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1.
Mol Cell ; 79(1): 43-53.e4, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32464093

RESUMO

The physiological role of immune cells in the regulation of postprandial glucose metabolism has not been fully elucidated. We have found that adipose tissue macrophages produce interleukin-10 (IL-10) upon feeding, which suppresses hepatic glucose production in cooperation with insulin. Both elevated insulin and gut-microbiome-derived lipopolysaccharide in response to feeding are required for IL-10 production via the Akt/mammalian target of rapamycin (mTOR) pathway. Indeed, myeloid-specific knockout of the insulin receptor or bone marrow transplantation of mutant TLR4 marrow cells results in increased expression of gluconeogenic genes and impaired glucose tolerance. Furthermore, myeloid-specific Akt1 and Akt2 knockout results in similar phenotypes that are rescued by additional knockout of TSC2, an inhibitor of mTOR. In obesity, IL-10 production is impaired due to insulin resistance in macrophages, whereas adenovirus-mediated expression of IL-10 ameliorates postprandial hyperglycemia. Thus, the orchestrated response of the endogenous hormone and gut environment to feeding is a key regulator of postprandial glycemia.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Hiperglicemia/patologia , Insulina/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Tecido Adiposo/metabolismo , Animais , Glicemia/análise , Gluconeogênese/genética , Hiperglicemia/etiologia , Hiperglicemia/metabolismo , Hipoglicemiantes/farmacologia , Resistência à Insulina , Interleucina-10/fisiologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Knockout , Período Pós-Prandial , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Proteína 2 do Complexo Esclerose Tuberosa/fisiologia
2.
Int J Med Sci ; 20(1): 136-141, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36619223

RESUMO

Objectives: There are currently no appropriate markers and target for prophylaxis against COVID-19-related thrombosis, especially in the not-severe cases. We tested the hypothesis that inflammation is a suitable marker and target for prophylaxis against COVID-19-related thrombosis. Methods: Data of all 32 COVID-19 patients admitted to Saitama Medical Center between January 1 and March 30, 2021, were analyzed. Patients were divided into severe (requiring oxygen, n=12) and non-severe (no requirement for oxygen, n=20), and also those with high C-reactive protein (CRP) level (cutoff value: 30 mg/L, n=21) and low-CRP (n=11). We also compared the clinical and laboratory data of a 46-year-old post-liver transplant male patient, who was treated with a combination of immunosuppressants (methylprednisolone, fludrocortisone, cyclosporine, and everolimus) with those of other COVID-19 patients, using the Smirnoff-Grubbs and Box plots tests. Results: The levels of CRP, ferritin, lactate dehydrogenase, aspartate aminotransferase, and thrombin-antithrombin complex (TAT) were significantly higher in the high-severity group than the low-severity group; while other coagulation parameters were comparable. The time between onset of illness and blood levels of lactate dehydrogenase, fibrinogen, D-dimer, TAT, and plasmin alpha2-plasmin inhibitor complex (PIC) were significantly higher whereas lymphocyte count was significantly lower in the high-CRP group. Extremely low levels of TAT, PIC, and plasminogen activator inhibitor-1 (PAI-1) were recorded in the liver transplant patient treated with immunosuppressants. The TAT, PIC, and PAI-1 levels were deemed outliers. Conclusions: Inflammation is a potentially suitable marker and target for prophylaxis against COVID-19-related thrombosis.


Assuntos
COVID-19 , Trombose , Humanos , Masculino , Pessoa de Meia-Idade , COVID-19/complicações , Inibidor 1 de Ativador de Plasminogênio , Inflamação/tratamento farmacológico , Trombose/tratamento farmacológico , Trombose/etiologia , Trombose/prevenção & controle , Oxigênio , Imunossupressores , Lactato Desidrogenases
3.
Biochem Biophys Res Commun ; 582: 35-42, 2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34688045

