESULTS: We enrolled 46 patients. All underwent radiotherapy as planned; however, oral S-1 was discontinued in 3 patients who manifested acute toxicity. Grade 3 toxicities were mucositis (20%), anorexia (9%), and neutropenia (4%). We encountered no Grade 4 adverse events or serious postoperative morbidity requiring surgical intervention. After CCRT, 32 of the 46 patients underwent radical resection; in 17 (53%) of the operated patients, the pathologic response was complete. During follow-up ranging from 7 to 58 months (median, 22 months), tumor control failed in 5 (16%) of the 32 operated patients; there were 3 local and 2 regional failures. Of the 14 non-operated patients, 8 (57%) manifested local (n = 7) or regional failure (n = 1). The 3-year overall survival rate for all 46 patients was 69%; it was significantly higher for operated than for non-operated patients (82% vs. 48%; p = 0.0288). CONCLUSION: Preoperative CCRT with S-1 is feasible and effective in patients with T4 oral SCC. Even in inoperable cases, CCRT with S-1 provides adequate tumor control.