RESUMO

High protein diet (HPD) is an affordable and positive approach in prevention and treatment of many diseases. It is believed that transcriptional regulation is responsible for adaptation after HPD feeding and Kruppel-like factor 15 (KLF15), a zinc finger transcription factor that has been proved to perform transcriptional regulation over amino acid, lipid and glucose metabolism, is known to be involved at least in part in this HPD response. To gain more insight into molecular mechanisms by which HPD controls expressions of genes involved in amino acid metabolism in the liver, we performed RNA-seq analysis of mice fed HPD for a short period (3 days). Compared to a low protein diet, HPD feeding significantly increased hepatic expressions of enzymes involved in the breakdown of all the 20 amino acids. Moreover, using KLF15 knockout mice and in vivo Ad-luc analytical system, we were able to identify Cth (cystathionine gamma-lyase) as a new target gene of KLF15 transcription as well as Ast (aspartate aminotransferase) as an example of KLF15-independent gene despite its remarkable responsiveness to HPD. These findings provide us with a clue to elucidate the entire transcriptional regulatory mechanisms of amino acid metabolic pathways.


Assuntos
Aspartato Aminotransferases/genética , Cistationina gama-Liase/genética , Dieta Rica em Proteínas/métodos , Fatores de Transcrição Kruppel-Like/genética , Transcrição Gênica , Adaptação Fisiológica/genética , Aminoácidos/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Cistationina gama-Liase/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genes Reporter , Glucose/metabolismo , Fatores de Transcrição Kruppel-Like/deficiência , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Luciferases , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Análise de Sequência de RNA , Transdução de Sinais
4.
Biochem Biophys Res Commun ; 493(1): 40-45, 2017 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-28928093

RESUMO

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have both anti-diabetic and anti-obesity effects. However, the precise mechanism of the anti-obesity effect remains unclear. We previously demonstrated that the glycogen depletion signal triggers lipolysis in adipose tissue via liver-brain-adipose neurocircuitry. In this study, therefore, we investigated whether the anti-obesity mechanism of SGLT2 inhibitor is mediated by this mechanism. Diet-induced obese mice were subjected to hepatic vagotomy (HVx) or sham operation and loaded with high fat diet containing 0.015% tofogliflozin (TOFO), a highly selective SGLT2 inhibitor, for 3 weeks. TOFO-treated mice showed a decrease in fat mass and the effect of TOFO was attenuated in HVx group. Although both HVx and sham mice showed a similar level of reduction in hepatic glycogen by TOFO treatment, HVx mice exhibited an attenuated response in protein phosphorylation by protein kinase A (PKA) in white adipose tissue compared with the sham group. As PKA pathway is known to act as an effector of the liver-brain-adipose axis and activate triglyceride lipases in adipocytes, these results indicated that SGLT2 inhibition triggered glycogen depletion signal and actuated liver-brain-adipose axis, resulting in PKA activation in adipocytes. Taken together, it was concluded that the effect of SGLT2 inhibition on weight loss is in part mediated via the liver-brain-adipose neurocircuitry.


Assuntos
Tecido Adiposo/fisiologia , Compostos Benzidrílicos/administração & dosagem , Encéfalo/fisiologia , Glucosídeos/administração & dosagem , Fígado/fisiologia , Inibidores do Transportador 2 de Sódio-Glicose , Transportador 2 de Glucose-Sódio/metabolismo , Redução de Peso/fisiologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/inervação , Animais , Fármacos Antiobesidade/administração & dosagem , Encéfalo/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/inervação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Vagotomia , Nervo Vago/efeitos dos fármacos , Nervo Vago/fisiologia , Nervo Vago/cirurgia
5.
Biochem Biophys Res Commun ; 465(4): 857-63, 2015 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-26321664

RESUMO

Fatty acid elongase 5 (ELOVL5) is an enzyme involved in the synthesis of polyunsaturated fatty acids. Sterol Regulatory Element-binding Protein (SREBP)-1 activates ELOVL5 and increases polyunsaturated fatty acid synthesis, which in turn negatively affects SREBP-1 expression. Thus, ELOVL5 has been established as an SREBP-1 target gene and an important component of the negative feedback loop of de novo lipogenesis. However, the human ELOVL5 promoter/enhancer has not been fully analyzed and the location of SREBP biding sites around the ELOVL5 gene has yet to be defined. Here we performed a detailed promoter/enhancer analysis of human ELOVL5 gene, and identified two new SREBP binding sites, one in the 10 kb upstream region and one in the exon 1. These two SRE motifs are conserved among mammals and the mechanism found in the present study by which SREBP activates ELOVL5 is considered to be common in mammals. Through these findings, we clarified the molecular mechanism how SREBP activates ELOVL5, an important regulator of de novo lipogenesis.


Assuntos
Acetiltransferases/genética , Elementos Facilitadores Genéticos , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Animais , Sequência de Bases , Sítios de Ligação/genética , Éxons , Elongases de Ácidos Graxos , Ácidos Graxos Insaturados/metabolismo , Ácidos Graxos Insaturados/farmacologia , Células HEK293 , Humanos , Lipogênese/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Regulação para Cima
6.
FEBS J ; 291(2): 259-271, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37702262

RESUMO

During periods of fasting, the body undergoes a metabolic shift from carbohydrate utilization to the use of fats and ketones as an energy source, as well as the inhibition of de novo lipogenesis and the initiation of gluconeogenesis in the liver. The transcription factor sterol regulatory element-binding protein-1 (SREBP-1), which plays a critical role in the regulation of lipogenesis, is suppressed during fasting, resulting in the suppression of hepatic lipogenesis. We previously demonstrated that the interaction of fasting-induced Kruppel-like factor 15 (KLF15) with liver X receptor serves as the essential mechanism for the nutritional regulation of SREBP-1 expression. However, the underlying mechanisms of KLF15 induction during fasting remain unclear. In this study, we show that the glucocorticoid receptor (GR) regulates the hepatic expression of KLF15 and, subsequently, lipogenesis through the KLF15-SREBP-1 pathway during fasting. KLF15 is necessary for the suppression of SREBP-1 by GR, as demonstrated through experiments using KLF15 knockout mice. Additionally, we show that GR is involved in the fasting response, with heightened binding to the KLF15 enhancer. It has been widely known that the hypothalamic-pituitary-adrenal (HPA) axis regulates the secretion of glucocorticoids and plays a significant role in the metabolic response to undernutrition. These findings demonstrate the importance of the HPA-axis-regulated GR-KLF15 pathway in the regulation of lipid metabolism in the liver during fasting.


Assuntos
Lipogênese , Receptores de Glucocorticoides , Camundongos , Animais , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Lipogênese/genética , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Regiões Promotoras Genéticas , Fígado/metabolismo , Jejum
7.
JCI Insight ; 8(17)2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37681411

RESUMO

Nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes are interacting comorbidities of obesity, and increased hepatic de novo lipogenesis (DNL), driven by hyperinsulinemia and carbohydrate overload, contributes to their pathogenesis. Fatty acid synthase (FASN), a key enzyme of hepatic DNL, is upregulated in association with insulin resistance. However, the therapeutic potential of targeting FASN in hepatocytes for obesity-associated metabolic diseases is unknown. Here, we show that hepatic FASN deficiency differentially affects NAFLD and diabetes depending on the etiology of obesity. Hepatocyte-specific ablation of FASN ameliorated NAFLD and diabetes in melanocortin 4 receptor-deficient mice but not in mice with diet-induced obesity. In leptin-deficient mice, FASN ablation alleviated hepatic steatosis and improved glucose tolerance but exacerbated fed hyperglycemia and liver dysfunction. The beneficial effects of hepatic FASN deficiency on NAFLD and glucose metabolism were associated with suppression of DNL and attenuation of gluconeogenesis and fatty acid oxidation, respectively. The exacerbation of fed hyperglycemia by FASN ablation in leptin-deficient mice appeared attributable to impairment of hepatic glucose uptake triggered by glycogen accumulation and citrate-mediated inhibition of glycolysis. Further investigation of the therapeutic potential of hepatic FASN inhibition for NAFLD and diabetes in humans should thus consider the etiology of obesity.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperglicemia , Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Camundongos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintases , Hiperglicemia/complicações , Leptina , Óxido Nítrico Sintase , Obesidade/complicações , Obesidade/genética
8.
J Biol Chem ; 285(15): 11681-91, 2010 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-20145241

RESUMO

Sterol regulatory element-binding protein (SREBP)-1 is a key transcription factor for the regulation of lipogenic enzyme genes in the liver. Polyunsaturated fatty acids (PUFA) selectively suppress hepatic SREBP-1, but molecular mechanisms remain largely unknown. To gain insight into this regulation, we established in vivo reporter assays to assess the activities of Srebf1c transcription and proteolytic processing. Using these in vivo reporter assays, we showed that the primary mechanism for PUFA suppression of SREBP-1 is at the proteolytic processing level and that this suppression in turn decreases the mRNA transcription through lowering SREBP-1 binding to the SREBP-binding element on the promoter ("autoloop regulatory circuit"), although liver X receptor, an activator for Srebf1c transcription, is not involved in this regulation by PUFA. The mechanisms for PUFA suppression of SREBP-1 confirm that the autoloop regulation for transcription is crucial for the nutritional regulation of triglyceride synthesis.


Assuntos
Ácidos Graxos Insaturados/metabolismo , Regulação da Expressão Gênica , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , Linhagem Celular , Núcleo Celular/metabolismo , Humanos , Fígado/metabolismo , Receptores X do Fígado , Masculino , Camundongos , Camundongos Endogâmicos ICR , Receptores Nucleares Órfãos/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Triglicerídeos/metabolismo
9.
Biochem Biophys Res Commun ; 404(1): 254-60, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21111707

RESUMO

We have previously demonstrated that neutral cholesterol ester hydrolase 1 (Nceh1) regulates foam cell formation and atherogenesis through the catalytic activity of cholesterol ester hydrolysis, and that Nceh1 and hormone-sensitive lipase (Lipe) are responsible for the majority of neutral cholesterol ester hydrolase activity in macrophages. There are several cholesterol ester-metabolizing tissues and cells other than macrophages, among which adrenocortical cells are also known to utilize the intracellular cholesterol for steroidogenesis. It has been believed that the mobilization of intracellular cholesterol ester in adrenal glands was facilitated solely by Lipe. We herein demonstrate that Nceh1 is also involved in cholesterol ester hydrolysis in adrenal glands. While Lipe deficiency remarkably reduced the neutral cholesterol ester hydrolase activity in adrenal glands as previously reported, additional inactivation of Nceh1 gene completely abrogated the activity. Adrenal glands were enlarged in proportion to the degree of reduced neutral cholesterol ester hydrolase activity, and the enlargement of adrenal glands and the accumulation of cholesterol esters were most pronounced in the Nceh1/Lipe double-deficient mice. Thus Nceh1 is involved in the adrenal cholesterol metabolism, and the cholesterol ester hydrolytic activity in adrenal glands is associated with the organ enlargement.


Assuntos
Glândulas Suprarrenais/anatomia & histologia , Colesterol/deficiência , Serina Proteases/genética , Esterol Esterase/genética , Glândulas Suprarrenais/citologia , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/enzimologia , Hormônio Adrenocorticotrópico/farmacologia , Animais , Expressão Gênica , Hidrólise , Masculino , Camundongos , Camundongos Mutantes , Tamanho do Órgão/efeitos dos fármacos
10.
iScience ; 24(12): 103446, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34988390

RESUMO

KLF15 is a transcription factor that plays an important role in the activation of gluconeogenesis from amino acids as well as the suppression of lipogenesis from glucose. Here we identified the transcription start site of liver-specific KLF15 transcript and showed that FoxO1/3 transcriptionally regulates Klf15 gene expression by directly binding to the liver-specific Klf15 promoter. To achieve this, we performed a precise in vivo promoter analysis combined with the genome-wide transcription-factor-screening method "TFEL scan", using our original Transcription Factor Expression Library (TFEL), which covers nearly all the transcription factors in the mouse genome. Hepatic Klf15 expression is significantly increased via FoxOs by attenuating insulin signaling. Furthermore, FoxOs elevate the expression levels of amino acid catabolic enzymes and suppress SREBP-1c via KLF15, resulting in accelerated amino acid breakdown and suppressed lipogenesis during fasting. Thus, the FoxO-KLF15 pathway contributes to switching the macronutrient flow in the liver under the control of insulin.

11.
BMJ Open ; 10(8): e034758, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32759240

RESUMO

OBJECTIVE: Persons with type 2 diabetes are often stigmatised for having what is considered a lifestyle-related disease. Accordingly, some blame themselves for their condition, resulting in feelings of low self-worth that ultimately impact their self-management behaviours. However, there are no studies examining why some do not blame themselves for their condition and manage to maintain their self-worth in relation to their illness. This study aimed to explore an understanding of how such persons experience the maintenance of self-worth in relation to their illness over the lifelong course of treatment. DESIGN: A cross-sectional qualitative study. Face-to-face semistructured interviews were conducted with a purposive sampling strategy. The data was analysed using a qualitative descriptive method that involved concurrent data collection and constant comparative analysis. SETTING: Two tertiary-level hospitals in Japan. PARTICIPANTS: Thirty-three outpatients with type 2 diabetes who currently had good glycaemic control but had previously had poor glycaemic control. RESULTS: Three themes explaining the maintenance of self-worth were identified: (1) Participants gained 'control' over their illness by living a 'normal life.' They found a way to eat preferred foods, dine out with family and friends, travel and work as usual; (2) Participants discovered the positive aspects of type 2 diabetes, as they felt 'healthier' from the treatment and felt a sense of security and gratitude for the care they received from healthcare professionals; (3) Participants discovered a new sense of self-worth by moving towards goals for type 2 diabetes treatment and experienced inner growth through positive lifestyle choices. CONCLUSIONS: The process of restoring and maintaining self-worth should be brought to the attention of healthcare professionals in diabetes care. These professionals could help patients discover positive self-representations through diabetes treatment (eg, a realisation that one does not lack self-control) and could aid in increasing patient engagement in diabetes self-management.


Assuntos
Diabetes Mellitus Tipo 2 , Autogestão , Estudos Transversais , Diabetes Mellitus Tipo 2/terapia , Humanos , Japão , Pesquisa Qualitativa
12.
Biochem Biophys Res Commun ; 387(3): 511-5, 2009 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-19619509

RESUMO

It has long been a matter of debate whether the hormone-sensitive lipase (HSL)-mediated lipolysis in pancreatic beta-cells can affect insulin secretion through the alteration of lipotoxicity. We generated mice lacking both leptin and HSL Lep(ob/ob)/HSL(-/-) and explored the role of HSL in pancreatic beta-cells in the setting of obesity. Lep(ob/ob)/HSL(-/-) developed elevated blood glucose levels and reduced plasma insulin levels compared with Lep(ob/ob)/HSL(+/+) in a fed state, while the deficiency of HSL did not affect glucose homeostasis in Lep(+/+) background. The deficiency of HSL exacerbated the accumulation of triglycerides in Lep(ob/ob) islets, leading to reduced glucose-stimulated insulin secretion. The deficiency of HSL also diminished the islet mass in Lep(ob/ob) mice due to decreased cell proliferation. In conclusion, HSL affects insulin secretary capacity especially in the setting of obesity.


Assuntos
Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Obesidade/enzimologia , Esterol Esterase/deficiência , Animais , Glicemia/metabolismo , Proliferação de Células , Insulina/sangue , Secreção de Insulina , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/enzimologia , Camundongos , Camundongos Knockout , Esterol Esterase/genética , Triglicerídeos/metabolismo
13.
SAGE Open Med ; 7: 2050312119865647, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31384463

RESUMO

OBJECTIVES: The aim of this study is to empirically examine a full pathway model of health literacy, and health and well-being outcomes among patients with type 2 diabetes. METHODS: A three-wave longitudinal survey was administered to 148 patients with diabetes. Covariance structure analysis was conducted to create a path diagram, with health literacy and burden of medical expenses included as independent variables and with psychosocial factors, behaviors, and health and well-being outcomes included as dependent variables. RESULTS: The model fit indices showed a comparative fit index of 0.985 at baseline, 0.959 after 3 months, and 0.948 after 6 months, with a root mean square error of approximation of 0.040 at baseline, 0.079 after 3 months, and 0.085 after 6 months. There were 14 significant paths across the three time points between health literacy and understanding of diabetes care, self-efficacy, communication with doctors, and medication adherence. CONCLUSION: The model fitness index showed an adequate result. Health literacy was significantly positively associated with understanding of diabetes care, self-efficacy, communication with doctors, and medication adherence. Health literacy had a direct positive influence on medication adherence and possibly an indirect positive influence on exercise/diet via self-efficacy. The results were generally consistent across the three time points, suggesting good reliability of the models. Improving health literacy may lead to better self-management of diabetes and favorable health outcomes.

14.
FEBS Lett ; 593(4): 423-432, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30659595

RESUMO

Glucocorticoids have various medical uses but are accompanied by side effects. The glucocorticoid receptor (GR) has been reported to regulate the clock genes, but the underlying mechanisms are incompletely understood. In this study, we focused on the suppressive effect of the GR on the expression of Rev-erbα (Nr1d1), an important component of the clock regulatory circuits. Here we show that the GR suppresses Rev-erbα expression via the formation of a complex with CLOCK and BMAL1, which binds to the E-boxes in the Nr1d1 promoter. In this GR-CLOCK-BMAL1 complex, the GR does not directly bind to DNA, which is referred to as tethering. These findings provide new insights into the role of the GR in the control of circadian rhythm.


Assuntos
Fatores de Transcrição ARNTL/metabolismo , Proteínas CLOCK/metabolismo , Dexametasona/administração & dosagem , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética , Receptores de Glucocorticoides/metabolismo , Animais , Ritmo Circadiano/efeitos dos fármacos , Dexametasona/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Células Hep G2 , Humanos , Masculino , Camundongos , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/química , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Regiões Promotoras Genéticas , Receptores de Glucocorticoides/agonistas
15.
Hepatol Res ; 38(6): 593-600, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18070054

RESUMO

AIM: Hepatocyte transplantation is a potential alternative to whole organ liver transplantation. To realize this procedure, a hepatocyte bank system capable of supplying large numbers of hepatocytes must be established. We previously reported an easy method for cryopreserving hepatocytes using a microencapsulation technique. Here, we investigated how cryoinjury to microencapsulated hepatocytes could be avoided during cryopreservation. METHODS: Hepatocytes from Sprague-Dawley rats were harvested in situ using a two-step ethylenediaminetetraacetic acid (EDTA)/collagenase digestion protocol. The cells were microencapsulated using alginate-poly L-lysine. The microencapsulated hepatocytes were put into vials and immediately immersed in liquid nitrogen. The growth of ice crystals in the vials containing the microencapsulated hepatocytes was observed using cryomicroscopy. The microencapsulated hepatocytes were sectioned for ultrastructural examination to investigate their intracellular conditions. Finally, total RNA was isolated from the cryopreserved microencapsulated hepatocytes and analyzed for hepatocyte nuclear factor (HNF) using reverse transcriptase polymerase chain reaction (RT-PCR) analysis. RESULTS: Cryomicroscopy showed that the alginate microencapsulation technique protected the hepatocytes from physical damage caused by the growth of extracellular ice crystals. Ultrastructural examination revealed that the intracellular environment of the microencapsulated hepatocytes was maintained. The RT-PCR analysis additionally suggested that the alginate gel also maintained the HNF level. CONCLUSION: Our microencapsulation technique protects hepatocytes from cryoinjury. This novel technique could be utilized by hepatocyte banks.

16.
Orphanet J Rare Dis ; 13(1): 208, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30458817

RESUMO

BACKGROUND: There is now an international partnership to establish global programs for patients with rare and undiagnosed diseases, involving interdisciplinary expert panels and phenotype-driven genetic analyses utilizing next-generation sequencing and analytics. Whereas it is crucial to have data such as the actual number of undiagnosed patients, to help inform the implementation plan with such programs, there have been no systematic studies to quantitate the numbers of patients principally because of the inherent difficulty in most health systems to identify patients whose condition has not yet been diagnosed and coded. Our national experience with a rare disease program, Nan-Byo which was established in 1972, and the more recently expanded Initiative on Rare and Undiagnosed Diseases (IRUD), provided a unique opportunity to design a cross-sectional study to ascertain the undiagnosed patients in Japan based on the IRUD referral criteria. RESULTS: Two rounds of online surveys were performed: one survey targeting physicians affiliated with general hospitals (GH) and family clinics (FC) (the response rate: 30.6% (242/792)) and one nationwide survey targeting university hospitals (UH) in Japan (47.1% (839/1781)). A high percentage of doctors needing IRUD was seen in pediatrics at GH, FC, while there was a clear demand for IRUD in most departments at UH. We calculated the number of undiagnosed patients in Japan, as the "percentage of doctors needing IRUD" × "number of patients who would be referred to IRUD per doctor needing IRUD (cases/person)" × "total number of doctors in the relevant facilities in Japan (persons)", resulting in 3681 cases in pediatrics/pediatric surgery and 33,703 cases in other departments, for a total of 37,384 cases. CONCLUSIONS: Our study revealed the extant demand for IRUD in most departments and 37,000+ potential patients with undiagnosed diseases in the Japanese health system. These data inform the establishment of an equitable, sustainable, efficient and effective outpatient-based IRUD. These findings would serve as a valuable reference for undiagnosed diseases programs in different international jurisdictions and for countries and regions who also share vision(s) for societal implementation that help to advance international efforts to support patients with rare diseases who are direly waiting for diagnosis, subsequent treatment and care.


Assuntos
Doenças Raras/epidemiologia , Adulto , Estudos Transversais , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Doenças Raras/genética , Inquéritos e Questionários , Adulto Jovem
17.
FEBS Lett ; 592(3): 422-433, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29331016

RESUMO

The SNP rs7903146 at the transcription factor 7-like 2 (TCF7L2) locus is established as the strongest known genetic marker for type 2 diabetes via genome-wide association studies. However, the functional SNPs regulating TCF7L2 expression remain unclear. Here, we show that the SNP rs7074440 is a candidate functional SNP highly linked with rs7903146. A reporter plasmid with rs7074440 normal allele sequence exhibited 15-fold higher luciferase activity compared with risk allele sequence in hepatocytes, demonstrating a strong enhancer activity at rs7074440. Additionally, we identified C-FOS as an activator binding to the rs7074440 enhancer using a TFEL genome-wide screen method. Consistently, knockdown of C-FOS significantly reduced TCF7L2 expression in hepatocytes. Collectively, a novel enhancer regulating TCF7L2 expression was revealed through searching for functional SNPs.


Assuntos
Diabetes Mellitus Tipo 2/genética , Hepatócitos/metabolismo , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Animais , Linhagem Celular , Feminino , Expressão Gênica , Células HEK293 , Células Hep G2 , Hepatócitos/citologia , Humanos , Masculino , Camundongos
18.
Cell Transplant ; 16(1): 67-73, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17436856

RESUMO

Transplantation of isolated hepatocytes has been proposed to compensate for essential functions lacking in liver failure or for genetic defects that alter a specific liver metabolic pathway. Hepatocyte utilization for these purposes would be facilitated with a reliable, reproducible, and effective method of long-term hepatocyte storage. We have recently developed a simple new system for cryopreservation of hepatocytes that encapsulates alginate microspheres and maintains liver-specific function. The aim of this study was to elucidate the transport and drug-metabolizing enzyme activities of cryopreserved microencapsulated hepatocytes stored for a long time. Morphological examinations showed there is no apparent injury of the hepatocytes during cryopreservation processes. A drug-metabolizing enzyme (testosterone 6beta-hydroxylase, a specific probe for CYP3A2) and drug transport activities [salicylate, allopurinol, and prostaglandin E2 (PGE2), typical substrates of rOat2] in cryopreserved microencapsulated hepatocytes were maintained up to 120 days. Our results thus demonstrate for the first time that cryopreservation of primary rat hepatocytes by the encapsulation technique allows long-term retention of drug metabolism and drug transport activities.


Assuntos
Criopreservação/métodos , Sistema Enzimático do Citocromo P-450/metabolismo , Hepatócitos , Microssomos/metabolismo , Esteroide Hidroxilases/metabolismo , Alopurinol/metabolismo , Animais , Transporte Biológico , Transplante de Células , Dinoprostona/metabolismo , Hepatócitos/citologia , Hepatócitos/enzimologia , Hepatócitos/transplante , Masculino , Ratos , Ratos Sprague-Dawley , Salicilatos/metabolismo , Fatores de Tempo
19.
BMJ Open Diabetes Res Care ; 5(1): e000322, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28243450

RESUMO

OBJECTIVES: To examine the prevalence of the willingness of patients with diabetes to use a self-management tool based on information and communication technology (ICT) such as personal computers, smartphones, and mobile phones; and to examine the patient characteristics associated with that willingness. RESEARCH DESIGN AND METHODS: We conducted a cross-sectional interview survey of 312 adults with diabetes at a university hospital in an urban area in Japan. Participants were classified into 2 groups: those who were willing to use an ICT-based self-management tool and those who were unwilling. Multiple logistic regression analysis was used to identify factors associated with the willingness, including clinical and social factors, current use of ICT, self-management practices, self-efficacy, and diabetes-related emotional distress. RESULTS: The mean age of the 312 participants was 66.3 years (SD=11.5) and 198 (63%) were male. Most of the participants (93%) had type 2 diabetes. Although only 51 (16%) currently used ICT-based self-management tools, a total of 157 (50%) expressed the willingness to use such a tool. Factors associated with the willingness included: not having nephropathy (OR=2.02, 95% CI 1.14 to 3.58); outpatient visits once a month or more (vs less than once a month, OR=2.13, 95% CI 1.13 to 3.99); current use of personal computers and/or smartphones (OR=4.91, 95% CI 2.69 to 8.98); and having greater diabetes-related emotional distress (OR=1.10, 95% CI 1.01 to 1.20). CONCLUSIONS: Approximately half of the patients showed interest in using an ICT-based self-management tool. Willing patients may expect ICT-based self-management tools to complement outpatient visits and to make self-management easier. Starting with patients who display the willingness factors might optimize programs based on such tools.

20.
FEBS Lett ; 591(7): 965-978, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28281280

RESUMO

Fatty acid synthase (Fasn) is a key component of energy metabolism that is dynamically induced by food intake. Although extensive studies have revealed a number of transcription factors involved in the fasting/refeeding transition of Fasn expression in hepatocytes, much less evidence is available for adipocytes. Using the in vivo Ad-luc analytical system, we identified the inverted CCAAT element (ICE) around -100 nucleotides in the Fasn promoter as a critical cis-element for the refeeding response in adipocytes. Electrophoretic mobility shift assays and chromatin immunoprecipitation show that nuclear factor Y (NF-Y) binds to ICE specifically in refeeding states. Notably, the NF-Y binding to ICE is differently regulated between adipocytes and hepatocytes. These findings provide insights into the specific mechanisms controlling energy metabolism in adipocytes.


Assuntos
Adipócitos/metabolismo , Fator de Ligação a CCAAT/metabolismo , Ácido Graxo Sintases/metabolismo , Comportamento Alimentar , Células 3T3-L1 , Adenoviridae/genética , Adipócitos/citologia , Tecido Adiposo Branco/metabolismo , Animais , Sequência de Bases , Fator de Ligação a CCAAT/genética , Imunoprecipitação da Cromatina , Ensaio de Desvio de Mobilidade Eletroforética , Ácido Graxo Sintases/genética , Regulação da Expressão Gênica , Immunoblotting , Fígado/metabolismo , Luciferases/genética , Luciferases/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Mutação , Regiões Promotoras Genéticas/genética , Ligação Proteica , Elementos de Resposta/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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